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Sample records for telluric acid transformations

  1. Purification of telluric acid for SNO+ neutrinoless double-beta decay search

    NASA Astrophysics Data System (ADS)

    Hans, S.; Rosero, R.; Hu, L.; Chkvorets, O.; Chan, W. T.; Guan, S.; Beriguete, W.; Wright, A.; Ford, R.; Chen, M. C.; Biller, S.; Yeh, M.

    2015-09-01

    Tellurium-130 has the highest natural abundance of any double-beta decay isotopes. Recently it has been developed as a promising candidate for loading in liquid scintillator to explore the Majorana or Dirac nature of the neutrino through a search for neutrinoless double beta decay (0νββ). To this end, procedures have been developed to transfer tellurium ions into the organic liquid by a water-based loading technology. However, traces of naturally occurring radioactivity and cosmic-ray induced isotopes introduced into the scintillator with tellurium could produce undesirable contaminations in the 130Te 0νββ region. Measurements using various elemental spikes prepared from different chemical forms indicate that the uses of self-scavenging as well as acid and thermal recrystallization prior to the preparation of a tellurium-loaded liquid scintillator can deplete U and Th and several cosmic-activated isotopes from Te feedstock by a factor of 102-103 in a single pass. The process is also found to improve the optical transmission in the blue region, sensible to the photomultiplier tube, by removing traces of colored impurities. In addition to the scintillator-based experiments, this cleansing scheme has potential applications to the production of radiopure tellurium crystals for other rare-event experiments.

  2. Telluric currents in pipelines

    NASA Astrophysics Data System (ADS)

    Trichtchenko, L.

    2004-05-01

    Inductive coupling of the varying geomagnetic field to pipelines produce low-frequency ac-currents which can affect their operation. The presented approach to the mathematical modeling of the geomagnetically induced (telluric) currents in pipelines was as follows. First is to evaluate the induction effect in general. This has been done by application of Maxwell's equations to model induction in the infinitely long multi-layered cylinder under plane electromagnetic wave excitation. Important results were obtained by calculating the transfer function relating the total electric current in the steel to the non-disturbed (in the absence of the cylinder) electric field. It is shown that this function depends on the frequency as well as on the electromagnetic properties and sizes of the multilayered cylinder. However, it is constant for most of the geomagnetic frequency range (0.01 mHz to 80 mHz) and the typical values of the pipeline electromagnetic properties and size. Hence, for the geomagnetic frequency range one can expect that when the non-disturbed electric field in time-domain is known, induced currents can be calculated in the time-domain by applying a constant scaling factor. Next step is to provide the non-disturbed electric field. Using the same plane wave assumption and layered earth conductivity model, the geomagnetic field was converted to the geoelectric field. The frequency response here shows more power at high frequencies and cannot be approximated by a constant. The last step in the evaluation of the modeling is comparison with pipe-to-soil potential variations (PSP)produced by telluric currents on a few pipelines. Comparisons show that linear correlation coefficients vary from 0.6 to 0.9, depending on the distance from the pipeline recording site to location of the geomagnetic observatory. These correlations confirm the similarity of the frequency content of PSP fluctuations to the electric field variations. For the modeling of the amplitude changes in PSP along the pipeline, distributed source transmission line model can be applied with a spatially non-uniform electric field as an input. The non-uniform electric field can be found by further detailed 2-d modeling of the earth ground conductivity along the pipeline route, which is the subject of further investigations.

  3. Structural evolution in iron tellurates

    SciTech Connect

    Lee, A. van der Astier, R.

    2007-04-15

    Three new members within the iron tellurate family have been synthesized and characterized by single-crystal diffraction. Fe{sub 2}Te{sub 3}O{sub 9} is orthorhombic, a=7.80240(10)A, b=17.7501(3)A, c=5.28050(10)A, Z=4, space group Pnma, final agreement factors R{sub 1}=0.0261(wR{sub 2}=0.0688) for 1271 independent reflections. Fe{sub 3}Te{sub 4}O{sub 12} is monoclinic, a=9.1312(2)A, b=7.3554(2)A, c=15.7379(3)A, {beta}=107.950(10){sup o}, Z=4, space group P2{sub 1}/c, final agreement factors R{sub 1}=0.0380(wR{sub 2}=0.0281) for 3302 independent reflections. FeTe{sub 6}O{sub 13} is trigonal, a=b=10.16630(10)A, c=18.9330(3)A, Z=6, space group R3-barm, final agreement factors R{sub 1}=0.0309(wR{sub 2}=0.0641) for 1264 independent reflections. Together with the four already known members of the family, Fe{sub 2}TeO{sub 5}, Fe{sub 2}TeO{sub 6}, and Fe{sub 2}Te{sub 3}O{sub 9} (a dimorphic variant of the afore-mentioned structure with the same chemical formula), and Fe{sub 2}Te{sub 4}O{sub 11}, the iron tellurates now span from relatively Fe-rich and Te-poor to relatively Fe-poor to Te-rich compounds. The structural diversity within Fe-Te-O system is discussed in terms of the lone-pair stereochemistry of the Te{sup 4+} anion and the cross-over from Fe{sup 3+} to mixed-valence Fe{sup 3+}/Fe{sup 2+} and Fe{sup 2+} coordination polyhedra compounds.

  4. Transformations of alkoxysilanes in fluorosulfonic acid

    SciTech Connect

    Kudasheva, I.A.; Musarinov, R.S.; Nedogrei, E.P.; Akhmatdinov, R.T.; Kantor, E.A.; Rakhmankulov, D.L.

    1986-09-10

    By the NMR investigation of the behavior of mono-, di-, and trialkoxysilanes in fluorosulphonic acid at -70 to +20/sup 0/C it was established that in this medium siliconium, alkoxy-, and dialkoxysiliconium ions do not form. Transformations of the above compounds depend on the number of alkoxy groups. Monoalkoxytrimethysilanes and hexamethyldisiloxane are stable in fluorosulfonic acid up to -30/sup 0/C. At this temperature they transform into trimethylfluorosilane which is stable in this medium up to +10/sup 0/C. At higher temperatures trimethylfluorosilane transforms into dimethyldifluorosilane. Dimethyldialkoxysilanes at -70/sup 0/C in fluorosulfonic acid transform into dimethyldi-(fluorosulfoxy)silane which at -40/sup 0/C transforms into dimethyldifluorosilane. Methyltrialkoxysilanes at -70/sup 0/, and methylphenyldialkoxysilanes at -40/sup 0/C in fluorosulfonic acid transform into methyltrifluorosilane.

  5. Genetic Evidence for a Molybdopterin-Containing Tellurate Reductase

    PubMed Central

    Theisen, Joanne; Zylstra, Gerben J.

    2013-01-01

    The genetic identity and cofactor composition of the bacterial tellurate reductase are currently unknown. In this study, we examined the requirement of molybdopterin biosynthesis and molybdate transporter genes for tellurate reduction in Escherichia coli K-12. The results show that mutants deleted of the moaA, moaB, moaE, or mog gene in the molybdopterin biosynthesis pathway lost the ability to reduce tellurate. Deletion of the modB or modC gene in the molybdate transport pathway also resulted in complete loss of tellurate reduction activity. Genetic complementation by the wild-type sequences restored tellurate reduction activity in the mutant strains. These findings provide genetic evidence that tellurate reduction in E. coli involves a molybdoenzyme. PMID:23475618

  6. Trans Alaska Pipeline - potential measurements and telluric current

    SciTech Connect

    Smart, A.L.

    1982-09-01

    Construction and operation of the Trans Alaska Pipeline System (TAPS) has always required solving problems unique to the arctic environment with corrosion control being no exception. Aurorally induced telluric current causes fluctuation of the pipe-to-soil potential measurements which are normally monitored to indicate satisfactory operation of a corrosion control system. This condition can, at times, so obscure these potentials that they are meaningless without correlating data on the telluric activity. A technique has been developed for potential surveys which provides the necessary telluric current correlation. The TAPS protection system and its interaction with telluric current are discussed. A chronology of the technique development is included.

  7. Mineralogical transformations controlling acid mine drainage chemistry

    SciTech Connect

    Peretyazhko, Tetyana; Zachara, John M.; Boily, Jean F.; Xia, Yuanxian; Gassman, Paul L.; Arey, Bruce W.; Burgos, William D.

    2009-05-30

    The role of Fe(III) minerals in controlling acid mine drainage (AMD) chemistry was studied using samples from two AMD sites [Gum Boot (GB) and Fridays-2 (FR)] located in northern Pennsylvania. Chemical extractions, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to identify and characterize Fe(III) phases. The mineralogical analysis revealed that schwertmannite and goethite were the principal Fe(III) phases in the sediments. Schwertmannite transformation occurred at the GB site where poorly-crystallized goethite rich in surface-bound sulfate was initially formed. In contrast, no schwertmannite transformation occurred at the FR site. The goethite in GB sediments had spherical morphology due to preservation of schwertmannite structure by adsorbed sulfate. Results of chemical extractions showed that poorly-crystallized goethite was subject to further crystallization accompanied by sulfate desorption. Changes in sulfate speciation preceded its desorption, with a conversion of bidentate- to monodentate-bound sulfate surface complexes. Laboratory sediment incubation experiments were conducted to evaluate the effect of mineral transformation on water chemistry. Incubation experiments were carried out with schwertmannite-containing sediments and AMD waters with different pH and chemical composition. The pH decreased to 1.9-2.2 in all suspensions and the concentrations of dissolved Fe and S increased significantly. Regardless of differences in the initial water composition, pH, Fe and S were similar in suspensions of the same sediment. XRD measurements revealed that schwertmannite transformed into goethite in GB and FR sediments during laboratory incubation. The incubation experiment demonstrated that schwertmannite transformation controlled AMD water chemistry during “closed system” laboratory contact.

  8. EMT - Empirical-mode-decomposition-based Magneto-Telluric Processing

    NASA Astrophysics Data System (ADS)

    Neukirch, M.; Garcia, X.

    2012-04-01

    We present a new Magneto-Telluric (MT) data processing scheme based on an emerging non linear, non stationary time series analysis tool, called the Empirical Mode Decomposition (EMD) or Hilbert-Huang Transform (HHT), to transform data into a non-stationary frequency domain and a robust principal component regression to estimate the most likely MT transfer functions from the data with the 2-σ confidence intervals computed by a bootstrap algorithm. Optionally, data quality can be controlled by a physical coherence and a signal power filter. MT sources are assumed to be quasi stationary and therefore a (windowed) Fourier Transform is often applied to transform the time series into the frequency domain in which Transfer Functions (TF) are defined between the electromagnetic field components. This assumption can break down in the presence of noise or when the sources are non stationary, and then TF estimates can become unreliable when obtained through a stationary transform like the Fourier transform. Our TF estimation scheme naturally deals with non stationarity without introducing artifacts and, therefore, potentially can distinguish quasi-stationary sources and non-stationary noise. In contrast to previous works on using HHT for MT processing, we argue the necessity of a multivariate EMD to model the MT problem physically correctly and highlight the resulting possibility to use instantaneous parameters as independent and identically distributed variables. Furthermore, we define a homogenization between data channels of frequency discrepancies due to non stationarity and noise. The TF estimation in the frequency domain bases on a robust principal component analysis in order to find two source polarizations. These two principal components are used as predictor to regress robustly the data channels within a bootstrap algorithm to estimate the Earth's Transfer function with 2-σ confidence interval supplied by the measured data.The scheme can be used with and without aid by any number of remote reference stations. The performance of this scheme will be demonstrated on MT data and compared with BIRRP, a widely used MT processing software by Alan Chave.

  9. Telluric currents: A meeting of theory and observation

    SciTech Connect

    Boteler, D.H.; Seager, W.H.

    1998-09-01

    Pipe-to-soil (P/S) potential variations resulting from telluric currents have been observed on pipelines in many locations. However, it has never teen clear which parts of a pipeline will experience the worst effects. Two studies were conducted to answer this question. Distributed-source transmission line (DSTL) theory was applied to the problem of modeling geomagnetic induction in pipelines. This theory predicted that the largest P/S potential variations would occur at the ends of the pipeline. The theory also predicted that large P/S potential variations, of opposite sign, should occur on either side of an insulating flange. Independently, an observation program was conducted to determine the change in telluric current P/S potential variations and to design counteractive measures along a pipeline in northern Canada. Observations showed that the amplitude of P/S potential fluctuations had maxima at the northern and southern ends of the pipeline. A further set of recordings around an insulating flange showed large P/S potential variations, of opposite sign, on either side of the flange. Agreement between the observations and theoretical predictions was remarkable. While the observations confirmed the theory, the theory explains how P/S potential variations are produced by telluric currents and provides the basis for design of cathodic protection systems for pipelines that can counteract any adverse telluric effects.

  10. Precise Modelling of Telluric Features in Astronomical Spectra

    NASA Astrophysics Data System (ADS)

    Seifahrt, A.; Käufl, H. U.; Zängl, G.; Bean, J.; Richter, M.; Siebenmorgen, R.

    2010-12-01

    Ground-based astronomical observations suffer from the disturbing effects of the Earth's atmosphere. Oxygen, water vapour and a number of atmospheric trace gases absorb and emit light at discrete frequencies, shaping observing bands in the near- and mid-infrared and leaving their fingerprints - telluric absorption and emission lines - in astronomical spectra. The standard approach of removing the absorption lines is to observe a telluric standard star: a time-consuming and often imperfect solution. Alternatively, the spectral features of the Earth's atmosphere can be modelled using a radiative transfer code, often delivering a satisfying solution that removes these features without additional observations. In addition the model also provides a precise wavelength solution and an instrumental profile.

  11. The role of telluric and magnetotelluric methods in hydrocarbon investigation

    SciTech Connect

    Csoergei, J.; Nemesi, I.; Papa, A.; Varga, G. )

    1993-09-01

    One of the basic tasks of hydrocarbon prospecting is to investigate the morphology and internal structure of the basement underlying the sediments. Gravity is applied world wide to solve this task; the depth to the basement, however, cannot always be determined. With increasing depth in basins of 3-8 km depth, basement structures are poorly reflected; anticorrelation was found in some cases. Telluric and magnetotelluric apply a natural electromagnetic field around the Earth. This field shows variations in a very wide frequency range. Electromagnetic waves of different frequencies can penetrate into different depths, providing information o the internal structure of the Earth. A survey begins with a limited number of magnetotelluric measurements to learn the basic geologic model and to tune up the frequency range, which provides data about the depth interval we are interested in. In the second stage, telluric measurements are done in a dense grid (1-2 km station spacing), using the frequencies where penetration depth exceeds the depth to the basement. In the third stage, magnetotelluric soundings are performed on the telluric anomalies. When interpreting these soundings, we can decided whether the anomalies are caused by changes in the depth to the basement or by changes in the resistivity of the overlying sedimentary sequences. As a result, resistivity maps of the sediments and basement depth maps can be constructed. Both maps are useful in finding potential hydrocarbon traps and can be used to design a cost-effective detailed seismic survey. The case histories presented in this paper are from the Carpathian basin in Hungary.

  12. Unique roles of acidic amino acids in phase transformation of calcium phosphates.

    PubMed

    Chu, Xiaobin; Jiang, Wenge; Zhang, Zhisen; Yan, Yang; Pan, Haihua; Xu, Xurong; Tang, Ruikang

    2011-02-10

    Although phase transformation is suggested as a key step in biomineralization, the chemical scenario about how organic molecules mediate inorganic phase transformations is still unclear. The inhibitory effect of amino acids on hydroxyapatite (HAP, the main inorganic component of biological hard tissues such as bone and enamel) formation was concluded by the previous biomimetic modeling based upon direct solution crystallization. Here we demonstrate that acidic amino acids, Asp and Glu, could promote HAP crystallization from its precursor crystal, brushite (DCPD). However, such a promotion effect could not be observed when the nonacidic amino acids were applied in the transformation-based HAP formation. We found that the specific modification of acidic amino acid on crystal-solution interfaces played a key role in the phase transition. The distinct properties between DCPD and HAP in the solution resulted in an interfacial energy barrier to suppress the spontaneous formation of HAP phase on DCPD phase. Different from the other amino acids, the carboxylate-rich amino acids, Asp and Glu, could modify the interfacial characteristics of these two calcium phosphate crystals to make them similar to each other. The experiments confirmed that the involvement of Asp or Glu reduced the interfacial energy barrier between DCPD and HAP, leading to a trigger effect on the phase transformation. An in-depth understanding about the unique roles of acidic amino acids may contribute to understanding phase transformation controls druing biomineralization. PMID:21190387

  13. Correcting for telluric absorption: Methods, case studies, and release of the TelFit code

    SciTech Connect

    Gullikson, Kevin; Kraus, Adam; Dodson-Robinson, Sarah

    2014-09-01

    Ground-based astronomical spectra are contaminated by the Earth's atmosphere to varying degrees in all spectral regions. We present a Python code that can accurately fit a model to the telluric absorption spectrum present in astronomical data, with residuals of ∼3%-5% of the continuum for moderately strong lines. We demonstrate the quality of the correction by fitting the telluric spectrum in a nearly featureless A0V star, HIP 20264, as well as to a series of dwarf M star spectra near the 819 nm sodium doublet. We directly compare the results to an empirical telluric correction of HIP 20264 and find that our model-fitting procedure is at least as good and sometimes more accurate. The telluric correction code, which we make freely available to the astronomical community, can be used as a replacement for telluric standard star observations for many purposes.

  14. Conjugated Linoleic Acid Accumulation via 10-Hydroxy-12-Octadecaenoic Acid during Microaerobic Transformation of Linoleic Acid by Lactobacillus acidophilus

    PubMed Central

    Ogawa, Jun; Matsumura, Kenji; Kishino, Shigenobu; Omura, Yoriko; Shimizu, Sakayu

    2001-01-01

    Specific isomers of conjugated linoleic acid (CLA), a fatty acid with potentially beneficial physiological and anticarcinogenic effects, were efficiently produced from linoleic acid by washed cells of Lactobacillus acidophilus AKU 1137 under microaerobic conditions, and the metabolic pathway of CLA production from linoleic acid is explained for the first time. The CLA isomers produced were identified as cis-9, trans-11- or trans-9, cis-11-octadecadienoic acid and trans-9, trans-11-octadecadienoic acid. Preceding the production of CLA, hydroxy fatty acids identified as 10-hydroxy-cis-12-octadecaenoic acid and 10-hydroxy-trans-12-octadecaenoic acid had accumulated. The isolated 10-hydroxy-cis-12-octadecaenoic acid was transformed into CLA during incubation with washed cells of L. acidophilus, suggesting that this hydroxy fatty acid is one of the intermediates of CLA production from linoleic acid. The washed cells of L. acidophilus producing high levels of CLA were obtained by cultivation in a medium containing linoleic acid, indicating that the enzyme system for CLA production is induced by linoleic acid. After 4 days of reaction with these washed cells, more than 95% of the added linoleic acid (5 mg/ml) was transformed into CLA, and the CLA content in total fatty acids recovered exceeded 80% (wt/wt). Almost all of the CLA produced was in the cells or was associated with the cells as free fatty acid. PMID:11229917

  15. Surface reactions of iron - enriched smectites: adsorption and transformation of hydroxy fatty acids and phenolic acids

    NASA Astrophysics Data System (ADS)

    Polubesova, Tamara; Olshansky, Yaniv; Eldad, Shay; Chefetz, Benny

    2014-05-01

    Iron-enriched smectites play an important role in adsorption and transformation of soil organic components. Soil organo-clay complexes, and in particular humin contain hydroxy fatty acids, which are derived from plant biopolymer cutin. Phenolic acids belong to another major group of organic acids detected in soil. They participate in various soil processes, and are of concern due to their allelopathic activity. We studied the reactivity of iron-enriched smectites (Fe(III)-montmorillonite and nontronite) toward both groups of acids. We used fatty acids- 9(10),16-dihydroxypalmitic acid (diHPA), isolated from curtin, and 9,10,16-trihydroxypalmitic acid (triHPA); the following phenolic acids were used: ferulic, p-coumaric, syringic, and vanillic. Adsorption of both groups of acids was measured. The FTIR spectra of fatty acid-mineral complexes indicated inner-sphere complexation of fatty acids with iron-enriched smectites (versus outer-sphere complexation with Ca(II)-montmorillonite). The LC-MS results demonstrated enhanced esterification of fatty acids on the iron-enriched smectite surfaces (as compared to Ca(II)-montmorillonite). This study suggests that fatty acids can be esterified on the iron-enriched smectite surfaces, which results in the formation of stable organo-mineral complexes. These complexes may serve as a model for the study of natural soil organo-clay complexes and humin. The reaction of phenolic acids with Fe(III)-montmorillonite demonstrated their oxidative transformation by the mineral surfaces, which was affected by molecular structure of acids. The following order of their transformation was obtained: ferulic >syringic >p-coumaric >vanillic. The LC-MS analysis demonstrated the presence of dimers, trimers, and tetramers of ferulic acid on the surface of Fe(III)-montmorillonite. Oxidation and transformation of ferulic acid were more intense on the surface of Fe(III)-montmorillonite as compared to Fe(III) in solution due to stronger complexation on the Fe(III)-motnomrillonite surface. Our study demonstrate the importance of iron-enriched minerals for the abiotic formation of humic materials and for the transformation of aromatic (phenolic) pollutants.

  16. Deoxycholic acid transformations catalyzed by selected filamentous fungi.

    PubMed

    Kollerov, V V; Lobastova, T G; Monti, D; Deshcherevskaya, N O; Ferrandi, E E; Fronza, G; Riva, S; Donova, M V

    2016-03-01

    More than 100 filamentous fungi strains, mostly ascomycetes and zygomycetes from different phyla, were screened for the ability to convert deoxycholic acid (DCA) to valuable bile acid derivatives. Along with 11 molds which fully degraded DCA, several strains were revealed capable of producing cholic acid, ursocholic acid, 12-keto-lithocholic acid (12-keto-LCA), 3-keto-DCA, 15?-hydroxy-DCA and 15?-hydroxy-12-oxo-LCA as major products from DCA. The last metabolite was found to be a new compound. The ability to catalyze the introduction of a hydroxyl group at the 7(?/?)-positions of the DCA molecule was shown for 32 strains with the highest 7?-hydroxylase activity level for Fusarium merismoides VKM F-2310. Curvularia lunata VKM F-644 exhibited 12?-hydroxysteroid dehydrogenase activity and formed 12-keto-LCA from DCA. Acremonium rutilum VKM F-2853 and Neurospora crassa VKM F-875 produced 15?-hydroxy-DCA and 15?-hydroxy-12-oxo-LCA, respectively, as major products from DCA, as confirmed by MS and NMR analyses. For most of the positive strains, the described DCA-transforming activity was unreported to date. The presented results expand the knowledge on bile acid metabolism by filamentous fungi, and might be suitable for preparative-scale exploitation aimed at the production of marketed bile acids. PMID:26718089

  17. Microbial Transformation of Esters of Chlorinated Carboxylic Acids

    PubMed Central

    Paris, D. F.; Wolfe, N. L.; Steen, W. C.

    1984-01-01

    Two groups of compounds were selected for microbial transformation studies. In the first group were carboxylic acid esters having a fixed aromatic moiety and an increasing length of the alkyl component. Ethyl esters of chlorine-substituted carboxylic acids were in the second group. Microorganisms from environmental waters and a pure culture of Pseudomonas putida U were used. The bacterial populations were monitored by plate counts, and disappearance of the parent compound was followed by gas-liquid chromatography as a function of time. The products of microbial hydrolysis were the respective carboxylic acids. Octanol-water partition coefficients (Kow) for the compounds were measured. These values spanned three orders of magnitude, whereas microbial transformation rate constants (kb) varied only 50-fold. The microbial rate constants of the carboxylic acid esters with a fixed aromatic moiety increased with an increasing length of alkyl substituents. The regression coefficient for the linear relationships between log kb and log Kow was high for group 1 compounds, indicating that these parameters correlated well. The regression coefficient for the linear relationships for group 2 compounds, however, was low, indicating that these parameters correlated poorly. PMID:16346459

  18. Formation of Semimetallic Cobalt Telluride Nanotube Film via Anion Exchange Tellurization Strategy in Aqueous Solution for Electrocatalytic Applications.

    PubMed

    Patil, Supriya A; Kim, Eun-Kyung; Shrestha, Nabeen K; Chang, Jinho; Lee, Joong Kee; Han, Sung-Hwan

    2015-11-25

    Metal telluride nanostructures have demonstrated several potential applications particularly in harvesting and storing green energy. Metal tellurides are synthesized by tellurization process performed basically at high temperature in reducing gas atmosphere, which makes the process expensive and complicated. The development of a facile and economical process for desirable metal telluride nanostructures without complicated manipulation is still a challenge. In an effort to develop an alternative strategy of tellurization, herein we report a thin film formation of self-standing cobalt telluride nanotubes on various conducting and nonconducting substrates using a simple binder-free synthetic strategy based on anion exchange transformation from a thin film of cobalt hydroxycarbonate nanostructures in aqueous solution at room temperature. The nanostructured films before and after ion exchange transformation reaction are characterized using field emission scanning electron microscope, energy dispersive X-ray analyzer, X-ray photoelectron spectroscopy, thin film X-ray diffraction technique, high resolution transmission electron microscope, and selected area electron diffraction analysis technique. After the ion exchange transformation of nanostructures, the film shows conversion from insulator to highly electrical conductive semimetallic characteristic. When used as a counter electrode in I3(-)/I(-) redox electrolyte based dye-sensitized solar cells, the telluride film exhibits an electrocatalytic reduction activity for I3(-) with a demonstration of solar-light to electrical power conversion efficiency of 8.10%, which is highly competitive to the efficiency of 8.20% exhibited by a benchmarked Pt-film counter electrode. On the other hand, the telluride film electrode also demonstrates electrocatalytic activity for oxygen evolution reaction from oxidation of water. PMID:26524092

  19. Transformation of acidic poorly water soluble drugs into ionic liquids.

    PubMed

    Balk, Anja; Wiest, Johannes; Widmer, Toni; Galli, Bruno; Holzgrabe, Ulrike; Meinel, Lorenz

    2015-08-01

    Poor water solubility of active pharmaceutical ingredients (API) is a major challenge in drug development impairing bioavailability and therapeutic benefit. This study is addressing the possibility to tailor pharmaceutical and physical properties of APIs by transforming these into tetrabutylphosphonium (TBP) salts, including the generation of ionic liquids (IL). Therefore, poorly water soluble acidic APIs (Diclofenac, Ibuprofen, Ketoprofen, Naproxen, Sulfadiazine, Sulfamethoxazole, and Tolbutamide) were converted into TBP ILs or low melting salts and compared to the corresponding sodium salts. Free acids and TBP salts were characterized by NMR and IR spectroscopy, DSC and XRPD, DVS and dissolution rate measurements, release profiles, and saturation concentration measurements. TBP salts had lower melting points and glass transition temperatures and dissolution rates were improved up to a factor of 1000 as compared to the corresponding free acid. An increase in dissolution rates was at the expense of increased hygroscopicity. In conclusion, the creation of TBP ionic liquids or solid salts from APIs is a valuable concept addressing dissolution and solubility challenges of poorly water soluble acidic compounds. The data suggested that tailor-made counterions may substantially expand the formulation scientist's armamentarium to meet challenges of poorly water soluble drugs. PMID:25976317

  20. Iron Transformations Induced by an Acid-Tolerant Desulfosporosinus Species

    PubMed Central

    Bertel, Doug; Peck, John; Quick, Thomas J.

    2012-01-01

    The mineralogical transformations of Fe phases induced by an acid-tolerant, Fe(III)- and sulfate-reducing bacterium, Desulfosporosinus sp. strain GBSRB4.2 were evaluated under geochemical conditions associated with acid mine drainage-impacted systems (i.e., low pH and high Fe concentrations). X-ray powder diffractometry coupled with magnetic analysis by first-order reversal curve diagrams were used to evaluate mineral phases produced by GBSRB4.2 in media containing different ratios of Fe(II) and Fe(III). In medium containing Fe predominately in the +II oxidation state, ferrimagnetic, single-domain greigite (Fe3S4) was formed, but the addition of Fe(III) inhibited greigite formation. In media that contained abundant Fe(III) [as schwertmannite; Fe8O8(OH)6SO4 nH2O], the activities of strain GBSRB4.2 enhanced the transformation of schwertmannite to goethite (?-FeOOH), due to the increased pH and Fe(II) concentrations that resulted from the activities of GBSRB4.2. PMID:22038606

  1. [Activated Sludge Bacteria Transforming Cyanopyridines and Amides of Pyridinecarboxylic Acids].

    PubMed

    Demakov, V A; Vasil'ev, D M; Maksimova, Yu G; Pavlova, Yu A; Ovechkina, G V; Maksimov, A Yu

    2015-01-01

    Species diversity of bacteria from the activated sludge of Perm biological waste treatment facilities capable of transformation of cyanopyridines and amides of pyridinecarboxylic acids was investigated. Enrichment cultures in mineral media with 3-cyanopyridine as the sole carbon and nitrogen source were used to obtain 32 clones of gram-negative heterotrophic bacteria exhibiting moderate growth on solid and liquid media with 3- and 4-cyanopyridine. Sequencing of the 16S rRNA gene fragments revealed that the clones with homology of at least 99% belonged to the genera Acinetobacte, Alcaligenes, Delftia, Ochrobactrum, Pseudomonas, Stenotrophomonas, and Xanthobacter. PCR analysis showed that 13 out of 32 isolates contained the sequences (-1070 bp) homologous to the nitrilase genes reported previously in Alcaligenes faecalis JM3 (GenBank, D13419.1). Nine clones were capable of nitrile and amide transformation in minimal salt medium. Acinetobacter sp. 11 h and Alcaligenes sp. osv transformed 3-cyanopyridine to nicotinamide, while most of the clones possessed amidase activity (0.5 to 46.3 mmol/(g h) for acetamide and 0.1 to 5.6 mmol/(g h) for nicotinamide). Nicotinamide utilization by strain A. faecalis 2 was shown to result in excretion of a secondary metabolite, which was identified as dodecyl acrylate at 91% probability. PMID:26263697

  2. Pseudo catalytic transformation of volatile fatty acids into fatty acid methyl esters.

    PubMed

    Jung, Jong-Min; Cho, Jinwoo; Kim, Ki-Hyun; Kwon, Eilhann E

    2016-03-01

    Instead of anaerobic digestion of biodegradable wastes for producing methane, this work introduced the transformation of acidogenesis products (VFAs) into fatty acid methyl esters (FAMEs) to validate the feasible production of short-chained fatty alcohols via hydrogenation of FAMEs. In particular, among VFAs, this work mainly described the mechanistic explanations for transforming butyric acid into butyric acid methyl ester as a case study. Unlike the conventional esterification process (conversion efficiency of ∼94%), the newly introduced esterification under the presence of porous materials via the thermo-chemical process reached up to ∼99.5%. Furthermore, the newly introduced esterification via the thermo-chemical pathway in this work showed extremely high tolerance of impurities: the conversion efficiency under the presence of impurities reached up to ∼99±0.3%; thus, the inhibition behaviors attributed from the impurities used for the experimental work were negligible. PMID:26720136

  3. Monomethylarsonous acid induces transformation of human bladder cells

    SciTech Connect

    Bredfeldt, Tiffany G.; Jagadish, Bhumasamudram; Eblin, Kylee E.; Mash, Eugene A.; Gandolfi, A. Jay . E-mail: gandolfi@pharmacy.arizona.edu

    2006-10-01

    Arsenic is a human bladder carcinogen. Arsenic is methylated to both monomethyl and dimethyl metabolites which have been detected in human urine. The trivalent methylated arsenicals are more toxic than inorganic arsenic. It is unknown if these trivalent methylated metabolites can directly cause malignant transformation in human cells. The goal of this study is determine if monomethylarsonous acid (MMA{sup III}) can induce malignant transformation in a human bladder urothelial cell line. To address this goal, a non-tumorigenic human urothelial cell line (UROtsa) was continuously exposed to 0.05 {mu}M MMA{sup III} for 52 weeks. Hyperproliferation was the first phenotypic change observed in exposed UROtsa (URO-MSC). After 12 weeks of exposure, doubling time had decreased from 42 h in unexposed control cells to 27 h in URO-MSC. Hyperproliferation continued to be a quality possessed by the URO-MSC cells after both 24 and 52 weeks of exposure to MMA{sup III}, which had a 40-50% reduction in doubling time. Throughout the 52-week exposure, URO-MSC cells retained an epithelial morphology with subtle morphological differences from control cells. 24 weeks of MMA{sup III} exposure was required to induce anchorage-independent growth as detected by colony formation in soft agar, a characteristic not found in UROtsa cells. To further substantiate that malignant transformation had occurred, URO-MSC cells were tested after 24 and 52 weeks of exposure to MMA{sup III} for the ability to form tumors in SCID mice. Enhanced tumorigenicity in SCID mouse xenografts was observed after 52 weeks of treatment with MMA{sup III}. These observations are the first demonstration of MMA{sup III}-induced malignant transformation in a human bladder urothelial cell line and provide important evidence that MMA{sup III} may be carcinogenic in human tissues.

  4. Repeats in transforming acidic coiled-coil (TACC) genes.

    PubMed

    Trivedi, Seema

    2013-06-01

    Transforming acidic coiled-coil proteins (TACC1, 2, and 3) are essential proteins associated with the assembly of spindle microtubules and maintenance of bipolarity. Dysregulation of TACCs is associated with tumorigenesis, but studies of microsatellite instability in TACC genes have not been extensive. Microsatellite or simple sequence repeat instability is known to cause many types of cancer. The present in silico analysis of SSRs in human TACC gene sequences shows the presence of mono- to hexa-nucleotide repeats, with the highest densities found for mono- and di-nucleotide repeats. Density of repeats is higher in introns than in exons. Some of the repeats are present in regulatory regions and retained introns. Human TACC genes show conservation of many repeat classes. Microsatellites in TACC genes could be valuable markers for monitoring numerical chromosomal aberrations and or cancer. PMID:23446777

  5. Preseismic anomalous telluric current signals observed in Kozu-shima Island, Japan.

    PubMed

    Orihara, Yoshiaki; Kamogawa, Masashi; Nagao, Toshiyasu; Uyeda, Seiya

    2012-11-20

    Monitoring of telluric current, which is practically a synonym for geoelectric potential difference, was conducted on Kozu-shima Island about 170 km south of Tokyo from May 14, 1997 to June 25, 2000. During the monitoring period, 19 anomalous telluric current changes (ATCs) were observed. Their possible correlation with nearby earthquakes was statistically examined by assuming various lead times for different ranges of magnitude and focal distance. The best correlation may be obtained for earthquakes with a magnitude greater than 3.0 occurring within 20 km of focal distance. There were 23 such earthquakes, of which 11 were preceded by ATCs within 30 d. Of these 11 earthquakes, preceding ATCs of 5 and 6 were positive and negative polarities of telluric current, respectively. Their epicenters were spatially well clustered in the east and west of the island. These facts were clearly beyond those expected by chance and led to a simple speculative model. PMID:23115337

  6. Preseismic anomalous telluric current signals observed in Kozu-shima Island, Japan

    PubMed Central

    Orihara, Yoshiaki; Kamogawa, Masashi; Nagao, Toshiyasu; Uyeda, Seiya

    2012-01-01

    Monitoring of telluric current, which is practically a synonym for geoelectric potential difference, was conducted on Kozu-shima Island about 170 km south of Tokyo from May 14, 1997 to June 25, 2000. During the monitoring period, 19 anomalous telluric current changes (ATCs) were observed. Their possible correlation with nearby earthquakes was statistically examined by assuming various lead times for different ranges of magnitude and focal distance. The best correlation may be obtained for earthquakes with a magnitude greater than 3.0 occurring within 20 km of focal distance. There were 23 such earthquakes, of which 11 were preceded by ATCs within 30 d. Of these 11 earthquakes, preceding ATCs of 5 and 6 were positive and negative polarities of telluric current, respectively. Their epicenters were spatially well clustered in the east and west of the island. These facts were clearly beyond those expected by chance and led to a simple speculative model. PMID:23115337

  7. Plants having modified response to ethylene by transformation with an ETR nucleic acid

    DOEpatents

    Meyerowitz, Elliott M.; Chang, Caren; Bleecker, Anthony B.

    2001-01-01

    The invention includes transformed plants having at least one cell transformed with a modified ETR nucleic acid. Such plants have a phenotype characterized by a decrease in the response of at least one transformed plant cell to ethylene as compared to a plant not containing the transformed plant cell. Tissue and/or temporal specificity for expression of the modified ETR nucleic acid is controlled by selecting appropriate expression regulation sequences to target the location and/or time of expression of the transformed nucleic acid. The plants are made by transforming at least one plant cell with an appropriate modified ETR nucleic acid, regenerating plants from one or more of the transformed plant cells and selecting at least one plant having the desired phenotype.

  8. A final report on computed magneto-telluric curves for hypothetical models of crustal structure

    USGS Publications Warehouse

    Pritchard, J.I.

    1965-01-01

    Several mathematical models were investigated to determine the capa-bilities of the magneto-telluric method for determining the resistivity structure of the earth's crust. The model parameters were based on the crust model proposed by Keller (1963). The mathematical technique used was developed by Cagniard (1953). The investigations indicate that a three-layer model approximation of the crust and mantle is the most detailed model warranted in inter-preting the information provided by the magneto-telluric method about the lower crust. Only the thickness of the lower crust can be determined, and not the resistivity.

  9. Dissimilatory reduction and transformation of ferrihydrite-humic acid coprecipitates.

    PubMed

    Shimizu, Masayuki; Zhou, Jihai; Schrder, Christian; Obst, Martin; Kappler, Andreas; Borch, Thomas

    2013-01-01

    Organic matter (OM) is present in most terrestrial environments and is often found coprecipitated with ferrihydrite (Fh). Sorption or coprecipitation of OM with Fe oxides has been proposed to be an important mechanism for long-term C preservation. However, little is known about the impact of coprecipitated OM on reductive dissolution and transformation of Fe(III) (oxyhydr)oxides. Thus, we study the effect of humic acid (HA) coprecipitation on Fh reduction and secondary mineral formation by the dissimilatory Fe(III)-reducing bacterium Shewanella putrefaciens strain CN32. Despite similar crystal structure for all coprecipitates investigated, resembling 2-line Fh, the presence of coprecipitated HA resulted in lower specific surface areas. In terms of reactivity, coprecipitated HA resulted in slower Fh bioreduction rates at low C/Fe ratios (i.e., C/Fe ? 0.8), while high C/Fe ratios (i.e., C/Fe ? 1.8) enhanced the extent of bioreduction compared to pure Fh. The coprecipitated HA also altered the secondary Fe mineralization pathway by inhibiting goethite formation, reducing the amount of magnetite formation, and increasing the formation of a green rust-like phase. This study indicates that coprecipitated OM may influence the rates, pathway, and mineralogy of biogeochemical Fe cycling and anaerobic Fe respiration within soils. PMID:24219167

  10. Modelling telluric line spectra in the optical and infrared with an application to VLT/X-Shooter spectra

    NASA Astrophysics Data System (ADS)

    Rudolf, N.; Günther, H. M.; Schneider, P. C.; Schmitt, J. H. M. M.

    2016-01-01

    Context. Earth's atmosphere imprints a large number of telluric absorption and emission lines on astronomical spectra, especially in the near infrared, that need to be removed before analysing the affected wavelength regions. Aims: These lines are typically removed by comparison to A- or B-type stars used as telluric standards that themselves have strong hydrogen lines, which complicates the removal of telluric lines. We have developed a method to circumvent that problem. Methods: For our IDL software package tellrem we used a recent approach to model telluric absorption features with the line-by-line radiative transfer model (LBLRTM). The broad wavelength coverage of the X-Shooter at VLT allows us to expand their technique by determining the abundances of the most important telluric molecules H2O, O2, CO2, and CH4 from sufficiently isolated line groups. For individual observations we construct a telluric absorption model for most of the spectral range that is used to remove the telluric absorption from the object spectrum. Results: We remove telluric absorption from both continuum regions and emission lines without systematic residuals for most of the processable spectral range; however, our method increases the statistical errors. The errors of the corrected spectrum typically increase by 10% for S/N ~ 10 and by a factor of two for high-quality data (S/N ~ 100), i.e. the method is accurate on the percent level. Conclusions: Modelling telluric absorption can be an alternative to the observation of standard stars for removing telluric contamination. Based on observations collected at the European Southern Observatory, Paranal, Chile, 085.C-0764(A) and 60.A-9022(C).The tellrem package is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/585/A113

  11. Postreplication repair of ultraviolet-irradiated transforming deoxyribonucleic acid in Bacillus subtilis

    SciTech Connect

    Hadden, C.T.

    1981-01-01

    Repair of ultraviolet-irradiated transforming deoxyribonucleic acid (DNA) in several strains of Bacillus subtilis was studied in order to determine the effects of excision repair and postreplication repair on transformation. Two mutations that cause a Uvr/sup -/ phenotype (uvr-1 and uvr-42) were shown to have strikingly different effects on repair of ultraviolet-irradiated transforming DNA.

  12. Molecfit: A general tool for telluric absorption correction. I. Method and application to ESO instruments

    NASA Astrophysics Data System (ADS)

    Smette, A.; Sana, H.; Noll, S.; Horst, H.; Kausch, W.; Kimeswenger, S.; Barden, M.; Szyszka, C.; Jones, A. M.; Gallenne, A.; Vinther, J.; Ballester, P.; Taylor, J.

    2015-04-01

    Context. The interaction of the light from astronomical objects with the constituents of the Earth's atmosphere leads to the formation of telluric absorption lines in ground-based collected spectra. Correcting for these lines, mostly affecting the red and infrared region of the spectrum, usually relies on observations of specific stars obtained close in time and airmass to the science targets, therefore using precious observing time. Aims: We present molecfit, a tool to correct for telluric absorption lines based on synthetic modelling of the Earth's atmospheric transmission. Molecfit is versatile and can be used with data obtained with various ground-based telescopes and instruments. Methods: Molecfit combines a publicly available radiative transfer code, a molecular line database, atmospheric profiles, and various kernels to model the instrument line spread function. The atmospheric profiles are created by merging a standard atmospheric profile representative of a given observatory's climate, of local meteorological data, and of dynamically retrieved altitude profiles for temperature, pressure, and humidity. We discuss the various ingredients of the method, its applicability, and its limitations. We also show examples of telluric line correction on spectra obtained with a suite of ESO Very Large Telescope (VLT) instruments. Results: Compared to previous similar tools, molecfit takes the best results for temperature, pressure, and humidity in the atmosphere above the observatory into account. As a result, the standard deviation of the residuals after correction of unsaturated telluric lines is frequently better than 2% of the continuum. Conclusions: Molecfit is able to accurately model and correct for telluric lines over a broad range of wavelengths and spectral resolutions. The accuracy reached is comparable to or better than the typical accuracy achieved using a telluric standard star observation. The availability of such a general tool for telluric absorption correction may improve future observational and analysing strategies, as well as empower users of archival data. Molecfit is available at http://www.eso.org/pipelines/skytoolsBased on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme IDs: 60.A-9100, 60.A-9452, 076.C-0129, 075.A-0603, 079.D-0374, 080.D-0526, 290.C-5022, 092.D-0024, 084.D-0912, 085.D-0161, 086.D-0066, and 088.D-0109.

  13. Telluric Line Effect on High Precision Radial Velocity Survey of K and M Dwarfs

    NASA Astrophysics Data System (ADS)

    Sithajan, Sirinrat; Ge, Jian; Wang, Ji

    2016-01-01

    The red and NIR region, where K and M dwarfs emit most of light, is the desirable region for radial velocity (RV) measurements for detecting low mass planets, but this wavelength region is heavily contaminated with telluric absorption lines. Variation in the telluric line depths and centroids can result in large RV measurement uncertainties, limiting the sensitivity to detect low mass planets. Here we use simulations to study effect of telluric removal and the residuals on RV measurements and determine the level of correction needed to minimize the effect. Simulated spectra from three representative spectrographs with spectral resolutions, R=60K, 80K, 100K and 120K for wavelength coverage at 0.38-0.62 ?m (called the optical spectrograph), 0.38-0.90 ?m (called the broad optical spectrograph) and 0.90-2.4 ?m (called the NIR spectrograph), have been studied. Two methods are used to study the RV effect by the telluric lines. The first one is a 'Masking' method, in which the telluric lines are identified and removed from RV calculation. The other method is a 'Removal' method, in which all heavily saturated lines are masked out and the remaining lines are subtracted by synthetic atmospheric spectra to a desired level. Our results show that, in case of late M dwarfs, the broad optical spectrograph can gain additional RV sensitivity over the optical spectrograph if telluric lines can be modeled and subtracted to better than 10%, or all lines deeper than 5% are masked out from RV calculation. For the earlier type stars, it requires better than 2% modeling and subtracting precision with the broad optical spectrograph to gain additional Doppler sensitivity over the optical spectrograph. Besides the photon gain with the NIR spectrograph over the optical spectrograph for late M dwarf observations, the NIR can gain additional advantage of Doppler sensitivity over the optical tool for late M dwarfs when telluric residuals can be subtracted to below 1%. However, it is never better than the broad optical spectrograph in any cases with the same residual levels. These indicate the broad optical spectrograph can potentially be an optimal spectrograph for high precision RV surveys for low mass planets.

  14. Formation and transformation of amino acids and amino acid precursors by high-velocity impacts

    NASA Astrophysics Data System (ADS)

    Kaneko, T.; Kobayashi, K.; Yamori, A.

    A wide variety of organic compounds have been found in extraterrestrial bodies such as comets and carbonaceous chondrites. It is plausible that these extraterrestrial bodies carried organic compounds such as amino acids or their precursors to the early Earth. It is claimed, however, that these extraterrestrial organics were destroyed during impacts to the Earth. We therefore examined possible transformation of amino acids and their precursors during high-velocity impacts by using a rail gun "HYPAC" in ISAS. Starting materials used in the impact experiments were (i) aqueous solution of glycine (10 mM or 1.0 M), and (ii) a mixture of ammonia, methanol and water. The target materials were sealed in stainless steel capsules, and shocked by impact with a polycarbonate projectile accelerated with "HYPAC" to the velocities of 2.5 - 7.0 km/s. A part of the products was acid-hydrolyzed. Both hydrolyzed an unhydrolyzed products were analyzed by mass spectrometry, high performance liquid chromatography and capillary electrophoresis and chromatography. When an aqueous solution containing ammonia, methanol and water was shocked by impact at the velocity of 6.4 km/s, a number of amino acids (e.g., serine and glycine) were detected after hydrolysis. The present results suggest that amino acid precursors could be formed during cometary impacts. When glycine solution was used as a starting material, about 40 % of glycine was recovered even after 6 km/s impact. Methylamine and ammonia, which are known as pyrolytic products of glycine, were detected, besides them, diketopiperazine and an unidentified product whose molecular weight was 134, were detected, while no glycine peptides were identified in them. It was shown that the impact processes resulted in the formation of amino acid condensates. Thermal stability of glycine precursor is comparable with glycine. The present results suggest that organic material could survive and/or formed during an impact process. Most of organic compounds in comets and carbonaceous chondrites were complex organic compounds. Laboratory simulations suggest that they contain precursors of amino acids. We are examining possible alteration of such complex precursors of amino acids by high-velocity impacts.

  15. Transformation of chlorinated phenols and anilines in the presence of humic acid

    SciTech Connect

    Park, J.W.; Dec, J.; Kim, J.E.; Bollag, J.M.

    2000-02-01

    Incubations of chlorinated phenols and anilines with oxidoreductive catalysts (peroxidase, laccase, tyrosinase, and birnessite) in the presence of humic acid led to oligomerization of the substrates or their binding to organic matter. The effect of humic acid on the overall transformation depended on the substrate, type of catalyst, and the concentration and source of humic acid. At low humic acid concentrations, the transformation of 4-chlorophenol (4-CP) was enhanced, but at higher concentrations of humic acid, no further enhancement occurred. The transformation of 4-chloroaniline (4-CA) was only slightly affected after the addition of humic acid. In experiments with {sup 14}C-labeled substrates, 4-CP was mainly bound to humic acid and formed few oligomers, whereas 4-CA was largely subject to oligomerization with less binding to humic acid. Binding and oligomerization of 4-CP did not change with increasing concentration of humic acid, but with 4-CA, binding increased and oligomerization decreased. It appears that nucleophilic binding of 4-CA depended largely on the availability of carbonyl and quinone groups in humic acid and, therefore, the distribution of the transformed substrate between oligomers and organic matter greatly depended on the source of humic acid.

  16. Acid-catalyzed transformation of ionophore veterinary antibiotics: reaction mechanism and product implications.

    PubMed

    Sun, Peizhe; Yao, Hong; Minakata, Daisuke; Crittenden, John C; Pavlostathis, Spyros G; Huang, Ching-Hua

    2013-07-01

    Ionophore antibiotics (IPAs) are polyether antimicrobials widely used in the livestock industry and may enter the environment via land application of animal waste and agricultural runoff. Information is scarce regarding potential transformation of IPAs under environmental conditions. This study is among the first to identify the propensity of IPAs to undergo acid-catalyzed transformation in mildly acidic aquatic systems and characterize the reactions in depth. The study focused on the most widely used monensin (MON) and salinomycin (SAL), and also included narasin (NAR) in the investigation. All three IPAs are susceptible to acid-catalyzed transformation. MON reacts much more slowly than SAL and NAR and exhibits a different kinetic behavior that is further evaluated by a reversible reaction kinetic model. Extensive product characterization identifies that the spiro-ketal group of IPAs is the reactive site for the acid-catalyzed hydrolytic transformation, yielding predominantly isomeric and other products. Toxicity evaluation of the transformation products shows that the products retain some antimicrobial properties. The occurrence of IPAs and isomeric transformation products is also observed in poultry litter and agricultural runoff samples. Considering the common presence of mildly acidic environments (pH 4-7) in soils and waters, the acid-catalyzed transformation identified in this study likely plays an important role in the environmental fate of IPAs. PMID:23373828

  17. Organic amendment effects on the transformation and fractionation of aluminum in acidic sandy soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was attempted to evaluate the transformation of aluminum (Al) in an acidic sandy soil amended with composts (yard waste, yard + municipal waste, GreenEdge, and synthetic humic acid), based on soil Al fractionation by single and sequential extraction. The compost amendment significantly i...

  18. The rolC gene increases caffeoylquinic acid production in transformed artichoke cells.

    PubMed

    Vereshchagina, Y V; Bulgakov, V P; Grigorchuk, V P; Rybin, V G; Veremeichik, G N; Tchernoded, G K; Gorpenchenko, T Y; Koren, O G; Phan, N H T; Minh, N T; Chau, L T; Zhuravlev, Y N

    2014-09-01

    Caffeoylquinic acids are found in artichokes, and they are currently considered important therapeutic or preventive agents for treating Alzheimer's disease and diabetes. We transformed artichoke [the cultivated cardoon or Cynara cardunculus var. altilis DC (Asteraceae)] with the rolC gene, which is a known inducer of secondary metabolism. High-performance liquid chromatography with UV and high-resolution mass spectrometry (HPLC-UV-HRMS) revealed that the predominant metabolites synthesized in the transgenic calli were 1,5-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, and chlorogenic acid. The rolC-transformed calli contained 1.5% caffeoylquinic acids by dry weight. The overall production of these metabolites was three times higher than that of the corresponding control calli. The enhancing effect of rolC remained stable over long-term cultivation. PMID:24938208

  19. Adding value to plant oils and fatty acids: Biological transformation of fatty acids into ?-hydroxycarboxylic, ?,?-dicarboxylic, and ?-aminocarboxylic acids.

    PubMed

    Seo, Joo-Hyun; Lee, Sun-Mee; Lee, Jinwon; Park, Jin-Byung

    2015-12-20

    Not only short chain ?-hydroxycarboxylic acids, ?,?-dicarboxylic acids, and ?-aminocarboxylic acids but also medium to long chain carboxylic acids are widely used as building blocks and intermediates in the chemical, pharmaceutical, and food industries. Thereby, recent achievements in biological production of medium to long chain carboxylic acids are addressed here. ?-Hydroxycarboxylic and ?,?-dicarboxylic acids were synthesized via terminal CH bond oxygenation of fatty acids and/or internal oxidative cleavage of the fatty acid carbon skeletons. ?-Aminocarboxylic acids were enzymatically produced from ?-hydroxycarboxylic acids via ?-oxocarboxylic acids. Productivities and product yields of some of the products are getting close to the industrial requirements for large scale production. PMID:26546054

  20. Molecfit: A general tool for telluric absorption correction. II. Quantitative evaluation on ESO-VLT/X-Shooterspectra

    NASA Astrophysics Data System (ADS)

    Kausch, W.; Noll, S.; Smette, A.; Kimeswenger, S.; Barden, M.; Szyszka, C.; Jones, A. M.; Sana, H.; Horst, H.; Kerber, F.

    2015-04-01

    Context. Absorption by molecules in the Earth's atmosphere strongly affects ground-based astronomical observations. The resulting absorption line strength and shape depend on the highly variable physical state of the atmosphere, i.e. pressure, temperature, and mixing ratio of the different molecules involved. Usually, supplementary observations of so-called telluric standard stars (TSS) are needed to correct for this effect, which is expensive in terms of telescope time. We have developed the software package molecfit to provide synthetic transmission spectra based on parameters obtained by fitting narrow ranges of the observed spectra of scientific objects. These spectra are calculated by means of the radiative transfer code LBLRTM and an atmospheric model. In this way, the telluric absorption correction for suitable objects can be performed without any additional calibration observations of TSS. Aims: We evaluate the quality of the telluric absorption correction using molecfit with a set of archival ESO-VLT/X-Shooter visible and near-infrared spectra. Methods: Thanks to the wavelength coverage from the U to the K band, X-Shooter is well suited to investigate the quality of the telluric absorption correction with respect to the observing conditions, the instrumental set-up, input parameters of the code, the signal-to-noise of the input spectrum, and the atmospheric profiles. These investigations are based on two figures of merit, Ioff and Ires, that describe the systematic offsets and the remaining small-scale residuals of the corrections. We also compare the quality of the telluric absorption correction achieved with molecfit to the classical method based on a telluric standard star. Results: The evaluation of the telluric correction with molecfit shows a convincing removal of atmospheric absorption features. The comparison with the classical method reveals that molecfit performs better because it is not prone to the bad continuum reconstruction, noise, and intrinsic spectral features introduced by the telluric standard star. Conclusions: Fitted synthetic transmission spectra are an excellent alternative to the correction based on telluric standard stars. Moreover, molecfit offers wide flexibility for adaption to various instruments and observing sites. http://www.eso.org/sci/software/pipelines/skytools/

  1. The investigation of the dynamics of the phase transformation in triolein and oleic acid under pressure

    NASA Astrophysics Data System (ADS)

    Tefelski, D. B.; Siegoczyński, R. M.; Rostocki, A. J.; Kos, A.; Kościesza, R.; Wieja, K.

    2008-07-01

    An aim of our work is the understanding of processes happening during phase transformations under the pressure in triglycerides and unsaturated fatty acids. Particles of investigated liquids possess the double bond between carbon atoms, which causes the bended shape of the particle and makes its free rotation impossible. This property causes low temperatures of melting point and high temperatures of boiling and also investigated by us phase transformations. For study of the dynamics of phase transformation in these liquids we measured light transmission and light scattering at 90 degrees angle, temperature, permittivity and internal pressure versus time. We applied pressure using computer controlled pump with a stepping motor, which makes increase of the pressure steady. The phase transformation in oleic acid lasts several seconds, in triolein it lasts several minutes. We think that the elongated time of phase transformation is caused by a hooked shape of particles of triolein and the dynamics of that process is determined by the tangling of particles. We checked the influence of smaller particles of oleic acid on the phase transformation by investigating the mixture of these liquids.

  2. Organic acid derivatization techniques applied to petroleum hydrocarbon transformations in subsurface environments

    SciTech Connect

    Barcelona, M.J.; Lu, J.; Tomczak, D.M.

    1995-07-01

    Evidence for the natural microbial remediation of subsurface fuel contamination situations should include identification and analysis of transformation or degradation products. In this way, a mass balance between fuel constituents and end products may be approached to monitor cleanup progress. Application of advanced organic acid metabolite derivatization techniques to several know sites of organic compounds and fuel mixture contamination provide valuable information on the pathways and progress of microbial transformation. Good correlation between observed metabolites and transformation pathways of aromatic fuel constituents were observed at the sites.

  3. Fatty acid chain flexibility in the membranes of normal and transformed fibroblasts.

    PubMed Central

    Gaffney, B J

    1975-01-01

    Fatty acid spin labels were used to measure the inherent flexibility of the lipid acyl chains in intact cell membranes of 3T3 mouse fibroblasts and several varieties of transformed 3T3 cells. No significant differences in inherent lipid flexibility were detected in the normal and transformed mouse fibroblasts. These results are compared with similar results obtained earlier for chick embryo fibroblasts. For the cells studied, a difference in the mobility of membrane glycoproteins of normal and transformed fibroblasts has either been demonstrated directly or inferred from differential agglutinability by other investigations. Therefore, a basis for correlating glycoprotein mobility and lipid motion in these cells was not found. PMID:164663

  4. Abundance and rotational temperature of telluric methane as determined from the 2 nu 3 band

    NASA Technical Reports Server (NTRS)

    Margolis, J. S.; Martonchik, J.; Beer, R.; Norton, R. H.

    1974-01-01

    The rotational temperature of the 2 nu 3 methane absorptions in the solar/telluric spectrum and the methane abundance in the earth's atmosphere have been measured and are found to be 243.4 plus or minus 5.3 K and 1.137 plus or minus 0.117 cm-atm (STP) in a vertical column, respectively. The data were reduced using the results of laboratory measurements with proper allowance for the fine-structure of the methane absorption manifold and the effects of vibration-rotation interaction (which causes an enhancement of the R-branch of this band).

  5. Demonstration of Infectious Deoxyribonucleic Acid in Transformed Cells I. Recovery of Simian Virus 40 from Yielder and Nonyielder Transformed Cells

    PubMed Central

    Boyd, Virginia A. L.; Butel, Janet S.

    1972-01-01

    Deoxyribonucleic acid (DNA) was extracted from virus-free simian virus 40 (SV40)-transformed hamster, mouse, and monkey cells and was inoculated into simian cells in the presence of diethylaminoethyl (DEAE)-dextran; infectious SV40 was recovered by using DNA from cell lines which fail to yield virus by the fusion technique as well as from cell lines which readily yield virus by fusion. The rescued virus was identified as SV40 by three methods: (i) neutralization of plaque formation by specific antiserum; (ii) induction of synthesis of viral-specific antigens detected by immunofluorescence; and (iii) presence of papovavirus particles seen by the electron microscope. Treatment of the transformed cell DNA with deoxyribonuclease or omission of the DEAE-dextran prevented the rescue of virus. Large amounts of transformed cell DNA were required (>10 ?g/culture of 106 cells) to effect rescue of SV40 by passage through monkey cells. A linear response was obtained between the input of DNA with inocula between 10 and 45 ?g of DNA/culture and the yield of SV40 recovered. Biological activity was demonstrable irregularly when the transformed cell DNA was assayed directly in the presence of DEAE-dextran. The DNA induced plaque formation in about 50% of the trials as well as the synthesis of SV40 tumor and viral antigens in rare simian cells. The infectious DNA appeared to be associated with cellular DNA. The infectivity was found in the pellet of precipitated DNA obtained by the Hirt technique and was inactivated by boiling for 15 min. These properties are characteristic of linear cellular DNA and not of free, circular SV40 DNA. PMID:4342048

  6. Heterogeneous catalysts for the transformation of fatty acid triglycerides and their derivatives to fuel hydrocarbons

    NASA Astrophysics Data System (ADS)

    Yakovlev, Vadim A.; Khromova, Sofia A.; Bukhtiyarov, Valerii I.

    2011-10-01

    The results of studies devoted to the catalysts for transformation of fatty acid triglycerides and their derivatives to fuel hydrocarbons are presented and described systematically. Various approaches to the use of heterogeneous catalysts for the production of biofuel from these raw materials are considered. The bibliography includes 134 references.

  7. RETINOIDAL BENZOIC ACIDS (AROTENOIDS) AND OTHER RETINOIDS INHIBIT IN VITRO TRANSFORMATION OF EPITHELIAL CELLS

    EPA Science Inventory

    Five retinoids were calcluated for their ability to inhibit N-methyl-N'nitro-N-nitrosoguanidine (MNNG)-induccd transformation of primary rat trachcal epithelial (RTE) cells in culture at concentrations that did not affect cell survival. wo retinoidal benzoic acids (arotcnoids), R...

  8. TRANSFORMATION

    SciTech Connect

    LACKS,S.A.

    2003-10-09

    Transformation, which alters the genetic makeup of an individual, is a concept that intrigues the human imagination. In Streptococcus pneumoniae such transformation was first demonstrated. Perhaps our fascination with genetics derived from our ancestors observing their own progeny, with its retention and assortment of parental traits, but such interest must have been accelerated after the dawn of agriculture. It was in pea plants that Gregor Mendel in the late 1800s examined inherited traits and found them to be determined by physical elements, or genes, passed from parents to progeny. In our day, the material basis of these genetic determinants was revealed to be DNA by the lowly bacteria, in particular, the pneumococcus. For this species, transformation by free DNA is a sexual process that enables cells to sport new combinations of genes and traits. Genetic transformation of the type found in S. pneumoniae occurs naturally in many species of bacteria (70), but, initially only a few other transformable species were found, namely, Haemophilus influenzae, Neisseria meningitides, Neisseria gonorrheae, and Bacillus subtilis (96). Natural transformation, which requires a set of genes evolved for the purpose, contrasts with artificial transformation, which is accomplished by shocking cells either electrically, as in electroporation, or by ionic and temperature shifts. Although such artificial treatments can introduce very small amounts of DNA into virtually any type of cell, the amounts introduced by natural transformation are a million-fold greater, and S. pneumoniae can take up as much as 10% of its cellular DNA content (40).

  9. Transformation of Monoaromatic hydrocarbons to organic acids in anoxic groundwater environment

    USGS Publications Warehouse

    Cozzarelli, I.M.; Eganhouse, R.P.; Baedecker, M.J.

    1990-01-01

    The transformation of benzene and a series of alkylbenzenes was studied in anoxic groundwater of a shallow glacial-outwash aquifer near Bemidji, Minnesota, U.S.A. Monoaromatic hydrocarbons, the most water-soluble components of crude oil, were transported downgradient of an oil spill, forming a plume of contaminated groundwater. Organic acids that were not original components of the oil were identified in the anoxic groundwater. The highest concentrations of these oxidized organic compounds were found in the anoxic plume where a decrease in concentrations of structurally related alkylbenzenes was observed. These results suggest that biological transformation of benzene and alkylbenzenes to organic acid intermediates may be an important attenuation process in anoxic environments. The transformation of a complex mixture of hydrocarbons to a series of corresponding oxidation products in an anoxic subsurface environment provides new insight into in situ anaerobic degradation processes. ?? 1990 Springer-Verlag New York Inc.

  10. Potential of endophytic fungus Phomopsis liquidambari for transformation and degradation of recalcitrant pollutant sinapic acid.

    PubMed

    Xie, Xing-Guang; Huang, Chun-Yan; Fu, Wan-Qiu; Dai, Chuan-Chao

    2016-03-01

    The biodegradation potential of sinapic acid, one of the most representative methoxy phenolic pollutants presented in industrial wastewater, was first studied using an endophytic fungus called Phomopsis liquidambari. This strain can effectively degrade sinapic acid in flasks and in soil and the possible biodegradation pathway was first systematically proposed on the basis of the metabolite production patterns and the identification of the metabolites by GC-MS and HPLC-MS. Sinapic acid was first transformed to 2,6-dimethoxy-4-vinylphenol that was further degraded via 4-hydroxy-3,5-dimethoxybenzaldehyde, syringic acid, gallic acid, and citric acid which involved in the continuous catalysis by phenolic acid decarboxylase, laccase, and gallic acid dioxygenase. Moreover, their activities and gene expression levels exhibited a 'cascade induction' response with the changes in metabolic product concentrations and the generation of fungal laccase significantly improved the degradation process. This study is the first report of an endophytic fungus that has great potential to degrade xenobiotic sinapic acid, and also provide a basis for practical application of endophytic fungus in the bioremediation of sinapic acid-contaminated industrial wastewater and soils. PMID:26895869

  11. Chemoselective Transformation of Diarylethanones to Arylmethanoic Acids and Diarylmethanones and Mechanistic Insights.

    PubMed

    Wang, Xing; Chen, Rui-Xi; Wei, Zeng-Feng; Zhang, Chen-Yang; Tu, Hai-Yang; Zhang, Ai-Dong

    2016-01-01

    The chemoselective transformation of diarylethanones via either aerobic oxidative cleavage to give arylmethanoic acids or tandem aerobic oxidation/benzilic acid rearrangement/decarboxylation to give diarylmethanones has been developed. The transformation is controllable and applicable to a broad spectrum of substrates and affords the desired products in good to excellent yields. Mechanistic insights with control reactions, (1)H NMR tracking, and single-crystal X-ray diffraction reveal a complex mechanistic network in which two common intermediates, ?-ketohydroperoxide and diarylethanedione, and three plausible pathways are proposed and verified. These pathways are interlinked and can be switched reasonably by changing the reaction conditions. This method enables scalable synthesis and access to a number of valuable compounds, including vitamin B3, diphenic acid, and the nonsteroidal anti-inflammatory drug ketoprofen. The present protocol represents a step forward in exploiting complex mechanistic networks to control reaction pathways, achieving divergent syntheses from the same class of starting materials. PMID:26618373

  12. TRANSFORMER

    DOEpatents

    Baker, W.R.

    1959-08-25

    Transformers of a type adapted for use with extreme high power vacuum tubes where current requirements may be of the order of 2,000 to 200,000 amperes are described. The transformer casing has the form of a re-entrant section being extended through an opening in one end of the cylinder to form a coaxial terminal arrangement. A toroidal multi-turn primary winding is disposed within the casing in coaxial relationship therein. In a second embodiment, means are provided for forming the casing as a multi-turn secondary. The transformer is characterized by minimized resistance heating, minimized external magnetic flux, and an economical construction.

