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Full-Text Articles in Chemistry

Synthesis, Characterization, And Cytotoxicity Studies Of A Copper(Ii) Complex With Vanillin 3-Ethyl-Thiosemcarbazone A Ligand, Novia Mann, Ifeoluwa Oyeyemi, Duaa R. Alajroush, Elizabeth A. Tonsel-White, Stephen J. Beebe, Alvin Holder Mar 2023

Synthesis, Characterization, And Cytotoxicity Studies Of A Copper(Ii) Complex With Vanillin 3-Ethyl-Thiosemcarbazone A Ligand, Novia Mann, Ifeoluwa Oyeyemi, Duaa R. Alajroush, Elizabeth A. Tonsel-White, Stephen J. Beebe, Alvin Holder

Undergraduate Research Symposium

Triple-negative breast cancer (TNBC) is one of the most aggressive and challenging breast cancer subtypes to treat, as these cancer cells lack three common receptors: estrogen, progesterone, and human epidermal growth factor receptor 2. The multiple oxidation states transition metals can occupy have made this narrowly explored group popular for anti-cancer research in recent decades. Furthermore, the success of cisplatin, which has platinum as a metal center, while being a cancer-fighting agent with serious side effects, has caused other metal centers to be investigated as possible alternatives as chemotherapeutic drugs. Copper, as a biologically essential metal, makes an attractive candidate …


Apkcs Role In Neuroblastoma Cell Signaling Cascades And Implications Of Apkcs Inhibitors As Potential Therapeutics, Sloan Breedy Mar 2023

Apkcs Role In Neuroblastoma Cell Signaling Cascades And Implications Of Apkcs Inhibitors As Potential Therapeutics, Sloan Breedy

USF Tampa Graduate Theses and Dissertations

Neuroblastoma (NB) is a cancer that develops in the neuroblasts. It is the most common cancer in children under the age of 1 year, accounting for approximately 6% of all cancers. The prognosis of NB is linked to both age and degree of cell differentiation. This results in a range of survival rates for patients, with outcomes ranging from recurrence and mortality to high survival rates and tumor regression. Our previous work indicated that PKC-ι promotes cell proliferation in NB cells through the PKC-ι/Cdk7/Cdk2 cascade. We report on two atypical protein kinase inhibitors as potential therapeutic candidates against BE(2)-C and …


In Silico Binding Of 2-Aminocyclobutanones To Sars-Cov-2 Nsp13 Helicase And Demonstration Of Antiviral Activity, Thahani S. Habeeb Mohammad, Yash Gupta, Cory T. Reidl, Vlad Nicolaescu, Haley Gula, Ravi Durvasula, Prakasha Kempaiah, Daniel P. Becker Ph.D. Mar 2023

In Silico Binding Of 2-Aminocyclobutanones To Sars-Cov-2 Nsp13 Helicase And Demonstration Of Antiviral Activity, Thahani S. Habeeb Mohammad, Yash Gupta, Cory T. Reidl, Vlad Nicolaescu, Haley Gula, Ravi Durvasula, Prakasha Kempaiah, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

The landscape of viral strains and lineages of SARS-CoV-2 keeps changing and is currently dominated by Delta and Omicron variants. Members of the latest Omicron variants, including BA.1, are showing a high level of immune evasion, and Omicron has become a prominent variant circulating globally. In our search for versatile medicinal chemistry scaffolds, we prepared a library of substituted α-aminocyclobutanones from an α-aminocyclobutanone synthon (11). We performed an in silico screen of this actual chemical library as well as other virtual 2-aminocyclobutanone analogs against seven SARS-CoV-2 nonstructural proteins to identify potential drug leads against SARS-CoV-2, and more broadly against coronavirus …


College Of Natural Sciences Newsletter, February 2023, College Of Natural Sciences Mar 2023

College Of Natural Sciences Newsletter, February 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 4, Issue 1

Page 1 Dean's Message
Page 2 Awards and Recognition
Page 3-4 Nobel Recipient Visits Campus
Page 4 Adopting the Pantry
Page 5 Growing a Recruitment Mindset
Page 6 February Outreach Events
Page 7 Media Coverage of CNS
Page 8 Open PRAIRIE Data
Page 9 54th Geography Convention, and Tom Loveland EROS Geography Scholarship
Page 10 Photos of Dr. Carolyn Bertozzi's Visit


