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Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong Oct 2020

Research Progress Of Key Components In Lithium-Sulfur Batteries, Jia-Jia Chen, Quan-Feng Dong

Journal of Electrochemistry

Due to the much higher theoretical specific capacity and energy density than the ones of traditional lithium ion battery, Li-S batteries have long been at the pinnacle in the realms of high-energy Li-metal batteries. However, the complicated electrochemical reactions on the sulfur cathode and Li anode, induced by the thermodynamic and kinetic behaviors of lithium polysulfides, are the intrinsic bottleneck to realize the full potential of Li-S batteries for practical application. In this review, we firstly discuss the roles, and thermodynamic and kinetic behaviors of polysulfides in the charging and discharging processes of Li-S batteries. Then, the functional design and …

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Synthesis, In Vitro, And In Vivo Evaluation Of Novel N-Phenylindazolyl Diarylureas As Potential Anti-Cancer Agents., Lucas N Solano, Grady L Nelson, Conor T Ronayne, Shirisha Jonnalagadda, Sravan K Jonnalagadda, Kaija Kottke, Robert Chitren, Joseph L Johnson, Manoj K Pandey, Subash C. Jonnalagadda, Venkatram R Mereddy Oct 2020

Synthesis, In Vitro, And In Vivo Evaluation Of Novel N-Phenylindazolyl Diarylureas As Potential Anti-Cancer Agents., Lucas N Solano, Grady L Nelson, Conor T Ronayne, Shirisha Jonnalagadda, Sravan K Jonnalagadda, Kaija Kottke, Robert Chitren, Joseph L Johnson, Manoj K Pandey, Subash C. Jonnalagadda, Venkatram R Mereddy

College of Science & Mathematics Departmental Research

Novel N-phenylindazole based diarylureas have been designed, synthesized and evaluated as potential anticancer agents. In vitro cell viability studies of these derivatives illustrate good potency with IC50 values in the range of 0.4–50 μM in several cancer cell lines including murine metastatic breast cancer 4T1, murine glioblastoma GL261, human triple negative breast cancer MDA-MB-231, human pancreatic cancer MIAPaCa-2, and human colorectal cancer cell line WiDr. The ester group in the lead compound 8i was modified to incorporate amino-amides to increase solubility and stability while retaining biological activity. Further in vitro studies reveal that lead candidates inhibit tube length in HUVEC …

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Graphene-Based Electrochemical Aptasensor For The Detection Of Salmonella Typhimurium, Shalini Muniandy Oct 2020

Graphene-Based Electrochemical Aptasensor For The Detection Of Salmonella Typhimurium, Shalini Muniandy

Student Works (2020-2029)

Recent foodborne outbreaks in multiple locations necessitate the continuous development of highly sensitive and specific biosensors that offer rapid and sensitive detection of foodborne pathogens. The emergence of electrochemical aptasensor which is a compact analytical device with a combination of an aptamer as the biorecognition element integrated on the transducer surface created a breakthrough in the detection of foodborne bacterial pathogens. Graphene has emerged as a promising nanomaterial for reliable detection of pathogenic bacteria due to its exceptional properties such as high electrical conductivity, large surface to volume ratio, high mechanical strength and its unique interactions with DNA bases of …

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Mutational Analysis Confirms The Presence Of Distal Inhibitor-Selectivity Determining Residues In B. Stearothermophilus Dihydrofolate Reductase, Tyler Eck, Seema Patel, Thomas Candela, Katherine Leon H, Michael Little, Natalia E. Reis, Uththara Liyanagunawardana, Ueli Gubler, Cheryl A. Janson, Jaclyn Catalano, Nina M. Goodey Oct 2020

Mutational Analysis Confirms The Presence Of Distal Inhibitor-Selectivity Determining Residues In B. Stearothermophilus Dihydrofolate Reductase, Tyler Eck, Seema Patel, Thomas Candela, Katherine Leon H, Michael Little, Natalia E. Reis, Uththara Liyanagunawardana, Ueli Gubler, Cheryl A. Janson, Jaclyn Catalano, Nina M. Goodey

Department of Chemistry and Biochemistry Faculty Scholarship and Creative Works

Many antibacterial and antiparasitic drugs work by competitively inhibiting dihydrofolate reductase (DHFR), a vital enzyme in folate metabolism. The interactions between inhibitors and DHFR active site residues are known in many homologs but the contributions from distal residues are less understood. Identifying distal residues that aid in inhibitor binding can improve targeted drug development programs by accounting for distant influences that may be less conserved and subject to frequent resistance causing mutations. Previously, a novel, homology-based, computational approach that mines ligand inhibition data was used to predict residues involved in inhibitor selectivity in the DHFR family. Expectedly, some inhibitor selectivity …

