Sample records for telluric acid transformations

  1. Telluric currents in pipelines

    Microsoft Academic Search

    L. Trichtchenko

    2004-01-01

    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

  2. Geomagnetically Induced Currents / Telluric Currents and Potential for Power

    E-print Network

    Schrijver, Karel

    Network Also Increases GIC Risk by 7 Times! #12;Geomagnetic Storms & Transformer Failures ­ Historic Trends IEEE Survey of GSU Transformer Failures #12;1989-1991 IEEE Survey of GSU Transformer Failures DataGeomagnetically Induced Currents / Telluric Currents and Potential for Power System Impacts from

  3. Temporal variability of the telluric sodium layer

    E-print Network

    D. S. Davis; P. Hickson; G. Herriot; C. Y. She

    2006-09-12

    The temporal variability of the telluric sodium layer is investigated by analyzing 28 nights of data obtained with the Colorado State University LIDAR experiment. The mean height power spectrum of the sodium layer was found to be well fit by a power law over the observed range of frequencies, 10 microhertz to 4 millhertz. The best fitting power law was found to be 10^\\beta \

  4. Temporal variability of the telluric sodium layer

    E-print Network

    Davis, D S; Herriot, G; She, C Y

    2006-01-01

    The temporal variability of the telluric sodium layer is investigated by analyzing 28 nights of data obtained with the Colorado State University LIDAR experiment. The mean height power spectrum of the sodium layer was found to be well fit by a power law over the observed range of frequencies, 10 microhertz to 4 millhertz. The best fitting power law was found to be 10^\\beta \

  5. Temporal variability of the telluric sodium layer

    Microsoft Academic Search

    D. Saul Davis; Paul Hickson; Glen Herriot; Chiao-Yao She

    2006-01-01

    The temporal variability of the telluric sodium layer is investigated by analyzing 28 nights of data obtained with the Colorado State University LIDAR experiment. The mean height power spectrum of the sodium layer was found to be well fitted by a power law over the observed range of frequencies, 10 muHz to 4 mHz. The best-fitting power law was found

  6. 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.

  7. MICROBIAL TRANSFORMATION OF ESTERS OF CHLORINATED CARBOXYLIC ACIDS

    EPA Science Inventory

    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 grou...

  8. Chemical transformations of methane in trifluoroacetic acid

    NASA Astrophysics Data System (ADS)

    Vishnetskaya, M. V.; Svichkarev, O. M.; Budynina, E. M.; Mel'nikov, M. Ya.

    2013-12-01

    The reaction of methane conversion in anhydrous trifluoroacetic acid (TFA) is shown to take place at room temperature and atmospheric pressure and to result in the formation of a resinous product. Signals of ions with molecular weights of 684 and 700 are observed in MALDI-TOF spectra of the dry residue of methane conversion products.

  9. Ultra-low temperature processing of barium tellurate dielectrics

    NASA Astrophysics Data System (ADS)

    Kwon, Do-Kyun

    Ceramics, metals and polymers have unique electrical properties that are combined for electronic devices and systems. It necessitates lower processing temperatures for ceramics to be compatible with metal and polymer systems. In this thesis, the synthesis, crystal structure, and dielectric properties of barium tellurate are studied for temperatures between 500 and 900°C. Barium tellurate dielectric ceramics (BaTe4O9, BaTe 2O5, BaTe2O6, BaTeO3, BaTeO 4, and Ba2TeO5) are extensively investigated as new LTCC (Low-Temperature Cofired Ceramics) dielectric systems integrated with low resistivity metal electrodes such as silver and aluminum for microwave application. Studies on the phase formation and crystal structure through thermal analyses (Differential Scanning Calorimetry and Thermogravimetric Analysis, DSC-TGA) and X-ray diffraction phase analysis attest that barium tellurates are formed in the temperature range of 500 ˜ 900°C, through the sequential phase formations from Te-rich to Ba-rich phases. The oxygen coordination of the tellurium ion progresses from TeO4 to TeO6 via TeO 3+1 and TeO3 with increasing barium content as confirmed by structural analysis using infrared spectroscopy. High density barium tellurate ceramics are achieved at temperatures as low as 550°C, which provides the potential to be co-fired with low-melting aluminum metal electrodes in LTCC processing. Dielectric permittivity, loss, and temperature stability of barium tellurate dielectric ceramics were measured from 100 Hz to 13 GHz. Barium tellurate ceramics exhibit excellent microwave dielectric properties with intermediate dielectric permittivities and high quality factors (Q). The dielectric properties at microwave frequencies are epsilonr = 17.5, Qxf = 54700 GHz, TCf = -90 ppm/°C for BaTe4O9, epsilonr = 21, Qxf = 50300 GHz, TCf = -51 ppm/°C for BaTe2O6, epsilonr = 10, Qxf = 34000 GHz, TCf = -54 ppm/°C for BaTeO3, and epsilonr = 17, Qx f = 49600 GHz, TCf = -124 ppm/°C for Ba 2TeO5. Co-firing studies of barium tellurate ceramics with metal electrodes establish new LTCC systems for microwave devices. Chemical compatibility of barium tellurates with silver electrodes was achieved in the barium rich compositions. Ba2TeO5 was found to be covetable with silver electrodes at 850°C by adding CuO and B2O3 as fluxing agents. During the co-firing, a thin interfacial layer of AgTe is metastable according to the thermodynamic equilibrium between the Ba2TeO5-Ag/Ag 2O pseudo-binary system. A breakthrough LTCC technology with aluminum is based upon the ultra-low processing temperature and chemical compatibility of BaTe4O 9, which enables co-firing and fabrication of multilayer ceramic capacitors (MLCCs) with aluminum inner electrodes. The aluminum base metal electrode (BME) BaTe4O9 MLCCs provide good dielectric properties of epsilonr = 17.5, TCepsilon = 100 ppm/°C, and tan delta = 2.1 x 10-3 (Q ? 500) at 1 MHz, which are suitable for the class-1 MLCCs. Aluminum microstrip ring resonators on the BaTe4O9 substrates realized good electromagnetic performance of the new materials at microwave frequency exhibiting resonant frequency of 2.97 GHz and Q factor of 278.

  10. Fatty acids modulate transforming growth factor-  activity and plasma clearance

    Microsoft Academic Search

    Thai-Yen Ling; Yen-Hua Huang; Ming-Chih Lai; Shuan Shian Huang; Jung San

    2003-01-01

    The activity and plasma clearance of transforming growth factor (TGF)-? are known to be regulated by activated ?2-macroglobulin (?2M*). This has been implicated in pathophysiological processes, but no small molecule compounds have been reported to modulate TGF-? activity by affecting the interaction of TGF-? and ?2M*. Here, we demonstrate that fatty acids are capable of inhibiting complex formation of TGF-?

  11. 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.

  12. Picolinic and isonicotinic acids: a Fourier transform microwave spectroscopy study.

    PubMed

    Peña, Isabel; Varela, Marcelino; Franco, Vanina G; López, Juan C; Cabezas, Carlos; Alonso, José L

    2014-12-01

    The rotational spectra of laser ablated picolinic and isonicotinic acids have been studied using broadband chirped pulse (CP-FTMW) and narrowband molecular beam (MB-FTMW) Fourier transform microwave spectroscopies. Two conformers of picolinic acid, s-cis-I and s-cis-II, and one conformer of isonicotinic acid have been identified through the analysis of their rotational spectra. The values of the inertial defect and the quadrupole coupling constants obtained for the most stable s-cis-I conformer of picolinic acid, evidence the formation of an O-H···N hydrogen bond between the acid group and the endocyclic N atom. The stabilization provided by this hydrogen bond compensates the destabilization energy due to the adoption of a -COOH trans configuration in this conformer. Its rs structure has been derived from the rotational spectra of several (13)C, (15)N, and (18)O species observed in their natural abundances. Mesomeric effects have been revealed by comparing the experimental values of the (14)N nuclear quadrupole coupling constants in the isomeric series of picolinic, isonicotinic, and nicotinic acids. PMID:25382020

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

    SciTech Connect

    Gullikson, Kevin; Kraus, Adam [Department of Astronomy, University of Texas, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); Dodson-Robinson, Sarah [Department of Physics and Astronomy, 217 Sharp Lab, Newark, DE 19716 (United States)

    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. Monomethylarsonous acid induces transformation of human bladder cells

    SciTech Connect

    Bredfeldt, Tiffany G. [Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 E. Mabel St., Tucson, AZ 85721 (United States); Jagadish, Bhumasamudram [Department of Chemistry, University of Arizona, Tucson, AZ 85721 (United States); Eblin, Kylee E. [Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 E. Mabel St., Tucson, AZ 85721 (United States); Mash, Eugene A. [Department of Chemistry, University of Arizona, Tucson, AZ 85721 (United States); Gandolfi, A. Jay [Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 E. Mabel St., Tucson, AZ 85721 (United States)]. 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.

  15. Transformation of ginseng saponins to ginsenoside rh 2 by acids and human intestinal bacteria and biological activities of their transformants

    Microsoft Academic Search

    Eun-Ah Bae; Myung Joo Han; Eun-Jin Kim; Dong-Hyun Kim

    2004-01-01

    When ginseng water extract was incubated at 60°C in acidic conditions, its protopanaxadiol ginsenosides were transformed to\\u000a ginsenoside Rg3 and ?20-ginsenoside Rg3. However, protopanaxadiol glycoside ginsenosides Rb1, Rb2 and Rc isolated from ginseng were mostly not transformed to ginsenoside Rg3 by the incubation in neutral condition. The transformation of these ginsenosides to ginsenoside Rg3 and ?20-ginsenoside Rg3 was increased by

  16. Cell surface-located deoxyribonucleic acid receptors in transformable pneumococci.

    PubMed Central

    Seto, H; Lopez, R; Tomasz, A

    1975-01-01

    We studied deoxyribonucleic acid (DNA) binding in transformable pneumococci. The relevant findings are as follows. (i) At least half of the DNA Molecules adsorbed to competent cells in the growth medium are attached to sites on the protoplast membrane. (ii) Most of the DNA bound to live competent cells in the presence of glucose is not released by moderate shear or by autolysin treatment. In contrast, most of the DNA adsorbed to competent cells in the absence of glucose is shear and autolysin sensitive. (iii) The presence of binding sites resembling in properties the sites in live competent cells can be demonstrated in wall-membrane complexes. Most of these sites are lost during preparation of cell walls and protoplasts. It is suggested that the DNA-binding site is a membrane component (protein?) Stabilized by polysaccharide (cell Wall) material. (IV) Mechanical or enzymatic damage to the cell wall or change in the ionic conditions can induce DNA binding (and surface-nuclease activity) in the incompetent pneumococci. However, such cells still show neither genetic transformation nor extensive nuclease-resistant binding of DNA. It is suggested that both competent and incompetent cells contain a large number of sequestered DNA-binding sites that can be unmasked by several experimental conditions. Induction of the competent state by the competence activator protein may involve an endogenous unmasking process. Images PMID:238945

  17. High efficiency transformation of intact yeast cells using single stranded nucleic acids as a carrier

    Microsoft Academic Search

    Robert H. Schiestl; R. Daniel Gietz

    1989-01-01

    A method, using LiAc to yield competent cells, is described that increased the efficiency of genetic transformation of intact cells of Saccharomyces cerevisiae to more than 1 × 105 transformants per microgram of vector DNA and to 1.5% transformants per viable cell. The use of single stranded, or heat denaturated double stranded, nucleic acids as carrier resulted in about a

  18. Specific Inhibitory Action of Polyunsaturated Fatty Acids on Lymphocyte Transformation Induced by PHA and PPD

    Microsoft Academic Search

    J. Mertin; D. Hughes

    1975-01-01

    Both saturated (SFA) and unsaturated fatty acids (UFS) inhibited PHA- and PPD-induced lymphocyte transformation. The degree of inhibition varied with the nature of the fatty acid (FA) and further comparison with their effect on unstimulated lymphocyte cultures suggests a specific action of polyunsaturated fatty acid (PUFA) on the lymphocyte PHA- and -PPD interaction. These findings are briefly discussed in the

  19. Transformation of ginseng saponins to ginsenoside Rh2 by acids and human intestinal bacteria and biological activities of their transformants.

    PubMed

    Bae, Eun-Ah; Han, Myung Joo; Kim, Eun-Jin; Kim, Dong-Hyun

    2004-01-01

    When ginseng water extract was incubated at 60 degrees C in acidic conditions, its protopanaxadiol ginsenosides were transformed to ginsenoside Rg3 and delta20-ginsenoside Rg3. However, protopanaxadiol glycoside ginsenosides Rb1, Rb2 and Rc isolated from ginseng were mostly not transformed to ginsenoside Rg3 by the incubation in neutral condition. The transformation of these ginsenosides to ginsenoside Rg3 and delta20-ginsenoside Rg3 was increased by increasing incubation temperature and time in acidic condition: the optimal incubation time and temperature for this transformation was 5 h and 60 degrees C resepectively. The transformed ginsenoside Rg3 and delta20-ginsenoside Rg3 were metabolized to ginsenoside Rh2 and delta20-ginsenoside Rh2, respectively, by human fecal microflora. Among the bacteria isolated from human fecal microflora, Bacteroides sp., Bifidobacterium sp. and Fusobacterium sp. potently transformed ginsenoside Rg3 to ginsenoside Rh2. Acid-treated ginseng (AG) extract, fermented AG extract, ginsenoside Rh2 and protopanaxadiol showed potent cytotoxicity against tumor cell lines. AG extract, fermented AG extract and protopanaxadiol potently inhibited the growth of Helicobacter pylori. PMID:14969341

  20. Prostaglandin Endoperoxides. Novel Transformations of Arachidonic Acid in Human Platelets

    Microsoft Academic Search

    Mats Hamberg; Bengt Samuelsson

    1974-01-01

    Arachidonic acid incubated with human platelets was converted into three compounds, 12L-hydroxy-5,8,10,14-eicosatetraenoic acid, 12L-hydroxy-5,8,-10-heptadecatrienoic acid, and the hemiacetal derivative of 8-(1-hydroxy-3-oxopropyl)-9,12L-dihydroxy-5,10-heptadecadienoic acid. The formation of the two latter compounds from arachidonic acid proceeded by pathways involving the enzyme, fatty acid cyclo-oxygenase, in the initial step and with the prostaglandin endoperoxide, PGG2, as an intermediate. The first mentioned compound was formed

  1. 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

  2. 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.

  3. Studies of Telluric Co\\/ from Mauna-Kea Using the James-Clerk Telescope

    Microsoft Academic Search

    K. E. Preston; P. A. Feldman; D. L. Singleton; T. Amano; H. E. Matthews; A. Kudo

    1993-01-01

    Measurement of the J =3 --> 2 rotational transition of telluric CO is reported for the first time, along with the first quasi-simultaneous measurement of the J =2 --> 1 transition, using the James Clerk Maxwell Telescope at Mauna Kea, Hawaii. The line shape of the observed J= 3 --> 2 transition is in good agreement with a modelled line

  4. Modified zirconia solid acid catalysts for organic synthesis and transformations

    Microsoft Academic Search

    Benjaram M. Reddy; Pavani M. Sreekanth; Vangala R. Reddy

    2005-01-01

    A series of sulfate, molybdate and tungstate promoted ZrO2 catalysts were prepared by wet impregnation method. To incorporate these promoters to Zr(OH)4, sulfuric acid, ammonium heptamolybdate, and ammonium metatungstate were used as precursors, respectively. Further, a Pt promoted Mo-ZrO2 catalyst was also prepared separately by impregnating with hexachloroplatinic acid. The surface and bulk properties of various promoted ZrO2 catalysts were

  5. Transformation of chenodeoxycholic acid to ursodeoxycholic acid in patients with Crohn's disease

    SciTech Connect

    Miwa, H.; Yamamoto, M.; Nishida, T.; Yao, T.

    1986-03-01

    In vivo 7 beta-epimerization of chenodeoxycholic acid to ursodeoxycholic acid and the role of 7-ketolithocholic acid as an intermediate in this biotransformation were studied in 11 patients with Crohn's disease and in 5 healthy volunteers. The incorporation of deuterium into biliary ursodeoxycholic acid and 7-ketolithocholic acid was determined by computed gas chromatography-mass fragmentography after ingestion of a dideuterated chenodeoxycholic acid, chenodeoxycholic-11,12-d2 acid. The incorporation of deuterium into ursodeoxycholic acid increased to a peak level at 48 h in the patients with Crohn's disease, but was delayed in healthy volunteers. In 8 patients and 2 healthy controls there were small amounts of 7-ketolithocholic acid in bile. The incorporation of deuterium into 7-ketolithocholic acid was confirmed in only 2 patients and the peak level was noted at 48 h. These observations suggest that 7-ketolithocholic acid is an intermediate of this biotransformation in patients with Crohn's disease.

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

    NASA Astrophysics Data System (ADS)

    Tefelski, D. B.; Siegoczy?ski, R. M.; Rostocki, A. J.; Kos, A.; Ko?ciesza, 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.

  7. Main fatty acid classes in vegetable oils by SB-ATR-Fourier transform infrared (FTIR) spectroscopy

    Microsoft Academic Search

    S. T. H. Sherazi; M. Younis Talpur; S. A. Mahesar; Aftab A. Kandhro; Sarfraz Arain

    2009-01-01

    The prospect of using single bounce attenuated total reflectance (SB-ATR)-Fourier transform infrared (FTIR) spectroscopy as a rapid quantitative tool to determine the main fatty acid groups present in different edible oils was investigated. Partial least squares (PLS) calibrations were developed using SB-ATR-FTIR spectra which were associated with fatty acid groups (saturated, trans, mono- and polyunsaturated) using quantitative data obtained by

  8. Transformation of arachidonic acid to 19-hydroxy- and 20-hydroxy-eicosatetraenoic acids using Candida bombicola

    Microsoft Academic Search

    Asmita Prabhune; Simon R. Fox; Colin Ratledge

    2002-01-01

    Candida bombicola (ATCC 22214) and C. apicola (ATCC 96134), grown on glucose (100 g l-1) and arachidonic acid (5Z, 8Z, 11Z, 14Z-eicosatetraenoic acid; AA), 1.25 g l-1, synthesized sophorolipid up to 0.93 g l-1. Acid hydrolysis of sophorolipid yielded 19-hydroxy-5Z, 8Z, 11Z, 14Z-eicosatetraenoic acid (19-HETE) and 20-hydroxy-5Z, 8Z, 11Z, 14Z-eicosatetraenoic acid (20-HETE) which were identified by TLC and GC-MS; the

  9. Conjugated Linoleic Acid Accumulation via 10Hydroxy12-Octadecaenoic Acid during Microaerobic Transformation of Linoleic Acid by Lactobacillus acidophilus

    Microsoft Academic Search

    JUN OGAWA; KENJI MATSUMURA; SHIGENOBU KISHINO; YORIKO OMURA; SAKAYU SHIMIZU

    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

  10. 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...

  11. Monitoring the sorption of propanoic acid by montmorillonite using Diffuse Reflectance Fourier Transform Infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Parker, R. W.; Frost, R. L.

    1998-06-01

    This paper describes how Diffuse Reflectance Fourier Transform Infrared (DRIFT) spectroscopy was used to monitor the sorption behavior of a short chain fatty acid, propanoic acid, on the clay mineral, montmorillonite. Organic acids bind to montmorillonite in two ways, either by dipole interaction with the oxygens in the interlayer space, or by bonding of the carboxylate anions to exposed aluminum ions. The DRIFT spectra of propanoic acid-montmorillonite complexes have bands at 1728 and 1554 cm-1, which are attributed to the symmetric, and antisymmetric stretching vibrations, respectively, of the C=O, ?(C=O)s, and O-C-O, ?(O-C-O)a, bonds of the carboxylic acid group. Each band represents one of the two different binding modes. These bands can be used to monitor the physical and chemical adsorption of the acid by the montmorillonite. When the peak area of each vibration is plotted against increasing acid concentration, both increase to a maximum. However the peak area for the ?(O-C-O)a vibration reaches a maximum at a much lower acid concentration than the ?(O=O)s vibration. The former maximum corresponds to saturation of the available binding sites on the edge surface aluminum ions. This concentration can be used to calculate the number of binding sites on the clay crystal. Where propanoic acid is allowed to diffuse from the clay, the bound fraction remains on the montmorillonite reducing the available acid that can be desorbed or leached from the clay.

  12. The Production of 10-Hydroxystearic and 10-Ketostearic Acids Is an Alternative Route of Oleic Acid Transformation by the Ruminal Microbiota

    Microsoft Academic Search

    Thomas C. Jenkins; Amer A. AbuGhazaleh; Sharon Freeman; Evanne J. Thies

    The formation of hydroxystearic acid (HSA) and ketostearic acid (KSA) from oleic acid transformation has been documented in a variety of microbial species, including several isolated from the rumen of domesticated ruminant species. However, their ruminal production rates have not been established as influenced by fatty acid source. Dosing continuous cultures of mixed ruminal microorganisms with 1-13C-oleic acid increased the

  13. Functional transformations of bile acid transporters induced by high-affinity macromolecules.

    PubMed

    Al-Hilal, Taslim A; Chung, Seung Woo; Alam, Farzana; Park, Jooho; Lee, Kyung Eun; Jeon, Hyesung; Kim, Kwangmeyung; Kwon, Ick Chan; Kim, In-San; Kim, Sang Yoon; Byun, Youngro

    2014-01-01

    Apical sodium-dependent bile acid transporters (ASBT) are the intestinal transporters that form intermediate complexes with substrates and its conformational change drives the movement of substrates across the cell membrane. However, membrane-based intestinal transporters are confined to the transport of only small molecular substrates. Here, we propose a new strategy that uses high-affinity binding macromolecular substrates to functionally transform the membrane transporters so that they behave like receptors, ultimately allowing the apical-basal transport of bound macromolecules. Bile acid based macromolecular substrates were synthesized and allowed to interact with ASBT. ASBT/macromolecular substrate complexes were rapidly internalized in vesicles, localized in early endosomes, dissociated and escaped the vesicular transport while binding of cytoplasmic ileal bile acid binding proteins cause exocytosis of macromolecules and prevented entry into lysosomes. This newly found transformation process of ASBT suggests a new transport mechanism that could aid in further utilization of ASBT to mediate oral macromolecular drug delivery. PMID:24566561

  14. Novel biological transformations of 15-Ls-hydroperoxy-5,8,11,13-eicosatetraenoic acid.

    PubMed

    Hamberg, M; Herman, C A; Herman, R P

    1986-07-18

    [1-14C]Arachidonic acid was incubated with homogenates of the fungus, Saprolegnia parasitica. The products consisted of comparable amounts of two epoxy alcohols, 15-Ls-hydroxy-11,12-epoxy-5cis,8cis,13trans- eicosatrienoic acid and 15-hydroxy-13,14-epoxy-5cis,8cis,11cis-eicosatrienoic acid. Results of incubations carried out in the presence of nordihydroguaiaretic acid, 5,8,11,14-eicosatetraynoic acid, p-hydroxymercuribenzoate as well as glutathione peroxidase plus reduced glutathione demonstrated that transformation of arachidonic acid into epoxy alcohols occurred with the formation of 15-Ls-hydroperoxy-5cis,8cis,11cis,13trans- eicosatetraenoic acid (15-HPETE) as an intermediate. The pathway involved a lipoxygenase catalyzing the oxygenation of arachidonic acid at the 15L position to produce 15-HPETE, and a hydroperoxide isomerase activity which catalyzed conversion of 15-HPETE into the two epoxy alcohols. Studies with 15-[18O2]HPETE demonstrated that both oxygens of 15-HPETE were retained in the epoxy alcohols. Furthermore, experiments with mixtures of 15-[18O2]-and 15-[16O2]HPETE showed that conversion of 15-HPETE into epoxy alcohols occurred by an intramolecular transfer of hydroperoxide oxygen. PMID:3089290

  15. Effect of growth rate and nutrient limitation on the transformability of Escherichia coli with plasmid deoxyribonucleic acid.

    PubMed Central

    Jones, I M; Primrose, S B; Robinson, A; Ellwood, D C

    1981-01-01

    The observed transformation frequency by plasmid deoxyribonucleic acid of Escherichia coli grown in continuous culture was found to depend on both the steady-state growth rate and the type of nutrient used to limit growth. With carbon, nitrogen, or phosphorus limitation, the faster the growth rate, the higher the transformation frequency. The increase in transformation frequency associated with higher rates was shown to be due to more transformable cells in the population rather than an increased efficiency of deoxyribonucleic acid uptake. Growth rate had relatively little effect on the transformability of cells from sulfate- and Mg2+-limited chemostats, indicating that some factor other than the growth rate must influence the frequency of transformation. Regardless of the nutrient limitation or the growth rate, no transformants were obtained in the absence of CaCl2. PMID:7016833

  16. Molecfit: A general tool for telluric absorption correction II. Quantitative evaluation on ESO-VLT X-Shooter spectra

    E-print Network

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

    2015-01-01

    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...

  17. Evidence of metabolic transformations of amino acids into higher alcohols through (13)C NMR studies of wine alcoholic fermentation.

    PubMed

    López-Rituerto, Eva; Avenoza, Alberto; Busto, Jesús H; Peregrina, Jesús M

    2010-04-28

    Because the metabolite transformations in wine fermentation processes play a crucial role in the organoleptic and hygienic quality of wines, the nuclear magnetic resonance (NMR) technique is presented as a significant tool to follow metabolic pathways. In this paper, we investigated the transformation of several amino acids into their corresponding higher alcohols during the alcoholic fermentation, showing that the amino acids are totally consumed in the first stages of the process. PMID:20369806

  18. Ge2Sb2Te5 Film Fabrication by Tellurization of Chemical Vapor Deposited GeSb

    NASA Astrophysics Data System (ADS)

    Suda, Kohei; Uno, Tomohiro; Miyakawa, Tatsuya; Sawamoto, Naomi; Machida, Hideaki; Ishikawa, Masato; Sudoh, Hiroshi; Ohshita, Yoshio; Ogura, Atsushi

    2013-12-01

    This paper describes stoichiometric Ge2Sb2Te5 (GST) film fabrication by the process based on chemical vapor deposition (CVD). GST films were fabricated by tellurization after GeSb CVD. This two step process enabled to fill high aspect holes. By applying appropriate precursors and process temperature, the surface morphology of the GST film was significantly improved. The moderate tellurization reaction process might contribute GST formation with maintaining the amorphous structure of the CVD GeSb. We believe this technique is useful for phase change memory application.

  19. Mammalian cell transformation induced by chromium(VI) compounds in the presence of nitrilotriacetic acid

    SciTech Connect

    Lanfranchi, G.; Paglialunga, S.; Levis, A.G.

    1988-01-01

    The authors used a soft agar assay on cultured Syrian hamster fibroblasts to determined the ability of nitrilotriacetic acid (NTA) and Cr(VI) compounds to induce malignant cell transformation. Induction of extended anchorage-independent growth was detected in BHK 21/c13 cells by scoring colonies of transformed cells visible to the naked eye 20-25 d after plating in growth medium containing agar. Survival was determined by plating cells in liquid medium without agar and by counting the number of macroscopic colonies after 7-10 d. Mitomycin C and 4-nitroquinoline 1-oxide were used as reference direct transforming agents, with clearly positive results. In their hands no increase of the spontaneous transformation rate of BHK cells was induced by NTA concentrations ranging from 2 x 10/sup -3/ to 10/sup -2/M, although the survival index was significantly reduced above 4 x 10/sup -3/M NTA. Two Cr(VI) compounds, K/sub 2/Cr/sub 2/O/sub 7/, which is highly soluble in water, and CaCrO/sub 4/, which is partially soluble, were tested in the soft agar assay either in the absence or in the presence of NTA. When used alone, both compounds behaved as positive transforming agents. NTA increased 4 or 10 times the cytotoxicity and the transforming activity of CaCrO/sub 4/ and K/sub 2/Cr/sub 2/O/sub 7/, respectively. As the amounts of soluble Cr(VI) detectable in the K/sub 2/Cr/sub 2/O/sub 7/ and CaCrO/sub 4/ solutions were not increased in the presence of NTA, a synergistic interaction NTA and soluble Cr(VI) is inferred.

  20. 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.

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

    SciTech Connect

    Huang, Lianjie [Los Alamos National Laboratory; Albrecht, Michael [LOS ALAMOS GEOTHERMAL

    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. Perfluorobutyric Acid and its Monohydrate: a Chirped Pulse and Cavity Based Fourier Transform Microwave Spectroscopic Study

    NASA Astrophysics Data System (ADS)

    Thomas, Javix; Serrato, Agapito, III; Lin, Wei; Jaeger, Wolfgang; Xu, Yunjie

    2014-06-01

    Perfluorobutyric acid (PFBA) is highly soluble in water and is a molecule of environmental importance. Rotational spectra of PFBA and its monohydrate were studied using a broadband chirped pulse and a narrow band cavity based Fourier transform microwave spectrometers and high level ab initio calculations. Extensive conformational search was 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 for PFBA and its monohydrate, respectively. One set of rotational transitions of PFBA and its mono-hydrate in each case was observed and assigned. Based on the broadband spectra obtained, one can confidently conclude that only one dominate conformer exists in each case. The orientation of the hydroxyl group in PFBA was determined using isotopic analysis. Comparison of the observed transition intensities and the calculated electric dipole moment components allowed one to identify the most stable monohydrate conformation which takes on the insertion hydrogen-bonding topology. Comparison to the shorter chain analogues, i.e. trifluoroacetic acid, perfluoropropionic acid, and their monohydrates, was made to elucidate the general trend in their conformational preference and binding topologies.

  3. Attenuated total reflectance Fourier-transform infrared spectroscopy of carboxylic acids adsorbed onto mineral surfaces

    NASA Astrophysics Data System (ADS)

    Kubicki, J. D.; Schroeter, L. M.; Itoh, M. J.; Nguyen, B. N.; Apitz, S. E.

    1999-09-01

    A suite of naturally-occurring carboxylic acids (acetic, oxalic, citric, benzoic, salicylic and phthalic) and their corresponding sodium salts were adsorbed onto a set of common mineral substrates (quartz, albite, illite, kaolinite and montmorillonite) in batch slurry experiments. Solution pH's of approximately 3 and 6 were used to examine the effects of pH on sorption mechanisms. Attenuated total reflectance Fourier-transform infrared (ATR FTIR) spectroscopy was employed to obtain vibrational frequencies of the organic ligands on the mineral surfaces and in solution. UV/visible spectroscopy on supernatant solutions was also employed to confirm that adsorption from solution had taken place for benzoic, salicylic and phthalic acids. Molecular orbital calculations were used to model possible surface complexes and interpret the experimental spectra. In general, the tectosilicates, quartz and albite feldspar, did not chemisorb (i.e., strong, inner-sphere adsorption) the carboxylate anions in sufficient amounts to produce infrared spectra of the organics after rinsing in distilled water. The clays (illite, kaolinite and montmorillonite) each exhibited similar ATR FTIR spectra. However, the illite sample used in this study reacted to form strong surface and aqueous complexes with salicylic acid before being treated to remove free Fe-hydroxides. Chemisorption of carboxylic acids onto clays is shown to be limited without the presence of Fe-hydroxides within the clay matrix.

  4. Transformation of the fungicide cyprodinil by a laccase of Trametes villosa in the presence of phenolic mediators and humic acid.

    PubMed

    Kang, Ki-Hoon; Dec, Jerzy; Park, Heekyung; Bollag, Jean-Marc

    2002-11-01

    Xenobiotic chemicals can be transformed or covalently bound to humic materials by oxidoreductive enzymes present in terrestrial systems. Chemicals that are not substrates for oxidoreductive enzymes may undergo transformation in the presence of certain reactive compounds, which are often referred to as mediators. In this study, cyprodinil, a broad-spectrum fungicide, did not show any transformation when incubated alone with a laccase from Trametes villosa. It was transformed to a significant extent, however, when a mediator was present. All of the 13 tested mediators belonged to the group of naturally occurring phenols. With some exceptions (2,6-dimethoxyphenol, syringic acid, and ferulic acid), phenols substituted with one or two methoxy groups were very effective mediators. In experiments with 14C-labeled cyprodinil, the radioactive label was largely associated with brown transformation products that precipitated out of the aqueous solution. As determined by mass spectrometry, the products were mixed oligomers resulting from cross-coupling between cyprodinil and a mediator. The addition of large amounts of humic acid (HA) (400 mg/L) to the reaction mixtures involving the most effective mediators reduced cyprodinil transformation (42.6-68.6%) by 12-48%, probably due to an inhibitory effect. The inhibition decreased with decreasing concentration of HA. The addition of HA (400 mg/L) to the reaction mixtures involving the least effective mediators or no mediators (control) enhanced cyprodinil transformation (0.3-17.6%) by 2.9-17.1%, probably as a result of binding to HA. PMID:12448535

  5. Transformers

    NSDL National Science Digital Library

    Kuphaldt, Tony R.

    All About Circuits is a website that â??provides a series of online textbooks covering electricity and electronics.â? Written by Tony R. Kuphaldt, the textbooks available here are wonderful resources for students, teachers, and anyone who is interested in learning more about electronics. This specific section, Transformers, is the ninth chapter in Volume II â??Alternating Current (AC). A few of the topics covered in this chapter include: Mutual inductance and basic operation; Step-up and Step-down transformers; Electrical isolation; Phasing; Winding configurations; Voltage Regulation; and finally, Special transformers and applications.. Diagrams and detailed descriptions of concepts are included throughout the chapter to provide users with a comprehensive lesson. Visitors to the site are also encouraged to discuss concepts and topics using the All About Circuits discussion forums (registration with the site is required to post materials).

  6. 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 25°C to 10°C, 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 15°C 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

  7. All trans-retinoic acid (ATRA) induces re-differentiation of early transformed breast epithelial cells

    PubMed Central

    ARISI, MARIA F.; STARKER, REBECCA A.; ADDYA, SANKAR; HUANG, YONG; FERNANDEZ, SANDRA V.

    2014-01-01

    Retinoids have been used as potential chemotherapeutic or chemopreventive agents because of their differentiative, anti-proliferative, pro-apoptotic and antioxidant properties. We investigated the effect of all trans-retinoic acid (ATRA) at different stages of the neoplastic transformation using an in vitro model of breast cancer progression. This model was previously developed by treating the MCF-10F human normal breast epithelial cells with high dose of estradiol and consists of four cell lines which show a progressive neoplastic transformation: MCF-10F, normal stage; trMCF, transformed MCF-10F; bsMCF, invasive stage; and caMCF, tumorigenic stage. In 3D cultures, MCF-10F cells form tubules resembling the structures in the normal mammary gland. After treatment with estradiol, these cells formed tubules and spherical masses which are indicative of transformation. Cells that only formed spherical masses in collagen were isolated (trMCF clone 11) and treated with ATRA. After treatment with 10 or 1 ?M ATRA, the trMCF clone 11 cells showed tubules in collagen; 10 and 43% of the structures were tubules in cells treated with 10 and 1 ?M ATRA, respectively. Gene expression studies showed that 207 genes upregulated in transformed trMCF clone 11 cells were downregulated after 1 ?M ATRA treatment to levels comparable to those found in the normal breast epithelial cells MCF-10F. Furthermore, 236 genes that were downregulated in trMCF clone 11 were upregulated after 1 ?M ATRA treatment to similar levels shown in normal epithelial cells. These 443 genes defined a signature of the ATRA re-programming effect. Our results showed that 1 ?M ATRA was able to re-differentiate transformed cells at early stages of the neoplastic process and antagonistically regulate breast cancer associated genes. The invasive and tumorigenic cells did not show any changes in morphology after ATRA treatment. These results suggest that ATRA could be used as a chemopreventive agent to inhibit the progression of premalignant lesions of the breast. PMID:24676586

  8. 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, Bjørg; Jørgensen, Kjetil; Lien, Sigbjørn; 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

  9. 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 [Collaboratory for Advanced Computing and Simulations, Department of Physics and Astronomy, Department of Computer Science, Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, California 90089-0242 (United States)

    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.

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

    PubMed

    Dušek, Martin; Olšovská, Jana; Krofta, Karel; Jurková, Marie; Mikyška, 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 Sládek 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

  11. An attempt to channel the transformation of vanillic acid into vanillin by controlling methoxyhydroquinone formation in Pycnoporus cinnabarinus with cellobiose

    Microsoft Academic Search

    L. Lesage-Meessen; M. Haon; M. Delattre; J.-F. Thibault; B. Colonna Ceccaldi; M. Asther

    1997-01-01

    The effects of adding cellobiose on the transformation of vanillic acid to vanillin by two strains of Pycnoporus cinnabarinus MUCL39532 and MUCL38467 were studied. When maltose was used as the carbon source in the culture medium, very high levels\\u000a of methoxyhydroquinone were formed from vanillic acid. When cellobiose was used as the carbon source and\\/or added to the culture\\u000a medium

  12. Identification and RP-HPLC-ESI-MS/MS quantitation of bitter-tasting beta-acid transformation products in beer.

    PubMed

    Haseleu, Gesa; Intelmann, Daniel; Hofmann, Thomas

    2009-08-26

    Thermal treatment of the hop beta-acid colupulone under wort boiling conditions, followed by LC-TOF-MS and 1D/2D NMR spectroscopy, revealed cohulupone, hulupinic acid, nortricyclocolupone, two tricyclocolupone epimers, two dehydrotricyclocolupone epimers, two hydroxytricyclocolupone epimers, and two hydroperoxytricyclocolupone epimers as the major bitter-tasting beta-acid transformation products. Among these compounds, the chemical structures of the hydroxy- as well as the hydroperoxytricyclocolupone epimers have not previously been confirmed by 1D/2D NMR experiments. Depending on their chemical structure, these compounds showed rather low recognition thresholds ranging from 7.9 to 90.3 micromol/L. The lowest thresholds of 7.9 and 14.7 micromol/L were found for cohulupone, imparting a short-lasting, iso-alpha-acid-like bitter impression, and for hydroxytricyclocolupone, exhibiting a long-lasting, lingering, and harsh bitterness perceived on the posterior tongue and throat. Furthermore, HPLC-ESI-MS/MS analysis allowed for the first time a simultaneous detection and quantitation of these bitter-tasting beta-acid transformation products in a range of commercial beer samples without any sample cleanup. Depending on the type of beer, these studies revealed remarkable differences in the concentrations of the individual beta-acid transformation products. PMID:19627140

  13. Low-temperature phase transformation studies in the stearic acid: C form.

    PubMed

    de Sousa, F F; Freire, P T C; de Menezes, A S; Pinheiro, G S; Cardoso, L P; Alcantara, P; Moreira, S G C; Melo, F E A; Mendes Filho, J; Saraiva, G D

    2015-09-01

    This paper reports the temperature-dependent measurements in the C form of stearic acid. Raman scattering, X-ray diffraction, and differential scanning calorimetry measurements were performed at low temperatures. The polarized Raman spectra were measured for temperatures ranging from 8 to 300K over the spectral range of 30-3000cm(-1). The spectral changes observed in both the lattice vibrational modes and the internal vibrational modes regions of the Raman spectrum, allowed to identify a phase transition undergone by the stearic acid crystal occurring between 210 and 170K and a change in the structure continues to be observed down to 8K. The anharmonicity of some vibrational modes and the possible space groups presented by the crystal at low temperatures were also discussed. Low-temperature X-ray diffraction measurements were performed from 290 to 80K and the results showed slight changes in the lattice parameters at ?200K. Furthermore, the evidence of the phase transformation was provided by the differential scanning calorimetry measurements, which identified an enthalpic anomaly at about 160K. PMID:25909902

  14. Docosahexaenoic acid attenuates hyperglycemia-enhanced hemorrhagic transformation after transient focal cerebral ischemia in rats.