  13. Valproic acid defines a novel class of HDAC inhibitors inducing differentiation of transformed cells

    PubMed Central

    Gttlicher, Martin; Minucci, Saverio; Zhu, Ping; Krmer, Oliver H.; Schimpf, Annemarie; Giavara, Sabrina; Sleeman, Jonathan P.; Lo Coco, Francesco; Nervi, Clara; Pelicci, Pier Giuseppe; Heinzel, Thorsten

    2001-01-01

    Histone deacetylases (HDACs) play important roles in transcriptional regulation and pathogenesis of cancer. Thus, HDAC inhibitors are candidate drugs for differentiation therapy of cancer. Here, we show that the well-tolerated antiepileptic drug valproic acid is a powerful HDAC inhibitor. Valproic acid relieves HDAC-dependent transcriptional repression and causes hyperacetylation of histones in cultured cells and in vivo. Valproic acid inhibits HDAC activity in vitro, most probably by binding to the catalytic center of HDACs. Most importantly, valproic acid induces differentiation of carcinoma cells, transformed hematopoietic progenitor cells and leukemic blasts from acute myeloid leukemia patients. More over, tumor growth and metastasis formation are significantly reduced in animal experiments. Therefore, valproic acid might serve as an effective drug for cancer therapy. PMID:11742974

  14. Characteristics of Palm Fatty Acid Ester (PFAE), a New Vegetable Based Insulating Oil for Transformers

    NASA Astrophysics Data System (ADS)

    Suzuki, Takashi; Kanoh, Takaaki; Koide, Hidenobu; Hikosaka, Tomoyuki

    We have developed new vegetable based insulating oil for transformers called PFAE (Palm Fatty Acid Ester). PFAE has 0.6 times less viscosity and 1.3 times higher dielectric constant compared to mineral oil. The oxidative stability, biodegradability and acute toxicity to fish of PFAE has also been determined to be superior to mineral oil. In this paper, in order to optimize the characteristics of fatty acid esters originating from palm oil, several kinds of fatty acid alkyl esters were first synthesized in the laboratory by the molecular design technique and the transesterification from fatty acid methyl esters and alkyl alcohols. Next the electro-chemical characteristics of the fatty acid alkyl esters as insulating oil were analyzed.

  15. [Proteomic analysis of Bacillus subtilis 168 transforming cis-propenylphosphonic acid to fosfomycin].

    PubMed

    Xie, Fuhong; Chao, Yapeng; Shi, Jiaji; Zhang, Guoqing; Yang, Jing; Qian, Shijun

    2013-06-01

    In this study, we investigated the mechanism of transformation by Bacillus subtilis strain 168 by proteomic analysis. B. subtilis strain 168 was able to stereoselectively transform cis-propenylphosphonic acid (cPPA) to fosfomycin. The maximal fosfomycin production was 816.6 microg/mL after two days cultivation, with a conversion rate of 36.05%. We separated the whole cellular proteins by two-dimensional gel electrophoresis (2-DE) method, and 562 protein spots were detected in the presence of cPPA in the medium, while 527 protein spots were detected in the absence of cPPA. Of them, 98 differentially expressed protein spots were found. Among them, 52 proteins were up-regulated whereas 20 were down-regulated in the presence of cPPA in the medium, and 26 induced at the presence of cPPA. The differentially expressed proteins were analyzed by combined MS and MS/MS methods. Eighty protein spots, including 45 up-regulated proteins, 17 down-regulated proteins, and 18 induced by cPPA were identified. Based on the results of proteomic analysis, we postulated two steps of transformation: in the first step, cPPA was hydrated to 2-hydroxypropylphosphonic acid; in the second step, 2-hydroxypropylphosphonic acid was transformed to fosfomycin via a dehydrogenation reaction. PMID:24063234

  16. Anti-transforming nature of ascorbic acid and its derivatives examined by two-stage cell transformation using BALB/c 3T3 cells.

    PubMed

    Tsuchiya, T; Kato-Masatsuji, E; Tsuzuki, T; Umeda, M

    2000-11-10

    The anti-transforming effects of sodium ascorbate and its stable derivatives were examined in the two-stage transformation assay. When BALB/c 3T3 cells were treated with 0.2 microg/ml 20-methylcholanthrene as an initiator, and 100 ng/ml 12-O-tetradecanoylphorbol-13-acetate as a promoter, the addition at the promotion stage of L-ascorbic acid-2-phosphate ester magnesium (APM) was most marked in the inhibition of transformation. The inhibitory effects of sodium ascorbate and ascorbic acid-2-glucoside (AG) were comparable, but weaker than those of APM; L (+)-ascorbic acid-2-sulfate ester disodium 2H(2)O showed little effect. When phorbol 12, 13-didecanoate or tumor necrosis factor alpha (TNF-alpha) were used as promoters, APM also effectively suppressed transformation. PMID:11098084

  17. Determination of the Telluric Water Vapor Absorption Correction for Astronomical Data Obtained from the Kuiper Airborne Observatory

    NASA Technical Reports Server (NTRS)

    Erickson, E. F.; Simpson, J. P.; Kuhn, P. M.; Stearns, L. P.

    1979-01-01

    The amount of telluric water vapor along the line of sight of the Kuiper Airborne Observatory telescope as obtained concommitantly on 23 flights is compared with the NASA-Ames Michelson interferometer and with the NOAA-Boulder radiometer. A strong correlation between the two determinations exists, and a method for computing the atmospheric transmission for a given radiometer reading is established.

  18. Inhibition of Myc-induced cell transformation by brain acid-soluble protein 1 (BASP1)

    PubMed Central

    Hartl, Markus; Nist, Andrea; Khan, M. Imran; Valovka, Taras; Bister, Klaus

    2009-01-01

    Cell transformation by the Myc oncoprotein involves transcriptional activation or suppression of specific target genes with intrinsic oncogenic or tumor-suppressive potential, respectively. We have identified the BASP1 (CAP-23, NAP-22) gene as a novel target suppressed by Myc. The acidic 25-kDa BASP1 protein was originally isolated as a cortical cytoskeleton-associated protein from rat and chicken brain, but has also been found in other tissues and subcellular locations. BASP1 mRNA and protein expression is specifically suppressed in fibroblasts transformed by the v-myc oncogene, but not in cells transformed by other oncogenic agents. The BASP1 gene encompasses 2 exons separated by a 58-kbp intron and a Myc-responsive regulatory region at the 5? boundary of untranslated exon 1. Bicistronic expression of BASP1 and v-myc from a retroviral vector blocks v-myc-induced cell transformation. Furthermore, ectopic expression of BASP1 renders fibroblasts resistant to subsequent cell transformation by v-myc, and exogenous delivery of the BASP1 gene into v-myc-transformed cells leads to significant attenuation of the transformed phenotype. The inhibition of v-myc-induced cell transformation by BASP1 also prevents the transcriptional activation or repression of known Myc target genes. Mutational analysis showed that the basic N-terminal domain containing a myristoylation site, a calmodulin binding domain, and a putative nuclear localization signal is essential for the inhibitory function of BASP1. Our results suggest that down-regulation of the BASP1 gene is a necessary event in myc-induced oncogenesis and define the BASP1 protein as a potential tumor suppressor. PMID:19297618

  19. Retinoic acid modulates rat Ito cell proliferation, collagen, and transforming growth factor beta production.

    PubMed Central

    Davis, B H; Kramer, R T; Davidson, N O

    1990-01-01

    Recent studies suggest that vitamin A plays an inhibitory role with respect to "activation" of the hepatic Ito cell, a likely effector of hepatic fibrogenesis. Ito cell "activation" during fibrogenesis is characterized by a decrease in intracellular vitamin A and an increase in cellular proliferation and collagen production. To explore the hypothesis that retinoids have the capacity to diminish Ito cell activation, cultured Ito cells were exposed to retinoic acid and its effects assessed on three key features: cell proliferation, collagen protein production and mRNA abundance, and transforming growth factor beta protein production. Retinoic acid was 100-1,000X more potent than retinol with respect to inhibition of Ito cell proliferation. Interstitial collagen and transforming growth factor beta production were also reduced by 10(-6) M retinoic acid. The relative abundance of type I collagen mRNA however, was not significantly altered. By contrast, retinoic acid administration to rats caused a marked reduction in the abundance of type I collagen mRNA in both total hepatic and purified Ito cell RNA. The relative abundance of rat hepatic fibronectin or apolipoprotein E mRNA was not significantly altered. These studies demonstrate that retinoic acid can differentially modulate several key features of hepatic fibrogenesis in vitro and in vivo. Images PMID:2254460

  20. Early Intermediate State of Transforming Deoxyribonucleic Acid During Uptake by Bacillus subtilis1

    PubMed Central

    Morrison, D. A.

    1971-01-01

    Examination of the effects of ethylenediaminetetraacetic acid (EDTA) on uptake of transforming deoxyribonucleic acid (DNA) by Bacillus subtilis allowed definition of a new intermediate state of transforming DNA during uptake. Markers in this state, termed EDTA-resistant, are bound to the cell, are sensitive to inactivation by deoxyribonuclease, but may become deoxyribonuclease-resistant despite the addition of excess EDTA. Markers become EDTA-resistant quadratically with time after the addition of DNA to a competent culture, but linearly after exposure of competent cells to a brief pulse of DNA. An attractive model consistent with these findings is that EDTA blocks only the initiation of entry of a molecule of DNA. PMID:5001199

  1. Seismic and magneto-telluric imaging for geothermal exploration at Jemez pueblo in New Mexico

    SciTech Connect

    Huang, Lianjie; Albrecht, Michael

    2011-01-25

    A shallow geothermal reservoir in the Pueblo of Jemez in New Mexico may indicate a commercial-scale geothermal energy potential in the area. To explore the geothermal resource at Jemez Pueblo, seismic surveys are conducted along three lines for the purpose of imaging complex subsurface structures near the Indian Springs fault zone. A 3-D magneto-telluric (MT) survey is also carried out in the same area. Seismic and MT imaging can provide complementary information to reveal detailed geologic formation properties around the fault zones. The high-resolution seismic images will be used together with MT images, geologic mapping, and hydrogeochemistry, to explore the geothermal resource at Jemez Pueblo, and to determine whether a conunercial-scale geothermal resource exists for power generation or direct use applications after drilling and well testing.

  2. Correlation of Solar Activities with the Telluric Currents Level in the Northern Region of Malaysia

    NASA Astrophysics Data System (ADS)

    Razelan, Mazlina M.; Said, N. Masdiana Md; Aziz, A. H. A.; Chong, H. Y.; Nawawi, M.

    2010-07-01

    The relation between solar activities and the geomagnetic field induced currents (GIC) have been well studied in the auroral region and it usually occurs most frequently at high latitudes. However, during major geomagnetic storms, the auroral zone can extend substantially towards lower latitudes. Disturbance caused by solar activities can disrupt power grids and also increase the corrosion rate of buried natural gas pipelines. GIC are driven by the geomagnetic field induced by a geomagnetic disturbance. In this paper, we investigated the correlation between solar activities using the interplanetary magnetic field (IMF) and geomagnetic disturbance storm time (DST) index data with the telluric currents (also referred to as geomagnetic induced currents GIC) level through the disturbance pattern of geomagnetic field. The research areas are from Lunas in Kedah to Perlis. The pattern of geomagnetic field disturbance had been identified and analyzed to investigate the harmful effect of geomagnetic storms towards the performance of complex power grid in Malaysia.

  3. Transformation

    PubMed Central

    Knauer, Stefan H.; Rösch, Paul; Artsimovitch, Irina

    2012-01-01

    The textbook view that a primary sequence determines the unique fold of a given protein has been challenged by identification of proteins with variant structures, such as prions. Our recent studies revealed that the transcription factor RfaH simultaneously changes its topology and function. RfaH is a two-domain protein whose N-terminal domain binds to transcribing RNA polymerase, stimulating its processivity. The α-helical C-terminal domain masks the RNA polymerase-binding site of the N-terminal domain, preventing unwarranted recruitment to genes lacking a specific DNA sequence. Upon binding to its DNA target, RfaH domains dissociate, and the C-terminal domain refolds into a β-barrel. This dramatic transformation allows binding to the ribosomal protein S10 and subsequent recruitment of a ribosome, coupling transcription and translation. We define RfaH as first example of “transformer proteins”, in which two alternative structural states have distinct cellular functions and hypothesize that transformer proteins may be widespread in nature. PMID:23131843

  4. Effect of Docosahexaenoic Acid on Cell Cycle Pathways in Breast Cell Lines With Different Transformation Degree.

    PubMed

    Rescigno, Tania; Capasso, Anna; Tecce, Mario Felice

    2016-06-01

    n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), abundant in fish, have been shown to affect development and progression of some types of cancer, including breast cancer. The aim of our study was to further analyze and clarify the effects of these nutrients on the molecular mechanisms underlying breast cancer. Following treatments with DHA we examined cell viability, death, cell cycle, and some molecular effects in breast cell lines with different transformation, phenotypic, and biochemical characteristics (MCF-10A, MCF-7, SK-BR-3, ZR-75-1). These investigations showed that DHA is able to affect cell viability, proliferation, and cell cycle progression in a different way in each assayed breast cell line. The activation of ERK1/2 and STAT3 pathways and the expression and/or activation of molecules involved in cell cycle regulation such as p21(Waf1/Cip1) and p53, are very differently regulated by DHA treatments in each cell model. DHA selectively: (i) arrests non tumoral MCF-10A breast cells in G0 /G1 cycle phase, activating p21(Waf1/Cip1) , and p53, (ii) induces to death highly transformed breast cells SK-BR-3, reducing ERK1/2 and STAT3 phosphorylation and (iii) only slightly affects each analyzed process in MCF-7 breast cell line with transformation degree lower than SK-BR-3 cells. These findings suggest a more relevant inhibitory role of DHA within early development and late progression of breast cancer cell transformation and a variable effect in the other phases, depending on individual molecular properties and degree of malignancy of each clinical case. J. Cell. Physiol. 231: 1226-1236, 2016. © 2015 Wiley Periodicals, Inc. PMID:26480024

  5. INCORPORATION OF THYMIDINE AND AMINO ACIDS INTO DEOXYRIBONUCLEIC ACID AND ACID-INSOLUBLE CELL STRUCTURES IN PNEUMOCOCCAL CULTURES SYNCHRONIZED FOR COMPETENCE TO TRANSFORM

    PubMed Central

    Ephrussi-Taylor, Harriett; Freed, Barbara A.

    1964-01-01

    Ephrussi-Taylor, Harriett (Western Reserve University, Cleveland, Ohio), and Barbara A. Freed. J. Bacteriol. 87:12111215. 1964.Pneumococcal cultures, in which competence to transform develops in an acute, synchronous fashion toward the end of growth of the cultures, show an arrest in lysine incorporation into trichloroacetic acid-insoluble residues during the competent period. Thymidine incorporation into deoxyribonucleic acid is momentarily halted after the development of maximal competence. It is suggested that competence is associated with a brief arrest of normal cell-wall synthesis. PMID:4381141

  6. Production and transformation of dissolved neutral sugars and amino acids by bacteria in seawater

    NASA Astrophysics Data System (ADS)

    Jrgensen, L.; Lechtenfeld, O. J.; Benner, R.; Middelboe, M.; Stedmon, C. A.

    2014-10-01

    Dissolved organic matter (DOM) in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of combined neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining after 32 days of bacterial degradation. Results from bioassay incubations with natural seawater (sampled from water masses originating from the surface waters of the Arctic Ocean and the North Atlantic Ocean) and artificial seawater indicate that the molecular compositions following bacterial degradation are not strongly influenced by the initial substrate or bacterial community. The molecular composition of neutral sugars released by bacteria was characterized by a high glucose content (47 mol %) and heterogeneous contributions from other neutral sugars (3-14 mol %). DOM remaining after bacterial degradation was characterized by a high galactose content (33 mol %), followed by glucose (22 mol %) and the remaining neutral sugars (7-11 mol %). The ratio of D-amino acids to L-amino acids increased during the experiments as a response to bacterial degradation, and after 32 days, the D/L ratios of aspartic acid, glutamic acid, serine and alanine reached around 0.79, 0.32, 0.30 and 0.51 in all treatments, respectively. The striking similarity in neutral sugar and amino acid compositions between natural (representing marine semi-labile and refractory DOM) and artificial (representing bacterially produced DOM) seawater samples, suggests that microbes transform bioavailable neutral sugars and amino acids into a common, more persistent form.

  7. Macropinocytosis of protein is an amino acid supply route in Ras-transformed cells

    PubMed Central

    Commisso, Cosimo; Davidson, Shawn M.; Soydaner-Azeloglu, Rengin G.; Parker, Seth J.; Kamphorst, Jurre J.; Hackett, Sean; Grabocka, Elda; Nofal, Michel; Drebin, Jeffrey A.; Thompson, Craig B.; Rabinowitz, Joshua D.; Metallo, Christian M.; Heiden, Matthew G. Vander; Bar-Sagi, Dafna

    2013-01-01

    Macropinocytosis is a highly conserved endocytic process by which extracellular fluid and its contents are internalized into cells via large, heterogeneous vesicles known as macropinosomes. Oncogenic Ras proteins have been shown to stimulate macropinocytosis but the functional contribution of this uptake mechanism to the transformed phenotype remains unknown1-3. Here we show that Ras-transformed cells utilize macropinocytosis to transport extracellular protein into the cell. The internalized protein undergoes proteolytic degradation, yielding amino acids including glutamine that can enter central carbon metabolism. Accordingly, the dependence of Ras-transformed cells on free extracellular glutamine for growth can be suppressed by the macropinocytic uptake of protein. Consistent with macropinocytosis representing an important route of tumor nutrient uptake, its pharmacological inhibition compromised the growth of Ras-transformed pancreatic tumor xenografts. These results identify macropinocytosis as a mechanism by which cancer cells support their unique metabolic needs and point to the possible exploitation of this process in the design of anti-cancer therapies. PMID:23665962

  8. Photochemical transformation of an iron(iii)-arsenite complex in acidic aqueous solution.

    PubMed

    Pozdnyakov, Ivan P; Ding, Wei; Xu, Jing; Chen, Long; Wu, Feng; Grivin, Vjacheslav P; Plyusnin, Victor F

    2016-03-01

    Surface complexation between arsenious acid anions (As(iii)) and ferric (hydr)oxides in water is important for the transformation and transfer of inorganic arsenic species. The mechanisms of formation and the photochemistry of dissolved Fe(iii)-As(iii) complexes in acidic aqueous solution are still unclear. Here, the photooxidation of As(iii) in the presence of Fe(iii) ions in acidic media has been investigated by laser flash and steady-state photolysis. At low arsenite concentrations (<1 mM), As(iii) is oxidized by the ˙OH radical generated by photolysis of the FeOH(2+) complex. At higher arsenite concentrations (>10 mM), photoactive Fe(iii)-As(iii) complexes are formed (ϕ≈ 0.012). At all arsenite concentrations, a white FeAsO4 colloid is formed during As(iii) photolysis in the presence of Fe(iii) ions. Solid Fe(iii)-As(iii) complexes have been prepared and characterized, and the photochemical transformation of As(iii) into As(v) in solid Fe(iii)-As(iii) complexes has been confirmed. These findings are important for a better understanding of the evolution of As(iii) species under environmental conditions and should provide guidance for detoxification of As(iii)-polluted water systems. PMID:26906644

  9. Synthesising, using, and correcting for telluric features in high-resolution astronomical spectra . A near-infrared case study using CRIRES

    NASA Astrophysics Data System (ADS)

    Seifahrt, A.; Käufl, H. U.; Zängl, G.; Bean, J. L.; Richter, M. J.; Siebenmorgen, R.

    2010-12-01

    We present a technique to synthesise telluric absorption and emission features both for in-situ wavelength calibration and for their removal from astronomical spectra. While the presented technique is applicable for a wide variety of optical and infrared spectra, we concentrate in this paper on selected high-resolution near-infrared spectra obtained with the CRIRES spectrograph to demonstrate its performance and limitation. We find that synthetic spectra reproduce telluric absorption features to about 2%, even close to saturated line cores. Thus, synthetic telluric spectra could be used to replace the observation of telluric standard stars, saving valuable observing time. This technique also provides a precise in-situ wavelength calibration, especially useful for high-resolution near-infrared spectra in the absence of other calibration sources. Based on observations made with ESO Telescopes at the Paranal Observatory under programme IDs 60.A-9076(A), 079.D-0810(A), and 179.C-0151(A).

  10. Effects of Fe oxide on N transformations in subtropical acid soils

    NASA Astrophysics Data System (ADS)

    Jiang, Xianjun; Xin, Xiaoping; Li, Shiwei; Zhou, Junchao; Zhu, Tongbin; Mller, Christopher; Cai, Zucong; Wright, Alan L.

    2015-02-01

    Subtropical ecosystems are often characterized by high N cycling rates, but net nitrification rates are often low in subtropical acid soils. NO3--N immobilization into organic N may be a contributing factor to understand the observed low net nitrification rates in these acid soils. The effects of Fe oxide and organic matter on soil N transformations were evaluated using a 15N tracing study. Soil net nitrification was low for highly acidic yellow soil (Ferralsols), but gross ammonia oxidation was 7 times higher than net nitrification. In weakly acidic purple soil (Cambisols), net nitrification was 8 times higher than in Ferralsols. The addition of 5% Fe oxide to Cambisols, reduced the net nitrification rate to a negative rate, while NO3--N immobilization rate increased 8 fold. NO3--N immobilization was also observed in Ferralsols which contained high Fe oxides levels. A possible mechanism for these reactions could be stimulation of NO3--N immobilization by Fe oxide which promoted the abiotic formation of nitrogenous polymers, suggesting that the absence of net nitrification in some highly acid soils may be due to high rates of NO3--N immobilization caused by high Fe oxide content rather than a low pH.

  11. A microbial transformation using Bacillus subtilis B7-S to produce natural vanillin from ferulic acid.

    PubMed

    Chen, Peng; Yan, Lei; Wu, Zhengrong; Li, Suyue; Bai, Zhongtian; Yan, Xiaojuan; Wang, Ningbo; Liang, Ning; Li, Hongyu

    2016-01-01

    Bacillus subtilis strain B7-S screened from18 strains is an aerobic, endospore-forming, model organism of Gram-positive bacteria which is capable to form vanillin during ferulic acid bioconversion. The bioconversion of ferulic acid to vanillin by Bacillus subtilis B7-S (B. subtilis B7-S) was investigated. Based on our results, the optimum bioconversion conditions for the production of vanillin by B. subtilis B7-S can be summarized as follows: temperature 35?C; initial pH 9.0; inoculum volume 5%; ferulic acid concentration 0.6?g/L; volume of culture medium 20%; and shaking speed 200?r/min. Under these conditions, several repeated small-scale batch experiments showed that the maximum conversion efficiency was 63.30% after 3?h of bioconversion. The vanillin products were confirmed by spectral data achieved from UV-vis, inductively coupled plasma atomic emission spectroscope (ICP-AES) and Fourier transform infrared spectrometer (FT-IR) spectra. Scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM) results confirmed that the cell surface of B. subtilis plays a role in the induction of ferulic acid tolerance. These results demonstrate that B. subtilis B7-S has the potential for use in vanillin production through bioconversion of ferulic acid. PMID:26841717

  12. Effects of Fe oxide on N transformations in subtropical acid soils

    PubMed Central

    Jiang, Xianjun; Xin, Xiaoping; Li, Shiwei; Zhou, Junchao; Zhu, Tongbin; Mller, Christopher; Cai, Zucong; Wright, Alan L.

    2015-01-01

    Subtropical ecosystems are often characterized by high N cycling rates, but net nitrification rates are often low in subtropical acid soils. NO3?-N immobilization into organic N may be a contributing factor to understand the observed low net nitrification rates in these acid soils. The effects of Fe oxide and organic matter on soil N transformations were evaluated using a 15N tracing study. Soil net nitrification was low for highly acidic yellow soil (Ferralsols), but gross ammonia oxidation was 7 times higher than net nitrification. In weakly acidic purple soil (Cambisols), net nitrification was 8 times higher than in Ferralsols. The addition of 5% Fe oxide to Cambisols, reduced the net nitrification rate to a negative rate, while NO3?-N immobilization rate increased 8 fold. NO3?-N immobilization was also observed in Ferralsols which contained high Fe oxides levels. A possible mechanism for these reactions could be stimulation of NO3?-N immobilization by Fe oxide which promoted the abiotic formation of nitrogenous polymers, suggesting that the absence of net nitrification in some highly acid soils may be due to high rates of NO3?-N immobilization caused by high Fe oxide content rather than a low pH. PMID:25722059

  13. Effects of Fe oxide on N transformations in subtropical acid soils.

    PubMed

    Jiang, Xianjun; Xin, Xiaoping; Li, Shiwei; Zhou, Junchao; Zhu, Tongbin; Müller, Christopher; Cai, Zucong; Wright, Alan L

    2015-01-01

    Subtropical ecosystems are often characterized by high N cycling rates, but net nitrification rates are often low in subtropical acid soils. NO3(-)-N immobilization into organic N may be a contributing factor to understand the observed low net nitrification rates in these acid soils. The effects of Fe oxide and organic matter on soil N transformations were evaluated using a (15)N tracing study. Soil net nitrification was low for highly acidic yellow soil (Ferralsols), but gross ammonia oxidation was 7 times higher than net nitrification. In weakly acidic purple soil (Cambisols), net nitrification was 8 times higher than in Ferralsols. The addition of 5% Fe oxide to Cambisols, reduced the net nitrification rate to a negative rate, while NO3(-)-N immobilization rate increased 8 fold. NO3(-)-N immobilization was also observed in Ferralsols which contained high Fe oxides levels. A possible mechanism for these reactions could be stimulation of NO3(-)-N immobilization by Fe oxide which promoted the abiotic formation of nitrogenous polymers, suggesting that the absence of net nitrification in some highly acid soils may be due to high rates of NO3(-)-N immobilization caused by high Fe oxide content rather than a low pH. PMID:25722059

  14. A microbial transformation using Bacillus subtilis B7-S to produce natural vanillin from ferulic acid

    PubMed Central

    Chen, Peng; Yan, Lei; Wu, Zhengrong; Li, Suyue; Bai, Zhongtian; Yan, Xiaojuan; Wang, Ningbo; Liang, Ning; Li, Hongyu

    2016-01-01

    Bacillus subtilis strain B7-S screened from18 strains is an aerobic, endospore-forming, model organism of Gram-positive bacteria which is capable to form vanillin during ferulic acid bioconversion. The bioconversion of ferulic acid to vanillin by Bacillus subtilis B7-S (B. subtilis B7-S) was investigated. Based on our results, the optimum bioconversion conditions for the production of vanillin by B. subtilis B7-S can be summarized as follows: temperature 35 °C; initial pH 9.0; inoculum volume 5%; ferulic acid concentration 0.6 g/L; volume of culture medium 20%; and shaking speed 200 r/min. Under these conditions, several repeated small-scale batch experiments showed that the maximum conversion efficiency was 63.30% after 3 h of bioconversion. The vanillin products were confirmed by spectral data achieved from UV–vis, inductively coupled plasma atomic emission spectroscope (ICP-AES) and Fourier transform infrared spectrometer (FT-IR) spectra. Scanning electron microscopy (SEM) and transmission electron spectroscopy (TEM) results confirmed that the cell surface of B. subtilis plays a role in the induction of ferulic acid tolerance. These results demonstrate that B. subtilis B7-S has the potential for use in vanillin production through bioconversion of ferulic acid. PMID:26841717

  15. Responses of transformed Catharanthus roseus roots to femtomolar concentrations of salicylic acid.

    PubMed

    Echevarra-Machado, Ileana; Escobedo-G M, Rosa Mara; Larqu-Saavedra, Alfonso

    2007-01-01

    Catharanthus roseus transformed roots were cultured in the presence of salicylic acid (SA) at concentrations between 0.1 fM and 100 pM and the effect on root growth was evaluated. Significant morphological changes in the lateral roots were recorded on day two in the SA treatment. Presence of SA increased root cap size and caused the appearance of lateral roots closer to the root tip. The bioassay was sensitive enough to allow testing of low concentrations of other growth regulators that may affect root morphology and physiology. PMID:17544287

  16. Directional Borehole Logging Configurations Using DC and Telluric Methods for Detecting Deep Conductors Not Intersected by Wells

    NASA Astrophysics Data System (ADS)

    Asfahani, Jamal

    2005-12-01

    Herewith, two borehole directional geoelectrical configurations have been introduced for the detection of deep conductors not intersected by the well. The first one is a hole to surface configuration (HSC) using the dc current, and the second one is a telluric configuration (TC). Characterized by a deeper penetration depth, and a directional effect, both configurations have superiority comparable with other traditional geoelectrical configurations. Basically, a Directional Natural Induced Polarization methodology termed (DNIP) has been developed and proposed by benefiting from borehole telluric measurements taken at two sufficiently low frequencies. These configurations have been tested in the Rouez mine, Bretagne, France, where sulphide mineralization is known to occur. Several anomalies have been isolated in field data and interpreted by different interpretative techniques. The results obtained by applying these configurations are in good agreement, and the detected conductors are confirmed by morphological and lithological description.

  17. Pectin functionalised by fatty acids: Diffuse reflectance infrared Fourier transform (DRIFT) spectroscopic characterisation

    NASA Astrophysics Data System (ADS)

    Kamnev, Alexander A.; Calce, Enrica; Tarantilis, Petros A.; Tugarova, Anna V.; De Luca, Stefania

    2015-01-01

    Chemically modified pectin derivatives obtained by partial esterification of its hydroxyl moieties with fatty acids (FA; oleic, linoleic and palmitic acids), as well as the initial apple peel pectin were comparatively characterised using diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. Characteristic changes observed in DRIFT spectra in going from pectin to its FA esters are related to the corresponding chemical modifications. Comparing the DRIFT spectra with some reported data on FTIR spectra of the same materials measured in KBr or NaCl matrices has revealed noticeable shifts of several polar functional groups both in pectin and in its FA-esterified products induced by the halide salts. The results obtained have implications for careful structural analyses of biopolymers with hydrophilic functional groups by means of different FTIR spectroscopic methodologies.

  18. Role of Oxalic Acid Overexcretion in Transformations of Toxic Metal Minerals by Beauveria caledonica

    PubMed Central

    Fomina, M.; Hillier, S.; Charnock, J. M.; Melville, K.; Alexander, I. J.; Gadd, G. M.

    2005-01-01

    The fungus Beauveria caledonica was highly tolerant to toxic metals and solubilized cadmium, copper, lead, and zinc minerals, converting them into oxalates. This fungus was found to overexcrete organic acids with strong metal-chelating properties (oxalic and citric acids), suggesting that a ligand-promoted mechanism was the main mechanism of mineral dissolution. Our data also suggested that oxalic acid was the main mineral-transforming agent. Cadmium, copper, and zinc oxalates were precipitated by the fungus in the local environment and also in association with the mycelium. The presence of toxic metal minerals often led to the formation of mycelial cords, and in the presence of copper-containing minerals, these cords exhibited enhanced excretion of oxalic acid, which resulted in considerable encrustation of the cords by copper oxalate hydrate (moolooite). It was found that B. caledonica hyphae and cords were covered by a thick hydrated mucilaginous sheath which provided a microenvironment for chemical reactions, crystal deposition, and growth. Cryo-scanning electron microscopy revealed that mycogenic metal oxalates overgrew parental fungal hyphae, leaving a labyrinth of fungal tunnels within the newly formed mineral matter. X-ray absorption spectroscopy revealed that oxygen ligands played a major role in metal coordination within the fungal biomass during the accumulation of mobilized toxic metals by B. caledonica mycelium; these ligands were carboxylic groups in copper phosphate-containing medium and phosphate groups in pyromorphite-containing medium. PMID:15640211

  19. Perfluorobutyric acid and its monohydrate: a chirped pulse and cavity based fourier transform microwave spectroscopic study.

    PubMed

    Thomas, Javix; Serrato, Agapito; Lin, Wei; Jger, Wolfgang; Xu, Yunjie

    2014-05-12

    Rotational spectra of perfluorobutyric acid (PFBA) and its monohydrate were studied with a broadband chirped pulse and a narrow-band cavity based Fourier transform microwave spectrometer, and high-level ab initio calculations. Extensive conformational searches were performed for both the acid and its monohydrate at the MP2/6-311++G(2d,p) level of theory. Two and three conformers were predicted to exist for PFBA and its monohydrate, respectively. One set of rotational transitions was observed and assigned for each, PFBA and its monohydrate. Based on the measured broadband spectra, we confidently conclude that only one dominant conformer exists in each case. The orientation of the hydroxyl group in PFBA was determined by using isotopic analysis. Comparison of the observed transition intensities and the calculated electric dipole moment components allowed us to identify the most stable monohydrate conformation, which takes on an insertion hydrogen-bonding topology. Comparisons to the shorter chain analogues, that is, trifluoroacetic acid, perfluoropropionic acid, and their monohydrates, are made to elucidate the general trend in their conformational preference and binding topologies. PMID:24756992

  20. Requirement of mesodermal retinoic acid generated by Raldh2 for posterior neural transformation

    PubMed Central

    Molotkova, Natalia; Molotkov, Andrei; Sirbu, I. Ovidiu; Duester, Gregg

    2010-01-01

    Studies in amphibian embryos have suggested that retinoic acid (RA) may function as a signal that stimulates posterior differentiation of the nervous system as postulated by the activation-transformation model for anteroposterior patterning of the nervous system. We have tested this hypothesis in retinaldehyde dehydrogenase-2 (Raldh2) null mutant mice lacking RA synthesis in the somitic mesoderm. Raldh2/ embryos exhibited neural induction (activation) as evidenced by expression of Sox1 and Sox2 along the neural plate, but differentiation of spinal cord neuroectodermal progenitor cells (posterior transformation) did not occur as demonstrated by a loss of Pax6 and Olig2 expression along the posterior neural plate. Spinal cord differentiation in Raldh2/ embryos was rescued by maternal RA administration, and during the rescue RA was found to act directly in the neuroectoderm but not the somitic mesoderm. RA generated by Raldh2 in the somitic mesoderm was found to normally travel as a signal throughout the mesoderm and neuroectoderm of the trunk and into tailbud neuroectoderm, but not into tailbud mesoderm. Raldh2/ embryos also exhibited increased Fgf8 expression in the tailbud, and decreased cell proliferation in tailbud neuroectoderm. Our findings demonstrate that RA synthesized in the somitic mesoderm is necessary for posterior neural transformation in the mouse and that Raldh2 provides the only source of RA for posterior development. An important concept to emerge from our studies is that the somitic mesodermal RA signal acts in the neuroectoderm but not mesoderm to generate a spinal cord fate. PMID:15652703

  1. Radiation-induced neoplastic transformation of C3H10T1/2 cells is suppressed by ascorbic acid

    SciTech Connect

    Yasukawa, M.; Terasima, T.; Seki, M. )

    1989-12-01

    X-ray induced transformation of C3H10T1/2 cells was suppressed in a concentration-dependent manner by administration of ascorbic acid after irradiation (0.1-20 micrograms/ml for the first week) in the culture medium. The dose-response curve was shifted about 60% downward and was slightly steeper in the presence of ascorbic acid (5 micrograms/ml for the first week) than in its absence. The 1-week treatment procedure revealed that cells initiated by radiation remained susceptible to ascorbic acid until the time of morphological phenotype expression. The neoplastically transformed phenotype expressed after incubation for 8 weeks could no longer be suppressed by ascorbic acid even after culture transfer. Similarly, the neoplastically transformed phenotype suppressed for 8 weeks by ascorbic acid treatment was not subsequently expressed in the absence of ascorbic acid. On the basis of the oxygen-detoxifying nature of ascorbic acid, we postulated that expression of the neoplastically transformed phenotype is promoted by reactive oxygen species and peroxy radicals generated in cells during the whole assay period. The data may be useful as a guide for chemopreventive efforts against radiation carcinogenesis.

  2. A Rare Phaeodactylum tricornutum Cruciform Morphotype: Culture Conditions, Transformation and Unique Fatty Acid Characteristics

    PubMed Central

    He, Liyan; Han, Xiaotian; Yu, Zhiming

    2014-01-01

    A rare Phaeodactylum tricornutum cruciform morphotype was obtained and stabilized with a proportion of more than 31.3% in L1 medium and is reported for the first time. Long-term culture and observation showed that the cruciform morphotype was capable of transforming to the oval form following the degeneration of arms by two processes. After three months of culture, four morphotypes existed in a relatively stable proportion in culture for six months (10.5% for oval, 11.3% for fusiform, 37.2% for triradiate and 41.0% for cruciform). Low temperature was particularly beneficial for cruciform cell formation. As the culture temperature decreased from 25C to 10C, the percentage of the cruciform morphotype increased from 39.1% to 55.3% approximately. The abundant cruciform cells endowed this strain with unique fatty acid characteristics. The strain cultured at 15C showed both maximum content of neutral lipid in a single cell and total yield. The maximum content of fatty acid methyl esters was C16:1 for Phaeodactylum tricornutum cultured at four temperatures (43.82% to 50.82%), followed by C16:0 (20.47% to 22.65%). Unique fatty acid composition endowed this strain with excellent quality for biodiesel production. PMID:24710200

  3. Lipoxygenase-catalyzed transformation of epoxy fatty acids to hydroxy-endoperoxides: a potential P450 and lipoxygenase interaction.

    PubMed

    Teder, Tarvi; Boeglin, William E; Brash, Alan R

    2014-12-01

    Herein, we characterize a generally applicable transformation of fatty acid epoxides by lipoxygenase (LOX) enzymes that results in the formation of a five-membered endoperoxide ring in the end product. We demonstrated this transformation using soybean LOX-1 in the metabolism of 15,16-epoxy-?-linolenic acid, and murine platelet-type 12-LOX and human 15-LOX-1 in the metabolism of 14,15-epoxyeicosatrienoic acid (14,15-EET). A detailed examination of the transformation of the two enantiomers of 15,16-epoxy-?-linolenic acid by soybean LOX-1 revealed that the expected primary product, a 13S-hydroperoxy-15,16-epoxide, underwent a nonenzymatic transformation in buffer into a new derivative that was purified by HPLC and identified by UV, LC-MS, and H-NMR as a 13,15-endoperoxy-16-hydroxy-octadeca-9,11-dienoic acid. The configuration of the endoperoxide (cis or trans side chains) depended on the steric relationship of the new hydroperoxy moiety to the enantiomeric configuration of the fatty acid epoxide. The reaction mechanism involves intramolecular nucleophilic substitution (SNi) between the hydroperoxy (nucleophile) and epoxy group (electrophile). Equivalent transformations were documented in metabolism of the enantiomers of 14,15-EET by the two mammalian LOX enzymes, 15-LOX-1 and platelet-type 12-LOX. We conclude that this type of transformation could occur naturally with the co-occurrence of LOX and cytochrome P450 or peroxygenase enzymes, and it could also contribute to the complexity of products formed in the autoxidation reactions of polyunsaturated fatty acids. PMID:25293588

  4. Predicting the fatty acid composition of milk: a comparison of two Fourier transform infrared sampling techniques.

    PubMed

    Afseth, Nils Kristian; Martens, Harald; Randby, Ashild; Gidskehaug, Lars; Narum, Bjrg; Jrgensen, Kjetil; Lien, Sigbjrn; Kohler, Achim

    2010-07-01

    In the present study a novel approach for Fourier transform infrared (FT-IR) characterization of the fatty acid composition of milk based on dried film measurements has been presented and compared to a standard FT-IR approach based on liquid milk measurements. Two hundred and sixty-two (262) milk samples were obtained from a feeding experiment, and the samples were measured with FT-IR as dried films as well as liquid samples. Calibrations against the most abundant fatty acids, CLA (i.e., 18:2cis-9, trans-11), 18:3cis-9, cis-12, cis-15, and summed fatty acid parameters were obtained for both approaches. The estimation errors obtained in the dried film calibrations were overall lower than the corresponding liquid sample calibrations. Similar and good calibrations (i.e., R(2) ranges from 0.82 to 0.94 (liquid samples) and from 0.88 to 0.97 (dried films)) for short-chain fatty acids (6:0-14:0), 18:1cis-9, SAT, MUFA, and iodine value were obtained by both approaches. However, the dried film approach was the only approach for which feasible calibrations (i.e., R(2) ranges from 0.78 to 0.93) were obtained for the major saturated fatty acids 16:0 and 18:0, the minor fatty acid features 4:0, CLA (i.e., 18:2cis-9, trans-11), PUFA, and the summed 18:1 trans isomers. For the dried film approach, logical spectral features were found to dominate the respective fatty acid calibration models. The preconcentration step of the dried film approach could be expected to account for a major part of the prediction improvements going from predictions in liquid milk to predictions in dried films. The dried film approach has a significant potential for use in high-throughput applications in industrial environments and might also serve as a valuable supplement for determination of genetic and breeding factors within research communities. PMID:20615281

  5. Determination of acid number and base number in lubricants by Fourier transform infrared spectroscopy.

    PubMed

    van de Voort, F R; Sedman, J; Yaylayan, V; Saint Laurent, C

    2003-11-01

    This paper describes the development of practical Fourier transform infrared (FT-IR) methods for the determination of acid number (AN) and base number (BN) in lubricants through the combined use of signal transduction via stoichiometric reactions and differential spectroscopy to circumvent matrix effects. Trifluoroacetic acid and potassium phthalimide were used as stoichiometric reactants to provide infrared (IR) signals proportional to the basic and acidic constituents present in oils. Samples were initially diluted with 1-propanol, then split, with one half treated with the stoichiometric reactant and the other half with a blank reagent, their spectra collected, and a differential spectrum obtained to ratio out the invariant spectral contributions from the sample. Quantitation for AN and BN was based on measurement of the peak height of the v(C = O) or v(COO) absorptions, respectively, of the products of the corresponding stoichiometric reactions, yielding a standard error of calibration of < 0.1 mg KOH/g oil. The AN/BN FT-IR methods were validated by the analysis of a wide range of new and used oils supplied by third parties, which had been analyzed by ASTM methods. Good correlations were obtained between the chemical and FT-IR methods, indicating that the measures are on the whole comparable. From a practical perspective, these new FT-IR methods have significant advantages over ASTM titrimetric methods in terms of environmental considerations, sample size, and speed of analysis, as well as the variety of oil types that can be handled. FT-IR analysis combining stoichiometric signal transduction with differential spectroscopy may be of wider utility as an alternative to titration in the determination of acid or basic constituents in complex nonaqueous systems. PMID:14658158

  6. Small interfering ribonucleic acid induces liquid-to-ripple phase transformation in a phospholipid membrane

    NASA Astrophysics Data System (ADS)

    Choubey, Amit; Nomura, Ken-ichi; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya

    2014-09-01

    Small interfering ribonucleic acid (siRNA) molecules play a pivotal role in silencing gene expression via the RNA interference mechanism. A key limitation to the widespread implementation of siRNA therapeutics is the difficulty of delivering siRNA-based drugs to cells. Here, we examine changes in the structure and dynamics of a dipalmitoylphosphatidylcholine bilayer in the presence of a siRNA molecule and mechanical barriers to siRNA transfection in the bilayer. Our all-atom molecular dynamics simulation shows that siRNA induces a liquid crystalline-to-ripple phase transformation in the bilayer. The ripple phase consists of a major region of non-interdigitated and a minor region of interdigitated lipid molecules with an intervening kink. In the ripple phase, hydrocarbon chains of lipid molecules have large compressive stresses, which present a considerable barrier to siRNA transfection.

  7. Identification Of Fatty Acid Isomers By Gas Chromatography / Matrix Isolation / Fourier Transform Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Mossoba, Magdi M.; McDonald, Richard E.; Chen, Jo-Yun T.; Page, Samuel W.

    1989-12-01

    Geometric and positional isomers of fatty acid methyl esters (FAME) derived from hydrogenated soybean oil and margarines were separated by silver nitrate-thin layer chromatography (AgNO3-TLC) followed by capillary gas chromatography (GC) and identified by matrix isolation / Fourier transform infrared (MI/FTIR) spectroscopyi,2. Because of the high specificity of the MI technique, it was possible to distinguish between different 18-carbon aliphatic chains of FAME positional isomers with cis or trans configuration, and to determine their degree of unsaturation. For the first time mid-IR spectra were observed for methylene-interrupted or isolated trans, trans or cis/ trans C18 FAME positional isomers. These spectra could be readily differentiated based on unique MI/FTIR spectral characteristics.

  8. Small interfering ribonucleic acid induces liquid-to-ripple phase transformation in a phospholipid membrane

    SciTech Connect

    Choubey, Amit; Nomura, Ken-ichi; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya

    2014-09-15

    Small interfering ribonucleic acid (siRNA) molecules play a pivotal role in silencing gene expression via the RNA interference mechanism. A key limitation to the widespread implementation of siRNA therapeutics is the difficulty of delivering siRNA-based drugs to cells. Here, we examine changes in the structure and dynamics of a dipalmitoylphosphatidylcholine bilayer in the presence of a siRNA molecule and mechanical barriers to siRNA transfection in the bilayer. Our all-atom molecular dynamics simulation shows that siRNA induces a liquid crystalline-to-ripple phase transformation in the bilayer. The ripple phase consists of a major region of non-interdigitated and a minor region of interdigitated lipid molecules with an intervening kink. In the ripple phase, hydrocarbon chains of lipid molecules have large compressive stresses, which present a considerable barrier to siRNA transfection.

  9. Gold-Catalyzed Reductive Transformation of Nitro Compounds Using Formic Acid: Mild, Efficient, and Versatile.

    PubMed

    Yu, Lei; Zhang, Qi; Li, Shu-Shuang; Huang, Jun; Liu, Yong-Mei; He, He-Yong; Cao, Yong

    2015-09-21

    Developing new efficient catalytic systems to convert abundant and renewable feedstocks into valuable products in a compact, flexible, and target-specific manner is of high importance in modern synthetic chemistry. Here, we describe a versatile set of mild catalytic conditions utilizing a single gold-based solid catalyst that enables the direct and additive-free preparation of four distinct and important amine derivatives (amines, formamides, benzimidazoles, and dimethlyated amines) from readily available formic acid (FA) and nitro starting materials with high level of chemoselectivity. By controlling the stoichiometry of the employed FA, which has attracted considerable interest in the area of sustainable chemistry because of its potential as an entirely renewable hydrogen carrier and as a versatile C1 source, a facile atom- and step-efficient transformation of nitro compounds can be realized in a modular fashion. PMID:26224033

  10. Synthesis, calorimetric, structural and conductivity studies in a new thallium selenate tellurate adduct compound

    SciTech Connect

    Ktari, L.; Abdelhedi, M.; Bouhlel, N.; Dammak, M.; Cousson, A.

    2009-08-05

    The crystal structure of the thallium selenate tellurate Tl{sub 2}SeO{sub 4}.Te(OH){sub 6} (TlSeTe) was determined by X-ray diffraction method. The title compound crystallizes in the monoclinic system with P2{sub 1}/c space group. The following parameters are: a = 12.358(3) A; b = 7.231(1) A; c = 11.986(2) A; {beta} = 111.092(2){sup o}; Z = 4. The structure can be regarded as being built of isolated TeO{sub 6} octahedra and SeO{sub 4} tetrahedra. The Tl{sup +} cations are intercalated between these kinds of polyhedra. The main feature of this structure is the coexistence of two different and independent anions (SeO{sub 4}{sup 2-} and TeO{sub 6}{sup 6-}) in the same unit cell. The structure is stable due to O-H...O hydrogen bonds which link tetrahedral and octahedral groups. Crystals of Tl{sub 2}SeO{sub 4}.Te(OH){sub 6} undergo three endothermal transitions at 373, 395 and 437 K. These transitions are detected by DSC and analyzed by dielectric measurements with impedance spectroscopy. The evolution of conductivity versus temperature showed the presence of a protonic conduction phase transition at 437 K. The phase transition at 373 K can be related to a structural phase transition, whereas the one at 395 K is ascribed as likely due to a ferroelectric-paraelectric phase transition.

  11. Prediction of valid acidity in intact apples with Fourier transform near infrared spectroscopy*

    PubMed Central

    Liu, Yan-de; Ying, Yi-bin; Fu, Xia-ping

    2005-01-01

    To develop nondestructive acidity prediction for intact Fuji apples, the potential of Fourier transform near infrared (FT-NIR) method with fiber optics in interactance mode was investigated. Interactance in the 800 nm to 2619 nm region was measured for intact apples, harvested from early to late maturity stages. Spectral data were analyzed by two multivariate calibration techniques including partial least squares (PLS) and principal component regression (PCR) methods. A total of 120 Fuji apples were tested and 80 of them were used to form a calibration data set. The influences of different data preprocessing and spectra treatments were also quantified. Calibration models based on smoothing spectra were slightly worse than that based on derivative spectra, and the best result was obtained when the segment length was 5 nm and the gap size was 10 points. Depending on data preprocessing and PLS method, the best prediction model yielded correlation coefficient of determination (r 2) of 0.759, low root mean square error of prediction (RMSEP) of 0.0677, low root mean square error of calibration (RMSEC) of 0.0562. The results indicated the feasibility of FT-NIR spectral analysis for predicting apple valid acidity in a nondestructive way. PMID:15682498

  12. Transformation and Deoxyribonucleic Acid Size: Extent of Degradation on Entry Varies with Size of Donor

    PubMed Central

    Morrison, D. A.; Guild, W. R.

    1972-01-01

    The fate of label introduced as donor deoxyribonucleic acid (DNA) into competent cells of Diplococcus pneumoniae was determined immediately after entry at 25 C, as a function of the size of the donor DNA. Part of the label is found to be acid soluble, part has been incorporated into chromosomal DNA, apparently through reincorporation of degraded donor DNA, and part is found in single strands of length smaller than that of the input donor DNA strands. The last fraction apparently constitutes the precursor for integration of intact donor genetic markers and is referred to as the intact fraction. For large donor DNA the intact fraction contains over 80% of the total intracellular label, but the median strand length has been reduced to 2.2 × 106 daltons. For small donor molecules (1 × 105 to 6 × 105 daltons per strand) the fraction intact increases with donor size from 10 to 50% of the total intracellular label, and the median strand length of this fraction is half that of the donor strands. By combining these results with earlier data on the size dependence of the yield of transformants per unit of total intracellular donor label, we have calculated the probability that a marker in the intact fraction will be integrated, as a function of the length of the donor strand after entry. This probability has a linear dependence on strand length for activities below 40% of maximum, and extrapolates to zero activity at 77,000 daltons per strand. PMID:4404818

  13. A Single Enzyme Transforms a Carboxylic Acid into a Nitrile through an Amide Intermediate.

    PubMed

    Nelp, Micah T; Bandarian, Vahe

    2015-09-01

    The biosynthesis of nitriles is known to occur through specialized pathways involving multiple enzymes; however, in bacterial and archeal biosynthesis of 7-deazapurines, a single enzyme, ToyM, catalyzes the conversion of the carboxylic acid containing 7-carboxy-7-deazaguanine (CDG) into its corresponding nitrile, 7-cyano-7-deazaguanine (preQ0 ). The mechanism of this unusual direct transformation was shown to proceed via the adenylation of CDG, which activates it to form the newly discovered amide intermediate 7-amido-7-deazaguanine (ADG). This is subsequently dehydrated to form the nitrile in a process that consumes a second equivalent of ATP. The authentic amide intermediate is shown to be chemically and kinetically competent. The ability of ToyM to activate two different substrates, an acid and an amide, accounts for this unprecedented one-enzyme catalysis of nitrile synthesis, and the differential rates of these two half reactions suggest that this catalytic ability is derived from an amide synthetase that gained a new function. PMID:26228534

  14. Surface complexation of mellitic acid to goethite: an attenuated total reflection Fourier transform infrared study.

    PubMed

    Johnson, Bruce B; Sjberg, Staffan; Persson, Per

    2004-02-01

    The nature of the interaction between mellitic acid (benzene hexacarboxylic acid) and the common soil mineral goethite (alpha-FeOOH) has been investigated as a function of pH and ionic strength by use of attenuated total reflection Fourier transform infrared spectroscopy. Molecular orbital calculations of the theoretical vibrational frequencies of the mellitate ion (L6-) and dihydrogen mellitate (H2L4-) have allowed the measured absorption frequencies to be accurately assigned. At pH values above 6, adsorption involves outer-sphere complexation of the deprotonated L6- ion. At lower pH values, there is evidence of a second outer-sphere surface complex involving a partially protonated species, although the extent of protonation of the surface species is significantly less than that found for the solution species at the same pH. While there is no evidence of inner-sphere complexation, increasing the ionic strength to 2.0 M does not displace the adsorbed species but does increase the fraction present on the surface as the fully deprotonated L6-. The small effect of ionic strength suggests that the adsorptive interaction, although outer-sphere in character, is still relatively strong, which indicates that hydrogen bonds may play a significant role. Hydrogen bonding may also help to account for the observed outer-sphere complexation at pH values above the pHiep of goethite. PMID:15773110

  15. Qualitative determination of ?-acids and their transformation products in beer and hop using HR/AM-LC-MS/MS.

    PubMed

    Duek, Martin; Olovsk, Jana; Krofta, Karel; Jurkov, Marie; Mikyka, Alexandr

    2014-08-01

    Hops represent an important source of ?-acids with antimicrobial and sensory properties. Transformation products of ?-acids formed during their oxidation, mainly hulupones, have been shown to have an interesting kind of bitterness. Their structures were recently elucidated using LC-TOFMS and 1D/2D NMR in solution after thermal treatment of the hop ?-acids. This study demonstrates the advantages of MS detection with high resolution and accurate mass measurements. The structure of transformation products in an experimental solution of oxidized ?-acids was elucidated using a newly developed method by hybrid quadrupole-Orbitrap MS. In addition to already known structures, two new ones were identified and named epoxycohulupone and epoxyhulupone. The method was verified on real samples; the profiles of these products in Sldek hops harvested in 2008 and 2012 and in corresponding beers were compared. For this purpose, a new QuEChERS assay was used for the preparation of beer samples. PMID:25099125

  16. Fourier transform infrared spectroscopy and differential scanning calorimetry studies of fatty acid homogeneous ceramide 2.

    PubMed

    Chen, H; Mendelsohn, R; Rerek, M E; Moore, D J

    2000-09-29

    Ceramides provide a major component of the barrier function of skin. An understanding of barrier organization requires a detailed characterization of ceramide phase behavior and molecular interactions. Toward this end, Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) studies of ceramide 2 analogues (non-hydroxylated fatty acid N-acyl sphingosines) of specific chain lengths (C(14), C(16), C(18), C(20)) are presented. In addition, the molecular interactions of the individual chains in each molecule are elucidated through thermotropic FTIR studies of derivatives possessing perdeuterated fatty acid chains. DSC data showed a much smaller chain length variation (for the C(16), C(18), C(20) derivatives) in the main order-disorder transition temperature (approx. 93+/-1 degrees C) than is observed in the corresponding series of phosphatidylcholines, consistent with minimal ceramide hydration. The temperature dependence of the methylene stretching and scissoring modes revealed a solid-solid phase transition at 20-25 degrees C below the main order-disorder transition accompanied by chain packing alterations from orthorhombic-->hexagonal subcells. The chain packing transition was accompanied by enhanced penetration of water into the polar region. This was deduced from the temperature dependence of the amide I and II modes, which provide direct evidence for H-->D exchange. The CD(2) scissoring mode splitting of the deuterated fatty acid constituent of the C(16), C(18), C(20) chains revealed preferential segregation of microdomains (3-5 chains) of this species within the orthorhombic phase. In contrast, the sphingosine base chains appeared to be sufficiently separated so as to inhibit interchain vibrational coupling between them. FTIR spectroscopy provides a convenient means for characterizing domain formation, chain packing, and hydration sites of these phases, which are highly ordered under physiological conditions. PMID:11018673

  17. Tellurite-, tellurate-, and selenite-based anaerobic respiration by strain CM-3 isolated from gold mine tailings.

    PubMed

    Maltman, Chris; Piercey-Normore, Michele D; Yurkov, Vladimir

    2015-09-01

    The newly discovered strain CM-3, a Gram-negative, rod-shaped bacterium from gold mine tailings of the Central Mine in Nopiming Provincial Park, Canada, is capable of dissimilatory anaerobic reduction of tellurite, tellurate, and selenite. CM-3 possesses very high level resistance to these oxides, both aerobically and anaerobically. During aerobic growth, tellurite and tellurate resistance was up to 1500 and 1000 µg/ml, respectively. In the presence of selenite, growth occurred at the highest concentration tested, 7000 µg/ml. Under anaerobic conditions, resistance was decreased to 800 µg/ml for the Te oxides; however, much like under aerobic conditions, growth with selenite still took place at 7000 µg/ml. In the absence of oxygen, CM-3 couples oxide reduction to an increase in biomass. Following an initial drop in viable cells, due to switching from aerobic to anaerobic conditions, there was an increase in CFU/ml greater than one order of magnitude in the presence of tellurite (6.6 × 10(3)-8.6 × 10(4) CFU/ml), tellurate (4.6 × 10(3)-1.4 × 10(5) CFU/ml), and selenite (2.7 × 10(5)-5.6 × 10(6) CFU/ml). A control culture without metalloid oxides showed a steady decrease in CFU/ml with no recovery. ATP production was also increased in the presence of each oxide, further indicating anaerobic respiration. Partial 16S rRNA gene sequencing revealed a 99.0 % similarity of CM-3 to Pseudomonas reactans. PMID:26254805

  18. Fourier transform infrared study on hydrogen bonding species of carboxylic acids in supercritical carbon dioxide with ethanol

    SciTech Connect

    Yamamoto, Morio; Iwai, Yoshio; Nakajima, Taro; Arai, Yasuhiko

    1999-05-06

    Supercritical fluid extraction has been given much attention recently as one of the new separation technologies in the chemical industry. Fourier transform infrared (FTIR) spectroscopy has been used to determine the equilibrium constants of the dimerization for carboxylic acid (acetic acid or palmitic acid) and the amount of hydrogen bonding species between carboxylic acid and ethanol in supercritical CO{sub 2}. Experiments were carried out at 308.2--313.2 K and 10.0--20.0 MPa. The noticeable band was the C{double_bond}O stretching band for carboxylic acid. In the binary system (supercritical CO{sub 2} + carboxylic acid), the equilibrium constants of the dimerization between the carboxylic acid monomer and dimer decrease with increasing pressure and temperature. The equilibrium constants of palmitic acid are larger than those of acetic acid. In a ternary system (supercritical CO{sub 2} + carboxylic acid + ethanol), the amount of hydrogen bonding species between carboxylic acid and ethanol in supercritical CO{sub 2} increases with the increasing mole fraction of added ethanol. Furthermore, the authors confirm that the solubility enhancement by ethanol used as an entrainer in supercritical CO{sub 2} related to the amount of hydrogen bonding species between carboxylic acid and ethanol.

  19. Process Coupling Between Mineral Transformation and U Speciation in Acid Waste Weathered Sediments

    NASA Astrophysics Data System (ADS)

    Perdrial, N.; Kanematsu, M.; Wang, G.; Um, W.; O'Day, P. A.; Chorover, J.

    2013-12-01

    The need for better prediction of contaminant transport motivates multi-faceted lines of inquiry to build a strong bridge between molecular- and field-scale information. At Hanford (WA), millions of liters of U-containing acidic wastes have been discharged to the soil. In order to predict reactive contaminant migration in the soil, it is necessary to determine the process coupling that occurs between mineral transformation and uranium speciation in these acid-uranium waste weathered sediments. Furthermore, we seek to establish linkages between molecular-scale contaminant speciation and meso-scale contaminant lability, release and reactive transport. Unweathered Hanford sediments were reacted for 365 days with acidic (pH 3), uranium bearing waste solutions in batch experiments. The presence and absence of phosphate in the waste as a control on uranium speciation was also investigated. At dedicated reaction times (7, 14, 30, 90, 180 and 365 days) solid and solution chemistry were analyzed to determine weathering trajectories and contaminant speciation. As observed by XRD and U-EXAFS, when present, PO4 exerted a strong controls over uranium speciation at all pH with the rapid precipitation of meta-ankoleite [K(UO2PO4).3H2O] and near complete immobilization of U. Over prolonged reaction time, however, small fractions of boltwoodite [K(UO2)(HSiO4).3H2O] increased in PO4-high U systems. When PO4 was excluded from the reaction systems, U speciation was indirectly controlled by the pH of the reactant solution and its effect on primary mineral weathering. In this case, U immobilization remained limited with 25 to 50% of the uranium precipitated as becquerelite ([Ca(UO2)6O4(OH)6.3H2O] or the K equivalent - compreignacite) and suspected boltwoodite. Differences between the systems are attributed to process coupling between acid chemistry and U geochemistry. Carbonate weathering contributed to rapidly buffer the pH to pH 7-8 in the absence of PO4 and to 6-7 in its presence, promoting subsequent silicate weathering that makes aqueous Si available for boltwoodite precipitation. Comparison with homogeneous nucleation experiments and thermodynamic calculations confirmed the strong phosphate control over U speciation and the multispeciation of U in its absence.

  20. Nordihydroguaiaretic acid inhibits transforming growth factor beta type 1 receptor activity and downstream signaling.

    PubMed

    Li, Fusheng; Pham, Johnny D; Anderson, Marc O; Youngren, Jack F

    2009-08-15

    It has been well documented that nordihydroguaiaretic acid (NDGA), a phenolic lignan isolated from the creosote bush, Larrea tridentate, has anti-cancer activity in vitro and in vivo. Several mechanisms have been identified that could contribute to these actions, as NDGA directly inhibits metabolic enzymes and receptor tyrosine kinases that are established anti-cancer targets. In the present study, we show that NDGA inhibits the transforming growth factor beta (TGF-beta) type I receptor, a serine threonine kinase receptor. In cultured cells, NDGA treatment repressed Smad2 phosphorylation induced by TGF-beta treatment and by a constitutively active mutant of TGF-beta type I receptor (T202D). NDGA also inhibited downstream transcriptional activation mediated by both TGF-beta treatment and the constitutively active mutant receptor. In vitro, NDGA inhibited TGF-beta type I receptor mediated Smad2 phosphorylation in crude cell lysates and in a purified preparation. Importantly, screening select analogs demonstrated that modification of NDGA's structure resulted in altered potency against the receptor. These results indicated that the structure of NDGA can be modified to achieve increased potency. Together our data provide a novel mechanism for NDGA activity which could help explain its anti-cancer activity, and suggest that NDGA could serve as a structural motif for developing serine/threonine kinase inhibitors with selectivity for TGF-beta type I receptor. PMID:19540220

  1. Nordihydroguaiaretic acid inhibits transforming growth factor β type 1 receptor activity and downstream signaling

    PubMed Central

    Li, Fusheng; Anderson, Marc O.; Youngren, Jack F.

    2009-01-01

    It has been well documented that nordihydroguaiaretic acid (NDGA), a phenolic lignan isolated from the creosote bush, Larrea tridentate, has anti-cancer activity in vitro and in vivo. Several mechanisms have been identified that could contribute to these actions, as NDGA directly inhibits metabolic enzymes and receptor tyrosine kinases that are established anti-cancer targets. In the present study, we show that NDGA inhibits the transforming growth factor β (TGF-β) type I receptor, a serine threonine kinase receptor. In cultured cells, NDGA treatment repressed Smad2 phosphorylation induced by TGF-β treatment and by a constitutively active mutant of TGF-β type I receptor (T202D). NDGA also inhibited downstream transcriptional activation mediated by both TGF-β treatment and the constitutively active mutant receptor. In vitro, NDGA inhibited TGF-β type I receptor mediated Smad2 phosphorylation in crude cell lysates and in a purified preparation. Importantly, screening select analogs demonstrated that modification of NDGA’s structure resulted in altered potency against the receptor. These results indicated that the structure of NDGA can be modified to achieve increased potency. Together our data provide a novel mechanism for NDGA activity which could help explain its anti-cancer activity, and suggest that NDGA could serve as a structural motif for developing serine/threonine kinase inhibitors with selectivity for TGF-β type I receptor. PMID:19540220

  2. Experimental in situ transformation of Pb smelter fly ash in acidic soils.

    PubMed

    Ettler, Vojtěch; Mihaljevič, Martin; Sebek, Ondřej; Matys Grygar, Tomáš; Klementová, Mariana

    2012-10-01

    Soils in the vicinity of nonferrous metal smelters are often highly polluted by inorganic contaminants released from particulate emissions. We used a technique with double polyamide experimental bags (1-μm mesh) to study the in situ transformation of fly ash (FA) from a secondary Pb smelter in acidic soil profiles. Between 62 and 66% of the FA dissolved after one year's exposure in the soils, leading to complete dissolution of primary caracolite (Na(3)Pb(2)(SO(4))(3)Cl) and KPb(2)Cl(5), with formation of secondary anglesite (PbSO(4)), minor PbSO(3), and trace carbonates. Release of Pb was pH-dependent, whereas not for Cd and Zn. Significant amounts of metals (mainly Cd and Zn) partitioned into labile soil fractions. The field data agreed with laboratory pH-static leaching tests performed on FA, which was washed before the experiment to remove soluble salts. This indicates that appropriate laboratory leaching can accurately predict FA behavior in real-life scenarios (e.g., exposure in soil). PMID:22938623

  3. Fourier Transform Infrared (FTIR) Spectroscopy as a Utilitarian Tool for the Routine Determination of Acidity in Ester-Based Oils.

