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Sample records for acid dibenzothiophene dbt

  1. Oxidation of dibenzothiophene (DBT) by Serratia marcescens UCP 1549 formed biphenyl as final product

    PubMed Central

    2012-01-01

    Background The desulphurization of dibenzothiophene (DBT), a recalcitrant thiophenic fossil fuel component by Serratia marcescens (UCP 1549) in order for reducing the Sulphur content was investigated. The Study was carried out establishing the growth profile using Luria Bertani medium to different concentrations of DBT during 120 hours at 28°C, and orbital Shaker at 150 rpm. Results The results indicated that concentrations of DBT 0.5, 1.0 and 2.0 mM do not affected the growth of the bacterium. The DBT showed similar Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MCB) (3.68 mM). The desulphurization of DBT by S. marcescens was used with 96 hours of growth on 2 mM of DBT, and was determined by gas chromatography (GC) and GC-mass spectrometry. In order to study the desulphurization process by S. marcescens was observed the presence of a sulfur-free product at 16 hours of cultivation. Conclusions The data suggests the use of metabolic pathway “4S” by S. marcescens (UCP 1549) and formed biphenyl. The microbial desulphurization process by Serratia can be suggest significant reducing sulphur content in DBT, and showed promising potential for reduction of the sulfur content in diesel oil. PMID:22583489

  2. Desulfurization of dibenzothiophene (DBT) by a novel strain Lysinibacillus sphaericus DMT-7 isolated from diesel contaminated soil.

    PubMed

    Bahuguna, Ashutosh; Lily, Madhuri K; Munjal, Ashok; Singh, Ravindra N; Dangwal, Koushalya

    2011-01-01

    A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620) using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively. The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.

  3. Plasmid-mediated degradation of dibenzothiophene by Pseudomonas species

    SciTech Connect

    Monticello, D.J.; Bakker, D.; Finnerty, W.R.

    1985-04-01

    The microbial transformation of dibenzothiophene (DBT) is of interest in the potential desulfurization of oil. The authors isolated three soil Pseuodomonas species which oxidized DBT to characteristic water-soluble, sulfur containing products. Two of the isolates harbored a 55-megadalton plasmid; growth in the presence of novobiocin resulted in both loss of the plasmid and loss of the ability to oxidize DBT. Reintroduction of the plasmid restored the ability to oxidize DBT to water-soluble products. The products resulting from the oxidation of DBT were characterized and included 3-hydroxy-2-formyl benzothiophene, 3-oxo-(3'-hydroxy-thionaphthenyl-(2)-methylene)-dihydrothionaphthene, and the hemiacetal and trans forms of 4-(2-(3-hydroxy)-thianaphthenyl)-2-oxo-3-butenoic acid. The products of DBT oxidation were inhibitory to cell growth and further DBT oxidation. DBT oxidation in the soil isolates was induced by naphthalene or salicylate and to a much lesser extent by DBT and was repressed by succinate.

  4. On the mechanism of reactive adsorption of dibenzothiophene on organic waste derived carbons

    NASA Astrophysics Data System (ADS)

    Ania, C. O.; Parra, J. B.; Arenillas, A.; Rubiera, F.; Bandosz, T. J.; Pis, J. J.

    2007-04-01

    The mechanism of reactive adsorption of dibenzothiophene (DBT) on a series of modified carbons derived from the recycled PET was investigated. The influence of the oxygen functionalities of the adsorbent on the DBT adsorption capacity was explored. The results revealed that adsorption of DBT on activated carbons is governed by two types of contributions: physisorption on the microporous network of the carbons and chemisorption. Introduction of surface acidic groups enhanced the performance of the carbons as a result of their specific interactions with DBT. The nature of the acidic groups is a decisive factor in the selectivity of the reactive adsorption process.

  5. Plasmid-mediated degradation of dibenzothiophene by Pseudomonas species.

    PubMed

    Monticello, D J; Bakker, D; Finnerty, W R

    1985-04-01

    The microbial transformation of dibenzothiophene (DBT) is of interest in the potential desulfurization of oil. We isolated three soil Pseudomonas species which oxidized DBT to characteristic water-soluble, sulfur-containing products. Two of our isolates harbored a 55-megadalton plasmid; growth in the presence of novobiocin resulted in both loss of the plasmid and loss of the ability to oxidize DBT. Reintroduction of the plasmid restored the ability to oxidize DBT to water-soluble products. The products resulting from the oxidation of DBT were characterized and included 3-hydroxy-2-formyl benzothiophene, 3-oxo-[3'-hydroxy-thionaphthenyl-(2)-methylene]-dihydrothionaph thene, and the hemiacetal and trans forms of 4-[2-(3-hydroxy)-thianaphthenyl]-2-oxo-3-butenoic acid. The products of DBT oxidation were inhibitory to cell growth and further DBT oxidation. DBT oxidation in our soil isolates was induced by naphthalene or salicylate and to a much lesser extent by DBT and was repressed by succinate.

  6. Desulfurization of dibenzothiophene by a newly isolated Corynebacterium sp. ZD-1 in aqueous phase.

    PubMed

    Wang, Miao-Dong; Li, Wei; Wang, Da-Hui; Shi, Yao

    2004-01-01

    Sulfur emission through fuel combustion is a global problem because it is a major cause of acid rain. Crud oil contains many heterocyclic organic sulfur compounds, among which dibenzothiophene (DBT) and DBTs bearing alkyl substitutions usually are representative compounds. A strain was isolated from refinery sludge and identified as Corynebacterium ZD-1. The behavior of DBT degradation by ZD-1 in aqueous phase was investigated. Corynebacterium ZD-1 could metabolize DBT to 2-hydroxybiphenyl(2-HBP) as the dead-end metabolite through a sulfur-specific pathway. In shake flask culture, ZD-1 had its maximal desulfurization activity in the late exponential growth phase and the specific production rate of 2-HBP was about 0.14 (mmol x kg dry cell(-1) x min(-1), mmol x KDC(-1) x min(-1)). Active resting cells for desulfurization should be prepared only in this period. 2-HBP inhibited the growth of strain ZD-1, the production of DBT degradation enzymes, and the activity of enzymes. Sulfate inhibited the production of dibenzothiophene (DBT) degradation enzymes but had no effect on the enzymes' activity. The production rates of 2-HBP at lower cell densities were higher and the maximum amount conversion of DBT to 2-HBP (0.067 mmol/L) after 8 h was gained at 9.2 g dry cell/L rather higher cell density. The results indicated that this newly isolated strain could be a promising biocatalyst for DBT desulfurization.

  7. Aerobic biodegradation of 2,2'-dithiodibenzoic acid produced from dibenzothiophene metabolites

    SciTech Connect

    Young, R.F.; Cheng, S.M.; Fedorak, P.M.

    2006-01-15

    Dibenzothiophene is a sulfur heterocycle found in crude oils and coal. The biodegradation of dibenzothiophene through the Kodama pathway by Pseudomonas sp. strain BT1d leads to the formation of three disulfides: 2-oxo-2-(2-thiophenyl)ethanoic acid disulfide, 2-oxo-2-(2-thiophenyl)ethanoic acid-2-benzoic acid disulfide, and 2,2'-dithiodibenzoic acid. When provided as the carbon and sulfur source in liquid medium, 2,2'-dithiodibenzoic acid was degraded by soil enrichment cultures. Two bacterial isolates, designated strains RM1 and RM6, degraded 2,2'-dithiodibenzoic acid when combined in the medium. Isolate RM6 was found to have an absolute requirement for vitamin B{sub 12}, and it degraded 2,2'-dithiodibenzoic acid in pure culture when the medium was supplemented with this vitamin. Isolate RM6 also degraded 2,2'-dithiodibenzoic acid in medium containing sterilized supernatants from cultures of isolate RM1 grown on glucose or benzoate. Isolate RM6 was identified as a member of the genus Variovorax using the Biolog system and 16S rRNA gene analysis. Although the mechanism of disulfide metabolism could not be determined, benzoic acid was detected as a transient metabolite of 2,2'-dithiodibenzoic acid biodegradation by Variovorax sp. strain RM6. In pure culture, this isolate mineralized 2,2'-dithiodibenzoic acid, releasing 59% of the carbon as carbon dioxide and 88% of the sulfur as sulfate.

  8. Kinetics of dibenzothiophene hydrodesulfurization

    SciTech Connect

    Ho, T.C.; Sobel, J.E. )

    1991-04-01

    Hydrotreating is a process in which organically bound sulfur and nitrogen compounds are removed from petroleum feedstocks to produce processible, stable, and environmentally acceptable liquid fuels or lubes. Essentially two types of catalysts, which differ in composition, are in use in current refineries: one is sulfided CoO-MoO{sub 3}/{gamma}-Al{sub 2}O{sub 3}, the other sulfided NiO-MoO{sub 3}/Al{sub 2}O{sub 3}. The selection of these catalysts depends largely on the processing objectives and the nature of the feedstocks. Generally speaking, the NiMo catalysts are used for hydrodenitrogenation (HDN) and hydrodearomatization (HDA), while the CoMo catalysts are used for hydrodesulfurization (HDS). HDS of dibenzothiophene (DBT) is a useful model reaction for HDS of commercial middle distillate feedstocks. In a previous study, Ho et al. quantified the interactions between HDN and HDA on a commercial NiMo catalyst by using a feed mixture containing 2,4-dimethyl pyridine and 2-methylnaphthalene. With the same catalyst, here we determine the kinetics of DBT HDS. Another reason for undertaking the present study is that relatively little attention has been paid to DBT HDS on NiMo catalysts. Most published DBT HDS studies have been done on CoMo catalysts.

  9. Enhancement in dibenzothiophene reactive adsorption from liquid fuel via incorporation of sulfur heteroatoms into the nanoporous carbon matrix.

    PubMed

    Seredych, Mykola; Khine, Monmon; Bandosz, Teresa J

    2011-01-17

    Adsorption of dibenzothiophene (DBT) and 4,6-dimethyldibenzothiophene (DMDBT) from simulated diesel fuel was investigated with polymer-derived carbon matrices. Sulfur was incorporated to the carbon surface via a high-temperature hydrogen sulfide reduction of oxygen-containing groups. The resultant carbons were characterized by nitrogen adsorption, thermal analysis, potentiometric titration, and elemental analysis. The selectivities for DBT and DMDBT adsorption were calculated with reference to naphthalene. The carbon matrices studied had comparable structures, hence, the effects of the sulfur functionalities were evident in an increase in dibenzothiophenes selectivity and the breakthrough capacity; this was especially visible at a breakthrough point where small pores are expected to be active in the adsorption process. Incorporation of sulfur atoms into the aromatic rings of the carbon matrix increases the ability of the surface to attract dibenzothiophenes via dispersive interactions (sulfur-sulfur bridges). Sulfur and sulfur-oxygen groups present in larger pores enhance the amount of adsorbed dibenzothiophenes via specific acid-base and polar interactions. They also contribute to the reactive adsorption of DBT and DMDBT (oxidized) and their chemisorption on the carbon surface.

  10. Efficient dibutyltin (DBT) elimination by the microscopic fungus Metarhizium robertsii under conditions of intensive aeration and ascorbic acid supplementation.

    PubMed

    Siewiera, Paulina; Różalska, Sylwia; Bernat, Przemysław

    2017-03-27

    Dibutyltin (DBT) is an environmental pollutant characterized by immunotoxic, neurotoxic, and pro-oxidant properties. In this study, an attempt was made to enhance DBT elimination by the Metarhizium robertsii strain. We observed enhanced fungal growth in the bioreactor (pO2 ≥ 20%) compared to flask cultures (μ max increased from 0.061 to 0.086 h(-1)). Moreover, under aerated conditions, M. robertsii mycelium with "hairy" morphology biodegraded DBT (20 mg l(-1)) 10-fold faster in the bioreactor than in the flask cultures. Monobutyltin (MBT) and a hydroxylated derivative of MBT (OHBuSnH2) were detected as by-products of dibutyltin debutylation. Simultaneous usage of glucose and butyltins indicates the comatabolic nature of monobutyltin and dibutyltin removal. In order to protect fungal cells from oxidative stress caused by DBT presence, vitamin C (20 mg l(-1)) was applied. Supplementation with ascorbic acid (AA) resulted in a 3-fold acceleration of MBT removal during the first 7 h of incubation. Using the HPLC-MS/MS technique, a quantitative analysis of malondialdehyde (MDA), a marker of oxidative stress, was performed. In the AA presence, a decrease in the MDA amount (about 45%) was observed compared to the case with fungal cells exposed to DBT alone.

  11. Sequence and molecular characterization of a DNA region encoding the dibenzothiophene desulfurization operon of Rhodococcus sp. strain IGTS8.

    PubMed

    Piddington, C S; Kovacevich, B R; Rambosek, J

    1995-02-01

    Dibenzothiophene (DBT), a model compound for sulfur-containing organic molecules found in fossil fuels, can be desulfurized to 2-hydroxybiphenyl (2-HBP) by Rhodococcus sp. strain IGTS8. Complementation of a desulfurization (dsz) mutant provided the genes from Rhodococcus sp. strain IGTS8 responsible for desulfurization. A 6.7-kb TaqI fragment cloned in Escherichia coli-Rhodococcus shuttle vector pRR-6 was found to both complement this mutation and confer desulfurization to Rhodococcus fascians, which normally is not able to desulfurize DBT. Expression of this fragment in E. coli also conferred the ability to desulfurize DBT. A molecular analysis of the cloned fragment revealed a single operon containing three open reading frames involved in the conversion of DBT to 2-HBP. The three genes were designated dszA, dszB, and dszC. Neither the nucleotide sequences nor the deduced amino acid sequences of the enzymes exhibited significant similarity to sequences obtained from the GenBank, EMBL, and Swiss-Prot databases, indicating that these enzymes are novel enzymes. Subclone analyses revealed that the gene product of dszC converts DBT directly to DBT-sulfone and that the gene products of dszA and dszB act in concert to convert DBT-sulfone to 2-HBP.

  12. Phenolic resin-derived activated carbon-supported divalent metal as efficient adsorbents (M-C, M=Zn, Ni, or Cu) for dibenzothiophene removal.

    PubMed

    He, Chi; Men, Gaoshan; Xu, Bitao; Cui, Jin; Zhao, Jinglian

    2017-01-01

    The adsorption process and mechanism of dibenzothiophene (DBT) over metal-loaded phenolic resin-derived activated carbon (PR-AC) were firstly reported in this work. The metal component (Zn, Ni, or Cu) was respectively introduced to PR-AC support via an impregnation method. The effects of adsorbent component, initial DBT concentration, liquid hourly space velocity (LHSV), adsorption time, and adsorption temperature on the adsorption capacity of the adsorbents were systematically investigated. Furthermore, the adsorption mechanism was discussed by analyzing the properties of adsorption product and saturated adsorbent as well as adsorption kinetics. Experimental results indicate that the PR-AC-loaded metal adsorbents, especially with Zn, present much higher DBT adsorption capability than that of pure PR-AC support. The DBT removal rate over PR-AC-loaded Zn (Zn(2+) = 0.2 mol L(-1)) reaches 89.14 %, which is almost twice higher than that of pure PR-AC (45.6 %). This is due to the π-complexation between DBT and metal ions (dominating factor) and the weakening of the local hard acid sites over PR-AC. The multi-factor orthogonal experiment shows that the DBT removal rate over PR-AC-loaded Zn sample achieved 92.36 % in optimum conditions.

  13. Oxidative desulfurization of dibenzothiophene from model oil using ionic liquids as extracting agent

    NASA Astrophysics Data System (ADS)

    Taha, Mohd F.; Atikah, N.; Chong, F. K.; Shaharun, Maizatul S.

    2012-09-01

    The oxidative desulfurization of dibenzothiophene (DBT) from model oil (in n-dodecane) was carried out using ionic liquid as the extractant and catalyst, and hydrogen peroxide (H2O2) in combination with acetic acid (CH3COOH) and sulphuric acid (H2SO4) as the oxidant. The ionic liquids used were 1-butyl-3-methylimidazolium octyl sulphate ([Bmim][OcSO4]) and 1-butyl-3-methylimidazolium acetate ([Bmim][Ac]). The effect of the amounts of H2O2 on oxidative desulphurization of model oil was first investigated without the usage of ionic liquids at room temperature. The results indicate that greater amount of H2O2 give higher desulfurization and the maximum desulfurization in this study, i.e. 34 %, was occurred when the molar ratio of H2O2 to sulfur was 5:1. With the usage of ionic liquid and the molar ratio of 5:1 (H2O2:sulfur), the efficiency of DBT removal from model oil was increased significantly in terms of percent removal and removal time. Ionic liquid of [Bmim][OcSO4] performed better than [Bmim][Ac] with 72 % DBT removal. When molar ratio of H2O2 to sulphur was 5:1, volume ratio of ionic liquid to model oil was 1:1 and mixing time was 60 min at room temperature. The results indicate the potential of ionic liquids as the extractant and catalyst for oxidative desulfurization of hydrocarbon fuels.

  14. Surface chemistry and catalytic properties of VOX/Ti-MCM-41 catalysts for dibenzothiophene oxidation in a biphasic system

    NASA Astrophysics Data System (ADS)

    González, J.; Chen, L. F.; Wang, J. A.; Manríquez, Ma.; Limas, R.; Schachat, P.; Navarrete, J.; Contreras, J. L.

    2016-08-01

    A series of vanadium oxide supported on Ti-MCM-41 catalysts was synthesized via the incipient impregnation method by varying the vanadia loading from 5 wt% to 10, 15, 20 and 25 wt%. These catalysts were characterized by a variety of advanced techniques for investigating their crystalline structure, textural properties, and surface chemistry information including surface acidity, reducibility, vanadium oxidation states, and morphological features. The catalytic activities of the catalysts were evaluated in a biphasic reaction system for oxidative desulfurization (ODS) of a model diesel containing 300 ppm of dibenzothiophene (DBT) where acetonitrile was used as extraction solvent and H2O2 as oxidant. ODS activity was found to be proportional to the V5+/(V4+ + V5+) values of the catalysts, indicating that the surface vanadium pentoxide (V2O5) was the active phase. Reaction temperature would influence significantly the ODS efficiency; high temperature, i.e., 80 °C, would lead to low ODS reaction due to the partial decomposition of oxidant. All the catalysts contained both Lewis and Brønsted acid sites but the former was predominant. The catalysts with low vanadia loading (5 or 10 wt%V2O5) had many Lewis acid sites and could strongly adsorb DBT molecule via the electron donation/acceptance action which resulted in an inhibition for the reaction of DBT with the surface peroxometallic species. The catalyst with high vanadia loading (25wt%V2O5/Ti-MCM-41) showed the highest catalytic activity and could remove 99.9% of DBT at 60 °C within 60 min.

  15. Purification, Characterization, and Overexpression of Flavin Reductase Involved in Dibenzothiophene Desulfurization by Rhodococcus erythropolis D-1

    PubMed Central

    Matsubara, Toshiyuki; Ohshiro, Takashi; Nishina, Yoshihiro; Izumi, Yoshikazu

    2001-01-01

    The dibenzothiophene (DBT)-desulfurizing bacterium, Rhodococcus erythropolis D-1, removes sulfur from DBT to form 2-hydroxybiphenyl using four enzymes, DszC, DszA, DszB, and flavin reductase. In this study, we purified and characterized the flavin reductase from R. erythropolis D-1 grown in a medium containing DBT as the sole source of sulfur. It is conceivable that the enzyme is essential for two monooxygenase (DszC and DszA) reactions in vivo. The purified flavin reductase contains no chromogenic cofactors and was found to have a molecular mass of 86 kDa and four identical 22-kDa subunits. The enzyme catalyzed NADH-dependent reduction of flavin mononucleotide (FMN), and the Km values for NADH and FMN were 208 and 10.8 μM, respectively. Flavin adenine dinucleotide was a poor substrate, and NADPH was inert. The enzyme did not catalyze reduction of any nitroaromatic compound. The optimal temperature and optimal pH for enzyme activity were 35°C and 6.0, respectively, and the enzyme retained 30% of its activity after heat treatment at 80°C for 30 min. The N-terminal amino acid sequence of the purified flavin reductase was identical to that of DszD of R. erythropolis IGTS8 (K. A. Gray, O. S. Pogrebinsky, G. T. Mrachko, L. Xi, D. J. Monticello, and C. H. Squires, Nat. Biotechnol. 14:1705–1709, 1996). The flavin reductase gene was amplified with primers designed by using dszD of R. erythropolis IGTS8, and the enzyme was overexpressed in Escherichia coli. The specific activity in crude extracts of the overexpressed strain was about 275-fold that of the wild-type strain. PMID:11229908

  16. Metabolism of dibenzothiophene by a Beijerinckia species.

    PubMed Central

    Laborde, A L; Gibson, D T

    1977-01-01

    Beijerinckia B8/36 when grown with succinate in the presence of dibenzothiophene, accumulated (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene and dibenzothiophene-5-oxide in the culture medium. Each metabolite was isolated in crystalline form and characterized by a variety of chemical techniques, cis-Naphthalene dihydrodiol dehydrogenase, isolated from Pseudomonas putida, oxidized (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene to a compound that was tentatively identified as 1,2-dihydroxydibenzothiophene. The same product was formed when crude cell extracts of the parent strain of Beijerinckia oxidized (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene under anaerobic conditions. Further metabolism of 1,2-dihydroxydibenzothiophene by heat-treated cell extracts led to the formation of 4[2-(3-hydroxy)-thionaphthenyl]-2-oxo-3-butenoic acid. The latter compound was metabolized by crude cell extracts to 3-hydroxy-2-formylthionaphthene. Further degradation of this metabolite was not observed. PMID:596875

  17. Metabolism of dibenzothiophene by a Beijerinckia species.

    PubMed

    Laborde, A L; Gibson, D T

    1977-12-01

    Beijerinckia B8/36 when grown with succinate in the presence of dibenzothiophene, accumulated (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene and dibenzothiophene-5-oxide in the culture medium. Each metabolite was isolated in crystalline form and characterized by a variety of chemical techniques, cis-Naphthalene dihydrodiol dehydrogenase, isolated from Pseudomonas putida, oxidized (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene to a compound that was tentatively identified as 1,2-dihydroxydibenzothiophene. The same product was formed when crude cell extracts of the parent strain of Beijerinckia oxidized (+)-cis-1,2-dihydroxy-1,2-dihydrodibenzothiophene under anaerobic conditions. Further metabolism of 1,2-dihydroxydibenzothiophene by heat-treated cell extracts led to the formation of 4[2-(3-hydroxy)-thionaphthenyl]-2-oxo-3-butenoic acid. The latter compound was metabolized by crude cell extracts to 3-hydroxy-2-formylthionaphthene. Further degradation of this metabolite was not observed.

  18. SULFUR REDUCTION IN GASOLINE AND DIESEL FUELS BY EXTRACTION/ADSORPTION OF REFRACTORY DIBENZOTHIOPHENES

    SciTech Connect

    Robert J. Angelici

    2003-06-01

    Refractory 4,6-dimethyldibenzothiophene, which is difficult to remove from petroleum feedstocks, binds to the Ru in Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} by displacing the H{sub 2}O ligand. Thiophene, benzothiophene and dibenzothiophene (DBT) also react with Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} similarly. This binding ability of Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} has been used to remove over 50% of the DBT in simulated petroleum feedstocks by a biphasic extraction process. The extraction phase is readily regenerated by air-oxidation thereby completing a cyclic process that removes DBT from petroleum feedstocks. Solid phase extractants consisting of Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+}, CpRu(CO){sub 2}(BF{sub 4}), CpFe(CO){sub 2}(C{sub 4}H{sub 8}){sup +} and AgX (where X = BF{sub 4}{sup -}, PF{sub 6}{sup -} or NO{sub 3}{sup -}) adsorbed on silica have also been used to remove DBT and 4,6-Me{sub 2}DBT from simulated petroleum feedstocks. The AgX/silica adsorbents remove 90% of the DBT and 4,6-Me{sub 2}DBT and can be regenerated and re-used for multiple extractions, which makes these adsorbents of potential industrial use for the removal of refractory dibenzothiophenes from petroleum feedstocks.

  19. Enhancement of dibenzothiophene desulfurization by Gordonia alkanivorans strain 1B using sugar beet molasses as alternative carbon source.

    PubMed

    Alves, Luís; Paixão, Susana M

    2014-03-01

    There are several problems limiting an industrial application of fossil fuel biodesulfurization, and one of them is the cost of culture media used to grow the microorganisms involved in the process. In this context, the utilization of alternative carbon sources resulting from agro-industrial by-products could be a strategy to reduce the investment in the operating expenses of a future industrial application. Recently, Gordonia alkanivorans 1B was described as a fructophilic desulfurizing bacterium, and this characteristic opens a new interest in alternative carbon sources rich in fructose. Thus, the goal of this study was to evaluate the utilization of sugar beet molasses (SBM) in the dibenzothiophene (DBT) desulfurization process using strain 1B. SBM firstly treated with 0.25% BaCl2 (w/v) was used after sucrose acidic hydrolysis or in a simultaneous saccharification and fermentation process with a Zygosaccharomyces bailii Talf1 invertase (1%), showing promising results. In optimal conditions, strain 1B presented a μ max of 0.0795 h(-1), and all DBT was converted to 2-hydroxybiphenyl (250 μM) within 48 h with a maximum production rate of 7.78 μM h(-1). Our results showed the high potential of SBM to be used in a future industrial fossil fuel biodesulfurization process using strain 1B.

  20. Deep extractive and oxidative desulfurization of dibenzothiophene with C5H9NO·SnCl2 coordinated ionic liquid.

    PubMed

    Li, Fa-tang; Kou, Cheng-guang; Sun, Zhi-min; Hao, Ying-juan; Liu, Rui-hong; Zhao, Di-shun

    2012-02-29

    A new C5H9NO·SnCl2 coordinated ionic liquid (IL) was prepared by reacting N-methyl-pyrrolidone with anhydrous SnCl2. Desulfurization of dibenzothiophene (DBT) via extraction and oxidation with C5H9NO·SnCl2 IL as extractant, H2O2 and equal mol of CH3COOH as oxidants was investigated. The Nernst partition coefficients k(N) of C5H9NO·SnCl2 IL for the DBT in n-octane was above 5.0, showing its excellent extraction ability. During the oxidative desulfurization process, the optimal molar ratio of H2O2/DBT was six. Sulfur removal of DBT in n-octane was 94.8% in 30 min at 30 °C under the conditions of H2O2/DBT molar ratio of six and V (IL):V (oil)=1:3. Moreover, the sulfur removal increased with increasing temperature because of the high reaction rate constant, low viscosity, and high solubility of dibenzothiophene-sulfone in the IL. The kinetics of oxidative desulfurization of DBT was also investigated, and the apparent activation energy was found to be 32.5 kJ/mol. The IL could be recycled six times without a significant decrease in activity.

  1. Identification and cloning of genes involved in specific desulfurization dibenzothiophene by Rhodococcus sp. strain IGTS8

    SciTech Connect

    Denome, S.A.; Young, K.D.; Olson, E.S. )

    1993-09-01

    The presence of sulfur in coal and petroleum contributes to corrosion of production and refining equipment and burning these high-sulfur products emits sulfur oxides to the atmosphere. Microorganisms that can enzymatically release organically bound sulfur from organic components of coal or petroleum or from dibenzothiophene (DBT) could reduce the sulfur content of high sulfur fuels without depleting their British thermal unit value. Two major pathways for microbial metabolism of DBT have been proposed. Some of the genes for the DPT degradative pathway have been isolated and characterized. However, no genes for the desulfurization pathway have been identified. This paper reports the isolation from Rhodoccus sp. strain IGTS8 pf a set of genes that confer a specific desulfurization phenotype to mutants and to a related organism, R. fascians D188-5, that is normally unable to desulfurize DBT. 38 refs., 2 figs., 1 tab.

  2. SULFUR REDUCTION IN GASOLINE AND DIESEL FUELS BY EXTRACTION/ADSORPTION OF REFRACTORY DIBENZOTHIOPHENES

    SciTech Connect

    Robert J. Angelici; Scott G. McKinley; Celedonio Alvarez

    2001-10-01

    Using the classical coordination compound, Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+}, they have prepared a metal complex with a 4,6-dimenthyldibenzothiophene ligand. The compound Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} also reacts with thiophene, benzothiophene and dibenzothiophene (DBT) at room temperature. They have found that Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} removes over 50% of the DBT in simulated petroleum feedstocks by a biphasic extraction process. The extraction phase is readily generated by air-oxidation thereby completing a cyclic process that removes DBT from petroleum feedstocks.

  3. Synthesis of silver sulfide modified carbon materials for adsorptive removal of dibenzothiophene in n-hexane.

    PubMed

    Nazal, Mazen K; Khaled, Mazen; Aljundi, Isam H; Atieh, Muataz; Oweimreen, Ghassan A; Abulkibash, Abdalla M

    2017-02-10

    Carbon nanotube (CNT) and graphene oxide (GO) as common nanostructures were modified with silver sulfide (Ag2S) using chemical vapor deposition. The raw and modified materials were tested for the removal of Dibenzothiophene (DBT) from a model fuel in batch mode adsorption experiments. The maximum adsorption capacities of DBT were 52.18 and 49.65 mg g(-1), using CNT-Ag2S and GO-Ag2S, respectively. The adsorption isotherm was modeled using Freundlich, Langmuir and Temkin models using linear and non-linear regression. The squared correlation coefficient (R(2)) and HYBRID error function were used to determine the best adsorption model. IR spectroscopy was used to study the DBT adsorption mechanism, and it was found that the DBT molecules lie flat on the surface of the developed adsorbents. Significant improvement was achieved in the adsorption of DBT using CNT-Ag2S and GO-Ag2S, where the maximum adsorption capacity increased by 127% and 117% respectively, which indicates a stronger interaction between DBT and the modified adsorbents.

  4. Dibenzothiophene adsorption at boron doped carbon nanoribbons studied within density functional theory

    NASA Astrophysics Data System (ADS)

    López-Albarrán, P.; Navarro-Santos, P.; Garcia-Ramirez, M. A.; Ricardo-Chávez, J. L.

    2015-06-01

    The adsorption of dibenzothiophene (DBT) on bare and boron-doped armchair carbon nanoribbons (ACNRs) is being investigated in the framework of the density functional theory by implementing periodic boundary conditions that include corrections from dispersion interactions. The reactivity of the ACNRs is characterized by using the Fukui functions as well as the electrostatic potential as local descriptors. Non-covalent adsorption mechanism is found when using the local Perdew-Becke-Ernzerhof functional, regardless of the DBT orientation and adsorption location. The dispersion interactions addition is a milestone to describe the adsorption process. The charge defects introduced in small number (i.e., by doping with B atoms), within the ACNRs increases the selectivity towards sulfur mainly due to the charge depletion at B sites. The DBT magnitude in the adsorption energy shows non-covalent interactions. As a consequence, the configurations where the DBT is adsorbed on a BC3 island increase the adsorption energy compared to random B arrangements. The stability of these configurations can be explained satisfactorily in terms of dipole interactions. Nevertheless, from the charge-density difference analysis and the weak Bader charge-distribution interactions cannot be ruled out completely. This is why the electronic properties of the ribbons are analyzed in order to elucidate the key role played by the B and DBT states in the adsorbed configurations.

  5. Dibenzothiophene adsorption at boron doped carbon nanoribbons studied within density functional theory

    SciTech Connect

    López-Albarrán, P.; Navarro-Santos, P.; Garcia-Ramirez, M. A.; Ricardo-Chávez, J. L.

    2015-06-21

    The adsorption of dibenzothiophene (DBT) on bare and boron-doped armchair carbon nanoribbons (ACNRs) is being investigated in the framework of the density functional theory by implementing periodic boundary conditions that include corrections from dispersion interactions. The reactivity of the ACNRs is characterized by using the Fukui functions as well as the electrostatic potential as local descriptors. Non-covalent adsorption mechanism is found when using the local Perdew-Becke-Ernzerhof functional, regardless of the DBT orientation and adsorption location. The dispersion interactions addition is a milestone to describe the adsorption process. The charge defects introduced in small number (i.e., by doping with B atoms), within the ACNRs increases the selectivity towards sulfur mainly due to the charge depletion at B sites. The DBT magnitude in the adsorption energy shows non-covalent interactions. As a consequence, the configurations where the DBT is adsorbed on a BC{sub 3} island increase the adsorption energy compared to random B arrangements. The stability of these configurations can be explained satisfactorily in terms of dipole interactions. Nevertheless, from the charge-density difference analysis and the weak Bader charge-distribution interactions cannot be ruled out completely. This is why the electronic properties of the ribbons are analyzed in order to elucidate the key role played by the B and DBT states in the adsorbed configurations.

  6. Microbial-electrochemical bioremediation and detoxification of dibenzothiophene-polluted soil.

    PubMed

    Rodrigo, Jose; Boltes, Karina; Esteve-Nuñez, Abraham

    2014-04-01

    Bioremediation is a relatively efficient and cost-effective technology for treating polluted soils. However, the availability of suitable electron acceptors to sustain microbial respiration can reduce the microbial activity. This work aims to evaluate the impact of burying electrically conductive electron acceptors in soil for enhancing the removal of dibenzothiophene (DBT) by native electrogenic microbes. Although this novel approach is based on the use of a microbial electrochemical technology as microbial fuel cells, our goal is not to harvest energy but to maximize bioremediation, so we concluded to name the device as Microbial Electroremediating Cell (MERC). Our results proved that stimulating the microbial electrogenic metabolism, DBT removal was enhanced by more than 3-fold compared to the natural attenuation. On top of that, ecotoxicological test using green algae confirms a decrease of 50% in the toxicity of the treated soil during incubation in MERC, in contrast to the unaltered values detected under natural conditions.

  7. Synthesis of MoS(2) nanorods and their catalytic test in the HDS of dibenzothiophene.

    PubMed

    Albiter, M A; Huirache-Acuña, R; Paraguay-Delgado, F; Rico, J L; Alonso-Nuñez, G

    2006-07-28

    Partially sulfided nanostructures were synthesized by direct sulfurization of alpha-MoO(3) nanorods using a mixture of H(2)S/H(2), 15 vol%, at several temperatures (400, 500, 600, 700, and 800 degrees C). These materials were tested as catalysts in the hydrodesulfurization (HDS) of dibenzothiophene (DBT) and characterized by specific surface areas using the expression developed by Brunauer, Emmett, and Teller (BET equation), x-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The TEM images show a gradual evolution from a smooth surface to a rough material, presenting some type of holes all over the particles, but keeping their rod-like structure throughout sulfidation. The results of evaluating the catalysts in the HDS of DBT showed that the best temperature for sulfidation is 500 degrees C. In all samples, a higher selectivity for hydrogenation over sulfur removal was observed.

  8. A comparison of the response of two Burkholderia fungorum strains grown as planktonic cells versus biofilm to dibenzothiophene and select polycyclic aromatic hydrocarbons.

    PubMed

    Khoei, Nazanin Seyed; Andreolli, Marco; Lampis, Silvia; Vallini, Giovanni; Turner, Raymond J

    2016-10-01

    In natural environments, bacteria often exist in close association with surfaces and interfaces by establishing biofilms. Here, we report on the ability of Burkholderia fungorum strains DBT1 and 95 to survive in high concentrations of hydrocarbons, and we compare their growth as a biofilm vs. planktonic cells. The 2 compounds tested were dibenzothiophene (DBT) and a mixture of naphthalene, phenanthrene, and pyrene (5:2:1) as representative compounds of thiophenes and polycyclic aromatic hydrocarbons (PAHs), respectively. The results showed that both strains were able to degrade DBT and to survive in the presence of up to a 2000 mg·L(-1) concentration of this compound both as a biofilm and as free-living cells. Moreover, B. fungorum DBT1 showed reduced tolerance towards the mixed PAHs (2000 mg·L(-1) naphthalene, 800 mg·L(-1) phenanthrene, and 400 mg·L(-1) pyrene) both as a biofilm and as free-living cells. Conversely, biofilms of B. fungorum 95 enhanced resistance against these toxic compounds compared with planktonic cells (P < 0.05). Visual observation through confocal laser scanning microscopy showed that exposure of biofilms to DBT and PAHs altered their structure: high concentrations of DBT triggered an aggregation of biofilm cells. These findings provide new perspectives on the effectiveness of using DBT-degrading bacterial strains in bioremediation of hydrocarbon-contaminated sites.

  9. SULFUR REDUCTION IN GASOLINE AND DIESEL FUELS BY EXTRACTION/ADSORPTION OF REFRACTORY DIBENZOTHIOPHENES

    SciTech Connect

    Scott G. McKinley; Celedonio M. Alvarez

    2003-03-01

    The purpose of this study was to remove thiophene, benzothiophene and dibenzothiophene from a simulated gasoline feedstock. We found that Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} reacts with a variety of thiophenes (Th*), affording Ru(NH{sub 3}){sub 5}(Th*){sup 2+}. We used this reactivity to design a biphasic extraction process that removes more than 50% of the dibenzothiophene in the simulated feedstock. This extraction system consists of a hydrocarbon phase (simulated petroleum feedstock) and extractant Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+} in an aqueous phase (70% dimethylformamide, 30% H{sub 2}O). The DBT is removed in situ from the newly formed Ru(NH{sub 3}){sub 5}(DBT){sup 2+} by either an oxidation process or addition of H{sub 2}O, to regenerate Ru(NH{sub 3}){sub 5}(H{sub 2}O){sup 2+}.

  10. The enhanced adsorption of dibenzothiophene onto cerium/nickel-exchanged zeolite Y.

    PubMed

    Wang, Juan; Xu, Fang; Xie, Wei-jie; Mei, Zhi-jian; Zhang, Qiu-zhuo; Cai, Jun; Cai, Wei-min

    2009-04-30

    The investigations for selective adsorption of dibenzothiophene (DBT) over Ce/Ni-loaded Y zeolites with the emphasis on the effect of Ce as a cocation in the Ni-loaded Y zeolite are carried out in an attempt to produce more effective adsorbents for the desulfurization from transportation fuels. The promotional effects of Ce and coexisting toluene in the model fuel as well as contact time and adsorbent dose on the adsorptive performance were examined. The sulfur uptake strongly depends on the amount of Ce in the zeolite structure. The sorption data is varied according to both Langmuir and Freundlich isotherm models. The maximum sorption capacity by theoretically calculation is 22.2mg/g at 25 degrees C. The Langmuir constants b=5.82 mL/mg and the Freundlich constants K=1.042 L/mg and 1/n=0.4 are evaluated. Ni/Ce-loaded Y zeolites (NiCeY) and NiY, CeY, NaY zeolites were used as adsorbents for the removal of DBT from model fuel containing 500 mg/L sulfur with 5 vol% of toluene by a batch method under ambient conditions. NiCeY exhibits higher adsorptive selectivity for DBT than NiY and CeY, indicating that NiCeY is a more effective adsorbent to remove sulfur compounds from transportation fuels.

  11. Synthesis and Lanthanide Coordination Chemistry of Phosphine Oxide Decorated Dibenzothiophene and Dibenzothiophene Sulfone Platforms

    SciTech Connect

    Rosario-Amorin, Daniel; Ouizem, Sabrina; Dickie, D. A.; Paine, Robert T.; Cramer, Roger E.; Hay, Benjamin; Podair, Julien; Delmau, Laetitia Helene

    2014-01-01

    Syntheses for new ligands based upon dibenzothiophene and dibenzothiophene sulfone platforms, decorated with phosphine oxide and methylphosphine oxide donor groups, are described. Coordination chem. of 4, 6- bis(diphenylphosphinoylmethyl) dibenzothiophene (8) , 4, 6- bis(diphenylphosphinoylmethyl) dibenzothiophene- 5, 5- dioxide (9) and 4, 6- bis(diphenylphosphinoyl) dibenzothiophene- 5, 5- dioxide (10) with lanthanide nitrates, Ln(NO3) 3 (H2O) n is outlined, and crystal structure detns. reveal a range of chelation interactions on Ln(III) ions. The HNO3 dependence of the solvent extn. performance of 9 and 10 in 1, 2- dichloroethane for Eu(III) and Am(III) is described and compared against the extn. behavior of related dibenzofuran ligands (2, 3; R = Ph) and n- octyl(phenyl) - N, N- diisobutylcarbamoylmethyl phosphine oxide (4) measured under identical conditions.

  12. Lifetime broadening in the rotationally resolved electronic spectra of dibenzothiophene, 2,5-diphenylfuran, and 2,5-diphenyl-1,3,4-oxadiazole in the gas phase. Intersystem crossing dynamics in the statistical limit.

    PubMed

    Alvarez-Valtierra, Leonardo; Yi, John T; Pratt, David W

    2009-03-19

    The fluorescence lifetime of the zero point vibrational level of the first excited electronic state of dibenzothiophene (DBT) has been determined to be 1.0 ns by analysis of its rotationally resolved S1 <-- S0 fluorescence excitation spectrum. The S1 lifetime of DBT is substantially shorter than those observed for fluorene (FLU), carbazole (CAR), and dibenzofuran (DBF), analogs of DBT in which the heavy sulfur atom is replaced by lighter ones. The electronic origin bands through the series CAR, FLU, DBF, and DBT exhibit a monotonic increase in Lorentzian broadening in their Voigt line shape profiles. Two other heterocyclic molecules manifest similar photophysical properties; 2,5-diphenylfuran and 2,5-diphenyl-1,3,4-oxadiazole. Lorentzian line shape broadenings of approximately 76 MHz were observed in the high-resolution spectra of their origin bands. Possible reasons for the short fluorescence lifetimes of these heterocycles are discussed.

  13. Grafting molecularly imprinted poly(2-acrylamido-2-methylpropanesulfonic acid) onto the surface of carbon microspheres

    NASA Astrophysics Data System (ADS)

    Yang, Yongzhen; Zhang, Yan; Li, Sha; Liu, Xuguang; Xu, Bingshe

    2012-06-01

    Poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS) was grafted on the surface of carbon microspheres (CMSs), which were modified in prior by a mixed acid (HNO3 and H2SO4) oxidation and 3-methacryloxypropyl trimethoxysilane silanization. Then, the molecularly imprinting polymerization was carried out towards the macromolecule PAMPS grafted on the surface of CMSs using dibenzothiophene (DBT) as template, ethylene dimethacrylate as cross-linking agent and (NH4)2S2O8 (APS) as initiator to prepare surface molecularly imprinted polymer (MIP-PAMPS/CMSs) for adsorbing DBT. The optimized conditions of grafting PAMPS, including AMPS dosage, APS content, reaction temperature and reaction time, were emphasized in this paper. The morphology of the samples was characterized by field emission scanning electron microscopy. The functional groups were analyzed qualitatively by Fourier transform infrared spectrometry. The grafting degree of PAMPS was investigated by thermogravimetry. The results show that the preferable AMPS dosage, APS content, reaction temperature and time were 5 g, 0.15 g, 70 °C and 12 h, respectively, for preparing PAMPS/CMSs composite on the basis of 1.0 g of silanized-CMSs. The absorbing characteristic of MIP-PAMPS/CMSs toward DBT was studied preliminarily with dynamic adsorption. In the experiment of dynamic adsorption, MIP-PAMPS/CMSs and non-imprinted polymer (NIP-PAMPS/CMSs) were compared with respect to their rapid adsorption in 1 mmol/L of DBT solution in n-hexane. When the first 1 mL of 1 mmol/L DBT solution was injected and flowed through a column packed with 0.1 g of MIP-PAMPS/CMSs, the content of DBT reduced to 0.265 mmol/L, that is, decreased significantly from 279 to 74 ppm. When 3 mL of DBT solution was flowed through the packed column, the adsorption of MIP-PAMPS/CMSs toward DBT reached saturation with the maximum adsorption amount of 1.38 × 10-2 mmol/g and the overall adsorption efficiency of 46%, while NIP-PAMPS/CMSs adsorbed only 1.66

  14. Microbial Desulfurization of Alkylated Dibenzothiophenes from a Hydrodesulfurized Middle Distillate by Rhodococcus erythropolis I-19

    PubMed Central

    Folsom, B. R.; Schieche, D. R.; DiGrazia, P. M.; Werner, J.; Palmer, S.

    1999-01-01

    Rhodococcus erythropolis I-19, containing multiple copies of key dsz genes, was used to desulfurize alkylated dibenzothiophenes (Cx-DBTs) found in a hydrodesulfurized middle-distillate petroleum (MD 1850). Initial desulfurization rates of dibenzothiophene (DBT) and MD 1850 by I-19 were 5.0 and 2.5 μmol g dry cell weight−1 min−1, more than 25-fold higher than that for wild-type bacteria. According to sulfur K-edge X-ray absorption near-edge structure (XANES) analysis, thiophenic compounds accounted for >95% of the total sulfur found in MD 1850, predominantly Cx-DBTs and alkylated benzothiophenes. Extensive biodesulfurization resulted in a 67% reduction of total sulfur from 1,850 to 615 ppm S. XANES analysis of the 615-ppm material gave a sulfur distribution of 75% thiophenes, 11% sulfides, 2% sulfoxides, and 12% sulfones. I-19 preferentially desulfurized DBT and C1-DBTs, followed by the more highly alkylated Cx-DBTs. Shifting zero- to first-order (first-order) desulfurization rate kinetics were observed when MD 1850 was diluted with hexadecane. Apparent saturation rate constant (K0) and half-saturation rate constant (K1) values were calculated to be 2.8 μmol g dry cell weight−1 min−1 and 130 ppm, respectively. However, partial biocatalytic reduction of MD 1850 sulfur concentration followed by determination of initial rates with fresh biocatalyst led to a sigmoidal kinetic behavior. A competitive-substrate model suggested that the apparent K1 values for each group of Cx-DBTs increased with increasing alkylation. Overall desulfurization rate kinetics with I-19 were affected by the concentration and distribution of Cx-DBTs according to the number and/or lengths of alkyl groups attached to the basic ring structure. PMID:10543810

  15. Transition Metal Complexes of Cr, Mo, W and Mn Containing η1(S)-2,5-Dimethylthiophene, Benzothiophene and Dibenzothiophene Ligands

    SciTech Connect

    Reynolds, Michael

    2000-09-21

    The UV photolysis of hexanes solutions containing the complexes M(CO)6 (M=Cr, Mo, W) or CpMn(CO)3 (Cp=η5-C5H5) and excess thiophene (T*) (T*=2,5-dimethylthiophene (2,5-Me2T), benzothiophene (BT), and dibenzothiophene (DBT)) produces the η1(S)-T* complexes (CO)5M(η1(S)-T*) 1-8 or Cp(CO)2Mn(η1(S)-T*)9-11, respectively. However, when T*=DBT, and M=Mo, a mixture of two products result which includes the η1(S)-DBT complex (CO)5Mo(η1(S)-DBT) 4a and the unexpected π-complex (CO)3Mo(η{sup 6}-DBT) 4b as detected by 1H NMR. The liability of the η1(S)-T* ligands is illustrated by the rapid displacement of DBT in the complex (CO)5W(η1(S)-DBT) (1) by THF, and also in the complexes (CO)5Cr(η1(S)-DBT) (5) and CpMn(CO)21(S)-DBT) (9) by CO (1 atm) at room temperature. Complexes 1-11 have been characterized spectroscopically (1H NMR, IR) and when possible isolated as analytically pure solids (elemental analysis, EIMS). Single crystal, X-ray structural determinations are reported for (Cη)5W(η1(S)-DBT) and Cp(CO)2Mn(η1(S)-DBT).

  16. Therapists' Use of DBT: A Survey Study of Clinical Practice

    ERIC Educational Resources Information Center

    DiGiorgio, Kimberly E.; Glass, Carol R.; Arnkoff, Diane B.

    2010-01-01

    The purpose of this study was to examine how therapists conduct Dialectical Behavior Therapy (DBT) individual psychotherapy with clients, focusing on clinical factors that could account for decisions regarding modifications of DBT (e.g., client diagnosis, therapist theoretical orientation, and intensity of DBT training). Additionally, the study…

  17. DBT — EDRN Public Portal

    Cancer.gov

    From NCBI Gene: The branched-chain alpha-keto acid dehydrogenase complex (BCKD) is an inner-mitochondrial enzyme complex involved in the breakdown of the branched-chain amino acids isoleucine, leucine, and valine. The BCKD complex is thought to be composed of a core of 24 transacylase (E2) subunits, and associated decarboxylase (E1), dehydrogenase (E3), and regulatory subunits. This gene encodes the transacylase (E2) subunit. Mutations in this gene result in maple syrup urine disease, type 2. Alternatively spliced transcript variants have been described, but their biological validity has not been determined. [provided by RefSeq, Jul 2008

  18. Biodesulfurization of dibenzothiophene and crude oil using electro-spray reactors

    SciTech Connect

    Kaufman, E.N.; Harkins, J.B.; Rodriguez, M.; Tsouris, C.; Selvaraj, P.T.

    1996-10-01

    Biological removal of organic sulfur from petroleum feedstocks offers an attractive alternative to conventional thermochemical treatment due to the mild operating conditions afforded by the biocatalyst. In order for biodesulfurization to realize commercial success, reactors must be designed which allow for sufficient liquid / liquid and gas / liquid mass transfer while simultaneously reducing operating costs. In this study, the use of electric field contactors for the biodesulfurization of the model compound dibenzothiophene (DBT) as well as actual crude oil is investigated. The emulsion phase contactor (EPC) creates an emulsion of aqueous biocatalyst in the organic phase by concentrating forces at the liquid / liquid interface rather than imparting energy to the bulk solution as is done in impeller-based reactors. Characterization of emulsion quality and determination of rates of DBT oxidation to 2- hydroxybiphenyl (2-HBP) were performed for both batch stirred reactors (BSR) and the EPC. The EPC was capable of producing aqueous droplets of about 5 {micro}m in diameter using 3 W/L whereas the impeller-based reactor formed droplets between 100 and 200 {micro}m with comparable power consumption. The presence of electric fields was not found to adversely affect biocatalytic activity. Despite the greater surface area for reaction afforded by the EPC, rates of DBT oxidation in both reactors were similar, demonstrating that the biocatalyst used (Rhodococcus sp. IGTS8) was not active enough to be mass transport limited. The EPC is expected to have tremendous impact upon reactor operating costs and biocatalyst utilization once advances biocatalyst development provide systems that are mass transport limited.

  19. Biodegradation and adsorption of C1- and C2-phenanthrenes and C1- and C2-dibenzothiophenes in the presence of clay minerals: effect on forensic diagnostic ratios.