    PubMed

    Lin, Y; Xu, M; Wan, J; Wen, S; Sun, J; Zhao, H; Lou, M

    2015-08-20

    Hemorrhagic transformation (HT) is a feared complication of cerebral ischemic infarction, especially following the use of thrombolytic therapy. In this study, we examined whether docosahexaenoic acid (DHA; 22:6n-3), an omega-3 essential fatty acid family member, can protect the brain from injury and whether DHA can decrease the risk of HT enhanced by hyperglycemia after focal ischemic injury. Male Sprague-Dawley rats were injected with 50% dextrose (6ml/kg intraperitoneally) to induce hyperglycemia 10min before 1.5h of filament middle cerebral artery occlusion (MCAO) was performed. Treatment with DHA (10mg/kg) 5min before reperfusion reduced HT and further improved the 7-day neurological outcome. It also reduced infarct volume, which is consistent with the restricted DWI and T2WI hyperintensive area. Reduced Evans Blue extravasation and increased expression of collagen IV indicated the improved integrity of the blood-brain barrier (BBB) in DHA-treated rats. Moreover, DHA reduced the expression of the intercellular adhesion molecule-1 (ICAM-1) in the ischemic injured brain. Therefore, we conclude that DHA attenuated hyperglycemia-enhanced HT and improved neurological function by preserving the integrity of BBB and reducing inflammation. PMID:26102005

  15. 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.

  16. Reduced Oil Accumulation in Cottonseeds Transformed with a Brassica Nonfunctional Allele of a Delta12 Fatty Acid Desaturase (FAD2)

    Microsoft Academic Search

    Kent D. Chapman; Purnima B. Neogi; Kater D. Hake; Agnes A. Stawska; Thomas R. Speed; Matthew Q. Cotter; David C. Garrett; Thomas Kerby; Charlene D. Richardson; Brian G. Ayre; Supriyo Ghosh; Anthony J. Kinney

    2008-01-01

    In an effort to better understand the mechanisms that regulate oil accumulation and packaging in seeds, transgenic cotton lines were generated using a Brassica napus nonfunctional delta-12 fatty acid desaturase (FAD2) gene under control of the phaseolin promoter. Seeds of numerous transgenic plant lines had reduced oil content compared with null-segregating siblings or non- transformed seeds. Seed oil content was

  17. Enhancement of the reductive transformation of pentachlorophenol by polycarboxylic acids at the iron oxide-water interface.

    PubMed

    Li, Fangbai; Wang, Xugang; Li, Yongtao; Liu, Chengshuai; Zeng, Fang; Zhang, Lijia; Hao, Mingde; Ruan, Huada

    2008-05-15

    The enhancement effect of polycarboxylic acids on reductive dechlorination transformation of pentachlorophenol (PCP) reacting with iron oxides was studied in anoxic suspension. Batch experiments were performed with three species of iron oxides (goethite, lepidocrocite and hematite) and four species of polycarboxylic acids (oxalate, citrate, succinate, and tartrate) through anoxic abiotic reactors. The chemical analyses and morphological observation from scanning and transmission electron microscopy showed that different combinations between polycarboxylic acids and iron oxides produced distinct contents of Fe(II)-polycarboxylic ligand complexes, which significantly enhanced PCP transformation. Generation of the surface-bound Fe(II) depended on concentration of polycarboxylic acids. The optimal concentration for the enhancement was 2.0 mM oxalic acid. The dechlorination mechanism was further demonstrated by generation of chloride ions. The results suggest that surface-bound Fe(II) formed on the iron oxides surface appears to be a key factor in enhancing PCP transformation, and the mole ratio of oxalate to surface-bound Fe(II) (oxalate/Fe(II)) acted as an indicator of the enhancement effect. The enhancement mechanism attributes to strong nucleophilic ability and low reductive potential of the equivalent Fe(II)-polycarboxylate complexes. Therefore, the enhancement effects might be helpful for understanding the natural attenuation of reducible organic pollutants at the interface of contaminated soil in anoxic condition. PMID:18329661

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

    SciTech Connect

    Ktari, L. [Laboratoire de l'Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Abdelhedi, M. [Laboratoire de l'Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Laboratoire Leon Brouillon LLB, CEA Saclay, 91191 Gif-Sur-Yvette Cedex (France); Bouhlel, N. [Laboratoire de l'Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Dammak, M., E-mail: meddammak@yahoo.fr [Laboratoire de l'Etat Solide (LES), Faculte des Sciences de Sfax, 3000 Sfax (Tunisia); Cousson, A. [Laboratoire Leon Brouillon LLB, CEA Saclay, 91191 Gif-Sur-Yvette Cedex (France)

    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.

  19. Main fatty acid classes in vegetable oils by SB-ATR-Fourier transform infrared (FTIR) spectroscopy.

    PubMed

    Sherazi, S T H; Talpur, M Younis; Mahesar, S A; Kandhro, Aftab A; Arain, Sarfraz

    2009-12-15

    The prospect of using single bounce attenuated total reflectance (SB-ATR)-Fourier transform infrared (FTIR) spectroscopy as a rapid quantitative tool to determine the main fatty acid groups present in different edible oils was investigated. Partial least squares (PLS) calibrations were developed using SB-ATR-FTIR spectra which were associated with fatty acid groups (saturated, trans, mono- and polyunsaturated) using quantitative data obtained by gas chromatography (GC). Good calibrations were obtained for all main four fat groups (saturated, mono, trans and polyunsaturated) with excellent precision. The coefficient of determination (R(2)), root mean square error of prediction (RMSEP) and bias for validation set were obtained as 0.999, 2.43 and 0.998 for saturated; 0.999, 1.850 and 0.003 for mono; 0.999, 0.625 and -0.001 for trans while for poly the values were 0.999, 1.170 and 0.003, respectively. The results of 13 validation samples for total saturated, mono, trans and polyunsaturated fats by FI-IR were found in the range of 8.16-55.16, 37.62-74.75, 0.20-18.16 and 1.36-62.35%, respectively. The present study shows that it may well be possible to expand the utility of SB-ATR-FTIR spectroscopy not only to provide isolated trans data, but also serve as a simple, rapid and quantitative means of categorizing the main groups present in the edible oils. The information obtained would be useful for meeting the new lipid nutritional labeling requirements. PMID:19836526

  20. Myocardial contraction and hyaluronic acid mechanotransduction in epithelial-to-mesenchymal transformation of endocardial cells.

    PubMed

    Sewell-Loftin, Mary Kathryn; DeLaughter, Daniel M; Peacock, Jon R; Brown, Christopher B; Baldwin, H Scott; Barnett, Joey V; Merryman, W David

    2014-03-01

    Epithelial-to-mesenchymal transition (EMT) of endocardial cells is a critical initial step in the formation of heart valves. The collagen gel in vitro model has provided significant information on the role of growth factors regulating EMT but has not permitted investigation of mechanical factors. Therefore we sought to develop a system to probe the effects of mechanical inputs on endocardial EMT by incorporating hyaluronic acid (HA), the primary component of endocardial cushions in developing heart valves, into the gel assay. This was achieved using a combination collagen and crosslinkable methacrylated HA hydrogel (Coll-MeHA). Avian atrioventricular canal explants on Coll-MeHA gels showed increased numbers of transformed cells. Analysis of the mechanical properties of Coll-MeHA gels shows that stiffness does not directly affect EMT. Hydrogel deformation from the beating myocardium of explants directly led to higher levels of regional gel deformation and larger average strain magnitudes associated with invaded cells on Coll-MeHA gels. Inhibition of this contraction reduced EMT on all gel types, although to a lesser extent on Coll-MeHA gels. Using the system we have developed, which permits the manipulation of mechanical factors, we have demonstrated that active mechanical forces play a role in the regulation of endocardial EMT. PMID:24433835

  1. Transformation of 2,4-dichlorophenoxyacetic acid in four different marine and estuarine sediments: effects of sulfate, hydrogen and acetate on dehalogenation and side-chain cleavage

    Microsoft Academic Search

    Alfred W Boyle; Victoria K Knight; Max M Häggblom; Lily Y Young

    1999-01-01

    Enrichments initiated with marine and estuarine sediments from the Arthur Kill (NY\\/NJ estuary) and Paleta Creek (San Diego Bay, CA), transformed 2,4-dichlorophenoxyacetic acid to 4-chlorophenol in the presence of sulfate (25 mM). Transformation of 2,4-dichlorophenoxyacetic acid was not observed with two other marine sediments from Tuckerton, NJ and Flax Pond (Stony Brook, NY). The lag period prior to 2,4-dichlorophenoxyacetic acid

  2. 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

    2015-06-25

    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

  3. 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-NH 2/Gal-NH 2) 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-NH 2/Gal-NH 2 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.

  4. Determination of Sodium Fatty Acid in Soap Formulation Using Fourier Transform Infrared (FTIR) Spectroscopy and Multivariate Calibrations

    Microsoft Academic Search

    Abdul Rohman; Yaakob Bin Che Man

    2011-01-01

    Fourier Transform Infrared (FTIR) spectroscopy using an attenuated total reflectance (ATR) accessory has been investigated\\u000a as a method for the determination of sodium-fatty acid (sodium-FA) in soap formulations. Multivariate calibrations namely\\u000a partial least squares regression (PLS) and principle component regression (PCR) were developed for the prediction of sodium-FA\\u000a using spectral ranges on the basis of relevant IR absorption bands related

  5. Determination of 2,4-dichlorophenoxyacetic acid and its major transformation product in soil samples by liquid chromatographic analysis

    Microsoft Academic Search

    O. P. de Amarante; N. M. Brito; T. C. R. dos Santos; G. S. Nunes; M. L. Ribeiro

    2003-01-01

    The 2,4-dichlorophenoxyacetic acid (2,4-D) is one of the most applied herbicides around the world to control broad leave herbs in many crops. In this study, a method was developed for simultaneous extraction and determination of 2,4-D and its major transformation product, i.e., the 2,4-dichlorophenol (2,4-DCP), in soil samples. The herbicide and its degradation product were extracted twice from soil samples,

  6. Valproic acid overcomes transforming growth factor-?-mediated sorafenib resistance in hepatocellular carcinoma

    PubMed Central

    Matsuda, Yasunobu; Wakai, Toshifumi; Kubota, Masayuki; Osawa, Mami; Hirose, Yuki; Sakata, Jun; Kobayashi, Takashi; Fujimaki, Shun; Takamura, Masaaki; Yamagiwa, Satoshi; Aoyagi, Yutaka

    2014-01-01

    Sorafenib is a multi-kinase inhibitor approved for hepatocellular carcinoma, but rarely causes tumor regression in patients with chronic liver diseases. To investigate whether growth factor-mediated signaling is involved in sorafenib resistance, HepG2 and PLC/PRF/5 hepatoma cells were exposed to epidermal growth factor (EGF), hepatocyte growth factor (HGF) or transforming growth factor-? (TGF-?) prior to treatment with sorafenib. Furthermore, to identify an effective combination treatment with sorafenib, growth factor-sensitized cells were treated with sorafenib alone or in combination with celecoxib, lovastatin or valproic acid (VPA). Trypan blue staining and Annexin V assays showed that the cytotoxic effect of sorafenib was inhibited by 15-54% in cells sensitized to TGF-? (P<0.05). Western blotting analysis showed that TGF-? significantly activated extracellular signal-regulated kinase (ERK)-mediated AKT signaling, and sorafenib failed to suppress both ERK and AKT in TGF-?-sensitized cells. The decreased anti-tumor effect of sorafenib was rescued by chemical inhibition of ERK and AKT. When TGF-?-sensitized cells were treated with sorafenib plus VPA, the levels of phosphorylated ERK and AKT were considerably suppressed and the numbers of dead cells were increased by 3.7-5.7-fold compared with those exposed to sorafenib alone (P<0.05). Moreover, low dose sorafenib-induced cell migration was effectively suppressed by combination treatment with sorafenib and VPA. Collectively, TGF-?/ERK/AKT signaling might play a critical role in sorafenib resistance in hepatoma cells, and combination treatment with VPA may be effective against this drug resistance. PMID:24817927

  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. Rapid characterization and identification of fatty acids in margarines using horizontal attenuate total reflectance Fourier transform infrared spectroscopy (HATR-FTIR)

    Microsoft Academic Search

    Maylet Hernández-Martínez; Tzayhri Gallardo-Velázquez; Guillermo Osorio-Revilla

    2010-01-01

    Fourier transform infrared spectroscopy (FTIR) with horizontal attenuated total reflectance (HATR) coupled to multivariate\\u000a analysis was used to predict chemical composition, fatty acid profile, nutritional relationships between fatty acids, and\\u000a to identify trans fatty acids (TFA) of margarines. For model building and validation, a set of 42 margarines samples were\\u000a analyzed in terms of fatty acid profile, total fat, moisture,

  9. Restriction of patching of bound concanavalin A after incorporation of arachidonic acid into the plasma membrane of virally transformed fibroblasts

    PubMed Central

    1979-01-01

    Topographical distribution of concanavalin A binding sites (CABS) was studied in two lines of virally transformed fibroblasts as a function of fatty acid composition. Fatty acid composition was manipulated by incubating cells in fatty acid, ATP, CoA, and delipidated fetal calf serum (FCS). VLM cells grown in medium containing 5% FCS have a clustered CABS distribution. Plasma membrane vesicles (PMVs) derived from these cells have an arachidonate content of 1.7%. Elevation of PMV arachidonate to 15.8% results in a marked restriction of CABS patching, while elevation to 6.8% is associated with intermediate restriction of patching. Restriction of patching is associated with increased microviscosity. CABS of Rous sarcoma virus-transformed chicken embryo fibroblasts (RSV-CEF) are also responsive to arachidonate enrichment medium. Whereas untreated cells have a clustered CABS distribution, cells incubated for 24 h in arachidonate enrichment medium have predominantly a dispersed CABS distribution. In both VLM cells and RSV- CEF, ATP, CoA, and delipidated FCS alone have no effect upon CABS mobility. Inhibition of CABS patching is also observed when aspirin is included in the arachidonate enrichment medium but not when the cells are incubated in prostaglandins, thus suggesting that the restriction of CABS mobility is not mediated by prostaglandins. Other fatty acids (palmitate, oleate, nonadecanoate) failed to restrict CABS movement. The inhibition of CABS mobility is independent of cell shape change. PMID:229111

  10. 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

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

    PubMed

    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

  12. Calculations and measurements of the deuterium tunneling frequency in the propiolic acid-formic acid dimer and description of a newly constructed Fourier transform microwave spectrometer

    NASA Astrophysics Data System (ADS)

    Sun, Ming; Wang, Yimin; Carey, Spencer J.; Mitchell, Erik G.; Bowman, Joel; Kukolich, Stephen G.

    2013-08-01

    The concerted proton tunneling frequency for the propiolic acid-formic acid dimer was calculated using a relaxed ab initio double-well potential in the imaginary-frequency mode of the saddle point, and new measurements were made for the deuterated propiolic acid-formic acid (ProOD-FAOD) isotopologue. It is important to have consistent calculated tunneling frequency values between normal and deuterated isotopologues since parameters can be readily adjusted to get good agreement with one isotopologue. High-resolution rotational spectra of deuterated (ProOD-FAOD) dimer were measured using a newly constructed Fourier Transform microwave spectrometer. The new spectrometer has mirror size: 30 cm in diameter with a radius of curvature of 59 cm and is equipped with multiple-FID data collection (5-10 FID's for each gas pulse). For the deuterated (ProOD-FAOD) isotopologue, 45 rotational lines (a type: 34; b type: 11) were measured in the lowest tunneling states range between 6.5 GHz and 15.5 GHz. With the new high-resolution measurements of the tunneling doublets (b-dipole transitions), the double potential well responsible for the deuterium tunneling was depicted much more precisely. The two tunneling states are separated by 3.48 MHz. The rotational constants obtained in this work are quite helpful for further structure analysis as well.

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

    PubMed

    Golebiowski, D; Földes, 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

  14. Fourier transform ion cyclotron resonance mass spectrometry of principal components in oilsands naphthenic acids

    Microsoft Academic Search

    Mark P. Barrow; John V. Headley; Kerry M. Peru; Peter J. Derrick

    2004-01-01

    Naphthenic acids present formidable challenges for the petroleum industry and are a growing concern in the aquatic environment. For example, these acids are responsible for corrosion of refinery equipment, leading to the incurrence of additional costs to the consumer, and are toxic to aquatic wildlife, making disposal and remediation of contaminated waters and sediments a significant problem. The detection and

  15. Telomerase inhibition by peptide nucleic acids reverses `immortality' of transformed human cells

    Microsoft Academic Search

    Masood A Shammas; Carla G Simmons; David R Corey; Robert J Shmookler Reis; RJS Reis

    1999-01-01

    Telomerase activity, the ability to add telomeric repeats to the ends of chromosomes, has been detected in most immortal cell lines including tumor cells, but is low or absent in most diploid, mortal cells such as those of somatic tissues. Peptide nucleic acids (PNAs), analogs of DNA or RNA which bind to complementary nucleic acids with very high affinity, were

  16. 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.

  17. 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.

  18. [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

  19. Structural transformation induced by locked nucleic acid or 2?–O-methyl nucleic acid site-specific modifications on thrombin binding aptamer

    PubMed Central

    2014-01-01

    Background Locked nucleic acid (LNA) and 2'–O-methyl nucleic acid (OMeNA) are two of the most extensively studied nucleotide derivatives in the last decades. However, how they affect DNA quadruplex structures remains largely unknown. To explore their possible biological affinities for quadruplexes, we investigated how LNA- or OMeNA-substitutions affect G-quadruplex structure formation using a thrombin binding aptamer (TBA), the most studied extracorporal G-quadruplex-forming DNA sequence, which is frequently modified to increase its analytical performance. Results The experimental results showed that when two or more nucleotides were substituted with LNA or OMeNA, the anti-parallel TBA structure was transformed into an unstructured random conformation in a 50 mM K+ environment; OMeNA appeared to have greater power to induce this transformation. However, the native TBA was unstructured in a 50 mM Ca2+ environment, whereas four or more LNA- or OMeNA- substitutions could convert this unstructured TBA into a parallel quadruplex structure. PAGE mobility measurements suggested that these TBAs might be a dimeric form. Conclusion LNA or 2'-OMeNA site-specific modifications induced G-quadruplex structural transformation of TBA, which enriched our understanding of the intrinsic G-quadrupex forming property and affinity of LNA and OMeNA modifications. This study demonstrates possible applications in the regulation of gene expression (i.e. manual intervention of gene therapy), genetic analyses, molecular diagnosis and the construction of nano-scale biostructures. PMID:24642032

  20. 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.

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

    PubMed

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

    1992-05-19

    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. PMID:1316157

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

    NASA Astrophysics Data System (ADS)

    Jørgensen, 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.

  3. 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

  4. Monitoring of atmospheric sodium: new method to get the telluric spectrum and influence of the water lines in the performances of LGS

    Microsoft Academic Search

    Sergio Chueca Urzay; Jesus J. Fuensalida

    2000-01-01

    The monitoring of the column density of atmospheric sodium could be crucial for the efficiency of LGS systems. However, its detection is affected by the presence of water lines around the sodium doublet lines; this is really dramatic in the D2 line. We have developed a new method to detect the D2 sodium telluric line, obtaining previously the solar spectrum

  5. 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.

  6. Alkaline phosphatase and an acid arylamidase as marker enzymes for normal and transformed WI-38 cells

    SciTech Connect

    Dolbeare, F.; Vanderlaan, M.; Phares, W.

    1980-01-01

    A survey of eleven enzyme activity levels in normal and SV40 transformed (VA-13) WI-38 cells revealed that the transformed cell enzymes differed by a quantitative and qualitative change of alkaline phosphatase and a quantitative loss of an arylamidase. Alkaline phosphatase activity was found to be elevated in the transformed cells at confluency but not in log phase cultures. While the arylamidase activity from both normal and transformed WI-38 cells had identical pH optima and K/sub m/ values, the activity was approximately 20 times higher in confluent WI-38 cells than in confluent VA-13 cells. Cytochemical staining techniques for both activities are described that permit identification of fluorescent product within the cells, analysis of activity levels, and separation of cells with high and low activities. Mixtures of WI-38 cells and VA-13 cells separated by flow cytometry on the basis of arylamidase activity were subsequently evaluated for alkaline phosphatase isoenzyme and found to have been simultaneously separated into heat labile and heat stable samples.

  7. 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

  8. Concentration dependence of 4-methylbenzophenone choleic acid crystal phosphorescence: Evidence for a percolation driven structural transformation

    NASA Astrophysics Data System (ADS)

    Kook, S.-K.; Kim, D.-Y.; Hanson, D. M.

    1989-12-01

    Steady state phosphorescence spectra at 4.2 K were obtained for different concentrations of 4-methylbenzophenone (MBP) doped into deoxycholic acid (DCA) crystals. The spectra indicate that at concentrations of 14% and below, the sample consists of choleic acid crystals partially filled with MBP and as the concentration increases to 16%, enough guest sites are filled with MBP to cause the local structure to change to that of the stoichiometric crystal. The stoichiometric ratio of DCA to MBP was determined to be 2:1. Spectral shifts characteristic of energy transfer processes are not observed over the concentration range of 4% to 33% MBP.

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

    SciTech Connect

    Zhang, Jingjie [State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Haidian District, Beijing 100191 (China) [State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Haidian District, Beijing 100191 (China); Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 (United States); Ouyang, Weiming; Li, Jingxia; Zhang, Dongyun; Yu, Yonghui; Wang, York [Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 (United States)] [Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 (United States); Li, Xuejun, E-mail: xjli@bjmu.edu.cn [State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Haidian District, Beijing 100191 (China)] [State Key Laboratory of Natural and Biomimetic Drugs, Department of Pharmacology, School of Basic Medical Sciences, Peking University, 38 Xueyuan Rd, Haidian District, Beijing 100191 (China); Huang, Chuanshu, E-mail: chuanshu.huang@nyumc.org [Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 (United States)] [Nelson Institute of Environmental Medicine, New York University School of Medicine, 57 Old Forge Rd, Tuxedo, NY 10987 (United States)

    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.

  10. 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...

  11. 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...

  12. Diffuse Reflectance Fourier Transform Mid-Infrared Spectral Properties of Forages with Varied Fatty Acid Content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ruminant diet can affect the fatty acid (FA) content of meat and dairy products, which indicates that managing forage consumption is important in determining the quality of the animal products. Mid-infrared spectroscopy is sensitive to changes in forage FA and has been used successfully to quantify ...

  13. Diffuse Reflectance Fourier Transform Mid-infrared Spectral Properties of Forages with Varied Fatty Acid Content

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ruminant diet can affect the fatty acid (FA) content of meat and dairy products, which indicates that managing forage consumption is important in determining the quality of the animal products. Mid-infrared spectroscopy is sensitive to changes in forage FA and has been used successfully to quantify ...

  14. An in situ Fourier transform infrared study of formic acid adsorption on a polycrystalline silver catalyst

    Microsoft Academic Search

    G. J. Millar; J. B. Metson; G. A. Bowmaker; R. P. Cooney

    1994-01-01

    Infrared spectra are reported for the adsorption of formic acid on a polycrystalline silver catalyst after various degrees of oxidation. Three distinct chemisorbed species were identified, two of which corresponded to adsorbed formate on Ag(110) and Ag(111) crystal planes and the other to adsorbed formate on a silver site modified by the presence of subsurface oxygen. Moreover, it was discovered

  15. Acute effect of erythromycin on metabolic transformations of volatile fatty acid mixture under anaerobic conditions.

    PubMed

    Cetecioglu, Z; Ince, B; Ince, O; Orhon, D

    2015-04-01

    The study explored the acute inhibitory impact of erythromycin on the methanogenic activity of acclimated biomass fed with a volatile fatty acid mixture and acetate alone. Parallel batch reactors were operated for six days, with increasing erythromycin dosing in the range of 1-1000 mg L(-1). Substrate removal was monitored by means of soluble COD and volatile fatty acid (VFA) measurements together with parallel observations on biogas and methane generation. The inhibitory impact was variable with the initial erythromycin dose: At lower doses, the VFA mixture was completely removed but partially utilized, leading to reduced biogas and methane generation, suggesting the analogy of uncompetitive inhibition. At higher doses, propionate utilization was totally impaired and butyrate removal was reduced, but acetate was still fully removed. Remaining VFAs were partly converted to new VFA compound through isomerization and polymerization reactions. High erythromycin doses induced total inactivation of microbial metabolism with negligible methane generation. PMID:25542637

  16. Lysophosphatidic Acid Interacts with Transforming Growth Factor-? Signaling to Mediate Keratinocyte Growth Arrest and Chemotaxis

    Microsoft Academic Search

    Bettina Sauer; Rüdiger Vogler; Karsten Zimmermann; Makiko Fujii; Mario B. Anzano; Monika Schäfer-Korting; Anita B. Roberts; Burkhard Kleuser

    2004-01-01

    Lysophosphatidic acid (LPA, 1-acyl-glycerol-3-phosphate) plays an important role in diverse biological responses including cell proliferation, differentiation, survival, migration, and tumor cell invasion. The most prominent source of LPA is platelets from which it is released after thrombin activation and is assumed to be an essential function of this lysophospholipid in cutaneous wound closure. Therefore, we examined the role of LPA

  17. Enhancement of Naphthaleneacetic Acid-Induced Rhizogenesis in TL-DNA-Transformed Brassica napus without Significant Modification of Auxin Levels and Auxin Sensitivity

    PubMed Central

    Julliard, Jacques; Sotta, Bruno; Pelletier, Georges; Miginiac, Emile

    1992-01-01

    Determination of the abscisic acid and indoleacetic acid (IAA) contents of floral stem segments of nontransformed and pRi A4 TL-DNA-transformed rape (Brassica napus L. var oleifera, cv Brutor) using a high performance liquid chromatography-enzyme-linked immunosorbent assay procedure and mass spectrometry controls showed that IAA levels were not modified. The regeneration abilities of the in vitro cultured explants were compared on media supplemented with several plant growth regulator combinations. No regeneration occurred on hormone-free media, and shoot production was similar in both genotypes when supplemented with benzyladenine. In the presence of naphthaleneacetic acid (NAA), transformed explants were characterized by faster root regeneration and reduced shoot organogenesis. The optimum for root formation was the same in nontransformed and transformed plants, but the sensitivity threshold was slightly lower in the latter. The NAA inductive period was shorter (14 versus 22 h) with transformed tissue. Root neoformation occurred about 72 h earlier on transformed explants. Our results suggest mainly that there is an acceleration of the auxinic signal transduction and/or that the events preliminary to the formation of roots occur faster in the transformed tissues than in the normal ones. Images Figure 1 PMID:16653117

  18. Structure of pp32, an acidic nuclear protein which inhibits oncogene-induced formation of transformed foci.

    PubMed Central

    Chen, T H; Brody, J R; Romantsev, F E; Yu, J G; Kayler, A E; Voneiff, E; Kuhajda, F P; Pasternack, G R

    1996-01-01

    pp32 is a nuclear protein found highly expressed in normal tissues in those cells capable of self-renewal and in neoplastic cells. We report the cloning of cDNAs encoding human and murine pp32. The clones encode a 28.6-kDa protein; approximately two-thirds of the N-terminal predicts an amphipathic alpha helix containing two possible nuclear localization signals and a potential leucine zipper motif. The C-terminal third is exceptionally acidic, comprised of approximately 70% aspartic and glutamic acid residues; the predicted pI of human pp32 is 3.81. Human and murine pp32 cDNAs are 88% identical; the predicted proteins are 89% identical and 95% similar. Although the structure of pp32 is suggestive of a transcription factor, pp32 did not significantly modulate transcription of a reporter construct when fused to the Gal4 DNA-binding domain. In contrast, in cotransfection experiments, pp32 inhibited the ability of a broad assortment of oncogene pairs to transform rat embryo fibroblasts, including ras + myc, ras + jun, ras + E1a, ras + mutant p53, and E6 + E7. In related experiments, pp32 inhibited the ability of Rat 1a-myc cells to grow in soft agar, whereas it failed to affect ras-induced focus formation in NIH3T3 cells. These results suggest that pp32 may play a key role in self-renewing cell populations where it may act in the nucleus to limit their sensitivity to transformation. Images PMID:8970164

  19. Q-mode curve resolution of UV-vis spectra for structural transformation studies of anthocyanins in acidic solutions.

    PubMed

    Março, Paulo Henrique; Scarminio, Ieda Spacino

    2007-01-30

    Chemometric analysis of ultraviolet-visible (UV-vis) spectra for pH values 1.0, 3.3, 5.3, and 6.9 was used to investigate the kinetics and the structural transformations of anthocyanins in extracts of calyces of hibiscus flowers of the Hibiscus acetosella Welw. ex Finicius for the first time. Six different species were detected: the quinoidal base (A), the flavylium cation (AH+), the pseudobase or carbinol pseudobase (B), cis-chalcone (C(C)), trans-chalcone (C(t)), and ionized cis-chalcone (C(C)-). Four equilibrium constant values were calculated using relative concentrations, hydration, pK(h) = 2.60 +/- 0.01, tautomeric, K(T) = 0.14 +/- 0.01, acid-base, pK(a) = 4.24 +/- 0.04, and ionization of the cis-chalcone, pK(C(C)) = 8.74 +/- 1.5 x 10(-2). The calculated protonation rate of the tautomers is K(H+) = 0.08 +/- 7.6 x 10(-3). These constants are in excellent agreement with those measured previously in salt form. From a kinetic viewpoint, the situation encountered is interesting since the reported investigation is limited to visible light absorption in acid medium. These models have not been reported in the literature. PMID:17386538

  20. Automated acid and base number determination of mineral-based lubricants by fourier transform infrared spectroscopy: commercial laboratory evaluation.

    PubMed

    Winterfield, Craig; van de Voort, F R

    2014-12-01

    The Fluid Life Corporation assessed and implemented Fourier transform infrared spectroscopy (FTIR)-based methods using American Society for Testing and Materials (ASTM)-like stoichiometric reactions for determination of acid and base number for in-service mineral-based oils. The basic protocols, quality control procedures, calibration, validation, and performance of these new quantitative methods are assessed. ASTM correspondence is attained using a mixed-mode calibration, using primary reference standards to anchor the calibration, supplemented by representative sample lubricants analyzed by ASTM procedures. A partial least squares calibration is devised by combining primary acid/base reference standards and representative samples, focusing on the main spectral stoichiometric response with chemometrics assisting in accounting for matrix variability. FTIR(AN/BN) methodology is precise, accurate, and free of most interference that affects ASTM D664 and D4739 results. Extensive side-by-side operational runs produced normally distributed differences with mean differences close to zero and standard deviations of 0.18 and 0.26 mg KOH/g, respectively. Statistically, the FTIR methods are a direct match to the ASTM methods, with superior performance in terms of analytical throughput, preparation time, and solvent use. FTIR(AN/BN) analysis is a viable, significant advance for in-service lubricant analysis, providing an economic means of trending samples instead of tedious and expensive conventional ASTM(AN/BN) procedures. PMID:25271046

  1. The transforming acidic coiled coil (TACC1) protein modulates the transcriptional activity of the nuclear receptors TR and RAR

    PubMed Central

    2010-01-01

    Background The transcriptional activity of Nuclear hormone Receptors (NRs) is regulated by interaction with coactivator or corepressor proteins. Many of these cofactors have been shown to have a misregulated expression or to show a subcellular mislocalization in cancer cell lines or primary tumors. Therefore they can be factors involved in the process of oncogenesis. Results We describe a novel NR coregulator, TACC1, which belongs to the Transforming Acidic Coiled Coil (TACC) family. The interaction of TACC1 with Thyroid Hormone Receptors (TR) and several other NRs has been shown in a yeast two-hybrid screen and confirmed by GST pulldown, colocalization and co-immunoprecipitation experiments. TACC1 interacts preferentially with unliganded NRs. In F9 cells, endogenous TACC1 localized in the chromatin-enriched fraction of the nucleus and interacted with Retinoid Acid Receptors (RAR?) in the nucleus. TACC1 depletion in the cell led to decreased RAR? and TR? ligand-dependent transcriptional activity and to delocalization of TR from the nucleus to the cytoplasm. Conclusions From these experimental studies we propose that TACC1 might be a scaffold protein building up a transcriptional complex around the NRs we studied. This function of TACC1 might account for its involvement in several forms of tumour development. PMID:20078863

  2. An in situ Fourier transform infrared study of formic acid adsorption on a polycrystalline silver catalyst

    SciTech Connect

    Millar, G.J.; Metson, J.B.; Bowmaker, G.A.; Cooney, R.P. (Univ. of Auckland (New Zealand))

    1994-06-01

    Infrared spectra are reported for the adsorption of formic acid on a polycrystalline silver catalyst after various degrees of oxidation. Three distinct chemisorbed species were identified, two of which corresponded to adsorbed formate on Ag(110) and Ag(111) crystal planes and the other to adsorbed formate on a silver site modified by the presence of subsurface oxygen. Moreover, it was discovered that subsurface oxygen species were primarily located in the vicinity of grain boundary defects. Desorption profiles suggested that coadsorbed oxygen moieties could destabilize chemisorbed formate. Because of the invariance in infrared band positions associated with formate species, regardless of whether or not neighbouring atomic oxygen species were present, a kinetic stabilization mechanism is proposed. The pivotal role of subsurface oxygen species (found in the region of grain boundaries) in the mechanism for the selective oxidation of methanol to formaldehyde is discussed. 59 refs., 13 figs.

  3. 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...

  4. Simultaneous production of citric acid and invertase by Yarrowia lipolytica SUC+ transformants.

    PubMed

    Lazar, Zbigniew; Walczak, Ewa; Robak, Ma?gorzata

    2011-07-01

    Simultaneous production of citric acid (CA) and invertase by Yarrowia lipolytica A-101-B56-5 (SUC(+) clone) growing from sucrose, mixture of glucose and fructose, glucose or glycerol was investigated. Among the tested substrates the highest concentration of CA was reached from glycerol (57.15 g/L) with high yield (Y(CA/S)=0.6g/g). When sucrose was used, comparable amount of CA was secreted (45 g/L) with slightly higher yield (Y(CA/S)=0.643 g/g). In all cultures amount of isocitrate (ICA) was below 2% of total citrates. Considering invertase production, the best carbon source appeared to be sucrose (72380 U/L). The highest yield of CA and invertase biosynthesis calculated for 1g of biomass was obtained for cells growing from glycerol (9.9 g/g and 4325 U/g, respectively). Concentrates of extra- and intracellular invertase of the highest activity were obtained from sucrose as substrate (0.5 and 1.8 × 10(6)U/L, respectively). PMID:21549590

  5. Metabolic transformation of DMBA-induced carcinogenesis and inhibitory effect of salvianolic acid b and breviscapine treatment.

    PubMed

    Wei, Jie; Xie, Guoxiang; Ge, Shuyun; Qiu, Yunping; Liu, Wei; Lu, Aiping; Chen, Tianlu; Li, Houkai; Zhou, Zengtong; Jia, Wei

    2012-02-01

    Oral cancer typically develops from hyperplasia through dysplasia to carcinoma with a multistep process of carcinogenesis involving genetic alterations resulting in aberrant cellular appearance, deregulated cell growth, and carcinoma. The metabolic transformation during the process of oral carcinogenesis and its implications for cancer therapy have not been extensively investigated. Here, we report a metabonomic study on a classical model of 7,12-dimethylbenz(a)anthracene (DMBA)-induced oral carcinogenesis in hamsters to delineate characteristic metabolic transformation during the carcinogenesis using gas chromatography time-of-flight mass spectrometry (GC-TOF MS). Salvianolic acid B (Sal-B), isolated from Salvia miltiorrhiza Bge, and Breviscapine, a flavonoid isolated from Herba Erigerontis, were used to treat the hamsters exposed to DMBA to investigate the molecular mechanism of the inhibitory effect of the two agents on oral carcinogenesis. The dynamic changes of serum metabolic profiles indicated that both Sal-B and Breviscapine were able to attenuate DMBA-induced metabolic perturbation, which is consistent with the histopathological findings that Sal-B and Breviscapine significantly decreased the squamous cell carcinoma (SCC) incidence in the two treatment groups. Significant alterations of key metabolic pathways, including elevated glutaminolysis and glycolysis, and decreased cholesterol and myo-inositol metabolism, were observed in the DMBA-induced model group, which were attenuated or normalized by Sal-B or Breviscapine treatment. Elevated inflammation and tumor angiogenesis at gene and metabolite expression levels were also observed in DMBA-induced oral dysplasia and SCC but were attenuated or normalized by Sal-B and Breviscapine along with significantly decreased incidences of SCC formation. PMID:22115128

  6. A new direct Fourier transform infrared analysis of free fatty acids in edible oils using spectral reconstitution.

    PubMed

    Yu, Xiuzhu; van de Voort, F R; Sedman, Jacqueline; Gao, Jin-ming

    2011-07-01

    A new transmission-based Fourier transform infrared (FTIR) spectroscopic method for the direct determination of free fatty acids (FFA) in edible oils has been developed using the developed spectral reconstitution (SR) technique. Conventional neat-oil and SR calibrations were devised by spiking hexanoic acid into FFA-free canola oil and measuring the response to added FFA at 1,712 cm(-1) referenced to a baseline at 1,600 cm(-1)(1,712 cm(-1)/1,600 cm(-1)). To compensate for the known oil dependency of such calibration equations resulting from variation of the triacylglycerol ester (C?O) absorption with differences in oil saponification number (SN), a correction equation was devised by recording the spectra of blends of two FFA-free oils (canola and coconut) differing substantially in SN and correlating the intensity of the ester (C?O) absorption at the FFA measurement location with the intensity of the first overtone of this vibration, measured at 3,471 cm(-1)/3,427 cm(-1). Further examination of the spectra of the oil blends by generalized 2D correlation spectroscopy revealed an additional strong correlation with an absorption in the near-infrared (NIR) combination band region, which led to the development of a second correction equation based on the absorbance at 4,258 cm(-1)/4,235 cm(-1). The NIR-based correction equation yielded superior results and was shown to completely eliminate biases due to variations in oil SN, thereby making a single FFA calibration generally applicable to oils, regardless of SN. FTIR methodology incorporating this correction equation and employing the SR technique has been automated. PMID:21556753

  7. Asiatic acid attenuates cardiac hypertrophy by blocking transforming growth factor-?1-mediated hypertrophic signaling in vitro and in vivo.

