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Full-Text Articles in Chemistry

Evaluation Of Chemical Immersion Treatments To Reduce Microbial Populations In Fresh Beef, Ahmed Kassem, Joseph Meade, James Gibbons, Kevina Mcgill, Ciara Walsh, James Lyng, Paul Whyte Jan 2017

Evaluation Of Chemical Immersion Treatments To Reduce Microbial Populations In Fresh Beef, Ahmed Kassem, Joseph Meade, James Gibbons, Kevina Mcgill, Ciara Walsh, James Lyng, Paul Whyte

Articles

The aim of the current study was to assess the ability of a number of chemicals (acetic Acid (AA), citric acid (CA) lactic acid (LA), sodium decanoate (SD) and trisodium phosphate (TSP)) to reduce microbial populations (total viable count, Campylobacter jejuni, Escherichia coli, Salmonella typhimurium and Listeria monocytogenes) on raw beef using an immersion system. The following concentrations of each chemical were used: 3 & 5% for AA, CA, LA, SD and 10 & 12% for TSP. Possible synergistic effects of using combinations of two chemicals sequentially (LA +CA and LA +AA) were also investigated. L*, a* and b* values …


Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis Jan 2017

Identification Of “Kratom” (Mitragyna Speciosa) Alkaloids In Commercially Available Products, Julia Grzymkowski, Michelle R. Peace, Justin Poklis

Undergraduate Research Posters

“Kratom” is the common name for the botanical mitragyna speciosa. It is a tree native to Southeast Asia in which leaves contain the psychoactive alkaloids mitragynine and 7-hydroxymitragynine. Kratom is often ingested as teas, chewed, or smoked. It acts as a stimulant in small doses and as an opioid in large doses. Overdoses can result in vomiting, seizures, and death. Recently the Drug Enforcement Agency (DEA) placed Kratom on Schedule 1, but, due to public outcry, it was almost immediately removed.

Eleven kratom based products were obtained from various tobacco shops, “headshops” and via the internet including: Choice brand …


Myofilament Calcium Sensitivity: Consequences Of The Effective Concentration Of Troponin I, Jalal K. Siddiqui, Svetlana B. Tikunova, Shane D. Walton, Bin Liu, Meredith Meyer, Pieter P. De Tombe, Nathan Neilson, Peter M. Kekenes-Huskey, Hussam E. Salhi, Paul M.L. Janssen, Brandon J. Biesiadecki, Jonathan P. Davis Dec 2016

Myofilament Calcium Sensitivity: Consequences Of The Effective Concentration Of Troponin I, Jalal K. Siddiqui, Svetlana B. Tikunova, Shane D. Walton, Bin Liu, Meredith Meyer, Pieter P. De Tombe, Nathan Neilson, Peter M. Kekenes-Huskey, Hussam E. Salhi, Paul M.L. Janssen, Brandon J. Biesiadecki, Jonathan P. Davis

Chemistry Faculty Publications

Control of calcium binding to and dissociation from cardiac troponin C (TnC) is essential to healthy cardiac muscle contraction/relaxation. There are numerous aberrant post-translational modifications and mutations within a plethora of contractile, and even non-contractile, proteins that appear to imbalance this delicate relationship. The direction and extent of the resulting change in calcium sensitivity is thought to drive the heart toward one type of disease or another. There are a number of molecular mechanisms that may be responsible for the altered calcium binding properties of TnC, potentially the most significant being the ability of the regulatory domain of TnC to …


Phthalate Plasticizers Covalently Linked To Pvc Via Copper-Free Or Copper Catalyzed Axide-Alkyne Cycloadditions, Aruna Earla, Li Longbo, Philip Costanzo, Rebecca Braslau Dec 2016

Phthalate Plasticizers Covalently Linked To Pvc Via Copper-Free Or Copper Catalyzed Axide-Alkyne Cycloadditions, Aruna Earla, Li Longbo, Philip Costanzo, Rebecca Braslau

Chemistry and Biochemistry

Plasticization of PVC was carried out by covalently linking phthalate derivatives via copper-free (thermal) or copper catalyzed azide-alkyne cycloadditions. Di(2-ethylhexyl) phthalate derivatives (DEHP-ether and DEHP-ester) were synthesized and appended to PVC at two different densities. The glass transition temperatures of the modified PVC decreased with increasing content of plasticizer. PVC-DEHP-ether gave lower glass transition temperatures than PVC-DEHP-ester, reflecting the enhanced flexibility of the ether versus ester linker.