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High-Temperature Resistant Water-Soluble Polymers Derived From Exotic Amino Acids, Sumant Dwivedi, Aniruddha Nag, Shigeki Sakamoto, Yasuyoshi Funahashi, Toyohiro Harimoto, Kenji Takada, Tatsuo Kaneko Oct 2020

High-Temperature Resistant Water-Soluble Polymers Derived From Exotic Amino Acids, Sumant Dwivedi, Aniruddha Nag, Shigeki Sakamoto, Yasuyoshi Funahashi, Toyohiro Harimoto, Kenji Takada, Tatsuo Kaneko

Faculty Publications

© The Royal Society of Chemistry. High-performance water-soluble polymers have a wide range of applications from engineering materials to biomedical plastics. However, existing materials are either natural polymers that lack high thermostability or rigid synthetic polymers. Therefore, we design an amino acid-derived building block, 4,4′-diamino-α-truxillate dianion (4ATA2−), that induces water solubility in high-performance polymers. Polyimides containing 4ATA2− units are intrinsically water-soluble and are processed into films cast from an aqueous solution. The resulting polyimide films exhibit exceptional transparency and extremely high thermal stability. In addition, the films can be made insoluble in water by simple post-treatment using …

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Soft Ion Sputtering Of Pani Studied By Xps, Afm, Tof-Sims, And Sts, Christopher M. Goodwin, Zachary E. Voras, Xiao Tong, Thomas P. Beebe, Jr. Oct 2020

Soft Ion Sputtering Of Pani Studied By Xps, Afm, Tof-Sims, And Sts, Christopher M. Goodwin, Zachary E. Voras, Xiao Tong, Thomas P. Beebe, Jr.

Chemistry Faculty Publications

Herein is a study of the soft sputtering method, gas cluster ion sputtering (GCIS), and its effects on the atomic, morphologic, and band structure properties of polyaniline (PAni) as studied with X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry, atomic force microscopy, and scanning tunneling spectroscopy (STS). The GCIS source used was a 1000 argon atom cluster with 4 keV energy, which resulted in a sputter yield of 3.4 ± 0.2 × 10−3 nm3 per argon atom. Soft ion sputtering reduced the sample by explicitly removing the oxidized contaminants as determined by surface sensitive techniques: XPS and Time-of-flight secondary …

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Chemical Synthesis Of Homogeneous Human E-Cadherin N-Linked Glycopeptides: Stereoselective Convergent Glycosylation And Chemoselective Solid-Phase Aspartylation, Chen Zeng, Bin Sun, Xuefeng Cao, Joshua Zhu, Olawale Micheal Oluwadahunsi, Ding Liu, He Zhu, Jiabin Zhang, Qing Zhang, Gaolan Zhang, Christopher Andrew Gibbons, Yunpeng Liu, Jun Zhou, Peng George Wang Oct 2020

Chemical Synthesis Of Homogeneous Human E-Cadherin N-Linked Glycopeptides: Stereoselective Convergent Glycosylation And Chemoselective Solid-Phase Aspartylation, Chen Zeng, Bin Sun, Xuefeng Cao, Joshua Zhu, Olawale Micheal Oluwadahunsi, Ding Liu, He Zhu, Jiabin Zhang, Qing Zhang, Gaolan Zhang, Christopher Andrew Gibbons, Yunpeng Liu, Jun Zhou, Peng George Wang

Faculty Work Comprehensive List

We report herein an efficient chemical synthesis of homogeneous human E-cadherin N-linked glycopeptides consisting of a heptapeptide sequence adjacent to the Asn-633 N-glycosylation site with representative N-glycan structures, including a conserved trisaccharide, a core-fucosylated tetrasaccharide, and a complex-type biantennary octasaccharide. The key steps are a chemoselective on-resin aspartylation using a pseudoproline-containing peptide and stereoselective glycosylation using glycosyl fluororide as a donor. This synthetic strategy demonstrates potential utility in accessing a wide range of homogeneous N-linked glycopeptides for the examination of their biological function.