    PubMed

    Si, Linjie; Xu, Jing; Yi, Chenlong; Xu, Xiaohan; Wang, Fang; Gu, Weijuan; Zhang, Yuqing; Wang, Xiaowei

    2014-08-01

    Cardiac hypertrophy is a major cause of morbidity and mortality worldwide. Transforming growth factor-?1 (TGF-?1) signaling has been considered as a trigger causally contributing to pathological cardiac hypertrophy. Asiatic acid (AA) is a triterpenoid compound extracted from Centella asiatica and exhibits a variety of pharmacological effects. In this study, we investigated the anti-hypertrophic effects and mechanisms of action of AA in a TGF-?1-stimulated hypertrophic response using cultured neonatal cardiomyocytes in vitro and in a mouse model of cardiac hypertrophy induced by pressure overload in vivo. Treatment with AA markedly attenuated the TGF-?1-induced hypertrophic responses of cardiomyocytes as reflected by reduction in the cardiomyocyte surface area and the inhibition of atrial natriuretic peptide (ANP) mRNA expression. The protective effects of AA on hypertrophic cardiomyocytes were associated with the blocking of p38 and extracellular signal?regulated kinase (ERK)1/2 phosphorylation and the reduction of nuclear factor-?B (NF-?B) binding activity. In vivo experiments indicated that the administration of AA prevented cardiac hypertrophy and dysfunction induced by pressure overload. It was found that AA markedly reduced the excessive production of TGF-?1 in the hypertrophic myocardium, blocked the phosphorylation of p38 and ERK1/2 and inhibited the activation of NF-?B. Our data suggest that AA may be a novel therapeutic agent for cardiac hypertrophy. The inhibition of TGF-?1?mediated hypertrophic signaling may be the mechanism through which AA prevents cardiac hypertrophy. PMID:24827470

  8. The effect of dietary lipid on polyunsaturated fatty acid metabolism in Atlantic salmon (Salmo salar) undergoing parr-smolt transformation.

    PubMed

    Bell, J G; Tocher, D R; Farndale, B M; Cox, D I; McKinney, R W; Sargent, J R

    1997-05-01

    The aim of this study was to measure the changes in lipid metabolism which occur during smoltification and seawater transfer in Atlantic salmon (Salmo salar). Duplicate groups of Atlantic salmon parr were fed diets containing either fish oil (FO) or a blend of linseed and rapeseed oils, vegetable oil (VO), from October (week 0) to seawater transfer in May (week 26). From May to August (weeks 26-43), all fish were fed a fish oil-containing diet. Fatty acyl desaturation and elongation activity were followed in isolated hepatocytes incubated with radioactive 18:3n-3 and 18:2n-6. Metabolism of 18:3n-3 was consistently around 5-fold greater than metabolism of 18:2n-6, and total metabolism of both substrate polyunsaturated fatty acids (PUFA) was increased in fish fed both VO and FO up to seawater transfer after which desaturation activities were reduced. Desaturation activities with both 18:3n-3 and 18:2n-6 were significantly greater in fish fed VO, compared to fish fed FO, at 22 and 26 wk. Arachidonic acid (20:4n-6; AA) in liver polar lipids (PL) of fish fed VO increased consistently from weeks 0-22 but varied after seawater transfer. In fish fed FO, AA in liver PL remained constant up to week 17 before increasing at seawater transfer and leveling off thereafter. Eicosapentaenoic acid (20:5n-3; EPA) in liver PL of fish fed VO decreased significantly from week 0-22 before rising at seawater transfer and increasing rapidly posttransfer. EPA in liver PL of fish fed FO showed a similar trend except EPA was always greater in the freshwater phase compared to fish fed VO. Docosahexaenoic acid (DHA) levels in liver PL of fish fed VO remained constant in the seawater phase before increasing following seawater transfer. In fish fed FO, DHA in liver PL increased from weeks 0-17 reducing and leveling off postseawater transfer. The levels of PGF(2 alpha) and PGF(3 alpha) were measured in isolated gill cells stimulated with calcium ionophore A23187. PGF(2 alpha) production in fish fed VO increased significantly between 0-7 wk before decreasing toward seawater transfer. After transfer, PGF(2 alpha), production increased to a peak at 35 wk. PGF(2 alpha) production in fish fed FO was not significantly altered during the trial period. The changes in PGF(3 alpha) production were broadly similar to those occurring with PGF(2 alpha), but the latter was always in excess of the former (2- to 4-fold). Plasma chloride concentrations in fish subjected to seawater challenge at 20 wk were significantly lower in fish fed VO compared to those fed FO. This study has provided new information on the changes in lipid metabolism which accompany parr-smolt transformation and suggests that diets which have a fatty acid composition more similar to that in aquatic invertebrates may be beneficial in effecting successful seawater adaptation. PMID:9168458

  9. Naphthenic acids as indicators of crude oil biodegradation in soil, based on semi-quantitative electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Hughey, Christine A; Minardi, Carina S; Galasso-Roth, Samantha A; Paspalof, George B; Mapolelo, Mmilili M; Rodgers, Ryan P; Marshall, Alan G; Ruderman, Daniel L

    2008-12-01

    Crude oil contaminated soil cores were collected from a basin that contained oily solids left from three decades of oil production. Hydrocarbon biomarker analyses revealed that the soil extracts were moderately biodegraded compared with the non-degraded source oil. The degree of biodegradation also decreased with core depth (7 cm to 1 m). These data were correlated to compositional changes observed in acidic NSO-compounds that were selectively ionized and mass resolved by negative ion electrospray Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS). Among the NSO-compounds ionized, the increase in naphthenic acid concentration (e.g., acyclic and alicyclic carboxylic acids) best correlated with the increase in biodegradation (e.g., from non-degraded to moderately degraded) as determined by the hydrocarbon biomarker analyses. The most biodegraded surface extracts (7 cm) exhibited an 80% increase in the abundance of acids relative to the source oil. Use of an internal standard allowed the semi-quantitative determination of the total naphthenic acid concentration, which decreased significantly (P < 0.05) with soil depth. Furthermore, the shift to higher double bond equivalents (DBEs), from acyclic to alicyclic acids, indicated that the increase in acids in the soil extracts was predominantly due to biotic processes. This work demonstrates the potential of ESI FT-ICR MS as a semi-quantitative tool to monitor the production of naphthenic acids during crude oil biotransformation in the environment. PMID:19003816

  10. 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.

  11. 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

  12. 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

  13. Fourier Transform Infrared, Solid State Nuclear Magnetic Resonance and X-Ray Diffraction Studies of Natural and Acid Activated Bentonites From Turkey

    Microsoft Academic Search

    Özgür Alver; Burcu Erdo?An Alver

    2012-01-01

    Fourier transform infrared (FT-IR) technique is widely used to distinguish structural properties and to derive information about structural changes following the chemical modification of clays in diffrent conditions. Natural and acid activated bentonites with HCl from Turkey were investigated by FT-IR between the region of 4000-400 cm and the obtained results were supported by Si, Al magic angle spinning nuclear magnetic

  14. Lysosomal acid hydrolases in established lymphoblastoid cell lines, transformed by Epstein-Barr virus, from patients with genetic lysosomal storage diseases

    Microsoft Academic Search

    R. Minami; Y. Watanabe; T. Kudoh; M. Suzuki; K. Oyanagi; T. Orii; T. Nakao

    1978-01-01

    Lysosomal acid hydrolases were determined in established lymphoblastoid cell lines, transformed in vitro by Epstein-Barr virus (EBV) from lymphocyte-rich cell populations isolated from the peripheral blood of patients with genetic lysosomal storage diseases—Hurler syndrome, Scheie syndrome, GM1-gangliosidosis type 1 and type 2, Tay-Sachs disease, and I-cell disease—and from obligate heterozygotes for these diseases.

  15. Effects of methyl jasmonate and salicylic acid on cell growth and cryptotanshinone formation in Ti transformed Salvia miltiorrhiza cell suspension cultures

    Microsoft Academic Search

    Hui Chen; Feng Chen

    1999-01-01

    Exogenous methyl jasmonate (MJ) or salicylic acid (SA) when applied alone failed to induce cryptotanshinone (a phytoalexin) formation in Ti-transformed Salvia miltiorrhiza cell suspension cultures. However, when applied in combination with yeast elicitor, SA at 50–500 µM enhanced the yeast elicitor-induced cryptotanshinone formation while MJ reduced the yeast elicitor-induced cryptotanshinone formation. Ibuprofen at 100 µM did not inhibit the yeast elicitor-induced cryptotanshinone

  16. Lipid characterization of mouse and human fibroblasts and their SV 40-transformed analogues: effects of supplementation with 20alpha hydrocholesterol, linoleic acid, and Sterculia foetida seed oil 

    E-print Network

    Pierce-Ruhland, Richard Arthur

    1981-01-01

    -RUHLAND Submitted to the Graduate Co11ege of Texas ARM University i n parti a1 fuifi 1 lment of the requirement for the deoree of MASTER OF SCIENCE December 198', Major Subject: Biochemistry LIPID CHARACTERIZATION OF MOUSE AND HUMAN FIBROBLASTS AND THEIR SV40... of Department) I December 1981 ABSTRACT Lipid Characterization of Mouse and Human Fibroblasts and Their SV40-Transformed Analogues: Effects of Supplementation with 20m Hydroxycholesterol, Linoleic Acid, and Sterculia foetida Seed Oil. (December 1981...

  17. Transformed and immortalized cellular uptake of oligodeoxynucleoside phosphorothioates, 3?-Alkylamino oligodeoxynucleotides, 2?- o-methyl oligoribonucleotides, oligodeoxynucleoside methylphosphonates, and peptide nucleic acids

    Microsoft Academic Search

    Gary D. Gray; Soumitra Basu; Eric Wickstrom

    1997-01-01

    Direct quantitative comparisons of cellular uptake across a wide variety of analogs and cell types are necessary for the design of oligonucleotide diagnostic and therapeutic applications. This work reports quantitative cellular uptake and nuclear localization of [14C]oligodeoxynucleoside phosphorothioates (PS), 3?-alkylamino Oligodeoxynucleoside phosphodiesters (PO-NH2), 2?-O-methyl oligoribonucleoside phosphodiesters (2OM), peptide nucleic acids (PNA), and oligodeoxynucleoside methylphosphonates (MP) in several transformed or immortalized

  18. Transforming growth factor-alpha and glial fibrillary acidic protein in the hamster circadian system: daily profile and cellular localization.

    PubMed

    Lindley, Jeremy; Deurveilher, Samüel; Rusak, Benjamin; Semba, Kazue

    2008-03-01

    Transforming growth factor-alpha (TGF-alpha) has been identified as a potential output signal of the principal circadian pacemaker housed in the mammalian suprachiasmatic nucleus (SCN). The goal of the present study was to characterize the temporal pattern and cellular localization of TGF-alpha immunoreactivity (IR), and to examine its localization relative to astrocytic and neuronal markers in the hamster circadian system. In contrast to previous reports of circadian rhythms in TGF-alpha mRNA levels in the hamster SCN, we did not detect any statistically significant changes in the levels of TGF-alpha protein IR in the hamster SCN across a 14:10 light-dark cycle using densitometric analyses. TGF-alpha was found to be colocalized with glial fibrillary acidic protein (GFAP), but not with the general neuronal marker NeuN, or calbindin-D28K which is present in a subgroup of SCN neurons. GFAP IR showed a small but significant daily variation in the SCN, with higher levels early in the light phase compared to the middle of the dark phase. The thalamic intergeniculate leaflet (IGL), another component of the circadian regulatory system, did not show any TGF-alpha IR or any detectable daily variation in GFAP IR. These results suggest that daily variations of TGF-alpha mRNA levels in the hamster SCN are not accompanied by corresponding rhythms of TGF-alpha protein levels, and confirm that TGF-alpha is present primarily in astrocytes within the SCN. PMID:18242590

  19. 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

  20. 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, ?-3 and ?-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 ?-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 (?5) fatty acid desaturase gene. A copy of the functional ?5 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

  1. Geophysical images of the Dead Sea Transform in Jordan reveal an impermeable barrier for fluid flow

    Microsoft Academic Search

    O. Ritter; T. Ryberg; U. Weckmann; A. Hoffmann-Rothe; A. Abueladas; Z. Garfunkel

    2003-01-01

    High-resolutionseismictomography and magneto-telluric (MT) soundings of the shallow crust show strong changes in material properties across the Dead Sea Transform Fault (DST) in the Arava valley in Jordan. 2D inversion results of the MT data indicate that the DST is associated with a strong lateral conductivity contrast of a highly conductive layer at a depth of approximately 1.5 km cut-off

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

    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.

  3. 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.

  4. 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

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

    PubMed

    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 ?-linolenic acids, was optimized for a better production. The application of abiotic stress resulted in larger yields of stearidonic and ?-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

  6. 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. (Brigham and Women's Hospital, Boston, MA (USA))

    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.

  7. The Effect of Protic Acid Identity on the Structures of Complexes with Vinyl Chloride: Fourier Transform Microwave Spectroscopy and Molecular Structure of the Vinyl Chloride-Acetylene Complex

    NASA Astrophysics Data System (ADS)

    Leung, Helen O.; Marshall, Mark D.; Feng, Fan

    2013-06-01

    In all previous examples of complexes formed between protic acids and haloethylenes, we have observed similar modes of binding regardless of the specific identity of the acid, HF, HCl, or HCCH. Although details of the structures, such as hydrogen bond length and amount of deviation from linearity, do reflect the strength of the interaction and show clear correlations with the gas-phase acidity, the complexes of a given haloethylene with any of the acids have identical structural motifs. As part of a systematic study of the effects of chlorine substitution on intermolecular interactions of haloethylenes, we have studied the complexes of vinyl chloride with both HF and HCCH. The HF complex, reported last year, has a geometry with HF interacting across the double bond of vinyl chloride and forming a secondary interaction with the hydrogen cis to the chlorine atom. We have obtained the broadband, chirped-pulse and narrow band, Balle-Flygare Fourier transform microwave spectra of the vinyl chloride-HCCH complex. The spectra indicate that HCCH locates at one end of the vinyl chloride with the secondary interaction occurring with the geminal hydrogen atom.

  8. 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.

  9. A rapid method for the quantification of fatty acids in fats and oils with emphasis on trans fatty acids using fourier transform near infrared spectroscopy (FT-NIR)

    Microsoft Academic Search

    Hormoz Azizian; John K. G. Kramer

    2005-01-01

    A rapid method was developed for classifying and quantifying the FA composition of edible oils and fats using Fourier Transform\\u000a near infrared spectroscopy (FT-NIR). The FT-NIR spectra showed unique fingerprints for saturated FA, cis and trans monounsaturated FA, and all n?6 and n?3 PUFA within TAG to permit qualitative and quantitative comparisons of fats and oils.\\u000a The quantitative models were

  10. Effects of land use change on soil gross nitrogen transformation rates in subtropical acid soils of Southwest China.

    PubMed

    Xu, Yongbo; Xu, Zhihong

    2015-07-01

    Land use change affects soil gross nitrogen (N) transformations, but such information is particularly lacking under subtropical conditions. A study was carried out to investigate the potential gross N transformation rates in forest and agricultural (converted from the forest) soils in subtropical China. The simultaneously occurring gross N transformations in soil were quantified by a (15)N tracing study under aerobic conditions. The results showed that change of land use types substantially altered most gross N transformation rates. The gross ammonification and nitrification rates were significantly higher in the agricultural soils than in the forest soils, while the reverse was true for the gross N immobilization rates. The higher total carbon (C) concentrations and C / N ratio in the forest soils relative to the agricultural soils were related to the greater gross N immobilization rates in the forest soils. The lower gross ammonification combined with negligible gross nitrification rates, but much higher gross N immobilization rates in the forest soils than in the agricultural soils suggest that this may be a mechanism to effectively conserve available mineral N in the forest soils through increasing microbial biomass N, the relatively labile organic N. The greater gross nitrification rates and lower gross N immobilization rates in the agricultural soils suggest that conversion of forests to agricultural soils may exert more negative effects on the environment by N loss through NO3 (-) leaching or denitrification (when conditions for denitrification exist). PMID:25772866

  11. Q-mode curve resolution of UV–vis spectra for structural transformation studies of anthocyanins in acidic solutions

    Microsoft Academic Search

    Paulo Henrique Março; Ieda Spacino Scarminio

    2007-01-01

    Chemometric analysis of ultraviolet–visible (UV–vis) spectra for pH values 1.0, 3.3, 5.3, and 6.9 was used to investigate the kinetics and the structural transformations of anthocyanins in extracts of calyces of hibiscus flowers of the Hibiscus acetosella Welw. ex Finicius for the first time. Six different species were detected: the quinoidal base (A), the flavylium cation (AH+), the pseudobase or

  12. 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.

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

    Microsoft Academic Search

    Pedro R. Costa; Rui Rosa; Alexandra Duarte-Silva; Vanda Brotas; Maria Antónia M. Sampayo

    2005-01-01

    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

  14. Influence of gallic acid on the phase transformation in iron oxide layers below organic coatings studied with Moessbauer spectroscopy

    Microsoft Academic Search

    M. Favre; D. Landolt; K. Hoffman; M. Stratmann

    1998-01-01

    The effect of gallic acid on the corrosion reactions underneath paint films on steel during immersion experiments in the presence and absence of oxygen is investigated using Moessbauer spectroscopy. The mass evolution as a function of immersion time is measured for different solid phases such as iron, lepidocrocite, magnetite and ferrous hydroxide. Results show that in the presence of oxygen,

  15. 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 ...

  16. In vivo human skin permeability enhancement by oleic acid: transepidermal water loss and fourier-transform infrared spectroscopy studies

    Microsoft Academic Search

    Hanafi Tanojo; Hans E Junginger; Harry E Boddé

    1997-01-01

    The skin barrier function can be evaluated by measuring the rate of transepidermal water loss (TEWL). This technique can also be used to elucidate the effect of enhancers on the skin barrier. In this in vivo study the effect of oleic acid in propylene glycol (OA\\/PG) has been investigated on 10 human volunteers of both sexes (age: 20–40 years). A

  17. 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; Schröder, 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

  18. Retinoic acid alters hindbrain Hox code and induces transformation of rhombomeres 2\\/3 into a 4\\/5 identity

    Microsoft Academic Search

    Heather Marshall; Stefan Nonchev; Mai Har Sham; Ian Muchamore; Andrew Lumsden; Robb Krumlauf

    1992-01-01

    IT has been suggested that Hox genes play an important part in the patterning of limbs1-3, vertebrae4-6 and craniofacial structures5,7-9 by providing an ordered molecular system of positional values, termed the Hox code10,11. Little is known about the nature of the signals that govern the establishment and regulation of Hox genes, but retinoic acid can affect the expression of these

  19. Biotransformations of racemic 2,3-allenenitriles in biphasic systems: synthesis and transformations of enantioenriched axially chiral 2,3-allenoic acids and their derivatives.

    PubMed

    Ao, Yu-Fei; Wang, De-Xian; Zhao, Liang; Wang, Mei-Xiang

    2014-04-01

    Catalyzed by Rhodococcus erythropolis AJ270 whole cells in an aqueous phosphate buffer-n-hexane biphasic system, racemic axially chiral 2,3-allenenitriles underwent hydrolysis to afford enantioenriched (aR)-2,3-allenamides and (aS)-2,3-allenoic acids with ee's up to >99.5%. Overall biotransformations proceeded through the nitrile hydratase-catalyzed efficient but nonselective hydration of nitriles followed by the amide hydrolysis catalyzed by the substrate-dependent enantioselective amidase. The application of the method has been demonstrated by the transformations of the resulting allene products into highly functionalized heterocyclic compounds with axial chirality of reactants being entirely transferred into or expressed as point chirality of products. PMID:24628470

  20. Transformation of a hydrophilic membrane into semi-super-hydrophobic based on self-assembly of stearic acid monolayer over induced nanostructures on the membrane surface

    NASA Astrophysics Data System (ADS)

    Madaeni, S. S.; Ghaemi, N.

    2007-11-01

    Both the chemical and structural properties of a surface determine the contact angle. For the formation of super-hydrophobic surfaces, modification of surface chemistry must be always combined with surface roughness enhancement. The used methods to make a super-hydrophobic surface are expensive and need very complicated equipments and cannot be scale up easily. In this study a simple and less expensive method was developed to transform a hydrophilic membrane into a semi-super-hydrophobic. In order to modify the membrane surface geometrically, the required needle-like rugosities were created by boiling the membrane in the water. The chemical modification of the roughened surface was created by the chemical adsorption and controlling the reaction time of stearic acid (STA) on the polymer of the membrane surface. Finally, by controlling the surface roughness, the concentration of the STA solution and duration of reaction time, a semi-super-hydrophobic membrane with the contact angle of 120° was prepared.

  1. Metabolic profile of 2-(2-hydroxypropanamido) benzoic acid in rats by ultra high performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Guan, Jiao; Zhang, Qili; Rong, Rong; Han, Fei; Zhu, Heyun; Zhao, Yunli; Song, Aihua; Yu, Zhiguo

    2015-07-01

    An ultra high performance liquid chromatography combined with Fourier transform ion cyclotron resonance mass spectrometry (UHPLC-FT-ICR-MS) method was developed to investigate the in vivo metabolism of 2-(2-hydroxypropanamido) benzoic acid (HPABA), a marine-derived anti-inflammatory drug, for the first time. Plasma, urine, feces and bile samples were collected from male and female rats after a single intragastric administration of HPABA at a dose of 100mg/kg. Besides the parent drug, a total of 13 metabolites (3 phase I and 10 phase II metabolites) were detected and tentatively identified through comparing their mass spectrometry profiles with those of HPABA. Results demonstrated that metabolic pathways of HPABA in rats included decarboxylation, hydroxylation, dehydrogenation, glucuronidation, glycine conjugation and N-acetyl conjugation. In summary, this work provided valuable information regarding the metabolism of HPABA in rats, which would contribute to better understanding of its safety and mechanism of action. PMID:25988429

  2. The evolution of self-assemblies in the mixed system of oleic acid-diethylenetriamine based on the transformation of electrostatic interactions and hydrogen bonds.

    PubMed

    Zhou, Chengcheng; Cheng, Xinhao; Zhao, Oudi; Liu, Shuai; Liu, Chenjiang; Wang, Jide; Huang, Jianbin

    2014-10-28

    With the aid of pH variation, the fine control of the electrostatic interaction and hydrogen bond was realised in the mixed system of oleic acid and diethylenetriamine. Owing to the transformation of the intermolecular interactions, the corresponding building blocks changed from DETA(2+)@2OA(-)via the coexistence of DETA@2OA(-) and DETA(+)@OA(-) to DETA@2OA(-). Therefore, diverse microstructures and phase behaviors in this mixed surfactant system were obtained at the different pH values. It is found that the fine control of the electrostatic interaction and hydrogen bond is efficient for tailoring the self-assembled structures in this cationic-anionic surfactant system, including vesicles, bilayers, networks formed by aggregated vesicles and fibers. PMID:25159624

  3. 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.

  4. A rapid method for the quantification of fatty acids in fats and oils with emphasis on trans fatty acids using Fourier Transform near infrared spectroscopy (FT-NIR).

    PubMed

    Azizian, Hormoz; Kramer, John K G

    2005-08-01

    A rapid method was developed for classifying and quantifying the FA composition of edible oils and fats using Fourier Transform near infrared spectroscopy (FT-NIR). The FT-NIR spectra showed unique fingerprints for saturated FA, cis and trans monounsaturated FA, and all n-6 and n-3 PUFA within TAG to permit qualitative and quantitative comparisons of fats and oils. The quantitative models were based on incorporating accurate GC data of the different fats and oils and FT-NIR spectral information into the calibration model using chemometric analysis. FT-NIR classification models were developed based on chemometric analyses of 55 fats, oils, and fat/oil mixtures that were used in the identification of similar materials. This database was used to prepare three calibration models-one suitable for the analysis of common fats and oils with low levels of trans FA, and the other two for fats and oils with intermediate and high levels of trans FA. The FT-NIR method showed great potential to provide the complete FA composition of unknown fats and oils in minutes. Compared with the official GC method, the FT-NIR method analyzed fats and oils directly in their neat form and required no derivatization of the fats to volatile FAME, followed by time-consuming GC separations and analyses. The FT-NIR method also compared well with the official FTIR method using an attenuated total reflectance (ATR) cell; the latter provided only quantification of specific functional groups, such as the total trans FA content, whereas FT-NIR provided the complete FA profile. The FT-NIR method has the potential to be used for rapid screening and/or monitoring of fat products, trans FA determinations for regulatory labeling purposes, and detection of contaminants. The quantitative FT-NIR results for various edible oils and fats and their mixtures are presented based on the FT-NIR models developed. PMID:16296405

  5. Photo-induced transformations of Hg(II) species in the presence of Nitzschia hantzschiana, ferric ion, and humic acid.

    PubMed

    Deng, Lin; Deng, Nansheng; Mou, Liwei; Zhu, Fangtong

    2010-01-01

    Effects of algae Nitzschia hantzschiana, Fe(III) ions, humic acid, and pH on the photochemical reduction of Hg(II) using the irradiation of metal halide lamps (lambda > or = 365 nm, 250 W) were investigated. The photoreduction rate of Hg(II) was found to increase with increasing concentrations of algae, Fe(III) ions, and humic acid. Alteration of pH value affected the photoreduction of Hg(II) in aqueous solution with or without algae. The photoreduction rate of Hg(II) decreased with increasing initial Hg(II) concentration in aqueous solution in the presence of algae. The photochemical kinetics of initial Hg(II) and algae concentrations on the photoreduction of Hg(II) were studied at pH 7.0. The study on the total Hg mass balance in terms of photochemical process revealed that more than 42% of Hg(II) from the algal suspension was reduced to volatile metallic Hg under the conditions investigated. PMID:20397390

  6. 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

  7. Lipid raft disruption by docosahexaenoic acid induces apoptosis in transformed human mammary luminal epithelial cells harboring HER-2 overexpression.

    PubMed

    Ravacci, Graziela Rosa; Brentani, Maria Mitzi; Tortelli, Tharcisio; Torrinhas, Raquel Suzana M M; Saldanha, Tatiana; Torres, Elizabeth Aparecida F S; Waitzberg, Dan Linetzky

    2013-03-01

    In HER-2-overexpressing breast cells, HER-2 receptors exist on the cell surface as monomers, homodimers and heterodimers. For signal activation and transduction to occur, HER-2 must be localized to lipid rafts. Therefore, we hypothesized that the amount of lipid rafts on the cell membrane would be a factor in HER-2 signaling. To test this, we used HB4a (an untransformed human mammary epithelial cell line) and HB4aC5.2 cells. HB4aC5.2 cells are HB4a derivatives that have been transfected with five copies of pJ5E.c-ErbB-2 and express approximately 900 times more HER-2 than HB4a cells. In these cells, HER-2 overexpression was accompanied by increased lipid rafts in cell membranes, a hyperactivation of downstream Akt and ERK1/2 proteins, and an increased rate of cell growth compared to HB4a. In addition, HER-2 overexpression was associated with an increased activation of FASN, a key enzyme involved in cellular lipogenesis. Its final product, palmitate, is frequently used to synthesize lipid rafts. We further hypothesized that treatment with docosahexaenoic acid (DHA), an omega-3 fatty acid, would disrupt the lipid rafts and lead to a growth arrest. In HB4aC5.2 cells, but not HB4a cells, we found that DHA treatment disrupted lipid raft; inhibited HER-2 signaling by decreasing activation of Akt, ERK1/2 and FASN proteins; and induced apoptosis. Although little is known about lipid rafts, our data support the idea that disturbances in these microdomains induced by DHA may represent a useful tool for controlling the signaling initiated by HER-2 receptors and its therapeutic potential in the treatment of HER-2 positive breast cancer. PMID:22749134

  8. 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...

  9. 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

  10. Studies on the solid acidity of heated and cation-exchanged montmorillonite using n-butylamine titration in non-aqueous system and diffuse reflectance Fourier transform infrared (DRIFT) spectroscopy

    NASA Astrophysics Data System (ADS)

    Liu, Hongmei; Liu, Dong; Yuan, Peng; Tan, Daoyong; Cai, Jingong; He, Hongping; Zhu, Jianxi; Song, Zhiguang

    2013-06-01

    The effects of heating and cation exchange on the solid acidity of montmorillonite were investigated using n-butylamine titration in non-aqueous system and diffuse reflectance Fourier transform infrared spectroscopy. The number of total, Brønsted, and Lewis acid sites showed the same modulation tendency with increasing heating temperature, reaching a maximum at 120 °C and subsequently decreasing until it reaches a minimum at 600 °C. The Lewis acid sites result from unsaturated Al3+ cations, and their number increased with the heating temperature due to the dehydration and dehydroxylation of montmorillonite. The generation and evolution of Brønsted acidity were mainly related to interlayer-polarized water molecules. Water adsorbed on the unsaturated Al3+ ions also acted as a Brønsted acid. The acid strength of the Brønsted acid sites was dependent on the polarization ability of the exchangeable cation, the amount of interlayer water, and the degree of dissociation of the interlayer water coordinated to exchangeable cations. All cation-exchanged montmorillonites exhibited different numbers of acid sites and various distributions of acid strength. Brønsted acidity was predominant in Al3+-exchanged montmorillonite, whereas the Na+- and K+-exchanged montmorillonites showed predominantly Lewis acidity. Moreover, Mg2+- and Li+-exchanged montmorillonites exhibited approximately equal numbers of Brønsted and Lewis acid sites. The Brønsted acidity of cation-exchanged montmorillonite was positively correlated with the charge-to-radius ratios of the cations, whereas the Lewis acidity was highly dependent on the electronegativity of the cations. The acid strengths of Al3+- and Mg2+-exchanged montmorillonites were remarkably higher than those of monovalent cation-exchanged montmorillonites, showing the highest acid strength ( H 0 ? -3.0). Li+- and Na+-exchanged montmorillonites exhibited an acid strength distribution of -3.0 < H 0 ? 4.8, with the acid strength ranging primarily from 1.5 to 3.3 in Li+-exchanged montmorillonite, whereas only weaker-strength acid sites (1.5 < H 0 ? 4.8) were present in K+-exchanged montmorillonite. The results of the catalysis experiments indicated that montmorillonite promoted the thermal decomposition of the model organic. The catalytic activity showed a positive correlation with the solid acidity of montmorillonite and was affected by cation exchange, which occurs naturally in geological processes.

  11. The influence of ethylenediamine tetra acetic acid (EDTA) on the transformation and solubility of metallic palladium and palladium(II) oxide in the environment.

    PubMed

    Zereini, Fathi; Wiseman, Clare L S; Vang, My; Albers, Peter; Schneider, Wolfgang; Schindl, Roland; Leopold, Kerstin

    2015-05-01

    The environmental occurrence of elevated concentrations of platinum (Pt), palladium (Pd) and rhodium (Rh) from automotive catalytic converters has been well-documented. Limited information exists regarding their chemical behavior post-emission, however, especially in the presence of commonly occurring complexing agents. The purpose of this study is to examine the influence of ethylenediamine tetra acetic acid (EDTA) on the possible environmental transformation and solubility of Pd by conducting batch experiments using metallic palladium (Pd black) and palladium(ii) oxide (PdO). Changes in the particle surface chemistry of treated samples were analyzed using X-ray Photoelectron Spectroscopy (XPS) and Transition Electron Microscopy/Energy Dispersive X-ray Spectrometry (TEM/EDX) techniques. Metallic palladium was partially transformed into PdOx (x < 1), while PdO remained largely unaffected. The pH of EDTA solutions was observed to modulate Pd solubility, with Pd black demonstrating a higher solubility compared to PdO. Solubility was also found to increase with a corresponding increase in the strength of EDTA solution concentrations, as well as with the length of extraction time. The overall solubility of Pd remained relatively low for most samples (<1 wt%). A dissolution rate of 2.01 ± 0.17 nmol m(-2) h(-1) was calculated for Pd black in 0.1 M EDTA (pH 7). In contrast to previously held assumptions about the environmental immobility of Pd, small amounts of this element emitted in metallic form are likely to be soluble in the presence of complexing agents such as EDTA. PMID:25816200

  12. Hydrothermal syntheses and structures of the uranyl tellurates AgUO{sub 2}(HTeO{sub 5}) and Pb{sub 2}UO{sub 2}(TeO{sub 6})

    SciTech Connect

    Ling, Jie; Ward, Matthew [Department of Civil Engineering and Geological Science, University of Notre Dame, Notre Dame, IN 46556 (United States); Burns, Peter C., E-mail: pburns@nd.ed [Department of Civil Engineering and Geological Science, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States)

    2011-02-15

    Two uranyl tellurates, AgUO{sub 2}(HTeO{sub 5}) (1) and Pb{sub 2}UO{sub 2}(TeO{sub 6}) (2), were synthesized under hydrothermal conditions and were structurally, chemically, and spectroscopically characterized. 1 crystallizes in space group Pbca, a=7.085(2) A, b=11.986(3) A, c=13.913(4) A, V=1181.5(5) A{sup 3}, Z=8; 2 is in P2(1)/c, a=5.742(1) A, b=7.789(2) A, c=7.928(2) A, V=90.703(2) A{sup 3}, and Z=2. These are the first structures reported for uranyl compounds containing tellurate. The U{sup 6+} cations are present as (UO{sub 2}){sup 2+} uranyl ions that are coordinated by O atoms to give pentagonal and square bipyramids in compounds 1 and 2, respectively. The structural unit in 1 is a sheet consisting of chains of edge-sharing uranyl pentagonal bipyramids that are one bipyramid wide, linked through the dimers of TeO{sub 6} octahedra. In 2, uranyl square bipyramids share each of their equatorial vertices with different TeO{sub 6} octahedra, giving a sheet with the autunite-type topology. Sheets in 1 and 2 are connected through the low-valence cations that are located in the interlayer region. The structures of 1 and 2 are compared to those of uranyl compounds containing octahedrally coordinated cations. -- Graphical abstract: Two hydrothermally synthesized uranyl tellurates, AgUO{sub 2}(HTeO{sub 5}) and Pb{sub 2}UO{sub 2}(TeO{sub 6}), contain sheets built from uranyl pentagonal or square bipyramids, as well as tellurate octahedra. Display Omitted Research highlights: > Compounds AgUO{sub 2}(HTeO{sub 5}) and Pb{sub 2}UO{sub 2}(TeO{sub 6}) are the first uranyl tellurate compounds. > The structure of AgUO{sub 2}(HTeO{sub 5}) consists of sheets of uranyl pentagonal bipyramids and TeO{sub 6} octahedra. > The structure of Pb{sub 2}UO{sub 2}(TeO{sub 6}) contains sheets of TeO{sub 6} octahedra and uranyl square bipyramids.

  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 (?) 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. Collection of VLE data for acid gas - alkanolamine systems using Fourier transform infrared spectroscopy. Final report, September 29, 1990--September 30, 1996

    SciTech Connect

    Bullin, J.A.; Rogers, W.J.

    1996-11-01

    This report describes research from September 29, 1990 through September 30, 1996, involving the development a novel Fourier transform infrared (FTIR) spectroscopic apparatus and method for measuring vapor - liquid equilibrium (VLE) systems of carbon dioxide and hydrogen sulfide with aqueous alkanolamine solutions. The original apparatus was developed and modified as it was used to collect VLE data on acid gas systems. Vapor and liquid calibrations were performed for spectral measurements of hydrogen sulfide and carbon dioxide in the vapor and in solution with aqueous diethanolamine (DEA) and methyldiethanolamine (MDEA). VLE measurements were made of systems of hydrogen sulfide and carbon dioxide in 20 wt % DEA at 50{degrees}C and 40{degrees}C. VLE measurements were made of systems of hydrogen sulfide and carbon dioxide in 50 wt% and 23 wt% MDEA at 40{degrees}C and in 23 wt% MDEA at 50{degrees}C. VLE measurements were made of systems of hydrogen sulfide and carbon dioxide in 35 wt% MDEA + 5 wt% DEA and in 35 wt% MDEA + 10 wt% DEA at 40{degrees}C and 50{degrees}C. Measurements were made of residual amounts of carbon dioxide in each VLE system. The new FTIR spectrometer is now a consistently working and performing apparatus.