    PubMed

    Ugochukwu, Uzochukwu C; Head, Ian M; Manning, David A C

    2014-07-01

    The impact of modified montmorillonites on adsorption and biodegradation of crude oil C1-phenanthrenes, C1-dibenzothiophenes, C2-phenanthrenes and C2-dibenzothiophenes was investigated in aqueous clay/oil microcosm experiments with a hydrocarbon degrading microorganism community. Consequently, the effect on C1-dibenzothiophenes/C1-phenanthrenes, C2-dibenzothiophenes/C2-phenanthrenes, 2+3-methyldibenzothiophene/4-methyldibenzothiophene and 1-methyldibenzothiophene/4-methyldibenzothiophene ratios commonly used as diagnostic ratios for oil forensic studies was evaluated. The clay mineral samples were treated to produce acid activated montmorillonite, organomontmorillonite and homoionic montmorillonite which were used in this study. The different clay minerals (modified and unmodified) showed varied degrees of biodegradation and adsorption of the C1-phenanthrenes, C1-dibenzothiophenes, C2-phenanthrenes and C2-dibenzothiophenes. The study indicated that as opposed to biodegradation, adsorption has no effect on the diagnostic ratios. Among the diagnostic ratios reviewed, only C2-dibenzothiophenes/C2-phenanthrenes ratio was neither affected by adsorption nor biodegradation making this ratio very useful in forensic studies of oil spills and oil-oil correlation.

  20. Identification and Cloning of Genes Involved in Specific Desulfurization of Dibenzothiophene by Rhodococcus sp. Strain IGTS8.

    PubMed

    Denome, S A; Olson, E S; Young, K D

    1993-09-01

    The gram-positive bacterium Rhodococcus sp. strain IGTS8 is able to remove sulfur from certain aromatic compounds without breaking carbon-carbon bonds. In particular, sulfur is removed from dibenzothiophene (DBT) to give the final product, 2-hydroxybiphenyl. A genomic library of IGTS8 was constructed in the cosmid vector pLAFR5, but no desulfurization phenotype was imparted to Escherichia coli. Therefore, IGTS8 was mutagenized, and a new strain (UV1) was selected that had lost the ability to desulfurize DBT. The genomic library was transferred into UV1, and several colonies that had regained the desulfurization phenotype were isolated, though free plasmid could not be isolated. Instead, vector DNA had integrated into either the chromosome or a large resident plasmid. DNA on either side of the inserted vector sequences was cloned and used to probe the original genomic library in E. coli. This procedure identified individual cosmid clones that, when electroporated into strain UV1, restored desulfurization. When the origin of replication from a Rhodococcus plasmid was inserted, the efficiency with which these clones transformed UV1 increased 20- to 50-fold and they could be retrieved as free plasmids. Restriction mapping and subcloning indicated that the desulfurization genes reside on a 4.0-kb DNA fragment. Finally, the phenotype was transferred to Rhodococcus fascians D188-5, a species normally incapable of desulfurizing DBT. The mutant strain, UV1, and R. fascians produced 2-hydroxybiphenyl from DBT when they contained appropriate clones, indicating that the genes for the entire pathway have been isolated.

  1. Sulfur-selective desulfurization of dibenzothiophene and diesel oil by newly isolated Rhodococcus sp. strains.

    PubMed

    Castorena, Gladys; Suárez, Claudia; Valdez, Idania; Amador, Guadalupe; Fernández, Luis; Le Borgne, Sylvie

    2002-09-24

    New desulfurizing bacteria able to convert dibenzothiophene into 2-hydroxybiphenyl and sulfate were isolated from contaminated soils collected in Mexican refineries. Random amplified polymorphic DNA analysis showed they were different from previously reported Rhodococcus erythropolis desulfurizing strains. According to 16S rRNA gene sequencing and fatty acid analyses, these new isolates belonged to the genus Rhodococcus. These strains could desulfurize 4,6-dimethyldibenzothiophene which is one of the most difficult dibenzothiophene derivatives to remove by hydrodesulfurization. A deeply hydrodesulfurized diesel oil containing significant amounts of 4,6-dimethyldibenzothiophene was treated with Rhodococcus sp. IMP-S02 cells. Up to 60% of the total sulfur was removed and all the 4,6-dimethyldibenzothiophene disappeared as a result of this treatment.

  2. Characterization of Gordonia sp. strain F.5.25.8 capable of dibenzothiophene desulfurization and carbazole utilization.

    PubMed

    Santos, S C C; Alviano, D S; Alviano, C S; Pádula, M; Leitão, A C; Martins, O B; Ribeiro, C M S; Sassaki, M Y M; Matta, C P S; Bevilaqua, J; Sebastián, G V; Seldin, L

    2006-07-01

    A dibenzothiophene (DBT)-degrading bacterial strain able to utilize carbazole as the only source of nitrogen was identified as Gordonia sp. F.5.25.8 due to its 16S rRNA gene sequence and phenotypic characteristics. Gas chromatography (GC) and GC-mass spectroscopy analyses showed that strain F.5.25.8 transformed DBT into 2-hydroxybiphenyl (2-HBP). This strain was also able to grow using various organic sulfur or nitrogen compounds as the sole sulfur or nitrogen sources. Resting-cell studies indicated that desulfurization occurs either in cell-associated or in cell-free extracts of F.5.25.8. The biological responses of F.5.25.8 to a series of mutagens and environmental agents were also characterized. The results revealed that this strain is highly tolerant to DNA damage and also refractory to induced mutagenesis. Strain F.5.25.8 was also characterized genetically. Results showed that genes involved in desulfurization (dsz) are located in the chromosome, and PCR amplification was observed with primers dszA and dszB designed based on Rhodococcus genes. However, no amplification product was observed with the primer based on dszC.

  3. Influence of DBT reconstruction algorithm on power law spectrum coefficient

    NASA Astrophysics Data System (ADS)

    Vancamberg, Laurence; Carton, Ann-Katherine; Abderrahmane, Ilyes H.; Palma, Giovanni; Milioni de Carvalho, Pablo; Iordache, Rǎzvan; Muller, Serge

    2015-03-01

    In breast X-ray images, texture has been characterized by a noise power spectrum (NPS) that has an inverse power-law shape described by its slope β in the log-log domain. It has been suggested that the magnitude of the power-law spectrum coefficient β is related to mass lesion detection performance. We assessed β in reconstructed digital breast tomosynthesis (DBT) images to evaluate its sensitivity to different typical reconstruction algorithms including simple back projection (SBP), filtered back projection (FBP) and a simultaneous iterative reconstruction algorithm (SIRT 30 iterations). Results were further compared to the β coefficient estimated from 2D central DBT projections. The calculations were performed on 31 unilateral clinical DBT data sets and simulated DBT images from 31 anthropomorphic software breast phantoms. Our results show that β highly depends on the reconstruction algorithm; the highest β values were found for SBP, followed by reconstruction with FBP, while the lowest β values were found for SIRT. In contrast to previous studies, we found that β is not always lower in reconstructed DBT slices, compared to 2D projections and this depends on the reconstruction algorithm. All β values estimated in DBT slices reconstructed with SBP were larger than β values from 2D central projections. Our study also shows that the reconstruction algorithm affects the symmetry of the breast texture NPS; the NPS of clinical cases reconstructed with SBP exhibit the highest symmetry, while the NPS of cases reconstructed with SIRT exhibit the highest asymmetry.

  4. In situ synthesis, characterization, and catalytic performance of tungstophosphoric acid encapsulated into the framework of mesoporous silica pillared clay.

    PubMed

    Li, Baoshan; Liu, Zhenxing; Han, Chunying; Ma, Wei; Zhao, Songjie

    2012-07-01

    Mesoporous silica pillared clay (SPC) incorporated with tungstophosphoric acid (HPW) has been synthesized via in situ introducing P and W source in the acidic suspension of the clay interlayer template during the formation of the silica pillared clay. The samples were characterized by XRD, XRF, FT-IR, TG-DTA, N(2) adsorption-desorption, and SEM techniques. The results showed that the HPW formed by in situ method has been effectively introduced into the framework of mesoporous silica pillared clay and its Keggin structure remained perfectly after formation of the materials. In addition, samples with similar HPW loadings were also prepared by impregnation method using SPC as the support. HPW in the incorporated samples was better dispersed into the silica pillared clay than in the impregnated samples. The results of catalytic tests indicated that the encapsulated materials demonstrated better catalytic performance than the impregnated samples in oxidative desulfurization (ODS) of dibenzothiophene (DBT).

  5. A luminescent Eu(III) complex based on 2-(4', 4', 4'-trifluoro-1', 3'-dioxobutyl)-dibenzothiophene for light-emitting diodes

    NASA Astrophysics Data System (ADS)

    Liu, Sheng-Gui; Gong, Meng-Lian; Wang, Sheng; Tan, Xiu-Mei

    2009-10-01

    Complex Eu(dbt) 3(phen) (Hdbt = 2-(4', 4', 4'-trifluoro-1', 3'-dioxobutyl)-dibenzothiophene, phen = 1,10-phenanthroline) was synthesized. The complex emits red luminescence, characteristic of the 5D0 → 7FJ ( J = 0-4) emission bands of Eu 3+ under near ultraviolet. A red conversion light-emitting diode (LED) device was fabricated by coating complex onto InGaN-based-LED chip that emits 395 nm ultraviolet light. When the mass ratio of the red phosphor to the silicone is 1:25, the LED device's CIE chromaticity coordinates are x = 0.5835, y = 0.2857, and the luminescence efficiency is 1.29 lm/w. All the results show that this europium complex may act as a red component in fabrication of white LEDs with high color-rendering index.

  6. A luminescent Eu(III) complex based on 2-(4', 4', 4'-trifluoro-1', 3'-dioxobutyl)-dibenzothiophene for light-emitting diodes.

    PubMed

    Liu, Sheng-Gui; Gong, Meng-Lian; Wang, Sheng; Tan, Xiu-Mei

    2009-10-15

    Complex Eu(dbt)(3)(phen) (Hdbt=2-(4', 4', 4'-trifluoro-1', 3'-dioxobutyl)-dibenzothiophene, phen=1,10-phenanthroline) was synthesized. The complex emits red luminescence, characteristic of the (5)D(0)-->(7)F(J) (J=0-4) emission bands of Eu(3+) under near ultraviolet. A red conversion light-emitting diode (LED) device was fabricated by coating complex onto InGaN-based-LED chip that emits 395nm ultraviolet light. When the mass ratio of the red phosphor to the silicone is 1:25, the LED device's CIE chromaticity coordinates are x=0.5835, y=0.2857, and the luminescence efficiency is 1.29 lm/w. All the results show that this europium complex may act as a red component in fabrication of white LEDs with high color-rendering index.

  7. PFO-DBT:MEH-PPV:PC71BM Ternary Blend Assisted Platform as a Photodetector

    PubMed Central

    Zafar, Qayyum; Ahmad, Zubair; Sulaiman, Khaulah

    2015-01-01

    We present a ternary blend-based bulk heterojunction ITO/PEDOT:PSS/PFO-DBT:MEH-PPV:PC71BM/LiF/Al photodetector. Enhanced optical absorption range of the active film has been achieved by blending two donor components viz. poly[2,7-(9,9-di-octyl-fluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) and poly(2-methoxy-5(2′-ethylhexyloxy) phenylenevinylene (MEH-PPV) along with an acceptor component, i.e., (6,6)-phenyl-C71 hexnoic acid methyl ester. The dependency of the generation rate of free charge carriers in the organic photodetector (OPD) on varied incident optical power density was investigated as a function of different reverse biasing voltages. The photocurrent showed significant enhancement as the intensity of light impinging on active area of OPD is increased. The ratio of Ilight to Idark of fabricated device at −3 V was ∼3.5 × 104. The dynamic behaviour of the OPD under on/off switching irradiation revealed that sensor exhibits quick response and recovery time of <800 ms and 500 ms, respectively. Besides reliability and repeatability in the photoresponse characteristics, the cost-effective and eco-friendly fabrication is the added benefit of the fabricated OPD. PMID:25574936

  8. Piloting a Dialectical Behavioral Therapy (DBT) Infused Skills Group in a Disciplinary Alternative Education Program (DAEP)

    ERIC Educational Resources Information Center

    Ricard, Richard J.; Lerma, Eunice; Heard, Courtney C. C.

    2013-01-01

    This study explored the impact of a 4-week skills group intervention based on the principles of Dialectical Behavior Therapy (DBT) with a sample of adolescents attending a Disciplinary Alternative Education Program. This article provides a session-by-session overview of activities adapted from DBT-specified training modules of mindfulness,…

  9. Comparison of computerized mass detection in digital breast tomosynthesis (DBT) mammograms and conventional mammograms

    NASA Astrophysics Data System (ADS)

    Chan, Heang-Ping; Wei, Jun; Sahiner, Berkman; Hadjiiski, Lubomir; Helvie, Mark A.

    2009-02-01

    We are developing a CAD system for mass detection on digital breast tomosynthesis (DBT) mammograms. In this study, we compared the detection accuracy on DBT and conventional screen-film mammograms (SFMs). DBT mammograms were acquired with a GE prototype system at the University of Michigan. 47 cases containing the CC- and MLO-view DBT mammograms of the breast with a biopsy-proven mass and the corresponding two-view SFMs of the same breast were collected. Subjective judgment showed that the masses were much more conspicuous on DBT slices than on SFMs. The CAD system for DBT includes two parallel processes, one performs mass detection in the reconstructed DBT volume, and the other in the projection view (PV) images. The mass likelihood scores estimated for each mass candidate in the two processes are merged to differentiate masses and false positives (FPs). For detection on SFMs, we previously developed a dual system approach by fusing two single CAD systems optimized for detection of average and subtle masses, respectively. A trained neural network is used to merge the mass likelihood scores of the two single systems to reduce FPs. At the case-based sensitivities of 80% and 85%, mass detection in the DBT volume resulted in an average of 0.72 and 1.06 FPs/view, and detection in the SFMs yielded 0.94 and 1.67 FPs/view, respectively. The difference fell short of statistical significance (p=0.07) by JAFROC analysis. Study is underway to collect a larger data set and to further improve the DBT CAD system.

  10. Desulfurization of 4-methyl dibenzothiophene using titanium supported Keggin type polyoxometalate

    NASA Astrophysics Data System (ADS)

    Lesbani, Aldes; Anggraini, Ana; Mohadi, Risfidian; Rohendi, Dedi; Said, Muhammad

    2017-03-01

    Titanium supported Keggin type polyoxometalate H5PV2Mo10O40.nH2O has been prepared using tetra isopropyl orthotitanate by sol-gel method and microemulsion to form H5PV2Mo10O40/TiO2. Compound H5PV2Mo10O40.nH2O/TiO2 was characterized using FTTR spectroscopy, X-Ray analysis, and acidity measurement. FTTR spectrum showed that all vibration of titanium and polyoxometalate were appeared in H5PV2Mo10O40.nH2O/TiO2 with decreasing crystallinity. The acidity of H5PV2Mo10O40.nH2O/TiO2 was higher than H5PV2Mo10O40.nH2O. Desulfurization of 4-methyl dibenzothiophene (4-MDBT) using H5PV2Mo10O40.nH2O/TiO2 as catalyst resulted conversion of 4-MDBT was 99% and higher than desulfurization using H5PV2Mo10O40.nH2O under mild conditions.

  11. Sources of polychlorinated dibenzothiophenes in Newark Bay estuary sediments

    SciTech Connect

    Huntley, S.L.; Wenning, R.J.; Paustenbach, D.J.; Wong, A.S.; Luksemburg, W.J.

    1994-12-31

    Polychlorinated dibenzothiophenes (PCDTS) are sulfur-containing structural analogs of polychlorinated dibenzofurans (PCDFs). Research to date indicates that PCDTs are formed by mechanisms similar to those that result in the formation of PCDFs and polychlorinated dibenzo-p-dioxins (PCDDs). PCDTs have been detected in fly ash from municipal incinerators and effluent from pulp and paper mills. Under laboratory conditions, PCDTs have been formed by thermal reaction of polychlorinated biphenyls and polychlorinated benzenes in the presence of elemental sulfur. The available data on sources of PCDTs suggests that environmental contamination is likely to be widespread. Recently, six samples collected from the lower Passaic River were reported to have a mean concentration of 3,680 ppt 2,4,6,8-tetrachlorodibenzothiophene. It has been suggested that this compound is a chemical marker for 2,4,5-trichlorophenol production. Such a relationship, however, has not been demonstrated. Several pulp and paper mills on the Passaic River, numerous municipal and industrial incinerators, manufacturers of sulfur-containing pesticides, and a nearby PCB-contaminated site are possible sources of PCDTs in the Newark Bay estuary. This study reports on the results of recent investigations to characterize the sources of 2,4,6,8-PCDT in the estuary.

  12. Adaptive diffusion regularization for enhancement of microcalcifications in digital breast tomosynthesis (DBT) reconstruction

    NASA Astrophysics Data System (ADS)

    Lu, Yao; Chan, Heang-Ping; Fessler, Jeffrey A.; Hadjiiski, Lubomir; Wei, Jun; Goodsitt, Mitchell M.

    2011-03-01

    Digital breast tomosynthesis (DBT) has been shown to increase mass detection. Detection of microcalcifications in DBT is challenging because of the small, subtle signals to be searched in the large breast volume and the noise in the reconstructed volume. We developed an adaptive diffusion (AD) regularization method that can differentially regularize noise and potential signal regions during reconstruction based on local contrast-to-noise ratio (CNR) information. This method adaptively applies different degrees of regularity to signal and noise regions, as guided by a CNR map for each DBT slice within the image volume, such that potential signals will be preserved while noise is suppressed. DBT scans of an American College of Radiology phantom and the breast of a subject with biopsy-proven calcifications were acquired with a GE prototype DBT system at 21 angles in 3° increments over a +/-30° range. Simultaneous algebraic reconstruction technique (SART) was used for DBT reconstruction. The AD regularization method was compared to the non-convex total p-variation (TpV) method and SART with no regularization (NR) in terms of the CNR and the full width at half maximum (FWHM) of the central gray-level line profile in the focal plane of a calcification. The results demonstrated that the SART regularized by the AD method enhanced the CNR and preserved the sharpness of microcalcifications compared to reconstruction without regularization. The AD regularization was superior to the TpV method for subtle microcalcifications in terms of the CNR while the FWHM was comparable. The AD regularized reconstruction has the potential to improve the CNR of microcalcifications in DBT for human or machine detection.

  13. Organotins (TBT and DBT) in water, sediments, and gastropods of the southern Venice lagoon (Italy).

    PubMed

    Berto, D; Giani, M; Boscolo, R; Covelli, S; Giovanardi, O; Massironi, M; Grassia, L

    2007-01-01

    The release of tributyltin (TBT) from maritime traffic represents one of the main problems of direct, diffuse, and continued contamination of the marine environment. In the present survey, the concentrations of TBT and dibultytin (DBT) in brackish waters, sediments, and the gastropods Nassarius nitidus were evaluated in order to estimate the contamination of the southern part of the Venice lagoon. TBT and DBT were determined by GC-MS/MS. Recent contamination of TBT was found in brackish waters near marinas, whereas the highest concentrations of TBT and DBT were observed in surface sediments at dockyards and harbours. High content of organotin in the gastropods sampled near the dockyards, harbours, and marinas showed a mobilisation from the sediments through the food web. The present study allowed assessment of whether, despite the ban on the use of TBT paints, waters, sediments, and biota were still being contaminated by organotin compounds in the southern Venice lagoon.

  14. Dialectical Behavior Therapy (DBT) Applied to College Students: A Randomized Clinical Trial

    PubMed Central

    Pistorello, Jacqueline; Fruzzetti, Alan E.; MacLane, Chelsea; Gallop, Robert; Iverson, Katherine M.

    2012-01-01

    Objective College counseling centers (CCCs) are increasingly being called upon to treat highly distressed students with complex clinical presentations. This study compared the effectiveness of Dialectical Behavior Therapy (DBT) for suicidal college students to an optimized control condition, and analyzed baseline global functioning as a moderator. Method The intent-to-treat (ITT) sample included 63 college students between the ages of 18 and 25 who were suicidal at baseline, reported at least one lifetime non-suicidal self-injurious (NSSI) act or suicide attempt, and met three or more borderline personality disorder (BPD) diagnostic criteria. Participants were randomly assigned to DBT (n = 31) or an optimized Treatment as Usual (O-TAU) control condition (n = 32). Treatment was provided by trainees, supervised by experts in both treatments. Both treatments lasted 7–12 months and included both individual and group components. Assessments were conducted at pretreatment, 3-months, 6-months, 9-months, 12-months, and 18-months (follow-up). Results Mixed effects analyses (ITT sample) revealed that DBT, compared to the control condition, showed significantly greater decreases in suicidality, depression, number of NSSI events (if participant had self-injured), BPD criteria, and psychotropic medication use, and significantly greater improvements in social adjustment. Most of these treatment effects were observed at follow-up. No treatment differences were found for treatment dropout. Moderation analyses showed that DBT was particularly effective for suicidal students who were lower functioning at pretreatment. Conclusions DBT is an effective treatment for suicidal, multi-problem college students. Future research should examine the implementation of DBT in CCCs in a stepped care approach. PMID:22730955

  15. High dynamic range CMOS-based mammography detector for FFDM and DBT

    NASA Astrophysics Data System (ADS)

    Peters, Inge M.; Smit, Chiel; Miller, James J.; Lomako, Andrey

    2016-03-01

    Digital Breast Tomosynthesis (DBT) requires excellent image quality in a dynamic mode at very low dose levels while Full Field Digital Mammography (FFDM) is a static imaging modality that requires high saturation dose levels. These opposing requirements can only be met by a dynamic detector with a high dynamic range. This paper will discuss a wafer-scale CMOS-based mammography detector with 49.5 μm pixels and a CsI scintillator. Excellent image quality is obtained for FFDM as well as DBT applications, comparing favorably with a-Se detectors that dominate the X-ray mammography market today. The typical dynamic range of a mammography detector is not high enough to accommodate both the low noise and the high saturation dose requirements for DBT and FFDM applications, respectively. An approach based on gain switching does not provide the signal-to-noise benefits in the low-dose DBT conditions. The solution to this is to add frame summing functionality to the detector. In one X-ray pulse several image frames will be acquired and summed. The requirements to implement this into a detector are low noise levels, high frame rates and low lag performance, all of which are unique characteristics of CMOS detectors. Results are presented to prove that excellent image quality is achieved, using a single detector for both DBT as well as FFDM dose conditions. This method of frame summing gave the opportunity to optimize the detector noise and saturation level for DBT applications, to achieve high DQE level at low dose, without compromising the FFDM performance.

  16. Implementation of DBT-Informed Therapy at a Rural University Training Clinic: A Case Study

    ERIC Educational Resources Information Center

    Kerr, Patrick L.; Muehlenkamp, Jennifer J.; Larsen, Margo Adams

    2009-01-01

    University training clinics offer state-of-the-art treatment opportunities for clients, particularly for underserved and underinsured client populations. Little has been published regarding the implementation of Dialectical Behavior Therapy (DBT) in settings such as a university training clinic, which may face challenges in utilizing such a…

  17. Utilizing DBT Skills to Augment Traditional CBT for Trichotillomania: An Adult Case Study

    ERIC Educational Resources Information Center

    Keuthen, Nancy J.; Sprich, Susan E.

    2012-01-01

    Traditional cognitive-behavioral interventions for trichotillomania have had modest acute treatment outcomes and poor maintenance of gains over time. Techniques adopted from dialectical behavior therapy (DBT) can potentially enhance treatment outcomes by specifically addressing issues of impulsivity, emotion regulation, and distress tolerance. In…

  18. Dialectical Behavior Therapy (DBT) Applied to College Students: A Randomized Clinical Trial

    ERIC Educational Resources Information Center

    Pistorello, Jacqueline; Fruzzetti, Alan E.; MacLane, Chelsea; Gallop, Robert; Iverson, Katherine M.

    2012-01-01

    Objective: College counseling centers (CCCs) are increasingly being called upon to treat highly distressed students with complex clinical presentations. This study compared the effectiveness of Dialectical Behavior Therapy (DBT) for suicidal college students with an optimized control condition and analyzed baseline global functioning as a…

  19. Optimization of digital breast tomosynthesis (DBT) acquisition parameters for human observers: effect of reconstruction algorithms.

    PubMed

    Zeng, Rongping; Badano, Aldo; Myers, Kyle

    2017-02-02

    We showed in our earlier work that the choice of reconstruction methods does not affect the optimization of DBT acquisition parameters (angular span and number of views) using simulated breast phantom images in detecting lesions with a channelized Hoteling observer (CHO). In this work we investigate whether the model-observer based conclusion is valid when using humans to interpret images. We used previously generated DBT breast phantom images and recruited human readers to find the optimal geometry settings associated with two reconstruction algorithms, filtered back projection (FBP) and simultaneous algebraic reconstruction technique (SART). The human reader results show that image quality trends as a function of the acquisition parameters are consistent between FBP and SART reconstructions. The consistent trends confirm that the optimization of DBT system geometry is insensitive to the choice of reconstruction algorithm. The results also show that humans perform better in SART reconstructed images than in FBP reconstructed images. In addition, we applied CHOs with three commonly used channel models, Laguerre-Gauss (LG) channels, square (SQR) channels and sparse difference-of-Gaussian (sDOG) channels. We found that LG channels predict human performance trends better than SQR and sDOG channel models for the task of detecting lesions in tomosynthesis backgrounds. Overall, this work confirms that the choice of reconstruction algorithm is not critical for optimizing DBT system acquisition parameters.

  20. Optimization of digital breast tomosynthesis (DBT) acquisition parameters for human observers: effect of reconstruction algorithms

    NASA Astrophysics Data System (ADS)

    Zeng, Rongping; Badano, Aldo; Myers, Kyle J.

    2017-04-01

    We showed in our earlier work that the choice of reconstruction methods does not affect the optimization of DBT acquisition parameters (angular span and number of views) using simulated breast phantom images in detecting lesions with a channelized Hotelling observer (CHO). In this work we investigate whether the model-observer based conclusion is valid when using humans to interpret images. We used previously generated DBT breast phantom images and recruited human readers to find the optimal geometry settings associated with two reconstruction algorithms, filtered back projection (FBP) and simultaneous algebraic reconstruction technique (SART). The human reader results show that image quality trends as a function of the acquisition parameters are consistent between FBP and SART reconstructions. The consistent trends confirm that the optimization of DBT system geometry is insensitive to the choice of reconstruction algorithm. The results also show that humans perform better in SART reconstructed images than in FBP reconstructed images. In addition, we applied CHOs with three commonly used channel models, Laguerre–Gauss (LG) channels, square (SQR) channels and sparse difference-of-Gaussian (sDOG) channels. We found that LG channels predict human performance trends better than SQR and sDOG channel models for the task of detecting lesions in tomosynthesis backgrounds. Overall, this work confirms that the choice of reconstruction algorithm is not critical for optimizing DBT system acquisition parameters.

  1. Meta-Analysis and Systematic Review Assessing the Efficacy of Dialectical Behavior Therapy (DBT)

    ERIC Educational Resources Information Center

    Panos, Patrick T.; Jackson, John W.; Hasan, Omar; Panos, Angelea

    2014-01-01

    Objective: The objective was to quantitatively and qualitatively examine the efficacy of DBT (e.g., decreasing life-threatening suicidal and parasuicidal acts, attrition, and depression) explicitly with borderline personality disorder (BPD) and using conservative assumptions and criteria, across treatment providers and settings. Method: Five…

  2. Orienting Adolescents and Families to DBT Telephone Consultation: Principles, Procedures, and Pitfalls

    ERIC Educational Resources Information Center

    Steinberg, Jennifer A.; Steinberg, Sara J.; Miller, Alec L.

    2011-01-01

    Preliminary studies evaluating dialectical behavior therapy with adolescents have obtained promising outcomes. This multimodal therapy includes telephone consultation for adolescents and for their family members to help ensure generalization of skills from the therapy office to their natural environments. Telephone contact with the DBT therapist…

  3. Benzo[b]naphthothiophenes and alkyl dibenzothiophenes: molecular tracers for oil migration distances

    USGS Publications Warehouse

    Li, Meijun; Wang, T.-G.; Shi, Shengbao; Liu, Keyu; Ellis, Geoffrey S.

    2014-01-01

    The secondary migration of petroleum is one of the most critical geological processes responsible for the accumulation of hydrocarbons in a sedimentary basin. Pyrrolic nitrogen compounds such as carbazoles and benzocarbazoles are thought to be practical molecular indicators for estimating relative migration distances of oil. In light oils or condensates, however, considerable analytical errors are usually caused by low concentrations of NSO-compounds. Here we show that polycyclic sulfur aromatic hydrocarbons such as dibenzothiophene, C1∼C3 alkylated dibenzothiophenes and benzo[b]naphthothiophenes, which are present in relatively higher concentrations than the pyrrolic nitrogen compounds, exhibit changes in both absolute and relative concentrations that correlate with migration distances. The polycyclic sulfur aromatic hydrocarbons related parameters — benzo[b]naphtho[2,1-d]thiophene/{benzo[b]naphtho[2,1-d]thiophene + benzo[b]naphtho[1,2-d]thiophene} (abbreviated as [2,1]BNT/([2,1]BNT+[1,2]BNT) and the concentration of total dibenzothiophenes plus benzo[b]naphthothiophenes — are proposed by this paper to trace the oil migration distances.

  4. Assessment of adsorption behavior of dibutyltin (DBT) to clay-rich sediments in comparison to the highly toxic tributyltin (TBT).

    PubMed

    Hoch, Marion; Alonso-Azcarate, Jacinto; Lischick, Martin

    2003-01-01

    The sorption behavior of dibutyltin (DBT) to four types of natural clay-rich sediments as a function of pH and salinity was studied. The strongest affinity of DBT was found to the montmorillonite-rich sediment, which is characterized by the highest specific surface area and cation exchange capacity of the four used sediments. Kd values range between 12 and 40 (l/kg) on simulated marine conditions (pH 8, salinity 32%). A maximum of DBT adsorption was found at a salinity of 0% and pH 6. Desorption occurred over the entire studied pH range (4-8) when contaminated sediments interact with butyltin-free water. The maximum of desorption coincided with the minimum of adsorption, and vice versa. The results of DBT adsorption are compared with tributyltin (TBT), and the mechanism of the adsorption process is discussed.

  5. Tributyltin (TBT) and dibutyltin (DBT) differently inhibit the mitochondrial Mg-ATPase activity in mussel digestive gland.

    PubMed

    Nesci, Salvatore; Ventrella, Vittoria; Trombetti, Fabiana; Pirini, Maurizio; Borgatti, Anna Rosa; Pagliarani, Alessandra

    2011-02-01

    Tri-n-butyltin (TBT) has long been considered as the most toxic among organotins, especially to membrane systems. The partially dealkylated derivative di-n-butyltin (DBT) has up to now received poor attention and, whenever considered, shown to be less toxic than TBT except on the immune system. The present kinetic approach evidences that both TBT and DBT in vitro inhibit the Mg-ATPase in mussel digestive gland mitochondria by a different mechanism. DBT even displays a higher efficiency than TBT (IC(50)=0.32 μM for TBT vs. 0.19 μM for DBT) in inhibiting the enzyme hydrolytic activity. Differently from TBT which at high concentrations (>1 μM) apparently decreases the oligomycin-sensitivity of the Mg-ATPase, DBT at any concentration tested does not affect the oligomycin sensitivity. TBT probably binds to F(0), either in the form of free enzyme or of enzyme-substrate complex (Ki=K'i), acting as non-competitive inhibitor with respect to the ATP substrate. Conversely DBT, which acts as uncompetitive inhibitor of ATP and as competitive inhibitor of Mg(2+) cofactor, may bind strongly to F(1) subunit, thus preventing ATP hydrolysis. The Mg-ATPase inhibition by both organotins warns against a potential threat to crucial cell energy metabolism processes even after years from contamination and partial TBT debutylation.

  6. Comparison of model and human observer performance in FFDM, DBT, and synthetic mammography

    NASA Astrophysics Data System (ADS)

    Ikejimba, Lynda; Glick, Stephen J.; Samei, Ehsan; Lo, Joseph Y.

    2016-03-01

    Reader studies are important in assessing breast imaging systems. The purpose of this work was to assess task-based performance of full field digital mammography (FFDM), digital breast tomosynthesis (DBT), and synthetic mammography (SM) using different phantom types, and to determine an accurate observer model for human readers. Images were acquired on a Hologic Selenia Dimensions system with a uniform and anthropomorphic phantom. A contrast detail insert of small, low-contrast disks was created using an inkjet printer with iodine-doped ink and inserted in the phantoms. The disks varied in diameter from 210 to 630 μm, and in contrast from 1.1% contrast to 2.2% in regular increments. Human and model observers performed a 4-alternative forced choice experiment. The models were a non-prewhitening matched filter with eye model (NPWE) and a channelized Hotelling observer with either Gabor channels (Gabor-CHO) or Laguerre-Gauss channels (LG-CHO). With the given phantoms, reader scores were higher in FFDM and DBT than SM. The structure in the phantom background had a bigger impact on outcome for DBT than for FFDM or SM. All three model observers showed good correlation with humans in the uniform background, with ρ between 0.89 and 0.93. However, in the structured background, only the CHOs had high correlation, with ρ=0.92 for Gabor-CHO, 0.90 for LG-CHO, and 0.77 for NPWE. Because results of any analysis can depend on the phantom structure, conclusions of modality performance may need to be taken in the context of an appropriate model observer and a realistic phantom.

  7. Compatibility tests between Jarytherm DBT synthetic oil and solid materials from wastes

    NASA Astrophysics Data System (ADS)

    Fasquelle, Thomas; Falcoz, Quentin; Neveu, Pierre; Flamant, Gilles; Walker, Jérémie

    2016-05-01

    Direct thermocline thermal energy storage is the cheapest sensible thermal energy storage configuration. Indeed, a thermocline tank consists in one tank instead of two and reduces costs. Thermocline thermal energy storages are often filled with cheap solid materials which could react with the heat transfer fluid in the case of incompatibility. PROMES laboratory is building a pilot-scale parabolic trough solar loop including a direct thermocline thermal energy storage system. The working fluid will be a synthetic oil, the Jarytherm® DBT, and the thermal energy storage tank will be filled with stabilized solid materials elaborated from vitrified wastes. Compatibility tests have been conducted in order to check on one hand if the thermo-mechanical properties and life time of the energy storage medium are not affected by the contact with oil and, on the other hand, if the thermal oil performances are not degraded by the solid filler. These experiments consisted in putting in contact the oil and the solid materials in small tanks. In order to discriminate the solid materials tested in the shortest time, accelerating aging conditions at 330 °C for 500 hours were used. The measurements consisted in X-Ray Diffraction and Scanning Electron Microscopy for the solids, and thermo-physical and chemical properties measurements for the oil. Regarding the solid samples, their crystalline structure did not change during the test, but it is difficult to conclude about their elementary composition and they seem to absorb oil. While thermal properties still makes Jarytherm® DBT a good heat transfer fluid after the accelerated aging tests, this study results in differentiating most compatible materials. Thus according to our study, Jarytherm® DBT can be used in direct thermocline thermal energy storage applications when compatibility of the solid material has been demonstrated.

  8. Refractory depression: mechanisms and evaluation of radically open dialectical behaviour therapy (RO-DBT) [REFRAMED]: protocol for randomised trial

    PubMed Central

    Lynch, T R; Whalley, B; Hempel, R J; Byford, S; Clarke, P; Clarke, S; Kingdon, D; O'Mahen, H; Russell, I T; Shearer, J; Stanton, M; Swales, M; Watkins, A; Remington, B

    2015-01-01

    Introduction Only 30–40% of depressed patients treated with medication achieve full remission. Studies that change medication or augment it by psychotherapy achieve only limited benefits, in part because current treatments are not designed for chronic and complex patients. Previous trials have excluded high-risk patients and those with comorbid personality disorder. Radically Open Dialectical Behaviour Therapy (RO-DBT) is a novel, transdiagnostic treatment for disorders of emotional over-control. The REFRAMED trial aims to evaluate the effectiveness and cost-effectiveness of RO-DBT for patients with treatment-resistant depression. Methods and analysis REFRAMED is a multicentre randomised controlled trial, comparing 7 months of individual and group RO-DBT treatment with treatment as usual (TAU). Our primary outcome measure is depressive symptoms 12 months after randomisation. We shall estimate the cost-effectiveness of RO-DBT by cost per quality-adjusted life year. Causal analyses will explore the mechanisms by which RO-DBT is effective. Ethics and dissemination The National Research Ethics Service (NRES) Committee South Central – Southampton A first granted ethical approval on 20 June 2011, reference number 11/SC/0146. Trial registration number ISRCTN85784627. PMID:26187121

  9. Computer-aided detection of microcalcifications in digital breast tomosynthesis (DBT): a multichannel signal detection approach on projection views

    NASA Astrophysics Data System (ADS)

    Wei, Jun; Chan, Heang-Ping; Hadjiiski, Lubomir; Helvie, Mark A.; Zhou, Chuan; Lu, Yao

    2012-03-01

    DBT is one of the promising imaging modalities that may improve the sensitivity and specificity for breast cancer detection. We are developing a computer-aided detection (CADe) system for clustered microcalcifications (MC) in DBT. A data set of two-view DBTs from 42 breasts was collected with a GE prototype system. We investigated a 2D approach to MC detection using projection view (PV) images rather than reconstructed 3D DBT volume. Our 2D approach consisted of two major stages: 1) detecting individual MC candidates on each PV, and 2) correlating the MC candidates from the different PVs and detecting clusters in the breast volume. With the MC candidates detected by prescreening on PVs, a trained multi-channel (MCH) filter bank was used to extract signal response from each MC candidate. A ray-tracing process was performed to fuse the MCH responses and localize the MC candidates in 3D using the geometrical information of the DBT system. Potential MC clusters were then identified by dynamic clustering of the MCs in 3D. A two-fold cross-validation method was used to train and test the CADe system. The detection performance of clustered MCs was assessed by free receiver operating characteristic (FROC) analysis. It was found that the CADe system achieved a case-based sensitivity of 90% at an average false positive rate of 2.1 clusters per DBT volume. Our study demonstrated that the CADe system using 2D MCH filter bank is promising for detection of clustered MCs in DBT.

  10. 18F-AFETP, 18F-FET, and 18F-FDG Imaging of Mouse DBT Gliomas

    PubMed Central

    Sai, Kiran Kumar Solingapuram; Huang, Chaofeng; Yuan, Liya; Zhou, Dong; Piwnica-Worms, David; Garbow, Joel R.; Engelbach, John A.; Mach, Robert H.; Rich, Keith M.; McConathy, Jonathan

    2013-01-01

    The goal of this study was to evaluate the 18F-labeled nonnatural amino acid (S)-2-amino-3-[1-(2-18F-fluoroethyl)-1H-[1,2,3]triazol-4-yl]propanoic acid (18F-AFETP) as a PET imaging agent for brain tumors and to compare its effectiveness with the more-established tracers O-(2-18F-fluoroethyl)-L-tyrosine (18F-FET) and 18F-FDG in a murine model of glioblastoma. The tracer 18F-AFETP is a structural analog of histidine and is a lead compound for imaging cationic amino acid transport, a relatively unexplored target for oncologic imaging. Methods 18F-AFETP was prepared using the click reaction. BALB/c mice with intracranially implanted delayed brain tumor (DBT) gliomas (n = 4) underwent biodistribution and dynamic small-animal PET imaging for 60 min after intravenous injection of 18F-AFETP. Tumor and brain uptake of 18F-AFETP were compared with those of 18F-FDG and 18F-FET through small-animal PET analyses. Results 18F-AFETP demonstrated focally increased uptake in tumors with good visualization. Peak tumor uptake occurred within 10 min of injection, with stable or gradual decrease over time. All 3 tracers demonstrated relatively high uptake in the DBTs throughout the study. At late time points (47.5–57.5 min after injection), the average standardized uptake value with 18F-FDG (1.9 ± 0.1) was significantly greater than with 18F-FET (1.1 ± 0.1) and 18F-AFETP (0.7 ± 0.2). The uptake also differed substantially in normal brain, with significant differences in the standardized uptake values at late times among 18F-FDG (1.5 ± 0.2), 18F-FET (0.5 ± 0.05), and 18F-AFETP (0.1 ± 0.04). The resulting average tumor-to-brain ratio at the late time points was significantly higher for 18F-AFETP (7.5 ± 0.1) than for 18F-FDG (1.3 ± 0.1) and 18F-FET (2.0 ± 0.3). Conclusion 18F-AFETP is a promising brain tumor imaging agent, providing rapid and persistent tumor visualization, with good tumor–to–normal-brain ratios in the DBT glioma model. High tumor-to-brain, tumor

  11. Impact of a Dialectic Behavior Therapy - Corrections Modified (DBT-CM) Upon Behaviorally Challenged Incarcerated Male Adolescents

    PubMed Central

    Shelton, Deborah; Kesten, Karen; Zhang, Wanli; Trestman, Robert

    2011-01-01

    Purpose This article reports the findings of a Dialectical Behavioral Therapy- Corrections Modified (DBT-CM) intervention upon difficult to manage, impulsive and/or aggressive incarcerated male adolescents. Methods A secondary analysis of a sub-sample of 38 male adolescents who participated in the study was conducted. A one-group pretest-posttest design was used; descriptive statistics and t-tests were conducted. Results Significant changes were found in physical aggression, distancing coping methods and number of disciplinary tickets for behavior. Conclusion The study supports the value of DBT-CM for management of incarcerated male adolescents with difficult to manage aggressive behaviors. PMID:21501287

  12. A Pilot Study of the DBT Coach: An Interactive Mobile Phone Application for Individuals with Borderline Personality Disorder and Substance Use Disorder

    ERIC Educational Resources Information Center

    Rizvi, Shireen L.; Dimeff, Linda A.; Skutch, Julie; Carroll, David; Linehan, Marsha M.

    2011-01-01

    Dialectical behavior therapy (DBT) has received strong empirical support and is practiced widely as a treatment for borderline personality disorder (BPD) and BPD with comorbid substance use disorders (BPD-SUD). Therapeutic success in DBT requires that individuals generalize newly acquired skills to their natural environment. However, there have…

  13. Improvement of image performance in digital breast tomosynthesis (DBT) by incorporating a compressed-sensing (CS)-based deblurring scheme

    NASA Astrophysics Data System (ADS)

    Kim, Kyuseok; Park, Yeonok; Cho, Heemoon; Cho, Hyosung; Je, Uikyu; Park, Chulkyu; Lim, Hyunwoo; Park, Soyoung; Woo, Taeho; Choi, Sungil

    2016-10-01

    In this work, we investigated a compressed-sensing (CS)-based deblurring scheme incorporated with the total-variation (TV) regularization penalty for image deblurring of high accuracy and adopted it into the image reconstruction in conventional digital breast tomosynthesis (DBT). We implemented the proposed algorithm and performed a systematic simulation to demonstrate its viability for improving the image performance in DBT as well as two-dimensional (2D) mammography. In the simulation, blurred noisy projection images of a 3D numerical breast phantom were generated by convolving their original (or exact) version by a designed 2D Gaussian filter kernel (standard deviation=2 in pixel unit, kernel size=11×11), followed by adding Gaussian noise (mean=0, variance=0.05), and deblurred by using the algorithm before performing the DBT reconstruction procedure. Here the projection images were taken with a half tomographic angle of θ=20° and an angle step of Δθ=2°. We investigated the image performance of the reconstructed DBT images quantitatively in terms of the modulation and the slice-sensitive profile (SSP).

  14. DBT Telephone Skills Coaching with Eating Disordered Clients: Who Calls, for What Reasons, and for How Long?

    ERIC Educational Resources Information Center

    Limbrunner, Heidi M.; Ben-Porath, Denise D.; Wisniewski, Lucene

    2011-01-01

    The goal of this paper is to report on the typology, frequency, and duration of intersession calls placed by outpatient eating disorder clients to their therapists. Participants were 17 women, offered DBT after-hours telephone coaching adapted for individuals with eating disorders. Results indicated that clients used telephone coaching primarily…

  15. Efficient Deep-Blue Electroluminescence Based on Phenanthroimidazole-Dibenzothiophene Derivatives with Different Oxidation States of the Sulfur Atom.

    PubMed

    Tang, Xiangyang; Shan, Tong; Bai, Qing; Ma, Hongwei; He, Xin; Lu, Ping

    2017-03-02

    Developing efficient deep-blue materials is a long-term research focus in the field of organic light-emitting diodes (OLEDs). In this paper, we report two deep-blue molecules, PITO and PISF, which share similar chemical structures but exhibit different photophysical and device properties. These two molecules consist of phenanthroimidazole and dibenzothiophene analogs. The distinction of their chemical structures lies in the different oxidation states of the S atom. For PITO, the S atom is oxidized and the resulting structure dibenzothiophene S,S-dioxide becomes electron deficient. Therefore, PITO displays remarkable solvatochromism, implying a charge-transfer (CT) excited state formed between the donor (D) phenanthroimidazole and acceptor (A) dibenzothiophene S,S-dioxide. For PISF, it is constituted of phenanthroimidazole and dibenzothiophene in which the S atom is not oxidized. PISF displays locally excited (LE) emission with little solvatochromism. Compared with PISF, the D-A molecule PITO with an electron-deficient group shows a much lower LUMO energy level, which is in favor of electron injection in device. In addition, PITO exhibits more balanced carrier transport. However, PISF is capable of emitting in the shorter wavelength region, which is beneficial to obtain better color purity. The doped electroluminescence (EL) device of the D-A molecule PITO manifests deep-blue emission with CIE coordinates of (0.15, 0.08) and maximum external quantum efficiency (EQE) of 4.67 %. The doped EL device of the LE molecule PISF, however, reveals an even bluer emission with CIE coordinates of (0.15, 0.06) and a maximum EQE of 4.08 %.

  16. A pilot study of the DBT coach: an interactive mobile phone application for individuals with borderline personality disorder and substance use disorder.

    PubMed

    Rizvi, Shireen L; Dimeff, Linda A; Skutch, Julie; Carroll, David; Linehan, Marsha M

    2011-12-01

    Dialectical behavior therapy (DBT) has received strong empirical support and is practiced widely as a treatment for borderline personality disorder (BPD) and BPD with comorbid substance use disorders (BPD-SUD). Therapeutic success in DBT requires that individuals generalize newly acquired skills to their natural environment. However, there have been only a limited number of options available to achieve this end. The primary goal of this research was to develop and test the feasibility of the DBT Coach, a software application for a smartphone, designed specifically to enhance generalization of a specific DBT skill (opposite action) among individuals with BPD-SUD. We conducted a quasiexperimental study in which 22 individuals who were enrolled in DBT treatment programs received a smartphone with the DBT Coach for 10 to 14 days and were instructed to use it as needed. Participants used the DBT Coach an average of nearly 15 times and gave high ratings of helpfulness and usability. Results indicate that both emotion intensity and urges to use substances significantly decreased within each coaching session. Furthermore, over the trial period, participants reported a decrease in depression and general distress. Mobile technology offering in vivo skills coaching may be a useful tool for reducing urges to use substances and engage in other maladaptive behavior by directly teaching and coaching in alternative, adaptive coping behavior.

  17. Rational preparation of dibenzothiophene-imprinted polymers by surface imprinting technique combined with atom transfer radical polymerization

    NASA Astrophysics Data System (ADS)

    Yang, Wenming; Liu, Lukuan; Zhou, Zhiping; Liu, Hong; Xie, Binze; Xu, Wanzhen

    2013-10-01

    A computational simulation method is introduced to simulate the dibenzothiophene-monomer pre-assembly system of molecular imprinted polymers. The interaction type and intensity between dibenzothiophene and monomer are discussed from the binding energy and spatial position distribution. The simulation and analysis results indicate that the amount of the function monomer is not the more the better in preparing molecular imprinted polymers. Based on the above results, a novel dibenzothiophene-imprinted polymers with the favorable specific adsorption effect was prepared by surface imprinting technique combined with atom transfer radical polymerization. This combined technologies are used for preparing a desulfurization adsorbent for the first time. Various measures were selected to characterize the structure and morphology of the prepared adsorbent. The characterization results show that the adsorbent has suitable features for further adsorption process. A series of static adsorption experiments were conducted to analyze its adsorption performance. The adsorption process follows Elovich model by the kinetic analysis and Sips equation by the isothermal analysis. The approach we described will provide another opportunity in the deep desulfurization field.

  18. Targeting binge eating through components of dialectical behavior therapy: preliminary outcomes for individually supported diary card self-monitoring versus group-based DBT.

    PubMed

    Klein, Angela S; Skinner, Jeremy B; Hawley, Kristin M

    2013-12-01

    The current study examined two condensed adaptations of dialectical behavior therapy (DBT) for binge eating. Women with full- or sub-threshold variants of either binge eating disorder or bulimia nervosa were randomly assigned to individually supported self-monitoring using adapted DBT diary cards (DC) or group-based DBT, each 15 sessions over 16 weeks. DC sessions focused on problem-solving diary card completion issues, praising diary card completion, and supporting nonjudgmental awareness of eating-related habits and urges, but not formally teaching DBT skills. Group-based DBT included eating mindfulness, progressing through graded exposure; mindfulness, emotion regulation, and distress tolerance skills; and coaching calls between sessions. Both treatments evidenced large and significant improvements in binge eating, bulimic symptoms, and interoceptive awareness. For group-based DBT, ineffectiveness, drive for thinness, body dissatisfaction, and perfectionism also decreased significantly, with medium to large effect sizes. For DC, results were not significant but large in effect size for body dissatisfaction and medium in effect size for ineffectiveness and drive for thinness. Retention for both treatments was higher than recent trends for eating disorder treatment in fee-for-service practice and for similar clinic settings, but favored DC, with the greater attrition of group-based DBT primarily attributed to its more intensive and time-consuming nature, and dropout overall associated with less pretreatment impairment and greater interoceptive awareness. This preliminary investigation suggests that with both abbreviated DBT-based treatments, substantial improvement in core binge eating symptoms is possible, enhancing potential avenues for implementation beyond more time-intensive DBT.

  19. Optical and electroluminescent properties of a number of new derivatives of divinyl dibenzothiophene sulfone

    NASA Astrophysics Data System (ADS)

    Kukhto, A. V.; Kopylova, T. N.; Gadirov, R. M.; Degtyarenko, K. N.; Nikonova, E. N.; Solodova, T. A.; Kukhto, I. N.