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Optimization Of Cation Exchange Chromatography Purification Of A Small Peptide: An Industrial And Practical Approach, Jamin Willoughby Oct 2020

Optimization Of Cation Exchange Chromatography Purification Of A Small Peptide: An Industrial And Practical Approach, Jamin Willoughby

Honors Theses

Ion exchange chromatography (IEX) is a common chemical separation technique that is used to separate ionizable target molecules from a liquid mixture mobile phase by adsorption of the molecule to a stationary phase. In chromatography, the stationary phase is a porous solid that the target molecule and mobile phase flows through, and is commonly referred to as the resin. Resins are commonly packed into hollow cylindrical columns. The mobile phase is the liquid solvent which flows through the column containing the stationary phase. The target molecule will have an affinity for the resin and adsorb to it, while impurities in …

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Modular Synthesis And Transition Metal-Free Alkynylation/Alkenylation Of Castagnoli–Cushmanderived N,O- And N,S-Heterocyclic Vinyl Chlorides, Timothy K. Beng, Abdikani Omar Farah, Victoria Shearer Oct 2020

Modular Synthesis And Transition Metal-Free Alkynylation/Alkenylation Of Castagnoli–Cushmanderived N,O- And N,S-Heterocyclic Vinyl Chlorides, Timothy K. Beng, Abdikani Omar Farah, Victoria Shearer

All Faculty Scholarship for the College of the Sciences

A modular and functional group-tolerant protocol for the transition metal-free coupling of novel N,O- and N,S-heterocyclic vinyl chlorides with terminal acetylenes and styrenes has been developed, leading to the epimerization-free synthesis of fully carbofunctionalized dihydro-1,4-oxazines/thiazines. Bicyclic morpholines have also been prepared through the interrogation of newly synthesized cross-conjugated dienes in Diels–Alder reactions. The use of environmentally benign reaction media endows the current strategy with a practical advantage.

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Cosore: A Community Database For Continuous Soil Respiration And Other Soil-Atmosphere Greenhouse Gas Flux Data, Ben Bond-Lamberty, Danielle S. Christianson, Avni Malhotra, Stephanie C. Pennington, Debjani Sihi, Amir Aghakouchak, Hassan Anjileli, M. Altaf Arain, Juan J. Armesto, Samaneh Ashraf, Mioko Ataka, Dennis Baldocchi, Thomas Andrew Black, Nina Buchmann, Mariah S. Carbone, Shih-Chieh Chang, Patrick Crill, Peter S. Curtis, Eric A. Davidson, Ankur R. Desai, John E. Drake, Tarek S. El-Madany, Michael Gavazzi, Carolyn-Monika Görres, Christopher M. Gough, Michael Goulden, Jillian Gregg, Omar Gutiérrez Del Arroyo, Jin-Sheng He, Takashi Hirano, Anya Hopple, Holly Hughes, Järvi Järveoja, Rachhpal Jassal, Jinshi Jian, Haiming Kan, Jason Kaye, Yuji Kominami, Naishen Liang, David Lipson, Catriona A. Macdonald, Kadmiel Maseyk, Kayla Mathes, Marguerite Mauritz, Melanie A. Mayes, Steve Mcnulty, Guofang Miao, Mirco Migliavacca, Scott Miller, Chelcy F. Miniat, Jennifer G. Nietz, Mats B. Nilsson, Asko Noormets, Hamidreza Norouzi, Christine S. O'Connell, Bruce Osborne, Cecilio Oyonarte, Zhuo Pang, Matthias Peichl, Elise Pendall, Jorge F. Perez-Quezada, Claire L. Phillips, Richard P. Phillips, James W. Raich, Alexandre A. Renchon, Nadine K. Ruehr, Enrique P. Sánchez-Cañete, Matthew Saunders, Kathleen E. Savage, Marion Schrumpf, Russell L. Scott, Ulli Seibt, Whendee L. Silver, Wu Sun, Daphne Szutu, Kentaro Takagi, Masahiro Takagi, Munemasa Teramoto, Mark G. Tjoelker, Susan Trumbore, Masahito Ueyama, Rodrigo Vargas, Ruth K. Varner, Joseph Verfaillie, Christoph Vogel, Jinsong Wang, Greg Winston, Tana E. Wood, Juying Wu, Thomas Wutzler, Jiye Zeng, Tianshan Zha, Quan Zhang, Junliang Zou Oct 2020