  15. Lysophosphatidic acid-induced p21Waf1 expression mediates the cytostatic response of breast and ovarian cancer cells to transforming growth factor beta

    PubMed Central

    Wu, Jinhua; Mukherjee, Abir; Lebman, Deborah A; Fang, Xianjun

    2012-01-01

    Lysophosphatidic acid (LPA) is a multi-functional intercellular phospholipid mediator present in blood and other biological fluids. In cancer cells, LPA stimulates expression or activity of inflammatory cytokines, angiogenic factors, matrix metalloproteinases and other oncogenic proteins. In the present study, we showed that LPA upregulated expression of the cyclin-dependent kinase inhibitor p21Waf1 in transforming growth factor beta (TGF?)-sensitive breast and ovarian cancer cells, but not in TGF?-resistant ones. We examined the possibility that LPA-induced p21 might contribute to the cytostatic response to TGF?. In serum-free conditions, TGF? alone induced p21 expression weakly in TGF?-sensitive cells. Serum or serum-borne LPA cooperated with TGF? to elicit the maximal p21 induction. LPA stimulated p21 via LPA1 and LPA2 receptors and Erk-dependent activation of the CCAAT/enhancer-binding protein beta (C/EBP?) transcription factor independent of p53. Loss or gain of p21 expression led to a shift between TGF? sensitive and resistant phenotypes in breast and ovarian cancer cells, indicating that p21 is a key determinant of the growth inhibitory activity of TGF?. Our results reveal a novel crosstalk between LPA and TGF? that underlies TGF? sensitive and resistant phenotypes of breast and ovarian cancer cells. PMID:21890597

  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. [Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85721 (United States)] [Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85721 (United States); Liu, Ke J. [Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131 (United States)] [Department of Pharmaceutical Sciences, College of Pharmacy, The University of New Mexico, Albuquerque, NM 87131 (United States); Lau, Serrine S. [Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85721 (United States) [Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85721 (United States); Southwest Environmental Health Sciences Center, Department of Pharmacology and Toxicology, The University of Arizona Health Sciences Center, Tucson, AZ 85721 (United States); Gandolfi, A.J., E-mail: wnek@pharmacy.arizona.edu [Department of Pharmacology and Toxicology, College of Pharmacy, The University of Arizona, Tucson, AZ 85721 (United States)

    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. Fluorescence excitation-emission matrix combined with regional integration analysis to characterize the composition and transformation of humic and fulvic acids from landfill at different stabilization stages.

    PubMed

    Xiaoli, Chai; Guixiang, Liu; Xin, Zhao; Yongxia, Hao; Youcai, Zhao

    2012-03-01

    Fluorescence excitation-emission matrix spectroscopy (EEMs) combined with fluorescence regional integration (FRI) analysis was used to investigate the composition and transformation of humic acid (HA) and fulvic acid (FA) from landfill. The EEMs of HAs at different landfill ages were characterized by two typical fluorescence chromophores with Ex/Em pairs at Ex=420-470 nm/Em=490-530 nm and Ex=345-375 nm/Em=450-465 nm. EEMs of FA were featured by other two distinctly different fluorophores with Ex/Em pairs at Ex=315-335 nm/Em=420-440 nm and Ex=255-275 nm/Em=425-455 nm. The results show that HA extracted from the refuse disposed in the year of 1989 was formed by connecting small-condensed aromatic structures with protein-like chains. Compared with HA extracted from the refuse disposed in the year of 1992, HA extracted from the refuse of 1996 had a higher fluorescence intensity and lower r(()(B)(,)(A)()) (the ratio of the fluorescence intensities of peak B and peak A) value. It contained low molar mass components, low aromatic condensation degree, and more easily oxidized substituents. This indicates that the landfill time strongly affects the EEMs characteristics of HA, and that the humification degree of HA increases with the landfill time. A red shift to a longer wavelength region and an increase of fluorescence intensity were observed when the concentration of HA was increased, suggesting that concentration had a great influence on the fluorescence characteristics of HAs. pH (2-12) also had significant effects on the fluorescence intensity, although it exerted no effect on the peak position of fluorescence of HA and FA. The results of FRI show that increasing concentration lead to more interactions among various structure components and that small molecular weight units tend to aggregate or be masked into more complicated and larger structures. The pH influence on the fluorescence intensity of HA seems mainly through molecular configuration, while the fluorescence intensity change with pH may be due to various substituents of FA. PMID:22104617

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

    PubMed Central

    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

    2007-01-01

    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

  19. Cell transformation by viruses

    Microsoft Academic Search

    Joseph L. Melnick; Janet S. Butel; Satvir S. Tevethia; Nilambar Biswal; Matilda Benyesh-Melnick

    1971-01-01

    Summary  This paper describes some current work pertaining to transformation of cells by oncogenic viruses.\\u000a \\u000a Part I includes: (1) the effect of a deoxyribonucleic acid (DNA) tumor virus (SV40) on the antigenic characteristics of transformed\\u000a cells; (2) in vitro and in vivo methods of detecting virus-specific surface antigens; (3) the role that the host cell may\\u000a play in the expression of

  20. 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

  1. Accurate Fourier transform infrared (FT-IR) spectroscopy measurements of nitrogen dioxide (NO2) and nitric acid (HNO3) calibrated with synthetic spectra.

    PubMed

    Flores, Edgar; Viallon, Joële; Moussay, Philippe; Wielgosz, Robert Ian

    2013-10-01

    A novel method for determining the accuracy of laboratory-based measurements of nitrogen dioxide (NO2) and nitric acid (HNO3) mole fractions using Fourier transform infrared (FT-IR) spectroscopy 1 cm(-1) resolution instruments calibrated with synthetic spectra has been developed. The traceability of these measurement results is to the reference line strength data contained within the high-resolution transmission molecular absorption (HITRAN) database. Incorporating a proper estimate of the uncertainty of this data into the measurement results will ensure that the SI traceable values are encompassed within the uncertainty of the measurement results. The major contributors to the uncertainties of the results are, in descending order of importance, the uncertainty in the line strength values (HITRAN 2004), the uncertainty attributed to the generation of reference spectra (including knowledge of the optical path length of the FT-IR gas cell), and temperature measurements of the gas. The stability of the FT-IR instrument itself is only a minor contributor to the overall uncertainty of the measurements. FT-IR measurements of NO2 mole fractions at nominal values of 10 ?mol mol(-1) calibrated with synthetic spectra lead to standard uncertainties of 0.34 ?mol mol(-1) (3.4% relative). In contrast, calibration of the FT-IR instrument with SI traceable gas standards generated by a dynamic weighing system resulted in measurements results with standard uncertainties of 0.04 ?mol mol(-1) (0.4% relative). When comparing the consistency of measurement results based on the synthetic calibration method against those obtained by calibrations with SI traceable gas standards, the existence of a potential bias of ~5% was observed, although this was within the stated uncertainties of the results. The FT-IR measurements of HNO3 mole fractions at nominal values of 200 nmol mol(-1) calibrated with synthetic spectra resulted in values with standard uncertainties of 23 nmol mol(-1) (11% relative) with the dominating uncertainty in this case arising from the stabilization of the mole fraction value within the FT-IR gas cell. PMID:24067574

  2. 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 µmol/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

  3. Biocompatible, pH-sensitive AB(2) Miktoarm Polymer-Based Polymersomes: Preparation, Characterization, and Acidic pH-Activated Nanostructural Transformation.

    PubMed

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

    2012-09-28

    Motivated by the limitations of liposomal drug delivery systems, we designed a novel histidine-based AB(2)-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, mPEG(2kDa)-b-(polyHis(29kDa))(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 µmol/mg polymer, mPEG(2kDa)-b-(polyHis(29kDa))(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 mPEG(2kDa)-b-(polyHis(29kDa))(2) nanostructures may be caused by the increasing hydrophilic weight fraction of mPEG(2kDa)-b-(polyHis(29kDa))(2) and can help to disrupt the endosomal membrane through proton buffering and membrane fusion of mPEG(2kDa)-b-(polyHis(29kDa))(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

  4. Biosynthesis of phenylalanine, tyrosine, 3-(3-carbocyphenyl) alanine and 3-(3-carbocy-4-hydroxyphenyl) alanine in higher plants. Examples of the transformation possibilities for chorismic acid.

    PubMed

    Larsen, P O; Onderka, D K; Floss, H G

    1975-02-13

    14C-labelled shikimic acid and double labelled shikimic acid tritiated stereospicifically at C-6 are incorporated into 3-(3-carboxyphenyl) alanine, 3-(3-carboxy-4-hydroxyphenyl) alanine, phenylalanine, and tyrosine in Reseda lutea L., Reseda odorata L., Iris x Hollandica cv. Prof. Blauw, and Iris x hollandica cv. Wedgwood. The experiments with 14C-labelled shikimic acid confirm that the aromatic carboxyl groups and rings in 3-(3-carboxyphenyl) alanine and 3-(3-carbocy-4-hydroxyphenyl) alanine derive from the carbocyl group and ring in shikimic acid whereas the experiments with double labelled shikimic acid demonstrate that the pro-6S-hydrogen atom is retained and the pro-6R-hydrogen atom lost in the biosynthesis of 3-(3-carboxyphenyl) alanine, phenylalanine, and tyrosine in the plants used. 3H was located in the ortho-position in the aromatic rings of phenylalanine and tyrosine but in a position para to the alanine side chain of 3- (3-carboxyphenly) alanine. No 3H was found in 3- (3-carboxy-4-hydroxyphenyl) alanine. This supports a derivation of the last two compounds from chorismic acid via isochorismic acid, isoprephenic acid, and 3'-carboxyphenylpyruvic acid and 3'-carbocy-4'-hydroxyphenylphruvic acid. The 3H/14C ratio in 3-(3-carboxyphenyl) alanine was found higher than in the precursor used. This isotope effect must operate by competition between the pathways from isoprephenic acid to 3'-carbocyphenylpyruvic acid and to 3'-carbocy-4'- hydroxyphenylpyruvic acic. The proposed biosynthetic pathways for the two carboxy-substituted amino acids are in agreement with their distribution patterns in the plant kingdom and suggest that they may derive from minor changes of enzymes involved in the general pathways of aromatic biosynthesis. PMID:1120151

  5. Effect of salicylic acid, methyl jasmonate, ethephon and cantharidin on anthraquinone production by Rubia cordifolia callus cultures transformed with the rolB and rolC genes

    Microsoft Academic Search

    V. P. Bulgakov; G. K. Tchernoded; N. P. Mischenko; M. V. Khodakovskaya; V. P. Glazunov; S. V. Radchenko; E. V. Zvereva; S. A. Fedoreyev; Yu. N Zhuravlev

    2002-01-01

    It has been suggested that the rol genes of Agrobacterium rhizogenes could play an essential role in the activation of secondary metabolite production in plant transformed cultures. This study investigated whether the content of anthraquinone phytoalexins was changed in callus cultures of Rubia cordifolia transgenic for the 35S-rolB and 35S-rolC genes in comparison with a non-transformed callus culture. The anthraquinone

  6. The effect of pH on the transformation of syringic and vanillic acids by the laccases of Rhizoctonia praticola and Trametes versicolor

    Microsoft Academic Search

    A. Leonowicz; R. U. Edgehill; J.-M. Bollag

    1984-01-01

    Laccases (benzenediol: oxygen oxidoreductases, EC 1.10.3.2) from Rhizoctonia praticola and Trametes versicolor formed different products from syringic and vanillic acids at different pH values, but both enzymes generated the same chemicals at a particular pH. The products were separated by thin-layer and high-performance liquid chromatography. Four compounds were determined from syringic acid (m\\/z 168, 334, 350 and 486) at pH

  7. transformations: representations

    E-print Network

    Nguyen, Dat H.

    Overview 1. Number transformations: from one base to another 2. Integer representations 3. Real rate, caches... #12; ECS 50, Discussion on 4/25 2 Integer Transformation: From Decimal to Binary Let, Discussion on 4/25 3 Integer Transformation: From Binary to Decimal Compute the weight of each digit position

  8. Transformation Composition

    E-print Network

    Drewes, Frank

    Proc. AGTIVE'99, to appear in LNCS Graph Transformation Modules and their Composition ? Frank,knirsch,kreo,kuskeg@informatik.uni-bremen.de Abstract. In this paper, we investigate the notion of transformation modules as a structuring principle. Based on the notion of transformation units, a concept that allows to specify binary relations on graphs

  9. 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

  10. 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...

  11. Animating Transformations

    NSDL National Science Digital Library

    Roberts, Lila F.

    2003-01-24

    In most introductory linear algebra courses, prominent applications of transformations or mappings are moving (rotating, reflecting, translating), resizing (contracting, expanding), changing the shape (shearing, projecting) objects in the plane. A typical problem in such courses is to write the matrix of a transformation that changes points in such prescribed ways. The goal of this demo is to help students more easily visualize such transformations on a wide class of plane objects.

  12. Prediction of protein structural classes by Chou’s pseudo amino acid composition: approached using continuous wavelet transform and principal component analysis

    Microsoft Academic Search

    Zhan-Chao Li; Xi-Bin Zhou; Zong Dai; Xiao-Yong Zou

    2009-01-01

    A prior knowledge of protein structural classes can provide useful information about its overall structure, so it is very\\u000a important for quick and accurate determination of protein structural class with computation method in protein science. One\\u000a of the key for computation method is accurate protein sample representation. Here, based on the concept of Chou’s pseudo-amino\\u000a acid composition (AAC, Chou, Proteins:

  13. Development of a multichannel Fourier-transform spectrometer to measure weak chemiluminescence: Application to the emission of singlet-oxygen dimol in the decomposition of hydrogen peroxide with gallic acid and K 3[Fe(CN) 6

    NASA Astrophysics Data System (ADS)

    Tsukino, Kazuo; Satoh, Toshihiro; Ishii, Hiroshi; Nakata, Munetaka

    2008-05-01

    A Fourier-transform spectrometer equipped with a Savart-plate polarization interferometer was developed for observation of weak chemiluminescence and applied to a measurement of emission spectra in the decomposition of hydrogen peroxide with gallic acid and K 3[Fe(CN) 6]. The band appearing at ˜580 nm in the chemiluminescence spectrum was assigned to the emission of singlet-oxygen dimol, the peak wavelength being shifted from that observed in the reaction of hydrogen peroxide with sodium hypochlorite, ˜633 nm. The band intensity was increased with the increasing concentration of K 3[Fe(CN) 6] up to ˜100 mM, and thereafter the peak wavelength was shifted from 580 to 700 nm with a decrease in the intensity.

  14. The application of the yeast N-acetyltransferase MPR1 gene and the proline analogue L-azetidine-2-carboxylic acid as a selectable marker system for plant transformation

    PubMed Central

    Tsai, Fei-Yi; Ulanov, Alexander; Widholm, Jack M.

    2010-01-01

    The yeast N-acetyltransferase MPR1 gene has previously been shown to confer resistance to the toxic proline analogue azetidine-2-carboxylic acid (A2C) in yeast and transgenic tobacco. Here experiments were carried out to determine if MPR1 and A2C can work as a selectable marker system for plant transformation. The MPR1 gene was inserted into a binary vector under the control of the cauliflower mosaic virus 35S promoter and nopaline synthase terminator, and transformed into tobacco via the Agrobacterium tumefaciens-mediated leaf disc method. A2C was applied in the selection medium to select for putative transformants. PCR analysis showed that 28.4% and 66.7% of the plantlets selected by 250??M and 300??M A2C were positive for the MPR1 gene, respectively. Southern and northern blot analysis and enzyme activity assay confirmed the stable gene incorporation, transcription, and translation of the MPR1 transgene in the transgenic plants. The transgene-carrying T1 progeny could be distinguished from the recessive progeny when grown on 400, 450, or 500??M A2C. Examination of the metabolism of 22 transgenic plants by gas chromatography–mass spectrometry profiling did not reveal any significant changes. In conclusion, the results demonstrate that MPR1/A2C is a safe and efficient selection system that does not involve microbial antibiotic or herbicide resistance genes. Recent studies showed that MPR1 can protect yeast against oxidative stresses by decreasing the accumulation of the proline catabolite ?1-pyrroline-5-carboxylate (P5C). However, H2O2 treatment resulted in contradictory responses among the five transgenic lines tested. Further experiments are required to assess the response of MPR1 transgenic plants under oxidative stress. PMID:20430752

  15. [Transformation toughening

    SciTech Connect

    Rafa, M.J.

    1993-04-19

    In NiAl, we have succeeded in determining the complete Ginzburg-Landau strain free energy function necessary to model the cubic to tetragonal martensite transformation in a sample of any size. We believe that this is the first time that the parameters of a Ginzburg-Landau functional and the complete strain spinodal for any three-dimensional displacive transformation were used in simulating the transformation near a crack tip under Mode I loading; the transformation pattern and toughening are different from standard transformation toughening theories. Furthermore, the strain spinodal has an approximately conical shape which can be specified by two material dependent experimentally accessible parameters, rather than the ellipsoidal shape in standard theories. Stress induced martensitic transformation in a polycrystalline sample of NiAl was simulated. In the ZrO[sub 2] system, first principles calculations to determine the semi-empirical potentials for simulating the cubic-tetragonal and tetragonal-monoclinic transformations have been started by doing a more elaborate total energy calculation.In the Al[sub 2]0[sub 3] system, we have discovered that the first principles calculations and semi-empirical potentials have just been completed byanother group in England which we will use instead to base our molecular dynamics simulations on.

  16. 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.

  17. 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.

  18. Transforming California

    NSDL National Science Digital Library

    Thomas McGuire

    2001-01-01

    Transforming California is a PowerPoint presentation of digital images (60.7 Mb) exploring the landforms found along the San Andreas Fault. Designed for classroom use, this slideshow provides a complementing narrative for each slide.

  19. Transformative copy

    E-print Network

    Offenhuber, Dietmar

    2008-01-01

    The ability to create an unlimited number of identical copies is a privilege of digital documents. What if that would not be the case, if each copy of a digital file would go along with some sort of transformation? This ...

  20. Transforming America's Energy Economy Transforming America's

    E-print Network

    #12;Transforming America's Energy Economy Transforming America's Energy Economy This document #12;Transforming America's Energy Economy A. Introduction: A Call for Action B. Envisioning the Future.5 Energy Efficiency C. Charting the Path Forward 1 #12;Transforming America's Energy Economy

  1. SPATIAL TRANSFORMATIONS 1 Running head: Spatial transformations

    E-print Network

    Zacks, Jeffrey M.

    SPATIAL TRANSFORMATIONS 1 Running head: Spatial transformations Multiple Systems for Spatial Imagery: Transformations of Objects and Bodies Jeffrey M. Zacks* and Barbara Tversky * Washington COGNITION & COMPUTATION #12;SPATIAL TRANSFORMATIONS 2 Abstract Problem-solving often requires imagining

  2. Organic additive, 5-methylsalicylic acid induces spontaneous structural transformation of aqueous pluronic triblock copolymer solution: a spectroscopic investigation of interaction of curcumin with pluronic micellar and vesicular aggregates.

    PubMed

    Ghosh, Surajit; Kuchlyan, Jagannath; Banik, Debasis; Kundu, Niloy; Roy, Arpita; Banerjee, Chiranjib; Sarkar, Nilmoni

    2014-10-01

    This article presents the interaction of curcumin in the microenvironments provided by aggregation of pluronic triblock copolymer P123 into micellar and vesicular assemblies. The formation of vesicles using triblock copolymer P123 and 5-methylsalicylic acid (5 mS) has been successfully characterized by optical spectroscopy, light scattering measurement, and eventually microscopic techniques. Besides, to make a comparative study between the polymeric micelles, we have also investigated the photophysical changes of curcumin in F127 triblock copolymer micelles having variation in poly(ethylene oxide) (PPO) and poly(propylene oxide) (PEO) unit of polymer chain to that of P123. Time-dependent UV-vis measurement suggests that these polymer micelles are able to stabilize poorly water-soluble curcumin by suppressing the degradation rate in micellar nanocavity. However, experimental observations suggest that P123 micelles are more efficient than F127 to perturb excited state intramolecular proton transfer (ESIPT)-related nonradiative decay of curcumin. We also observed that rigid and confined microenvironment of P123/5 mS vesicles enhances emission intensity and lifetime of curcumin more compared to P123 micelles. All the observations suggest that modulation of photophysics of curcumin is responsible due to its interaction with poly(ethylene oxide) or poly(propylene oxide) unit of triblock copolymer. PMID:25192258

  3. Unraveling the Difference between Invertases and Fructan Exohydrolases: A Single Amino Acid (Asp-239) Substitution Transforms Arabidopsis Cell Wall Invertase1 into a Fructan 1-Exohydrolase1[C

    PubMed Central

    Le Roy, Katrien; Lammens, Willem; Verhaest, Maureen; De Coninck, Barbara; Rabijns, Anja; Van Laere, André; Van den Ende, Wim

    2007-01-01

    Plant cell wall invertases and fructan exohydrolases (FEHs) are very closely related enzymes at the molecular and structural level (family 32 of glycoside hydrolases), but they are functionally different and are believed to fulfill distinct roles in plants. Invertases preferentially hydrolyze the glucose (Glc)-fructose (Fru) linkage in sucrose (Suc), whereas plant FEHs have no invertase activity and only split terminal Fru-Fru linkages in fructans. Recently, the three-dimensional structures of Arabidopsis (Arabidopsis thaliana) cell wall Invertase1 (AtcwINV1) and chicory (Cichorium intybus) 1-FEH IIa were resolved. Until now, it remained unknown which amino acid residues determine whether Suc or fructan is used as a donor substrate in the hydrolysis reaction of the glycosidic bond. In this article, we present site-directed mutagenesis-based data on AtcwINV1 showing that the aspartate (Asp)-239 residue fulfills an important role in both binding and hydrolysis of Suc. Moreover, it was found that the presence of a hydrophobic zone at the rim of the active site is important for optimal and stable binding of Suc. Surprisingly, a D239A mutant acted as a 1-FEH, preferentially degrading 1-kestose, indicating that plant FEHs lacking invertase activity could have evolved from a cell wall invertase-type ancestor by a few mutational changes. In general, family 32 and 68 enzymes containing an Asp-239 functional homolog have Suc as a preferential substrate, whereas enzymes lacking this homolog use fructans as a donor substrate. The presence or absence of such an Asp-239 homolog is proposed as a reliable determinant to discriminate between real invertases and defective invertases/FEHs. PMID:17873089

  4. Microbial Transformation of Quercetin by Bacillus cereus

    PubMed Central

    Rao, Koppaka V.; Weisner, Nghe T.

    1981-01-01

    Biotransformation of quercetin was examined with a number of bacterial cultures. In the presence of a bacterial culture (Bacillus cereus), quercetin was transformed into two crystalline products, identified as protocatechuic acid and quercetin-3-glucoside (isoquercitrin). PMID:16345844

  5. Ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride as a novel matrix for rapid quantitative and qualitative determination of serum free fatty acids by matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry.

    PubMed

    Zhang, Yaping; Wang, Yanmin; Guo, Shuai; Guo, Yumei; Liu, Hui; Li, Zhili

    2013-09-10

    The blood free fatty acids (FFAs), which provide energy to the cell and act as substrates in the synthesis of fats, lipoproteins, liposaccharides, and eicosanoids, involve in a number of important physiological processes. In the present study, matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR MS) with ammonia-treated N-(1-naphthyl) ethylenediamine dihydrochloride (ATNEDC) as a novel MALDI matrix in a negative ion mode was employed to directly quantify serum FFAs. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to internal standard (IS, C17:0) versus their corresponding intensity ratios were constructed for C14:0, C16:1, C16:0, C18:0, C18:1, C18:2, C18:3, C20:4, and C22:6, respectively, in their mixture, with correlation coefficients between 0.991 and 0.999 and limits of detection (LODs) between 0.2 and 5.4?M, along with the linear dynamic range of more than two orders of magnitude. The results indicate that the multiple point internal standard calibration could reduce the impact of ion suppression and improve quantification accuracy in the MALDI mode. The quantitative results of nine FFAs from 339 serum samples, including 161 healthy controls, 118 patients with hyperglycemia and 60 patients without hyperglycemia show that FFAs levels in hyperglycemic patient sera are significantly higher than those in healthy controls and patients without hyperglycemia, and elevated FFA levels are also associated with increased levels of fasting blood glucose (FBG) in hyperglycemic patient sera. Serum FFAs were identified on the basis of the observed accurate molecular masses and reliable isotope distributions obtained by MALDI-FTICR MS. PMID:23972979

  6. The Laplace Transform 1 Laplace transform and inverse transform

    E-print Network

    Yengulalp, Lynne

    The Laplace Transform Name: 1 Laplace transform and inverse transform Definition. Let f(t) be a function defined for t 0. Then the integral L {f(t)} = 0 e-st f(t)dt is said to be the Laplace transform of f provided the integral converges. Fill in the following Laplace transforms. L {tn } = L {eat } = L

  7. 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.

  8. 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…

  9. 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

  10. 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…

  11. Key roles for GRB2-associated-binding protein 1, phosphatidylinositol-3-kinase, cyclooxygenase 2, prostaglandin E2 and transforming growth factor alpha in linoleic acid-induced upregulation of lung and breast cancer cell growth.

    PubMed

    Mouradian, M; Kikawa, K D; Johnson, E D; Beck, K L; Pardini, R S

    2014-04-01

    The distribution of omega-6 and omega-3 polyunsaturated fatty acid (PUFA) intake in Western diets is disproportionate, containing an overabundance of the omega-6 PUFA, linoleic acid (LA; C18:2). Increased enrichment with LA has been shown to contribute to the enhancement of tumorigenesis in several cancer models. Previous work has indicated that phosphatidylinositol 3-kinase (PI3K) may play a key role in LA-induced tumorigenesis. However, the modes by which LA affects carcinogenesis have not been fully elucidated. In this study, a mechanism for LA-induced upregulation of cancer cell growth is defined. LA treatment enhanced cellular proliferation in BT-474 human breast ductal carcinoma and A549 human lung adenocarcinoma cell lines. Enrichment of LA increased cyclooxygenase (COX) activity and led to increases in prostaglandin E2 (PGE2), followed by increases in matrix metalloproteinase (MMP) and transforming growth factor alpha (TGF-?) levels, which are all key elements involved in the enhancement of cancer cell growth. Further investigation revealed that LA supplementation in both BT-474 breast and A549 lung cancer cell lines greatly increased the association between the scaffolding protein GRB2-associated-binding protein 1 (Gab1) and epidermal growth factor receptor (EGFR), although Gab1 protein levels were significantly decreased. These LA-induced changes were associated with increases in activated Akt (pAkt), a downstream signaling component in the PI3K pathway. Treatment with inhibitors of EGFR, PI3K and Gab1-specific siRNAs reversed the upregulation of pAkt, as well as the observed increases in cell proliferation by LA in both cell lines. A549 xenograft assessment in athymic nude mice fed high levels of LA exhibited similar increases in EGFR-Gab1 association and increased levels of pAkt, while mice fed with high levels of the omega-3 PUFA, docosahexaenoic acid (DHA; C22:6), demonstrated an opposite response. The involvement of Gab1 in LA-induced tumorigenesis was further defined utilizing murine cell lines that express high levels of Gab1. Significant increases in cell proliferation were observed with the addition of increasing concentrations of LA. However, no changes in cell proliferation were detected in the murine paired cell lines expressing little or no Gab1 protein, establishing Gab1 as major target in LA-induced enhancement of tumorigenesis. PMID:24374147

  12. 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

  13. Ursodeoxycholic acid, 7-ketolithocholic acid, and chenodeoxycholic acid are primary bile acids of the nutria (Myocastor coypus).

    PubMed

    Tint, G S; Bullock, J; Batta, A K; Shefer, S; Salen, G

    1986-03-01

    Because ursodeoxycholic and chenodeoxycholic acids are interconverted in humans via 7-ketolithocholic acid, bile acid metabolism was studied in the nutria (Myocastor coypus), the bile of which is known to contain these three bile acids. Relative concentrations of ursodeoxycholic (37% +/- 20%), 7-ketolithocholic (33% +/- 17%), and chenodeoxycholic (17% +/- 9%) acids in gallbladder bile were unchanged by 5-20 h of complete biliary diversion (n = 7). Injection of either [14C]cholesterol, [14C]ursodeoxycholic, [14C]7-ketolithocholic acid, or a mixture of [7 beta-3H]chenodeoxycholic acid and [14C]chenodeoxycholic acid into bile fistula nutria demonstrated that all three bile acids can be synthesized hepatically from cholesterol, that they are interconverted sparingly (2%-5%) by the liver, but that 7-ketolithocholic acid is an intermediate in the hepatic transformation of chenodeoxycholic acid to ursodeoxycholic acid. An animal that had been fed antibiotics showed an unusually elevated concentration of ursodeoxycholic acid in gallbladder and hepatic bile, suggesting that bacterial transformation of ursodeoxycholic acid in the intestine may be a source of some biliary chenodeoxycholic acid and 7-ketolithocholic acid. PMID:3943698

  14. Transformations Journal

    NSDL National Science Digital Library

    Different forms of communication have always had a tendency to transform interactions and everyday life in ways that have surprised people from many different backgrounds. Academics have long been interested in such dynamic transformations, and this electronic journal represents one of the responses to such processes. As their site notes, this journal is "dedicated to the exploration of ideas, issues and debates emerging out of contemporary global culture." Visitors to the site can read the complete version of every issue on the site, and they will be pleased to find such intriguing titles as "Rethinking Regionality", "Accidental Environments", and "Fleeing the City". Interested parties can also consult the site to learn about the journal's editorial board, their calls for papers, submission guidelines, and related links.

  15. Transformers Transformer device used to raise (for

    E-print Network

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    Transformers Transformer ­ device used to raise (for transmission) and lower (for use) the ac with different #s of turns #12;Transformers Alternating primary current induces alternating magnetic flux in iron dt d NV B PP -= dt d NV B SS -= S S P P N V N V = #12;Transformers Transformation of voltage

  16. Pulse transformers

    Microsoft Academic Search

    H. Lord

    1971-01-01

    Pulse transformers capable of transmitting substantially rectangular voltage pulses, with durations of less than one microsecond, were developed for radar applications during World War II. Their primary functions were to match the impedances of high-power microwave radio-frequency electron-tube generators to electronic pulse generators and coaxial transmission cables, and to provide polarity reversal and impedance matching functions within pulse generator circuitry.

  17. 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

  18. Transformations - Dilation

    NSDL National Science Digital Library

    2003-01-01

    In this interactive simulation, students are able to visualize and manipulate objects to understand dilation transformations. Students are able to adjust the center of dilation, rotate and move figures, change the scale factor to see what effect it has on the figures, add their own figures, and more. Across the top of the page, visitors will find links to activities to guide students as they explore the site, and more advanced activities involving computation are available in the Parent/Teacher section. The Instructions sections has detailed information for students and teachers alike on how to use the manipulative.

  19. PHASE TRANSFORMATIONS IN ALUMINA. Technical Report, May to December 1961

    Microsoft Academic Search

    H. J. Eding; M. L. Huggins; A. G. Brown

    1961-01-01

    e transformation studies showed that synthetic aluminas produced in ; the laboratory were not transformed to alpha alumina at 400 to 700' deg n the ; presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot ; plant was transformed to alpha alumina. This indicated that the amorphous ; alumina produced in the pilot plant is structurally

  20. High-throughput and high-sensitivity quantitative analysis of serum unsaturated fatty acids by chip-based nanoelectrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry: early stage diagnostic biomarkers of pancreatic cancer.

    PubMed

    Zhang, Yaping; Qiu, Ling; Wang, Yanmin; Qin, Xuzhen; Li, Zhili

    2014-04-01

    In this study, Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) coupled with chip-based direct-infusion nanoelectrospray ionization source (CBDInanoESI) in a negative ion mode is first employed to evaluate the effect of serum and its corresponding supernatant matrixes on the recoveries of serum free fatty acids (FFAs) based on spike-and-recovery experimental strategy by adding analytes along with analog internal standard (IS). The recoveries between serum (69.8-115.6%) and the supernatant (73.6-99.0%) matrixes are almost identical. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to ISs, (C(17:1) as IS of C(16:1), C(18:3), C(18:2), or C(18:1) or C(21:0) as IS of C(20:4) or C(22:6)) versus their corresponding intensity ratios were constructed for C(16:1), C(18:3), C(18:2), C(18:1), C(20:4) and C(22:6), respectively, with correlation coefficients of greater than 0.99, lower limits of detection between 0.3 and 1.8 nM, and intra- and inter-day precision (relative standard deviations <18%), along with the linear dynamic range of three orders of magnitude. Sequentially, this advanced analytical platform was applied to perform simultaneous quantitative and qualitative analysis of multiple targets, e.g., serum supernatant unsaturated FFAs from 361 participants including 95 patients with pancreatic cancer (PC), 61 patients with pancreatitis and 205 healthy controls. Experimental results indicate that the levels of C(18:1), C(18:2), C(18:3), C(20:4) and C(22:6), as well as the level ratios of C(18:2)/C(18:1) and C(18:3)/C(18:1) of the PC patients were significantly decreased compared with those of healthy controls and the patients with pancreatitis (p < 0.01). It is worth noting that the ratio of C(18:2)/C(18:1), polyunsaturated fatty acids (PUFAs) (C(18:2), C(18:3), C(20:4), and C(22:6)), panel a (C(16:1), C(18:3), C(18:2), C(20:4) and C(22:6)) and panel b (C(18:2)/C(18:1) and C(18:3)/C(18:1)) performed excellent diagnostic ability, with an area under the receiver operating characteristic curve of ?0.869, sensitivity of ?85.7%, and specificity of ?86.7% for differentiating the early stage PC from non-cancer subjects, which are greatly higher than those of clinically used serum biomarker CA 19-9. More importantly, this platform can also provide a fast and easy way to quantify the levels of FFAs in less than 30 s per sample. PMID:24551873

  1. Hough Transform from the Radon Transform

    Microsoft Academic Search

    Stanley R. Deans

    1981-01-01

    An appropriate special case of a transform developed by J. Radon in 1917 is shown to have the major properties of the Hough transform which is useful for finding line segments in digital pictures. Such an observation may be useful in further efforts to generalize the Hough transform. Techniques for applying the Radon transform to lines and pixels are developed

  2. Testability Transformation: Program Transformation to Improve Testability

    E-print Network

    Singer, Jeremy

    Testability Transformation: Program Transformation to Improve Testability An Overview of Recent Author. Abstract. Testability transformation is a new form of program transfor- mation in which the goal to some chosen test adequacy criterion. The goal is to improve the testing process by transforming

  3. Testability Transformation --Program Transformation to Improve Testability

    E-print Network

    Binkley, David W.

    Testability Transformation -- Program Transformation to Improve Testability Mark Harman1 , Andr, 26 Richmond Street, Glasgow G1 1XH, UK. Corresponding Author. Abstract. Testability transformation. The goal is to improve the testing process by transforming a program to one that is more amenable

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

    PubMed

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

    2010-06-01

    Nanotube titanic acid (NTA) has distinct optical and electrical character, and has photocatalysis character. In accordance with these qualities, NTA was treated with acid so as to enhance its surface activity. Surface structures and surface groups of acid-treated NTA were characterized and analyzed by Transmission Electron Microscope (TEM) and Fourier Transform Infrared Spectrometry (FT-IR). The interaction between acid-treated NTA and amino acids was investigated. Analysis results showed that the lengths of acid-treated NTA became obviously shorter. The diameters of nanotube bundles did not change obviously with acid-treating. Meanwhile, the surface of acid-treated NTA was cross-linked with carboxyl or esterfunction. In addition, acid-treated NTA can catch amino acid residues easily, and then form close combination. PMID:20649031

  5. 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.

  6. Pulse transformer design study

    Microsoft Academic Search

    H. Aslin

    1977-01-01

    This final report describes the design, development of fabrication techniques, fabrication, and testing of two uniform field, air core pulse transformers. The described transformer design minimizes the volume of dielectric material, which provides turn-to-turn insulation, reduces stray series inductance, and thus improves the transformer high frequency response in comparison to conventional pulse transformers. The described pulse transformers are intended for

  7. The protective effects of omega-6 fatty acids in experimental autoimmune encephalomyelitis (EAE) in relation to transforming growth factor-beta 1 (TGF-beta1) up-regulation and increased prostaglandin E2 (PGE2) production.

    PubMed

    Harbige, L S; Layward, L; Morris-Downes, M M; Dumonde, D C; Amor, S

    2000-12-01

    Polyunsaturated fatty acids are known to affect the immune response and administration of the omega-6 fatty acid linoleic acid has been reported to be beneficial in multiple sclerosis (MS) and EAE. In this study we have investigated the effects of oral feeding of plant lipid rich in the omega-6 fatty acid gamma-linolenic acid from Borago officinalis on acute and relapse disease and the immune response in EAE using SJL mice. EAE was induced by an encephalitogenic peptide (92-106) of myelin oligodendrocyte glycoprotein (MOG), and mice were fed the plant lipid daily from 7 days after EAE induction to assess the effects on acute disease and from day 25 to assess the effects on disease relapse. The clinical incidence and histological manifestations of acute EAE, and the clinical relapse phase of chronic relapsing EAE (CREAE) were markedly inhibited by omega-6 fatty acid feeding. A significant increase in the production of TGF-beta1 in response to concanavalin A (Con A) at day 13 and a significant increase in TGF-beta1 and PGE2 to Con A, PPD and MOG peptide (92-106) at day 21 were detected in spleen mononuclear cells from fatty acid-fed mice. There was no difference in interferon-gamma, IL-4 and IL-2 production between the fatty acid-fed and control groups. Significantly higher TGF-beta mRNA expression was found in the spleens of omega-6 fatty acid-fed mice at day 21. There were no differences in spleen cell proliferative response to Con A, PPD and MOG peptide (92-106). Biochemical analysis of spleen cell membrane fatty acids revealed significant increases in the eicosanoid precursor fatty acids dihomo-gamma-linolenic acid and arachidonic acid in response to gamma-linolenic acid feeding, indicating rapid metabolism to longer chain omega-6 fatty acids. These results show that oral feeding of gamma-linolenic acid-rich plant lipid markedly affects the disease course of acute EAE and CREAE and is associated with an increase in cell membrane long chain omega-6 fatty acids, production of PGE2 and gene transcription and, on activation, secretion of TGF-beta1. PMID:11122253

  8. Structural Transformation in Nanophase Titanium Dioxide

    Microsoft Academic Search

    Muying Wu; Weifeng Zhang; Zuliang Du; Yabin Huang

    1999-01-01

    Nanophase TiO2 was prepared by a stearic acid sol-gel technique. X-ray measurements showed that the as-prepared sample is anatase TiO2 phase with an average grain size of 10.4 nm. Raman spectroscopy was used to investigate the structural transformation from anatase-to-rutile in the nanophase TiO2 annealed at a series of temperatures from 450 to 650°C. The results showed that the transformation

  9. Vibrational structure of the polyunsaturated fatty acids eicosapentaenoic acid and arachidonic acid studied by infrared spectroscopy

    NASA Astrophysics Data System (ADS)

    Kiefer, Johannes; Noack, Kristina; Bartelmess, Juergen; Walter, Christian; Dörnenburg, Heike; Leipertz, Alfred

    2010-02-01

    The spectroscopic discrimination of the two structurally similar polyunsaturated C 20 fatty acids (PUFAs) 5,8,11,14,17-eicosapentaenoic acid and 5,8,11,14-eicosatetraenoic acid (arachidonic acid) is shown. For this purpose their vibrational structures are studied by means of attenuated total reflection (ATR) Fourier-transform infrared (FT-IR) spectroscopy. The fingerprint regions of the recorded spectra are found to be almost identical, while the C-H stretching mode regions around 3000 cm -1 show such significant differences as results of electronic and molecular structure alterations based on the different degree of saturation that both fatty acids can be clearly distinguished from each other.