    2016-02-01

    Photoluminescent and electroluminescent properties of four new bipolar linear derivatives of divinyl dibenzothiophene sulfone are studied. It is found that amorphous films of solutions, as well as films of the compounds under study in the poly(N-vinylcarbazole) matrix, have a rather high quantum yield of photoluminescence in the blue and blue-green spectrum regions. Bright blue electroluminescence is obtained in the samples with a structure of ITO/PEDOT:PSS/TPD/OC/LiF/Al using vacuum deposition of the compounds under study and in the single-layer ITO/PEDOT:PSS/PVK:OC/LiF/Al structure when applied from the solution with a threshold voltage of 2.5-3.5 V. The influence of a molecule structure on the spectra and quantum yield of fluorescence as well as on the electroluminescent properties of the compounds is shown. Results of quantum-chemical calculations in the context of the density functional theory of the structure and characteristics of main molecular orbitals are presented.

  20. Development and application of a channelized Hotelling observer for DBT optimization on structured background test images with mass simulating targets

    NASA Astrophysics Data System (ADS)

    Petrov, Dimitar; Michielsen, Koen; Cockmartin, Lesley; Zhang, Gouzhi; Young, Kenneth; Marshall, Nicholas; Bosmans, Hilde

    2016-03-01

    Digital breast tomosynthesis (DBT) is a 3D mammography technique that promises better visualization of low contrast lesions than conventional 2D mammography. A wide range of parameters influence the diagnostic information in DBT images and a systematic means of DBT system optimization is needed. The gold standard for image quality assessment is to perform a human observer experiment with experienced readers. Using human observers for optimization is time consuming and not feasible for the large parameter space of DBT. Our goal was to develop a model observer (MO) that can predict human reading performance for standard detection tasks of target objects within a structured phantom and subsequently apply it in a first comparative study. The phantom consists of an acrylic semi-cylindrical container with acrylic spheres of different sizes and the remaining space filled with water. Three types of lesions were included: 3D printed spiculated and non-spiculated mass lesions along with calcification groups. The images of the two mass lesion types were reconstructed with 3 different reconstruction methods (FBP, FBP with SRSAR, MLTRpr) and read by human readers. A Channelized Hotelling model observer was created for the non-spiculated lesion detection task using five Laguerre-Gauss channels, tuned for better performance. For the non-spiculated mass lesions a linear relation between the MO and human observer results was found, with correlation coefficients of 0.956 for standard FBP, 0.998 for FBP with SRSAR and 0.940 for MLTRpr. Both the MO and human observer percentage correct results for the spiculated masses were close to 100%, and showed no difference from each other for every reconstruction algorithm.

  1. Dibenzothiophene-S,S-dioxide and Bispyridinium-Based Cationic Polyfluorene Derivative as an Efficient Cathode Modifier for Polymer Solar Cells.

    PubMed

    Chen, Guiting; Liu, Sha; Xu, Jin; He, Ruifeng; He, Zhicai; Wu, Hong-Bin; Yang, Wei; Zhang, Bin; Cao, Yong

    2017-02-08

    A novel n-type conjugated polymer containing dibenzothiophene-S,S-dioxide (FSO), bispyridinium, and fluorene scaffolds in the backbone (PFSOPyCl) was synthesized and used in the cathode interfacial layers (CILs) of conventional polymer solar cells (PSCs). The high electron affinities and large planar structures of the FSO and bispyridinium units endowed this polymer with good energy level alignments with [6,6]-phenyl-C71 butyric acid methyl ester (PC71BM) and metal cathode, and excellent electron transport and extraction properties. Polymer solar cells (PSCs) based on the poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT):PC71BM system with PFSOPyCl CIL exhibited simultaneous enhancement in open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF), while the power conversion efficiency increased from 5.47% to 6.79%, relative to the bare Al device. Besides, PSC based on the poly[4,8-bis(2-ethylhexyloxyl)benzo[1,2-b:4,5-b']dithio-phene-2,6-diyl-alt-ethylhexyl-3-fluorothithieno [3,4-b]thiophene-2-carboxylate-4,6-diyl] (PTB7):PC71BM system achieved a PCE of 8.43% when using PFSOPyCl as CIL. Hence, PFSOPyCl is a promising candidate CIL for PSCs.

  2. In vitro approaches to evaluate toxicity induced by organotin compounds tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) in neuroblastoma cells.

    PubMed

    Ferreira, Martiña; Blanco, Lucía; Garrido, Alejandro; Vieites, Juan M; Cabado, Ana G

    2013-05-01

    The toxic effects of the organotin compounds (OTCs) monobutyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) were evaluated in vitro in a neuroblastoma human cell line. Mechanisms of cell death, apoptosis versus necrosis, were studied by using several markers: inhibition of cell viability and proliferation, F-actin, and mitochondrial membrane potential changes as well as reactive oxygen species (ROS) production and DNA fragmentation. The most toxic effects were detected with DBT and TBT even at very low concentrations (0.1-1 μM). In contrast, MBT induced lighter cytotoxic changes at the higher doses tested. None of the studied compounds stimulated propidium iodide uptake, although the most toxic chemical, TBT, caused lactate dehydrogenase release at the higher concentrations tested. These findings suggest that in neuroblastoma, OTC-induced cytotoxicity involves different pathways depending on the compound, concentration, and incubation time. A screening method for DBT and TBT quantification based on cell viability loss was developed, allowing a fast detection alternative to complex methodology.

  3. Templated growth of PFO-DBT nanorod bundles by spin coating: effect of spin coating rate on the morphological, structural, and optical properties.

    PubMed

    Fakir, Muhamad Saipul; Supangat, Azzuliani; Sulaiman, Khaulah

    2014-01-01

    In this study, the spin coating of template-assisted method is used to synthesize poly[2,7-(9,9-dioctylfluorene)-alt-4,7-bis(thiophen-2-yl)benzo-2,1,3-thiadiazole] (PFO-DBT) nanorod bundles. The morphological, structural, and optical properties of PFO-DBT nanorod bundles are enhanced by varying the spin coating rate (100, 500, and 1,000 rpm) of the common spin coater. The denser morphological distributions of PFO-DBT nanorod bundles are favorably yielded at the low spin coating rate of 100 rpm, while at high spin coating rate, it is shown otherwise. The auspicious morphologies of highly dense PFO-DBT nanorod bundles are supported by the augmented absorption and photoluminescence.

  4. PET Imaging Evaluation of [18F]DBT-10, a Novel Radioligand Specific to α7 Nicotinic Acetylcholine Receptors, in Nonhuman Primates

    PubMed Central

    Hillmer, Ansel T.; Zheng, Ming-Qiang; Li, Songye; Scheunemann, Matthias; Lin, Shu-fei; Holden, Daniel; Labaree, David; Ropchan, Jim; Teodoro, Rodrigo; Deuther-Conrad, Winnie; Carson, Richard E.; Brust, Peter; Huang, Yiyun

    2015-01-01

    Purpose PET radioligands specific to α7 nicotinic acetylcholine receptors (nAChRs) afford in vivo imaging of this receptor for neuropathologies such as Alzheimer’s disease, schizophrenia, and substance abuse. This work aims to characterize the kinetic properties of an α7-nAChR specific radioligand, 7-(1,4-diazabicyclo[3.2.2]nonan-4-yl)-2-[18F]-fluorodibenzo[b,d]thiophene 5,5-dioxide ([18F]DBT-10), in nonhuman primates. Methods [18F]DBT-10 was produced via nucleophilic substitution of the nitro-precursor. Four Macaca mulatta subjects were imaged with [18F]DBT-10 PET, with measurement of [18F]DBT-10 parent concentrations and metabolism in arterial plasma. Baseline PET scans were acquired for all subjects. Following one scan, ex vivo analysis of brain tissue was performed to inspect for radiolabeled metabolites in brain. Three blocking scans with 0.69 and 1.24 mg/kg of the α7-nAChR-specific ligand ASEM were also acquired to assess dose-dependent blockade of [18F]DBT-10 binding. Kinetic analysis of PET data was performed using the metabolite-corrected input function to calculate the parent fraction corrected total distribution volume (VT/fP). Results [18F]DBT-10 was produced within 90 min at high specific activities of 428±436 GBq/μmol at end of synthesis. Metabolism of [18F]DBT-10 varied across subjects, stabilizing by 120 min post-injection at parent fractions of 15–55%. Uptake of [18F]DBT-10 in brain occurred rapidly, reaching peak SUVs of 2.9–3.7 within 30 min. The plasma free fraction was 18.8±3.4%. No evidence for radiolabeled [18F]DBT-10 metabolites was found in ex vivo brain tissue samples. Kinetic analysis of PET data was best described by the two-tissue compartment model. Estimated VT/fP values were 193–376 mL/cm3 across regions, with regional rank order of thalamus > frontal cortex > striatum > hippocampus > occipital cortex > cerebellum > pons. Dose dependent blockade of [18F]DBT-10 binding by structural analog ASEM was observed throughout the

  5. Ferulic Acid Orchestrates Anti-Oxidative Properties of Danggui Buxue Tang, an Ancient Herbal Decoction: Elucidation by Chemical Knock-Out Approach

    PubMed Central

    Gong, Amy G. W.; Huang, Vincent Y.; Wang, Huai Y.; Lin, Huang Q.; Dong, Tina T. X.; Tsim, Karl W. K.

    2016-01-01

    Ferulic acid, a phenolic acid derived mainly from a Chinese herb Angelica Sinensis Radix (ASR), was reported to reduce the formation of free radicals. Danggui Buxue Tang (DBT), a herbal decoction composing of Astragali Radix (AR) and ASR, has been utilized for more than 800 years in China having known anti-oxidative property. Ferulic acid is a major active ingredient in DBT; however, the role of ferulic acid within the herbal mixture has not been resolved. In order to elucidate the function of ferulic acid within this herbal decoction, a ferulic acid-depleted herbal decoction was created and named as DBTΔfa. The anti-oxidative properties of chemically modified DBT decoction were systemically compared in cultured H9C2 rat cardiomyoblast cell line. The application of DBT and DBTΔfa into the cultures showed functions in (i) decreasing the reactive oxygen species (ROS) formation, detected by laser confocal; (ii) increasing of the activation of Akt; (iii) increasing the transcriptional activity of anti-oxidant response element (ARE); and (iv) increasing the expressions of anti-oxidant enzymes, i.e. NQO1 and GCLM. In all scenario, the aforementioned anti-oxidative properties of DBTΔfa in H9C2 cells were significantly reduced, as compared to authentic DBT. Thus, ferulic acid could be an indispensable chemical in DBT to orchestrate multi-components of DBT as to achieve maximal anti-oxidative functions. PMID:27824860

  6. Production and characterization of a novel yeast extracellular invertase activity towards improved dibenzothiophene biodesulfurization.

    PubMed

    Arez, Bruno F; Alves, Luís; Paixão, Susana M

    2014-11-01

    The main goal of this work was the production and characterization of a novel invertase activity from Zygosaccharomyces bailii strain Talf1 for further application to biodesulfurization (BDS) in order to expand the exploitable alternative carbon sources to renewable sucrose-rich feedstock. The maximum invertase activity (163 U ml(-1)) was achieved after 7 days of Z. bailii strain Talf1 cultivation at pH 5.5-6.0, 25 °C, and 150 rpm in Yeast Malt Broth with 25 % Jerusalem artichoke pulp as inducer substrate. The optimum pH and temperature for the crude enzyme activity were 5.5 and 50 °C, respectively, and moreover, high stability was observed at 30 °C for pH 5.5-6.5. The application of Talf1 crude invertase extract (1 %) to a BDS process by Gordonia alkanivorans strain 1B at 30 °C and pH 7.5 was carried out through a simultaneous saccharification and fermentation (SSF) approach in which 10 g l(-1) sucrose and 250 μM dibenzothiophene were used as sole carbon and sulfur sources, respectively. Growth and desulfurization profiles were evaluated and compared with those of BDS without invertase addition. Despite its lower stability at pH 7.5 (loss of activity within 24 h), Talf1 invertase was able to catalyze the full hydrolysis of 10 g l(-1) sucrose in culture medium into invert sugar, contributing to a faster uptake of the monosaccharides by strain 1B during BDS. In SSF approach, the desulfurizing bacterium increased its μmax from 0.035 to 0.070 h(-1) and attained a 2-hydroxybiphenyl productivity of 5.80 μM/h in about 3 days instead of 7 days, corresponding to an improvement of 2.6-fold in relation to the productivity obtained in BDS process without invertase addition.

  7. Detection of dibenzothiophene in mussel, Mytilus edulis, as a marker of pollution by organosulfur compounds in a marine environment

    SciTech Connect

    Kira, S.; Izumi, T.; Ogata, M.

    1983-11-01

    Organosulfur compounds are minor components of crude oil and of some fuel oils. Although the quantity of these compounds depends on the source of production, generally it ranges from 0.002 to nearly 30% in crude oil, found as sulfur containing hydrocarbons. Mussels are a well-known biological monitor of marine pollutants which scientists call ''the mussel watch''. But few reports have been published on organosulfur compound contamination in field mussel samples. In the present study, the authors identified several organosulfur compound contamination in field mussel samples. In the present study, the authors identified several organosulfur compounds through GC-MS, and measured the levels of DBT through GC-flame photometric detector (GC-FPD), in both mussels and in water of the environment. The calculated concentration ratio of DBT in mussels to that in water ranged up to 500 in the field sample and 800 or higher after and experimental exposure. The estimated biological half-life or DBT from field mussel samples was about 9 days in clean sea water.

  8. Reactive carbon microspheres prepared by surface-grafting 4-(chloromethyl)phenyltrimethoxysilane for preparing molecularly imprinted polymer

    NASA Astrophysics Data System (ADS)

    Liu, Weifeng; Zhao, Huijun; Yang, Yongzhen; Liu, Xuguang; Xu, Bingshe

    2013-07-01

    Carbon microspheres (CMSs) were oxidized by a mixture of concentrated sulfuric and nitric acids, and modified by 4-(chloromethyl)phenyltrimethoxysilane to give reactive surface. Then, by adopting the surface molecular imprinting technique, dibenzothiophene (DBT) molecule-imprinted material MIP-DBT/CMSs was prepared with methacrylic acid as functional monomer and ethylene glycol dimethacrylate as crosslinking agent. The binding character of MIP-DBT/CMSs toward DBT was investigated with static method by gas chromatography, using fluorene and biphenyl as the reference substances which are similar to DBT in chemical structure to a certain extent. The effects of reaction time, temperature, and coupling agent concentration during silanization were investigated. The results show that the optimized conditions of silanization were 0.3 g oxidized-CMSs, 5% of CMTMS, 80 °C and 4 h. On the basis of silanized-CMSs, MIP-DBT/CMSs was synthesized. The adsorption results show that MIP-DBT/CMSs possessed strong adsorption ability for DBT. The maximal adsorption amount reached up 88.83 mg/g, in comparison with 44.51 mg/g of the non-imprinted polymer. In addition, MIP-DBT/CMSs exhibited a good selective adsorption capacity for DBT than fluorene (19.86 mg/g) and biphenyl (15.33 mg/g). The adsorption behavior followed the pseudo second order kinetic model. And the Freundlich isotherm was found to describe well the equilibrium adsorption data.

  9. The ratios of dibenzothiophene to phenanthrene and pristane to phytane as indicators of depositional environment and lithology of petroleum source rocks

    SciTech Connect

    Hughes, W.B.; Holba, A.G.; Dzou, L.I.P.

    1995-09-01

    The ratio of dibenzothiophene to phenanthrene and the ratio of pristane to phytane, when coupled together, provide a novel and convenient way to infer crude oil source rock depositional environments and lithologies. Such knowledge can significantly assist in identifying the source formation(s) in a basin thereby providing valuable guidance for further exploration. The ability to infer this information from analysis of a crude oil is especially valuable as frequently the earliest samples in a new area may be shows and/or drill stem test samples from exploratory wells which are characteristically drilled on structural highs stratigraphically remote from the source formation(s). A cross-plot of dibenzothiophene/phenanthrene versus the pristane/phytane ratios measured on seventy-five crude oils from forty-one known source rocks ranging in age from Ordovician to Miocene consistently classified the oils into the following environment/lithology groups: marine carbonate; marine carbonate/mixed and lacustrine sulfate-rich; lacustrine sulfate-poor; marine and lacustrine shale; and fluvial/deltaic carbonaceous shale and coal. The dibenzothiophene to phenanthrene and the pristane to phytane ratios can also be used to classify source rock paleodepositional environments. The classification scheme is based on the premise that these ratios reflect the different Eh-pH regimes resulting from the significant microbiological and chemical processes occurring during deposition and early diagenesis of sediments. The dibenzothiophene/phenanthrene ratio assesses the availability of reduced sulfur for incorporation into organic matter and the pristane/phytane ratio assesses the redox conditions within the depositional environment. Interpretation of these ratios has been aided by quantitative biomarker analysis and by carbon isotope data for pristane and phytane obtained by gas chromatography-isotope ratio mass spectrometry.

  10. Organic-inorganic hybrid nanocomposite for enhanced photo-sensing of PFO-DBT:MEH-PPV:PC71BM blend-based photodetector

    NASA Astrophysics Data System (ADS)

    Zafar, Qayyum; Najeeb, Mansoor Ani; Ahmad, Zubair; Sulaiman, Khaulah

    2015-09-01

    The sensing parameters of previously reported PFO-DBT:MEH-PPV:PC71BM ternary blend-based organic photodetector have been improved in the present study. Improvement has been successfully demonstrated by doping TiO2 nanoparticles in the PEDOT:PSS thin film. TiO2 nanoparticles of 50, 100 and 250 nm diameters have initially been dispersed in PEDOT:PSS, and the resulting suspension has been spun coated on glass substrates and subjected to UV/vis and PL study. Thin film of PEDOT:PSS-TiO2 (100 nm) has shown maximum quenching in PL spectra, along with fairly good visible-light absorption. For further studies, 5 wt% TiO2 (100 nm) nanoparticles dispersion in PEDOT:PSS has been utilized for the fabrication of ITO/PEDOT:PSS-TiO2/PFO-DBT:MEH-PPV:PC71BM/Al photodiode. The PEDOT:PSS-TiO2 suspension has been spun coated onto the ITO substrates primarily and annealed to densify the film by vaporizing water contents in the film. A ternary blend of PFO-DBT:MEH-PPV:PC71BM in optimized volumetric ratio has been sequentially spun-cast to serve as a photoactive film. Significantly improved values of the sensing parameters such as responsivity (4 mA/W) and photo-to-dark current ratio ( 6.4 × 104) have also been found. Response/recovery times of the fabricated sensor remain almost the same (<1 s) as previously reported for PFO-DBT:MEH-PPV:PC71BM ternary blend.

  11. Preparation of organic sulfur adsorbent from coal for adsorption of dibenzothiophene-type compounds in diesel fuel

    SciTech Connect

    Cigdem Shalaby; Xiaoliang Ma; Anning Zhou; Chunshan Song

    2009-05-15

    High-performance organic sulfur adsorbents (OSA) have been prepared from coal by chemical activation for selective adsorption of the refractory sulfur compounds, such as 4-methyl dibenzothiophene and 4,6-dimethyldibenzothiophene, in diesel fuel. The performance of the prepared OSAs for adsorptive desulfurization (ADS) was evaluated in batch and flow adsorption systems at room temperature using a model diesel fuel. It was found that coal rank and preparation conditions, including activation agents (NaOH, KOH, and NaOH + KOH) and their ratio to coal, activation temperature, and time have significant impacts on the yield and ADS performance of the OSAs. The high-performance OSAs can be prepared from different ranks of coal by using NaOH + KOH as an activation agent with an activating-agent-to-coal ratio of 3.5. The yield of OSA increased in the order of lignite < high volatile bituminous coal < medium volatile bituminous coal < anthracite. The OSA-A, which was derived from an anthracite with the highest yield (68 wt %) by the activation at 650{sup o}C for 1 h, gave the best ADS performance among the OSAs from all coal samples tested. The sulfur adsorption capacity of OSA-A reached 0.281 mmol-S/g-A at an equilibrium sulfur concentration of 50 ppmw in the model diesel fuel, which was 155% higher than a commercial coal-derived activated carbon and 35% higher than the best commercial activated carbon among all commercial activated carbons examined in our laboratory. The higher ADS capacity of OSA-A can be attributed to its significantly higher density (2.77 {mu}mol/m{sup 2}) of the adsorption sites on the surface as determined by Langmuir adsorption isotherm, which is related to its oxygen-containing functional groups on the carbonaceous surface as revealed by temperature-programmed desorption analysis. 57 refs., 10 figs., 6 tabs.

  12. Sudden losses and sudden gains during a DBT-PTSD treatment for posttraumatic stress disorder following childhood sexual abuse

    PubMed Central

    Krüger, Antje; Ehring, Thomas; Priebe, Kathlen; Dyer, Anne S.; Steil, Regina; Bohus, Martin

    2014-01-01

    Background Exposure-based treatment approaches are first-line interventions for patients suffering from posttraumatic stress disorder (PTSD). However, the dissemination of exposure-based treatments for PTSD is challenging, as a large proportion of clinicians report being concerned about symptoms worsening as a result of this type of intervention and are therefore reluctant to offer it to patients with PTSD. However, there is only little empirical evidence to date on the pattern of symptom worsening during exposure-based treatment for PTSD. Objective The goal of the present study was to explore the frequency of sudden losses and sudden gains in the course of an exposure-based treatment programme for female patients suffering from PTSD related to childhood sexual abuse who also show severe comorbidity. In addition, the relationship between sudden changes and treatment outcome was examined. Methods Female participants (N=74) were randomised to either a 12-week residential DBT-PTSD programme or a treatment-as-usual wait list. The pattern of symptom change was assessed via weekly assessments using the Posttraumatic Diagnostic Scale (PDS). Sudden changes were computed as suggested by the literature on sudden gains. Results During treatment, only one participant (3%) experienced a sudden loss, whereas 25% of participants experienced sudden gains. In the waiting condition, 8% of the participants experienced sudden losses and 5% experienced sudden gains during the same time period. No symptom worsening was observed in response to exposure sessions. However, sudden gains occurred during exposure and non-exposure treatment weeks. Patients with sudden gains showed better treatment outcome in the post-treatment and follow-up assessments. Conclusions Exposure-based treatment did not lead to PTSD symptom worsening in the study sample. Results show that sudden gains occur frequently during PTSD treatment and have a prognostic value for treatment outcome. PMID:25317254

  13. Full Field Digital Mammography (FFDM) versus CMOS Technology versus Tomosynthesis (DBT) - Which System Increases the Quality of Intraoperative Imaging?

    PubMed

    Schulz-Wendtland, R; Dilbat, G; Bani, M; Fasching, P A; Lux, M P; Wenkel, E; Schwab, S; Loehberg, C R; Jud, S M; Rauh, C; Bayer, C M; Beckmann, M W; Uder, M; Meier-Meitinger, M

    2012-06-01

    Aim: The aim of this prospective clinical study was to assess whether it would be possible to reduce the rate of re-excisions and improve the quality using CMOS technology or digital breast tomosynthesis (DBT) compared to a conventional FFDM system. Material and Methods: An invasive breast cancer (BI-RADS 5) was diagnosed in 200 patients in the period from 5/2011 to 1/2012. After histological verification, a breast-conserving therapy was performed with intraoperative imaging. Three different imaging systems were used: 1) Inspiration™ (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 l/mm as the standard; 2) BioVision™ (Bioptics, Tucson, USA), flat panel photodiode array, tungsten source, focus 0.05, resolution 50 µm pixel pitch, 12 l/mm; 3) Tomosynthesis (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 l/mm, range: 50°, 25 projections, scan time > 20 s, geometry: uniform scanning, reconstruction: filtered back projection. The 600 radiograms were prospectively shown to 3 radiologists. Results: Out of a total of 200 patients with histologically confirmed breast cancer (BI-RADS 6) 156 patients required no further operative therapy (re-excision) after breast-conserving therapy. A retrospective analysis (n = 44) showed an increase in sensitivity with tomosynthesis compared to the BioVision™ (CMOS technology) and the Inspiration™ at a magnification of 1.0 : 1.0 of 8 % (p < 0.05), i.e. re-excision would not have been necessary in 16 patients with tomosynthesis. Conclusions: The sensitivity of tomosynthesis for intraoperative radiography is significantly (p < 0.05) higher compared to both CMOS technology and an FFDM system with a conventional detector. Additional studies using higher magnification, e.g. 2.0 : 1.0, but no zooming will be necessary to evaluate the method further.

  14. Hydrodesulfurization of oxidized sulfur compounds in benzothiophene, methylbenzothiophene, and dibenzothiophene series over CoO-MoO/sub 3/-Al/sub 2/O/sub 3/ catalyst

    SciTech Connect

    Geneste, P.; Amblard, P.; Bonnet, M.; Graffin, P.

    1980-01-01

    Hydrodesulfurization experiments were carried out with a sulfided CoO-MoO/sub 3/-Al/sub 2/O/sub 3/ catalyst at various elevated pressures (30 to 70 atm) and temperatures (200 to 300/sup 0/C) under stirred batch reactor conditions. The reactants were hydrogen and pure sulfur compounds including dibenzothiophene, benzothiophene and its methyl derivatives, and their oxidized products, sulfoxides and sulfones. In the case of dibenzothiophene the reaction is the C-S bond scission without any observed hydrogenation of the aromatic ring. For the S-oxidized compounds a deoxygenation takes place first and the sulfide reacts as before. For benzothiophene (BT) and its methyl derivatives there is first a hydrogenation of the C/sub 2-3/ thiophenic double bond and then desulfurization leading to ethylbenzene derivatives. For the sulfoxides a deoxygenation takes place first but for the sulfones (BTO/sub 2/) as for the sulfide the hydrogenation is operative. Methyl substitution leads to a decrease in the rate of the hydrogenation step in the BT and BTO/sub 2/ series. A correlation, related to the overall aromaticity of the system, between the rate constants and the vertical ionization potential of the molecules, suggests that electronic effects may be preponderant. 35 references, 9 figures, 7 tables.

  15. Dibenzothiophene Sulfone-Based Phosphine Oxide Electron Transporters with Unique Asymmetry for High-Efficiency Blue Thermally Activated Delayed Fluorescence Diodes.

    PubMed

    Fan, Chaochao; Duan, Chunbo; Han, Chunmiao; Han, Bin; Xu, Hui

    2016-10-12

    Three asymmetrical electron transporters as dibenzothiophene sulfone (DBSO)-diphenylphosphine oxide (DPPO) hybrids, collectively named mnDBSODPO, were designed and prepared. All of these materials achieve the high triplet energy of ∼3.0 eV to restrain the exciton linkage from emissive layers. The dependence of inductive and steric effects for DPPO groups on the substitution position, the intermolecular interaction suppression, the encapsulations of high-polar DBSO cores, and the favorable electrical performance are successfully integrated on 36DBSODPO, which can simultaneously suppress the exciton quenching by formation of an interfacial dipole and enhancing the charge flux balance. As a result, 36DBSODPO endowed its tetralayer blue thermally activated delayed fluorescence (TADF) devices with impressive performance, including the maximum external quantum efficiency around 19%, and reduced efficiency roll-offs, which verifies the great potential of asymmetrical electron transporting materials for highly efficient TADF devices.

  16. Ranking inconsistencies in the assessment of digital breast tomosynthesis (DBT) reconstruction algorithms using a location-known task and a search task

    NASA Astrophysics Data System (ADS)

    He, Xin; Zeng, Rongping; Samuelson, Frank; Sahiner, Berkman

    2016-03-01

    In this work, we validated a task-based performance figure-of-merit (FOM) by investigating ranking inconsistencies due to lurking variable/factors. We applied a falsifiable search assessment theory to assessing digital breast tomosynthesis (DBT) image quality using a scanning channelized Hotelling observer (CHO) on a simulated DBT dataset. We compared the performance of five reconstruction algorithms: filter back projection (FBP), maximum likelihood (ML), simultaneous algebraic reconstruction technique (SART), total-variation regularized least square estimator (TVLS) with strong and mild regularization settings. The results showed that the location-known-exactly (LKE) detection performance was almost identical for the five reconstruction algorithms. However the search characteristic as described by effective set size (M*) and search AUC value, ranked them differently. To falsify/corroborate our evaluations on search characteristic and performance, we conducted an image-size test. This test demonstrated an agreement between theoretical predictions and empirically measured observer performance in absolute performance levels, except for the ML algorithm. We concluded that evidence corroborated our evaluations, except that for the ML algorithm where our evaluation was wrong. Further investigation of the wrong evaluation in the ML case revealed a lurking variable that affected system performance ranking in search when AUC value was used as the FOM. This further confirmed that our evaluation in its current form for the ML algorithm was indeed wrong. We also noted that the ranking inconsistencies exist even when the AUC value was used as the FOM, and the falsifiable nature of M* allowed such inconsistencies to be identified.

  17. Annealing effect on donor-acceptor interface and its impact on the performance of organic photovoltaic devices based on PSiF-DBT copolymer and C{sub 60}

    SciTech Connect

    Marchiori, Cleber F. N.; Yamamoto, Natasha A. D.; Koehler, Marlus; Roman, Lucimara S.; Matos, Carolina F.; Zarbin, Aldo J. G.; Kujala, Jiri; Tuomisto, Filip; Macedo, Andréia G.

    2015-03-30

    In this work, poly[2,7-(9,9-bis(2-ethylhexyl)-dibenzosilole)-alt-4,7-bis(thiophen-2-yl) benzo-2,1,3-thiadiazole] (PSiF-DBT) was used as active layer in bilayer solar cell with C{sub 60} as electron acceptor. As cast devices already show reasonable power conversion efficiency (PCE) that increases to 4% upon annealing at 100 °C. Space charge limited measurements of the hole mobility (μ) in PSiF-DBT give μ ∼ 1.0 × 10{sup −4} cm{sup 2}/(V s) which does not depend on the temperature of the annealing treatment. Moreover, positron annihilation spectroscopy experiments revealed that PSiF-DBT films are well stacked even without the thermal treatment. The variations in the transport of holes upon annealing are then small. As a consequence, the PCE rise was mainly induced by the increase of the polymer surface roughness that leads to a more effective interface for exciton dissociation at the PSiF-DBT/fullerene heterojunction.

  18. Inclusion compounds of dibenzylthiourea with hydroxypropylated-cyclodextrins for corrosion protection of carbon steel in acidic medium

    NASA Astrophysics Data System (ADS)

    de Souza, Thais M.; Cordeiro, Renata F. B.; Viana, Gil M.; Aguiar, Lucia C. S.; de Senna, Lilian F.; Malta, Luiz Fernando B.; D'Elia, Eliane

    2016-12-01

    In this work the complexation of the guest molecule (dibenzylthiourea-DBT) with α and β forms of hydroxypropylated cyclodextrins was evaluated in solution and in the solid state by different techniques. It was shown that the inclusion complexes were obtained and the aromatic moieties of DBT are points of interaction in the structure of the guest. The inhibitory action of these inclusion compounds in carbon steel corrosion in acidic medium was evaluated by polarization curves, electrochemical impedance diagrams and weight loss measurements. There is an enhancement of the inhibitory action against the carbon steel corrosion in HCl solution when the DBT was encapsulated in inclusion compounds whereas the alone hydroxypropylated cyclodextrins did not present an inhibitory effect. It was concluded that these inclusion compounds could be a good alternative to introduce molecules with low solubility in aqueous media and still increase their inhibitory action.

  19. Second generation anthropomorphic physical phantom for mammography and DBT: Incorporating voxelized 3D printing and inkjet printing of iodinated lesion inserts

    NASA Astrophysics Data System (ADS)

    Sikaria, Dhiraj; Musinsky, Stephanie; Sturgeon, Gregory M.; Solomon, Justin; Diao, Andrew; Gehm, Michael E.; Samei, Ehsan; Glick, Stephen J.; Lo, Joseph Y.

    2016-03-01

    Physical phantoms are needed for the evaluation and optimization of new digital breast tomosynthesis (DBT) systems. Previously, we developed an anthropomorphic phantom based on human subject breast CT data and fabricated using commercial 3D printing. We now present three key advancements: voxelized 3D printing, photopolymer material doping, and 2D inkjet printing of lesion inserts. First, we bypassed the printer's control software in order to print in voxelized form instead of conventional STL surfaces, thus improving resolution and allowing dithering to mix the two photopolymer materials into arbitrary proportions. We demonstrated ability to print details as small as 150μm, and dithering to combine VeroWhitePlus and TangoPlus in 10% increments. Second, to address the limited attenuation difference among commercial photopolymers, we evaluated a beta sample from Stratasys with increased TiO2 doping concentration up to 2.5%, which corresponded to 98% breast density. By spanning 36% to 98% breast density, this doubles our previous contrast. Third, using inkjet printers modified to print with iopamidol, we created 2D lesion patterns on paper that can be sandwiched into the phantom. Inkjet printing has advantages of being inexpensive and easy, and more contrast can be delivered through overprinting. Printing resolution was maintained at 210 μm horizontally and 330 μm vertically even after 10 overprints. Contrast increased linearly with overprinting at 0.7% per overprint. Together, these three new features provide the basis for creating a new anthropomorphic physical breast phantom with improved resolution and contrast, as well as the ability to insert 2D lesions for task-based assessment of performance.

  20. Full Field Digital Mammography (FFDM) versus CMOS Technology, Specimen Radiography System (SRS) and Tomosynthesis (DBT) - Which System Can Optimise Surgical Therapy?

    PubMed

    Schulz-Wendtland, R; Dilbat, G; Bani, M; Fasching, P A; Heusinger, K; Lux, M P; Loehberg, C R; Brehm, B; Hammon, M; Saake, M; Dankerl, P; Jud, S M; Rauh, C; Bayer, C M; Beckmann, M W; Uder, M; Meier-Meitinger, M

    2013-05-01

    Aim: This prospective clinical study aimed to evaluate whether it would be possible to reduce the rate of re-excisions using CMOS technology, a specimen radiography system (SRS) or digital breast tomosynthesis (DBT) compared to a conventional full field digital mammography (FFDM) system. Material and Method: Between 12/2012 and 2/2013 50 patients were diagnosed with invasive breast cancer (BI-RADS™ 5). After histological verification, all patients underwent breast-conserving therapy with intraoperative imaging using 4 different systems and differing magnifications: 1. Inspiration™ (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 lp/mm; 2. BioVision™ (Bioptics, Tucson, AZ, USA), CMOS technology, photodiode array, flat panel, tungsten source, focus 0.05, resolution 50 µm pixel pitch, 12 lp/mm; 3. the Trident™ specimen radiography system (SRS) (Hologic, Bedford, MA, USA), amorphous selenium, tungsten source, focus 0.05, resolution 70 µm pixel pitch, 7.1 lp/mm; 4. tomosynthesis (Siemens, Erlangen, Germany), amorphous selenium, tungsten source, focus 0.1 mm, resolution 85 µm pixel pitch, 8 lp/mm, angular range 50 degrees, 25 projections, scan time > 20 s, geometry: uniform scanning, reconstruction: filtered back projection. The 600 radiographs were prospectively shown to 3 radiologists. Results: Of the 50 patients with histologically proven breast cancer (BI-RADS™ 6), 39 patients required no further surgical therapy (re-excision) after breast-conserving surgery. A retrospective analysis (n = 11) showed a significant (p < 0.05) increase of sensitivity with the BioVision™, the Trident™ and tomosynthesis compared to the Inspiration™ at a magnification of 1.0 : 2.0 or 1.0 : 1.0 (tomosynthesis) (2.6, 3.3 or 3.6 %), i.e. re-excision would not have been necessary in 2, 3 or 4 patients, respectively, compared to findings obtained with a standard

  1. Dialectical Behavioral Therapy for Adolescents (DBT-A): a clinical Trial for Patients with suicidal and self-injurious Behavior and Borderline Symptoms with a one-year Follow-up

    PubMed Central

    2011-01-01

    Background To date, there are no empirically validated treatments of good quality for adolescents showing suicidality and non-suicidal self-injurious behavior. Risk factors for suicide are impulsive and non-suicidal self-injurious behavior, depression, conduct disorders and child abuse. Behind this background, we tested the main hypothesis of our study; that Dialectical Behavioral Therapy for Adolescents is an effective treatment for these patients. Methods Dialectical Behavioral Therapy (DBT) has been developed by Marsha Linehan - especially for the outpatient treatment of chronically non-suicidal patients diagnosed with borderline personality disorder. The modified version of DBT for Adolescents (DBT-A) from Rathus & Miller has been adapted for a 16-24 week outpatient treatment in the German-speaking area by our group. The efficacy of treatment was measured by a pre-/post- comparison and a one-year follow-up with the aid of standardized instruments (SCL-90-R, CBCL, YSR, ILC, CGI). Results In the pilot study, 12 adolescents were treated. At the beginning of therapy, 83% of patients fulfilled five or more DSM-IV criteria for borderline personality disorder. From the beginning of therapy to one year after its end, the mean value of these diagnostic criteria decreased significantly from 5.8 to 2.75. 75% of patients were kept in therapy. For the behavioral domains according to the SCL-90-R and YSR, we have found effect sizes between 0.54 and 2.14. During treatment, non-suicidal self-injurious behavior reduced significantly. Before the start of therapy, 8 of 12 patients had attempted suicide at least once. There were neither suicidal attempts during treatment with DBT-A nor at the one-year follow-up. Conclusions The promising results suggest that the interventions were well accepted by the patients and their families, and were associated with improvement in multiple domains including suicidality, non-suicidal self-injurious behavior, emotion dysregulation and

  2. Effect of omega-3 polyunsaturated fatty acid treatment over mechanical allodynia and depressive-like behavior associated with experimental diabetes.

    PubMed

    Redivo, Daiany D B; Schreiber, Anne K; Adami, Eliana R; Ribeiro, Deidiane E; Joca, Samia R L; Zanoveli, Janaína M; Cunha, Joice M

    2016-02-01

    Neuropathic pain and depression are very common comorbidities in diabetic patients. As the pathophysiological mechanisms are very complex and multifactorial, current treatments are only symptomatic and often worsen the glucose control. Thus, the search for more effective treatments are extremely urgent. In this way, we aimed to investigate the effect of chronic treatment with fish oil (FO), a source of omega-3 polyunsaturated fatty acid, over the mechanical allodynia and in depressive-like behaviors in streptozotocin-diabetic rats. It was observed that the diabetic (DBT) animals, when compared to normoglycemic (NGL) animals, developed a significant mechanical allodynia since the second week after diabetes induction, peaking at fourth week which is completely prevented by FO treatment (0.5, 1 or 3g/kg). Moreover, DBT animals showed an increase of immobility frequency and a decrease of swimming and climbing frequencies in modified forced swimming test (MFST) since the second week after diabetes injection, lasting up at the 4th week. FO treatment (only at a dose of 3g/kg) significantly decreased the immobility frequency and increased the swimming frequency, but did not induce significant changes in the climbing frequency in DBT rats. Moreover, it was observed that DBT animals had significantly lower levels of BDNF in both hippocampus and pre frontal cortex when compared to NGL rats, which is completely prevented by FO treatment. In conclusion, our study demonstrates that FO treatment was able to prevent the mechanical allodynia and the depressive-like behaviors in DBT rats, which seems to be related to its capacity of BDNF level restoration.

  3. Applications of micellar enzymology to clean coal technology. [Laccase

    SciTech Connect

    Walsh, C.T.

    1990-04-27

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies.

  4. Applications of micellar enzymology to clean coal technology

    SciTech Connect

    Walsh, C.T.

    1990-01-20

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid Dibenzothiophene (DBT) and ehtylphenylsulfide (EPS)are serving as serving as models of organic sulfur-containing components of coal in initial studies.

  5. Applications of micellar enzymology to clean coal technology. First quarterly report

    SciTech Connect

    Walsh, C.T.

    1990-01-20

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid Dibenzothiophene (DBT) and ehtylphenylsulfide (EPS)are serving as serving as models of organic sulfur-containing components of coal in initial studies.

  6. Applications of micellar enzymology to clean coal technology. Second quarterly report

    SciTech Connect

    Walsh, C.T.

    1990-04-27

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies.

  7. Preparation, characterization and application in deep catalytic ODS of the mesoporous silica pillared clay incorporated with phosphotungstic acid.

    PubMed

    Li, Baoshan; Liu, Zhenxing; Liu, Jianjun; Zhou, Zhiyuan; Gao, Xiaohui; Pang, Xinmei; Sheng, Huiting

    2011-10-15

    Mesoporous silica pillared clay (SPC) materials with different contents of H(3)PW(12)O(40) (HPW) heteropoly acid were synthesized by introducing HPW into clay interlayer template in an acidic suspension using sol-gel method. Samples with similar HPW loadings were also prepared by impregnation method using SPC as the support. The results of the characterizations showed that HPW was dispersed more homogeneously in the encapsulated samples than in the impregnated samples. The encapsulated materials exhibited better catalytic performance than the impregnated samples in oxidative desulfurization of dibenzothiophene-containing model oil. The sulfur removal reached up to 98.6% for the model oil under the experiential conditions.

  8. Effect of α-Methyl versus α-Hydrogen Substitution on Brain Availability and Tumor Imaging Properties of Heptanoic [F-18]Fluoroalkyl Amino Acids for Positron Emission Tomography (PET).

    PubMed

    Bouhlel, Ahlem; Alyami, Wadha; Li, Aixiao; Yuan, Liya; Rich, Keith; McConathy, Jonathan

    2016-04-14

    Two [(18)F]fluoroalkyl substituted amino acids differing only by the presence or absence of a methyl group on the α-carbon, (S)-2-amino-7-[(18)F]fluoro-2-methylheptanoic acid ((S)-[(18)F]FAMHep, (S)-[(18)F]14) and (S)-2-amino-7-[(18)F]fluoroheptanoic acid ((S)-[(18)F]FAHep, (S)-[(18)F]15), were developed for brain tumor imaging and compared to the well-established system L amino acid tracer, O-(2-[(18)F]fluoroethyl)-l-tyrosine ([(18)F]FET), in the delayed brain tumor (DBT) mouse model of high-grade glioma. Cell uptake, biodistribution, and PET/CT imaging studies showed differences in amino acid transport of these tracer by DBT cells. Recognition of (S)-[(18)F]15 but not (S)-[(18)F]14 by system L amino acid transporters led to approximately 8-10-fold higher uptake of the α-hydrogen substituted analogue (S)-[(18)F]15 in normal brain. (S)-[(18)F]15 had imaging properties similar to those of (S)-[(18)F]FET in the DBT tumor model while (S)-[(18)F]14 afforded higher tumor to brain ratios due to much lower uptake by normal brain. These results have important implications for the future development of α-alkyl and α,α-dialkyl substituted amino acids for brain tumor imaging.

  9. Applications of micellar enzymology to clean coal technology

    SciTech Connect

    Walsh, C.T.

    1990-10-26

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid Dibenzothiophene (DBT) and ethlyphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Among the variables which will be examined are the surfactant, the solvent, the water:surfactant ration and the pH and ionic strength of the aqueous phase. Studies were carried out with HRP, Type I RZ=1.2 and Type VI RZ=3.2 and laccase from Polyporus versicolor. Substrates for HRP assays included hydrogen peroxide, DBT, DBT sulfoxide, and DBT sulfone. Buffers included sodium phosphate. For formation of reverse micelle solutions the surfactant AOT, di(2-ethyl-hexyl)sodium sulphosuccinate, was obtained from Sigma Chemical Co. Isooctant was used as organic solvent. 12 refs., 5 figs., 3 tabs.

  10. DBT in an outpatient forensic setting.

    PubMed

    van den Bosch, L M C; Hysaj, M; Jacobs, P

    2012-01-01

    Literature shows that effective treatment of borderline personality disorder (BPD) has become possible. However, borderline patients in forensic psychiatry do not seem to benefit from this development. In forensic psychiatry, prevention of criminal recidivism is the main focus of treatment, not core borderline problems like parasuicidal and self-destructive behavior. A dialectical behavioral treatment program for BPD was implemented in an outpatient forensic clinic in The Netherlands. Sociodemographic, clinical, and treatment data were collected from ten male, and nineteen female forensic BPD patients, and compared with corresponding data from fifty-eight non-forensic BPD patients. The results show that it is possible to implement dialectical behavior therapy in an outpatient forensic clinic. The data indicate that the exclusion of forensic patients, and especially female forensic patients, from evidence-based treatment is unjustified given the highly comparable clinical and etiological characteristics they share with female BPD patients from general mental health settings.

  11. Tributyltin and triphenyltin inhibit osteoclast differentiation through a retinoic acid receptor-dependent signaling pathway

    SciTech Connect

    Yonezawa, Takayuki; Hasegawa, Shin-ichi; Ahn, Jae-Yong; Cha, Byung-Yoon; Teruya, Toshiaki; Hagiwara, Hiromi; Nagai, Kazuo; Woo, Je-Tae; E-mail: jwoo@isc.chubu.ac.jp

    2007-03-30

    Organotin compounds, such as tributyltin (TBT) and triphenyltin (TPT), have been widely used in agriculture and industry. Although these compounds are known to have many toxic effects, including endocrine-disrupting effects, their effects on bone resorption are unknown. In this study, we investigated the effects of organotin compounds, such as monobutyltin (MBT), dibutyltin (DBT), TBT, and TPT, on osteoclast differentiation using mouse monocytic RAW264.7 cells. MBT and DBT had no effects, whereas TBT and TPT dose-dependently inhibited osteoclast differentiation at concentrations of 3-30 nM. Treatment with a retinoic acid receptor (RAR)-specific antagonist, Ro41-5253, restored the inhibition of osteoclastogenesis by TBT and TPT. TBT and TPT reduced receptor activator of nuclear factor-{kappa}B ligand (RANKL) induced nuclear factor of activated T cells (NFAT) c1 expression, and the reduction in NFATc1 expression was recovered by Ro41-5253. Our results suggest that TBT and TPT suppress osteoclastogenesis by inhibiting RANKL-induced NFATc1 expression via an RAR-dependent signaling pathway.

  12. Applications of micellar enzymology to clean coal technology

    SciTech Connect

    Walsh, C.T.

    1991-01-30

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models or organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Among the variables which will be examined are the surfactant, the solvent, the water:surfactant ratio and the pH and ionic strength of the aqueous phase.

  13. Applications of micellar enzymology to clean coal technology. Ninth quarterly report

    SciTech Connect

    Walsh, C.T.

    1991-01-30

    This project is designed to develop methods for pre-combustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models or organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Among the variables which will be examined are the surfactant, the solvent, the water:surfactant ratio and the pH and ionic strength of the aqueous phase.

  14. Applications of micellar enzymology to clean coal technology

    SciTech Connect

    Walsh, C.T.

    1991-10-21

    This project is designed to develop methods for precombustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid (Figure 1). Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. 12 refs., 2 figs., 7 tabs.

  15. Synthesis, radiolabeling, and biological evaluation of (R)- and (S)-2-amino-5-[18F]fluoro-2-methylpentanoic acid ((R)-, (S)-[18F]FAMPe) as potential positron emission tomography tracers for brain tumors

    DOE PAGES

    Bouhlel, Ahlem; Zhou, Dong; Li, Aixiao; ...

    2015-04-06

    In this paper, a novel 18F-labeled α,α-disubstituted amino acid-based tracer, 2-amino-5-[18F]fluoro-2-methylpentanoic acid ([18F]FAMPe), has been developed for brain tumor imaging with a longer alkyl side chain than previously reported compounds to increase brain availability via system L amino acid transport. Both enantiomers of [18F]FAMPe were obtained in good radiochemical yield (24–52% n = 8) and high radiochemical purity (>99%). In vitro uptake assays in mouse DBT gliomas cells revealed that (S)-[18F]FAMPe enters cells partly via sodium-independent system L transporters and also via other nonsystem A transport systems including transporters that recognize glutamine. Biodistribution and small animal PET/CT studies in themore » mouse DBT model of glioblastoma showed that both (R)- and (S)-[18F]FAMPe have good tumor imaging properties with the (S)-enantiomer providing higher tumor uptake and tumor to brain ratios. Finally, comparison of the SUVs showed that (S)-[18F]FAMPe had higher tumor to brain ratios compared to (S)-[18F]FET, a well-established system L substrate.« less

  16. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae

    SciTech Connect

    Krawiec, S.

    1991-08-30

    The DbtS{sup +} phenotype is defined as the selective ability to oxidize the sulfur in dibenzothiophene (DBT) successively to dibenzothiophene-5-oxide, dibenzosulfone, and, finally, either o, o'-biphenol or monohydroxybiphenyl. By using a fluorescent assay, many Pseudomonas putida isolates having a DbtS{sup +} phenotype have been obtained. The ability of the isolates to generate o, o'-biphenol was confirmed with HPLC shortly after the time of isolation. The broad-host-range plasmid, R68.45, was introduced from P. putida PRS 2003 into many soil isolates. The plasmid was able to mobilize the determinants for the DbtS{sup +} phenotype. Accordingly, R68.45 and the determinants of the phenotype could be transferred simultaneously form soil isolates to P. aeruginosa 27853. The DbtS{sup +} phenotype in the isolates and in P. aeruginosa 27853 has proven to be unstable. Whether the instability is genetic, physiological, some combination of these two, or is founded on some other phenomenon is not known. Fresh Gram-positive isolates with the DbtS{sup +} phenotype have been isolated using the sulfur bioavailability assay. The DbtS{sup +} phenotype in these isolates appears to be stable. The product of desulfurization of DBT of dibenzosulfone is monohydroxybiphenyl. The nature of the endproduct has been confirmed by HPLC, colorimetry, GC/mass spectroscopy, and UV absorption. The kinetics of monohydroxybiphenyl production are being studied in batch and continuous culture. Study of the basis of cloning with R68.45 has continued. Data regarding in vivo cloning with R68.45 will be important when the genetic determinants for the DbtS{sup +} phenotype must be moved from one species to another by natural processes'' rather than through methods of genetic engineering. 8 refs., 3 figs.