    PubMed

    Meng, Xianghe; Li, Lei; Ye, Qin; van de Voort, Frederik

    2015-09-23

    A primary Fourier transform infrared (FTIR) method capable of determining acidity in ester-based oils is described and evaluated. Absolute free fatty acid (%FFA) and acid value (AV) calibrations were devised by spiking oleic acid into a refined, acid-free oil and measuring ? COO(-) at ? 1569 and ? phenolate(-) at ? 1588 cm(-1), respectively, in the second-derivative differential spectra. The FTIR acidity predictions were compared to the AOCS titrimetric method using acid mixtures as well as acid containing used vendor oils of undefined makeup and provenance, using two spectroscopically divergent reference oils as AC0. Relative to the AOCS reference method, the FTIR procedure was found to be both more accurate ( 0.107 vs 0.122) and reproducible ( 0.025 vs 0.077) in determining %FFA and similar in predicting AV. The FTIR phenolate method overcomes a variety of limitations of earlier FTIR-based methods, being particularly simple and well suited to routine, semiautomated acidity analysis of ester-based oils using a basic FTIR spectrometer. PMID:26321291

  4. Amino acids in the Pearl River Estuary and adjacent waters: origins, transformation and degradation

    NASA Astrophysics Data System (ADS)

    Chen, Jianfang; Li, Yan; Yin, Kedong; Jin, Haiyan

    2004-10-01

    Two cruises were conducted in the Pearl River Estuary (PRE) and adjacent coastal waters during July 1999 and 2000 to investigate spatial variation, transformation and degradation of amino acids (AAs). Salinity, suspended sediments (SS), chl a, nutrients, dissolved organic carbon, particulate organic carbon, AAs, and hexosamines were measured and analyzed. Concentrations of particulate hydrolysable AAs (PHAAs), dissolved combined AAs and dissolved free AAs ranged from 0.41 to 12.6 ?mol L-1, 1.1 to 4.0 ?mol L-1 and 0.15 to 1.10 ?mol L-1, respectively. AAs concentrations were low in waters of salinity <10, increased to the maximum in the estuarine and coastal plumes (salinity =10-25) and decreased beyond the coastal plume. There was a region where PHAAs were maximum, which coincided with the region of the chl a maximum and depletion of dissolved inorganic phosphorus in the coastal plume south of Hong Kong. This indicates that most of the AAs in estuarine and coastal waters were produced through phytoplankton production and AAs might be a temporary sink for inorganic nitrogen. The ratios of AAs/HAs and glucosamine/galactosamine (Glc-NH2/Gal-NH2) were on average, 26.0 and 3.8, respectively, in biogenic particulate matter (chl a >5 ?g L-1 and SS<10 mg L-1), decreased in turbid particles (SS>20 mg L-1) and reached the lowest values of 5.8 and 1.4 in sediments. In particular, the ratios of AAs/HAs, Glc-NH2/Gal-NH2 were low in the upper or northwest side of the estuary where turbidity was high. This indicated that these AAs were "old", likely due to resuspension of refractory organic matter from sediments or zooplankton grazing modification and bacterial reworking as the salt wedge advanced upstream near the bottom. Apparently, the dynamics of AAs in the PRE appeared to be governed by biological production processes and estuarine circulation in the estuary. As the chl a maximum developed downstream in the estuarine and coastal plume and the salt wedge moved upstream at the bottom, AAs increased and were subjected to sinking as particulates, grazing by zooplankton and reworking by bacterial activity. Sinking AAs would be transformed and modified in the lower layer, which would be brought back into the estuary in the salt wedge during the estuarine circulation.

  5. Transformation of salvianolic acid B to salvianolic acid a in aqueous solution and the in vitro liver protective effect of the main products.

    PubMed

    Kan, Shidong; Chen, Zhouzhou; Shao, Lei; Li, Ji'an

    2014-04-01

    Salvianolic acid A (Sal A) was considered to be the compound with highest activity in Salvia miltiorrhiza (danshen). Due to its low content in raw materials, many studies reported its preparation from salvianolic acid B (Sal B). However, the process of this transformation is still unknown. Our objective was to find the chemical change of the transformation from Sal B to Sal A. The results showed that Sal B was hydrolyzed to lithospermic acid (LA) first, and the latter was transformed into Sal A in thermal aqueous solution. The radical scavenging ability of Sal A, Sal B, and LA was tested through DPPH, and Sal A showed higher radical elimination ability compared to Sal B and LA. In vitro liver damage was induced by CCl4 in human hepatic WRL68 cell line. Sal A, Sal B, and LA showed liver protective ability in a dose-dependent manner, while Sal A possessed a much higher ability compared to Sal B and LA. PMID:24689808

  6. Insights into the Role of Humic Acid on Pd-catalytic Electro-Fenton Transformation of Toluene in Groundwater

    NASA Astrophysics Data System (ADS)

    Liao, Peng; Al-Ani, Yasir; Malik Ismael, Zainab; Wu, Xiaohui

    2015-03-01

    A recently developed Pd-based electro-Fenton (E-Fenton) process enables efficient in situ remediation of organic contaminants in groundwater. In the process, H2O2, Fe(II), and acidic conditions (~pH 3) are produced in situ to facilitate the decontamination, but the role of ubiquitous natural organic matters (NOM) remain unclear. This study investigated the effect of Aldrich humic acid (HA) on the transformation of toluene by the Pd-based E-Fenton process. At pH 3 with 50 mA current, the presence of HA promoted the efficiency of toluene transformation, with pseudo-first-order rate constants increase from 0.01 to 0.016 as the HA concentration increases from 0 to 20 mg/L. The HA-enhanced toluene transformation was attributed to the accelerated thermal reduction of Fe(III) to Fe(II), which led to production of more hydroxyl radicals. The correlation of the rate constants of toluene transformation and HA decomposition validated hydroxyl radical (.OH) as the predominant reactive species for HA decomposition. The finding of this study highlighted that application of the novel Pd-based E-Fenton process in groundwater remediation may not be concerned by the fouling from humic substances.

  7. Insights into the Role of Humic Acid on Pd-catalytic Electro-Fenton Transformation of Toluene in Groundwater

    PubMed Central

    Liao, Peng; Al-Ani, Yasir; Malik Ismael, Zainab; Wu, Xiaohui

    2015-01-01

    A recently developed Pd-based electro-Fenton (E-Fenton) process enables efficient in situ remediation of organic contaminants in groundwater. In the process, H2O2, Fe(II), and acidic conditions (~pH 3) are produced in situ to facilitate the decontamination, but the role of ubiquitous natural organic matters (NOM) remain unclear. This study investigated the effect of Aldrich humic acid (HA) on the transformation of toluene by the Pd-based E-Fenton process. At pH 3 with 50?mA current, the presence of HA promoted the efficiency of toluene transformation, with pseudo-first-order rate constants increase from 0.01 to 0.016 as the HA concentration increases from 0 to 20?mg/L. The HA-enhanced toluene transformation was attributed to the accelerated thermal reduction of Fe(III) to Fe(II), which led to production of more hydroxyl radicals. The correlation of the rate constants of toluene transformation and HA decomposition validated hydroxyl radical (OH) as the predominant reactive species for HA decomposition. The finding of this study highlighted that application of the novel Pd-based E-Fenton process in groundwater remediation may not be concerned by the fouling from humic substances. PMID:25783864

  8. State of the art of Lewis acid-containing zeolites: lessons from fine chemistry to new biomass transformation processes.

    PubMed

    Moliner, Manuel

    2014-03-21

    The former synthesis of TS-1 opened new catalytic opportunities for zeolites, especially for their application as selective redox catalysts in several fine chemistry processes. Interestingly, isolated Ti species in the framework positions of hydrophobic zeolites, such as high silica zeolites, offer unique Lewis acid sites even in the presence of protic polar solvents (such as water). Following this discovery, other transition metals (such as Sn, Zr, V, Nb, among others) have been introduced in the framework positions of different hydrophobic zeolitic structures, allowing their application in new fine chemistry processes as very active and selective redox catalysts. Recently, these hydrophobic metallozeolites have been successfully applied as efficient catalysts for several biomass-transformation processes in bulk water. The acquired knowledge from the former catalytic descriptions in fine chemistry processes using hydrophobic Lewis acid-containing zeolites has been essential for their application in these novel biomass transformations. In the present review, I will describe the recent advances in the synthesis of new transition metal-containing zeolites presenting Lewis acid character, and their unique catalytic applications in both fine chemistry and novel biomass-transformations. PMID:24142026

  9. Deoxyribonucleic acid-mediated gene transfer in mammalian cells: Molecular analysis of unstable transformants and their progression to stability

    SciTech Connect

    Scangos, G.A.; Huttner, K.M.; Juricek, D.K.; Ruddle, F.H.

    1981-02-01

    To elucidate mechanisms involved in deoxyribonucleic acid-mediated gene transfer, we transferred the herpes simplex virus thymidine kinase gene (TK) into mouse Ltk/sup -/ cells. Independent TK/sup +/ clones (transformants) and derivatives of each were tested for phenotypic expression and the presence and arrangement of TK sequences. Initially, transformants expressed viral TK unstably, with 10% of the cells in each generation losing both the TK/sup +/ phenotype and virally derived TK sequences. After a prolonged period in culture, stable subpopulations arose from which the TK/sup +/ phenotype and viral sequence were no longer lost at detectable frequency. Analysis of unstable cell populations indicated that individual viral deoxyribonucleic acid molecules were reduced in size, but were linked to other deoxyribonucleic acid to form molecules large enough to be precipitated in a Hirt fractionation. The authors term these molecules transgenomes. Analysis of independent unstable subclones derived from the primary transformants demonstrated that individual transgenomes could contain multiple copies of the viral TK sequences. Recipient cell lines frequently possesses more than one type of the transgenome and possibly multiple copies per cell of each type. Stable derivatives possesses only one of the transgenomes present in the unstable parent, and these sequences were associated with a recipient cell chromosome.

  10. The study of aluminum loss and consequent phase transformation in heat-treated acid-leached kaolin

    SciTech Connect

    Foo, Choo Thye; Mahmood, Che Seman; Mohd Salleh, Mohamad Amran

    2011-04-15

    This study investigates the effect of Al leaching during Fe removal from kaolin to mullite. Heat-treated kaolin was obtained by heating natural kaolin at 400, 500, 600, 700, 800 and 900 deg. C. The heat-treated kaolin was then leached at 100 deg. C with 4 M, 3 M, 2 M, 1 M, 0.2 M solution of H{sub 2}SO{sub 4} and 0.2 M solution of oxalic acid. The dried samples were sintered to 1300 deg. C for 4 h at a heating rate of 10 deg. C min{sup -1}. X-ray diffractometry and differential thermal analysis were used to study the phase transformation of kaolin to mullite. It was found that 700 deg. C is the optimum preheat-treatment temperature to leach out Fe and also Al for both types of the acids used. The majority of the 4 M sulfuric acid-treated kaolins formed the cristobalite phase when sintered. On the other hand, 1 M, 0.2 M sulfuric acid and 0.2 M oxalic acid leached heat-treated kaolin formed mullite and quartz phase after sintering. - Research Highlights: {yields} Preheat-treatment of kaolin improves the leachability of unwanted iron. {yields} The optimum preheat-treatment temperature is 700 deg. C. {yields} Sintered 4 M sulfuric acid-treated kaolin majorly formed the cristobalite phase. {yields} Sintered 0.2 M oxalic acid-treated kaolin formed lesser amorphous silicate phase.

  11. Qualitative/chiral sensing of amino acids by naked-eye fluorescence change based on morphological transformation and hierarchizing in supramolecular assemblies of pyrene-conjugated glycolipids.

    PubMed

    Kameta, Naohiro; Masuda, Mitsutoshi; Shimizu, Toshimi

    2015-07-14

    Supramolecular assemblies of fluorescent glycolipids exhibited molecular packing rearrangement as well as morphological transformation, in response to amino acid analytes. Naked-eye detectable fluorescence color changes and hydrogel formation as the result of the amplification of the molecular- and nanometer-scaled changes enabled not only qualitative analysis but also chiral sensing of a specific amino acid among 20 amino acids. PMID:26065855

  12. Mass balance and transformation of corn stover by pretreatment with different dilute organic acids.

    PubMed

    Qin, Lei; Liu, Zhi-Hua; Li, Bing-Zhi; Dale, Bruce E; Yuan, Ying-Jin

    2012-05-01

    Previous studies indicated high xylose yield could be achieved after pretreatment using organic acids, but it is necessary to systematically investigate the effects of different parameters during organic acid pretreatments. Corn stover was pretreated with sulfuric, oxalic, citric, tartaric and acetic acid at 50 and 90 mM from 130 to 190C. The xylan balance for each different acid was distinct, but all balances were very close to 100% by determining xylan recovery, xylooligomer yield, xylose yield and furfural yield. The effects of combined severity on the recovery or yields of these components were also studied. The acid pK(a) value affected the proportion of xylan degradation products. The maximum value of xylose and xylooligomer yield for specific acid pretreatment was also determined by pK(a) value. The maximum xylose yield was obtained after pretreatment with sulfuric and oxalic acid, but more xylooligomers were obtained after pretreatment with weaker acids. PMID:22437047

  13. Metformin and phenformin deplete tricarboxylic acid cycle and glycolytic intermediates during cell transformation and NTPs in cancer stem cells.

    PubMed

    Janzer, Andreas; German, Natalie J; Gonzalez-Herrera, Karina N; Asara, John M; Haigis, Marcia C; Struhl, Kevin

    2014-07-22

    Metformin, a first-line diabetes drug linked to cancer prevention in retrospective clinical analyses, inhibits cellular transformation and selectively kills breast cancer stem cells (CSCs). Although a few metabolic effects of metformin and the related biguanide phenformin have been investigated in established cancer cell lines, the global metabolic impact of biguanides during the process of neoplastic transformation and in CSCs is unknown. Here, we use LC/MS/MS metabolomics (>200 metabolites) to assess metabolic changes induced by metformin and phenformin in an Src-inducible model of cellular transformation and in mammosphere-derived breast CSCs. Although phenformin is the more potent biguanide in both systems, the metabolic profiles of these drugs are remarkably similar, although not identical. During the process of cellular transformation, biguanide treatment prevents the boost in glycolytic intermediates at a specific stage of the pathway and coordinately decreases tricarboxylic acid (TCA) cycle intermediates. In contrast, in breast CSCs, biguanides have a modest effect on glycolytic and TCA cycle intermediates, but they strongly deplete nucleotide triphosphates and may impede nucleotide synthesis. These metabolic profiles are consistent with the idea that biguanides inhibit mitochondrial complex 1, but they indicate that their metabolic effects differ depending on the stage of cellular transformation. PMID:25002509

  14. Metformin and phenformin deplete tricarboxylic acid cycle and glycolytic intermediates during cell transformation and NTPs in cancer stem cells

    PubMed Central

    Janzer, Andreas; German, Natalie J.; Gonzalez-Herrera, Karina N.; Asara, John M.; Haigis, Marcia C.; Struhl, Kevin

    2014-01-01

    Metformin, a first-line diabetes drug linked to cancer prevention in retrospective clinical analyses, inhibits cellular transformation and selectively kills breast cancer stem cells (CSCs). Although a few metabolic effects of metformin and the related biguanide phenformin have been investigated in established cancer cell lines, the global metabolic impact of biguanides during the process of neoplastic transformation and in CSCs is unknown. Here, we use LC/MS/MS metabolomics (>200 metabolites) to assess metabolic changes induced by metformin and phenformin in an Src-inducible model of cellular transformation and in mammosphere-derived breast CSCs. Although phenformin is the more potent biguanide in both systems, the metabolic profiles of these drugs are remarkably similar, although not identical. During the process of cellular transformation, biguanide treatment prevents the boost in glycolytic intermediates at a specific stage of the pathway and coordinately decreases tricarboxylic acid (TCA) cycle intermediates. In contrast, in breast CSCs, biguanides have a modest effect on glycolytic and TCA cycle intermediates, but they strongly deplete nucleotide triphosphates and may impede nucleotide synthesis. These metabolic profiles are consistent with the idea that biguanides inhibit mitochondrial complex 1, but they indicate that their metabolic effects differ depending on the stage of cellular transformation. PMID:25002509

  15. Amino acid-dependent transformations of citrate-coated silver nanoparticles: impact on morphology, stability and toxicity.

    PubMed

    Shi, Junpeng; Sun, Xia; Zou, Xiaoyan; Zhang, Hongwu

    2014-08-17

    Humans face the risk of exposure to silver nanoparticles (AgNPs) due to their extensive application in consumer products. AgNPs can interact with many substances in the human body due to their chemically unstable nature and high activity properties, which might result in unknown hazards and even some serious diseases for humans. As the basic constituent element of human bodies, amino acids (AAs) differ in concentration and variety in different cells and tissues. Thus, understanding the transformation of citrate-coated AgNPs in the presence of AAs is crucial for determining their fate and toxicity in the human body. Our study focused on the transformation of the morphology, dissolution behavior and reaction product of AgNPs in different AA-containing systems and then evaluated the effect of these transformations on the cytotoxicity of AgNPs. The obtained results indicated that the addition of glycine with the lowest Ag(+) binding energy had little effect on the transformations and toxicity of AgNPs. While in the presence of histidine with higher Ag(+) binding energy, the Ag(+) release and particle size of AgNPs obviously increased. These transformations resulted in a decrease in the cytotoxicity of AgNPs due to the formation of Ag-His complex and the growth of AgNPs. Furthermore, l-cysteine with the highest Ag(+) binding energy could easily interact with AgNPs, transforming them completely to form [Ag(Cys)n](+) and Ag2S precipitates, which induced the largest decrease in AgNP toxicity. In summary, our results may provide useful information to understand the fate, transformation, and toxicity of citrate-coated AgNPs in the human body. PMID:24910988

  16. ORGANIC ACID DERIVATIZATION TECHNIQUES APPLIED TO PETROLEUM HYDROCARBON TRANSFORMATIONS IN SUBSURFACE ENVIRONMENTS

    EPA Science Inventory

    Evidence for the natural microbial remediation of subsurface fuel contamination situations should include identification and analysis of transformation or degradation products. In this way. u mass balance between fuel constituents and end products may be approached to monitor cle...

  17. ORGANIC ACID DERIVATIZATION TECHNIQUES APPLIED TO PETROLEUM HYDROCARBON TRANSFORMATIONS IN SUBSURFACE ENVIRONMENT

    EPA Science Inventory

    Evidence for the natural microbial remediation of subsurface fuel contamination situations should include identification and analysis of transformation or degradation products. n this way, a mass balance between fuel constituents and end products may be approached to monitor clea...

  18. Thermal transformation of trans-5-O-caffeoylquinic acid (trans-5-CQA) in alcoholic solutions.

    PubMed

    Dawidowicz, Andrzej L; Typek, Rafal

    2015-01-15

    Chlorogenic acid (CQA), the ester of caffeic acid with quinic acid supplied to human organisms mainly with coffee, tea, fruit and vegetables, has been one of the most studied polyphenols. It is potentially useful in pharmaceuticals, food additives, and cosmetics due to its recently discovered biomedical activity, which revived interest in its properties, isomers and natural occurrence. We found that the heating of the alcoholic solution of trans-5-O-caffeoylquinic acid produced at least twenty compounds (chlorogenic acid derivatives and its reaction products with water and alcohol). The formation of three of them (methoxy, ethoxy and propoxy adducts) has not been reported yet. No reports exist either on methoxy adducts of 3- and 4-O-caffeoylquinic acid appearing in buffered methanol/water mixtures at pH exceeding 7. We observed that the amount of each formed component depended on the heating time, type of alcohol, its concentration in alcoholic/water mixture, and pH. PMID:25148959

  19. Transformation of Fatty Acids Catalyzed by Cytochrome P450 Monooxygenase Enzymes of Candida tropicalis

    PubMed Central

    Eschenfeldt, William H.; Zhang, Yeyan; Samaha, Hend; Stols, Lucy; Eirich, L. Dudley; Wilson, C. Ronald; Donnelly, Mark I.

    2003-01-01

    Candida tropicalis ATCC 20336 can grow on fatty acids or alkanes as its sole source of carbon and energy, but strains blocked in β-oxidation convert these substrates to long-chain α,ω-dicarboxylic acids (diacids), compounds of potential commercial value (Picataggio et al., Biotechnology 10:894-898, 1992). The initial step in the formation of these diacids, which is thought to be rate limiting, is ω-hydroxylation by a cytochrome P450 (CYP) monooxygenase. C. tropicalis ATCC 20336 contains a family of CYP genes, and when ATCC 20336 or its derivatives are exposed to oleic acid (C18:1), two cytochrome P450s, CYP52A13 and CYP52A17, are consistently strongly induced (Craft et al., this issue). To determine the relative activity of each of these enzymes and their contribution to diacid formation, both cytochrome P450s were expressed separately in insect cells in conjunction with the C. tropicalis cytochrome P450 reductase (NCP). Microsomes prepared from these cells were analyzed for their ability to oxidize fatty acids. CYP52A13 preferentially oxidized oleic acid and other unsaturated acids to ω-hydroxy acids. CYP52A17 also oxidized oleic acid efficiently but converted shorter, saturated fatty acids such as myristic acid (C14:0) much more effectively. Both enzymes, in particular CYP52A17, also oxidized ω-hydroxy fatty acids, ultimately generating the α,ω-diacid. Consideration of these different specificities and selectivities will help determine which enzymes to amplify in strains blocked for β-oxidation to enhance the production of dicarboxylic acids. The activity spectrum also identified other potential oxidation targets for commercial development. PMID:14532054

  20. Effect of Humic Acid on As Redox Transformation and Kinetic Adsorption onto Iron Oxide Based Adsorbent (IBA)

    PubMed Central

    Fakour, Hoda; Lin, Tsair-Fuh

    2014-01-01

    Due to the importance of adsorption kinetics and redox transformation of arsenic (As) during the adsorption process, the present study elucidated natural organic matter (NOM) effects on As adsorption-desorption kinetics and speciation transformation. The experimental procedures were conducted by examining interactions of arsenate and arsenite with different concentrations of humic acid (HA) as a model representative of NOM, in the presence of iron oxide based adsorbent (IBA), as a model solid surface in three environmentally relevant conditions, including the simultaneous adsorption of both As and HA onto IBA, HA adsorption onto As-presorbed IBA, and As adsorption onto HA-presorbed IBA. Experimental adsorption-desorption data were all fitted by original and modified Lagergren pseudo-first and -second order adsorption kinetic models, respectively. Weber’s intraparticle diffusion was also used to gain insight into the mechanisms and rate controlling steps, which the results suggested that intraparticle diffusion of As species onto IBA is the main rate-controlling step. Different concentrations of HA mediated the redox transformation of As species, with a higher oxidation ability than reduction. The overall results indicated the significant effect of organic matter on the adsorption kinetics and redox transformation of As species, and consequently, the fate, transport and mobility of As in different environmentally relevant conditions. PMID:25325357

  1. Metabolic Transformation of Mevalonic Acid by an Enzyme System from Peas 1

    PubMed Central

    Pollard, C. J.; Bonner, J.; Haagen-Smit, A. J.; Nimmo, C. C.

    1966-01-01

    En enzyme system has been found in peas which converts mevalonic acid to isoprenoid compounds. Among the intermediates in such conversion are mevalonic acid-5-phosphate and pyrophosphate, isopentenyl pyrophosphate and dimethylallylpyrophosphate. Among the products formed by the system are the pyrophosphates of geraniol, farnesol, nerolidol and higher isoprenoid alcohols. PMID:16656233

  2. Acid-Base-Triggered Structural Transformation of a Polyoxometalate Core Inside a Dodecahedrane-like Silver Thiolate Shell.

    PubMed

    Liu, Hong; Song, Chao-Yu; Huang, Ren-Wu; Zhang, Yu; Xu, Hong; Li, Mei-Jia; Zang, Shuang-Quan; Gao, Guang-Gang

    2016-03-01

    Self-assembly of metavanadate and organosilver(I) salts leads to a novel dodecahedrane-like [Ag30 ((t) BuS)20 ](10+) silver(I) thiolate nanocage that tightly wraps an unusual C2h polyoxovanadate anion. The polyoxovanadate core undergoes transformation to a D3d configuration upon acidification, and reverts back to its original C2h structure upon addition of base. Chromism was observed for the silver(I) thiolate cluster during the configurational change of the central polyoxovanadate core; the color of the solution changes reversibly from green to dark yellow. This work represents the first reported example of chromic polyoxometalate-templated silver(I) thiolate shells that respond to external acid-base stimuli. It also represents an important advance in providing crystallographic proof that structural transformations occur in a nanoscale core-shell cluster. PMID:26879840

  3. Complementary cavity-enhanced spectrometers to investigate the OH + CH combination band in trans-formic acid

    NASA Astrophysics Data System (ADS)

    Golebiowski, D.; Fldes, T.; Vanfleteren, T.; Herman, M.; Perrin, A.

    2015-07-01

    We have used continuous-wave cavity ring-down and femto-Fourier transform-cavity-enhanced absorption spectrometers to record the spectrum of the OH-stretching + CH-stretching (?1 + ?2) combination band in trans-formic acid, with origin close to 6507 cm-1. They, respectively, allowed resolving and simplifying the rotational structure of the band near its origin under jet-cooled conditions (Trot = 10 K) and highlighting the overview of the band under room temperature conditions. The stronger B-type and weaker A-type subbands close to the band origin could be assigned, as well as the main B-type Q branches. The high-resolution analysis was hindered by numerous, severe perturbations. Rotational constants are reported with, however, limited physical meaning. The ?1 + ?2 transition moment is estimated from relative intensities to be 24 away from the principal b-axis of inertia.

  4. Complementary cavity-enhanced spectrometers to investigate the OH + CH combination band in trans-formic acid.

    PubMed

    Golebiowski, D; Fldes, T; Vanfleteren, T; Herman, M; Perrin, A

    2015-07-01

    We have used continuous-wave cavity ring-down and femto-Fourier transform-cavity-enhanced absorption spectrometers to record the spectrum of the OH-stretching + CH-stretching (?1 + ?2) combination band in trans-formic acid, with origin close to 6507 cm(-1). They, respectively, allowed resolving and simplifying the rotational structure of the band near its origin under jet-cooled conditions (Trot = 10 K) and highlighting the overview of the band under room temperature conditions. The stronger B-type and weaker A-type subbands close to the band origin could be assigned, as well as the main B-type Q branches. The high-resolution analysis was hindered by numerous, severe perturbations. Rotational constants are reported with, however, limited physical meaning. The ?1 + ?2 transition moment is estimated from relative intensities to be 24 away from the principal b-axis of inertia. PMID:26156476

  5. "In vivo" effects of acetylsalicylic acid and two ether derived compounds on primary immune response and lymphoblastic transformation.

    PubMed

    Barasoain, I; Rojo, J M; Portols, A

    1980-12-01

    A comparison was performed of acetylsalicylic acid and two ether derivatives (Benorilate and Eterilate) and indomethacin in order to ascertain the in vivo effects on the lymphoblastic transformation and the primary immune response in mice. The humoral response in Benorilate-and Eterilate-treated mice was 40-50% lower than that of the controls, whereas in acetylsalicylic acid-treated mice the response was only 25% inhibited. The number of immunoglobulin synthesizing cells was neither reduced by acetylsalicylic acid nor by its derivatives, although indomethacin treatments (used for comparative purposes) inhibited by 40% the number of direct plaque-forming cells on the days tested. Mitogen-induced proliferation of spleen lymphocytes was also inhibited in the treated mice; these inhibitions were negligible in the case of cells from acetylsalicylic acid-treated mice activated by concanavalin A and slight in cells from Benorilate-treated mice activated by bacterial lipopolysaccharide. When lymphocytes from drug-treated animals were further cultured in the presence of the same drug, a variable inhibition of mitogen-induced proliferation was observed. These different in vivo effects of acetylsalicylic acid and the two ether derivatives and indomethacin may be due to a distinct action on diverse lymphocyte subpopulations altering their cellular collaborative interactions or modifying the prostaglandin availability. PMID:6109698

  6. Final Report: Theoretical Studies on Radiation-Induced Transformations in Nucleic Acid Bases, May 1, 1993 - April 30, 1996

    SciTech Connect

    Adamowicz, Ludwik

    1996-04-30

    In the proposal we identified several elemental molecular properties related to the effects observed in genetic material exposed to ionizing irradiation, and we studied them by means of the ab-initio quantum chemistry. The chemistry of irradiation is complex and biological consequences are significant. This includes cell death, mutations, carcinogenic transformations, etc. In the proposal we theoretically modeled several elemental processes related to the radiolysis of components of the nucleic acids, i.e., the pyrimidine nucleobases cytosine, uracine and thymine. Based on the state-of-the-art ab-initio calculations, we obtained information on the structural and spectroscopic properties of transition intermediate reactants.

  7. Transformation with Oncogenic Ras and the Simian Virus 40 T Antigens Induces Caspase-Dependent Sensitivity to Fatty Acid Biosynthetic Inhibition

    PubMed Central

    Xu, Shihao; Spencer, Cody M.

    2015-01-01

    ABSTRACT Oncogenesis is frequently accompanied by the activation of specific metabolic pathways. One such pathway is fatty acid biosynthesis, whose induction is observed upon transformation of a wide variety of cell types. Here, we explored how defined oncogenic alleles, specifically the simian virus 40 (SV40) T antigens and oncogenic Ras12V, affect fatty acid metabolism. Our results indicate that SV40/Ras12V-mediated transformation of fibroblasts induces fatty acid biosynthesis in the absence of significant changes in the concentration of fatty acid biosynthetic enzymes. This oncogene-induced activation of fatty acid biosynthesis was found to be mammalian target of rapamycin (mTOR) dependent, as it was attenuated by rapamycin treatment. Furthermore, SV40/Ras12V-mediated transformation induced sensitivity to treatment with fatty acid biosynthetic inhibitors. Pharmaceutical inhibition of acetyl-coenzyme A (CoA) carboxylase (ACC), a key fatty acid biosynthetic enzyme, induced caspase-dependent cell death in oncogene-transduced cells. In contrast, isogenic nontransformed cells were resistant to fatty acid biosynthetic inhibition. This oncogene-induced sensitivity to fatty acid biosynthetic inhibition was independent of the cells' growth rates and could be attenuated by supplementing the medium with unsaturated fatty acids. Both the activation of fatty acid biosynthesis and the sensitivity to fatty acid biosynthetic inhibition could be conveyed to nontransformed breast epithelial cells through transduction with oncogenic Ras12V. Similar to what was observed in the transformed fibroblasts, the Ras12V-induced sensitivity to fatty acid biosynthetic inhibition was independent of the proliferative status and could be attenuated by supplementing the medium with unsaturated fatty acids. Combined, our results indicate that specific oncogenic alleles can directly confer sensitivity to inhibitors of fatty acid biosynthesis. IMPORTANCE Viral oncoproteins and cellular mutations drive the transformation of normal cells to the cancerous state. These oncogenic alterations induce metabolic changes and dependencies that can be targeted to kill cancerous cells. Here, we find that the cellular transformation resulting from combined expression of the SV40 early region with an oncogenic Ras allele is sufficient to induce cellular susceptibility to fatty acid biosynthetic inhibition. Inhibition of fatty acid biosynthesis in these cells resulted in programmed cell death, which could be rescued by supplementing the medium with nonsaturated fatty acids. Similar results were observed with the expression of oncogenic Ras in nontransformed breast epithelial cells. Combined, our results suggest that specific oncogenic alleles induce metabolic dependencies that can be exploited to selectively kill cancerous cells. PMID:25855740

  8. Uric acid and transforming growth factor in fructose-induced production of reactive oxygen species in skeletal muscle.

    PubMed

    Madlala, Hlengiwe P; Maarman, Gerald J; Ojuka, Edward

    2016-04-01

    The consumption of fructose, a major constituent of the modern diet, has raised increasing concern about the effects of fructose on health. Research suggests that excessive intake of fructose (>50 g/d) causes hyperuricemia, insulin resistance, mitochondrial dysfunction, de novo lipogenesis by the liver, and increased production of reactive oxygen species (ROS) in muscle. In a number of tissues, uric acid has been shown to stimulate the production of ROS via activation of transforming growth factor β1 and NADPH (nicotinamide adenine dinucleotide phosphate) oxidase 4. The role of uric acid in fructose-induced production of ROS in skeletal muscle, however, has not been investigated. This review examines the evidence for fructose-induced production of ROS in skeletal muscle, highlights proposed mechanisms, and identifies gaps in current knowledge. PMID:26946251

  9. Fourier transform infrared studies of model polar stratospheric cloud surfaces - Growth and evaporation of ice and nitric acid/ice

    NASA Technical Reports Server (NTRS)

    Tolbert, Margaret A.; Middlebrook, Ann M.

    1990-01-01

    Fourier-transform infrared surface studies are used to probe the microphysical properties of nitric acid trihydrate (NAT) and ice films representative of type I and II polar stratospheric clouds (PSC). Experiments indicate that, on initial exposure to 1.8 microtorr of HNO3, a layer of ice is quantitatively converted to NAT. However, conversion of ice to NAT does not proceed indefinitely, but rather the system reaches saturation. For longer exposures or higher HNO3 pressures, NAM becomes the dominant nitric acid containing species on the surface. Evaporation studies were performed to test the feasibility of a recent denitrification mechanism. The results indicate that ice coated with 0.20 micron of NAT evaporates at a temperature of about 4 C higher than uncoated ice.

  10. Microbial transformations of ferulic acid by Saccharomyces cerevisiae and Pseudomonas fluorescens.

    PubMed Central

    Huang, Z; Dostal, L; Rosazza, J P

    1993-01-01

    Saccharomyces cerevisiae (dry baker's yeast) and Pseudomonas fluorescens were used to convert trans-ferulic acid into 4-hydroxy-3-methoxystyrene in 96 and 89% yields, respectively. The metabolites were isolated by solid-phase extraction and analyzed by thin-layer chromatography and high-performance liquid chromatography. The identities of the metabolites were determined by 1H- and 13C-nuclear magnetic resonance spectroscopy and by mass spectrometry. The mechanism of the decarboxylation of ferulic acid was investigated by measuring the degree and position of deuterium incorporated into the styrene derivative from D2O by mass spectrometry and by both proton and deuterium nuclear magnetic resonance spectroscopies. Resting cells of baker's yeast reduced ferulic acid to 4-hydroxy-3-methoxyphenylpropionic acid in 54% yield when incubations were under an argon atmosphere. PMID:8395165

  11. Bacterial production and transformation of dissolved neutral sugars and amino acids in seawater

    NASA Astrophysics Data System (ADS)

    Jrgensen, L.; Lechtenfeld, O.; Benner, R.; Middelboe, M.; Stedmon, C. A.

    2014-04-01

    Dissolved organic matter (DOM) in the ocean consists of a heterogeneous mixture of molecules, most of which are of unknown origin. Neutral sugars and amino acids are among the few recognizable biomolecules in DOM, and the molecular composition of these biomolecules is shaped primarily by biological production and degradation processes. This study provides insight into the bioavailability of biomolecules as well as the chemical composition of DOM produced by bacteria. The molecular compositions of neutral sugars and amino acids were investigated in DOM produced by bacteria and in DOM remaining after long-term bacterial degradation. Results from bioassay incubations (32 days) with natural and artificial seawater, indicate that the molecular compositions following bacterial degradation are not strongly influenced by the initial substrate or bacterial community. The molecular composition of neutral sugars released by bacteria was characterized by a high glucose content (47 mol%) and heterogeneous contributions from other neutral sugars (3-14 mol%). DOM remaining after bacterial degradation was characterized by a high galactose content (33 mol%), followed by glucose (22 mol%) and the remaining neutral sugars (7-11 mol%). The ratio of D-amino acids to L-amino acids increased during the experiments as a response to bacterial degradation, and after 32 days the D/L ratios of aspartic acid, glutamic acid, serine and alanine reached around 0.79, 0.32, 0.30 and 0.51 in all treatments, respectively. The striking similarity in neutral sugar and amino acid compositions between natural and artificial seawater samples, suggests that the microbial carbon pump also applies for neutral sugars and amino acids and that bacterially-produced biomolecules persist for long periods in the ocean.

  12. Hypoxic and Ras-transformed cells support growth by scavenging unsaturated fatty acids from lysophospholipids

    PubMed Central

    Kamphorst, Jurre J.; Cross, Justin R.; Fan, Jing; de Stanchina, Elisa; Mathew, Robin; White, Eileen P.; Thompson, Craig B.; Rabinowitz, Joshua D.

    2013-01-01

    Cancer cell growth requires fatty acids to replicate cellular membranes. The kinase Akt is known to up-regulate fatty acid synthesis and desaturation, which is carried out by the oxygen-consuming enzyme stearoyl-CoA desaturase (SCD)1. We used 13C tracers and lipidomics to probe fatty acid metabolism, including desaturation, as a function of oncogene expression and oxygen availability. During hypoxia, flux from glucose to acetyl-CoA decreases, and the fractional contribution of glutamine to fatty acid synthesis increases. In addition, we find that hypoxic cells bypass de novo lipogenesis, and thus, both the need for acetyl-CoA and the oxygen-dependent SCD1-reaction, by scavenging serum fatty acids. The preferred substrates for scavenging are phospholipids with one fatty acid tail (lysophospholipids). Hypoxic reprogramming of de novo lipogenesis can be reproduced in normoxic cells by Ras activation. This renders Ras-driven cells, both in culture and in allografts, resistant to SCD1 inhibition. Thus, a mechanism by which oncogenic Ras confers metabolic robustness is through lipid scavenging. PMID:23671091

  13. [Responses of rhizosphere nitrogen and phosphorus transformations to different acid rain intensities in a hilly red soil tea plantation].

    PubMed

    Chen, Xi; Chen, Fu-sheng; Ye, Su-qiong; Yu, Su-qin; Fang, Xiang-min; Hu, Xiao-fei

    2015-01-01

    Tea (Camellia sinensis) plantation in hilly red soil region has been long impacted by acid deposition, however its effects on nitrogen (N) and phosphorus (P) transformations in rhizosphere soils remain unclear. A 25-year old tea plantation in a typical hilly red soil region was selected for an in situ simulation experiment treated by pH 4.5, pH 3.5, pH 2.5 and control. Rhizosihere and bulk soils were collected in the third year from the simulated acid deposition experiment. Soil mineral N, available P contents and major enzyme activities were analyzed using the chemical extraction and biochemical methods, and N and P mineralization rates were estimated using the indoor aerobic incubation methods. Our results showed that compared to the control, the treatments of pH 4.5, pH 3.5 and pH 2.5, respectively decreased 7.1%, 42.1% and 49.9% NO3(-)-N, 6.4%, 35.9% and 40.3% mineral N, 10.5%, 41.1% and 46.9% available P, 18.7%, 30.1% and 44.7% ammonification rate, 3.6%, 12.7% and 38.8% net N-mineralization rate, and 31.5%, 41.8% and 63.0% P mineralization rate in rhizosphere soils; however, among the 4 treatments, rhizosphere soil nitrification rate was not significantly different, the rhizosphere soil urease and acid phosphatase activities generally increased with the increasing intensity of acid rain (P<0.05). In bulk soil, compared with the control, the treatments of pH 4.5, pH 3.5 and pH 2.5 did not cause significant changes in NO3(-)-N, mineral N, available P as well as in the rates of nitrification, ammonification, net N-mineralization and P mineralization. With increasing the acid intensity, the rhizosphere effects of NH4+-N, NO3(-)-N, mineral N, ammonification and net N-mineralization rates were altered from positive to negative effects, those of urease and acid phosphatease showed the opposite trends, those of available P and P mineralization were negative and that of nitrification was positive. In sum, prolonged elevated acid rain could reduce N and P transformation rates, decrease their availability, alter their rhizosphere effects, and have impact on nutrient cycling in tea plantation. PMID:25985647

  14. Adsorption of Amino Acids (Ala, Cys, His, Met) on Zeolites: Fourier Transform Infrared and Raman Spectroscopy Investigations

    NASA Astrophysics Data System (ADS)

    Carneiro, Cristine E. A.; de Santana, Henrique; Casado, Clara; Coronas, Joaquin; Zaia, Dimas A. M.

    2011-06-01

    Minerals adsorb more amino acids with charged R-groups than amino acids with uncharged R-groups. Thus, the peptides that form from the condensation of amino acids on the surface of minerals should be composed of amino acid residues that are more charged than uncharged. However, most of the amino acids (74%) in today's proteins have an uncharged R-group. One mechanism with which to solve this paradox is the use of organophilic minerals such as zeolites. Over the range of pH (pH 2.66-4.50) used in these experiments, the R-group of histidine (His) is positively charged and neutral for alanine (Ala), cysteine (Cys), and methionine (Met). In acidic hydrothermal environments, the pH could be even lower than those used in this study. For the pH range studied, the zeolites were negatively charged, and the overall charge of all amino acids was positive. The conditions used here approximate those of prebiotic Earth. The most important finding of this work is that the relative concentrations of each amino acid (X=His, Met, Cys) to alanine (X/Ala) are close to 1.00. This is an important result with regard to prebiotic chemistry because it could be a solution for the paradox stated above. Pore size did not affect the adsorption of Cys and Met on zeolites, and the Si/Al ratio did not affect the adsorption of Cys, His, and Met. ZSM-5 could be used for the purification of Cys from other amino acids (Student-Newman-Keuls test, p<0.05), and mordenite could be used for separation of amino acids from each other (Student-Newman-Keuls test, p<0.05). As shown by Fourier transform infrared (FT-IR) spectra, Ala interacts with zeolites through the group, and methionine-zeolite interactions involve the COO, , and CH3 groups. FT-IR spectra show that the interaction between the zeolites and His is weak. Cys showed higher adsorption on all zeolites; however, the hydrophobic Van der Waals interaction between zeolites and Cys is too weak to produce any structural changes in the Cys groups (amine, carboxylic, sulfhydryl, etc.); thus, the FT-IR and Raman spectra are the same as those of solid Cys.

  15. Plant Lectin Can Target Receptors Containing Sialic Acid, Exemplified by Podoplanin, to Inhibit Transformed Cell Growth and Migration

    PubMed Central

    Shen, Yongquan; Acharya, Nimish K.; Han, Min; McNulty, Dean E.; Hasegawa, Hitoki; Hyodo, Toshinori; Senga, Takeshi; Geng, Jian-Guo; Kosciuk, Mary; Shin, Seung S.; Goydos, James S.; Temiakov, Dmitry; Nagele, Robert G.; Goldberg, Gary S.

    2012-01-01

    Cancer is a leading cause of death of men and women worldwide. Tumor cell motility contributes to metastatic invasion that causes the vast majority of cancer deaths. Extracellular receptors modified by ?2,3-sialic acids that promote this motility can serve as ideal chemotherapeutic targets. For example, the extracellular domain of the mucin receptor podoplanin (PDPN) is highly O-glycosylated with ?2,3-sialic acid linked to galactose. PDPN is activated by endogenous ligands to induce tumor cell motility and metastasis. Dietary lectins that target proteins containing ?2,3-sialic acid inhibit tumor cell growth. However, anti-cancer lectins that have been examined thus far target receptors that have not been identified. We report here that a lectin from the seeds of Maackia amurensis (MASL) with affinity for O-linked carbohydrate chains containing sialic acid targets PDPN to inhibit transformed cell growth and motility at nanomolar concentrations. Interestingly, the biological activity of this lectin survives gastrointestinal proteolysis and enters the cardiovascular system to inhibit melanoma cell growth, migration, and tumorigenesis. These studies demonstrate how lectins may be used to help develop dietary agents that target specific receptors to combat malignant cell growth. PMID:22844530

  16. Structures of aspartic acid-96 in the L and N intermediates of bacteriorhodopsin: analysis by Fourier transform infrared spectroscopy

    NASA Technical Reports Server (NTRS)

    Maeda, A.; Sasaki, J.; Shichida, Y.; Yoshizawa, T.; Chang, M.; Ni, B.; Needleman, R.; Lanyi, J. K.

    1992-01-01

    The light-induced difference Fourier transform infrared spectrum between the L or N intermediate minus light-adapted bacteriorhodopsin (BR) was measured in order to examine the protonated states and the changes in the interactions of carboxylic acids of Asp-96 and Asp-115 in these intermediates. Vibrational bands due to the protonated and unprotonated carboxylic acid were identified by isotope shift and band depletion upon substitution of Asp-96 or -115 by asparagine. While the signal due to the deprotonation of Asp-96 was clearly observed in the N intermediate, this residue remained protonated in L. Asp-115 was partially deprotonated in L. The C = O stretching vibration of protonated Asp-96 of L showed almost no shift upon 2H2O substitution, in contrast to the corresponding band of Asp-96 or Asp-115 of BR, which shifted by 9-12 cm-1 under the same conditions. In the model system of acetic acid in organic solvents, such an absence of the shift of the C = O stretching vibration of the protonated carboxylic acid upon 2H2O substitution was seen only when the O-H of acetic acid is hydrogen-bonded. The non-hydrogen-bonded monomer showed the 2H2O-dependent shift. Thus, the O-H bond of Asp-96 enters into hydrogen bonding upon conversion of BR to L. Its increased hydrogen bonding in L is consistent with the observed downshift of the O-H stretching vibration of the carboxylic acid of Asp-96.

  17. Characterization of naphthenic acids by gas chromatography-Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Ortiz, Xavier; Jobst, Karl J; Reiner, Eric J; Backus, Sean M; Peru, Kerry M; McMartin, Dena W; O'Sullivan, Gwen; Taguchi, Vince Y; Headley, John V

    2014-08-01

    During the bitumen extraction from the oil sands of Alberta, large volumes of process water containing naphthenic acids are stored in tailing ponds. The naphthenic acids along with other components in the processed waters are known to be toxic in aquatic environments. In view of the complex matrix and the toxicity of the processed waters, there is a need for complementary analytical techniques for comprehensive characterization of the naphthenic acid mixtures. This study reports the online gas chromatographic separation of naphthenic acid mixtures prior to ultrahigh resolution mass spectrometry detection, using electron and chemical ionization. Two oil sands processed water samples and two groundwater samples were characterized to evaluate the performance of the instrumental technique. The high mass resolution of the system enabled visualization of the data using Kendrick mass defect plots. The addition of gas chromatographic separations enabled visualization of the data as unique compound class elution fingerprints. The technique is demonstrated to be a valuable tool for chemical fingerprinting of naphthenic acids. PMID:25001115

  18. A study of the autoxidation of some unsaturated fatty acid methyl esters using Fourier transform Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Agbenyega, J. K.; Claybourn, M.; Ellis, G.

    Near-infrared Fourier transform Raman and Fourier transform infrared spectroscopy have been used to investigate the chemical changes taking place during the curing reaction of several fatty acid methyl esters, which are used for modelling processes in the autoxidation of alkyd resin coatings. We have studied methyl oleate, methyl linoleate, and methyl linolenate in an attempt to monitor the degree of unsaturation within the fatty acid methyl esters (FAMES) during the complex autoxidation/polymerisation reaction that takes place once the paint system is coated onto a substrate and exposed to the atmosphere. The peaks around 1655 cm -1 have been assigned as follows: to the trans isomer at 1670 cm -1, the cis isomer at 1655 cm -1 and the conjugated structure at 1640 cm -1 [B. Schrader, Raman/Infrared Atlas of Organic Compounds (2nd Edn), VCH, Weinheim (1989); J. K. Abenyega, M. Claybourn and G. Ellis, in preparations]. Raman spectra for the cure of methyl linoleate after 24 h show several interesting features, suggesting the formation of a highly conjugated cyclic structure. Current theories about the mechanism for the autoxidation of methyl linoleate make no mention of this aromatic product.

  19. Transformation of 5-O-caffeoylquinic acid in blueberries during high-temperature processing.

    PubMed

    Dawidowicz, Andrzej L; Typek, Rafal

    2014-11-12

    Chlorogenic acid (CQA), an ester of caffeic with quinic acid, is a natural compound found in a wide array of plants. Although coffee beans are most frequently mentioned as plant products remarkably rich in CQAs, their significant amounts can also be found in many berries, for example, blueberries. This paper shows and discusses the thermal stability of the main CQA representative, that is, 5-O-caffeoylquinic acid (5-CQA), during high-temperature processing of blueberries (as in the production of blueberry foods) in systems containing sucrose in low and high concentration. It has been found that up to 11 components (5-CQA derivatives and its reaction product with water) can be formed from 5-CQA during the processing of blueberries. Their formation speed depends on the sucrose concentration in the processed system, which has been confirmed in the artificial system composed of 5-CQA water solution containing different amounts of the sugar. PMID:25336323

  20. Thermal transformation of bioactive caffeic acid on fumed silica seen by UV-Vis spectroscopy, thermogravimetric analysis, temperature programmed desorption mass spectrometry and quantum chemical methods.

    PubMed

    Kulik, Tetiana V; Lipkovska, Natalia O; Barvinchenko, Valentyna M; Palyanytsya, Borys B; Kazakova, Olga A; Dudik, Olesia O; Menyhárd, Alfréd; László, Krisztina

    2016-05-15

    Thermochemical studies of hydroxycinnamic acid derivatives and their surface complexes are important for the pharmaceutical industry, medicine and for the development of technologies of heterogeneous biomass pyrolysis. In this study, structural and thermal transformations of caffeic acid complexes on silica surfaces were studied by UV-Vis spectroscopy, thermogravimetric analysis, temperature programmed desorption mass spectrometry (TPD MS) and quantum chemical methods. Two types of caffeic acid surface complexes are found to form through phenolic or carboxyl groups. The kinetic parameters of the chemical reactions of caffeic acid on silica surface are calculated. The mechanisms of thermal transformations of the caffeic chemisorbed surface complexes are proposed. Thermal decomposition of caffeic acid complex chemisorbed through grafted ester group proceeds via three parallel reactions, producing ketene, vinyl and acetylene derivatives of 1,2-dihydroxybenzene. Immobilization of phenolic acids on the silica surface improves greatly their thermal stability. PMID:26939077

  1. Morphological transformation of Helicobacter pylori during prolonged incubation: association with decreased acid resistance.

    PubMed Central

    Moshkowitz, M; Gorea, A; Arber, N; Konikoff, F; Berger, S; Gilat, T

    1994-01-01

    The survival of clinical isolates of H pylori at two cultural ages (two and four days) at pH 2, in the presence of different buffers, with and without urea, was investigated. It was found that the morphological changes which occur with longer incubation of H pylori have an inverse correlation with its resistance to an acidic environment. The finding that the addition of urea almost reversed this phenomenon and prolonged survival of the cultures emphasises the role of urea in the survival of H pylori in acidic environments. Images PMID:8132834

  2. Suberoylanilide hydroxamic acid (SAHA) inhibits EGF-induced cell transformation via reduction of cyclin D1 mRNA stability

    SciTech Connect

    Zhang, Jingjie; Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 ; Ouyang, Weiming; Li, Jingxia; Zhang, Dongyun; Yu, Yonghui; Wang, York; Li, Xuejun; Huang, Chuanshu

    2012-09-01

    Suberoylanilide hydroxamic acid (SAHA) inhibiting cancer cell growth has been associated with its downregulation of cyclin D1 protein expression at transcription level or translation level. Here, we have demonstrated that SAHA inhibited EGF-induced Cl41 cell transformation via the decrease of cyclin D1 mRNA stability and induction of G0/G1 growth arrest. We found that SAHA treatment resulted in the dramatic inhibition of EGF-induced cell transformation, cyclin D1 protein expression and induction of G0/G1 growth arrest. Further studies showed that SAHA downregulation of cyclin D1 was only observed with endogenous cyclin D1, but not with reconstitutionally expressed cyclin D1 in the same cells, excluding the possibility of SAHA regulating cyclin D1 at level of protein degradation. Moreover, SAHA inhibited EGF-induced cyclin d1 mRNA level, whereas it did not show any inhibitory effect on cyclin D1 promoter-driven luciferase reporter activity under the same experimental conditions, suggesting that SAHA may decrease cyclin D1 mRNA stability. This notion was supported by the results that treatment of cells with SAHA decreased the half-life of cyclin D1 mRNA from 6.95 h to 2.57 h. Consistent with downregulation of cyclin D1 mRNA stability, SAHA treatment also attenuated HuR expression, which has been well-characterized as a positive regulator of cyclin D1 mRNA stability. Thus, our study identifies a novel mechanism responsible for SAHA inhibiting cell transformation via decreasing cyclin D1 mRNA stability and induction of G0/G1 growth arrest in Cl41 cells. -- Highlights: ? SAHA inhibits cell transformation in Cl41 cells. ? SAHA suppresses Cyclin D1 protein expression. ? SAHA decreases cyclin D1 mRNA stability.

  3. CHEMICAL TRANSFORMATION MODULES FOR EULERIAN ACID DEPOSITION MODELS. VOLUME 1. THE GAS-PHASE CHEMISTRY

    EPA Science Inventory

    This study focuses on the review and evaluation of mechanistic and kinetic data for the gas-phase reactions that lead to the production of acidic substances in the environment. A master mechanism is designed that treats oxides, sulfur dioxide, ozone, hydrogen peroxide, ammonia, t...

  4. CHEMICAL TRANSFORMATION MODULES FOR EULERIAN ACID DEPOSITION MODELS. VOLUME 2. THE AQUEOUS-PHASE CHEMISTRY

    EPA Science Inventory

    This study focuses on the review and evaluation of mechanistic and kinetic data for aqueous-phase reactions that lead to the production of acidic substances in the environment. The intent of this research is to provide a framework that can be used to develop a state-of-the-art aq...

  5. Rapid preparation of rare ginsenosides by acid transformation and their structure-activity relationships against cancer cells

    PubMed Central

    Quan, Kai; Liu, Qun; Wan, Jin-Yi; Zhao, Yi-Jing; Guo, Ru-Zhou; Alolga, Raphael N.; Li, Ping; Qi, Lian-Wen

    2015-01-01

    The anticancer activities of ginsenosides are widely reported. The structure-activity relationship of ginsenosides against cancer is not well elucidated because of the unavailability of these compounds. In this work, we developed a transformation method to rapidly produce rare dehydroxylated ginsenosides by acid treatment. The optimized temperature, time course, and concentration of formic acid were 120°C, 4 h and 0.01%, respectively. From 100 mg of Rh1, 8.3 mg of Rk3 and 18.7 mg of Rh4 can be produced by acid transformation. Similarly, from 100 mg of Rg3, 7.4 mg of Rk1 and 15.1 mg of Rg5 can be produced. From 100 mg of Rh2, 8.3 mg of Rk2 and 12.7 mg of Rh3 can be generated. Next, the structure-activity relationships of 23 ginsenosides were investigated by comparing their cytotoxic effects on six human cancer cells, including HCT-116, HepG2, MCF-7, Hela, PANC-1, and A549. The results showed that: (1) the cytotoxic effect of ginsenosides is inversely related to the sugar numbers; (2) sugar linkages rank as C-3 > C-6 > C-20; (3) the protopanaxadiol-type has higher activities; (4) having the double bond at the terminal C20-21 exhibits stronger activity than that at C20-22; and (5) 20(S)-ginsenosides show stronger effects than their 20(R)-stereoisomers. PMID:25716943

  6. Glucose transformation to 5-hydroxymethylfurfural in acidic ionic liquid: A quantum mechanical study.

    PubMed

    Arifin; Puripat, Maneeporn; Yokogawa, Daisuke; Parasuk, Vudhichai; Irle, Stephan

    2016-01-30

    Isomerization and transformation of glucose and fructose to 5-hydroxymethylfurfural (HMF) in both ionic liquids (ILs) and water has been studied by the reference interaction site model self-consistent field spatial electron density distribution (RISM-SCF-SEDD) method coupled with ab initio electronic structure theory, namely coupled cluster single, double, and perturbative triple excitation (CCSD(T)). Glucose isomerization to fructose has been investigated via cyclic and open chain mechanisms. In water, the calculations support the cyclic mechanism of glucose isomerization; with the predicted activation free energy is 23.8 kcal mol(-1) at experimental condition. Conversely, open ring mechanism is more favorable in ILs with the energy barrier is 32.4 kcal mol(-1) . Moreover, the transformation of fructose into HMF via cyclic mechanism is reasonable; the calculated activation barriers are 16.0 and 21.5 kcal mol(-1) in aqueous and ILs solutions, respectively. The solvent effects of ILs could be explained by the decomposition of free energies and radial distribution functions of solute-solvent that are produced by RISM-SCF-SEDD. © 2015 Wiley Periodicals, Inc. PMID:26453901

  7. [Fourier transform infrared spectra analysis of nucleic acid in human breast tissue].

    PubMed

    Fan, Xiao-yan; Huo, Hong; Huang, Wei-dong; Che, Xun; Wang, Xing-fu

    2004-01-01

    DNA molecular constitution is damaged to result in the inductive variation of base structure in female breast tissue under the influence of physical factors and chemical factors. The present research indicated that the FTIR spectra can reflect sensitively the change in the constitution. Our findings indicated that normal, benign and cancerous breast tissues are different in constitution and content of protein, nucleic acid and sugar, comparing the FTIR spectra, deconvolution spectra and date analysis. The result indicated that the content of collagen protein and nucleic acid increased obviously in cancerous tissue, while the content of glycoprotein increased gradually except mucinous carcinoma. After extracting nucleic acid of breast tissue, we further investigated the difference of constitution and content of base and phosphate by comparing normal, benign and cancerous breast tissues. The spectra and spectral data showed that the degree of hydrogen-bonding of base ring guanine (Gue) increased in cancerous tissue, base ring adenine (Ade) presented mostly in oxydic 8-OH-Ade via the attack of the *OH in cancerous breast, the peak position shifted to higher wave number with enhancing of C=N vibration, and the content of phosphate increased. After deconvolution, the ratio A1080/A1050 showed that the amount of PO2- relative to C-O increased from normal to cancerous breast tissues. It provided a important basis to study the mechanism of cancerization from molecular biology and molecular medicine. PMID:15768975

  8. Lipoxygenase-catalyzed transformation of epoxy fatty acids to hydroxy-endoperoxides: a potential P450 and lipoxygenase interaction[S

    PubMed Central

    Teder, Tarvi; Boeglin, William E.; Brash, Alan R.

    2014-01-01

    Herein, we characterize a generally applicable transformation of fatty acid epoxides by lipoxygenase (LOX) enzymes that results in the formation of a five-membered endoperoxide ring in the end product. We demonstrated this transformation using soybean LOX-1 in the metabolism of 15,16-epoxy-α-linolenic acid, and murine platelet-type 12-LOX and human 15-LOX-1 in the metabolism of 14,15-epoxyeicosatrienoic acid (14,15-EET). A detailed examination of the transformation of the two enantiomers of 15,16-epoxy-α-linolenic acid by soybean LOX-1 revealed that the expected primary product, a 13S-hydroperoxy-15,16-epoxide, underwent a nonenzymatic transformation in buffer into a new derivative that was purified by HPLC and identified by UV, LC-MS, and 1H-NMR as a 13,15-endoperoxy-16-hydroxy-octadeca-9,11-dienoic acid. The configuration of the endoperoxide (cis or trans side chains) depended on the steric relationship of the new hydroperoxy moiety to the enantiomeric configuration of the fatty acid epoxide. The reaction mechanism involves intramolecular nucleophilic substitution (SNi) between the hydroperoxy (nucleophile) and epoxy group (electrophile). Equivalent transformations were documented in metabolism of the enantiomers of 14,15-EET by the two mammalian LOX enzymes, 15-LOX-1 and platelet-type 12-LOX. We conclude that this type of transformation could occur naturally with the co-occurrence of LOX and cytochrome P450 or peroxygenase enzymes, and it could also contribute to the complexity of products formed in the autoxidation reactions of polyunsaturated fatty acids. PMID:25293588

  9. Leaching Behavior of Heavy Metals and Transformation of Their Speciation in Polluted Soil Receiving Simulated Acid Rain

    PubMed Central

    Zheng, Shun-an; Zheng, Xiangqun; Chen, Chun

    2012-01-01

    Heavy metals that leach from contaminated soils under acid rain are of increasing concern. In this study, simulated acid rain (SAR) was pumped through columns of artificially contaminated purple soil. Column leaching tests and sequential extraction were conducted for the heavy metals Cu, Pb, Cd, and Zn to determine the extent of their leaching as well as to examine the transformation of their speciation in the artificially contaminated soil columns. Results showed that the maximum leachate concentrations of Cu, Pb, Cd, and Zn were less than those specified in the Chinese Quality Standards for Groundwater (Grade IV), thereby suggesting that the heavy metals that leached from the polluted purple soil receiving acid rain may not pose as risks to water quality. Most of the Pb and Cd leachate concentrations were below their detection limits. By contrast, higher Cu and Zn leachate concentrations were found because they were released by the soil in larger amounts as compared with those of Pb and Cd. The differences in the Cu and Zn leachate concentrations between the controls (SAR at pH 5.6) and the treatments (SAR at pH 3.0 and 4.5) were significant. Similar trends were observed in the total leached amounts of Cu and Zn. The proportions of Cu, Pb, Cd, and Zn in the EXC and OX fractions were generally increased after the leaching experiment at three pH levels, whereas those of the RES, OM, and CAR fractions were slightly decreased. Acid rain favors the leaching of heavy metals from the contaminated purple soil and makes the heavy metal fractions become more labile. Moreover, a pH decrease from 5.6 to 3.0 significantly enhanced such effects. PMID:23185399

  10. Stereospecific enzymatic transformation of alpha-ketoglutarate to (2S,3R)-3-methyl glutamate during acidic lipopeptide biosynthesis.

    PubMed

    Mahlert, Christoph; Kopp, Florian; Thirlway, Jenny; Micklefield, Jason; Marahiel, Mohamed A

    2007-10-01

    The acidic lipopeptides, including the calcium-dependent antibiotics (CDA), daptomycin, and A54145, are important macrocyclic peptide natural products produced by Streptomyces species. All three compounds contain a 3-methyl glutamate (3-MeGlu) as the penultimate C-terminal residue, which is important for bioactivity. Here, biochemical in vitro reconstitution of the 3-MeGlu biosynthetic pathway is presented, using exclusively enzymes from the CDA producer Streptomyces coelicolor. It is shown that the predicted 3-MeGlu methyltransferase GlmT and its homologues DptI from the daptomycin producer Streptomyces roseosporus and LptI from the A54145 producer Streptomyces fradiae do not methylate free glutamic acid, PCP-bound glutamate, or Glu-containing CDA in vitro. Instead, GlmT, DptI, and LptI are S-adenosyl methionine (SAM)-dependent alpha-ketoglutarate methyltransferases that catalyze the stereospecific methylation of alpha-ketoglutarate (alphaKG) leading to (3R)-3-methyl-2-oxoglutarate. Subsequent enzyme screening identified the branched chain amino acid transaminase IlvE (SCO5523) as an efficient catalyst for the transformation of (3R)-3-methyl-2-oxoglutarate into (2S,3R)-3-MeGlu. Comparison of reversed-phase HPLC retention time of dabsylated 3-MeGlu generated by the coupled enzymatic reaction with dabsylated synthetic standards confirmed complete stereocontrol during enzymatic catalysis. This stereospecific two-step conversion of alphaKG to (2S,3R)-3-MeGlu completes our understanding of the biosynthesis and incorporation of beta-methylated amino acids into the nonribosomal lipopeptides. Finally, understanding this pathway may provide new possibilities for the production of modified peptides in engineered microbes. PMID:17784761

  11. Structural Transformation of Isolated Poplar and Switchgrass Lignins from Dilute Acid Pretreatment

    DOE PAGESBeta

    Sun, Qining; Pu, Yunqiao; Meng, Xianzhi; Wells, Tyrone; Ragauskas, Arthur J.

    2015-08-27

    A key step in conversion of cellulosic biomass into sustainable fuels and chemicals is thermochemical pretreatment to reduce plant cell wall recalcitrance. Obtaining an improved understanding of the fundamental chemistry of lignin, the most recalcitrant component of biomass, during pretreatment is critical to the continued development of renewable biofuel production. To examine the intrinsic chemistry of lignin during dilute acid pretreatment (DAP), lignin was isolated from poplar and switchgrass using a cellulolytic enzyme system and then treated under DAP conditions. These results highlight that lignin is subjected to depolymerization reactions within the first 2 min of dilute acid pretreatment andmore » these changes are accompanied by increased generation of aliphatic and phenolic hydroxyl groups of lignin. This is followed by a competing set of depolymerization and repolymerization reactions that lead to a decrease in the content of guaiacyl lignin units and an increase in condensed lignin units as the reaction residence time is extended beyond 5 min. Finally, we showed that a detailed comparison of changes in functional groups and molecular weights of cellulolytic enzyme lignins with different structural parameters, related to the recalcitrant properties of lignin, could be successfully altered during DAP conditions.« less

  12. Structural Transformation of Isolated Poplar and Switchgrass Lignins from Dilute Acid Pretreatment

    SciTech Connect

    Sun, Qining; Pu, Yunqiao; Meng, Xianzhi; Wells, Tyrone; Ragauskas, Arthur J.

    2015-08-27

    A key step in conversion of cellulosic biomass into sustainable fuels and chemicals is thermochemical pretreatment to reduce plant cell wall recalcitrance. Obtaining an improved understanding of the fundamental chemistry of lignin, the most recalcitrant component of biomass, during pretreatment is critical to the continued development of renewable biofuel production. To examine the intrinsic chemistry of lignin during dilute acid pretreatment (DAP), lignin was isolated from poplar and switchgrass using a cellulolytic enzyme system and then treated under DAP conditions. These results highlight that lignin is subjected to depolymerization reactions within the first 2 min of dilute acid pretreatment and these changes are accompanied by increased generation of aliphatic and phenolic hydroxyl groups of lignin. This is followed by a competing set of depolymerization and repolymerization reactions that lead to a decrease in the content of guaiacyl lignin units and an increase in condensed lignin units as the reaction residence time is extended beyond 5 min. Finally, we showed that a detailed comparison of changes in functional groups and molecular weights of cellulolytic enzyme lignins with different structural parameters, related to the recalcitrant properties of lignin, could be successfully altered during DAP conditions.

  13. Transformation of glutamate to. delta. -aminolevulinic acid by soluble extracts of Chlorobium vibrioforme

    SciTech Connect

    Rieble, S.; Ormerod, J.G.; Beale, S. )

    1989-07-01

    Formation of the tetrapyrrole pigment precursor {delta}-aminolevulinic acid (ALA) from glutamate was detected and partially characterized in extracts of the strictly anaerobic green photosynthetic bacterial species Chlorobium vibrioforme by using assay methods derived from those developed for algae and cyanobacteria. ALA formation in Chlorobium extracts was saturated at 10 mM glutamate and required NADPH and ATP at optimal concentrations of 0.3 and 3 mM, respectively. Preincubation of the enzyme extract with RNase A destroyed the ALA-forming activity completely. Activity in the RNase-treated extract was restored by supplementation with Chlorobium RNA after addition of RNasin to block further RNase action. RNA from the cyanobacterium Synechocystis sp. strain PCC 6803 and Escherichia coli tRNA{sup Glu} also restored activity. Activity was inhibited 50% by 0.2 {mu}M hemin. ALA formation was completely abolished by the addition of 5 {mu}M 3-amino-2,3-dihydrobenzoic acid (gabaculine). These results indicate that Chlorobium extracts share with those of plants, eucaryotic algae, cyanobacteria, prochlorophytes, and methanogens the capacity for RNA-dependent ALA formation from glutamate.

  14. Analytical evaluation of polyunsaturated fatty acids degradation during thermal oxidation of edible oils by Fourier transform infrared spectroscopy.