An Examination Of Student Outcomes In Studio Chemistry, Alan L. Kiste, Gregory E. Scott, Jesse Paul Bukenberger, Miles Markmann, Jennifer Moore Dec 2016

An Examination Of Student Outcomes In Studio Chemistry, Alan L. Kiste, Gregory E. Scott, Jesse Paul Bukenberger, Miles Markmann, Jennifer Moore

Chemistry and Biochemistry

Twenty years ago, a major curriculum revision at a large, comprehensive university in the Western United States led to the implementation of an integrated lecture/laboratory (studio) experience for our engineering students taking general chemistry. Based on these twenty years of experience, construction of four purpose-built studio classrooms to house the majority of the remaining general chemistry courses was completed in 2013. A detailed study of the effects of the entire ecology of the studio experience on student success was initiated at that time. Data from content knowledge pre- and post-tests, learning attitudes surveys, and student course evaluations show positive effects …


Synthesis And Performance Of Novel Supramolecular Tools For Single-Particle Cryogenic Electron Microscopy And Drug And Gene Delivery, Kyle J. Wright Dec 2016

Synthesis And Performance Of Novel Supramolecular Tools For Single-Particle Cryogenic Electron Microscopy And Drug And Gene Delivery, Kyle J. Wright

Open Access Dissertations

High-resolution biomacromolecular structure elucidation is fundamentally important to structure-based drug design and basic research into complex biochemical processes. Cryo-EM is an emerging alternative to XRD and NMR that is complementary in many ways relative to XRD and NMR. Materials approaches to cryo-EM are anticipated to greatly facilitate the cryo-EM process, allowing progress toward a more high-throughput application of cryo-EM to address challenges in structural biology. ^ Various affinity-based approaches inspired by approaches previously introduced for 2D crystallization were developed for facilitation of cryo-EM. A library of affinity lipopolymer constructs were synthesized consisting of lipopolymers of various PEG molecular weights conjugated …


Characterization Of Wy 14,643 And Its Complex With Aldose Reductase, Michael Sawaya, Malkhey Verma, Vaishnavi Balendiran, Nigam Rath, Duilio Cascio, Ganesaratnam Balendiran Dec 2016

Characterization Of Wy 14,643 And Its Complex With Aldose Reductase, Michael Sawaya, Malkhey Verma, Vaishnavi Balendiran, Nigam Rath, Duilio Cascio, Ganesaratnam Balendiran

Chemistry & Biochemistry Faculty Works

The peroxisome proliferator, WY 14,643 exhibits a pure non-competitive inhibition pattern in the aldehyde reduction and in alcohol oxidation activities of human Aldose reductase (hAR). Fluorescence emission measurements of the equilibrium dissociation constants, Kd, of oxidized (hAR•NADP+) and reduced (hAR•NADPH) holoenzyme complexes display a 2-fold difference between them. Kd values for the dissociation of WY 14,643 from the oxidized (hAR•NADP+•WY 14,643) and reduced (hAR•NADPH•WY 14,643) ternary complexes are comparable to each other. The ternary complex structure of hAR•NADP+•WY 14,643 reveals the first structural evidence of a fibrate class drug binding to hAR. These observations demonstrate how fibrate molecules such as …


Electrogenerated Chemiluminescence Study Of Semiconductor Nanoparticles Towards Sensitive Detection Of Biomolecules, Yiliyasi Wusimanjiang Dec 2016

Electrogenerated Chemiluminescence Study Of Semiconductor Nanoparticles Towards Sensitive Detection Of Biomolecules, Yiliyasi Wusimanjiang

Dissertations

The main focus of this dissertation is to unfold the fundamental aspects of electrogenerated chemiluminescence (ECL) generation from semiconductor nanoparticles (also known as quantum dots or QDs) within different ECL systems. The ECL and photo-physical interactions between the CdTe QDs (λemission= ~760 nm) and the CdSe QDs (λemission= ~550 nm), as well as the effects of carbon nanotubes on ECL of QDs were separately investigated. Optimum experimental conditions for peptide bond formation on an electrode surface through EDC (1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride)/NHS (N-Hydroxysulfosuccinimide) coupling were also revealed using cyclic voltammetry technique. Based on the information …