  17. Synthesis, radiolabeling, and biological evaluation of (R)- and (S)-2-amino-5-[18F]fluoro-2-methylpentanoic acid ((R)-, (S)-[18F]FAMPe) as potential positron emission tomography tracers for brain tumors

    SciTech Connect

    Bouhlel, Ahlem; Zhou, Dong; Li, Aixiao; Yuan, Liya; Rich, Keith M.; McConathy, Jonathan

    2015-04-06

    In this paper, a novel 18F-labeled α,α-disubstituted amino acid-based tracer, 2-amino-5-[18F]fluoro-2-methylpentanoic acid ([18F]FAMPe), has been developed for brain tumor imaging with a longer alkyl side chain than previously reported compounds to increase brain availability via system L amino acid transport. Both enantiomers of [18F]FAMPe were obtained in good radiochemical yield (24–52% n = 8) and high radiochemical purity (>99%). In vitro uptake assays in mouse DBT gliomas cells revealed that (S)-[18F]FAMPe enters cells partly via sodium-independent system L transporters and also via other nonsystem A transport systems including transporters that recognize glutamine. Biodistribution and small animal PET/CT studies in the mouse DBT model of glioblastoma showed that both (R)- and (S)-[18F]FAMPe have good tumor imaging properties with the (S)-enantiomer providing higher tumor uptake and tumor to brain ratios. Finally, comparison of the SUVs showed that (S)-[18F]FAMPe had higher tumor to brain ratios compared to (S)-[18F]FET, a well-established system L substrate.

  18. Improvement of biodesulfurization rate by assembling nanosorbents on the surfaces of microbial cells.

    PubMed

    Guobin, S; Huaiying, Z; Weiquan, C; Jianmin, X; Huizhou, L

    2005-12-01

    To improve biodesulfurization rate is a key to industrialize biodesulfurization technology. The biodesulfurization rate is partially affected by transfer rate of substrates from organic phase to microbial cell. In this study, gamma-Al2O3 nanosorbents, which had the ability to selectively adsorb dibenzothiophene (DBT) from organic phase, were assembled on the surfaces of Pseudomonas delafieldii R-8 cell, a desulfurization strain. gamma-Al2O3 nanosorbents have the ability to adsorb DBT from oil phase, and the rate of adsorption was far higher than that of biodesulfurization. Thus, DBT can be quickly transferred to the biocatalyst surface where nanosorbents were located, which quickened DBT transfer from organic phase to biocatalyst surface and resulted in the increase of biodesulfurization rate. The desulfurization rate of the cells assembled with nanosorbents was approximately twofold higher than that of original cells. The cells assembled with nanosorbents were observed by a transmission electron microscope.

  19. Rectal temperature responses of donkeys administered with ascorbic acid and subjected to load carrying (packing) during the harmattan season in Nigeria.

    PubMed

    Olaifa, Folashade; Ayo, Joseph Olusegun; Ambali, Suleiman Folorunsho; Rekwot, Peter Ibrahim; Minka, Ndazo Salka

    2013-02-01

    The aim of the experiment was to evaluate the effect of 4-h load carrying (packing) on donkeys administered with ascorbic acid (AA) during the harmattan season. Six donkeys administered orally with ascorbic acid (200 mg/kg) and subjected to packing served as experimental animals, while six others given only distilled water served as control animals. The rectal temperature (RT) of each donkey and dry-bulb temperature (DBT) and relative humidity (RH) of the research pen were recorded at 0600 hours pre-packing; while post-packing, the values were obtained at 1430, 1600 and 1800 hours. The DBT values (ranges) recorded before, during and after packing were 13.7 ± 1.3 °C (11-15 °C), 28.4 ± 1.0 °C (22.7-30.3 °C) and 30.6 ± 3.0 °C (19.8-45 °C), respectively. The highest temperature-humidity index (THI) of 83.4 ± 6.9 was obtained at 1430 hours after packing, and the value decreased to 64.2 ± 5.8 at 1800 hours. The thermal environmental conditions were outside the thermoneutral zone for the donkeys. The RT values recorded immediately after packing did not differ (P > 0.05) in experimental and control donkeys; but at 1600 and 1800 hours, values obtained in control donkeys (38.48 ± 0.12 and 38.12 ± 0.12 °C, respectively) were significantly higher (P < 0.05) than those recorded in experimental donkeys (38.16 ± 0.14 and 37.85 ± 0.14 °C, respectively). In conclusion, administration of ascorbic acid reduced the rise in RT due to packing and may be of value in the amelioration of adverse effects of heat stress associated with work in donkeys.

  20. Biocatalytic desulfurization of thiophenic compounds and crude oil by newly isolated bacteria.

    PubMed

    Mohamed, Magdy El-Said; Al-Yacoub, Zakariya H; Vedakumar, John V

    2015-01-01

    Microorganisms possess enormous highly specific metabolic activities, which enable them to utilize and transform nearly every known chemical class present in crude oil. In this context, one of the most studied biocatalytic processes is the biodesulfurization (BDS) of thiophenic sulfur-containing compounds such as benzothiophene (BT) and dibenzothiophene (DBT) in crude oils and refinery streams. Three newly isolated bacterial strains, which were affiliated as Rhodococcus sp. strain SA11, Stenotrophomonas sp. strain SA21, and Rhodococcus sp. strain SA31, were enriched from oil contaminated soil in the presence of DBT as the sole S source. GC-FID analysis of DBT-grown cultures showed consumption of DBT, transient formation of DBT sulfone (DBTO2) and accumulation of 2-hydroxybiphenyl (2-HBP). Molecular detection of the plasmid-borne dsz operon, which codes for the DBT desulfurization activity, revealed the presence of dszA, dszB, and dszC genes. These results point to the operation of the known 4S pathway in the BDS of DBT. The maximum consumption rate of DBT was 11 μmol/g dry cell weight (DCW)/h and the maximum formation rate of 2-HBP formation was 4 μmol/g DCW/h. Inhibition of both cell growth and DBT consumption by 2-HBP was observed for all isolates but SA11 isolate was the least affected. The isolated biocatalysts desulfurized other model DBT alkylated homologs. SA11 isolate was capable of desulfurizing BT as well. Resting cells of SA11 exhibited 10% reduction in total sulfur present in heavy crude oil and 18% reduction in total sulfur present in the hexane-soluble fraction of the heavy crude oil. The capabilities of the isolated bacteria to survive and desulfurize a wide range of S compounds present in crude oil are desirable traits for the development of a robust BDS biocatalyst to upgrade crude oils and refinery streams.

  1. Enzymatic desulfurization of coal. Second quarterly report, October 1--December 15, 1988

    SciTech Connect

    Marquis, J.K.; Kitchell, J.P.

    1988-12-15

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes or commercially available enzymes. Our work is focused on the treatment of ``model`` organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  2. Enzymatic desulfurization of coal

    SciTech Connect

    Marquis, J.K. . School of Medicine); Kitchell, J.P. )

    1988-12-15

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes or commercially available enzymes. Our work is focused on the treatment of model'' organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  3. Enzymatic desulfurization of coal. Fourth quarterly report, March 16--June 15, 1989

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V.; Marquis, J.K.

    1989-06-16

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes as well as commercially available enzymes. Our work is focused on the treatment of ``model`` organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  4. Enzymatic desulfurization of coal

    SciTech Connect

    Boyer, Y.N.; Crooker, S.C.; Kitchell, J.P.; Nochur, S.V. ); Marquis, J.K. . School of Medicine)

    1989-06-16

    Our current efforts to develop clean coal technology emphasize the advantages of enzymatic desulfurization techniques and have specifically addressed the potential of using partially-purified extracellular microbial enzymes as well as commercially available enzymes. Our work is focused on the treatment of model'' organic sulfur compounds such as dibenzothiophene (DBT) and ethylphenylsulfide (EPS). Furthermore, we are designing experiments to facilitate the enzymatic process by means of a hydrated organic solvent matrix.

  5. Aspartic acid

    MedlinePlus

    ... also called asparaginic acid. Aspartic acid helps every cell in the body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources of aspartic acid include: Legumes such as ...

  6. Folic Acid

    MedlinePlus

    Folic acid is a B vitamin. It helps the body make healthy new cells. Everyone needs folic acid. For women who may get pregnant, it is really important. Getting enough folic acid before and during pregnancy can prevent major birth ...

  7. Folic Acid

    MedlinePlus

    Folic acid is used to treat or prevent folic acid deficiency. It is a B-complex vitamin needed by ... Folic acid comes in tablets. It usually is taken once a day. Follow the directions on your prescription label ...

  8. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1995-01-01

    Although acid rain is fading as a political issue in the United States and funds for research in this area have largely disappeared, the acidity of rain in the Eastern United States has not changed significantly over the last decade, and it continues to be a serious environmental problem. Acid deposition (commonly called acid rain) is a term applied to all forms of atmospheric deposition of acidic substances - rain, snow, fog, acidic dry particulates, aerosols, and acid-forming gases. Water in the atmosphere reacts with certain atmospheric gases to become acidic. For example, water reacts with carbon dioxide in the atmosphere to produce a solution with a pH of about 5.6. Gases that produce acids in the presence of water in the atmosphere include carbon dioxide (which converts to carbonic acid), oxides of sulfur and nitrogen (which convert to sulfuric and nitric acids}, and hydrogen chloride (which converts to hydrochloric acid). These acid-producing gases are released to the atmosphere through natural processes, such as volcanic emissions, lightning, forest fires, and decay of organic matter. Accordingly, precipitation is slightly acidic, with a pH of 5.0 to 5.7 even in undeveloped areas. In industrialized areas, most of the acid-producing gases are released to the atmosphere from burning fossil fuels. Major emitters of acid-producing gases include power plants, industrial operations, and motor vehicles. Acid-producing gases can be transported through the atmosphere for hundreds of miles before being converted to acids and deposited as acid rain. Because acids tend to build up in the atmosphere between storms, the most acidic rain falls at the beginning of a storm, and as the rain continues, the acids "wash out" of the atmosphere.

  9. Acid Rain.

    ERIC Educational Resources Information Center

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  10. Arene Binding Affinities in [CpRu(nu6-arene)]+ Complexes: Models for the Adsorption of Arenes on Hydroesulferization Catalysts

    SciTech Connect

    Choi, M. G.; Ho, T. C.; Angelici, R.

    2008-02-29

    Product/reactant ratios (Y) were determined for the reactions CpRu({eta}{sup 6}-DBT){sup +} + L CpRu({eta}{sup 6}-L){sup +} + DBT (where DBT is dibenzothiophene and L is a homo- or heterocyclic arene), which were conducted under UV photolysis conditions. In the photostationary state, the Y values for the different arenes decrease in the following order: mesitylene (17) > toluene (13) > indole (9.1) > carbazole (6.7) > benzene (5.9) > fluorene (5.1) > biphenyl (3.9) > DBT (1.0) > phenanthrene (0.65) > naphthalene (0.35). In general, alkyl-substituted arenes have a higher binding affinity than the parent arene, except for tert-butyl groups, which decrease the Y values. These trends in {eta}{sup 6}-arene binding to CpRu{sup +} provide a basis for understanding competitive adsorption of arenes on metal sites of hydrotreating catalysts. Such arene components in petroleum feedstocks reduce the rates of hydrodesulfurization of dibenzothiophenes.

  11. Obeticholic Acid

    MedlinePlus

    Obeticholic acid is used alone or in combination with ursodiol (Actigall, Urso) to treat primary biliary cholangitis (PBC; a ... were not treated successfully with ursodiol alone. Obeticholic acid is in a class of medications called farnesoid ...

  12. Aminocaproic Acid

    MedlinePlus

    Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

  13. Acid mucopolysaccharides

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003368.htm Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  14. Aristolochic Acids

    MedlinePlus

    ... Sciences NIH-HHS www.niehs.nih.gov Aristolochic Acids Key Points Report on Carcinogens Status Known to be human carcinogens Aristolochia Clematitis Aristolochic Acids n Known human carcinogens n Found in certain ...

  15. Ascorbic Acid

    MedlinePlus

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  16. Ethacrynic Acid

    MedlinePlus

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  17. Amino acids

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  18. Valproic Acid

    MedlinePlus

    Valproic acid is used alone or with other medications to treat certain types of seizures. Valproic acid is also used to treat mania (episodes of ... to relieve headaches that have already begun. Valproic acid is in a class of medications called anticonvulsants. ...

  19. Tailoring Silica-alumina Supported Pt-Pd As Poison Tolerant Catalyst For Aromatics Hydrogenation

    SciTech Connect

    Yu, Yanzhe; Gutierrez, Oliver Y.; Haller, Gary L.; Colby, Robert J.; Kabius, Bernd C.; Rob van Veen, J. A.; Jentys, Andreas; Lercher, Johannes A.

    2013-08-01

    The tailoring of the physicochemical and catalytic properties of mono- and bimetallic Pt-Pd catalysts supported on amorphous silica-alumina is studied. Electron energy loss spectroscopy and extended X-ray absorption fine structure analyses indicated that bimetallic Pt-Pd and relatively large monometallic Pd particles were formed, whereas the X-ray absorption near edge structure provided direct evidence for the electronic deficiency of the Pt atoms. The heterogeneous distribution of metal particles was also shown by high resolution transmission electron microscopy. The average structure of the bimetallic particles (Pt-rich core and Pd-rich shell) and the presence of Pd particles led to surface Pd enrichment, which was independently shown by IR spectra of adsorbed CO. The specific metal distribution, average size, and surface composition of the Pt-Pd particles depend to a large extent on the metal precursors. In the presence of NH3 ligands, Pt-Pd particles with a fairly homogeneous bulk and surface metal distribution were formed. Also high Lewis acid site concentration of the carrier leads to more homogeneous bimetallic particles. All catalysts were active for the hydrogenation of tetralin in the absence and presence of quinoline and dibenzothiophene (DBT). Monometallic Pt catalysts had the highest hydrogenation activity in poison-free and quinoline-containing feed. When DBT was present, bimetallic Pt-Pd catalysts with the most homogenous metal distribution showed the highest activity. The higher resistance of bimetallic catalysts towards sulfur poisoning compared to their monometallic Pt counterparts results from the weakened metal-sulfur bond on the electron deficient Pt atoms. Thus, increasing the fraction of electron deficient Pt on the surface of the bimetallic particles increases the efficiency of the catalyst in the presence of sulfur.

  20. The hydrocarbon-degrading marine bacterium Cobetia sp. strain MM1IDA2H-1 produces a biosurfactant that interferes with quorum sensing of fish pathogens by signal hijacking.

    PubMed

    Ibacache-Quiroga, C; Ojeda, J; Espinoza-Vergara, G; Olivero, P; Cuellar, M; Dinamarca, M A

    2013-07-01

    Biosurfactants are produced by hydrocarbon-degrading marine bacteria in response to the presence of water-insoluble hydrocarbons. This is believed to facilitate the uptake of hydrocarbons by bacteria. However, these diffusible amphiphilic surface-active molecules are involved in several other biological functions such as microbial competition and intra- or inter-species communication. We report the isolation and characterization of a marine bacterial strain identified as Cobetia sp. MM1IDA2H-1, which can grow using the sulfur-containing heterocyclic aromatic hydrocarbon dibenzothiophene (DBT). As with DBT, when the isolated strain is grown in the presence of a microbial competitor, it produces a biosurfactant. Because the obtained biosurfactant was formed by hydroxy fatty acids and extracellular lipidic structures were observed during bacterial growth, we investigated whether the biosurfactant at its critical micelle concentration can interfere with bacterial communication systems such as quorum sensing. We focused on Aeromonas salmonicida subsp. salmonicida, a fish pathogen whose virulence relies on quorum sensing signals. Using biosensors for quorum sensing based on Chromobacterium violaceum and Vibrio anguillarum, we showed that when the purified biosurfactant was mixed with N-acyl homoserine lactones produced by A. salmonicida, quorum sensing was inhibited, although bacterial growth was not affected. In addition, the transcriptional activities of A. salmonicida virulence genes that are controlled by quorum sensing were repressed by both the purified biosurfactant and the growth in the presence of Cobetia sp. MM1IDA2H-1. We propose that the biosurfactant, or the lipid structures interact with the N-acyl homoserine lactones, inhibiting their function. This could be used as a strategy to interfere with the quorum sensing systems of bacterial fish pathogens, which represents an attractive alternative to classical antimicrobial therapies in fish aquaculture.

  1. The hydrocarbon-degrading marine bacterium Cobetia sp. strain MM1IDA2H-1 produces a biosurfactant that interferes with quorum sensing of fish pathogens by signal hijacking

    PubMed Central

    Ibacache-Quiroga, C; Ojeda, J; Espinoza-Vergara, G; Olivero, P; Cuellar, M; Dinamarca, M A

    2013-01-01

    Summary Biosurfactants are produced by hydrocarbon-degrading marine bacteria in response to the presence of water-insoluble hydrocarbons. This is believed to facilitate the uptake of hydrocarbons by bacteria. However, these diffusible amphiphilic surface-active molecules are involved in several other biological functions such as microbial competition and intra-or inter-species communication. We report the isolation and characterization of a marine bacterial strain identified as Cobetia sp. MM1IDA2H-1, which can grow using the sulfur-containing heterocyclic aromatic hydrocarbon dibenzothiophene (DBT). As with DBT, when the isolated strain is grown in the presence of a microbial competitor, it produces a biosurfactant. Because the obtained biosurfactant was formed by hydroxy fatty acids and extracellular lipidic structures were observed during bacterial growth, we investigated whether the biosurfactant at its critical micelle concentration can interfere with bacterial communication systems such as quorum sensing. We focused on Aeromonas salmonicida subsp. salmonicida, a fish pathogen whose virulence relies on quorum sensing signals. Using biosensors for quorum sensing based on Chromobacterium violaceum and Vibrio anguillarum, we showed that when the purified biosurfactant was mixed with N-acyl homoserine lactones produced by A. salmonicida, quorum sensing was inhibited, although bacterial growth was not affected. In addition, the transcriptional activities of A. salmonicida virulence genes that are controlled by quorum sensing were repressed by both the purified biosurfactant and the growth in the presence of Cobetia sp. MM1IDA2H-1. We propose that the biosurfactant, or the lipid structures interact with the N-acyl homoserine lactones, inhibiting their function. This could be used as a strategy to interfere with the quorum sensing systems of bacterial fish pathogens, which represents an attractive alternative to classical antimicrobial therapies in fish

  2. Fatty acids - trans fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  3. Sulfur source-mediated transcriptional regulation of the rhlABC genes involved in biosurfactants production by Pseudomonas sp. strain AK6U

    PubMed Central

    Ismail, Wael; El Nayal, Ashraf M.; Ramadan, Ahmed R.; Abotalib, Nasser

    2014-01-01

    Despite the nutritional significance of sulfur, its influence on biosurfactants production has not been sufficiently studied. We investigated the expression of key biosurfactants production genes, rhlABC, in cultures of Pseudomonas sp. AK6U grown with inorganic or organic sulfur sources. AK6U grew with either inorganic sulfate (MgSO4), dibenzothiophene (DBT), or DBT-sulfone as a sole sulfur source in the presence of glucose as a carbon source. The AK6U cultures produced variable amounts of biosurfactants depending on the utilized sulfur source. Biosurfactants production profile of the DBT cultures was significantly different from that of the DBT-sulfone and inorganic sulfate cultures. The last two cultures were very similar in terms of biosurfactants productivity. Biosurfactants yield in the DBT cultures (1.3 g/L) was higher than that produced by the DBT-sulfone (0.5 g/L) and the inorganic sulfate (0.44 g/L) cultures. Moreover, the surface tension reduction in the DBT cultures (33 mN/m) was much stronger than that measured in the DBT-sulfone (58 mN/m) or inorganic sulfate (54 mN/m) cultures. RT-qPCR revealed variations in the expression levels of the rhlABC genes depending on the sulfur source. The DBT cultures had higher expression levels for the three genes as compared to the DBT-sulfone and inorganic sulfate cultures. There was no significant difference in the expression profiles between the DBT-sulfone and the MgSO4 cultures. The increased expression of rhlC in the DBT cultures is indicative for production of higher amounts of dirhamnolipids compared to the DBT-sulfone and inorganic sulfate cultures. The gene expression results were in good agreement with the biosurfactants production yields and surface tension measurements. The sulfur source mediates a fine-tuned mechanism of transcriptional regulation of biosurfactants production genes. Our findings can have an impact on industrial production of biosurfactants and other biotechnological processes like

  4. Sulfur source-mediated transcriptional regulation of the rhlABC genes involved in biosurfactants production by Pseudomonas sp. strain AK6U.

    PubMed

    Ismail, Wael; El Nayal, Ashraf M; Ramadan, Ahmed R; Abotalib, Nasser

    2014-01-01

    Despite the nutritional significance of sulfur, its influence on biosurfactants production has not been sufficiently studied. We investigated the expression of key biosurfactants production genes, rhlABC, in cultures of Pseudomonas sp. AK6U grown with inorganic or organic sulfur sources. AK6U grew with either inorganic sulfate (MgSO4), dibenzothiophene (DBT), or DBT-sulfone as a sole sulfur source in the presence of glucose as a carbon source. The AK6U cultures produced variable amounts of biosurfactants depending on the utilized sulfur source. Biosurfactants production profile of the DBT cultures was significantly different from that of the DBT-sulfone and inorganic sulfate cultures. The last two cultures were very similar in terms of biosurfactants productivity. Biosurfactants yield in the DBT cultures (1.3 g/L) was higher than that produced by the DBT-sulfone (0.5 g/L) and the inorganic sulfate (0.44 g/L) cultures. Moreover, the surface tension reduction in the DBT cultures (33 mN/m) was much stronger than that measured in the DBT-sulfone (58 mN/m) or inorganic sulfate (54 mN/m) cultures. RT-qPCR revealed variations in the expression levels of the rhlABC genes depending on the sulfur source. The DBT cultures had higher expression levels for the three genes as compared to the DBT-sulfone and inorganic sulfate cultures. There was no significant difference in the expression profiles between the DBT-sulfone and the MgSO4 cultures. The increased expression of rhlC in the DBT cultures is indicative for production of higher amounts of dirhamnolipids compared to the DBT-sulfone and inorganic sulfate cultures. The gene expression results were in good agreement with the biosurfactants production yields and surface tension measurements. The sulfur source mediates a fine-tuned mechanism of transcriptional regulation of biosurfactants production genes. Our findings can have an impact on industrial production of biosurfactants and other biotechnological processes like

  5. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

    This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

  6. Asparagusic acid.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2014-01-01

    Asparagusic acid (1,2-dithiolane-4-carboxylic acid) is a simple sulphur-containing 5-membered heterocyclic compound that appears unique to asparagus, though other dithiolane derivatives have been identified in non-food species. This molecule, apparently innocuous toxicologically to man, is the most probable culprit responsible for the curious excretion of odorous urine following asparagus ingestion. The presence of the two adjacent sulphur atoms leads to an enhanced chemical reactivity, endowing it with biological properties including the ability to substitute potentially for α-lipoic acid in α-keto-acid oxidation systems. This brief review collects the scattered data available in the literature concerning asparagusic acid and highlights its properties, intermediary metabolism and exploratory applications.

  7. Acid rain

    SciTech Connect

    Sweet, W.

    1980-06-20

    Acid precipitation includes not only rain but also acidified snow, hail and frost, as well as sulfur and nitrogen dust. The principal source of acid precipitation is pollution emitted by power plants and smelters. Sulfur and nitrogen compounds contained in the emissions combine with moisture to form droplets with a high acid content - sometimes as acidic as vinegar. When sufficiently concentrated, these acids can kill fish and damage material structures. Under certain circumstances they may reduce crop and forest yields and cause or aggravate respiratory diseases in humans. During the summer, especially, pollutants tend to collect over the Great Lakes in high pressure systems. Since winds typically are westerly and rotate clockwise around high pressure systems, the pollutants gradually are dispersed throughout the eastern part of the continent.

  8. Applications of micellar enzymology to clean coal technology

    SciTech Connect

    Walsh, C.T.

    1993-03-09

    This project is designed to develop methods for precombustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Studies by several groups (Martinek et al., 1981; Kabanov et al., 1988; Martinek, 1989; Verhaert et al., 1990) have shown that the surfactant AOT over a broad concentration range in organic solvents produces micelles, comparatively uniform in diameter, which incorporate hydrophilic enzymes. The activity (kcat) of certain enzymes in this system is higher than in aqueous solution. This surfactant is therefore being examined as a vehicle for enhancement of sulfoxidation reactions.

  9. Applications of micellar enzymology to clean coal technology. Twelfth quarterly report

    SciTech Connect

    Walsh, C.T.

    1993-03-09

    This project is designed to develop methods for precombustion coal remediation by implementing recent advances in enzyme biochemistry. The novel approach of this study is incorporation of hydrophilic oxidative enzymes in reverse micelles in an organic solvent. Enzymes from commercial sources or microbial extracts are being investigated for their capacity to remove organic sulfur from coal by oxidation of the sulfur groups, splitting of C-S bonds and loss of sulfur as sulfuric acid. Dibenzothiophene (DBT) and ethylphenylsulfide (EPS) are serving as models of organic sulfur-containing components of coal in initial studies. A goal of this project is to define a reverse micelle system that optimizes the catalytic activity of enzymes toward desulfurization of model compounds and ultimately coal samples. Studies by several groups (Martinek et al., 1981; Kabanov et al., 1988; Martinek, 1989; Verhaert et al., 1990) have shown that the surfactant AOT over a broad concentration range in organic solvents produces micelles, comparatively uniform in diameter, which incorporate hydrophilic enzymes. The activity (kcat) of certain enzymes in this system is higher than in aqueous solution. This surfactant is therefore being examined as a vehicle for enhancement of sulfoxidation reactions.

  10. Acid fog

    SciTech Connect

    Hileman, B.

    1983-03-01

    Fog in areas of southern California previously thought to be pollution-free has been shown to have a pH as low as 1.69. It has been found to be most acidic after smoggy days, suggesting that it forms on the aerosol associated with the previously exiting smog. Studies on Whiteface Mountain in the Adirondacks show that fog water is often 10 times as acidic as rainwater. As a result of their studies, California plans to spend $4 million on acid deposition research in the coming year. (JMT)

  11. Mefenamic Acid

    MedlinePlus

    ... as mefenamic acid may cause ulcers, bleeding, or holes in the stomach or intestine. These problems may ... like coffee grounds, blood in the stool, or black and tarry stools.Keep all appointments with your ...

  12. Acid Rain

    MedlinePlus

    ... EPA Is Doing Acid Rain Program Cross-State Air Pollution Rule Progress Reports Educational Resources Kid's Site for ... Monitoring National Atmospheric Deposition Program (NADP) Exit Interstate Air Pollution Transport Contact Us to ask a question, provide ...

  13. Folic Acid

    MedlinePlus

    ... folic acid can hide signs that you lack vitamin B12, which can cause nerve damage. 10 Do I ... Rosenberg, I.H., et al. (2007). Folate and vitamin B12 status in relation to anemia, macrocytosis and cognitive ...

  14. Acid Precipitation

    ERIC Educational Resources Information Center

    Likens, Gene E.

    1976-01-01

    Discusses the fact that the acidity of rain and snow falling on parts of the U.S. and Europe has been rising. The reasons are still not entirely clear and the consequences have yet to be well evaluated. (MLH)

  15. Acidic precipitation

    SciTech Connect

    Martin, H.C.

    1987-01-01

    At the International Symposium on Acidic Precipitation, over 400 papers were presented, and nearly 200 of them are included here. They provide an overview of the present state of the art of acid rain research. The Conference focused on atmospheric science (monitoring, source-receptor relationships), aquatic effects (marine eutrophication, lake acidification, impacts on plant and fish populations), and terrestrial effects (forest decline, soil acidification, etc.).

  16. Biocatalytic Desulfurization Capabilities of a Mixed Culture during Non-Destructive Utilization of Recalcitrant Organosulfur Compounds

    PubMed Central

    Ismail, Wael; El-Sayed, Wael S.; Abdul Raheem, Abdul Salam; Mohamed, Magdy E.; El Nayal, Ashraf M.

    2016-01-01

    We investigated the biodesulfurization potential of a mixed culture AK6 enriched from petroleum hydrocarbons-polluted soil with dibenzothiophene (DBT) as a sulfur source. In addition to DBT, AK6 utilized the following compounds as sulfur sources: 4-methyldibenzothiophene (4-MDBT), benzothiophene (BT), and 4,6- dimethyldibenzothiophene (4,6-DM-DBT). None of these compounds supported the growth of AK6 as the sole carbon and sulfur source. AK6 could not grow on dibenzylsulfide (DBS) as a sulfur source. The AK6 community structure changed according to the provided sulfur source. The major DGGE bands represented members of the genera Sphingobacterium, Klebsiella, Pseudomonas, Stenotrophomonas, Arthrobacter, Mycobacterium, and Rhodococcus. Sphingobacterium sp. and Pseudomonas sp. were abundant across all cultures utilizing any of the tested thiophenic S-compounds. Mycobacterium/Rhodococcus spp. were restricted to the 4-MDBT culture. The 4-MDBT culture had the highest species richness and diversity. Biodesulfurization of DBT by resting cells of AK6 produced 2-hydroxybiphenyl (2-HBP) in addition to trace amounts of phenylacetate. AK6 transformed DBT to 2-hydroxybiphenyl with a specific activity of 9 ± 0.6 μM 2-HBP g dry cell weight−1 h−1. PCR confirmed the presence in the AK6 community of the sulfur-specific (4S) pathway genes dszB and dszC. Mixed cultures hold a better potential than axenic ones for the development of a biodesulfurization technology. PMID:26973637

  17. Synthesis and Biological Evaluation of (S)-Amino-2-methyl-4-[76Br]bromo-3-(E)-butenoic Acid (BrVAIB) for Brain Tumor Imaging

    PubMed Central

    Burkemper, Jennifer L.; Huang, Chaofeng; Li, Aixiao; Yuan, Liya; Rich, Keith; McConathy, Jonathan; Lapi, Suzanne E.

    2016-01-01

    The novel compound, (S)-amino-2-methyl-4-[76Br]-bromo-3-(E)-butenoic acid (BrVAIB, [76Br]5), was characterized against the known system A tracer, IVAIB ([123I]8). [76Br]5 was prepared in a 51% ± 19% radiochemical yield with high radiochemical purity (≥98%). The biological properties of [76Br]5 were compared with those of [123I]8. Results showed that [76Br]5 undergoes mixed amino acid transport by system A and system L transport, while [123I]8 had less uptake by system L. [76Br]5 demonstrated higher uptake than [123I]8 in DBT tumors 1 h after injection (3.7 ± 0.4% ID/g vs 1.5 ± 0.3% ID/g) and also showed higher uptake vs [123I]8 in normal brain. Small animal PET studies with [76Br]5 demonstrated good tumor visualization of intracranial DBTs up to 24 h with clearance from normal tissues. These results indicate that [76Br]5 is a promising PET tracer for brain tumor imaging and lead compound for a mixed system A and system L transport substrate. PMID:26444035

  18. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.

    1993-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  19. Acid Rain

    USGS Publications Warehouse

    Bricker, Owen P.; Rice, Karen C.; Dietrich, W.E.; Sposito, Garrison

    1997-01-01

    Acid deposition, or acid rain as it is more commonly referred to, has become a widely publicized environmental issue in the U.S. over the past decade. The term usually conjures up images of fish kills, dying forests, "dead" lakes, and damage to monuments and other historic artifacts. The primary cause of acid deposition is emission of S02 and NOx to the atmosphere during the combustion of fossil fuels. Oxidation of these compounds in the atmosphere forms strong acids - H2SO4 and HNO3 - which are returned to the Earth in rain, snow, fog, cloud water, and as dry deposition.Although acid deposition has only recently been recognized as an environmental problem in the U.S., it is not a new phenomenon (Cogbill & Likens 1974). As early as the middle of the 17th century in England, the deleterious effects of industrial emissions on plants, animals, and humans, and the atmospheric transport of pollutants between England and France had become issues of concern (Evelyn 1661, Graunt 1662). It is interesting that well over three hundred years ago in England, recommendations were made to move industry outside of towns and build higher chimneys to spread the pollution into "distant parts." Increasing the height of smokestacks has helped alleviate local problems, but has exacerbated others. In the U.S. the height of the tallest smokestack has more than doubled, and the average height of smokestacks has tripled since the 1950s (Patrick et al 1981). This trend occurred in most industrialized nations during the 20th century and has had the effect of transforming acid rain from a local urban problem into a problem of global scale.

  20. Salicylic acids

    PubMed Central

    Hayat, Shamsul; Irfan, Mohd; Wani, Arif; Nasser, Alyemeni; Ahmad, Aqil

    2012-01-01

    Salicylic acid is well known phytohormone, emerging recently as a new paradigm of an array of manifestations of growth regulators. The area unleashed yet encompassed the applied agriculture sector to find the roles to strengthen the crops against plethora of abiotic and biotic stresses. The skipped part of integrated picture, however, was the evolutionary insight of salicylic acid to either allow or discard the microbial invasion depending upon various internal factors of two interactants under the prevailing external conditions. The metabolic status that allows the host invasion either as pathogenesis or symbiosis with possible intermediary stages in close systems has been tried to underpin here. PMID:22301975

  1. Selenious acid

    Integrated Risk Information System (IRIS)

    Selenious acid ; CASRN 7783 - 00 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  2. Dichloroacetic acid

    Integrated Risk Information System (IRIS)

    EPA 635 / R - 03 / 007 www.epa.gov / iris TOXICOLOGICAL REVIEW OF DICHLOROACETIC ACID ( CAS No . 79 - 43 - 6 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) August 2003 U.S . Environmental Protection Agency Washington , DC DISCLAIMER This document has been revi

  3. Trichloroacetic acid

    Integrated Risk Information System (IRIS)

    EPA / 635 / R - 09 / 003F www.epa.gov / iris TOXICOLOGICAL REVIEW OF TRICHLOROACETIC ACID ( CAS No . 76 - 03 - 9 ) In Support of Summary Information on the Integrated Risk Information System ( IRIS ) September 2011 U.S . Environmental Protection Agency Washington , DC ii DISCLAIMER This document has

  4. Acid rain

    SciTech Connect

    Not Available

    1984-06-01

    An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

  5. Benzoic acid

    Integrated Risk Information System (IRIS)

    Benzoic acid ; CASRN 65 - 85 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  6. Formic acid

    Integrated Risk Information System (IRIS)

    Formic acid ; CASRN 64 - 18 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  7. Acrylic acid

    Integrated Risk Information System (IRIS)

    Acrylic acid ( CASRN 79 - 10 - 7 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  8. Phosphoric acid

    Integrated Risk Information System (IRIS)

    Phosphoric acid ; CASRN 7664 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  9. Cacodylic acid

    Integrated Risk Information System (IRIS)

    Cacodylic acid ; CASRN 75 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  10. Azelaic acid.

    PubMed

    Nazzaro-Porro, M

    1987-12-01

    This review is an update on the literature accumulated over the past 10 years following the original observation that azelaic acid, a naturally occurring and nontoxic C9 dicarboxylic acid, possesses significant biologic properties and a potential as a therapeutic agent. These studies have shown that azelaic acid is a reversible inhibitor of tyrosinase and other oxidoreductases in vitro and that it inhibits mitochondrial respiration. It can also inhibit anaerobic glycolysis. Both in vitro and in vivo it has an antimicrobial effect on both aerobic and anaerobic (Propionibacterium acnes) microorganisms. In tissue culture it exerts a dose- and time-dependent cytotoxic effect on malignant melanocytes, associated with mitochondrial damage and inhibition of deoxyribonucleic acid (DNA) synthesis. Tumoral cell lines not containing tyrosinase are equally affected. Normal cells in culture exposed to the same concentrations of the diacid that are toxic for tumoral cells are in general not damaged. Radioactive azelaic acid has been shown to penetrate tumoral cells at a higher level than normal cells of the corresponding line. Topically applied (a 20% cream), it has been shown to be of therapeutic value in skin disorders of different etiologies. Its beneficial effect on various forms of acne (comedogenic, papulopustular, nodulocystic) has been clearly demonstrated. Particularly important is its action on abnormal melanocytes, which has led to the possibility of obtaining good results on melasma and highly durable therapeutic responses on lentigo maligna. It is also capable of causing regression of cutaneous malignant melanoma, but its role in melanoma therapy remains to be investigated.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Chemical and biological assessment of Angelica herbal decoction: comparison of different preparations during historical applications.

    PubMed

    Zhang, Wendy Li; Zheng, Ken Yu-Zhong; Zhu, Kevin Yue; Zhan, Janis Ya-Xian; Bi, Cathy Wen-Chuan; Chen, Jian-Ping; Du, Crystal Ying-Qing; Zhao, Kui-Jun; Lau, David Tai-Wai; Dong, Tina Ting-Xia; Tsim, Karl Wah-Keung

    2012-08-15

    The commonly used Angelica herbal decoction today is Danggui Buxue Tang (DBT), which is a dietary supplement in treating menopausal irregularity in women, i.e. to nourish "Qi" and to enrich "Blood". According to historical record, many herbal decoctions were also named DBT, but the most popular formulation of DBT was written in Jin dynasty (1247 AD) of China, which contained Astragali Radix (AR) and Angelicae Sinensis Radix (ASR) with a weight ratio of 5:1. However, at least two other Angelica herbal decoctions recorded as DBT were prescribed in Song (1155 AD) and Qing dynasties (1687 AD). Although AR and ASR are still the major components in the DBT herbal decoctions, they are slightly varied in the herb composition. In order to reveal the efficiency of different Angelica herbal decoctions, the chemical and biological properties of three DBT herbal extracts were compared. Significantly, the highest amounts of AR-derived astragaloside III, astragaloside IV, calycosin and formononetin and ASR-derived ferulic acid were found in DBT described in 1247 AD: this preparation showed stronger activities in osteogenic, estrogenic and erythropoetic effects than the other two DBT. The current results supported the difference of three DBT in chemical and biological properties, which could be a result of different herbal combinations. For the first time, this study supports the popularity of DBT described in 1247 AD.

  12. Hydroxycarboxylic acids and salts

    DOEpatents

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  13. Acidic domains around nucleic acids.

    PubMed Central

    Lamm, G; Pack, G R

    1990-01-01

    The hydrogen ion concentration in the vicinity of DNA was mapped out within the Poisson-Boltzmann approximation. Experimental conditions were modeled by assuming Na-DNA to be solvated in a buffer solution containing 45 mM Tris and 3 mM Mg cations at pH 7.5. Three regions of high H+ concentration (greater than 10 microM) are predicted: one throughout the minor groove of DNA and two localized in the major groove near N7 of guanine and C5 of cytosine for a G.C base pair. These acidic domains correlate well with the observed covalent binding sites of benzo[a]pyrene epoxide (N2 of guanine) and of aflatoxin B1 epoxide (N7 of guanine), chemical carcinogens that presumably undergo acid catalysis to form highly reactive carbocations that ultimately bind to DNA. It is suggested that these regions of high H+ concentration may also be of concern in understanding interactions involving proteins and noncarcinogenic molecules with or near nucleic acids. PMID:2123348

  14. Folic Acid and Pregnancy

    MedlinePlus

    ... Feeding Your 1- to 2-Year-Old Folic Acid and Pregnancy KidsHealth > For Parents > Folic Acid and ... before conception and during early pregnancy . About Folic Acid Folic acid, sometimes called folate, is a B ...

  15. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  16. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to new compounds, 7,10-dihydroxy-8(E)-octadecen...

  17. New bioactive fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  18. Proteomics and Metabolomics Analyses to Elucidate the Desulfurization Pathway of Chelatococcus sp.

    PubMed Central

    Chaudhuri, Mihir K.

    2016-01-01

    Desulfurization of dibenzothiophene (DBT) and alkylated DBT derivatives present in transport fuel through specific cleavage of carbon-sulfur (C-S) bonds by a newly isolated bacterium Chelatococcus sp. is reported for the first time. Gas chromatography-mass spectrometry (GC-MS) analysis of the products of DBT degradation by Chelatococcus sp. showed the transient formation of 2-hydroxybiphenyl (2-HBP) which was subsequently converted to 2-methoxybiphenyl (2-MBP) by methylation at the hydroxyl group of 2-HBP. The relative ratio of 2-HBP and 2-MBP formed after 96 h of bacterial growth was determined at 4:1 suggesting partial conversion of 2-HBP or rapid degradation of 2-MBP. Nevertheless, the enzyme involved in this conversion process remains to be identified. This production of 2-MBP rather than 2-HBP from DBT desulfurization has a significant metabolic advantage for enhancing the growth and sulfur utilization from DBT by Chelatococcus sp. and it also reduces the environmental pollution by 2-HBP. Furthermore, desulfurization of DBT derivatives such as 4-M-DBT and 4, 6-DM-DBT by Chelatococcus sp. resulted in formation of 2-hydroxy-3-methyl-biphenyl and 2-hydroxy –3, 3/- dimethyl-biphenyl, respectively as end product. The GC and X-ray fluorescence studies revealed that Chelatococcus sp. after 24 h of treatment at 37°C reduced the total sulfur content of diesel fuel by 12% by per gram resting cells, without compromising the quality of fuel. The LC-MS/MS analysis of tryptic digested intracellular proteins of Chelatococcus sp. when grown in DBT demonstrated the biosynthesis of 4S pathway desulfurizing enzymes viz. monoxygenases (DszC, DszA), desulfinase (DszB), and an NADH-dependent flavin reductase (DszD). Besides, several other intracellular proteins of Chelatococcus sp. having diverse biological functions were also identified by LC-MS/MS analysis. Many of these enzymes are directly involved with desulfurization process whereas the other enzymes/proteins support

  19. Acid rain

    SciTech Connect

    Boyle, R.H.; Boyle, R.A.

    1983-01-01

    Acid rain, says Boyle is a chemical leprosy eating into the face of North America and Europe, perhaps the major ecological problem of our time. Boyle describes the causes and scope of the phenomenon; the effects on man, wildlife, water, and our cultural heritage. He probes the delays of politicians and the frequent self-serving arguments advanced by industry in the face of what scientists have proved. The solutions he offers are to strengthen the Clean Air Act and require emission reductions that can be accomplished by establishing emission standards on a regional or bubble basis, burn low-sulfur coal, install scrubbers at critical plants, and invest in alternative energy sources. 73 references, 1 figure.

  20. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae

    SciTech Connect

    Krawiec, S.

    1991-11-09

    This department of energy-sponsored mission-oriented research project currently has three emphases. They are: (1) determining the kinetics of monohydroxybiphenyl (OH-BP) production in batch culture by N1-36, an unidentified soil isolate, when the organism is presented with dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}); (2) establishing reliable methods for physically characterizing R68.45, a broad host range plasmid; and (3) attempting to elicit a physiologically consistent and genetically stable ability of some gram negative soil isolates to convert DBT to o,o{prime}-biphenol. Eachh of these goals has subsidiary components. For example, in addition to establishing kinetics of formation of OH-BP by N1-36, analyses have been or will be performed to determine whether the catalytic activity can be achieved with irradiated cells, spheroplasts, and cell extracts. This report presents information on progress towards fulfilling both the principal goals listed above and some relevant ancillary activities.

  1. [Teichoic acids from lactic acid bacteria].

    PubMed

    Livins'ka, O P; Harmasheva, I L; Kovalenko, N K

    2012-01-01

    The current view of the structural diversity of teichoic acids and their involvement in the biological activity of lactobacilli has been reviewed. The mechanisms of effects of probiotic lactic acid bacteria, in particular adhesive and immunostimulating functions have been described. The prospects of the use of structure data of teichoic acid in the assessment of intraspecific diversity of lactic acid bacteria have been also reflected.

  2. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Tenth quarterly report

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate (``4S``) pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a ``fermentor`` for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  3. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  4. Organic acids tunably catalyze carbonic acid decomposition.

    PubMed

    Kumar, Manoj; Busch, Daryle H; Subramaniam, Bala; Thompson, Ward H

    2014-07-10

    Density functional theory calculations predict that the gas-phase decomposition of carbonic acid, a high-energy, 1,3-hydrogen atom transfer reaction, can be catalyzed by a monocarboxylic acid or a dicarboxylic acid, including carbonic acid itself. Carboxylic acids are found to be more effective catalysts than water. Among the carboxylic acids, the monocarboxylic acids outperform the dicarboxylic ones wherein the presence of an intramolecular hydrogen bond hampers the hydrogen transfer. Further, the calculations reveal a direct correlation between the catalytic activity of a monocarboxylic acid and its pKa, in contrast to prior assumptions about carboxylic-acid-catalyzed hydrogen-transfer reactions. The catalytic efficacy of a dicarboxylic acid, on the other hand, is significantly affected by the strength of an intramolecular hydrogen bond. Transition-state theory estimates indicate that effective rate constants for the acid-catalyzed decomposition are four orders-of-magnitude larger than those for the water-catalyzed reaction. These results offer new insights into the determinants of general acid catalysis with potentially broad implications.

  5. Plasma amino acids

    MedlinePlus

    Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

  6. Uric acid - urine

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003616.htm Uric acid urine test To use the sharing features on this page, please enable JavaScript. The uric acid urine test measures the level of uric acid ...

  7. Facts about Folic Acid

    MedlinePlus

    ... Information For... Media Policy Makers Facts About Folic Acid Language: English Español (Spanish) Recommend on Facebook Tweet ... of the baby's brain and spine. About folic acid Folic acid is a B vitamin. Our bodies ...

  8. Stomach acid test

    MedlinePlus

    Gastric acid secretion test ... of the cells in the stomach to release acid. The stomach contents are then removed and analyzed. ... 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour in ...

  9. Methylmalonic acid blood test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003565.htm Methylmalonic acid blood test To use the sharing features on this page, please enable JavaScript. The methylmalonic acid blood test measures the amount of methylmalonic acid ...

  10. Uric acid test (image)

    MedlinePlus

    Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

  11. Fatty Acid Oxidation Disorders

    MedlinePlus

    ... other health conditions > Fatty acid oxidation disorders Fatty acid oxidation disorders E-mail to a friend Please ... these disorders, go to genetests.org . What fatty acid oxidation disorders are tested for in newborn screening? ...

  12. Acid distribution in phosphoric acid fuel cells

    SciTech Connect

    Okae, I.; Seya, A.; Umemoto, M.

    1996-12-31

    Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

  13. Compatibility Study of Danggui Buxue Tang on Chemical Ingredients, Angiogenesis and Endothelial Function

    PubMed Central

    Lin, Ping-Lan; Li, Zhi-Cheng; Xie, Rui-Fang; Wang, You-Hua; Zhou, Xin

    2017-01-01

    Danggui Buxue Tang (DBT) is a classic Chinese herbal formula which consists of Astragali mongholici Radix and Angelica sinensis Radix (ASR). For chemical ingredients, HPLC were performed. Results showed compared with single herbs, DBT decoction could promote the dissolution of ingredients such as ferulic acid and calycosin. Furthermore, when ratio of AMR to ASR was 5 to 1, synthetic score was the best. For angiogenesis, normal and injured zebrafish model were applied. Results showed DBT and its ingredients had angiogenesis effects on Sub Intestinal vessels (SIVs) of normal zebrafish. Meanwhile, DBT and its single herbs could also recover Inter-Segmental Vessels (ISVs) injured by VRI. Angiogenesis effects of DBT on ISVs were better than single herbs. AMR extract, Total Saponins of AMR, Polysaccharide of ASR, ferulic acid, calycosin and calycosin-7-glucoside could be effective ingredients for angiogenisis. For endothelium functions, Lysoph-Osphatidyl choline was used to damage rat endothelial function of thoracic aorta. The results showed DBT and its single herbs could improve endothelial dysfunctions in dose-dependence. Both ferulic acid and calycosin-7-glucoside could also improve endothelium dysfunction in dose dependence. Therefore, compatibility of DBT was reasonable. Compared with single herbs, DBT could promote dissolution of effective ingredients, enhance angiogenesis and relieve endothelial dysfunction. PMID:28327640

  14. Demonstration-Based Training (DBT) in the Design of a Video Tutorial for Software Training

    ERIC Educational Resources Information Center

    van der Meij, Hans; van der Meij, Jan

    2016-01-01

    This study investigates the design and effectiveness of a video tutorial for software training. In accordance with demonstration-based training, the tutorial consisted of a series of task demonstrations, with instructional features added to enhance learning. An experiment is reported in which a demonstration-only control condition was compared…

  15. IMMUNE FUNCTION IN ADULT RATS EXPOSED TO DBT IN DRINKING WATER

    EPA Science Inventory

    Organotins are used commercially as agricultural pesticides, antifouling agents and stabilizers for polyvinyl chloride (PVC) pipe. Mono- and di-substituted methyl and butyltins, used in PVC pipe production, are of concern to the USEPA as they leach from supply pipes into drinking...

  16. Acid tolerance in amphibians

    SciTech Connect

    Pierce, B.A.

    1985-04-01

    Studies of amphibian acid tolerance provide information about the potential effects of acid deposition on amphibian communities. Amphibians as a group appear to be relatively acid tolerant, with many species suffering increased mortality only below pH 4. However, amphibians exhibit much intraspecific variation in acid tolerance, and some species are sensitive to even low levels of acidity. Furthermore, nonlethal effects, including depression of growth rates and increases in developmental abnormalities, can occur at higher pH.

  17. Gas-phase acidities of aspartic acid, glutamic acid, and their amino acid amides

    NASA Astrophysics Data System (ADS)

    Li, Zhong; Matus, Myrna H.; Velazquez, Hector Adam; Dixon, David A.; Cassady, Carolyn J.

    2007-09-01

    Gas-phase acidities (GA or [Delta]Gacid) for the two most acidic common amino acids, aspartic acid and glutamic acid, have been determined for the first time. Because of the amide linkage's importance in peptides and as an aid in studying side chain versus main chain deprotonation, aspartic acid amide and glutamic acid amide were also studied. Experimental GA values were measured by proton transfer reactions in an electrospray ionization/Fourier transform ion cyclotron resonance mass spectrometer. Calculated GAs were obtained by density functional and molecular orbital theory approaches. The best agreement with experiment was found at the G3MP2 level; the MP2/CBS and B3LYP/aug-cc-pVDZ results are 3-4 kcal/mol more acidic than the G3MP2 results. Experiment shows that aspartic acid is more acidic than glutamic acid by ca. 3 kcal/mol whereas the G3MP2 results show a smaller acidity difference of 0.2 kcal/mol. Similarly, aspartic acid amide is experimentally observed to be ca. 2 kcal/mol more acidic than glutamic acid amide whereas the G3MP2 results show a correspondingly smaller energy difference of 0.7 kcal/mol. The computational results clearly show that the anions are all ring-like structures with strong hydrogen bonds between the OH or NH2 groups and the CO2- group from which the proton is removed. The two amino acids are main-chain deprotonated. In addition, use of the COSMO model for the prediction of the free energy differences in aqueous solution gave values in excellent agreement with the most recent experimental values for pKa. Glutamic acid is predicted to be more acidic than aspartic acid in aqueous solution due to differential solvation effects.