    PubMed

    Moya Moreno, M C; Mendoza Olivares, D; Amzquita Lpez, F J; Gimeno Adelantado, J V; Bosch Reig, F

    1999-09-13

    The oxidative deterioration of polyunsaturated fatty acids (PUFAs) in culinary oils and fats during episodes of heating associated with normal usage (80-300 degrees C, 20-40 min) has been monitored by Fourier transform infrared spectroscopy (FTIR). The thermal oxidation of PUFAs is a free radical chain reaction, in which hydroperoxides are generally recognized as the primary major products. Hydroperoxides of PUFAs are easily decomposed into a very complex mixture of secondary products with the decrease in unsaturation. The oxidative advance of PUFAs during heating was studied by the determination of unsaturation percentage at different temperatures and heating times. Oils frequently used in food frying such as olive oil, sunflower oil, corn oil and seeds oil (sunflower, safflower and canola seed) were studied. The results show there is a decrease in unsaturation starting at 150 degrees C and becoming more pronounced at temperatures around 250 degrees C. The following variations were found in the unsaturation percentage, expressed as methyl linoleate, between the original sample and the sample heated at 300 degrees C for 40 min: olive oil (19-6%), sunflower oil (29-12%), corn oil (28-18%) and seeds oil (23-11%). This variation in unsaturation grade provides evidence of the transformation of essential PUFAs and subsequent decrease in the oils' nutritional value. The internal standard method is suitably precise when the n-valeronitrile is used as standard as shown by the 1-2% relative standard deviation (R.S.D.) found for seven replicates. PMID:18967717

  15. Effect of crystalline form on phase transformation kinetics of poly(l-lactic acid)

    NASA Astrophysics Data System (ADS)

    Kalish, Jeffrey; Hsu, Shaw Ling

    2010-03-01

    Films of poly(l-lactic acid) (PLLA) were crystallized from the amorphous solid phase at various temperatures. At crystallization temperatures lower than 120^oC, the disordered alpha' phase appears, but at crystallization temperatures greater than 120^oC, the alpha crystal forms. Crystallization kinetics was followed using far infrared (FIR) spectroscopy. Vibrations in the FIR range can be used to directly assess the interchain interactions which are sensitive to changes in chain conformation. Interactions involving carbonyl and methyl functional groups have previously been observed in PLLA crystals. The relative rates of formation of the crystalline trans-gauche-trans conformation versus the interchain interactions were also investigated. Coexistence of the two crystalline forms has been investigated at crystallization temperatures near 120^oC. The alpha' crystalline form shows weaker interactions and lower thermal stability. By annealing at elevated temperatures, interchain interactions strengthened continuously.

  16. Measurements of deuterium quadrupole coupling in propiolic acid and fluorobenzenes using pulsed-beam Fourier transform microwave spectrometers

    SciTech Connect

    Sun, Ming; Sargus, Bryan A.; Carey, Spencer J.; Kukolich, Stephen G.

    2015-04-21

    The pure rotational spectra of deuterated propiolic acids (HCCCOOD and DCCCOOH), 1-fluorobenzene (4-d{sub 1}), and 1,2-difluorobenzene (4-d{sub 1}) in their ground states have been measured using two Fourier transform microwave (FTMW) spectrometers at the University of Arizona. For 1-fluorobenzene (4-d{sub 1}), nine hyperfine lines of three different ?J = 0 and 1 transitions were measured to check the synthesis method and resolution. For 1,2-difluorobenzene (4-d{sub 1}), we obtained 44 hyperfine transitions from 1 to 12 GHz, including 14 different ?J = 0, 1 transitions. Deuterium quadrupole coupling constants along the three principal inertia axes were well determined. For deuterated propiolic acids, 37 hyperfine lines of Pro-OD and 59 hyperfine lines of Pro-CD, covering 11 and 12 different ?J = ? 1, 0, 1 transitions, respectively, were obtained from 5 to 16 GHz. Deuterium quadrupole coupling constants along the three inertia axes were well resolved for Pro-OD. For Pro-CD, only eQq{sub aa} was determined due to the near coincidence of the CD bond and the least principal inertia axis. Some measurements were made using a newer FTMW spectrometer employing multiple free induction decays as well as background subtraction. For 1-fluorobenzene (4-d{sub 1}) and 1,2-difluorobenzene (4-d{sub 1}), a very large-cavity (1.2 m mirror dia.) spectrometer yielded very high resolution (2 kHz) spectra.

  17. Measurements of deuterium quadrupole coupling in propiolic acid and fluorobenzenes using pulsed-beam Fourier transform microwave spectrometers

    NASA Astrophysics Data System (ADS)

    Sun, Ming; Sargus, Bryan A.; Carey, Spencer J.; Kukolich, Stephen G.

    2015-04-01

    The pure rotational spectra of deuterated propiolic acids (HCCCOOD and DCCCOOH), 1-fluorobenzene (4-d1), and 1,2-difluorobenzene (4-d1) in their ground states have been measured using two Fourier transform microwave (FTMW) spectrometers at the University of Arizona. For 1-fluorobenzene (4-d1), nine hyperfine lines of three different ?J = 0 and 1 transitions were measured to check the synthesis method and resolution. For 1,2-difluorobenzene (4-d1), we obtained 44 hyperfine transitions from 1 to 12 GHz, including 14 different ?J = 0, 1 transitions. Deuterium quadrupole coupling constants along the three principal inertia axes were well determined. For deuterated propiolic acids, 37 hyperfine lines of Pro-OD and 59 hyperfine lines of Pro-CD, covering 11 and 12 different ?J = - 1, 0, 1 transitions, respectively, were obtained from 5 to 16 GHz. Deuterium quadrupole coupling constants along the three inertia axes were well resolved for Pro-OD. For Pro-CD, only eQqaa was determined due to the near coincidence of the CD bond and the least principal inertia axis. Some measurements were made using a newer FTMW spectrometer employing multiple free induction decays as well as background subtraction. For 1-fluorobenzene (4-d1) and 1,2-difluorobenzene (4-d1), a very large-cavity (1.2 m mirror dia.) spectrometer yielded very high resolution (2 kHz) spectra.

  18. Do soil Fe transformation and secretion of low-molecular-weight organic acids affect the availability of Cd to rice?

    PubMed

    Chen, Xue; Yang, Yazhou; Liu, Danqing; Zhang, Chunhua; Ge, Ying

    2015-12-01

    The bioavailability of cadmium (Cd) to rice may be complicated by chemical and biological factors in the rhizosphere. The aim of this work is to investigate how soil iron (Fe) redox transformations and low-molecular-weight organic acid (LMWOA) exudation from root affect Cd accumulation in rice. Two soils (a paddy soil and a saline soil) with different physicochemical properties were used in this study. Soil redox conditions were changed by flooding and addition of organic matter (OM). Two days after the soil treatments, rice seedlings were transplanted in a vermiculite-soil system and grown for 10days. We measured pH and Eh, LMWOA, Fe and Cd contents in rice, and their fractions in the soils and vermiculite. Cadmium accumulation in rice declined in both soils upon the flooding and OM treatment. Iron dissolution in the paddy soil and its deposition in the rhizosphere significantly increased upon the OM addition, but the concentration of Fe plaque on the rice root significantly declined. Conversely, although Fe transformed into less active fractions in the saline soil, Fe accumulation on the surface and in the tissue of root was considerably enhanced. The secretion of LMWOA was remarkably induced when the OM was amended in the saline soil, but the same effect was not observed in the paddy soil. Reduction of Cd uptake by rice could be attributed to different factors in the two soils. For the paddy soil, the lowered Cd bioavailability was likely due to the competition of Fe and Cd for the binding sites on the vermiculite surface. For the saline soil, however, rice responded to the low Fe mobility through more LMWOA exudation and Fe plaque formation, and their increases could explain the decrease of rice Cd. PMID:26260840

  19. A PHENYLPROPENOIC ACID DERIVATIVE, N-CAFFEOLYTYRAMINE, IS A POTENT PHYTOCHEMICAL TO INDUCE APOPTOSIS OF HUMAN TRANSFORMED MYEOLOCYTIC U937 AND HL-60 AND LYMPHOCYTIC JURKAT CELLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Phytochemicals consist of many diverse compounds which may have beneficial effects on chronic diseases such as diabetes, heart disease, and cancers. Previously, a phenylpropenoic acid derivative, N-coumaroyltyramine, was reported to arrest human transformed cells at S-phase of the cell cycle by inhi...

  20. Cleft lip with or without cleft palate: Associations with transforming growth factor alpha and retinoic acid receptor loci

    SciTech Connect

    Chenevix-Trench, G.; Jones, K. Univ. of Queensland ); Green, A.C.; Duffy, D.L.; Martin, N.G. )

    1992-12-01

    The first association study of cleft lip with or without cleft palate (CL/P), with candidate genes, found an association with the transforming growth-factor alpha (TGFA) locus. This finding has since been replicated, in whole or in part, in three independent studies. Here the authors extend their original analysis of the TGFA TaqI RFLP to two other TGFA RFLPs and seven other RFLPs at five candidate genes in 117 nonsyndromic cases of CL/P and 113 controls. The other candidate genes were the retinoic acid receptor (RARA), the bcl-2 oncogene, and the homeobox genes 2F, 2G, and EN2. Significant associations with the TGFA TaqI and BamHI RFLPs were confirmed, although associations of clefting with previously reported haplotypes did not reach significance. Of particular interest, in view of the known teratogenic role of retinoic acid, was a significant association with the RARA PstI RFLP (P = .016; not corrected for multiple testing). The effect on risk of the A2 allele appears to be additive, and although the A2A2 homozygote only has an odds ratio of about 2 and recurrence risk to first-degree relatives ([lambda][sub 1]) of 1.06, because it is so common it may account for as much as a third of the attributable risk of clefting. There is no evidence of interaction between the TGFA and RARA polymorphisms on risk, and jointly they appear to account for almost half the attributable risk of clefting. 43 refs., 1 fig., 4 tabs.

  1. Interference of humic acids and DNA extracted directly from soil in detection and transformation of recombinant DNA from bacteria and a yeast.

    PubMed

    Tebbe, C C; Vahjen, W

    1993-08-01

    A two-step protocol for the extraction and purification of total DNA from soil samples was developed. Crude DNA extracts (100 microliters from 5 g of soil) were contaminated with humic acids at concentrations of 0.7 to 3.3 micrograms/microliters, depending on the type of soil extracted. The coextracted humic acid fraction of a clay silt was similar to a commercially available standard humic acid mixture, as determined by electrophoretic mobility in agarose gels, UV fluorescence, and inhibition assays with DNA-transforming enzymes. Restriction endonucleases were inhibited at humic acid concentrations of 0.5 to 17.2 micrograms/ml for the commercial product and 0.8 to 51.7 micrograms/ml for the coextracted humic acids. DNase I was less susceptible (MIC of standard humic acids, 912 micrograms/ml), and RNase could not be inhibited at all (MIC, > 7.6 mg/ml). High inhibitory susceptibilities for humic acids were observed with Taq polymerase. For three Taq polymerases from different commercial sources, MICs were 0.08 to 0.64 micrograms of the standard humic acids per ml and 0.24 to 0.48 micrograms of the coextracted humic acids per ml. The addition of T4 gene 32 protein increased the MIC for one Taq polymerase to 5.12 micrograms/ml. Humic acids decreased nonradioactive detection in DNA-DNA slot blot hybridizations at amounts of 0.1 micrograms and inhibited transformation of competent Escherichia coli HB101 with a broad-host-range plasmid, pUN1, at concentrations of 100 micrograms/ml. Purification of crude DNA with ion-exchange chromatography resulted in removal of 97% of the initially coextracted humic acids.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7690221

  2. The transforming acidic coiled coil 3 protein is essential for spindle-dependent chromosome alignment and mitotic survival.

    PubMed

    Schneider, Leonid; Essmann, Frank; Kletke, Anja; Rio, Paula; Hanenberg, Helmut; Wetzel, Wiebke; Schulze-Osthoff, Klaus; Nürnberg, Bernd; Piekorz, Roland P

    2007-10-01

    Cancer-associated centrosomal transforming acidic coiled coil (TACC) proteins are involved in mitotic spindle function. By employing gene targeting, we have recently described a nonredundant and essential role of TACC3 in regulating cell proliferation. In this study, we used an inducible RNA interference approach to characterize the molecular function of TACC3 and its role in mitotic progression and cell survival. Our data demonstrate that a TACC3 knockdown arrests G(1) checkpoint-compromised HeLa cells prior to anaphase with aberrant spindle morphology and severely misaligned chromosomes. Interestingly, TACC3-depleted cells fail to accumulate the mitotic kinase Aurora B and the checkpoint protein BubR1 to normal levels at kinetochores. Moreover, localization of the structural protein Ndc80 at outer kinetochores is reduced, indicating a defective kinetochore-microtubule attachment in TACC3-deficient cells. As a consequence of prolonged TACC3 depletion, cells undergo caspase-dependent cell death that relies on a spindle checkpoint-dependent mitotic arrest. TACC3 knockdown cells that escape from this arrest by mitotic slippage become highly polyploid and accumulate supernumerary centrosomes. Similarly, deficiency of the post-mitotic cell cycle inhibitor p21(WAF) exacerbates the effects of TACC3 depletion. Our findings therefore point to an essential role of TACC3 in spindle assembly and cellular survival and identify TACC3 as a potential therapeutic target in cancer cells. PMID:17675670

  3. Direct determination of rosmarinic acid in Lamiaceae herbs using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and chemometrics.

    PubMed

    Saltas, Dimitrios; Pappas, Christos S; Daferera, Dimitra; Tarantilis, Petros A; Polissiou, Moschos G

    2013-04-01

    For the determination of rosmarinic acid (RA) directly in pulverized plant material, a method is developed using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) without any physicochemical pretreatment of samples. The RA content of 11 samples of eight different Lamiaceae herbs, as determined by high performance liquid chromatography (HPLC), varied between 86 1 mg/g (in lemon balm) and 12.0 0.8 mg/g (in hyssop) of dried plant material. The 11 samples and 50 other additional samples, which were prepared by mixing initial samples with KBr, were measured using DRIFTS. The second derivative of the spectral region 1344-806 cm(-1) was used and the corresponding data were analyzed using partial least squares (PLS) regression. The correlation between infrared spectral analysis and HPLC measurements shows that the DRIFTS method is sufficiently accurate, simple, and rapid. The RA content of the 11 Lamiaceae samples determined by DRIFTS ranged from 81 4 mg/g (in lemon balm) to 12 3 mg/g (in hyssop) of dried plant material. PMID:23496773

  4. Phosphorus and Silicon Analogs of Isocyanic Acid: Fourier-Transform Microwave Spectroscopy of Hpco and HNSiO

    NASA Astrophysics Data System (ADS)

    Thorwirth, Sven; Lattanzi, Valerio; McCarthy, Michael C.

    2014-06-01

    By means of Fourier transform microwave spectroscopy of a supersonic jet, the pure rotational spectra of two second-row analogs to isocyanic acid, HNCO, have been observed for the first time. The phosphorus and silicon analogs HPCO and HNSiO, respectively, were observed by their fundamental a-type rotational transitions (?a(HPCO)= 0.45 D, ?a(HNSiO)= 2.10 D) in the centimeter wave range from 10 to 32 GHz through discharges of appropriate precursor gases highly diluted in neon. Spectroscopic searches and identification were based on predictions from high-level quantum-chemical calculations at the CCSD(T) level of theory in combination with large basis sets. Excellent agreement between experimental and calculated molecular parameters is found. In case of HPCO, the 13C isotopic species was also observed. Since both the stem compound HNCO and its sulphur analog HNCS are known to be present in space, and because also a sizable number of phosphorus and silicon-bearing species were detected there, both compounds are plausible targets for future radio astronomical searches using sensitive radio astronomical instrumentation.

  5. Effects of short-term acid and aluminum exposure on the parr-smolt transformation in Atlantic salmon (Salmo salar): Disruption of seawater tolerance and endocrine status

    USGS Publications Warehouse

    Monette, M.Y.; Bjornsson, Bjorn Thrandur; McCormick, S.D.

    2008-01-01

    Episodic acidification resulting in increased acidity and inorganic aluminum (Ali) is known to interfere with the parr-smolt transformation of Atlantic salmon (Salmo salar), and has been implicated as a possible cause of population decline. To determine the extent and mechanism(s) by which short-term acid/Al exposure compromises smolt development, Atlantic salmon smolts were exposed to either control (pH 6.7-6.9) or acid/Al (pH 5.4-6.3, 28-64 ??g l-1 Ali) conditions for 2 and 5 days, and impacts on freshwater (FW) ion regulation, seawater (SW) tolerance, plasma hormone levels and stress response were examined. Gill Al concentrations were elevated in all smolts exposed to acid/Al relative to controls confirming exposure to increased Ali. There was no effect of acid/Al on plasma ion concentrations in FW however, smolts exposed to acid/Al followed by a 24 h SW challenge exhibited greater plasma Cl- levels than controls, indicating reduced SW tolerance. Loss of SW tolerance was accompanied by reductions in gill Na+,K+-ATPase (NKA) activity and Na+,K+,2Cl- (NKCC) cotransporter protein abundance. Acid/Al exposure resulted in decreased plasma insulin-like growth factor (IGF-I) and 3,3???,5???-triiodo-l-thyronine (T3) levels, whereas no effect of treatment was seen on plasma cortisol, growth hormone (GH), or thyroxine (T4) levels. Acid/Al exposure resulted in increased hematocrit and plasma glucose levels in FW, but both returned to control levels after 24 h in SW. The results indicate that smolt development and SW tolerance are compromised by short-term exposure to acid/Al in the absence of detectable impacts on FW ion regulation. Loss of SW tolerance during short-term acid/Al exposure likely results from reductions in gill NKA and NKCC, possibly mediated by decreases in plasma IGF-I and T3. ?? 2008 Elsevier Inc.

  6. Better rooting procedure to enhance survival rate of field grown malaysian eksotika papaya transformed with 1-aminocyclopropane-1-carboxylic Acid oxidase gene.

    PubMed

    Sekeli, Rogayah; Abdullah, Janna Ong; Namasivayam, Parameswari; Muda, Pauziah; Abu Bakar, Umi Kalsom

    2013-01-01

    A high survival rate for transformed papaya plants when transferred to the field is useful in the quest for improving the commercial quality traits. We report in this paper an improved rooting method for the production of transformed Malaysian Eksotika papaya with high survival rate when transferred to the field. Shoots were regenerated from embryogenic calli transformed with antisense and RNAi constructs of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) genes using the Agrobacterium tumefaciens-mediated transformation method. Regenerated transformed shoots, each measuring approximately 3-4 cm in height, were cultured in liquid half-strength Murashige and Skoog (MS) medium or sterile distilled water, and with either perlite or vermiculite supplementation. All the culturing processes were conducted either under sterile or nonsterile condition. The results showed that rooting under sterile condition was better. Shoots cultured in half-strength MS medium supplemented with vermiculite exhibited a 92.5% rooting efficiency while perlite showed 77.5%. The survival rate of the vermiculite-grown transformed papaya plantlets after transfer into soil, contained in polybags, was 94%, and the rate after transfer into the ground was 92%. Morpho-histological analyses revealed that the tap roots were more compact, which might have contributed to the high survival rates of the plantlets. PMID:25969786

  7. Better Rooting Procedure to Enhance Survival Rate of Field Grown Malaysian Eksotika Papaya Transformed with 1-Aminocyclopropane-1-Carboxylic Acid Oxidase Gene

    PubMed Central

    Sekeli, Rogayah; Abdullah, Janna Ong; Namasivayam, Parameswari; Muda, Pauziah; Abu Bakar, Umi Kalsom

    2013-01-01

    A high survival rate for transformed papaya plants when transferred to the field is useful in the quest for improving the commercial quality traits. We report in this paper an improved rooting method for the production of transformed Malaysian Eksotika papaya with high survival rate when transferred to the field. Shoots were regenerated from embryogenic calli transformed with antisense and RNAi constructs of 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) genes using the Agrobacterium tumefaciens-mediated transformation method. Regenerated transformed shoots, each measuring approximately 3-4?cm in height, were cultured in liquid half-strength Murashige and Skoog (MS) medium or sterile distilled water, and with either perlite or vermiculite supplementation. All the culturing processes were conducted either under sterile or nonsterile condition. The results showed that rooting under sterile condition was better. Shoots cultured in half-strength MS medium supplemented with vermiculite exhibited a 92.5% rooting efficiency while perlite showed 77.5%. The survival rate of the vermiculite-grown transformed papaya plantlets after transfer into soil, contained in polybags, was 94%, and the rate after transfer into the ground was 92%. Morpho-histological analyses revealed that the tap roots were more compact, which might have contributed to the high survival rates of the plantlets. PMID:25969786

  8. Characterization of the chemical composition of soil humic acids using Fourier transform ion cyclotron resonance mass spectrometry

    NASA Astrophysics Data System (ADS)

    Ikeya, Kosuke; Sleighter, Rachel L.; Hatcher, Patrick G.; Watanabe, Akira

    2015-03-01

    The composition of humic acids (HAs) with varying degrees of humification isolated from 10 common Japanese soils was characterized using negative ion mode electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry at 12 T. In particular, attention was paid to polynuclear aromatic components, which are more associated with the refractory nature of HAs and their resistance to biodegradation in soil than single C ring aromatic entities, such as lignin-like components, and aliphatic functionalities. Thousands of peaks were observed in the m/z range of 200-700, and molecular formulas were assigned to 817-2457 peaks in each sample. The molecular formulas having H/C and O/C ratios similar to those of lipid, protein, and other aliphatics with low double bond equivalents (DBE) of 0-7 were generally observed across the m/z range of 200-700. Although there were a number of molecular formulas having H/C and O/C values similar to those of lignin across the wide m/z range in the HAs with a low degree of humification, most lignin-like molecular formulas in the larger m/z range (450-650) or irrespective of m/z were lacking in the HAs with middle and high degrees of humification, respectively. These observations suggest a longer residence time for lignin monomers/dimers (and their derivatives; m/z 200-400) than larger lignin oligomers (m/z 450-650) in HA structural domains. The number of molecular formulas having H/C and O/C values similar to condensed aromatics increased with increasing degree of humification. The m/z and DBE values of condensed aromatic-like molecular formulas in the HAs with a lower degree of humification were <500 and 10-25, respectively, whilst the ranges expanded to 600 and 30-33, respectively, in the highly-humified black HAs. Kendrick mass defect analysis using a carboxyl group as the characteristic functional group found that 31, 73, and 39 molecular formulas had chain-type, net-type, and biphenyl-type condensed aromatic acids, respectively, as possible structures. Summed peak magnitudes of the condensed aromatic-like molecular formulas, in particular those with higher DBE values (>17) expected to have at least 5 rings, increased with increasing degree of humification and aromatic C content (evaluated by solid-state 13C nuclear magnetic resonance spectroscopy), suggesting their contribution to the intrinsic recalcitrance of HAs in soil.

  9. The impact of mineral fertilizers and lime on the transformation of humic acids in a soddy-podzolic heavy loamy soil of the Cis-Ural region

    NASA Astrophysics Data System (ADS)

    Zav'yalova, N. E.

    2015-06-01

    The composition and structure of humic acids in a soddy-podzolic heavy loamy soil (Retisol) of the Cis-Ural region after the long-term application of mineral fertilizers and lime was studied by the methods of elemental analysis, infrared spectroscopy, and thermogravimetry. It was found that mineral fertilizers and lime did not change the ranges of C, H, O, and N contents and general structure typical of humic acids in soddy-podzolic soils. The long-term anthropogenic impact on the soil resulted in some transformation of the composition and properties of humic acids. Clear absorption bands in the area of 1700 cm-1 (C=O of carbonyl group) and 1620 cm-1 (C=C of aromatic rings), which characterize the benzenoid structures of molecules, were found in the infrared spectra of humic acids from the soil treated with lime at the rate to compensate for the total acidity. Soil liming favored the accumulation of thermodynamically stable fragments of the central part of humic acid molecules and the destruction of peripheral radicals. The application of mineral fertilizers resulted in the enrichment of humic acids with aliphatic fragments. The combined application of mineral fertilizers and lime increased the portion of aromatic structures and, at the same time, enriched humic acids in aliphatic fragments less resistant to pyrolysis. These fragments are biologically and chemically active and can be readily involved in the element turnover processes, thus protecting the stable part of humus from the biological destruction.

  10. Ambient formic acid in southern California air: A comparison of two methods, Fourier transform infrared spectroscopy and alkaline trap-liquid chromatography with UV detection

    SciTech Connect

    Grosjean, D. ); Tuazon, E.C. ); Fujita, E. )

    1990-01-01

    Formic acid is an ubiquitous component of urban smog. Sources of formic acid in urban air include direct emissions from vehicles and in situ reaction of ozone with olefins. Ambient levels of formic acid in southern California air were first measured some 15 years ago by Hanst et al. using long-path Fourier transform infrared spectroscopy (FTIR). All subsequent studies of formic acid in the Los Angeles area have involved the use of two methods, either FTIR or collection on alkaline traps followed by gas chromatography, ion chromatography, or liquid chromatography analysis with UV detection, ATLC-UV. The Carbon Species Methods Comparison Study (CSMCS), a multilaboratory air quality study carried out in August 1986 at a southern California smog receptor site, provided an opportunity for direct field comparison of the FTIR and alkaline trap methods. The results of the comparison are presented in this brief report.

  11. Stability of pathogenic colony types of Neisseria gonorrhoeae in liquid culture by using the parameters of colonial morphology and deoxyribonucleic acid transformation.

    PubMed Central

    La Scolea, L J; Dul, M J; Young, F E

    1975-01-01

    This investigation describes the surveillance of the colonial stability of the pathogenic type 1 from the gonococcal strain F62 to the nonvirulent types 3 and 4 in different liquid media. The maintenance of the colony types was monitored by the parameters of colonial morphology and deoxyribonucleic acid-mediated transformation. During growth in a complex medium, Mueller-Hinton broth, only 46.7% of the gonococcal population remained as type 1 after 12 h. The greatest change in the type 1 colony-forming units correlated with the decline in viable count. The conversion process could not be prevented by the continual maintenance of the gonococcus in logarithmic growth. The frequency of transformation from PRO(minus) (proline) to PRO(plus) was proportional to this decrease in type 1 colony-forming units. In contrast to Mueller-Hinton medium, the chemically defined minimal medium Gonococcal Genetic Medium (GGM) was capable of maintaining approximately 90% of the gonococcal population in the type 1 colonial form after 16 h of growth, despite a decrease in the viable count. Although the percentage of type 1 appeared to remain constant in GGM, the apparent transformation frequency increased approximately 24-fold from 0 to 12 h of growth. GGM appears to stimulate or maintain competence, as evidenced by an eightfold increase in transformation when cells are exposed to deoxyribonucleic acid in GGM as compared to Mueller-Hinton. PMID:809469

  12. Component analyses of urinary nanocrystallites of uric acid stone formers by combination of high-resolution transmission electron microscopy, fast Fourier transformation, energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared spectroscopy.

    PubMed

    Sun, Xin-Yuan; Xue, Jun-Fa; Xia, Zhi-Yue; Ouyang, Jian-Ming

    2015-06-01

    This study aimed to analyse the components of nanocrystallites in urines of patients with uric acid (UA) stones. X-ray diffraction (XRD), Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy (HRTEM), fast Fourier transformation (FFT) of HRTEM, and energy dispersive X-ray spectroscopy (EDS) were performed to analyse the components of these nanocrystallites. XRD and FFT showed that the main component of urinary nanocrystallites was UA, which contains a small amount of calcium oxalate monohydrate and phosphates. EDS showed the characteristic absorption peaks of C, O, Ca and P. The formation of UA stones was closely related to a large number of UA nanocrystallites in urine. A combination of HRTEM, FFT, EDS and XRD analyses could be performed accurately to analyse the components of urinary nanocrystallites. PMID:26023155

  13. K3LaTe2O9: a new alkali-rare earth tellurate with face-sharing TeO6 octahedra.

    PubMed

    Zhang, Xinyuan; Yao, Jiyong; Jiang, Xingxing; Fu, Ying; Lin, Zheshuai; Zhang, Guochun; Wu, Yicheng

    2015-09-21

    A new quaternary alkali-lanthanide metal tellurate K3LaTe2O9 has been synthesized by a conventional high-temperature solid state method, and single crystals have been grown by spontaneous crystallization. K3LaTe2O9 crystallizes in the hexagonal space group P63/mmc, with a = b = 6.0589(9) Å, c = 15.024(3) Å, and Z = 2. In the structure, [Te2O9](6-) contains rare face-sharing TeO6 polyhedra, which are connected by LaO6 octahedra forming a three-dimensional framework structure. Furthermore, its properties are investigated by UV-vis-NIR diffuse reflectance spectroscopy, Raman and IR spectroscopy, thermal analysis, variable-temperature X-ray powder diffraction, and first-principles calculations. PMID:26242776

  14. Using radiative transfer models to study the atmospheric water vapor content and to eliminate telluric lines from high-resolution optical spectra

    NASA Astrophysics Data System (ADS)

    Gardini, A.; Maz Apellniz, J.; Prez, E.; Quesada, J. A.; Funke, B.

    2013-05-01

    The Radiative Transfer Model (RTM) and the retrieval algorithm, incorporated in the SCIATRAN 2.2 software package developed at the Institute of Remote Sensing/Institute of Enviromental Physics of Bremen University (Germany), allows to simulate, among other things, radiance/irradiance spectra in the 2400--24 000 range. In this work we present applications of RTM to two case studies. In the first case the RTM was used to simulate direct solar irradiance spectra, with different water vapor amounts, for the study of the water vapor content in the atmosphere above Sierra Nevada Observatory. Simulated spectra were compared with those measured with a spectrometer operating in the 8000--10 000 range. In the second case the RTM was used to generate telluric model spectra to subtract the atmospheric contribution and correct high-resolution stellar spectra from atmospheric water vapor and oxygen lines. The results of both studies are discussed.

  15. Fourier Transform Near-Infrared Spectroscopy for rapid and simple determination of phytic acid content in green gram seeds (Vigna radiata).

    PubMed

    Pande, Ranjana; Mishra, H N

    2015-04-01

    The feasibility of measuring phytic acid content in green gram (Vigna radiata) seeds was investigated by Fourier Transform Near-Infrared (FT-NIR) spectroscopic technique. Pure phytic acid standards of varying concentrations were scanned using FTNIR spectroscopy. The spectra were measured in diffused reflectance mode by keeping 100-1500 mg/100g standard of pure phytic acid in small sample cuvette. A calibration model was developed using pure phytic acid standards of varying concentrations in the near-infrared region (4000-12,000 cm(-1)). FT-NIR spectroscopy with chemometrics, using the first derivative plus vector normalisation method could predict the phytic acid content in green gram seeds samples. The developed model was validated using cross-validation technique. Maximum coefficient of determination (R(2)) value of 0.97 was obtained for the calibration model developed. The developed model was applied to predict phytic acid content in green gram seeds samples within 1-2 min. The developed procedure was further validated by recovery studies by comparing with UV spectroscopic method of phytic acid determination. PMID:25442633

  16. Development of a Nuclear Transformation System for Oleaginous Green Alga Lobosphaera (Parietochloris) incisa and Genetic Complementation of a Mutant Strain, Deficient in Arachidonic Acid Biosynthesis

    PubMed Central

    Khozin-Goldberg, Inna; Leu, Stefan; Shapira, Michal; Kaye, Yuval; Tourasse, Nicolas; Vallon, Olivier; Boussiba, Sammy

    2014-01-01

    Microalgae are considered a promising source for various high value products, such as carotenoids, ω-3 and ω-6 polyunsaturated fatty acids (PUFA). The unicellular green alga Lobosphaera (Parietochloris) incisa is an outstanding candidate for the efficient phototrophic production of arachidonic acid (AA), an essential ω-6 PUFA for infant brain development and a widely used ingredient in the baby formula industry. Although phototrophic production of such algal products has not yet been established, estimated costs are considered to be 2–5 times higher than competing heterotrophic production costs. This alga accumulates unprecedented amounts of AA within triacylglycerols and the molecular pathway of AA biosynthesis in L. incisa has been previously elucidated. Thus, progress in transformation and metabolic engineering of this high value alga could be exploited for increasing the efficient production of AA at competitive prices. We describe here the first successful transformation of L. incisa using the ble gene as a selection marker, under the control of the endogenous RBCS promoter. Furthermore, we have succeeded in the functional complementation of the L. incisa mutant strain P127, containing a mutated, inactive version of the delta-5 (Δ5) fatty acid desaturase gene. A copy of the functional Δ5 desaturase gene, linked to the ble selection marker, was transformed into the P127 mutant. The resulting transformants selected for zeocine resistant, had AA biosynthesis partially restored, indicating the functional complementation of the mutant strain with the wild-type gene. The results of this study present a platform for the successful genetic engineering of L. incisa and its long-chain PUFA metabolism. PMID:25133787

  17. Oxalic acid in clear and cloudy atmospheres: Analysis of data from International Consortium for Atmospheric Research on Transport and Transformation 2004

    NASA Astrophysics Data System (ADS)

    Sorooshian, Armin; Varutbangkul, Varuntida; Brechtel, Fred J.; Ervens, Barbara; Feingold, Graham; Bahreini, Roya; Murphy, Shane M.; Holloway, John S.; Atlas, Elliot L.; Buzorius, Gintas; Jonsson, Haflidi; Flagan, Richard C.; Seinfeld, John H.

    2006-12-01

    Oxalic acid is often the leading contributor to the total dicarboxylic acid mass in ambient organic aerosol particles. During the 2004 International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) field campaign, nine inorganic ions (including SO42-) and five organic acid ions (including oxalate) were measured on board the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter research aircraft by a particle-into-liquid sampler (PILS) during flights over Ohio and surrounding areas. Five local atmospheric conditions were studied: (1) cloud-free air, (2) power plant plume in cloud-free air with precipitation from scattered clouds overhead, (3) power plant plume in cloud-free air, (4) power plant plume in cloud, and (5) clouds uninfluenced by local pollution sources. The aircraft sampled from two inlets: a counterflow virtual impactor (CVI) to isolate droplet residuals in clouds and a second inlet for sampling total aerosol. A strong correlation was observed between oxalate and SO42- when sampling through both inlets in clouds. Predictions from a chemical cloud parcel model considering the aqueous-phase production of dicarboxylic acids and SO42- show good agreement for the relative magnitude of SO42- and oxalate growth for two scenarios: power plant plume in clouds and clouds uninfluenced by local pollution sources. The relative contributions of the two aqueous-phase routes responsible for oxalic acid formation were examined; the oxidation of glyoxylic acid was predicted to dominate over the decay of longer-chain dicarboxylic acids. Clear evidence is presented for aqueous-phase oxalic acid production as the primary mechanism for oxalic acid formation in ambient aerosols.

  18. In situ fourier transform infrared study of crotyl alcohol, maleic acid, crotonic acid, and maleic anhydride oxidation on a V-P-O industrial catalyst

    SciTech Connect

    Wenig, R.W.; Schrader, G.L.

    1987-10-22

    Crotyl alcohol, maleic acid, crotonic (2-butenoic) acid, and maleic anhydride were fed to an in situ infrared cell at 300/sup 0/C containing a P/V = 1.1 vanadium-phosphorous-oxide (V-P-O) catalyst used for the selective oxidation of n-butane. Crotyl alcohol was used as a mechanistic probe for the formation of reactive olefin species observed during previous n-butane and 1-butene studies. Crotonic acid, maleic acid, and maleic anhydride were fed as probes for the existence of other possible adsorbed intermediates. Olefin species and maleic acid are proposed as possible reaction intermediates in n-butane selective oxidation to maleic anhydride. The involvement of peroxide species in the oxidation of butadiene to maleic acid is also discussed.

  19. Evidence for an Ionic Intermediate in the Transformation of Fatty Acid Hydroperoxide by a Catalase-related Allene Oxide Synthase from the Cyanobacterium Acaryochloris marina*

    PubMed Central

    Gao, Benlian; Boeglin, William E.; Zheng, Yuxiang; Schneider, Claus; Brash, Alan R.

    2009-01-01

    Allene oxides are reactive epoxides biosynthesized from fatty acid hydroperoxides by specialized cytochrome P450s or by catalase-related hemoproteins. Here we cloned, expressed, and characterized a gene encoding a lipoxygenase-catalase/peroxidase fusion protein from Acaryochloris marina. We identified novel allene oxide synthase (AOS) activity and a by-product that provides evidence of the reaction mechanism. The fatty acids 18.4ω3 and 18.3ω3 are oxygenated to the 12R-hydroperoxide by the lipoxygenase domain and converted to the corresponding 12R,13-epoxy allene oxide by the catalase-related domain. Linoleic acid is oxygenated to its 9R-hydroperoxide and then, surprisingly, converted ∼70% to an epoxyalcohol identified spectroscopically and by chemical synthesis as 9R,10S-epoxy-13S-hydroxyoctadeca-11E-enoic acid and only ∼30% to the 9R,10-epoxy allene oxide. Experiments using oxygen-18-labeled 9R-hydroperoxide substrate and enzyme incubations conducted in H218O indicated that ∼72% of the oxygen in the epoxyalcohol 13S-hydroxyl arises from water, a finding that points to an ionic intermediate (epoxy allylic carbocation) during catalysis. AOS and epoxyalcohol synthase activities are mechanistically related, with a reacting intermediate undergoing a net hydrogen abstraction or hydroxylation, respectively. The existence of epoxy allylic carbocations in fatty acid transformations is widely implicated although for AOS reactions, without direct experimental support. Our findings place together in strong association the reactions of allene oxide synthesis and an ionic reaction intermediate in the AOS-catalyzed transformation. PMID:19531485

  20. A Well-Defined Aluminum-Based Lewis Acid as an Effective Catalyst for Diels-Alder Transformations.

    PubMed

    Liu, Zhizhou; Lee, Jazreen Hui Qi; Ganguly, Rakesh; Vidovi?, Dragoslav

    2015-08-01

    A catalytically active aluminum-based system for Diels-Alder transformations is reported. The system was generated by mixing a ?-diketiminate-stabilized aluminum bistriflate compound with Na[BAr(Cl) 4 (Ar(Cl) =3,5-Cl2 C6 H3). Solid-state analysis of the catalytic system reveals a unique structure incorporating a two-dimensional coordination polymer. According to the experimental results obtained from several Diels-Alder transformations, the aluminum-based system appears to be a more practical and more robust alternative to the recently reported compounds based on carbon and silicon cations. PMID:26121664

  1. Transformational Learners: Transformational Teachers

    ERIC Educational Resources Information Center

    Jones, Marguerite

    2009-01-01

    Transformational learning, according to Mezirow (1981), involves transforming taken-for-granted frames of reference into more discriminating, flexible "habits of mind". In teacher education, transformative learning impacts on the development of students' action theories, self-efficacy and professional attributes. Although considered imperative to

  2. Chemical and physical transformations of aluminosilicate clay minerals due to acid treatment and consequences for heterogeneous ice nucleation.

    PubMed

    Sihvonen, Sarah K; Schill, Gregory P; Lyktey, Nicholas A; Veghte, Daniel P; Tolbert, Margaret A; Freedman, Miriam Arak

    2014-09-25

    Mineral dust aerosol is one of the largest contributors to global ice nuclei, but physical and chemical processing of dust during atmospheric transport can alter its ice nucleation activity. In particular, several recent studies have noted that sulfuric and nitric acids inhibit heterogeneous ice nucleation in the regime below liquid water saturation in aluminosilicate clay minerals. We have exposed kaolinite, KGa-1b and KGa-2, and montmorillonite, STx-1b and SWy-2, to aqueous sulfuric and nitric acid to determine the physical and chemical changes that are responsible for the observed deactivation. To characterize the changes to the samples upon acid treatment, we use X-ray diffraction, transmission electron microscopy, and inductively coupled plasma-atomic emission spectroscopy. We find that the reaction of kaolinite and montmorillonite with aqueous sulfuric acid results in the formation of hydrated aluminum sulfate. In addition, sulfuric and nitric acids induce large structural changes in montmorillonite. We additionally report the supersaturation with respect to ice required for the onset of ice nucleation for these acid-treated species. On the basis of lattice spacing arguments, we explain how the chemical and physical changes observed upon acid treatment could lead to the observed reduction in ice nucleation activity. PMID:25211030

  3. Improvement of Polyunsaturated Fatty Acid Production in Echium acanthocarpum Transformed Hairy Root Cultures by Application of Different Abiotic Stress Conditions

    PubMed Central

    Zárate, Rafael; Cequier-Sánchez, Elena; Rodríguez, Covadonga; Dorta-Guerra, Roberto; El Jaber-Vazdekis, Nabil; Ravelo, Ángel G.

    2013-01-01

    Fatty acids are of great nutritional, therapeutic, and physiological importance, especially the polyunsaturated n-3 fatty acids, possessing larger carbon chains and abundant double bonds or their immediate precursors. A few higher plant species are able to accumulate these compounds, like those belonging to the Echium genus. Here, the novel E. acanthocarpum hairy root system, which is able to accumulate many fatty acids, including stearidonic and α-linolenic acids, was optimized for a better production. The application of abiotic stress resulted in larger yields of stearidonic and α-linolenic acids, 60 and 35%, respectively, with a decrease in linoleic acid, when grown in a nutrient medium consisting of B5 basal salts, sucrose or glucose, and, more importantly, at a temperature of 15°C. The application of osmotic stress employing sorbitol showed no positive influence on the fatty acid yields; furthermore, the combination of a lower culture temperature and glucose did not show a cumulative boosting effect on the yield, although this carbon source was similarly attractive. The abiotic stress also influenced the lipid profile of the cultures, significantly increasing the phosphatidylglycerol fraction but not the total lipid neither their biomass, proving the appropriateness of applying various abiotic stress in this culture to achieve larger yields. PMID:25937970

  4. Lactic Acid is Elevated in Idiopathic Pulmonary Fibrosis and Induces Myofibroblast Differentiation Via pH-Dependent Activation of Transforming Growth Factor-β

    SciTech Connect

    Kottman, R. M.; Kulkarni, Ajit A.; Smolnycki, Katie A.; Lyda, Elizabeth; Dahanayake, Thinesh; Salibi, Rami; Honnons, Sylvie; Jones, Carolyn; Isern, Nancy G.; Hu, Jian Z.; Nathan, Steven D.; Grant, Geraldine; Phipps, Richard P.; Sime, Patricia J.

    2012-10-15

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex disease for which the pathogenesis is poorly understood. In this study, we identified lactic acid as a metabolite that is elevated in the lung tissue of patients with IPF. Objectives: This study examines the effect of lactic acid on myofibroblast differentiation and pulmonary fibrosis. Methods:We used metabolomic analysis to examine cellular metabolism in lung tissuefrom patients with IPFanddeterminedthe effects of lactic acid and lactate dehydrogenase-5 (LDH5) overexpression on myofibroblast differentiation and transforming growth factor (TGF)-b activation in vitro. Measurements and Main Results: Lactic acid concentrations from healthy and IPF lung tissue were determined by nuclear magnetic resonance spectroscopy; a-smooth muscle actin, calponin, and LDH5 expression were assessed by Western blot of cell culture lysates. Lactic acid and LDH5 were significantly elevated in IPF lung tissue compared with controls. Physiologic concentrations of lactic acid induced myofibroblast differentiation via activation of TGF-b. TGF-b induced expression of LDH5 via hypoxia-inducible factor 1a (HIF1a). Importantly, overexpression of both HIF1a and LDH5 in human lung fibroblasts induced myofibroblast differentiation and synergized with low dose TGF-b to induce differentiation. Furthermore, inhibition of both HIF1a and LDH5 inhibited TGF-b–induced myofibroblast differentiation. Conclusions: We have identified the metabolite lactic acid as an important mediator of myofibroblast differentiation via a pHdependent activation of TGF-b. We propose that the metabolic milieu of the lung, and potentially other tissues, is an important driving force behind myofibroblast differentiation and potentially the initiation and progression of fibrotic disorders.

  5. Lactic Acid Is Elevated in Idiopathic Pulmonary Fibrosis and Induces Myofibroblast Differentiation via pH-Dependent Activation of Transforming Growth Factor-?

    PubMed Central

    Kottmann, Robert Matthew; Kulkarni, Ajit A.; Smolnycki, Katie A.; Lyda, Elizabeth; Dahanayake, Thinesh; Salibi, Rami; Honnons, Sylvie; Jones, Carolyn; Isern, Nancy G.; Hu, Jian Z.; Nathan, Steven D.; Grant, Geraldine; Phipps, Richard P.

    2012-01-01

    Rationale: Idiopathic pulmonary fibrosis (IPF) is a complex disease for which the pathogenesis is poorly understood. In this study, we identified lactic acid as a metabolite that is elevated in the lung tissue of patients with IPF. Objectives: This study examines the effect of lactic acid on myofibroblast differentiation and pulmonary fibrosis. Methods: We used metabolomic analysis to examine cellular metabolism in lung tissue from patients with IPF and determined the effects of lactic acid and lactate dehydrogenase-5 (LDH5) overexpression on myofibroblast differentiation and transforming growth factor (TGF)-? activation in vitro. Measurements and Main Results: Lactic acid concentrations from healthy and IPF lung tissue were determined by nuclear magnetic resonance spectroscopy; ?-smooth muscle actin, calponin, and LDH5 expression were assessed by Western blot of cell culture lysates. Lactic acid and LDH5 were significantly elevated in IPF lung tissue compared with controls. Physiologic concentrations of lactic acid induced myofibroblast differentiation via activation of TGF-?. TGF-? induced expression of LDH5 via hypoxia-inducible factor 1? (HIF1?). Importantly, overexpression of both HIF1? and LDH5 in human lung fibroblasts induced myofibroblast differentiation and synergized with low-dose TGF-? to induce differentiation. Furthermore, inhibition of both HIF1? and LDH5 inhibited TGF-?induced myofibroblast differentiation. Conclusions: We have identified the metabolite lactic acid as an important mediator of myofibroblast differentiation via a pH-dependent activation of TGF-?. We propose that the metabolic milieu of the lung, and potentially other tissues, is an important driving force behind myofibroblast differentiation and potentially the initiation and progression of fibrotic disorders. PMID:22923663

  6. Exploring amino acid side chain decomposition using enzymatic digestion and HPLC-MS: combined lysine transformations in chlorinated waters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Characterizing the transformations of polypeptides is important across a broad range of scientific disciplines. As polypeptides are an important constituent of dissolved organic matter within seawater and freshwater, it is important to understand their fate. Oxidants formed in blood, as part of the ...

  7. Monitoring the Reaction Products of Perfluoropropionic Acid and Allyl Phenyl Ether Using Chirped-Pulse Fourier Transform Microwave Cp-Ftmw Spectroscopy

    NASA Astrophysics Data System (ADS)

    Frank, Derek S.; Obenchain, Daniel A.; Lin, Wei; Novick, Stewart E.; Cooke, S. A.; Grubbs, G. S., II

    2014-06-01

    The pure rotational spectra of the reaction mixture of perfluoropropionic acid, CF3CF2COOH, and allyl phenyl ether, C6H5OCH2CH=CH2, have been studied by a pulsed nozzle, chirped-pulse Fourier transform microwave spectrometer in the frequency range of 8-14 GHz. Transitions corresponding to multiple species, two of which being starting materials allyl phenyl ether and perfluoropropionic acid, have been observed and analyzed. Determination of the reaction products was carried out by matching observed rotational constants with ab initio quantum chemical calculations of predicted products and will be discussed. Rotational constants, centrifugal distortion constants and the assignment of allyl phenyl ether and reaction products spectra will all be discussed.

  8. Selective incorporation of ( sup 15 S)-hydroxyeicosatetraenoic acid in phosphatidylinositol of human neutrophils: Agonist-induced deacylation and transformation of stored hydroxyeicosanoids

    SciTech Connect

    Brezinski, M.E.; Serhan, C.N. )

    1990-08-01

    The uptake and mobilization of (15S)-hydroxy-5,8,11-cis-13-trans-eicosatetraenoic acid (15-HETE), a major product of arachidonic acid metabolism, was examined with human neutrophils. Upon exposure to labeled 15-HETE, PMNs rapidly (15 sec to 20 min) incorporated approximately 20% of the label into phosphatidylinositol, while less than 4% was associated with other phospholipid classes and neutral lipids. This pattern was distinct from that of either labeled arachidonate or labeled(5S)-hydroxy-8,11,14-cis-6-trans-eicosatetraenoic acid (5-HETE), which within 20 min were predominantly associated with triglycerides and phosphatidylcholine. After reversed-phase HPLC, greater than 98% of the label in phosphatidylinositol, isolated from PMNs, was released with phospholipase A2. Upon exposure to either chemotactic peptide (FMLP), phorbol 12-myristate 13-acetate, or an ionophore (A23187), 15-HETE-labeled PMNs released 15-HETE from phosphatidylinositol and displayed an impaired ability to generate leukotriene B4 (LTB4), 20-OH-LTB4, and 20-COOH-LTB4. Deacylated (3H)15-HETE was converted to (5S,15S)-dihydroxy-6,13-trans-8,11-cis-eicosatetraenoic acid (5,15-DHETE), lipoxin A4, and lipoxin B4, each carrying 3H label. PMNs labeled with 5-HETE also released and transformed this HETE when stimulated. However, the profile of labeled products differed between PMNs with either esterified 15-HETE or 5-HETE. When activated, 5-HETE-labeled PMNs generated both 5,20-DHETE and 5,15-DHETE but not labeled lipoxins. Threshold aggregation induced by FMLP with 15-HETE-labeled PMNs was inhibited, while the threshold response was relatively unimpaired with either A23187 or phorbol 12-myristate 13-acetate-induced aggregation. Results indicate that 15-HETE is esterified into phosphatidylinositol of PMNs, which can be mobilized and transformed upon exposure of the cells to a second signal.

  9. A Simple and Efficient Synthesis of an Acid-labile Polyphosphoramidate by Organobase-catalyzed Ring-Opening Polymerization and Transformation to Polyphosphoester Ionomers by Acid Treatment

    PubMed Central

    Zhang, Shiyi; Wang, Hai; Shen, Yuefei; Zhang, Fuwu; Seetho, Kellie; Zou, Jiong; Taylor, John-Stephen A.; Dove, Andrew P.; Wooley, Karen L.

    2013-01-01

    The direct synthesis of an acid-labile polyphosphoramidate by organobase-catalyzed ring-opening polymerization and an overall two-step preparation of polyphosphodiester ionomers (PPEI) by acid-assisted cleavage of the phosphoramidate bonds along the backbone of the polyphosphoramidate were developed in this study. The ultrafast organobase-catalyzed ring-opening polymerization of a cyclic phospholane methoxyethyl amidate monomer initiated by benzyl alcohol allowed for the preparation of well-defined polyphosphoramidates (PPA) with predictable molecular weights, narrow molecular weight distributions (PDI<1.10), and well-defined chain ends. Cleavage of the acid-labile phosphoramidate bonds on the polyphosphoramidate repeat units was evaluated under acidic conditions over a pH range of 1–5, and the complete hydrolysis produced polyphosphodiesters. The thermal properties of the resulting polyphosphoester ionomer acid and polyphosphoester ionomer sodium salt exhibited significant thermal stability. The parent PPA and both forms of the PPEIs showed low cytotoxicities toward HeLa cells and RAW 264.7 mouse macrophage cells. The synthetic methodology developed here has enriched the family of water-soluble polymers prepared by rapid and convenient organobase-catalyzed ring-opening polymerizations and straightforward chemical medication reactions, which are designed to be hydrolytically degradable and have promise for numerous biomedical and other applications. PMID:23997276

  10. A Simple and Efficient Synthesis of an Acid-labile Polyphosphoramidate by Organobase-catalyzed Ring-Opening Polymerization and Transformation to Polyphosphoester Ionomers by Acid Treatment.

    PubMed

    Zhang, Shiyi; Wang, Hai; Shen, Yuefei; Zhang, Fuwu; Seetho, Kellie; Zou, Jiong; Taylor, John-Stephen A; Dove, Andrew P; Wooley, Karen L

    2013-07-01

    The direct synthesis of an acid-labile polyphosphoramidate by organobase-catalyzed ring-opening polymerization and an overall two-step preparation of polyphosphodiester ionomers (PPEI) by acid-assisted cleavage of the phosphoramidate bonds along the backbone of the polyphosphoramidate were developed in this study. The ultrafast organobase-catalyzed ring-opening polymerization of a cyclic phospholane methoxyethyl amidate monomer initiated by benzyl alcohol allowed for the preparation of well-defined polyphosphoramidates (PPA) with predictable molecular weights, narrow molecular weight distributions (PDI<1.10), and well-defined chain ends. Cleavage of the acid-labile phosphoramidate bonds on the polyphosphoramidate repeat units was evaluated under acidic conditions over a pH range of 1-5, and the complete hydrolysis produced polyphosphodiesters. The thermal properties of the resulting polyphosphoester ionomer acid and polyphosphoester ionomer sodium salt exhibited significant thermal stability. The parent PPA and both forms of the PPEIs showed low cytotoxicities toward HeLa cells and RAW 264.7 mouse macrophage cells. The synthetic methodology developed here has enriched the family of water-soluble polymers prepared by rapid and convenient organobase-catalyzed ring-opening polymerizations and straightforward chemical medication reactions, which are designed to be hydrolytically degradable and have promise for numerous biomedical and other applications. PMID:23997276

  11. Reversible transformation between ?-oxo acids and ?-amino acids on ZnS particles: a photochemical model for tuning the prebiotic redox homoeostasis

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Liu, Xiaoyang; Yang, Yanqiang; Su, Wenhui

    2013-01-01

    How prebiotic metabolic pathways could have formed is an essential question for the origins of life on early Earth. From the abiogenetic point of view, the emergence of primordial metabolism may be postulated as a continuum from Earth's geochemical processes to chemoautotrophic biochemical procedures on mineral surfaces. In the present study, we examined in detail the reversible amination of ?-ketoglutarate on UV-irradiated ZnS particles under variable reaction conditions such as pH, temperature, hole scavenger species and concentrations, and different amino acids. It was observed that the reductive amination of ?-ketoglutarate and the oxidative amination of glutamate were both effectively performed on ZnS surfaces in the presence and absence of a hole scavenger, respectively. Accordingly, a photocatalytic mechanism was proposed. The reversible photochemical reaction was more efficient under basic conditions but independent of temperature in the range of 30-60 C. SO3 2- was more effective than S2- as the hole scavenger. Finally, we extended the glutamate dehydrogenase-like chemistry to a set of other ?-amino acids and their corresponding ?-oxo acids and found that hydrophobic amino acid side chains were more conducive to the reversible redox reactions. Since the experimental conditions are believed to have been prevalent in shallow water hydrothermal vent systems of early Earth, the results of this work not only suggest that the ZnS-assisted photochemical reaction can regulate the redox equilibrium between ?-amino acids and ?-oxo acids, but also provide a model of how prebiotic metabolic homoeostasis could have been developed and regulated. These findings can advance our understanding of the establishment of archaic non-enzymatic metabolic systems and the origins of autotrophy.

  12. Complete nucleotide and deduced amino acid sequences of human and murine preprocathepsin L. An abundant transcript induced by transformation of fibroblasts.

    PubMed

    Joseph, L J; Chang, L C; Stamenkovich, D; Sukhatme, V P

    1988-05-01

    Transfection of an activated rat oncogene into NIH3T3 fibroblasts leads to transformation and induction of a metastatic phenotype. To identify genes whose activation might mediate these processes, we used a differential screening strategy. A 1.5-kb transcript is induced fiftyfold, constitutes 1% of ras transformed cell messenger RNA (mRNA) and is the most abundantly induced message in these cells. Our sequence data shows that it encodes murine cathepsin L, a potent collagenolytic and elastinolytic lysosomal enzyme. The murine clone was used to isolate human cathepsin L complementary DNA (cDNA) clones. The complete nucleotide and deduced amino acid sequences of human and murine preprocathepsin L are presented and compared to other papain family cysteine proteinases. Northern analysis shows that both human and murine cathepsin L probes hybridize to a 1.5-kb transcript in several tissues, but also to a 4-kb transcript in human kidney. These clones will facilitate studies of the structure, expression, and function of cathepsin L, including its unexpected upregulation in transformation. PMID:2835398

  13. Multielement crystalline and pseudocrystalline oxides as efficient catalysts for the direct transformation of glycerol into acrylic acid.

    PubMed

    Chieregato, Alessandro; Soriano, M Dolores; Garca-Gonzlez, Ester; Puglia, Giuseppe; Basile, Francesco; Concepcin, Patricia; Bandinelli, Claudia; Lpez Nieto, Jos M; Cavani, Fabrizio

    2015-01-01

    Glycerol surplus from biodiesel synthesis still represents a major problem in the biofuel production chain. Meanwhile, those in the acrylic acid market are looking for new processes that are able to offer viable alternatives to propylene-based production. Therefore, acrylic acid synthesis from glycerol could be an effective solution to both issues. Among the viable routes, one-pot synthesis theoretically represents the most efficient process, but it is also highly challenging from the catalyst design standpoint. A new class of complex W--Mo--V mixed-oxide catalysts, which are strongly related to the hexagonal tungsten bronze structure, able to directly convert glycerol into acrylic acid with yields of up to 51?% are reported. PMID:25488515

  14. Palladium(II)-Catalyzed Synthesis of Sulfinates from Boronic Acids and DABSO: A Redox-Neutral, Phosphine-Free Transformation.

    PubMed

    Deeming, Alex S; Russell, Claire J; Willis, Michael C

    2016-01-11

    A redox-neutral palladium(II)-catalyzed conversion of aryl, heteroaryl, and alkenyl boronic acids into sulfinate intermediates, and onwards to sulfones and sulfonamides, has been realized. A simple Pd(OAc)2 catalyst, in combination with the sulfur dioxide surrogate 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) (DABSO), is sufficient to achieve rapid and high-yielding conversion of the boronic acids into the corresponding sulfinates. Addition of C- or N-based electrophiles then allows conversion into sulfones and sulfonamides, respectively, in a one-pot, two-step process. PMID:26596861

  15. The mixed valent tellurate SrTe{sub 3}O{sub 8}: Electronic lone pair effect of Te{sup 4+}

    SciTech Connect

    Barrier, N. . E-mail: nicolas.barrier@ensicaen.fr; Malo, S.; Hernandez, O.; Hervieu, M.; Raveau, B.

    2006-11-15

    A novel mixed valent tellurium oxide, SrTe{sub 3}O{sub 8}, has been synthesized and its crystal structure was determined ab initio from powder X-ray diffraction data. This oxide, which crystallizes in a tetragonal unit-cell, P4{sub 2}/m space group, with very close a and c cell parameters (6.8257(1) and 6.7603(1) A, respectively), exhibits a very original structure built up of corner-sharing TeO{sub 6} (Te{sup 6+}) octahedra and Te{sub 2}O{sub 8} (Te{sup 4+}) twin-pyramidal units. The latter ones form [Te{sub 3}O{sub 8}]{sub {infinity}} chains running along the [001] and the [110] directions. Besides the four sided tunnels where the Sr{sup 2+} cations are located, there are very large four sided tunnels running along the c-axis which are obstructed by the electronic lone pairs of the Te{sup 4+} cations. -- Graphical abstract: Tunnel structure of the mixed valent tellurate SrTe{sub 3}O{sub 8} determined ab initio against powder X-ray diffraction; structure viewed along [001] direction with E the electronic lone pairs of the Te{sup 4+} cations.

  16. CHEMISTRY OF FOG WATER IN CALIFORNIA'S CENTRAL VALLEY: 2. PHOTOCHEMICAL TRANSFORMATIONS OF AMINO ACIDS AND ALKYL AMINES. (R825433)

    EPA Science Inventory

    Although amino compounds are seemingly ubiquitous in atmospheric particles and deposition, little is known of their fate in the troposphere. We report here on the fate of 21 amino acids and alkyl amines in fog waters from Davis, California, illuminated with simulated sunlight ...

  17. Radiation-induced transformations of matrix-isolated formic acid: evidence for the HCOOH ? HOCO + H channel.

    PubMed

    Ryazantsev, Sergey V; Feldman, Vladimir I

    2015-11-11

    The effect of X-ray irradiation on the isolated formic acid molecules (HCOOH) in solid noble gas matrices (Xe, Kr, Ar, and Ne) at very low temperatures (6 K) was first studied by FTIR spectroscopy. Carbon oxides (CO and CO2) and hydrocarboxyl radicals (HOCO) have been detected as the principal degradation products. The formation of HOCO radicals represents a primary dissociation channel for formic acid, which was not reported previously under UV photolysis in solids. This reaction can be explained by the involvement of the recombination-induced excited states, which are not populated in photolysis. The effects of the matrix and the absorbed dose on the product formation were studied in detail and possible mechanisms are discussed with particular attention to the difference between radiolysis and UV-photolysis of the matrix-isolated formic acid. The results obtained provide a new insight into the effects of high-energy impact on the simplest carboxylic acid with possible implications to the astrochemical problems, in particular, the prebiotic evolution in the interstellar medium. PMID:26524429

  18. A Fourier transform infrared spectroscopic study of Mg-rich, Mg-poor and acid leached palygorskites.

    PubMed

    Cai, Yuanfeng; Xue, Jiyue; Polya, D A

    2007-02-01

    The FTIR spectra of pure magnesium-rich (Mg-rich) and magnesium-poor (Mg-poor) palygorskites, before and after short-term (<7 h) and long-term (360 h) acid leaching are presented here. Comparison of decomposition spectra of Mg-rich and Mg-poor palygorskites clearly shows that the absorption peaks related to pairs of octahedral cation differ depending on the octahedral site occupancy. Short-term acid leaching of palygorskites results in significant changes to FTIR absorption bands near 1200 and 790 cm-1. As the acid attack progresses, the band at 1200 cm-1 shifts to lower wavenumbers, whilst the band at 790 cm-1, which here is assigned to SiU-O-SiD symmetrical stretching vibration, shifts to higher wavelengths. Longer-term leaching of palygorskites results in the disappearance of 900-1200 cm-1 absorption bands, showing that the palygorskite has largely decomposed to amorphous silica. Assignments of several other bands have been made as follows: several vibrations relate to OH, i.e. 847 cm-1, hygroscopic water (1635 cm-1), Si-O vibrations 1100, 611-621, 470-481 cm-1, etc. appear in the FTIR spectra of 360 h acid leached palygorskite. Three bands near 1100, 611-621 and 470-481 cm-1 relate to Si-O vibration of an ideal hexagonal (Si2O5)n sheet. PMID:16824788

  19. Transformation of cinnamic acid from trans- to cis-form raises a notable bactericidal and synergistic activity against multiple-drug resistant Mycobacterium tuberculosis.

    PubMed

    Chen, Yen-Ling; Huang, Shao-Tsung; Sun, Fang-Ming; Chiang, Yu-Ling; Chiang, Chia-Jung; Tsai, Chiung-Man; Weng, Chia-Jui

    2011-06-14

    Tuberculosis (TB) is a contagious disease caused by Mycobacterium tuberculosis. The long course of treatments on TB with a combination of antibiotics leads unfavorable side effects and poor patient compliance which contributes to sustaining multiple-drug resistant tuberculosis (MDR-TB). Therefore, the development of a new effective drug or synergist to reduce the prevalence of MDR-TB is urgent to date. Cinnamic acid (CA) is a natural occurring phenolic compound with anti-microbial activity. Both trans- and cis-isoforms of CA exist in planta, and cis-cinnamic acid (c-CA) can be transformed from trans-cinnamic acid (t-CA) under sunlight. Due to the unavailability of c-CA, the literature regarding the biological functions of c-CA is still limited. We had previously developed a practicable method for the transformation of c-CA from t-CA and the isolation of c-CA. Using the techniques, sufficient c-CA was obtained to evaluate its antituberculosis activity against a MDR M. tuberculosis strain. Moreover, the synergistic effects of c-CA and t-CA with two first-line anti-TB antibiotics, isoniazid (INH) and rifampicin (RIF), were also determined. Although both of c-CA and t-CA decreased the viability of MDR-TB bacilli in a dose-dependent manner, the antituberculosis activity of c-CA was approximately 120-fold of t-CA. Furthermore, the c-CA exhibited higher synergistic effect with INH or RIF against tuberculosis than t-CA. The micrographs of scanning electron microscope (SEM) display that c-CA caused an injury on the out-layer of MDR-TB bacilli. The c-CA might be a potential anti-mycobacterial or synergistic agent that can be developed to against tuberculosis. PMID:21536127

  20. Determination and occurrence of phenoxyacetic acid herbicides and their transformation products in groundwater using ultra high performance liquid chromatography coupled to tandem mass spectrometry.

    PubMed

    McManus, Sarah-Louise; Moloney, Mary; Richards, Karl G; Coxon, Catherine E; Danaher, Martin

    2014-01-01

    A sensitive method was developed and validated for ten phenoxyacetic acid herbicides, six of their main transformation products (TPs) and two benzonitrile TPs in groundwater. The parent compounds mecoprop, mecoprop-p, 2,4-D, dicamba, MCPA, triclopyr, fluroxypr, bromoxynil, bentazone, and 2,3,6-trichlorobenzoic acid (TBA) are included and a selection of their main TPs: phenoxyacetic acid (PAC), 2,4,5-trichloro-phenol (TCP), 4-chloro-2-methylphenol (4C2MP), 2,4-dichlorophenol (DCP), 3,5,6-trichloro-2-pyridinol (T2P), and 3,5-dibromo-4-hydroxybenzoic acid (BrAC), as well as the dichlobenil TPs 2,6-dichlorobenzamide (BAM) and 3,5-dichlorobenzoic acid (DBA) which have never before been determined in Irish groundwater. Water samples were analysed using an efficient ultra-high performance liquid chromatography (UHPLC) method in an 11.9 min separation time prior to detection by tandem mass spectrometry (MS/MS). The limit of detection (LOD) of the method ranged between 0.00008 and 0.0047 µg·L(-1) for the 18 analytes. All compounds could be detected below the permitted limits of 0.1 µg·L(-1) allowed in the European Union (EU) drinking water legislation. The method was validated according to EU protocols laid out in SANCO/10232/2006 with recoveries ranging between 71% and 118% at the spiked concentration level of 0.06 µg·L(-1). The method was successfully applied to 42 groundwater samples collected across several locations in Ireland in March 2012 to reveal that the TPs PAC and 4C2MP were detected just as often as their parent active ingredients (a.i.) in groundwater. PMID:25514054

  1. In situ determination of transient pKa changes of internal amino acids of bacteriorhodopsin by using time-resolved attenuated total reflection Fourier-transform infrared spectroscopy

    PubMed Central

    Zscherp, Christian; Schlesinger, Ramona; Tittor, Jrg; Oesterhelt, Dieter; Heberle, Joachim

    1999-01-01

    Active proton transfer through membrane proteins is accomplished by shifts in the acidity of internal amino acids, prosthetic groups, and water molecules. The recently introduced step-scan attenuated total reflection Fourier-transform infrared (ATR/FT-IR) spectroscopy was employed to determine transient pKa changes of single amino acid side chains of the proton pump bacteriorhodopsin. The high pKa of D96 (>12 in the ground state) drops to 7.1 0.2 (in 1 M KCl) during the lifetime of the N intermediate, quantitating the role of D96 as the internal proton donor of the retinal Schiff base. We conclude from experiments on the pH dependence of the proton release reaction and on point mutants where each of the glutamates on the extracellular surface has been exchanged that besides D85 no other carboxylic group changes its protonation state during proton release. However, E194 and E204 interact with D85, the primary proton acceptor of the Schiff base proton. The C?O stretching vibration of D85 undergoes a characteristic pH-dependent shift in frequency during the M state of wild-type bacteriorhodopsin with a pKa of 5.2 (0.3) which is abolished in the single-site mutants E194Q and E204Q and the quadruple mutant E9Q/E74Q/E194Q/E204Q. The double mutation E9Q/E74Q does not affect the lifetime of the intermediates, ruling out any participation of these residues in the proton transfer chain of bacteriorhodopsin. This study demonstrates that transient changes in acidity of single amino acid residues can be quantified in situ with infrared spectroscopy. PMID:10318912

  2. Characterization of the Adsorption of Nucleic Acid Bases onto Ferrihydrite via Fourier Transform Infrared and Surface-Enhanced Raman Spectroscopy and X-ray Diffractometry.