A Pes Study Of Factors Influencing Metal Partitioning In Aquatic Systems: “Design Of Experiment As, Cd, Co, Cr, Cu, Pb, Ni, And Zn”, Eid A. Alkhatib, John Rapaglia, Leon Theim Dec 2016

A Pes Study Of Factors Influencing Metal Partitioning In Aquatic Systems: “Design Of Experiment As, Cd, Co, Cr, Cu, Pb, Ni, And Zn”, Eid A. Alkhatib, John Rapaglia, Leon Theim

Chemistry & Physics Faculty Publications

Mobility and bioavailability of heavy metals are related to their partitioning amongst suspended sediment and water. A Particle Entrainment Simulator (PES) is used to simulate sediment resuspention in natural surface water systems. The simulations were carried out under various conditions of water/suspended solids conditions. Five factors, each at various levels, are tested collectively: the pH of water at two levels (4 and 8), shear stress on bottom sediment at three levels (0.1, 0.3, and 0.5 N/m2 ) salinity of water at two levels (0.01 and 14.0 ppt), organic matter in sediment at three levels (0.50, 1.93, and 3.80%) and temperature …


Interactions In The Cpsrp Dependent Targeting Of Light Harvesting Chlorophyll Binding Protein To The Thylakoid Membrane, Rory Henderson Dec 2016

Interactions In The Cpsrp Dependent Targeting Of Light Harvesting Chlorophyll Binding Protein To The Thylakoid Membrane, Rory Henderson

Graduate Theses and Dissertations

Targeting of proteins is a critical component of cellular function. A universally conserved targeting system of the cytosol utilizes a signal recognition particle (SRP) to target many proteins contranslationally to the endoplasmic reticulum in eukaryotes or the inner membrane in prokaryotes. A homologous SRP system exists in the chloroplast that delivers light harvesting chlorophyll binding proteins (LHCP) to they thylakoid membrane. The chloroplast SRP (cpSRP) is a heterodimer composed of a novel 43 kDa subunit and a 54 kDa subunit homologous to a component of the SRP system, SRP54. Many details regarding the interactions between the proteins of the cpSRP …


Bioorthogonal Reactions: Synthesis And Evaluation Of Different Ligands In Copper Catalyzed Azide-Alkyne1,3-Dipolar Cycloaddition (Cuaac), Zainab Abdullah Almansaf Dec 2016

Bioorthogonal Reactions: Synthesis And Evaluation Of Different Ligands In Copper Catalyzed Azide-Alkyne1,3-Dipolar Cycloaddition (Cuaac), Zainab Abdullah Almansaf

Graduate Theses and Dissertations

The Copper CatalyzedAzide-Alkyne1,3-Dipolar Cycloaddition (CuAAC) reaction has unique features that qualify it to be one of the best click reactions. Its applications have been shown in different aspects and for multiple purposes. The oxidative degradation of biological systems (labile proteins and live cells) is, however, generally recognized as the major problem when using this reaction in living systems. Reactive oxidation species can be easily produced in the presence of copper(II), ascorbate and air, and this is the main cause of toxicity. However, the uses of ligands have shown a major impact on reducing copper toxicity, protecting Cu(I) from the redox …


Conformationally Superarmed S-Ethyl Glycosyl Donors As Effective Building Blocks For Chemoselective Oligosaccharide Synthesis In One Pot, Mithila Bandara, Jagodige Yasomanee, Nigam Rath, Christian Pedersen, Mikael Bols, Alexei Demchenko Nov 2016

Conformationally Superarmed S-Ethyl Glycosyl Donors As Effective Building Blocks For Chemoselective Oligosaccharide Synthesis In One Pot, Mithila Bandara, Jagodige Yasomanee, Nigam Rath, Christian Pedersen, Mikael Bols, Alexei Demchenko

Chemistry & Biochemistry Faculty Works

A new series of superarmed glycosyl donors has been investigated. It was demonstrated that the S-ethyl leaving group allows for high reactivity, which is much higher than that of equally equipped S-phenyl glycosyl donors that were previously investigated by our groups. The superarmed S-ethyl glycosyl donors equipped with a 2-O-benzoyl group gave complete β-stereoselectivity. Utility of the new glycosyl donors has been demonstrated in a one-pot one-addition oligosaccharide synthesis with all of the reaction components present from the beginning.