  10. GIS TRANSFORMATIONS Conference Presentation

    E-print Network

    Tobler, Waldo

    GIS TRANSFORMATIONS Conference Presentation Waldo Tobler Geography Department University, line, area, or field phenomena, then the sixteen common classes of transformation are: point -> point (scalar, vector, tensor) data, to obtain eighty distinct possible classes of transformation. The common

  11. Evaluating Transformer Losses

    E-print Network

    Grun, R. L. Jr.

    and replacing them with low loss units. Today few industrials evaluate losses on either power or distribution transformers. TRANSFORMER LOSSES Transformer losses are divided 'nto load losses and no-load losses. Load losses are due to the winding resista... therefore are a function of the load squared. No-load losses occur from energizing the transformer steel and fore are continuous regardless of the transformer load. TRANSFORMER DESIGN Both types of losses are a fun ce here ion of design. If losses...

  12. 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, José 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

  13. Integer lapped biorthogonal transform

    Microsoft Academic Search

    Zhong Guangjun; Cheng Lizhi; Chen Huowang

    2001-01-01

    A type of lapped biorthogonal transform that can map integers to integers is considered. Based on the computational structure of the proposed lapped transform, an efficient multiplierless algorithm for the lapped biorthogonal transform (LBT), called integer lapped biorthogonal transform (IntLBT), is proposed. The proposed IntLBT is implemented by a series of dyadic lifting steps, and provides fast, efficient computation of

  14. transformation languages Introduction

    E-print Network

    Nierstrasz, Oscar

    transformation languages Introduction Transformation languages are widely used for to process can I change / transform the design of a certain task without changing it's logic The common/and hierarchical or/and abstract set of information. It can even be a stream of data. · The transformation engine

  15. 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

  16. Perfect NOT transformation and conjugate transformation

    E-print Network

    Fengli Yan; Ting Gao; Zhichao Yan

    2012-03-15

    The perfect NOT transformation, probabilistic perfect NOT transformation and conjugate transformation are studied. Perfect NOT transformation criteria on a quantum state set $S$ of a qubit are obtained. Two necessary and sufficient conditions for realizing a perfect NOT transformation on $S$ are derived. When these conditions are not satisfied we discuss a probabilistic perfect NOT transformation (gate). We construct a probabilistic perfect NOT machine (gate) by a general unitary-reduction operation. With a postselection of the measurement outcomes, the probabilistic NOT gate yields perfectly complements of the input states. We prove that one can realize probabilistically the NOT gate of the input states secretly chosen from a certain set $S=\\{|\\Psi_1>, |\\Psi_2>,..., |\\Psi_n>\\}$ if and only if $|\\Psi_1>, |\\Psi_2>,...,$ and $|\\Psi_n>$ are linearly independent. We also generalize the probabilistic NOT transformation to the conjugate transformation in the multi-level quantum system. The lower bound of the best possible efficiencies attained by a probabilistic perfect conjugate transformation are obtained.

  17. New graft copolymers of hyaluronic acid and polylactic acid: Synthesis and characterization

    Microsoft Academic Search

    Fabio Salvatore Palumbo; Giovanna Pitarresi; Delia Mandracchia; Giuseppe Tripodo; Gaetano Giammona

    2006-01-01

    New graft copolymers have been synthesized, using hyaluronic acid (HA) as a hydrophilic backbone and polylactic acid (PLA) as an aliphatic polyester in order to obtain new polymeric derivatives of HA able to hydrophobically associate in an aqueous medium. Hyaluronic acid with low molecular weight was made soluble in organic solvent by transformation to its tetrabutylammonium (TBA) salt. Using the

  18. 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.

  19. Human transforming growth factor-beta complementary DNA sequence and expression in normal and transformed cells

    Microsoft Academic Search

    Rik Derynck; Julie A. Jarrett; Ellson Y. Chen; Dennis H. Eaton; John R. Bell; Richard K. Assoian; Anita B. Roberts; Michael B. Sporn; David V. Goeddel

    1985-01-01

    The partial amino-acid sequence of purified human transforming growth factor-beta (TGF-beta) was used to identify a series of cDNA clones encoding the protein. The cDNA sequence indicates that the 112-amino acid monomeric form of the natural TGF-beta homodimer is derived proteolytically from a much longer precursor polypeptide which may be secreted. TGF-beta messenger RNA is synthesized in various normal and

  20. On Poisson Nonlinear Transformations

    PubMed Central

    2014-01-01

    We construct the family of Poisson nonlinear transformations defined on the countable sample space of nonnegative integers and investigate their trajectory behavior. We have proved that these nonlinear transformations are regular. PMID:25136692

  1. The Patch Transform

    E-print Network

    Avidan, Shai

    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 ...

  2. Metrics for enterprise transformation

    E-print Network

    Blackburn, Craig D. (Craig David), S. M. Massachusetts Institute of Technology

    2009-01-01

    The objective of this thesis is to depict the role of metrics in the evolving journey of enterprise transformation. To this end, three propositions are explored: (i) metrics and measurement systems drive transformation, ...

  3. Applying Improved Efficiency Transformers 

    E-print Network

    Haggerty, N. K.; Malone, T. P.

    1998-01-01

    that manufacturers utilize to reduce transformer losses are presented. Investment guidelines are provided for performing an economic evaluation and determining if an improved efficiency transformer can be justified. The decision to spend additional capital dollars...

  4. Discrete radon transform

    Microsoft Academic Search

    GREGORY BEYLKIN

    1987-01-01

    This paper describes the discrete Radon transform (DRT) and the exact inversion algorithm for it. Similar to the discrete Fourier transform (DFT), the DRT is defined for periodic vector-sequences and studied as a transform in its own right. Casting the forward transform as a matrix-vector multiplication, the key observation is that the matrix-although very large-has a block-circulant structure. This observation

  5. The application of Fourier-transform infrared (FTIR) and Raman spectroscopy (FTR) to the evaluation of structural changes in wool fibre keratin after deuterium exchange and modification by the orthosilicic acid

    NASA Astrophysics Data System (ADS)

    Wojciechowska, El?bieta; W?ochowicz, Andrzej; Wysocki, Marian; Pielesz, Anna; Wese?ucha-Birczy?ska, Aleksandra

    2002-09-01

    An injury of hair macrostructure and substantial alkalinity of the water-lipid shield medium on wool fibre surface is conducive to a transition of heavy metal elements into ion forms. It also helps SiO 2 in a transition into a colloidal form of orthosilicic acid and its penetration in this form of the wool fibre structure. Consequently, it leads to the biomineralization of the wool fibre [J. Mol. Struct. 511-512 (1999) 307; J. Mol. Struct. 511-512 (2000) 397]. Changes taking place in the process of biomineralization, mainly in the amorphous region, may be responsible for the effectiveness of the technological processes and the properties of ready wool products [3]. Wool fibres obtained from Polish Merino sheep were treated with solution of orthosilicic acid (H 4SiO 4· nH 2O) in experimental conditions during which fibres first underwent extraction with methylene chloride and them with asolution of orthosilicic acid in alkaline medium. Studies of deuterium exchange in the wool fibre keratin were applied to study changes in the structure of wool fibre keratin in the process of orthosilicic acid treatment. The changes in the structure of wool fibre were studied by means of infrared spectroscopy (FTIR) and Raman spectroscopy (FTR).

  6. The pulse sorting transform

    Microsoft Academic Search

    K. C. Overman; D. F. Mix; J. A. Lookadoo

    1990-01-01

    A modification of conventional Fourier transforms is presented. This modification is called the pulse sorting transform (PST) and is useful in extracting information from signals comprised of interleaved pulse trains. A brief derivation of the PST from the conventional transform is presented, followed by theorems that describe the PST's properties. Several examples of how the PST can be an effective

  7. 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…

  8. The Transformation of Suffering

    Microsoft Academic Search

    Liza J. Rankow

    2006-01-01

    This article offers reflections on The Passion of the Lord, edited by James A. Noel and Matthew V. Johnson. The title “The Transformation of Suffering” refers not only to the transformations emerging from the epic suffering endured by Jesus and by peoples of the African diaspora, but to the ways each of us may be spiritually transformed by the crucible

  9. LAPPED TRANSFORMS COMPRESSION

    E-print Network

    de Queiroz, Ricardo L.

    Chapter 6 LAPPED TRANSFORMS FOR IMAGE COMPRESSION Ricardo L. de Queiroz Digital Imaging Technology aspects of lapped transforms and their applications to image compression. It is a subject that has been extensively studied mainly because lapped transforms are closely related to filter banks, wavelets, and time

  10. Transformations - Composition (NLVM)

    NSDL National Science Digital Library

    2011-01-01

    This Java applet enables learners to explore compositions of two transformations (among sliding, flipping and turning) both informally and within a coordinate system. Students select and compose shapes and manipulate the transformations to see the effect on a transformed image. Links to instructions, activities and teacher/parent information are included.

  11. Environmental transformation mechanisms of thiodiglycol

    SciTech Connect

    Lee, K.P.; Allen, H.E. [Univ. of Delaware, Newark, DE (United States). Dept. of Civil and Environmental Engineering

    1998-09-01

    The fate of thiodiglycol (TDG) in environmental samples was studied through analysis of batch solid-solution suspensions. The authors monitored aqueous-phase TDG concentrations and thiodiglycolic acid (TGDA) concentrations by high-performance liquid chromatography with ultraviolet detection. They investigated TDG and TDGA sorption to six soils. Thiodiglycol sorption was insignificant, with a maximum sorption capacity of less than 10 mg/kg. Sorption of TDGA varied, with maximum sorption capacities ranging from 19.9 to 427.4 mg/kg. Photolysis, hydrolysis, and the presence of iron oxide and aluminum oxide had little effect on the fate of TDG and TDGA. However, manganese oxide sorbed TDG and was pH dependent. Biological transformation of TDG to TDGA, with the formation of [(2-hydroxyethyl)thio]acetic acid (TDGMA) as an intermediate, occurred with zero-order rate coefficients ranging from 0 to 6.26 {times} 10{sup {minus}6} mol/L{center_dot}h{sup {minus}1}. Biological toxins hindered this transformation. The major process affecting TDG was biotransformation to form TDGMA and subsequently its biotransformation to TDGA.

  12. 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)

  13. Invertible Darboux Transformations

    E-print Network

    Ekaterina Shemyakova

    2013-01-04

    For operators of many different kinds it has been proved that (generalized) Darboux transformations can be built using so called Wronskian formulae. Such Darboux transformations are not invertible in the sense that the corresponding mappings of the operator kernels are not invertible. The only known invertible ones were Laplace transformations (and their compositions), which are special cases of Darboux transformations for hyperbolic bivariate operators of order 2. In the present paper we find a criteria for a bivariate linear partial differential operator of an arbitrary order d to have an invertible Darboux transformation. We show that Wronkian formulae may fail in some cases, and find sufficient conditions for such formulae to work.

  14. Dietary docosahexaenoic acid ameliorates, but rapeseed oil and safflower oil accelerate renal injury in stroke-prone spontaneously hypertensive rats as compared with soybean oil, which is associated with expression for renal transforming growth factor-?, fibronectin and renin

    Microsoft Academic Search

    Makoto Miyazaki; Naoya Takemura; Shiro Watanabe; Noriaki Hata; Yoshihisa Misawa; Harumi Okuyama

    2000-01-01

    We have noted that n–3 fatty acid-rich oils, such as fish oil, perilla oil and flaxseed oil as well as ethyl docosahexaenoate (DHA) prolonged the survival time of stroke-prone spontaneously hypertensive rats (SHRSP) rats by ?10% as compared with linoleate (n–6)-rich safflower oil. Rapeseed oil with a relatively low n–6\\/n–3 ratio unusually shortened the survival time by ?40%, suggesting the

  15. Importance of matrix: Analyte ratio for buffer tolerance using 2,5-dihydroxybenzoic acid as a matrix in matrix-assisted laser desorption\\/ionization-fourier transform mass spectrometry and matrix-assisted laser desorption\\/ionization-time of flight

    Microsoft Academic Search

    Jie Yao; Jill R. Scott; Mary K. Young; Charles L. Wilkins

    1998-01-01

    Many biological samples destined for matrix-assisted laser desorption\\/ionization mass spectrometry (MALDI-MS) contain buffers.\\u000a The presence of these buffers often inhibits the ability to obtain spectra. Here, the results of a study of the effects of\\u000a six different buffers on spectra of three representative small proteins are reported utilizing 2,5-dihydroxybenzoic acid as\\u000a matrix. These proteins, bovine insulin, cytochrome c, and bovine

  16. The effects of pH, ionic strength, and iron–fulvic acid interactions on the kinetics of non-photochemical iron transformations. I. Iron(II) oxidation and iron(III) colloid formation

    Microsoft Academic Search

    Michael J. Pullin; Stephen E. Cabaniss

    2003-01-01

    Flow injection analysis was used to study the effect of a fulvic acid on the kinetics of iron(II) oxidation and iron colloid formation under conditions approximating fresh natural waters. While iron(II) oxidation in high-carbonate inorganic solutions is predicted well by a recently proposed homogeneous model, it overestimates the oxidation rate in low-carbonate solutions, possibly due to the formation of an

  17. Inhibition of cellular transformation by berry extracts.

    PubMed

    Xue, H; Aziz, R M; Sun, N; Cassady, J M; Kamendulis, L M; Xu, Y; Stoner, G D; Klaunig, J E

    2001-02-01

    Recent studies have examined and demonstrated the potential cancer chemopreventive activity of freeze-dried berries including strawberries and black raspberries. Although ellagic acid, an abundant component in these berries, has been shown to inhibit carcinogenesis both in vivo and in vitro, several studies have reported that other compounds in the berries may also contribute to the observed inhibitory effect. In the present study, freeze-dried strawberries (Fragara ananassa, FA) or black raspberries (Rubus ursinus, RU) were extracted, partitioned and chromatographed into several fractions (FA-F001, FA-F003, FA-F004, FA-F005, FA-DM, FA-ME from strawberries and RU-F001, RU-F003, RU-F004, RU-F005, RU-DM, RU-ME from black raspberries). These extracts, along with ellagic acid, were analyzed for anti-transformation activity in the Syrian hamster embryo (SHE) cell transformation model. None of the extracts nor ellagic acid by themselves produced an increase in morphological transformation. For assessment of chemopreventive activity, SHE cells were treated with each agent and benzo[a]pyrene (B[a]P) for 7 days. Ellagic acid, FA-ME and RU-ME fractions produced a dose-dependent decrease in transformation compared with B[a]P treatment only, while other fractions failed to induce a significant decrease. Ellagic acid, FA-ME and RU-ME were further examined using a 24 h co-treatment with B[a]P or a 6 day treatment following 24 h with B[a]P. Ellagic acid showed inhibitory ability in both protocols. FA-ME and RU-ME significantly reduced B[a]P-induced transformation only when co-treated with B[a]P for 24 h. These results suggest that a methanol extract from strawberries and black raspberries may display chemopreventive activity. The possible mechanism by which these methanol fractions (FA-ME, RU-ME) inhibited cell transformation appear to involve interference of uptake, activation, detoxification of B[a]P and/or intervention of DNA binding and DNA repair. PMID:11181460

  18. Galectin-1 binds oncogenic H-Ras to mediate Ras membrane anchorage and cell transformation

    Microsoft Academic Search

    Ariella Paz; Roni Haklai; Galit Elad-Sfadia; Eyal Ballan; Yoel Kloog

    2001-01-01

    Ras genes, frequently mutated in human tumors, promote malignant transformation. Ras transformation requires membrane anchorage, which is promoted by Ras farnesylcysteine carboxymethylester and by a second signal. Previously we showed that the farnesylcysteine mimetic, farnesylthiosalicylic acid (FTS) disrupts Ras membrane anchorage. To understand how this disruption contributes to inhibition of cell transformation we searched for new Ras-interacting proteins and identified

  19. Advanced chemical mechanisms for acid deposition modeling

    Microsoft Academic Search

    W. R. Stockwell; X. Tang

    1987-01-01

    Atmospheric chemistry is of concern to both policy-makers and scientists because atmospheric transformation rates determine the extent to which reductions in the emissions of sulfur and nitrogen oxides will in fact reduce acid deposition. Policy decisions should be based upon solid science, thus a chemical mechanism for a regional acid deposition model must incorporate all significant chemical reactions. The gas-phase

  20. Geophysical images of the Dead Sea Transform in Jordan reveal an impermeable barrier for fluid flow

    NASA Astrophysics Data System (ADS)

    DESERT Research Group,; Ritter, O.; Ryberg, T.; Weckmann, U.; Hoffmann-Rothe, A.; Abueladas, A.; Garfunkel, Z.

    2003-07-01

    High-resolutionseismictomography and magneto-telluric (MT) soundings of the shallow crust show strong changes in material properties across the Dead Sea Transform Fault (DST) in the Arava valley in Jordan. 2D inversion results of the MT data indicate that the DST is associated with a strong lateral conductivity contrast of a highly conductive layer at a depth of approximately 1.5 km cut-off at a position coinciding with the surface trace of the DST. At the same location, we observe a sharp increase of P wave velocities from <4 km/s west of the fault to >5 km/s to the east. The high velocities in the east probably reflect Precambrian rocks while the high electrical conductivity west of the DST is attributed to saline fluids within the sedimentary filling. In this sense, the DST appears to act as an impermeable barrier between two different rock formations. Such a localized fluid barrier is consistent with models of fault zone evolution but has so far not been imaged by geophysical methods. The situation at the DST is remarkably different from active segments of the San Andreas Fault which typically show a conductive fault core acting as a fluid conduit.

  1. Nanosecond Pulse Transformers

    Microsoft Academic Search

    C. Norman Winningstad

    1959-01-01

    The transmission-line approach to the design of transformers yields a unit with no first-order rise-time limit since this approach uses distributed rather than lumped constants. The total time delay through the transmission-line-type transformer may exceed the rise time by a large factor, unlike conventional transformers. The extra winding length can be employed to improve the low-frequency response of the unit.

  2. Secoiridoids and antifungal aromatic acids from Gentiana algida

    Microsoft Academic Search

    R. X. Tan; J.-L. Wolfender; W. G. Ma; L. X. Zhang; K. Hostettmann

    1996-01-01

    Fractionation of an aqueous acetone extract of the whole herb of Gentiana algida gave one new [2?-(o,m-dihydroxybenzyl)sweroside] and five known secoiridoids, together with anofinic acid, fomannoxin acid, sitosterol, daucosterol, stigmasterol, oleanolic acid, orientin and gentianose. The structures were determined by spectral methods and a few chemical transformations. Anofinic acid and fomannoxin acid were found to be active against Cladosporium cucumerinum,

  3. Aristolochic Acids

    MedlinePLUS

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

  4. Evaluating Transformer Losses 

    E-print Network

    Grun, R. L. Jr.

    1989-01-01

    and replacing them with low loss units. Today few industrials evaluate losses on either power or distribution transformers. TRANSFORMER LOSSES Transformer losses are divided 'nto load losses and no-load losses. Load losses are due to the winding resista... of the transformer. It will vary between the limits of the load factor and the square of the load factor, depending upon the shape of the load curve. For a load factor of .80, the loss factor will be between .64 and .80. The yearly no-load loss value...

  5. Transform coding of images

    NASA Astrophysics Data System (ADS)

    Clarke, R. J.

    The theoretical and practical aspects of transform coding systems for processing still or moving images are discussed. Among the specific topics considered are: the statistical properties of images; orthogonal transforms for image coding; and transform coefficient quantization and bit allocation. Some practical methods of image coding are described, including: interframe coding; intraframe coding; and transform coding of color data. The application of human visual models to the assessment of image quality is also discussed. Techniques for measuring rms error in coded images are given in an appendix.

  6. Spherical Harmonic Transform Algorithms

    SciTech Connect

    Drake, John B [ORNL; Worley, Patrick H [ORNL; D'Azevedo, Eduardo [ORNL

    2008-01-01

    A collection of MATLAB classes for computing spherical harmonic transforms are presented and used to solve simple partial differential equations on the sphere. The spectral synthesis and analysis using fast Fourier transforms and Legendre transforms with the associated Legendre functions are presented in depth. A set of methods associated with a spectral\\_field class provides spectral approximation to the $\\DIV$, $\\CURL$, $\\GRAD$, and $\\LAPL$ in spherical geometr y. Laplace inversion and Helmholtz equation solvers are also methods for this clas s. Investigation of algorithms and analysis for spherical harmonic transform optio ns for parallel high performance computers are discussed in the context of global climate and weather models.

  7. 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...

  8. Dietary docosahexaenoic acid ameliorates, but rapeseed oil and safflower oil accelerate renal injury in stroke-prone spontaneously hypertensive rats as compared with soybean oil, which is associated with expression for renal transforming growth factor-beta, fibronectin and renin.

    PubMed

    Miyazaki, M; Takemura, N; Watanabe, S; Hata, N; Misawa, Y; Okuyama, H

    2000-01-01

    We have noted that n-3 fatty acid-rich oils, such as fish oil, perilla oil and flaxseed oil as well as ethyl docosahexaenoate (DHA) prolonged the survival time of stroke-prone spontaneously hypertensive rats (SHRSP) rats by approximately 10% as compared with linoleate (n-6)-rich safflower oil. Rapeseed oil with a relatively low n-6/n-3 ratio unusually shortened the survival time by approximately 40%, suggesting the presence of minor components unfavorable to SHRSP rats. This study examined the effects of dietary oils and DHA on renal injury and gene expression related to renal injury in SHRSP rats. Rats fed rapeseed oil- and safflower oil-supplemented diets developed more severe proteinuria than those fed soybean oil-supplemented diet used as a control, but there were no significant differences in blood pressure. In contrast, the DHA-supplemented diet inhibited the development of proteinuria and suppressed hypertension. The mRNA levels for renal TGF-beta, fibronectin and renin were higher in the rapeseed oil and safflower oil groups after 9 weeks of feeding of the experimental diet than in the soybean oil and DHA groups. The fatty acid composition of kidney phospholipids was markedly affected by these diets. These results indicate that the renal injury observed in the groups fed safflower oil with a high n-6/n-3 ratio and rapeseed oil with presumed minor components is accompanied by increased expression of the TGF-beta, renin and fibronectin genes, and that dietary DHA suppresses renal injury and gene expression as compared with soybean oil. PMID:10601699

  9. Pattern Transformation with DNA Circuits

    PubMed Central

    Chirieleison, Steven M.; Allen, Peter B.; Simpson, Zack B.; Ellington, Andrew D.; Chen, Xi

    2014-01-01

    Readily programmable chemical networks are important tools as the scope of chemistry expands from individual molecules to larger molecular systems. While many complex systems have been constructed using conventional organic and inorganic chemistry, the programmability of biological molecules such as nucleic acids allows for precise, high-throughput, and automated design, as well as simple, rapid, and robust implementation. Here we show that systematic and quantitative control over the diffusivity and reactivity of DNA molecules yields highly programmable chemical reaction networks (CRNs) that execute at the macroscale. In particular, we design and implement non-enzymatic DNA circuits capable of performing pattern transformation algorithms such as edge detection. We also show that it is possible to fine-tune and multiplex such circuits. We believe these strategies will provide programmable platforms for prototyping CRNs, for discovering bottom-up construction principles, and for generating patterns in materials. PMID:24256862

  10. The Discrete Pulse Transform

    Microsoft Academic Search

    C. H. Rohwer; D. P. Laurie

    2006-01-01

    We investigate a recent algorithm, here called a discrete pulse transform (DPT), for the multiresolution analysis of a sequence. A DPT represents a sequence as a sum of pulses, where a pulse is a sequence which is zero everywhere except for a certain number of consecutive elements which have a constant nonzero value. Unlike the discrete Fourier and wavelet transforms,

  11. Direct current transformer

    NASA Technical Reports Server (NTRS)

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

    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.

  12. Lapped Tight Frame Transforms

    Microsoft Academic Search

    Amina Chebira; J. Kovacevic

    2007-01-01

    We propose a new class of equal-norm tight frames termed lapped tight frame transforms (LTFTs). These can be seen as a redundant counterpart to bases known as lapped orthogonal transforms (LOTs) introduced by Malvar and Cassereau, as well as an infinite-dimensional counterpart to harmonic tight frames (HTFs). To construct LTFTs, we seed them from LOTs and show that, in a

  13. 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.

  14. 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.

  15. 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.

  16. The generalized Gabor transform.

    PubMed

    Yao, J; Krolak, P; Steele, C

    1995-01-01

    The generalized Gabor transform (for image representation) is discussed. For a given function f(t), tinR, the generalized Gabor transform finds a set of coefficients a(mr) such that f(t)=Sigma(m=-infinity)(infinity)Sigma (r=-infinity)(infinity)alpha(mr )g(t-mT)exp(i2pirt/T'). The original Gabor transform proposed by D. Gabor (1946) is the special case of T=T'. The computation of the generalized Gabor transform with biorthogonal functions is discussed. The optimal biorthogonal functions are discussed. A relation between a window function and its optimal biorthogonal function is presented based on the Zak (1967) transform when T/T' is rational. The finite discrete generalized Gabor transform is also derived. Methods of computation for the biorthogonal function are discussed. The relation between a window function and its optimal biorthogonal function derived for the continuous variable generalized Gabor transform can be extended to the finite discrete case. Efficient algorithms for the optimal biorthogonal function and generalized Gabor transform for the finite discrete case are proposed. PMID:18290047

  17. Light Controlled Piezoelectric Transformer

    Microsoft Academic Search

    Lucjan Kozielski

    2011-01-01

    The author designed ``smart material'' device allow to control an output voltage level by change of incident light intensity. New functions of piezoelectric transformer (PT) was realized by superimposing piezoelectricity with photostriction. The effect of a light influence on the PT voltage gain was proved experimentally, consequently these ``smart'' transformers with its new functionality can be utilized as a promising

  18. Exploring Functional Mellin Transforms

    E-print Network

    J. LaChapelle

    2015-01-08

    We define functional Mellin transforms within a scheme for functional integration proposed in [1]. Functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

  19. Power transformer testing

    NASA Astrophysics Data System (ADS)

    Zagrobelna, Magdalena; Wasilewski, Andrzej

    2014-11-01

    This paper presents the method of oil-filled transformer monitoring by means of a fiber optic sensor. Our method can be extremely useful in case of prevent overheating and the winding failure. A special semiconductor technology plays an important role in such measurement. The tests were carried out by means of the developed test stand imitating a real power transformer.

  20. Transform picture coding

    Microsoft Academic Search

    P. A. Wintz

    1972-01-01

    Picture coding by first dividing the picture into sub-pictures and then performing a linear transformation on each sub-picture cud quantizing and coding the resulting coefficients is introduced from a heuristic point of view. Various transformation, quantization, and coding strategies are discussed. A survey of all known applications of these techniques to monochromatic image coding is presented along with a summary

  1. Program Transformation Mechanics A Classification of Mechanisms for Program Transformation

    E-print Network

    Utrecht, Universiteit

    Program Transformation Mechanics A Classification of Mechanisms for Program Transformation with a Survey of Existing Transformation Systems Jonne van Wijngaarden Eelco Visser UU-CS-2003-048 Institute Transformation Mechanics A Classification of Mechanisms for Program Transformation with a Survey of Existing

  2. Logarithmic transformation of response Logarithmic transformation of response

    E-print Network

    Komarek, Arnost

    Logarithmic transformation of response Logarithmic transformation of response Often, support S of Y is S = (0, ). Logarithm is then one of transformations to consider when trying to obtain a correct (wrong. Model Building 1. Transformation of response #12;Logarithmic transformation of response When does

  3. 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

  4. Rosmarinic acid.

    PubMed

    Petersen, Maike; Simmonds, Monique S J

    2003-01-01

    Rosmarinic acid is an ester of caffeic acid and 3,4-dihydroxyphenyllactic acid. It is commonly found in species of the Boraginaceae and the subfamily Nepetoideae of the Lamiaceae. However, it is also found in species of other higher plant families and in some fern and hornwort species. Rosmarinic acid has a number of interesting biological activities, e.g. antiviral, antibacterial, antiinflammatory and antioxidant. The presence of rosmarinic acid in medicinal plants, herbs and spices has beneficial and health promoting effects. In plants, rosmarinic acid is supposed to act as a preformed constitutively accumulated defence compound. The biosynthesis of rosmarinic acid starts with the amino acids L-phenylalanine and L-tyrosine. All eight enzymes involved in the biosynthesis are known and characterised and cDNAs of several of the involved genes have been isolated. Plant cell cultures, e.g. from Coleus blumei or Salvia officinalis, accumulate rosmarinic acid in amounts much higher than in the plant itself (up to 36% of the cell dry weight). For this reason a biotechnological production of rosmarinic acid with plant cell cultures has been proposed. PMID:12482446

  5. Motion estimation using lapped transforms

    Microsoft Academic Search

    Robert W. Young; Nick G. Kingsbury

    1992-01-01

    A frequency-domain algorithm for motion estimation based on overlapped transforms of the image data is developed. The transform used is referred to as the complex lapped transform (CLT) and is formed by extending the lapped orthogonal transform to have complex basis functions. It may also be viewed as a modified short time Fourier transform. A method for estimating cross-correlation functions

  6. Lapped transforms for efficient transform\\/subband coding

    Microsoft Academic Search

    H. S. Malvar

    1990-01-01

    Two lapped transforms for subband\\/transform coding of signals are introduced: a version of the lapped orthogonal transform (LOT), which can be efficiently computed for any transform length; and the modulated lapped transform (MLT), which is based on a modulated quadrature mirror (QMF) bank. The MLT can also be efficiently computed by means of a type-IV discrete sine transform (DST-IV). The

  7. Lapped directional transform: a new transform for spectral image analysis

    Microsoft Academic Search

    Dietmar Kunz; Til Aach

    1999-01-01

    We propose a new real-valued lapped transform for 2D-signal and image processing. Lapped transforms are particularly useful in block-based processing, since their intrinsically overlapping basis functions reduce or prevent block artifacts. Our transform is derived from the modulated lapped transform (MLT), which, as a real-valued and separable transform like the discrete cosine transform, does not allow to unambiguously identify oriented

  8. Lorentz transformation by mimicking the Lorentz transformation

    E-print Network

    Bernhard Rothenstein; Stefan Popescu

    2007-09-24

    We show that starting with the fact that special relativity theory is concerned with a distortion of the observed length of a moving rod, without mentioning if it is a "contraction" or "dilation", we can derive the Lorentz transformations for the spacetime coordinates of the same event. This derivation is based on expressing the length of the moving rod as a sum of components with all the lengths involved in this summation being measured by the observers of the same inertial reference frame.

  9. 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.

  10. 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).

  11. Basically Acids

    NSDL National Science Digital Library

    University of Houston,

    Students learn the basics of acid/base chemistry in a fun, interactive way by studying instances of acid/base chemistry found in popular films such as Harry Potter and the Prisoner of Azkaban and National Treasure. Students learn what acids, bases and indicators are and how they can be used, including invisible ink. They also learn how engineers use acids and bases every day to better our quality of life. Students' interest is piqued by the use of popular culture in the classroom.

  12. Expression of messenger ribonucleic acid and presence of immunoreactive proteins for epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha) and EGF/TGF alpha receptors and 125I-EGF binding sites in human fallopian tube.

    PubMed

    Chegini, N; Zhao, Y; McLean, F W

    1994-05-01

    Reverse transcription polymerase chain reaction (RT-PCR) revealed that the Fallopian tubes express epidermal growth factor (EGF), transforming growth factor (TGF alpha), and EGF receptor (EGF-R) mRNA. The RT-PCR product was verified by restriction enzyme digestion analysis. Immunohistochemically, EGF, TGF alpha, and EGF-R were localized in Fallopian tubes by use of specific antibodies to human EGF, mature fragments of human TGF alpha, and monoclonal antibodies to the extracellular binding domain of EGF-R. The tubal epithelial cells were the primary site of immunoreactive EGF, TGF alpha, and EGF-R, which were present to a lesser extent in the stromal cells, smooth muscle cell layers, fibroblasts of serosal tissue, and arterial endothelial and smooth muscle cells. Using antibodies generated against the amino and carboxy termini of TGF alpha precursor produced a similar cellular distribution to that observed for mature TGF alpha. The intensity of immunoreactive TGF alpha with these antibodies was similar to that seen with EGF. The ciliated and nonciliated epithelial cells in the ampullary and isthmus regions immunostained with similar intensity for EGF, TGF alpha, and EGF-R. The immunostaining for EGF, TGF alpha, and EGF-R was cycle-dependent, was considerably higher during late proliferative and early-to-mid-secretory phases than during early proliferative and late secretory phases of the menstrual cycle, and was reduced during the postmenopausal period. Specimens obtained 5-12 yr after tubal ligation immunostained for EGF, TGF alpha, and EGF-R similarly to sections from unligated tubes taken during the same phase of the cycle. Quantitative autoradiography of 125I-EGF binding generated a pattern similar to that of immunostaining for EGF-R binding. Net grain density/100 microns 2 calculated for different cell types indicated that the epithelial cells had a significantly higher grain density than did other tubal cell types (p < 0.05) without the cycle dependency seen in the immunohistochemical study. In summary, the results demonstrate that the human Fallopian tube expresses mRNA and contains immunoreactive proteins for EGF, TGF alpha, and EGF-R as well as binding sites for 125I-EGF. The cycle dependency and lower immunostaining in postmenopausal tubes suggest a potential regulation of their expression by ovarian steroids. The results imply the importance of EGF/TGF alpha in a variety of tubal biochemical and physiological functions and possibly early embryonic development. PMID:8025160

  13. 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.

  14. 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)

  15. The Quantum Mellin transform

    E-print Network

    J. Twamley; G. J. Milburn

    2007-02-12

    We uncover a new type of unitary operation for quantum mechanics on the half-line which yields a transformation to ``Hyperbolic phase space''. We show that this new unitary change of basis from the position x on the half line to the Hyperbolic momentum $p_\\eta$, transforms the wavefunction via a Mellin transform on to the critial line $s=1/2-ip_\\eta$. We utilise this new transform to find quantum wavefunctions whose Hyperbolic momentum representation approximate a class of higher transcendental functions, and in particular, approximate the Riemann Zeta function. We finally give possible physical realisations to perform an indirect measurement of the Hyperbolic momentum of a quantum system on the half-line.

  16. 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)

  17. Fourier transform mass spectrometry.

    PubMed

    Scigelova, Michaela; Hornshaw, Martin; Giannakopulos, Anastassios; Makarov, Alexander

    2011-07-01

    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

  18. Series Transmission Line Transformer

    DOEpatents

    Buckles, Robert A. (Livermore, CA); Booth, Rex (Livermore, CA); Yen, Boris T. (El Cerrito, CA)

    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.

  19. 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.

  20. Spherical Wavelet Transform

    Microsoft Academic Search

    Milton Ferreira

    2008-01-01

    .  In this article we present a group-theoretical approach for the continuous wavelet transform (CWT) on the unit sphere S\\u000a \\u000a n-1 based on its conformal group, the Lorentz group Spin(1, n), which is a double covering of the SO(1, n) group. We introduce transformations on the unit sphere from the decomposition of the conformal group into the maximal compact\\u000a subgroup of

  1. Transformation of Yeast

    Microsoft Academic Search

    Albert Hinnen; James B. Hicks; Gerald R. Fink

    1978-01-01

    A stable leu2- yeast strain has been transformed to LEU2+ by using a chimeric ColE1 plasmid carrying the yeast leu2 gene. We have used recently developed hybridization and restriction endonuclease mapping techniques to demonstrate directly the presence of the transforming DNA in the yeast genome and also to determine the arrangement of the sequences that were introduced. These studies show

  2. Functional Mellin Transforms

    E-print Network

    J. LaChapelle

    2015-01-07

    Functional integrals are defined in terms of locally compact topological groups and their associated Banach-valued Haar integrals. This approach generalizes the functional integral scheme of Cartier and DeWitt-Morette. The definition allows a construction of functional Mellin transforms. In turn, the functional Mellin transforms can be used to define functional traces, logarithms, and determinants. The associated functional integrals are useful tools for probing function spaces in general and $C^\\ast$-algebras in particular. Several interesting aspects are explored.

  3. Effect of acidic seed on biogenic secondary organic aerosol growth

    NASA Astrophysics Data System (ADS)

    Czoschke, Nadine M.; Jang, Myoseon; Kamens, Richard M.

