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1

An Abstracting Transformation for Amino Acid Polymorphism  

E-print Network

An Abstracting Transformation for Amino Acid Polymorphism Anthony M. Castaldo, PhD Research three nucleotide se- quences (a codon) into amino acids: Amino Acid (or signal) Codons A (Alanine) GCT believe what is important is the sequence of amino acids produced, and because amino acids average about

Texas at San Antonio, University of

2

Synthesis, characterization, and antitumor activity of amine platinum(II) and (IV) tellurate complexes.  

PubMed

A series of novel water-soluble amine platinum (II) tellurate complexes of the type (A)Pt(II) [TeO2(OH)4], where A = 1,2-diaminocyclohexane (DACH), 1,1-bis(aminomethyl)cyclohexane (AMCH), ethylenediamine (en), or cyclopentylamine (cpa), were prepared either by the reaction of amineplatinum (II) sulfate with barium tellurate or by a direct reaction of (A)Pt(OH)2 with telluric acid. Oxidation of the amine platinum(II) tellurate produced amine platinum(IV) tellurate (A)Pt(IV)trans(Z) [TeO2(OH)4] complexes, where Z = OH or Cl, following oxidation with hydrogen peroxide or with chlorine gas, respectively. Complexes were characterized by elemental analysis, and IR and 195Pt NMR spectroscopy. Against i.p. murine leukemia cells in vivo, some of the complexes displayed good antitumor activity when administered intraperitoneally (i.p.) on days 1, 5, and 9 at their optimal doses. Pt(II) complexes containing R,R-DACH, S,S-DACH, R,R-S,S-DACH, or AMCH produced %T/C of 147 to 288 whereas cis-DACH, en, and cpa complexes were inactive. In the Pt(IV) series, the R,R-DACH complex with axial Cl was highly active (%T/C = 371, 40% cures) compared with the complex with axial OH (%T/C = 135). PMID:8169608

Khokhar, A R; Xu, Q; Siddik, Z H

1994-03-01

3

The bacterial transformation of abietic acid  

PubMed Central

An Alcaligenes species, which was isolated from soil, can utilize abietic acid as its sole carbon source. During growth, the bacterium transforms abietic acid into 5?-hydroxyabietic acid (I, R=OH), a product considered to be 7?-hydroxy-13-isopropyl-8?-podocarp-13-en-15-oic acid (II, R=H) and a compound, C20H28O3, which is believed to be an epoxy-?-lactone. PMID:5665894

Cross, B. E.; Myers, P. L.

1968-01-01

4

Transformation of some hydroxy amino acids to other amino acids  

Microsoft Academic Search

It has been observed that ß-hydroxy-a-amino acids are transformed into other amino acids, when heated in dilute solutions with phosphorous acid, phosphoric acid or their ammonium salts. It has been shown that as in the case of previously reported glycine-aldehyde reactions, glycine also reacts with acetone to give ß-hydroxyvaline under prebiologically feasible conditions. It is suggested, therefore, that the formation

A. S. U. Choughuley; A. S. Subbaraman; Z. A. Kazi; M. S. Chadha

1975-01-01

5

Transformation of some hydroxy amino acids to other amino acids  

Microsoft Academic Search

It has been observed that beta-hydroxy-alpha-amino acids are transformed into other amino acids, when heated in dilute solutions with phosphorous acid, phosphoric acid or their ammonium salts. It has been shown that as in the case of previously reported glycine-aldehyde reactions, glycine also reacts with acetone to give beta-hydroxyvaline under prebiologically feasible conditions. It is suggested, therefore, that the formation

A. S. U. Choughuley; A. S. Subbaraman; Z. A. Kazi; M. S. Chadha

1975-01-01

6

Genetic Evidence for a Molybdopterin-Containing Tellurate Reductase  

PubMed Central

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

Theisen, Joanne; Zylstra, Gerben J.

2013-01-01

7

TelFit: Fitting the telluric absorption spectrum  

NASA Astrophysics Data System (ADS)

TelFit calculates the best-fit telluric absorption spectrum in high-resolution optical and near-IR spectra. The best-fit model can then be divided out to remove the telluric contamination. Written in Python, TelFit is essentially a wrapper to LBLRTM, the Line-By-Line Radiative Transfer Model, and simplifies the process of generating a telluric model.

Gullikson, Kevin

2014-05-01

8

Mineralogical transformations controlling acid mine drainage chemistry  

SciTech Connect

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.

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

2009-05-30

9

Mineralogical transformations controlling acid mine drainage1 T. Peretyazhko*1  

E-print Network

Mineralogical transformations controlling acid mine drainage1 chemistry2 3 4 5 T. Peretyazhko*1 , J drainage, schwertmannite, mineralogical transformations65 #12;4 1. Introduction66 Acid mine drainage (AMD tetyana.peretyazhko@pnl.gov.35 #12;2 Abstract36 The role of Fe(III) minerals in controlling acid mine

Burgos, William

10

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

NASA Astrophysics Data System (ADS)

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

Neukirch, M.; Garcia, X.