Development Of In Vivo Systems For Detecting And Studying Ribosome Inhibition By Small Molecules, Shijie Huang Nov 2016

Development Of In Vivo Systems For Detecting And Studying Ribosome Inhibition By Small Molecules, Shijie Huang

Chemistry and Chemical Biology ETDs

The ribosome is the quintessential antibacterial drug target, with many structurally and mechanistically distinct classes of antibacterial agents acting by inhibiting ribosome function. Detecting and quantifying ribosome inhibition by small molecules and investigating their binding modes and mechanisms of action are critical to antibacterial drug discovery and development efforts. To develop a ribosome inhibition assay that is operationally simple, yet provides direct information on the drug target and the mechanism of action, we have developed engineered E. coli strains harboring an orthogonal ribosome controlled green fluorescent protein reporter that produce fluorescent signal when the O-ribosome is inhibited. As a proof …


Engineering Small Molecule Based Dimerization To Induce Translation And Provide Optogenetic Control, Catherine Wright Nov 2016

Engineering Small Molecule Based Dimerization To Induce Translation And Provide Optogenetic Control, Catherine Wright

Chemistry and Chemical Biology ETDs

We wanted to develop a system that combines the spatial control of photoactivation and control of translation to build a tool to spatially control translation in neurons. This kind of tool could be used to investigate the role of spatially controlled translation of any protein in neural behavior. In this way the development and growth of neural processes could be studied to elucidate the mechanisms for spatially sensitive events such as pathfinding, repair, or long-term potentiation.

Chemically induced dimerization was used to install a switch into the activation of translation for specific genes. An abscisic acid (ABA) dependent dimerization of …


Use Of A Uav For Water Sampling To Assist Remote Sensing Of Bacterial Flora In Freshwater Environments, Dylan Cornell, Maryann Herman, Fernando Ontiveros Oct 2016

Use Of A Uav For Water Sampling To Assist Remote Sensing Of Bacterial Flora In Freshwater Environments, Dylan Cornell, Maryann Herman, Fernando Ontiveros

Undergraduate External Publications

Ground truth data collection in bodies of water traditionally relies on the use of watercraft and manual sampling. The transport and cost associated with the use of this type of equipment, as well as the time required to reach the site of collection, may all be significantly reduced by the use of small unmanned aerial vehicles (UAV) or drones. In this project we evaluate the implementation of a modified UAV with the ability to collect a small volume of surface water up to 400m offshore. The bacterial flora found in the water of several locations in the Lake Ontario-Rochester Embayment …


Infrared Spectroscopy Of The Nitrogenase Mofe Protein Under Electrochemical Control: Potential-Triggered Co Binding, P. Paengnakorn, Philip A. Ash, Sudipta K. Shaw, Karamatullah Danyal, T. Chen, Dennis R. Dean, Lance C. Seefeldt, Kylie A. Vincent Oct 2016

Infrared Spectroscopy Of The Nitrogenase Mofe Protein Under Electrochemical Control: Potential-Triggered Co Binding, P. Paengnakorn, Philip A. Ash, Sudipta K. Shaw, Karamatullah Danyal, T. Chen, Dennis R. Dean, Lance C. Seefeldt, Kylie A. Vincent

Chemistry and Biochemistry Faculty Publications

We demonstrate electrochemical control of the nitrogenase MoFe protein, in the absence of Fe protein or ATP, using europium(III/II) polyaminocarboxylate complexes as electron transfer mediators. This allows the potential dependence of proton reduction and inhibitor (CO) binding to the active site FeMo-cofactor to be established. Reduction of protons to H2 is catalyzed by the wild type MoFe protein and Β-98Tyr→His and Β-99Phe→His variants of the MoFe protein at potentials more negative than -800 mV (vs. SHE), with greater electrocatalytic proton reduction rates observed for the variants compared to the wild type protein. Electrocatalytic proton reduction is strongly …