Ultrasound-Assisted Air-Jet Spinning Of Silk Fibroin-Soy Protein Nanofiber Composite Biomaterials., Futian Yang, Fang Wang, Janine Mazahreh, Xiao Hu Feb 2023

Ultrasound-Assisted Air-Jet Spinning Of Silk Fibroin-Soy Protein Nanofiber Composite Biomaterials., Futian Yang, Fang Wang, Janine Mazahreh, Xiao Hu

College of Science & Mathematics Departmental Research

Ultrasound utilizes a non-radiation technology that can meet modern standards to gain access to cheap, reliable and sustainable modern energy. Ultrasound technology can be implemented in the field of biomaterials for its exceptional potential in controlling the shape of nanomaterials. This study presents the first example of the production of soy and silk fibroin protein composite nanofibers in various ratios via combining ultrasonic technology with air-spray spinning. Characterization of ultrasonic spun nanofibers was performed by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, water contact angle, water retention, enzymatic …


Solvatochromic Behavior Of 2,7-Disubstituted Sila- And Germafluorenes, Shelby J. Jarrett-Noland, William Mcconnell, Janet Braddock-Wilking, Cynthia M. Dupureur Feb 2023

Solvatochromic Behavior Of 2,7-Disubstituted Sila- And Germafluorenes, Shelby J. Jarrett-Noland, William Mcconnell, Janet Braddock-Wilking, Cynthia M. Dupureur

Educator Preparation & Leadership Faculty Works

Push–pull dyes exhibit intramolecular charge transfer behavior, which due to changes in the dipole moment upon excitation, is the origin of their sensitivity to the environment. Such compounds are of interest as probes for bioimaging and as biosensors to monitor cellular dynamics and molecular interactions. Desirable biological probes absorb in the visible region, have high extinction coefficients, high quantum yield and excellent photostability. Fluorophores with scaffolding that can be used to tune and optimize solvatochromic behavior are of particular interest. Here, we investigate the environmental sensitivity of a small library of highly fluorescent 2,7-disubstituted sila- and germafluorenes. Density functional theory …


Development Of An Lcms Method To Detect And Quantify Curcumin In A Novel Oral Formulation Of Turmeric, Brandon Renninger Feb 2023

Development Of An Lcms Method To Detect And Quantify Curcumin In A Novel Oral Formulation Of Turmeric, Brandon Renninger

Annual Research Symposium

No abstract provided.


Preparation And Characterization Of Salvia Triloba Extract And Evaluation Of Its Cytotoxic Effect On Bone Cancer Cell Line, Basma Hossam Abdelmonem Feb 2023

Preparation And Characterization Of Salvia Triloba Extract And Evaluation Of Its Cytotoxic Effect On Bone Cancer Cell Line, Basma Hossam Abdelmonem

Theses and Dissertations

Background: Osteosarcoma is a tumor of mesenchymal origin characterized by uncontrolled production of immature osteoid tissue. It is more common in children and adults over the age of 65. Many studies reported the cytotoxic effect of many plant extracts, including Salvia triloba, on different cancer cell lines when used alone or in combination with other chemotherapeutic agents.

Methods: In our study, the methanolic extract obtained from the air-dried leaves of Salvia triloba leaves from Palestine was screened for its total phenolic and flavonoid contents. The major components of phenolics and flavonoids were detected using LC-QToF-MS technique. The two phenolics …


College Of Natural Sciences Newsletter, November 2022 - January 2023, College Of Natural Sciences Feb 2023

College Of Natural Sciences Newsletter, November 2022 - January 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volme 3, Issue 7

Page 1 Dean's Message
Page 2 Awards & Recognition
Page 3 Sioux Falls Middle School Visit
Page 4 Bio-Micro Day of Scholars
Page 5 GIS Day at USGS EROS
Page 6 Indigenous People's Festival, & Visiting Jack's Imagination Lab
Page 7 Media Coverage of CNS, & Research Highlights from Geography & Geospatial Sciences
Page 8 Media Coverage of CNS. cont.
Page 9 Open PRAIRIE Data
Page 10 Recent Publications from CNS
Page 11 Recent Publications from CNS. cont.
Page 12 CNS Holiday Snapshots
Page 13 & 14 Fall 2022 Dean's List
Page 12-14 Fall 2022 Outreach …