2012-04-01

11

Fluid circulation in the active emerged Asal rift (east Africa, Djibouti) inferred from self-potential and Telluric Telluric prospecting  

NASA Astrophysics Data System (ADS)

In 1996 Self-Potential (SP) and Telluric-Telluric (TT) surveys were performed in the Asal rift, in the Republic of Djibouti, in order to study water circulation through the rift, from Ghoubbet Strait to Asal lake located 11 km Northwest, and at the altitude of 155 m below sea level. SP surveys reveal two main positive anomalies, several kilometres wide, up to 150 mV in amplitude, parallel to the rift and separated by a relatively large (1 km) negative anomaly. The northern anomaly is well centred above the active rift. The central part of the anomaly is cut by a sharp and narrow negative anomaly (200 mV in amplitude, 150 m width) due to a major fault running from Ghoubbet Strait to Asal lake. The two positive anomalies are interpreted by ground seawater flowing toward Asal lake and warmed up during their advance by the strong geothermal flux existing beneath the rift. The negative anomalies are most probably due to large and rapid fluid transfer along faults and high permeable geologic beds bending toward Asal lake. The rapid flow would prevent any large heating of the ground water. The largest negative anomaly, which isolates the two positive ones, gives new valuable information on the tectonics. The extension of the northern positive anomaly to the Southwest is stopped by a fault located about 1 km to the North of a normal fault considered until now, as a major rift structure. The 16 Telluric-Telluric (TT) surveys point out three behaviours of the telluric field. Near Ghoubbet Strait and inland the telluric field is well polarised in a N90-100°E direction and the amplitude expresses a medium to a low resistivity beneath the recording sites. This pattern is the signature of the coast effect and the regional polarisation of the field. Along normal faults bordering the rift the SE-NW polarisation seems to be controlled by the rift tectonics. Inside the rift the telluric field becomes weaker, indicating a decay of the resistivity. In the central part of the rift the telluric field amplitude becomes 1/3 of the generally recorded amplitude and the polarisation cannot be estimated. It is corresponding to very low resistive areas in agreement with high positive SP values.

Mlynarski, M.; Zlotnicki, J.

2001-09-01

12

PROPRITS DES LAMES VAPORES DE TELLURE Par T. SAKURAI,  

E-print Network

by absorbing various kind of gas. LE JOURNAL DE PHYSIQUE ET LE RADIUM TOME 17, MARS 1956, Le tellure est de réflexion. Dans ces expériences, des plaques polies de KCI et KBr furent utilisées comme sup- port

Paris-Sud XI, Université de

13

R-band Radial Velocity Measurements Using Telluric Line Calibration  

NASA Astrophysics Data System (ADS)

The absorption cell technique is modified to use the telluric O2 and water vapor bands found between ˜5800-8800 ?, allowing access to the increased red flux of low-mass and evolved stars. We carry out a mock planet search of RV stable M dwarfs made with the High Resolution Spectrograph of the Hobby-Eberly Telescope. Radial velocities are measured by forward modeling the observations using model telluric spectra optimized to each epoch. Measurements are tested using a small number of ˜2 ? blocks and compared to analogous measurements made through an iodine cell. This sample of blocks is extrapolated to the full wavelength range, yielding a precision of ˜30 m s-1 with telluric calibration. We obtain a similarly modest precision with iodine calibration and both results may be improved by increasing the signal-to-noise ratio, with an expected final precision of <10 m s-1. This technique is ideal for red stars that have a moderate amount of intrinsic RV noise, such as K giants and flaring M dwarfs.

Gettel, Sara; Wright, J.; Bender, C. F.; Wang, X.; Zhao, M.; Wolszczan, A.

2013-01-01

14

Pyruvic acid production using methylotrophic yeast transformants as catalyst  

Microsoft Academic Search

Permeabilized transformants of the methylotrophic yeasts Hansenula polymorpha and Pichia pastoris which express both the glycolate oxidase ((S)-2-hydroxyacid oxidase, EC 1.1.3.15) from spinach and an endogenous catalase (EC 1.11.1.6) have been used as catalysts for the oxidation of l-lactic acid to pyruvic acid. Oxidations of the sodium or ammonium salts of l-lactate at concentrations of up to 1.06 M were

Amy Eisenberg; John E. Seip; John E. Gavagan; Mark S. Payne; David L. Anton; Robert DiCosimo

1997-01-01

15

Cholesterol: Vitamin C Controls Its Transformation to Bile Acids  

Microsoft Academic Search

Cholesterol accumulates in the blood serum and in the liver of guinea pigs with chronic latent vitamin C deficiency. The reason for this is the decreased rate of transformation of cholesterol to bile acids in the liver of animals deficient in vitamin C. A significant direct correlation exists between the vitamin C concentration in the liver and the rate of

Emil Ginter

1973-01-01

16

Synthetic transformations of higher terpenoids: XV. Transformations of azlactone derived from 16-formyllambertianic acid methyl ester  

Microsoft Academic Search

Condensation of 16-formyllambertianic acid methyl ester with hippuric acid gave methyl 15,16-epoxy-16-[(4Z)-5-oxo-2-phenyl-4,5-dihydrooxazol-4-ylidenemethyl]labda-8(20),13(16),14-trien-19-oate\\u000a which underwent ready transformation into 2-benzoylamino-3-(2-furyl)acrylic acid of the labdanoid series. Reactions of the\\u000a diterpenoid azlactone with amines and ?-amino acid esters led to the formation of the corresponding carbamoylvinylbenzamides\\u000a and N-(2-benzoylaminoacryloyl) amino acid esters, and furylacrylic acid hydrazides were formed in reactions with hydrazines. Cyclization\\u000a of the

Yu. V. Kharitonov; E. E. Shul’ts; M. M. Shakirov; G. A. Tolstikov

2007-01-01

17

Mechanism of Inactivation of Transforming Deoxyribonucleic Acid by X Rays  

PubMed Central

Transforming deoxyribonucleic acid (DNA) from Haemophilus influenzae was exposed to X rays either in phosphate buffer or in 10% yeast extract. Relations between determinations of biological inactivation, DNA uptake by competent H. influenzae, integration of DNA into the competent cell genome, and induced single-and double-strand breaks indicate that transforming DNA is inactivated by the direct and the indirect effect of X radiation primarily because integration of DNA is prevented as a result of the production of double-strand breaks. PMID:5313645

Randolph, M. L.; Setlow, Jane K.

1971-01-01

18

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

NASA Astrophysics Data System (ADS)

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.