    PubMed

    Canhisares-Filho, Jos E; Carneiro, Cristine E A; de Santana, Henrique; Urbano, Alexandre; da Costa, Antonio C S; Zaia, Cssia T B V; Zaia, Dimas A M

    2015-09-01

    Minerals could have played an important role in concentration, protection, and polymerization of biomolecules. Although iron is the fourth most abundant element in Earth's crust, there are few works in the literature that describe the use of iron oxide-hydroxide in prebiotic chemistry experiments. In the present work, the interaction of adenine, thymine, and uracil with ferrihydrite was studied under conditions that resemble those of prebiotic Earth. At acidic pH, anions in artificial seawater decreased the pH at the point of zero charge (pHpzc) of ferrihydrite; and at basic pH, cations increased the pHpzc. The adsorption of nucleic acid bases onto ferrihydrite followed the order adenine?> uracil?>?thymine. Adenine adsorption peaked at neutral pH; however, for thymine and uracil, adsorption increased with increasing pH. Electrostatic interactions did not appear to play an important role on the adsorption of nucleic acid bases onto ferrihydrite. Adenine adsorption onto ferrihydrite was higher in distilled water compared to artificial seawater. After ferrihydrite was mixed with artificial seawaters or nucleic acid bases, X-ray diffractograms and Fourier transform infrared spectra did not show any change. Surface-enhanced Raman spectroscopy showed that the interaction of adenine with ferrihydrite was not pH-dependent. In contrast, the interactions of thymine and uracil with ferrihydrite were pH-dependent such that, at basic pH, thymine and uracil lay flat on the surface of ferrihydrite, and at acidic pH, thymine and uracil were perpendicular to the surface. Ferrihydrite adsorbed much more adenine than thymine; thus adenine would have been better protected against degradation by hydrolysis or UV radiation on prebiotic Earth. PMID:26393397

  3. Fourier Transform Infrared Spectroscopy and Multivariate Analysis for Online Monitoring of Dibutyl Phosphate Degradation Product in Tributyl Phosphate/n-Dodecane/Nitric Acid Solvent

    SciTech Connect

    Tatiana G. Levitskaia; James M. Peterson; Emily L. Campbell; Amanda J. Casella; Dean R. Peterman; Samuel A. Bryan

    2013-12-01

    In liquid–liquid extraction separation processes, accumulation of organic solvent degradation products is detrimental to the process robustness, and frequent solvent analysis is warranted. Our research explores the feasibility of online monitoring of the organic solvents relevant to used nuclear fuel reprocessing. This paper describes the first phase of developing a system for monitoring the tributyl phosphate (TBP)/n-dodecane solvent commonly used to separate used nuclear fuel. In this investigation, the effect of extraction of nitric acid from aqueous solutions of variable concentrations on the quantification of TBP and its major degradation product dibutylphosphoric acid (HDBP) was assessed. Fourier transform infrared (FTIR) spectroscopy was used to discriminate between HDBP and TBP in the nitric acid-containing TBP/n-dodecane solvent. Multivariate analysis of the spectral data facilitated the development of regression models for HDBP and TBP quantification in real time, enabling online implementation of the monitoring system. The predictive regression models were validated using TBP/n-dodecane solvent samples subjected to high-dose external ?-irradiation. The predictive models were translated to flow conditions using a hollow fiber FTIR probe installed in a centrifugal contactor extraction apparatus, demonstrating the applicability of the FTIR technique coupled with multivariate analysis for the online monitoring of the organic solvent degradation products.

  4. Fourier Transform Infrared Spectroscopy and Multivariate Analysis for Online Monitoring of Dibutyl Phosphate Degradation Product in Tributyl Phosphate /n-Dodecane/Nitric Acid Solvent

    SciTech Connect

    Levitskaia, Tatiana G.; Peterson, James M.; Campbell, Emily L.; Casella, Amanda J.; Peterman, Dean; Bryan, Samuel A.

    2013-11-05

    In liquid-liquid extraction separation processes, accumulation of organic solvent degradation products is detrimental to the process robustness and frequent solvent analysis is warranted. Our research explores feasibility of online monitoring of the organic solvents relevant to used nuclear fuel reprocessing. This paper describes the first phase of developing a system for monitoring the tributyl phosphate (TBP)/n-dodecane solvent commonly used to separate used nuclear fuel. In this investigation, the effect of extraction of nitric acid from aqueous solutions of variable concentrations on the quantification of TBP and its major degradation product dibutyl phosphoric acid (HDBP) was assessed. Fourier Transform Infrared Spectroscopy (FTIR) spectroscopy was used to discriminate between HDBP and TBP in the nitric acid-containing TBP/n-dodecane solvent. Multivariate analysis of the spectral data facilitated the development of regression models for HDBP and TBP quantification in real time, enabling online implementation of the monitoring system. The predictive regression models were validated using TBP/n-dodecane solvent samples subjected to the high dose external gamma irradiation. The predictive models were translated to flow conditions using a hollow fiber FTIR probe installed in a centrifugal contactor extraction apparatus demonstrating the applicability of the FTIR technique coupled with multivariate analysis for the online monitoring of the organic solvent degradation products.

  5. Identification of black carbon derived structures in a volcanic ash soil humic acid by Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Kramer, Robert W; Kujawinski, Elizabeth B; Hatcher, Patrick G

    2004-06-15

    Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), coupled with cross-polarization magic angle spinning 13C nuclear magnetic resonance (NMR) spectroscopy and Kendrick mass defect analysis, was used to study the molecular composition of an aromatic carbon-rich humic acid extracted from a dark black soil from Iwata, Japan. Black carbon, produced by the incomplete combustion of fossil fuels and organic matter, has been suggested as a major component of humic acids having intense peaks in the aromatic and carboxyl regions of the 13C NMR spectrum. Taking advantage of the high resolving power of FT-ICR MS to make precise formula assignments, three different types of highly carboxylated polycyclic aromatic compounds were identified in the sample: linearly fused aromatic structures, aromatic structures linked by carbon-carbon single bonds, and highly condensed aromatic structures. These carboxylated aromatic structures have a low mass defect in their mass spectra due to their abundance of oxygen and deficiency of hydrogen. This mass defect is observed in the vast majority of peaks present in the entire mass spectrum, differentiating them from structures that are hydrogen-rich (e.g., fatty acids, proteins, carbohydrates). Thus, we conclude that the bulk of the sample analyzed is comprised of these heavily carboxylated, hydrogen-deficient, condensed aromatic structures, features believed to be characteristic of black carbon-like material. PMID:15260339

  6. Electrochemistry for biofuel generation: transformation of fatty acids and triglycerides to diesel-like olefin/ether mixtures and olefins.

    PubMed

    dos Santos, Tatiane R; Harnisch, Falk; Nilges, Peter; Schrder, Uwe

    2015-03-01

    Electroorganic synthesis can be exploited for the production of biofuels from fatty acids and triglycerides. With Coulomb efficiencies (CE) of up to 50?%, the electrochemical decarboxylation of fatty acids in methanolic and ethanolic solutions leads to the formation of diesel-like olefin/ether mixtures. Triglycerides can be directly converted in aqueous solutions by using sonoelectrochemistry, with olefins as the main products (with a CE of more than 20?%). The latter reaction, however, is terminated at around 50?% substrate conversion by the produced side-product glycerol. An energy analysis shows that the electrochemical olefin synthesis can be an energetically competitive, sustainable, and--in comparison with established processes--economically feasible alternative for the exploitation of fats and oils for biofuel production. PMID:25648972

  7. Submolecular regulation of cell transformation by deuterium depleting water exchange reactions in the tricarboxylic acid substrate cycle.

    PubMed

    Boros, Lszl G; D'Agostino, Dominic P; Katz, Howard E; Roth, Justine P; Meuillet, Emmanuelle J; Somlyai, Gbor

    2016-02-01

    The naturally occurring isotope of hydrogen ((1)H), deuterium ((2)H), could have an important biological role. Deuterium depleted water delays tumor progression in mice, dogs, cats and humans. Hydratase enzymes of the tricarboxylic acid (TCA) cycle control cell growth and deplete deuterium from redox cofactors, fatty acids and DNA, which undergo hydride ion and hydrogen atom transfer reactions. A model is proposed that emphasizes the terminal complex of mitochondrial electron transport chain reducing molecular oxygen to deuterium depleted water (DDW); this affects gluconeogenesis as well as fatty acid oxidation. In the former, the DDW is thought to diminish the deuteration of sugar-phosphates in the DNA backbone, helping to preserve stability of hydrogen bond networks, possibly protecting against aneuploidy and resisting strand breaks, occurring upon exposure to radiation and certain anticancer chemotherapeutics. DDW is proposed here to link cancer prevention and treatment using natural ketogenic diets, low deuterium drinking water, as well as DDW production as the mitochondrial downstream mechanism of targeted anti-cancer drugs such as Avastin and Glivec. The role of (2)H in biology is a potential missing link to the elusive cancer puzzle seemingly correlated with cancer epidemiology in western populations as a result of excessive (2)H loading from processed carbohydrate intake in place of natural fat consumption. PMID:26826644

  8. Interleukin-8 (IL-8) over-production and autocrine cell activation are key factors in monomethylarsonous acid [MMA(III)]-induced malignant transformation of urothelial cells

    SciTech Connect

    Escudero-Lourdes, C.; Wu, T.; Camarillo, J.M.; Gandolfi, A.J.

    2012-01-01

    The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50 nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized model of urothelial cells (UROtsa), with only 3 mo of exposure necessary to trigger the transformation-related changes. In the three-month window of exposure, the cells over-expressed pro-inflammatory cytokines (IL-1?, IL-6 and IL-8), consistent with the sustained activation of NFK? and AP1/c-jun, ERK2, and STAT3. IL-8 was over-expressed within hours after exposure to MMA(III), and sustained over-expression was observed during chronic exposure. In this study, we profiled IL-8 expression in UROtsa cells exposed to 50 nM MMA(III) for 1 to 5 mo. IL-8 expression was increased mainly in cells after 3 mo MMA(III) exposure, and its production was also found increased in tumors derived from these cells after heterotransplantation in SCID mice. UROtsa cells do express both receptors, CXCR1 and CXCR2, suggesting that autocrine cell activation could be important in cell transformation. Supporting this observation and consistent with IL-8 over-expression, CXCR1 internalization was significantly increased after three months of exposure to MMA(III). The expression of MMP-9, cyclin D1, bcl-2, and VGEF was significantly increased in cells exposed to MMA(III) for 3 mo, but these mitogen-activated kinases were significantly decreased after IL-8 gene silencing, together with a decrease in cell proliferation rate and in anchorage-independent colony formation. These results suggest a relevant role of IL-8 in MMA(III)-induced UROtsa cell transformation. -- Highlights: ? IL-8 is over-expressed in human MMA(III)-exposed urothelial cells. ? Internal CXCR1 and tumor progression markers are also increased. ? IL-8 silencing decreased malignant transformation markers in MMA(III)-exposed cells.

  9. Transforming growth factor-beta 1 stimulates vascular smooth muscle cell L-proline transport by inducing system A amino acid transporter 2 (SAT2) gene expression.

    PubMed Central

    Ensenat, D; Hassan, S; Reyna, S V; Schafer, A I; Durante, W

    2001-01-01

    Transforming growth factor-beta1 (TGF-beta 1) is a multifunctional cytokine that contributes to arterial remodelling by stimulating vascular smooth muscle cell (SMC) growth and collagen synthesis at sites of vascular injury. Since l-proline is essential for the synthesis of collagen, we examined whether TGF-beta 1 regulates the transcellular transport of l-proline by vascular SMCs. l-Proline uptake by vascular SMCs was primarily sodium-dependent, pH-sensitive, blocked by neutral amino acids and alpha-(methylamino)isobutyric acid, and exhibited trans-inhibition. Treatment of SMCs with TGF-beta 1 stimulated l-proline transport in a concentration- and time-dependent manner. The TGF-beta 1-mediated l-proline uptake was inhibited by cycloheximide or actinomycin D. Kinetic studies indicated that TGF-beta 1-induced l-proline transport was mediated by an increase in transport capacity independent of any changes in the affinity for l-proline. TGF-beta 1 stimulated the expression of system A amino acid transporter 2 (SAT2) mRNA in a time-dependent fashion that paralleled the increase in l-proline transport. Reverse transcriptase PCR failed to detect the presence of SAT1 or amino acid transporter 3 (ATA3) in either untreated or TGF-beta 1-treated SMCs. These results demonstrate that l-proline transport by vascular SMCs is mediated predominantly by the SAT and that TGF-beta 1 stimulates SMC l-proline uptake by inducing the expression of the SAT2 gene. The ability of TGF-beta 1 to induce SAT2 expression may function to provide SMCs with the necessary levels of l-proline required for collagen synthesis and cell growth. PMID:11716780

  10. Nondestructive quantification of the soluble-solids content and the available acidity of apples by Fourier-transform near-infrared spectroscopy

    SciTech Connect

    Ying Yibin; Liu Yande; Tao Yang

    2005-09-01

    This research evaluated the feasibility of using Fourier-transform near-infrared (FT-NIR) spectroscopy to quantify the soluble-solids content (SSC) and the available acidity (VA) in intact apples. Partial least-squares calibration models, obtained from several preprocessing techniques (smoothing, derivative, etc.) in several wave-number ranges were compared. The best models were obtained with the high coefficient determination (r{sup 2}) 0.940 for the SSC and a moderate r{sup 2} of 0.801 for the VA, root-mean-square errors of prediction of 0.272% and 0.053%, and root-mean-square errors of calibration of 0.261% and 0.046%, respectively. The results indicate that the FT-NIR spectroscopy yields good predictions of the SSC and also showed the feasibility of using it to predict the VA of apples.

  11. Hyperfine structure in the rotational spectra of trans-formic acid: Lamb-dip measurements and quantum-chemical calculations

    NASA Astrophysics Data System (ADS)

    Cazzoli, G.; Puzzarini, C.; Stopkowicz, S.; Gauss, J.

    2010-09-01

    Context. Formic acid, HCOOH, is the simplest organic acid and the first that has been identified in the interstellar medium. Its astrophysical relevance has motivated this spectroscopic study. Aims: The aim of this investigation is to provide very accurate rest frequencies for the trans isomer of HCOOH as well as to improve the spectroscopic and hyperfine parameters available in the literature for this molecule. Methods: The Lamb-dip technique has been exploited in order to record the rotational spectrum of trans-HCOOH at sub-Doppler resolution in the millimeter- and submillimeter-wave frequency ranges and, when possible, to resolve the hyperfine structure due to the hydrogen nuclei. THz measurements have been carried out as well. The experimental investigation has been supported by high-level quantum-chemical calculations. Results: As a consequence, we report here the most accurate ground-state rotational parameters known so far for the main isotopic species of trans-HCOOH as well as an accurate and reliable set of hyperfine parameters. Conclusions: The improvement in the accuracy of the ground-state rotational and hyperfine parameters as well as of the rest frequencies of rotational transitions might therefore be useful for future radioastronomical observations. Tables S1 and S2 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/520/A64

  12. Subcellular damage kinetics within co-cultivated WI38 and VA13-transformed WI38 human fibroblasts following 5-aminolevulinic acid-induced protoporphyrin IX formation.

    PubMed

    Uberriegler, K P; Banieghbal, E; Krammer, B

    1995-12-01

    The generation of the photosensitizer protoporphyrin IX (PpIX) in cells can be induced by externally applied 5-aminolevulinic acid (ALA), with that bypassing the feedback control mechanism. The aim of the present study was to investigate the onset of destructive changes in living cocultivated WI38 and VA13-transformed WI38 human fibroblasts following ALA incubation, PpIX production and subsequent irradiation by white halogen light with a dose of 2.2 kJ/m2. Specific fluorescence markers such as 3,3'-dihexyloxacarbocyanine iodide for endoplasmic reticulum (ER) staining and dihydrorhodamine for intact mitochondria mapping combined with a low light imaging system are a versatile and sensitive tool to examine the photoinduced destruction of organelles in living cells, while artifacts are minimized. Mitochondria as primary targets of PpIX undergo a condensation under irradiation and are finally destroyed. Photodynamic treatment induces further a significant decomposition of ER, although PpIX localization could not be determined. Initial destabilization and vesiculation of ER is followed by a porous network with large cisternae (indicating the breakdown of cell integrity and cell/nucleus membrane damage). Normal cocultivated lung fibroblasts showed a delay in destruction compared to the transformed WI38-VA13 cells. The observed decomposition pattern resembles the morphological pattern of apoptosis. PMID:8570739

  13. The immunomodulator, ammonium trichloro[1,2-ethanediolato-O,O']-tellurate, suppresses the propagation of herpes simplex virus 2 by reducing the infectivity of the virus progeny.

    PubMed

    Sheinboim, D; Hindiyeh, M; Mendelson, E; Albeck, M; Sredni, B; Dovrat, S

    2015-07-01

    Persistent investigations for the identification of novel anti-herpetic drugs are being conducted worldwide, as current treatment options are sometimes insufficient. The immunomodulator, ammonium trichloro[1,2‑ethanediolato‑O,O']‑tellurate (AS101), a non‑toxic tellurium (Ⅳ) compound, has been shown to exhibit anti‑viral activity against a variety of viruses in cell cultures and in animal models. In the present study, the anti‑viral activity of AS101 against herpes simplex virus (HSV)‑1 and 2 was investigated in vitro. The results demonstrated that AS101 significantly restricted HSV‑2-induced plaque formation and reduced the infectivity of the HSV‑2 yield, while HSV‑1 was affected to a lesser extent. The incubation of mature HSV‑1 and HSV‑2 viruses with AS101 had no effect on viral infectivity, indicating that the compound interrupts de novo viral synthesis. The addition of AS101 at up to 9 h post‑infection had almost the same effect as did the addition of the drug together with the virus (it maintained 80% of its total anti‑viral capacity). Quantitative PCR and immunofluoresence staining of viral structural proteins revealed that the viral DNA and protein synthesis stages were not interrupted by the administration of AS101. By contrast, in the presence of the compound, significantly fewer viable viruses (≥2 log reduction) were recovered from the AS10‑treated cell cultures. Of note, when we determined the viability of the intracellular virus, formed in the presence of the compound, a less severe (≤1 log) effect was observed. Taken together, these data strongly suggest that AS101 primarily interferes with late stages of viral replication, such as viral particle envelopment or egress, leading to the production of a defective virus progeny. PMID:25936393

  14. Transformation of 2,4,6-trimethylphenol and furfuryl alcohol, photosensitised by Aldrich humic acids subject to different filtration procedures.

    PubMed

    Minella, Marco; Merlo, Maria Paola; Maurino, Valter; Minero, Claudio; Vione, Davide

    2013-01-01

    Suspended particles in a system made up of Aldrich humic acids (HAs) in water account for about 13% of the total HA mass, 10-11% of the organic carbon and 9-11% of radiation extinction in the UVA region. Extinction would be made up of radiation scattering (less than one third) and absorption (over two thirds). The contribution of particles to the degradation rates of trimethylphenol and furfuryl alcohol (FFA) (probes of triplet states and (1)O(2), respectively) was lower than 10% and possibly negligible. The results indicate that triplet states and (1)O(2) occurring in the solution bulk are mostly produced by the dissolved HA fraction. Experimental data would not exclude production of (1)O(2) in particle hydrophobic cores, unavailable for reaction with FFA. However, the limited to negligible particle fluorescence places an upper limit to particle core photoactivity. PMID:22921648

  15. Accumulation, transformation and tissue distribution of domoic acid, the amnesic shellfish poisoning toxin, in the common cuttlefish, Sepia officinalis.

    PubMed

    Costa, Pedro R; Rosa, Rui; Duarte-Silva, Alexandra; Brotas, Vanda; Sampayo, Maria Antnia M

    2005-08-15

    Domoic acid (DA) is a phycotoxin produced by some diatoms, mainly from the Pseudo-nitzschia genus, and has been detected throughout the marine food web. Although DA has been frequently found in cephalopod prey such as crustaceans and fish, little is known about DA accumulation in these molluscs. This study presents the first data showing relevant concentrations of DA detected in the common cuttlefish, Sepia officinalis, which is one of the most studied cephalopod species in the world. Domoic acid was consistently found throughout 2003 and 2004 in the digestive gland of cuttlefish reaching concentrations of 241.7 microg DA g(-1). The highest DA values were detected during spring and summer months, periods when Pseudo-nitzschia occur in the plankton. In fact, Pseudo-nitzschia blooms preceded the highest DA concentrations in cuttlefish. Evaluation of DA tissue distribution showed elevated DA concentrations in the digestive gland and branchial hearts. Further, DA isomers comprised a relevant percentage of the toxin profile, indicating degradation and biotransformation of the toxin in the branchial hearts. The common cuttlefish, like other cephalopod species, plays a central position in the food web and might be a new DA vector to top predators like marine mammals. Human intoxications are not expected since DA was only seldom detected in the mantle and even then in very low levels (max 0.7 microg DA g(-1)). However, in some countries whole juvenile animals are consumed (i.e. without evisceration) and in this case they might represent a risk to human health. This study contributes to understanding the occurrence of phycotoxins in cephalopods and reveals a new member of the marine food web able to accumulate DA. PMID:15961171

  16. Tracking the composition and transformation of humic and fulvic acids during vermicomposting of sewage sludge by elemental analysis and fluorescence excitation-emission matrix.

    PubMed

    Zhang, Jie; Lv, Baoyi; Xing, Meiyan; Yang, Jian

    2015-05-01

    Sewage sludge (T1) and the mixture of sewage sludge and cattle dung (T2) were vermicomposted with Eisenia fetida, respectively. The transformation of humic acid (HA) and fulvic acid (FA) extracted from these two treatments were evaluated by a series of chemical and spectroscopic methods. Results indicated that the vermicomposting decreased pH, TOC, and C/N ratio, and increased EC, total extractable C, and HA contents. The FA content in treatment T1 was increased significantly, and only slight increasing was observed in treatment T2. Moreover, vermicomposting decreased H content, C/N ratio, proteinaceous and carbohydrates components, and increased the N content, C/H ratio, aromatic compounds and polycondensation structures in HA and FA. In addition, fluorescence spectra and fluorescence regional integration indicated that protein-like groups were degraded and HA compounds were formed. Furthermore, the addition of cattle dung enhanced the humification process and improved the HA quality in spite of no significant effect on the FA. PMID:25736580

  17. Strong Lewis acids of air-stable metallocene bis(perfluorooctanesulfonate)s as high-efficiency catalysts for carbonyl-group transformation reactions.

    PubMed

    Qiu, Renhua; Xu, Xinhua; Peng, Lifeng; Zhao, Yalei; Li, Ningbo; Yin, Shuangfeng

    2012-05-14

    Strong Lewis acids of air-stable metallocene bis(perfluorooctanesulfonate)s [M(Cp)(2)][OSO(2)C(8)F(17)](2)?nH(2)O?THF (M = Zr (2?a?3?H(2)O?THF), M = Ti (2?b?2?H(2)O?THF)) were synthesized by the reaction of [M(Cp)(2)]Cl(2) (M = Zr (1?a), M = Ti (1?b)) with nBuLi and C(8)F(17)SO(3)H (2?equiv) or with C(8)F(17)SO(3)Ag (2?equiv). The hydrate numbers (n) of these complexes were variable, changing from 0 to 4 depending on conditions. In contrast to well-known metallocene triflates, these complexes suffered no change in open air for a year. thermogravimetry-differential scanning calorimetry (TG-DSC) analysis showed that 2?a and 2?b were thermally stable at 300 and 180?C, respectively. These complexes exhibited unusually high solubility in polar organic solvents. Conductivity measurement showed that the complexes (2?a and 2?b) were ionic dissociation in CH(3)CN solution. X-ray analysis result confirmed 2?a?3?H(2)O?THF was a cationic organometallic Lewis acid. UV/Vis spectra showed a significant red shift due to the strong complex formation between 10-methylacridone and 2?a. Fluorescence spectra showed that the Lewis acidity of 2?a fell between those of Sc(3+) (?(em)=474?nm) and Fe(3+) (?(em)=478?nm). ESR spectra showed the Lewis acidity of 2?a (0.91?eV) was at the same level as that of Sc(3+) (1.00?eV) and Y(3+) (0.85?eV), while the Lewis acidity of 2?b (1.06?eV) was larger than that of Sc(3+) (1.00?eV) and Y(3+) (0.85?eV). They showed high catalytic ability in carbonyl-compound transformation reactions, such as the Mannich reaction, the Mukaiyama aldol reaction, allylation of aldehydes, the Friedel-Crafts acylation of alkyl aromatic ethers, and cyclotrimerization of ketones. Moreover, the complexes possessed good reusability. On account of their excellent catalytic efficiency, stability, and reusability, the complexes will find broad catalytic applications in organic synthesis. PMID:22504964

  18. Reaction mechanism and metal ion transformation in photocatalytic ozonation of phenol and oxalic acid with Ag(+)/TiO2.

    PubMed

    Chen, Yingying; Xie, Yongbing; Yang, Jun; Cao, Hongbin; Zhang, Yi

    2014-03-01

    Photocatalytic ozonation of phenol and oxalic acid (OA) was conducted with a Ag(+)/TiO2 catalyst and different pathways were found for the degradation of different compounds. Ag(+) greatly promoted the photocatalytic degradation of contaminants due to its role as an electron scavenger. It also accelerated the removal rate of OA in ozonation and the simultaneous process for its complex reaction with oxalate. Phenol could be degraded both in direct ozonation and photolysis, but the TOC removal rates were much higher in the simultaneous processes due to the oxidation of hydroxyl radicals resulting from synergetic effects. The sequence of photo-illumination and ozone exposure in the combined process showed quite different effects in phenol degradation and TOC removal. The synergetic effects in different combined processes were found to be highly related to the properties of the target pollutants. The color change of the solution and TEM result confirmed that Ag(+) was easily reduced and deposited on the surface of TiO2 under photo-illumination, and dissolved again into solution in the presence of ozone. This simple cycle of enrichment and distribution of Ag(+) can greatly benefit the design of advanced oxidation processes, in which the sequences of ozone and photo-illumination can be varied according to the needs for catalyst recycling and the different properties of pollutants. PMID:25079280

  19. Fourier transform infrared study on microemulsion system of potassium salt of bis(2-ethylhexyl) phosphinic acid (HA)

    NASA Astrophysics Data System (ADS)

    Zhou, Weijin; Shi, Nai; Wang, Yi; Chang, Zhiyuan; Wu, JinGuang

    1994-01-01

    To study microemulsion formation in a solvent extraction system is to probe into some basic principles of extraction chemistry in the light of combining extraction chemistry with surface chemistry. In our previous investigations, the microemulsions of the salts of HDEHP and PC88A have been studied systematically by FT-IR. In the experiment, we observed the change of peak positions and intensities of P equals O, P-O-C and P-O-H groups during saponification and hydration, and discovered that the peak of P-O-C splits apart into 1045 and 1075 cm-1. The vibration frequency of the P-O-C group in HDEHP and PC88A is quite close to the symmetric stretching frequency of the POO- group, and thus causes difficulties in the study of their peak position and absorbance variation. For this reason we synthesized bis(2-ethylhexyl) phosphinic acid without the P-O-C group. Infrared spectra in the range of 800 - 4000 cm-1 of this microemulsion system was studied.

  20. Photochemical transformation and photoinduced toxicity reduction of silver nanoparticles in the presence of perfluorocarboxylic acids under UV irradiation.

    PubMed

    Li, Yang; Niu, Junfeng; Shang, Enxiang; Crittenden, John

    2014-05-01

    The impact of perfluorocarboxylic acids (PFCAs) with carbon chain length C2 to C8 on the dissolution, aggregation, reactive oxygen species (ROS) generation, and toxicity of citrate-coated AgNPs was investigated under UV irradiation. The presence of PFCAs decreased dissolution, aggregation, ROS generation, and toxicity of AgNPs because the negatively charged PFCAs sorbed on AgNP surface enhanced their stability. Both dissolution and aggregation rate of AgNPs decreased with chain length of PFCAs under UV irradiation, primarily because PFCAs with longer chain length sorbed on AgNP surface could form thicker coatings. The dissolution of AgNPs followed pseudo-first-order kinetics, and the rate constant decreased from 0.58 h(-1) with C2 to 0.30 h(-1) with C8. The hydrodynamic diameters of AgNPs linearly increased under UV irradiation with aggregation rates ranged from 72.1 to 143.5 nm/h. O2(-) generation was observed in AgNP suspension with quantum yield of 0.12%, but was completely suppressed by PFCAs because they inhibited the interaction between photoelectrons and O2. A linear correlation was established between dissolved Ag(+) and bacterial survival rates of AgNPs with and without PFCAs under UV irradiation. This study highlights the necessity of considering coexisting organic contaminants when investigating the environmental behaviors of AgNPs. PMID:24673243

  1. Collection of VLE data for acid gas---alkanolamine systems using fourier transform infrared spectroscopy. [Vapor-liquid equilibrium

    SciTech Connect

    Bullin, J.A.; Frazier, R.E.

    1992-01-01

    The industrial standard process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines. Inadequate data for vapor--liquid equilibrium (VLE) hinder the industry from converting operations to more energy efficient amine mixtures and conserving energy. Some energy reductions have been realized in the past decade by applying such amine systems as hindered'' amines, methyldiethanolamine (MDEA), and MDEA based amine mixtures. However, the lack of reliable and accurate fundamental VLE data impedes the commercial application of these more efficient alkanolamine systems. The first project objective is to improve the accuracy of vapor--liquid equilibrium measurements at low hydrogen sulfide concentrations. The second project objective is to measure the VLE for amine mixtures. By improving the accuracy of the VLE measurements on MDEA and mixtures with other amines, energy saving can be quickly and confidently implemented in the many existing absorption units already in use. If about 25% of the existing 95.3 billion SCFD gas purification capacity is converted to these new amine systems, the energy savings are estimated to be about 3 [times] 10[sup 14] BTU/yr.

  2. The relationship between fatty acid profiles in milk identified by Fourier transform infrared spectroscopy and onset of luteal activity in Norwegian dairy cattle.

    PubMed

    Martin, A D; Afseth, N K; Kohler, A; Randby, Å; Eknæs, M; Waldmann, A; Dørum, G; Måge, I; Reksen, O

    2015-08-01

    To investigate the feasibility of milk fatty acids as predictors of onset of luteal activity (OLA), 87 lactations taken from 73 healthy Norwegian Red cattle were surveyed over 2 winter housing seasons. The feasibility of using frozen milk samples for dry-film Fourier transform infrared (FTIR) determination of milk samples was also tested. Morning milk samples were collected thrice weekly (Monday, Wednesday, Friday) for the first 10 wk in milk (WIM). These samples had bronopol (2-bromo-2-nitropropane-1,3-diol) added to them before being frozen at -20°C, thawed, and analyzed by ELISA to determine progesterone concentration and the concentrations of the milk fatty acids C4:0, C14:0, C16:0, C18:0, and cis-9 C18:1 as a proportion of total milk fatty acid content using dry-film FTIR, and averaged by WIM. Onset of luteal activity was defined as the first day that milk progesterone concentrations were >3 ng/mL for 2 successive measurements; the study population was categorized as early (n=47) or late (n=40) OLA, using the median value of 21 DIM as the cutoff. Further milk samples were collected 6 times weekly, from morning and afternoon milkings, these were pooled by WIM, and one proportional sample was analyzed fresh for fat, protein, and lactose content by the dairy company Tine SA, using traditional FTIR spectrography in the wet phase of milk. Daily energy-balance calculations were performed in 42 lactations and averaged by WIM. Animals experiencing late OLA had a more negative energy balance in WIM 1, 3, 4, and 5, with the greatest differences been seen in WIM 3 and 4. A higher proportion of the fatty acids were medium chained, C14:0 and C16:0, in the early than in the late OLA group from WIM 1. In WIM 4, the proportion of total fatty acid content that was C16:0 predicted late OLA, with 74% sensitivity and 80% specificity. The long-chain proportion of the fatty acids C18:0 and cis-9 C18:1 were lower in the early than in the late OLA group. Differences were greatest in WIM 4 and 5. Differences in concentrations of cis-9 C18:1 were seen between the groups from WIM 1. No relationship was seen between OLA and milk concentrations of either protein or fat, or between OLA and the milk fat:protein ratio. The differences in milk fatty acid proportions between the 2 groups are most likely related to differences in energy balance. The study shows that frozen milk samples can be tested for fatty acids by FTIR spectroscopy and that FTIR spectroscopy of milk can be used to provide real-time information about cow reproductive function. PMID:26004832

  3. Separation of the enzymes required for transformation of glutamate to. delta. -aminolevulinic acid in extracts of Synechocystis sp. PCC 6803

    SciTech Connect

    Rieble, S.; Beale, S.I. )

    1989-04-01

    In higher plants, algae, and a wide variety of prokaryotes, the tetrapyrrole pigment precursor {delta}-aminolevulinic acid (ALA) is formed from glutamate by a process requiring at least three enzymatic components plus tRNA{sup Glu}, ATP, NADPH, M{sup 2+}, and pyridoxal phosphate. Previous reports have shown that the cyanobacterium Synechocystis sp. PCC 6803 produces ALA via the glutamate pathway. We report here the separation of this activity into three enzymatic fractions. Cells were harvested and broken in a French pressure cell. Protein precipitating between 30-55% (NH{sub 4}){sub 2}SO{sub 4} saturation were separated on Blue-Sepharose into unbound protein (fraction I) and bound protein which was further separated on 2{prime}-5{prime} ADP-agarose into unbound protein (fraction II) and bound protein (fraction III). Reconstitution of ALA-forming activity protein (fraction II) and bound (fraction III). Reconstitution of ALA-forming activity required all three fractions. Only fraction II had the ability to aminoacylate tRNA with glutamate in the presence of ATP and Mg{sup 2+} and therefore contains the glutamyl-tRNA synthetase. After reisolation by phenol extraction, the glutamyl-tRNA could be used as substrate for ALA formation in incubations containing fractions I and III. Only fraction I had the ability to convert synthetic glutamate-1-semialdehyde into ALA. This enzyme activity was 90% inhibited by 5{mu}M gabaculine. The mol wts of the activities in fraction I and II were estimated by Sephadex G-150 gel filtration to be 99,000 and 63,000 (+ 5,000), respectively. The results indicate that the protein components of the ALA-forming pathway in Synechocystis are similar to those of higher plants and eukaryotic algae.

  4. Sources, transformation and fate of particulate amino acids and hexosamines under varying hydrological regimes in the tropical Wenchang/Wenjiao Rivers and Estuary, Hainan, China

    NASA Astrophysics Data System (ADS)

    Unger, Daniela; Herbeck, Lucia S.; Li, Min; Bao, Hongyan; Wu, Ying; Zhang, Jing; Jennerjahn, Tim

    2013-04-01

    The small tropical Wenchang and Wenjiao Rivers on the island of Hainan, tropical China, are affected by effluents from municipal sewage, aquaculture and agriculture, and by contrasting hydrological regimes related to monsoon and tropical storms. In order to obtain information on the sources, transformation and fate of organic matter (OM) we investigated the amount and composition of amino acids and hexosamines as well as the carbon isotope composition in suspended particulate matter (SPM) from the Wenchang/Wenjiao Estuary. SPM was collected along the salinity gradient starting from the river sites, along the lagoon-shaped Bamen Bay to coastal waters during four sampling campaigns between 2006 and 2009. SPM concentrations ranged between 4.7 and 58.2 mg L-1. Apart from highest values after heavy rain events in spring and summer, SPM showed little seasonal variation, but increased with salinity. From SPM POC% (1.2-20.9%), C/N (4.9-16.5) and ?13Corg (-31.5 to -19.5), the molar composition and content of amino acids and hexosamines (8.2-156.2 mg g-1 dry weight) and by comparison with sediments, mangroves, soils and plants we are able to show that soil-derived material, freshwater and marine plankton were the major sources of suspended OM. High POC and amino acid contents were related to primary production sustained by dissolved nutrients to a large extent stemming from municipal and aquaculture effluents. Factor analysis showed that the suite of biogeochemical parameters measured clearly depict the terrestrial vs. marine origin and the freshness/reactivity of OM. The four groups of samples resulting from cluster analysis were basically related to varying hydrological regimes. With respect to the sources, degradation and fate of particulate OM the major factors were: (i) the year round input of labile, amino acid rich riverine OM matter at the freshwater dominated sites, (ii) high input of degraded soil OM after heavy rains with dispersal throughout the estuary and export to the adjacent coastal area, (iii) significant production of labile marine OM especially during summer inside the bay and the (iv) dominance of refractory marine OM during winter and spring season and in the offshore region. While a major part of the fresh OM fuelled by anthropogenic nutrients appears to be stored or recycled inside the bay, periodic torrential rainfalls can lead to a pulsed export of this OM to the coastal area where it may adversely affect seagrass meadows and coral reefs.

  5. Comparison of Diffuse Reflectance Fourier Transform Mid-Infrared and Near-Infrared Spectroscopy with Grating-Based Near-Infrared for the Determination of Fatty Acids in Forages

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Diffuse reflectance Fourier transform mid-infrared (FTMIR) and near infrared spectroscopy (FTNIR) were compared to scanning monochromator-grating-based near infrared spectroscopy (SMNIR), for their ability to quantify fatty acids (FA) in forages. Thirteen different forage cultivars belonging to 11 d...

  6. Role of Cr(iii) deposition during the photocatalytic transformation of hexavalent chromium and citric acid over commercial TiO2 samples.

    PubMed

    Montesinos, V N; Salou, C; Meichtry, J M; Colbeau-Justin, C; Litter, M I

    2016-02-10

    Removal of Cr(vi) and citric acid (Cit) by heterogeneous photocatalytic Cr(vi) transformation under UV light over two commercial TiO2 samples (1 g L(-1)), Evonik P25 and Hombikat UV100, was studied at pH 2 and Cr(vi) concentrations between 0.2 and 3 mM, with a fixed [Cit]0/[Cr(vi)]0 molar ratio (MR) of 2.5. In both cases, up to complete Cr(vi) removal, the temporal profiles of Cr(vi) and Cit were well adjusted to a pseudo-first order rate law with the same rate constant, evidencing that Cr(vi) removal controls the kinetics of the system. Once Cr(vi) is fully removed, Cit degradation continues with a Langmuir-Hinshelwood behaviour. In all cases, the rate constants decreased with increasing [Cr(vi)]0, and time resolved microwave conductivity (TRMC) measurements revealed that this was due to an increasing retention of Cr(iii) on the surface of the photocatalysts, which reduces the lifetime of the electrons. Both kinetic experiments and TRMC measurements confirm that UV100 is not only more efficient than P25 for Cr(vi) and Cit removal, but it is also less influenced by the poisoning of the surface, consistent with its larger specific area. The use of Cit as the sacrificial agent improves the rate and efficiency of the photocatalytic Cr(vi) removal, and also the stability of the photocatalyst by preventing Cr(iii) deposition, due to the formation of soluble Cr(iii)-complexes, envisaged as a general result of the presence of oligocarboxylic acids in the photocatalytic Cr(vi) system. PMID:26753809

  7. Localization of transforming growth factor alpha and its receptor in gastric mucosal cells. Implications for a regulatory role in acid secretion and mucosal renewal.

    PubMed Central

    Beauchamp, R D; Barnard, J A; McCutchen, C M; Cherner, J A; Coffey, R J

    1989-01-01

    Transforming growth factor alpha (TGF alpha) shares with epidermal growth factor (EGF) structural homology (35%), a common cell-surface membrane receptor (TGF alpha/EGF receptor), and a nearly identical spectrum of biological activity, including inhibition of gastric acid secretion. Herein, we report expression of TGF alpha mRNA in normal gastric mucosa of the adult guinea pig, rat, and dog. TGF alpha mRNA was also detected in matched surgically resected gastric mucosa and adjacent gastric carcinoma from 10 patients, and in gastric mucosa adjacent to a benign ulcer from an additional patient. TGF alpha protein was quantitated by radioimmunoassay and was present in tumor and adjacent mucosa. TGF alpha/EGF receptor mRNA was also detected in gastric mucosa from all species studied. Localization of TGF alpha and TGF alpha/EGF receptor mRNA expression was examined in samples of unfractionated guinea pig gastric mucosa and from chief cell-enriched and parietal cell-enriched fractions. All samples exhibited TGF alpha and TGF alpha/EGF receptor expression. The TGF alpha signal was greatest in the parietal cell fraction (5.8-fold increase), but was also enhanced in the chief cell fraction (1.9-fold increase) relative to the unfractionated gastric mucosa. Like TGF alpha expression, TGF alpha/EGF receptor mRNA expression was most intense in the parietal cell-enriched fraction (7.8-fold increase), but was also increased in the chief cell-enriched fraction (2.7-fold increase) relative to the unfractionated guinea pig gastric mucosa. We conclude that TGF alpha and TGF alpha/EGF receptor genes are expressed in normal adult mammalian gastric mucosa. These findings, when interpreted in light of described actions of TGF alpha and EGF, provide evidence that local production of TGF alpha could play an important role in the regulation of acid secretion and mucosal renewal in the stomach. Images PMID:2760208

  8. Chloroplast transformation.

    PubMed

    Lu, Xiao-Mei; Yin, Wei-Bo; Hu, Zan-Min

    2006-01-01

    In this chapter we briefly review the developmental history and current research status of chloroplast transformation and introduce the merits of chloroplast transformation as compared with the nuclear genome transformation. Furthermore, according to the chloroplast transformation achieved in oilseed rape (Brassica napus), we introduce the preparation of explants, transformation methods, system selection, identification methods of the transplastomic plants, and experimental results. The technical points, the bottleneck, and the further research directions of the chloroplast transformation are discussed in the notes. PMID:16673924

  9. In situ monitoring of sulfuric acid decomposition by Fourier transform infrared (FT-IR) spectroscopy in the sulfur iodine thermochemical reaction for the production of hydrogen

    NASA Astrophysics Data System (ADS)

    Rivera, Dion

    2005-11-01

    A potential way to produce large amounts of hydrogen for energy needs is the thermal breakdown of sulfuric acid (H2SO4) to oxygen, water, and sulfur dioxide (SO2). The sulfur dioxide can then be reacted with iodide to produce hydrogen iodide and ultimately hydrogen. In order to maximize the efficiency of the process it would be ideal to make in situ measurements of SO3, SO2, H2SO4, and water in the process stream in order to maximize the efficiency of the system. Fourier transform infrared (FT-IR) spectroscopy is well suited to detection of these gas phase species as they all contain strong infrared modes in the 900 to 3000 wavenumber region, 11 to 3.3 ?m. However, the reactive nature of the gases and the high temperatures at which the reactions are run, 650 to 800 C, makes standard implementation of FT-IR in process monitoring challenging. This is because the infrared detection most be done in a stand off mode and typical window and cell materials used for infrared monitoring will break down under these extreme conditions. This paper presents modifications to typically FT-IR window materials to allow them to be more robust in the environment of interest and gasket materials that can withstand both high temperatures and the oxidative conditions. Infrared spectra of SO2, SO3, and H2SO4 at elevated temperatures obtained with our system and the quantitative results are presented.

  10. Beyond Naphthenic Acids: Environmental Screening of Water from Natural Sources and the Athabasca Oil Sands Industry Using Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Barrow, Mark P.; Peru, Kerry M.; Fahlman, Brian; Hewitt, L. Mark; Frank, Richard A.; Headley, John V.

    2015-09-01

    There is a growing need for environmental screening of natural waters in the Athabasca region of Alberta, Canada, particularly in the differentiation between anthropogenic and naturally-derived organic compounds associated with weathered bitumen deposits. Previous research has focused primarily upon characterization of naphthenic acids in water samples by negative-ion electrospray ionization methods. Atmospheric pressure photoionization is a much less widely used ionization method, but one that affords the possibility of observing low polarity compounds that cannot be readily observed by electrospray ionization. This study describes the first usage of atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (in both positive-ion and negative-ion modes) to characterize and compare extracts of oil sands process water, river water, and groundwater samples from areas associated with oil sands mining activities. When comparing mass spectra previously obtained by electrospray ionization and data acquired by atmospheric pressure photoionization, there can be a doubling of the number of components detected. In addition to polar compounds that have previously been observed, low-polarity, sulfur-containing compounds and hydrocarbons that do not incorporate a heteroatom were detected. These latter components, which are not amenable to electrospray ionization, have potential for screening efforts within monitoring programs of the oil sands.

  11. Beyond Naphthenic Acids: Environmental Screening of Water from Natural Sources and the Athabasca Oil Sands Industry Using Atmospheric Pressure Photoionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry.

    PubMed

    Barrow, Mark P; Peru, Kerry M; Fahlman, Brian; Hewitt, L Mark; Frank, Richard A; Headley, John V

    2015-09-01

    There is a growing need for environmental screening of natural waters in the Athabasca region of Alberta, Canada, particularly in the differentiation between anthropogenic and naturally-derived organic compounds associated with weathered bitumen deposits. Previous research has focused primarily upon characterization of naphthenic acids in water samples by negative-ion electrospray ionization methods. Atmospheric pressure photoionization is a much less widely used ionization method, but one that affords the possibility of observing low polarity compounds that cannot be readily observed by electrospray ionization. This study describes the first usage of atmospheric pressure photoionization Fourier transform ion cyclotron resonance mass spectrometry (in both positive-ion and negative-ion modes) to characterize and compare extracts of oil sands process water, river water, and groundwater samples from areas associated with oil sands mining activities. When comparing mass spectra previously obtained by electrospray ionization and data acquired by atmospheric pressure photoionization, there can be a doubling of the number of components detected. In addition to polar compounds that have previously been observed, low-polarity, sulfur-containing compounds and hydrocarbons that do not incorporate a heteroatom were detected. These latter components, which are not amenable to electrospray ionization, have potential for screening efforts within monitoring programs of the oil sands. PMID:26115966

  12. The pro-fibrotic properties of transforming growth factor on human fibroblasts are counteracted by caffeic acid by inhibiting myofibroblast formation and collagen synthesis.

    PubMed

    Mia, Masum M; Bank, Ruud A

    2016-03-01

    Fibrosis is a chronic disorder affecting many organs. A universal process in fibrosis is the formation of myofibroblasts and the subsequent collagen deposition by these cells. Transforming growth factor beta1 (TGFβ1) plays a major role in the formation of myofibroblasts, e.g. by activating fibroblasts. Currently, no treatments are available to circumvent fibrosis. Caffeic acid phenethyl ester (CAPE) shows a broad spectrum of biological activities, including anti-fibrotic properties in vivo in mice and rats. However, little is known about the direct effects of CAPE on fibroblasts. We have tested whether CAPE is able to suppress myofibroblast formation and collagen formation of human dermal and lung fibroblasts exposed to TGFβ1, and found that this was indeed the case. In fact, the formation of myofibroblasts by TGFβ1 and subsequent collagen formation was completely abolished by CAPE. The same was observed for fibronectin and tenascin C. The lack of myofibroblast formation is likely due to the suppression of GLI1 and GLI2 expression by CAPE because of diminished nuclear SMAD2/3 levels. Post-treatment with CAPE after myofibroblast formation even resulted in a partial reversal of myofibroblasts into fibroblasts and/or reduction in collagen formation. Major discrepancies were seen between mRNA levels of collagen type I and cells stained positive for collagen, underlining the need for protein data in fibrosis studies to make reliable conclusions. PMID:26453399

  13. Geomagnetic storms and telluric currents

    NASA Astrophysics Data System (ADS)

    Silbergleit, V. M.; Larocca, P. A.

    2009-04-01

    For June 12-13, 2005 thegeomagnetic indices AE and Dst, the parameters of the solar wind (speed and pressure) and the Bz component of the interplanetary geomagnetic field are analyzed as indicators of the development of the troubled period. During this period there were significant geomagnetic variations due to geomagnetic substorms and induced currents on the pipeline located in high latitudes, this fact could produce corrosion increases in its structure.

  14. Appell Transformation and Canonical Transforms

    NASA Astrophysics Data System (ADS)

    Torre, Amalia

    2011-07-01

    The interpretation of the optical Appell transformation, as previously elaborated in relation to the free-space paraxial propagation under both a rectangular and a circular cylindrical symmetry, is reviewed. Then, the caloric Appell transformation, well known in the theory of heat equation, is shown to be amenable for a similar interpretation involving the Laplace transform rather than the Fourier transform, when dealing with the 1D heat equation. Accordingly, when considering the radial heat equation, suitably defined Hankel-type transforms come to be involved in the inherent Appell transformation. The analysis is aimed at outlining the link between the Appell transformation and the canonical transforms.

  15. Interdependent genotoxic mechanisms of monomethylarsonous acid: Role of ROS-induced DNA damage and poly(ADP-ribose) polymerase-1 inhibition in the malignant transformation of urothelial cells

    PubMed Central

    Wnek, Shawn M.; Kuhlman, Christopher L.; Camarillo, Jeannie M.; Medeiros, Matthew K.; Liu, Ke J.; Lau, Serrine S.; Gandolfi, A.J.

    2011-01-01

    Exposure of human bladder urothelial cells (UROtsa) to 50 nM of the arsenic metabolite, monomethylarsonous acid (MMAIII), for 12 weeks results in irreversible malignant transformation. The ability of continuous, low-level MMAIII exposure to cause an increase in genotoxic potential by inhibiting repair processes necessary to maintain genomic stability is unknown. Following genomic insult within cellular systems poly(ADP-ribose) polymerase-1 (PARP-1), a zinc finger protein, is rapidly activated and recruited to sites of DNA strand breaks. When UROtsa cells are continuously exposed to 50 nM MMAIII, PARP-1 activity does not increase despite the increase in MMAIII-induced DNA single-strand breaks through 12 weeks of exposure. When UROtsa cells are removed from continuous MMAIII exposure (2 weeks), PARP-1 activity increases coinciding with a subsequent decrease in DNA damage levels. Paradoxically, PARP-1 mRNA expression and protein levels are elevated in the presence of continuous MMAIII indicating a possible mechanism to compensate for the inhibition of PARP-1 activity in the presence of MMAIII. The zinc finger domains of PARP-1 contain vicinal sulfhydryl groups which may act as a potential site for MMAIII to bind, displace zinc ion, and render PARP-1 inactive. Mass spectrometry analysis demonstrates the ability of MMAIII to bind a synthetic peptide representing the zinc-finger domain of PARP-1, and displace zinc from the peptide in a dose-dependent manner. In the presence of continuous MMAIII exposure, continuous 4-week zinc supplementation restored PARP-1 activity levels and reduced the genotoxicity associated with MMAIII. Zinc supplementation did not produce an overall increase in PARP-1 protein levels, decrease the levels of MMAIII-induced reactive oxygen species, or alter Cu-Zn superoxide dismutase levels. Overall, these results present two potential interdependent mechanisms in which MMAIII may increase the susceptibility of UROtsa cells to genotoxic insult and/or malignant transformation: elevated levels of MMAIII-induced DNA damage through the production of reactive oxygen species, and the direct MMAIII-induced inhibition of PARP-1. PMID:21925530

  16. Interdependent genotoxic mechanisms of monomethylarsonous acid: Role of ROS-induced DNA damage and poly(ADP-ribose) polymerase-1 inhibition in the malignant transformation of urothelial cells

    SciTech Connect

    Wnek, Shawn M.; Kuhlman, Christopher L.; Camarillo, Jeannie M.; Medeiros, Matthew K.; Liu, Ke J.; Lau, Serrine S.; Southwest Environmental Health Sciences Center, Department of Pharmacology and Toxicology, The University of Arizona Health Sciences Center, Tucson, AZ 85721 ; Gandolfi, A.J.

    2011-11-15

    Exposure of human bladder urothelial cells (UROtsa) to 50 nM of the arsenic metabolite, monomethylarsonous acid (MMA{sup III}), for 12 weeks results in irreversible malignant transformation. The ability of continuous, low-level MMA{sup III} exposure to cause an increase in genotoxic potential by inhibiting repair processes necessary to maintain genomic stability is unknown. Following genomic insult within cellular systems poly(ADP-ribose) polymerase-1 (PARP-1), a zinc finger protein, is rapidly activated and recruited to sites of DNA strand breaks. When UROtsa cells are continuously exposed to 50 nM MMA{sup III}, PARP-1 activity does not increase despite the increase in MMA{sup III}-induced DNA single-strand breaks through 12 weeks of exposure. When UROtsa cells are removed from continuous MMA{sup III} exposure (2 weeks), PARP-1 activity increases coinciding with a subsequent decrease in DNA damage levels. Paradoxically, PARP-1 mRNA expression and protein levels are elevated in the presence of continuous MMA{sup III} indicating a possible mechanism to compensate for the inhibition of PARP-1 activity in the presence of MMA{sup III}. The zinc finger domains of PARP-1 contain vicinal sulfhydryl groups which may act as a potential site for MMA{sup III} to bind, displace zinc ion, and render PARP-1 inactive. Mass spectrometry analysis demonstrates the ability of MMA{sup III} to bind a synthetic peptide representing the zinc-finger domain of PARP-1, and displace zinc from the peptide in a dose-dependent manner. In the presence of continuous MMA{sup III} exposure, continuous 4-week zinc supplementation restored PARP-1 activity levels and reduced the genotoxicity associated with MMA{sup III}. Zinc supplementation did not produce an overall increase in PARP-1 protein levels, decrease the levels of MMA{sup III}-induced reactive oxygen species, or alter Cu-Zn superoxide dismutase levels. Overall, these results present two potential interdependent mechanisms in which MMA{sup III} may increase the susceptibility of UROtsa cells to genotoxic insult and/or malignant transformation: elevated levels of MMA{sup III}-induced DNA damage through the production of reactive oxygen species, and the direct MMA{sup III}-induced inhibition of PARP-1.

  17. Transforming acidic coiled-coil protein-3 (Tacc3) acts as a negative regulator of Notch signaling through binding to CDC10 /Ankyrin repeats

    PubMed Central

    Bargo, Sharon; Raafat, Ahmed; McCurdy, David; Amirjazil, Idean; Shu, Youmin; Traicoff, June; Plant, Joshua; Vonderhaar, Barbara K.; Callahan, Robert

    2010-01-01

    We have identified the transforming acidic coiled-coil protein-3 (Tacc3) as a binding partner for Notch4/Int3 and were able to show that it binds to the intracellular domain (ICD) of all members of the Notch receptor family. Members of the Tacc family reside at the centrosomes and associates with microtubules. Recent studies suggest that Tacc3 also contributes to the regulation of gene transcription. Tacc3 specifically interacts with the Notch4/Int3 CDC10/Ankyrin repeats and to a lesser extent, with residues C-terminal to these repeats in the ICD. Dual label immunofluorescence of mouse mammary tissue shows Tacc3 co-localizes with the Notch3 ICD. Co-immunoprecipitation of endogenous Notch and Tacc3 proteins from NIH 3T3 cell extracts, lung and mammary gland confirms that these two proteins interact under physiological conditions. In addition, knock down of Tacc3 in NIH 3T3 cells leads to the up-regulation of Hey2, a target gene for Notch signaling. The affinity of Tacc3 binding to Notch4/Int3 ICD is similar to that between Rbpj and Notch4/Int3 ICD. Notch4/Int3 ICD-Tacc3 interaction results in the inhibition of transcription from a Hes1-Luciferase reporter vector in COS-1 cells. The inhibition was reversed in these cells by increasing the levels of Rbpj. Taken together, these results suggest that Tacc3 is a negative regulator of the Notch signaling pathway. PMID:20804727

  18. Transforming acidic coiled-coil protein-3 (Tacc3) acts as a negative regulator of Notch signaling through binding to CDC10/Ankyrin repeats.

    PubMed

    Bargo, Sharon; Raafat, Ahmed; McCurdy, David; Amirjazil, Idean; Shu, Youmin; Traicoff, June; Plant, Joshua; Vonderhaar, Barbara K; Callahan, Robert

    2010-10-01

    We have identified the transforming acidic coiled-coil protein-3 (Tacc3) as a binding partner for Notch4/Int3 and were able to show that it binds to the intracellular domain (ICD) of all members of the Notch receptor family. Members of the Tacc family reside at the centrosomes and associates with microtubules. Recent studies suggest that Tacc3 also contributes to the regulation of gene transcription. Tacc3 specifically interacts with the Notch4/Int3 CDC10/Ankyrin repeats and to a lesser extent, with residues C-terminal to these repeats in the ICD. Dual label immunofluorescence of mouse mammary tissue shows Tacc3 co-localizes with the Notch3 ICD. Co-immunoprecipitation of endogenous Notch and Tacc3 proteins from NIH3T3 cell extracts, lung and mammary gland confirms that these two proteins interact under physiological conditions. In addition, knock down of Tacc3 in NIH3T3 cells leads to the up-regulation of Hey2, a target gene for Notch signaling. The affinity of Tacc3 binding to Notch4/Int3 ICD is similar to that between Rbpj and Notch4/Int3 ICD. Notch4/Int3 ICD-Tacc3 interaction results in the inhibition of transcription from a Hes1-Luciferase reporter vector in COS-1 cells. The inhibition was reversed in these cells by increasing the levels of Rbpj. Taken together, these results suggest that Tacc3 is a negative regulator of the Notch signaling pathway. PMID:20804727

  19. Transforming acidic coiled-coil 3 and Aurora-A interact in human thyrocytes and their expression is deregulated in thyroid cancer tissues.

    PubMed

    Ulisse, Salvatore; Baldini, Enke; Toller, Matteo; Delcros, Jean-Guy; Guého, Aurélie; Curcio, Francesco; De Antoni, Enrico; Giacomelli, Laura; Ambesi-Impiombato, Francesco S; Bocchini, Sarah; D'Armiento, Massimino; Arlot-Bonnemains, Yannick

    2007-09-01

    Aurora-A kinase has recently been shown to be deregulated in thyroid cancer cells and tissues. Among the Aurora-A substrates identified, transforming acidic coiled-coil (TACC3), a member of the TACC family, plays an important role in cell cycle progression and alterations of its expression occur in different cancer tissues. In this study, we demonstrated the expression of the TACC3 gene in normal human thyroid cells (HTU5), and its modulation at both mRNA and protein levels during cell cycle. Its expression was found, with respect to HTU5 cells, unchanged in cells derived from a benign thyroid follicular tumor (HTU42), and significantly reduced in cell lines derived from follicular (FTC-133), papillary (B-CPAP), and anaplastic thyroid carcinomas (CAL-62 and 8305C). Moreover, in 16 differentiated thyroid cancer tissues, TACC3 mRNA levels were found, with respect to normal matched tissues, reduced by twofold in 56% of cases and increased by twofold in 44% of cases. In the same tissues, a correlation between the expression of the TACC3 and Aurora-A mRNAs was observed. TACC3 and Aurora-A interact in vivo in thyroid cells and both proteins localized onto the mitotic structure of thyroid cells. Finally, TACC3 localization on spindle microtubule was no more observed following the inhibition of Aurora kinase activity by VX-680. We propose that Aurora-A and TACC3 interaction is important to control the mitotic spindle organization required for proper chromosome segregation. PMID:17914111

  20. Biocompatible, pH-sensitive AB2 Miktoarm Polymer-Based Polymersomes: Preparation, Characterization, and Acidic pH-Activated Nanostructural Transformation

    PubMed Central

    Yin, Haiqing; Kang, Han Chang; Huh, Kang Moo; Bae, You Han

    2012-01-01

    Motivated by the limitations of liposomal drug delivery systems, we designed a novel histidine-based AB2-miktoarm polymer (mPEG-b-(polyHis)2) equipped with a phospholipid-mimic structure, low cytotoxicity, and pH-sensitivity. Using core-first click chemistry and ring-opening polymerization, mPEG2kDa-b-(polyHis29kDa)2 was successfully synthesized with a narrow molecular weight distribution (1.14). In borate buffer (pH 9), the miktoarm polymer self-assembled to form a nano-sized polymersome with a hydrodynamic radius of 70.2 nm and a very narrow size polydispersity (0.05). At 4.2 mol/mg polymer, mPEG2kDa-b-(polyHis29kDa)2 strongly buffered against acidification in the endolysosomal pH range and exhibited low cytotoxicity on a 5 d exposure. Below pH 7.4 the polymersome transitioned to cylindrical micelles, spherical micelles, and finally unimers as the pH was decreased. The pH-induced structural transition of mPEG2kDa-b-(polyHis29kDa)2 nanostructures may be caused by the increasing hydrophilic weight fraction of mPEG2kDa-b-(polyHis29kDa)2 and can help to disrupt the endosomal membrane through proton buffering and membrane fusion of mPEG2kDa-b-(polyHis29kDa)2. In addition, a hydrophilic model dye, 5(6)-carboxyfluorescein encapsulated into the aqueous lumen of the polymersome showed a slow, sustained release at pH 7.4 but greatly accelerated release below pH 6.8, indicating a desirable pH sensitivity of the system in the range of endosomal pH. Therefore, this polymersome that is based on a biocompatible histidine-based miktoarm polymer and undergoes acid-induced transformations could serve as a drug delivery vehicle for chemical and biological drugs. PMID:23002330

  1. Transforming Schools.

    ERIC Educational Resources Information Center

    Goens, George A.; Clover, Sharon I. R.

    1992-01-01

    Transforming the school as an organization requires change in all its components. More important, transformation connects the technical components with the human elements to create fundamental changes in the ways people perceive, think, and behave. With the community, a Wisconsin school board adopted a school district value statement to be used as

  2. Reading Transformation

    ERIC Educational Resources Information Center

    Reeves, Melinda

    2006-01-01

    The parents of students who attend Decatur High School thought that there was little hope of their kids going on to college. After a year or so in Decatur's reading program, their sons and daughters were both transformed and college bound. In this article, the author describes how Decatur was able to successfully transform their students. Seven

  3. Reading Transformation

    ERIC Educational Resources Information Center

    Reeves, Melinda

    2006-01-01

    The parents of students who attend Decatur High School thought that there was little hope of their kids going on to college. After a year or so in Decatur's reading program, their sons and daughters were both transformed and college bound. In this article, the author describes how Decatur was able to successfully transform their students. Seven…

  4. Comparative study of lanostane-type triterpene acids in different parts of Poria cocos (Schw.) Wolf by UHPLC-Fourier transform MS and UHPLC-triple quadruple MS.

    PubMed

    Wang, Weihao; Dong, Hongjing; Yan, Renyi; Li, Hua; Li, Pengyue; Chen, Ping; Yang, Bin; Wang, Zhimin

    2015-01-01

    Poria cocos (Schw.) Wolf is widely used as a traditional Chinese medicine, and approximately 10% of traditional Chinese medicinal preparations contain this material, according to the Chinese Pharmacopoeia (2010 edition). Although the epidermis (fulingpi in Chinese, or FLP) and the inner parts (baifuling in Chinese, or BFL) of P. cocos had different therapeutic applications in history, studies pertaining to a comparative analysis of their chemical constituents have been scarce. UHPLC-DAD-FT/MS(n) has been used in the current study to identify the triterpene acids present in fungus based on a detailed analysis of the fragmentation behavior of 13 standard compounds. This analysis allowed for the identification of 27 triterpene acids, including five groups of isomers and four potential new compounds. Furthermore, a UHPLC-MS/MS method has been developed for quantifying the amounts of nine bioactive triterpene acids in samples of the FLP and BFL, including three 3,4-seco-lanostane-type triterpene acids. These results revealed significant differences in the amounts of these compounds in the FLP and BFL samples. Principal component analysis and partial least squares discriminant analysis of the results for the FLP and BFL samples clearly demonstrated that dehydrotumulosic acid, trametenolic acid, dehydrotrametenolic acid and poricoic acid A were the main compounds contributing to the clusters in FLP and BFL. The observed differences in the chemical compositions of FLP and BFL could provide some explanation of the differences in their clinic applications. This study represents the first reported comprehensive analysis of lanostane-type triterpene acids in FLP and BFL parts of P. cocos. PMID:25282601

  5. Lightweight transformer

    SciTech Connect

    Swallom, D.W.; Enos, G.

    1990-05-01

    The technical effort described in this report relates to the program that was performed to design, fabricate, and test a lightweight transformer for Strategic Defense Initiative Organization (SDIO) mission requirements. The objectives of this program were two-fold: (1) design and fabricate a lightweight transformer using liquid hydrogen as the coolant; and (2) test the completed transformer assembly with a low voltage, dc power source. Although the full power testing with liquid helium was not completed, the program demonstrated the viability of the design approach. The lightweight transformer was designed and fabricated, and low and moderate power testing was completed. The transformer is a liquid hydrogen cooled air core transformer that uses thin copper for its primary and secondary windings. The winding mass was approximately 12 kg, or 0.03 kg/kW. Further refinements of the design to a partial air core transformer could potentially reduce the winding mass to as low as 4 or 5 kg, or 0.0125 kg/kW. No attempt was made on this program to reduce the mass of the related structural components or cryogenic container. 8 refs., 39 figs., 2 tabs.

  6. Alteration of a single amino acid in the basic domain of Marek's disease virus Meq oncoprotein plays an important role in T-cell transformation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mareks disease virus encoded oncoprotein, Meq, has been shown to play a major role in transformation of T-lymphocytes. We have earlier shown that replacement of the meq gene in the very virulent strain Md5 with that of vaccine strain CVI988/Rispens resulted in virus attenuation in chickens. To dete...

  7. Application of Attenuated Total Reflectance-Fourier Transformed Infrared (ATR-FTIR) Spectroscopy To Determine the Chlorogenic Acid Isomer Profile and Antioxidant Capacity of Coffee Beans.