Cosore: A Community Database For Continuous Soil Respiration And Other Soil-Atmosphere Greenhouse Gas Flux Data, Ben Bond-Lamberty, Danielle S. Christianson, Avni Malhotra, Stephanie C. Pennington, Debjani Sihi, Amir Aghakouchak, Hassan Anjileli, M. Altaf Arain, Juan J. Armesto, Samaneh Ashraf, Mioko Ataka, Dennis Baldocchi, Thomas Andrew Black, Nina Buchmann, Mariah S. Carbone, Shih-Chieh Chang, Patrick Crill, Peter S. Curtis, Eric A. Davidson, Ankur R. Desai, John E. Drake, Tarek S. El-Madany, Michael Gavazzi, Carolyn-Monika Görres, Christopher M. Gough, Michael Goulden, Jillian Gregg, Omar Gutiérrez Del Arroyo, Jin-Sheng He, Takashi Hirano, Anya Hopple, Holly Hughes, Järvi Järveoja, Rachhpal Jassal, Jinshi Jian, Haiming Kan, Jason Kaye, Yuji Kominami, Naishen Liang, David Lipson, Catriona A. Macdonald, Kadmiel Maseyk, Kayla Mathes, Marguerite Mauritz, Melanie A. Mayes, Steve Mcnulty, Guofang Miao, Mirco Migliavacca, Scott Miller, Chelcy F. Miniat, Jennifer G. Nietz, Mats B. Nilsson, Asko Noormets, Hamidreza Norouzi, Christine S. O'Connell, Bruce Osborne, Cecilio Oyonarte, Zhuo Pang, Matthias Peichl, Elise Pendall, Jorge F. Perez-Quezada, Claire L. Phillips, Richard P. Phillips, James W. Raich, Alexandre A. Renchon, Nadine K. Ruehr, Enrique P. Sánchez-Cañete, Matthew Saunders, Kathleen E. Savage, Marion Schrumpf, Russell L. Scott, Ulli Seibt, Whendee L. Silver, Wu Sun, Daphne Szutu, Kentaro Takagi, Masahiro Takagi, Munemasa Teramoto, Mark G. Tjoelker, Susan Trumbore, Masahito Ueyama, Rodrigo Vargas, Ruth K. Varner, Joseph Verfaillie, Christoph Vogel, Jinsong Wang, Greg Winston, Tana E. Wood, Juying Wu, Thomas Wutzler, Jiye Zeng, Tianshan Zha, Quan Zhang, Junliang Zou

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Globally, soils store two to three times as much carbon as currently resides in the atmosphere, and it is critical to understand how soil greenhouse gas (GHG) emissions and uptake will respond to ongoing climate change. In particular, the soil-to-atmosphere CO2 flux, commonly though imprecisely termed soil respiration (RS), is one of the largest carbon fluxes in the Earth system. An increasing number of high-frequency RS measurements (typically, from an automated system with hourly sampling) have been made over the last two decades; an increasing number of methane measurements are being made with such systems …

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A Fuzzy Assessment Model For Hospitals Services Quality Based On Patient Experience, Mohamed Khodyer Alkafaji, Eman Salih Al-Shamery Oct 2020

A Fuzzy Assessment Model For Hospitals Services Quality Based On Patient Experience, Mohamed Khodyer Alkafaji, Eman Salih Al-Shamery

Karbala International Journal of Modern Science

The patient's experience is a lens for services assessment that provide from healthcare institutions because the patient is the first and the last recipient for the service. The patient's experience carries a lot of uncertainty and an ultimate decision cannot be taken from the patient about the services, but it carries the partial truth. Many artificial intelligence technologies deal with the concept of partial truth, such as genetic algorithms and neural networks, but the fuzzy logic remains pioneering to deal with uncertainty. This paper aims to develop an assessment model by using fuzzy inference that is able to assess the …

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Treatment Of A Worn Mineral Oil Effluent By Electrocoagulation Using Aluminium Electrodes, Serge Raoul Tchamango Dr, God Promess Lactio, Inès Estelle Nkenmogne Kamdem, Martin Benoît Ngassoum Oct 2020

Treatment Of A Worn Mineral Oil Effluent By Electrocoagulation Using Aluminium Electrodes, Serge Raoul Tchamango Dr, God Promess Lactio, Inès Estelle Nkenmogne Kamdem, Martin Benoît Ngassoum

Karbala International Journal of Modern Science

Water pollution by oils is more and more a preoccupation because of its increasing occurrence and the hazard to human life and environment. Depollution of oily effluents can sometimes generate a secondary pollution (with chemical coagulation / flocculation processes) or be very costly (ultracentrifugation). In this work, electrocoagulation with aluminium electrodes was applied to the treatment of a worn mineral oil effluent. For this to be achieved, the influence of the pH and the current density on the turbidity and organic matter was first investigated. A liquid-liquid extraction was then carried out on the oil samples in order to isolate …