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

2014-05-01

19

A Comparison of Telluric Current and Magnetic Field Observations in the Arctic Ocean  

Microsoft Academic Search

Simultaneous observations of the H and D components of the magnetic field and of two components of telluric current were made on Arctic drifting station Charlie during the winter of 1959-1960 and on station Arlis I in early 1961. The telluric current and mag- netometer data show a striking similarity. Spectral analysis showed the two types of data to have

Daniel W. Swift; Victor P. Hessler

1964-01-01

20

Fluid circulation in the active emerged Asal rift (east Africa, Djibouti) inferred from self-potential and Telluric–Telluric prospecting  

Microsoft Academic Search

In 1996 Self-Potential (SP) and Telluric–Telluric (TT) surveys were performed in the Asal rift, in the Republic of Djibouti, in order to study water circulation through the rift, from Ghoubbet Strait to Asal lake located 11km Northwest, and at the altitude of 155m below sea level. SP surveys reveal two main positive anomalies, several kilometres wide, up to 150mV in

M. Mlynarski; J Zlotnicki

2001-01-01

21

Correcting for Telluric Absorption: Methods, Case Studies, and Release of the TelFit Code  

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

22

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

PubMed

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

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

2014-12-01

23

Taxonomy of the Neisseriae: Deoxyribonucleic Acid Base Composition, Interspecific Transformation, and Deoxyribonucleic Acid Hybridization  

Microsoft Academic Search

Deoxyribonucleic acid (DNA) base composition, intergenic transformation efficiency, and DNA hybridization were used to determine the relatedness of a variety of established or proposed species of Neisseria and Branhamella. These studies indicated that these bacteria form three genetic groupings. Group I, comprised of N. meningitidis, N. gonorrhoeae, N. subflava, N. flava, N. perflava, N. sicca, N. mucosa, N. cinerea, N.

CAROLYN HOKE; NEYLAN A. VEDROS

1982-01-01

24

Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based S. Al-Khattaf*  

E-print Network

Catalytic Transformation of Toluene over High Acidity Y-Zeolite Based Catalyst S. Al in the temperature range of 400-500o C to understand the transformation of toluene over high acidity Y-based zeolite Abstract Catalytic transformation of toluene has been investigated over Y-zeolite based catalysts

Al-Khattaf, Sulaiman

25

Iron transformations induced by an acid-tolerant Desulfosporosinus species.  

PubMed

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

Bertel, Doug; Peck, John; Quick, Thomas J; Senko, John M

2012-01-01

26

Iron Transformations Induced by an Acid-Tolerant Desulfosporosinus Species  

PubMed Central

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

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

2012-01-01

27

Monomethylarsonous acid induces transformation of human bladder cells  

SciTech Connect

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.

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

28

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

Microsoft Academic Search

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

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

2004-01-01

29

Fungal transformation and schistosomicidal effects of pimaradienoic acid.  

PubMed

The schistosomicidal effects of pimaradienoic acid (PA) and two derivatives, obtained by fungal transformation in the presence of Aspergillus ochraceus, were investigated. PA was the only compound with antischistosomal activity among the three diterpenes studied, with the ability to significantly reduce the viability of the parasites at concentrations ranging from 25 to 100 ?M. PA also promoted morphological alterations of the tegument of Schistosoma mansoni, separated all the worm couples, and affected the production and development of eggs. Moreover, this compound was devoid of toxicity toward human fibroblasts. In a preliminary in vivo experiment, PA at a dose of 100 mg/kg significantly diminished the number of parasites in infected Balb/c mice. Taken together, these results show that PA may be potentially employed in the discovery of novel schistosomicidal agents, and that diterpenes are an important class of natural compounds for the investigation of agents capable of fighting the parasite responsible for human schistosomiasis. PMID:22899607

Porto, Thiago S; da Silva Filho, Ademar A; Magalhães, Lizandra G; dos Santos, Raquel A; Furtado, Niege A J C; Arakawa, Nilton S; Said, Suraia; de Oliveira, Dionéia C R; Gregório, Luiz E; Rodrigues, Vanderlei; Veneziani, Rodrigo C S; Ambrósio, Sérgio R

2012-08-01

30

Dinuclear manganese centers in the manganese-lead-tellurate glasses.  

PubMed

FTIR, UV-VIS and EPR spectra of manganese doped lead-tellurate glasses with composition xMnO·(100-x)[4TeO2·PbO2] where x=0, 1, 5, 10, 20, 30, 40mol% have been studied. The FTIR spectra show the formation of the Mn-O-Pb and Mn-O-Te bridging bonds by increasing of MnO concentration. The UV-VIS spectra show the Mn(+3) species exhibit pronounced absorption, which masks the Mn(+2) spin-forbidden absorption bands when Mn(+2) ions are in high concentrations in these glasses. The EPR spectra exhibit resonance signals characteristic of Mn(+2) ions. The resonance signal located at g?2 is due to Mn(+2) ions in an environment close to octahedral symmetry, whereas the resonance at g?4.3 and 3.3 are attributed to the rhombic surroundings of the Mn(+2) ions. The increase in the MnO content gives rise to absorption at g?2.4 and the paramagnetic ions are involved in dinuclear manganese centers. PMID:21498108

Rada, S; Dehelean, A; Culea, M; Culea, E

2011-07-01

31

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

DOEpatents

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

Meyerowitz, Elliott M. (Pasadena, CA); Chang, Caren (Pasadena, CA); Bleecker, Anthony B. (Madison, WI)

2001-01-01

32

Impact of micro-telluric lines on precise radial velocities and its correction  

NASA Astrophysics Data System (ADS)

