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Trace Gas And Particle Emissions From Domestic And Industrial Biofuel Use And Garbage Burning In Central Mexico, Ted J. Christian, Robert Yokelson, B. Cardenas, L. T. Molina, G. Engling, S. C. Hsu 2010 University of Montana - Missoula

Trace Gas And Particle Emissions From Domestic And Industrial Biofuel Use And Garbage Burning In Central Mexico, Ted J. Christian, Robert Yokelson, B. Cardenas, L. T. Molina, G. Engling, S. C. Hsu

Chemistry and Biochemistry Faculty Publications

In central Mexico during the spring of 2007 we measured the initial emissions of 12 gases and the aerosol speciation for elemental and organic carbon (EC, OC), anhydrosugars, Cl(-), NO(3)(-), and 20 metals from 10 cooking fires, four garbage fires, three brick making kilns, three charcoal making kilns, and two crop residue fires. Global biofuel use has been estimated at over 2600 Tg/y. With several simple case studies we show that cooking fires can be a major, or the major, source of several gases and fine particles in developing countries. Insulated cook stoves with chimneys were earlier shown ...


Evolution Of Trace Gases And Particles Emitted By A Chaparral Fire In California, S. K. Akagi, J. S. Craven, J. W. Taylor, G. R. McMeeking, Robert J. Yokelson, I. R. Burling, S. P. Urbanski, C. E. Wold, J. H. Seinfeld, H. Coe, M. J. Alvarado, D. R. Weise 2010 University of Montana - Missoula

Evolution Of Trace Gases And Particles Emitted By A Chaparral Fire In California, S. K. Akagi, J. S. Craven, J. W. Taylor, G. R. Mcmeeking, Robert J. Yokelson, I. R. Burling, S. P. Urbanski, C. E. Wold, J. H. Seinfeld, H. Coe, M. J. Alvarado, D. R. Weise

Chemistry and Biochemistry Faculty Publications

Biomass burning (BB) is a major global source of trace gases and particles. Accurately representing the production and evolution of these emissions is an important goal for atmospheric chemical transport models. We measured a suite of gases and aerosols emitted from an 81 hectare prescribed fire in chaparral fuels on the central coast of California, US on 17 November 2009. We also measured physical and chemical changes that occurred in the isolated down-wind plume in the first similar to 4 h after emission. The measurements were carried out onboard a Twin Otter aircraft outfitted with an airborne Fourier transform infrared ...


Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, GM Burkart, RC Augustine, E Kerdavid, E Tuzel, M Bezanilla 2010 University of Massachusetts - Amherst

Myosin Xi Is Essential For Tip Growth In Physcomitrella Patens, L Vidali, Gm Burkart, Rc Augustine, E Kerdavid, E Tuzel, M Bezanilla

Magdalena Bezanilla

Class XI myosins are plant specific and responsible for cytoplasmic streaming. Because of the large number of myosin XI genes in angiosperms, it has been difficult to determine their precise role, particularly with respect to tip growth. The moss Physcomitrella patens provides an ideal system to study myosin XI function. P. patens has only two myosin XI genes, and these genes encode proteins that are 94% identical to each other. To determine their role in tip growth, we used RNA interference to specifically silence each myosin XI gene using 5′ untranslated region sequences. We discovered that the two myosin XI ...


Methionine-R-Sulfoxide Reductases And Biological Importance Of Free Methionine Sulfoxide Reduction, Byung Cheon Lee 2010 University of Nebraska - Lincoln

Methionine-R-Sulfoxide Reductases And Biological Importance Of Free Methionine Sulfoxide Reduction, Byung Cheon Lee

Theses and Dissertations in Biochemistry

We identified and functionally characterized yeast fRMsr homolog which showed specificity for reduction of free Met-R-SO and contributed to oxidative stress resistance of yeast cells. We further identified three conserved Cys which participate in catalysis through disulfide exchange. Evolutionary analyses revealed that the occurrence of fRMSr is restricted to unicellular organisms. We further found that mammalian MsrA can reduce free Met-S-SO, whereas MsrBs do not reduce free Met-R-SO. Consistent with these findings and the lack of fRMsr, mammalian cells could not grow in media that replaced Met with Met-R-SO. However, they grew in the presence of free Met-S-SO, which was ...