Atomic Tiles: Manipulative Resources For Exploring Bonding And Molecular Structure, Alan L. Kiste, Rebecca G. Hooper, Gregory E. Scott, Seth Bush Oct 2016

Atomic Tiles: Manipulative Resources For Exploring Bonding And Molecular Structure, Alan L. Kiste, Rebecca G. Hooper, Gregory E. Scott, Seth Bush

Chemistry and Biochemistry

A simple manipulative resource, Atomic Tiles, is described for scaffolding the learning of Lewis structures without using algorithmic, rule-based methods of drawing. Students use Atomic Tiles to (1) create models of bonding that lead to drawing Lewis structures, (2) use the structures they create to infer patterns required for rational structures and common organic functional groups, (3) translate between Lewis structures and molecular models, and (4) use molecular models to identify isomers.


The Coastal Monitor: Vol. 1, No. 3, John Tanacredi Ph.D. Oct 2016

The Coastal Monitor: Vol. 1, No. 3, John Tanacredi Ph.D.

The Coastal Monitor

Each fall I teach a course in “Ecology” and in the spring, “Marine Biology”; two seminal courses absolutely necessary and required to complete a BS Degree in Earth and Environmental Studies at Molloy College. To a large extent I draw on my 48 years of life experiences; flight meteorologist, “Hurricane Hunter” in the US Navy (1968-1970), environmental impact analyst with the US Coast Guard’s Bridge Administration on Governors Island (1974-1978); Coastal Barrier Parks Coordinator and Research Ecologist with the National Park Service (1978-2001); Research Associate in the Invertebrate Zoology Department at the American Museum of Natural History(1982-2000); Chairman Department of …


Development Of Dihydrochalcone Functionalized Gold Nanoparticles For Augmented Antineoplastic Activity, Jason N. Payne Oct 2016

Development Of Dihydrochalcone Functionalized Gold Nanoparticles For Augmented Antineoplastic Activity, Jason N. Payne

Masters Theses & Specialist Projects

Phloridzin, an antidiabetic and antineoplastic agent usually found in fruit trees, is a dihydrochalcone constituent that has a clinical/pharmaceutical significance as a sodiumglucose linked transport 2 (SGLT2) inhibitor. Phloridzin never experienced widespread clinical usage in the pharmaceutical market due to its side effects and poor bioavailability when compared to other antidiabetic therapeutics. The poor bioavailability is primarily attributed to the degradation of the glycosidic bond of the phloridzin, resulting in the formation of phloretin, the aglycone of phloridzin and glucose. While phloretin displays a reduced capacity of SGLT2 inhibition, this nutraceutical shows enhanced antineoplastic activity in comparison to phloridzin. Gold …


Visible-Light Generation Of High-Valent Metal-Oxo Intermediates And A Biomimetic Oxidation Catalyzed By Manganese Porphyrins With Iodobenzene Diacetate, Ka Wai Kwong Oct 2016

Visible-Light Generation Of High-Valent Metal-Oxo Intermediates And A Biomimetic Oxidation Catalyzed By Manganese Porphyrins With Iodobenzene Diacetate, Ka Wai Kwong

Masters Theses & Specialist Projects

High-valent iron-oxo intermediates play central roles as active oxidants in enzymatic and synthetic catalytic oxidations. Many transition metal catalysts are designed for biomimetic studies of the predominant oxidation catalysts in Nature, the cytochrome P450 enzymes.

In this work, a new photochemical method to generate high-valent iron-oxo porphyrin models was discovered. As controlled by the electronic nature of porphyrin ligands, iron(IV)-oxo porphyrin radical cations (Compound I model) and iron(IV)-oxo porphyrin derivatives (Compound II model) were produced. These observations indicate that the photochemical reactions involve a heterolytic cleavage of O-Br in precursors to give a putative iron(V)-oxo intermediate, which might relax to …


Bioenergetics: Experimental Demonstration Of Excess Protons And Related Features, Haitham A. Saeed Oct 2016

Bioenergetics: Experimental Demonstration Of Excess Protons And Related Features, Haitham A. Saeed

Chemistry & Biochemistry Theses & Dissertations

Over the last 50 years, ever since the Nobel-prize work of Peter Mitchell’s Chemiosmotic theory, the question whether bioenergetics energy transduction occurs through localized or delocalized protons has been a controversial issue among scientists. Recently, a proton-electrostatics localization hypothesis was formulated which may provide a new and clear understanding of localized and delocalized proton-coupling energy transduction in many biological systems. The aim of this dissertation was to test this new hypothesis.

