Synthesis And Anti-Proliferative Activity Of N,N’-Bis(Arylmethyl)Benzimidazolium Salts,
2015
University of Akron Main Campus
Synthesis And Anti-Proliferative Activity Of N,N’-Bis(Arylmethyl)Benzimidazolium Salts, Travis M. Williams
Williams Honors College, Honors Research Projects
A series of N,N’-bis(arylmethyl)benzimidazolium salts with hydrophilic and lipophilic substituents have been synthesized, characterized, and tested against select non-small cell cancer cell lines. Substituent variations on the imidazole ring have shown that lipophilicity and hydrophilicity can influence the imidazolium salts’ anti-proliferative activity and aqueous solubility.
Exploiting Enzymatic Dynamic Reductive Kinetic Resolution
(Dyrkr) In Stereocontrolled Synthesis,
2015
University of Nebraska–Lincoln
Exploiting Enzymatic Dynamic Reductive Kinetic Resolution (Dyrkr) In Stereocontrolled Synthesis, Gregory A. Applegate, David B. Berkowitz
David Berkowitz Publications
Over the past two decades, the domains of both frontline synthetic organic chemistry and process chemistry have seen an increase in crosstalk between asymmetric organic/organometallic approaches and enzymatic approaches to stereocontrolled synthesis. This review highlights the particularly auspicious role for dehydrogenase enzymes in this endeavor, with a focus on dynamic reductive kinetic resolutions (DYRKR) to “deracemize” building blocks, often setting two stereocenters in so doing. The scope and limitations of such dehydrogenase-mediated processes are overviewed, as are future possibilities for the evolution of enzymatic DYRKR.
Research-Based Implementation Of Peer Instruction:
A Literature Review,
2015
University of Nebraska-Lincoln
Research-Based Implementation Of Peer Instruction: A Literature Review, Trisha Vickrey, Kaitlyn Rosploch, Reihaneh Rahmanian, Matthew Pilarz, Marilyne Stains
Department of Chemistry: Faculty Publications
Current instructional reforms in undergraduate science, technology, engineering, and mathematics (STEM) courses have focused on enhancing adoption of evidence-based instructional practices among STEM faculty members. These practices have been empirically demonstrated to enhance student learning and attitudes. However, research indicates that instructors often adapt rather than adopt practices, unknowingly compromising their effectiveness. Thus, there is a need to raise awareness of the research-based implementation of these practices, develop fidelity of implementation protocols to understand adaptations being made, and ultimately characterize the true impact of reform efforts based on these practices. Peer instruction (PI) is an example of an evidence-based instructional …
New Insight Into The Helium-Induced Damage In Max Phase Ti3Alc2
By First-Principles Studies,
2015
Division of Functional Materials and Nanodevices, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang
New Insight Into The Helium-Induced Damage In Max Phase Ti3Alc2 By First-Principles Studies, Yiguo Xu, Xiaojing Bai, Xianhu Zha, Qing Huang, Jian He, Kan Luo, Yuhong Zhou, Timothy C. Germann, Joseph S. Francisco, Shiyu Du
Department of Chemistry: Faculty Publications
In the present work, the behavior of He in the MAX phase Ti3AlC2 material is investigated using first-principle methods. It is found that, according to the predicted formation energies, a single He atom favors residing near the Al plane in Ti3AlC2. The results also show that Al vacancies are better able to trap He atoms than either Ti or C vacancies. The formation energies for the secondary vacancy defects near an Al vacancy or a C vacancy are strongly influenced by He impurity content. According to the present results, the existence of trapped He atoms in primary Al vacancy can …
Communication: Spectroscopic Consequences Of Proton Delocalization
In Ochco+,
2015
Georgia Southern University
Communication: Spectroscopic Consequences Of Proton Delocalization In Ochco+, Ryan C. Fortenberry, Qi Yu, John S. Mancini, Joel M. Bowman, Timothy J. Lee, T. Daniel Crawford, William F. Klemperer, Joseph S. Francisco
Department of Chemistry: Faculty Publications