Electrochemical Sensing In Paper-Based Microfluidic Devices, Zhihong Nie, Christian A. Nijhuis, Jinlong Gong, Xin Chen, Alexander Kumachev, Andres W. Martinez, Max Narovlyansky, George M. Whitesides 2010 Harvard University

Electrochemical Sensing In Paper-Based Microfluidic Devices, Zhihong Nie, Christian A. Nijhuis, Jinlong Gong, Xin Chen, Alexander Kumachev, Andres W. Martinez, Max Narovlyansky, George M. Whitesides

Chemistry and Biochemistry

This paper describes the fabrication and the performance of microfluidic paper-based electrochemical sensing devices (we call the microfluidic paper-based electrochemical devices, μPEDs). The μPEDs comprise paper-based microfluidic channels patterned by photolithography or wax printing, and electrodes screen-printed from conducting inks (e.g., carbon or Ag/AgCl). We demonstrated that the μPEDs are capable of quantifying the concentrations of various analytes (e.g., heavy-metal ions and glucose) in aqueous solutions. This low-cost analytical device should be useful for applications in public health, environmental monitoring, and the developing world.


Programmable Diagnostic Devices Made From Paper And Tape, Andres W. Martinez, Scott T. Phillips, Zhihong Nie, Chao-Min Cheng, Emanuel Carrilho, Benjamin J. Wiley, George M. Whitesides 2010 Harvard University

Programmable Diagnostic Devices Made From Paper And Tape, Andres W. Martinez, Scott T. Phillips, Zhihong Nie, Chao-Min Cheng, Emanuel Carrilho, Benjamin J. Wiley, George M. Whitesides

Chemistry and Biochemistry

This paper describes three-dimensional microfluidic paper-based analytical devices (3-D μPADs) that can be programmed (postfabrication) by the user to generate multiple patterns of flow through them. These devices are programmed by pressing single-use ‘on’ buttons, using a stylus or a ballpoint pen. Pressing a button closes a small space (gap) between two vertically aligned microfluidic channels, and allows fluids to wick from one channel to the other. These devices are simple to fabricate, and are made entirely out of paper and double-sided adhesive tape. Programmable devices expand the capabilities of μPADs and provide a simple method for controlling the movement ...


Millimeter-Scale Contact Printing Of Aqueous Solutions Using A Stamp Made Out Of Paper And Tape, Chao-Min Cheng, Aaron D. Mazzeo, Jinlong Gong, Andres W. Martinez, Scott T. Phillips, Nina Jain, George M. Whitesides 2010 Harvard University

Millimeter-Scale Contact Printing Of Aqueous Solutions Using A Stamp Made Out Of Paper And Tape, Chao-Min Cheng, Aaron D. Mazzeo, Jinlong Gong, Andres W. Martinez, Scott T. Phillips, Nina Jain, George M. Whitesides

Chemistry and Biochemistry

This communication describes a simple method for printing aqueous solutions with millimeter-scale patterns on a variety of substrates using an easily fabricated, paper-based microfluidic device (a paper-based ―stamp‖) as a contact printing device. The device is made from inexpensive materials, and it is easily assembled by hand; this method is thus accessible to a wide range of laboratories and budgets. A single device was used to print over 2500 spots in less than three minutes at a density of 16 spots per square centimetre. This method provides a new tool to pattern biochemicals—reagents, antigens, proteins, and DNA—on planar ...


Spermine Oxidase (Smo) Activity In Breast Tumor Tissues And Biochemical Analysis Of The Anticancer Spermine Analogues Benspm And Cpenspm, Manuela Cervelli, Gabriella Bellavia, Emiliano Fratini, Roberto Amendola, Fabio Polticelli, Marco Barba, Rodolfo Federico, Fabrizio Signore, Giacomo Gucciardo, Rosalba Grillo, Patrick M. Woster, Robert A. Casero Jr, Paolo Mariottini 2010 Dipartimento di Biologia, Università Roma Tre