    PubMed

    Liang, Ningjian; Lu, Xiaonan; Hu, Yaxi; Kitts, David D

    2016-01-27

    The chlorogenic acid isomer profile and antioxidant activity of both green and roasted coffee beans are reported herein using ATR-FTIR spectroscopy combined with chemometric analyses. High-performance liquid chromatography (HPLC) quantified different chlorogenic acid isomer contents for reference, whereas ORAC, ABTS, and DPPH were used to determine the antioxidant activity of the same coffee bean extracts. FTIR spectral data and reference data of 42 coffee bean samples were processed to build optimized PLSR models, and 18 samples were used for external validation of constructed PLSR models. In total, six PLSR models were constructed for six chlorogenic acid isomers to predict content, with three PLSR models constructed to forecast the free radical scavenging activities, obtained using different chemical assays. In conclusion, FTIR spectroscopy, coupled with PLSR, serves as a reliable, nondestructive, and rapid analytical method to quantify chlorogenic acids and to assess different free radical-scavenging capacities in coffee beans. PMID:26725502

  8. Identification of water-soluble heavy crude oil organic-acids, bases, and neutrals by electrospray ionization and field desorption ionization fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Stanford, Lateefah A; Kim, Sunghwan; Klein, Geoffrey C; Smith, Donald F; Rodgers, Ryan P; Marshall, Alan G

    2007-04-15

    We identify water-soluble (23 degrees C) crude oil NSO nonvolatile acidic, basic, and neutral crude oil hydrocarbons by negative-ion ESI and continuous flow FD FT-ICR MS at an average mass resolving power, m/deltam50% = 550,000. Of the 7000+ singly charged acidic species identified in South American crude oil, surprisingly, many are water-soluble, and much more so in pure water than in seawater. The truncated m/z distributions for water-soluble components exhibit preferential molecular weight, size, and heteroatom class influences on hydrocarbon solubility. Acidic water-soluble heteroatomic classes detected at >1% relative abundance include O, O2, O3, O4, OS, O2S, O3S, O4S, NO2, NO3, and NO4. Parent oil class abundance does not directly relate to abundance in the water-soluble fraction. Acidic oxygen-containing classes are most prevalent in the water-solubles, whereas acidic nitrogen-containing species are least soluble. In contrast to acidic nitrogen-containing heteroatomic classes, basic nitrogen classes are water-soluble. Water-soluble heteroatomic basic classes detected at >1% relative abundance include N, NO, NO2, NS, NS2, NOS, NO2S, N2, N2O, N2O2, OS, O2S, and O2S2. PMID:17533826

  9. Triple transformation

    NASA Astrophysics Data System (ADS)

    Khan, Farrukh I.; Schinn, Dustin S.

    2013-08-01

    A new business plan that enables policy transformation and resource mobilization at the national and international level, while improving access to resources, will allow the Green Climate Fund to integrate development goals and action on climate change.

  10. Increase in nervonic acid content in transformed yeast and transgenic plants by introduction of a Lunaria annua L. 3-ketoacyl-CoA synthase (KCS) gene.

    PubMed

    Guo, Yiming; Mietkiewska, Elzbieta; Francis, Tammy; Katavic, Vesna; Brost, Jennifer M; Giblin, Michael; Barton, Dennis L; Taylor, David C

    2009-03-01

    Nervonic acid is a Very Long-Chain Monounsaturated Fatty Acid (VLCMFA), 24:1 Delta15 (cis-tetracos-15-enoic acid) found in the seed oils of Lunaria annua, borage, hemp, Acer (Purpleblow maple) and Tropaeolum speciosum (Flame flower). However, of these, only the "money plant" (Lunaria annua L.) has been studied and grown sparingly for future development as a niche crop and the outlook has been disappointing. Therefore, our goal was to isolate and characterize strategic new genes for high nervonic acid production in Brassica oilseed crops. To this end, we have isolated a VLCMFA-utilizing 3-Keto-Acyl-CoA Synthase (KCS; fatty acid elongase; EC 2.3.1.86) gene from Lunaria annua and functionally expressed it in yeast, with the recombinant KCS protein able to catalyze the synthesis of several VLCMFAs, including nervonic acid. Seed-specific expression of the Lunaria KCS in Arabidopsis resulted in a 30-fold increase in nervonic acid proportions in seed oils, compared to the very low quantities found in the wild-type. Similar transgenic experiments using B. carinata as the host resulted in a 7-10 fold increase in seed oil nervonic acid proportions. KCS enzyme activity assays indicated that upon using (14)C-22:1-CoA as substrate, the KCS activity from developing seeds of transgenic B. carinata was 20-30-fold higher than the low erucoyl-elongation activity exhibited by wild type control plants. There was a very good correlation between the Lun KCS transcript intensity and the resultant 22:1-CoA KCS activity in developing seed. The highest nervonic acid level in transgenic B. carinata expressing the Lunaria KCS reached 30%, compared to 2.8% in wild type plant. In addition, the erucic acid proportions in these transgenic lines were considerably lower than that found in native Lunaria oil. These results show the functional utility of the Lunaria KCS in engineering new sources of high nervonate/reduced erucic oils in the Brassicaceae. PMID:19082744

  11. Molecular distribution, seasonal variation, chemical transformation and sources of dicarboxylic acids and related compounds in atmospheric aerosols at remote marine Gosan site, Jeju Island

    NASA Astrophysics Data System (ADS)

    Kundu, S.; Kawamura, K.; Lee, M.

    2009-12-01

    : A homologous series of C2-C12 α, ω-dicarboxylic acids, ω-oxocarboxylic acids (C2-C9), pyruvic acid and α-dicarbonyls (C2-C3) were detected in atmospheric aerosols collected between April 2003 and April 2004 from remote marine Gosan site (33°29‧ N, 126°16‧ E) located in Jeju Island, South Korea. They were determined using a GC-FID and GC/MS. Total diacid concentration ranged from 130 to 1911 ng m-3 (av. 642 ng m-3), whereas total oxoacid concentration ranged from 7 to 155 ng m-3 (av. 43 ng m-3), and pyruvic acid and α-dicarbonyls ranged from 0.5 to 15 ng m-3 (av. 5 ng m-3) and 2-108 ng m-3 (av. 17.3 ng m-3), respectively. Oxalic (C2) acid was the most abundant in all seasons followed by malonic (C3) or succinic (C4) acid, and phthalic (Ph) acid. The concentration of diacids decreased with an increase in carbon number except for azelaic (C9) acid, which was more abundant than suberic (C8) acid. Glyoxylic acid was predominant ω-oxoacid contributing to 92% of total ω-oxoacid. Total diacids, oxoacids and dicarbonyls showed maximum concentrations in spring and occasionally in winter, while minimum concentrations were observed in summer. Air mass trajectory analysis suggests that either spring or winter maxima can be explained by strong continental outflow associated with cold front passages, while summer minima are associated with warm southerly flows, which transport clean marine air from low latitudes to Jeju Island. The comparison between total diacid concentration level of this study and other study results of urban and remote sites of East Asia reveals that Gosan site is more heavily influenced by the continental outflow from China. The seasonal variation of malonic/succinic (C3/C4), malic/succinic (hC4/C4), fumaric/maleic (F/M), oxalic/pyruvic (C2/Py) and oxalic/Glyoxal (C2/Gly) ratios showed maxima in summer due to an enhanced photo-production and degradation of diacids and related compounds. Throughout all seasons C3/C4 ratio at Gosan site, located between Chinese cities and Chichi-jima Island in Japan was observed higher than those in Chinese cities and lower than that of the Chichi-jima Island, pointing to the formation of diacid during long range transport. The lowest values of adipic/azelaic (C6/C9) and phthalic/azelaic (Ph/C9) were observed as a result of the overwhelming biogenic emission of the precursors (e.g., unsaturated fatty acids) of azelaic acid in summer.In this study, we will also discuss the sources and transport pathways of diacids and related compounds resolved using a hybrid receptor model, potential source contribution function (PSCF) and model results will be compared with available in-situ observations in East Asia.

  12. Psychoanalytic transformations.

    PubMed

    Riolo, Fernando

    2007-12-01

    The author describes how Bion took Freud's conception of dreams as a form of thought and used it as the basis of his theory of transformations. Bion developed an expanded theory of 'dream thought', understood as a process of selection and transformation of sensory and emotional experiences. In this theory, the work of analysis is in turn conceived as a process not only of deciphering symbols, of revealing already existing unconscious meanings, but also of symbol production--of a process for generating thoughts and conferring meaning on experiences that have never been conscious and never been repressed because they have never been 'thought'. Analysis, in its specific operational sense, becomes a system of transformation whereby unconscious somatopsychic processes acquire the conditions for representability and become capable of translation into thoughts, words and interpretations. The rules of transformation applied by the patient in his representations and those applied by the analyst in his interpretations have the same importance for the analytic process as those described by Freud for the process of dreaming. The author discusses the broad categories of transformation adduced by Bion (rigid motion, projective, and in hallucinosis) and introduces some further distinctions within them. PMID:18055372

  13. TERATOGENIC EFFECTS OF RETINOIC ACID ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR AND TRANSFORMING GROWTH FACTOR-ALPHA

    EPA Science Inventory

    Background: EGF and TGF regulate cell proliferation and differentiation in the embryo. The induction of cleft palate (CP) by all trans retinoic acid (RA) was associated with altered expression of TGF, EGF receptor and binding of EGF. The present study uses knockout (KO) mice to e...

  14. ATR-Fourier-transform mid-infrared spectroscopy for determination of trans fatty acids in ground cereal products without oil extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    ATR-FTIR spectroscopy was investigated as a method for analysis of trans fatty acids (FA) in cereal products without oil extraction. Spectra were obtained with an ATR-FTIR spectrometer using ground samples pressed onto the diamond ATR surface and trans FA measured by a modification of AOAC Method 9...

  15. ATR-FOURIER TRANSFORM MID-INFRARED SPECTROSCOPY FOR DETERMINATION OF TRANS FATTY ACIDS IN GROUND CEREAL PRODUCTS WITHOUT OIL EXTRACTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since FDA amended the rules for food labeling to include trans fatty acids (TFA), there has been a continued interest in development of optimized methods for determining TFA in foods. Traditional chromatographic methods are time-consuming and solvent based. Alternatively, spectroscopic methods invol...

  16. SHARP transformation

    NASA Astrophysics Data System (ADS)

    Wyatt, Stephan

    2004-08-01

    The U.S. Navy"s SHAred Reconnaissance Pod (SHARP) employs the Recon/Optical, Inc. (ROI) CA-279 dual spectral band (visible/IR) digital cameras operating from an F-18E/F aircraft to perform low-to-high altitude reconnaissance missions. SHARP has proven itself combat worthy, with a rapid transition from development to operational deployment culminating in a highly reliable and effective reconnaissance capability for joint forces operating in Operation Iraqi Freedom (OIF). The U.S. Navy"s intelligence, surveillance and reconnaissance (ISR) roadmap transforms the SHARP system from being solely an independent reconnaissance sensor to a node in the growing Joint ISR network. ROI and the U.S. Navy have combined their resources to ensure the system"s transformation continues to follow the ISR road map. Pre-planned product improvements (P3I) for the CA-270 camera systems will lead the way in that transformation.

  17. Transformative Assessment

    ERIC Educational Resources Information Center

    Popham, W. James

    2008-01-01

    If you're at all skeptical that "formative assessment" is just another buzzword, then here's a book that will change the way you think about the role that formative assessment can play in transforming education into a more powerful and positive process. Renowned expert W. James Popham clarifies what formative assessment really is, why it's right

  18. Transformation Time

    ERIC Educational Resources Information Center

    Berry, John N., III

    2007-01-01

    The program for the march by librarians on America's capital for the American Library Association (ALA) conference is predictably loaded with lobbying, legislation, and DC tours. It also abounds with professional opportunity and reflects the impact of Leslie Burger, one of the most activist ALA presidents in recent history. Her "Transformation"…

  19. Transforming Schools.

    ERIC Educational Resources Information Center

    Cookson, Peter W., Jr., Ed.; Schneider, Barbara, Ed.

    The authors in this book address the issues that relate to the crisis in American education and review some of the proposed solutions. To transform education, schools must be examined as social systems that are interrelated with families, communities, and the world of work. Following the introduction, section 1, "Conditions for Educational…

  20. Transforming Schools.

    ERIC Educational Resources Information Center

    Cookson, Peter W., Jr., Ed.; Schneider, Barbara, Ed.

    The authors in this book address the issues that relate to the crisis in American education and review some of the proposed solutions. To transform education, schools must be examined as social systems that are interrelated with families, communities, and the world of work. Following the introduction, section 1, "Conditions for Educational

  1. Transformation & Metamorphosis

    ERIC Educational Resources Information Center

    Lott, Debra

    2009-01-01

    The sculptures of Canadian artist Brian Jungen are a great inspiration for a lesson on creating new forms. Jungen transforms found objects into unique creations without fully concealing their original form or purpose. Frank Stella's sculpture series, including "K.132,2007" made of stainless steel and spray paint, is another great example of

  2. Transformation & Metamorphosis

    ERIC Educational Resources Information Center

    Lott, Debra

    2009-01-01

    The sculptures of Canadian artist Brian Jungen are a great inspiration for a lesson on creating new forms. Jungen transforms found objects into unique creations without fully concealing their original form or purpose. Frank Stella's sculpture series, including "K.132,2007" made of stainless steel and spray paint, is another great example of…

  3. Dynamic kinetic resolution of 1,3-dihydro-2H-isoindole-1-carboxylic acid methyl ester: asymmetric transformations toward isoindoline carbamates.

    PubMed

    Morn-Ramallal, Roberto; Gotor-Fernndez, Vicente; Laborda, Pedro; Sayago, Francisco J; Cativiela, Carlos; Gotor, Vicente

    2012-04-01

    Asymmetric syntheses of isoindoline carbamates have been successfully achieved through enzyme-mediated dynamic kinetic resolution processes and without requirement of metal or acid-base catalyst for the substrate racemization. Optically active carbamates were obtained in good yields and an excellent degree of stereoselectivity when Pseudomonas cepacia lipase (PSL) was used as biocatalyst, with diallyl or dibenzyl carbonates being both adequate reagents in alkoxycarbonylation reactions. PMID:22417293

  4. RF transformer

    DOEpatents

    Smith, James L.; Helenberg, Harold W.; Kilsdonk, Dennis J.

    1979-01-01

    There is provided an improved RF transformer having a single-turn secondary of cylindrical shape and a coiled encapsulated primary contained within the secondary. The coil is tapered so that the narrowest separation between the primary and the secondary is at one end of the coil. The encapsulated primary is removable from the secondary so that a variety of different capacity primaries can be utilized with one secondary.

  5. Transformative learning.

    PubMed

    Nemec, Patricia B

    2012-12-01

    The whole point of teaching and training is to have the learners leave in some way different from how they came in-more skilled, more knowledgeable, more self-aware. Transformative learning refers to dramatic change, where the learner achieves a shift in perspective. This shift results from a critical examination of one's own assumptions, values, and beliefs, and of the foundations and expectations of the system in which one operates. Educators are in the change business, and educators focused on implementing psychiatric rehabilitation, recovery-oriented services, and person-centered planning are in the transformative learning business. The shift from a traditional medical model to a recovery perspective, the shift from "illness" to "disability" to "wellness," and the shift from risk prevention to promoting opportunities for growth all require "standing outside ourselves" and looking at a "stark and highlighted picture" of the all-too-common status quo of mental health services today. With the right approach, learners can be developed, encouraged, disrupted, and transformed. PMID:23276245

  6. Complementary DNA cloning of the pear 1-aminocyclopropane-1-carboxylic acid oxidase gene and agrobacterium-mediated anti-sense genetic transformation.

    PubMed

    Qi, Jing; Dong, Zhen; Zhang, Yu-Xing

    2015-12-01

    The aim of the present study was to genetically modify plantlets of the Chinese yali pear to reduce their expression of ripening-associated 1-aminocyclopropane-1-carboxylic acid oxidase (ACO) and therefore increase the shelf-life of the fruit. Primers were designed with selectivity for the conserved regions of published ACO gene sequences, and yali complementary DNA (cDNA) cloning was performed by reverse transcription quantitative polymerase chain reaction (PCR). The obtained cDNA fragment contained 831 base pairs, encoding 276 amino acid residues, and shared no less than 94% nucleotide sequence identity with other published ACO genes. The cDNA fragment was inversely inserted into a pBI121 expression vector, between the cauliflower mosaic virus 35S promoter and the nopaline synthase terminator, in order to construct the anti‑sense expression vector of the ACO gene; it was transfected into cultured yali plants using Agrobacterium LBA4404. Four independent transgenic lines of pear plantlets were obtained and validated by PCR analysis. A Southern blot assay revealed that there were three transgenic lines containing a single copy of exogenous gene and one line with double copies. The present study provided germplasm resources for the cultivation of novel storage varieties of pears, therefore providing a reference for further applications of anti‑sense RNA technology in the genetic improvement of pears and other fruit. PMID:26460204

  7. Effect of temperature on short chain fatty acids (SCFAs) accumulation and microbiological transformation in sludge alkaline fermentation with Ca(OH)? adjustment.

    PubMed

    Li, XiaoLing; Peng, YongZhen; Ren, NanQi; Li, BaiKun; Chai, TongZhi; Zhang, Liang

    2014-09-15

    The effects of temperatures (15-55 C) on the alkaline fermentation of sewage sludge were investigated in semi-continuous stirred tank reactors (semi - CSTR) at the pH of 10. The highest soluble chemical oxygen demand (SCOD) yield was obtained at 55 C (764.2 mg/(gVS L d)), while the highest short chain fatty acids (SCFAs) yield was observed at 35 C (319.8 mg/(gVS L d)), 1.5 times higher than SCFAs yield at 55 C (209.5 mg/(gVS L d)). The proportion of the intercellular organic substances being transferred to the slime layer of sludge flocs increased from 29% at 15 C to 54% at 55 C. But only a small part of soluble organic substances in the slime layers was converted to SCFAs at 55 C. The dewaterability of sludge was better at 35 C than that at 55 C. Microbiological community analysis showed the acid-producing microorganisms at the medium temperatures (25 C and 35 C) were more diverse and abundant than those at the low (15 C) and high temperatures (55 C). Clodtridium and Bacillus in Firmicutes and Gamma proteobacterium in Proteobacteria were the dominant functional bacterial species for high SCFA accumulation. PMID:24880243

  8. Photo-transformation of pedogenic humic acid and consequences for Cd(II), Cu(II) and Pb(II) speciation and bioavailability to green microalga.

    PubMed

    Worms, Isabelle A M; Adenmatten, David; Miville, Pascal; Traber, Jacqueline; Slaveykova, Vera I

    2015-11-01

    Humic substances (HS) play key role in toxic metal binding and protecting aquatic microorganisms from metal-induced stress. Any environmental changes that could alter HS concentration and reactivity can be expected to modify metal complexation and thus affect metal speciation and bioavailability to microalgae. The present study explores the influence of increased solar irradiance on the chemical structures and molecular weight of Elliott soil humic acid (EHA) and the associated consequences for Cd(II), Cu(II) and Pb(II) complexation and intracellular metal content in microalga. The results demonstrate that high radiance doses induce an oxidation of EHA with a formation of low molecular weight acids, an increase of -OH and -COOH group abundance, and a drop in EHA hydrodynamic size and molecular weight. The photo-induced structural changes are accompanied with a release of metal from M-EHA complexes and narrowing their size distribution, which in turn results in an increase of the intracellular Cd, Cu and Pb contents in microalga Chlamydomonas reinhardtii in agreement with the measured free metal ions concentrations. PMID:25563161

  9. Synthesis of MnO{sub 2} phases from LiMn{sub 2}O{sub 4} in aqueous acidic media. Mechanisms of phase transformations, reactivity, and effect of Bi species

    SciTech Connect

    Larcher, D.; Courjal, P.; Gerand, B.; Blyr, A.; Pasquier, A. du; Tarascon, J.M.; Urbina, R.H.

    1998-10-01

    The nature of the phases obtained by acid digestion of LiMn{sub 2}O{sub 4} phases prepared at 800 C from a mixture of MnO{sub 2} (EMD) and Li{sub 2}CO{sub 3} was investigated. The authors found that the complete transformation toward {alpha}-MnO{sub 2} and then {gamma}-MnO{sub 2} observed for LiMn{sub 2}O{sub 4} treated in 2.5 M H{sub 2}SO{sub 4} for 24 h at 95 C is highly dependent on the amount of water in the reaction medium. The {lambda} {yields} {alpha}/{gamma} transformation was found to be the result of a dissolution-crystallization mechanism that can be completely avoided by adding a soluble Bi, Pb, or Tl salt to the reaction medium. By coupling energy dispersive spectroscopy analysis, infrared spectroscopy, and potentiometric titration, the authors demonstrated the presence of Bi species adsorbed at the surface of the {lambda}-MnO{sub 2} oxide thus modifying its reactivity. In addition, the kinetics of the {lambda} {yields} {alpha}/{gamma} phase transformation was found to depend on the amount of added Bi salt, suggesting the complexing role of Bi toward Mn (Bi-Mn complexes), thereby affecting the crystallization step of the reaction. The same treatment was applied to LiMn{sub 2}O{sub 4} in the presence of a Bi salt in anhydrous electrolyte (LiPF{sub 6}/ethylene carbonate/dimethyl carbonate). In this case, the spinel oxide dissolution slows down and BiF{sub 3} precipitates. With respect to recent findings about the mechanisms involved in the electrochemical capacity failure at elevated temperature in Li-ion LiMn{sub 2}O{sub 4} cells, these results open new alternatives to solve this recurrent problem.

  10. OligoPred: a web-server for predicting homo-oligomeric proteins by incorporating discrete wavelet transform into Chou's pseudo amino acid composition.

    PubMed

    Qiu, Jian-Ding; Suo, Sheng-Bao; Sun, Xing-Yu; Shi, Shao-Ping; Liang, Ru-Ping

    2011-09-01

    In vivo, some proteins exist as monomers (single polypeptide chains) and others as oligomers. Not like monomers, oligomers are composed of two or more chains (subunits) that are associated with each other through non-covalent interactions and, occasionally, through disulfide bonds. These proteins are the structural components of various biological functions, including cooperative effects, allosteric mechanisms and ion-channel gating. However, with the dramatic increase in the number of protein sequences submitted to the public data bank, it is important for both basic research and drug discovery research to acquire the possible knowledge about homo-oligomeric attributes of their interested proteins in a timely manner. In this paper, a high-throughput method, combined support vector machines with discrete wavelet transform, has been developed to predict the protein homo-oligomers. The total accuracy obtained by the re-substitution test, jackknife test and independent dataset test are 99.94%, 96.17% and 96.18%, respectively, showing that the proposed method of extracting feature from the protein sequences is effective and feasible for predicting homo-oligomers. The online service is available at http://bioinfo.ncu.edu.cn/Services.aspx. PMID:21802968

  11. An experimental investigation of Lewis acid-base interactions of liquid carbon dioxide using Fourier Transform Infrared (FT-IR) spectroscopy

    NASA Astrophysics Data System (ADS)

    Reilly, J. T.; Bokis, C. P.; Donohue, M. D.

    1995-05-01

    Presented here is an investigation into the solvent properties of liquid carbon dioxide by means of FT-IR spectroscopy. A high-pressure, circulation-type apparatus was designed and built specifically for this study. The spectra for the combination bands for carbon dioxide show that there are interactions between methanol and carbon dioxide. However, the spectra of the fundamental O-D vibration of deuterated methanol in liquid carbon dioxide indicate that there is no hydrogen bonding. Therefore. we conclude that the interactions between carbon dioxide and methanol are Lewis acid-base interactions rather than hydrogen bonding. This conclusion is supported by experiments where acetone is introduced into the CO2/methanol- d binary system. FT-IR measurements show that acetone hydrogen bonds with deuterated methanol.

  12. Hamlet's Transformation.

    NASA Astrophysics Data System (ADS)

    Usher, P. D.

    1997-12-01

    William Shakespeare's Hamlet has much evidence to suggest that the Bard was aware of the cosmological models of his time, specifically the geocentric bounded Ptolemaic and Tychonic models, and the infinite Diggesian. Moreover, Shakespeare describes how the Ptolemaic model is to be transformed to the Diggesian. Hamlet's "transformation" is the reason that Claudius, who personifies the Ptolemaic model, summons Rosencrantz and Guildenstern, who personify the Tychonic. Pantometria, written by Leonard Digges and his son Thomas in 1571, contains the first technical use of the word "transformation." At age thirty, Thomas Digges went on to propose his Perfit Description, as alluded to in Act Five where Hamlet's age is given as thirty. In Act Five as well, the words "bore" and "arms" refer to Thomas' vocation as muster-master and his scientific interest in ballistics. England's leading astronomer was also the father of the poet whose encomium introduced the First Folio of 1623. His oldest child Dudley became a member of the Virginia Company and facilitated the writing of The Tempest. Taken as a whole, such manifold connections to Thomas Digges support Hotson's contention that Shakespeare knew the Digges family. Rosencrantz and Guildenstern in Hamlet bear Danish names because they personify the Danish model, while the king's name is latinized like that of Claudius Ptolemaeus. The reason Shakespeare anglicized "Amleth" to "Hamlet" was because he saw a parallel between Book Three of Saxo Grammaticus and the eventual triumph of the Diggesian model. But Shakespeare eschewed Book Four, creating this particular ending from an infinity of other possibilities because it "suited his purpose," viz. to celebrate the concept of a boundless universe of stars like the Sun.

  13. Rotary Transformer

    NASA Technical Reports Server (NTRS)

    McLyman, Colonel Wm. T.

    1996-01-01

    None given. From first Par: Many spacecraft (S/C) and surface rovers require the transfer of signals and power across rotating interfaces. Science instruments, antennas and solar arrays are elements needing rotary power transfer for certain (S/C) configurations. Delivery of signal and power has mainly been done by using the simplest means, the slip ring approach. This approach, although simple, leaves debris generating noise over a period of time...The rotary transformer is a good alternative to slip rings for signal and power transfer.

  14. TRANSFORMER APPARATUS

    DOEpatents

    Wolfgang, F.; Nicol, J.

    1962-11-01

    Transformer apparatus is designed for measuring the amount of a paramagnetic substance dissolved or suspended in a diamagnetic liquid. The apparatus consists of a cluster of tubes, some of which are closed and have sealed within the diamagnetic substance without any of the paramagnetic material. The remaining tubes are open to flow of the mix- ture. Primary and secondary conductors are wrapped around the tubes in such a way as to cancel noise components and also to produce a differential signal on the secondaries based upon variations of the content of the paramagnetic material. (AEC)

  15. Quantitative Analysis of Long Chain Fatty Acids Present in a Type I Kerogen Using Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry: Compared with BF3/MeOH Methylation/GC-FID

    NASA Astrophysics Data System (ADS)

    Kamga, Albert W.; Behar, Fancoise; Hatcher, Patrick G.

    2014-05-01

    Long chain fatty acids (LCFAs) are present in various natural samples and are easily detectable using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FT-ICR-MS) in negative ion mode. The capability of the ESI-FT-ICR-MS for quantifying LCFAs was evaluated by performing a standard addition followed by an internal standard methodology to several kerogen extracts using n-C20 fatty acid as standard. As the concentration of the standard increased, the magnitude of its peak ( m/z 311.29525) increased linearly but with two separate slopes, leaving the entire mass spectra relatively unchanged, which shows evidence of reproducibility. Response factors of other LCFAs are obtained using a standard addition approach. We employed five LCFA standards ( n-C15, n-C19, n-C24, n-C26, and n-C30) with different carbon numbers. This allowed us to determine the response factor of all fatty acids (with carbon number between 15 and 30) by plotting the slope of each standard versus its carbon number. With the observed response factors and use of the internal standard, the concentrations of LCFAs in four kerogen extracts were measured by ESI-FT-ICR-MS and compared with those from GC-FID. The carbon number distribution obtained by ESI-FT-ICR-MS matched well the GC-FID distribution (5%-50%) with the exception of C16 and C18, considering that ESI-FT-ICR-MS does not differentiate between normal and branched LCFAs, whereas GC-FID does. This allows one to quantitatively compare samples with a relatively similar matrix for specific compounds such as LCFAs with no need of time-consuming derivatization procedures. Moreover, the calibration can be extended to higher carbon numbers with ESI-FT-ICR-MS, beyond the capabilities of GC/MS.

  16. Hydrolytic Amino Acids Employed as a Novel Organic Nitrogen Source for the Preparation of PGPF-Containing Bio-Organic Fertilizer for Plant Growth Promotion and Characterization of Substance Transformation during BOF Production

    PubMed Central

    Feng, Chenglong; Ran, Wei; Yu, Guanghui; Zhang, Yingjun; Shen, Qirong

    2016-01-01

    Opportunity costs seriously limit the large-scale production of bio-organic fertilizers (BOFs) both in China and internationally. This study addresses the utilization of amino acids resulting from the acidic hydrolysis of pig corpses as organic nitrogen sources to increase the density of TrichodermaharzianumT-E5 (a typical plant growth-promoting fungi, PGPF). This results in a novel, economical, highly efficient and environmentally friendly BOF product. Fluorescence excitation-emission matrix (EEM) spectroscopy combined with fluorescence regional integration (FRI) was employed to monitor compost maturity levels, while pot experiments were utilized to test the effects of this novel BOF on plant growth. An optimization experiment, based on response surface methodologies (RSMs), showed that a maximum T-E5 population (3.72 × 108 ITS copies g−1) was obtained from a mixture of 65.17% cattle manure compost (W/W), 19.33% maggot manure (W/W), 15.50% (V/W)hydrolytic amino acid solution and 4.69% (V/W) inoculum at 28.7°C after a 14 day secondary solid fermentation. Spectroscopy analysis revealed that the compost transformation process involved the degradation of protein-like substances and the formation of fulvic-like and humic-like substances. FRI parameters (PI, n, PII, n, PIII, n and PV, n) were used to characterize the degree of compost maturity. The BOF resulted in significantly higher increased chlorophyll content, shoot length, and shoot and root dry weights of three vegetables (cucumber, tomato and pepper) by 9.9%~22.4%, 22.9%~58.5%, 31.0%~84.9%, and 24.2%~34.1%, respectively. In summary, this study presents an operational means of increasing PGPF T-E5 populations in BOF to promote plant growth with a concomitant reduction in production cost. In addition, a BOF compost maturity assessment using fluorescence EEM spectroscopy and FRI ensured its safe field application. PMID:26974549

  17. Hydrolytic Amino Acids Employed as a Novel Organic Nitrogen Source for the Preparation of PGPF-Containing Bio-Organic Fertilizer for Plant Growth Promotion and Characterization of Substance Transformation during BOF Production.

    PubMed

    Zhang, Fengge; Meng, Xiaohui; Feng, Chenglong; Ran, Wei; Yu, Guanghui; Zhang, Yingjun; Shen, Qirong

    2016-01-01

    Opportunity costs seriously limit the large-scale production of bio-organic fertilizers (BOFs) both in China and internationally. This study addresses the utilization of amino acids resulting from the acidic hydrolysis of pig corpses as organic nitrogen sources to increase the density of TrichodermaharzianumT-E5 (a typical plant growth-promoting fungi, PGPF). This results in a novel, economical, highly efficient and environmentally friendly BOF product. Fluorescence excitation-emission matrix (EEM) spectroscopy combined with fluorescence regional integration (FRI) was employed to monitor compost maturity levels, while pot experiments were utilized to test the effects of this novel BOF on plant growth. An optimization experiment, based on response surface methodologies (RSMs), showed that a maximum T-E5 population (3.72 × 108 ITS copies g-1) was obtained from a mixture of 65.17% cattle manure compost (W/W), 19.33% maggot manure (W/W), 15.50% (V/W)hydrolytic amino acid solution and 4.69% (V/W) inoculum at 28.7°C after a 14 day secondary solid fermentation. Spectroscopy analysis revealed that the compost transformation process involved the degradation of protein-like substances and the formation of fulvic-like and humic-like substances. FRI parameters (PI, n, PII, n, PIII, n and PV, n) were used to characterize the degree of compost maturity. The BOF resulted in significantly higher increased chlorophyll content, shoot length, and shoot and root dry weights of three vegetables (cucumber, tomato and pepper) by 9.9%~22.4%, 22.9%~58.5%, 31.0%~84.9%, and 24.2%~34.1%, respectively. In summary, this study presents an operational means of increasing PGPF T-E5 populations in BOF to promote plant growth with a concomitant reduction in production cost. In addition, a BOF compost maturity assessment using fluorescence EEM spectroscopy and FRI ensured its safe field application. PMID:26974549

  18. Distinguishing of Ile/Leu amino acid residues in the PP3 protein by (hot) electron capture dissociation in Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Kjeldsen, Frank; Haselmann, Kim F; Srensen, Esben S; Zubarev, Roman A

    2003-03-15

    In hot electron capture dissociation (HECD), multiply protonated polypeptides fragment upon capturing approximately 11-eV electrons. The excess of energy upon the primary c, z* cleavage induces secondary fragmentation in z* fragments. The resultant w ions allow one to distinguish between the isomeric Ile and Leu residues. The analytical utility of HECD is evaluated using tryptic peptides from the bovine milk protein PP3 containing totally 135 amino acid residues. Using a formal procedure for Ile/Leu (Xle) residue assignment, the identities of 20 out of 25 Xle residues (80%) were determined. The identity of an additional two residues could be correctly guessed from the absence of the alternative w ions, and only two residues, for which neither expected nor alternative w ions were observed, remained unassigned. Reinspection of conventional ECD spectra also revealed the presence of Xle w ions, although at lower abundances, with 44% of all Xle residues distinguished. Using a dispenser cathode as an electron source, identification of four out of five Xle residues in a 2.7-kDa peptide was possible with one acquisition 2 s long, with identification of all five residues by averaging of five such acquisitions. Unlike the case of high-energy collision-induced dissociation, no d ions were observed in the HECD of tryptic peptides. PMID:12659185

  19. Preparation of hydrophilic poly(lactic acid) tissue engineering scaffold via (PLA)-(PLA-b-PEG)-(PEG) solution casting and thermal-induced surface structural transformation.

    PubMed

    Zhu, Xiaomin; Zhong, Tian; Huang, Ran; Wan, Ajun

    2015-01-01

    Porous poly(lactic acid) (PLA) tissue engineering scaffolds with a hydrophilic surface assembled by polyethylene glycol aggregations were prepared by the solvent casting/particulate leaching method from (PLA)-(PLA-b-PEG)-(PEG) blend solution, where the PLA-b-PEG block polymer serves as an amphiphilic glue between two phases. A thermal recrystallization process was inserted before leaching to induce a phase separation, which subsequently squeezes out PEG to form a hydrophilic shell. Characterizations of XRD and DSC indicated the composition and mixing states of materials. The water contact angle test qualitatively presented the excellent hydrophilicity compared to the pure PLA or PLA-PEG simple blend scaffold. The scanning electron microscope results confirmed the formation of porous structure of [Formula: see text] pore size, with an observable phase separation on the surface. The scaffold was degraded in PBS at [Formula: see text], and the degradation exhibits a three-stage behavior, which evidenced the amphiphilically glued phase separations. PMID:26324121

  20. Collection of VLE data for acid gas---alkanolamine systems using fourier transform infrared spectroscopy. Phase 2, October 1, 1991--September 30, 1992

    SciTech Connect

    Bullin, J.A.; Frazier, R.E.

    1992-12-01

    The industrial standard process for the purification of natural gas is to remove acid gases, mainly hydrogen sulfide and carbon dioxide, by the absorption and reaction of these gases with alkanolamines. Inadequate data for vapor--liquid equilibrium (VLE) hinder the industry from converting operations to more energy efficient amine mixtures and conserving energy. Some energy reductions have been realized in the past decade by applying such amine systems as ``hindered`` amines, methyldiethanolamine (MDEA), and MDEA based amine mixtures. However, the lack of reliable and accurate fundamental VLE data impedes the commercial application of these more efficient alkanolamine systems. The first project objective is to improve the accuracy of vapor--liquid equilibrium measurements at low hydrogen sulfide concentrations. The second project objective is to measure the VLE for amine mixtures. By improving the accuracy of the VLE measurements on MDEA and mixtures with other amines, energy saving can be quickly and confidently implemented in the many existing absorption units already in use. If about 25% of the existing 95.3 billion SCFD gas purification capacity is converted to these new amine systems, the energy savings are estimated to be about 3 {times} 10{sup 14} BTU/yr.

  1. All-trans-retinoic Acid Modulates the Plasticity and Inhibits the Motility of Breast Cancer Cells: ROLE OF NOTCH1 AND TRANSFORMING GROWTH FACTOR (TGFβ).

    PubMed

    Zanetti, Adriana; Affatato, Roberta; Centritto, Floriana; Fratelli, Maddalena; Kurosaki, Mami; Barzago, Maria Monica; Bolis, Marco; Terao, Mineko; Garattini, Enrico; Paroni, Gabriela

    2015-07-17

    All-trans-retinoic acid (ATRA) is a natural compound proposed for the treatment/chemoprevention of breast cancer. Increasing evidence indicates that aberrant regulation of epithelial-to-mesenchymal transition (EMT) is a determinant of the cancer cell invasive and metastatic behavior. The effects of ATRA on EMT are largely unknown. In HER2-positive SKBR3 and UACC812 cells, showing co-amplification of the ERBB2 and RARA genes, ATRA activates a RARα-dependent epithelial differentiation program. In SKBR3 cells, this causes the formation/reorganization of adherens and tight junctions. Epithelial differentiation and augmented cell-cell contacts underlie the anti-migratory action exerted by the retinoid in cells exposed to the EMT-inducing factors EGF and heregulin-β1. Down-regulation of NOTCH1, an emerging EMT modulator, is involved in the inhibition of motility by ATRA. Indeed, the retinoid blocks NOTCH1 up-regulation by EGF and/or heregulin-β1. Pharmacological inhibition of γ-secretase and NOTCH1 processing also abrogates SKBR3 cell migration. Stimulation of TGFβ contributes to the anti-migratory effect of ATRA. The retinoid switches TGFβ from an EMT-inducing and pro-migratory determinant to an anti-migratory mediator. Inhibition of the NOTCH1 pathway not only plays a role in the anti-migratory action of ATRA; it is relevant also for the anti-proliferative activity of the retinoid in HCC1599 breast cancer cells, which are addicted to NOTCH1 for growth/viability. This effect is enhanced by the combination of ATRA and the γ-secretase inhibitor N-(N-(3,5-difluorophenacetyl)-l-alanyl)-S-phenylglycine t-butyl ester, supporting the concept that the two compounds act at the transcriptional and post-translational levels along the NOTCH1 pathway. PMID:26018078

  2. EDITORIAL: Transformation optics Transformation optics

    NASA Astrophysics Data System (ADS)

    Shalaev, Vladimir M.; Pendry, John

    2011-02-01

    Metamaterials are artificial materials with versatile properties that can be tailored to fit almost any practical need and thus go well beyond what can be obtained with `natural' materials. Recent progress in developing optical metamaterials allows unprecedented extreme control over the flow of light at both the nano- and macroscopic scales. The innovative field of transformation optics, which is enabled by metamaterials, inspired researchers to take a fresh look at the very foundations of optics and helped to create a new paradigm for the science of light. Similar to general relativity, where time and space are curved, transformation optics shows that the space for light can also be bent in an almost arbitrary way. Most importantly, the optical space can be designed and engineered, opening up the fascinating possibility of controlling the flow of light with nanometer spatial precision. This new paradigm enables a number of novel optical devices guiding how, using metamaterials, the space for light can be curved in a pre-designed and well-controlled way. Metamaterials which incorporate the innovative theories of transformation optics are pertinent to the important areas of optical cloaking, optical black holes, super-resolution imaging, and other sci-fi-like devices. One such exciting device is an electromagnetic cloak that can bend light around itself, similar to the flow of water around a stone, making invisible both the cloak and the object hidden inside. Another important application is a flat hyperlens that can magnify the nanometer-scale features of an object that cannot be resolved with conventional optics. This could revolutionize the field of optical imaging, for instance, because such a meta-lens could become a standard add-on tool for microscopes. By enabling nanoscale resolution in optical microscopy, metamaterial-based transformation optics could allow one to literally see extremely small objects with the eye, including biological cells, viruses, and possibly even DNA molecules. Light-concentrating devices, such as the optical black hole, can be used for efficient solar light collection in photovoltaic elements for renewable energy. With the dramatic advances in micro- and nanofabrication methods, we are presented with the opportunity to control light in a way that was not possible with the materials provided to us by nature. In an artificial pattern of sub-wavelength elements, the propagation of electromagnetic energy can be defined by an equivalent spatial and spectral dispersion of effective dielectric and magnetic properties. These synthetic structures, which can be fabricated with a desired spatial distribution of effective permittivity epsilon(r) and permeability ?(r), offer a unique potential to guide and control the flow of electromagnetic energy in such an engineered optical space. No longer are we constrained by the electromagnetic response of natural materials and their chemical compounds. Instead, we can tailor the shape and size of the structural units of the metamaterials, or tune their composition and morphology to provide new functionality.

  3. Macromolecular Synthesis in Newly Transformed Cells of Bacillus subtilis

    PubMed Central

    McCarthy, Charlotte; Nester, E. W.

    1967-01-01

    The capacity of newly transformed cells of Bacillus subtilis to synthesize deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein has been determined by following the kinetics of suicide after their exposure to tritiated precursors of each of these macromolecules. Competent cells, whether transformed or not, are heterogeneous with respect to DNA synthesis. About 40 to 50% are latent in DNA synthesis. This latency may persist for 2.5 to 3 hr since transformants are resistant to thymineless death for this period after DNA addition. The remainder of the transformants synthesize DNA at one-half the rate of the cells of the total population. Synthesis of stable RNA does not occur at an appreciable rate in newly transformed cells. Newly transformed cells, however, do synthesize protein extensively, as demonstrated by the lethality of incorporated tritiated amino acids. Either chloramphenicol or actinomycin D treatment during the time of exposure to the tritiated amino acid prevented the suicide of transformants. PMID:4961411

  4. Solvent-induced syntheses, crystal structures, magnetic properties, and single-crystal-to-single-crystal transformation of azido-Cu(II) coordination polymers with 2-naphthoic acid as co-ligand.

    PubMed

    Liu, Xiangyu; Cen, Peipei; Li, Hui; Ke, Hongshan; Zhang, Sheng; Wei, Qing; Xie, Gang; Chen, Sanping; Gao, Shengli

    2014-08-01

    Based on the solvent-induced effect, three new azido-copper coordination polymers--[Cu(2-na)(N3)] (1), [Cu(2-na)(N3)] (2), and [Cu(2-na)(N3)(C2H5OH)] (3) (where 2-na = 2-naphthoic acid)--have been successfully prepared. Structure analysis shows that the Cu(II) cations in compounds 1-3 present tetra-, penta-, and hexa-coordination geometries, respectively. Compound 1 is a well-isolated one-dimensional (1D) chain with the EO-azido group, while 2 is an isomer of 1 and exhibits a two-dimensional (2D) layer involving the EE-azido group. Thermodynamically, density functional theory (DFT) calculation reveals that 2 occupies the stable state and 1 locates in the metastable state. Compound 3 consists of a 1D chain with triple bridging mode, which is derived from 1, and undergoes a single-crystal-to-single-crystal transformation by soaking in ethanol solvent; the powdery product of 1, namely 1b, could be yielded after the dealcoholization of compound 3. Magnetic measurements indicate that compounds 1-3 perform strong intrachain ferromagnetic interactions, experiencing long-range magnetic ordering and slow magnetic relaxation. Compound 1 features the metamagnetic behavior with a transition temperature of 15 K, while 2 and 3 display spin glass behavior with the phase transition temperatures of 15 and 12 K, respectively. Magneto-structure relationships are investigated as well. PMID:25014208

  5. Practical example of the correction of Fourier-transform spectra for detector nonlinearity.

    PubMed

    Abrams, M C; Toon, G C; Schindler, R A

    1994-09-20

    HgCdTe photoconductive detectors can display a nonlinear response when illuminated. In interferometric applications, this behavior must be accounted for in the data transformation process to avoid errors in the measurement of the spectral distribution of the incident radiation. A model for the distortion of the interferogram is proposed and applied to solar observations made by the Atmospheric Trace Molecule Spectroscopy (ATMOS) Fourier-transform spectrometer during orbital sunrise and sunset from the Space Shuttle. Empirical estimation of the dc current level is necessary for this instrument, and satisfactory nonlinearity correction is obtained for several of the primary ATMOS optical filters. For ATMOS broadband optical filters that cover more than one half the alias bandwidth, the model is inadequate because of the presence of antialiasing electronic filters within the instrument, and it is necessary to resort to estimation and subtraction of the residual baseline offset. In either case the remaining base line offsets are typically smaller than 1%, which is satisfactory, although offset remains a significant systematic source of error in the estimation of the abundance of telluric and solar constituents from the spectra. PMID:20941162

  6. Transforming giants.

    PubMed

    Kanter, Rosabeth Moss

    2008-01-01

    Large corporations have long been seen as lumbering, inflexible, bureaucratic--and clueless about global developments. But recently some multinationals seem to be transforming themselves: They're engaging employees, moving quickly, and introducing innovations that show true connection with the world. Harvard Business School's Kanter ventured with a research team inside a dozen global giants--including IBM, Procter & Gamble, Omron, CEMEX, Cisco, and Banco Real--to discover what has been driving the change. After conducting more than 350 interviews on five continents, she and her colleagues came away with a strong sense that we are witnessing the dawn of a new model of corporate power: The coordination of actions and decisions on the front lines now appears to stem from widely shared values and a sturdy platform of common processes and technology, not from top-down decrees. In particular, the values that engage the passions of far-flung workforces stress openness, inclusion, and making the world a better place. Through this shift in what might be called their guidance systems, the companies have become as creative and nimble as much smaller ones, even while taking on social and environmental challenges of a scale that only large enterprises could attempt. IBM, for instance, has created a nonprofit partnership, World Community Grid, through which any organization or individual can donate unused computing power to research projects and see what is being done with the donation in real time. IBM has gained an inspiring showcase for its new technology, helped business partners connect with the company in a positive way, and offered individuals all over the globe the chance to contribute to something big. PMID:18271317

  7. Hadamard transform imaging

    SciTech Connect

    Morris, M.D.

    1992-01-01

    We have constructed a Hadamard transform Raman microscopic imaging system, and have developed it to a high definition (64K pixel) technique. We have demonstrated multispectral Raman imaging and developed the first three-dimensional (digital confocal) Raman imaging. We have explored the systematic errors in Hadamard multiplexing techniques and developed corrections. We have used our Raman microscope techniques to explore defect distributions on graphite electrodes and damage effects on SERS-activated silver electrodes. We have used the microprobe capabilities of our instrument to investigate the kinetics of polyacrylamide formation in electrolysis capabilities. We have worked closely with a manufacture of holographic displays to develop and incorporate holographic filters and holographic beam splitters into Raman spectrographs and microscopes. Finally, we have developed Hadamard multiplexing techniques for densitometric measurements of protein or nucleic acid blots.

  8. Anaerobic transformation of TNT

    SciTech Connect

    Kulpa, C.F.; Roopathy, R.

    1995-12-31

    Most studies on the microbial metabolism of nitroaromatic compounds have used aerobic tempts to degrade nitroaromatics under aerobic microorganisms. In many cases attempts to degrade nitroaromatics under aerobic conditions results in no mineralization and only superficial modifications of the structure. However, under anaerobic sulfate-reducing conditions, the nitroaromatic compounds undergo a series of reductions with the formation of amino compounds. Trinitrotoluene under sulfate-reducing conditions is reduced to triaminotoluene presumably by the enzyme nitrite reductase, which is commonly found in many Desulfovibrio spp. The removal of nitrate from trinitrotoluene is achieved by a series of reductive reactions with the production of ammonia and toluene by Desulfovibrio sp. (B strain). Similar metabolic processes could be applied to other nitroaromatic compounds like nitrobenzene, nitrobenzoic acids, nitrophenols, and aniline. This presentation will review the data supporting the anaerobic transformation of TNT and other nitroaromatics.

  9. Physiological factors affecting transformation of Azotobacter vinelandii.

    PubMed Central

    Page, W J; Sadoff, H L

    1976-01-01

    Cells of Azotobacter vinelandii (ATCC 12837) can be transformed by exogenous deoxyribonucleic acid towards the end of exponential growth. Transformation occurs at very low frequencies when the deoxyribonucleic acid is purified or when the transformation is carried out in liquid medium. Optimal transformation occurs on plates of Burk nitrogen-free glucose medium containing either high phosphate (10 mM) or low calcium (0 to 0.29 mM) content. Higher levels of calcium are inhibitory, whereas magnesium ions are essential for transformation and growth. Extracellular polymer and capsule are increasingly inhibitory to transformation and are most abundant when the calcium content of the medium is high. Transformation is optimal at pH 7.0 to 7.1 and at 30 C, conditions which also coincide with minimal extracellular polymer production. Nonencapsulated strains are excellent transformation recipients. Glycine-induced pleomorphism reduces the transformation frequency and the degree of inhibition is dependent on the phosphate concentration of the medium. Rifampin resistance and shifts from adenine, hypoxanthine, uracil, and nitrogenase auxotrophy to prototrophy can be achieved. Although single marker transfer is always greater than double marker transfer, the data suggest that rifampin resistance is linked to hypoxanthine, adenine and uracil protorophy at intervals of increasing distance. Rifampin resistance did not appear to be linked to nitrogenase. PMID:3492

  10. GEMAS: prediction of solid-solution phase partitioning coefficients (Kd) for oxoanions and boric acid in soils using mid-infrared diffuse reflectance spectroscopy.

    PubMed

    Janik, Leslie J; Forrester, Sean T; Soriano-Disla, Jos M; Kirby, Jason K; McLaughlin, Michael J; Reimann, Clemens

    2015-02-01

    The authors' aim was to develop rapid and inexpensive regression models for the prediction of partitioning coefficients (Kd), defined as the ratio of the total or surface-bound metal/metalloid concentration of the solid phase to the total concentration in the solution phase. Values of Kd were measured for boric acid (B[OH]3(0)) and selected added soluble oxoanions: molybdate (MoO4(2-)), antimonate (Sb[OH](6-)), selenate (SeO4(2-)), tellurate (TeO4(2-)) and vanadate (VO4(3-)). Models were developed using approximately 500 spectrally representative soils of the Geochemical Mapping of Agricultural Soils of Europe (GEMAS) program. These calibration soils represented the major properties of the entire 4813 soils of the GEMAS project. Multiple linear regression (MLR) from soil properties, partial least-squares regression (PLSR) using mid-infrared diffuse reflectance Fourier-transformed (DRIFT) spectra, and models using DRIFT spectra plus analytical pH values (DRIFT?+?pH), were compared with predicted log K(d?+?1) values. Apart from selenate (R(2) ?=?0.43), the DRIFT?+?pH calibrations resulted in marginally better models to predict log K(d?+?1) values (R(2) ?=?0.62-0.79), compared with those from PSLR-DRIFT (R(2) ?=?0.61-0.72) and MLR (R(2) ?=?0.54-0.79). The DRIFT?+?pH calibrations were applied to the prediction of log K(d?+?1) values in the remaining 4313 soils. An example map of predicted log K(d?+?1) values for added soluble MoO4(2-) in soils across Europe is presented. The DRIFT?+?pH PLSR models provided a rapid and inexpensive tool to assess the risk of mobility and potential availability of boric acid and selected oxoanions in European soils. For these models to be used in the prediction of log K(d?+?1) values in soils globally, additional research will be needed to determine if soil variability is accounted on the calibration. PMID:25476926

  11. The Funk transform as a Penrose transform

    NASA Astrophysics Data System (ADS)

    Bailey, Toby N.; Eastwood, Michael G.; Gover, A. Rod; Mason, Lionel J.

    1999-01-01

    The Funk transform is the integral transform from the space of smooth even functions on the unit sphere S2[subset or is implied by][open face R]3 to itself defined by integration over great circles. One can regard this transform as a limit in a certain sense of the Penrose transform from [open face C][open face P]2 to [open face C][open face P]*ast;2. We exploit this viewpoint by developing a new proof of the bijectivity of the Funk transform which proceeds by considering the cohomology of a certain involutive (or formally integrable) structure on an intermediate space. This is the simplest example of what we hope will prove to be a general method of obtaining results in real integral geometry by means of complex holomorphic methods derived from the Penrose transform.

  12. Enhanced downregulation of transforming growth factor‑β2 in rat retinal pigment epithelium cells by adeno‑associated virus‑mediated ribonucleic acid interference combined with ultrasound or microbubbles.

    PubMed

    Li, Hongli; Wan, Caifeng; Du, Lianfang; Li, Fenghua

    2015-02-01

    The present study was designed to determine the efficiency and safety of ultrasound (US) and/or US contrast agent microbubbles (MBs) in the delivery of type 2 recombinant adeno-associated virus‑delivered transforming growth factor‑β2 short hairpin ribonucleic acid encoding the enhanced green fluorescent protein gene (rAAV2‑TGFβ2 shRNA‑EGFP) and the downregulation of TGFβ2 in rat retinal pigment epithelium (RPE‑J) cells. The effects of US and/or MBs on the delivery of rAAV2‑EGFP and rAAV2‑TGFβ2 shRNA‑EGFP were evaluated by fluorescence microscopy and flow cytometry. The potential toxicity of cell viability under various US or MB conditions was assessed by CellTiter 96® AQueous One solution cell proliferation assay. The level of TGFβ2 mRNA in RPE‑J cells under various conditions was estimated by reverse transcription‑quantitative polymerase chain reaction analysis. The results obtained demonstrated that low-intensity US (0.5 W/cm2 and 30 sec) or SonoVue (MB:cell ratio, 40:1) increased the delivery efficiency of rAAV2‑EGFP and rAAV2‑TGFβ2 shRNA‑EGFP to RPE‑J cells, whereas the combination of US with MBs did not further increase but instead decreased rAAV transfection. Under the optimal conditions of rAAV delivery, enhanced TGFβ2 gene silencing with a combination of US or SonoVue with rAAV2‑TGFβ2 shRNA resulted in a significant decrease in mRNA levels compared with rAAV2‑TGFβ2 shRNA alone. US or SonoVue was used safely to enhance the delivery of rAAV2‑TGFβ2 shRNA to RPE‑J cells. A combination of the biological (rAAV2‑TGFβ2 shRNA) and physical (US or SonoVue) approaches downregulated the mRNA level of TGFβ2 more effectively. PMID:25370502

  13. Transforming the Way We Teach Function Transformations

    ERIC Educational Resources Information Center

    Faulkenberry, Eileen Durand; Faulkenberry, Thomas J.

    2010-01-01

    In this article, the authors discuss "function," a well-defined rule that relates inputs to outputs. They have found that by using the input-output definition of "function," they can examine transformations of functions simply by looking at changes to input or output and the respective changes to the graph. Applying transformations to the input

  14. Transformation of lipids in activated sludge.

    PubMed

    Dueholm, T E; Andreasen, K H; Nielsen, P H

    2001-01-01

    Transformation of lipids in activated sludge treatment plants is of interest for two reasons: lipids contribute 30-40% of the chemical oxygen demand (COD) in wastewater, and they may stimulate the growth of filamentous microorganisms in nutrient removal activated sludge plants. The transformation of lipids was investigated under aerobic and anoxic conditions by measuring the oxygen and nitrate uptake rates (OUR and NUR). The maximal OUR and NUR of long-chain fatty acid was found to be at the same level as acetate indicating that long-chain fatty acid was as easily consumable. However, the adsorption of long-chain fatty acid to surfaces of sludge flocs made it difficult to determine initial uptake rates of long-chain fatty acids. It was not possible to describe the hydrolysis rate of triacylglyceride by OUR and NUR to long-chain fatty acids because the hydrolysis rate was very slow. For a better description of the processes involved in transformation of lipids, a conceptual model was suggested. The processes in the suggested model were the adsorption/desorption of both triacylglyceride, and long-chain fatty acid onto surfaces of sludge flocs, hydrolysis of triacylglyceride by lipases and the uptake of long-chain fatty acid by bacteria under various conditions. The model can be helpful to structure design and evaluation of activated sludge experiment with lipids. PMID:11379087

  15. Pantothenic acid biosynthesis in zymomonas

    DOEpatents

    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.

  16. Microbial Transformation of Arsenic

    NASA Astrophysics Data System (ADS)

    Stolz, J. F.

    2004-12-01

    Whether the source is natural or anthropogenic, it has become evident that arsenic is readily transformed by a great diversity of microbial species and has a robust biogeochemical cycle. Arsenic cycling primarily involves the oxidation of As(III) and the reduction of As(V). Over thirty arsenite oxidizing prokaryotes have been reported and include alpha, beta, and gamma Proteobacteria , Deinocci and Crenarchaeota. At least twenty species of arsenate-respiring prokaryotes are now known and include Crenarchaeota, thermophilic bacteria, low and high G+C gram positive bacteria, and gamma, delta, and epsilon Proteobacteria. These organisms are metabolically diverse, and depending on the species, capable of using other terminal electron acceptors (e.g., nitrate, selenate, fumarate, sulfate). In addition to inorganic forms (e.g., sodium arsenate) organoarsenicals can be utilized as a substrate. The feed additive roxarsone (3-nitro-4-hydroxyphenyl arsonic acid) has been shown to readily degrade leading to the release of inorganic arsenic (e.g., As(V)). Degradation proceeds via the cleavage of the arsenate functional group or the reduction of the nitro functional group and deamination. The rapid degradation (within 3 days) of roxarsone by Clostridium sp. strain OhILAs appears to follow the latter pathway and may involve Stickland reactions. The activities of these organisms affect the speciation and mobilization of arsenic, ultimately impacting water quality.

  17. Equations For Rotary Transformers

    NASA Technical Reports Server (NTRS)

    Salomon, Phil M.; Wiktor, Peter J.; Marchetto, Carl A.

    1988-01-01

    Equations derived for input impedance, input power, and ratio of secondary current to primary current of rotary transformer. Used for quick analysis of transformer designs. Circuit model commonly used in textbooks on theory of ac circuits.

  18. 28-Channel rotary transformer

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1981-01-01

    Transformer transmits power and digital data across rotating interface. Array has many parallel data channels, each with potential l megabaud data rate. Ferrite-cored transformers are spaced along rotor; airgap between them reduces crosstalk.

  19. Chemical Transformation Simulator

    EPA Science Inventory

    The Chemical Transformation Simulator (CTS) is a web-based, high-throughput screening tool that automates the calculation and collection of physicochemical properties for an organic chemical of interest and its predicted products resulting from transformations in environmental sy...

  20. Achieving Perspective Transformation.

    ERIC Educational Resources Information Center

    Nowak, Jens

    Perspective transformation is a consciously achieved state in which the individual's perspective on life is transformed. The new perspective serves as a vantage point for life's actions and interactions, affecting the way life is lived. Three conditions are basic to achieving perspective transformation: (1) "feeling" experience, i.e., getting in

  1. Mechanisms of transformation toughening

    SciTech Connect

    Olson, G.B.

    1992-02-01

    Modelling the thermodynamics and kinetics of isothermal martensitic transformation under stress, transformation toughening in austenitic steels, and dispersed phase transformation plasticity in low alloy steels are discussed briefly in this progress report for Doe Grant DE-FG02-88ER45365.

  2. Method for production of petroselinic acid and OMEGA12 hexadecanoic acid in transgenic plants

    DOEpatents

    Ohlrogge, J.B.; Cahoon, E.B.; Shanklin, J.; Somerville, C.R.

    1995-07-04

    The present invention relates to a process for producing lipids containing the fatty acid, petroselinic acid, in plants. The production of petroselinic acid is accomplished by genetically transforming plants which do not normally accumulate petroselinic acid with a gene for a {omega}12 desaturase from another species which does normally accumulate petroselinic acid. 19 figs.

  3. Method for production of petroselinic acid and OMEGA12 hexadecanoic acid in transgenic plants

    DOEpatents

    Ohlrogge, John B.; Cahoon, Edgar B.; Shanklin, John; Somerville, Christopher R.

    1995-01-01

    The present invention relates to a process for producing lipids containing the fatty acid petroselinic acid in plants. The production of petroselinic acid is accomplished by genetically transforming plants which do not normally accumulate petroselinic acid with a gene for a .omega.12 desaturase from another species which does normally accumulate petroselinic acid.

  4. Note: Tesla transformer damping

    NASA Astrophysics Data System (ADS)

    Reed, J. L.

    2012-07-01

    Unexpected heavy damping in the two winding Tesla pulse transformer is shown to be due to small primary inductances. A small primary inductance is a necessary condition of operability, but is also a refractory inefficiency. A 30% performance loss is demonstrated using a typical "spiral strip" transformer. The loss is investigated by examining damping terms added to the transformer's governing equations. A significant alteration of the transformer's architecture is suggested to mitigate these losses. Experimental and simulated data comparing the 2 and 3 winding transformers are cited to support the suggestion.

  5. Note: Tesla transformer damping.

    PubMed

    Reed, J L

    2012-07-01

    Unexpected heavy damping in the two winding Tesla pulse transformer is shown to be due to small primary inductances. A small primary inductance is a necessary condition of operability, but is also a refractory inefficiency. A 30% performance loss is demonstrated using a typical "spiral strip" transformer. The loss is investigated by examining damping terms added to the transformer's governing equations. A significant alteration of the transformer's architecture is suggested to mitigate these losses. Experimental and simulated data comparing the 2 and 3 winding transformers are cited to support the suggestion. PMID:22852736

  6. Inhibition of Transformation of Bacillus subtilis by Heavy Metals

    PubMed Central

    Groves, David J.; Wilson, Gary A.; Young, Frank E.

    1974-01-01

    Mercuric ions, as well as organomercuric ions and cadmium ions, can inhibit deoxyribonucleic acid-mediated transformation in Bacillus subtilis 168 without decreasing the viability of the total population. Differences in the inhibition of transformation by mercuric ions are identifiable on a temporal and concentration dependence basis. Sensitivity to low concentrations (9.2 10?8 M) appears early in the uptake of deoxyribonucleic acid before the transformed markers have become insensitive to deoxyribonuclease. Resistance to low concentrations of Hg2+ is kinetically indistinguishable from the requirement for magnesium in the transformation process. This inactivation is not reversed by the mercury-binding compound glutathione. Sensitivity to mercuric ions at a higher concentration (5.52 10?7 M) occurs after the donor deoxyribonucleic acid has become insensitive to deoxyribonuclease. These complex interactions between mercuric ions and the process of transformation are discussed. PMID:4213689

  7. Transformation of Haemophilus influenzae by plasmid RSF0885

    SciTech Connect

    Notani, N.K.; Setlow, J.K.; McCarthy, D.; Clayton, N.L.

    1981-12-01

    Plasmid RSF0885, which conferred ampicillin resistance, transformed competent Haemophilus influenzae cells with low efficiency (maximun, less than 0.01%). As judged by competition experiments and uptake of radioactivity, plasmid RSF0885 deoxyribonucleic acid was taken up into competent H. influenzae cells several orders of magnitude less efficiently than H. influenzae chromosomal deoxyribonucleic acid. Plasmid RSF0885 transformed cells with even lower efficiency than could be accounted for by the low uptake. Transformation was not affected by rec-1 and rec-2 mutations in the recipient, and strains cured of the plasmid did not show increased transformation. Plasmid molecules cut once with a restriction enzyme that made blunt ends did not transform. Transformation was favored by the closed circular form of the plasmid.

  8. Transformation in Escherichia coli: cryogenic preservation of competent cells.

    PubMed Central

    Morrison, D A

    1977-01-01

    Escherichia coli cells prepared for transformation by treatment with cold 0.1 M CaCl2 remained viable and competent after storage at -82 degrees C in 15% glycerol; thawed-cell samples yielded up to 10(6) transformants per microgram of plasmid deoxyribonucleic acid. PMID:334731

  9. Magnetically Controlled Variable Transformer

    NASA Technical Reports Server (NTRS)

    Kleiner, Charles T.

    1994-01-01

    Improved variable-transformer circuit, output voltage and current of which controlled by use of relatively small current supplied at relatively low power to control windings on its magnetic cores. Transformer circuits of this type called "magnetic amplifiers" because ratio between controlled output power and power driving control current of such circuit large. This ratio - power gain - can be as large as 100 in present circuit. Variable-transformer circuit offers advantages of efficiency, safety, and controllability over some prior variable-transformer circuits.

  10. Program Transformation in HATS

    SciTech Connect

    Winter, V.L.

    1999-02-24

    HATS is a general purpose syntax derivation tree based transformation system in which transformation sequences are described in special purpose language. A powerful feature of this language is that unification is an explicit operation. By making unification explicit, an elegant framework arises in which to express complex application conditions which in turn enables refined control strategies to be realized. This paper gives an overview of HATS, focusing especially on the framework provided by the transformation language and its potential with respect to control and general purpose transformation.

  11. Concepts and transformational knowledge.

    PubMed

    Zaki, S R; Homa, D

    1999-09-01

    The effect of exposure to principled change in concept formation was investigated in four experiments. In Experiment 1, participants were trained on either patterns that transformed systematically or control patterns that were distorted randomly. Training on transformational patterns produced concepts that were more resistant to false intrusions and decay. Experiment 2 separated the relative influences of transformational knowledge and pairwise similarity. Participants were able to identify the next pattern in a transformational sequence even though the foils were closer to the training patterns. Experiment 3 investigated whether participants use transformational information in a speeded categorization task. Participants were faster at classifying patterns that continued a transformational path than patterns that fell off the path, only if they had trained on the transformational patterns in a systematic order. Experiment 4 used multidimensional scaling to explore the psychological structure of transformational knowledge following training. Analyses revealed clear evidence of a transformational path with systematic training. Implications for theories of similarity and categorization are discussed. PMID:10462456

  12. [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. PMID:20649031

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

    TOXLINE Toxicology Bibliographic Information

    Zhang H; Chen X; Jin Z; Liao G; Wu X; Du J; Cao X

    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.

  14. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1977-01-01

    Technical memorandum includes transformer area product numbers, which are used to summarize dimensional and electrical properties of C-cores, pot cores, lamination, powder cores, and tape-wound cores. To aid in core selection, comparison of five common core materials is presented to indicate their influence on overall transformer efficiency and weight.

  15. Direct current transformer

    NASA Technical Reports Server (NTRS)

    Khanna, S. M.; Urban, E. W. (Inventor)

    1979-01-01

    A direct current transformer in which the primary consists of an elongated strip of superconductive material, across the ends of which is direct current potential is described. Parallel and closely spaced to the primary is positioned a transformer secondary consisting of a thin strip of magnetoresistive material.