  18. Toxicity of adipic acid.

    PubMed

    Kennedy, Gerald L

    2002-05-01

    Adipic acid has very low acute toxicity in rats with an LD50 > 5000 mg/kg. Adipic acid produced mild to no skin irritation on intact guinea pig skin as a 50% concentration in propylene glycol; it was not a skin sensitizer. Adipic acid caused mild conjunctival irritation in washed rabbit eyes; in unwashed rabbit eyes, there was mild conjunctival irritation, minimal iritis, but no corneal effects. Adipic acid dust may irritate the mucous membranes of the lungs and nose. In a 2-year feeding study, rats fed adipic acid at concentrations up to 5% in the diet exhibited only weight loss. Adipic acid is not genetically active in a wide variety of assay systems. Adipic acid caused no developmental toxicity in mice, rats, rabbits, or hamsters when administered orally. Adipic acid is partially metabolized in humans; the balance is eliminated unchanged in the urine. Adipic acid is slightly to moderately toxic to fish, daphnia, and algae in acute tests.

  19. Preparation of WO3/g-C3N4 composites and their application in oxidative desulfurization

    NASA Astrophysics Data System (ADS)

    Zhao, Rongxiang; Li, Xiuping; Su, Jianxun; Gao, Xiaohan

    2017-01-01

    WO3/graphitic carbon nitride (g-C3N4) composites were successfully synthesized through direct calcining of a mixture of WO3 and g-C3N4 at 400 °C for 2 h. The WO3 was prepared by calcination of phosphotungstic acid at 550 °C for 4 h, and the g-C3N4 was obtained by calcination of melamine at 520 °C for 4 h. The WO3/g-C3N4 composites were characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and Brunner-Emmett-Teller analysis (BET). The WO3/g-C3N4 composites exhibited stronger XRD peaks of WO3 and g-C3N4 than the WO3 and pure g-C3N4. In addition, two WO3 peaks at 25.7° and 26.6° emerged for the 36% -WO3/g-C3N4 composite. This finding indicated that WO3 was highly dispersed on the surface of the g-C3N4 nanosheets and interacted with the nanosheets, which resulted in the appearance of (012) and (022) planes of WO3. The WO3/g-C3N4 composite also exhibited a larger specific surface area and higher degree of crystallization than WO3 or pure g-C3N4, which resulted in high catalytic activity of the catalyst. Desulfurization experiments demonstrated that the desulfurization rate of dibenzothiophene (DBT) in model oil reached 91.2% under optimal conditions. Moreover, the activity of the catalyst was not significantly decreased after five recycles.

  20. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    This communication notes the actual magnitude of the acidity in acidic fog particles and suggests a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air.

  1. Acid Thunder: Acid Rain and Ancient Mesoamerica

    ERIC Educational Resources Information Center

    Kahl, Jonathan D. W.; Berg, Craig A.

    2006-01-01

    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  2. Molecular biological enhancement of coal desulfurization. Final report

    SciTech Connect

    Krawiec, S.

    1994-12-31

    During the period from 1986 through 1993 the prospect of bacterial desulfurization of fossil fuel was transformed from a theoretically appealing concept to a demonstrable laboratory phenomenon. Results from several laboratories confirmed that there was not one but, rather, several metabolic bases of selectively removing sulfur from the carbon frame of sulfur-containing organic compounds characteristic of fossil fuels. Results in this report relate solely to the so-called ``4S`` pathway (named for the four sulfur-containing compounds in the sequence: (l) dibenzothiophene [DBT] {yields} (2) dibenzothiophene sulfoxide [DBTO] {yields} (3) dibenzosulfone [DBTO{sup 2}] {yields} (4) dibenzosulfonate {yields} monohydroxybiphenyl [OH-BP] + SO{sub 4}{sup =}. [An additional desulfurized product, biphenyl, has been hypothesized and another, o,o{prime}-biphenyl, observed.]) The following subjects are discussed: isolating bacteria with a DbtS{sup +} phenotype; confirming the production of a desulfurized product; determining the identity of the isolates; determining the growth characteristics of the isolates in batch and continuous cultures; determining the kinetics and yields of product in batch and continuous cultures.

  3. Fatty acid analogs

    DOEpatents

    Elmaleh, David R.; Livni, Eli

    1985-01-01

    In one aspect, a radioactively labeled analog of a fatty acid which is capable of being taken up by mammalian tissue and which exhibits an in vivo beta-oxidation rate below that with a corresponding radioactively labeled fatty acid.

  4. Omega-3 fatty acids

    PubMed Central

    Schwalfenberg, Gerry

    2006-01-01

    OBJECTIVE To examine evidence for the role of omega-3 fatty acids in cardiovascular disease. QUALITY OF EVIDENCE PubMed was searched for articles on the role of omega-3 fatty acids in cardiovascular disease. Level I and II evidence indicates that omega-3 fatty acids are beneficial in improving cardiovascular outcomes. MAIN MESSAGE Dietary intake of omega-3 fatty acids has declined by 80% during the last 100 years, while intake of omega-6 fatty acids has greatly increased. Omega-3 fatty acids are cardioprotective mainly due to beneficial effects on arrhythmias, atherosclerosis, inflammation, and thrombosis. There is also evidence that they improve endothelial function, lower blood pressure, and significantly lower triglycerides. CONCLUSION There is good evidence in the literature that increasing intake of omega-3 fatty acids improves cardiac outcomes. Physicians need to integrate dietary recommendations for consumption of omega-3 fatty acids into their usual cardiovascular care. PMID:16812965

  5. Sulfuric acid poisoning

    MedlinePlus

    Sulfuric acid is a very strong chemical that is corrosive. Corrosive means it can cause severe burns and ... or mucous membranes. This article discusses poisoning from sulfuric acid. This article is for information only. Do NOT ...

  6. Lactic acid test

    MedlinePlus

    Lactate test ... test. Exercise can cause a temporary increase in lactic acid levels. ... not getting enough oxygen. Conditions that can increase lactic acid levels include: Heart failure Liver disease Lung disease ...

  7. Folic Acid Quiz

    MedlinePlus

    ... About Us Information For... Media Policy Makers Folic Acid Quiz Language: English Español (Spanish) Recommend on Facebook ... button beside the question. Good Luck! 1. Folic acid is: A a B vitamin B a form ...

  8. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  9. Azelaic Acid Topical

    MedlinePlus

    Azelaic acid gel and foam is used to clear the bumps, lesions, and swelling caused by rosacea (a skin ... redness, flushing, and pimples on the face). Azelaic acid cream is used to treat the pimples and ...

  10. Zoledronic Acid Injection

    MedlinePlus

    Zoledronic acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and weak ... of life,' end of regular menstrual periods). Zoledronic acid (Reclast) is also used to treat osteoporosis in ...

  11. Alpha Hydroxy Acids

    MedlinePlus

    ... Cosmetics Home Cosmetics Products & Ingredients Ingredients Alpha Hydroxy Acids Share Tweet Linkedin Pin it More sharing options ... for Industry: Labeling for Cosmetics Containing Alpha Hydroxy Acids The following information is intended to answer questions ...

  12. Uric Acid Test

    MedlinePlus

    ... products and services. Advertising & Sponsorship: Policy | Opportunities Uric Acid Share this page: Was this page helpful? Also known as: Serum Urate; UA Formal name: Uric Acid Related tests: Synovial Fluid Analysis , Kidney Stone Analysis , ...

  13. Amino Acid Metabolism Disorders

    MedlinePlus

    ... breaks the food parts down into sugars and acids, your body's fuel. Your body can use this ... process. One group of these disorders is amino acid metabolism disorders. They include phenylketonuria (PKU) and maple ...

  14. Valproic Acid and Pregnancy

    MedlinePlus

    ... live chat Live Help Fact Sheets Share Valproic Acid and Pregnancy Wednesday, 01 July 2015 In every ... This sheet talks about whether exposure to valproic acid may increase the risk for birth defects over ...

  15. Aminocaproic Acid Injection

    MedlinePlus

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  16. Omega-6 Fatty Acids

    MedlinePlus

    Omega-6 fatty acids are types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean oils. Other types of omega-6 fatty acids are found in black currant seed, borage seed, ...

  17. Deoxycholic Acid Injection

    MedlinePlus

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  18. PRODUCTION OF TRIFLUOROACETIC ACID

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-07-19

    A method is given for the production of improved yields of trifluoroacetic acid. The compound is prepared by oxidizing m-aminobenzotrifluoride with an alkali metal or alkaline earth metal permanganate at a temperature in the range of 80 deg C to 100 deg C while dissolved ln a mixture of water with glacial acetic acid and/or trifluoroacetic acid. Preferably a mixture of water and trifluoroacetic acid ls used as the solvent.

  19. Refining Lurgi tar acids

    SciTech Connect

    Greco, N.P.

    1984-04-17

    There is disclosed a process for removing tar bases and neutral oils from the Lurgi tar acids by treating the tar acids with aqueous sodium bisulfate to change the tar bases to salts and to hydrolyze the neutral oils to hydrolysis products and distilling the tar acids to obtain refined tar acid as the distillate while the tar base salts and neutral oil hydrolysis products remain as residue.

  20. Plant fatty acid hydroxylases

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank

    2001-01-01

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  1. 78 FR 20029 - Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic Acid; Tolerance...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... AGENCY 40 CFR Part 180 Castor Oil, Polymer With Adipic Acid, Linoleic Acid, Oleic Acid and Ricinoleic..., polymer with adipic acid, linoleic acid, oleic acid and ricinoleic acid (CAS Reg. No. 1357486-09- 9) when used as an inert ingredient in a pesticide formulation. Advance Polymer Technology submitted a...

  2. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    The chemical composition of fog particles has become of considerable interest, because of both the possibility of interpreting atmospheric- chemistry processes in fog particles in terms of the principles of aqueous chemistry and the potential health effects of species present in fog particles. The acidity of fog particles has received wide attention. This communication noted the actual magnitude of the excess acidity in acidic fog particles and suggested a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air. (DP)

  3. What Is Acid Rain?

    ERIC Educational Resources Information Center

    Likens, Gene E.

    2004-01-01

    Acid rain is the collective term for any type of acidified precipitation: rain, snow, sleet, and hail, as well as the presence of acidifying gases, particles, cloud water, and fog in the atmosphere. The increased acidity, primarily from sulfuric and nitric acids, is generated as a by-product of the combustion of fossil fuels such as coal and oil.…

  4. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  5. Acid Rain Study Guide.

    ERIC Educational Resources Information Center

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  6. Acid Lipase Disease

    MedlinePlus

    ... Page You are here Home » Disorders » All Disorders Acid Lipase Disease Information Page Acid Lipase Disease Information Page What research is being ... research to understand lipid storage diseases such as acid lipase deficiency. Additional research studies hope to identify ...

  7. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  8. ADVANCED OXIDATION PROCESS

    SciTech Connect

    Dr. Colin P. Horwitz; Dr. Terrence J. Collins

    2003-11-04

    The removal of recalcitrant sulfur species, dibenzothiophene and its derivatives, from automotive fuels is an integral component in the development of cleaner burning and more efficient automobile engines. Oxidative desulfurization (ODS) wherein the dibenzothiophene derivative is converted to its corresponding sulfoxide and sulfone is an attractive approach to sulfur removal because the oxidized species are easily extracted or precipitated and filtered from the hydrocarbon phase. Fe-TAML{reg_sign} activators of hydrogen peroxide (TAML is Tetra-Amido-Macrocyclic-Ligand) catalytically convert dibenzothiophene and its derivatives rapidly and effectively at moderate temperatures (50-60 C) and ambient pressure to the corresponding sulfoxides and sulfones. The oxidation process can be performed in both aqueous systems containing alcohols such as methanol, ethanol, or t-butanol, and in a two-phase hydrocarbon/aqueous system containing tert-butanol or acetonitrile. In the biphasic system, essentially complete conversion of the DBT to its oxidized products can be achieved using slightly longer reaction times than in homogeneous solution. Among the key features of the technology are the mild reaction conditions, the very high selectivity where no over oxidation of the sulfur compounds occurs, the near stoichiometric use of hydrogen peroxide, the apparent lack of degradation of sensitive fuel components, and the ease of separation of oxidized products.

  9. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow; Mary Ann D.; Dahlberg, James E.

    2010-11-09

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  10. Amino acid analysis

    NASA Technical Reports Server (NTRS)

    Winitz, M.; Graff, J. (Inventor)

    1974-01-01

    The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

  11. Editorial: Acid precipitation

    SciTech Connect

    1995-09-01

    This editorial focuses on acid rain and the history of public and governmental response to acid rain. Comments on a book by Gwineth Howell `Acid Rain and Acid Waters` are included. The editor feels that Howells has provide a service to the environmental scientific community, with a textbook useful to a range of people, as well as a call for decision makers to learn from the acid rain issue and use it as a model for more sweeping global environmental issues. A balance is needed among several parameters such as level of evidence, probability that the evidence will lead to a specific direction and the cost to the global community. 1 tab.

  12. Nucleic acid detection compositions

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James L.

    2008-08-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  13. Nucleic acid detection assays

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James E.

    2005-04-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  14. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor L.; Brow, Mary Ann D.; Dahlberg, James E.

    2007-12-11

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  15. Nucleic acid detection kits

    DOEpatents

    Hall, Jeff G.; Lyamichev, Victor I.; Mast, Andrea L.; Brow, Mary Ann; Kwiatkowski, Robert W.; Vavra, Stephanie H.

    2005-03-29

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof. The present invention further relates to methods and devices for the separation of nucleic acid molecules based on charge. The present invention also provides methods for the detection of non-target cleavage products via the formation of a complete and activated protein binding region. The invention further provides sensitive and specific methods for the detection of nucleic acid from various viruses in a sample.

  16. [Biosynthesis of adipic acid].

    PubMed

    Han, Li; Chen, Wujiu; Yuan, Fei; Zhang, Yuanyuan; Wang, Qinhong; Ma, Yanhe

    2013-10-01

    Adipic acid is a six-carbon dicarboxylic acid, mainly for the production of polymers such as nylon, chemical fiber and engineering plastics. Its annual demand is close to 3 million tons worldwide. Currently, the industrial production of adipic acid is based on the oxidation of aromatics from non-renewable petroleum resources by chemo-catalytic processes. It is heavily polluted and unsustainable, and the possible alternative method for adipic acid production should be developed. In the past years, with the development of synthetic biology and metabolic engineering, green and clean biotechnological methods for adipic acid production attracted more attention. In this study, the research advances of adipic acid and its precursor production are reviewed, followed by addressing the perspective of the possible new pathways for adipic acid production.

  17. Acidic Ionic Liquids.

    PubMed

    Amarasekara, Ananda S

    2016-05-25

    Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition.

  18. Boric acid and boronic acids inhibition of pigeonpea urease.

    PubMed

    Reddy, K Ravi Charan; Kayastha, Arvind M

    2006-08-01

    Urease from the seeds of pigeonpea was competitively inhibited by boric acid, butylboronic acid, phenylboronic acid, and 4-bromophenylboronic acid; 4-bromophenylboronic acid being the strongest inhibitor, followed by boric acid > butylboronic acid > phenylboronic acid, respectively. Urease inhibition by boric acid is maximal at acidic pH (5.0) and minimal at alkaline pH (10.0), i.e., the trigonal planar B(OH)3 form is a more effective inhibitor than the tetrahedral B(OH)4 -anionic form. Similarly, the anionic form of phenylboronic acid was least inhibiting in nature.

  19. Biotransformation of cinnamic acid, p-coumaric acid, caffeic acid, and ferulic acid by plant cell cultures of Eucalyptus perriniana.

    PubMed

    Katsuragi, Hisashi; Shimoda, Kei; Kubota, Naoji; Nakajima, Nobuyoshi; Hamada, Hatsuyuki; Hamada, Hiroki

    2010-01-01

    Biotransformations of phenylpropanoids such as cinnamic acid, p-coumaric acid, caffeic acid, and ferulic acid were investigated with plant-cultured cells of Eucalyptus perriniana. The plant-cultured cells of E. perriniana converted cinnamic acid into cinnamic acid β-D-glucopyranosyl ester, p-coumaric acid, and 4-O-β-D-glucopyranosylcoumaric acid. p-Coumaric acid was converted into 4-O-β-D-glucopyranosylcoumaric acid, p-coumaric acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcoumaric acid β-D-glucopyranosyl ester, a new compound, caffeic acid, and 3-O-β-D-glucopyranosylcaffeic acid. On the other hand, incubation of caffeic acid with cultured E. perriniana cells gave 3-O-β-D-glucopyranosylcaffeic acid, 3-O-(6-O-β-D-glucopyranosyl)-β-D-glucopyranosylcaffeic acid, a new compound, 3-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, 4-O-β-D-glucopyranosylcaffeic acid, 4-O-β-D-glucopyranosylcaffeic acid β-D-glucopyranosyl ester, ferulic acid, and 4-O-β-D-glucopyranosylferulic acid. 4-O-β-D-Glucopyranosylferulic acid, ferulic acid β-D-glucopyranosyl ester, and 4-O-β-D-glucopyranosylferulic acid β-D-glucopyranosyl ester were isolated from E. perriniana cells treated with ferulic acid.

  20. Photocatalytic degradation of oil industry hydrocarbons models at laboratory and at pilot-plant scale

    SciTech Connect

    Vargas, Ronald; Nunez, Oswaldo

    2010-02-15

    Photodegradation/mineralization (TiO{sub 2}/UV Light) of the hydrocarbons: p-nitrophenol (PNP), naphthalene (NP) and dibenzothiophene (DBT) at three different reactors: batch bench reactor (BBR), tubular bench reactor (TBR) and tubular pilot-plant (TPP) were kinetically monitored at pH = 3, 6 and 10, and the results compared using normalized UV light exposition times. The results fit the Langmuir-Hinshelwood (LH) model; therefore, LH adsorption equilibrium constants (K) and apparent rate constants (k) are reported as well as the apparent pseudo-first-order rate constants, k{sub obs}{sup '} = kK/(1 + Kc{sub r}). The batch bench reactor is the most selective reactor toward compound and pH changes in which the reactivity order is: NP > DBT > PNP, however, the catalyst adsorption (K) order is: DBT > NP > PNP at the three pH used but NP has the highest k values. The tubular pilot-plant (TPP) is the most efficient of the three reactors tested. Compound and pH photodegradation/mineralization selectivity is partially lost at the pilot plant where DBT and NP reaches ca. 90% mineralization at the pH used, meanwhile, PNP reaches only 40%. The real time, in which these mineralization occur are: 180 min for PNP and 60 min for NP and DBT. The mineralization results at the TPP indicate that for the three compounds, the rate limiting step is the same as the degradation one. So that, there is not any stable intermediate that may accumulate during the photocatalytic treatment. (author)

  1. Process for the preparation of lactic acid and glyceric acid

    DOEpatents

    Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

    2008-12-02

    Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

  2. Microorganisms for producing organic acids

    DOEpatents

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  3. DEEP DESULFURIZATION OF DIESEL FUELS BY A NOVEL INTEGRATED APPROACH

    SciTech Connect

    Xiaoliang Ma; Michael Sprague; Lu Sun; Chunshan Song

    2002-10-01

    In order to reduce the sulfur level in liquid hydrocarbon fuels for environmental protection and fuel cell applications, deep desulfurization of a model diesel fuel and a real diesel fuel was conducted by our SARS (selective adsorption for removing sulfur) process using the adsorbent A-2. Effect of temperature on the desulfurization process was examined. Adsorption desulfurization at ambient temperature, 24 h{sup -1} of LHSV over A-2 is efficient to remove dibenzothiophene (DBT) in the model diesel fuel, but difficult to remove 4-methyldibenzothiophene (4-MDBT) and 4,6-dimethyl-dibenzothiophene (4,6-DMDBT). Adsorption desulfurization at 150 C over A-2 can efficiently remove DBT, 4-MDBT and 4,6-DMDBT in the model diesel fuel. The sulfur content in the model diesel fuel can be reduced to less than 1 ppmw at 150 C without using hydrogen gas. The adsorption capacity corresponding to the break-through point is 6.9 milligram of sulfur per gram of A-2 (mg-S/g-A-2), and the saturate capacity is 13.7 mg-S/g-A-2. Adsorption desulfurization of a commercial diesel fuel with a total sulfur level of 47 ppmw was also performed at ambient temperature and 24 h{sup -1} of LHSV over the adsorbent A-2. The results show that only part of the sulfur compounds existing in the low sulfur diesel can be removed by adsorption over A-2 at such operating conditions, because (1) the all sulfur compounds in the low sulfur diesel are the refractory sulfur compounds that have one or two alkyl groups at the 4- and/or 6-positions of DBT, which inhibit the approach of the sulfur atom to the adsorption site; (2) some compounds coexisting in the commercial low sulfur diesel probably inhibit the interaction between the sulfur compounds and the adsorbent. Further work in determining the optimum operating conditions and screening better adsorbent is desired.

  4. Facilitated and selective oxidation of thiophenic sulfur compounds using MoOx/Al₂O₃-H₂O₂ system under ultrasonic irradiation.

    PubMed

    Akbari, Azam; Omidkhah, Mohammadreza; Towfighi Darian, Jafar

    2015-03-01

    Oxidative desulfurization of thiophenic sulfur compounds of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT) with MoOx/Al₂O₃ catalyst and H₂O₂ oxidant has been facilitated and more selective under ultrasonic irradiation. The catalyst with the optimum 10% of Mo loading consisted of isolated tetrahedral molybdenum oxide species based on FTIR analysis. The increase of Mo loading to 15% and 20% caused to generation of polymolybdate and MoO₃ crystals which decreased desulfurization activity. Sonication enhanced the apparent reaction rate constants in oxidation of all three sulfur compounds. An increase in the Arrhenius factor (A0), which is the total number of collisions per second, could explain the acceleration in the rate constants by sonication. The apparent activated energy (Ea) of BT oxidation was reduced from 96.6 to 75.3 kJ/mol by using ultrasound. This indicated that ultrasound had also a chemical effect, like a catalytic influence, in the acceleration of BT removal. DBT oxidation was reduced when investigated in the presence of tetralin, naphthalene and 2-methyl naphthalene as the model aromatic compounds of actual light oils. A higher selectivity toward DBT elimination in the presence of aromatics was obtained by sonication when compared with the silent treatment. Ultrasound cleaned the catalyst surface from adsorbed aromatics. On the basis of the obtained results, a mechanistic proposal for this desulfurization was explained. Oxidation was performed by nucleophilic attack of sulfur atom to the molybdenum peroxide species of tetrahedral molybdates, which was more advanced by sonication.

  5. Citric Acid Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie L. (Compiler)

    2013-01-01

    The Ground Systems Development and Operations GSDO) Program at NASA John F. Kennedy Space Center (KSC) has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of the GSDO Program, the purpose of this project is to demonstratevalidate citric acid as a passivation agent for stainless steel. Successful completion of this project will result in citric acid being qualified for use as an environmentally preferable alternative to nitric acid for passivation of stainless steel alloys in NASA and DoD applications.

  6. Short-term and long-term effect of diaphragm biofeedback training in gastroesophageal reflux disease: an open-label, pilot, randomized trial.

    PubMed

    Sun, X; Shang, W; Wang, Z; Liu, X; Fang, X; Ke, M

    2016-10-01

    This study investigated the effectiveness of diaphragm biofeedback training (DBT) for patients with gastroesophageal reflux disease (GERD). A total of 40 patients with GERD treated at the Peking Union Medical College Hospital between September 2004 and July 2006 were randomized to receive DBT and rabeprazole proton pump inhibitor (PPI) or rabeprazole alone. The DBT + rabeprazole group received DBT during the 8-week initial treatment; the rabeprazole group did not. During the 6-month follow up, all patients took acid suppression according to their reflux symptoms, and the patients in the DBT + rabeprazole group were required to continue DBT. The primary outcome (used for power analysis) was the amount of acid suppression used at 6 months. Secondary outcomes were reflux symptoms, health-related quality of life (HRQL), and esophageal motility differences after the 8-week treatment compared with baseline. Acid suppression usage significantly decreased in the DBT + rabeprazole group compared with the rabeprazole group at 6 months (P < 0.05). At 8 weeks, reflux symptoms and GERD-HRQL were significantly improved in both groups (P < 0.05), without difference between them. Crural diaphragm tension (CDT) and gastroesophageal junction pressure (GEJP) significantly increased in the DBT + rabeprazole group (P < 0.05), but without change in lower esophageal sphincter (LES) pressure. There was no significant change in CDT, GEJP, and LES pressure compared with baseline in the rabeprazole group. In conclusion, long-term DBT could reduce acid suppression usage by enhancing the anti-reflux barrier, providing a non-pharmacological maintenance therapy and reducing medical costs for patients with GERD.

  7. Recovery of organic acids

    DOEpatents

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  8. Recovery of organic acids

    DOEpatents

    Verser, Dan W [Menlo Park, CA; Eggeman, Timothy J [Lakewood, CO

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  9. USGS Tracks Acid Rain

    USGS Publications Warehouse

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  10. Parenteral Nutrition: Amino Acids.

    PubMed

    Hoffer, Leonard John

    2017-03-10

    There is growing interest in nutrition therapies that deliver a generous amount of protein, but not a toxic amount of energy, to protein-catabolic critically ill patients. Parenteral amino acids can achieve this goal. This article summarizes the biochemical and nutritional principles that guide parenteral amino acid therapy, explains how parenteral amino acid solutions are formulated, and compares the advantages and disadvantages of different parenteral amino acid products with enterally-delivered whole protein products in the context of protein-catabolic critical illness.

  11. Parenteral Nutrition: Amino Acids

    PubMed Central

    Hoffer, Leonard John

    2017-01-01

    There is growing interest in nutrition therapies that deliver a generous amount of protein, but not a toxic amount of energy, to protein-catabolic critically ill patients. Parenteral amino acids can achieve this goal. This article summarizes the biochemical and nutritional principles that guide parenteral amino acid therapy, explains how parenteral amino acid solutions are formulated, and compares the advantages and disadvantages of different parenteral amino acid products with enterally-delivered whole protein products in the context of protein-catabolic critical illness. PMID:28287411

  12. Diterpenoid acids from Grindelia nana.

    PubMed

    Mahmoud, A A; Ahmed, A A; Tanaka, T; Iinuma, M

    2000-03-01

    Two new norditerpenoid acids of the labdane-type (norgrindelic acids), 4,5-dehydro-6-oxo-18-norgrindelic acid (1) and 4beta-hydroxy-6-oxo-19-norgrindelic acid (2), as well as a new grindelic acid derivative, 18-hydroxy-6-oxogrindelic acid (3), were isolated from the aerial parts of Grindelia nana. In addition, the known compounds, 6-oxogrindelic acid, grindelic acid, methyl grindeloate, 7alpha,8alpha-epoxygrindelic acid, and 4alpha-carboxygrindelic acid were also isolated. The structures of the new compounds were characterized on the basis of spectroscopic analysis.

  13. Structure of Acid phosphatases.

    PubMed

    Araujo, César L; Vihko, Pirkko T

    2013-01-01

    Acid phosphatases are enzymes that have been studied extensively due to the fact that their dysregulation is associated with pathophysiological conditions. This characteristic has been exploited for the development of diagnostic and therapeutic methods. As an example, prostatic acid phosphatase was the first marker for metastatic prostate cancer diagnosis and the dysregulation of tartrate resistant acid phosphatase is associated with abnormal bone resorption linked to osteoporosis. The pioneering crystallization studies on prostatic acid phosphatase and mammalian tartrate-resistant acid phosphatase conformed significant milestones towards the elucidation of the mechanisms followed by these enzymes (Schneider et al., EMBO J 12:2609-2615, 1993). Acid phosphatases are also found in nonmammalian species such as bacteria, fungi, parasites, and plants, and most of them share structural similarities with mammalian acid phosphatase enzymes. Acid phosphatase (EC 3.1.3.2) enzymes catalyze the hydrolysis of phosphate monoesters following the general equation. Phosphate monoester + H2O -->/<-- alcohol + phosphate. The general classification "acid phosphatase" relies only on the optimum acidic pH for the enzymatic activity in assay conditions using non-physiological substrates. These enzymes accept a wide range of substrates in vitro, ranging from small organic molecules to phosphoproteins, constituting a heterogeneous group of enzymes from the structural point of view. These structural differences account for the divergence in cofactor dependences and behavior against substrates, inhibitors, and activators. In this group only the tartrate-resistant acid phosphatase is a metallo-enzyme whereas the other members do not require metal-ion binding for their catalytic activity. In addition, tartrate-resistant acid phosphatase and erythrocytic acid phosphatase are not inhibited by L-(+)-tartrate ion while the prostatic acid phosphatase is tartrate-sensitive. This is an important

  14. Folic Acid and Pregnancy

    MedlinePlus

    ... Lessons? Visit KidsHealth in the Classroom What Other Parents Are Reading Your Child's Development (Birth to 3 Years) Feeding Your 1- to 3-Month-Old Feeding Your 4- to 7-Month-Old Feeding Your 8- to 12-Month-Old Feeding Your 1- to 2-Year-Old Folic Acid ... > For Parents > Folic Acid and Pregnancy A A A What's ...

  15. Bile acid transporters

    PubMed Central

    Dawson, Paul A.; Lan, Tian; Rao, Anuradha

    2009-01-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na+ taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTα-OSTβ. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers. PMID:19498215

  16. Analysis of Organic Acids.

    ERIC Educational Resources Information Center

    Griswold, John R.; Rauner, Richard A.

    1990-01-01

    Presented are the procedures and a discussion of the results for an experiment in which students select unknown carboxylic acids, determine their melting points, and investigate their solubility behavior in water and ethanol. A table of selected carboxylic acids is included. (CW)

  17. Salicylic Acid Topical

    MedlinePlus

    Propa pH® Peel-Off Acne Mask ... pimples and skin blemishes in people who have acne. Topical salicylic acid is also used to treat ... medications called keratolytic agents. Topical salicylic acid treats acne by reducing swelling and redness and unplugging blocked ...

  18. Toxicology of Perfluoroalkyl Acids*

    EPA Science Inventory

    The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

  19. Mutant fatty acid desaturase

    DOEpatents

    Shanklin, John; Cahoon, Edgar B.

    2004-02-03

    The present invention relates to a method for producing mutants of a fatty acid desaturase having a substantially increased activity towards fatty acid substrates with chains containing fewer than 18 carbons relative to an unmutagenized precursor desaturase having an 18 carbon atom chain length substrate specificity. The method involves inducing one or more mutations in the nucleic acid sequence encoding the precursor desaturase, transforming the mutated sequence into an unsaturated fatty acid auxotroph cell such as MH13 E. coli, culturing the cells in the absence of supplemental unsaturated fatty acids, thereby selecting for recipient cells which have received and which express a mutant fatty acid desaturase with an elevated specificity for fatty acid substrates having chain lengths of less than 18 carbon atoms. A variety of mutants having 16 or fewer carbon atom chain length substrate specificities are produced by this method. Mutant desaturases produced by this method can be introduced via expression vectors into prokaryotic and eukaryotic cells and can also be used in the production of transgenic plants which may be used to produce specific fatty acid products.

  20. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount of triglycerides (a fat-like ... people with very high triglycerides. Omega-3 fatty acids are in a class of medications called antilipemic ...

  1. Amino Acid Crossword Puzzle

    ERIC Educational Resources Information Center

    Sims, Paul A.

    2011-01-01

    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  2. Production of shikimic acid.

    PubMed

    Ghosh, Saptarshi; Chisti, Yusuf; Banerjee, Uttam C

    2012-01-01

    Shikimic acid is a key intermediate for the synthesis of the antiviral drug oseltamivir (Tamiflu®). Shikimic acid can be produced via chemical synthesis, microbial fermentation and extraction from certain plants. An alternative production route is via biotransformation of the more readily available quinic acid. Much of the current supply of shikimic acid is sourced from the seeds of Chinese star anise (Illicium verum). Supply from star anise seeds has experienced difficulties and is susceptible to vagaries of weather. Star anise tree takes around six-years from planting to bear fruit, but remains productive for long. Extraction and purification from seeds are expensive. Production via fermentation is increasing. Other production methods are too expensive, or insufficiently developed. In the future, production in recombinant microorganisms via fermentation may become established as the preferred route. Methods for producing shikimic acid are reviewed.

  3. Polycyclic aromatic hydrocarbon in inter-tidal mussel Perna perna: space-time observations, source investigation and genotoxicity.

    PubMed

    Francioni, E; Wagener, A de L R; Scofield, A de L; Depledge, M H; Cavalier, B; Sette, C B; Carvalhosa, L; Lozinsky, C; Mariath, R

    2007-01-01

    The investigation aimed primarily at understanding the PAH record in inter-tidal mussel tissues and evaluating the bivalve performance as a bioindicator for oil contamination. The species Perna perna was used as test organism since it is abundantly distributed in coastal areas of the Americas, Africa and elsewhere. The study was carried out in Guanabara Bay and comprised two observation phases: phase one included seasonal sampling in 8 sites, whereas in phase two 4 sites were examined over 4 years. Among the 35 determined PAH (60-90 microg kg(-1) up to 4000-6000 microg kg(-1)) alkylated homologues predominated by more than 80%. The PAH profile in inter-tidal mussels is largely petrogenic with high contribution of dibenzothiophenes (DBT) and phenanthrenes (Ph). The prevailing petrogenic fingerprint, confirmed by diagnostic ratios, is linked to the properties of the inter-tidal habitat, which favors exposure to oil films. C2DBT/C2Ph and C3DBT/C3Ph ratios, however, show a wide range of values uncorrelated to specific oils. Micronucleus frequencies are significantly related to PAH concentrations, especially to those of alkylated homologues. Genotoxic expression appears at concentrations as low as 300 microg kg(-1) summation operator 35 PAH.

  4. Adsorptive desulphurization study of liquid fuels using Tin (Sn) impregnated activated charcoal.

    PubMed

    Shah, Syed Sikandar; Ahmad, Imtiaz; Ahmad, Waqas

    2016-03-05

    Keeping in view the growing concern regarding desulphurization of petroleum products, the present study was under taken to investigate the efficiency of tin impregnated activated charcoal (Sn-AC) as a potential adsorbent for the desulphurization of model and real commercial straight run kerosene and diesel oil samples. The adsorbent Sn-AC was prepared by wet impregnation process in the laboratory and characterized by SEM, EDX and surface area analysis. Initial experiments were carried out using model oil, which was prepared by dissolving dibenzothiophene (DBT) in cyclohexane, the optimum conditions for desulfurization were found to be, 60°C temperature, 1h contact time and adsorbent dosage of 0.8g, under which about 99.4% of DBT removal was attained. Under optimized conditions the desulfurization of real oil i.e., kerosene and diesel oil was also investigated. Kinetic studies revealed that DBT adsorption followed pseudo second order kinetics and the data best fits in the Langmuir adsorption isotherm as compared to Freundlich adsorption isotherm model. The adsorbent could be easily regenerated simply by washing with toluene for a multiple cycles and reused without losing its efficiency.

  5. Biological devulcanization of ground natural rubber by Gordonia desulfuricans DSM 44462(T) strain.

    PubMed

    Tatangelo, Valeria; Mangili, Ivan; Caracino, Paola; Anzano, Manuela; Najmi, Ziba; Bestetti, Giuseppina; Collina, Elena; Franzetti, Andrea; Lasagni, Marina

    2016-10-01

    Due to the rapid increase of waste vulcanized rubber products, the development of low-cost, efficient, and selective devulcanization processes is needed. In this paper, the devulcanization ability of Gordonia desulfuricans DSM 44462(T) was evaluated by a design of experiments. The aim of the experimental design was to investigate the importance of parameters influencing the bacterial growth, such as the glucose concentration (C), dibenzothiophene concentration (DBT), and initial biomass (optical density, OD) in biodevulcanization process. The complex viscosity (η*) was chosen as experimental response for the experimental design. A multiple linear regression was used to model the relationship between the response and the process variables. In addition, the crosslink density and gel fraction were measured. Furthermore, the automated ribosomal intergenic spacer analysis (ARISA) as a microbiological method was performed to assess the persistence of the inoculated strain during the experiments. Reduced regression models were obtained considering only the significant variables and interactions. The glucose concentration C and OD variables and C-DBT and DBT-OD interactions resulted to the relevant parameters for the process. The fingerprinting showed the persistence of G. desulfuricans DSM 44462(T), despite the presence of other bacterial population after the VGNR sterilization. These results highlight the importance to support the physics analysis with microbiological analyses to evaluate the bacterial persistence during the treatment.

  6. Fatty acid production from amino acids and alpha-keto acids by Brevibacterium linens BL2.

    PubMed

    Ganesan, Balasubramanian; Seefeldt, Kimberly; Weimer, Bart C

    2004-11-01

    Low concentrations of branched-chain fatty acids, such as isobutyric and isovaleric acids, develop during the ripening of hard cheeses and contribute to the beneficial flavor profile. Catabolism of amino acids, such as branched-chain amino acids, by bacteria via aminotransferase reactions and alpha-keto acids is one mechanism to generate these flavorful compounds; however, metabolism of alpha-keto acids to flavor-associated compounds is controversial. The objective of this study was to determine the ability of Brevibacterium linens BL2 to produce fatty acids from amino acids and alpha-keto acids and determine the occurrence of the likely genes in the draft genome sequence. BL2 catabolized amino acids to fatty acids only under carbohydrate starvation conditions. The primary fatty acid end products from leucine were isovaleric acid, acetic acid, and propionic acid. In contrast, logarithmic-phase cells of BL2 produced fatty acids from alpha-keto acids only. BL2 also converted alpha-keto acids to branched-chain fatty acids after carbohydrate starvation was achieved. At least 100 genes are potentially involved in five different metabolic pathways. The genome of B. linens ATCC 9174 contained these genes for production and degradation of fatty acids. These data indicate that brevibacteria have the ability to produce fatty acids from amino and alpha-keto acids and that carbon metabolism is important in regulating this event.

  7. Total syntheses of cis-cyclopropane fatty acids: dihydromalvalic acid, dihydrosterculic acid, lactobacillic acid, and 9,10-methylenehexadecanoic acid.

    PubMed

    Shah, Sayali; White, Jonathan M; Williams, Spencer J

    2014-12-14

    cis-Cyclopropane fatty acids (cis-CFAs) are widespread constituents of the seed oils of subtropical plants, membrane components of bacteria and protozoa, and the fats and phospholipids of animals. We describe a systematic approach to the synthesis of enantiomeric pairs of four cis-CFAs: cis-9,10-methylenehexadecanoic acid, lactobacillic acid, dihydromalvalic acid, and dihydrosterculic acid. The approach commences with Rh2(OAc)4-catalyzed cyclopropenation of 1-octyne and 1-decyne, and hinges on the preparative scale chromatographic resolution of racemic 2-alkylcycloprop-2-ene-1-carboxylic acids using a homochiral Evan's auxiliary. Saturation of the individual diastereomeric N-cycloprop-2-ene-1-carbonylacyloxazolidines, followed by elaboration to alkylcyclopropylmethylsulfones, allowed Julia-Kocienski olefination with various ω-aldehyde-esters. Finally, saponification and diimide reduction afforded the individual cis-CFA enantiomers.

  8. Sulfuric Acid on Europa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain.

    This image is based on data gathered by Galileo's near infrared mapping spectrometer.

    Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks.

    Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  9. Trans Fatty Acids

    NASA Astrophysics Data System (ADS)

    Doyle, Ellin

    1997-09-01

    Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.

  10. Gluconic acid production.

    PubMed

    Anastassiadis, Savas; Morgunov, Igor G

    2007-01-01

    Gluconic acid, the oxidation product of glucose, is a mild neither caustic nor corrosive, non toxic and readily biodegradable organic acid of great interest for many applications. As a multifunctional carbonic acid belonging to the bulk chemicals and due to its physiological and chemical characteristics, gluconic acid itself, its salts (e.g. alkali metal salts, in especially sodium gluconate) and the gluconolactone form have found extensively versatile uses in the chemical, pharmaceutical, food, construction and other industries. Present review article presents the comprehensive information of patent bibliography for the production of gluconic acid and compares the advantages and disadvantages of known processes. Numerous manufacturing processes are described in the international bibliography and patent literature of the last 100 years for the production of gluconic acid from glucose, including chemical and electrochemical catalysis, enzymatic biocatalysis by free or immobilized enzymes in specialized enzyme bioreactors as well as discontinuous and continuous fermentation processes using free growing or immobilized cells of various microorganisms, including bacteria, yeast-like fungi and fungi. Alternatively, new superior fermentation processes have been developed and extensively described for the continuous and discontinuous production of gluconic acid by isolated strains of yeast-like mold Aureobasidium pullulans, offering numerous advantages over the traditional discontinuous fungi processes.

  11. Strongly Acidic Auxin Indole-3-Methanesulfonic Acid

    PubMed Central

    Cohen, Jerry D.; Baldi, Bruce G.; Bialek, Krystyna

    1985-01-01

    A radiochemical synthesis is described for [14C]indole-3-methanesulfonic acid (IMS), a strongly acidic auxin analog. Techniques were developed for fractionation and purification of IMS using normal and reverse phase chromatography. In addition, the utility of both Fourier transform infrared spectrometry and fast atom bombardment mass spectrometry for analysis of IMS has been demonstrated. IMS was shown to be an active auxin, stimulating soybean hypocotyl elongation, bean first internode curvature, and ethylene production. IMS uptake by thin sections of soybean hypocotyl was essentially independent of solution pH and, when applied at a 100 micromolar concentration, IMS exhibited a basipetal polarity in its transport in both corn coleoptile and soybean hypocotyl sections. [14C]IMS should, therefore, be a useful compound to study fundamental processes related to the movement of auxins in plant tissues and organelles. PMID:16664007

  12. Aminolevulinic Acid Topical

    MedlinePlus

    ... under the skin that result from exposure to sunlight and can develop into skin cancer) of the ... acid will make your skin very sensitive to sunlight (likely to get sunburn). Avoid exposure of treated ...

  13. Difficult Decisions: Acid Rain.

    ERIC Educational Resources Information Center

    Miller, John A.; Slesnick, Irwin L.

    1989-01-01

    Discusses some of the contributing factors and chemical reactions involved in the production of acid rain, its effects, and political issues pertaining to who should pay for the clean up. Supplies questions for consideration and discussion. (RT)

  14. Folic acid - test

    MedlinePlus

    ... folic acid before and during pregnancy helps prevent neural tube defects, such as spina bifida. Women who ... take more if they have a history of neural tube defects in earlier pregnancies. Ask your provider ...

  15. Acid soldering flux poisoning

    MedlinePlus

    The harmful substances in soldering fluxes are called hydrocarbons. They include: Ammonium chloride Rosin Hydrochloric acid Zinc ... Lee DC. Hydrocarbons. In: Marx JA, Hockberger RS, Walls RM, et ... Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ...

  16. Amoxicillin and Clavulanic Acid

    MedlinePlus

    ... Amoxicillin is in a class of medications called penicillin-like antibiotics. It works by stopping the growth ... allergic to amoxicillin (Amoxil, Trimox, Wymox), clavulanic acid, penicillin, cephalosporins, or any other medications.tell your doctor ...

  17. Amino Acid Metabolism Disorders

    MedlinePlus

    ... acidemia? In ASA, the body can’t remove ammonia or a substance called argininosuccinic acid from the ... and children include: Breathing problems High levels of ammonia in the bloodIntense headache, especially after a high- ...

  18. [Hydrofluoric acid burns].

    PubMed

    Holla, Robin; Gorter, Ramon R; Tenhagen, Mark; Vloemans, A F P M Jos; Breederveld, Roelf S

    2016-01-01

    Hydrofluoric acid is increasingly used as a rust remover and detergent. Dermal contact with hydrofluoric acid results in a chemical burn characterized by severe pain and deep tissue necrosis. It may cause electrolyte imbalances with lethal consequences. It is important to identify high-risk patients. 'High risk' is defined as a total affected body area > 3% or exposure to hydrofluoric acid in a concentration > 50%. We present the cases of three male patients (26, 31, and 39 years old) with hydrofluoric acid burns of varying severity and describe the subsequent treatments. The application of calcium gluconate 2.5% gel to the skin is the cornerstone of the treatment, reducing pain as well as improving wound healing. Nails should be thoroughly inspected and possibly removed if the nail is involved, to ensure proper healing. In high-risk patients, plasma calcium levels should be evaluated and cardiac monitoring is indicated.

  19. Citric acid urine test

    MedlinePlus

    ... used to diagnose renal tubular acidosis and evaluate kidney stone disease. Normal Results The normal range is 320 ... tubular acidosis and a tendency to form calcium kidney stones. The following may decrease urine citric acid levels: ...

  20. Lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Bullock, Kathryn R.

    Lead/acid batteries are produced in sizes from less than 1 to 3000 Ah for a wide variety of portable, industrial and automotive applications. Designs include Planté, Fauré or pasted, and tubular electrodes. In addition to the traditional designs which are flooded with sulfuric acid, newer 'valve-regulated" designs have the acid immolibized in a silica gel or absorbed in a porous glass separator. Development is ongoing worldwide to increase the specific power, energy and deep discharge cycle life of this commercially successful system to meet the needs of new applications such as electric vehicles, load leveling, and solar energy storage. The operating principles, current status, technical challenges and commercial impact of the lead/acid battery are reviewed.

  1. Amino Acids and Chirality

    NASA Technical Reports Server (NTRS)

    Cook, Jamie E.

    2012-01-01

    Amino acids are among the most heavily studied organic compound class in carbonaceous chondrites. The abundance, distributions, enantiomeric compositions, and stable isotopic ratios of amino acids have been determined in carbonaceous chondrites fi'om a range of classes and petrographic types, with interesting correlations observed between these properties and the class and typc of the chondritcs. In particular, isomeric distributions appear to correlate with parent bodies (chondrite class). In addition, certain chiral amino acids are found in enantiomeric excess in some chondrites. The delivery of these enantiomeric excesses to the early Earth may have contributed to the origin of the homochirality that is central to life on Earth today. This talk will explore the amino acids in carbonaceous chondritcs and their relevance to the origin of life.

  2. The linoleic acid and trans fatty acids of margarines.

    PubMed

    Beare-Rogers, J L; Gray, L M; Hollywood, R

    1979-09-01

    Fifty brands of margarine were analysed for cis-polyunsaturated acids by lipoxidase, for trans fatty acid by infared spectroscopy, and for fatty acid composition by gas-liquid chromatography. High concentrations of trans fatty acids tended to be associated with low concentrations of linoleic acid. Later analyses on eight of the brands, respresenting various proportions of linoleic to trans fatty acids, indicated that two of them contained still higher levels of trans fatty acids (greater than 60%) and negligible amounts of linoleic acid. It is proposed that margarine could be a vehicle for the distribution of some dietary linoleic acid and that the level of linoleic acid and the summation of the saturated plus trans fatty acids be known to ascertain nutritional characteristics.

  3. Method for isolating nucleic acids

    SciTech Connect

    Hurt, Jr., Richard Ashley; Elias, Dwayne A.

    2015-09-29

    The current disclosure provides methods and kits for isolating nucleic acid from an environmental sample. The current methods and compositions further provide methods for isolating nucleic acids by reducing adsorption of nucleic acids by charged ions and particles within an environmental sample. The methods of the current disclosure provide methods for isolating nucleic acids by releasing adsorbed nucleic acids from charged particles during the nucleic acid isolation process. The current disclosure facilitates the isolation of nucleic acids of sufficient quality and quantity to enable one of ordinary skill in the art to utilize or analyze the isolated nucleic acids for a wide variety of applications including, sequencing or species population analysis.

  4. [Acids in coffee. XI. The proportion of individual acids in the total titratable acid].

    PubMed

    Engelhardt, U H; Maier, H G

    1985-07-01

    22 acids in ground roast coffees and instant coffees were determined by GLC of their silyl derivatives (after preseparation by gel electrophoresis) or isotachophoresis. The contribution to the total acidity (which was estimated by titration to pH 8 after cation exchange of the coffee solutions) was calculated for each individual acid. The mentioned acids contribute with 67% (roast coffee) and 72% (instant coffee) to the total acidity. In the first place citric acid (12.2% in roast coffee/10.7% in instant coffee), acetic acid (11.2%/8.8%) and the high molecular weight acids (8%/9%) contribute to the total acidity. Also to be mentioned are the shares of chlorogenic acids (9%/4.8%), formic acid (5.3%/4.6%), quinic acid (4.7%/5.9%), malic acid (3.9%/3%) and phosphoric acid (2.5%/5.2%). A notable difference in the contribution to total acidity between roast and instant coffee was found for phosphoric acid and pyrrolidonecarboxylic acid (0.7%/1.9%). It can be concluded that those two acids are formed or released from e.g. their esters in higher amounts than other acids during the production of instant coffee.

  5. Acidification and Acid Rain

    NASA Astrophysics Data System (ADS)

    Norton, S. A.; Veselã½, J.

    2003-12-01

    Air pollution by acids has been known as a problem for centuries (Ducros, 1845; Smith, 1872; Camuffo, 1992; Brimblecombe, 1992). Only in the mid-1900s did it become clear that it was a problem for more than just industrially developed areas, and that precipitation quality can affect aquatic resources ( Gorham, 1955). The last three decades of the twentieth century saw tremendous progress in the documentation of the chemistry of the atmosphere, precipitation, and the systems impacted by acid atmospheric deposition. Chronic acidification of ecosystems results in chemical changes to soil and to surface waters and groundwater as a result of reduction of base cation supply or an increase in acid (H+) supply, or both. The most fundamental changes during chronic acidification are an increase in exchangeable H+ or Al3+ (aluminum) in soils, an increase in H+ activity (˜concentration) in water in contact with soil, and a decrease in alkalinity in waters draining watersheds. Water draining from the soil is acidified and has a lower pH (=-log [H+]). As systems acidify, their biotic community changes.Acidic surface waters occur in many parts of the world as a consequence of natural processes and also due to atmospheric deposition of strong acid (e.g., Canada, Jeffries et al. (1986); the United Kingdom, Evans and Monteith (2001); Sweden, Swedish Environmental Protection Board (1986); Finland, Forsius et al. (1990); Norway, Henriksen et al. (1988a); and the United States (USA), Brakke et al. (1988)). Concern over acidification in the temperate regions of the northern hemisphere has been driven by the potential for accelerating natural acidification by pollution of the atmosphere with acidic or acidifying compounds. Atmospheric pollution ( Figure 1) has resulted in an increased flux of acid to and through ecosystems. Depending on the ability of an ecosystem to neutralize the increased flux of acidity, acidification may increase only imperceptibly or be accelerated at a rate that

  6. The second acidic constant of salicylic acid.

    PubMed

    Porto, Raffaella; De Tommaso, Gaetano; Furia, Emilia

    2005-01-01

    The second dissociation constant of salicylic acid (H2L) has been determined, at 25 degrees C, in NaCl ionic media by UV spectrophotometric measurements. The investigated ionic strength values were 0.16, 0.25, 0.50, 1.0, 2.0 and 3.0 M. The protolysis constants calculated at the different ionic strengths yielded, with the Specific Interaction Theory, the infinite dilution constant, log beta1(0) = 13.62 +/- 0.03, for the equilibrium L2- + H+ <==> HL-. The interaction coefficient between Na+ and L2-, b(Na+, L2-) = 0.02 +/- 0.07, has been also calculated.