Even though quartic force fields (QFFs) and highly accurate coupled cluster computations describe the OCHCO+ cation at equilibrium as a complex between carbon monoxide and the formyl cation, two notable and typical interstellar and atmospheric molecules, the prediction from the present study is that the equilibrium C∞v structure is less relevant to observables than the saddle-point D∞h structure. This is the conclusion from diffusion Monte Carlo and vibrational self-consistent field/virtual state configuration interaction calculations utilizing a semi-global potential energy surface. These calculations demonstrate that the proton “rattle” motion (ν6) has centrosymmetric delocalization of the …
Structural And Optical Properties Of Cobalt Slanted Nanopillars Conformally
Coated With Few-Layer Graphene,
2015
University of Nebraska—Lincoln
Structural And Optical Properties Of Cobalt Slanted Nanopillars Conformally Coated With Few-Layer Graphene, Peter M. Wilson, Alexey Lipatov, Daniel Schmidt, Eva Schubert, Mathias Schubert, Alexander Sinitskii, Tino Hofmann
Department of Chemistry: Faculty Publications
Optical characterization of anisotropic multicomponent nanostructures is generally not a trivial task, since the relation between a material’s structural properties and its permittivity tensor is nonlinear. In this regard, an array of slanted cobalt nanopillars that are conformally coated with few-layer graphene is a particularly challenging object for optical characterization, as it has a complex anisotropic geometry and comprises several materials with different topologies and filling fractions. Normally, a detailed characterization of such complex nanostructures would require a combination of several microscopic and spectroscopic techniques. In this letter, we demonstrate that the important structural parameters of these graphene-coated sculptured thin …
Few-Layer Titanium Trisulfide (Tis3) Field-Effect
Transistors,
2015
University of Nebraska-Lincoln
Few-Layer Titanium Trisulfide (Tis3) Field-Effect Transistors, Alexey Lipatov, Peter M. Wilson, Mikhail Shekhirev, Jacob D. Teeter, Ross Netusil, Alexander Sinitskii
Department of Chemistry: Faculty Publications
Titanium trisulfide (TiS3) is a promising layered semiconductor material. Several-mm-long TiS3 whiskers can be conveniently grown by the direct reaction of titanium and sulfur. In this study, we exfoliated these whiskers using the adhesive tape approach and fabricated few-layer TiS3 field-effect transistors (FETs). The TiS3 FETs showed an n-type electronic transport with roomtemperature field-effect mobilities of 18-24 cm2V-1s-1 and ON/OFF ratios up to 300. We demonstrate that TiS3 is compatible with the conventional atomic layer deposition (ALD) procedure for Al2O3. ALD of alumina on TiS3 …
Biotechnological Production
Of 1,2,4-Butanetriol: An Efficient
Process To Synthesize Energetic
Material Precursor From Renewable
Biomass,
2015
Chinese Academy of Sciences
Biotechnological Production Of 1,2,4-Butanetriol: An Efficient Process To Synthesize Energetic Material Precursor From Renewable Biomass, Yujin Cao, Wei Niu, Jiantao Guo, Mo Xian, Huizhou Liu
Department of Chemistry: Faculty Publications
1,2,4-Butanetriol (BT) is a valuable chemical with extensive applications in many different fields. The traditional chemical routes to synthesize BT suffer from many drawbacks, e.g., harsh reaction conditions, multiple steps and poor selectivity, limiting its industrial production. In this study, an engineered Escherichia coli strain was constructed to produce BT from xylose, which is a major component of the lignocellulosic biomass. Through the coexpression of a xylose dehydrogenase (CCxylB) and a xylonolactonase (xylC) from Caulobacter crescentus, native E. coli xylonate dehydratase (yjhG), a 2-keto acid decarboxylase from Pseudomonas putida (mdlC) and …
Fine-Tuning Interaction Between Aminoacyl-Trna Synthetase And Trna For Efficient Synthesis Of Proteins Containing Unnatural Amino Acids,
2015
University of Nebraska-Lincoln
Fine-Tuning Interaction Between Aminoacyl-Trna Synthetase And Trna For Efficient Synthesis Of Proteins Containing Unnatural Amino Acids, Nanxi Wang, Tong Ju, Wei Niu, Jiantao Guo
Department of Chemistry: Faculty Publications
By using a directed evolution approach, we have identified aminoacyl-tRNA synthetase variants with significantly enhanced activity for the incorporation of unnatural amino acids into proteins in response to the amber nonsense codon in bacteria. We demonstrated that the optimization of anticodon recognition of tRNA by aminoacyltRNA synthetase led to improved incorporation efficiency that is unnatural amino acid-specific. The findings will facilitate the creation of an optimized system for the genetic incorporation of unnatural amino acids in bacteria.