  16. Transformation optics and metamaterials.

    PubMed

    Chen, Huanyang; Chan, C T; Sheng, Ping

    2010-05-01

    Underpinned by the advent of metamaterials, transformation optics offers great versatility for controlling electromagnetic waves to create materials with specially designed properties. Here we review the potential of transformation optics to create functionalities in which the optical properties can be designed almost at will. This approach can be used to engineer various optical illusion effects, such as the invisibility cloak. PMID:20414221

  17. Support Principals, Transform Schools

    ERIC Educational Resources Information Center

    Aguilar, Elena; Goldwasser, Davina; Tank-Crestetto, Kristina

    2011-01-01

    The Transformational Coaching Team in Oakland Unified School District provides differentiated, sustained, job-embedded support to the district's school leaders. In this article, members of the team describe how they work with principals to transform the culture of schools. Student achievement data show above-average improvement in schools in which

  18. Biochemical transformation of coals

    DOEpatents

    Lin, M.S.; Premuzic, E.T.

    1999-03-23

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed. 7 figs.

  19. A Transformation Called "Twist"

    ERIC Educational Resources Information Center

    Hwang, Daniel

    2010-01-01

    The transformations found in secondary mathematics curriculum are typically limited to stretches and translations (e.g., ACARA, 2010). Advanced students may find the transformation, twist, to be of further interest. As most available resources are written for professional-level readers, this article is intended to be an introduction accessible to

  20. Genetic Transformation of Bacteria.

    ERIC Educational Resources Information Center

    Moss, Robert.

    1991-01-01

    An activity in which students transform an ampicillin-sensitive strain of E. coli with a plasmid containing a gene for ampicillin resistance is described. The procedure for the preparation of competent cells and the transformation of competent E. coli is provided. (KR)

  1. Disc piezoelectric ceramic transformers.

    PubMed

    Erhart, Jiri; P?lpn, Petr; Dole?ek, Roman; Psota, Pavel; Ldl, Vt

    2013-08-01

    In this contribution, we present our study on disc-shaped and homogeneously poled piezoelectric ceramic transformers working in planar-extensional vibration modes. Transformers are designed with electrodes divided into wedge, axisymmetrical ring-dot, moonie, smile, or yin-yang segments. Transformation ratio, efficiency, and input and output impedances were measured for low-power signals. Transformer efficiency and transformation ratio were measured as a function of frequency and impedance load in the secondary circuit. Optimum impedance for the maximum efficiency has been found. Maximum efficiency and no-load transformation ratio can reach almost 100% and 52 for the fundamental resonance of ring-dot transformers and 98% and 67 for the second resonance of 2-segment wedge transformers. Maximum efficiency was reached at optimum impedance, which is in the range from 500 ? to 10 k?, depending on the electrode pattern and size. Fundamental vibration mode and its overtones were further studied using frequency-modulated digital holographic interferometry and by the finite element method. Complementary information has been obtained by the infrared camera visualization of surface temperature profiles at higher driving power. PMID:25004532

  2. Biochemical transformation of coals

    DOEpatents

    Lin, Mow S. (Rocky Point, NY); Premuzic, Eugene T. (East Moriches, NY)

    1999-03-23

    A method of biochemically transforming macromolecular compounds found in solid carbonaceous materials, such as coal is provided. The preparation of new microorganisms, metabolically weaned through challenge growth processes to biochemically transform solid carbonaceous materials at extreme temperatures, pressures, pH, salt and toxic metal concentrations is also disclosed.

  3. Support Principals, Transform Schools

    ERIC Educational Resources Information Center

    Aguilar, Elena; Goldwasser, Davina; Tank-Crestetto, Kristina

    2011-01-01

    The Transformational Coaching Team in Oakland Unified School District provides differentiated, sustained, job-embedded support to the district's school leaders. In this article, members of the team describe how they work with principals to transform the culture of schools. Student achievement data show above-average improvement in schools in which…

  4. Deployment & Market Transformation (Brochure)

    SciTech Connect

    Not Available

    2012-04-01

    NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

  5. Two Different Squeeze Transformations

    NASA Technical Reports Server (NTRS)

    Han, D. (Editor); Kim, Y. S.

    1996-01-01

    Lorentz boosts are squeeze transformations. While these transformations are similar to those in squeezed states of light, they are fundamentally different from both physical and mathematical points of view. The difference is illustrated in terms of two coupled harmonic oscillators, and in terms of the covariant harmonic oscillator formalism.

  6. Adaptive Wavelet Transforms

    SciTech Connect

    Szu, H.; Hsu, C.

    1996-12-31

    Human sensors systems (HSS) may be approximately described as an adaptive or self-learning version of the Wavelet Transforms (WT) that are capable to learn from several input-output associative pairs of suitable transform mother wavelets. Such an Adaptive WT (AWT) is a redundant combination of mother wavelets to either represent or classify inputs.

  7. Genetic Transformation in Citrus

    PubMed Central

    Donmez, Dicle; Simsek, Ozhan; Izgu, Tolga; Aka Kacar, Yildiz; Yalcin Mendi, Yesim

    2013-01-01

    Citrus is one of the world's important fruit crops. Recently, citrus molecular genetics and biotechnology work have been accelerated in the world. Genetic transformation, a biotechnological tool, allows the release of improved cultivars with desirable characteristics in a shorter period of time and therefore may be useful in citrus breeding programs. Citrus transformation has now been achieved in a number of laboratories by various methods. Agrobacterium tumefaciens is used mainly in citrus transformation studies. Particle bombardment, electroporation, A. rhizogenes, and a new method called RNA interference are used in citrus transformation studies in addition to A. tumefaciens. In this review, we illustrate how different gene transformation methods can be employed in different citrus species. PMID:23983635

  8. Transformable liquid-metal nanomedicine

    NASA Astrophysics Data System (ADS)

    Lu, Yue; Hu, Quanyin; Lin, Yiliang; Pacardo, Dennis B.; Wang, Chao; Sun, Wujin; Ligler, Frances S.; Dickey, Michael D.; Gu, Zhen

    2015-12-01

    To date, numerous inorganic nanocarriers have been explored for drug delivery systems (DDSs). However, the clinical application of inorganic formulations has often been hindered by their toxicity and failure to biodegrade. We describe here a transformable liquid-metal nanomedicine, based on a core-shell nanosphere composed of a liquid-phase eutectic gallium-indium core and a thiolated polymeric shell. This formulation can be simply produced through a sonication-mediated method with bioconjugation flexibility. The resulting nanoparticles loaded with doxorubicin (Dox) have an average diameter of 107 nm and demonstrate the capability to fuse and subsequently degrade under a mildly acidic condition, which facilitates release of Dox in acidic endosomes after cellular internalization. Equipped with hyaluronic acid, a tumour-targeting ligand, this formulation displays enhanced chemotherapeutic inhibition towards the xenograft tumour-bearing mice. This liquid metal-based DDS with fusible and degradable behaviour under physiological conditions provides a new strategy for engineering theranostic agents with low toxicity.

  9. Transformable liquid-metal nanomedicine.

    PubMed

    Lu, Yue; Hu, Quanyin; Lin, Yiliang; Pacardo, Dennis B; Wang, Chao; Sun, Wujin; Ligler, Frances S; Dickey, Michael D; Gu, Zhen

    2015-01-01

    To date, numerous inorganic nanocarriers have been explored for drug delivery systems (DDSs). However, the clinical application of inorganic formulations has often been hindered by their toxicity and failure to biodegrade. We describe here a transformable liquid-metal nanomedicine, based on a core-shell nanosphere composed of a liquid-phase eutectic gallium-indium core and a thiolated polymeric shell. This formulation can be simply produced through a sonication-mediated method with bioconjugation flexibility. The resulting nanoparticles loaded with doxorubicin (Dox) have an average diameter of 107?nm and demonstrate the capability to fuse and subsequently degrade under a mildly acidic condition, which facilitates release of Dox in acidic endosomes after cellular internalization. Equipped with hyaluronic acid, a tumour-targeting ligand, this formulation displays enhanced chemotherapeutic inhibition towards the xenograft tumour-bearing mice. This liquid metal-based DDS with fusible and degradable behaviour under physiological conditions provides a new strategy for engineering theranostic agents with low toxicity. PMID:26625944

  10. Transformable liquid-metal nanomedicine

    PubMed Central

    Lu, Yue; Hu, Quanyin; Lin, Yiliang; Pacardo, Dennis B.; Wang, Chao; Sun, Wujin; Ligler, Frances S.; Dickey, Michael D.; Gu, Zhen

    2015-01-01

    To date, numerous inorganic nanocarriers have been explored for drug delivery systems (DDSs). However, the clinical application of inorganic formulations has often been hindered by their toxicity and failure to biodegrade. We describe here a transformable liquid-metal nanomedicine, based on a core–shell nanosphere composed of a liquid-phase eutectic gallium-indium core and a thiolated polymeric shell. This formulation can be simply produced through a sonication-mediated method with bioconjugation flexibility. The resulting nanoparticles loaded with doxorubicin (Dox) have an average diameter of 107 nm and demonstrate the capability to fuse and subsequently degrade under a mildly acidic condition, which facilitates release of Dox in acidic endosomes after cellular internalization. Equipped with hyaluronic acid, a tumour-targeting ligand, this formulation displays enhanced chemotherapeutic inhibition towards the xenograft tumour-bearing mice. This liquid metal-based DDS with fusible and degradable behaviour under physiological conditions provides a new strategy for engineering theranostic agents with low toxicity. PMID:26625944

  11. Activation of Phosphatidylinositol 3-Kinase (PI3K) and Mitogen-activated Protein Kinase (MAPK) Signaling and the Consequent Induction of Transformation by Overexpressed 14-3-3? Protein Require Specific Amino Acids within 14-3-3? N-terminal Variable Region II*

    PubMed Central

    Radhakrishnan, Vijayababu M.; Putnam, Charles W.; Martinez, Jesse D.

    2012-01-01

    Members of the 14-3-3 superfamily regulate numerous cellular functions by binding phosphoproteins. The seven human isoforms (and the myriad of other eukaryotic 14-3-3 proteins) are highly conserved in amino acid sequence and secondary structure, yet there is abundant evidence that the various isoforms manifest disparate as well as common functions. Several of the human 14-3-3 isoforms are dysregulated in certain cancers and thus have been implicated in oncogenesis; experimentally, 14-3-3? behaves as an oncogene, whereas 14-3-3? acts as a tumor suppressor. In this study, we sought to localize these opposing phenotypes to specific regions of the two isoforms and then to individual amino acids therein. Using a bioinformatics approach, six variable regions (VRIVRVI) were identified. Using this information, two sets of constructs were created in which N-terminal portions (including either VRIIV or only VRI and VRII) of 14-3-3? and 14-3-3? were swapped; NIH3T3 cells overexpressing the four chimeric proteins were tested for transformation activity (focus formation, growth in soft agar) and activation of PI3K and MAPK signaling. We found that the specific phenotypes of 14-3-3? are associated with the N-terminal 40 amino acids (VRI and VRII); in like fashion, VRI and VRII of 14-3-3? dictated its tumor suppressor function. Using individual amino acid substitutions within the 14-3-3? VRII, we identified two residues required for and two contributing to the ?-specific phenotypes. Our observations suggest that isoform-specific phenotypes are dictated by a relatively few amino acids within variable regions. PMID:23115241

  12. Dendrimer-enabled transformation of Anaplasma phagocytophilum.

    PubMed

    Oki, Aminat T; Seidman, David; Lancina, Michael G; Mishra, Manoj K; Kannan, Rangaramanujam M; Yang, Hu; Carlyon, Jason A

    2015-01-01

    Anaplasma phagocytophilum is an obligate intracellular bacterium that causes the emerging infection, granulocytic anaplasmosis. While electroporation can transform A. phagocytophilum isolated from host cells, no method has been developed to transform it while growing inside the ApV (A. phagocytophilum-occupied vacuole). Polyamidoamine (PAMAM) dendrimers, well-defined tree-branched macromolecules used for gene therapy and nucleic acid delivery into mammalian cells, were recently shown to be effective in transforming Chlamydia spp. actively growing in host cells. We determined if we could adapt a similar system to transform A. phagocytophilum. Incubating fluorescently labeled PAMAM dendrimers with infected host cells resulted in fluorescein-positive ApVs. Incubating infected host cells or host cell-free A. phagocytophilum organisms with dendrimers complexed with pCis GFPuv-SS Himar A7 plasmid, which carries a Himar1 transposon cassette encoding GFPuv and spectinomycin/streptomycin resistance plus the Himar1 transposase itself, resulted in GFP-positive, antibiotic resistant bacteria. Yet, transformation efficiencies were low. The transformed bacterial populations could only be maintained for a few passages, likely due to random Himar1 cassette-mediated disruption of A. phagocytophilum genes required for fitness. Nonetheless, these results provide proof of principle that dendrimers can deliver exogenous DNA into A. phagocytophilum, both inside and outside of host cells. PMID:26369714

  13. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1976-01-01

    Material was presented to assist transformer designers in the transition from long-used English units to the less familiar metric equivalents. A coordination between the area product numbers ap (product of window and core cross-section areas) and current density J was developed for a given regulation and temperature rise. Straight-line relationships for Ap and Volume, Ap and surface area At and, Ap and weight were developed. These relationships can now be used as new tools to simplify and standardize the process of transformer design. They also made it possible to design transformers of small bulk and volume or to optimize efficiency.

  14. Biolistics Transformation of Wheat

    NASA Astrophysics Data System (ADS)

    Sparks, Caroline A.; Jones, Huw D.

    We present a complete, step-by-step guide to the production of transformed wheat plants using a particle bombardment device to deliver plasmid DNA into immature embryos and the regeneration of transgenic plants via somatic embryogenesis. Currently, this is the most commonly used method for transforming wheat and it offers some advantages. However, it will be interesting to see whether this position is challenged as facile methods are developed for delivering DNA by Agrobacterium tumefaciens or by the production of transformants via a germ-line process (see other chapters in this book).

  15. Acid rain information book

    SciTech Connect

    Bubenick, D.V.

    1984-01-01

    The potential consequences of widespread acid precipitation demand that this phenomenon be carefully evaluated. Review of the literature shows a rapidly growing body of knowledge, but also reveals major gaps in understanding that need to be narrowed. This document discusses major aspects of the acid rain phenomenon, points out areas of uncertainty, and summarizes current and projected research by responsible government agencies and other concerned organizations. It follows the logical progression from sources of pollutants affecting acid rain formation to the atmospheric transport and transformation of those pollutants and finally to the deposition of acid rain, the effects of that deposition, and possible mitigative measures. This information is followed by a discussion of uncertainties in the understanding of the acid rain phenomenon and a description of current and proposed research.

  16. Transformer design tradeoffs

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1977-01-01

    In space, power system transformer components are frequently the heaviest and bulkiest items in the power conversion circuit. They also have a significant effect upon the overall performance and efficiency of the system. Accordingly, the design of such transformers has an important effect on overall system weight, power-inversion efficiency, and cost. Relationships were between the parameters used by transformer designers that can be used as new tools to standardize and simplify transformer design. They can be used to optimize the design either for small size and weight or efficiency. The metric system of units, rather than the familiar English units, is used; however, material is presented to assist the reader in the transition from one system to the other.

  17. A Classical Science Transformed.

    ERIC Educational Resources Information Center

    Kovalevsky, Jean

    1979-01-01

    Describes how satellites and other tools of space technology have transformed classical geodesy into the science of space geodynamics. The establishment and the activities of the French Center for Geodynamic and Astronomical Research Studies (CERGA) are also included. (HM)

  18. Transformation of Kluyveromyces fragilis.

    PubMed

    Das, S; Kellermann, E; Hollenberg, C P

    1984-06-01

    For the transformation of the yeast species Kluyveromyces fragilis, we have constructed a vector containing a bacterial kanamycin resistance (Kmr) gene, the TRP1 gene of Saccharomyces cerevisiae, and an autonomously replicating sequence of Kluyveromyces lactis called KARS2 . By utilizing the method based on treatment by alkali cations and with the Kmr gene as the selective marker, a wild-type strain of K. fragilis was transformed to resistance against the antibiotic G418 . In the transformed cell the plasmid replicates autonomously. The same plasmid could also be used to transform S. cerevisiae trp1 mutant to Trp+. Thus, KARS2 of K. lactis enables the vector to replicate in K. fragilis, K. lactis, and S. cerevisiae, whereas ARS1 of S. cerevisiae allows autonomous replication only in S. cerevisiae. PMID:6327630

  19. Proof in Transformation Geometry

    ERIC Educational Resources Information Center

    Bell, A. W.

    1971-01-01

    The first of three articles showing how inductively-obtained results in transformation geometry may be organized into a deductive system. This article discusses two approaches to enlargement (dilatation), one using coordinates and the other using synthetic methods. (MM)

  20. Improved Transformation of Anthurium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methods to increase transformation efficiency and yields of transgenic Anthurium andraeanum Linden ex. Andr hybrids were sought while effecting gene transfer for resistance to the two most important pests, bacterial blight (Xanthomonas axonopodis pv. dieffenbachiae) and nematodes (Radopholus simili...

  1. Fourier Transform Mass Spectrometry

    PubMed Central

    Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

    2011-01-01

    This article provides an introduction to Fourier transform-based mass spectrometry. The key performance characteristics of Fourier transform-based mass spectrometry, mass accuracy and resolution, are presented in the view of how they impact the interpretation of measurements in proteomic applications. The theory and principles of operation of two types of mass analyzer, Fourier transform ion cyclotron resonance and Orbitrap, are described. Major benefits as well as limitations of Fourier transform-based mass spectrometry technology are discussed in the context of practical sample analysis, and illustrated with examples included as figures in this text and in the accompanying slide set. Comparisons highlighting the performance differences between the two mass analyzers are made where deemed useful in assisting the user with choosing the most appropriate technology for an application. Recent developments of these high-performing mass spectrometers are mentioned to provide a future outlook. PMID:21742802

  2. Mechanisms of transformation toughening

    SciTech Connect

    Olson, G.B.; Parks, D.M.

    1988-01-01

    Mechanisms of transformation toughening in ductile solids are investigated by (a) detailed observations of crack-tip processes and (b) numerical modeling with experimentally-derived constitutive relations. Two series of model ally steels have been developed for convenient study of constitutive behavior. Constitutive relations based on strain-induced transformation kinetics are being refined for these homogeneous austenitic alloys and extended to dispersed-phase systems. Using alloy composition to vary phase stability, processes of shear-instability-controlled fracture at sectioned crack tips are observed with and without transformation plasticity interactions. Quantitative constitutive relations developed for the experimental alloys are applied to (a) crack-tip and notch fields to study transformation plasticity interaction with various models of microvoid-softening-induced shear localization, and (b) inclusion particle fields to examine direct interactions with microvoid nucleation. 21 refs., 10 figs., 1 tab.

  3. Fractals and Transformations.

    ERIC Educational Resources Information Center

    Bannon, Thomas J.

    1991-01-01

    Discussed are several different transformations based on the generation of fractals including self-similar designs, the chaos game, the koch curve, and the Sierpinski Triangle. Three computer programs which illustrate these concepts are provided. (CW)

  4. Fourier transform wavemeter

    NASA Astrophysics Data System (ADS)

    Junttila, M.-L.; Sthlberg, B.; Kyr, E.; Veijola, T.; Kauppinen, J.

    1987-07-01

    We describe a scanning Michelson interferometer and utilization of fast Fourier transformation in laser wavelength determination. The Fourier transformation method is demonstrated to be particularly powerful in cw multimode (diode) laser investigations and in cw single-mode laser long-term frequency stability measurements. An uncertainty less than 10-7 can be concluded from comparisons of a two-mode polarization stabilized 543-nm He-Ne laser with an iodine stabilized 633-nm He-Ne laser.

  5. Series Transmission Line Transformer

    DOEpatents

    Buckles, Robert A.; Booth, Rex; Yen, Boris T.

    2004-06-29

    A series transmission line transformer is set forth which includes two or more of impedance matched sets of at least two transmissions lines such as shielded cables, connected in parallel at one end ans series at the other in a cascading fashion. The cables are wound about a magnetic core. The series transmission line transformer (STLT) which can provide for higher impedance ratios and bandwidths, which is scalable, and which is of simpler design and construction.

  6. Selection of Transformed Plants

    NASA Astrophysics Data System (ADS)

    Jones, Huw D.; Sparks, Caroline A.

    The low frequency and randomness of transgene integration into host cells, combined with the significant challenges of recovering whole plants from those rare events, makes the use of selectable marker genes routine in plant transformation experiments. For research applications that are unlikely to be grown in the field, strong herbicide- or antibiotic resistance is commonly used. Here we use genes conferring resistance to glufosinate herbicides as an example of a selectable marker in wheat transformation by either Agrobacterium or biolistics.

  7. Bar piezoelectric ceramic transformers.

    PubMed

    Erhart, Ji?; Pulpan, P?lpn; Rusin, Lubo

    2013-07-01

    Bar-shaped piezoelectric ceramic transformers (PTs) working in the longitudinal vibration mode (k31 mode) were studied. Two types of the transformer were designed--one with the electrode divided into two segments of different length, and one with the electrodes divided into three symmetrical segments. Parameters of studied transformers such as efficiency, transformation ratio, and input and output impedances were measured. An analytical model was developed for PT parameter calculation for both two- and three-segment PTs. Neither type of bar PT exhibited very high efficiency (maximum 72% for three-segment PT design) at a relatively high transformation ratio (it is 4 for two-segment PT and 2 for three-segment PT at the fundamental resonance mode). The optimum resistive loads were 20 and 10 k? for two- and three-segment PT designs for the fundamental resonance, respectively, and about one order of magnitude smaller for the higher overtone (i.e., 2 k? and 500 ?, respectively). The no-load transformation ratio was less than 27 (maximum for two-segment electrode PT design). The optimum input electrode aspect ratios (0.48 for three-segment PT and 0.63 for two-segment PT) were calculated numerically under no-load conditions. PMID:25004515

  8. Floral Transformation of Wheat

    NASA Astrophysics Data System (ADS)

    Agarwal, Sujata; Loar, Star; Steber, Camille; Zale, Janice

    A method is described for the floral transformation of wheat using a protocol similar to the floral dip of Arabidopsis. This method does not employ tissue culture of dissected embryos, but instead pre-anthesis spikes with clipped florets at the early, mid to late uninucleate microspore stage are dipped in Agrobacterium infiltration media harboring a vector carrying anthocyanin reporters and the NPTII selectable marker. T1 seeds are examined for color changes induced in the embryo by the anthocyanin reporters. Putatively transformed seeds are germinated and the seedlings are screened for the presence of the NPTII gene based on resistance to paromomycin spray and assayed with NPTII ELISAs. Genomic DNA of putative transformants is digested and analyzed on Southern blots for copy number to determine whether the T-DNA has integrated into the nucleus and to show the number of insertions. The non-optimized transformation efficiencies range from 0.3 to 0.6% (number of transformants/number of florets dipped) but the efficiencies are higher in terms of the number of transformants produced/number of seeds set ranging from 0.9 to 10%. Research is underway to maximize seed set and optimize the protocol by testing different Agrobacterium strains, visual reporters, vectors, and surfactants.

  9. The Transformation of Disabilities Organizations

    ERIC Educational Resources Information Center

    Schalock, Robert L.; Verdugo, Miguel-Angel

    2013-01-01

    This article summarizes the five major characteristics of the transformation era and describes how intellectual and closely related developmental disabilities organizations can apply specific transformation strategies associated with each characteristic. Collectively, the characteristics and strategies provide a framework for transformation

  10. Transformation of gram positive bacteria by sonoporation

    DOEpatents

    Yang, Yunfeng; Li, Yongchao

    2014-03-11

    The present invention provides a sonoporation-based method that can be universally applied for delivery of compounds into Gram positive bacteria. Gram positive bacteria which can be transformed by sonoporation include, for example, Bacillus, Streptococcus, Acetobacterium, and Clostridium. Compounds which can be delivered into Gram positive bacteria via sonoporation include nucleic acids (DNA or RNA), proteins, lipids, carbohydrates, viruses, small organic and inorganic molecules, and nano-particles.

  11. Folic Acid

    MedlinePLUS

    ... get enough folic acid each day? What foods contain folic acid? Can I get enough folic acid ... their doctors. Some doctors prescribe prenatal vitamins that contain higher amounts of folic acid. You are breastfeeding. ...

  12. Transformation of Phenol into Phenylalanine by a Methanogenic Consortium

    PubMed Central

    Lepine, F.; Bisaillon, J.; Milot, S.; Khalid, T. H.; Beaudet, R.; Villemur, R.

    1996-01-01

    The conversion by a methanogenic consortium of phenol into phenylalanine, with benzoic and phenylpropionic acid as intermediates, was investigated. When (sup14)C-labelled phenol was fed to the consortium, the radioactivity was mostly transferred into methane and CO(inf2), but 4% of the radioactivity was found in the water fraction after extraction of the culture medium with an organic solvent. Utilization of labelled compounds and analysis by gas chromatography coupled with mass spectrometry revealed that a fraction of the benzoic acid produced was transformed into 3-phenylpropionic acid. When fully (sup13)C-labelled acetic acid was fed to the consortium, the labels were incorporated at the 1 and 2 positions of 3-phenylpropionic acid. When deuterium-labelled 3-phenylpropionic acid was fed to the consortium, part of the phenylalanine of the biomass was labelled. These metabolic transformations are reversible, since deuterium-labelled phenylalanine generated labelled 3-phenylpropionic acid. Cinnamic acid was also transformed into 3-phenylpropionic acid. PMID:16535271

  13. Sonolysis of Short-Chain Organic Dicarboxylic Acid Solutions

    NASA Astrophysics Data System (ADS)

    Naruke, Yukio; Harada, Hisashi

    2011-07-01

    Sonolyses of C4 (carbon number 4) dicarboxylic acids (succinic acid, maleic acid, and fumaric acid) were performed in aqueous solution. They changed one into the other during sonication, affording carbon-number-conserving transformations. Maleic acid and fumaric acid were produced from saccinic acid by dehydrogenation. Furthermore, malic acid and tartaric acid were obtained by hydroxylation. The sonochemical reaction processes are discussed in terms of the time dependences of products and the addition of radical scavengers. In addition, mutual isomerization of fumaric acid and maleic acid was observed during sonication without the use of mediators.

  14. p53 domains: structure, oligomerization, and transformation.

    PubMed Central

    Wang, P; Reed, M; Wang, Y; Mayr, G; Stenger, J E; Anderson, M E; Schwedes, J F; Tegtmeyer, P

    1994-01-01

    Wild-type p53 forms tetramers and multiples of tetramers. Friedman et al. (P. N. Friedman, X. B. Chen, J. Bargonetti, and C. Prives, Proc. Natl. Acad. Sci. USA 90:3319-3323, 1993) have reported that human p53 behaves as a larger molecule during gel filtration than it does during sucrose gradient sedimentation. These differences argue that wild-type p53 has a nonglobular shape. To identify structural and oligomerization domains in p53, we have investigated the physical properties of purified segments of p53. The central, specific DNA-binding domain within murine amino acids 80 to 320 and human amino acids 83 to 323 behaves predominantly as monomers during analysis by sedimentation, gel filtration, and gel electrophoresis. This consistent behavior argues that the central region of p53 is globular in shape. Under appropriate conditions, however, this segment can form transient oligomers without apparent preference for a single oligomeric structure. This region does not enhance transformation by other oncogenes. The biological implications of transient oligomerization by this central segment, therefore, remain to be demonstrated. Like wild-type p53, the C terminus, consisting of murine amino acids 280 to 390 and human amino acids 283 to 393, behaves anomalously during gel filtration and apparently has a nonglobular shape. Within this region, murine amino acids 315 to 350 and human amino acids 323 to 355 are sufficient for assembly of stable tetramers. The finding that murine amino acids 315 to 360 enhance transformation by other oncogenes strongly supports the role of p53 tetramerization in oncogenesis. Amino acids 330 to 390 of murine p53 and amino acids 340 to 393 of human p53, which have been implicated by Sturzbecher et al. in tetramerization (H.-W. Sturzbecher, R. Brain, C. Addison, K. Rudge, M. Remm, M. Grimaldi, E. Keenan, and J. R. Jenkins, Oncogene 7:1513-1523, 1992), do not form stable tetramers under our conditions. Our findings indicate that p53 has at least two autonomous oligomerization domains: a strong tetramerization domain in its C-terminal region and a weaker oligomerization domain in the central DNA binding region of p53. Together, these domains account for the formation of tetramers and multiples of tetramers by wild-type p53. The tetramerization domain is the major determinant of the dominant negative phenotype leading to transformation by mutant p53s. Images PMID:8035799

  15. Phase Transformations and Earthquakes

    NASA Astrophysics Data System (ADS)

    Green, H. W.

    2011-12-01

    Phase transformations have been cited as responsible for, or at least involved in, "deep" earthquakes for many decades (although the concept of "deep" has varied). In 1945, PW Bridgman laid out in detail the string of events/conditions that would have to be achieved for a solid/solid transformation to lead to a faulting instability, although he expressed pessimism that the full set of requirements would be simultaneously achieved in nature. Raleigh and Paterson (1965) demonstrated faulting during dehydration of serpentine under stress and suggested dehydration embrittlement as the cause of intermediate depth earthquakes. Griggs and Baker (1969) produced a thermal runaway model of a shear zone under constant stress, culminating in melting, and proposed such a runaway as the origin of deep earthquakes. The discovery of Plate Tectonics in the late 1960s established the conditions (subduction) under which Bridgman's requirements for earthquake runaway in a polymorphic transformation could be possible in nature and Green and Burnley (1989) found that instability during the transformation of metastable olivine to spinel. Recent seismic correlation of intermediate-depth-earthquake hypocenters with predicted conditions of dehydration of antigorite serpentine and discovery of metastable olivine in 4 subduction zones, suggests strongly that dehydration embrittlement and transformation-induced faulting are the underlying mechanisms of intermediate and deep earthquakes, respectively. The results of recent high-speed friction experiments and analysis of natural fault zones suggest that it is likely that similar processes occur commonly during many shallow earthquakes after initiation by frictional failure.

  16. The patch transform.

    PubMed

    Cho, Taeg Sang; Avidan, Shai; Freeman, William T

    2010-08-01

    The patch transform represents an image as a bag of overlapping patches sampled on a regular grid. This representation allows users to manipulate images in the patch domain, which then seeds the inverse patch transform to synthesize modified images. Possible modifications include the spatial locations of patches, the size of the output image, or the pool of patches from which an image is reconstructed. When no modifications are made, the inverse patch transform reduces to solving a jigsaw puzzle. The inverse patch transform is posed as a patch assignment problem on a Markov random field (MRF), where each patch should be used only once and neighboring patches should fit to form a plausible image. We find an approximate solution to the MRF using loopy belief propagation, introducing an approximation that encourages the solution to use each patch only once. The image reconstruction algorithm scales well with the total number of patches through label pruning. In addition, structural misalignment artifacts are suppressed through a patch jittering scheme that spatially jitters the assigned patches. We demonstrate the patch transform and its effectiveness on natural images. PMID:20558879

  17. Analogue to digital transformation

    NASA Astrophysics Data System (ADS)

    1992-12-01

    ESDU 92044 examines the replacement of an analog controller element by an equivalent digital controller element while retaining for the new hybrid system performance characteristics that are acceptably similar to those of the original continuous system. The main features are described of a system containing both analog and digital elements within the same loop, and the analog-to-digital and digital-to-analog components that are then necessarily a part of the system. The frequency response characteristics of transformation are discussed, introducing the problem of aliasing whereby a digital output can be matched by continuous sine waves of different frequencies that are then indistinguishable to the digital sampler. The need to avoid aliasing is considered and the concept of a folding frequency introduced below which aliasing is impossible. Two transformation methods for designing digital filters equivalent to analog filters are discussed: the impulse invariance and bilinear transformations. They are compared by examining digital equivalents of such analogue filters as simple and compound first-order lag and lead filters, second-order lag filters and first-order notch filters. The methods are compared for two sampling rates using Bode plots illustrating the gain and phase variation with frequency. An example based on an electromechanical instrument servo illustrates the transformation of an analog lag-lead controller using the bilinear transformation.

  18. Transformation Assay for Identification of Psychrotrophic Achromobacters

    PubMed Central

    Juni, Elliot; Heym, Gloria A.

    1980-01-01

    The finding that many psychrotrophic, gram-negative, nonmotile, oxidase-positive coccobacilli (achromobacters) are competent for genetic transformation made possible the development of a transformation assay that permits recognition of genetically related strains. It has been demonstrated that 109 independently isolated achromobacters are genetically related since deoxyribonucleic acid samples from all of these organisms were able to transform a single competent auxotrophic strain to prototrophy. Genetically interacting bacteria included strains that lacked one or more of the characteristics typical for most achromobacters. An oxidase-negative mutant of one of these strains reacted positively in the transformation assay, unlike other oxidase-negative bacteria. Achromobacters were derived from fish, poultry, irradiated foods, seawater, and other sources. One strain previously classified as Micrococcus cryophilus has been shown to be related to the achromobacters. Two achromobacters had an optimum growth temperature of 35°C and behaved as typical mesophiles. The moraxellae and Acinetobacter were shown to be unrelated to the achromobacters by using the transformation assay. The ready demonstration of genetic relatedness provides a new basis for taxonomic grouping of the psychrotrophic achromobacters. Images PMID:16345673

  19. Glucuronic acid conjugates of bilirubin-IX? in normal bile compared with post-obstructive bile. Transformation of the 1-O-acylglucuronide into 2-, 3-, and 4-O-acylglucuronides

    PubMed Central

    Compernolle, Frans; Van Hees, Gustaaf P.; Blanckaert, Norbert; Heirwegh, Karel P. M.

    1978-01-01

    Structures have been determined for bilirubin-IX? conjugates in freshly collected bile of normal rats, dogs and man and in post-obstructive bile of man and rats. The originally secreted conjugate has been characterized as azopigment (I), i.e. a 1-O-acyl-?-d-glucopyranuronic acid glycoside. Conversion of the acetylated methyl ester of azopigment (I) into methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-?-d-glucopyranuronate (V) indicates the pyranose ring structure for the carbohydrate and a C-1 attachment for the bilirubin-IX? acyl group. Alternative procedures for deconjugation of azopigment (I) and its derivatives are also described. In post-obstructive bile, the 1-O-acylglucuronide is converted into 2-, 3- and 4-O-acylglucuronides via sequential intramolecular migrations of the bilirubin acyl group. The following approach was utilized. (1) The tetrapyrrole conjugates were cleaved to dipyrrolic aniline and ethyl anthranilate azopigments, and the azopigments were separated as the acids or methyl esters. (2) The isomeric methyl esters were characterized by mass spectral analysis of the acetates and silyl ethers. (3) The free glycosidic function was demonstrated by 1-oxime and 1-methoxime derivative formation. (4) The position of the dipyrrolic O-acyl group was determined for the methyl esters by protecting the free hydroxyl groups of the glucuronic acid moieties as the acetals formed with ethyl vinyl ether and by further conversion of the carbohydrates into partially methylated alditol acetates. These were analysed by using g.l.c.mass spectrometry. The relevance of the present results with regard to previous reports on disaccharidic conjugates is discussed. Details of procedures for the formation of chemical derivatives for g.l.c. and mass spectrometry have been deposited as Supplementary Publication SUP 50081 (15 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978), 169, 5. PMID:646816

  20. Fourier transform infrared spectroscopy and ab initio theory of acid-hydrogen sulfide clusters: H2S-HCl, D2S-DCl and H2S-(HCl)(2).

    PubMed

    Asselin, Pierre; Soulard, Pascale; Madebne, Bruno; Lewerenz, Marius

    2007-06-14

    The rotationally resolved Fourier transform infrared (FTIR) spectrum of the nu(s) HCl and DCl stretching bands for the hydrogen bonded complex H2S-HCl and its isotopomer D2S-DCl have been observed in a supersonic jet at 0.02 cm(-1) resolution. In the same experimental conditions, two additional bands observed without rotational structure in the HCl range of the dimer have been assigned to the cyclic trimer H2S-(HCl)(2). The multidimensional coupling picture involving the donor stretch mode nu(s) and low frequency intermolecular modes already evidenced in several medium strength hydrogen bonded complexes is beautifully confirmed by the observation of completely separated hot band progressions in the 198 K cell spectrum of both dimers. Based on our anharmonic adiabatic approach for the treatment of the coupled vibrations, absolute vibrational frequencies, diagonal and off-diagonal anharmonicities as well as rovibrational coupling constants obtained from analyses of several 2-D subspaces at MP2 and CCSD(T) level are in excellent agreement with spectroscopic results. In the case of small light complexes, the combination of elevated rotational constants and a negligible contribution of intramolecular vibrational redistribution (IVR) improve the reliability of predissociation lifetime measurements, estimated to 180 ps for H2S-HCl and above 200 ps for D2S-DCl. PMID:17538732

  1. Transformation based endorsement systems

    NASA Technical Reports Server (NTRS)

    Sudkamp, Thomas

    1988-01-01

    Evidential reasoning techniques classically represent support for a hypothesis by a numeric value or an evidential interval. The combination of support is performed by an arithmetic rule which often requires restrictions to be placed on the set of possibilities. These assumptions usually require the hypotheses to be exhausitive and mutually exclusive. Endorsement based classification systems represent support for the alternatives symbolically rather than numerically. A framework for constructing endorsement systems is presented in which transformations are defined to generate and update the knowledge base. The interaction of the knowledge base and transformations produces a non-monotonic reasoning system. Two endorsement based reasoning systems are presented to demonstrate the flexibility of the transformational approach for reasoning with ambiguous and inconsistent information.

  2. Invariants of polarization transformations.

    PubMed

    Sadjadi, Firooz A

    2007-05-20

    The use of polarization-sensitive sensors is being explored in a variety of applications. Polarization diversity has been shown to improve the performance of the automatic target detection and recognition in a significant way. However, it also brings out the problems associated with processing and storing more data and the problem of polarization distortion during transmission. We present a technique for extracting attributes that are invariant under polarization transformations. The polarimetric signatures are represented in terms of the components of the Stokes vectors. Invariant algebra is then used to extract a set of signature-related attributes that are invariant under linear transformation of the Stokes vectors. Experimental results using polarimetric infrared signatures of a number of manmade and natural objects undergoing systematic linear transformations support the invariancy of these attributes. PMID:17514238

  3. Transformation inverse design

    NASA Astrophysics Data System (ADS)

    Liu, David; Gabrielli, Lucas H.; Lipson, Michal; Johnson, Steven G.

    2013-06-01

    We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is computationally cheap because transformation optics circumvents the need to solve Maxwell's equations at each step. We apply this technique to the design of multimode waveguide bends (realized experimentally in a previous paper) and mode squeezers, in which all modes are transported equally without scattering. In addition to the optimization, a key point is the identification of the correct boundary conditions to ensure reflectionless coupling to untransformed regions while allowing maximum flexibility in the optimization. Many previous authors in transformation optics used a certain kind of quasiconformal map which overconstrained the problem by requiring that the entire boundary shape be specified a priori while at the same time underconstraining the problem by employing "slipping" boundary conditions that permit unwanted interface reflections.

  4. Transformation of cyanobacteria.

    PubMed

    Vioque, Agustín

    2007-01-01

    Cyanobacteria are a diverse and successful group of bacteria defined by their ability to carry out oxygenic photosynthesis. They occupy diverse ecological niches and are important primary producers in the oceans. Cyanobacteria are amenable to genetic manipulation. Some strains are naturally transformable. Many others have been transformed in the lab by conjugation or electroporation. The ability to transform cyanobacteria has been determinant in the development of the molecular biology of these organisms and has been the basis of many of their biotechnological applications. Cyanobacteria are the source of natural products and toxins of potential use and can be engineered to synthesize substances of biotechnological interest. Their high protein and vitamin content makes them useful as a dietary supplement. Because of their ability to occupy diverse ecological niches, they can be used to deliver to the medium substances of interest or as biosensors. PMID:18161487

  5. Generalized Chen transform: a fast transform for image compression

    NASA Astrophysics Data System (ADS)

    Allen, James D.

    1994-10-01

    The computational procedure introduced by Chen, Smith, and Fralick is in widespread use for computing the discrete cosine transform. It is popular because of its simplicity--it is a cascade of smaller (2 X 2) orthogonal transforms. We show ways to further exploit the simplicities of such procedures and introduce a new family of transform (the generalized Chen transform or GCT). One parameterization of the GCT is essentially optimal for image compression but has a lower computational cost than other transforms.

  6. Plastid transformation in soybean.

    PubMed

    Dubald, Manuel; Tissot, Ghislaine; Pelissier, Bernard

    2014-01-01

    The biotechnological potential of plastid genetic engineering has been illustrated in a limited number of higher plant species. We have developed a reproducible method to generate plastid transformants in soybean (Glycine max), a crop of major agronomic importance. The transformation vectors are delivered to embryogenic cultures by the particle gun method and selection performed using the aadA antibiotic resistance gene. Homoplasmy is established rapidly in the selected events without the need for further selection or regeneration cycles, and genes of interest can be expressed at a high level in green tissues. This is a significant step toward the commercial application of this technology. PMID:24599865

  7. Successful Transformational Radiology Leaders.

    PubMed

    Douget, Karen

    2015-01-01

    Transformational radiology leaders elevate subordinates, expand self-awareness, develop lasting relationships, strive to exceed expectations, and uphold the vision and goals of the organization. In order for radiology leaders to become more transformational in their leadership style there are four fundamental elements they must learn: idealized influence, individualized consideration, inspirational motivation, and intellectual stimulation. Leaders can utilize personality and self-assessments to learn more about themselves, identify areas of strengths and weaknesses, and learn to be more effective when leading employees. PMID:26710553

  8. Genetic Transformation of Switchgrass

    NASA Astrophysics Data System (ADS)

    Xi, Yajun; Ge, Yaxin; Wang, Zeng-Yu

    Switchgrass (Panicum virgatum L.) is a highly productive warm-season C4 species that is being developed into a dedicated biofuel crop. This chapter describes a protocol that allows the generation of transgenic switchgrass plants by Agrobacterium tumefaciens-mediated transformation. Embryogenic calluses induced from caryopses or inflorescences were used as explants for inoculation with A. tumefaciens strain EHA105. Hygromycin phosphotransferase gene (hph) was used as the selectable marker and hygromycin was used as the selection agent. Calluses resistant to hygromycin were obtained after 5-6 weeks of selection. Soil-grown switchgrass plants were regenerated about 6 months after callus induction and Agrobacterium-mediated transformation.

  9. Characterization of acid tars.

    PubMed

    Leonard, Sunday A; Stegemann, Julia A; Roy, Amitava

    2010-03-15

    Acid tars from the processing of petroleum and petrochemicals using sulfuric acid were characterized by gas chromatography/mass spectrometry (GC/MS), inductively coupled plasma/optical emission spectrometry (ICP/OES), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectrometry, and scanning electron microscopy/energy dispersive X-ray (SEM/EDX) micro-analysis. Leaching of contaminants from the acid tars in 48 h batch tests with distilled water at a liquid-to-solid ratio 10:1 was also studied. GC/MS results show that the samples contained aliphatic hydrocarbons, cyclic hydrocarbons, up to 12 of the 16 USEPA priority polycyclic aromatic hydrocarbons (PAHs), and numerous other organic groups, including organic acids (sulfonic acids, carboxylic acids and aromatic acids), phenyl, nitrile, amide, furans, thiophenes, pyrroles, and phthalates, many of which are toxic. Metals analysis shows that Pb was present in significant concentration. DSC results show different transition peaks in the studied samples, demonstrating their complexity and variability. FTIR analysis further confirmed the presence of the organic groups detected by GC/MS. The SEM/EDX micro-analysis results provided insight on the surface characteristics of the samples and show that contaminants distribution was heterogeneous. The results provide useful data on the composition, complexity, and variability of acid tars; information which hitherto have been scarce in public domain. PMID:19857924

  10. 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.

  11. Some transformations of tacrolimus, an immunosuppressive drug.

    PubMed

    Skytte, Dorthe M; Jaroszewski, Jerzy W; Johansen, Kenneth T; Hansen, Steen Honor; Hansen, Liselotte; Nielsen, Peter G; Frydenvang, Karla

    2013-02-14

    Transformations of the macrocyclic lactone tacrolimus (1), an important immunosuppressive drug produced by Streptomyces species, are described. These transformation products are primarily of interest as reference substances for drug impurity analyses. Upon action of acid (p-toluenesulfonic acid in toluene), tacrolimus is dehydrated by loss of water from the ?-hydroxyketone moiety with partial inversion of configuration at C-8, resulting in formation of 5-deoxy-?(5,6)-tacrolimus and 5-deoxy-?(5,6)-8-epitacrolimus. The structure of the latter was determined by single-crystal X-ray crystallography. The same products are formed upon action of free radicals (iodine in boiling toluene), along with formation of 8-epitacrolimus. The latter is converted by p-toluenesulfonic acid to 5-deoxy-?(5,6)-8-epitacrolimus. Treatment of tacrolimus with weak base (1,5-diazabicyclo[4.3.0]nonene) gives, in addition to 8-epitacrolimus, the open-chain acid corresponding to 5-deoxy-?(5,6)-tacrolimus, a rare non-cyclic derivative of tacrolimus. Strong base (t-butoxide) causes pronounced degradation of the molecule. Thermolysis of tacrolimus leads to ring expansion by an apparent [3,3]-sigmatropic rearrangement of the allylic ester moiety with subsequent loss of water from the ?-hydroxyketone moiety. H and C NMR spectra of the obtained compounds, complicated by the presence of amide bond rotamers and ketal moiety tautomers, were assigned by extensive use of 2D NMR techniques. PMID:23238171

  12. A FURTHER EVALUATION OF MICROCOULOMETRY FOR ATMOSPHERIC NITRIC ACID MONITORING

    EPA Science Inventory

    A coulometric instrument for measuring gaseous nitric acid is modified to improve response time characteristics and simplify operation. Possible interferences were investigated and found minimal. Comparison measurements of nitric acid by long path Fourier Transform infrared analy...

  13. Oxidative transformation of natural and synthetic phenolic mixtures by Trametes versicolor laccase.

    PubMed

    Canfora, Loredana; Iamarino, Giuseppina; Rao, Maria Antonietta; Gianfreda, Liliana

    2008-02-27

    The efficiency of Trametes versicolor laccase in the transformation of phenols (caffeic acid, catechol, hydroxytyrosol, methylcatechol, protocatechuic acid, syringic acid, m-tyrosol, 3-hydroxybenzoic acid, 3-hydroxyphenylacetic acid, 2,6-dihydroxybenzoic acid, 4-hydroxybenzaldehyde) usually present in waste water, such as that derived from an olive oil factory, was investigated. According to their response to 24 h laccase action the 11 phenolic compounds were classified in three groups: reactive (88-100% transformation), intermediate reactive (transformation lower than 50%), and recalcitrant (not transformed at all). The enzyme was able to transform the 11 substrates even when they were present in a mixture and also toward a phenolic extract from a Moroccan olive oil mill waste water (OMW) sample. The disappearance of protocatechuic, 3-hydroxyphenylacetic, and 2,6-dihydroxybenzoic acids, and 4-hydroxybenzaldehyde was enhanced whereas that of caffeic acid and m-tyrosol was depressed when the phenols were present in the mixture. A reduction of enzyme activity occurred in single and/or complex phenolic mixtures after enzymatic oxidation. No correspondence between phenol transformation and disappearance of enzymatic activity was, however, observed. The overall results suggest that laccases are effective in the transformation of simple and complex phenolic mixtures. PMID:18205305

  14. Focus On: Transforming Relationships.

    ERIC Educational Resources Information Center

    Karal, Pearl; And Others

    1985-01-01

    Karal describes the psychodynamics by which children learn to fear and distrust long-term commitments. Vaines proposes a conceptualization of the home economist as transforming actor. LeBow addresses methods of treating obese youth. Fewster and Kuhonta offer insights on communicating with Third World rural women. (SK)

  15. Fixture for winding transformers

    NASA Technical Reports Server (NTRS)

    Mclyman, M. T.

    1980-01-01

    Bench-mounted fixture assists operator in winding toroid-shaped transformer cores. Toroid is rigidly held in place as wires are looped around. Arrangement frees both hands for rapid winding and untangling of wires that occurs when core is hand held.

  16. Computerized toroidal transformer design

    NASA Technical Reports Server (NTRS)

    1970-01-01

    Computer program designs transformers which have one primary /center tap permissible/ and up to 20 untapped secondaries, and which can handle up to 500 V across any one winding. Computer determines total secondary power, core type, primary turns, secondary turns, and wire sizes for primary and secondary windings.

  17. Transformer and Meter Tester

    NASA Technical Reports Server (NTRS)

    Stoms, R. M.

    1984-01-01

    Numerically-controlled 5-axis machine tool uses transformer and meter to determine and indicate whether tool is in home position, but lacks built-in test mode to check them. Tester makes possible test, and repair of components at machine rather then replace them when operation seems suspect.

  18. Transforming American Education

    ERIC Educational Resources Information Center

    Horn, Michael B.; Mackey, Katherine

    2011-01-01

    In this article the authors accept as a given the National Education Technology Plan's vision of a transformed education system powered by technology such that learners receive personalized and engaging learning experiences, and where assessment, teaching, infrastructure, and productivity are redefined. The article analyzes this vision of a

  19. Transformer Impedance Reflection Demonstration

    ERIC Educational Resources Information Center

    Layton, William

    2014-01-01

    Questions often arise as to how a device attached to a transformer can draw power from the electrical power grid since it seems that the primary and secondary are not connected to one another. However, a closer look at how the primary and secondary are linked together magnetically and a consideration of the role of Lenz's law in this linkage…

  20. Transforming Primary Mathematics

    ERIC Educational Resources Information Center

    Askew, Mike

    2011-01-01

    What is good mathematics teaching? What is mathematics teaching good for? Who is mathematics teaching for? These are just some of the questions addressed in "Transforming Primary Mathematics", a highly timely new resource for teachers which accessibly sets out the key theories and latest research in primary maths today. Under-pinned by findings

  1. Transforming Young Lives

    ERIC Educational Resources Information Center

    Larson, Scott

    2014-01-01

    Discussions of transformational change pervade the field of business but are rare in work with young people at risk--those most in need of deep change. Instead, the nation seems preoccupied with punishing or medicating problem behavior. Some propose the alternative of "rehabilitation," but that term means "to restore to former

  2. Transformative Mixed Methods Research

    ERIC Educational Resources Information Center

    Mertens, Donna M.

    2010-01-01

    Paradigms serve as metaphysical frameworks that guide researchers in the identification and clarification of their beliefs with regard to ethics, reality, knowledge, and methodology. The transformative paradigm is explained and illustrated as a framework for researchers who place a priority on social justice and the furtherance of human rights.…

  3. Transforming Education with Technology

    ERIC Educational Resources Information Center

    Scherer, Marge

    2011-01-01

    In this EL interview, Karen Cator, the director of the Office of Educational Technology at the U.S. Department of Education, talks about ways to realize the potential of technology to transform education. She discusses what students need: their own digital devices for classroom use, the ability to use the information they access, the skills to…

  4. Imagination & Transformative Learning.

    ERIC Educational Resources Information Center

    Loughlin, Kathleen A.

    Research was conducted to gain insight into both the facilitators of consciousness-raising and the nature of this emancipatory process. Consciousness-raising was defined as a transformation of consciousness in which individuals experience critical reflection and action that develops a deepened consciousness of their situation leading them to

  5. Function Transformation without Reinforcement

    ERIC Educational Resources Information Center

    Tonneau, Francois; Arreola, Fara; Martinez, Alma Gabriela

    2006-01-01

    In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the

  6. Global Transformations and Agriculture.

    ERIC Educational Resources Information Center

    Campbell, Rex R.

    1990-01-01

    Examines worldwide political, economic, and social transformations and their impact on agriculture, focusing on biotechnology. Discusses rise of international corporations and accompanying constraints on government power. Sees trend toward increasing agribusiness role in world food and agricultural sectors. Calls for broader views and research in

  7. Transformer Impedance Reflection Demonstration

    ERIC Educational Resources Information Center

    Layton, William

    2014-01-01

    Questions often arise as to how a device attached to a transformer can draw power from the electrical power grid since it seems that the primary and secondary are not connected to one another. However, a closer look at how the primary and secondary are linked together magnetically and a consideration of the role of Lenz's law in this linkage

  8. Fourier Transform Mass Spectrometry.

    ERIC Educational Resources Information Center

    Gross, Michael L.; Rempel, Don L.

    1984-01-01

    Discusses the nature of Fourier transform mass spectrometry and its unique combination of high mass resolution, high upper mass limit, and multichannel advantage. Examines its operation, capabilities and limitations, applications (ion storage, ion manipulation, ion chemistry), and future applications and developments. (JN)

  9. Transforming Young Lives

    ERIC Educational Resources Information Center

    Larson, Scott

    2014-01-01

    Discussions of transformational change pervade the field of business but are rare in work with young people at risk--those most in need of deep change. Instead, the nation seems preoccupied with punishing or medicating problem behavior. Some propose the alternative of "rehabilitation," but that term means "to restore to former…

  10. Transformative Change Initiative

    ERIC Educational Resources Information Center

    Bragg, D. D.; Kirby, C.; Witt, M. A.; Richie, D.; Mix, S.; Feldbaum, M.; Liu, S.; Mason, M.

    2014-01-01

    The Transformative Change Initiative (TCI) is dedicated to assisting community colleges to scale up innovation in the form of guided pathways, programs of study, and evidence-based strategies to improve student outcomes and program, organization, and system performance. The impetus for TCI is the Trade Adjustment Assistance Community College and

  11. Teaching, Caring, and Transformation

    ERIC Educational Resources Information Center

    Nieto, Sonia

    2012-01-01

    Educator Bell Hooks acknowledged the fundamental truth that teaching, caring, and transformation are closely linked, that is, that true teaching must be accompanied by a deep level of care in order for learning to take place. No matter how young or old, no matter the subject matter, and no matter where teaching and learning take place--a

  12. Transforming Education with Technology

    ERIC Educational Resources Information Center

    Scherer, Marge

    2011-01-01

    In this EL interview, Karen Cator, the director of the Office of Educational Technology at the U.S. Department of Education, talks about ways to realize the potential of technology to transform education. She discusses what students need: their own digital devices for classroom use, the ability to use the information they access, the skills to

  13. Why adaptive wavelet transform?

    NASA Astrophysics Data System (ADS)

    Szu, Harold H.

    1993-08-01

    The freedom of choosing an appropriate kernel of a linear transform, which is given to us by the recent mathematical foundation of the wavelet transform, is exploited fully and is generally called the adaptive wavelet transform. However, there are several levels of adaptivity: (1) Optimum Coefficients: adjustable transform coefficients chosen with respect to a fixed mother kernel for better invariant signal representation; (2) Super-Mother: grouping different scales of daughter wavelets of same or different eother wavelets at different shift locations into a new family called a superposition mother kernel for better speech signal classification; (3) Variational Calculus to determine ab initio a constraint optimization mother for a specific task. The tradeoff between the mathematical rigor of the complete orthonormality and the speed of order (N) with the adaptive flexibility is finally up to the users' decisions to get their jobs done with the desirable properties. Then, to illustrate (1), a new invariant optoelectronic architecture of a wedge-shape filter in the WT domain is given for a scale-invariant signal classification by neural networks.

  14. Transforming Data into Knowledge

    ERIC Educational Resources Information Center

    Mills, Lane

    2006-01-01

    School systems can be data rich and information poor if they do not understand and manage their data effectively. The task for school leaders is to put existing data into a format that lends itself to answering questions and improving outcomes for the students. Common barriers to transforming data into knowledge in education settings often include

  15. Is Distance Learning Transformational?

    ERIC Educational Resources Information Center

    Hoskins, Barbara J.

    2013-01-01

    Is distance learning transformational? The author heard this question posed to a panel of faculty members during Distance Education Week activities. After reflecting upon her own students' reaction to her syllabus, her answer to the question changed from an initial, enthusiastic "yes" to a reflective "maybe," given the most favorable environment.

  16. Transformative Mixed Methods Research

    ERIC Educational Resources Information Center

    Mertens, Donna M.

    2010-01-01

    Paradigms serve as metaphysical frameworks that guide researchers in the identification and clarification of their beliefs with regard to ethics, reality, knowledge, and methodology. The transformative paradigm is explained and illustrated as a framework for researchers who place a priority on social justice and the furtherance of human rights.

  17. Phosphoric Acid-Mediated Synthesis of Vinyl Sulfones through Decarboxylative Coupling Reactions of Sodium Sulfinates with Phenylpropiolic Acids.

    PubMed

    Rong, Guangwei; Mao, Jincheng; Yan, Hong; Zheng, Yang; Zhang, Guoqi

    2015-08-01

    A novel phosphoric acid -mediated synthesis of vinyl sulfones through decarboxylative coupling reactions of sodium sulfinates with phenylpropiolic acids is described. This transformation is efficient and environmentally friendly. PMID:26207418

  18. Rainbow Fourier Transform

    NASA Technical Reports Server (NTRS)

    Alexandrov, Mikhail D.; Cairns, Brian; Mishchenko, Michael I.

    2012-01-01

    We present a novel technique for remote sensing of cloud droplet size distributions. Polarized reflectances in the scattering angle range between 135deg and 165deg exhibit a sharply defined rainbow structure, the shape of which is determined mostly by single scattering properties of cloud particles, and therefore, can be modeled using the Mie theory. Fitting the observed rainbow with such a model (computed for a parameterized family of particle size distributions) has been used for cloud droplet size retrievals. We discovered that the relationship between the rainbow structures and the corresponding particle size distributions is deeper than it had been commonly understood. In fact, the Mie theory-derived polarized reflectance as a function of reduced scattering angle (in the rainbow angular range) and the (monodisperse) particle radius appears to be a proxy to a kernel of an integral transform (similar to the sine Fourier transform on the positive semi-axis). This approach, called the rainbow Fourier transform (RFT), allows us to accurately retrieve the shape of the droplet size distribution by the application of the corresponding inverse transform to the observed polarized rainbow. While the basis functions of the proxy-transform are not exactly orthogonal in the finite angular range, this procedure needs to be complemented by a simple regression technique, which removes the retrieval artifacts. This non-parametric approach does not require any a priori knowledge of the droplet size distribution functional shape and is computationally fast (no look-up tables, no fitting, computations are the same as for the forward modeling).

  19. Reversal of the temperature-shift-induced growth restriction of a temperature-sensitive simian virus 40 T-antigen-transformed human fibroblast cell line by treatment with retinoic acid.

    PubMed Central

    Tsao, Y P; Li, S F; Kuo, S W; Liu, J C; Chen, S L

    1996-01-01

    We previously established a human fibroblast cell line, HFL 6-2, that contains a temperature sensitive simian virus 40 (SV40) T antigen, permitting cell growth at 35 degrees C but restricting growth at 39 degrees C. p21 (Waf1/Cip1) was significantly induced by temperature shifts in HFL 6-2 cells. Here we show that all-trans-retinoic acid (RA) treatment prevented the growth restriction of HFL 6-2 cells at 39 degrees C. In the presence of RA, HFL 6-2 cells proliferated into sizeable colonies even at 39 degrees C. [3H]Thymidine incorporation and flow cytometry analysis revealed that cells exposed to RA maintained DNA synthesis at 39 degrees C. Prevention of growth restriction by RA was correlated with a lack of induction of p21 at the transcription level. These observations suggest that RA may prevent the senescence process by repressing p21 gene expression, and perturb the growth regulation of somatic cells. PMID:8760353

  20. (Hadamard transform imaging)

    SciTech Connect

    Not Available

    1990-01-01

    This report describes the design of, and image reconstruction capacity of a Hadamard Raman Microscopic imager. Microscopy of benzoic acid and graphite electrodes, as well as electrophoretic blotting, are described. (CBS)

  1. OVOC Emissions and Atmospheric Transformations.

    NASA Astrophysics Data System (ADS)

    Yokelson, R. J.; Christian, T. J.; Bertschi, I. T.; Ward, D. E.; Field, R. J.; Hobbs, P. V.; Goode, J.; Mason, S.; Susott, R.; Babbitt, R.; Hao, W. M.

    2002-12-01

    We quantified the main emissions from a few vegetation samples and many biomass fires using ground-based, open-path FTIR and airborne, closed-cell FTIR. The two instruments have been rigorously compared to each other and to PTR-MS and canister sampling. OVOC are major emissions from plants. OVOC account for about 70 percent of NMOC from savanna fires (the largest type of biomass burning) and 70-80 percent of NMOC from production and use of domestic biofuels (the second largest type of biomass burning). A table of average biofuel emissions is presented. Data from laboratory and free-burning fires, obtained from Alaska to South Africa, is used to develop equations that predict OVOC emissions from a wide variety of global fires. The impact of OVOC on smoke plume chemistry and the post-emission transformations of OVOC were investigated with two models. Addition of HCHO alone to the simple chemistry used in some global models dramatically reduces NOx lifetime and speeds up O3 formation rates in plumes. A detailed model verifies these effects and shows that OVOC profoundly affect formation of HOx, peroxide, and nitrogen reservoir species. The modeled photochemical transformations of OVOC are diverse, but some key pathways are unknown. We observed rapid production of both O3 and additional OVOC and OH of 1.7E7 in smoke plumes in Alaska and Africa; all reasonably consistent with model predictions. In addition, we found that cloud processing caused large post-emission changes in smoke trace gases including removal of nearly all methanol, a decrease in acetic acid, and a large increase in HCHO. These observations suggest that OVOC could react in cloud droplets and lead to production of modified aerosol. In addition, transport of OVOC by deep convection may be associated with large effects not explained by solubility alone.

  2. Acid Rain

    MedlinePLUS

    ... damaging to lakes, streams, and forests and the plants and animals that live in these ecosystems. This Web site provides information about the following: What causes acid rain The effects of acid rain How we measure acid rain ...

  3. 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 ...

  4. 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 ...

  5. 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 ...

  6. Nature and transformation of dissolved organic matter in treatment wetlands.

    PubMed

    Barber, L B; Leenheer, J A; Noyes, T I; Stiles, E A

    2001-12-15

    This investigation into the occurrence, character, and transformation of dissolved organic matter (DOM) in treatment wetlands in the western United States shows that (i) the nature of DOM in the source water has a major influence on transformations that occur during treatment, (ii) the climate factors have a secondary effect on transformations, (iii) the wetlands receiving treated wastewater can produce a net increase in DOM, and (iv) the hierarchical analytical approach used in this study can measure the subtle DOM transformations that occur. As wastewater treatment plant effluent passes through treatment wetlands, the DOM undergoes transformation to become more aromatic and oxygenated. Autochthonous sources are contributed to the DOM, the nature of which is governed by the developmental stage of the wetland system as well as vegetation patterns. Concentrations of specific wastewater-derived organic contaminants such as linear alkylbenzene sulfonate, caffeine, and ethylenediaminetetraacetic acid were significantly attenuated by wetland treatment and were not contributed by internal loading. PMID:11775156

  7. Application of Fourier transform spectroscopy to air pollution problems

    NASA Astrophysics Data System (ADS)

    Shaw, J. H.; Calvert, J. G.

    1980-11-01

    The nature of information that can be retrieved from spectra obtained with Fourier transform spectroscopy is discussed. Nonlinear, least squares analysis of spectra is capable of retrieving information that is beyond the reach of conventional methods and has improved precision and accuracy. Fourier transform infrared spectroscopy was used to study quantitatively the kinetics and mechanisms of several chemical reactions that are of interest to atmospheric chemists and are important in the development of air pollution control strategies. The systems studied include the metastable, reactive, gaseous species, peroxynitric acid, hypochlorous acid, and dimethylnitrosamine.

  8. Conjugated Fatty Acid Synthesis

    PubMed Central

    Rawat, Richa; Yu, Xiao-Hong; Sweet, Marie; Shanklin, John

    2012-01-01

    Conjugated linolenic acids (CLNs), 18:3 ?9,11,13, lack the methylene groups found between the double bonds of linolenic acid (18:3 ?9,12,15). CLNs are produced by conjugase enzymes that are homologs of the oleate desaturases FAD2. The goal of this study was to map the domain(s) within the Momordica charantia conjugase (FADX) responsible for CLN formation. To achieve this, a series of Momordica FADX-Arabidopsis FAD2 chimeras were expressed in the Arabidopsis fad3fae1 mutant, and the transformed seeds were analyzed for the accumulation of CLN. These experiments identified helix 2 and the first histidine box as a determinant of conjugase product partitioning into punicic acid (18:3 ?9cis,11trans,13cis) or ?-eleostearic acid (18:3 ?9cis,11trans,13trans). This was confirmed by analysis of a FADX mutant containing six substitutions in which the sequence of helix 2 and first histidine box was converted to that of FAD2. Each of the six FAD2 substitutions was individually converted back to the FADX equivalent identifying residues 111 and 115, adjacent to the first histidine box, as key determinants of conjugase product partitioning. Additionally, expression of FADX G111V and FADX G111V/D115E resulted in an approximate doubling of eleostearic acid accumulation to 20.4% and 21.2%, respectively, compared with 9.9% upon expression of the native Momordica FADX. Like the Momordica conjugase, FADX G111V and FADX D115E produced predominantly ?-eleostearic acid and little punicic acid, but the FADX G111V/D115E double mutant produced approximately equal amounts of ?-eleostearic acid and its isomer, punicic acid, implicating an interactive effect of residues 111 and 115 in punicic acid formation. PMID:22451660

  9. High voltage isolation transformer

    NASA Technical Reports Server (NTRS)

    Clatterbuck, C. H.; Ruitberg, A. P. (Inventor)

    1985-01-01

    A high voltage isolation transformer is provided with primary and secondary coils separated by discrete electrostatic shields from the surfaces of insulating spools on which the coils are wound. The electrostatic shields are formed by coatings of a compound with a low electrical conductivity which completely encase the coils and adhere to the surfaces of the insulating spools adjacent to the coils. Coatings of the compound also line axial bores of the spools, thereby forming electrostatic shields separating the spools from legs of a ferromagnetic core extending through the bores. The transformer is able to isolate a high constant potential applied to one of its coils, without the occurrence of sparking or corona, by coupling the coatings, lining the axial bores to the ferromagnetic core and by coupling one terminal of each coil to the respective coating encasing the coil.