    Secondary organic aerosol (SOA) growth in the presence of acid aerosols was studied in twin 500 l Teflon bags and in a 4 m flow reactor. In Teflon bags, isoprene, acrolein and ?-pinene were all made to react individually with ozone and exposed to either acid or non-acid inorganic seed aerosols to determine the effect of acid-catalyzed heterogeneous reactions on SOA growth. ?-Pinene and ozone were made to react in a flow reactor to assess the immediate effect of mixing an acid aerosol with SOA at high and low relative humidity levels. In all cases, exposure to acid seed aerosol increased the amount of SOA mass produced. Fourier transform infrared spectra of the SOA in acid systems confirmed the transformation of carbonyl functional groups through acid-catalyzed heterogeneous reactions when SOAs formed in acidic environments or were exposed to acidic aerosols. Organic products initially produced from ozonation in the gas phase partition onto the inorganic seed aerosol and react heterogeneously with an acid catalyst forming low vapor pressure products. These acid-catalyzed heterogeneous reactions are implicated in generating the increased SOA mass observed in acidic aerosol systems as they transform predominantly gas phase compounds of high volatility into low vapor pressure predominantly particle phase products.

  4. Platelet-derived growth factor is structurally related to the putative transforming protein p28sis of simian sarcoma virus

    Microsoft Academic Search

    Michael D. Waterfield; Geoffrey T. Scrace; Nigel Whittle; Paul Stroobant; Ann Johnsson; Åke Wasteson; Bengt Westermark; Carl-Henrik Heldin; Jung San Huang; Thomas F. Deuel

    1983-01-01

    A partial amino acid sequence of human platelet-derived growth factor, the major mitogen in serum for cells of mesenchymal origin, has been determined. A region of 104 contiguous amino acids shows virtual identity with the predicted sequence of p28sis, the putative transforming protein of simian sarcoma virus (SSV). This similarity suggests a mechanism for transformation by SSV and other agents,

  5. Acid test

    NSDL National Science Digital Library

    Olivia Worland (Purdue University; Biological Sciences)

    2008-06-06

    Baking soda can be used as an indicator of how much acid a substance contains. Lemons and limes have more acid in them than grapefruits and oranges. Indophenol can be used as an indicator of how much vitamin C is in a substance.

  6. Acids (GCMP)

    NSDL National Science Digital Library

    Acids: this is a resource in the collection "General Chemistry Multimedia Problems". We will observe the reaction of sodium bicarbonate with three acid solutions. General Chemistry Multimedia Problems ask students questions about experiments they see presented using videos and images. The questions asked apply concepts from different parts of an introductory course, encouraging students to decompartmentalize the material.

  7. Domoic Acid

    NSDL National Science Digital Library

    Bailey, Christina

    This online student report discusses the chemistry of domoic acid, a biotoxin that is produced by the diatom Psuedo-nitzschia and associated with Amnesiac Shellfish Poisoning (ASP). In addition to a descriptive summary and images, the report links to other areas of interest related to domoic acid poisoning including signs and symptoms, modes of action, and treatment.

  8. Acid rain

    SciTech Connect

    White, J.C. (Cornell University, Ithaca, NY (US))

    1988-01-01

    This book presents the proceedings of the third annual conference sponsored by the Acid Rain Information Clearinghouse (ARIC). Topics covered include: Legal aspects of the source-receptor relationship: an energy perspective; Scientific uncertainty, agency inaction, and the courts; and Acid rain: the emerging legal framework.

  9. Acid Rain

    Microsoft Academic Search

    Gene E. Likens; Richard F. Wright; James N. Galloway; Thomas J. Butler

    1979-01-01

    Measurements of the acidity of rain and snow reveal that in parts of the eastern U.S. and of western Europe precipitation has changed from a nearly neutral solution 200 years ago to a dilute solution of sulfuric and nitric acids today. The trend is a result of the emission of sulfur and nitrogen oxides to the atmosphere accompanying the rise

  10. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

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

  11. Acid Precipitation

    NSDL National Science Digital Library

    Tyser, Jim

    Acid precipitation will be defined. At different points in the lesson students will write balanced reactions for the formation acid precipitation from atmospheric sulfur and nitrogen oxides and the neutralization of acids by limestone. Students will determine which states are most at risk from acid precipitation and assess how that risk has changed from 1996 to 2006. Sources of atmospheric sulfur (burning of high-sulfur coal) and nitrogen oxides (automobile exhaust) will be listed. The buffering effect of limestone soils and its mitigating effect on acid precipitation will be discussed. Students will correlate these areas with sulfur and nitrogen oxide production, population, composition of coal fields, and soil composition. This resource includes both a teaching guide and student worksheets.

  12. Asparagusic acid.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2014-01-01

    Asparagusic acid (1,2-dithiolane-4-carboxylic acid) is a simple sulphur-containing 5-membered heterocyclic compound that appears unique to asparagus, though other dithiolane derivatives have been identified in non-food species. This molecule, apparently innocuous toxicologically to man, is the most probable culprit responsible for the curious excretion of odorous urine following asparagus ingestion. The presence of the two adjacent sulphur atoms leads to an enhanced chemical reactivity, endowing it with biological properties including the ability to substitute potentially for ?-lipoic acid in ?-keto-acid oxidation systems. This brief review collects the scattered data available in the literature concerning asparagusic acid and highlights its properties, intermediary metabolism and exploratory applications. PMID:24099657

  13. A two-step bioconversion process for vanillin production from ferulic acid combining Aspergillus niger and Pycnoporus cinnabarinus

    Microsoft Academic Search

    Laurence Lesage-Meessen; Michel Delattre; Mireille Haon; Jean-François Thibault; Benoit Colonna Ceccaldi; Pascal Brunerie; Marcel Asther

    1996-01-01

    A two-step bioconversion process of ferulic acid to vanillin was elaborated combining two filamentous fungi, Aspergillus niger and Pycnoporus cinnabarinus. In the first step, A. niger transformed ferulic acid to vanillic acid and in the second step vanillic acid was reduced to vanillin by P. cinnabarinus. Ferulic acid metabolism by A. niger occurred essentially via the propenoic chain degradation to

  14. Inversion of k-Plane Transforms via Continuous Wavelet Transforms

    Microsoft Academic Search

    B Rubin

    1998-01-01

    The inversion formulae fork-plane transforms of functionsf?Lp(Rn) are obtained in terms of continuous wavelet transforms generated by a wavelet measure. The admissibility conditions for a wavelet measure ? are formulated in terms of the Fourier transform of ? and without using the Fourier transform. The investigation is based on the wavelet type representations of Riesz fractional derivatives.

  15. APPENDIX F. TRANSFORMS, COMPLEX ANALYSIS 1 Transforms, Complex

    E-print Network

    Callen, James D.

    APPENDIX F. TRANSFORMS, COMPLEX ANALYSIS 1 Appendix F Transforms, Complex Analysis This appendix discusses Fourier and Laplace transforms as they are used in plasma physics and this book. Also, key properties of complex variable theory that are needed for understanding and inverting these transforms

  16. Optical transformation from chirplet to fractional Fourier transformation kernel

    E-print Network

    Hong-yi Fan; Li-yun Hu

    2009-02-11

    We find a new integration transformation which can convert a chirplet function to fractional Fourier transformation kernel, this new transformation is invertible and obeys Parseval theorem. Under this transformation a new relationship between a phase space function and its Weyl-Wigner quantum correspondence operator is revealed.

  17. From transformation traces to transformation rules: Assisting Model Driven Engineering

    E-print Network

    Paris-Sud XI, Université de

    From transformation traces to transformation rules: Assisting Model Driven Engineering approach. In this paper we are interested in semi-automatically gen- erating labelled graph (model) transformations conform to a particu- lar syntax (meta-model). Those transformations are basic operations in model driven

  18. Laplace Transforms An integral transform is an operator

    E-print Network

    Ikenaga, Bruce

    9­28­1998 Laplace Transforms An integral transform is an operator F (s) = Z b a K(s; t)f(t) dt: The input to the transform is the function f(t); the output is the function F (s). (By convention, small letters denote the inputs to a transform, and the corresponding capital letters denote the corresponding

  19. Antitumour and pro-apoptotic actions of highly unsaturated fatty acids in glioma

    Microsoft Academic Search

    H. A. Leaver; H. S. Bell; M. T. Rizzo; J. W. Ironside; A. Gregor; S. B. Wharton; I. R. Whittle

    2002-01-01

    The highly unsaturated fatty acids (HUFA) of the n-6 and n-3 series are involved in cell signalling in normal and transformed cells and have recently been associated with pathways leading to tumour cell death. The antitumour activity of three HUFA (arachidonic acid, gamma linolenic acid and eicosapentaenoic acid) were studied in glioma cells and tissue. Using five glioma models, including

  20. Recombinant microorganisms for increased production of organic acids

    SciTech Connect

    Yi, Jian; Kleff, Susanne; Guettler, Michael V

    2013-04-30

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  1. Recombinant microorganisms for increased production of organic acids

    DOEpatents

    Yi, Jian (East Lansing, MI); Kleff, Susanne (East Lansing, MI); Guettler, Michael V. (Holt, MI)

    2012-02-21

    Disclosed are recombinant microorganisms for producing organic acids. The recombinant microorganisms express a polypeptide that has the enzymatic activity of an enzyme that is utilized in the pentose phosphate cycle. The recombinant microorganism may include recombinant Actinobacillus succinogenes that has been transformed to express a Zwischenferment (Zwf) gene. The recombinant microorganisms may be useful in fermentation processes for producing organic acids such as succinic acid and lactic acid. Also disclosed are novel plasmids that are useful for transforming microorganisms to produce recombinant microorganisms that express enzymes such as Zwf.

  2. Image Denoising Using Hybrid Transforms

    Microsoft Academic Search

    Walid Amin Mahmoud; Raghad Aladdin Jassim

    2007-01-01

    In this paper a new family of transformatio n for image denoising is presented, Multiridgelet and Walidlet transforms, which have been proposed as alternatives to Discrete Wavelet and Multiwavelet transforms. Walidlet transform is an intelligent tool for solving image processing problems such as image denoising with straight edges, the general algorithm of image denoising using discrete multiwavelet transform is introduced,

  3. Model transformation in the large

    Microsoft Academic Search

    Felix Klar; Alexander Königs; Andy Schürr

    2007-01-01

    Current rule-based model transformation approaches as the Query \\/ View \\/ Transformation (QVT) standard or Triple Graph Grammars (TGGs) disregard means for structuring model transformation specifications. As a result large scale model transformation specifications are hard to understand and to maintain. Furthermore, these specifications cannot utilize reusing mechanisms which would reduce the size of the specifications and improve their readability.

  4. Building an evolution transformation library

    Microsoft Academic Search

    W. Lewis Johnson; Martin S. Feather

    1990-01-01

    We have been developing knowledge-based tools to support the evolutionary development of specifications. Evolution is accomplished by means of evolution transformations, which are meaning-changing transformations applied to formal specifications. A sizable library of evolution transformations has been developed for our specification language, Gist. This paper assesses the results of our previous work on evolution transformations. It then describes our current

  5. Plastid transformation in tomato.

    PubMed

    Ruf, Stephanie; Bock, Ralph

    2014-01-01

    Tomato (Solanum lycopersicum) is one of the most important vegetable crops and has long been an important model species in plant biology. Plastid biology in tomato is especially interesting due to the chloroplast-to-chromoplast conversion occurring during fruit ripening. Moreover, as tomato represents a major food crop with an edible fruit that can be eaten raw, the development of a plastid transformation protocol for tomato was of particular interest to plant biotechnology. Recent methodological improvements have made tomato plastid transformation more efficient and facilitated applications in metabolic engineering and molecular farming. This article describes the basic methods involved in the generation and analysis of tomato plants with transgenic chloroplast genomes and summarizes current applications of tomato plastid transformation. PMID:24599859

  6. 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

  7. Folic Acid

    MedlinePLUS Videos and Cool Tools

    ... register. I'm interested in: Pregnancy Baby growth & care Research Volunteer opportunities Advocacy in government For health ... acid During your pregnancy Your pregnant body Prenatal care Eating and nutrition Physical activity Emotional and life ...

  8. ACID RAIN

    EPA Science Inventory

    Acid precipitation has become one of the major environmental problems of this decade. It is a challenge to scientists throughout the world. Researchers from such diverse disciplines as plant pathology, soil science, bacteriology, meteorology and engineering are investigating diff...

  9. Carnosic acid.

    PubMed

    Birti?, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc

    2015-07-01

    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (?70years ago) and its identification (?50years ago), numerous articles and patents (?400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. PMID:25639596

  10. Transformation of unsymmetrical dimethylhydrazine in soils

    NASA Astrophysics Data System (ADS)

    Rodin, I. A.; Smirnov, R. S.; Smolenkov, A. D.; Krechetov, P. P.; Shpigun, O. A.

    2012-04-01

    The transformation of unsymmetrical dimethylhydrazine (UDMH, a propellant component) applied at a rate of 240 g/kg to different soils was studied. The kinetic regularities of a decrease in the UDMH concentration and the accumulation of its transformation products leached out from dry and wet soils were investigated 3, 10, 30, and 90 days after its application. As the UDMH enters the soil, it vaporizes, and the elevated moisture of the soils promotes an increase in the pollutant's concentration at the initial moment; then, the concentration differences become leveled to the end of observation. It was also shown that the higher the organic matter content in the soil, the higher the UDMH concentration. However, at the end of the observations, on the 90th day, the total UDMH concentration did not exceed 0.5% of its initial content. In order to explain the UDMH behavior in the soils, one should take into account the existence of different forms of this substance and the changes in their ratios with time. The main portion of UDMH retained by the soil in the free form is transformed during the first few days. The products of the UDMH transformation, such as 1-methyl-1,2,4-triazole, formic acid dimethylhydrazide, dimethylguanidine, and dimethylamine are formed in considerable amounts, and their concentrations should be controlled in places of UDMH spills on soils.

  11. Optical coordinate transformations.

    PubMed

    Davidson, N; Friesem, A A; Hasman, E

    1992-03-10

    A novel technique for designing holographic optical elements that can perform general types of coordinate transformation is presented. The design is based on analytic ray-tracing techniques for finding the grating vector of the element, from which the holographic grating function is obtained as a solution of a Poissonlike equation. The grating function can be formed either as a computer-generated or as a computer-originated hologram. The design and realization procedure are illustrated for a specific holographic element that performs a logarithmic coordinate transformation on two-dimensional patterns. PMID:20720723

  12. 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.

  13. Toothpicks and Transformations

    NSDL National Science Digital Library

    2012-10-01

    In this math lesson, learners explore transformations and quadratic functions through toothpick patterns. Learners examine the mathematical pattern that emerges as they build a geometric design with toothpicks. The pattern is quadratic, and the learners determine the mathematical model in several different forms. Learners investigate the recursive nature of the relationship. An explicit model for the relation is developed, and a third model is developed by examining the scatterplot and determining the equation from the transformations. Finally, the group uses graphing calculators to develop another model and to verify that all of the models--factored form, vertex form, and general form--are equivalent.

  14. Acidic precipitation

    SciTech Connect

    Martin, H.C.

    1987-01-01

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

  15. 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...

  16. Cannabinoid acids analysis.

    PubMed

    Lercker, G; Bocci, F; Frega, N; Bortolomeazzi, R

    1992-03-01

    The cannabinoid pattern of vegetable preparations from Cannabis sativa (hashish, marijuana) allows to recognize the phenotype of the plants, to be used as drug or for fiber. Cannabinoid determination by analytical point of view has represented some problems caused by the complex composition of the hexane extract. Capillary gas chromatography of the hexane extracts of vegetable samples, shows the presence of rather polar constituents that eluted, with noticeable interactions, only on polar phase. The compounds can be methylated by diazomethane and silanized (TMS) by silylating reagents. The methyl and methyl-TMS derivatives are analyzed by high resolution gas chromatography (HRGC) and by gas chromatography-mass spectrometry (GC-MS). The identification of the compounds shows their nature of cannabinoid acids, which the main by quantitative point of view results the cannabidiolic acid (CBDA). It is known that the cannabinoid acids are thermally unstable and are transformed in the corresponding cannabinoids by decarboxilation. This is of interest in forensic analysis with the aim to establish the total amount of THC in the Cannabis preparations, as the active component. PMID:1503600

  17. 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

  18. Formation of urso- and ursodeoxy-cholic acids from primary bile acids by a Clostridium limosum soil isolate.

    PubMed

    Sutherland, J D; Holdeman, L V; Williams, C N; Macdonald, I A

    1984-10-01

    A gram-positive, rod-shaped anaerobe (isolate F-14) was isolated from soil. This organism was identified by cellular morphology as well as by fermentative and biochemical data as Clostridium limosum. Isolate F-14 formed ursocholic acid (UC) and 7-ketodeoxycholic acid (7-KDC) from cholic acid (CA), and ursodeoxycholic acid (UDC) and 7-ketolithocholic acid (7-KLC) from chenodeoxycholic acid (CDC) in whole cell cultures, but did not transform deoxycholic acid (DC). No hydrolysis or transformation occurred when either taurine- or glycine-conjugated bile acids were incubated with F-14. The type stain of Clostridium limosum (American Type Culture Collection 25620) did not transform bile acids. The structures of ursocholic, ursodeoxycholic, 7-ketodeoxycholic, and 7-ketolithocholic acids were verified by mass spectroscopy and by thin-layer chromatography using Komarowsky's spray reagent. The organism transformed cholic and chenodeoxycholic acids at concentrations of 20 mM and 1 mM, respectively; higher concentrations of bile acids inhibited growth. Optimal yields of ursocholic and ursodeoxycholic acids were obtained at 9-24 hr of incubation and depended upon the substrate used. Increasing yields of 7-ketodeoxycholic and 7-ketolithocholic acids, and decreasing yields of ursocholic and ursodeoxycholic acids were observed with longer periods of incubation. Culture pH changed with time and was characterized by a small initial drop (0.2-0.4 pH units) and a subsequent increase to a pH (8.1-8.2) that was above the starting pH (7.4).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6512414

  19. Transformation of the Plant Growth Regulator Daminozide (Alar) and

    E-print Network

    Huang, Ching-Hua

    Transformation of the Plant Growth Regulator Daminozide (Alar) and Structurally Related Compounds,N- Dimethylsuccinamic acid (SA), in contrast, breaks down via a hydrolytic mechanism. Introduction The plant growth heavily used plant growth regulators in the U.S. (5). In addition to daminozide, the hydrazide moiety

  20. 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...

  1. Materials and methods for efficient lactic acid production

    DOEpatents

    Zhou, Shengde; Ingram, Lonnie O'Neal; Shanmugam, Keelnatham T; Yomano, Lorraine; Grabar, Tammy B; Moore, Jonathan C

    2013-04-23

    The present invention provides derivatives of Escherichia coli constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  2. Materials and methods for efficient lactic acid production

    DOEpatents

    Zhou, Shengde (Sycamore, IL); Ingram, Lonnie O'Neal (Gainesville, FL); Shanmugam, Keelnatham T. (Gainesville, FL); Yomano, Lorraine (Gainesville, FL); Grabar, Tammy B. (Gainesville, FL); Moore, Jonathan C. (Gainesville, FL)

    2009-12-08

    The present invention provides derivatives of ethanologenic Escherichia coli K011 constructed for the production of lactic acid. The transformed E. coli of the invention are prepared by deleting the genes that encode competing pathways followed by a growth-based selection for mutants with improved performance. These transformed E. coli are useful for providing an increased supply of lactic acid for use in food and industrial applications.

  3. Acid rain report focuses on forests

    NASA Astrophysics Data System (ADS)

    Recent research on acid precipitation yields “increasing general concern about possible effects on forests,” according to the second annual report of the National Acid Precipitation Assessment Program (NAPAP). Prepared by the Interagency Task Force on Acid Precipitation, the report outlines the accomplishments of the national program during fiscal 1983, summarizes the current state of scientific knowledge (including a change in the baseline acidity of precipitation), and describes the outlook for current progress by federally funded acid precipitation research. Chris Bernabo is the program's executive director.NAPAP's annual report agrees with the finding of a National Research Council (NRC) committee that a linear relationship exists between sulfur dioxide emissions and wet deposition of sulfate (Eos, July 26, 1983, p. 475). NRC's Committee on Atmospheric Transport and Chemical Transformation in Acid Precipitation, which issued its report last year, was chaired by Jack G. Calvert of the National Center for Atmospheric Research.

  4. Omega3 Fatty Acids and Cancer

    Microsoft Academic Search

    Artemis P. Simopoulos

    2003-01-01

    Epidemiological studies and animal experiments indicate that omega-3 fatty acids exert protective effects against some common cancers, especially cancers of the breast, colon and prostate. Many mechanisms are involved, including suppression of neoplastic transformation, cell growth inhibition, and enhanced apoptosis and antiangiogenicity, through the inhibition of eicosanoid production from omega-6 fatty acids; suppression of cycloöxygenase-2 (COX-2), and interleukin-1 (IL-1) and

  5. Pulse transformer characterization

    Microsoft Academic Search

    W. H. P. Mosterdijk

    1992-01-01

    The pulse transformer at TNO PML-Pulse Physics, Delft, is characterized. It constitutes the final step of an energy compression system (Kapitza facility) which can amplify the current up to 24 times, and consists of a primary single layer winding of 24 turns enclosed in a secondary winding. There is a sine wave current source with adjustable frequencies for the characterization.

  6. Probabilistically Accurate Program Transformations

    E-print Network

    Rinard, Martin

    of loop perforation (which transforms loops to execute fewer iterations) to a set of computational the probabilistic guarantees for those bounds. 1.1 Loop Perforation In this paper, we focus on loop perforation demonstrate the util- ity and effectiveness of loop perforation in reducing the amount of time (and/or other

  7. 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…

  8. Case Study: Ecosystem Transformations

    E-print Network

    Nippert, Jesse

    142 Chapter 15 Case Study: Ecosystem Transformations Along The Colorado Front Range: Prairie Dog-tailed prairie dog. Directional changes in climate and atmospheric chemistry are altering the environment foothills and mixed-grass to short-grass prairie. Among these direc- tional changes are elevated average

  9. Fourier transform digital holography

    Microsoft Academic Search

    Dan Apostol; Adrian Sima; Petre C. Logofatu; Florin Garoi; Victor Damian; Victor Nascov; Iuliana Iordache

    2007-01-01

    In this paper a Fourier transform digital holography experimental arrangement is presented. It is actually a hybrid arrangement, half digital half analog. The Fourier hologram was constructed using the analogous means of the so called lensless configuration. The hologram was recorded digitally by a camera with a large CCD array in stead of the recording medium. The recording of the

  10. Migration by Fourier transform

    Microsoft Academic Search

    R. H. Stolt

    1978-01-01

    Wave equation migration is known to be simpler in principle when the horizontal coordinate or coordinates are replaced by their Fourier conjugates. Two practical migration schemes utilizing this concept are developed. One scheme extends the Claerbout finite difference method, greatly reducing dispersion problems usually associated with this method at higher dips and frequencies. The second scheme effects a Fourier transform

  11. Reciprocating Transformational Leadership

    Microsoft Academic Search

    Mark L. McCaslin

    1996-01-01

    Reciprocating transformational leadership has its roots in the human concept of community. Leaders, leadership, relationships, and citizenship represent observable activities within the community. They manifest themselves in the form of product, process, possibilities, and participation. Each alone can lead to a form of community improvement, however if they can be unified through a commonality of purpose extraordinary events emerge. Reciprocating

  12. Transformations: Translation (NLVM)

    NSDL National Science Digital Library

    2011-01-01

    This Java applet enables learners to explore the translation transformation (sliding) both informally and within a coordinate system. Students select and compose shapes and manipulate the ends of a translation vector to see the effect on a translated image. Links to instructions, activities and teacher/parent information are included.

  13. Transformations: Rotation (NLVM)

    NSDL National Science Digital Library

    2011-01-01

    This Java applet enables learners to explore the rotation transformation both informally and within a coordinate system. Students select and compose shapes and manipulate the center and angle of rotation to see the effect on a rotated image. Links to instructions, activities and teacher/parent information are included.

  14. Transformations: Reflection (NLVM)

    NSDL National Science Digital Library

    2011-01-01

    This Java applet enables learners to explore the reflection transformation both informally and within a coordinate system. Students select and compose shapes and manipulate the axis of symmetry (the mirror) to see the effect on a reflected image. Links to instructions, activities and teacher/parent information are included.

  15. 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…

  16. Rainbow Fourier transform

    NASA Astrophysics Data System (ADS)

    Alexandrov, Mikhail D.; Cairns, Brian; Mishchenko, Michael I.

    2012-12-01

    We present a novel technique for remote sensing of cloud droplet size distributions. Polarized reflectances in the scattering angle range between 135° and 165° 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).

  17. 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).

  18. Transformation of bromide in thermo activated persulfate oxidation processes.

    PubMed

    Lu, Junhe; Wu, Jinwei; Ji, Yuefei; Kong, Deyang

    2015-07-01

    Sulfate radicals ( [Formula: see text] ) are applied to degrade various organic pollutants. Due to its high oxidative potential, [Formula: see text] is presumed to be able to transform bromide to reactive bromine species that can react with natural organic matter subsequently to form brominated products including brominated disinfection by-products (Br-DBPs). This research was designed to investigate the transformation of bromide in thermo activated persulfate oxidation process in the presence of humic acid (HA). Significant formation of bromoform and bromoacetic acids was verified. Their formation was attributed to the reactions of HA and reactive bromine species including Br·, [Formula: see text] HOBr(-), and free bromine resulted from the oxidation of bromide by [Formula: see text] . Yields of Br-DBPs increased monotonically at persulfate concentration of 1.0 mM and working temperature of 70 °C. However, the time-depended formation exhibited an increasing and the decreasing profile when persulfate was 5.0 mM, suggesting further degradation of organic bromine. HPLC/ICP-MS analysis demonstrated that the organic bromine was eventually transformed to bromate at this condition. Thus, a transformation scheme was proposed in which the bromine could be recycled multiple times between inorganic bromide and organic bromine before being finally transformed to bromate. This is the first study that reveals the comprehensive transformation map of bromine in [Formula: see text] based reaction systems, which should be taken into consideration when such technologies are used to eliminate contamination in real practice. PMID:25898247

  19. Rapid screening of the fermentation profiles of wine yeasts by Fourier transform infrared spectroscopy

    Microsoft Academic Search

    Hélène H. Nieuwoudt; Isak S. Pretorius; Florian F. Bauer; Daniel G. Nel; Bernard A. Prior

    2006-01-01

    A rapid screening method for the evaluation of the major fermentation products of Saccharomyces wine yeasts was developed using Fourier transform infrared spectroscopy and principal component factor analysis. Calibration equations for the quantification of volatile acidity, glycerol, ethanol, reducing sugar and glucose concentrations in fermented Chenin blanc and synthetic musts were derived from the Fourier transform infrared spectra of small-scale

  20. Development of optical instrument transformer

    SciTech Connect

    Sawa, T.; Kurosawa, K. (Tokyo Electric Power Co., Inc. (Japan)); Kaminishi, T.; Yokota, T. (Toshiba Corp., Tokyo (JP))

    1990-04-01

    The optical instrument transformer is a current and voltage measuring system based on Faraday and Pockels effects,whose principles differ from those of conventional industrial transformers. In principle, this transformer is excellent in such aspects as control of electromagnetic induction noise, rationalization of electric insulation, and extension of dynamic ranges and frequency bands. By making use of such excellent properties, it is possible to achieve higher performance, higher compactness, and higher reliability of instrument transformers. This paper deals with the designing, assembling, and testing results of a prototype of an optical current transformer (CT) and that of a voltage dividing-type voltage transformer (PD).

  1. Riesz transform and Riesz potentials for Dunkl transform

    Microsoft Academic Search

    Sundaram Thangavelu; Yuan Xu

    2007-01-01

    Analogues of Riesz potentials and Riesz transforms are defined and studied for the Dunkl transform associated with a family of weight functions that are invariant under a reflection group. The Lp boundedness of these operators is established in certain cases.

  2. 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

  3. Acid Stomach

    NSDL National Science Digital Library

    Science Netlinks

    2003-08-07

    This Science NetLinks lesson is intended for a high-school, introductory chemistry class or health class. The lesson begins with an article on the history of the development of aspirin. Students will then complete a lab that compares the reaction of regular aspirin, buffered aspirin, and enteric aspirin in neutral, acidic, and basic solutions. They will then analyze the results of the experiment to gain insight into how this information was used by researchers to solve some of the problems associated with aspirin. To complete the lesson, students must understand acids and bases.

  4. Detection of inrush current in distribution transformer using wavelet transform

    Microsoft Academic Search

    A.-R. Sedighi; M.-R. Haghifam

    2005-01-01

    Inrush currents in transformers are non-sinusoidal, high magnitude currents generated due to flux saturation in the core during energization. For protection purpose, in this paper an efficient method for detection of inrush current in distribution transformer based on wavelet transform is presented. Using this method inrush current can be discriminated from the other switching transients such as: load switching, capacitor

  5. 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.

  6. 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

  7. Transformations of Designs

    Microsoft Academic Search

    Loe M. G. Feijs

    1989-01-01

    In this paper we present a theory of correctness-preserving transformations of designs. The paper gives an informal introduction to both the structuring concept of a design and to certain dynamic aspects of the software development process. There is a focus on combining designs, strategies for growing designs and re-adapting them to external-context modifications. Although the notion of a design is

  8. Magnetically Insulated Pulse Transformers

    Microsoft Academic Search

    M. Istenic; B. M. Novac; J. Luo; R. Kumar; I. R. Smith

    2007-01-01

    Summary form only given. This paper records the most recent developments in the research programme on the magnetic insulation of pulsed transformers that began at Loughborough University (LU) some six years ago, with the successful proof-of-concept demonstration of a small 100 kV prototype. Most recently, LU has designed and constructed two much larger-scale units for the study of alternative approaches

  9. Multimodal transformed social interaction

    Microsoft Academic Search

    Matthew Turk; Jeremy N. Bailenson; Andrew C. Beall; Jim Blascovich; Rosanna E. Guadagno

    2004-01-01

    Understanding human-human interaction is fundamental to the long-term pursuit of powerful and natural multimodal interfaces. Nonverbal communication, including body posture, gesture, facial expression, and eye gaze, is an important aspect of human-human interaction. We introduce a paradigm for studying multimodal and nonverbal communication in collaborative virtual environments (CVEs) called Transformed Social Interaction (TSI), in which a user's visual representation is

  10. 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.

  11. Compact gas insulated transformer

    NASA Astrophysics Data System (ADS)

    1984-01-01

    The development of design and manufacturing technologies is described. A transformer which is more efficient, more compact, lower in weight and audible sound, nonflammable, which does not rely upon mineral oil insulation, and which is compatible with the gas insulated electrical system of the future is designed. Design prototypes in the 50 MVA-345 kV range are to be tested. The program provides for economic, environmental, and systems application assessments of the emergent technologies.

  12. Tests for Hazard Transformation

    Microsoft Academic Search

    Weang Kee Ho; Robin Henderson; Peter M. Philipson

    2010-01-01

    The semiparametric Cox proportional hazards model is routinely adopted to model time-to-event data. Proportionality is a strong\\u000a assumption, especially when follow-up time, or study duration, is long. Zeng and Lin (J. R. Stat. Soc., Ser. B, 69:1–30, 2007) proposed a useful generalisation through a family of transformation models which allow hazard ratios to vary over time.\\u000a In this paper we

  13. Scale invariant feature transform

    Microsoft Academic Search

    T. Lindeberg

    2012-01-01

    Scale Invariant Feature Transform (SIFT) is an image descriptor for image-based matching developed by David Lowe (1999, 2004). This descriptor as well as related image descriptors are used for a large number of purposes in computer vision related to point matching between different views of a 3-D scene and view-based object recognition. The SIFT descriptor is invariant to translations, rotations

  14. Transformations and Frieze Patterns

    NSDL National Science Digital Library

    2010-12-29

    This geometry unit from Illuminations will help students learning about symmetry and rotation in figures and patterns. Using decorative figures and patterns, students will learn to recognize and classify symmetry. Students should have some basic knowledge of the fundamental transformations (translation, rotation and reflection- horizontal and vertical). The unit includes two lessons, each of which should require 1 class period to complete. The material is intended for grades 9-12.

  15. Genetic transformation of eucalyptus

    Microsoft Academic Search

    V. Girijashankar

    2011-01-01

    Eucalyptus is the second most widely planted multipurpose woody tree species in the world. It is a commercially important\\u000a hardwood tree for paper and wood industries. In the past two decades, various research groups reported different genetic transformation\\u000a protocols and attempts towards development of transgenic eucalyptus. Much of the work related to its genetic improvement through\\u000a transgenic technology has been

  16. 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,...

  17. Stearic Acid

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) is presented for the chemical, stearic acid. The profile lists the chemical's physical and harmful characteristics, exposure limits, and symptoms of major exposure, for the benefit of teachers and students, who use the chemical in the laboratory.

  18. Folic Acid

    MedlinePLUS

    ... lifelong disabilities. They may also need many surgeries. Anencephaly (an-en-SEF-uh-lee), which is when most or all of the brain does not develop. Babies with this problem die before or shortly after birth. The results of some studies suggest that folic acid might also help to prevent other types of ...

  19. Acid Rain

    NSDL National Science Digital Library

    This activity is part of Planet Diary and is an online examination into acid rain and sulfur dioxide emissions. Students research which states have succeeded in reducing sulfur dioxide emissions between 1980 and 1999, and which states emissions have increased. This activity is accompanied by a page of websites for further information.

  20. Acid Attack

    NSDL National Science Digital Library

    2014-09-18

    In this activity, students explore the effect of chemical erosion on statues and monuments. They use chalk to see what happens when limestone is placed in liquids with different pH values. They also learn several things that engineers are doing to reduce the effects of acid rain.

  1. 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.

  2. Regeneration and transformation of cassava

    Microsoft Academic Search

    C. J. J. M. Raemakers; E. Sofiari; E. Jacobsen; R. G. F. Visser

    1997-01-01

    A prerequisite for the development of a successful transformation system is the availability of efficient regeneration systems.\\u000a Up to 1995 the only available regeneration system in cassava was an organized type of somatic embryogenesis. Transformation\\u000a of these organized somatic embryogenic cultures with particle bombardment or Agrobacterium tumefaciens resulted in chimeric\\u000a transformed embryos. However, the transformed sector was lost after repeated

  3. Total Synthesis of (-)-Nodulisporic Acid D.

    PubMed

    Zou, Yike; Melvin, Jason E; Gonzales, Stephen S; Spafford, Matthew J; Smith, Amos B

    2015-06-10

    A convergent total synthesis of the architecturally complex indole diterpenoid (-)-nodulisporic acid D has been achieved. Key synthetic transformations include vicinal difunctionalization of an advanced ?,?-unsaturated aldehyde to form the E,F-trans-fused 5,6-ring system of the eastern hemisphere and a cascade cross-coupling/indolization protocol leading to the CDE multisubstituted indole core. PMID:26029849

  4. Membrane bioreactor for lactic acid production

    Microsoft Academic Search

    H. Moueddeb; J. Sanchez; C. Bardot; M. Fick

    1996-01-01

    A new type of membrane bioreactor is proposed for the transformation of lactose into lactic acid by Lactobacillus rhamnosus. The reactor is tubular and contains two coaxial porous alumina tubes. The internal one supports an alpha alumina membrane (mean pore size: 2.0 × 10?7 m) on its internal wall, the external one has the same membrane on its external face.

  5. Metabolic Engineering of Fatty Acid Biosynthesis in Plants

    Microsoft Academic Search

    Jay J. Thelen; John B. Ohlrogge

    2002-01-01

    Fatty acids are the most abundant form of reduced carbon chains available from nature and have diverse uses ranging from food to industrial feedstocks. Plants represent a significant renewable source of fatty acids because many species accumulate them in the form of triacylglycerol as major storage components in seeds. With the advent of plant transformation technology, metabolic engineering of oilseed

  6. Mycophenolic acid antagonizes the activation of cultured human mesangial cells

    Microsoft Academic Search

    Isabelle Dubus; Benoît Vendrely; Isabelle Christophe; Jean-Pierre Labouyrie; Yahsou Delmas; Jacques Bonnet; Christian Combe

    2002-01-01

    Mycophenolic acid antagonizes the activation of cultured human mesangial cells.BackgroundActivation of mesangial cells is observed in several forms of chronic renal disease, and in culture conditions upon stimulation by fetal calf serum (FCS), or agonists such as transforming growth factor beta (TGF-?). Mycophenolate mofetil (MMF), the precursor of mycophenolic acid (MPA), is currently used in organ transplantation and has been

  7. Azelaic acid.

    PubMed

    Nazzaro-Porro, M

    1987-12-01

    This review is an update on the literature accumulated over the past 10 years following the original observation that azelaic acid, a naturally occurring and nontoxic C9 dicarboxylic acid, possesses significant biologic properties and a potential as a therapeutic agent. These studies have shown that azelaic acid is a reversible inhibitor of tyrosinase and other oxidoreductases in vitro and that it inhibits mitochondrial respiration. It can also inhibit anaerobic glycolysis. Both in vitro and in vivo it has an antimicrobial effect on both aerobic and anaerobic (Propionibacterium acnes) microorganisms. In tissue culture it exerts a dose- and time-dependent cytotoxic effect on malignant melanocytes, associated with mitochondrial damage and inhibition of deoxyribonucleic acid (DNA) synthesis. Tumoral cell lines not containing tyrosinase are equally affected. Normal cells in culture exposed to the same concentrations of the diacid that are toxic for tumoral cells are in general not damaged. Radioactive azelaic acid has been shown to penetrate tumoral cells at a higher level than normal cells of the corresponding line. Topically applied (a 20% cream), it has been shown to be of therapeutic value in skin disorders of different etiologies. Its beneficial effect on various forms of acne (comedogenic, papulopustular, nodulocystic) has been clearly demonstrated. Particularly important is its action on abnormal melanocytes, which has led to the possibility of obtaining good results on melasma and highly durable therapeutic responses on lentigo maligna. It is also capable of causing regression of cutaneous malignant melanoma, but its role in melanoma therapy remains to be investigated.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2963038

  8. The transformation of disabilities organizations.

    PubMed

    Schalock, Robert L; Verdugo, Miguel-Angel

    2013-08-01

    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 thinking, learning, and acting. Specific application examples are given. PMID:23909588

  9. Generalized Transforms and Special Functions

    E-print Network

    G. Dattoli; E. Sabia

    2010-10-08

    We study the properties of different type of transforms by means of operational methods and discuss the relevant interplay with many families of special functions. We consider in particular the binomial transform and its generalizations. A general method, based on the use of the Fourier transform technique, is proposed for the study of the properties of functions of operators.