  7. Differential activation of pregnane X receptor by carnosic acid, carnosol, ursolic acid, and rosmarinic acid.

    PubMed

    Seow, Chun Ling; Lau, Aik Jiang

    2017-03-10

    Pregnane X receptor (PXR) regulates the expression of many genes, including those involved in drug metabolism and transport, and has been linked to various diseases, including inflammatory bowel disease. In the present study, we determined whether carnosic acid and other chemicals in rosemary extract (carnosol, ursolic acid, and rosmarinic acid) are PXR activators. As assessed in dual-luciferase reporter gene assays, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, activated human PXR (hPXR) and mouse PXR (mPXR), whereas carnosol and ursolic acid, but not carnosic acid or rosmarinic acid, activated rat PXR (rPXR). Dose-response experiments indicated that carnosic acid, carnosol, and ursolic acid activated hPXR with EC50 values of 0.79, 2.22, and 10.77μM, respectively. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, transactivated the ligand-binding domain of hPXR and recruited steroid receptor coactivator-1 (SRC-1), SRC-2, and SRC-3 to the ligand-binding domain of hPXR. Carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, increased hPXR target gene expression, as shown by an increase in CYP3A4, UGT1A3, and ABCB1 mRNA expression in LS180 human colon adenocarcinoma cells. Rosmarinic acid did not attenuate the extent of hPXR activation by rifampicin, suggesting it is not an antagonist of hPXR. Overall, carnosic acid, carnosol, and ursolic acid, but not rosmarinic acid, are hPXR agonists, and carnosic acid shows species-dependent activation of hPXR and mPXR, but not rPXR. The findings provide new mechanistic insight on the effects of carnosic acid, carnosol, and ursolic acid on PXR-mediated biological effects.

  8. Discovery of essential fatty acids

    PubMed Central

    Spector, Arthur A.; Kim, Hee-Yong

    2015-01-01

    Dietary fat was recognized as a good source of energy and fat-soluble vitamins by the first part of the 20th century, but fatty acids were not considered to be essential nutrients because they could be synthesized from dietary carbohydrate. This well-established view was challenged in 1929 by George and Mildred Burr who reported that dietary fatty acid was required to prevent a deficiency disease that occurred in rats fed a fat-free diet. They concluded that fatty acids were essential nutrients and showed that linoleic acid prevented the disease and is an essential fatty acid. The Burrs surmised that other unsaturated fatty acids were essential and subsequently demonstrated that linolenic acid, the omega-3 fatty acid analog of linoleic acid, is also an essential fatty acid. The discovery of essential fatty acids was a paradigm-changing finding, and it is now considered to be one of the landmark discoveries in lipid research. PMID:25339684

  9. Acid Rain, pH & Acidity: A Common Misinterpretation.

    ERIC Educational Resources Information Center

    Clark, David B.; Thompson, Ronald E.

    1989-01-01

    Illustrates the basis for misleading statements about the relationship between pH and acid content in acid rain. Explains why pH cannot be used as a measure of acidity for rain or any other solution. Suggests that teachers present acidity and pH as two separate and distinct concepts. (RT)

  10. [Lipid synthesis by an acidic acid tolerant Rhodotorula glutinis].

    PubMed

    Lin, Zhangnan; Liu, Hongjuan; Zhang, Jian'an; Wang, Gehua

    2016-03-01

    Acetic acid, as a main by-product generated in the pretreatment process of lignocellulose hydrolysis, significantly affects cell growth and lipid synthesis of oleaginous microorganisms. Therefore, we studied the tolerance of Rhodotorula glutinis to acetic acid and its lipid synthesis from substrate containing acetic acid. In the mixed sugar medium containing 6 g/L glucose and 44 g/L xylose, and supplemented with acetic acid, the cell growth was not:inhibited when the acetic acid concentration was below 10 g/L. Compared with the control, the biomass, lipid concentration and lipid content of R. glutinis increased 21.5%, 171% and 122% respectively when acetic acid concentration was 10 g/L. Furthermore, R. glutinis could accumulate lipid with acetate as the sole carbon source. Lipid concentration and lipid yield reached 3.20 g/L and 13% respectively with the initial acetic acid concentration of 25 g/L. The lipid composition was analyzed by gas chromatograph. The main composition of lipid produced with acetic acid was palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid, including 40.9% saturated fatty acids and 59.1% unsaturated fatty acids. The lipid composition was similar to that of plant oil, indicating that lipid from oleaginous yeast R. glutinis had potential as the feedstock of biodiesel production. These results demonstrated that a certain concentration of acetic acid need not to be removed in the detoxification process when using lignocelluloses hydrolysate to produce microbial lipid by R. glutinis.

  11. Amino-acid contamination of aqueous hydrochloric acid.

    NASA Technical Reports Server (NTRS)

    Wolman, Y.; Miller, S. L.

    1971-01-01

    Considerable amino-acid contamination in commercially available analytical grade hydrochloric acid (37% HCl) was found. One bottle contained 8,300 nmol of amino-acids per liter. A bottle from another supplier contained 6,700 nmol per liter. The contaminants were mostly protein amino-acids and several unknowns. Data on the volatility of the amino-acids during HCl distillation were also obtained.

  12. Recurrent uric acid stones.

    PubMed

    Kamel, K S; Cheema-Dhadli, S; Shafiee, M A; Davids, M R; Halperin, M L

    2005-01-01

    A 46-year-old female had a history of recurrent uric acid stone formation, but the reason why uric acid precipitated in her urine was not obvious, because the rate of urate excretion was not high, urine volume was not low, and the pH in her 24-h urine was not low enough. In his discussion of the case, Professor McCance provided new insights into the pathophysiology of uric acid stone formation. He illustrated that measuring the pH in a 24-h urine might obscure the fact that the urine pH was low enough to cause uric acid to precipitate during most of the day. Because he found a low rate of excretion of NH(4)(+) relative to that of sulphate anions, as well as a high rate of citrate excretion, he speculated that the low urine pH would be due to a more alkaline pH in proximal convoluted tubule cells. He went on to suspect that there was a problem in our understanding of the function of renal medullary NH(3) shunt pathway, and he suggested that its major function might be to ensure a urine pH close to 6.0 throughout the day, to minimize the likelihood of forming uric acid kidney stones.

  13. Hydrogen production by fermentation using acetic acid and lactic acid.

    PubMed

    Matsumoto, Mitsufumi; Nishimura, Yasuhiko

    2007-03-01

    Microbial hydrogen production from sho-chu post-distillation slurry solution (slurry solution) containing large amounts of organic acids was investigated. The highest hydrogen producer, Clostridium diolis JPCC H-3, was isolated from natural environment and produced hydrogen at 6.03+/-0.15 ml from 5 ml slurry solution in 30 h. Interestingly, the concentration of acetic acid and lactic acid in the slurry solution decreased during hydrogen production. The substrates for hydrogen production by C. diolis JPCC H-3, in particular organic acids, were investigated in an artificial medium. No hydrogen was produced from acetic acid, propionic acid, succinic acid, or citric acid on their own. Hydrogen and butyric acid were produced from a mixture of acetic acid and lactic acid, showing that C. diolis. JPCC H-3 could produce hydrogen from acetic acid and lactic acid. Furthermore, calculation of the Gibbs free energy strongly suggests that this reaction would proceed. In this paper, we describe for the first time microbial hydrogen production from acetic acid and lactic acid by fermentation.

  14. A Demonstration of Acid Rain

    ERIC Educational Resources Information Center

    Fong, Man Wai

    2004-01-01

    A demonstration showing acid rain formation is described. Oxides of sulfur and nitrogen that result from the burning of fossil fuels are the major pollutants of acid rain. In this demonstration, SO[subscript 2] gas is produced by the burning of matches. An acid-base indicator will show that the dissolved gas turns an aqueous solution acidic.

  15. Biodegradation of Cyanuric Acid

    PubMed Central

    Saldick, Jerome

    1974-01-01

    Cyanuric acid biodegrades readily under a wide variety of natural conditions, and particularly well in systems of either low or zero dissolved-oxygen level, such as anaerobic activated sludge and sewage, soils, muds, and muddy streams and river waters, as well as ordinary aerated activated sludge systems with typically low (1 to 3 ppm) dissolved-oxygen levels. Degradation also proceeds in 3.5% sodium chloride solution. Consequently, there are degradation pathways widely available for breaking down cyanuric acid discharged in domestic effluents. The overall degradation reaction is merely a hydrolysis; CO2 and ammonia are the initial hydrolytic breakdown products. Since no net oxidation occurs during this breakdown, biodegradation of cyanuric acid exerts no primary biological oxygen demand. However, eventual nitrification of the ammonia released will exert its usual biological oxygen demand. PMID:4451360

  16. [Aristolochic acid nephropathy].

    PubMed

    Witkowicz, Joanna

    2009-01-01

    Aristolochic acid nephropathy is a chronic, fibrosing, interstitial nephritis caused by aristolochic acid (AA), which is a component of the plants of Aristolochiacae family. It was first reported in 1993, in Belgium as a Chinese herb nephropathy, in patients who received a slimming regimen containing AA. The term aristolochic acid nephropathy also includes Balcan endemic nephropathy and other endemic tubulointerstitial fibrosis. Moreover, AA is a human carcinogen which induces urothelial cancer. The AA-containing herbs are banned in many countries and FDA published the warnings concerning the safety of AA-containing botanical remedies in 2000. Regarding the increasing interest in herbal medicines, uncontrolled access to botanical remedies and replacement of one herb by another AA-containing compounds makes thousands of people all around the world at risk of this grave disease.

  17. Calorimetry of Nucleic Acids.

    PubMed

    Rozners, Eriks; Pilch, Daniel S; Egli, Martin

    2015-12-01

    This unit describes the application of calorimetry to characterize the thermodynamics of nucleic acids, specifically, the two major calorimetric methodologies that are currently employed: differential scanning (DSC) and isothermal titration calorimetry (ITC). DSC is used to study thermally induced order-disorder transitions in nucleic acids. A DSC instrument measures, as a function of temperature (T), the excess heat capacity (C(p)(ex)) of a nucleic acid solution relative to the same amount of buffer solution. From a single curve of C(p)(ex) versus T, one can derive the following information: the transition enthalpy (ΔH), entropy (ΔS), free energy (ΔG), and heat capacity (ΔCp); the state of the transition (two-state versus multistate); and the average size of the molecule that melts as a single thermodynamic entity (e.g., the duplex). ITC is used to study the hybridization of nucleic acid molecules at constant temperature. In an ITC experiment, small aliquots of a titrant nucleic acid solution (strand 1) are added to an analyte nucleic acid solution (strand 2), and the released heat is monitored. ITC yields the stoichiometry of the association reaction (n), the enthalpy of association (ΔH), the equilibrium association constant (K), and thus the free energy of association (ΔG). Once ΔH and ΔG are known, ΔS can also be derived. Repetition of the ITC experiment at a number of different temperatures yields the ΔCp for the association reaction from the temperature dependence of ΔH.

  18. Acid rain in Asia

    NASA Astrophysics Data System (ADS)

    Bhatti, Neeloo; Streets, David G.; Foell, Wesley K.

    1992-07-01

    Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.

  19. Ethylenediaminetetraacetic acid in endodontics.

    PubMed

    Mohammadi, Zahed; Shalavi, Sousan; Jafarzadeh, Hamid

    2013-09-01

    Ethylenediaminetetraacetic acid (EDTA) is a chelating agent can bind to metals via four carboxylate and two amine groups. It is a polyamino carboxylic acid and a colorless, water-soluble solid, which is widely used to dissolve lime scale. It is produced as several salts, notably disodium EDTA and calcium disodium EDTA. EDTA reacts with the calcium ions in dentine and forms soluble calcium chelates. A review of the literature and a discussion of the different indications and considerations for its usage are presented.

  20. Ethylenediaminetetraacetic acid in endodontics

    PubMed Central

    Mohammadi, Zahed; Shalavi, Sousan; Jafarzadeh, Hamid

    2013-01-01

    Ethylenediaminetetraacetic acid (EDTA) is a chelating agent can bind to metals via four carboxylate and two amine groups. It is a polyamino carboxylic acid and a colorless, water-soluble solid, which is widely used to dissolve lime scale. It is produced as several salts, notably disodium EDTA and calcium disodium EDTA. EDTA reacts with the calcium ions in dentine and forms soluble calcium chelates. A review of the literature and a discussion of the different indications and considerations for its usage are presented. PMID:24966721

  1. The Acid-Base Titration of a Very Weak Acid: Boric Acid

    ERIC Educational Resources Information Center

    Celeste, M.; Azevedo, C.; Cavaleiro, Ana M. V.

    2012-01-01

    A laboratory experiment based on the titration of boric acid with strong base in the presence of d-mannitol is described. Boric acid is a very weak acid and direct titration with NaOH is not possible. An auxiliary reagent that contributes to the release of protons in a known stoichiometry facilitates the acid-base titration. Students obtain the…

  2. Comparison of Buffer Effect of Different Acids During Sandstone Acidizing

    NASA Astrophysics Data System (ADS)

    Umer Shafiq, Mian; Khaled Ben Mahmud, Hisham; Hamid, Mohamed Ali

    2015-04-01

    The most important concern of sandstone matrix acidizing is to increase the formation permeability by removing the silica particles. To accomplish this, the mud acid (HF: HCl) has been utilized successfully for many years to stimulate the sandstone formations, but still it has many complexities. This paper presents the results of laboratory investigations of different acid combinations (HF: HCl, HF: H3PO4 and HF: HCOOH). Hydrofluoric acid and fluoboric acid are used to dissolve clays and feldspar. Phosphoric and formic acids are added as a buffer to maintain the pH of the solution; also it allows the maximum penetration of acid into the core sample. Different tests have been performed on the core samples before and after the acidizing to do the comparative study on the buffer effect of these acids. The analysis consists of permeability, porosity, color change and pH value tests. There is more increase in permeability and porosity while less change in pH when phosphoric and formic acids were used compared to mud acid. From these results it has been found that the buffer effect of phosphoric acid and formic acid is better than hydrochloric acid.

  3. Oxalic acid excretion after intravenous ascorbic acid administration.

    PubMed

    Robitaille, Line; Mamer, Orval A; Miller, Wilson H; Levine, Mark; Assouline, Sarit; Melnychuk, David; Rousseau, Caroline; Hoffer, L John

    2009-02-01

    Ascorbic acid is frequently administered intravenously by alternative health practitioners and, occasionally, by mainstream physicians. Intravenous administration can greatly increase the amount of ascorbic acid that reaches the circulation, potentially increasing the risk of oxalate crystallization in the urinary space. To investigate this possibility, we developed gas chromatography mass spectrometry methodology and sampling and storage procedures for oxalic acid analysis without interference from ascorbic acid and measured urinary oxalic acid excretion in people administered intravenous ascorbic acid in doses ranging from 0.2 to 1.5 g/kg body weight. In vitro oxidation of ascorbic acid to oxalic acid did not occur when urine samples were brought immediately to pH less than 2 and stored at -30 degrees C within 6 hours. Even very high ascorbic acid concentrations did not interfere with the analysis when oxalic acid extraction was carried out at pH 1. As measured during and over the 6 hours after ascorbic acid infusions, urinary oxalic acid excretion increased with increasing doses, reaching approximately 80 mg at a dose of approximately 100 g. We conclude that, when studied using correct procedures for sample handling, storage, and analysis, less than 0.5% of a very large intravenous dose of ascorbic acid is recovered as urinary oxalic acid in people with normal renal function.

  4. [Studies on interaction of acid-treated nanotube titanic acid and amino acids].

    PubMed

    Zhang, Huqin; Chen, Xuemei; Jin, Zhensheng; Liao, Guangxi; Wu, Xiaoming; Du, Jianqiang; Cao, Xiang

    2010-06-01

    Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination.

  5. Research on Identification and Screen of Microbial Desulfurization Strains for Petroleum

    NASA Astrophysics Data System (ADS)

    Xiaojuan, Tian; Lingtian, Tang; Li'e, Peng; Xinghong, Li

    The oil-contaminated soil sample was acquired from Shengli Oilfield and Jidong Oilfield and cultured with enrichment technology. Then 21 desulfurization strains were separated from the sample, from which a high efficiency desulfurization strain TV9704 was selected. The strain could neither grow with n-dodecane, n-hexadecane, liquid paraffin, naphthalene or diesel as a carbon source and energy source, nor obviously reduce oil combustion value. It could use thiophene or dibenzothiophene (DBT) as the sole sulfur source. In the experiment, the concentrations of thiophene and DBT were measured by UV spectrophotometer. After being cultured in the culture medium with an initial concentration of 63.2 mmol/L respectively for 48 h and 144 h, the degradation rates of the strain TV9704 on thiophene were 39.0% and 63.8%; the DBT with an initial concentration of 2.7 mmol/L was degraded by 1.46 mmol/L after cultured for 72 h. When sodium acetate and glycerol were chosen as carbon source, the ethanol could enhance the degradation rate of TV9704 on DBT significantly. Strain TV9704 was identified by China Industrial Culture Collection Center (CICC) as a Bacillus sp., Gram-positive, obligate aerobic, which forms a circular orange colony on the nutrition gravy plate. The 16SrDNA gene sequencing test and analysis was carried out on strain TV9704, finding that its homologies with the most similar species Bacillus aquimaris and Bacillus marisflavi were 99.2% and 98.2% respectively, but a larger difference existed between their cell morphological characteristics and physiological and biochemical characteristics, therefore strain TV9704 may be a new species because it was impossible to be categorized to any population.

  6. Alkyl phosphonic acids and sulfonic acids in the Murchison meteorite

    NASA Technical Reports Server (NTRS)

    Cooper, George W.; Onwo, Wilfred M.; Cronin, John R.

    1992-01-01

    Homologous series of alkyl phosphonic acids and alkyl sulfonic acids, along with inorganic orthophosphate and sulfate, are identified in water extracts of the Murchison meteorite after conversion to their t-butyl dimethylsilyl derivatives. The methyl, ethyl, propyl, and butyl compounds are observed in both series. Five of the eight possible alkyl phosphonic acids and seven of the eight possible alkyl sulfonic acids through C4 are identified. Abundances decrease with increasing carbon number as observed of other homologous series indigenous to Murchison. Concentrations range downward from approximately 380 nmol/gram in the alkyl sulfonic acid series, and from 9 nmol/gram in the alkyl phosphonic acid series.

  7. Effect of domoic acid on brain amino acid levels.

    PubMed

    Durán, R; Arufe, M C; Arias, B; Alfonso, M

    1995-03-01

    The administration of Domoic Acid (Dom) in a 0.2 mg/kg i.p. dose induces changes in the levels of amino acids of neurochemical interest (Asp, Glu, Gly, Tau, Ala, GABA) in different rat brain regions (hypothalamus, hippocampus, amygdala, striatum, cortex and midbrain). The most affected amino acid is the GABA, the main inhibitory amino acid neurotransmitter, whereas glutamate, the main excitatory amino acid, is not affected. The rat brain regions that seem to be the main target of the Dom action belong to the limbic system (hippocampus, amygdala). The possible implication of the amino acids in the actions of Dom is also discussed.

  8. Hydrofluoric acid poisoning

    MedlinePlus

    Chemical Emergencies: Case Definition: Hydrofluoric Acid . Centers for Disease Control and Prevention, U.S. Dept of Health and Human Services; 2005. Goldfrank LR, ed. Goldfrank's Toxicologic Emergencies . 8th ed. New York, NY: McGraw Hill; 2006. Wax PM, Young A. ...

  9. Plant fatty acid hydroxylase

    DOEpatents

    Somerville, Chris; van de Loo, Frank

    2000-01-01

    The present invention relates to the identification of nucleic acid sequences and constructs, and methods related thereto, and the use of these sequences and constructs to produce genetically modified plants for the purpose of altering the composition of plant oils, waxes and related compounds.

  10. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Oates-Bockenstedt, Catherine

    1997-01-01

    Details an activity designed to motivate students by incorporating science-related issues into a classroom debate. Includes "The Acid Rain Bill" and "Position Guides" for student roles as committee members, consumers, governors, industry owners, tourism professionals, senators, and debate directors. (DKM)

  11. Acid Rain Investigations.

    ERIC Educational Resources Information Center

    Hugo, John C.

    1992-01-01

    Presents an activity in which students investigate the formation of solid ammonium chloride aerosol particles to help students better understand the concept of acid rain. Provides activity objectives, procedures, sample data, clean-up instructions, and questions and answers to help interpret the data. (MDH)

  12. The Acid Rain Game.

    ERIC Educational Resources Information Center

    Rakow, Steven J.; Glenn, Allen

    1982-01-01

    Provides rationale for and description of an acid rain game (designed for two players), a problem-solving model for elementary students. Although complete instructions are provided, including a copy of the game board, the game is also available for Apple II microcomputers. Information for the computer program is available from the author.…

  13. Acid Rain Classroom Projects.

    ERIC Educational Resources Information Center

    Demchik, Michael J.

    2000-01-01

    Describes a curriculum plan in which students learn about acid rain through instructional media, research and class presentations, lab activities, simulations, design, and design implementation. Describes the simulation activity in detail and includes materials, procedures, instructions, examples, results, and discussion sections. (SAH)

  14. The Acid Rain Debate.

    ERIC Educational Resources Information Center

    Bybee, Rodger; And Others

    1984-01-01

    Describes an activity which provides opportunities for role-playing as industrialists, ecologists, and government officials. The activity involves forming an international commission on acid rain, taking testimony, and, based on the testimony, making recommendations to governments on specific ways to solve the problem. Includes suggestions for…

  15. Acid rain bibliography

    SciTech Connect

    Sayers, C.S.

    1983-09-01

    This bibliography identifies 900 citations on various aspects of Acid Rain, covering published bibliographies, books, reports, conference and symposium proceedings, audio visual materials, pamphlets and newsletters. It includes five sections: citations index (complete record of author, title, source, order number); KWIC index; title index; author index; and source index. 900 references.

  16. Docosahexaenoic acid and lactation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Docosahexaenoic acid (DHA) is an important component of membrane phospholipids in the retina, and brain, and accumulates rapidly in these tissues during early infancy. DHA is present in human milk, but the amount varies considerably and is largely dependent on maternal diet. This article reviews dat...

  17. Spermatotoxicity of dichloroacetic acid

    EPA Science Inventory

    The testicular toxicity of dichloroacetic acid (DCA), a disinfection byproduct of drinking water, was evaluated in adult male rats given both single and multiple (up to 14 d) oral doses. Delayed spermiation and altered resorption of residual bodies were observed in rats given sin...

  18. Water surface is acidic

    PubMed Central

    Buch, Victoria; Milet, Anne; Vácha, Robert; Jungwirth, Pavel; Devlin, J. Paul

    2007-01-01

    Water autoionization reaction 2H2O → H3O− + OH− is a textbook process of basic importance, resulting in pH = 7 for pure water. However, pH of pure water surface is shown to be significantly lower, the reduction being caused by proton stabilization at the surface. The evidence presented here includes ab initio and classical molecular dynamics simulations of water slabs with solvated H3O+ and OH− ions, density functional studies of (H2O)48H+ clusters, and spectroscopic isotopic-exchange data for D2O substitutional impurities at the surface and in the interior of ice nanocrystals. Because H3O+ does, but OH− does not, display preference for surface sites, the H2O surface is predicted to be acidic with pH < 4.8. For similar reasons, the strength of some weak acids, such as carbonic acid, is expected to increase at the surface. Enhanced surface acidity can have a significant impact on aqueous surface chemistry, e.g., in the atmosphere. PMID:17452650

  19. Acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1984-01-01

    Discusses the problem of acid rain and how it can be controlled. The book is divided into seven key sections: the problem and the legislative solutions; international mitigation programs; planning the US program; emissions reduction-before combustion; emissions/reduction-during combustion; emissions reduction-after combustion and engineering solutions under development. 13 papers have been abstracted separately.

  20. The acid rain sourcebook

    SciTech Connect

    Elliott, T.C.; Schwieger, R.G.

    1985-01-01

    A reference collection of specialized information discussions on areas critical to the acid rain issue: problem definition, impact of legislation, emissions standards, international perspective, cost scenarios, and engineering solutions. The text is reinforced with 130 illustrations and about 50 tables. Contents: International mitigation programs. Emissions reduction: before combustion; during combustion; after combustion. Engineering solutions under development.

  1. A Direct, Biomass-Based Synthesis of Benzoic Acid: Formic Acid-Mediated Deoxygenation of the Glucose-Derived Materials Quinic Acid and Shikimic Acid

    SciTech Connect

    Arceo, Elena; Ellman, Jonathan; Bergman, Robert

    2010-05-03

    An alternative biomass-based route to benzoic acid from the renewable starting materials quinic acid and shikimic acid is described. Benzoic acid is obtained selectively using a highly efficient, one-step formic acid-mediated deoxygenation method.

  2. Synthesis of acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters

    DOEpatents

    Moens, Luc

    2003-06-24

    A process of preparing an acid addition salt of delta-aminolevulinc acid comprising: a) dissolving a lower alkyl 5-bromolevulinate and hexamethylenetetramine in a solvent selected from the group consisting of water, ethyl acetate, chloroform, acetone, ethanol, tetrahydrofuran and acetonitrile, to form a quaternary ammonium salt of the lower alkyl 5-bromolevulinate; and b) hydrolyzing the quaternary ammonium salt with an inorganic acid to form an acid addition salt of delta-aminolevulinic acid.

  3. Photostabilization of ascorbic acid with citric acid, tartaric acid and boric acid in cream formulations.

    PubMed

    Ahmad, I; Ali Sheraz, M; Ahmed, S; Shad, Z; Vaid, F H M

    2012-06-01

    This study involves the evaluation of the effect of certain stabilizers, that is, citric acid (CT), tartaric acid (TA) and boric acid (BA) on the degradation of ascorbic acid (AH(2) ) in oil-in-water cream formulations exposed to the UV light and stored in the dark. The apparent first-order rate constants (0.34-0.95 × 10(-3) min(-1) in light, 0.38-1.24 × 10(-2) day(-1) in dark) for the degradation reactions in the presence of the stabilizers have been determined. These rate constants have been used to derive the second-order rate constants (0.26-1.45 × 10(-2) M(-1) min(-1) in light, 3.75-8.50 × 10(-3) M(-1) day(-1) in dark) for the interaction of AH(2) and the individual stabilizers. These stabilizers are effective in causing the inhibition of the rate of degradation of AH(2) both in the light and in the dark. The inhibitory effect of the stabilizers is in the order of CT > TA > BA. The rate of degradation of AH(2) in the presence of these stabilizers in the light is about 120 times higher than that in the dark. This could be explained on the basis of the deactivation of AH(2) -excited triplet state by CT and TA and by the inhibition of AH(2) degradation through complex formation with BA. AH(2) leads to the formation of dehydroascorbic acid (A) by chemical and photooxidation in cream formulations.

  4. Specific bile acids inhibit hepatic fatty acid uptake

    PubMed Central

    Nie, Biao; Park, Hyo Min; Kazantzis, Melissa; Lin, Min; Henkin, Amy; Ng, Stephanie; Song, Sujin; Chen, Yuli; Tran, Heather; Lai, Robin; Her, Chris; Maher, Jacquelyn J.; Forman, Barry M.; Stahl, Andreas

    2012-01-01

    Bile acids are known to play important roles as detergents in the absorption of hydrophobic nutrients and as signaling molecules in the regulation of metabolism. Here we tested the novel hypothesis that naturally occurring bile acids interfere with protein-mediated hepatic long chain free fatty acid (LCFA) uptake. To this end stable cell lines expressing fatty acid transporters as well as primary hepatocytes from mouse and human livers were incubated with primary and secondary bile acids to determine their effects on LCFA uptake rates. We identified ursodeoxycholic acid (UDCA) and deoxycholic acid (DCA) as the two most potent inhibitors of the liver-specific fatty acid transport protein 5 (FATP5). Both UDCA and DCA were able to inhibit LCFA uptake by primary hepatocytes in a FATP5-dependent manner. Subsequently, mice were treated with these secondary bile acids in vivo to assess their ability to inhibit diet-induced hepatic triglyceride accumulation. Administration of DCA in vivo via injection or as part of a high-fat diet significantly inhibited hepatic fatty acid uptake and reduced liver triglycerides by more than 50%. In summary, the data demonstrate a novel role for specific bile acids, and the secondary bile acid DCA in particular, in the regulation of hepatic LCFA uptake. The results illuminate a previously unappreciated means by which specific bile acids, such as UDCA and DCA, can impact hepatic triglyceride metabolism and may lead to novel approaches to combat obesity-associated fatty liver disease. PMID:22531947

  5. Acid diffusion through polyaniline membranes

    SciTech Connect

    Su, T.M.; Huang, S.C.; Conklin, J.A.

    1995-12-01

    Polyaniline membranes in the undoped (base) and doped (acid) forms are studied for their utility as pervaporation membranes. The separation of water from mixtures of propionic acid, acetic acid and formic acid have been demonstrated from various feed compositions. Doped polyaniline displays an enhanced selectivity of water over these organic acids as compared with undoped polyaniline. For as-cast polyaniline membranes a diffusion coefficient (D) on the order of 10{sup -9} cm{sup 2}/sec has been determined for the flux of protons through the membranes using hydrochloric acid.

  6. Fatty acid-producing hosts

    DOEpatents

    Pfleger, Brian F; Lennen, Rebecca M

    2013-12-31

    Described are hosts for overproducing a fatty acid product such as a fatty acid. The hosts include an exogenous nucleic acid encoding a thioesterase and, optionally, an exogenous nucleic acid encoding an acetyl-CoA carboxylase, wherein an acyl-CoA synthetase in the hosts are functionally delected. The hosts prefereably include the nucleic acid encoding the thioesterase at an intermediate copy number. The hosts are preferably recominantly stable and growth-competent at 37.degree. C. Methods of producing a fatty acid product comprising culturing such hosts at 37.degree. C. are also described.

  7. Radioenzymatic assay for quinolinic acid

    SciTech Connect

    Foster, A.C.; Okuno, E.; Brougher, D.S.; Schwarcz, R.

    1986-10-01

    A new and rapid method for the determination of the excitotoxic tryptophan metabolite quinolinic acid is based on its enzymatic conversion to nicotinic acid mononucleotide and, in a second step utilizing (/sup 3/H)ATP, further to (/sup 3/H) deamido-NAD. Specificity of the assay is assured by using a highly purified preparation of the specific quinolinic acid-catabolizing enzyme, quinolinic acid phosphoribosyltransferase, in the initial step. The limit of sensitivity was found to be 2.5 pmol of quinolinic acid, sufficient to conveniently determine quinolinic acid levels in small volumes of human urine and blood plasma.

  8. Progress in engineering acid stress resistance of lactic acid bacteria.

    PubMed

    Wu, Chongde; Huang, Jun; Zhou, Rongqing

    2014-02-01

    Lactic acid bacteria (LAB) are widely used for the production of a variety of fermented foods, and are considered as probiotic due to their health-promoting effect. However, LAB encounter various environmental stresses both in industrial fermentation and application, among which acid stress is one of the most important survival challenges. Improving the acid stress resistance may contribute to the application and function of probiotic action to the host. Recently, the advent of genomics, functional genomics and high-throughput technologies have allowed for the understanding of acid tolerance mechanisms at a systems level, and many method to improve acid tolerance have been developed. This review describes the current progress in engineering acid stress resistance of LAB. Special emphasis is placed on engineering cellular microenvironment (engineering amino acid metabolism, introduction of exogenous biosynthetic capacity, and overproduction of stress response proteins) and maintaining cell membrane functionality. Moreover, strategies to improve acid tolerance and the related physiological mechanisms are also discussed.

  9. Effect of phenolic acids on glucose and organic acid metabolism by lactic acid bacteria from wine.

    PubMed

    Campos, Francisco M; Figueiredo, Ana R; Hogg, Tim A; Couto, José A

    2009-06-01

    The influence of phenolic (p-coumaric, caffeic, ferulic, gallic and protocatechuic) acids on glucose and organic acid metabolism by two strains of wine lactic acid bacteria (Oenococcus oeni VF and Lactobacillus hilgardii 5) was investigated. Cultures were grown in modified MRS medium supplemented with different phenolic acids. Cellular growth was monitored and metabolite concentrations were determined by HPLC-RI. Despite the strong inhibitory effect of most tested phenolic acids on the growth of O. oeni VF, the malolactic activity of this strain was not considerably affected by these compounds. While less affected in its growth, the capacity of L. hilgardii 5 to degrade malic acid was clearly diminished. Except for gallic acid, the addition of phenolic acids delayed the metabolism of glucose and citric acid in both strains tested. It was also found that the presence of hydroxycinnamic acids (p-coumaric, caffeic and ferulic) increased the yield of lactic and acetic acid production from glucose by O. oeni VF and not by L. hilgardii 5. The results show that important oenological characteristics of wine lactic acid bacteria, such as the malolactic activity and the production of volatile organic acids, may be differently affected by the presence of phenolic acids, depending on the bacterial species or strain.

  10. NAPAP (National Acid Precipitation Assessment Program) results on acid rain

    SciTech Connect

    Not Available

    1990-06-01

    The National Acid Precipitation Assessment Program (NAPAP) was mandated by Congress in 1980 to study the effects of acid rain. The results of 10 years of research on the effect of acid deposition and ozone on forests, particularly high elevation spruce and fir, southern pines, eastern hardwoods and western conifers, will be published this year.

  11. Acid Earth--The Global Threat of Acid Pollution.

    ERIC Educational Resources Information Center

    McCormick, John

    Acid pollution is a major international problem, but the debate it has elicited has often clouded the distinction between myth and facts. This publication attempts to concerning the acid pollution situation. This publication attempts to identify available facts. It is the first global review of the problem of acid pollution and the first to…

  12. Boric/sulfuric acid anodize - Alternative to chromic acid anodize

    NASA Astrophysics Data System (ADS)

    Koop, Rodney; Moji, Yukimori

    1992-04-01

    The suitability of boric acid/sulfuric acid anodizing (BSAA) solution as a more environmentally acceptable replacement of the chromic acid anodizing (CAA) solution was investigated. Results include data on the BSAA process optimization, the corrosion protection performance, and the compatibility with aircraft finishing. It is shown that the BSSA implementation as a substitude for CAA was successful.

  13. Circulating folic acid in plasma: relation to folic acid fortification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The implementation of folic acid fortification in the United States has resulted in unprecedented amounts of this synthetic form of folate in the American diet. Folic acid in circulation may be a useful measure of physiologic exposure to synthetic folic acid, and there is a potential for elevated co...

  14. College Chemistry Students' Mental Models of Acids and Acid Strength

    ERIC Educational Resources Information Center

    McClary, LaKeisha; Talanquer, Vicente

    2011-01-01

    The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research…

  15. Eucomic acid methanol monosolvate

    PubMed Central

    Li, Guo-Qiang; Li, Yao-Lan; Wang, Guo-Cai; Liang, Zhi-Hong; Jiang, Ren-Wang

    2011-01-01

    In the crystal structure of the title compound [systematic name: 2-hy­droxy-2-(4-hy­droxy­benz­yl)butane­dioic acid methanol monosolvate], C11H12O6·CH3OH, the dihedral angles between the planes of the carboxyl groups and the benzene ring are 51.23 (9) and 87.97 (9)°. Inter­molecular O—H⋯O hydrogen-bonding inter­actions involving the hy­droxy and carb­oxy­lic acid groups and the methanol solvent mol­ecule give a three-dimensional structure. PMID:22091200

  16. Autohydrolysis of phytic acid.

    PubMed

    Hull, S R; Gray, J S; Montgomery, R

    1999-09-10

    The autohydrolysis of phytic acid at 120 degrees C resulted in the formation of most of the phosphate esters of myo-inositol in varying amounts depending upon the reaction time. Eighteen of the 39 chromatographically distinct myo-inositol mono-, bis-, tris-, tetrakis-, pentakis-, and hexakisphosphates have been characterized using two different HPLC systems. These myo-inositol phosphates were partially purified by preparative anion-exchange chromatography under acidic and alkaline elution conditions. The combination of these two methods provides a two-tiered chromatographic approach to the rapid and sensitive identification of inositol phosphates in complex mixtures. Identification of the products was confirmed by 1D and 2D (1)H NMR analysis. The analytical procedure was applied to the autohydrolysis of the mixture of inositol phosphates from corn steep water.

  17. Optimize acid gas removal

    SciTech Connect

    Nicholas, D.M.; Wilkins, J.T.

    1983-09-01

    Innovative design of physical solvent plants for acid gas removal can materially reduce both installation and operating costs. A review of the design considerations for one physical solvent process (Selexol) points to numerous arrangements for potential improvement. These are evaluated for a specific case in four combinations that identify an optimum for the case in question but, more importantly, illustrate the mechanism for use for such optimization elsewhere.

  18. Perfluorooctanoic acid and environmental risks

    EPA Science Inventory

    Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acids (PFAA) family of chemicals, which consist of a carbon backbone typically four to fourteen carbons in length and a charged functional moiety.

  19. Ideas about Acids and Alkalis.

    ERIC Educational Resources Information Center

    Toplis, Rob

    1998-01-01

    Investigates students' ideas, conceptions, and misconceptions about acids and alkalis before and after a teaching sequence in a small-scale research project. Concludes that student understanding of acids and alkalis is lacking. (DDR)

  20. Pantothenic acid (Vitamin B5)

    MedlinePlus

    Pantothenic acid is a vitamin, also known as vitamin B5. It is widely found in both plants and animals ... Vitamin B5 is commercially available as D-pantothenic acid, as well as dexpanthenol and calcium pantothenate, which ...

  1. Folic Acid Questions and Answers

    MedlinePlus

    ... Controls NCBDDD Cancel Submit Search The CDC Folic Acid Note: Javascript is disabled or is not supported ... please visit this page: About CDC.gov . Folic Acid Homepage Facts Quiz Frequently Asked Questions General Information ...

  2. Omega-3 fatty acids (image)

    MedlinePlus

    Omega-3 fatty acids are a form of polyunsaturated fat that the body derives from food. Omega-3s (and omega-6s) are known as essential fatty acids (EFAs) because they are important for good health. ...

  3. Immunomodulatory spherical nucleic acids.

    PubMed

    Radovic-Moreno, Aleksandar F; Chernyak, Natalia; Mader, Christopher C; Nallagatla, Subbarao; Kang, Richard S; Hao, Liangliang; Walker, David A; Halo, Tiffany L; Merkel, Timothy J; Rische, Clayton H; Anantatmula, Sagar; Burkhart, Merideth; Mirkin, Chad A; Gryaznov, Sergei M

    2015-03-31

    Immunomodulatory nucleic acids have extraordinary promise for treating disease, yet clinical progress has been limited by a lack of tools to safely increase activity in patients. Immunomodulatory nucleic acids act by agonizing or antagonizing endosomal toll-like receptors (TLR3, TLR7/8, and TLR9), proteins involved in innate immune signaling. Immunomodulatory spherical nucleic acids (SNAs) that stimulate (immunostimulatory, IS-SNA) or regulate (immunoregulatory, IR-SNA) immunity by engaging TLRs have been designed, synthesized, and characterized. Compared with free oligonucleotides, IS-SNAs exhibit up to 80-fold increases in potency, 700-fold higher antibody titers, 400-fold higher cellular responses to a model antigen, and improved treatment of mice with lymphomas. IR-SNAs exhibit up to eightfold increases in potency and 30% greater reduction in fibrosis score in mice with nonalcoholic steatohepatitis (NASH). Given the clinical potential of SNAs due to their potency, defined chemical nature, and good tolerability, SNAs are attractive new modalities for developing immunotherapies.

  4. Immunomodulatory spherical nucleic acids

    PubMed Central

    Radovic-Moreno, Aleksandar F.; Chernyak, Natalia; Mader, Christopher C.; Nallagatla, Subbarao; Kang, Richard S.; Hao, Liangliang; Walker, David A.; Halo, Tiffany L.; Merkel, Timothy J.; Rische, Clayton H.; Anantatmula, Sagar; Burkhart, Merideth; Mirkin, Chad A.; Gryaznov, Sergei M.

    2015-01-01

    Immunomodulatory nucleic acids have extraordinary promise for treating disease, yet clinical progress has been limited by a lack of tools to safely increase activity in patients. Immunomodulatory nucleic acids act by agonizing or antagonizing endosomal toll-like receptors (TLR3, TLR7/8, and TLR9), proteins involved in innate immune signaling. Immunomodulatory spherical nucleic acids (SNAs) that stimulate (immunostimulatory, IS-SNA) or regulate (immunoregulatory, IR-SNA) immunity by engaging TLRs have been designed, synthesized, and characterized. Compared with free oligonucleotides, IS-SNAs exhibit up to 80-fold increases in potency, 700-fold higher antibody titers, 400-fold higher cellular responses to a model antigen, and improved treatment of mice with lymphomas. IR-SNAs exhibit up to eightfold increases in potency and 30% greater reduction in fibrosis score in mice with nonalcoholic steatohepatitis (NASH). Given the clinical potential of SNAs due to their potency, defined chemical nature, and good tolerability, SNAs are attractive new modalities for developing immunotherapies. PMID:25775582

  5. Microbial naphthenic Acid degradation.

    PubMed

    Whitby, Corinne

    2010-01-01

    Naphthenic acids (NAs) are an important group of trace organic pollutants predominantly comprising saturated aliphatic and alicyclic carboxylic acids. NAs are ubiquitous; occurring naturally in hydrocarbon deposits (petroleum, oil sands, bitumen, and crude oils) and also have widespread industrial uses. Consequently, NAs can enter the environment from both natural and anthropogenic processes. NAs are highly toxic, recalcitrant compounds that persist in the environment for many years, and it is important to develop efficient bioremediation strategies to decrease both their abundance and toxicity in the environment. However, the diversity of microbial communities involved in NA-degradation, and the mechanisms by which NAs are biodegraded, are poorly understood. This lack of knowledge is mainly due to the difficulties in identifying and purifying individual carboxylic acid compounds from complex NA mixtures found in the environment, for microbial biodegradation studies. This paper will present an overview of NAs, their origin and fate in the environment, and their toxicity to the biota. The review describes the microbial degradation of both naturally occurring and chemically synthesized NAs. Proposed pathways for aerobic NA biodegradation, factors affecting NA biodegradation rates, and possible bioremediation strategies are also discussed.

  6. Noncanonical FK506-binding Protein BDBT Binds DBT to Enhance its Circadian Function and Forms Foci at Night

    PubMed Central

    Fan, Jin-Yuan; Agyekum, Boadi; Venkatesan, Anandakrishnan; Hall, David R.; Keightley, Andrew; Bjes, Edward S.; Bouyain, Samuel; Price, Jeffrey L.

    2013-01-01

    SUMMARY The kinase DOUBLETIME is a master regulator of the Drosophila circadian clock, yet the mechanisms regulating its activity remain unclear. A proteomic analysis of DOUBLETIME interactors led to the identification of an unstudied protein designated CG17282. RNAi-mediated knock-down of CG17282 produced behavioral arrhythmicity and long periods, high levels of hypophosphorylated nuclear PERIOD and phosphorylated DOUBLETIME. Overexpression of DOUBLETIME in flies suppresses these phenotypes and overexpression of CG17282 in S2 cells enhances DOUBLETIME-dependent PERIOD degradation, indicating that CG17282 stimulates DOUBLETIME’s circadian function. In photoreceptors, CG17282 accumulates rhythmically in PERIOD- and DOUBLETIME-dependent cytosolic foci. Finally, structural analyses demonstrated CG17282 is a noncanonical FK506-binding protein with an inactive peptide prolyl-isomerase domain that binds DOUBLETIME and tetratricopeptide repeats that may promote assembly of larger protein complexes. We have named CG17282 Bride of Doubletime and established it as a mediator of DOUBLETIME’s effects on PERIOD, most likely in cytosolic foci that regulate PERIOD nuclear accumulation. PMID:24210908

  7. Amino acids in carbonaceous chondrites

    NASA Technical Reports Server (NTRS)

    Lawless, J. G.; Peterson, E.

    1975-01-01

    Studies with the combined gas chromatograph-mass spectrometer were conducted to characterize further the amino acids found in extracts of the Murchison meteorite. With the exception of beta-aminoisobutyric acid, all of the amino acids which were found in previous studies of the Murchison meteorite and the Murray meteorite have been identified. The results obtained lend further support to the hypothesis that amino acids are present in the Murchison meteorite as the result of an extraterrestrial abiotic synthesis.

  8. Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

    PubMed

    Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

    2002-12-06

    Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.

  9. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C. Judson; Poole, Loree J.

    1995-01-01

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine.

  10. An Umbrella for Acid Rain.

    ERIC Educational Resources Information Center

    Randal, Judith

    1979-01-01

    The Environmental Protection Agency has awarded several grants to study effects of and possible solutions to the problem of "acid rain"; pollution from atmospheric nitric and sulfuric acids. The research program is administered through North Carolina State University at Raleigh and will focus on biological effects of acid rain. (JMF)

  11. Carboxylic acid sorption regeneration process

    DOEpatents

    King, C.J.; Poole, L.J.

    1995-05-02

    Carboxylic acids are sorbed from aqueous feedstocks into an organic liquid phase or onto a solid adsorbent. The acids are freed from the sorbent phase by treating it with aqueous alkylamine thus forming an alkylammonium carboxylate which is dewatered and decomposed to the desired carboxylic acid and the alkylamine. 10 figs.

  12. Scientists Puzzle Over Acid Rain

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1975

    1975-01-01

    Reports on a growing concern over increased acidity in atmospheric percipitation. Explores possible causes of the increased acidity, identifies chemical components of precipitation in various parts of the world, and presents environmental changes that might be attributed to the acidity. (GS)

  13. [Total synthesis of nordihydroguaiaretic acid].

    PubMed

    Wu, A X; Zhao, Y R; Chen, N; Pan, X F

    1997-04-01

    beta-Keto ester(5) was obtained from vanilin through etherification, oxidation and condensation with acetoacetic ester, (5) on oxidative coupling reaction by NaOEt/I2 produced dimer (6) in high yield. Acid catalyzed cyclodehydration of (6) gave the furan derivative(7), and by a series of selective hydrogenation nordihydroguaiaretic acid, furoguaiacin dimethyl ether and dihydroguaiaretic acid dimethyl ether were synthesized.

  14. Pantothenic acid biosynthesis in zymomonas

    SciTech Connect

    Tao, Luan; Tomb, Jean-Francois; Viitanen, Paul V.

    2014-07-01

    Zymomonas is unable to synthesize pantothenic acid and requires this essential vitamin in growth medium. Zymomonas strains transformed with an operon for expression of 2-dehydropantoate reductase and aspartate 1-decarboxylase were able to grow in medium lacking pantothenic acid. These strains may be used for ethanol production without pantothenic acid supplementation in seed culture and fermentation media.

  15. Microbial degradation of poly(amino acid)s.

    PubMed

    Obst, Martin; Steinbüchel, Alexander

    2004-01-01

    Natural poly(amino acid)s are a group of poly(ionic) molecules (ionomers) with various biological functions and putative technical applications and play, therefore, an important role both in nature and in human life. Because of their biocompatibility and their synthesis from renewable resources, poly(amino acid)s may be employed for many different purposes covering a broad spectrum of medical, pharmaceutical, and personal care applications as well as the domains of agriculture and of environmental applications. Biodegradability is one important advantage of naturally occurring poly(amino acid)s over many synthetic polymers. The intention of this review is to give an overview about the enzyme systems catalyzing the initial steps in poly(amino acid) degradation. The focus is on the naturally occurring poly(amino acid)s cyanophycin, poly(epsilon-L-lysine) and poly(gamma-glutamic acid); but biodegradation of structurally related synthetic polyamides such as poly(aspartic acid) and nylons, which are known from various technical applications, is also included.

  16. Photoexcited triplet states of UV-B absorbers: ethylhexyl triazone and diethylhexylbutamido triazone.

    PubMed

    Tsuchiya, Takumi; Kikuchi, Azusa; Oguchi-Fujiyama, Nozomi; Miyazawa, Kazuyuki; Yagi, Mikio

    2015-04-01

    The excited states of UV-B absorbers, ethylhexyl triazone (EHT) and diethylhexylbutamido triazone (DBT), have been studied through measurements of UV absorption, fluorescence, phosphorescence, triplet-triplet absorption and electron paramagnetic resonance spectra in ethanol. The energy levels of the lowest excited singlet (S1) and triplet (T1) states and quantum yields of fluorescence and phosphorescence of EHT and DBT were determined. In ethanol at 77 K, the deactivation process of EHT and DBT is predominantly fluorescence, however, a significant portion of the S1 molecules undergoes intersystem crossing to the T1 state. The observed phosphorescence spectra, T1 lifetimes and zero-field splitting parameters suggest that the T1 state of EHT can be assigned to a locally excited (3)ππ* state within p-(N-methylamino)benzoic acid, while the T1 state of DBT can be assigned to a locally excited (3)ππ* state within p-(N-methylamino)benzoic acid or p-amino-N-methylbenzamide. The quantum yields of singlet oxygen generation by EHT and DBT were determined by time-resolved near-IR phosphorescence measurements in ethanol at room temperature. EHT and DBT did not exhibit significantly antioxidative properties by quenching singlet oxygen, in contrast to the study by Lhiaubet-Vallet et al.

  17. A novel integration system of magnetically immobilized cells and a pair of graphite plate-stainless iron mesh electrodes for the bioremediation of coking wastewater.