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A Systematic Mapping Study On The Risk Factors Leading To Type Ii Diabetes Mellitus, Karar N. J Musafer, Fahrul Zaman Huyop, Mufeed J Ewadh, Eko Supriyanto, Mohammad Rava Oct 2020

A Systematic Mapping Study On The Risk Factors Leading To Type Ii Diabetes Mellitus, Karar N. J Musafer, Fahrul Zaman Huyop, Mufeed J Ewadh, Eko Supriyanto, Mohammad Rava

Karbala International Journal of Modern Science

Diabetes is one of the most common diseases that has had devastating effects on the general population. It is also among the most popular research trends in modern medicine. Thus, due to the complexity and desirability of this particular affliction, there is a lot of demand towards understanding this disease better, so that it can pave the way towards better solutions in combating diabetes. The aim of this review is to provide a categorization of the risk factors leading to Type II Diabetes. In order to provide a justification for the type of diabetes, an explanation is provided which covers …

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Chemical Composition And Antibacterial Activity Of The Essential Oil Of Myrtus Communis Leaves, Hajar El Hartiti, Amine El Mostaphi, Mariam Barrahi, Aouatif Ben Ali, Nabila Chahboun, Rajaa Amiyare, Abdelkader Zarrouk, Brahim Bourkhiss, Mohammed Ouhssine Oct 2020

Chemical Composition And Antibacterial Activity Of The Essential Oil Of Myrtus Communis Leaves, Hajar El Hartiti, Amine El Mostaphi, Mariam Barrahi, Aouatif Ben Ali, Nabila Chahboun, Rajaa Amiyare, Abdelkader Zarrouk, Brahim Bourkhiss, Mohammed Ouhssine

Karbala International Journal of Modern Science

The aim of this work is to determine the yield of the essential oil of the Myrtus communis leaves, to identify its chemical composition and to evaluate its antibacterial properties. The plant is harvested from Sidi Ahmed Chrif, a region in Ouazzane, Morocco. The extraction of the essential oil was carried out by hydrodistillation in a Clevenger apparatus type. The average yield was 0.7%. The analysis of this oil by Gas Chromatography coupled with Mass Spectrum (GC/MS) allows the identification of 32 compounds. Eucalyptol was the main compound with 42.43%, followed by myrtenyl acetate (21.25%) and α-pinene (19.39%). Myrtle essential …

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Hormones Of Maize Crop As Affected By Potassium Fertilization , Water Quality And Ascobin Foliar Application ., Qais Hussain Al-Samak Prof., Fatima Karim Khudair Alasadi Oct 2020

Hormones Of Maize Crop As Affected By Potassium Fertilization , Water Quality And Ascobin Foliar Application ., Qais Hussain Al-Samak Prof., Fatima Karim Khudair Alasadi

Karbala International Journal of Modern Science

A pot assay on the plastic container of the wire sunshade in the University of Kerbala's Agricultural Division was conducted to research the impact of potassium treatment, the salinity of irrigation water and ascobin sprinkling, just as their connections, on the some plant hormones activities (auxin, gibberellin and abscisic acid) in developing Zea mays crops in a soil with sandy texture during the farming fall period of 2017–2018. The trial was planned as a factorial one with three factors, Potassium adding are 0, 100 and 200 Kg K.ha–1 . the irrigation water salinity are 1, 3 and 6 ds.m …

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Editorial Board Oct 2020

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.

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Elucidating The Effect Of The Antibiotic Tetracycline On The Regulatory Function Of The Guanidine Sensing Riboswitch Ykkcd, Thomas K. Sullivan Oct 2020

Elucidating The Effect Of The Antibiotic Tetracycline On The Regulatory Function Of The Guanidine Sensing Riboswitch Ykkcd, Thomas K. Sullivan

S.U.R.E Posters

The primary objective of this research is to develop an assay – one more feasible for undergraduate institutions than currently available methods – that will enable evaluation of the concomitant binding of, guanidine and tetracycline to the ykkCD bacterial guanidine sensor riboswitch. This noncoding regulatory RNA, in addition to guanidine, also recognizes tetracycline, a translation-inhibiting antibiotic, via a high-affinity aptamer domain. The resulting conformational change by the riboswitch upregulates the expression of genes that are downstream of this regulator, most of which are membrane transporter that expel toxins from bacteria. This phenomenon exemplifies the increasing issue of bacterial antibiotic resistance, …

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Using Nucleic Acid-Gold Nanoparticle Conjugate In The Fight Against Bacteria That Are Resistant To Tetracycline Antibiotics, Allen T. Livingston Oct 2020