  10. 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…

  11. Lightning Protection for Distribution Transformers

    Microsoft Academic Search

    A. M. Opsahl; A. S. Brookes; R. N. Southgate

    1932-01-01

    Usual methods of connecting arresters for the protection of distribution transformers are often inadequate. In service some transformers still flash over although the arrester, in itself, is capable of protecting the transformer with a large margin of safety. Surge current flowing to ground through the ground lead of the arrester gives rise to inductive drop and resistance drop voltages. These

  12. VLA Antenna Pad Transformer Breaker

    E-print Network

    Groppi, Christopher

    NRAO VLA Antenna Pad Transformer Breaker Survey D-Array, October 2011, Bob Broilo #12;D-Array Antenna Pad Transformer Survey October 2011, Bob Broilo 2 Inspected by: Bob Broilo Inspection Date: 10-hand) feeds DE2. #12;D-Array Antenna Pad Transformer Survey October 2011, Bob Broilo 3 Inspected by: Bob

  13. VLA Antenna Pad Transformer Breaker

    E-print Network

    Groppi, Christopher

    NRAO VLA Antenna Pad Transformer Breaker Survey B-Array, November 22nd , 2013 Summary: None the breakers. #12;VLA Antenna Pad Transformer Breaker Survey B-Array, November 2013, Bob Broilo 2 Inspected by Visible Light Image Notes: #12;VLA Antenna Pad Transformer Breaker Survey B-Array, November 2013, Bob

  14. VLA Antenna Pad Transformer Breaker

    E-print Network

    Groppi, Christopher

    NRAO VLA Antenna Pad Transformer Breaker Survey D-Array, April 5th 2013 #12;VLA Antenna Pad2 Visible Light Image Notes: #12;VLA Antenna Pad Transformer Breaker Survey D-Array, April 2013, Bob Priority: N/A E06_IR000205_DE6.IS2 Visible Light Image Notes: #12;VLA Antenna Pad Transformer Breaker

  15. 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…

  16. Agrobacterial Transformation of Uninjured Plants

    Microsoft Academic Search

    M. I. Chumakov; I. V. Kurbanova; G. K. Solovova

    2002-01-01

    The capacity for agrobacterial transformation (using Agrobacterium tumefaciens strain GV3101 with the activated vir genes) was investigated in uninjured seedlings of tobacco (Nicotiana tabacum L.), rice (Oryza sativa L.), and wheat (Triticum aestivum L.) along with the effect of various factors on the frequency of tobacco seedling transformation. Transformed cells were found at the base of the rice leaf sheath

  17. Pharmacology of oleanolic acid and ursolic acid

    Microsoft Academic Search

    Jie Liu

    1995-01-01

    Oleanolic acid and ursolic acid are triterpenoid compounds that exist widely in food, medicinal herbs and other plants. This review summarizes the pharmacological studies on these two triterpenoids. Both oleanolic acid and ursolic acid are effective in protecting against chemically induced liver injury in laboratory animals. Oleanolic acid has been marketed in China as an oral drug for human liver

  18. 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.

  19. Solid-state acid-base reactions of indomethacin and flufenamic acid

    Microsoft Academic Search

    Xiaoming Chen

    2000-01-01

    The purpose of this study is to understand the mechanism of solid-state acid-base reactions and identify controlling factors for this type of reaction. The reactions between indomethacin and sodium bicarbonate, indomethacin and sodium carbonate, and flufenamic acid and magnesium oxide were investigated using X-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetry, and solid-state nuclear magnetic resonance spectrometry. Quantitative methods based

  20. 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.

  1. Wavelet transform: capabilities expanded

    NASA Astrophysics Data System (ADS)

    Pokorski, Krzysztof; Patorski, Krzysztof

    2014-07-01

    A review of our recently developed fringe pattern processing techniques utilizing two dimensional continuous wavelet transform is presented. Their development significantly broadens the range of 2D CWT capabilities. Namely they enable analysis of images containing multiple fringe sets and the carrier fringe contrast reversal. The methods are fully automatic and require no user interference. Their validity and robustness are confirmed using simulations. Furthermore, a novel Talbot interferometer setup utilizing binary amplitude checker gratings with its output fringe patterns successfully analyzed utilizing 2D CWT technique is presented.

  2. Industrial Transformation Science Plan

    NSDL National Science Digital Library

    From the International Human Dimensions Programme on Global Environmental Change, this "Industrial Transformation Science Plan" incorporates a multidisciplinary research effort which is "based on the assumption that important changes in production and consumption systems will be required in order to meet the needs and aspirations of a growing world population while using environmental resources in a sustainable manner." The plan has combined the input of experts in a wide range of social science disciplines with that of experts from both life and physical sciences.

  3. Bacterial Transformation Lab

    NSDL National Science Digital Library

    This PDF, part of the classroom activities site by Biotechnology Education and Training Sequence Investment (BETSI), introduces the concept of recombinant DNA and a process called transformation. Here, instructors will find detailed lab instructions/diagrams that trace out the introduction of a recombinant plasmid into a foreign bacteria resulting in the "change of the bacteria's genetic make-up and traits." With the end result of the lab being a product that "glow[s] bright green," this will be a fun lab for any chemistry or biochemistry classroom. The site even playfully boasts, "[that] you will all be genetics engineers" by the end of this experiment!

  4. Transforming cultural chaos.

    PubMed

    Schloeder, D

    1999-03-01

    Kotter believes that generating short-term wins is a critical component of the change and transformation process. Our short-term win-wins have allowed us to further collaborate, which consequently has given us more wins. These wins have been communicated. The communication has conveyed a sense of optimism and hope, and has empowered people to view change as a positive challenge. The challenge has become one in which all want to participate. Finally, we are at a point where the end of one way of life is truly the beginning of a new and better way of life. T.S. Eliot was right! PMID:10373978

  5. Domoic Acid

    NSDL National Science Digital Library

    INCHEM

    This highly detailed chemical information page features domoic acid, a toxin associated with Amnesic shellfish poisoning and naturally produced by the red algae Chondria armata and diatoms of the genus Pseudo-nitzschia. Created by the International Programme on Chemical Safety, this web page organizes information under the following sections: Name, Summary, Physio-Chemical Properties, Uses, Routes of Entry, Kinetics, Toxicology, Toxicological and Biomedical Investigations, Clinical Effects, Management, Illustrative Cases, Additional Information, References, and Authors.

  6. Nature and origins of acidity in bogs

    SciTech Connect

    Urban, N.R.

    1987-01-01

    To elucidate the causes of acidity in bogs, all of the processes generating and consuming acidity in a small peat bog in northern Minnesota were measured. These processes include ion exchange, plant nutrient uptake, atmospheric deposition, decomposition, organic acid production, sulfate reduction, and denitrification. Organic acid production was found to be the dominant source of acidity, responsible for the low pH of bog waters and the high acidity in the outflow. Net biological uptake (NBU) is the next largest source of acidity. Ion exchange accounts for only about 40% of the NBU-acidity. Plant uptake and ion exchange are much larger sources of acidity on an annual basis, but much of this acidity is neutralized by decomposition. Sulfate reduction and denitrification are quantitatively unimportant at this site because inputs (NO/sub 3//sup -/ and SO/sub 4/=) are low. Bog water samples and peat cores from bogs across northeastern North America were analyzed to determine if geographic trends in the rates of acidity-generating and -consuming processes exist. Rates of organic acid production varied little across the transect. Higher values of NBU-acidity were observed in maritime bogs than in midcontinental bogs. The effects of transformations of sulfur and nitrogen on the hydrogen-ion cycle were examined in detail. Nitrate appears to be taken up by bryophytes and little is lost to denitrification. Alkalinity from nitrate uptake is low. In contrast, there is a dynamic cycle of oxidation and reduction of sulfur within bogs. Inorganic forms of sulfur are not important storage pools in peat; 35% of the total sulfur input is accumulated as organic S.

  7. Transformational silicon electronics.

    PubMed

    Rojas, Jhonathan Prieto; Torres Sevilla, Galo Andres; Ghoneim, Mohamed Tarek; Inayat, Salman Bin; Ahmed, Sally M; Hussain, Aftab Mustansir; Hussain, Muhammad Mustafa

    2014-02-25

    In today's traditional electronics such as in computers or in mobile phones, billions of high-performance, ultra-low-power devices are neatly integrated in extremely compact areas on rigid and brittle but low-cost bulk monocrystalline silicon (100) wafers. Ninety percent of global electronics are made up of silicon. Therefore, we have developed a generic low-cost regenerative batch fabrication process to transform such wafers full of devices into thin (5 ?m), mechanically flexible, optically semitransparent silicon fabric with devices, then recycling the remaining wafer to generate multiple silicon fabric with chips and devices, ensuring low-cost and optimal utilization of the whole substrate. We show monocrystalline, amorphous, and polycrystalline silicon and silicon dioxide fabric, all from low-cost bulk silicon (100) wafers with the semiconductor industry's most advanced high-?/metal gate stack based high-performance, ultra-low-power capacitors, field effect transistors, energy harvesters, and storage to emphasize the effectiveness and versatility of this process to transform traditional electronics into flexible and semitransparent ones for multipurpose applications. PMID:24476361

  8. Energy: Energy Transformations

    NSDL National Science Digital Library

    National Science Teachers Association (NSTA)

    2006-11-01

    This Science Object is the second of four Science Objects in the Energy SciPack. It provides a conceptual and real-world understanding of how energy is transferred, from object to object and from one form of energy to another. Although the various forms of energy appear different, each can be measured in a closed system. This makes it possible to keep track of how much of one form of energy is converted into another form. Most of what goes on in the universe--from exploding stars and biological growth to the operation of machines and the motion of people--involves some form of energy being transformed into another form. The law of conservation of energy states that whenever the amount of energy in one place (or form) decreases, the amount of energy in other places (or forms) increases by the same amount. Learning Outcomes:? Recognize that there are ways to measure the amount of different kinds of energy that allow us to track how much of one form is changed into another.? Recognize that energy is conserved, meaning it is not "used up" and does not appear out of nowhere.? Give examples of transformation of energy, including recognizing the forms of energy involved.? Construct an argument against an example that claims to be a perpetual motion machine.

  9. Morphometric analysis of B 2 cAMP-induced reverse transformation in synchronized CHO cells

    Microsoft Academic Search

    S. Parodi; F. Beltrame; S. Lessin; C. Nicolini

    1979-01-01

    Summary  Synchronized transformed and reverse-transformed (by 10?3\\u000a M B2cAMP) CHO-K1 cells, growing adherent to plastic, are characterized by means of geometric and densitometric parameters at the\\u000a level of both the entire cell and of the nuclei at various time intervals after selective mitotic detachment. Transformed\\u000a and reverse-transformed cells triple-stained with Feulgen, Napthol Yellow S, and periodic acid-Schiff appeared very similar\\u000a in

  10. 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

  11. Hydrogenation of Glutamic Acid to Value Added Products

    SciTech Connect

    Holladay, John E.; Werpy, Todd A.

    2005-01-01

    Glutamic acid provides a platform to numerous compounds through thermochemical approaches including, hydrogentation, cyclyization, decarboxylation and deamination. Hydrogenation of amino acids also provides access into chiral compounds with high enantio-purity. In this paper the hydrogenation of glutamic acid is examined with an emphasis on controlling the selectivity of carbonyl reduction. Under neutral conditions at 70 ºC, glutaminol is produced (US 6,310,254). At elevated temperatures pyroglutaminol is produced. Using base, the pyrrolidinone ring can be opened to give 4-amino-5-ol-pentanoic acid. Under acidic conditions, normally used for amino acids, the pyrrolidinone carbonyl is activated and prolinol is formed. A mechanism for the various products is suggested. The results show that hydrogenation of glutamic acid has unique characteristics from other amino acids and that paradigms in the literature do not hold up for this transformation.

  12. //Create Transform & TransformGroup for object/room Transform3D room1T3D = new Transform3D();

    E-print Network

    Hill, Gary

    //Create Transform & TransformGroup for object/room Transform3D room1T3D = new Transform3D(); roomT3D.set(new Vector3f(fX, fY, fZ)); TransformGroup room1TG = new TransformGroup(room1T3D); //AddGroup ceilingTG //Create wall shape first ­ Box etc. //Create TransformGroup for object/wall Transform3D wallT3

  13. LU transformation invariant operators and LU transformation invariant

    E-print Network

    Xin-wei Zha; Chun-min Zhang

    2007-02-06

    We proposed a concept of LU transformation invariant operators. By using this operator, arbitrary multi-qubit states LU transformation invariant and SLOCC invariant could be easily obtained. And we find that presences two kinds of invariant operators and corresponding invariants. One kind of operators yields LU invariants and the other operators results in SLOCC invariants. For three-qubit states, all independence LU transformation invariant are obtained. Furthermore, by this system method, arbitrary multi-qubit states invariants can be given.

  14. Genetic transformation of Ascochyta rabiei using Agrobacterium-mediated transformation.

    PubMed

    White, David; Chen, Weidong

    2006-04-01

    In order to study pathogenic mechanisms of the plant pathogen Ascochyta rabiei, conditions for efficient transformation using Agrobacterium-mediated transformation were investigated. Hygromycin B resistance (hph) was superior to geneticin resistance (nptII) for selecting transformants, and the hph gene was more efficiently expressed by the Aspergillus nidulans trpC promoter than by the Cauliflower mosaic virus 35S promoter CaMV35S. Co-cultivation on solid media for 72 h was optimal for generating transformants, but increasing the ratio of bacterial cells to conidia did not affect transformation efficiency. All hygromycin B-resistant transformants carried transfer-DNA (T-DNA) as determined by polymerase chain reaction (PCR) and the T-DNA integrations appeared to be random and in single copy as detected by Southern hybridization. Transformants remained resistant to hygromycin B in the absence of selection. Variations in colony morphology were observed in the presence of hygromycin B under different culture conditions, and a variety of altered phenotypes including reduced virulence were observed among 550 transformants. Inverse PCR was more efficient than TAIL-PCR in identifying flanking genomic sequences from T-DNA borders, and the possible causes are discussed. This transformation technique and recovery of flanking DNA using inverse PCR will provide a useful tool for genetic studies of A. rabiei. PMID:16369840

  15. SHORT-TERM CHANGES IN THE BASE NEUTRALIZING CAPACITY OF AN ACID ADIRONDACK LAKE, NEW YORK

    EPA Science Inventory

    Concern and controversy over the effects of acidic deposition on low ionic strength surface wa ters has led to much discussion on the nature and extent of proton transformations within acid sensitive ecosystems. The source of base neutralizing capacity(BNC) within acid surface wa...

  16. Comparison of serum and bronchoalveolar lavage fluid sialic acid levels between malignant and benign lung diseases

    Microsoft Academic Search

    Turgut Isitmangil; Gulbu Isitmangil; Yasemin Budak; Recep Aydilek; Mehmet Kutlu Celenk

    2001-01-01

    BACKGROUND: It is known that tissue and serum sialic acid levels may be altered by malignant transformation. In this study, sialic acid levels were determined in bronchoalveolar lavage fluid (BAL) and serum in two groups of patients with lung cancer and non-malignant diseases of the lung. METHODS: Colorimetric methods were used for determination sialic acid in serum and in BAL

  17. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

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

  18. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  19. z Transform Chapter Intended Learning Outcomes

    E-print Network

    So, Hing-Cheung

    z Transform Chapter Intended Learning Outcomes: (i) Understanding the relationship between transform and the Fourier transform for discrete-time signals (ii) Understanding the characteristics and properties of transform (iii) Ability to compute transform and inverse transform (iv) Ability to apply

  20. Acid Ocean

    NSDL National Science Digital Library

    The I2I-Acid Ocean virtual lab is an e-learning activity where students become virtual scientists studying the impact of ocean acidification on sea urchin larval growth. Students recreate a real, up-to-date climate change experiment. They also learn important general scientific principles, such as the importance of sample size and numbers of replicates, and discuss what this research into a specific impact of climate change may mean for the future of our oceans. There is a French translation available.

  1. 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.

  2. Brnsted Acids The Strongest Isolable Acid**

    E-print Network

    Reed, Christopher A.

    Brønsted Acids The Strongest Isolable Acid** Mark Juhasz, Stephan Hoffmann, Evgenii Stoyanov, Kee-Chan Kim, and Christopher A. Reed* Acids based on carborane anions as conjugate bases (Figure 1) are a new class of Brønsted (protic) acids, notable for their "strong yet gentle" qualities.[1] For example

  3. 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.

  4. Discrete Pulse Transform of Images

    Microsoft Academic Search

    Roumen Anguelov; Inger Fabris-rotelli

    2008-01-01

    \\u000a The Discrete Pulse Transform (DPT) of images is defined by using a new class of LULU operators on multidimensional arrays.\\u000a This transform generalizes the DPT of sequences and replicates its essential properties, e.g. total variation preservation.\\u000a Furthermore, the discrete pulses in the transform capture the contrast in the original image on the boundary of their supports.\\u000a Since images are perceived

  5. Pulse transformer for electron gun

    Microsoft Academic Search

    P. S. Antsupov; I. M. Matora; V. A. Shvets

    1976-01-01

    A pulse transformer with an output voltage 720 kV and a current of 170 A with a pulse duration 1.4 ..mu..sec is described along with an autotransformer designed for a voltage of 640 kV. The high output voltage is attained by connecting several transformers in series and applying the voltage to the primary winding of each series transformer through a

  6. 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.

  7. Phase transformations in high polymers

    Microsoft Academic Search

    H. D. Keith

    1973-01-01

    Phase transformations in high polymers are reviewed broadly and with the purpose of high-lighting the similarities and dissimilarities\\u000a between behavior in high polymers and in metals. Emphasis is placed upon the kinetic restraints that make phase transformations\\u000a in high polymers sluggish for the most part, and upon the molecular factors that underlie them. The review deals specifically\\u000a with transformations of

  8. Transformation: emergence of the self

    E-print Network

    Stein, Murray

    1998-01-01

    CHAPTER 2 The Transformative Image 39 CHAPTER 3 Transformative Relationships 69 CHAPTER 4 Three Portraits of Transformation: Rembrandt, Picasso, Jung 106 Epilogue 143 Notes 149 Bibliography 161 Index 165 ILLUSTRATIONS The Mithraic god Aion page... 47 The Rosarium Series beginning page 87 Rembrandt, Self-Portrait, 1658 page 113 Rembrandt, Self-Portrait, c. 1661-62 115 Rembrandt, Self-Portrait, Laughing 117 Rembrandt, Self-Portrait as the Apostle Paul 119 Picasso, Self-Portrait with Palette...

  9. Lifetime management of power transformers

    Microsoft Academic Search

    C. Sumereder; M. Muhr; B. Körbler

    2003-01-01

    Power transformers belong to the most important and most cost-intensive equipment of electrical power transmission and distribution.\\u000a If an error in a transformer occurs, this causes not only an interruption of the electrical power supply of far areas but\\u000a also large economic losses beyond that. Thus, the operation of transformers must guarantee a continuous and error free power\\u000a supply over

  10. Optical transforms in digital holography

    NASA Astrophysics Data System (ADS)

    Yaroslavsky, L.

    2006-05-01

    Digital holography is a symbiosis of physical optics and digital computers. In numerical reconstruction of optical holograms, optical wavefront is sampled, and obtained numerical data are transformed in computers for evaluating physical properties of objects that produced that wave front. In fabricating computer-generated holograms, numerical data produced by a computer are converted into a physical hologram or an optical element intended for forming real optical beams. Therefore mutual correspondence between optical transformations and their computer representations is of fundamental importance for digital holography. In the paper, this problem is addressed and different computer representations of basic optical transforms such as convolution, Fourier and Fresnel integral transforms are briefly reviewed.

  11. Algorithm For Integer Cosine Transforms

    NASA Technical Reports Server (NTRS)

    Pollara, Fabrizio; Cheung, Kar-Ming; Shahshahani, Mehrdad

    1994-01-01

    Algorithm computes coefficients of integer cosine transforms, containing only integer coefficients approximately proportional to floating-point coefficients of discrete cosine transforms. Used in compression of image data in blocks of N x N pixels, discrete cosine transforms involve large amounts of computation, typically amounting to 80 percent of computational load in data-compression scheme. In constructing integer approximations, competing requirements are to obtain data-compression and data-decompression performances comparable to those of corresponding descrete cosine transforms while taking advantage of simplicity afforded by integer arithmetic to reduce complexity and amount of computation.

  12. 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

  13. 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…

  14. 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.

  15. Comparing transformation languages for the implementation of certified model transformations

    E-print Network

    Paris-Sud XI, Université de

    from low-level models. On the other hand, modeling languages have often (but not always) clearly and implementation flaws. Most com- monly the final implementation is verified against the low level requirements viaComparing transformation languages for the implementation of certified model transformations Arnaud

  16. Transformation Nets -A Runtime Model for Transformation Languages

    E-print Network

    Hochreiter, Sepp

    of Software Technology and Interactive Systems Vienna University of Technology Favoritenstraße 9 as first-class arti- facts throughout the software lifecycle requiring the availability of proper)--called Transformation Nets--for the development, execution and debugging of model transformations on a high level

  17. Transformation of synthetic pyrethroid insecticides by a thermophilic Bacillus sp

    Microsoft Academic Search

    S. E. Maloney; A. Maule; A. R. W. Smith

    1992-01-01

    Employing a mineral salts medium containing Tween 80 as the primary carbon source, a strain of Bacillus stearothermophilus was isolated which was able to hydrolyse selected second and third-generation pyrethroids to non-insecticidal products. Of a range of pyrethroid insecticides the trans-isomer of permethrin was the most readily transformed by this microbial isolate, whilst flumethrin was the least. 3-Phenoxybenzoic acid and

  18. Shoot regeneration and Agrobacterium -mediated transformation of Fragaria vesca L

    Microsoft Academic Search

    Iman Mansouri; José A. Mercado; Victoriano Valpuesta; José M. López-Aranda; Fernando Pliego-Alfaro; Miguel A. Quesada

    1996-01-01

    An efficient and reliable method for shoot regeneration from leaf disks of Fragaria vesca L. has been developed. This protocol has been successfully employed to obtain transformed plants using Agrobacterium tumefaciens as gene vector. Murashige and Skoog basal medium supplemented with benzyladenine (4 mg\\/l) and indole-3-butyric acid (0.25 mg\\/l) induced the maximum percentage of shoot regeneration (98%) and the highest

  19. The determination of peroxide value by fourier transform infrared spectroscopy

    Microsoft Academic Search

    F. R. van de Voort; A. A. Ismail; J. Sedman; J. Dubois; T. Nicodemo

    1994-01-01

    A rapid method for the quantitative determination of peroxide value (PV) of vegetable oils by Fourier transform infrared (FTIR)\\u000a transmission spectroscopy is described. Calibration standards were prepared by the addition oft-butyl hydroperoxide to a series of vegetable oils, along with random amounts of oleic acid and water. Additional standards\\u000a were derived through the addition of mono- and diglyceride spectral contributions,

  20. Selective matrix acidizing of horizontal wells

    SciTech Connect

    Motta, E.P. da [Petrobras R and D Center, Rio de Janeiro (Brazil); Hill, A.D.; Sepehrnoori, K. [Univ. of Texas, Austin, TX (United States)

    1995-08-01

    The PI of a horizontal well in an anisotropic medium is calculated during a process of partial acidization, in which damage removal occurs over only a fraction of the well length. Two numerical simulators are used in this work: an acidizing simulator, which calculates the permeability distribution around the wellbore; and a reservoir simulator, which calculates the PI of the well. By applying mathematical transformations, it is possible to reduce the acidizing model from a 2D to a 1D problem. By comparing treatment results, it is possible to select the optimal volume of acid, injection rate, and fraction of the length to be acidized for each well. The same procedure also may be applied for vertical wells both with and without anisotropy. Simulation results indicate that the application of a partial acidizing strategy reduces the total amount of acid required for significant improvement in well productivity, substantially reducing the financial, operational, and environmental risks involved in the treatment of a horizontal well. In most cases, the optimal injection rate for sandstone acidizing is the maximum rate that does not fracture the formation.

  1. Stable chloroplast transformation of the unicellular red alga Porphyridium species.

    PubMed

    Lapidot, Miri; Raveh, Dina; Sivan, Alex; Arad, Shoshana Malis; Shapira, Michal

    2002-05-01

    Red algae are extremely attractive for biotechnology because they synthesize accessory photosynthetic pigments (phycobilins and carotenoids), unsaturated fatty acids, and unique cell wall sulfated polysaccharides. We report a high-efficiency chloroplast transformation system for the unicellular red microalga Porphyridium sp. This is the first genetic transformation system for Rhodophytes and is based on use of a mutant form of the gene encoding acetohydroxyacid synthase [AHAS(W492S)] as a dominant selectable marker. AHAS is the target enzyme of the herbicide sulfometuron methyl, which effectively inhibits growth of bacteria, fungi, plants, and algae. Biolistic transformation of synchronized Porphyridium sp. cells with the mutant AHAS(W492S) gene that confers herbicide resistance gave a high frequency of sulfomethuron methyl-resistant colonies. The mutant AHAS gene integrated into the chloroplast genome by homologous recombination. This system paves the way for expression of foreign genes in red algae and has important biotechnological implications. PMID:12011332

  2. Acid rain

    SciTech Connect

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

    1983-01-01

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

  3. Apparatus and method for transforming living cells

    DOEpatents

    Okandan, Murat; Galambos, Paul C.

    2003-11-11

    An apparatus and method are disclosed for in vitro transformation of living cells. The apparatus, which is formed as a microelectromechanical device by surface micromachining, can be used to temporarily disrupt the cell walls or membrane of host cells one at a time so that a particular substance (e.g. a molecular tag, nucleic acid, bacteria, virus etc.) can be introduced into the cell. Disruption of the integrity of the host cells (i.e. poration) can be performed mechanically or electrically, or by both while the host cells are contained within a flow channel. Mechanical poration is possible using a moveable member which has a pointed or serrated edge and which is driven by an electrostatic actuator to abrade, impact or penetrate the host cell. Electroporation is produced by generating a relatively high electric field across the host cell when the host cell is located in the flow channel between a pair of electrodes having a voltage applied therebetween.

  4. Transformation of cinoxacin by Beauveria bassiana.

    PubMed

    Parshikov, Igor A; Moody, Joanna D; Heinze, Thomas M; Freeman, James P; Williams, Anna J; Sutherland, John B

    2002-08-27

    The ability of the fungus Beauveria bassiana ATCC 7159 to transform the antibacterial agent cinoxacin was investigated. Cultures in sucrose-peptone broth were dosed with cinoxacin, grown for 20 days, and then extracted with ethyl acetate. Two metabolites were detected and purified by high-performance liquid chromatography. The major metabolite was identified by mass and proton nuclear magnetic resonance spectra as 1-ethyl-1,4-dihydro-3-(hydroxymethyl)[1,3]dioxolo[4,5-g]cinnolin-4-one and the minor metabolite was identified as 1-ethyl-1,4-dihydro-6,7-dihydroxy-3-(hydroxymethyl)cinnolin-4-one. B. bassiana also reduced quinoline-3-carboxylic acid to 3-(hydroxymethyl)quinoline. PMID:12204384

  5. Effects of natural organic matter model compounds on the transformation of carbon tetrachloride by chloride green rust.

    PubMed

    Liang, Xiaoming; Butler, Elizabeth C

    2010-04-01

    Interest has grown in the use of reactive minerals for natural and engineered transformation of ground water contaminants. This study investigated how the structural properties of 10 model compounds representing natural organic matter (NOM) influenced their adsorption to chloride green rust (GR-Cl), and how this adsorption affected rate constants for transformation of carbon tetrachloride (CT) by GR-Cl. The affinity of benzoic acid, phthalic acid, trimesic acid, pyromellitic acid, and mellitic acid for the GR-Cl surface generally increased in the order of increasing number of carboxylic acid functional groups, increasing acidity of these functional groups, and increasing charge density. For NOM model compounds that had phenolic functional groups (p-hydroxybenzoic acid, alpha-resorcylic acid, and caffeic acid), the affinity for the GR-Cl surface was greatest for caffeic acid, which had two adjacent phenolic functional groups. Some NOM model compounds had experimentally determined Langmuir maximum adsorption capacities (q(max-Langmuir)) greater than those calculated based on external surface area measurements and the size of the NOM model compound, suggesting adsorption to internal as well as external sites at the GR-Cl surface for these compounds. Rate constants for CT transformation by GR-Cl generally decreased as the affinity of the NOM model compounds (estimated by Langmuir K values) increased, but there was no statistically significant correlation between Langmuir parameters (i.e., K and q(max-Langmuir)) and rate constants, perhaps due to significant adsorption of some NOM model compounds to sites that were not accessible to CT, such as interlayer sites. Unlike the other NOM model compounds, caffeic acid, which adsorbed to a significant extent to the GR-Cl surface, increased the rate constant for CT transformation. The influence of NOM on rate constants for CT transformation by green rusts should be considered in ground water remediation planning. PMID:20045548

  6. Transformational Design of Digital Circuits

    Microsoft Academic Search

    P. F. A. Middelhoek

    1993-01-01

    A new design method for synchronous digital VLSI circuits based on the ideas of transformational design is developed. The central idea is to derive an implementation from a behavioral specification by means of behavior-preserving transformations. An essential part of such a methodology is a design representation language which can be used during the complete synthesis trajectory. For this purpose a

  7. 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…

  8. Coordinate Transformations in Object Recognition

    Microsoft Academic Search

    Markus Graf

    2006-01-01

    A basic problem of visual perception is how human beings recognize objects after spatial transformations. Three central classes of findings have to be accounted for: (a) Recognition performance varies systematically with orientation, size, and position; (b) recognition latencies are sequentially additive, suggesting analogue transformation processes; and (c) orientation and size congruency effects indicate that recognition involves the adjustment of a

  9. Simplified Relativistic Force Transformation Equation.

    ERIC Educational Resources Information Center

    Stewart, Benjamin U.

    1979-01-01

    A simplified relativistic force transformation equation is derived and then used to obtain the equation for the electromagnetic forces on a charged particle, calculate the electromagnetic fields due to a point charge with constant velocity, transform electromagnetic fields in general, derive the Biot-Savart law, and relate it to Coulomb's law.…

  10. Travel and Adult Transformative Learning

    ERIC Educational Resources Information Center

    Lindstrom, Steven K.

    2011-01-01

    This phenomenological research study examines the lived experience of individual adult transformation in the context of travel. Adults throughout history have experienced profound personal and perception changes as a result of significant travel events. Transformative learning occurs through experience, crisis, and reflection, all of which are…

  11. Coordinate Transformations in Object Recognition

    ERIC Educational Resources Information Center

    Graf, Markus

    2006-01-01

    A basic problem of visual perception is how human beings recognize objects after spatial transformations. Three central classes of findings have to be accounted for: (a) Recognition performance varies systematically with orientation, size, and position; (b) recognition latencies are sequentially additive, suggesting analogue transformation…

  12. Electromagnetic Design With Transformation Optics

    Microsoft Academic Search

    Nathan B. Kundtz; David R. Smith; John B. Pendry

    2011-01-01

    Transformation optics is an emerging technique for the design of advanced electromagnetic media. Transfor- mation optical devices exploit the form invariance of Maxwell's equations, allowing geometry to play the dominant role in the design process rather than traditional wave or ray optics. The use of coordinate transformations vastly eases the burden of design for a large class of devices, though

  13. 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…

  14. Time Temperature Transformation (TTT) Diagrams

    E-print Network

    Cambridge, University of

    isothermal transformation diagram Definition: TTT diagrams give the kinetics of isothermal transformations. 2 measurement, dilatometry (Fig. 3), electrical resistivity method, magnetic permeability, in situ diffraction-temperature salt-bath for isothermal treatment. Fig. 1 : Salt bath I -austenitisation heat treatment. 4 #12;Fig . 3

  15. Transformation of Wave Height Distribution

    Microsoft Academic Search

    Edward B. Thornton; R. T. Guza

    1983-01-01

    Earlier models of random wave transformation are reviewed in the first section. Then the transformation of waves, including dissipation due to breaking and bottom friction, is described by an energy flux balance model. The wave height pdf of all waves (broken and unbroken) is shown by the field data to be well described by the Rayleigh distribution everywhere. The observed

  16. Globalization, Labor, Transformation of Work

    E-print Network

    Globalization, Labor, and the Transformation of Work Readings for Seeking a Competitive Advantage in an Increasingly Global Economy Edited by Jonathan H. Westover THE ORGANISATION #12;First published in Australia-in-Publication data: Globalization, labor & the transformation of work: readings for seeking a competitive advantage

  17. Transformation of the Independent Variables

    Microsoft Academic Search

    G. E. P. Box; Paul W. Tidwell

    1962-01-01

    In representing a realationship between a response and a number of independent variables, it is preferable when possible to work with a simple functional form in transformed variables rather than with a more complicated form in the original variables. This paper describes and illustrates a procedure to estimate appropriate transformations in this context.

  18. Conformal Transformations and Space Travel

    Microsoft Academic Search

    Suraj N. Gupta

    1961-01-01

    Conformal transformations are applied to the motion of a space ship experiencing a constant acceleration. The role of proper time is interpreted in terms of atomic periods, and the relationship between the conformal transformations and the general theory of relativity is clarified.

  19. Database Transformations for Biological Applications

    SciTech Connect

    Overton, C.; Davidson, S. B.; Buneman, P.; Tannen, V.

    2001-04-11

    The goal of this project was to develop tools to facilitate data transformations between heterogeneous data sources found throughout biomedical applications. Such transformations are necessary when sharing data between different groups working on related problems as well as when querying data spread over different databases, files and software analysis packages.

  20. Transformational Leadership: Democratic or Despotic?

    ERIC Educational Resources Information Center

    Allix, Nicholas M.

    2000-01-01

    James MacGregor Burns's conceptualization of transforming leadership stressed the moral and educative nature of the leader-follower relationship. However, critical examination of Burns's account uncovers philosophical and technical difficulties with some of his central claims. Transformative leadership may be structured more for domination than…

  1. POWER TRANSFORMER INCIPIENT FAULTS MONITORING

    Microsoft Academic Search

    Cristina CIULAVU; Elena HELEREA

    2008-01-01

    Power transformers are important and expensive components in the electric power system. The knowledge of the actual status of the transformer insulation behavior, load tap changer performance, temperature, and load condition is necessary in order to evaluate the service performance concerning reliability, availability and safety. Systems abnormalities, loading, switching and ambient condition normally contribute towards accelerated aging and sudden failure.

  2. Estimate transformer-failure cost

    Microsoft Academic Search

    1978-01-01

    Power transformers of major manufacturers differ significantly in their failure rate; no manufacturer builds units that are consistently more reliable than those of other manufacturers for all voltage ranges. But utilities can take these differences into economic consideration by assigning to each unit the expected cost of failure. When this figure is added to the initial cost of a transformer,

  3. Lightning Protection for Distribution Transformers

    Microsoft Academic Search

    T. H. Haines; C. A. Corney

    1932-01-01

    This paper presents a five year history of the results of lightning arrester protection for distribution transformers in New England where the normal ground electrode resistance is much higher than in most other parts of this country. The experience shows that the trouble rate of the protected transformers has consistently been materially less than that of those not protected, notwithstanding

  4. VLA Antenna Pad Transformer Breaker

    E-print Network

    Groppi, Christopher

    NRAO VLA Antenna Pad Transformer Breaker Survey A-Array, May 20, 2014 Summary: The breakers at AN5 and AN6 show clear signs of degradation since 2011 and should be replaced. #12;VLA Antenna Pad Notes: #12;VLA Antenna Pad Transformer Breaker Survey A-Array, May 2014, Bob Broilo 3 Inspected by: Bob

  5. VLA Antenna Pad Transformer Breaker

    E-print Network

    Groppi, Christopher

    NRAO VLA Antenna Pad Transformer Breaker Survey C-Array, August 20th 2013 #12;VLA Antenna Pad. Antenna is scheduled to move off this pad soon, so replacement can probably wait until next D-array when: #12;VLA Antenna Pad Transformer Breaker Survey C-Array, August 2013, Bob Broilo 3 Inspected by: Bob

  6. Multiple fractional Fourier transform holography

    NASA Astrophysics Data System (ADS)

    Zeng, Yangsu; Zhang, Yixiao; Gao, Feng; Gao, Fuhua; Huang, Xiaoyang; Guo, Yongkang

    2002-04-01

    In this paper, we introduce the recording and reconstruction theories of the multiple fractional Fourier transform hologram (M-FRTH). We fabricated a multiple fractional Fourier transform hologram, and obtained satisfying reconstruction results. The experimental result shows that the M-FRTH has a high anti-counterfeiting capacity and can be used in the fabrication of the trademark, ID, and the notes.