Context. In the near future, new instruments such as ESPRESSO will arrive, allowing us to reach a precision in radial velocity measurements on the order of 10 cm s-1. At this level of precision, several noise sources that until now have been outweighed by photon noise will start to contribute significantly to the error budget. The telluric lines that are not neglected by the masks for the radial velocity computation, here called micro-telluric lines, are one such noise source. Aims: In this work we investigate the impact of micro-telluric lines in the radial velocities calculations. We also investigate how to correct the effect of these atmospheric lines on radial velocities. Methods: The work presented here follows two parallel lines. First, we calculated the impact of the micro-telluric lines by multiplying a synthetic solar-like stellar spectrum by synthetic atmospheric spectra and evaluated the effect created by the presence of the telluric lines. Then, we divided HARPS spectra by synthetic atmospheric spectra to correct for its presence on real data and calculated the radial velocity on the corrected spectra. When doing so, one considers two atmospheric models for the synthetic atmospheric spectra: the LBLRTM and TAPAS. Results: We find that the micro-telluric lines can induce an impact on the radial velocity calculation that can already be close to the current precision achieved with HARPS, and so its effect should not be neglected, especially for future instruments such as ESPRESSO. Moreover, we find that the micro-telluric lines' impact depends on factors, such as the radial velocity of the star, airmass, relative humidity, and the barycentric Earth radial velocity projected along the line of sight at the time of the observation. Appendix A is available in electronic form at http://www.aanda.org

Cunha, D.; Santos, N. C.; Figueira, P.; Santerne, A.; Bertaux, J. L.; Lovis, C.

2014-08-01

33

Monitoring of molecular transformations in acid-base reactions by evolving factor analysis of Fourier transform infrared spectral data  

Microsoft Academic Search

An evolving factor analysis procedure with concentration constraints (gradient concentration window) was applied to the analysis of data sets of aqueous Fourier transform infrared (FT-IR) spectra of carboxylic acids (acetic, malonic and succinic acids) collected in experiments with varying pH. Besides the calculation of the number of acid-base systems, this procedure allowed the calculation of the FT-IR spectra of the

Adélio A. S. C. Machado; César J. S. Oliveira

1996-01-01

34

Differential Effects of Temperature on Natural Transformation to Erythromycin and Nalidixic Acid Resistance in Campylobacter coli  

Microsoft Academic Search

Campylobacter jejuni and Campylobacter coli are naturally competent, but limited information exists on the impact of environmental conditions on transformation. In this study, we investigated the impact of tempera- ture and microaerobic versus aerobic atmosphere on transformation of C. coli to erythromycin and nalidixic acid resistance. Frequency of transformation was not significantly different between microaerobic (5 to 10% CO2) and

Joo-Sung Kim; Jae-Won Kim; S. Kathariou

2008-01-01

35

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

Microsoft Academic Search

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

Robert H. Schiestl; R. Daniel Gietz

1989-01-01

36

Dissimilatory reduction and transformation of ferrihydrite-humic acid coprecipitates.  

PubMed

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

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

2013-12-01

37

Oleanolic acid and ursolic acid inhibit proliferation in transformed rat hepatic oval cells  

PubMed Central

AIM: To investigate H2O2-induced promotion proliferation and malignant transformation in WB-F344 cells and anti-tumor effects of ursolic acid (UA) and oleanolic acid (OA). METHODS: WB-F344 cells were continuously exposed to 7 x 10-7 mol/L H2O2 for 21 d. Observations of cell morphology, colony formation rates, flow cytometric analysis of cell cycle changes and aneuploidy formation indicated that H2O2 was able to induce malignant transformation of WB-F344 cells. We treated malignantly transformed WB-F344 cells with 4 ?mol/L OA or 8 ?mol/L UA for 72 h and analyzed the cell cycle distribution by flow cytometry. RESULTS: MTT assay showed that 7 x 10-7 mol/L H2O2 decreased G1 phase subpopulation from 73.8% to 49.6% compared with the control group, and increased S phase subpopulation from 14.5% to 31.8% (P < 0.05 vs control group). Cell morphology showed that nucleus to cytoplasm ratio increased, many mitotic cells, prokaryotes and even tumor giant cells were shown in H2O2-induced WB-F344 cells. Fluorescence activated cell sorting analysis showed that WB-F344 cell aneuploidy increased to 12% following H2O2 treatment. Flow cytometric analysis of the transformed WB-F344 cells following treatment with OA (4 ?mol/L) and UA (8 ?mol/L) showed that OA increased G1 subpopulation to 68.6%, compared to 49.7% in unexposed cells. UA increased G1 subpopulation to 67.4% compared to 49.7% in unexposed cells (P < 0.05 vs H2O2 model group). CONCLUSION: H2O2 causes the malignant transformation of WB-F344 cells. OA and UA exert anti-tumor effects by inhibiting the proliferation in malignantly transformed WB-F344 cells. PMID:24574810

Han, Yu-Ying; Xue, Xiao-Wei; Shi, Zheng-Ming; Wang, Peng-Yan; Wu, Xin-Rui; Wang, Xue-Jiang

2014-01-01

38

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

PubMed

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

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

2012-11-20

39

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

USGS Publications Warehouse

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.

Pritchard, J.I.

1965-01-01

40

Possible influence of telluric current on seismicity of the Earth's crust in seismoactive zones  

NASA Astrophysics Data System (ADS)

A physical model is proposed for the possible effect of telluric currents on macrofracturing in the Earth's crust and the triggering of earthquakes via the interaction of telluric currents with the geomagnetic field. For implementation of the considered processes, a an escalated regime due to positive feedback between the decrease in electrical conductivity of the developing earthquake source and the increases in current and pressure in this source was established. Estimates of characteristic earthquake-triggering time that agree with the experimental data were obtained. The model explains the interrelationship between some observed electromagnetic phenomena and earthquake development processes in seismoactive zones.

Trenkin, A. A.