Spermine Oxidase (Smo) Activity In Breast Tumor Tissues And Biochemical Analysis Of The Anticancer Spermine Analogues Benspm And Cpenspm, Manuela Cervelli, Gabriella Bellavia, Emiliano Fratini, Roberto Amendola, Fabio Polticelli, Marco Barba, Rodolfo Federico, Fabrizio Signore, Giacomo Gucciardo, Rosalba Grillo, Patrick M. Woster, Robert A. Casero Jr, Paolo Mariottini

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Polyamine metabolism has a critical role in cell death and proliferation representing a potential target for intervention in breast cancer (BC). This study investigates the expression of spermine oxidase (SMO) and its prognostic significance in BC. Biochemical analysis of Spm analogues BENSpm and CPENSpm, utilized in anticancer therapy, was also carried out to test their property in silico and in vitro on the recombinant SMO enzyme.

Methods

BC tissue samples were analyzed for SMO transcript level and SMO activity. Student's t test was applied to evaluate the significance of the differences in value observed in T and ...


Structure-Function Relationship Studies Of The Udp-Glucose Pyrophosphorylase From Escherichia Coli, Agnieszka Maria Orlof 2010 Loyola University Chicago

Structure-Function Relationship Studies Of The Udp-Glucose Pyrophosphorylase From Escherichia Coli, Agnieszka Maria Orlof

Master's Theses

UDP-Glucose Pyrophosphorylase (UDP-Glc PPase) is a key enzyme of the carbohydrate metabolic pathway widely used among prokaryotes and eukaryotes. In plants, UDP-Glc PPase is necessary for sucrose synthesis while mammals utilize this enzyme for the production of glycogen. A bacterium such as Escherichia coli uses UDP-Glc PPase for biosynthesis of the lipopolysscharide core which forms a cell wall.

This study focused on UDP-Glc PPase from Escherichia coli which is encoded by both galU and galF genes. The first part of this project investigated amino acids that could play an important role in the function of UDP Glc PPase (GalU). Based ...


Mechanism Of Catch Force: Tethering Of Thick And Thin Filaments By Twitchin., Thomas M Butler, Marion J Siegman 2010 Jefferson Medical College

Mechanism Of Catch Force: Tethering Of Thick And Thin Filaments By Twitchin., Thomas M Butler, Marion J Siegman

Department of Molecular Physiology and Biophysics Faculty Papers

Catch is a mechanical state occurring in some invertebrate smooth muscles characterized by high force maintenance and resistance to stretch during extremely slow relaxation. During catch, intracellular calcium is near basal concentration and myosin crossbridge cyctng rate is extremely slow. Catch force is relaxed by a protein kinase A-mediated phosphorylation of sites near the N- and C- temini of the minititin twitchin (approximately 526 kDa). Some catch force maintenance car also occur together with cycling myosin crossbridges at submaximal calcium concentrations, but not when the muscle is maximally activated. Additionally, the link responsible for catch can adjust during shortening of ...


Ipla2Β, Alternative Splicing And Apoptosis Of Pancreatic Islets, Bhargavi Emani 2010 Virginia Commonwealth University

Ipla2Β, Alternative Splicing And Apoptosis Of Pancreatic Islets, Bhargavi Emani

Theses and Dissertations

Ceramides are bioactive lipids that can promote splicing of apoptosis-related genes, including caspase 9 and BCL-x. A recent study demonstrated that expression of neutral sphingomyelinase (NSMase), an enzyme that hydrolyzes sphingomyelins to generate ceramide, is regulated by Group VIA phospholipase A2 (iPLA2β)-dependent mechanism during β-cell apoptosis. This prompted us to hypothesize that iPLA2 is upstream of ceramide generation in the process regulating splicing of apoptotic genes. To test this, Jurkat T cells were treated with the selective inhibitor of iPLA2β, bromoenol lactone (BEL), RNA was isolated and converted to cDNA, and caspase 9 and BCL-x mRNA viii species were ...


