Physical Sciences and Mathematics Commons^™

Antimicrobial And Cytotoxic Properties Of Extracts From Over-Seasoned Worm-Casts Of The Earthworm Hyperiodrilus Africanus Beddard, 1891, Stephen Olugbemiga Owa, David Adeiza Otohinoyi, Theresa Ibibia Edewor-Ikupoyi, Adeolu Adeola Taiwo, Jenifer Akhere Okosun, Yvonne Oluchi Akujobi, Damilola Grace Oyewale, Tomilola Debby Olaolu, Damilare Emmanuel Rotimi, Osarenkhoe Omorefosa Osemwegie, Oluyomi Stephen Adeyemi

Karbala International Journal of Modern Science

⦁ Background: Despite the continuous interest in the search for therapeutic agents, little attention has been given to the medicinal relevance of earthworm casts, with even less interest in over-seasoned worm-casts. Therefore, this study determined the phytochemical, antimicrobial, and cytotoxic properties of over-seasoned worm-casts of the earthworm Hyperiodrilus africanus (Eudrilidae). Methods: The earthworm casts were extracted with n-hexane, ethanol, and water and the crude extracts were evaluated for the presence of chemical constituents and antimicrobial properties. Cytotoxicity was inferred from the antimitotic effects of the extracts on the radicles of germinating seeds of Sorghum bicolor. Results: The chemical constituent determinations …

A Review On The Ethnobotanical, Phytochemistry, And Pharmacological Activities Of Aristolochia Longa L., Oluwafemi Adeleke Ojo, Matthew Iyobhebhe, Bukola Atunwa, Adebola Busola Ojo

Karbala International Journal of Modern Science

Aristolochia longa L. is a plant native to Algeria and Morocco that has been used by the locals to combat different arrays of infections and diseases found among them. This particular plant is well-known for its therapeutic qualities that could be traced back to the presence of many effective phytochemicals that have been extrapolated from the different parts of the plant, like the leaves and roots: flavonoids, saponins, tannins, 4-hydroxybenzoic acid, β-carotenes, limonenes, and palmitic acids. This plant has been identified in different research articles to be able to manage diseases effectively because it possesses some pharmacological attributes such as; …

Applicability Limits Of The End Face Fiber-Optic Gas Concentration Sensor, Based On Fabry-Perot Interferometer, S.M.R.H. Hussein, A.Zh. Sakhabutdinov, O.G. Morozov, V.I. Anfinogentov, J.A. Tunakova, A.R. Shagidullin, A.A. Kuznetsov, K.A. Lipatnikov, A.R. Nasybullin

Karbala International Journal of Modern Science

The mathematical model of the fiber-optic sensor for gas concentration analysis is under study. The sensor is imple-mented as Fabry-Perot interferometer at the end face of the optical fiber by applying a thin polymer film, which permit-tivity depends on the tested gas concentration. It is shown, that a change in the properties of the optical fiber or the at-mosphere permittivity leads mainly to the spectrum contrast changing and does not change the period and the wave-length shift of its comb. The influence of the polymer film thickness, the environment temperature and humidity on the Fabry-Perot spectrum is analyzed. The necessity …

Molecular Docking Reveals Phytoconstituents Of The Methanol Extract From Muntingia Calabura As Promising Α-Glucosidase Inhibitors, Nurlena Andalia, Muhammad N. Salim, Nurdin Saidi, Muhammad Ridhwan, Muhammad Iqhrammullah, Ummu Balqis

Karbala International Journal of Modern Science

Inhibition of α-glucosidase has been used as a management of type 2 diabetes mellitus, where studies are focused on finding more efficacious and safe drugs. Herein, the research aimed to unveil the potential of phytoconstituents contained in methanol extract of Muntingia calabura leaves in inhibiting α-glucosidase through molecular docking simulation. From a systematic search (Scopus), we found 5 eligible articles and identified 28 phytocompounds. Fisetin, pinostrobin, and rhamnetin identified in M. calabura extract were predicted to have good bioavailability. Finally, fisetin was revealed as the most potential α-glucosidase inhibitor candidate with a binding affinity of -7.5 kcal/mol.