2015-01-01

41

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

SciTech Connect

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

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

2000-02-01

42

Prostaglandin Endoperoxides. Novel Transformations of Arachidonic Acid in Human Platelets  

Microsoft Academic Search

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

Mats Hamberg; Bengt Samuelsson

1974-01-01

43

In vitro transformation of chenodeoxycholic acid and ursodeoxycholic acid by human intestinal flora, with particular reference to the mutual conversion between the two bile acids  

Microsoft Academic Search

Nine fecal samples from four healthy subjects were examined for their ability to transform chenodeoxy- cholic acid (CDCA) and ursodeoxycholic acid (UDCA) in in vitro anaerobic broth cultures. Seven samples converted CDCA and UDCA into each other (more than 50% of CDCA was converted into UDCA while 10% or less of UDCA was converted into CDCA), and produced 7-keto-lithocholic acid

Seiju Hirano; Noriyuki Masuda; Hiroshi Od

44

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

PubMed

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

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

2013-07-01

45

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

Microsoft Academic Search

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

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

1993-01-01

46

Mössbauer spectra of 125Te in Europium tellurate between 20 and 295 K  

NASA Astrophysics Data System (ADS)

125Te Mössbauer spectra of “anti-glass” europium tellurate Eu 0.59Te 0.41O 1.72?0.28 were studied at 20, 60 and 295 K. Temperature dependent hyperfine parameters and resonant absorption intensities are interpreted in terms of anisotropic thermal vibration of Te and of some admixture of Te VI

Binczycka, H.; Hafner, S. S.; Stanek, J.; Trömel, M.

1988-08-01

47

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

NASA Astrophysics Data System (ADS)

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

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

2015-04-01

48

Crystal transformation from the ?- to the ?-form upon tensile drawing of poly( l-lactic acid)  

Microsoft Academic Search

A film of poly(l-lactic acid) (PLLA) consisting of highly oriented ? crystals was uniaxially drawn by tensile force. The effects of the draw ratio (DR), draw temperature (Td), and draw stress on the crystal\\/crystal transformation from the ?- to the ?-form crystals were studied. At the initial stage of drawing, the highly oriented ? crystals of the starting film transformed

Kazuyo Takahashi; Daisuke Sawai; Takafumi Yokoyama; Tetsuo Kanamoto; Suong-Hyu Hyon

2004-01-01

49

Microbial transformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans.  

PubMed

Microbial biotransformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans AS 3.1207 was carried out, and totally four transformed products were isolated. On the basis of the extensive spectral data, their structures were characterized as 7?-hydroxy-11-keto-boswellic acid (1), 7?,30-dihydroxy-11-keto-boswellic acid (2), 7?,16?-dihydroxy-3-acetyl-11-keto-boswellic acid (3), and 7?,15?,21?-trihydroxy-3-acetyl-11-keto-boswellic acid (4), respectively. Among them, products 1 and 2 are the new compounds. PMID:24168329

Xin, Xiu-Lan; Huo, Hua; Chen, Liang; Li, Jian; Sun, Jiang-Hao; Zheng, Peng-Wu; Sun, Yue; Wu, Zhi-Ming; Xiong, Ying-Hua

2013-11-01

50

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

PubMed

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 X 10(5) 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 100 fold higher frequency of transformation with plasmids containing the 2 microns origin of replication. Single stranded DNA seems to be responsible for the effect since M13 single stranded DNA, as well as RNA, was effective. Boiled carrier DNA did not yield any increased transformation efficiency using spheroplast formation to induce DNA uptake, indicating a difference in the mechanism of transformation with the two methods. PMID:2692852

Schiestl, R H; Gietz, R D

1989-12-01

51

Flux Calibration of Medium Resolution Spectra from 300 nm to 2500 nm — Model Reference Spectra and Telluric Correction  

NASA Astrophysics Data System (ADS)

A procedure to obtain reference spectra for flux standard stars from stellar model atmospheres is described. This procedure allows users to derive instrument response curves from 300 nm to 2500 nm. The technique was developed using X-shooter spectra, but is general and can also be applied to higher resolution spectra. In addition an automatic method has been defined to correct for moderate telluric absorption using telluric model spectra with very high spectral resolution that can easily be adapted to observed data.

Moehler, S.; Modigliani, A.; Freudling, W.; Giammichele, N.; Gianninas, A.; Gonneau, A.; Kausch, W.; Lançon, A.; Noll, S.; Rauch, T.; Vinther, J.

2014-12-01

52

Infrared spectroscopic and DFT investigations of the vanadate-tellurate glasses structures.  

PubMed

Vanadate-tellurate vitreous systems with composition (1-x)TeO(2).xV(2)O(5) where x=0.3 and 0.4 have been prepared by the conventional melt-quench method. The structural aspects have been investigated using FTIR spectroscopy and the density functional theory (DFT) calculations. The present study provides the interesting information concerning devitrification behavior of the vanadate-tellurate vitreous system which occur Te(2)V(2)O(9) crystalline phase. The structure of the heat-treated glasses was found to consist mainly of rings containing [TeO(3)], [TeO(4)], [VO(4)] and some [VO(5)] structural units. PMID:20036190

Rada, S; Rada, M; Culea, E

2010-02-01

53

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

E-print Network

Context: The interaction of the light from astronomical objects with the constituents of the Earth's atmosphere leads to the formation of telluric absorption lines in ground-based collected spectra. Correcting for these lines, mostly affecting the red and infrared region of the spectrum, usually relies on observations of specific stars obtained close in time and airmass to the science targets, therefore using precious observing time. Aims: We present molecfit, a tool for correcting for telluric absorption lines based on synthetic modelling of the Earth's atmospheric transmission. Molecfit is versatile and can be used with data obtained with various ground-based telescopes and instruments. Methods: Molecfit combines a publicly available radiative transfer code, a molecular line database, atmospheric profiles, and various kernels to model the instrument line spread function. The atmospheric profiles are created by merging a standard atmospheric profile representative of a given observatory's climate, of local m...

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

2015-01-01

54

Glass-free low-temperature cofired ceramics: calcium germanates, silicates and tellurates  

Microsoft Academic Search

To reduce the complexity of LTCC systems, and so accelerate the development of LTCC tapes with new functionalities, it is necessary to reduce the number of phases within a particular tape. This can best be done by using glass-free single-phase ceramic systems. We performed a basic characterization of several low-temperature-sintered calcium silicates, germanates and tellurates in order to evaluate their

Matjaz Valant; Danilo Suvorov

2004-01-01

55

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

NASA Astrophysics Data System (ADS)

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.