Evolution Of Lactate Dehydrogenase Genes In Primates, With Special Consideration Of Nucleotide Organization In Mammalian Promoters, Zack Papper 2010 Wayne State University

Evolution Of Lactate Dehydrogenase Genes In Primates, With Special Consideration Of Nucleotide Organization In Mammalian Promoters, Zack Papper

Wayne State University Dissertations

Concomitant with an increase in brain volume and mass, the allocation of energetic resources to the brain increased during stem anthropoid evolution, leading to humans. One mechanism by which this allocation may have occurred is through greater use of lactate as a neuronal fuel. Both the production of lactate, and conversion to pyruvate for use in aerobic metabolism, are catalyzed, in part, by the tetrameric enzyme lactate dehydrogenase (LDH). The two primary LDH genes, LDHA and LDHB, confer different rates of substrate turnover to the LDH enzyme, and these rates lend to the argument that LDHA supports anaerobic while LDHB ...


The Roles Of Rhle And Hfq In Srna-Dependent Gene Regulation, Abeykoon Jayalath Iresha Sandeepanie Rathnayake 2010 Wayne State University

The Roles Of Rhle And Hfq In Srna-Dependent Gene Regulation, Abeykoon Jayalath Iresha Sandeepanie Rathnayake

Wayne State University Theses

THE ROLES OF RHLE AND HFQ IN SRNA-DEPENDENT GENE REGULATION

by

ABEYKOON JAYALATH IRESHA SANDEEPANIE RATHNAYAKE

DECEMBER 2010

Advisor: Dr. Andrew Feig

Major: Chemistry

Degree: Master of Science

Bacteria are adapted to live in diverse environmental conditions. Thus, they show excellent tolerance and response to extreme environmental conditions caused by low or high temperatures, high salinity, reactive oxygen species or high nutrient concentrations. sRNAs have been identified and characterized as cis-acting or trans-acting post-transcriptional regulators in diverse cellular processes including virulence and adaptation to environmental stress (11,12,14,15). Interactions of sRNAs and target mRNAs result in translational repression ...


Localization And Functional Analysis Of Plasmodium Falciparum Genes Pfl2550w And Pff0750w, Carolyn Jane Strobel 2010 Loyola University Chicago

Localization And Functional Analysis Of Plasmodium Falciparum Genes Pfl2550w And Pff0750w, Carolyn Jane Strobel

Master's Theses

Malaria is a parasitic disease that causes over a million deaths worldwide each year. Understanding development through the parasite's life cycle is necessary to stop disease transmission. As the genetic basis for the crucial transition from the erythrocytic asexual cycle to gametocytogenesis is unknown, we hope to better understand this transition by studying sexual stage genes and their roles in gametocytogenesis. PFL2550w and PFF0750w are genes upregulated during gametocytogenesis that were identified by a whole-genome microarray comparing gene expression between gametocyte-producing and gametocyte-deficient strains. In this study, PFL2550w was shown to be a soluble protein that is exported from ...


Identification Of Deletion Mutants Of Inositol Kinases And Phosphatases Hypersensitive To Valproate, W-Mudiyanselage Manoj Senaka Bandara 2010 Wayne State University

Identification Of Deletion Mutants Of Inositol Kinases And Phosphatases Hypersensitive To Valproate, W-Mudiyanselage Manoj Senaka Bandara

Wayne State University Theses

ABSTRACT

IDENTIFICATION OF DELETION MUTANTS OF INOSITOL KINASES AND PHOSPHATASES HYPERSENSITIVE TO VALPROATE

by

WELLEWATTA MUDIYANSELAGE MANOJ SENAKA BANDARA

MAY 2010

Advisor: Dr. Miriam Greenberg

Major: Biological Sciences

Degree: Master of Science

Bipolar disorder (BD) is a chronic psychiatric illness affecting at least 1% of the world population. BD is ranked as the sixth greatest cause of death or disability globally. The cause of BD is unknown. Although the anticonvulsant valproate (VPA) is widely used as a mood stabilizer to treat BD, VPA is not completely effective and causes numerous side effects. Hence, it is important to develop more effective ...


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum 2010 University of Richmond

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum

Chemistry Faculty Publications

Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima was found to encode a highly stable and specific periplasmic arginine-binding protein (TM0593). Following signal sequence removal and overexpression in Escherichia coli, TM0593 was purified by thermoprecipitation and affinity chromatography. The ultra-stable protein with a monomeric molecular weight of 27.7 kDa was found to exist as both a homodimer and homotrimer at appreciable concentrations even under strongly denaturing conditions, with an estimated transition temperature of 116 °C. Its multimeric structure may provide further evidence of ...