Using Nucleic Acid-Gold Nanoparticle Conjugate In The Fight Against Bacteria That Are Resistant To Tetracycline Antibiotics, Allen T. Livingston

S.U.R.E Posters

Antibiotic resistance is major problem in modern medicine. Seventy percent of bacterial strains are resistant to at least one antibiotic, making treatment of bacterial infections ever more expensive and difficult. Currently, we are investigating the therapeutic potency of nucleic acid-gold nanoparticle conjugates as treatments against bacteria that are resistant to the antibiotic tetracycline. We hypothesize that by attaching RNA that binds to tetracycline to silver or gold nanoparticles the resulting conjugates will work as a “Trojan-horse” tetracycline-delivery vehicle that smuggles the antibiotic into the cell without being detected by cellular defense systems. Moreover, we reason that silver or gold ions …

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Water-Soluble Graphene In Agar Gel As Electrolyte For Magnesium-Air Battery, Liew Siaw Ying Oct 2020

Water-Soluble Graphene In Agar Gel As Electrolyte For Magnesium-Air Battery, Liew Siaw Ying

Student Works (2020-2029)

Presently, ever-increasing demands on energy and the global environmental issues have given the impetus to investigate the new battery systems which are inexpensive, efficient, having high performance, and also green to the environment. Among all the battery technologies, magnesium-air (Mg-air) battery is an attractive battery to be developed owing to the interesting properties of the Mg anode. Mg has high specific energy (6.46 kWh kg-1) and reactivity, apart from its high abundance, lower cost, low toxicity, and comparatively safe to handle in the atmosphere. Nevertheless, Mg-air battery is still not being widely investigated as compared to the other batteries. Electrolyte …

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Covalent Organic Frameworks As An Organic Scaffold For Heterogeneous Catalysis Including C-H Activation, Harsh Vardhan Oct 2020

Covalent Organic Frameworks As An Organic Scaffold For Heterogeneous Catalysis Including C-H Activation, Harsh Vardhan

USF Tampa Graduate Theses and Dissertations

Linking small organic molecules into an extended solid usually afford disordered amorphous polymers. The instigation of order into such a material is of profound interest to induce inherent fine control of the overall structure. Covalent organic frameworks (COFs) are new class of porous crystalline material prepared by connecting organic building blocks via strong covalent bonds. The judicious choice of organic monomers can give rise to highly ordered and predictable frameworks with high crystallinity, surface area, and thermal/chemical stability. The role of connecting linkages such as B─O, C─C, C─N extends the principle of fundamental molecular covalent chemistry to the formation of …

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Developing Novel Tale-Based Rapid Detection Of Pathogenic Dna Utilizing 2d Graphene Oxide Nanosheets And Quantum Dots, Narayan Neupane Oct 2020

Developing Novel Tale-Based Rapid Detection Of Pathogenic Dna Utilizing 2d Graphene Oxide Nanosheets And Quantum Dots, Narayan Neupane

Masters Theses & Specialist Projects

A faster method of quantitative detection of specific dsDNA of pathogenic bacteria such as the Shiga toxin 2 gene (stx2) present in E. coli O157:H7 is of great importance. There is a need for a simple and facile method for sensitive detection of pathogenic gene which is crucial for the prevention and earlier treatment of any infectious diseases. A Transcriptional Activator-Like Effector (TALE) is a novel class of DNA-binding proteins with the unique modularity, flexibility and easy programmability compared to previously discovered DNA- binding proteins. TALEs can bind to any DNA sequences through its unique variable di- residues …

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Bentonite Reinforced Chitosan Scaffold: Effect Of Bentonite Exfoliation On Scaffold Properties, Soma Chakraborty, Cristine Joy M. Pimentel Oct 2020

Bentonite Reinforced Chitosan Scaffold: Effect Of Bentonite Exfoliation On Scaffold Properties, Soma Chakraborty, Cristine Joy M. Pimentel

Chemistry Faculty Publications

Chitosan is under investigation as biodegradable scaffolding material for tissue engineering. Crosslinked chitosan alone cannot form a self-supporting scaffold hence it needs reinforcement. The group reported fabrication of chitosan scaffolds reinforced by exfoliated and non-exfoliated bentonite and compared their properties. Scaffolds were fabricated by freeze-drying technique. Bentonite was exfoliated by allowing it to swell in water for a certain time interval. XRD profile showed that swelling reduced the crystallinity of bentonite. Both types of bentonite dispersed well in the chitosan matrix and imparted structural stability to the scaffolds. Scaffolds had interconnected pores, apparent porosity of scaffold with exfoliated bentonite was …