  10. Reduction/Transformation Operators

    Energy Science and Technology Software Center (ESTSC)

    2006-09-01

    RTOp (reduction/transformation operators) is a collection of C++ software that provides the basic mechanism for implementinig vector operations in a flexible and efficient manner. This is the main interface utilized by Thyra to allow for the specification of specific vector reduction and/or transformation operations. The RTOp package contains three different types of software. (a) a small number of interoperability interfaces. (b) support software including code for the parallel SPMD mode based on only Teuchos::Comm(and notmore »MPl directly(, and (c) a library of pre-implemented RTOp subclasses for everything from simple AXPYs and norms, to more specialized vector operations. RTOp allows an algorithm developer to implement their own RTOp subclasses in a way that is independent from any specific serial, parallel, out-of-core or other type of vector implementation. RTOp is a required package by Thyra and MOOCHO. (c)« less

  11. Transformation of Bacillus subtilis.

    PubMed

    Zhang, Xiao-Zhou; You, Chun; Zhang, Yi-Heng Percival

    2014-01-01

    Bacillus subtilis has tremendous applications in both academic research and industrial production. However, molecular cloning and transformation of B. subtilis are not as easy as those of Escherichia coli. Here we developed a simple protocol based on super-competent cells prepared from the recombinant B. subtilis strain SCK6 and multimeric plasmids generated by prolonged overlap extension-PCR. Super-competent B. subtilis SCK6 cells were prepared by overexpression of the competence master regulator ComK that was induced by adding xylose. This new protocol is simple (e.g., restriction enzyme, phosphatase, and ligase free), fast, and highly efficient (i.e., ~10(7) or ~10(4) transformants per ?g of multimeric plasmid or ligated plasmid DNA, respectively). Shuttle vectors for E. coli-B. subtilis are not required. PMID:24838881

  12. Transforming the optical landscape

    NASA Astrophysics Data System (ADS)

    Pendry, J. B.; Luo, Yu; Zhao, Rongkuo

    2015-05-01

    Electromagnetism provides us with some of the most powerful tools in science, encompassing lasers, optical microscopes, magnetic resonance imaging scanners, radar, and a host of other techniques. To understand and develop the technology requires more than a set of formal equations. Scientists and engineers have to form a vivid picture that fires their imaginations and enables intuition to play a full role in the process of invention. It is to this end that transformation optics has been developed, exploiting Faraday’s picture of electric and magnetic fields as lines of force, which can be manipulated by the electrical permittivity and magnetic permeability of surrounding materials. Transformation optics says what has to be done to place the lines of force where we want them to be.

  13. A DC Transformer

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C.; Ihlefeld, Curtis M.; Starr, Stanley O.

    2013-01-01

    A component level dc transformer is described in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both de devices, such that the output voltage of a de power supply can be stepped up (or down) with a corresponding step down (or up) in current. The basic theory for this device is developed, performance predictions are made, and the results from a small prototype are presented. Based on demonstrated technology in the literature, this de transformer should be scalable to low megawatt levels, but it is more suited to high current than high voltage applications. Significant development would be required before it could achieve the kilovolt levels needed for de power transmission.

  14. Transforming the optical landscape.

    PubMed

    Pendry, J B; Luo, Yu; Zhao, Rongkuo

    2015-05-01

    Electromagnetism provides us with some of the most powerful tools in science, encompassing lasers, optical microscopes, magnetic resonance imaging scanners, radar, and a host of other techniques. To understand and develop the technology requires more than a set of formal equations. Scientists and engineers have to form a vivid picture that fires their imaginations and enables intuition to play a full role in the process of invention. It is to this end that transformation optics has been developed, exploiting Faraday's picture of electric and magnetic fields as lines of force, which can be manipulated by the electrical permittivity and magnetic permeability of surrounding materials. Transformation optics says what has to be done to place the lines of force where we want them to be. PMID:25931549

  15. Laminated piezoelectric transformer

    NASA Technical Reports Server (NTRS)

    Vazquez Carazo, Alfredo (Inventor)

    2006-01-01

    A laminated piezoelectric transformer is provided using the longitudinal vibration modes for step-up voltage conversion applications. The input portions are polarized to deform in a longitudinal plane and are bonded to an output portion. The deformation of the input portions is mechanically coupled to the output portion, which deforms in the same longitudinal direction relative to the input portion. The output portion is polarized in the thickness direction relative its electrodes, and piezoelectrically generates a stepped-up output voltage.

  16. Transforming revenue management.

    PubMed

    Silveria, Richard; Alliegro, Debra; Nudd, Steven

    2008-11-01

    Healthcare organizations that want to undertake a patient administrative/revenue management transformation should: Define the vision with underlying business objectives and key performance measures. Strategically partner with key vendors for business process development and technology design. Create a program organization and governance infrastructure. Develop a corporate design model that defines the standards for operationalizing the vision. Execute the vision through technology deployment and corporate design model implementation. PMID:18990839

  17. Microbial transformation of benzosampangine.

    PubMed

    Orabi, K Y; Clark, A M; Hufford, C D

    2000-03-01

    Microbial transformation studies of the synthetic antifungal alkaloid benzosampangine (1) have revealed that 1 is metabolized by a number of microorganisms. Using a standard two-stage fermentation technique Absidia glauca (ATCC 22752), Cunninghamella blakesleeana (ATCC 8688a), Cunninghamella species (NRRL 5695), Fusarium solani f. sp. cucurbitae (CSIH #C-5), and Rhizopogon species (ATCC 36060) each produced a beta-glucopyranose conjugate of benzosampangine (2). The identity of 2 was established on the basis of spectroscopic data. PMID:10757729

  18. Bacterial transformation of terpenoids

    NASA Astrophysics Data System (ADS)

    Grishko, V. V.; Nogovitsina, Y. M.; Ivshina, I. B.

    2014-04-01

    Data on the bacterial transformation of terpenoids published in the literature in the past decade are analyzed. Possible pathways for chemo-, regio- and stereoselective modifications of terpenoids are discussed. Considerable attention is given to new technological approaches to the synthesis of terpenoid derivatives suitable for the use in the perfume and food industry and promising as drugs and chiral intermediates for fine organic synthesis. The bibliography includes 246 references.

  19. Coded holography for Walsh transform and Haar transform

    NASA Astrophysics Data System (ADS)

    Ben Uri, Joseph

    1993-03-01

    Digital transforms, such as Walsh or Haar transforms for example, are often used to improve the quality of the picture and obtain a better resolution. The mathematical computer procedure of the transform operation can, however, be lengthy and complicated. We suggest use of coded holography with a mask representing the Walsh or Haar transform as a reference beam. Details of the set up and the construction of the mask are discussed and the results are shown.

  20. 60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER WAS USED TO SENSE HIGH CURRENT BEING GENERATED ON GENERATOR NUMBER 3 AND REDUCE IT TO A LOWER, EXACT ANALOG VALUE THAT COULD BE SAFELY HANDLED AND MONITORED WITH THE CONTROL CIRCUITRY. THE CURRENT TRANSFORMER IS LOCATED IN THE CENTER OF THE PHOTOGRAPH. THE CONNECTING BUS ABOVE THE TRANSFORMER WAS REMOVED FOR SALVAGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

  1. Mineral oxide transformation of antimicrobial contaminants

    NASA Astrophysics Data System (ADS)

    Guo, B.; Kendall, T. A.

    2008-12-01

    The quality of our water supply is dependent on the organic-mineral interface. Organics contain reactive groups that dissolve minerals, and release surface associated contaminants into aquifers and reservoirs. Conversely, minerals may transform organic pollutants, including antimicrobial drugs that are potentially deleterious to aquatic ecosystems or human health. Under aqueous conditions typical of soils and natural waters, the antibiotic agent sulfamethoxazole (SMX) is transformed in the presence of pyrolusite, presumably on the MnO2 surface. At least 50 percent loss of SMX was observed after 269 h, in both acidic and basic solutions (pH 3-9). Nearly 100 percent loss is recorded at pH 3 and 66 percent loss was recorded at circumneutral pH. Initial mass spectrometry of the reaction products suggests an oxidative pathway where hydroxylation and oxidation occurs at the aniline moiety and isoxazolamine ring of SMX. Concomitant increases in aqueous manganese concentrations suggest reductive transformation of the mineral surface. Ongoing electric force spectroscopy and force microscopy experiments probe potential mineral surface alteration associated with the SMX-MnO2 reaction. Coupling bulk aqueous observations and mass spectrometry with molecular-scale force microscopy should further elucidate sulfonamide reactivity as influenced by mineral surface chemistry and topography. Moreover, the observed transformation suggests manganese oxides likely play an important role in the fate of SMX in the environment.

  2. 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.

  3. 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

  4. Transformation of xanthohumol by Aspergillus ochraceus.

    PubMed

    Tronina, Tomasz; Bartma?ska, Agnieszka; Pop?o?ski, Jaros?aw; Huszcza, Ewa

    2014-01-01

    Microbial transformation of xanthohumol isolated from agro-residue (spent hops), by Aspergillus ochraceus was investigated. A new aurone, (Z)-2?-(2?-hydroxyisopropyl)-dihydrofurano[4?,5?:6,7]-3',4'-dihydroxy-4-methoxyaurone, was obtained as a main transformation product. Three minor metabolites were identified as 2?-(2?-hydroxyisopropyl)-dihydrofurano[4?,5?:3',4']-2',4-dihydroxy-6'-methoxychalcone, (2S,2?S)-2?-(2?-hydroxyisopropyl)-dihydrofurano[4?,5?:7,8]-4'-hydroxy-5-methoxyflavanone and (2S,2?R)-2?-(2?-hydroxyisopropyl)-dihydrofurano[4?,5?:7,8]-4'-hydroxy-5-methoxyflavanone. Their structures were elucidated on the basis of spectroscopic evidences. The antioxidant properties of xanthohumol and its metabolites were investigated using the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The major biotransformation product, was 8.6-fold stronger antioxidant than xanthohumol and 2.3-fold than ascorbic acid. PMID:23463662

  5. Chloroplast transformation for engineering of photosynthesis.

    PubMed

    Hanson, Maureen R; Gray, Benjamin N; Ahner, Beth A

    2013-01-01

    Many efforts are underway to engineer improvements in photosynthesis to meet the challenges of increasing demands for food and fuel in rapidly changing environmental conditions. Various transgenes have been introduced into either the nuclear or plastid genomes in attempts to increase photosynthetic efficiency. We examine the current knowledge of the critical features that affect levels of expression of plastid transgenes and protein accumulation in transplastomic plants, such as promoters, 5' and 3' untranslated regions, RNA-processing sites, translation signals and amino acid sequences that affect protein turnover. We review the prior attempts to manipulate the properties of ribulose-1,5-bisphosphate carboxylase oxygenase (Rubisco) through plastid transformation. We illustrate how plastid operons could be created for expression of the multiple genes needed to introduce new pathways or enzymes to enhance photosynthetic rates or reduce photorespiration. We describe here the past accomplishments and future prospects for manipulating plant enzymes and pathways to enhance carbon assimilation through plastid transformation. PMID:23162121

  6. Transformational Leadership, Integrity, and Power

    ERIC Educational Resources Information Center

    Harrison, Laura M.

    2011-01-01

    Transformational leadership enjoys widespread appeal among student affairs professionals. National Association of Student Personnel Administrators (NASPA) and American College Personnel Association (ACPA) conferences frequently feature speakers who promote transformational leadership's two primary tenets: (1) change is the central purpose of

  7. Transformational Leadership, Integrity, and Power

    ERIC Educational Resources Information Center

    Harrison, Laura M.

    2011-01-01

    Transformational leadership enjoys widespread appeal among student affairs professionals. National Association of Student Personnel Administrators (NASPA) and American College Personnel Association (ACPA) conferences frequently feature speakers who promote transformational leadership's two primary tenets: (1) change is the central purpose of…

  8. RECENT ADVANCES IN BARLEY TRANSFORMATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Barley, an important member of the cereals, has been successfully transformed through various methods such as particle bombardment, Agrobacterium-tumefaciens, DNA uptake, and electroporation. Initially, the transformation in barley concentrated on developing protocols using marker genes such as gus,...

  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. Thin-Film Power Transformers

    NASA Technical Reports Server (NTRS)

    Katti, Romney R.

    1995-01-01

    Transformer core made of thin layers of insulating material interspersed with thin layers of ferromagnetic material. Flux-linking conductors made of thinner nonferromagnetic-conductor/insulator multilayers wrapped around core. Transformers have geometric features finer than those of transformers made in customary way by machining and mechanical pressing. In addition, some thin-film materials exhibit magnetic-flux-carrying capabilities superior to those of customary bulk transformer materials. Suitable for low-cost, high-yield mass production.

  11. Spectrum transformation for divergent iterations

    NASA Technical Reports Server (NTRS)

    Gupta, Murli M.

    1991-01-01

    Certain spectrum transformation techniques are described that can be used to transform a diverging iteration into a converging one. Two techniques are considered called spectrum scaling and spectrum enveloping and how to obtain the optimum values of the transformation parameters is discussed. Numerical examples are given to show how this technique can be used to transform diverging iterations into converging ones; this technique can also be used to accelerate the convergence of otherwise convergent iterations.

  12. Nonlinear transient simulation of transformers

    SciTech Connect

    Pierrat, L.; Tran-Quoc, T.; Montmeat, A.

    1995-12-31

    In this paper, a nonlinear model of transformer which takes into account both the saturation and the hysteresis is proposed. In order to simulate transient phenomena in transformers, a system of equations is presented. The digital simulation of the energization and de-energization of a three-phase distribution transformer is studied. Ferroresonant phenomena in iron core transformers supplied through capacitive links are presented. Finally, the influence of MOV arresters on overvoltage reduction is investigated.

  13. Quality as Transformation: Educational Metamorphosis

    ERIC Educational Resources Information Center

    Cheng, Ming

    2014-01-01

    The notion of "quality as transformation" has been widely used in the higher education sector. However, both quality and transformation are elusive terms. There is little research exploring how quality could be equated to transformation in the learning process. This paper will provide an insight into the relationship between quality and

  14. Enhancing Understanding of Transformation Matrices

    ERIC Educational Resources Information Center

    Dick, Jonathan; Childrey, Maria

    2012-01-01

    With the Common Core State Standards' emphasis on transformations, teachers need a variety of approaches to increase student understanding. Teaching matrix transformations by focusing on row vectors gives students tools to create matrices to perform transformations. This empowerment opens many doors: Students are able to create the matrices for

  15. Enhancing Understanding of Transformation Matrices

    ERIC Educational Resources Information Center

    Dick, Jonathan; Childrey, Maria

    2012-01-01

    With the Common Core State Standards' emphasis on transformations, teachers need a variety of approaches to increase student understanding. Teaching matrix transformations by focusing on row vectors gives students tools to create matrices to perform transformations. This empowerment opens many doors: Students are able to create the matrices for…

  16. Teacher Transformation: Transcending Hegemonic Roots

    ERIC Educational Resources Information Center

    Peters, Gregory

    2012-01-01

    In this dissertation study, I build from the research on transformative teaching (transformative for students), liberating theories (Liberating, Liberation and Liberating Theories) as well as literature about transformation, reflection and discourse to make the case that our historic and continuously inequitable results for students based on…

  17. Canonical Transformations of Kepler Trajectories

    ERIC Educational Resources Information Center

    Mostowski, Jan

    2010-01-01

    In this paper, canonical transformations generated by constants of motion in the case of the Kepler problem are discussed. It is shown that canonical transformations generated by angular momentum are rotations of the trajectory. Particular attention is paid to canonical transformations generated by the Runge-Lenz vector. It is shown that these…

  18. Canonical Transformations of Kepler Trajectories

    ERIC Educational Resources Information Center

    Mostowski, Jan

    2010-01-01

    In this paper, canonical transformations generated by constants of motion in the case of the Kepler problem are discussed. It is shown that canonical transformations generated by angular momentum are rotations of the trajectory. Particular attention is paid to canonical transformations generated by the Runge-Lenz vector. It is shown that these

  19. Teacher Transformation: Transcending Hegemonic Roots

    ERIC Educational Resources Information Center

    Peters, Gregory

    2012-01-01

    In this dissertation study, I build from the research on transformative teaching (transformative for students), liberating theories (Liberating, Liberation and Liberating Theories) as well as literature about transformation, reflection and discourse to make the case that our historic and continuously inequitable results for students based on

  20. Quality as Transformation: Educational Metamorphosis

    ERIC Educational Resources Information Center

    Cheng, Ming

    2014-01-01

    The notion of "quality as transformation" has been widely used in the higher education sector. However, both quality and transformation are elusive terms. There is little research exploring how quality could be equated to transformation in the learning process. This paper will provide an insight into the relationship between quality and…

  1. Inversion of the circular averages transform using the Funk transform

    NASA Astrophysics Data System (ADS)

    Evren Yarman, Can; Yaz?c?, Birsen

    2011-06-01

    The integral of a function defined on the half-plane along the semi-circles centered on the boundary of the half-plane is known as the circular averages transform. Circular averages transform arises in many tomographic image reconstruction problems. In particular, in synthetic aperture radar (SAR) when the transmitting and receiving antennas are colocated, the received signal is modeled as the integral of the ground reflectivity function of the illuminated scene over the intersection of spheres centered at the antenna location and the surface topography. When the surface topography is flat the received signal becomes the circular averages transform of the ground reflectivity function. Thus, SAR image formation requires inversion of the circular averages transform. Apart from SAR, circular averages transform also arises in thermo-acoustic tomography and sonar inverse problems. In this paper, we present a new inversion method for the circular averages transform using the Funk transform. For a function defined on the unit sphere, its Funk transform is given by the integrals of the function along the great circles. We used hyperbolic geometry to establish a diffeomorphism between the circular averages transform, hyperbolic x-ray and Funk transforms. The method is exact and numerically efficient when fast Fourier transforms over the sphere are used. We present numerical simulations to demonstrate the performance of the inversion method. Dedicated to Dennis Healy, a friend of Applied Mathematics and Engineering.

  2. Comparison of Soybean Transformation Efficiency and Plant Factors Affecting Transformation during the Agrobacterium Infection Process.

    PubMed

    Jia, Yuying; Yao, Xingdong; Zhao, Mingzhe; Zhao, Qiang; Du, Yanli; Yu, Cuimei; Xie, Futi

    2015-01-01

    The susceptibility of soybean genotype to Agrobacterium infection is a key factor for the high level of genetic transformation efficiency. The objective of this study is to evaluate the plant factors related to transformation in cotyledonary nodes during the Agrobacterium infection process. This study selected three genotypes (Williams 82, Shennong 9 and Bert) with high transformation efficiency, which presented better susceptibility to Agrobacterium infection, and three low transformation efficiency genotypes (General, Liaodou 16 and Kottman), which showed a relatively weak susceptibility. Gibberellin (GA) levels and soybean GA20ox2 and CYP707A2 transcripts of high-efficiency genotypes increased and were higher than those of low-efficiency genotypes; however, the opposite performance was shown in abscisic acid (ABA). Higher zeatin riboside (ZR) content and DNA quantity, and relatively higher expression of soybean IPT5, CYCD3 and CYCA3 were obtained in high-efficiency genotypes. High-efficiency genotypes had low methyl jasmonate (MeJA) content, polyphenol oxidase (PPO) and peroxidase (POD) activity, and relatively lower expression of soybean OPR3, PPO1 and PRX71. GA and ZR were positive plant factors for Agrobacterium-mediated soybean transformation by facilitating germination and growth, and increasing the number of cells in DNA synthesis cycle, respectively; MeJA, PPO, POD and ABA were negative plant factors by inducing defence reactions and repressing germination and growth, respectively. PMID:26262617

  3. Comparison of Soybean Transformation Efficiency and Plant Factors Affecting Transformation during the Agrobacterium Infection Process

    PubMed Central

    Jia, Yuying; Yao, Xingdong; Zhao, Mingzhe; Zhao, Qiang; Du, Yanli; Yu, Cuimei; Xie, Futi

    2015-01-01

    The susceptibility of soybean genotype to Agrobacterium infection is a key factor for the high level of genetic transformation efficiency. The objective of this study is to evaluate the plant factors related to transformation in cotyledonary nodes during the Agrobacterium infection process. This study selected three genotypes (Williams 82, Shennong 9 and Bert) with high transformation efficiency, which presented better susceptibility to Agrobacterium infection, and three low transformation efficiency genotypes (General, Liaodou 16 and Kottman), which showed a relatively weak susceptibility. Gibberellin (GA) levels and soybean GA20ox2 and CYP707A2 transcripts of high-efficiency genotypes increased and were higher than those of low-efficiency genotypes; however, the opposite performance was shown in abscisic acid (ABA). Higher zeatin riboside (ZR) content and DNA quantity, and relatively higher expression of soybean IPT5, CYCD3 and CYCA3 were obtained in high-efficiency genotypes. High-efficiency genotypes had low methyl jasmonate (MeJA) content, polyphenol oxidase (PPO) and peroxidase (POD) activity, and relatively lower expression of soybean OPR3, PPO1 and PRX71. GA and ZR were positive plant factors for Agrobacterium-mediated soybean transformation by facilitating germination and growth, and increasing the number of cells in DNA synthesis cycle, respectively; MeJA, PPO, POD and ABA were negative plant factors by inducing defence reactions and repressing germination and growth, respectively. PMID:26262617

  4. Transformation of Anaplasma marginale

    PubMed Central

    Felsheim, Roderick F.; Chávez, Adela S. Oliva; Palmer, Guy H.; Crosby, Liliana; Barbet, Anthony F.; Kurtti, Timothy J.; Munderloh, Ulrike G.

    2010-01-01

    The tick-borne pathogen, Anaplasma marginale, has a complex life cycle involving ruminants and ixodid ticks. It causes bovine anaplasmosis, a disease with significant economic impact on cattle farming worldwide. The obligate intracellular growth requirement of the bacteria poses a challenging obstacle to their genetic manipulation, a problem shared with other prokaryotes in the genera Anaplasma, Ehrlichia, and Rickettsia. Following our successful transformation of the human anaplasmosis agent, A. phagocytophilum, we produced plasmid constructs (a transposon bearing plasmid, pHimarAm-trTurboGFP-SS, and a transposase expression plasmid, pET28Am-trA7) designed to mediate random insertion of the TurboGFP and spectinomycin/streptomycin resistance genes by the Himar1 allele A7 into the A. marginale chromosome. In these trans constructs, expression of the fluorescent and the selectable markers on the transposon, and expression of the transposase are under control of the A. marginale tr promoter. Constructs were co-electroporated into A. marginale St. Maries purified from tick cell culture, and bacteria incubated for 2 months under selection with a combination of spectinomycin and streptomycin. At that time, ≤1% of tick cells contained colonies of brightly fluorescent Anaplasma, which eventually increased to infect about 80–90% of the cells. Cloning of the insertion site in E. coli and DNA sequence analyses demonstrated insertion of the entire plasmid pHimarAm-trTurboGFP-SS encoding the transposon in frame into the native tr region of A. marginale in an apparent single homologous crossover event not mediated by the transposase. Transformants are fastidious and require longer subculture intervals than wild type A. marginale. This result suggests that A. marginale, as well as possibly other species of Anaplasma and Ehrlichia, can be transformed using a strategy of homologous recombination. PMID:19837516

  5. Thermal energy transformer

    NASA Technical Reports Server (NTRS)

    Berdahl, C. M.; Thiele, C. L. (Inventor)

    1979-01-01

    For use in combination with a heat engine, a thermal energy transformer is presented. It is comprised of a flux receiver having a first wall defining therein a radiation absorption cavity for converting solar flux to thermal energy, and a second wall defining an energy transfer wall for the heat engine. There is a heat pipe chamber interposed between the first and second walls having a working fluid disposed within the chamber and a wick lining the chamber for conducting the working fluid from the second wall to the first wall. Thermal energy is transferred from the radiation absorption cavity to the heat engine.

  6. Banded transformer cores

    NASA Technical Reports Server (NTRS)

    Mclyman, C. W. T. (Inventor)

    1974-01-01

    A banded transformer core formed by positioning a pair of mated, similar core halves on a supporting pedestal. The core halves are encircled with a strap, selectively applying tension whereby a compressive force is applied to the core edge for reducing the innate air gap. A dc magnetic field is employed in supporting the core halves during initial phases of the banding operation, while an ac magnetic field subsequently is employed for detecting dimension changes occurring in the air gaps as tension is applied to the strap.

  7. Microbial transformation of pyrethrosin.

    PubMed

    Galal, A M

    2001-08-01

    Microbial transformation of the germacranolide pyrethrosin (1) using Rhizopus nigricans NRRL 1477 has resulted in the isolation of 6 alpha-acetoxy-1 beta,4 alpha-dihydroxy-5,7 alpha H,8 beta H-eudesm-11 beta,13-dihydro-8,12-olide (5), a new eudesmanolide-type metabolite, in addition to the previously reported eudesmanolides: 2, 3, 4, and 6. The structure elucidation of these metabolites was based primarily on 1D and 2D NMR analyses. The isolated metabolites exhibited cytotoxic, antifungal, and antiprotozoal activities. PMID:11520238

  8. A Fast Hermite Transform?

    PubMed Central

    Leibon, Gregory; Rockmore, Daniel N.; Park, Wooram; Taintor, Robert; Chirikjian, Gregory S.

    2008-01-01

    We present algorithms for fast and stable approximation of the Hermite transform of a compactly supported function on the real line, attainable via an application of a fast algebraic algorithm for computing sums associated with a three-term relation. Trade-offs between approximation in bandlimit (in the Hermite sense) and size of the support region are addressed. Numerical experiments are presented that show the feasibility and utility of our approach. Generalizations to any family of orthogonal polynomials are outlined. Applications to various problems in tomographic reconstruction, including the determination of protein structure, are discussed. PMID:20027202

  9. Computer simulation of martensitic transformations

    SciTech Connect

    Xu, Ping

    1993-11-01

    The characteristics of martensitic transformations in solids are largely determined by the elastic strain that develops as martensite particles grow and interact. To study the development of microstructure, a finite-element computer simulation model was constructed to mimic the transformation process. The transformation is athermal and simulated at each incremental step by transforming the cell which maximizes the decrease in the free energy. To determine the free energy change, the elastic energy developed during martensite growth is calculated from the theory of linear elasticity for elastically homogeneous media, and updated as the transformation proceeds.

  10. Chemical Transformations of Nanosilver in Biological Environments

    PubMed Central

    Liu, Jingyu; Wang, Zhongying; Liu, Frances D.; Kane, Agnes B.; Hurt, Robert H.

    2012-01-01

    The widespread use of silver nanoparticles (Ag-NPs) in consumer and medical products provides strong motivation for a careful assessment of their environmental and human health risks. Recent studies have shown that Ag-NPs released to the natural environment undergo profound chemical transformations that can affect silver bioavailability, toxicity, and risk. Less is known about Ag-NP chemical transformations in biological systems, though the medical literature clearly reports that chronic silver ingestion produces argyrial deposits consisting of silver-, sulfur-, and selenium-containing particulate phases. Here we show that Ag-NPs undergo a rich set of biochemical transformations, including accelerated oxidative dissolution in gastric acid, thiol binding and exchange, photoreduction of thiol- or protein-bound silver to secondary zero-valent Ag-NPs, and rapid reactions between silver surfaces and reduced selenium species. Selenide is also observed to rapidly exchange with sulfide in preformed Ag2S solid phases. The combined results allow us to propose a conceptual model for Ag-NP transformation pathways in the human body. In this model, argyrial silver deposits are not translocated engineered Ag-NPs, but rather secondary particles formed by partial dissolution in the GI tract followed by ion uptake, systemic circulation as organo-Ag complexes and immobilization as zero-valent Ag-NPs by photoreduction in light affected skin regions. The secondary Ag-NPs then undergo detoxifying transformations into sulfides, and further into selenides or Se/S mixed phases through exchange reactions. The formation of secondary particles in biological environments implies that Ag-NPs are not only a product of industrial nanotechnology, but have long been present in the human body following exposure to more traditional chemical forms of silver. PMID:23046098

  11. Fast Fourier transform telescope

    NASA Astrophysics Data System (ADS)

    Tegmark, Max; Zaldarriaga, Matias

    2009-04-01

    We propose an all-digital telescope for 21 cm tomography, which combines key advantages of both single dishes and interferometers. The electric field is digitized by antennas on a rectangular grid, after which a series of fast Fourier transforms recovers simultaneous multifrequency images of up to half the sky. Thanks to Moore’s law, the bandwidth up to which this is feasible has now reached about 1 GHz, and will likely continue doubling every couple of years. The main advantages over a single dish telescope are cost and orders of magnitude larger field-of-view, translating into dramatically better sensitivity for large-area surveys. The key advantages over traditional interferometers are cost (the correlator computational cost for an N-element array scales as Nlog⁡2N rather than N2) and a compact synthesized beam. We argue that 21 cm tomography could be an ideal first application of a very large fast Fourier transform telescope, which would provide both massive sensitivity improvements per dollar and mitigate the off-beam point source foreground problem with its clean beam. Another potentially interesting application is cosmic microwave background polarization.

  12. Image Transformations-Montserrat

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A slightly oblique digital photograph of Montserrat taken from the International Space Station was posted to Earth Observatory in December 2001. An Earth Observatory reader used widely available software to correct the oblique perspective and adjust the color. The story of how he modified the image includes step-by-step instructions that can be applied to other photographs. Photographs of Earth taken by astronauts have shaped our view of the Earth and are part of our popular culture because NASA makes them easily accessible to the public. Read the Transformations Story for more information. The original image was digital photograph number ISS002-E-9309, taken on July 9, 2001, from the International Space Station and was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth. Bill Innanen provided the transformed image and the story of how he did it.

  13. Polystyrene sulphonic acid resins with enhanced acid strength via macromolecular self-assembly within confined nanospace

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaomin; Zhao, Yaopeng; Xu, Shutao; Yang, Yan; Liu, Jia; Wei, Yingxu; Yang, Qihua

    2014-01-01

    Tightening environmental legislation is driving the chemical industries to develop efficient solid acid catalysts to replace conventional mineral acids. Polystyrene sulphonic acid resins, as some of the most important solid acid catalysts, have been widely studied. However, the influence of the morphology on their acid strength—closely related to the catalytic activity—has seldom been reported. Herein, we demonstrate that the acid strength of polystyrene sulphonic acid resins can be adjusted through their reversible morphology transformation from aggregated to swelling state, mainly driven by the formation and breakage of hydrogen bond interactions among adjacent sulphonic acid groups within the confined nanospace of hollow silica nanospheres. The hybrid solid acid catalyst demonstrates high activity and selectivity in a series of important acid-catalysed reactions. This may offer an efficient strategy to fabricate hybrid solid acid catalysts for green chemical processes.

  14. Bijective transformation circular codes and nucleotide exchanging RNA transcription.

    PubMed

    Michel, Christian J; Seligmann, Herv

    2014-04-01

    The C(3) self-complementary circular code X identified in genes of prokaryotes and eukaryotes is a set of 20 trinucleotides enabling reading frame retrieval and maintenance, i.e. a framing code (Arqus and Michel, 1996; Michel, 2012, 2013). Some mitochondrial RNAs correspond to DNA sequences when RNA transcription systematically exchanges between nucleotides (Seligmann, 2013a,b). We study here the 23 bijective transformation codes ?X of X which may code nucleotide exchanging RNA transcription as suggested by this mitochondrial observation. The 23 bijective transformation codes ?X are C(3) trinucleotide circular codes, seven of them are also self-complementary. Furthermore, several correlations are observed between the Reading Frame Retrieval (RFR) probability of bijective transformation codes ?X and the different biological properties of ?X related to their numbers of RNAs in GenBank's EST database, their polymerization rate, their number of amino acids and the chirality of amino acids they code. Results suggest that the circular code X with the functions of reading frame retrieval and maintenance in regular RNA transcription, may also have, through its bijective transformation codes ?X, the same functions in nucleotide exchanging RNA transcription. Associations with properties such as amino acid chirality suggest that the RFR of X and its bijective transformations molded the origins of the genetic code's machinery. PMID:24565870

  15. Transformations of emotional experience.

    PubMed

    de Cortiñas, Lia Pistiner

    2013-06-01

    In this paper the author approaches mental pain and the problems in a psychoanalytic treatment of patients with difficulties in the psychic transformation of their emotional experiences. The author is interested in the symbolic failure related to the obstruction of development of phantasies, dreams, dream-thoughts, etc. She differentiates symbolization disturbances related to hypertrophic projective identification from a detention of these primitive communications and emotional isolation. She puts forward the conjecture that one factor in the arrest of this development is the detention of projective identifications and that, when this primitive means of communication is re-established in a container-contained relationship of mutual benefit, this initiates the development of a symbolization process that can replace the pathological 'protection'. Another hypothesis she develops is that of inaccessible caesuras that, associated with the detention of projective identification, obstruct any integrative or interactive movement. This caesura and the detention of projective identifications affect mental functions needed for dealing with mental pain. The personality is left with precarious mental equipment for transforming emotional experiences. How can a psychoanalytical process stimulate the development of creative symbolization, transforming the emotional experiences and leading towards mental growth? The author approaches the clinical problem with the metaphor of the psychic birth of emotional experience. The modulation of mental pain in a container-contained relationship is a central problem for the development of the human mind. For discovering and giving a meaning to emotional experience, the infant depends on reverie, a function necessary in order to develop an evolved consciousness capable of being aware, which is different from the rudimentary consciousness that perceives but does not understand. The development of mature mental equipment is associated with the personality's attitude towards mental pain. The differentiation between psychotic, neurotic or autistic functioning depends on what defences are erected to avoid mental pain. The primary link between infant and mother is where the building of mental equipment takes place, through communicational forms that, to begin with, are not verbal. The author suggests the need for the development of an ideo-grammar (in gestures, paralinguistic forms, etc.) in primary relations, as the precursor forms that will become the matrix for the mental tools for dealing with emotional experiences in a mature way. The paper stresses the significance of the parental containing function for the development of symbolization of prenatal emotional experiences. This containment develops ideograms, transformations of sense impressions into proto-symbols, instruments that attenuate the traumatic experiences of helplessness. The author takes Bion's ideas about extending the notion of dream-work to an alpha function that goes on continually, day and night, transforming raw emotional experiences in a 'dream'. In order to acquire a meaning, facts need to be 'dreamed' in this extended sense. Meaning and truth are the nurture of the mind. Mental growth, the development of adequate tools--including reverie--for dealing with mental pain, seen from a psychoanalytic perspective including reverie, implies that the object becomes a provider of meanings. Analysis begins to aim primarily at the generation or expansion of the mental container, instead of predominantly working on unconscious contents as such. PMID:23781834

  16. Gabor transform in texture analysis

    NASA Astrophysics Data System (ADS)

    Chen, Chien-Chang; Chen, Chaur-Chin

    1994-10-01

    Gabor transform has recently been exploited to do texture analysis, including texture edge detection, texture segmentation/discrimination, and texture synthesis. For most of the applications using Gabor transform, people convolve the given texture image with a set of Gabor filters with some user specified parameters. Although the mathematical formulation of applications involve the Fourier transform, few have investigated mathematical properties of the relationship between Gabor filters and their Fourier transform. This paper mainly studies mathematical properties of real Gabor filters and their corresponding Fourier transform. The goal is to select a set of `interesting' Gabor filters, or say, a set of parameters for Gabor filters to do texture analysis. We demonstrate, by means of 3-D graphical displays, that a Gabor filter or its corresponding Fourier transform may have a single peak or double peaks according to different parameters. Experiments for texture discrimination are given to demonstrate the applications of Gabor transform.

  17. Distinctive transforming genes in x-ray-transformed mammalian cells

    SciTech Connect

    Borek, C.; Ong, A.; Mason, H.

    1987-02-01

    DNAs from hamster embryo cells and mouse C3H/10T1/2 cells transformed in vitro by x-irradiation into malignant cells transmit the radiation transformation phenotype by producing transformed colonies (transfectants) in two mouse recipient lines, the NIH 3T3 and C3H/101/2 cells, and in a rat cell line, the Rat-2 cells. DNAs from unirradiated cells or irradiated and visibly untransformed cells do not produce transformed colonies. The transfectant grow in agar and form tumors in nude mice. Treatment of the DNAs with restriction endonucleases prior to transfection indicates that the same transforming gene (oncogene) is present in each of the transformed mouse cells and is the same in each of the transformed hamster cells. Southern blot analysis of 3T3 or Rat-2 transfectants carrying oncogenes from radiation-transformed C3H/10T1/2 or hamster cells indicates that the oncogenes responsible for the transformation of 3T3 cells are not the Ki-ras, Ha-ras, N-ras genes, nor are they neu, trk, raf, abl, or fms. The work demonstrates that DNAs from mammalian cells transformed into malignancy by direct exposure in vitro to radiation contain genetic sequences with detectable transforming activity in three recipient cell lines. The results provide evidence that DNA is the target of radiation carcinogenesis induced at a cellular level in vitro. The experiments indicate that malignant radiogenic transformation in vitro of hamster embryo and mouse C3H/10T1/2 cells involves the activation of unique non-ras transforming genes, which heretofore have not been described.

  18. MICROBIAL TRANSFORMATION KINETICS OF XENOBIOTICS IN AQUATIC ENVIRONMENT

    EPA Science Inventory

    The microbiological transformation rates of four organic compounds, the butoxy-ethylester of 2,4-dichlorophenoxyacetic acid (2,4-DBE), p-cresol, alpha-naphthol and quinoline, added to natural water samplers were examined in laboratory experiments. Graphical analysis of the data w...

  19. NO/sub 2/ transformation in cloud droplets

    SciTech Connect

    Gertler, A.W.; Whitbeck, M.R.; Miller, D.F.

    1985-01-01

    A major pathway for the atmospheric transformation of pollutants is heterogeneous conversion of absorbed gases in liquid droplets. In the case of acidic precursors such as sulfur dioxide and the oxides of nitrogen, these species are removed from the air at the expense of acidifying cloud or fog. Evaporation of these droplets may in turn yield a modified aerosol containing the products of the transformation processes. Thus, the ultimate fate of acidic precursors and the chemical species produced in cloud droplets are highly dependent on liquid phase chemistry and cloud microphysics. The processes and time scale of nucleation, condensation and droplet growth and duration can be qualitatively represented by experimental simulations in the DRI cloud chamber. This paper compares previously reported results of measurements of NO/sub 2/ transformation in simulated cloud with results of other experimental methods. A series of bulk water experiments conducted in order to resolve the discrepencies between the techniques is also described.

  20. A piezoelectric transformer

    NASA Technical Reports Server (NTRS)

    Won, C. C.

    1993-01-01

    This work describes a modeling and design method whereby a piezoelectric system is formulated by two sets of second-order equations, one for the mechanical system, and the other for the electrical system, coupled through the piezoelectric effect. The solution to this electromechanical coupled system gives a physical interpretation of the piezoelectric effect as a piezoelectric transformer that is a part of the piezoelectric system, which transfers the applied mechanical force into a force-controlled current source, and short circuit mechanical compliance into capacitance. It also transfers the voltage source into a voltage-controlled relative velocity input, and free motional capacitance into mechanical compliance. The formulation and interpretation simplify the modeling of smart structures and lead to physical insight that aids the designer. Due to its physical realization, the smart structural system can be unconditional stable and effectively control responses. This new concept has been demonstrated in three numerical examples for a simple piezoelectric system.

  1. General linear chirplet transform

    NASA Astrophysics Data System (ADS)

    Yu, Gang; Zhou, Yiqi

    2016-03-01

    Time-frequency (TF) analysis (TFA) method is an effective tool to characterize the time-varying feature of a signal, which has drawn many attentions in a fairly long period. With the development of TFA, many advanced methods are proposed, which can provide more precise TF results. However, some restrictions are introduced inevitably. In this paper, we introduce a novel TFA method, termed as general linear chirplet transform (GLCT), which can overcome some limitations existed in current TFA methods. In numerical and experimental validations, by comparing with current TFA methods, some advantages of GLCT are demonstrated, which consist of well-characterizing the signal of multi-component with distinct non-linear features, being independent to the mathematical model and initial TFA method, allowing for the reconstruction of the interested component, and being non-sensitivity to noise.

  2. [Transformational leadership in nursing].

    PubMed

    Strapasson, Maria Rejane; Medeiros, Cssia R G

    2009-01-01

    This qualitative research aimed at verifying if the presuppositions of Transformational Leadership are present in the nurses practice in a medium size hospital in the countryside of Rio Grande do Sul. The researched people were eleven head nurses in different sectors of the hospital, who have been working for one year or more in the inquired medical institution. The tools used for the research was a semi-structured interview. The data have been analysed through content analyses method, in which five categories emerged: the meaning of leadership; essential abilities for leadership activity; leadership ability in everyday nurse activity; participation of the Institution in leadership development; and the resistance of nurses to the changing process. Some of the presuppositions are identified and noticed as important, although not totally present in everyday activity of nurses. PMID:19430681

  3. Fourier Transform Spectrometer System

    NASA Technical Reports Server (NTRS)

    Campbell, Joel F. (Inventor)

    2014-01-01

    A Fourier transform spectrometer (FTS) data acquisition system includes an FTS spectrometer that receives a spectral signal and a laser signal. The system further includes a wideband detector, which is in communication with the FTS spectrometer and receives the spectral signal and laser signal from the FTS spectrometer. The wideband detector produces a composite signal comprising the laser signal and the spectral signal. The system further comprises a converter in communication with the wideband detector to receive and digitize the composite signal. The system further includes a signal processing unit that receives the composite signal from the converter. The signal processing unit further filters the laser signal and the spectral signal from the composite signal and demodulates the laser signal, to produce velocity corrected spectral data.

  4. Imaging Fourier Transform Spectrometer

    SciTech Connect

    Bennett, C.L.; Carter, M.R.; Fields, D.J.; Hernandez, J.

    1993-04-14

    The operating principles of an Imaging Fourier Transform Spectrometer (IFTS) are discussed. The advantages and disadvantages of such instruments with respect to alternative imaging spectrometers are discussed. The primary advantages of the IFTS are the capacity to acquire more than an order of magnitude more spectral channels than alternative systems with more than an order of magnitude greater etendue than for alternative systems. The primary disadvantage of IFTS, or FTS in general, is the sensitivity to temporal fluctuations, either random or periodic. Data from the IRIFTS (ir IFTS) prototype instrument, sensitive in the infrared, are presented having a spectral sensitivity of 0.01 absorbance units, a spectral resolution of 6 cm{sup {minus}1} over the range 0 to 7899 cm{sup {minus}1}, and a spatial resolution of 2.5 mr.

  5. Acid rain

    SciTech Connect

    Stensland, G.J.

    1983-11-01

    A series of definitions for the field of acid rain studies are presented. Protocols for acid rain sampling and monitoring are also presented. A procedure for calculatory precipitation pH is discussed. 11 references, 1 table.

  6. Aristolochic Acids

    Cancer.gov

    Aristolochic acids are a group of acids found naturally in many types of plants known as Aristolochia (birthworts or pipevines) and some types of plants known as Asarum (wild ginger), which grow worldwide.

  7. 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 ...

  8. 7 transformations of leadership.

    PubMed

    Rooke, David; Torbert, William R

    2005-04-01

    Most developmental psychologists agree that what differentiates one leader from another is not so much philosophy of leadership, personality, or style of management. Rather, it's internal "action logic"--how a leader interprets the surroundings and reacts when his or her power or safety is challenged. Relatively few leaders, however, try to understand their action logic, and fewer still have explored the possibility of changing it. They should, because leaders who undertake this voyage of personal understanding and development can transform not only their own capabilities but also those of their companies. The authors draw on 25 years of consulting experience and collaboration with psychologist Susanne Cook-Greuter to present a typology of leadership based on the way managers personally make sense of the world around them. Rooke and Torbert classify leaders into seven distinct actionlogic categories: Opportunists, Diplomats, Experts, Achievers, Individualists, Strategists, and Alchemists-the first three associated with below-average performance, the latter four with medium to high performance. These leadership styles are not fixed, the authors say, and executives who are willing to work at developing themselves and becoming more self-aware can almost certainly move toward one of the more effective action logics. A Diplomat, for instance, can succeed through hard work and self-reflection at transforming himself into a Strategist. Few people may become Alchemists, but many will have the desire and potential to become Individualists and Strategists. Corporations that help their executives and leadership teams to examine their action logics can reap rich rewards. PMID:15807040

  9. The effects of hydroxy fatty acids on the hyphal branching of germinated spores of AM fungi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abietic acid (Aba), dehydroabietic acid (DAba), and 2-hydroxytetradecanoic acid (2-HTDA) were identified by Fourier Transform Ion Cyclotron Mass Spectroscopy and found to be elevated in the exudate of Ri T-DNA transformed carrot roots that were grown in the absence relative to the presence of phosph...

  10. EFFECTS OF MICROBIAL COMMUNITY INTERACTIONS ON TRANSFORMATION RATES OF XENOBIOTIC CHEMICALS

    EPA Science Inventory

    The effects of culture filtrates, mixed populations, and common microbial exudates on bacterial transformations of three agricultural and industrial chemicals were investigated. Test chemicals included methyl parathion, diethyl phthalate, and 2,4-dichlorophenoxyacetic acid butoxy...

  11. Highly efficient transformation protocol for plum (Prunus domestica L.).

    PubMed

    Petri, Csar; Scorza, Ralph; Srinivasan, Chinnathambi

    2012-01-01

    A high-throughput transformation system for plum has been developed using hypocotyl slices excised from zygotic embryos as the source of explants. The hypocotyl slices are infected in an Agrobacterium tumefaciens suspension and then cocultivated for 3 days in shoot regeneration MS basal medium supplemented with 9 ?M 2,4-dichlorophenoxyacetic acid. Transgenic shoots are regenerated in a medium containing 7.5 ?M thidiazuron and elongated in a medium containing 3 ?M benzyladenine in the presence of 80 mg/L kanamycin in both media. Transformed shoots are rooted in MS basal medium supplemented with 5 ?M NAA and 40 mg/L kanamycin. The transgenic plants are acclimatized in a growth chamber and transferred to a temperature-controlled greenhouse. This protocol has allowed transformation efficiencies up to 42% and enabled the production of self-rooted transgenic plum plants within 6 months of transformation. PMID:22351009

  12. Advanced concepts for transformers pressboard dielectric constant and mechanical strength

    NASA Astrophysics Data System (ADS)

    1982-03-01

    Of the numerous electrical considerations in a material, the value of the dielectric constant serves as an important criterion in designing proper insulation systems. Ways to reduce the dielectric constant of solid (fibrous) insulating materials were investigated. A literature search was made on cellulosic and synthetic fibers and also additives which offered the potential for dielectric constant reduction of the solid insulation. Sample board structures were produced in the laboratory and tested for electrical, mechanical and chemical characteristics. Electrical tests determined the suitability of the material at transformer test and operating conditions. The mechanical tests established the physical characteristics of the modified board structures. Chemical tests checked the conductivity of the aqueous extract, acidity, and ash content. Further, compatibility with transformer oil and some aging tests were performed. An actual computer transformer design was made based on one of the modified board structures and the reduction in core steel and transformer losses were shown.

  13. A novel method to transform prokaryotic cells using shock waves

    NASA Astrophysics Data System (ADS)

    Nataraja, K. N.; Udayakumar, M.; Jagadeesh, G.

    The transgenic approach that is being used to study gene function or to improve the efficiency of crop plants/organisms involves transformation of a wide range of cells, tissues, and organisms with nucleic acid. In this study we report a new micro- shock assisted prokaryotic cell transformation technique. An underwater electric discharge based shock wave generator (25 kV; 150 m A; high voltage capacitor) has been designed and fabricated to carry out the prokaryotic cell transformation experiments. Test tubes with bacterial cell suspension with appropriate plasmid DNA, immersed in water are exposed to shock wave loading (typical overpressure 130 bar). The transformation efficiency of samples of the prokaryotic cells exposed to shock waves is very high compared to conventional methods.

  14. Amino acid management in cancer

    PubMed Central

    Tsun, Zhi-Yang; Possemato, Richard

    2016-01-01

    Amino acids have a dual role in cellular metabolism, as they are both the building blocks for protein synthesis and intermediate metabolites which fuel other biosynthetic reactions. Recent work has demonstrated that deregulation of both arms of amino acid management are common alterations seen in cancer. Among the most highly consumed nutrients by cancer cells are the amino acids glutamine and serine, and the biosynthetic pathways that metabolize them are required in various cancer subtypes and the object of current efforts to target cancer metabolism. Also altered in cancer are components of the machinery which sense amino acid sufficiency, nucleated by the mechanistic target of rapamycin (mTOR), a key regulator of cell growth via modulation of key processes including protein synthesis and autophagy. The precise ways in which altered amino acid management supports cellular transformation remain mostly elusive, and a fuller mechanistic understanding of these processes will be important for efforts to exploit such alterations for cancer therapy. PMID:26277542

  15. Transformation plasticity in ductile solids

    SciTech Connect

    Olson, G.B.

    1993-02-01

    Research has addressed the role of martensitic transformation plasticity in the enhancement of toughness in high-strength austenitic steels, and the enhancement of formability in multiphase low-alloy sheet steels. In the austenitic steels, optimal processing conditions have been established to achieve a significant increase in strength level, in order to investigate the interaction of strain-induced transformation with the microvoid nucleation and shear localization mechanisms operating at ultrahigh strength levels. The stress-state dependence of transformation and fracture mechanisms has been investigated in model alloys, comparing behavior in uniaxial tension and blunt-notch tension specimens. A numerical constitutive model for transformation plasticity has been reformulated to allow a more thorough analysis of transformation/fracture interactions. Processing of a new low alloy steel composition has been optimized to stabilize retained austenite by isothermal bainitic transformation after intercritical annealing. Preliminary results show a good correlation of uniform ductility with the austenite amount and stability.

  16. BIOCONVERSION OF ALPHA-LINOLENIC ACID BY CLAVIBACTER SP. ALA2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Microbial enzyme systems transform unsaturated fatty acids to functional substances. Previously, we reported that Clavibacter sp. ALA2 converted linoleic acid to unique cyclic fatty acids such as diepoxy bicyclic fatty acids (DEOA) and tetrahydrofuranyl fatty acids (THFA) as well as trihydroxy fatty...

  17. FORMATION OF CYCLIC PRODUCTS FROM POLYUNSATURATED FATTY ACIDS BY CLAVIBACTER SP. ALA2

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Purpose of experiment: Microbial transformation of unsaturated fatty acids to functional substances. In a previous study, Clavibacter sp. ALA2 was reported to convert linoleic acid into unique cyclic fatty acids such as diepoxy bicyclic fatty acids (DEOA) and tetrahydrofuranyl fatty acids (THFA) a...

  18. Cereal transformation through particle bombardment

    NASA Technical Reports Server (NTRS)

    Casas, A. M.; Kononowicz, A. K.; Bressan, R. A.; Hasegawa, P. M.; Mitchell, C. A. (Principal Investigator)

    1995-01-01

    The review focuses on experiments that lead to stable transformation in cereals using microprojectile bombardment. The discussion of biological factors that affect transformation examines target tissues and vector systems for gene transfer. The vector systems include reporter genes, selectable markers, genes of agronomic interest, and vector constructions. Other topics include physical parameters that affect DNA delivery, selection of stably transformed cells and plant regeneration, and analysis of gene expression and transmission to the progeny.

  19. Reflectional transformation for structural stiffness

    SciTech Connect

    Vashi, K.M.

    1990-01-01

    This paper presents a structural reflection-related transformation for structural stiffness. The stiffness transformation addresses reflection of a structure about any of the three coordinate planes and renders the desired stiffness matrix using a stiffness matrix for the same structure before reflection. This transformation is elegant and simple, provides an efficient and technically rigorous approach to derive the required stiffness matrix without structural remodeling, and can be readily programmed to quickly perform the required matrix manipulations. 2 figs.

  20. Transformation Systems at NASA Ames

    NASA Technical Reports Server (NTRS)

    Buntine, Wray; Fischer, Bernd; Havelund, Klaus; Lowry, Michael; Pressburger, TOm; Roach, Steve; Robinson, Peter; VanBaalen, Jeffrey

    1999-01-01

    In this paper, we describe the experiences of the Automated Software Engineering Group at the NASA Ames Research Center in the development and application of three different transformation systems. The systems span the entire technology range, from deductive synthesis, to logic-based transformation, to almost compiler-like source-to-source transformation. These systems also span a range of NASA applications, including solving solar system geometry problems, generating data analysis software, and analyzing multi-threaded Java code.

  1. Contamination of the transformer oil of power transformers and shunting reactors by metal-containing colloidal particles

    SciTech Connect

    L'vov, S. Yu.; Komarov, V. B.; Bondareva, V. N.; Seliverstov, A. F.; Lyut'ko, E. O.; L'vov, Yu. N.; Ershov, B. G.

    2011-05-15

    The results of a measurement of the contamination of the oil in 66 transformers by metal-containing colloidal particles, formed as a result of the interaction of the oil with the structural materials (the copper of the windings, the iron of the tank and core etc.), and also the results of measurements of the optical turbidity of the oil in 136 transformers when they were examined at the Power Engineering Research and Development Center Company are presented. Methods of determining the concentration of copper and iron in transformer oil are considered. The limiting values of the optical turbidity factors, the copper and iron content are determined. These can serve as a basis for taking decisions on whether to replace the silica gel of the filters for continuously purifying the oil of power transformers and the shunting reactors in addition to the standardized oil contamination factors, namely, the dielectric loss tangent and the acidity number of the oil.

  2. cDNA sequence of human transforming gene hst and identification of the coding sequence required for transforming activity

    SciTech Connect

    Taira, M.; Yoshida, T.; Miyagawa, K.; Sakamoto, H.; Terada, M.; Sugimura, T.

    1987-05-01

    The hst gene was originally identified as a transforming gene in DNAs from human stomach cancers and from a noncancerous portion of stomach mucosa by DNA-mediated transfection assay using NIH3T3 cells. cDNA clones of hst were isolated from the cDNA library constructed from poly(A)/sup +/ RNA of a secondary transformant induced by the DNA from a stomach cancer. The sequence analysis of the hst cDNA revealed the presence of two open reading frames. When this cDNA was inserted into an expression vector containing the simian virus 40 promoter, it efficiently induced the transformation of NIH3T3 cells upon transfection. It was found that one of the reading frames, which coded for 206 amino acids, was responsible for the transforming activity.

  3. Medical data transformation using rewriting

    PubMed Central

    Ashish, Naveen; Toga, Arthur W.

    2015-01-01

    This paper presents a system for declaratively transforming medical subjects' data into a common data model representation. Our work is part of the “GAAIN” project on Alzheimer's disease data federation across multiple data providers. We present a general purpose data transformation system that we have developed by leveraging the existing state-of-the-art in data integration and query rewriting. In this work we have further extended the current technology with new formalisms that facilitate expressing a broader range of data transformation tasks, plus new execution methodologies to ensure efficient data transformation for disease datasets. PMID:25750622

  4. Microbial Transformation of Ibuprofen by a Nocardia Species

    PubMed Central

    Chen, Yijun; Rosazza, John P. N.

    1994-01-01

    The carboxylic acid functional group of ibuprofen [?-methyl-4-(2-methylpropyl) benzene acetic acid] is reduced to the corresponding alcohol and subsequently esterified to the acetate derivative by cultures of Nocardia species strain NRRL 5646. The alcohol and ester microbial transformation products were isolated, and their structures were determined by 1H and 13C nuclear magnetic resonance spectroscopy and mass spectrometry. By derivatization of synthetic and microbiologically produced ibuprofen alcohols with S(+)-O-acetylmandelic acid, nuclear magnetic resonance analysis indicated that the carboxylic acid reductase of Nocardia sp. is R enantioselective, giving alcohol products with an enantiomeric excess of 61.2%. The R enantioselectivity of the carboxylic acid reductase enzyme system was confirmed by using cell extracts together with ATP and NADPH in the reduction of isomeric ibuprofens. PMID:16349237

  5. Photocatalytic transformation of acesulfame: Transformation products identification and embryotoxicity study.

    PubMed

    Li, Adela Jing; Schmitz, Oliver J; Stephan, Susanne; Lenzen, Claudia; Yue, Patrick Ying-Kit; Li, Kaibin; Li, Huashou; Leung, Kelvin Sze-Yin

    2016-02-01

    Artificial sweeteners have been recognized as emerging contaminants due to their wide application, environmental persistence and ubiquitous occurrence. Among them, acesulfame has attracted much attention. After being discharged into the environment, acesulfame undergoes photolysis naturally. However, acesulfame photodegradation behavior and identity of its transformation products, critical to understanding acesulfame's environmental impact, have not been thoroughly investigated. The present study aimed to fill this knowledge gap by a laboratory simulation study in examining acesulfame transformation products and pathways under UV-C photolysis in the presence of TiO2. Photodegradation products of acesulfame were isolated and analyzed using the LC-IM-QTOF-MS coupled with LC Ion Trap MS in the MS(n) mode. Our results show six new transformation products that have not been previously identified. The molecular structures and transformation pathways were proposed. Further embryotoxicity tests showed that acesulfame transformation products at the low g L(-1) level produced significant adverse effects in tail detachment, heart rate, hatching rate and survival rate during fish embryo development. The identification of additional transformation products with proposed transformation pathways of acesulfame, the increased toxicity of acesulfame after photolysis, and the fact that the accumulation of acesulfame transformation products is increasingly likely make acesulfame contamination even more important. Water resource control agencies need to consider legislation regarding acesulfame and other artificial sweeteners, while further studies are carried out, in order to protect the safety of this most vital resource. PMID:26630044

  6. Logarithmic Transformations in Regression: Do You Transform Back Correctly?

    ERIC Educational Resources Information Center

    Dambolena, Ismael G.; Eriksen, Steven E.; Kopcso, David P.

    2009-01-01

    The logarithmic transformation is often used in regression analysis for a variety of purposes such as the linearization of a nonlinear relationship between two or more variables. We have noticed that when this transformation is applied to the response variable, the computation of the point estimate of the conditional mean of the original response…

  7. Color image encryption based on gyrator transform and Arnold transform

    NASA Astrophysics Data System (ADS)

    Sui, Liansheng; Gao, Bo

    2013-06-01

    A color image encryption scheme using gyrator transform and Arnold transform is proposed, which has two security levels. In the first level, the color image is separated into three components: red, green and blue, which are normalized and scrambled using the Arnold transform. The green component is combined with the first random phase mask and transformed to an interim using the gyrator transform. The first random phase mask is generated with the sum of the blue component and a logistic map. Similarly, the red component is combined with the second random phase mask and transformed to three-channel-related data. The second random phase mask is generated with the sum of the phase of the interim and an asymmetrical tent map. In the second level, the three-channel-related data are scrambled again and combined with the third random phase mask generated with the sum of the previous chaotic maps, and then encrypted into a gray scale ciphertext. The encryption result has stationary white noise distribution and camouflage property to some extent. In the process of encryption and decryption, the rotation angle of gyrator transform, the iterative numbers of Arnold transform, the parameters of the chaotic map and generated accompanied phase function serve as encryption keys, and hence enhance the security of the system. Simulation results and security analysis are presented to confirm the security, validity and feasibility of the proposed scheme.

  8. Bioenergy and African transformation.

    PubMed

    Lynd, Lee R; Sow, Mariam; Chimphango, Annie Fa; Cortez, Luis Ab; Brito Cruz, Carlos H; Elmissiry, Mosad; Laser, Mark; Mayaki, Ibrahim A; Moraes, Marcia Afd; Nogueira, Luiz Ah; Wolfaardt, Gideon M; Woods, Jeremy; van Zyl, Willem H

    2015-01-01

    Among the world's continents, Africa has the highest incidence of food insecurity and poverty and the highest rates of population growth. Yet Africa also has the most arable land, the lowest crop yields, and by far the most plentiful land resources relative to energy demand. It is thus of interest to examine the potential of expanded modern bioenergy production in Africa. Here we consider bioenergy as an enabler for development, and provide an overview of modern bioenergy technologies with a comment on application in an Africa context. Experience with bioenergy in Africa offers evidence of social benefits and also some important lessons. In Brazil, social development, agricultural development and food security, and bioenergy development have been synergistic rather than antagonistic. Realizing similar success in African countries will require clear vision, good governance, and adaptation of technologies, knowledge, and business models to myriad local circumstances. Strategies for integrated production of food crops, livestock, and bioenergy are potentially attractive and offer an alternative to an agricultural model featuring specialized land use. If done thoughtfully, there is considerable evidence that food security and economic development in Africa can be addressed more effectively with modern bioenergy than without it. Modern bioenergy can be an agent of African transformation, with potential social benefits accruing to multiple sectors and extending well beyond energy supply per se. Potential negative impacts also cut across sectors. Thus, institutionally inclusive multi-sector legislative structures will be more effective at maximizing the social benefits of bioenergy compared to institutionally exclusive, single-sector structures. PMID:25709714

  9. Image transformations and blurring.

    PubMed

    Domke, Justin; Aloimonos, Yiannis

    2009-05-01

    Since cameras blur the incoming light during measurement, different images of the same surface do not contain the same information about that surface. Thus, in general, corresponding points in multiple views of a scene have different image intensities. While multiple-view geometry constrains the locations of corresponding points, it does not give relationships between the signals at corresponding locations. This paper offers an elementary treatment of these relationships. We first develop the notion of "ideal" and "real" images, corresponding to, respectively, the raw incoming light and the measured signal. This framework separates the filtering and geometric aspects of imaging. We then consider how to synthesize one view of a surface from another; if the transformation between the two views is affine, it emerges that this is possible if and only if the singular values of the affine matrix are positive. Next, we consider how to combine the information in several views of a surface into a single output image. By developing a new tool called "frequency segmentation," we show how this can be done despite not knowing the blurring kernel. PMID:19299857

  10. Parallel fast gauss transform

    SciTech Connect

    Sampath, Rahul S; Sundar, Hari; Veerapaneni, Shravan

    2010-01-01

    We present fast adaptive parallel algorithms to compute the sum of N Gaussians at N points. Direct sequential computation of this sum would take O(N{sup 2}) time. The parallel time complexity estimates for our algorithms are O(N/n{sub p}) for uniform point distributions and O( (N/n{sub p}) log (N/n{sub p}) + n{sub p}log n{sub p}) for non-uniform distributions using n{sub p} CPUs. We incorporate a plane-wave representation of the Gaussian kernel which permits 'diagonal translation'. We use parallel octrees and a new scheme for translating the plane-waves to efficiently handle non-uniform distributions. Computing the transform to six-digit accuracy at 120 billion points took approximately 140 seconds using 4096 cores on the Jaguar supercomputer. Our implementation is 'kernel-independent' and can handle other 'Gaussian-type' kernels even when explicit analytic expression for the kernel is not known. These algorithms form a new class of core computational machinery for solving parabolic PDEs on massively parallel architectures.

  11. Transformation Narratives in Academic Practice

    ERIC Educational Resources Information Center

    Kligyte, Giedre

    2011-01-01

    This paper reports an investigation of "transformation narratives" emerging from early career academics' reflective writing. The pieces of writing analysed describe self-initiated teaching development activities embedded in the early career academics' practice. Using a transformative learning framework, the analysis reveals the following changes

  12. Elliptic systems and numerical transformations

    NASA Technical Reports Server (NTRS)

    Mastin, C. W.; Thompson, J. F.

    1976-01-01

    Properties of a transformation method, which was developed for solving fluid dynamic problems on general two dimensional regions, are discussed. These include construction error of the transformation and applications to mesh generation. An error and stability analysis for the numerical solution of a model parabolic problem is also presented.

  13. Transformational Grammar and Cognitive Psycholinguistics.

    ERIC Educational Resources Information Center

    Lester, Mark

    1973-01-01

    An overview of Noam Chomsky's theories about transformational grammar and phonology is given. Since Chomsky was interested in characterizing what it is to know a language, the ways in which we demonstrate knowledge of our native language are discussed in detail. Particular emphasis is placed on describing how the transformational approach actually…

  14. Towards Transformative Leadership in Education

    ERIC Educational Resources Information Center

    van Oord, Lodewijk

    2013-01-01

    This article argues that an educational organization's type of leadership will to a very large extent determine the quality of personal transformation it instigates among its stakeholders. Focusing on the importance of transformative leadership, such leadership will be viewed as a critical and collaborative process in which school-based

  15. Student Services Revitalization/Transformation

    ERIC Educational Resources Information Center

    Pipitone, Brenda; Poirer, Wayne

    2011-01-01

    Over a two year period, a multidisciplinary team developed and implemented a plan to transform the delivery of student services at George Brown College in Toronto. It was a plan that called upon the College to fundamentally overhaul student services, but more importantly, to transform the service culture at the College through the students'

  16. Transformative Learning: Mutinous Thoughts Revisited

    ERIC Educational Resources Information Center

    Newman, Michael

    2014-01-01

    The author finds himself rereading an article he wrote several years ago, in which he questioned transformative learning. He recalls some of his reasons for writing the article, and considers his present position. He reflects on the understanding of consciousness that underlies much of the literature on transformative learning, and compares it

  17. Transformative Learning: Mutinous Thoughts Revisited

    ERIC Educational Resources Information Center

    Newman, Michael

    2014-01-01

    The author finds himself rereading an article he wrote several years ago, in which he questioned transformative learning. He recalls some of his reasons for writing the article, and considers his present position. He reflects on the understanding of consciousness that underlies much of the literature on transformative learning, and compares it…

  18. Hartley transform and its properties

    SciTech Connect

    Lideng, G. )

    1992-01-01

    Hartley Transform (HT) is an integral transform similar to Fourier Transform (FT) and it inherits most FT properties. fast Hartley Transform (FHT) can be achieved by using the structures similar to that in Fast Fourier Transform (FFT). However, HT has two advantages over FT: the same forward and inverse transforms, and real number transform. As a result, HT is faster than FT because the internal storage needed in real number operation is half as mush as that in complex number operation. Hence, in many data processings with FT, such as filtering, forward modeling, migration and so on, HT results in faster operation and less internal storage than FT does. HT original formulae are derived from FT circular function expressions. In this paper, the relationship between HT and ft or Hilbert transform is analyzed in detail. HT properties are summed by comparing with FT, and they are extended to discrete HT and multidimensional HT. HT and FT have similar or same properties, sot ht widely used FT program can be easy converted into HT program, resulting in faster seismic data processing.

  19. Aerodynamic coefficients and transformation tables

    NASA Technical Reports Server (NTRS)

    Ames, Joseph S

    1918-01-01

    The problem of the transformation of numerical values expressed in one system of units into another set or system of units frequently arises in connection with aerodynamic problems. Report contains aerodynamic coefficients and conversion tables needed to facilitate such transformation. (author)

  20. Transformational Professional Learning, February 2004

    ERIC Educational Resources Information Center

    National Staff Development Council, 2004

    2004-01-01

    "Transformational Professional Learning" is a periodically published e-newsletter designed to influence what educational leaders think, say, and do to improve teaching and learning by promoting deep understanding of important issues, the transformation of beliefs and assumptions, and a stream of powerful goal-focused actions. There are two…