A Comparison Of Energy-Resolved Vibrational
Activation/Dissociation Characteristics Of Protonated
And Sodiated High Mannose N-Glycopeptides,
2015
University of Nebraska-Lincoln
A Comparison Of Energy-Resolved Vibrational Activation/Dissociation Characteristics Of Protonated And Sodiated High Mannose N-Glycopeptides, Forouzan Aboufazeli, Venkata Kolli, Eric D. Dodds
Department of Chemistry: Faculty Publications
Fragmentation of glycopeptides in tandem mass spectrometry (MS/MS) plays a pivotal role in site-specific protein glycosylation profiling by allowing specific oligosaccharide compositions and connectivities to be associated with specific loci on the corresponding protein. Although MS/MS analysis of glycopeptides has been successfully performed using a number of distinction dissociation methods, relatively little is known regarding the fragmentation characteristics of glycopeptide ions with various charge carriers. In this study, energy-resolved vibrational activation/ dissociation was examined via collision-induced dissociation for a group of related high mannose tryptic glycopeptides as their doubly protonated, doubly sodiated, and hybrid protonated sodium adduct ions. The doubly …
Stretchable Conductive
Composites For Use In Soft Devices,
2015
Cambridge, MA
Stretchable Conductive Composites For Use In Soft Devices, Joshua Aaron Lessing, Stephen A. Morin, George M. Whitesides
Department of Chemistry: Faculty Publications
An elastically-deformable, conductive composite using elastomers and conductive fibers and simple fabrication procedures is provided. Conductive elastomeric composites offer low resistance to electrical current and are elastic over large (>25%) extensional strains. They can be easily interfaced/built into structures fabricated from elastomeric polymers.
Apparatus, Systems, And Methods
For Modular Soft Robots,
2015
University of Nebraska - Lincoln
Apparatus, Systems, And Methods For Modular Soft Robots, Stephen A. Morin, Sen Wai Kwok, Robert F. Shepherd, George M. Whitesides
Department of Chemistry: Faculty Publications
Apparatus, Systems, and methods for providing modular soft robots are disclosed. In particular, the disclosed modular soft robot can include a flexible actuator having a plurality of molded flexible units. Each molded flexible unit can include a mechanical connector configured to provide a physical coupling to another molded flexible unit, and the plurality of molded flexible units are arranged to form an embedded fluidic channel. The modular soft robot can also include an inlet coupled to the embedded fluidic channel, where the inlet is configured to receive pressurized or depressurized fluid to inflate or deflate a portion of the flexible …
Recyclable Magnetite Nanoparticle Catalyst For One-Pot
Conversion Of Cellobiose To 5-Hydroxymethylfurfural In Water,
2015
University of Nebraska - Lincoln
Recyclable Magnetite Nanoparticle Catalyst For One-Pot Conversion Of Cellobiose To 5-Hydroxymethylfurfural In Water, Anuja Bhalkikar, Zane C. Gernhart, Chin Li Cheung
Department of Chemistry: Faculty Publications
Environmentally benign and easily recoverable magnetite nanoparticles (Fe3O4 NPs) were demonstrated to catalyze the one-pot conversion of cellobiose, a glucose disaccharide, to 5-hydroxymethylfurfural (5-HMF).Theconversion was achieved in water under hydrothermal conditions.The catalytic activity of Fe3O4 NPs surpassed those of iron (II) and iron (III) chlorides in this reaction. Optimized cellobiose conversion reactions catalyzed with Fe3O4 NPs gave the highest 5-HMF yields of 23.4 ± 0.6% at 160∘C for 24 hours. After three reuses, the Fe3O4 NP catalyst retained its catalytic activity with similar 5-HMF yields, demonstrating …
Simulation Evidence Of Hexagonal-To-Tetragonal Znse Structure Transition: A Monolayer Material With A Wide-Range Tunable Direct Bandgap,
2015
University of Nebraska-Lincoln
Simulation Evidence Of Hexagonal-To-Tetragonal Znse Structure Transition: A Monolayer Material With A Wide-Range Tunable Direct Bandgap, Lei Li, Pengfei Li, Ning Lu, Jun Dai, Xiao Cheng Zeng
Department of Chemistry: Faculty Publications
2D material with tunable direct bandgap in the intermediate region (i.e., ≈2–3 eV) is key to the achievement of high efficiency in visible-light optical devices. Herein, a simulation evidence of structure transition of monolayer ZnSe from the experimental pseudohexagonal structure to the tetragonal structure (t-ZnSe) under lateral pressure is shown, suggesting a possible fabrication route to achieve the t-ZnSe monolayer. The as-produced t-ZnSe monolayer exhibits highly tunable bandgap under the biaxial strains, allowing strain engineering of t-ZnSe’s bandgap over a wide range of 2–3 eV. Importantly, even under the biaxial strain up to 7%, the t-ZnSe monolayer still keeps its …
Affinity Chromatography: A Historical Perspective,
2015
University of Nebraska-Lincoln
Affinity Chromatography: A Historical Perspective, David S. Hage, Ryan E. Matsuda
David Hage Publications
Affinity chromatography is one of the most selective and versatile forms of liquid chromatography for the separation or analysis of chemicals in complex mixtures. This method makes use of a biologically related agent as the stationary phase, which provides an affinity column with the ability to bind selectively and reversibly to a given target in a sample. This review examines the early work in this method and various developments that have lead to the current status of this technique. The general principles of affinity chromatography are briefly described as part of this discussion. Past and recent efforts in the generation …