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All-Atomic Molecular Dynamic Studies Of Human And Drosophila Cdk8: Insights Into Their Kinase Domains, The Lxxll Motifs, And Drug Binding Site, Wu Xu, Xiao-Jun Xie, Ali K. Faust, Mengmeng Liu, Xiao Li, Feng Chen, Ashlin A. Naquin, Avery C. Walton, Peter W. Kishbaugh, Jun-Yuan Ji Oct 2020

All-Atomic Molecular Dynamic Studies Of Human And Drosophila Cdk8: Insights Into Their Kinase Domains, The Lxxll Motifs, And Drug Binding Site, Wu Xu, Xiao-Jun Xie, Ali K. Faust, Mengmeng Liu, Xiao Li, Feng Chen, Ashlin A. Naquin, Avery C. Walton, Peter W. Kishbaugh, Jun-Yuan Ji

Faculty Publications

Cyclin-dependent kinase 8 (CDK8) and its regulatory partner Cyclin C (CycC) play conserved roles in modulating RNA polymerase II (Pol II)-dependent gene expression. To understand the structure and function relations of CDK8, we analyzed the structures of human and Drosophila CDK8 proteins using molecular dynamics simulations, combined with functional analyses in Drosophila. Specifically, we evaluated the structural differences between hCDK8 and dCDK8 to predict the effects of the LXXLL motif mutation (AQKAA), the P154L mutations, and drug binding on local structures of the CDK8 proteins. First, we have observed that both the LXXLL motif and the kinase activity of CDK8 …

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Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity In Si Powders, Konstantin Tamarov, Riku Kiviluoto, Josph D. Swanson, Bret A. Unger, Alexis T. Ernst, Mark Aindow, Joakim Riikonen, Vesa-Pekka Lehto, Kurt W. Kolasinski Oct 2020

Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity In Si Powders, Konstantin Tamarov, Riku Kiviluoto, Josph D. Swanson, Bret A. Unger, Alexis T. Ernst, Mark Aindow, Joakim Riikonen, Vesa-Pekka Lehto, Kurt W. Kolasinski

Chemistry Faculty Publications

The recently discovered low-load metal-assisted catalytic etching (LL-MACE) creates nanostructured Si with controllable and variable characteristics that distinguish this technique from the conventional high-load variant. LL-MACE employs 150 times less metal catalyst and produces porous Si instead of Si nanowires. In this work, we demonstrate that some of the features of LL-MACE cannot be explained by the present understanding of MACE. With mechanistic insight derived from extensive experimentation, it is demonstrated that (1) the method allows the use of not only Ag, Pd, Pt, and Au as metal catalysts but also Cu and (2) judicious combinations of process parameters such …

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Synthesis And Design Of Novel Polymer Grafted Nanoparticles Relevant To Drug Delivery Vehicles For Biomedical Applications, Maan Abduldiyem Hassan Al-Ali Oct 2020

Synthesis And Design Of Novel Polymer Grafted Nanoparticles Relevant To Drug Delivery Vehicles For Biomedical Applications, Maan Abduldiyem Hassan Al-Ali

Theses and Dissertations

The modification of inorganic nanoparticles with organic polymer chains has become a significant field of study for the engineering of advanced nanocomposite materials. This dissertation presents the design, synthesis, and characterization of novel polymer grafted silica nanoparticles as new strategies to combat bacterial resistance. Described herein is the synthesis of monomers that have been graft polymerized onto silica nanoparticles that can be used as a delivery drug vehicle for biomedical applications. The polymerization of these monomers was performed via reversible addition-fragmentation chain transfer (RAFT) polymerization. The molecular design of the RAFT agents that are attached to the surfaces of the …

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Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic Oct 2020

Iron Speciation In Pm2.5 From Urban, Agriculture, And Mixed Environments In Colorado, Usa, Joseph R. Salazar, David J. Pfotenhauer, Frank Leresche, Fernando L. Rosario-Ortiz, Michael P. Hannigan, Sirine C. Fakra, Brian Majestic

Chemistry and Biochemistry: Faculty Scholarship

Atmospheric iron solubility varies depending on whether the particles are collected in rural or urban areas, with urban areas showing increased iron solubility. In this study, we investigate if the iron species present in different environments affects its ultimate solubility. Field data are presented from the Platte River Air Pollution and Photochemistry Experiment (PRAPPE), aimed at understanding the interactions between organic carbon and trace elements in atmospheric particulate matter (PM). 24-hr PM2.5 samples were collected during the summer and winter (2016–2017), at three different sites on the Eastern Colorado plains: an urban, agricultural, and a mixed site. Downtown Denver had …