To demonstrate the fundamental behavior of localized protons in a pure water-membrane-water system in relation to the newly derived pmf equation, excess protons and excess hydroxyl anions were generated …


Specific Binding Affinity Of The Non-Catalytic Domain Of Eukaryotic Like Type Ib Topoisomerase Of Vaccinia Virus, Benjamin R. Reed Sep 2016

Specific Binding Affinity Of The Non-Catalytic Domain Of Eukaryotic Like Type Ib Topoisomerase Of Vaccinia Virus, Benjamin R. Reed

Dissertations, Theses, and Capstone Projects

Topoisomerases are ubiquitous proteins that alter supercoiling in double stranded DNA (dsDNA) during transcription and replication and. vaccinia and the closely related poxvirus variola virus, at 314 amino acids in length, encode the smallest of the type I topoisomerases(TopIB). TopIB is a two domain protein that recognizes the sequence 5’-T/CCCTT, cleaves at the 3’-end and relaxes supercoiling through rotation. The C-terminal domain (CTD) alone contains the catalytic activity and specificity. Deletion of the N-terminal domain results in a greatly reduced rate of relaxation and rapid dissociation. Biochemical data suggests that the N-terminal domain (NTD) is important for pre-cleavage binding and …


Metabolic Profiling Of Genetically Modified Potato Periderm Tissues, Liqing Jin Sep 2016

Metabolic Profiling Of Genetically Modified Potato Periderm Tissues, Liqing Jin

Dissertations, Theses, and Capstone Projects

Potato tubers are protected from dehydration and pathogens by a covering peel (periderm) impregnated with suberin, a complex cross-linked biopolymer that contains both polyaliphatic and lignin-like aromatic domains. Current models describing the macromolecular structure of suberin assume that ferulic acid cross-links both domains as it may form carboxyl ester bonds with aliphatic monomers and non-ester radical-coupled bonds with phenolics. Ferulic acid also links by ester bonds to glycans and acts in cross-linking polysaccharides and lignin. Fatty alcohol/ω-hydroxyacid hydroxycinnamoyl transferase (FHT) is a BADH acyltransferase responsible for the synthesis of akyl-ferulates that is necessary for suberin biosynthesis. Periderm from FHT-RNAi …


Metabolic Profiling And Polymer Formation Of Gene Silenced Potato Periderms, Qing Cai Sep 2016

Metabolic Profiling And Polymer Formation Of Gene Silenced Potato Periderms, Qing Cai

Dissertations, Theses, and Capstone Projects

Suberin is a biopolyester constituent of specialized plant periderm tissues formed within the phellem cell walls. Suberin and waxes of the periderm layer act to prevent water diffusion, mechanical breakdown and pathogenic invasion in plants. Ferulic esters, ω-hydroxyacids and α,ω-fatty diacids are considered to be the most important linkage between aliphatic and aromatic suberin domains and also linked with cell-wall polysaccharides. The potato gene FHT (fatty ω- hydroxyacid/fatty alcohol hydroxycinnamoyl transferase) esterifies ferulic acid to suberin. Diminished levels of feruloyl transferase activity have been associated with lowered amounts of feruloyl esters of fatty acids in both suberin-associated waxes and suberin …


Emissions Of Nitrogen-Containing Organic Compounds From The Burning Of Herbaceous And Arboraceous Biomass: Fuel Composition Dependence And The Variability Of Commonly Used Nitrile Tracers, Matthew M. Coggon, Patrick R. Veres, Bin Yuan, Abigail Koss, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Jeff Peischl, Kenneth C. Aikin, Chelsea E. Stockwell, Lindsay E. Hatch, Thomas B. Ryerson, James M. Roberts, Robert J. Yokelson, Joost A. De Gouw Sep 2016