    PubMed

    Jiang, Bei; Tan, Liang; Ning, Shuxiang; Shi, Shengnan

    2016-09-01

    Magnetically immobilized cells of Comamonas sp. JB coupling with electrode reaction was developed to enhance the treatment efficiency of coking wastewater containing phenol, carbazole (CA), dibenzofuran (DBF), and dibenzothiophene (DBT). The pair of graphite plate-stainless iron mesh electrodes was chosen as the most suitable electrodes. Magnetically immobilized cells coupling with graphite plate-stainless iron mesh electrodes (coupling system) exhibited high degradation activity for all the compounds, which were significantly higher than the sum by single magnetically immobilized cells and electrode reaction at the optimal voltage. Recycling experiments demonstrated that the degradation activity of coupling system increased gradually during eight recycles, indicating that there was a coupling effect between the biodegradation and electrode reaction. Phenol hydroxylase and qPCR assays confirmed that appropriate electrical stimulation could improve phenol hydroxylase activity and promote cells growth. Toxicity assessment suggested the treatment of the coking wastewater by coupling system led to less toxicity than untreated wastewater.

  18. The efficient synthesis of a molybdenum carbide catalyst via H2-thermal treatment of a Mo(VI)-hexamethylenetetramine complex.

    PubMed

    Wang, Zhi-Qiang; Zhang, Zhong-Biao; Zhang, Ming-Hui

    2011-02-07

    An efficient method for preparation of Mo(2)C catalyst is described, where Mo(2)C is obtained by the heat treatment of a single solid precursor containing (NH(4))(6)Mo(7)O(24) and hexamethylenetetramine (HMT) at 923 K in H(2) flow without conventional prolonged carbonization. The catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), BET surface area measurement, and transmission electron microscopy (TEM). Furthermore, these catalysts are evaluated in the dibenzothiophene (DBT) hydrodesulfurization (HDS) reaction, and proved to be superior to those prepared by a temperature-programmed reduction (TPRe) method. The better catalytic performance is ascribed to higher dispersion of Mo(2)C on the support and a lower surface polymeric carbon content. This hydrogen thermal treatment (HTT) method provided a new strategy for the preparation of a highly active molybdenum carbide catalyst.

  19. Composition for nucleic acid sequencing

    DOEpatents

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2008-08-26

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  20. Evolution of rosmarinic acid biosynthesis.

    PubMed

    Petersen, Maike; Abdullah, Yana; Benner, Johannes; Eberle, David; Gehlen, Katja; Hücherig, Stephanie; Janiak, Verena; Kim, Kyung Hee; Sander, Marion; Weitzel, Corinna; Wolters, Stefan

    2009-01-01

    Rosmarinic acid and chlorogenic acid are caffeic acid esters widely found in the plant kingdom and presumably accumulated as defense compounds. In a survey, more than 240 plant species have been screened for the presence of rosmarinic and chlorogenic acids. Several rosmarinic acid-containing species have been detected. The rosmarinic acid accumulation in species of the Marantaceae has not been known before. Rosmarinic acid is found in hornworts, in the fern family Blechnaceae and in species of several orders of mono- and dicotyledonous angiosperms. The biosyntheses of caffeoylshikimate, chlorogenic acid and rosmarinic acid use 4-coumaroyl-CoA from the general phenylpropanoid pathway as hydroxycinnamoyl donor. The hydroxycinnamoyl acceptor substrate comes from the shikimate pathway: shikimic acid, quinic acid and hydroxyphenyllactic acid derived from l-tyrosine. Similar steps are involved in the biosyntheses of rosmarinic, chlorogenic and caffeoylshikimic acids: the transfer of the 4-coumaroyl moiety to an acceptor molecule by a hydroxycinnamoyltransferase from the BAHD acyltransferase family and the meta-hydroxylation of the 4-coumaroyl moiety in the ester by a cytochrome P450 monooxygenase from the CYP98A family. The hydroxycinnamoyltransferases as well as the meta-hydroxylases show high sequence similarities and thus seem to be closely related. The hydroxycinnamoyltransferase and CYP98A14 from Coleus blumei (Lamiaceae) are nevertheless specific for substrates involved in RA biosynthesis showing an evolutionary diversification in phenolic ester metabolism. Our current view is that only a few enzymes had to be "invented" for rosmarinic acid biosynthesis probably on the basis of genes needed for the formation of chlorogenic and caffeoylshikimic acid while further biosynthetic steps might have been recruited from phenylpropanoid metabolism, tocopherol/plastoquinone biosynthesis and photorespiration.

  1. The politics of acid rain

    SciTech Connect

    Wilcher, M.E. )

    1989-01-01

    This work examines and compares the acid rain policies through the different political systems of Canada, Great Britain and the United States. Because the flow of acid rain can transcend national boundaries, acid rain has become a crucial international problem. According to the author, because of differences in governmental institutions and structure, the extent of governmental intervention in the industrial economy, the degree of reliance on coal for power generation, and the extent of acid rain damage, national responses to the acid rain problem have varied.

  2. [Stewart's acid-base approach].

    PubMed

    Funk, Georg-Christian

    2007-01-01

    In addition to paCO(2), Stewart's acid base model takes into account the influence of albumin, inorganic phosphate, electrolytes and lactate on acid-base equilibrium. It allows a comprehensive and quantitative analysis of acid-base disorders. Particularly simultaneous and mixed metabolic acid-base disorders, which are common in critically ill patients, can be assessed. Stewart's approach is therefore a valuable tool in addition to the customary acid-base approach based on bicarbonate or base excess. However, some chemical aspects of Stewart's approach remain controversial.

  3. Tested Demonstrations: Color Oscillations in the Formic Acid-Nitric Acid-Sulfuric Acid System.

    ERIC Educational Resources Information Center

    Raw, C. J. G.; And Others

    1983-01-01

    Presented are procedures for demonstrating the production of color oscillations when nitric acid is added to a formic acid/concentrated sulfuric acid mixture. Because of safety considerations, "Super-8" home movie of the color changes was found to be satisfactory for demonstration purposes. (JN)

  4. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-11-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids and quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (< 0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanic emissions.

  5. Amino acids in Arctic aerosols

    NASA Astrophysics Data System (ADS)

    Scalabrin, E.; Zangrando, R.; Barbaro, E.; Kehrwald, N. M.; Gabrieli, J.; Barbante, C.; Gambaro, A.

    2012-07-01

    Amino acids are significant components of atmospheric aerosols, affecting organic nitrogen input to marine ecosystems, atmospheric radiation balance, and the global water cycle. The wide range of amino acid reactivities suggest that amino acids may serve as markers of atmospheric transport and deposition of particles. Despite this potential, few measurements have been conducted in remote areas to assess amino acid concentrations and potential sources. Polar regions offer a unique opportunity to investigate atmospheric processes and to conduct source apportionment studies of such compounds. In order to better understand the importance of amino acid compounds in the global atmosphere, we determined free amino acids (FAAs) in seventeen size-segregated aerosol samples collected in a polar station in the Svalbard Islands from 19 April until 14 September 2010. We used an HPLC coupled with a tandem mass spectrometer (ESI-MS/MS) to analyze 20 amino acids to quantify compounds at fmol m-3 levels. Mean total FAA concentration was 1070 fmol m-3 where serine and glycine were the most abundant compounds in almost all samples and accounted for 45-60% of the total amino acid relative abundance. The other eighteen compounds had average concentrations between 0.3 and 98 fmol m-3. The higher amino acid concentrations were present in the ultrafine aerosol fraction (<0.49 μm) and accounted for the majority of the total amino acid content. Local marine sources dominate the boreal summer amino acid concentrations, with the exception of the regional input from Icelandic volcanics.

  6. Twinning of dodecanedicarboxylic acid

    NASA Technical Reports Server (NTRS)

    Sen, R.; Wilcox, W. R.

    1986-01-01

    Twinning of 1,10-dodecanedicarboxyl acid (DDA) was observed in 0.1 mm thick films with a polarizing microscope. Twins originated from polycrystalline regions which tended to nucleate on twin faces, and terminated by intersection gone another. Twinning increased dramatically with addition of organic compounds with a similar molecular size and shape. Increasing the freezing rate, increasing the temperature gradient, and addition of silica particles increased twinning. It is proposed that twins nucleate with polycrystals and sometimes anneal out before they become observable. The impurities may enhance twinning either by lowering the twin energy or by adsorbing on growing faces.

  7. Synthesis of amino acids

    DOEpatents

    Davis, J.W. Jr.

    1979-09-21

    A method is described for synthesizing amino acids preceding through novel intermediates of the formulas: R/sub 1/R/sub 2/C(OSOC1)CN, R/sub 1/R/sub 2/C(C1)CN and (R/sub 1/R/sub 2/C(CN)O)/sub 2/SO wherein R/sub 1/ and R/sub 2/ are each selected from hydrogen and monovalent hydrocarbon radicals of 1 to 10 carbon atoms. The use of these intermediates allows the synthesis steps to be exothermic and results in an overall synthesis method which is faster than the synthesis methods of the prior art.

  8. New highly toxic bile acids derived from deoxycholic acid, chenodeoxycholic acid and lithocholic acid.

    PubMed

    Májer, Ferenc; Sharma, Ruchika; Mullins, Claire; Keogh, Luke; Phipps, Sinead; Duggan, Shane; Kelleher, Dermot; Keely, Stephen; Long, Aideen; Radics, Gábor; Wang, Jun; Gilmer, John F

    2014-01-01

    We have prepared a new panel of 23 BA derivatives of DCA, chenodeoxycholic acid (CDCA) and lithocholic acid (LCA) in order to study the effect of dual substitution with 3-azido and 24-amidation, features individually associated with cytotoxicity in our previous work. The effect of the compounds on cell viability of HT-1080 and Caco-2 was studied using the 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Compounds with high potency towards reduction of cell viability were further studied using flow cytometry in order to understand the mechanism of cell death. Several compounds were identified with low micromolar IC₅₀ values for reducing cell viability in the Caco-2 and HT1080 cell lines, making them among the most potent BA apoptotic agents reported to date. There was no evidence of relationship between overall hydrophobicity and cytotoxicity supporting the idea that cell death induction by BAs may be structure-specific. Compounds derived from DCA caused cell death through apoptosis. There was some evidence of selectivity between the two cell lines studied which may be due to differing expression of CD95/FAS. The more toxic compounds increased ROS production in Caco-2 cells, and co-incubation with the antioxidant N-acetyl cysteine blunted pro-apoptotic effects. The properties these compounds suggest that there may be specific mechanism(s) mediating BA induced cell death. Compound 8 could be useful for investigating this phenomenon.

  9. Cryoprotection from lipoteichoic acid

    NASA Astrophysics Data System (ADS)

    Rice, Charles V.; Middaugh, Amy; Wickham, Jason R.; Friedline, Anthony; Thomas, Kieth J.; Johnson, Karen; Zachariah, Malcolm; Garimella, Ravindranth

    2012-10-01

    Numerous chemical additives lower the freezing point of water, but life at sub-zero temperatures is sustained by a limited number of biological cryoprotectants. Antifreeze proteins in fish, plants, and insects provide protection to a few degrees below freezing. Microbes have been found to survive at even lower temperatures, and with a few exceptions, antifreeze proteins are missing. Survival has been attributed to external factors, such as the high salt concentration of brine veins and adhesion to particulates or ice crystal defects. We have discovered an endogenous cryoprotectant in the cell wall of bacteria, lipoteichoic acid biopolymers. Adding 1% LTA to bacteria cultures immediately prior to freezing provides 50% survival rate, similar to the results obtained with 1% glycerol. In the absence of an additive, bacterial survival is negligible as measured with the resazurin cell viability assay. The mode of action for LTA cryoprotection is unknown. With a molecular weight of 3-5 kDa, it is unlikely to enter the cell cytoplasm. Our observations suggest that teichoic acids could provide a shell of liquid water around biofilms and planktonic bacteria, removing the need for brine veins to prevent bacterial freezing.

  10. Nucleic Acid Detection Methods

    DOEpatents

    Smith, Cassandra L.; Yaar, Ron; Szafranski, Przemyslaw; Cantor, Charles R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3'-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated.

  11. Nucleic acid detection methods

    DOEpatents

    Smith, C.L.; Yaar, R.; Szafranski, P.; Cantor, C.R.

    1998-05-19

    The invention relates to methods for rapidly determining the sequence and/or length a target sequence. The target sequence may be a series of known or unknown repeat sequences which are hybridized to an array of probes. The hybridized array is digested with a single-strand nuclease and free 3{prime}-hydroxyl groups extended with a nucleic acid polymerase. Nuclease cleaved heteroduplexes can be easily distinguish from nuclease uncleaved heteroduplexes by differential labeling. Probes and target can be differentially labeled with detectable labels. Matched target can be detected by cleaving resulting loops from the hybridized target and creating free 3-hydroxyl groups. These groups are recognized and extended by polymerases added into the reaction system which also adds or releases one label into solution. Analysis of the resulting products using either solid phase or solution. These methods can be used to detect characteristic nucleic acid sequences, to determine target sequence and to screen for genetic defects and disorders. Assays can be conducted on solid surfaces allowing for multiple reactions to be conducted in parallel and, if desired, automated. 18 figs.

  12. Ribonucleic acid purification.

    PubMed

    Martins, R; Queiroz, J A; Sousa, F

    2014-08-15

    Research on RNA has led to many important biological discoveries and improvement of therapeutic technologies. From basic to applied research, many procedures employ pure and intact RNA molecules; however their isolation and purification are critical steps because of the easy degradability of RNA, which can impair chemical stability and biological functionality. The current techniques to isolate and purify RNA molecules still have several limitations and the requirement for new methods able to improve RNA quality to meet regulatory demands is growing. In fact, as basic research improves the understanding of biological roles of RNAs, the biopharmaceutical industry starts to focus on them as a biotherapeutic tools. Chromatographic bioseparation is a high selective unit operation and is the major option in the purification of biological compounds, requiring high purity degree. In addition, its application in biopharmaceutical manufacturing is well established. This paper discusses the importance and the progress of RNA isolation and purification, considering RNA applicability both in research and clinical fields. In particular and in view of the high specificity, affinity chromatography has been recently applied to RNA purification processes. Accordingly, recent chromatographic investigations based on biorecognition phenomena occurring between RNA and amino acids are focused. Histidine and arginine have been used as amino acid ligands, and their ability to isolate different RNA species demonstrated a multipurpose applicability in molecular biology analysis and RNA therapeutics preparation, highlighting the potential contribution of these methods to overcome the challenges of RNA purification.

  13. Growth of nitric acid hydrates on thin sulfuric acid films

    NASA Technical Reports Server (NTRS)

    Iraci, Laura T.; Middlebrook, Ann M.; Wilson, Margaret A.; Tolbert, Margaret A.

    1994-01-01

    Type I polar stratospheric clouds (PSCs) are thought to nucleate and grow on stratospheric sulfate aerosols (SSAs). To model this system, thin sulfuric acid films were exposed to water and nitric acid vapors (1-3 x 10(exp -4) Torr H2O and 1-2.5 x 10(exp -6) Torr HNO3) and subjected to cooling and heating cycles. Fourier Transform Infrared (FTIR) spectroscopy was used to probe the phase of the sulfuric acid and to identify the HNO3/H2O films that condensed. Nitric acid trihydrate (NAT) was observed to grow on crystalline sulfuric acid tetrahydrate (SAT) films. NAT also condensed in/on supercooled H2SO4 films without causing crystallization of the sulfuric acid. This growth is consistent with NAT nucleation from ternary solutions as the first step in PSC formation.

  14. CELL PENETRATION BY ACIDS : VI. THE CHLOROACETIC ACIDS.

    PubMed

    Crozier, W J

    1922-09-20

    Measurements of the penetration of tissue from Chromodoris zebra are believed to show that a determining factor in penetration involves the establishment of a critical pH (near 3.5) in relation to superficial cell proteins. The rapidity with which this state is produced depends upon acid strength, and upon some property of the acid influencing the speed of absorption; hence it is necessary to compare acids within groups of chemical relationship. The actual speed of penetration observed with any acid is dependent upon two influences: preliminary chemical combination with the outer protoplasm, followed by diffusion. The variation of the temperature coefficient of penetration velocity with the concentration of acid, and the effect of size (age) of individual providing the tissue sample agree in demonstrating the significant part played by diffusion. In comparing different acids, however, their mode of chemical union with the protoplasm determines the general order of penetrating ability.

  15. Bile acids: regulation of synthesis.

    PubMed

    Chiang, John Y L

    2009-10-01

    Bile acids are physiological detergents that generate bile flow and facilitate intestinal absorption and transport of lipids, nutrients, and vitamins. Bile acids also are signaling molecules and inflammatory agents that rapidly activate nuclear receptors and cell signaling pathways that regulate lipid, glucose, and energy metabolism. The enterohepatic circulation of bile acids exerts important physiological functions not only in feedback inhibition of bile acid synthesis but also in control of whole-body lipid homeostasis. In the liver, bile acids activate a nuclear receptor, farnesoid X receptor (FXR), that induces an atypical nuclear receptor small heterodimer partner, which subsequently inhibits nuclear receptors, liver-related homolog-1, and hepatocyte nuclear factor 4alpha and results in inhibiting transcription of the critical regulatory gene in bile acid synthesis, cholesterol 7alpha-hydroxylase (CYP7A1). In the intestine, FXR induces an intestinal hormone, fibroblast growth factor 15 (FGF15; or FGF19 in human), which activates hepatic FGF receptor 4 (FGFR4) signaling to inhibit bile acid synthesis. However, the mechanism by which FXR/FGF19/FGFR4 signaling inhibits CYP7A1 remains unknown. Bile acids are able to induce FGF19 in human hepatocytes, and the FGF19 autocrine pathway may exist in the human livers. Bile acids and bile acid receptors are therapeutic targets for development of drugs for treatment of cholestatic liver diseases, fatty liver diseases, diabetes, obesity, and metabolic syndrome.

  16. Therapeutic targeting of bile acids

    PubMed Central

    Gores, Gregory J.

    2015-01-01

    The first objectives of this article are to review the structure, chemistry, and physiology of bile acids and the types of bile acid malabsorption observed in clinical practice. The second major theme addresses the classical or known properties of bile acids, such as the role of bile acid sequestration in the treatment of hyperlipidemia; the use of ursodeoxycholic acid in therapeutics, from traditional oriental medicine to being, until recently, the drug of choice in cholestatic liver diseases; and the potential for normalizing diverse bowel dysfunctions in irritable bowel syndrome, either by sequestering intraluminal bile acids for diarrhea or by delivering more bile acids to the colon to relieve constipation. The final objective addresses novel concepts and therapeutic opportunities such as the interaction of bile acids and the microbiome to control colonic infections, as in Clostridium difficile-associated colitis, and bile acid targeting of the farnesoid X receptor and G protein-coupled bile acid receptor 1 with consequent effects on energy expenditure, fat metabolism, and glycemic control. PMID:26138466

  17. [Analysis of citric acid and citrates. Citric acid and urolithiasis].

    PubMed

    Leskovar, P

    1979-08-01

    In the first part the physico-chemical, analytic chemical and physiologic biochemical properties of the citric acid are discussed. In the second part the author enters the role of the citric acid in the formation of uric calculi. In the third part is reported on the individual methods of the determination of citric acid and the method practised in the author's laboratory is described.

  18. Rotational study of the bimolecule acetic acid-fluoroacetic acid

    NASA Astrophysics Data System (ADS)

    Feng, Gang; Gou, Qian; Evangelisti, Luca; Caminati, Walther

    2017-01-01

    The rotational spectrum of the acetic acid-fluoroacetic acid bimolecule was measured by using a pulsed jet Fourier transform microwave spectrometer. One conformer, in which fluoroacetic acid is in trans form, has been observed. The rotational transitions are split into two component lines, due to the internal rotation of the methyl group of acetic acid. From these splittings, the corresponding V3 barrier has been determined. The dissociation energy of this complex has been estimated to 66 kJ/mol. An increase of the distance between the two monomers upon the OH → OD substitution (Ubbelohde effect) has been observed.

  19. Esterification by the Plasma Acidic Water: Novel Application of Plasma Acid

    NASA Astrophysics Data System (ADS)

    Gu, Ling

    2014-03-01

    This work explores the possibility of plasma acid as acid catalyst in organic reactions. Plasma acidic water was prepared by dielectric barrier discharge and used to catalyze esterification of n-heptanioc acid with ethanol. It is found that the plasma acidic water has a stable and better performance than sulfuric acid, meaning that it is an excellent acid catalyst. The plasma acidic water would be a promising alternative for classic mineral acid as a more environment friendly acid.

  20. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  1. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  2. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  3. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  4. 49 CFR 173.158 - Nitric acid.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Nitric acid. 173.158 Section 173.158... Nitric acid. (a) Nitric acid exceeding 40 percent concentration may not be packaged with any other material. (b) Nitric acid in any concentration which does not contain sulfuric acid or hydrochloric acid...

  5. [Women's knowledge of folic acid].

    PubMed

    Salgues, Mathilde; Damase-Michel, Christine; Montastruc, Jean-Louis; Lacroix, Isabelle

    2016-10-27

    Many trials have shown that folic acid supplementation before and during pregnancy reduces the risk of neural tube defects in general population. We investigated the knowledge of folic acid in women of child-bearing age. Women of child-bearing age were interviewed by 20 pharmacists living in Haute-Garonne between January and February 2014. One hundred ninety-six women were included in the present study. Out of them, 36% of women never heard of folic acid and 82% were not aware of its benefits. Knowledge was higher in older women, women in a couple and women with higher educational level (P<10(-2)). This study underlines that women are not enough aware of benefits of folic acid during pregnancy. Moreover, previous studies have shown that French women have low use of folic acid during peri-conceptional period. Information of general population will be required for a better prevention of folic acid-preventable NTDs.

  6. Flecainide acetate acetic acid solvates.

    PubMed

    Veldre, Kaspars; Actiņs, Andris; Eglite, Zane

    2011-02-01

    Flecainide acetate forms acetic acid solvates with 0.5 and 2 acetic acid molecules. Powder X-ray diffraction, differential thermal analysis/thermogravimetric, infrared, and potentiometric titration were used to determine the composition of solvates. Flecainide acetate hemisolvate with acetic acid decomposes to form a new crystalline form of flecainide acetate. This form is less stable than the already known polymorphic form at all temperatures, and it is formed due to kinetic reasons. Both flecainide acetate nonsolvated and flecainide acetate hemisolvate forms crystallize in monoclinic crystals, but flecainide triacetate forms triclinic crystals. Solvate formation was not observed when flecainide base was treated with formic acid, propanoic acid, and butanoic acid. Only nonsolvated flecainide salts were obtained in these experiments.

  7. A Simpler Nucleic Acid

    NASA Technical Reports Server (NTRS)

    Orgel, Leslie

    2000-01-01

    It has been supposed that for a nucleic acid analog to pair with RNA it must, like RNA, have a backbone with at least a sixatom repeat; a shorter backbone presumably would not stretch far enough to bind RNA properly. The Eschenmoser group has shown, however, that this first impression is incorrect.As they report in their new paper, Eschenmoser and co-workers ( I ) have now synthesized a substantial number of these polymers, which are called (L)-a-threofuranosyl oligonucleotides or TNAs. They are composed of bases linked to a threose sugar-phosphate backbone, with phosphodiester bonds connecting the nucleotides. The investigators discovered that pairs of complementary TNAs do indeed form stable Watson-Crick double helices and, perhaps more importantly, that TNAs form stable double helices with complementary RNAs and DNAs.

  8. Acid mine drainage

    USGS Publications Warehouse

    Bigham, Jerry M.; Cravotta, Charles A.

    2016-01-01

    Acid mine drainage (AMD) consists of metal-laden solutions produced by the oxidative dissolution of iron sulfide minerals exposed to air, moisture, and acidophilic microbes during the mining of coal and metal deposits. The pH of AMD is usually in the range of 2–6, but mine-impacted waters at circumneutral pH (5–8) are also common. Mine drainage usually contains elevated concentrations of sulfate, iron, aluminum, and other potentially toxic metals leached from rock that hydrolyze and coprecipitate to form rust-colored encrustations or sediments. When AMD is discharged into surface waters or groundwaters, degradation of water quality, injury to aquatic life, and corrosion or encrustation of engineered structures can occur for substantial distances. Prevention and remediation strategies should consider the biogeochemical complexity of the system, the longevity of AMD pollution, the predictive power of geochemical modeling, and the full range of available field technologies for problem mitigation.

  9. Production of polymalic acid and malic acid by Aureobasidium pullulans fermentation and acid hydrolysis.

    PubMed

    Zou, Xiang; Zhou, Yipin; Yang, Shang-Tian

    2013-08-01

    Malic acid is a dicarboxylic acid widely used in the food industry and also a potential C4 platform chemical that can be produced from biomass. However, microbial fermentation for direct malic acid production is limited by low product yield, titer, and productivity due to end-product inhibition. In this work, a novel process for malic acid production from polymalic acid (PMA) fermentation followed by acid hydrolysis was developed. First, a PMA-producing Aureobasidium pullulans strain ZX-10 was screened and isolated. This microbe produced PMA as the major fermentation product at a high-titer equivalent to 87.6 g/L of malic acid and high-productivity of 0.61 g/L h in free-cell fermentation in a stirred-tank bioreactor. Fed-batch fermentations with cells immobilized in a fibrous-bed bioreactor (FBB) achieved the highest product titer of 144.2 g/L and productivity of 0.74 g/L h. The fermentation produced PMA was purified by adsorption with IRA-900 anion-exchange resins, achieving a ∼100% purity and a high recovery rate of 84%. Pure malic acid was then produced from PMA by hydrolysis with 2 M sulfuric acid at 85°C, which followed the first-order reaction kinetics. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application.

  10. Fabrication of photocatalytic composite of multi-walled carbon nanotubes/TiO{sub 2} and its application for desulfurization of diesel

    SciTech Connect

    Vu, Thu Ha Thi; Nguyen, Thu Trang Thi; Nguyen, Phuong Hoa Thi; Do, Manh Hung; Au, Hang Thi; Nguyen, Thanh Binh; Nguyen, Dinh Lam; Park, Jun Seo

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer MWNTs and TiO{sub 2} were mixed well, forming uniform microstructure in MWNTs/TiO{sub 2} composites. Black-Right-Pointing-Pointer The combination of MWNTs and TiO{sub 2} contribute to improving photocatalytic activity of TiO{sub 2}. Black-Right-Pointing-Pointer MWNTs/TiO{sub 2} composite is an effective photo-catalyst for the removal of sulfur from commercial diesel. -- Abstract: Composite of multi-walled carbon nanotubes (MWNTs) and titanium (IV) oxide (TiO{sub 2}) were prepared by a heterogeneous gelation method. The activities of the MWNTs/TiO{sub 2} composites were evaluated by photocatalytic oxidative desulfurization using dibenzothiophene (DBT), 4,6-dimethyl dibenzothiophene (4,6-DMDBT), n-tetradecane, and commercial diesel under irradiation using a high-pressure Hg lamp. The microstructures of MWNTs/TiO{sub 2} composites were characterized by N{sub 2} adsorption, scanning electron microscopy, transmission electron microscope, and X-ray diffraction. It was found that more than 98% of sulfur compounds in commercial diesel were oxidized and removed by the use of the MWNTs/TiO{sub 2} composite as a photocatalyst.

  11. Evaluating the Bone Tissue Regeneration Capability of the Chinese Herbal Decoction Danggui Buxue Tang from a Molecular Biology Perspective

    PubMed Central

    Wang, Wen-Ling; Sheu, Shi-Yuan; Kao, Shung-Te; Fu, Yuan-Tsung; Kuo, Tzong-Fu; Yao, Chun-Hsu

    2014-01-01

    Large bone defects are a considerable challenge to reconstructive surgeons. Numerous traditional Chinese herbal medicines have been used to repair and regenerate bone tissue. This study investigated the bone regeneration potential of Danggui Buxue Tang (DBT), a Chinese herbal decoction prepared from Radix Astragali (RA) and Radix Angelicae Sinensis (RAS), from a molecular biology perspective. The optimal ratio of RA and RAS used in DBT for osteoblast culture was obtained by colorimetric and alkaline phosphatase (ALP) activity assays. Moreover, the optimal concentration of DBT for bone cell culture was also determined by colorimetric, ALP activity, nodule formation, Western blotting, wound-healing, and tartrate-resistant acid phosphatase activity assays. Consequently, the most appropriate weight ratio of RA to RAS for the proliferation and differentiation of osteoblasts was 5 : 1. Moreover, the most effective concentration of DBT was 1,000 μg/mL, which significantly increased the number of osteoblasts, intracellular ALP levels, and nodule numbers, while inhibiting osteoclast activity. Additionally, 1,000 μg/mL of DBT was able to stimulate p-ERK and p-JNK signal pathway. Therefore, DBT is highly promising for use in accelerating fracture healing in the middle or late healing periods. PMID:25295277

  12. Acidic gas capture by diamines

    DOEpatents

    Rochelle, Gary; Hilliard, Marcus

    2011-05-10

    Compositions and methods related to the removal of acidic gas. In particular, the present disclosure relates to a composition and method for the removal of acidic gas from a gas mixture using a solvent comprising a diamine (e.g., piperazine) and carbon dioxide. One example of a method may involve a method for removing acidic gas comprising contacting a gas mixture having an acidic gas with a solvent, wherein the solvent comprises piperazine in an amount of from about 4 to about 20 moles/kg of water, and carbon dioxide in an amount of from about 0.3 to about 0.9 moles per mole of piperazine.

  13. Dipotassium maleate with boric acid.

    PubMed

    Tombul, Mustafa; Guven, Kutalmis; Büyükgüngör, Orhan; Aktas, Huseyin; Durlu, Tahsin Nuri

    2007-09-01

    In the title compound, poly[(mu3-boric acid)-mu4-maleato-dipotassium], [K2(C(4)H(2)O(4)){B(OH)3}]n, there are two independent K+ cations, one bonded to seven O atoms (three from boric acid and four from maleate), and the other eight-coordinate via three boric acid and four maleate O atoms and a weak eta(1)-type coordination to the C=C bond of the maleate central C atoms. Hydrogen bonding links the boric acid ligands and maleate dianions, completing the packing structure.

  14. Organic Acid Production by Basidiomycetes

    PubMed Central

    Takao, Shoichi

    1965-01-01

    Sixty-seven strains belonging to 47 species of Basidiomycetes were examined for their acid-producing abilities in glucose media, in both the presence and absence of CaCO3, in stationary and shake cultures. Some strains were found to produce large quantities of oxalic acid. The oxalic acid-producing strains could be separated into two groups. Strains of one group (mostly brown-rot fungi) were able to produce oxalic acid, regardless of whether CaCO3 was present in the medium. Strains of the other group (mostly white-rot fungi) were characterized by their ability to produce oxalic acid only when CaCO3 was added to the medium. With the latter group, shake-culturing was generally more effective than stationary culturing in respect to acid production. In the CaCO3-containing media, Schizophyllum commune, Merulius tremellosus, and Porodisculus pendulus were found to produce substantial amounts of L-malic acid as a main metabolic product, along with small quantities of oxalic and other acids in shake cultures. Especially, S. commune and M. tremellosus may be employed as malic acid-producing species. PMID:5867653

  15. Preparation and characterization Al3+-bentonite Turen Malang for esterification fatty acid (palmitic acid, oleic acid and linoleic acid)

    NASA Astrophysics Data System (ADS)

    Abdulloh, Abdulloh; Aminah, Nanik Siti; Triyono, Mudasir, Trisunaryanti, Wega

    2016-03-01

    Catalyst preparation and characterization of Al3+-bentonite for esterification of palmitic acid, oleic acid and linoleic acid has been done. Al3+-bentonite catalyst was prepared from natural bentonite of Turen Malang through cation exchange reaction using AlCl3 solution. The catalysts obtained were characterized by XRD, XRF, pyridine-FTIR and surface area analyser using the BET method. Catalyst activity test of Al3+-bentonite for esterification reaction was done at 65°C using molar ratio of metanol-fatty acid of 30:1 and 0.25 g of Al3+-bentonite catalyst for the period of ½, 1, 2, 3, 4 and 5 hours. Based on the characterization results, the Al3+-bentonite Turen Malang catalyst has a d-spacing of 15.63 Ǻ, acid sites of Brönsted and Lewis respectively of 230.79 µmol/g and 99.39 µmol/g, surface area of 507.3 m2/g and the average of radius pore of 20.09 Å. GC-MS analysis results of the oil phase after esterification reaction showed the formation of biodiesel (FAME: Fatty acid methyl ester), namely methyl palmitate, methyl oleate and methyl linoleate. The number of conversions resulted in esterification reaction using Al3+-bentonite Turen Malang catalyst was 74.61%, 37.75%, and 20, 93% for the esterification of palmitic acid, oleic acid and linoleic acid respectively.

  16. Fatty acid-amino acid conjugates diversification in Lepidopteran caterpillars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fatty acid amino acid conjugates (FACs) have been found in Noctuid as well as Sphingid caterpillar oral secretions and especially volicitin [N-(17-hydroxylinolenoyl)-L-Glutamine] and its biochemical precursor, N-linolenoyl-L-glutamine, are known elicitors of induced volatile emissions in corn plants...

  17. Sulfuric acid as autocatalyst in the formation of sulfuric acid.

    PubMed

    Torrent-Sucarrat, Miquel; Francisco, Joseph S; Anglada, Josep M

    2012-12-26

    Sulfuric acid can act as a catalyst of its own formation. We have carried out a computational investigation on the gas-phase formation of H(2)SO(4) by hydrolysis of SO(3) involving one and two water molecules, and also in the presence of sulfuric acid and its complexes with one and two water molecules. The hydrolysis of SO(3) requires the concurrence of two water molecules, one of them acting as a catalyzer, and our results predict an important catalytic effect, ranging between 3 and 11 kcal·mol(-1) when the catalytic water molecule is substituted by a sulfuric acid molecule or one of its hydrates. In these cases, the reaction products are either bare sulfuric acid dimer or sulfuric acid dimer complexed with a water molecule. There are broad implications from these new findings. The results of the present investigation show that the catalytic effect of sulfuric acid in the SO(3) hydrolysis can be important in the Earth's stratosphere, in the heterogeneous formation of sulfuric acid and in the formation of aerosols, in H(2)SO(4) formation by aircraft engines, and also in understanding the formation of sulfuric acid in the atmosphere of Venus.

  18. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances

    PubMed Central

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-01

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

  19. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances.

    PubMed

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-04

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism.

  20. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and Northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  1. Acid rain on acid soil: a new perspective

    SciTech Connect

    Krug, E.C.; Frink, C.R.

    1983-08-05

    Acid rain is widely believed to be responsible for acidifying soil and water in areas of North America and northern Europe. However, factors commonly considered to make landscapes susceptible to acidification by acid rain are the same factors long known to strongly acidify soils through the natural processes of soil formation. Recovery from extreme and widespread careless land use has also occurred in regions undergoing acidification. There is evidence that acidification by acid rain is superimposed on long-term acidification induced by changes in land use and consequent vegetative succession. Thus, the interactions of acid rain, acid soil, and vegetation need to be carefully examined on a watershed basis in assessing benefits expected from proposed reductions in emissions of oxides of sulfur and nitrogen.

  2. Microbial desulfonation of substituted naphthalenesulfonic acids and benzenesulfonic acids.

    PubMed Central

    Zürrer, D; Cook, A M; Leisinger, T

    1987-01-01

    Sulfur-limited batch enrichment cultures containing one of nine multisubstituted naphthalenesulfonates and an inoculum from sewage yielded several taxa of bacteria which could quantitatively utilize 19 sulfonated aromatic compounds as the sole sulfur source for growth. Growth yields were about 4 kg of protein per mol of sulfur. Specific degradation rates were about 4 to 14 mu kat/kg of protein. A Pseudomonas sp., an Arthrobacter sp., and an unidentified bacterium were examined. Each desulfonated at least 16 aromatic compounds, none of which served as a carbon source. Pseudomonas sp. strain S-313 converted 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 5-amino-1-naphthalenesulfonic acid, benzenesulfonic acid, and 3-aminobenzenesulfonic acid to 1-naphthol, 2-naphthol, 5-amino-1-naphthol, phenol, and 3-aminophenol, respectively. Experiments with 18O2 showed that the hydroxyl group was derived from molecular oxygen. PMID:3662502

  3. A comparison of chromic acid and sulfuric acid anodizing

    NASA Technical Reports Server (NTRS)

    Danford, M. D.

    1992-01-01

    Because of federal and state mandates restricting the use of hexavalent chromium, it was deemed worthwhile to compare the corrosion protection afforded 2219-T87 aluminum alloy by both Type I chromic acid and Type II sulfuric acid anodizing per MIL-A-8625. Corrosion measurements were made on large, flat 2219-T87 aluminum alloy sheet material with an area of 1 cm(exp 2) exposed to a corrosive medium of 3.5-percent sodium chloride at pH 5.5. Both ac electrochemical impedance spectroscopy and the dc polarization resistance techniques were employed. The results clearly indicate that the corrosion protection obtained by Type II sulfuric acid anodizing is superior, and no problems should result by substituting Type II sulfuric acid anodizing for Type I chromic acid anodizing.

  4. Carbonic Acid Pretreatment of Biomass

    SciTech Connect

    G. Peter van Walsum; Kemantha Jayawardhana; Damon Yourchisin; Robert McWilliams; Vanessa Castleberry

    2003-05-31

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. 1) Solidify the theoretical understanding of the binary CO2/H2O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. 2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. 3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. 4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. 5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for the use of carbonic

  5. Carbonic Acid Retreatment of Biomass

    SciTech Connect

    Baylor university

    2003-06-01

    This project sought to address six objectives, outlined below. The objectives were met through the completion of ten tasks. (1) Solidify the theoretical understanding of the binary CO{sub 2}/H{sub 2}O system at reaction temperatures and pressures. The thermodynamics of pH prediction have been improved to include a more rigorous treatment of non-ideal gas phases. However it was found that experimental attempts to confirm theoretical pH predictions were still off by a factor of about 1.8 pH units. Arrhenius experiments were carried out and the activation energy for carbonic acid appears to be substantially similar to sulfuric acid. Titration experiments have not yet confirmed or quantified the buffering or acid suppression effects of carbonic acid on biomass. (2) Modify the carbonic acid pretreatment severity function to include the effect of endogenous acid formation and carbonate buffering, if necessary. It was found that the existing severity functions serve adequately to account for endogenous acid production and carbonate effects. (3) Quantify the production of soluble carbohydrates at different reaction conditions and severity. Results show that carbonic acid has little effect on increasing soluble carbohydrate concentrations for pretreated aspen wood, compared to pretreatment with water alone. This appears to be connected to the release of endogenous acids by the substrate. A less acidic substrate such as corn stover would derive benefit from the use of carbonic acid. (4) Quantify the production of microbial inhibitors at selected reaction conditions and severity. It was found that the release of inhibitors was correlated to reaction severity and that carbonic acid did not appear to increase or decrease inhibition compared to pretreatment with water alone. (5) Assess the reactivity to enzymatic hydrolysis of material pretreated at selected reaction conditions and severity. Enzymatic hydrolysis rates increased with severity, but no advantage was detected for

  6. Fatty acids and lymphocyte functions.

    PubMed

    Calder, P C; Yaqoob, P; Thies, F; Wallace, F A; Miles, E A

    2002-01-01

    The immune system acts to protect the host against pathogenic invaders. However, components of the immune system can become dysregulated such that their activities are directed against host tissues, so causing damage. Lymphocytes are involved in both the beneficial and detrimental effects of the immune system. Both the level of fat and the types of fatty acid present in the diet can affect lymphocyte functions. The fatty acid composition of lymphocytes, and other immune cells, is altered according to the fatty acid composition of the diet and this alters the capacity of those cells to produce eicosanoids, such as prostaglandin E2, which are involved in immunoregulation. A high fat diet can impair lymphocyte function. Cell culture and animal feeding studies indicate that oleic, linoleic, conjugated linoleic, gamma-linolenic, dihomo-gamma-linolenic, arachidonic, alpha-linolenic, eicosapentaenoic and docosahexaenoic acids can all influence lymphocyte proliferation, the production of cytokines by lymphocytes, and natural killer cell activity. High intakes of some of these fatty acids are necessary to induce these effects. Among these fatty acids the long chain n-3 fatty acids, especially eicosapentaenoic acid, appear to be the most potent when included in the human diet. Although not all studies agree, it appears that fish oil, which contains eicosapentaenoic acid, down regulates the T-helper 1-type response which is associated with chronic inflammatory disease. There is evidence for beneficial effects of fish oil in such diseases; this evidence is strongest for rheumatoid arthritis. Since n-3 fatty acids also antagonise the production of inflammatory eicosanoid mediators from arachidonic acid, there is potential for benefit in asthma and related diseases. Recent evidence indicates that fish oil may be of benefit in some asthmatics but not others.

  7. Infrared spectra of hydrogen-bonded salicylic acid and its derivatives : Salicylic acid and acetylsalicylic acid

    NASA Astrophysics Data System (ADS)

    Wójcik, Marek J.

    1981-11-01

    Infrared spectra of hydrogen-bonded salicylic acid, O-deutero-salicylic acid and acetylsalicylic acid crystals have been studied experimentally and theoretically. Interpretation of these spectra was based on the Witkowski-Maréchal model. Semi-quantitative agreement between experimental and theoretical spectra can be achieved with the simplest form of this model, with values of interaction parameters transferable for equivalent intermolecular hydrogen bonds.

  8. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc.

  9. Production of Succinic Acid from Citric Acid and Related Acids by Lactobacillus Strains

    PubMed Central

    Kaneuchi, Choji; Seki, Masako; Komagata, Kazuo

    1988-01-01

    A number of Lactobacillus strains produced succinic acid in de Man-Rogosa-Sharpe broth to various extents. Among 86 fresh isolates from fermented cane molasses in Thailand, 30 strains (35%) produced succinic acid; namely, 23 of 39 Lactobacillus reuteri strains, 6 of 18 L. cellobiosus strains, and 1 of 6 unidentified strains. All of 10 L. casei subsp. casei strains, 5 L. casei subsp. rhamnosus strains, 6 L. mali strains, and 2 L. buchneri strains did not produce succinic acid. Among 58 known strains including 48 type strains of different Lactobacillus species, the strains of L. acidophilus, L. crispatus, L. jensenii, and L. parvus produced succinic acid to the same extent as the most active fresh isolates, and those of L. alimentarius, L. collinoides, L. farciminis, L. fructivorans (1 of 2 strains tested), L. malefermentans, and L. reuteri were also positive, to lesser extents. Diammonium citrate in de Man-Rogosa-Sharpe broth was determined as a precursor of the succinic acid produced. Production rates were about 70% on a molar basis with two fresh strains tested. Succinic acid was also produced from fumaric and malic acids but not from dl-isocitric, α-ketoglutaric, and pyruvic acids. The present study is considered to provide the first evidence on the production of succinic acid, an important flavoring substance in dairy products and fermented beverages, from citrate by lactobacilli. PMID:16347795

  10. Synthesis of new kojic acid based unnatural α-amino acid derivatives.

    PubMed

    Balakrishna, C; Payili, Nagaraju; Yennam, Satyanarayana; Devi, P Uma; Behera, Manoranjan

    2015-11-01

    An efficient method for the preparation of kojic acid based α-amino acid derivatives by alkylation of glycinate schiff base with bromokojic acids have been described. Using this method, mono as well as di alkylated kojic acid-amino acid conjugates have been prepared. This is the first synthesis of C-linked kojic acid-amino acid conjugate where kojic acid is directly linked to amino acid through a C-C bond.

  11. Getting Back to Basics (& Acidics)

    ERIC Educational Resources Information Center

    Rhodes, Sam

    2006-01-01

    This article describes a few novel acid-base experiments intended to introduce students to the basic concepts of acid-base chemistry and provide practical examples that apply directly to the study of biology and the human body. Important concepts such as the reaction between carbon dioxide and water, buffers and protein denaturation, are covered.…

  12. Synthesis of pyromellitic acid esters

    NASA Technical Reports Server (NTRS)

    Fedorova, V. A.; Donchak, V. A.; Martynyuk-Lototskaya, A. N.

    1985-01-01

    The ester acids necessary for studyng the thermochemical properties of pyromellitic acid (PMK)-based peroxides were investigated. Obtaining a tetramethyl ester of a PMK was described. The mechanism of an esterification reaction is discussed, as is the complete esterification of PMK with primary alcohol.

  13. Acid Rain: What's the Forecast?

    ERIC Educational Resources Information Center

    Bybee, Rodger

    1984-01-01

    Discusses various types of acid rain, considered to be a century-old problem. Topics include: wet and dry deposition, effects on a variety of environments, ecosystems subject to detrimental effects, and possible solutions to the problem. A list of recommended resources on acid rain is provided. (BC)

  14. Acid Rain: An Educational Opportunity?

    ERIC Educational Resources Information Center

    Marion, James I.

    1984-01-01

    Deals with how educators can handle the subject of acid rain; illustrates suggestions with experiences of grade nine students visiting Frost Valley Environmental Education Center (Oliverea, New York) to learn scientific concepts through observation of outdoor phenomena, including a stream; and discusses acid rain, pH levels, and pollution control…

  15. Acid Precipitation: Causes and Consequences.

    ERIC Educational Resources Information Center

    Babich, Harvey; And Others

    1980-01-01

    This article is the first of three articles in a series on the acid rain problem in recent years. Discussed are the causes of acid precipitation and its consequences for the abiotic and biotic components of the terrestrial and aquatic ecosystems, and for man-made materials. (Author/SA)

  16. Acid rain & electric utilities II

    SciTech Connect

    1997-12-31

    This document presents reports which were presented at the Acid Rain and Electric Utilities Conference. Topics include environmental issues and electric utilities; acid rain program overview; global climate change and carbon dioxide; emissions data management; compliance; emissions control; allowance and trading; nitrogen oxides; and assessment. Individual reports have been processed separately for the United States Department of Energy databases.

  17. Acid Rain: The Scientific Challenge.

    ERIC Educational Resources Information Center

    Godfrey, Paul J.

    1991-01-01

    Documents the workings and findings of the Massachusetts Acid Rain Monitoring Project, which has pooled the volunteer efforts of more than 1,000 amateur and professional scientists since 1983. Reports on the origins of air pollution, the prediction of acid rain, and its effects on both water life and land resources. (JJK)

  18. Beneficial effects of hyaluronic acid.

    PubMed

    Sudha, Prasad N; Rose, Maximas H

    2014-01-01

    Biomaterials are playing a vital role in our day-to-day life. Hyaluronan (hyaluronic acid), a biomaterial, receives special attention among them. Hyaluronic acid (HA) is a polyanionic natural polymer occurring as linear polysaccharide composed of glucuronic acid and N-acetylglucosamine repeats via a β-1,4 linkage. It is the most versatile macromolecule present in the connective tissues of all vertebrates. Hyaluronic acid has a wide range of applications with its excellent physicochemical properties such as biodegradability, biocompatibility, nontoxicity, and nonimmunogenicity and serves as an excellent tool in biomedical applications such as osteoarthritis surgery, ocular surgery, plastic surgery, tissue engineering, and drug delivery. It plays a key role in cushioning and lubricating the body and is abundant in the eyes, joints, and heart valves. A powerful antioxidant, hyaluronic acid is perhaps best known for its ability to bond water to tissue. Hyaluronan production increases in proliferating cells, and the polymer may play a role in mitosis. This chapter gives an overview of hyaluronic acid and its physicochemical properties and applications. This chapter gives a deep understanding on the special benefits of hyaluronic acid in the fields of pharmaceutical, medical, and environmental applications. Hyaluronic acid paves the way for beneficial research and applications to the welfare of life forms.

  19. Phosphorus derivatives of salicylic acid

    NASA Astrophysics Data System (ADS)

    Chvertkina, L. V.; Khoklov, P. S.; Mironov, Vladimir F.

    1992-10-01

    The present state of work on the methods of synthesis, chemical properties, and practical applications of phosphorus-containing derivatives of salicylic acid has been reviewed. The characteristics of the chemical transformations of cyclic and acyclic phosphorus derivatives of salicylic acid related to the coordination state of the phosphorus atom have been examined. The bibliography includes 158 references.

  20. Protein and amino acid nutrition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dairy cow protein and amino acid nutrition have a significant role in sustainable dairying. Protein, amino acids, and nitrogen are inextricably linked through effects in the rumen, metabolism of the cow, and environmental nutrient management. Feeding systems have been making progress toward emphasiz...

  1. Acid Tests and Basic Fun.

    ERIC Educational Resources Information Center

    McBride, John W.

    1995-01-01

    Explores acids and bases using different indicators, such as turmeric, purple grape juice, and lichens. Because some of these indicators are not as sensitive as cabbage juice or litmus paper, determining to which acids and bases each indicator is sensitive presents an enjoyable, problem-solving challenge for students. Presents directions for…

  2. Acid Ceramidase in Melanoma

    PubMed Central

    Realini, Natalia; Palese, Francesca; Pizzirani, Daniela; Pontis, Silvia; Basit, Abdul; Bach, Anders; Ganesan, Anand; Piomelli, Daniele

    2016-01-01

    Acid ceramidase (AC) is a lysosomal cysteine amidase that controls sphingolipid signaling by lowering the levels of ceramides and concomitantly increasing those of sphingosine and its bioactive metabolite, sphingosine 1-phosphate. In the present study, we evaluated the role of AC-regulated sphingolipid signaling in melanoma. We found that AC expression is markedly elevated in normal human melanocytes and proliferative melanoma cell lines, compared with other skin cells (keratinocytes and fibroblasts) and non-melanoma cancer cells. High AC expression was also observed in biopsies from human subjects with Stage II melanoma. Immunofluorescence studies revealed that the subcellular localization of AC differs between melanocytes (where it is found in both cytosol and nucleus) and melanoma cells (where it is primarily localized to cytosol). In addition to having high AC levels, melanoma cells generate lower amounts of ceramides than normal melanocytes do. This down-regulation in ceramide production appears to result from suppression of the de novo biosynthesis pathway. To test whether AC might contribute to melanoma cell proliferation, we blocked AC activity using a new potent (IC50 = 12 nm) and stable inhibitor. AC inhibition increased cellular ceramide levels, decreased sphingosine 1-phosphate levels, and acted synergistically with several, albeit not all, antitumoral agents. The results suggest that AC-controlled sphingolipid metabolism may play an important role in the control of melanoma proliferation. PMID:26553872

  3. Lead-acid battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1983-01-01

    A light weight lead-acid battery (30) having a positive terminal (36) and a negative terminal (34) and including one or more cells or grid stacks having a plurality of vertically stacked conductive monoplates (10, 20) with positive active material and negative active material deposited on alternating plates in the cell or grid stack. Electrolyte layers (26, 28) positioned between each monoplate are included to provide a battery cell having four sides which is capable of being electrically charged and discharged. Two vertical positive bus bars (42, 43) are provided on opposite sides of the battery cell for connecting the monoplates (10) with positive active material together in parallel current conducting relation. In addition, two negative bus bars (38, 39) on opposite sides of the battery cell each being adjacent the positive bus bars are provided for connecting the monoplates (20) with negative active material together in parallel current conducting relation. The positive (42, 43) and negative (38, 39) bus bars not only provide a low resistance method for connecting the plurality of conductive monoplates of their respective battery terminals (36, 34) but also provides support and structural strength to the battery cell structure. In addition, horizontal orientation of monoplates (10, 20) is provided in a vertical stacking arrangement to reduce electrolyte stratification and short circuiting due to flaking of positive and negative active materials from the monoplates.