Functional Bottlebrush Polymer Additives For Thin Films And Coatings, Travis S. Laws

Doctoral Dissertations

Bottlebrush polymers are a class of highly branched polymers consisting of polymeric side chains that are densely grafted to a linear backbone. Their highly branched architecture results in surface enrichment across a broad range of materials. The goal of my research has been centered around the design of functional bottlebrush polymers and their use as surface active additives in blend films and coatings.

In the first chapter, we examine the segregation behavior of polystyrene bottlebrushes that are blended with linear polystyrene. We systematically vary the lengths of the bottlebrush backbone (Nb), side-chain (Nsc), and the linear matrix (Nm) in order …

How Dynamic Bond Results In The Unique Viscoelastic Behavior Of The Associating Polymers, Sirui Ge

Doctoral Dissertations

Associating polymer is a special kind of polymer possessing transient reversible bonds in addition to the conventional covalent bonds. The reversible bonds provide unique dynamics and fascinating viscoelastic properties, resulting in attractive applications for these polymers, such as self-healing and shape memory materials. Despite many years of studies, the understanding of dynamics of polymers with reversible bonds, especially on molecular level, is still in the rudimentary stage, preventing the rational design of the potential novel functional materials based on associating polymers. In this dissertation, we provide a detailed and quantitative understanding of the dynamics and viscoelastic properties of associating polymers. …

Elucidating Molecular Structure And Interactions Of Disease-Related Noncovalent Assemblies Through Ion Mobility Spectrometry - Mass Spectrometry, Amber Leann Hope Gray

Doctoral Dissertations

Ion mobility spectrometry – mass spectrometry (IMS-MS) is a powerful gas-phase technique that is routinely employed in the investigations of amyloid oligomers and conformational studies due to its ability to separate isobaric and isomeric species with the same mass-to-charge ratio (m/z). The goal of this dissertation is to use IMS-MS as a primary platform to probe the conformational landscape of a macrocyclic protein, Cyclosporin A (CycA), and to characterize interactions of amyloidogenic assemblies. Through five independent studies presented within document, the limits of IMS-MS are pushed by employing conditions which mimic biological environments.

Chapter 2 focused on how …

College Of Natural Sciences Newsletter, July & August 2022, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 3, Issue 5

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Resources for Student Success
Page 4 Welcome to New Faculty & Staff
Page 5 Summer Activities in CNS
Page 9 Celebrating the lives of those who touched the College
Page 10 Media Coverage of CNS
Page 12 Open PRAIRIE Data
Page 13 Snaps from he start of the semester
Page 14 Science as Art Competition

A Natural Deep Eutectic Solvent - Protonated L-Proline-Xylitol - Based Stationary Phase For Gas Chromatography, Malwina Momotko, Justyna Łuczak, Andrzej Przyjazny, Grzegorz Boczkaj

Natural Sciences Publications

The paper presents a new kind of stationary phase for gas chromatography based on deep eutectic solvents (DES) in the form of a mixture of L-proline (protonated with hydrochloric acid) as a hydrogen bond acceptor (HBA) and xylitol as a hydrogen bond donor (HBD) in a molar ratio of HBA:HBD 5:1. DES immobilized on a silanized chromatographic support was tested by gas chromatography (GC) in order to determine its resolving power for volatile organic compounds. Studies have demonstrated the suitability of this type of DES as a stationary phase for GC. The Rohrschneider-McReynolds constants were determined for the synthesized DES, …

Synthesis, Characterization, And Reactivity Studies Of Highly Reduced Early-Metal Complexes Supported By Imidazolin-2-Iminato Ligands, Maria Alejandra Gomez Torres