Emissions Of Nitrogen-Containing Organic Compounds From The Burning Of Herbaceous And Arboraceous Biomass: Fuel Composition Dependence And The Variability Of Commonly Used Nitrile Tracers, Matthew M. Coggon, Patrick R. Veres, Bin Yuan, Abigail Koss, Carsten Warneke, Jessica B. Gilman, Brian M. Lerner, Jeff Peischl, Kenneth C. Aikin, Chelsea E. Stockwell, Lindsay E. Hatch, Thomas B. Ryerson, James M. Roberts, Robert J. Yokelson, Joost A. De Gouw

Chemistry and Biochemistry Faculty Publications

Volatile organic compounds (VOCs) emitted from residential wood and crop residue burning were measured in Colorado, U.S. When compared to the emissions from crop burning, residential wood burning exhibited markedly lower concentrations of acetonitrile, a commonly used biomass burning tracer. For both herbaceous and arboraceous fuels, the emissions of nitrogen-containing VOCs (NVOCs) strongly depend on the fuel nitrogen content; therefore, low NVOC emissions from residential wood burning result from the combustion of low-nitrogen fuel. Consequently, the emissions of compounds hazardous to human health, such as HNCO and HCN, and the formation of secondary pollutants, such as ozone generated by NOx, …


Field Measurements Of Trace Gases And Aerosols Emitted By Peat Fires In Central Kalimantan, Indonesia, During The 2015 El Niño, Chelsea E. Stockwell, Thilina Jayarathne, Mark A. Cochrane, Kevin C. Ryan, Erianto I. Putra, Bambang H. Saharjo, Ati D. Nurhayati, Israr Albar, Donald R. Blake, Isobel J. Simpson, Elizabeth A. Stone, Robert J. Yokelson Sep 2016

Field Measurements Of Trace Gases And Aerosols Emitted By Peat Fires In Central Kalimantan, Indonesia, During The 2015 El Niño, Chelsea E. Stockwell, Thilina Jayarathne, Mark A. Cochrane, Kevin C. Ryan, Erianto I. Putra, Bambang H. Saharjo, Ati D. Nurhayati, Israr Albar, Donald R. Blake, Isobel J. Simpson, Elizabeth A. Stone, Robert J. Yokelson

Chemistry and Biochemistry Faculty Publications

Peat fires in Southeast Asia have become a major annual source of trace gases and particles to the regional-global atmosphere. The assessment of their influence on atmospheric chemistry, climate, air quality, and health has been uncertain partly due to a lack of field measurements of the smoke characteristics. During the strong 2015 El Niño event we deployed a mobile smoke sampling team in the Indonesian province of Central Kalimantan on the island of Borneo and made the first, or rare, field measurements of trace gases, aerosol optical properties, and aerosol mass emissions for authentic peat fires burning at various depths …


Nepal Ambient Monitoring And Source Testing Experiment (Namaste): Emissions Of Trace Gases And Light-Absorbing Carbon From Wood And Dung Cooking Fires, Garbage And Crop Residue Burning, Brick Kilns, And Other Sources, Chelsea E. Stockwell, Ted J. Christian, J. Douglas Goetz, Thilina Jayarathne, Prakash V. Bhave, Puppala S. Praveen, Sagar Adhikari, Rashmi Maharjan, Peter F. Decarlo, Elizabeth A. Stone, Eri Saikawa, Donald R. Blake, Isobel J. Simpson, Robert J. Yokelson, Arnico K. Panday Sep 2016

Nepal Ambient Monitoring And Source Testing Experiment (Namaste): Emissions Of Trace Gases And Light-Absorbing Carbon From Wood And Dung Cooking Fires, Garbage And Crop Residue Burning, Brick Kilns, And Other Sources, Chelsea E. Stockwell, Ted J. Christian, J. Douglas Goetz, Thilina Jayarathne, Prakash V. Bhave, Puppala S. Praveen, Sagar Adhikari, Rashmi Maharjan, Peter F. Decarlo, Elizabeth A. Stone, Eri Saikawa, Donald R. Blake, Isobel J. Simpson, Robert J. Yokelson, Arnico K. Panday