  4. Fumaric acid production by fermentation

    PubMed Central

    Roa Engel, Carol A.; Zijlmans, Tiemen W.; van Gulik, Walter M.; van der Wielen, Luuk A. M.

    2008-01-01

    The potential of fumaric acid as a raw material in the polymer industry and the increment of cost of petroleum-based fumaric acid raises interest in fermentation processes for production of this compound from renewable resources. Although the chemical process yields 112% w/w fumaric acid from maleic anhydride and the fermentation process yields only 85% w/w from glucose, the latter raw material is three times cheaper. Besides, the fermentation fixes CO2. Production of fumaric acid by Rhizopus species and the involved metabolic pathways are reviewed. Submerged fermentation systems coupled with product recovery techniques seem to have achieved economically attractive yields and productivities. Future prospects for improvement of fumaric acid production include metabolic engineering approaches to achieve low pH fermentations. PMID:18214471

  5. Atmospheric dust and acid rain

    SciTech Connect

    Hedin, L.O.; Likens, G.E.

    1996-12-01

    Why is acid rain still an environmental problem in Europe and North America despite antipollution reforms? The answer really is blowing in the wind: atmospheric dust. These airborne particles can help neutralize the acids falling on forests, but dust levels are unusually low these days. In the air dust particles can neutralize acid rain. What can we do about acid rain and atmospheric dust? Suggestions range from the improbable to the feasible. One reasonable suggestion is to reduce emissions of acidic pollutants to levels that can be buffered by natural quantities of basic compounds in the atmosphere; such a goal would mean continued reductions in sulfur dioxide and nitrogen oxides, perhaps even greater than those prescribed in the 1990 Amendments to the Clean Air Act in the U.S. 5 figs.

  6. SIALIC ACIDS AND AUTOIMMUNE DISEASE

    PubMed Central

    Mahajan, Vinay S.; Pillai, Shiv

    2016-01-01

    summary An important underlying mechanism that contributes to autoimmunity is the loss of inhibitory signaling in the immune system. Sialic acid-recognizing Ig superfamily lectins or Siglecs are a family of cell surface proteins largely expressed in hematopoietic cells. The majority of Siglecs are inhibitory receptors expressed in immune cells that bind to sialic acid containing ligands and recruit SH2-domain containing tyrosine phosphatases to their cytoplasmic tails. They deliver inhibitory signals that can contribute to the constraining of immune cells and thus protect the host from autoimmunity. The inhibitory functions of CD22/Siglec-2 and Siglec-G and their contributions to tolerance and autoimmunity, primarily in the B lymphocyte context, are considered in some detail in this review. The relevance to autoimmunity and unregulated inflammation of modified sialic acids, enzymes that modify sialic acid, and other sialic acid binding proteins are also reviewed. PMID:26683151

  7. Reduction of hypervalent chromium in acidic media by alginic acid.

    PubMed

    Bertoni, Fernando A; Bellú, Sebastian E; González, Juan C; Sala, Luis F

    2014-12-19

    Selective oxidation of carboxylate groups present in alginic acid by Cr(VI) affords CO2, oxidized alginic acid, and Cr(III) as final products. The redox reaction afforded first-order kinetics in [alginic acid], [Cr(VI)], and [H(+)], at fixed ionic strength and temperature. Kinetic studies showed that the redox reaction proceeds through a mechanism which combines Cr(VI)→Cr(IV)→Cr(II) and Cr(VI)→Cr(IV)→Cr(III) pathways. The mechanism was supported by the observation of free radicals, CrO2(2+) and Cr(V) as reaction intermediates. The reduction of Cr(IV) and Cr(V) by alginic acid was independently studied and it was found to occur more than 10(3) times faster than alginic acid/Cr(VI) reaction, in acid media. At pH 1-3, oxo-chromate(V)-alginic acid species remain in solution during several hours at 15°C. The results showed that this abundant structural polysaccharide present on brown seaweeds is able to reduce Cr(VI/V/IV) or stabilize high-valent chromium depending on pH value.

  8. Acid hydrolysis of sugarcane bagasse for lactic acid production.

    PubMed

    Laopaiboon, Pattana; Thani, Arthit; Leelavatcharamas, Vichean; Laopaiboon, Lakkana

    2010-02-01

    In order to use sugarcane bagasse as a substrate for lactic acid production, optimum conditions for acid hydrolysis of the bagasse were investigated. After lignin extraction, the conditions were varied in terms of hydrochloric (HCl) or sulfuric (H(2)SO(4)) concentration (0.5-5%, v/v), reaction time (1-5h) and incubation temperature (90-120 degrees C). The maximum catalytic efficiency (E) was 10.85 under the conditions of 0.5% of HCl at 100 degrees C for 5h, which the main components (in gl(-1)) in the hydrolysate were glucose, 1.50; xylose, 22.59; arabinose, 1.29; acetic acid, 0.15 and furfural, 1.19. To increase yield of lactic acid production from the hydrolysate by Lactococcus lactis IO-1, the hydrolysate was detoxified through amberlite and supplemented with 7 g l(-1) of xylose and 7 g l(-1) of yeast extract. The main products (in gl(-1)) of the fermentation were lactic acid, 10.85; acetic acid, 7.87; formic acid, 6.04 and ethanol, 5.24.

  9. Acid soil and acid rain, 2nd edition

    SciTech Connect

    Kennedy, I.R.

    1992-01-01

    This book examines the basic chemical processes involved in acidification in order to better assess their long-term effects on the status of soils, the health of plants and other living species that depend on them. It also discusses acidity, pH and protons their significance in bioenergetics and the consequent role of autotrophic organisms in acidifying ecosystems. This edition incorporates and integrates recent findings that render more explanations of the causes of the environmental impacts of acidity, especially in forests and lakes. Also explores current research into acid rain and soil in order to devise appropriate measures for their amelioration.

  10. Fatty acid composition of selected prosthecate bacteria.

    PubMed

    Carter, R N; Schmidt, J M

    1976-10-11

    The cellular fatty acid composition of 14 strains of Caulobacter speices and types, two species of Prosthecomicrobium, and two species of Asticcacaulis was determined by gas-liquid chromatography. In most of these bacteria, the major fatty acids were octadecenoic acid (C18:1), hexadecenoic acid (C16:1) and hexadecanoic acid (C16:0). Some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. Hydroxytetradecanoic acid was an important component of P.enhydrum but significant amounts of hydroxy acids were not detected in other prosthecate bacteria examined.

  11. Functional nucleic acid probes and uses thereof

    DOEpatents

    Nilsen-Hamilton, Marit

    2006-10-03

    The present invention provides functional nucleic acid probes, and methods of using functional nucleic acid probes, for binding a target to carry out a desired function. The probes have at least one functional nucleic acid, at least one regulating nucleic acid, and at least one attenuator. The functional nucleic acid is maintained in an inactive state by the attenuator and activated by the regulating nucleic acid only in the presence of a regulating nucleic acid target. In its activated state the functional nucleic acid can bind to its target to carry out a desired function, such as generating a signal, cleaving a nucleic acid, or catalyzing a reaction.

  12. Evaluation of clastogenicity of formic acid, acetic acid and lactic acid on cultured mammalian cells.

    PubMed

    Morita, T; Takeda, K; Okumura, K

    1990-03-01

    Using Chinese hamster ovary K1 cells, chromosomal aberration tests were carried out with formic acid, acetic acid and lactic acid, and the relationship between the pH of the medium and the clastogenic activity was examined. The medium used was Ham's F12 supplemented with 17 mM NaHCO3 and 10% fetal calf serum. All of these acids induced chromosomal aberrations at the initial pH of ca. 6.0 or below (about 10-14 mM of each acid) both with and without S9 mix. Exposure of cells to about pH 5.7 or below (about 12-16 mM of each acid) was found to be toxic. When the culture medium was first acidified with each of these acids and then neutralized to pH 6.4 or pH 7.2 with NaOH, no clastogenic activity was observed. Using F12 medium supplemented with 34 mM NaHCO3 as a buffer, no clastogenic activity was observed at doses up to 25 mM of these acids (initial pH 5.8-6.0). However, it was found that about 10% of the cells had aberrations at pH 5.7 or below (27.5-32.5 mM of each acid). Furthermore, when 30 mM HEPES was used as a buffer, chromosomal aberrations were not induced at doses up to 20 mM formic acid and acetic acid (initial pH 7.0-7.1), and at doses up to 30 mM lactic acid (initial pH 6.6). In the initial pH range of 6.4-6.7 (25-32.5 mM of each acid), chromosomal aberrations were observed. The above results show that these acids themselves are non-clastogenic, and the pseudo-positive reactions attributable to non-physiological pH could be eliminated by either neutralization of the treatment medium or enhancement of the buffering ability.

  13. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  14. 21 CFR 184.1007 - Aconitic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Aconitic acid. 184.1007 Section 184.1007 Food and... Substances Affirmed as GRAS § 184.1007 Aconitic acid. (a) Aconitic acid (1,2,3-propenetricarboxylic acid... Ranunculaceae. Transaconitic acid can be isolated during sugarcane processing, by precipitation as the...

  15. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and....1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid occurs naturally are...

  16. 21 CFR 184.1025 - Caprylic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Caprylic acid. 184.1025 Section 184.1025 Food and....1025 Caprylic acid. (a) Caprylic acid is the chemical name for octanoic acid. It is considered to be a short or medium chain fatty acid. It occurs normally in various foods and is commercially prepared...

  17. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  18. 21 CFR 184.1025 - Caprylic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Caprylic acid. 184.1025 Section 184.1025 Food and... Substances Affirmed as GRAS § 184.1025 Caprylic acid. (a) Caprylic acid is the chemical name for octanoic acid. It is considered to be a short or medium chain fatty acid. It occurs normally in various...

  19. 21 CFR 184.1025 - Caprylic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Caprylic acid. 184.1025 Section 184.1025 Food and... Substances Affirmed as GRAS § 184.1025 Caprylic acid. (a) Caprylic acid is the chemical name for octanoic acid. It is considered to be a short or medium chain fatty acid. It occurs normally in various...

  20. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  1. 21 CFR 184.1021 - Benzoic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Benzoic acid. 184.1021 Section 184.1021 Food and... Substances Affirmed as GRAS § 184.1021 Benzoic acid. (a) Benzoic acid is the chemical benzenecarboxylic acid (C7H6O2), occurring in nature in free and combined forms. Among the foods in which benzoic acid...

  2. 21 CFR 184.1025 - Caprylic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Caprylic acid. 184.1025 Section 184.1025 Food and... Substances Affirmed as GRAS § 184.1025 Caprylic acid. (a) Caprylic acid is the chemical name for octanoic acid. It is considered to be a short or medium chain fatty acid. It occurs normally in various...

  3. 21 CFR 184.1007 - Aconitic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Aconitic acid. 184.1007 Section 184.1007 Food and... Substances Affirmed as GRAS § 184.1007 Aconitic acid. (a) Aconitic acid (1,2,3-propenetricarboxylic acid... Ranunculaceae. Transaconitic acid can be isolated during sugarcane processing, by precipitation as the...

  4. 21 CFR 184.1007 - Aconitic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Aconitic acid. 184.1007 Section 184.1007 Food and....1007 Aconitic acid. (a) Aconitic acid (1,2,3-propenetricarboxylic acid (C6H6O6), CAS Reg. No. 000499-12... acid can be isolated during sugarcane processing, by precipitation as the calcium salt from cane...

  5. 21 CFR 189.155 - Monochloroacetic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Monochloroacetic acid. 189.155 Section 189.155... Human Food § 189.155 Monochloroacetic acid. (a) Monochloroacetic acid is the chemical chloroacetic acid... in alcoholic and nonalcoholic beverages. Monochloroacetic acid is permitted in food package...

  6. 21 CFR 184.1007 - Aconitic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Aconitic acid. 184.1007 Section 184.1007 Food and... Substances Affirmed as GRAS § 184.1007 Aconitic acid. (a) Aconitic acid (1,2,3-propenetricarboxylic acid... Ranunculaceae. Transaconitic acid can be isolated during sugarcane processing, by precipitation as the...

  7. 21 CFR 184.1025 - Caprylic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Caprylic acid. 184.1025 Section 184.1025 Food and... Substances Affirmed as GRAS § 184.1025 Caprylic acid. (a) Caprylic acid is the chemical name for octanoic acid. It is considered to be a short or medium chain fatty acid. It occurs normally in various...

  8. 21 CFR 184.1007 - Aconitic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Aconitic acid. 184.1007 Section 184.1007 Food and... Substances Affirmed as GRAS § 184.1007 Aconitic acid. (a) Aconitic acid (1,2,3-propenetricarboxylic acid... Ranunculaceae. Transaconitic acid can be isolated during sugarcane processing, by precipitation as the...

  9. 21 CFR 184.1097 - Tannic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Tannic acid. 184.1097 Section 184.1097 Food and....1097 Tannic acid. (a) Tannic acid (CAS Reg. No. 1401-55-4), or hydrolyzable gallotannin, is a complex polyphenolic organic structure that yields gallic acid and either glucose or quinic acid as hydrolysis...

  10. Characterization of carbon-sulfur bond cleavage by axenic and mixed cultures of Rhodococcus rhodochrous IGTS8

    SciTech Connect

    Kayser, K.J.; Bielaga, B.A.; Jackowski, K.; Oduson, O.; Kilbane, J. II

    1992-12-31

    Growth assays reveal that Rhodococcus rhodochrous IGTS8 can utilize a wide range of organosulfur compounds as the sole source of sulfur. Compounds that are utilized include thiophenes, sulfides, disulfides, mercaptans, sulfoxides, and sulfones. None of the organosulfur compounds tested can serve as a carbon source. A convenient spectrophotometric assay (Gibbs assay) based on the chromogenic reaction of 2,6-dichloroquinone-4-chloroimide with aromatic hydroxyl groups was developed and used in conjunction with GC/MS analysis to examine the kinetics of carbon-sulfur bond cleavage by axenic and mixed cell cultures of Rhodococcus rhodochrous IGTS8. The desulfurization trait is expressed at uniform levels during the mid-exponential phase, reaches a maximum during idiophase, and then declines in stationary-phase cells. Desulfurization rates for dibenzothiophene (DBT) range from 8 to 15 {mu}M of DBT/10{sup 12} cells/hour. Mixtures of genetically marked Rhodococcus rhodochrous IGTS8 and an organisms incapable of cleaning carbon-sulfur bonds in relevant test compounds, Enterobacter cloacae, were prepared in ratios that varied over six orders of magnitude. Growth studies revealed that Enterobacter cloacae was able to gain access to sulfur liberated from organosulfur compounds by IGTS8; however, cell-to-cell contact was required. These data also indicate that the desulfurization activity of IGTS8 cells in mixed cultures may be as much as 200-fold higher than in axenic cultures.

  11. Catalytic Emulsion Based on Janus Nanosheets for Ultra-Deep Desulfurization.

    PubMed

    Xia, Lixin; Zhang, Hairan; Wei, Zhichao; Jiang, Yi; Zhang, Ling; Zhao, Jie; Zhang, Junhui; Dong, Li; Li, Erni; Ruhlmann, Laurent; Zhang, Qian

    2017-02-03

    Catalytic Janus nanosheets were synthesized by using an anion-exchange reaction between heteropolyacids (HPAs) and the modified ionic-liquid (IL) moieties of Janus nanosheets. Their morphology and surface properties were characterized by using SEM, energy-dispersive spectroscopy (EDS), FTIR spectroscopy, and X-ray photoelectron spectroscopy (XPS) studies. Because of their inherent Janus structure, the nanosheets exhibited good amphipathic character with ILs and oil to form a stable ILs-in-oil emulsion. Therefore, these Janus nanosheets can be used as both emulsifiers and catalysts to perform emulsive desulfurization. During this process, sulfur-containing compounds at the interface could be easily oxidized and efficiently removed from a model oil. Application of this Janus emulsion brings an efficient, useful, and green procedure to the desulfurization process. Compared with the desulfurization catalyzed by using HPAs in a conventional two-phase system, the sulfur removal of dibenzothiophene (DBT) achieved in a Janus emulsion system was improved from 68 to 97 % within 1.5 h. Moreover, this emulsion system could be demulsified easily by simple centrifugation to recover both the nanosheets and the ILs. Owing to the good structural stability of the Janus nanosheets, the sulfur removal efficiency of DBT could still reach 99.9 % after the catalytic nanosheets had been recycled at least six times.

  12. Attapulgite-CeO2/MoS2 ternary nanocomposite for photocatalytic oxidative desulfurization

    NASA Astrophysics Data System (ADS)

    Li, Xiazhang; Zhang, Zuosong; Yao, Chao; Lu, Xiaowang; Zhao, Xiaobing; Ni, Chaoying

    2016-02-01

    Novel attapulgite(ATP)-CeO2/MoS2 ternary nanocomposites were synthesized by microwave assisted assembly method. The structures of the nanocomposites were characterized by XRD, FT-IR, UV-vis, XPS and in situ TEM. The photocatalytic activities of ATP-CeO2/MoS2 composites were investigated by degradating dibenzothiophene (DBT) in gasoline under visible light irradiation. The effect of the mass ratio of CeO2 to MoS2 on photocatalytic activity was investigated. The results indicate that the three-dimensional network structure is firmly constructed by ATP skeleton, CeO2 particles and MoS2 nanosheet which effectively increase the surface area of the composites and promote the separation of electrons and holes by resulting electronic transmission channels of multi-channel in space. The degradation rate of DBT can reach 95% under 3 h irradiation when the mass ratio of CeO2/MoS2 is 4/10. A plausible mechanism for the photocatalytic oxidative desulfurization of this nanocomposite is put forward.

  13. Performance and microbial community dynamics in bioaugmented aerated filter reactor treating with coking wastewater.

    PubMed

    Shi, Shengnan; Qu, Yuanyuan; Ma, Qiao; Zhang, XuWang; Zhou, Jiti; Ma, Fang

    2015-08-01

    In this study, zeolite-biological aerated filters (Z-BAFs) bioaugmented by free and magnetically immobilized cells of Arthrobacter sp. W1 were designed to treat coking wastewater containing high concentrations of phenol and naphthalene along with carbazole (CA), dibenzofuran (DBF), and dibenzothiophene (DBT). All treatments were carried out for a period of 100days and the data indicated that bioaugmented Z-BAFs with magnetically immobilized cells was most efficient for treating coking wastewaters. Illumina high-throughput sequencing was used to reveal the microbial community structures of Z-BAFs. Both bioaugmentation treatments could accelerate the shift of the bacterial community structures. The introduced strain W1 remained dominant in the bioaugmented Z-BAFs with magnetically immobilized cells, indicating both strain W1 and the indigenous degrading bacteria played the most significant role in the treatment. Overall, bioaugmented Z-BAF with magnetically immobilized cells can be used to efficiently degrade phenol, naphthalene, CA, DBF, and DBT in coking wastewater.

  14. Kinetics for simultaneous HDS, HDN and hydrogenation model reactions. Comparison between Ni-Mo/Al sub 2 O sub 3 and Co-Mo/Al sub 2 O sub 3 catalysts

    SciTech Connect

    Zeuthen, P.H.; Stoltze, P.; Bartholdy, J. )

    1987-04-01

    A kinetic analysis of simultaneous hydrodesulfurization (HDS) of dibenzothiophene (DBT), hydrodenitrogenation (HDN) of indole (IN) and hydrogenation (HYD) of naphthalene (NAP) has been carried out. These compounds represent the major functional groups in heavy petroleum feeds. The goal of these experiments is to study the commercial catalysts with more complex feedstocks. A specific purpose is to determine the competitive inhibition effects of the various reactants. Kinetic data were generated over standard NiMo/Al{sub 2}O{sub 3} and CoMo/Al{sub 2}O{sub 3} catalysts at temperatures of 260 to 350{degree}C. The partial pressures of hydrogen and the other reactants were varied individually. From the data, a kinetic model is developed based on the competitive chemisorption of reactants, intermediates and products on identical surface sites. The kinetic model developed accounts for the appearance of the products and rate of disappearance of DBT, NAP and IN. It is found that sulfur, nitrogen, aromatics and aliphatic-containing compounds adsorb at very different strength. On the basis of these results, it is shown that CoMo/Al{sub 2}O{sub 3} catalyst is more sensitive to adsorbates than the NiMo/Al{sub 2}O{sub 3} catalyst.

  15. Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance

    SciTech Connect

    Zhang, Shuna; Zhang, Shujuan; Song, Limin; Wu, Xiaoqing; Fang, Sheng

    2014-05-01

    Graphical abstract: Three-dimensional interconnected nickel phosphide networks with hollow microstructures and desulfurization performance. - Highlights: • Three-dimensional Ni{sub 2}P has been prepared using foam nickel as a template. • The microstructures interconnected and formed sponge-like porous networks. • Three-dimensional Ni{sub 2}P shows superior hydrodesulfurization activity. - Abstract: Three-dimensional microstructured nickel phosphide (Ni{sub 2}P) was fabricated by the reaction between foam nickel (Ni) and phosphorus red. The as-prepared Ni{sub 2}P samples, as interconnected networks, maintained the original mesh structure of foamed nickel. The crystal structure and morphology of the as-synthesized Ni{sub 2}P were characterized by X-ray diffraction, scanning electron microscopy, automatic mercury porosimetry and X-ray photoelectron spectroscopy. The SEM study showed adjacent hollow branches were mutually interconnected to form sponge-like networks. The investigation on pore structure provided detailed information for the hollow microstructures. The growth mechanism for the three-dimensionally structured Ni{sub 2}P was postulated and discussed in detail. To investigate its catalytic properties, SiO{sub 2} supported three-dimensional Ni{sub 2}P was prepared successfully and evaluated for the hydrodesulfurization (HDS) of dibenzothiophene (DBT). DBT molecules were mostly hydrogenated and then desulfurized by Ni{sub 2}P/SiO{sub 2}.

  16. Terahertz spectrum of gallic acid

    NASA Astrophysics Data System (ADS)

    Wu, Meng; Zhao, Guozhong; Wang, Haiyan; Liang, Chengshen

    2009-11-01

    Gallic acid is natural polyphenol compound found in many green plants. More and more experiments have demonstrated that the gallic acid has comprehensive applications. In the field of medicine, the gallic acid plays an important role in antianaphylaxis, antineoplastic, antimycotic, anti-inflammatory, antivirotic, antiasthmatic and inhibiting the degradation of insulin. It also has a lot of applications in chemical industry, food industry and light industry. So it is important to study the terahertz time-domain spectroscopy of gallic acid. Terahertz time-domain spectroscopy (THz-TDS) is a new coherent spectral technology based on the femtosecond laser. In this work, the spectral characteristics of gallic acid in the range of 0.4 THz to 2.6 THz have been measured by THz-TDS. We obtained its absorption and refraction spectra at room temperature. The vibration absorption spectrum of the single molecule between 0.4 THz and 2.6 THz is simulated based on the Density Functional Theory (DFT). It is found that the gallic acid has the spectral response to THz wave in this frequency range. The results show the abnormal dispersion at 1.51 THz and 2.05 THz. These results can be used in the qualitative analysis of gallic acid and the medicine and food inspection.

  17. Diabetes and Alpha Lipoic Acid

    PubMed Central

    Golbidi, Saeid; Badran, Mohammad; Laher, Ismail

    2011-01-01

    Diabetes mellitus is a multi-faceted metabolic disorder where there is increased oxidative stress that contributes to the pathogenesis of this debilitating disease. This has prompted several investigations into the use of antioxidants as a complementary therapeutic approach. Alpha lipoic acid, a naturally occurring dithiol compound which plays an essential role in mitochondrial bioenergetic reactions, has gained considerable attention as an antioxidant for use in managing diabetic complications. Lipoic acid quenches reactive oxygen species, chelates metal ions, and reduces the oxidized forms of other antioxidants such as vitamin C, vitamin E, and glutathione. It also boosts antioxidant defense system through Nrf-2-mediated antioxidant gene expression and by modulation of peroxisome proliferator activated receptors-regulated genes. ALA inhibits nuclear factor kappa B and activates AMPK in skeletal muscles, which in turn have a plethora of metabolic consequences. These diverse actions suggest that lipoic acid acts by multiple mechanisms, many of which have only been uncovered recently. In this review we briefly summarize the known biochemical properties of lipoic acid and then discussed the oxidative mechanisms implicated in diabetic complications and the mechanisms by which lipoic acid may ameliorate these reactions. The findings of some of the clinical trials in which lipoic acid administration has been tested in diabetic patients during the last 10 years are summarized. It appears that the clearest benefit of lipoic acid supplementation is in patients with diabetic neuropathy. PMID:22125537

  18. Phytic acid in green leaves.

    PubMed

    Hadi Alkarawi, H; Zotz, G

    2014-07-01

    Phytic acid or phytate, the free-acid form of myo-inositolhexakiphosphate, is abundant in many seeds and fruits, where it represents the major storage form of phosphorus. Although also known from other plant tissues, available reports on the occurrence of phytic acid, e.g. in leaves, have never been compiled, nor have they been critically reviewed. We found 45 published studies with information on phytic acid content in leaves. Phytic acid was almost always detected when studies specifically tried to detect it, and accounted for up to 98% of total P. However, we argue that such extreme values, which rival findings from storage organs, are dubious and probably result from measurement errors. Excluding these high values from further quantitative analysis, foliar phytic acid-P averaged 2.3 mg·g(-1) , and represented, on average, 7.6% of total P. Remarkably, the ratio of phytic acid-P to total P did not increase with total P, we even detected a negative correlation of the two variables within one species, Manihot esculenta. This enigmatic finding warrants further attention.

  19. Determination of polyfluoroalkyl phosphoric acid diesters, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, perfluoroalkyl carboxylic acids, and perfluoroalkane sulfonic acids in lake trout from the Great Lakes region.

    PubMed

    Guo, Rui; Reiner, Eric J; Bhavsar, Satyendra P; Helm, Paul A; Mabury, Scott A; Braekevelt, Eric; Tittlemier, Sheryl A

    2012-11-01

    A comprehensive method to extract perfluoroalkyl carboxylic acids, perfluoroalkane sulfonic acids, perfluoroalkyl phosphonic acids, perfluoroalkyl phosphinic acids, and polyfluoroalkyl phosphoric acid diesters simultaneously from fish samples has been developed. The recoveries of target compounds ranged from 78 % to 121 %. The new method was used to analyze lake trout (Salvelinus namaycush) from the Great Lakes region. The results showed that the total perfluoroalkane sulfonate concentrations ranged from 0.1 to 145 ng/g (wet weight) with perfluorooctane sulfonate (PFOS) as the dominant contaminant. Concentrations in fish between lakes were in the order of Lakes Ontario ≈ Erie > Huron > Superior ≈ Nipigon. The total perfluoroalkyl carboxylic acid concentrations ranged from 0.2 to 18.2 ng/g wet weight. The aggregate mean perfluorooctanoic acid (PFOA) concentration in fish across all lakes was 0.045 ± 0.023 ng/g. Mean concentrations of PFOA were not significantly different (p > 0.1) among the five lakes. Perfluoroalkyl phosphinic acids were detected in lake trout from Lake Ontario, Lake Erie, and Lake Huron with concentration ranging from non-detect (ND) to 0.032 ng/g. Polyfluoroalkyl phosphoric acid diesters were detected only in lake trout from Lake Huron, at levels similar to perfluorooctanoic acid.

  20. Pyroligneous acid-the smoky acidic liquid from plant biomass.

    PubMed

    Mathew, Sindhu; Zakaria, Zainul Akmar

    2015-01-01

    Pyroligneous acid (PA) is a complex highly oxygenated aqueous liquid fraction obtained by the condensation of pyrolysis vapors, which result from the thermochemical breakdown or pyrolysis of plant biomass components such as cellulose, hemicellulose, and lignin. PA produced by the slow pyrolysis of plant biomass is a yellowish brown or dark brown liquid with acidic pH and usually comprises a complex mixture of guaiacols, catechols, syringols, phenols, vanillins, furans, pyrans, carboxaldehydes, hydroxyketones, sugars, alkyl aryl ethers, nitrogenated derivatives, alcohols, acetic acid, and other carboxylic acids. The phenolic components, namely guaiacol, alkyl guaiacols, syringol, and alkyl syringols, contribute to the smoky odor of PA. PA finds application in diverse areas, as antioxidant, antimicrobial, antiinflammatory, plant growth stimulator, coagulant for natural rubber, and termiticidal and pesticidal agent; is a source for valuable chemicals; and imparts a smoky flavor for food.

  1. Tropospheric cycle of nitrous acid

    NASA Astrophysics Data System (ADS)

    Harrison, Roy M.; Peak, John D.; Collins, Gareth M.

    1996-06-01

    Measurements of the land surface exchange of nitrous acid over grass and sugar beet surfaces reveal both upward and downward fluxes with flux reversal occurring at an ambient concentration of nitrogen dioxide of about 10 ppb. This confirms earlier preliminary findings and strengthens the hypothesis that substantial production of nitrous acid can occur on land surfaces from reaction of nitrogen dioxide and water vapor. Detailed measurements of nitrous acid have been made in central urban, suburban, and rural environments. These measurements, in conjunction with a simple box model, indicate that the atmospheric concentrations of nitrous acid are explicable in terms of a small number of basic processes in which the most important are the surface production of nitrous acid from nitrogen dioxide, atmospheric production from the NO-OH reaction and loss of nitrous acid by photolysis and dry deposition. In the suburban atmosphere, concentrations of nitrous acid are strongly correlated with nitrogen dioxide. In the rural atmosphere a different behavior is seen, with much higher nitrous acid to nitrogen dioxide ratios occurring in more polluted air with nitrogen dioxide concentrations in excess of 10 ppb. At lower nitrogen dioxide concentrations, net deposition of nitrous acid at the ground leads to very low concentrations in advected air. The model study indicates that during daytime in the suburban atmosphere, production of HONO from the NO-OH reaction can compete with photolysis giving a HONO concentration of a few tenths of a part per billion. At the highest observed daytime concentrations of HONO, production of OH radical from its photolysis can proceed at a rate more than 10 times faster than from photolysis of ozone.

  2. Renal handling of terephthalic acid

    SciTech Connect

    Tremaine, L.M.; Quebbemann, A.J.

    1985-01-01

    By use of the Sperber in vivo chicken preparation method, infusion of radiolabeled terephthalic acid ((/sup 14/C)TPA) into the renal portal circulation revealed a first-pass excretion of the unchanged compound into the urine. This model was utilized further to characterize the excretory transport of (/sup 14/C)TPA and provide information on the structural specificity in the secretion of dicarboxylic acids. At an infusion rate of 0.4 nmol/min. 60% of the (/sup 14/C)TPA which reached the kidney was directly excreted. An infusion rate of 3 or 6 mumol/min resulted in complete removal of (/sup 14/C)TPA by the kidney. These results indicate that TPA is both actively secreted and actively reabsorbed when infused at 0.4 nmol/min and that active reabsorption is saturated with the infusion of TPA at higher concentrations. The secretory process was saturated with the infusion of TPA at 40 mumol/mn. The excretory transport of TPA was inhibited by the infusion of probenecid, salicylate, and m-hydroxybenzoic acid, indicating that these organic acids share the same organic anion excretory transport process. m-Hydroxybenzoic acid did not alter the simultaneously measured excretory transport of p-aminohippuric acid (PAH), suggesting that there are different systems involved in the secretion of TPA and PAH. The structural specificity for renal secretion of dicarboxylic acids was revealed by the use of o-phthalic acid and m-phthalic acid as possible inhibitors of TPA secretion.

  3. Pediatric poisonings from household products: hydrofluoric acid and methacrylic acid.

    PubMed

    Perry, H E

    2001-04-01

    Household products continue to be a cause of poisoning morbibidity and mortality. Young children frequently are exposed to cleaning products and cosmetics in the course of exploring their environment. Most of these exposures are insignificant, but some result in death or permanent disability. This review discusses two products that have been responsible for serious injury and death in children: hydrofluoric acid and methacrylic acid. It also discusses federal initiatives designed to protect children from these and other household hazards.

  4. Docosahexaenoic acid affects arachidonic acid uptake in megakaryocytes

    SciTech Connect

    Schick, P.K.; Webster, P.

    1987-05-01

    Dietary omega 3 fatty acids are thought to prevent atherosclerosis, possibly by modifying platelet (PT) function and arachidonic acid (20:4) metabolism. The study was designed to determine whether omega 3 fatty acids primarily affect 20:4 metabolism in megakaryocytes (MK), bone marrow precursors of PT, rather than in circulating PT. MK and PT were isolated from guinea pigs and incubated with (/sup 14/C)-20:4 (0.13uM). Docosahexaenoic acid (22:6) is a major omega 3 fatty acid in marine oils. The incubation of MK with 22:6 (0.1, 1.0 uM) resulted in the decrease of incorporation of (/sup 14/C)-20:4 into total MK phospholipids, 16% and 41% respectively. Alpha-linolenic acid (18:3), a major omega 3 fatty acid present in American diets, had no effect on 20:4 uptake in MK. 22:6 primarily affected the uptake of (/sup 14/C)-20:4 into phosphatidylethanolamine (PE) and phosphatidylserine (PS) in MK. In MK, 22:6 (0.1, 1.0 uM) caused a decrease of incorporation of (/sup 14/C)-20:4 into PE, 21% and 55% respectively; a decrease into PS, 16% and 48% respectively; but only a decrease of 4% and 18%, respectively, into phosphatidylcholine; and a decrease of 3% and 21% into phosphatidylinositol 22:6 (3.0 uM) had no effect on the uptake of AA into PT phospholipids. The study shows that 22:6 has a selective effect on AA uptake in MK and that the acylation or transacylation of PE and PS are primarily affected. 22:6 and other marine omega 3 fatty acids appear to primarily affect megakaryocytes which may result in the production of platelets with abnormal content and compartmentalization of AA.

  5. gamma-Carboxyglutamic acid distribution.

    PubMed

    Zytkovicz, T H; Nelsestuen, G L

    1976-09-24

    The distribution of the vitamin K-dependent amino acid, gamma-carboxyglutamic acid was examined in proteins from a variety of sources. Proteins examined include purified rat and bovine coagulation proteins, barium citrate-adsorbing proteins from trout plasma, lamprey plasma, earthworm hemolymph, army worm hemolymph, lobster hemolymph, E. coli B/5, soybean leaf, the protein lysate from the hemolymph cell of the horseshoe crab and parathyroid extract. Other purified proteins examined included human alpha-1-antitrypsin, pepsinogen, S-100, fetuin, tropomyosin-troponin and complement protein C-3. Of these, only the blood-cotting proteins and the vertebrate plasma samples were shown to contain gamma-carboxyglutamic acid.

  6. Abscission: Role of Abscisic Acid

    PubMed Central

    Cracker, L. E.; Abeles, F. B.

    1969-01-01

    The effect of abscisic acid on cotton (Gossypium hirsutum L. cv. Acala 4-42) and bean (Phaseolus vulgaris L. cv. Red Kidney) explants was 2-fold. It increased ethylene production from the explants, which was found to account for some of its ability to accelerate abscission. Absci is acid also increased the activity of cellulase. Increased synthesis of cellulase was not du to an increase in aging of the explants but rather was an effect of abscisic acid on the processes that lead to cellulase synthesis or activity. PMID:16657181

  7. Chemiluminescent measurement of atmospheric acid

    NASA Technical Reports Server (NTRS)

    Stedman, D. H.; Kok, G. L.

    1974-01-01

    The design and construction of a gas phase acid sensitive analyzer are reported. These studies showed that the chemical system was a practical analytical method. A complete instrument was developed and prepared for field testing. A Titan 3-C rocket was scheduled for launching on February 11, 1974. Through preparations made by NASA Langley the instrument was set up to monitor the acid concentration in the rocket exhaust. Due to adverse wind conditions no acid was detected. This entire trip is described in detail.

  8. Be an acid rain detective

    SciTech Connect

    Atwill, L.

    1982-07-01

    Acid rain is discussed in a question and answer format. The article is aimed at educating sport fishermen on the subject, and also to encourage them to write their congressmen, senators, and the President about the acid rain problem. The article also announces the availability of an acid rain test kit available through the magazine, ''Sports Afield.'' The kit consists of pH-test paper that turns different shades of pink and blue according to the pH of the water tested. The color of the test paper is then compared to a color chart furnished in the kit and an approximate pH can be determined.

  9. PRODUCTION OF TRIFLUOROACETIC ACID COMPOUNDS

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-08-30

    A process is described for the preparation of trifluoroacetic acid. Acetone vapor diluted wlth nitrogen and fluorine also diluted with nltrogen are fed separately at a temperature of about 210 deg C into a reaction vessel containing a catalyst mass selected from-the group consisting of silver and gold. The temperature in the reaction vessel is maintained in the range of 200 deg to 250 deg C. The reaction product, trifluoroacetyl fluoride, is absorbed in aqueous alkali solution. Trifluoroacetic acid is recovered from the solution by acidification wlth an acid such as sulfuric followed by steam distillation.

  10. Can crops tolerate acid rain

    SciTech Connect

    Kaplan, J.K.

    1989-11-01

    This brief article describes work by scientists at the ARS Air Quality-Plant Growth and Development Laboratory in Raleigh, North Carolina, that indicates little damage to crops as a result of acid rain. In studies with simulated acid rain and 216 exposed varieties of 18 crops, there were no significant injuries nor was there reduced growth in most species. Results of chronic and acute exposures were correlated in sensitive tomato and soybean plants and in tolerant winter wheat and lettuce plants. These results suggest that 1-hour exposures could be used in the future to screen varieties for sensitivity to acid rain.

  11. Free acidity measurement - a review.

    PubMed

    Srinivasan, T G; Vasudeva Rao, P R

    2014-01-01

    Free acidity is an important parameter especially in the presence of hydrolysable ions. Several methods have been developed for the determination of free acidity, attributing due importance to the accuracy and the precision of the measurement with the aim of the easiness of the methodology as well as post-measurement recovery in mind. This review covers important methods for the determination of free acidity with emphasis on actinide containing solutions, reported in the literature over the past several decades classifying them into different categories.

  12. Amino Acids from a Comet

    NASA Technical Reports Server (NTRS)

    Cook, Jamie Elisla

    2009-01-01

    NASA's Stardust spacecraft returned samples from comet 81P/Wild 2 to Earth in January 2006. Examinations of the organic compounds in cometary samples can reveal information about the prebiotic organic inventory present on the early Earth and within the early Solar System, which may have contributed to the origin of life. Preliminary studies of Stardust material revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds (cometary- vs. terrestrial contamination) could not be identified. We have recently measured the carbon isotopic ratios of these amino acids to determine their origin, leading to the first detection of a coetary amino acid.

  13. 40 CFR 721.10679 - Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester (generic). 721.10679 Section 721... Carboxylic acid, substituted alkylstannylene ester, reaction products with inorganic acid tetra alkyl ester... identified generically as carboxylic acid, substituted alkylstannylene ester, reaction products...

  14. Enhanced acid tolerance of Rhizopus oryzae during fumaric acid production.

    PubMed

    Liu, Ying; Lv, Chunwei; Xu, Qing; Li, Shuang; Huang, He; Ouyang, Pingkai

    2015-02-01

    Ensuring a suitable pH in the culture broth is a major problem in microorganism-assisted industrial fermentation of organic acids. To address this issue, we investigated the physiological changes in Rhizopus oryzae at different extracellular pH levels and attempted to solve the issue of cell shortage under low pH conditions. We compared various parameters, such as membrane fatty acids' composition, intracellular pH, and adenosine triphosphate (ATP) concentration. It was found that the shortage of intracellular ATP might be the main reason for the low rate of fumaric acid production by R. oryzae under low pH conditions. When 1 g/l citrate was added to the culture medium at pH 3.0, the intracellular ATP concentration increased from 0.4 to 0.7 µmol/mg, and the fumaric acid titer was enhanced by 63% compared with the control (pH 3.0 without citrate addition). The final fumaric acid concentration at pH 3.0 reached 21.9 g/l after 96 h of fermentation. This strategy is simple and feasible for industrial fumaric acid production under low pH conditions.

  15. Oleic acid-based gemini surfactants with carboxylic acid headgroups.

    PubMed

    Sakai, Kenichi; Umemoto, Naoki; Matsuda, Wataru; Takamatsu, Yuichiro; Matsumoto, Mutsuyoshi; Sakai, Hideki; Abe, Masahiko

    2011-01-01

    Anionic gemini surfactants with carboxylic acid headgroups have been synthesized from oleic acid. The hydrocarbon chain is covalently bound to the terminal carbonyl group of oleic acid via an ester bond, and the carboxylic acid headgroups are introduced to the cis double bond of oleic acid via disuccinyl units. The surfactants exhibit pH-dependent protonation-deprotonation behavior in aqueous solutions. In alkaline solutions (pH 9 in the presence of 10 mmol dm(-3) NaCl as the background electrolyte), the surfactants can lower the surface tension as well as form molecular assemblies, even in the region of low surfactant concentrations. Under acidic (pH 3) or neutral (pH 6-7) conditions, the surfactants are intrinsically insoluble in aqueous media and form a monolayer at the air/water interface. In this study, we have investigated physicochemical properties such as the function of the hydrocarbon chain length by means of static surface tension, pyrene fluorescence, dynamic light scattering, surface pressure-area isotherms, and infrared external reflection measurements.

  16. In situ gels improve formation acidizing

    SciTech Connect

    Yeager, V.; Shuchart, C.

    1997-01-20

    Viscosity-controlled acid effectively improves acid placement, provides more uniform damage removal, improves surface etching, and controls acid fluid loss. Viscosity-controlled acid (VCA) contains gels that break back to original viscosity 1 day after being pumped. These acids have been used for: matrix-acidizing long horizontal and vertical well intervals; controlling fluid loss in fracture acidizing to obtain longer fractures and deeper live-acid penetration. Fluid pH controls gel formation and breaking. In one operator`s horizontal wells, viscosity-controlled acid increased production by 2.5--6 fold. In carbonate formation fracture-acidizing, these acids have shown production improvements of 170 to 375%. VCA acid can be used in both cased or open hole, in vertical or deviated/horizontal wells.

  17. Acid preservation systems for food products

    SciTech Connect

    Tiberio, J. E.; Cirigiano, M. C.

    1984-10-16

    Fumaric acid is used in combination with critical amounts of acetic acid to preserve acid containing food products from microbiological spoilage in the absence of or at reduced levels of chemical preservative.

  18. Treatment of Amino Acid Metabolism Disorders

    MedlinePlus

    ... amino acid metabolism disorders Treatment of amino acid metabolism disorders E-mail to a friend Please fill ... This is an amino acid that helps remove ammonia from the blood. Babies with HCY may need ...

  19. Treatment of Fatty Acid Oxidation Disorders

    MedlinePlus

    ... of fatty acid oxidation disorders Treatment of fatty acid oxidation disorders E-mail to a friend Please ... page It's been added to your dashboard . Fatty acid oxidation disorders are rare health conditions that affect ...

  20. Genetics Home Reference: sialic acid storage disease

    MedlinePlus

    ... Home Health Conditions sialic acid storage disease sialic acid storage disease Enable Javascript to view the expand/ ... Download PDF Open All Close All Description Sialic acid storage disease is an inherited disorder that primarily ...

  1. Genetics Home Reference: lysosomal acid lipase deficiency

    MedlinePlus

    ... Home Health Conditions lysosomal acid lipase deficiency lysosomal acid lipase deficiency Enable Javascript to view the expand/ ... Download PDF Open All Close All Description Lysosomal acid lipase deficiency is an inherited condition characterized by ...

  2. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

    1995-09-12

    An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 10 figs.

  3. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E. Philip; Alexandratos, Spiro D.; Gatrone, Ralph C.; Chiarizia, Ronato

    1995-01-01

    An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

  4. Bile acid sequestrants for cholesterol

    MedlinePlus

    ... ency/patientinstructions/000787.htm Bile acid sequestrants for cholesterol To use the sharing features on this page, ... are medicines that help lower your LDL (bad) cholesterol . Too much cholesterol in your blood can stick ...

  5. Low acid producing solid propellants

    NASA Technical Reports Server (NTRS)

    Bennett, Robert R.

    1995-01-01

    The potential environmental effects of the exhaust products of conventional rocket propellants have been assessed by various groups. Areas of concern have included stratospheric ozone, acid rain, toxicity, air quality and global warming. Some of the studies which have been performed on this subject have concluded that while the impacts of rocket use are extremely small, there are propellant development options which have the potential to reduce those impacts even further. This paper discusses the various solid propellant options which have been proposed as being more environmentally benign than current systems by reducing HCI emissions. These options include acid neutralized, acid scavenged, and nonchlorine propellants. An assessment of the acid reducing potential and the viability of each of these options is made, based on current information. Such an assessment is needed in order to judge whether the potential improvements justify the expenditures of developing the new propellant systems.

  6. Abiotic synthesis of fatty acids

    NASA Technical Reports Server (NTRS)

    Leach, W. W.; Nooner, D. W.; Oro, J.

    1978-01-01

    The formation of fatty acids by Fischer-Tropsch-type synthesis was investigated with ferric oxide, ammonium carbonate, potassium carbonate, powdered Pueblito de Allende carbonaceous chondrite, and filings from the Canyon Diablo meteorite used as catalysts. Products were separated and identified by gas chromatography and mass spectrometry. Iron oxide, Pueblito de Allende chondrite, and Canyon Diablo filings in an oxidized catalyst form yielded no fatty acids. Canyon Diablo filings heated overnight at 500 C while undergoing slow purging by deuterium produced fatty acids only when potassium carbonate was admixed; potassium carbonate alone also produced these compounds. The active catalytic combinations gave relatively high yields of aliphatic and aromatic hydrocarbons; substantial amounts of n-alkenes were almost invariably observed when fatty acids were produced; the latter were in the range C6 to C18, with maximum yield in C9 or 10.

  7. Compact oleic acid in HAMLET.

    PubMed

    Fast, Jonas; Mossberg, Ann-Kristin; Nilsson, Hanna; Svanborg, Catharina; Akke, Mikael; Linse, Sara

    2005-11-07

    HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a complex between alpha-lactalbumin and oleic acid that induces apoptosis in tumor cells, but not in healthy cells. Heteronuclear nuclear magnetic resonance (NMR) spectroscopy was used to determine the structure of 13C-oleic acid in HAMLET, and to study the 15N-labeled protein. Nuclear Overhauser enhancement spectroscopy shows that the two ends of the fatty acid are in close proximity and close to the double bond, indicating that the oleic acid is bound to HAMLET in a compact conformation. The data further show that HAMLET is a partly unfolded/molten globule-like complex under physiological conditions.

  8. Biopreservation by lactic acid bacteria.

    PubMed

    Stiles, M E

    1996-10-01

    Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Lactic acid bacteria have a major potential for use in biopreservation because they are safe to consume and during storage they naturally dominate the microflora of many foods. In milk, brined vegetables, many cereal products and meats with added carbohydrate, the growth of lactic acid bacteria produces a new food product. In raw meats and fish that are chill stored under vacuum or in an environment with elevated carbon dioxide concentration, the lactic acid bacteria become the dominant population and preserve the meat with a "hidden' fermentation. The same applies to processed meats provided that the lactic acid bacteria survive the heat treatment or they are inoculated onto the product after heat treatment. This paper reviews the current status and potential for controlled biopreservation of foods.

  9. Biotechnological production of citric acid

    PubMed Central

    Max, Belén; Salgado, José Manuel; Rodríguez, Noelia; Cortés, Sandra; Converti, Attilio; Domínguez, José Manuel

    2010-01-01

    This work provides a review about the biotechnological production of citric acid starting from the physicochemical properties and industrial applications, mainly in the food and pharmaceutical sectors. Several factors affecting citric acid fermentation are discussed, including carbon source, nitrogen and phosphate limitations, pH of culture medium, aeration, trace elements and morphology of the fungus. Special attention is paid to the fundamentals of biochemistry and accumulation of citric acid. Technologies employed at industrial scale such as surface or submerged cultures, mainly employing Aspergillus niger, and processes carried out with Yarrowia lipolytica, as well as the technology for recovering the product are also described. Finally, this review summarizes the use of orange peels and other by-products as feedstocks for the bioproduction of citric acid. PMID:24031566

  10. Nucleic acid arrays and methods of synthesis

    DOEpatents

    Sabanayagam, Chandran R.; Sano, Takeshi; Misasi, John; Hatch, Anson; Cantor, Charles

    2001-01-01

    The present invention generally relates to high density nucleic acid arrays and methods of synthesizing nucleic acid sequences on a solid surface. Specifically, the present invention contemplates the use of stabilized nucleic acid primer sequences immobilized on solid surfaces, and circular nucleic acid sequence templates combined with the use of isothermal rolling circle amplification to thereby increase nucleic acid sequence concentrations in a sample or on an array of nucleic acid sequences.

  11. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  12. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...

  13. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  14. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...

  15. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...

  16. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  17. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Succinic acid. 184.1091 Section 184.1091 Food and....1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It is commercially prepared...

  18. 21 CFR 184.1091 - Succinic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Succinic acid. 184.1091 Section 184.1091 Food and... Substances Affirmed as GRAS § 184.1091 Succinic acid. (a) Succinic acid (C4H6O4, CAS Reg. No. 110-15-6), also referred to as amber acid and ethylenesuccinic acid, is the chemical 1,4-butanedioic acid. It...

  19. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Adipic acid. 184.1009 Section 184.1009 Food and....1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid oxidation of cyclohexanol...

  20. 21 CFR 184.1009 - Adipic acid.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Adipic acid. 184.1009 Section 184.1009 Food and... Substances Affirmed as GRAS § 184.1009 Adipic acid. (a) Adipic acid (C6H10O4, CAS Reg. No. 00124-04-9) is also known as 1,4-butanedicarboxylic acid or hexane-dioic acid. It is prepared by nitric acid...