Clic And Membrane Wound Repair Pathways Enable Pandemic Norovirus Entry And Infection, B. Vijayalakshmi Ayyar, Khalil Ettayebi, Wilhelm Salmen, Umesh C. Karandikar, Frederick H. Neill, Victoria R. Tenge, Sue E. Crawford, Erhard Bieberich, B. V. Venkataram Prasad, Robert L. Atmar, Mary K. Estes Feb 2023

Clic And Membrane Wound Repair Pathways Enable Pandemic Norovirus Entry And Infection, B. Vijayalakshmi Ayyar, Khalil Ettayebi, Wilhelm Salmen, Umesh C. Karandikar, Frederick H. Neill, Victoria R. Tenge, Sue E. Crawford, Erhard Bieberich, B. V. Venkataram Prasad, Robert L. Atmar, Mary K. Estes

Markey Cancer Center Faculty Publications

Globally, most cases of gastroenteritis are caused by pandemic GII.4 human norovirus (HuNoV) strains with no approved therapies or vaccines available. The cellular pathways that these strains exploit for cell entry and internalization are unknown. Here, using nontransformed human jejunal enteroids (HIEs) that recapitulate the physiology of the gastrointestinal tract, we show that infectious GII.4 virions and virus-like particles are endocytosed using a unique combination of endosomal acidification-dependent clathrin-independent carriers (CLIC), acid sphingomyelinase (ASM)-mediated lysosomal exocytosis, and membrane wound repair pathways. We found that besides the known interaction of the viral capsid Protruding (P) domain with host glycans, the Shell …


Engineered Plga Nanofibers For Drug Delivery, Andrew Mancuso Feb 2023

Engineered Plga Nanofibers For Drug Delivery, Andrew Mancuso

Dissertations, Theses, and Capstone Projects

Poly-lactic-co-glycolic acid (PLGA) polymers are rapidly gaining momentum as a platform for next-generation drug delivery systems due to their ease and low cost of synthesis, favorable biocompatibility and biodegradability, and lack of toxicity. In particular, the application of drug-loaded PLGA nanofibers directly to a target tissue may represent a promising alternative to traditional routes of drug administration (e.g., oral, injectable) as they offer the potential to greatly improve bioavailability, increase efficacy, and reduce off-target toxicity. Furthermore, the use of such a system may potentially allow for greater flexibility in clinical drug development, by enabling the use of compounds which have …


Essential Oils Composition And Biological Activity Of Chamaecyparis Obtusa, Chrysopogon Nigritanus And Lavandula Coronopifolia Grown Wild In Sudan, Loai M H Eltayeb, Sakina Yagi, Hanan M M Mohamed, Gokhan Zengin, Mohammad Ali Shariati, Maksim Rebezov, Abdullah Ibrahim Uba, Jose Manuel Lorenzo Jan 2023

Essential Oils Composition And Biological Activity Of Chamaecyparis Obtusa, Chrysopogon Nigritanus And Lavandula Coronopifolia Grown Wild In Sudan, Loai M H Eltayeb, Sakina Yagi, Hanan M M Mohamed, Gokhan Zengin, Mohammad Ali Shariati, Maksim Rebezov, Abdullah Ibrahim Uba, Jose Manuel Lorenzo

College of Science & Mathematics Departmental Research

Generally, there are scant data about the constituents and eventually the biological activity of essential oils (EOs) from aromatic plants that grow naturally in Sudan. The present study aimed to determine the chemical composition, and antioxidant and enzyme inhibitory activities of EO extracted from the fruit of Chamaecyparis obtusa (Siebold and Zucc.) Endl. (family Cupressaceae), root of Chrysopogon nigritanus (Benth.) Veldkampis (family Poaceae) and aerial part of Lavandula coronopifolia Poir (family Lamiaceae). The fruit of C. obtusa contained only monoterpenes, mainly hydrogenated ones, with α-pinene (69.07%) as the major component. Oxygenated sesquiterpenes comprised the highest content of the C. nigritanus …


The Effects Of Salinity And Acetaminophen On The Aquatic Snail Physa Acuta, Michelle Sackey-Ansah, Megan Mackey, Daniel Elias, Jason Doll, Alyssa Brookhart Jan 2023

The Effects Of Salinity And Acetaminophen On The Aquatic Snail Physa Acuta, Michelle Sackey-Ansah, Megan Mackey, Daniel Elias, Jason Doll, Alyssa Brookhart