Chromatographic Immunoassays: Strategies And Recent Developments In The Analysis Of Drugs And Biological Agents,
2015
University of Nebraska-Lincoln
Chromatographic Immunoassays: Strategies And Recent Developments In The Analysis Of Drugs And Biological Agents, Ryan E. Matsuda, Elliott Rodriguez, Doddavenkatanna Suresh, David S. Hage
David Hage Publications
A chromatographic immunoassay is a technique in which an antibody or antibodyrelated agent is used as part of a chromatographic system for the isolation or measurement of a specific target. Various binding agents, detection methods, supports and assay formats have been developed for this group of methods, and applications have been reported that range from drugs, hormones and herbicides to peptides, proteins and bacteria. This review discusses the general principles and applications of chromatographic immunoassays, with an emphasis being given to methods and formats that have been developed for the analysis of drugs and biological agents. The relative advantages or …
Predicting Aqueous Solubility Of Pharmaceutical Agents By Solid Dispersion Prepared By Solvent Evaporation Method,
2015
University of the Pacific
Predicting Aqueous Solubility Of Pharmaceutical Agents By Solid Dispersion Prepared By Solvent Evaporation Method, Karthik Reddy Patlolla
University of the Pacific Theses and Dissertations
Solubility of active pharmaceutical agents is a crucial process that determines drug absorption and ultimately its bioavailability. Many of the new therapeutically beneficial compounds discovered are lipophilic requiring various solubility enhancement strategies to improve their solubility. Among these strategies, solubility enhancement using solid dispersions is a leading method. To obtain a desirable increase in the solubility of a poorly-soluble compound, a good understanding of the molecular descriptors influencing the enhancement of solubility is essential. Therefore, the major research objective was to determine the descriptors which significantly influence the solubility enhancement by solid dispersions. After enhancing the solubility of selected poorly-soluble …
Physicochemical And Structural Analysis Of Polymers As Putative Drugs,
2015
VCU
Physicochemical And Structural Analysis Of Polymers As Putative Drugs, Meghan L. Thompson
Theses and Dissertations
Sulfated low molecular weight lignins (LMWLs) have shown good activity as anticoagulants by allosterically inhibiting thrombin, as well as promising agents for treating emphysema through inhibition of elastolysis, oxidation, and inflammation. Sulfated LMWLs are chemo-enzymatically synthesized from starting monomers caffeic, ferulic, and sinapic acid into sulfated dehydropolymers known as CDS, FDS, and SDS. To further the LMWLs’ development as drugs, their structural composition and physicochemical characteristics were defined in this work. The molecular weight distribution profile of the sulfated LMWLs from size exclusion chromatography performed on a high pressure liquid chromatography system (SEC-HPLC) changed from bimodal when no surfactant is …
Colloidal And Biological Properties Of Triscationic Amphiphiles With One Or Two Tails,
2014
James Madison University
Colloidal And Biological Properties Of Triscationic Amphiphiles With One Or Two Tails, John N. Marafino
Masters Theses, 2010-2019
The decline in the development of novel antimicrobials, combined with the misusage and over prescription of antibiotics, has contributed to the increasing prevalence of antimicrobial-resistant infections. Thus development of effective novel disinfectants could reduce the transmission of pathogens and decrease the risk of infection by antibiotic resistant organisms. The antimicrobial activity of amphiphiles, compounds with hydrophobic and hydrophilic regions, was first reported in 1935, and has influenced the synthesis of amphiphiles with variations in structure. In this study, three series of amphiphiles were synthesized by two subsequent Menshutkin reactions. Each amphiphile contains one or two hydrocarbon tails ranging from 8 …
New 4-Aminoquinoline Compounds To Reverse Drug Resistance In P. Falciparum Malaria, And A Survey Of Early European Antimalarial Treatments,
2014
Portland State University
New 4-Aminoquinoline Compounds To Reverse Drug Resistance In P. Falciparum Malaria, And A Survey Of Early European Antimalarial Treatments, Katherine May Liebman
Dissertations and Theses
Intermittent fevers caused by Plasmodium parasites have been known for millennia, and have caused untold human suffering. Today, millions of people are afflicted by malaria each year, and hundreds of thousands die. Historically, the most successful synthetic antimalarial drug was chloroquine, as it was safe, inexpensive, and highly efficacious. However, plasmodial resistance to chloroquine now greatly limits its utility. Previously in our laboratories it has been shown that attachment of a "reversal agent moiety" to the side chain of chloroquine can result in the restoration of activity against chloroquine-resistant strains of P. falciparum malaria. In the first part of the …