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

2008-07-01

56

Loss of activity of transforming deoxyribonucleic acid after uptake by Haemophilus influenzae.  

PubMed

Voll, Mary Jane (University of Pennsylvania, Philadelphia), and Sol H. Goodgal. Loss of activity of transforming deoxyribonucleic acid after uptake by Haemophilus influenzae. J. Bacteriol. 90:873-883. 1965.-Transforming deoxyribonucleic acid (DNA) which has been irreversibly removed from solution by competent cells undergoes a progressive loss in marker activity when tested by lysis of the cells and exposure to new recipient cells. The loss of activity is limited and marker-specific, with greater inactivation of those markers with lower efficiencies of transformation. Recipient factors or donor factors which have undergone recombination, as measured by the appearance of linked markers, do not undergo inactivation. The efficiency of transformation can be correlated with the sensitivity of a marker to inactivation after DNA uptake. A mutation which affects the efficiency of transformation is found to increase sensitivity to postuptake inactivation. The rate of inactivation is temperature-dependent. At temperatures of 20 and 45 C, marker inactivation can occur without concomitant recombination. During the uptake process, DNA is retained in an acid-insoluble form, indicating that the fate of Haemophilus influenzae DNA differs from the fate of transforming DNA in pneumococcus. PMID:5294816

Voll, M J; Goodgal, S H

1965-10-01

57

Okadaic acid and trifluoperazine enhance Agrobacterium-mediated transformation in eastern white pine.  

PubMed

Mature zygotic embryos of recalcitrant Christmas tree species eastern white pine (Pinus strobus L.) were used as explants for Agrobacterium tumefaciens strain GV3101-mediated transformation using the uidA (beta-Glucuronidase) gene as a reporter. Influence of the time of sonication and the concentrations of protein phosphatase inhibitor (okadaic acid) and kinase inhibitor (trifluoperazine) on Agrobacterium-mediated transformation have been evaluated. A high transformation frequency was obtained after embryos were sonicated for 45-50 s, or treated with 1.5-2.0 microM okadaic acid or treated with 100-200 microM trifluoperazine, respectively. Protein phosphatase and kinase inhibitors enhance Agrobacterium-mediated transformation in eastern white pine. A 2-3.5-fold higher rate of hygromycin-resistant callus was obtained with an addition of 2 microM okadaic acid or 150 microM trifluoperazine or sonicated embryos for 45 s. Stable integration of the uidA gene in the plant genome of eastern white pine was confirmed by polymerase chain reaction (PCR), Southern and northern blot analyses. These results demonstrated that a stable and enhanced transformation system has been established in eastern white pine and this system would provide an opportunity to transfer economically important genes into this Christmas tree species. PMID:17242943

Tang, Wei; Lin, Jinxing; Newton, Ronald J

2007-05-01

58

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

NASA Astrophysics Data System (ADS)

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

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

2011-10-01

59

Lipoic acid prevents Cr(6+) induced cell transformation and the associated genomic dysregulation.  

PubMed

Investigation of the transcription profile of cells transformed by Cr(6+) in vivo was undertaken. The objective was to elucidate genomic changes underlying the mechanism of action of the carcinogenic dose of Cr(6+)and their prevention using metabolic antioxidant lipoic acid (LA). Cr(6+) was administered intraperitoneally to LPS+TPA challenged Swiss albino mice in host mediated cell transformation assay using peritoneal macrophages in vivo. The cell transforming potential of Cr(6+) test doses was validated by gain of anchorage independent growth potential in soft agar and loss of Fc receptor on target cells. LA was administered in equimolar doses. Compared to non-transformed cells, the gene expression profile of transformed cells was found to be dysregulated substantially and in dose dependent manner. Genes showing down regulation were found to be involved in tumour suppression, apoptosis, DNA repair, and cell-cycle. A similar response was noted in the genes pertaining to immune system, morphogenesis, cell-communication, energy-metabolism, and biosynthesis. The co-administration of lipoic acid prevented the transcription dysregulation and cell transformation by Cr(6+) in vivo. The influenced pathways seem to be crucial for progression as well as mitigation of Cr toxicity; and their response to LA indicated their critical role in mechanism of anti-carcinogenic action of LA. Results are of importance to mitigate Cr(6+) induced occupational cancer hazard. PMID:23608068

Kumar, Sushil; Nigam, Akanksha; Priya, Shivam; Bajpai, Preeti; Budhwar, Roli

2013-07-01

60

The Effect of Y-zeolite Acidity on m-Xylene Transformation Reactions S. Al-Khattaf*  

E-print Network

The Effect of Y-zeolite Acidity on m-Xylene Transformation Reactions S. Al-Khattaf* , A. Iliyas, A-Y and a series of dealuminated Y zeolite catalysts. The conversion of m-xylene was found to increase initially of zeolite acidity. A higher coke deposition was found for the transformation of m-xylene over the parent H

Al-Khattaf, Sulaiman

61

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

NASA Astrophysics Data System (ADS)

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

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

62

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

NASA Astrophysics Data System (ADS)

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

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

2015-04-01

63

Transposon-5 mutagenesis transforms Corynebacterium matruchotii to synthesize novel hybrid fatty acids that functionally replace corynomycolic acid.  