Journal of the South Carolina Academy of Science

Pharmaceuticals are increasingly detected in water bodies, and their presence can negatively impact aquatic organisms. This effect can be amplified when combined with increasing salinity in freshwater ecosystems. Acetaminophen is a widely used analgesic that is commonly found in river, streams, and waters where it is discharged directly. Therefore, organisms present in these locations (e.g., insects, snails, amphibians, and fish) are likely to be affected by acetaminophen. In this study, we determined the effects of elevated salinity (0.68 g/L), acetaminophen (500 µg/L) and combined elevated salinity (0.68 g/L) and acetaminophen (500 µg/L), on the growth, reproduction, and movement of the …


Bitumen Aging—Laboratory Simulation Methods Used In Practice And Selected Directions Of Research On New Methods, Paweł Czajkowski, Andrzej Przyjazny, Grzegorz Boczkaj Jan 2023

Bitumen Aging—Laboratory Simulation Methods Used In Practice And Selected Directions Of Research On New Methods, Paweł Czajkowski, Andrzej Przyjazny, Grzegorz Boczkaj

Natural Sciences Publications

Changes in the properties of bitumen binders that occur as a result of aging have a huge impact on the durability of products produced from them. In particular, asphalt pavements, which constitute the most common use of petroleum bitumen, are susceptible to damage resulting from the increasing stiffness of the bitumen during its life cycle. Increased stiffness of asphalt pavements reduces the pavement resistance to low-temperature cracks and fatigue cracks, ultimately leading to the loss of their functional properties and the need for road repair. The rate of changes in bitumen properties is influenced by many factors, the most important …


Dinitrogen Emissions Dominate Nitrogen Gas Emissions From Soils With Low Oxygen Availability In A Moist Tropical Forest, Maya Almaraz, Peter M. Groffman, Whendee L. Silver, Steven J. Hall, Yang Lin, Christine S. O'Connell, Stephen Porder Jan 2023

Dinitrogen Emissions Dominate Nitrogen Gas Emissions From Soils With Low Oxygen Availability In A Moist Tropical Forest, Maya Almaraz, Peter M. Groffman, Whendee L. Silver, Steven J. Hall, Yang Lin, Christine S. O'Connell, Stephen Porder

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Lowland tropical forest soils are relatively N rich and are the largest global source of N2O (a powerful greenhouse gas) to the atmosphere. Despite the importance of tropical N cycling, there have been few direct measurements of N2 (an inert gas that can serve as an alternate fate for N2O) in tropical soils, limiting our ability to characterize N budgets, manage soils to reduce N2O production, or predict the future role that N limitation to primary productivity will play in buffering against climate change. We collected soils from across macro- and micro-topographic gradients …


Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd Jan 2023

Dual Ionic Liquid-Functionalized Cellulosic Materials: Thermal, Mechanical And Conductive Properties, Elizabeth Mcgrew, Kevin M. Miller Phd

Posters-at-the-Capitol

Cellulose, an inexpensive and renewable biomacromolecule, represents an intriguing synthetic foundation for new materials with task-specific properties. Here, we wish to report a synthetic route for functionalizing cellulose with a side chain containing two ionic liquid functional groups using azide-alkyne ‘click’ cyclization strategy, followed by quaternization of the two resulting heterocycles (1,2,3-triazole and imidazole). Through this functionalization strategy, the resulting cellulosic materials exhibited significant softening, with several glass transition (Tg) values observed below room temperature, indicating the amorphous nature of the materials, with the Tg dependent on both the length of the side chain and the …


Mechanistic Insights Into Mftr-Dependent Regulation Of The Redox Cofactor Mycofactocin, Aigera Mendauletova Jan 2023

Mechanistic Insights Into Mftr-Dependent Regulation Of The Redox Cofactor Mycofactocin, Aigera Mendauletova

Electronic Theses and Dissertations

Organic redox cofactors are essential for life. While classic flavins and nicotinamides are widely distributed across all domains of life, nature has also evolved niche cofactors in subsets of life domains. For example, in Actinobacteria, coenzyme F420 is commonly used in place of flavin mononucleotide in enzymes associated with carbon fixation and oxidation of secondary alcohols. The importance of niche cofactors has long been recognized however, detailed understanding about their biosynthesis and physiological uses has been lagging. One class of niche cofactors is derived from ribosomally synthesized and posttranslationally modified peptides (RiPPs). To achieve their mature form, the genetically …