Hydrogenase-3 Contributes To Anaerobic Acid Resistance Of Escherichia Coli, Joan Slonczewski, Ken Noguchi, Daniel P. Riggins, Khalid C. Eldahan, Ryan D. Kitko 2010 Kenyon College

Hydrogenase-3 Contributes To Anaerobic Acid Resistance Of Escherichia Coli, Joan Slonczewski, Ken Noguchi, Daniel P. Riggins, Khalid C. Eldahan, Ryan D. Kitko

Faculty Publications

Background: Hydrogen production by fermenting bacteria such as Escherichia coli offers a potential source of hydrogen biofuel. Because H2 production involves consumption of 2H+ , hydrogenase expression is likely to involve pH response and regulation. Hydrogenase consumption of protons in E. coli has been implicated in acid resistance, the ability to survive exposure to acid levels (pH 2–2.5) that are three pH units lower than the pH limit of growth (pH 5–6). Enhanced survival in acid enables a larger infective inoculum to pass through the stomach and colonize the intestine. Most acid resistance mechanisms have been defined using ...


Osmolytes Contribute To Ph Homeostasis Of Escherichia Coli, Joan Slonczewski, Ryan D. Kitko, Jessica C. Wilks, Gian M. Garduque 2010 Kenyon College

Osmolytes Contribute To Ph Homeostasis Of Escherichia Coli, Joan Slonczewski, Ryan D. Kitko, Jessica C. Wilks, Gian M. Garduque

Faculty Publications

Background: Cytoplasmic pH homeostasis in Escherichia coli includes numerous mechanisms involving pH-dependent catabolism and ion fluxes. An important contributor is transmembrane K+ flux, but the actual basis of K+ compensation for pH stress remains unclear. Osmoprotection could mediate the pH protection afforded by K+ and other osmolytes. Methods and Principal Findings: The cytoplasmic pH of E. coli K-12 strains was measured by GFPmut3 fluorimetry. The wild-type strain Frag1 was exposed to rapid external acidification by HCl addition. Recovery of cytoplasmic pH was enhanced equally by supplementation with NaCl, KCl, proline, or sucrose. A triple mutant strain TK2420 defective for the ...


On The Mechanism Of Protein Fold-Switching By A Molecular Sensor, Margaret M. Stratton, S N. Loh 2010 University of Massachusetts Amherst

On The Mechanism Of Protein Fold-Switching By A Molecular Sensor, Margaret M. Stratton, S N. Loh

Biochemistry & Molecular Biology Department Faculty Publication Series

Alternate frame folding (AFF) is a mechanism by which conformational change can be engineered into a protein. The protein structure switches from the wild-type fold (N) to a circularly-permuted fold (N'), or vice versa, in response to a signaling event such as ligand binding. Despite the fact that the two native states have similar structures, their interconversion involves folding and unfolding of large parts of the molecule. This rearrangement is reported by fluorescent groups whose relative proximities change as a result of the order-disorder transition. The nature of the conformational change is expected to be similar from protein to protein ...


Stream Invertebrate Responses To A Catastrophic Decline In Consumer Diversity, J. Checo Colón-Gaud, Matt R. Whiles, Karen R. Lips, Catherine M. Pringle, Susan Kilham, Roberto Brenes, Scot D. Peterson 2010 Georgia Southern University

Stream Invertebrate Responses To A Catastrophic Decline In Consumer Diversity, J. Checo Colón-Gaud, Matt R. Whiles, Karen R. Lips, Catherine M. Pringle, Susan Kilham, Roberto Brenes, Scot D. Peterson

Biology Faculty Publications

Tadpoles are often abundant and diverse consumers in headwater streams in the Neotropics. However, their populations are declining catastrophically in many regions, in part because of a chytrid fungal pathogen. These declines are occurring along a moving disease front in Central America and offer the rare opportunity to quantify the consequences of a sudden, dramatic decline in consumer diversity in a natural system. As part of the Tropical Amphibian Declines in Streams (TADS) project, we examined stream macroinvertebrate assemblage structure and production for 2 y in 4 stream reaches at 2 sites in Panama. One site initially had healthy amphibians ...


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