PubMed

Enzymes within the biosynthetic pathway of mycolic acid (C(60)-C(90) a-alkyl,b-hydroxyl fatty acid) in Mycobacterium tuberculosis are attractive targets for developing new anti-tuberculosis drugs. We have turned to the simple model system of Corynebacterium matruchotii to study the terminal steps in the anabolic pathway of a C32 mycolic acid called corynomycolic acid. By transposon-5 mutagenesis, we transformed C. matruchotii into a mutant that is unable to synthesize corynomycolic acid. Instead, it synthesized two related series of novel fatty acids that were released by saponification from the cell wall fraction and from two chloroform/methanol-extractable glycolipids presumed to be analogues of trehalose mono- and di-corynomycolate. By chemical analyses and MS, we determined the general structure of the two series to be 2,4,6,8,10-penta-alkyl decanoic acid for the larger series (C(70)-C(77)) and 2,4,6,8-tetra-alkyl octanoic acid for the smaller series (C(52)-C(64)), both containing multiple keto groups, hydroxy groups and double bonds. The mutant was temperature-sensitive, aggregated extensively, grew very slowly relative to the wild type, and was resistant to the presence of lysozyme. We suggest that a regulatory protein that normally prevents the transfer of the condensation product back to b-ketoacyl synthase in the corynomycolate synthase system of the wild type was inactivated in the mutant. This will result in multiple Claisen-type condensation and the formation of two similar series of these complex hybrid fatty acids. A similar protein in M. tuberculosis would be an attractive target for new drug discovery. PMID:12879902

Takayama, Kuni; Hayes, Barry; Vestling, Matha M; Massey, Randall J

2003-07-15

64

Approximation of orbital elements of telluric planets by compact analytical series  

NASA Astrophysics Data System (ADS)

We take the long-term numerical ephemeris of the major planets DE424 (Folkner 2011) and approximate the orbital elements of the telluric planets from that ephemeris by trigonometric series. Amplitudes of the series' terms are the second- or third-degree polynomials of time, and arguments are the fourth-degree time polynomials. The resulting series are precise and compact; in particular the maximum deviation of the planetary mean longitude calculated by the analytical series from that given by DE-424 over [-3000; 3000].

Kudryavtsev, S.

2014-12-01

65

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

E-print Network

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...

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

2015-01-01

66

[Essential fatty acids and their transformations in the animals (author's transl)].  

PubMed

The research of essential fatty acids biochemistry in Argentina was initiated approximately twenty years ago. These investigations together with the outstanding findings obtained in other countries proved the existence of different types of reactions. The essential fatty acids, linolenic and alpha linolenic, are converted by desaturation and elongation reactions in higher homologs building families of fatty acids. These reactions are regulated by dietary components, hormones, temperature and products of reaction. Retroconversion reactions transform the higher homologs, especially of 22 carbons back again to lower homologs avoiding beta oxidation. They are incorporated in the lipids to build the lipoproteic membranes increasing their fluidity. Specific acids are converted to prostaglandins that function as specific hormones. PMID:1052606

Brenner, R R

1976-01-01

67

Microbial transformation of 18beta-glycyrrhetinic acid by Cunninghamella elegans and Fusarium lini, and lipoxygenase inhibitory activity of transformed products.  

PubMed

The microbial transformation of 18beta-glycyrrhetinic acid (1) by Cunninghamella elegans afforded a metabolite, 3beta,7beta-dihydroxy-11-oxo-olean-12-en-30-oic acid (2), while fermentation of 1 with Fusarium lini afforded a metabolite, 3,11-dioxo-olean-12-en-30-oic acid (3). Compound 3 exhibited a potent lipoxygenase (LOX) inhibitory activity. The structures of these metabolites were elucidated on the basis of spectroscopic techniques. PMID:19384727

Iqbal Choudhary, Muhammad; Ali Siddiqui, Zafar; Ahmed Nawaz, Sarfraz

2009-01-01

68

Determination of glycolic acid in cosmetics by online liquid chromatography–Fourier transform infrared spectrometry  

Microsoft Academic Search

An isocratic online liquid chromatography Fourier transform infrared procedure has been developed for the determination of\\u000a glycolic acid in cosmetics. The method involves the ultrasound-assisted extraction of glycolic acid from the samples with\\u000a an acetonitrile:phosphate buffer (25 mM, pH 2.7) (3:97 v\\/v). The extracts were centrifuged and filtered before their injection\\u000a into the chromatography system, which was equipped with a C18

J. Kuligowski; A. Breivogel; G. Quintás; S. Garrigues; M. de la Guardia

2008-01-01

69

Synthesis of dihydroperoxides of linoleic and linolenic acids and studies on their transformation to 4-hydroperoxynonenal  

Microsoft Academic Search

The cytotoxic aldehydes 4-hydroxynonenal, 4-hydroperoxynonenal (4-HPNE), and 4-oxononenal are formed during lipid peroxidation\\u000a via oxidative transformation of the hydroxy or hydroperoxy precursor fatty acids, respectively. The mechanism of the carbon chain\\u000a cleavage reaction leading to the aldehyde fragments is not known, but Hock-cleavage of a suitable dihydroperoxide derivative\\u000a was implicated to account for the fragmentation [Schneider, C., Tallman, K.A., Porter,

Claus Schneider; William E. Boeglin; Huiyong Yin; Donald F. Stec; David L. Hachey; Ned A. Porter; Alan R. Brash

2005-01-01

70

TRANSFORMATION  

SciTech Connect

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

LACKS,S.A.

2003-10-09

71

Oleanolic acid inhibits proliferation and invasiveness of Kras-transformed cells via autophagy.  