Post-Translational Modification Of Proteins Via Ambient Air Pollutants And Endogenous Reactive Species, Rachel Lauren Davey Jan 2023

Post-Translational Modification Of Proteins Via Ambient Air Pollutants And Endogenous Reactive Species, Rachel Lauren Davey

Electronic Theses and Dissertations

Proteins can react with reactive oxygen species (ROS) and reactive nitrogen species (RNS) to form post-translational modifications (PTMs), which can affect protein structure and function. The formation of 3-nitrotyrosine (NTyr) and dityrosine (DiTyr) upon reaction of proteins with ROS/RNS are two common PTMs studied due to their stability and irreversibility, as well as their ability to enhance the allergenicity of pollen allergens upon formation. Many common techniques used to study the formation of these PTMs can reliably detect the PTMs but can only provide semi-quantitative information due to many assumptions and limitations. In Chapter 2 we present an analysis of …


Novel Application Of Graphene Oxide In Conjunction With Dna Binding Dcas9 For Detecting Antibiotic Resistance Genes, Langley Williams Jan 2023

Novel Application Of Graphene Oxide In Conjunction With Dna Binding Dcas9 For Detecting Antibiotic Resistance Genes, Langley Williams

Mahurin Honors College Capstone Experience/Thesis Projects

The frequent emergence of antibiotic resistance genes poses a stumbling block to prompt treatment of pathogen-originating diseases and therefore spurs the demand for a simple, rapid diagnostic device that can outcompete the time and cost of traditional methods such as PCR and cell culturing. The proposed method for detecting pathogenic DNA utilizes the binding properties of deactivated CRISPR-associated protein9 (dCas9) complexed with fluorescein-labeled single-guide RNA (sgRNA) and the fluorescence quenching properties previously demonstrated in graphene oxide (GO). For our assay, we designed sgRNAs to target specific 20 nucleotide sequences extracted from the tetracycline resistance (tetM) gene sequence and covalently modified …


Chemistry And Public Policy: Equipping Advocates, Herbert R. Fynewever, I. Bos, C. Demlow, G. Fulkerson Jan 2023

Chemistry And Public Policy: Equipping Advocates, Herbert R. Fynewever, I. Bos, C. Demlow, G. Fulkerson

Summer Research

No abstract provided.


High Order Structures Formed By The Natural Aromatic Amino Acids, Gabriel Alexander Kupovics, Zeina Alraawi Jan 2023

High Order Structures Formed By The Natural Aromatic Amino Acids, Gabriel Alexander Kupovics, Zeina Alraawi

Inquiry: The University of Arkansas Undergraduate Research Journal

Excessive concentrations of the natural aromatic amino acids phenylalanine and tyrosine are characteristic of the severe genetic abnormalities known as phenylketonuria (PKU) and tyrosinemia, respectively. Within this context, this feature article authenticates claims that tryptophan can form amyloid-like supramolecular structures in vitro and is the first to propose potential mechanisms of tryptophan self-assembly, including hydrophobic and electrostatic interactions. Thioflavin T (ThT) fluorescence kinetics and transmission electron microscopy (TEM) data suggest the formation of amyloid-like fibrillar structures by natural aromatic amino acids in vitro. Additionally, the propensity of amino acid aggregation increases in the presence of sodium dodecyl sulfate (SDS). The …


Identification Of Rickettsia Prowazekii Methionine Aminopeptidase Inhibitors And Development Of Thermal Shift Assays For Burkholderia Pseudomallei Ispf And Sars-Cov-2 3cl Protease, Ishpriya Sharma Jan 2023

Identification Of Rickettsia Prowazekii Methionine Aminopeptidase Inhibitors And Development Of Thermal Shift Assays For Burkholderia Pseudomallei Ispf And Sars-Cov-2 3cl Protease, Ishpriya Sharma

Graduate Research Theses & Dissertations

There is a crucial need for new antibacterial agents to combat the increase in antibiotic resistance. Methionine aminopeptidase (MetAp) is an enzyme that removes the amino-terminal methionine residue from newly synthesized proteins, an important step in the maturation of proteins. As such, MetAp is a target for the development of antibacterial and anticancer agents. One such bacterial target is Rickettsia prowazekii (Rp), the causative agent of epidemic typhus. To discover new inhibitors of RpMetAp1, the MMV Malaria Box, which is a collection of 400 compounds with drug-like and probe-like compounds, was screened using a high throughput fluorescence-based RpMetAp1 enzyme inhibition …