Chemistry and Biochemistry Faculty Publications

The Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE) campaign took place in and around the Kathmandu Valley and in the Indo-Gangetic Plain (IGP) of southern Nepal during April 2015. The source characterization phase targeted numerous important but undersampled (and often inefficient) combustion sources that are widespread in the developing world such as cooking with a variety of stoves and solid fuels, brick kilns, open burning of municipal solid waste (a.k.a. trash or garbage burning), crop residue burning, generators, irrigation pumps, and motorcycles. NAMaSTE produced the first, or rare, measurements of aerosol optical properties, aerosol mass, and detailed trace gas …


Hemi-Methylated Dna Regulates Dna Methylation Inheritance Through Allosteric Activation Of H3 Ubiquitylation By Uhrf1, Joseph S. Harrison, Evan M. Cornett, Dennis Goldfarb, Paul A. Darosa, Zimeng M. Li, Feng Yan, Bradley M. Dickson, Angela H. Guo, Daniel V. Cantu, Lilia Kaustov, Peter J. Brown, Cheryl H. Arrowsmith, Dorothy A. Erie, Michael B. Major, Rachel E. Klevit, Krzysztof Krajewski, Brian Kuhlman, Brian D. Strahl, Scott B. Rothbart Sep 2016

Hemi-Methylated Dna Regulates Dna Methylation Inheritance Through Allosteric Activation Of H3 Ubiquitylation By Uhrf1, Joseph S. Harrison, Evan M. Cornett, Dennis Goldfarb, Paul A. Darosa, Zimeng M. Li, Feng Yan, Bradley M. Dickson, Angela H. Guo, Daniel V. Cantu, Lilia Kaustov, Peter J. Brown, Cheryl H. Arrowsmith, Dorothy A. Erie, Michael B. Major, Rachel E. Klevit, Krzysztof Krajewski, Brian Kuhlman, Brian D. Strahl, Scott B. Rothbart

College of the Pacific Faculty Articles

The epigenetic inheritance of DNA methylation requires UHRF1, a histone- and DNA-binding RING E3 ubiquitin ligase that recruits DNMT1 to sites of newly replicated DNA through ubiquitylation of histone H3. UHRF1 binds DNA with selectivity towards hemi-methylated CpGs (HeDNA); however, the contribution of HeDNA sensing to UHRF1 function remains elusive. Here, we reveal that the interaction of UHRF1 with HeDNA is required for DNA methylation but is dispensable for chromatin interaction, which is governed by reciprocal positive cooperativity between the UHRF1 histone- and DNA-binding domains. HeDNA recognition activates UHRF1 ubiquitylation towards multiple lysines on the H3 tail adjacent to the …


Gc Verification Of The Spacecraft Atmosphere Monitor, Jessica S. Castro, Richard D. Kidd, Jeffrey D. Hein Sep 2016

Gc Verification Of The Spacecraft Atmosphere Monitor, Jessica S. Castro, Richard D. Kidd, Jeffrey D. Hein

STAR Program Research Presentations

International Space Station crew members face the unique challenge of maintaining air quality due to the volatile organic compounds (VOCs) that have the potential to accumulate at unsafe levels. The Spacecraft Atmosphere Monitor (SAM) is a miniature gas chromatograph/mass spectrometer (GCMS) designed to measure major constituents (such as N2, O2 and CO2) and trace VOCs within the cabin of the spacecraft. The gas chromatograph is responsible for separating the sample into its components in order to be characterized. The oven of the gas chromatograph must reach a temperature of 150°C in order to heat constituents …


A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph Meisel, George Gokel Sep 2016

A Simplified Direct Lipid Mixing Lipoplex Preparation: Comparison Of Liposomal-, Dimethylsulfoxide-, And Ethanol-Based Methods, Joseph Meisel, George Gokel

Chemistry & Biochemistry Faculty Works

Established transfection methodology often uses commercial reagents, which must be formed into liposomes in a sequence of about half a dozen steps. The simplified method reported here is a direct lipid mixing approach that requires fewer steps, less manipulation, and is less time-consuming. Results are comparable to those obtained with more commonly used methods, as judged by a variety of analytical techniques and by comparisons of transfection results. The method reported here may be applied to non-liposome-forming compounds, thereby greatly expanding the range of structures that can be tested for transfection ability.