Open Access Theses & Dissertations

Our group has shown that reduction of titanium complexes supported by the sterically encumbering N-donor ligands 1,3â??bis(Dipp)imidazolinâ??2â??iminato (ImDippNâ??) and ketimine guanidinate (ketGuan = [(tBuC=N)C(NDipp)2]-) gives access to electron rich platforms featuring a metal coordinated, reduced, dearomatized arene substituent, which act as an electronic reservoir capable of facilitating multi-electron transfer chemistry driven by the rearomatization driving force. For instance, the arene-masked Ti(II) synthon (DippketGuan)(η6-ImDippN)Ti (Dipp = 2,6-iPr2C6H3) (TiDipp) is a versatile and potent one- and two-electron reductant capable of distinctive late-metal type reactivity such as transfer hydrogenation and catalytic olefin hydrogenation. Interestingly, TiDipp can mediate the reversible cleavage of thiophene and, …

Variations In Copper Form Exposure Differentially Modulate Zea Mays (Corn) Physiological Responses, Carolina Valdes Bracamontes

Open Access Theses & Dissertations

In the present study, Zea mays seedlings grown under nano Cu(OH)2 (nCu), bulk Cu(OH)2 (bCu), and ionic CuSO4 (iCu) compound exposure were harvested after six days. The nutritional profile was determined to be significantly disrupted in the roots by 1000 ppm bCu treatment, resulting in a 58.7% reduction in potassium compared to the control. In the shoots, a significant decrease of manganese was observed for 10 and 1000 ppm iCu treatments with 55.7% and 64.2% reductions, respectively. The overall protein content and catalase (CAT) enzymatic activity, however, remained unaffected in either roots or shoots, while an absence of polyphenol oxidase …

Biological Interaction Of Mn-Based Nanomaterials With Capsicum Annuum L. Under Salinity Stress, Yuqing Ye

Open Access Theses & Dissertations

The foliar application of nanomaterials as a method to overcome abiotic stress is relatively new compared to their use as fertilizers or pesticides in agricultural practice. It is also vital to understand the interface between leaf and nanomaterials, as nanomaterials might translocate into crop edible tissues, thus, causing potential toxicity in living beings during food consumption. In this dissertation, salt-stressed Capsicum annuum L was exposed to manganese (Mn) -based nanomaterials (Mn2O3 nanoparticles (MnNPs) and graphene quantum dots doped with Mn (GQD-Mn)) at different stages (seed germination and full life cycle). The dissertation focuses on investigating the mechanism of how Mn-based …

Competition Between Halogen And Chalcogen Bonding And Their Role In Probing Organic Transformations, Andrew Peloquin

All Dissertations

Halogen bonding, the attractive interaction of an electrophilic region on a halogen atom with a nucleophilic region on another atom or molecule, provides a highly directional tool in forming solid-state motifs. This interaction, along with the related chalcogen bonding interactions, forms powerful synthons, which, when combined with other typical intermolecular attractions such as hydrogen bonding, allow for the design of supramolecular structures and inputs to crystal engineering. This dissertation research serves two primary purposes: (1) to catalog halogen and chalcogen bonding interactions with various donor molecules and (2) to utilize these interactions to probe interesting organic transformations.

In order to …

Isolation And Characterization Of Extracellular Vesicles From Various Biological Matrices Using Capillary-Channeled Polymer (C-Cp) Fiber Solid-Phase Extraction Spin-Down Tips, Kaylan Jackson

All Dissertations

A number of recent works have emphasized the need to isolate nanometer-scale analytes, like extracellular vesicles (EVs), from various biologically-relevant fluids. Exosomes are a subset of small EVs that range from 30-200 nm in diameter that serve as biomolecular snapshots of their cell of origin containing mother cell-specific DNA, miRNA, mRNA, and proteins. As critical components of intercellular communication, exosomes and other EVs play significant roles in many physiological and pathological processes. Diverse populations of these vesicles can be collected from biofluids, including blood, saliva, and urine, from cell culture conditioned media and primary cells, and even from plant …

Radioluminescence Based Biochemical Sensing And Imaging Strategies To Measure Local Drug Release And Ph, Gretchen B. Schober