  7. Formation of urso- and ursodeoxy-cholic acids from primary bile acids by Clostridium absonum.

    PubMed

    Macdonald, I A; Hutchison, D M; Forrest, T P

    1981-03-01

    Eight strains of Clostridium absonum were shown to form ursocholic acid (UC) from cholic acid (C) and ursodeoxycholic acid (UDC) from chenodeoxycholic acid (CDC) but did not transform deoxycholic acid (DC) in whole cell cultures. The structures of UC and UDC were verified by mass spectroscopy, and by thin-layer chromatography using Komarowsky's spray reagent. The organism transformed C and CDC at concentrations below 1.5. 10(-3) M and 5.0. 10(-4) M, respectively; higher concentrations were inhibitory. Optimal yields of the final products were realized at about 15-22 hr and 9-15 hr of incubation, respectively, and were in the range of 60-70%. Additionally, the 7 keto-derivatives, 7 keto-deoxycholic acid (7K-DC) or 7 keto-lithocholic acid (7K-LC) were also formed from C and CDC. With longer periods of incubation, increasing yields of 7K-DC and 7K-LC and decreasing yields of UC and UDC were observed. These time course studies suggest that 7K-DC and 7K-LC are intermediates in the formation of UC and UDC from the primary bile acids. We propose the occurrence of C right harpoon over left harpoon 7K-DC right harpoon over left harpoon UC and CDC right harpoon over left harpoon 7K-LC right harpoon over left harpoon UDC with increasing dominance of back reaction of the second step on aging of the culture. When the initial pH value of the medium was manipulated within the range of 5.8-9.0, increasing yields of UDC from CDC were obtained at higher pH values (maximum yield at pH 9.0 was 83%), with total inhibition of growth and transformation at pH 5.8. In contrast, UC was produced from C at all pH values studied, with marginal differences in yields (maximum yield at pH 8.0 was 50%). In all cases, formation of UC from C was much slower than that of UDC from CDC. In contrast, C. paraperfringens transformed none of the above bile acids. We propose that C. absonum, or a biochemically similar species, may be present in the human gut and give rise to UDC (and UC) in vivo.-Macdonald, I. A., D. M. Hutchison, and T. P. Forrest. Formation of urso- and ursodeoxycholic acids from primary acids by Clostridium absonum. PMID:6940948

  8. The use of Agrobacterium rhizogenes transformed roots to obtain transgenic shoots of the apple rootstock Jork 9

    Microsoft Academic Search

    Nathalie Pawlicki-Jullian; Monika Sedira; Margareta Welander

    2002-01-01

    The apple rootstock Jork 9 was transformed using four different Agrobacterium rhizogenes virulent strains. The mannopine strain 8196 gave the best results in the production of chimeric plants compared to two agropine strains (A4 and 15834) and one cucumopine strain. Shoot regeneration was performed on both untransformed and transformed roots. Optimum combination and concentration of thidiazuron (TDZ) and a-naphtaleneacetic acid

  9. Catalytic, Enantioselective [4 + 2]-Cycloadditions of Ketene Enolates and o-Quinones: Efficient Entry to Chiral, r-Oxygenated Carboxylic Acid

    E-print Network

    Lectka, Thomas

    available acid chlorides and a cinchona alkaloid-based catalyst. Additionally, the chiral cycloadducts can the standard transformation of an acid chloride into a chiral ketene enolate (10 mol % of a cinchona alkaloid

  10. Multiple Domains of the Jaagsiekte Sheep Retrovirus Envelope Protein Are Required for Transformation of Rodent Fibroblasts

    PubMed Central

    Hofacre, Andrew; Fan, Hung

    2004-01-01

    Jaagsiekte sheep retrovirus (JSRV) is an exogenous retrovirus of sheep that induces a contagious lung cancer, ovine pulmonary adenocarcinoma. We previously showed that the gene encoding JSRV envelope protein (Env) appears to function as an oncogene, since it can transform mouse NIH 3T3 cells. The cytoplasmic tail of the Env transmembrane protein (TM) is necessary for the transformation. However, previous experiments did not exclude the involvement of the Env surface protein (SU) in transformation. In this study, we created a series of nested deletion mutants through the SU domain and assessed their ability to transform rodent fibroblasts. All SU deletion mutants downstream of the predicted signal peptide were unable to transform murine NIH 3T3 or rat 208F cells. Transport to the plasma membrane of selected deleted Env proteins was confirmed by confocal immunofluorescence microscopy of hemagglutinin-tagged versions. Additional sequential SU deletion mutants lacking 50-amino-acid (aa) blocks throughout SU also were unable to transform. Furthermore, minimal insertion mutants of two amino acids (Leu/Gln) at various positions in SU also abolished transformation. These data indicate that domains in SU facilitate efficient JSRV transformation. This could reflect a necessity of SU for appropriate configuration of the Env protein or independent activation by SU of a signaling pathway necessary for transformation. Complementation between SU and TM mutants for transformation supported the latter hypothesis. Cotransfection with ?GP Y590F (mutant in the TM cytoplasmic tail) with ?GP SU?103-352 (lacking most of SU) resulted in efficient transformation. The resulting transformants showed evidence for the presence and expression of both mutant plasmids. PMID:15367614

  11. Identification of diamino acids in the Murchison meteorite

    NASA Astrophysics Data System (ADS)

    Meierhenrich, Uwe J.; Muñoz Caro, Guillermo M.; Hendrik Bredehöft, Jan; Jessberger, Elmar K.; Thiemann, Wolfram H.-P.

    Amino acids identified in the Murchison chondritic meteorite by molecular and isotopic analysis are thought to have been delivered to the early Earth by asteroids, comets, and interplanetary dust particles where they may have triggered the appearance of life by assisting in the synthesis of proteins via prebiotic polycondensation reactions [Oró, J. (1961) Nature 190, 389-390; Chyba, C. F. & Sagan, C. (1992) Nature 355, 125-132]. We report the identification of diamino acids in the Murchison meteorite by new enantioselective GC-MS analyses. DL-2,3-diaminopropanoic acid, DL-2,4-diaminobutanoic acid, 4,4'-diaminoisopentanoic acid, 3,3'-diaminoisobutanoic acid, and 2,3-diaminobutanoic acid were detected in the parts per billion range after chemical transformation into N,N-diethoxycarbonyl ethyl ester derivatives. The chiral diamino acids show a racemic ratio. Laboratory data indicate that diamino acids support the formation of polypeptide structures under primitive Earth conditions [Brack, A. & Orgel, L. E. (1975) Nature 256, 383-387] and suggest polycondensation reactions of diamino acids into early peptide nucleic acid material as one feasible pathway for the prebiotic evolution of DNA and RNA genomes [Joyce, G. F. (2002) Nature 418, 214-221]. The results obtained in this study favor the assumption that not only amino acids (as the required monomers of proteins) form in interstellar/circumstellar environments, but also the family of diamino monocarboxylic acids, which might have been relevant in prebiotic chemistry.

  12. The Hyperanalytic Wavelet Transform

    E-print Network

    S. C. Olhede; G. Metikas

    2006-05-23

    In this paper novel classes of 2-D vector-valued spatial domain wavelets are defined, and their properties given. The wavelets are 2-D generalizations of 1-D analytic wavelets, developed from the Generalized Cauchy-Riemann equations and represented as quaternionic functions. Higher dimensionality complicates the issue of analyticity, more than one `analytic' extension of a real function is possible, and an `analytic' analysis wavelet will not necessarily construct `analytic' decomposition coefficients. The decomposition of locally unidirectional and/or separable variation is investigated in detail, and two distinct families of hyperanalytic wavelet coefficients are introduced, the monogenic and the hypercomplex wavelet coefficients. The recasting of the analysis in a different frame of reference and its effect on the constructed coefficients is investigated, important issues for sampled transform coefficients. The magnitudes of the coefficients are shown to exhibit stability with respect to shifts in phase. Hyperanalytic 2-D wavelet coefficients enable the retrieval of a phase-and-magnitude description of an image in phase space, similarly to the description of a 1-D signal with the use of 1-D analytic wavelets, especially appropriate for oscillatory signals. Existing 2-D directional wavelet decompositions are related to the newly developed framework, and new classes of mother wavelets are introduced.

  13. 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

  14. Parallel fast gauss transform

    SciTech Connect

    Sampath, Rahul S [ORNL; Sundar, Hari [Siemens Corporate Research; Veerapaneni, Shravan [New York University

    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.

  15. Chirped-pulsed FTMW spectra of valeric acid, 5-aminovaleric acid, and ?-valerolactam: A study of amino acid mimics in the gas phase

    NASA Astrophysics Data System (ADS)

    Bird, Ryan G.; Vaquero-Vara, Vanesa; Zaleski, Daniel P.; Pate, Brooks H.; Pratt, David W.

    2012-10-01

    The lowest energy conformations of valeric acid (VA) and ?-valerolactam (DVL) were determined using chirped-pulsed Fourier transform microwave spectroscopy. DVL was produced by heating 5-aminovaleric acid (AVA) in a metal nozzle. A study of the reaction pathway leading to DVL identified the preferred structure of AVA and demonstrated that an n ? ?* interaction plays the key role in the transformation of reactant into product. An inverse kinetic isotope effect was detected for this process. Additionally, the spectra of single and double water complexes of DVL along with the 13C and 15N-substituted species (in natural abundance) were collected and analyzed.

  16. ISOLATION OF THE FIRST PISCINE TRANSFORMING GROWTH FACTOR ? GENE: ANALYSIS REVEALS TISSUE SPECIFIC EXPRESSION AND A POTENTIAL REGULATORY SEQUENCE IN RAINBOW TROUT ( ONCORHYNCHUS MYKISS )

    Microsoft Academic Search

    Laura J. Hardie; Kerry J. Laing; Garry D. Daniels; Peter S. Grabowski; Charles Cunningham; Christopher J. Secombes

    1998-01-01

    The nucleotide sequence of the rainbow trout transforming growth factor ? (TGF-?) peptide is presented, which translates into a 382 amino acid precursor molecule containing a 20 amino acid leader and a mature peptide of 112 amino acids. The mature peptide has nine conserved cysteines and a conserved proline (position 36) and glycine (position 46), all characteristic of TGF-? superfamily

  17. Pivalic acid acts as a starter unit in a fatty acid and antibiotic biosynthetic pathway in Alicyclobacillus, Rhodococcus and Streptomyces.

    PubMed

    Rezanka, Tomáš; Siristova, Lucie; Schreiberová, Olga; Rezanka, Michal; Masák, Jan; Melzoch, Karel; Sigler, Karel

    2011-06-01

    A biosynthetic pathway using pivalic acid as a starter unit was found in three bacterial species, Alicyclobacillus acidoterrestris, Rhodococcus erythropolis and Streptomyces avermitilis. When deuterium-labelled pivalic acid was added to A. acidoterrestris and R. erythropolis nutrient media it was incorporated into fatty acids to give rise to tert-butyl fatty acids (t-FAs). In addition, in R. erythropolis, pivalic acid was transformed into two starter units, i.e. isobutyric and 2-methylbutyric acid, which served as precursors of corresponding iso-even FAs and anteiso-FAs. In S. avermitilis the biosynthesis also yielded all three branched FAs; apart from this pathway, both pivalic and 2-methylbutyric acids were incorporated into the antibiotic avermectin. PMID:21450004

  18. Directional Lapped Transforms for Image Coding

    Microsoft Academic Search

    Jizheng Xu; Feng Wu; Jie Liang; Wenjun Zhang

    2008-01-01

    This paper presents a scheme to design directional lapped transforms. Lapped transforms can be factorized into lifting steps. By introducing directional operator into each lifting step, the directional lapped transform is constructed. The directional lapped transform proposed not only preserves the advantages of lapped transforms, it also can represent directional signals more efficiently. An image coding scheme using the directional

  19. Directional Lapped Transforms for Image Coding

    Microsoft Academic Search

    Jizheng Xu; Feng Wu; Jie Liang; Wenjun Zhang

    2010-01-01

    In this paper, we present the design of directional lapped transforms for image coding. A lapped transform, which can be implemented by a prefilter followed by a discrete cosine transform (DCT), can be factorized into elementary operators. The corresponding directional lapped transform is generated by applying each elementary operator along a given direction. The proposed directional lapped transforms are not

  20. Formal Transformations and WSL Martin Ward

    E-print Network

    Singer, Jeremy

    Formal Transformations and WSL Part Two Martin Ward STRL Senior Research Fellow Royal Society of Transformations #12;Types of Transformations A Syntactic Transformation changes the syntax of the program but preserves the exact sequence of operations carried out by the program. Many restructuring transformations

  1. Bioconversion of sunflower oil, rapeseed oil and ricinoleic acid by Candida tropicalis M25

    Microsoft Academic Search

    D. Fabritius; H.-J. Schäfer; A. Steinbüchel

    1998-01-01

    Bioconversions of sunflower oil and rapeseed oil in fed-batch cultures fermented with Candida tropicalis M25 were studied. Cofermentations with palmitic acid resulted in successful transformations to different 3-hydroxydioic acids.\\u000a The absolute configuration of the major fermentation product, R-(Z)-3-hydroxy-9-octadecenedioic acid, was determined by comparison of the 1H NMR data with those of an authentic, optically pure compound. Using ricinoleic acid as

  2. Electrochemical sensing of melamine with 3,4-dihydroxyphenylacetic acid as recognition element

    Microsoft Academic Search

    Qian Cao; Hong Zhao; Yujian He; Nan Ding; Jian Wang

    2010-01-01

    A new electrochemical sensor for melamine with 3,4-dihydroxyphenylacetic acid as the recognition element is established. The results of Fourier Transform Infrared (FT-IR) spectra demonstrate that melamine may interact with 3,4-dihydroxyphenylacetic acid to form a complex mainly through the hydrogen-bonding interaction. The electrochemical behavior of 3,4-dihydroxyphenylacetic acid in the presence of melamine was studied. The anodic peak currents of 3,4-dihydroxyphenylacetic acid

  3. Features of the pp60v-src carboxyl terminus that are required for transformation.

    PubMed Central

    Yaciuk, P; Shalloway, D

    1986-01-01

    Analysis of the biological and biochemical activities of pp60recombinant-src proteins encoded by 12 carboxyl-terminal mutants showed that a wide family of alternate src carboxyl termini permit complete transforming and kinase activities. src proteins having carboxyl termini which are up to 10 amino acids longer than that of pp60c-src (17 amino acids longer than that of pp60v-src) still permit transformation. Transformation-positive mutations preserve leucine-516, a residue which is highly conserved in protein-tyrosine kinase sequences; removal causes in vivo protein instability. Successive deletion mutants show that this residue is at the boundary of a region required for kinase activity. pp60src which is truncated just outside this point still transforms cells and binds both pp50 and pp90 cellular proteins. Images PMID:3097514

  4. Conduction-coupled Tesla transformer.

    PubMed

    Reed, J L

    2015-03-01

    A proof-of-principle Tesla transformer circuit is introduced. The new transformer exhibits the high voltage-high power output signal of shock-excited transformers. The circuit, with specification of proper circuit element values, is capable of obtaining extreme oscillatory voltages. The primary and secondary portions of the circuit communicate solely by conduction. The destructive arcing between the primary and secondary inductors in electromagnetically coupled transformers is ubiquitous. Flashover is eliminated in the new transformer as the high-voltage inductors do not interpenetrate and so do not possess an annular volume of electric field. The inductors are remote from one another. The high voltage secondary inductor is isolated in space, except for a base feed conductor, and obtains earth by its self-capacitance to the surroundings. Governing equations, for the ideal case of no damping, are developed from first principles. Experimental, theoretical, and circuit simulator data are presented for the new transformer. Commercial high-temperature superconductors are discussed as a means to eliminate the counter-intuitive damping due to small primary inductances in both the electromagnetic-coupled and new conduction-coupled transformers. PMID:25832281

  5. Conduction-coupled Tesla transformer

    NASA Astrophysics Data System (ADS)

    Reed, J. L.

    2015-03-01

    A proof-of-principle Tesla transformer circuit is introduced. The new transformer exhibits the high voltage-high power output signal of shock-excited transformers. The circuit, with specification of proper circuit element values, is capable of obtaining extreme oscillatory voltages. The primary and secondary portions of the circuit communicate solely by conduction. The destructive arcing between the primary and secondary inductors in electromagnetically coupled transformers is ubiquitous. Flashover is eliminated in the new transformer as the high-voltage inductors do not interpenetrate and so do not possess an annular volume of electric field. The inductors are remote from one another. The high voltage secondary inductor is isolated in space, except for a base feed conductor, and obtains earth by its self-capacitance to the surroundings. Governing equations, for the ideal case of no damping, are developed from first principles. Experimental, theoretical, and circuit simulator data are presented for the new transformer. Commercial high-temperature superconductors are discussed as a means to eliminate the counter-intuitive damping due to small primary inductances in both the electromagnetic-coupled and new conduction-coupled transformers.

  6. [Transformation toughening]. Annual progress report

    SciTech Connect

    Rafa, M.J.

    1993-04-19

    In NiAl, we have succeeded in determining the complete Ginzburg-Landau strain free energy function necessary to model the cubic to tetragonal martensite transformation in a sample of any size. We believe that this is the first time that the parameters of a Ginzburg-Landau functional and the complete strain spinodal for any three-dimensional displacive transformation were used in simulating the transformation near a crack tip under Mode I loading; the transformation pattern and toughening are different from standard transformation toughening theories. Furthermore, the strain spinodal has an approximately conical shape which can be specified by two material dependent experimentally accessible parameters, rather than the ellipsoidal shape in standard theories. Stress induced martensitic transformation in a polycrystalline sample of NiAl was simulated. In the ZrO{sub 2} system, first principles calculations to determine the semi-empirical potentials for simulating the cubic-tetragonal and tetragonal-monoclinic transformations have been started by doing a more elaborate total energy calculation.In the Al{sub 2}0{sub 3} system, we have discovered that the first principles calculations and semi-empirical potentials have just been completed byanother group in England which we will use instead to base our molecular dynamics simulations on.

  7. Combining Curvelet Transform and Wavelet Transform for Image Denoising

    Microsoft Academic Search

    Ying Li; Shengwei Zhang; Jie Hu

    2010-01-01

    \\u000a Wavelet transform has the good characteristic of time-frequency locality and many researches show that it can perform well\\u000a for denoising in smooth and singular areas. But it isn’t suitable for describing the signals, which have high dimensional\\u000a singularities. Curvelet is one of new multiscale transform theories, which possess directionality and anisotropy, and it breaks\\u000a some inherent limitations of wavelet in

  8. Fast computation of wavelet transforms with the extended lapped transform

    Microsoft Academic Search

    H. S. Malvar

    1992-01-01

    The use of the extended lapped transform (ELT) to implement orthogonal wavelet transforms (WTs) is suggested, and a fast algorithm is presented for the ELT-based WT. Its performance is quite close to that of maximally-regular WTs, in terms of regularity, filtering characteristics, and coding gains. The advantage of ELT-based WTs is that they lead to about half the computational complexity

  9. Type-II Bäcklund Transformations via Gauge Transformations

    E-print Network

    A. R. Aguirre; T. R. Araujo; J. F. Gomes; A. H. Zimerman

    2011-12-19

    The construction of type II Backlund transformation for the sine-Gordon and the Tzitzeica-Bullough-Dodd models are obtained from gauge transformation. An infinite number of conserved quantities are constructed from the defect matrices. This guarantees that the introduction of type II defects for these models does not spoil their integrability. In particular, modified energy and momentum are derived and compared with those presented in recent literature.

  10. Heat storage in alloy transformations

    NASA Technical Reports Server (NTRS)

    Birchenall, C. E.; Gueceri, S. I.

    1980-01-01

    The theory of eutectic transformation was examined to find guidelines to the best material combinations to examine. The heats of transformation were measured calorimetrically, and the volume changes of expanding solid mixtures and homogeneous liquid solutions, especially during the transformation between the two states at fixed temperature, were measured by changes in X-ray absorption. Heat flow models appropriate to storage in phase change materials were developed along with efficient calculating procedures so that the relative importance of the problems associated with energy storage density, heat conduction, and similar properties could be assessed.

  11. Spacecraft transformer and inductor design

    NASA Technical Reports Server (NTRS)

    Mclyman, W. T.

    1977-01-01

    The conversion process in spacecraft power electronics requires the use of magnetic components which frequently are the heaviest and bulkiest items in the conversion circuit. This handbook pertains to magnetic material selection, transformer and inductor design tradeoffs, transformer design, iron core dc inductor design, toroidal power core inductor design, window utilization factors, regulation, and temperature rise. Relationships are given which simplify and standardize the design of transformers and the analysis of the circuits in which they are used. The interactions of the various design parameters are also presented in simplified form so that tradeoffs and optimizations may easily be made.

  12. Curvelet transform with adaptive tiling

    NASA Astrophysics Data System (ADS)

    Al-Marzouqi, Hasan; AlRegib, Ghassan

    2012-03-01

    The curvelet transform is a recently introduced non-adaptive multi-scale transform that have gained popularity in the image processing field. In this paper, we study the effect of customized tiling of frequency content in the curvelet transform. Specifically, we investigate the effect of the size of the coarsest level and its relationship to denoising performance. Based on the observed behavior, we introduce an algorithm to automatically choose the optimal number of decompositions. Its performance shows a clear advantage, in denoising applications, when compared to default curvelet decomposition. We also examine how denoising is affected by varying the number of divisions per scale.

  13. 3D discrete curvelet transform

    NASA Astrophysics Data System (ADS)

    Ying, Lexing; Demanet, Laurent; Candes, Emmanuel

    2005-08-01

    In this paper, we present the first 3D discrete curvelet transform. This transform is an extension to the 2D transform described in Candes et al..1 The resulting curvelet frame preserves the important properties, such as parabolic scaling, tightness and sparse representation for singularities of codimension one. We describe three different implementations: in-core, out-of-core and MPI-based parallel implementations. Numerical results verify the desired properties of the 3D curvelets and demonstrate the efficiency of our implementations.

  14. Program reusability through program transformation. [Transforming LISP into FORTRAN

    SciTech Connect

    Boyle, J.M.; Muralidharan, M.N.

    1984-09-01

    How can a program written in pure applicative LISP be reused in a Fortran environment. One answer is by automatically transforming it from LISP into Fortran. This paper discusses a practical application of this technique - one that yields an efficient Fortran program. This process is viewed as an example of abstract programming, in which the LISP program constitutes an abstract specification for the Fortran version. The idea of strategy - a strategy for getting from LISP to Fortran - is basic to designing and applying the transformations. One strategic insight is that the task is easier if the LISP program is converted to recursive Fortran, and then the recursive Fortran program is converted to nonrecursive standard Fortran. Another strategic insight is that much of the task can be accomplished by converting the program from one canonical form to another. Developing a strategy also involves making various implementation decisions. One advantage of program-transformation methodology is that it exposes such decisions for examination and review. Another is that it enables optimizations to be detected and implemented easily. Once a strategy has been discovered, it can be implemented by means of rewrite-rule transformations using the TAMPR program transformation system. The transformational approach to program reuse based on this strategy has a measure of elegance. It is also practical - the resulting Fortran program is 25% faster than its compiled LISP counterpart, even without extensive optimization. 46 references, 25 figures.

  15. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

    Microsoft Academic Search

    Deyang Lü; Xueyuan Cao; Shunxue Tang; Xia Tian

    2000-01-01

    Gene encoding sulphur amino acid-rich protein (HNP) androl genes were transferred intoMedicago sativa L (alfalfa) mediated byAgrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues\\u000a were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency\\u000a in alfalfa. Production of co-transformed plants with

  16. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes.

    PubMed

    Lü, D; Cao, X; Tang, S; Tian, X

    2000-08-01

    Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties. PMID:18726342

  17. Microwave Structure for the Propiolic Acid-Formic Acid Complex

    NASA Astrophysics Data System (ADS)

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

    2013-10-01

    New microwave spectra were measured to obtain rotational constants and centrifugal distortion constants for the DCCCOOH···HOOCH and HCCCOOD···DOOCH isotopologues. Rotational transitions were measured in the frequency range of 4.9-15.4 GHz, providing accurate rotational constants, which, combined with previous rotational constants, allowed an improved structural fit for the propiolic acid-formic acid complex. The new structural fit yields reasonably accurate orientations for both the propiolic and formic acid monomers in the complex and more accurate structural parameters describing the hydrogen bonding. The structure is planar, with a positive inertial defect of - = 1.33 amu Å2. The experimental structure exhibits a greater asymmetry for the two hydrogen bond lengths than was obtained from the ab initio mp2 calculations. The best-fit hydrogen bond lengths have an r(O1-H1···O4) of 1.64 Å and an r(O3-H2···O2) of 1.87 Å. The average of the two hydrogen bond lengths is rav(exp) = 1.76 Å, in good agreement with rav(theory) = 1.72 Å. The center of mass separation of the monomers is RCM = 3.864 Å. Other structural parameters from the least-squares fit using the experimental rotational constants are compared with theoretical values. The spectra were obtained using two different pulsed beam Fourier transform microwave spectrometers.

  18. Heterogeneous organic acid uptake on soot surfaces

    E-print Network

    Levitt, Nicholas Paul

    2009-05-15

    number of carboxylic acids and soot from diferent fuel sources and formation mechanisms. A low presure fast flow reactor was used to control the contact betwen the solid phase soot and gas phase organics, while chemical ionization-mas spectrometry... Density Functional Theory EC Elemental Carbon FTIR Fourier Transform Infrared Spectroscopy ID Inner Diameter ID-CIMS Ion Drift-Chemical Ionization Mas Spectrometry IR Infrared LYP Le, Yang, and Par MCT Mercury Cadmium Teluride MIR...

  19. New algorithms for Abel inversions and Hankel transforms

    Microsoft Academic Search

    E. Hansen

    1983-01-01

    New algorithms are presented for the Abel and Hankel transforms. Forward and inverse Abel transforms are computed recursively via state variable modeling of the transform kernels. The Hankel transform is computed as the Fourier transform of a forward Abel transform.

  20. BIOLISTIC TRANSFORMATION OF SUGAR BEET CELL SUSPENSIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nonproprietary sugar beet transformation methods are plagued by low transformation frequencies and lack of reproducibility. In efforts to optimize the methods, we established highly embryogenic sugar beet cell suspension cultures for transformation by the particle bombardment method. Callus obtain...

  1. Wavelet Transforms in Time Series Andrew Tangborn

    E-print Network

    Kalnay, Eugenia

    . What is a Wavelet? 3. Continuous and Discrete Wavelet Transforms 4. Construction of Wavelets through compression, efficient representation. 8. Soft Thresholding. 9. Continuous Transform - Morlet Wavelet 10Wavelet Transforms in Time Series Analysis Andrew Tangborn Global Modeling and Assimilation Office

  2. TRANSFORMING ACADEMIA Historical Developments, Contemporary Perspectives and

    E-print Network

    Li, Mo

    ISyE 8803A TRANSFORMING ACADEMIA Historical Developments, Contemporary Perspectives independence and this organizational structure represent the first major transformation of academia. These characteristics of academia have persisted for over 900 years and seem immutable. Yet, notable transformations

  3. The Fast Lifting Wavelet Transform

    NSDL National Science Digital Library

    Valens, C.

    A tutorial on wavelet filters aimed at engineers. Focusses on "lifting," a technique for creating a general framework to design filters for every possible wavelet transform. May be read online or downloaded in PostScript format.

  4. Barley Transformation Using Biolistic Techniques

    NASA Astrophysics Data System (ADS)

    Harwood, Wendy A.; Smedley, Mark A.

    Microprojectile bombardment or biolistic techniques have been widely used for cereal transformation. These methods rely on the acceleration of gold particles, coated with plasmid DNA, into plant cells as a method of directly introducing the DNA. The first report of the generation of fertile, transgenic barley plants used biolistic techniques. However, more recently Agrobacterium-mediated transformation has been adopted as the method of choice for most cereals including barley. Biolistic procedures are still important for some barley transformation applications and also provide transient test systems for the rapid checking of constructs. This chapter describes methods for the transformation of barley using biolistic procedures and also highlights the use of the technology in transient assays.

  5. Lightweight, high-frequency transformers

    NASA Technical Reports Server (NTRS)

    Schwarze, G. E.

    1983-01-01

    The 25-kVA space transformer was developed under contract by Thermal Technology Laboratory, Buffalo, N. Y. The NASA Lewis transformer technology program attempted to develop the baseline technology. For the 25-kVA transformer the input voltage was chosen as 200 V, the output voltage as 1500 V, the input voltage waveform as square wave, the duty cycle as continuous, the frequency range (within certain constraints) as 10 to 40 kHz, the operating temperatures as 85 deg. and 130 C, the baseplate temperature as 50 C, the equivalent leakage inductance as less than 10 micro-h, the operating environment as space, and the life expectancy as 10 years. Such a transformer can also be used for aircraft, ship and terrestrial applications.

  6. Chinese Passives: Transformational or Lexical?

    E-print Network

    Zhang, Jiuwu; Wen, Xiaohong

    1989-01-01

    There are two types of passive constructions in Chinese. Type I is a syntactic passive since it is derived through a transformational rule. Type II is a lexical passive. It has certain properties in common with the predicate ...

  7. ConcepTest: Transform Boundary

    NSDL National Science Digital Library

    A and B are located on two plates separated by a transform boundary (see diagram below). What direction is plate B moving if plate A is moving northeast (NE)? a. northeast b. northwest c. southwest d. southeast

  8. Phase transformations in engineering materials

    SciTech Connect

    Bourke, M.A.M.; Lawson, A.C. [Los Alamos National Lab., NM (United States); Dunand, D.C. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering; Priesmeyer, H.G. [GKSS-Forschungszentrum Geesthacht GmbH (Germany)

    1996-06-01

    Phase transformations in engineering materials are inevitably related to mechanical behavior and are often precursors to residual stress and distortion. Neutron scattering in general is a valuable tool for studying their effects, and pulsed neutrons are of special value, because of the inherently comprehensive crystallographic coverage they provide in each measurement. At the Manuel Lujan neutron scattering center several different research programs have addressed the relationships between phase transformation/mechanical behavior and residual strains. Three disparate examples are presented; (1) stress induced transformation in a NiTi shape memory alloy, (2) cryogenically induced transformation in a quenched 5180 steel, and (3) time resolved evolution of strain induced martensite in 304 stainless steel. In each case a brief description of the principle result will be discussed in the context of using neutrons for the measurement.

  9. Correctness-preserving program transformations

    Microsoft Academic Search

    Susan L. Gerhart

    1975-01-01

    This paper extends the predicate calculus formalization of the partial correctness properties of programs (Ki, Go) to include the preservation of correctness under program transformations. The general notion of \\

  10. On the Laplace transform for distributions

    NASA Technical Reports Server (NTRS)

    Price, D. B.

    1975-01-01

    A new characterization of the Laplace transform for Schwartz distributions is developed, using sequences of linear transformations on the space of distributions. The standard theorems on analyticity, uniqueness and invertibility of the transform are proved, using the new characterization as the definition of the Laplace transform. It is shown that this sequential definition is equivalent to Schwartz's extension of the ordinary Laplace transform to distributions which he obtained from the Fourier transform.

  11. Biorthogonal and nonuniform lapped transforms for transform coding with reduced blocking and ringing artifacts

    Microsoft Academic Search

    Henrique S. Malvar

    1998-01-01

    New lapped transforms are introduced. The lapped biorthononal transform (LBT) and hierarchical lapped biorthogonal transform (HLBT) are appropriate for image coding, and the modulated HLBT biorthogonal transform (MMLBT) and nonuniform modulated lapped biorthogonal transform (NMLBT) are appropriate for audio coding. The HLBT has a significantly lower computational complexity than the lapped orthogonal transform (LOT), essentially no blocking artifacts, and fewer

  12. Transformation: emergence of the self 

    E-print Network

    Stein, Murray

    1998-01-01

    embodies alchemy, which represents the art of transformation. Symbolically, transmutating lead into gold repre sents the death-rebirth process leading to one's philosopher's stone and authentic living, as Jung experienced at Bollingen where he... base metals into gold. Chemistry could not become a true science until prac titioners of this laboratory sport gave up their dungeons and drag- (10 ) Transformation ons. So the argument goes. Watch those metaphors! This line of thinking certainly...

  13. Electrokinetic effects in power transformers

    Microsoft Academic Search

    J. K. Nelson; M. J. Lee; S. J. Salon

    1992-01-01

    Electrokinetic effects such as static electrification can cause catastrophic failures in large forced-oil-cooled power transformers. Experimental and analytical studies confirm that surface charges can significantly impact dielectric integrity. The project team used a closed-loop oil circulation system and full-scale models of power transformer cooling duct structures to conduct controlled experiments. They measured charge density in the oil-resulting from flow through

  14. Symmetry breaking from Lorentz transformation

    E-print Network

    Bin-Guang Ma

    2005-08-10

    Symmetry breaking is discussed in this paper which comes from the Lorentz transformation of special relativity and changes our view that two relatively moving bodies always have the relative speed equal in magnitude and opposite in direction. An appeal was made for the test of Lorentz transformation in a multimedia environment which has the fundamental significance that it may reveal the origin of symmetry breaking in many physical phenomena.

  15. METABOLISM, MICROFLORA EFFECTS, AND GENOTOXICITY IN HALOACETIC ACID-TREATED CULTURES OF RAT CECAL MICROBIOTA

    EPA Science Inventory

    Haloacetic acids are by-products of drinking water disinfection. Several compounds in this class are genotoxic and have been identified as rodent hepatocarcinogens. Enzymes produced by the normal intestinal bacteria can transform some promutagens and procarcinogens to their bio...

  16. On the broken ray transform

    E-print Network

    Joonas Ilmavirta

    2014-09-26

    This PhD thesis studies the broken ray transform, a generalization of the geodesic X-ray transform where geodesics are replaced with broken rays that reflect on a part of the boundary. The fundamental question is whether this transform is injective. We employ four different methods to approach this question, and each of them gives interesting results. Direct calculation can be used in a ball, where the geometry is particularly simple. If the reflecting part of the boundary is (piecewise) flat, a reflection argument can be used to reduce the problem to the usual X-ray transform. In some geometries one can use broken rays near the boundary to determine the values of the unknown function at the reflector, and even construct its Taylor series. One can also use energy estimates -- which in this context are known as Pestov identities -- to show injectivity in the presence of one convex reflecting obstacle. Many of these methods work also on Riemannian manifolds. We also discuss the periodic broken ray transform, where the integrals are taken over periodic broken rays. The broken ray transform and its periodic version have applications in other inverse problems, including Calder\\'on's problem and problems related to spectral geometry. A more detailed abstract can be found in the PDF file. This version only contains the introductory parts of the thesis. The full thesis also contains five articles.

  17. Neoplastic transformation of human cells

    NASA Technical Reports Server (NTRS)

    Goth-Goldstein, Regine

    1995-01-01

    The goal of this project was to gain a better understanding of the cellular mechanisms of cancer induction by ionizing radiation as a risk assessment for workers subjected to high LET irradiation such as that found in space. The following ions were used for irradiation: Iron, Argon, Neon, and Lanthanum. Two tests were performed: growth in low serum and growth in agar were used as indicators of cell transformation. The specific aims of this project were to: (1) compare the effectiveness of various ions on degree of transformation of a single dose of the same RBE; (2) determine if successive irradiations with the same ion (Ge 600 MeV/u) increases the degree of transformation; (3) test if clones with the greatest degree of transformation produce tumors in nude mice; and (4) construct a cell hybrid of a transformed and control (non-transformed) clone. The cells used for this work are human mammary epithelial cells with an extended lifespan and selected for growth in MEM + 10% serum.

  18. Anaerobic degradation of phthalic acid esters during digestion of municipal solid waste under landfilling conditions

    Microsoft Academic Search

    J. Ejlertsson; U. Meyerson; B. H. Svensson

    1996-01-01

    Anaerobic microorganisms in municipal solid waste samples from laboratory-scale landfill reactors and a pilot-plant biogas digestor were investigated with the aim of assessing their ability to transform four commercially used phthalic acid esters (PAEs) and phthalic acid (PA). The PAEs studied were diethyl phthalate (DEP), butylbenzyl phthalate (BBP), dibutyl phthalate (DBP) and bis(2-ethylhexyl) phthalate (DEHP). No biological transformation of DEHP

  19. Effect of overexpression of Saccharomyces cerevisiae Pad1p on the resistance to phenylacrylic acids and lignocellulose hydrolysates under aerobic and oxygen-limited conditions.

    PubMed

    Larsson, S; Nilvebrant, N O; Jönsson, L J

    2001-10-01

    Lignocellulose hydrolysates, obtained by acid hydrolysis for production of bioethanol, contain, in addition to fermentable sugars, compounds that inhibit the fermenting micro-organism. One approach to alleviate the inhibition problem is to use genetic engineering to introduce increased tolerance. Phenylacrylic acid decarboxylase (Pad1p) catalyses a decarboxylation step, by which aromatic carboxylic acids are converted to the corresponding vinyl derivatives. Pad1p-overexpressing Saccharomyces cerevisiae was cultivated in synthetic medium in the presence of model compounds, ferulic acid [(2 E)-3-(4-hydroxy-3-methoxyphenyl)prop-2-enoic acid] and cinnamic acid [(2 E)-3-phenylprop-2-enoic acid], as well as in a dilute acid hydrolysate of spruce to examine the resistance against fermentation inhibitors. Overexpression of S. cerevisiae phenylacrylic acid decarboxylase (Pad1p) resulted in an improved growth rate and ethanol productivity in the presence of ferulic acid, cinnamic acid, and in a dilute acid hydrolysate of spruce. Vinyl guaiacol (2-methoxy-4-vinylphenol) was identified as a major metabolite of ferulic acid, and dihydroferulic acid [3-(4-hydroxy-3-methoxyphenyl)propanoic acid] was detected under oxygen-limited conditions. Styrene (vinylbenzene) and dihydrocinnamic acid (3-phenylpropanoic acid) were identified as metabolites of cinnamic acid. Transformants overexpressing Pad1p had the ability to convert ferulic and cinnamic acid at a faster rate than a control transformant (PAD(C)) not overexpressing Pad1p. This enabled faster growth for Pad1p-overexpressing transformants under both aerobic and oxygen-limited conditions. Pad1p activity was also studied using non-growing cells. The overexpressing transformants showed approximately tenfold higher activity than PAD(C). The Pad1p overexpressing transformants also showed a 22-25% faster glucose consumption rate, a 40-45% faster mannose consumption rate, and a 24-29% faster ethanol production rate in the dilute acid hydrolysate of spruce. PMID:11693915

  20. Secoiridoids and antifungal aromatic acids from Gentiana algida.

    PubMed

    Tan, R X; Wolfender, J L; Ma, W G; Zhang, L X; Hostettmann, K

    1996-01-01

    Fractionation of an aqueous acetone extract of the whole herb of Gentiana algida gave one new [2'-(o,m-dihydroxybenzyl)sweroside] and five known secoiridoids, together with anofinic acid, fomannoxin acid, sitosterol, daucosterol, stigmasterol, oleanolic acid, orientin and gentianose. The structures were determined by spectral methods and a few chemical transformations. Anofinic acid and fomannoxin acid were found to be active against Cladosporium cucumerinum, a plant pathogenic fungus. Preliminary structure-activity studies indicated that the presence of carboxylic moieties in these acids was presumably a precondition for activity, whereas their methyl esters, inactive to the fungus, were active against the human pathogenic yeast Candida albicans. The chemotaxonomic significance of the isolates is discussed briefly. PMID:8588862