Structure–Activity Relationship Studies On 6-Chloro-1-Phenylbenzazepines Leads To The Identification Of A New Dopamine D1 Receptor Antagonist, Rajan Giri, Hari K. Namballa, Vishwashiv Emogaje, Wayne W. Harding Jan 2023

Structure–Activity Relationship Studies On 6-Chloro-1-Phenylbenzazepines Leads To The Identification Of A New Dopamine D1 Receptor Antagonist, Rajan Giri, Hari K. Namballa, Vishwashiv Emogaje, Wayne W. Harding

Publications and Research

The 1-phenylbenzazepine template has yielded a number of D1R-like ligands, which, though useful as pharmacological tools, have significant drawbacks in terms of selectivity versus D5R as well as pharmacokinetic behavior. A number of 1-phenylbenzazepines contain a 6-chloro functional group, but extensive SAR studies around the 6-chloro-1-phenylbenzazepine framework have not been reported in the literature. To further understand the tolerance of the 6-chloro-1-phenylbenzazepine template for various substituent groups towards affinity and selectivity at D1R, we synthesized two series of analogs with structural variations at the C-7, C-8, N-3, C-3′ and C-4′ positions. The series 2 analogs differed from …


Potential Interactions Between Diatoms And Bacteria Are Shaped By Trace Element Gradients In The Southern Ocean, Alexa R. Sterling, Laura Z. Holland, Randelle M. Bundy, Shannon M. Burns, Kristen N. Buck, P. Dreux Chappell, Bethany D. Jenkins Jan 2023

Potential Interactions Between Diatoms And Bacteria Are Shaped By Trace Element Gradients In The Southern Ocean, Alexa R. Sterling, Laura Z. Holland, Randelle M. Bundy, Shannon M. Burns, Kristen N. Buck, P. Dreux Chappell, Bethany D. Jenkins

OES Faculty Publications

The growth of diatoms in the Southern Ocean, especially the region surrounding the West Antarctic Peninsula, is frequently constrained by low dissolved iron and other trace metal concentrations. This challenge may be overcome by mutualisms between diatoms and co-occurring associated bacteria, in which diatoms produce organic carbon as a substrate for bacterial growth, and bacteria produce siderophores, metal-binding ligands that can supply diatoms with metals upon uptake as well as other useful secondary compounds for diatom growth like vitamins. To examine the relationships between diatoms and bacteria in the plankton (diatom) size class (> 3 mu m), we sampled both …


Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams Jan 2023

Atmospheric Input And Seasonal Inventory Of Dissolved Iron In The Sargasso Sea: Implications For Iron Dynamics In Surface Waters Of The Subtropical Ocean, Peter N. Sedwick, Bettina M. Sohst, K. N. Buck, S. Caprara, R. J. Johnson, D. C. Ohnemus, L. E. Sofen, A. Tagliabue, B. S. Twining, Tara E. Williams

OES Faculty Publications

Constraining the role of dust deposition in regulating the concentration of the essential micronutrient iron in surface ocean waters requires knowledge of the flux of seawater-soluble iron in aerosols and the replacement time of dissolved iron (DFe) in the euphotic zone. Here we estimate these quantities using seasonally resolved DFe data from the Bermuda Atlantic Time-series Study region and weekly-scale measurements of iron in aerosols and rain from Bermuda during 2019. In response to seasonal changes in vertical mixing, primary production and dust deposition, surface DFe concentrations vary from ∼0.2 nM in early spring to >1 nM in late summer, …


Isotopic Evidence For Sources Of Dissolved Carbon And The Role Of Organic Matter Respiration In The Fraser River Basin, Canada, Britta M. Voss, Timothy I. Eglinton, Bernhard Peucker-Ehrenbrink, Valier Galy, Susan Q. Lang, Cameron Mcintyre, Robert G.M. Spencer, Ekaterina Bulygina, Zhaohui Aleck Wang, Katherine A. Guay Jan 2023

Isotopic Evidence For Sources Of Dissolved Carbon And The Role Of Organic Matter Respiration In The Fraser River Basin, Canada, Britta M. Voss, Timothy I. Eglinton, Bernhard Peucker-Ehrenbrink, Valier Galy, Susan Q. Lang, Cameron Mcintyre, Robert G.M. Spencer, Ekaterina Bulygina, Zhaohui Aleck Wang, Katherine A. Guay