All Dissertations

In this dissertation we describe methods for measuring infection relevant biochemical analytes using radioluminescent and ultrasound luminescent materials. Films and nanoparticles fabricated with europium doped gadolinium oxysulfide (Gd₂O₂S:Eu³⁺) are used to quantitatively measure radiolabeled pharmaceutical concentration, specifically tritium labeled vancomycin (³H-vancomycin). Europium and dysprosium doped strontium aluminate is used to fabricate an ultrasound modulated, pH sensing film. These methods are indicated for theranostic evaluation of implant associated infection. Bacterial biofilms are inherently resistant to traditional antibiotic treatment and can coat biomedical implants. These biofilm related infections are difficult or impossible to eradicate …

Understanding Dynamics Of Polymers Under Confinement: A Molecular Dynamics And Neutron Scattering Study, Supun Samindra Kamkanam Mohottalalage

All Dissertations

The current study probes the structure, dynamics, and rheological behavior of associating polymers including ionomers in melts and solutions as well as conjugated polymers confined into nanoparticles, using molecular dynamics (MD) simulations and neutron scattering techniques. The study focuses on two families of associative polymers, ion containing macromolecules and conjugated polymers.

Polymers that consist of ionizable groups along their backbone found uses in a broad range of applications. Examples include light weight energy storage and generation systems, and biomedical applications, where the polymers act as ion exchange membranes, and actuators. The ionic groups tend to form clusters that are in …

Dissolution And Electrochemical Recovery Of Uo2, Uo3, And U3o8 In Ionic Liquids, Katherine Iolani Thornock Luebke

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explores a novel method of increasing the solubility of uranium oxides and other actinide oxides in room temperature ionic liquids (IL) using direct dissolution. The goal is to further expand our knowledge of actinide dissolution and possible nuclear fuel cycle material applications using ionic liquids. The novelty of the methods is focused on the use of oxidizing gas generated using air passed through an ozone generator. While examples of dissolution exist in IL using acidic functionalized ionic liquids, the solubility of all possible oxide species was not demonstrated. Also, the addition of aqueous acid to IL containing actinide …

Neoglycoproteins As Potential Biomarkers And Vaccines For Chagas Disease, Elisa Garcia Carvajal

Open Access Theses & Dissertations

Trypanosoma cruzi, the causal agent of Chagas disease (CD), currently affects 6-8 million people worldwide, predominantly in Latin America, where the parasite is endemic. The treatment of CD is based on two drugs, benznidazole (BZN) and nifurtimox (NFX). These drugs cause adverse effects and are more effective in the acute phase of the disease. Conventional serology assays can be used for diagnosis, but they are not suitable for determining chemotherapy effectiveness because patients take approximately 10-20 years to exhibit negative seroconversion. Although CD has become a global health problem, specific biomarkers are still needed for the follow-up of chemotherapy and …

The Ability Of Sweat And Buffer Solutions To Reduce Hexavalent Chromium Of Relevance For Leather Extraction, Alexandra Wright, Lila Laundry-Mottiar, Yolanda Hedberg

Chemistry Publications

The European Union restricted the amount of hexavalent chromium (Cr(VI)) in leather in 2015, but skin allergy cases due to Cr-tanned leather are not declining. Standardized extraction methods have been criticized to both over- and underestimate the expected amount of bioavailable Cr(VI) in leather. This study aims to evaluate the ability of four extraction solutions to reduce or preserve Cr(VI): artificial sweat solutions (ASWs) of pH 4.7, 6.5, and 8.0, and phosphate buffer (PB) of pH 8.0. This was investigated by incubating each solution with added Cr(VI) as a function of time, and then measuring the recovered Cr(VI). All solutions, …