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Pharmacologic Ire1/Xbp1s Activation Confers Targeted Er Proteostasis Reprogramming, J. M. D. Grandjean, A. Madhavan, L. Cech, B. O. Seguinot, R. J. Paxman, E. Smith, L. Scampavia, E. T. Powers, Christina B. Cooley, L. Plate, T. P. Spicer, J. W. Kelly, R. L. Wiseman Oct 2020

Pharmacologic Ire1/Xbp1s Activation Confers Targeted Er Proteostasis Reprogramming, J. M. D. Grandjean, A. Madhavan, L. Cech, B. O. Seguinot, R. J. Paxman, E. Smith, L. Scampavia, E. T. Powers, Christina B. Cooley, L. Plate, T. P. Spicer, J. W. Kelly, R. L. Wiseman

Chemistry Faculty Research

Activation of the IRE1/XBP1s signaling arm of the unfolded protein response (UPR) is a promising strategy to correct defects in endoplasmic reticulum (ER) proteostasis implicated in diverse diseases. However, no pharmacologic activators of this pathway identified to date are suitable for ER proteostasis remodeling through selective activation of IRE1/XBP1s signaling. Here, we use high-throughput screening to identify non-toxic compounds that induce ER proteostasis remodeling through IRE1/XBP1s activation. We employ transcriptional profiling to stringently confirm that our prioritized compounds selectively activate IRE1/XBP1s signaling without activating other cellular stress-responsive signaling pathways. Furthermore, we demonstrate that our compounds improve ER proteostasis of destabilized …

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A Novel Analytical Method For Studying Pharmacological Treatments For Affective Disorders In Neuroscience, Shane N. Berger Oct 2020

A Novel Analytical Method For Studying Pharmacological Treatments For Affective Disorders In Neuroscience, Shane N. Berger

Theses and Dissertations

Histamine and serotonin are important neurochemicals that maintain crucial brain functions. Both are thought to be altered in affective and neurodegenerative disorders such as depression and Parkinson’s disease. Histamine and serotonin are thought to modulate one another but the exact relationship remains unknown and this gap in knowledge makes diagnosing and treating disorders involving the transmitters difficult. The Hashemi lab studies serotonin neurochemistry to understand serotonin’s role in psychiatric disorders. However, histamine has remained an understudied neurotransmitter due to a lack of analytical tools. In 2015 and 2016, the Hashemi lab pioneered a novel detection method utilizing fast-scan cyclic voltammetry …

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Synthesis Of Novel Thiazole And Pyrazole Derivatives As Antimicrobial And Anticancer Agents, Md Mahbub Kabir Khan Sep 2020

Synthesis Of Novel Thiazole And Pyrazole Derivatives As Antimicrobial And Anticancer Agents, Md Mahbub Kabir Khan

Student Theses and Dissertations

This thesis contains two chapters. In chapter one, I report the synthesis of new pyrazole derivatives from dicarboxylic acid containing phenyl-derived, monotrifluoromethyl phenyl-derived, and acetovanillone-derived pyrazole aldehydes using Hantzsch ester. All of our pyrazole compounds have been synthesized efficiently using Hantzsch ester without any catalyst. Most of our pyrazole and thiazole compounds have been effectively recrystallized with acetonitrile and methanol respectively. We have synthesized 99 different pyrazole, 17 fused-thiazole ethisterone, and D-(-) norgestrel derivatives in good yield. In the present research, it has been shown possible to synthesize novel pyrazoles and thiazoles by using readily available starting materials and benign …

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Aqueous Kinetics Of Α-Hydroxyhippuric Acid Derivatives Bearing Electron-Withdrawing Groups As A Function Of Ph And Buffer Catalysts, Mohamad Imad Rafie Sep 2020

Aqueous Kinetics Of Α-Hydroxyhippuric Acid Derivatives Bearing Electron-Withdrawing Groups As A Function Of Ph And Buffer Catalysts, Mohamad Imad Rafie

Theses and Dissertations

It has been shown that carbinolamides are intermediates in the enzyme-catalyzed synthesis of -amidated peptides. Although carbinolamides are important intermediates in the production of these hormones and have roles in other biological venues, little attention has been given to their mechanisms of reaction in water, and, thus, it is difficult to speculate how their reaction would be enzymatically catalyzed. The purpose of the work presented here was to synthesize structural analogs of the biological intermediates and study their mechanism of breakdown in water. -Hydroxyhippuric acid, a substrate for the enzymatic system, provides an easily modified template for the study of …

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