OES Faculty Publications

Sources of dissolved and particulate carbon to the Fraser River system vary significantly in space and time. Tributaries in the northern interior of the basin consistently deliver higher concentrations of dissolved organic carbon (DOC) to the main stem than other tributaries. Based on samples collected near the Fraser River mouth throughout 2013, the radiocarbon age of DOC exported from the Fraser River does not change significantly across seasons despite a spike in DOC concentration during the freshet, suggesting modulation of heterogeneous upstream chemical and isotopic signals during transit through the river basin. Dissolved inorganic carbon (DIC) concentrations are highest in …


Efficient Text Bounding Box Identification Using Mask R-Cnn: Case Of Thai Documents, Phanthakan Kiatphaisansophon Jan 2023

Efficient Text Bounding Box Identification Using Mask R-Cnn: Case Of Thai Documents, Phanthakan Kiatphaisansophon

Chulalongkorn University Theses and Dissertations (Chula ETD)

Text detection is a fundamental task in computer vision, particularly for Optical Character Recognition (OCR) application. This research focuses on text detection part of the OCR. Our previous text detection model, CRAFT (Character-Region Awareness For Text detection) has shown promising outcomes in bounding box identification. Nevertheless, it encounters issues associated with post-processing and multiline text. The post-processing related to the necessity to reconfigure the model when new documents are introduced, resulting in inefficiencies and complexities. Also the CRAFT model tends to blend bounding boxes from consecutive lines, introducing errors and impacting the accuracy in the text recognition part of the …


Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene Jan 2023

Extracting High-Molecular Weight Dna From Cyanobacteria Using Promega's Wizard® Hmw Dna Extraction Kit With A Modified Protocol, Metis, Megan A. Hept, Lesley H. Greene

Chemistry & Biochemistry Faculty Publications

Extraction of high molecular weight (HMW) DNA for long read sequencing with little to no fragmentation and high purity is difficult to acquire from cyanobacterial species. Here we describe a modified method of extraction using Promega's Wizard® HMW DNA Extraction Kit to acquire high molecular weight DNA from cyanobacterial species. The protocol used in the kit is the “3.D. Isolating HMW DNA from Gram-Positive and Gram-Negative Bacteria” protocol. During a key step in the protocol, the lingering remnants of the mucilage layer of the cyanobacterial species is removed, preventing it from sticking to the DNA pellet produced. This customized modification …


Abiotic Stress Mitigation: A Case Study From 21 Trials Using A Natural Organic Matter Based Biostimulant Across Multiple Geographies, Rachel L. Sleighter, Terry Hanson, David Holden, Kristen M. Richards Jan 2023

Abiotic Stress Mitigation: A Case Study From 21 Trials Using A Natural Organic Matter Based Biostimulant Across Multiple Geographies, Rachel L. Sleighter, Terry Hanson, David Holden, Kristen M. Richards

Chemistry & Biochemistry Faculty Publications

Crop productivity and yields can be greatly diminished by abiotic stress events including drought, extreme temperatures, excess moisture, and saline irrigation water. Multiple stressors occurring simultaneously can further exacerbate the strain on plants. Various types of biostimulants have been shown to mitigate abiotic stress and here, the results of 21 trials on corn, wheat, soybean, and various high-value crops are discussed in the context of the abiotic stress that either occurred naturally or was experimentally induced. Treatments in these trials included stressed and non-stressed plants, as well as either an untreated control or grower standard fertilizer applications alone and in …


Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey Jan 2023

Development And Biological Evaluation Of Selective Small-Molecule Inhibitors Of The Human Cytochrome P450 1b1, Austin Hachey

Theses and Dissertations--Chemistry

The human cytochrome P450 1B1 (CYP1B1) is an emerging target for small- molecule therapeutics. Several solid tumors overexpress CYP1B1 to the degree that it has been referred to as a universal tumor antigen. Conversely, its expression is low in healthy tissues. CYP1B1 may drive tumorigenesis through promoting the formation of reactive toxins from environmental pollutants or from endogenous hormone substrates. Additionally, the expression of CYP1B1 in tumors is associated with resistance to several common chemotherapies and with poor prognoses in cancer patients. However, inhibiting CYP1B1 with small molecules has been demonstrated in cellular and murine model systems to reverse this …