Polynorbornenes For Advanced Applications And Processes, Xinyi Wang

Doctoral Dissertations

Polynorbornenes have dramatically different properties and various applications depending on their chemical structures. The modular nature of norbornene-based systems provides a facile route toward synthesizing diverse polymeric materials, thus making them ideal materials for systematic structure-property investigations. Herein, their application as gas separation membranes and the correlation between their gas-transport properties and polymer structures will be investigated. Though many valuable correlations between gas-permeability and polynorbornene structure have been studied previously, many of these efforts have focused heavily on designing materials with various chemical structures to achieve high permeabilities. In contrast, the influence of molecular structure on: a) polynorbornene chain packing …

Synthesis And Processing Of Polymeric Materials For Hydrogen Storage, Dominic Adrewie

Theses and Dissertations

Hydrogen is one of the most promising alternatives and clean fuel sources, but it has faced several hurdles due to storage and transportation issues. Several methods have been proposed, developed, and are being improved. Key among these is the use of polymers as safe hydrogen storage media.

This work investigated the polymerization of methyl vinyl ketone using different concentrations 2,2’-Azobis(2-methylpropionitrile) as the initiator in a free radical polymerization mechanism. There was a subsequent analysis of the effect of the initiator concentration on the conversion rate and the molecular weight of the polymers produced with the help of Gel permeation chromatography. …

Pesticide-Leaf Interactions And Their Implications For Pesticide Fate Modeling, Ashlie Kinross

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work described here provides measured data to improve the understanding of the interaction between a pesticide and leaf surface after application. Two methods were developed, one using a newly introduced instrument, for the extraction of pesticides from leaves. This is required to measure the concentration of pesticide in the leaves. Using one of the developed extraction methods, measurements were made to determine how a pesticide equilibrates between a leaf and the air above it. These measurements were incorporated into a pesticide fate model that predicts how a pesticide moves through the environment after application to an agricultural field. The …

Catalytic Activity Of Tungsten-Dioxo And Tungsten-Diimido Complexes, Kayla Denike

Graduate Theses and Dissertations

Due to the significant decline in the availability of petrochemical resources and the increasing demand for the useful olefin mixtures extracted from oil, a sustainable and efficient alternative to these materials has become vital. Fortunately, renewable biomass derived materials may serve as a sustainable solution to the limited resources problem. Molecules derived from the degradation of biomasses are highly oxygenated and highly functionalized. Developing processes to efficiently defunctionalize these oxygen-rich materials will lead to potential up-conversion to carbon chemicals. Homogeneous catalytic deoxygenation processes present an opportunity to access valuable carbon commodity chemicals from biomass derived polyols. This dissertation details the …

A Comprehensive Review On The Diverse Pharmacological Perspectives Of Terminalia Chebula Retz, Md. Rakibul Hassan Bulbul, Mohammad Nizam Uddin Chowdhury, Taslima Anjum Naima, Md. Shakil Imtiaj, Nazmul Huda, Md. Giash Uddin

Chemistry Faculty Publications and Presentations

Terminalia chebula Retz, commonly known as ‘Haritaki/Myrobalan,’ has been utilised as a traditional medicine for a long time. It has been extensively exercised in various indigenous medicine practices like Unani, Tibb, Ayurveda, and Siddha to remedy human ailments such as bleeding, carminative, dysentery, liver tonic, digestive, antidiarrheal, analgesic, anthelmintic, antibacterial and helpful in skin disorders. Studies on the pharmacological effects of T. chebula and its phytoconstituents documented between January, 1996 and December, 2021 were explored using various electronic databases. During the time mentioned above, several laboratory approaches revealed the biological properties of T. chebula, including antioxidative, antiproliferative, anti-microbial, proapoptotic, …

Driving Piezochromism And Metallicity In Van Der Waals Materials Under Compression, Nathan Harms

Doctoral Dissertations

Complex chalcogenides provide an important platform to explore the interplay between structure, charge, and spin across pressure-induced phase transitions. Where much of the previous research has been focused on tuning these materials towards the single-layer limit, we instead explore the modification of bond lengths and bond angles under compression. In the first project we revealed piezochromism in MnPS₃. We combined high pressure optical spectroscopy and first-principles calculations to analyze the dramatic color change (green → yellow → red → black) that takes place as the charge gap shifts across the visible and into the near infrared region, moving …

Cobalt Telluride Electrocatalyst For Selective Electroreduction Of Co2 To Value-Added Chemicals, Apurv Saxena, Harish Singh, Manashi Nath

Chemistry Faculty Research & Creative Works

Recent emphasis on carbon dioxide utilization has necessitated the exploration of different catalyst compositions other than copper-based systems that can significantly improve the activity and selectivity towards specific CO₂ reduction products at low applied potential. In this study, a binary CoTe has been reported as an efficient electrocatalyst for CO₂ reduction in aqueous medium under ambient conditions at neutral pH. CoTe showed high Faradaic efficiency and selectivity of 86.83 and 75%, respectively, for acetic acid at very low potential of − 0.25 V vs RHE. More intriguingly, C1 products like formic acid was formed preferentially at slightly higher …

Mercury Methylation Potentials In Sediments Of An Ancient Cypress Wetland Using Species-Specific Isotope Dilution Gc-Icp-Ms, Derek D. Bussan, Chris Douvris, James V. Cizdziel

Faculty and Student Publications

Wetlands are of a considerable environmental value as they provide food and habitat for plants and animals. Several important chemical transformations take place in wetland media, including the conversion of inorganic mercury (Hg) to monomethylmercury (MeHg), a toxic compound with a strong tendency for bioconcentration. Considering the fact that wetlands are hotspots for Hg methylation, we investigated, for the first time, Hg methylation and demethylation rates in an old growth cypress wetland at Sky Lake in the Mississippi Delta. The Sky Lake ecosystem undergoes large-scale water level fluctuations causing alternating periods of oxic and anoxic conditions in the sediment. These …

Identification And Quantitation Of Unspecified Impurities Discovered In Novel Oral Irinotecan By Lc-Ms/Ms And Uhplc, Laura B. Miller

Forensic Science Master's Projects

Irinotecan is a cancer medication approved for medical use in the United States in 1996. It is currently administered via intravenous injection. However, intravenous dosing has disadvantages such as requirement of administration by a trained professional in a medical facility, possible severe adverse effects, pain at the injection site, and possible hemolysis if injected too rapidly. Previously oral administration was not feasible because the p-glycoprotein (p-GP) on the cell membrane of stomach cells acts as a defense mechanism against harmful substances by pumping the irinotecan back into the intestinal lumen for excretion. With the discovery of the p-GP inhibitor encequidar …

Amyloid Fibril Formation And Polymorphism : A Critical Role Of Sulfur-Containing Amino Acid Residues, Tatiana Quiñones-Ruiz

Legacy Theses & Dissertations (2009 - 2024)

Protein aggregation that results in the formation of amyloid fibrils has been linked to many neurodegenerative disorders, including Alzheimer’s disease and Parkinson’s disease. The sulfur atoms in methionine (Met) and cysteine (Cys) residues of proteins can be readily oxidized, significantly affecting their properties. Oxidation of sulfur-containing amino acids has recently been shown to affect protein fibrillation. This work presents novel findings on Cys and Met redox reactions that are related to the formation of amyloid fibrils and on the polymorphism of a model fibrillogenic protein, hen egg white lysozyme (HEWL). Biophysical techniques including Raman spectroscopy, atomic force microscopy, electron paramagnetic …

Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj

Electronic Theses and Dissertations

Bis(thiosemicarbazones) (BTSCs) and their metal complexes have been extensively studied for various applications including catalysis for hydrogen evolution reactions, treatment of neurodegenerative diseases, hypoxia imaging, and a wide range of pharmacological purposes including antitumor, antiviral, antibacterial, and antifungal agents. The paramount property that makes BTSC metal complexes interesting for their use in these applications is the reduction potential of the coordinated metal, which can be selectively tuned by varying the substituents present on the ligand framework. Although the BTSCs have shown a great deal of success as potential cancer therapeutic agents, they lack selectivity towards cancer cells. For this matter, …