PubMed

Oleanolic acid (OA) has been widely studied because of its pleiotropic therapeutic and preventive effect on various diseases. However, the mechanisms of OA's action are still not clear yet, especially its suppressing effect on transformed cells. In this work, we found that OA induced autophagy in normal tissue-derived cells without cytotoxicity. OA-induced autophagy was shown to decrease the proliferation of KRAS-transformed normal cells and to impair their invasion and anchorage-independent growth. Interrupting autophagy rescued OA's effect on the transformed cells. Mouse model experiments also demonstrated that OA suppressed the growth of KRAS-transformed breast epithelial cell MCF10A-derived tumor xenograft by inducing autophagy. Finally, we identified that OA induced autophagy in normal cells by inhibiting the activation of Akt/mTOR/S6K signaling. In conclusions, we found that OA treatment permitted normal cells to undergo autophagy. The induced autophagy was required for OA to prevent or delay the growth of transformed normal cells. PMID:25172632

Liu, Jia; Zheng, Lanhong; Ma, Leina; Wang, Bin; Zhao, Youguang; Wu, Ning; Liu, Ge; Lin, Xiukun

2014-11-01

72

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

NASA Astrophysics Data System (ADS)

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

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

2014-10-01

73

Effects of Fe oxide on N transformations in subtropical acid soils  

PubMed Central

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

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

2015-01-01

74

Effects of Fe oxide on N transformations in subtropical acid soils  

NASA Astrophysics Data System (ADS)

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

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

2015-02-01

75

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

PubMed

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

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

2015-01-01

76

Transformation of smectite to kaolinite in naturally acid soil systems: structural and thermodynamic considerations  

SciTech Connect

Four acid montmorillonitic soil profiles were sampled to study thermodynamic-stability relationships and chemical weathering of soil minerals. Solid- and solution-phase characterization indicated smectite to be the metastable precursor of kaolinite with the highest rate of transformation occurring in topsoil horizons. Structures of Al-saturated smectites were found to be nonideal with respect to excess structural OH/sup -/ water and below normal (approx. = 550/sup 0/C) dehydroxylation temperatures. Structural and thermochemical data suggested the weathering sequence was montmorillonite ..-->.. beidellite ..-->.. kaolinite. The smectite ..-->.. kaolinite transformation appears to be a combination of dissolution-precipitation and structural reorganization processes. Excess structural OH/sup -/ in the beidellitic structure seems to have played a key role in the transformations. Montmorillonite ..-->.. beidellite and beidellite ..-->.. kaolinite transformations were favored in the more weathered topsoil horizons where solutions were undersaturated with respect to amorphous SiO/sub 2/. Kaolinite precipitating from supersaturated solutions appeared to have a range in crystallinity and standard free energy of formation (..delta..G/sup 0//sub f/), approaching those of halloysite at high solution silica activities. 34 references, 5 figures, 7 tables.

Karathanasis, A.D.; Hajek, B.F.

1983-01-01

77

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

SciTech Connect

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.

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

2011-01-25

78

Complexation of chitosan with acetic acid according to Fourier transform Raman spectroscopy data  

NASA Astrophysics Data System (ADS)

The results of the interaction between the protonated chitosan (CHI) macromolecule and the acetate ion in dilute acetic acid solutions were studied by Fourier transform Raman spectroscopy and quantum-chemical modeling. The complexation of CHI with the acetate ion showed itself as the 934 cm-1 band in the Raman spectrum, which suggests the formation of [CHI+ · CH3COO-] type ion pairs. It was concluded that a comparative analysis of the integrated intensities of the Raman bands in the range 880-940 cm-1 makes it possible to judge about the relative content of hydrated acetate ions, CHI macromolecules of the [CHI+ · CH3COO-] complex, and acetic acid molecules not involved in CHI protonation.

Mikhailov, G. P.; Tuchkov, S. V.; Lazarev, V. V.; Kulish, E. I.

2014-06-01

79

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

NASA Astrophysics Data System (ADS)

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.

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

2015-01-01

80

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

NASA Astrophysics Data System (ADS)

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.

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

2014-06-01

81

Modifying fatty acid profiles through a new cytokinin-based plastid transformation system.  

PubMed

The widespread use of herbicides and antibiotics for selection of transgenic plants has not been very successful with regard to commercialization and public acceptance. Hence, alternative selection systems are required. In this study, we describe the use of ipt, the bacterial gene encoding the enzyme isopentenyl transferase from Agrobacterium tumefaciens, as a positive selectable marker for plastid transformation. A comparison between the traditional spectinomycin-based aadA selection system and the ipt selection system demonstrated that selection of transplastomic plants on medium lacking cytokinin was as effective as selection on medium containing spectinomycin. Proof of principle was demonstrated by transformation of the kasIII gene encoding 3-ketoacyl acyl carrier protein synthase III into tobacco plastids. Transplastomic tobacco plants were readily obtained using the ipt selection system, and were phenotypically normal despite over-expression of isopentenyl transferase. Over-expression of KASIII resulted in a significant increase in 16:0 fatty acid levels, and a significant decrease in the levels of 18:0 and 18:1 fatty acids. Our study demonstrates use of a novel positive plastid transformation system that may be used for selection of transplastomic plants without affecting the expression of transgenes within the integrated vector cassette or the resulting activity of the encoded protein. This system has the potential to be applied to monocots, which are typically not amenable to traditional antibiotic-based selection systems, and may be used in combination with a negative selectable marker as part of a two-step selection system to obtain homoplasmic plant lines. PMID:25280363

Dunne, Aisling; Maple-Grødem, Jodi; Gargano, Daniela; Haslam, Richard P; Napier, Johnathan A; Chua, Nam-Hai; Russell, Rosalind; Møller, Simon Geir

2014-12-01

82

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

PubMed Central

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

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

2014-01-01

83

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

PubMed Central

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

He, Liyan; Han, Xiaotian; Yu, Zhiming

2014-01-01

84

Reductive transformation of 2,4-dichlorophenoxyacetic acid by nanoscale and microscale Fe3O4 particles  

Microsoft Academic Search

Reductive transformation of 2,4-dichlorophenoxyacetic acid (2,4-D) by nanoscale and microscale Fe3O4 was investigated and compared. Disappearance of the parent species and formation of reaction intermediates and products were kinetically analyzed. Results suggest that the transformation of 2,4-D followed a primary pathway of its complete reduction to phenol and a secondary pathway of sequential reductive hydrogenolysis to 2,4-dichlorophenol (2,4-DCP), chlorophenol (2-CP,

You B. Si; Guo D. Fang; Jing Zhou; Dong M. Zhou

2010-01-01

85

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

NASA Astrophysics Data System (ADS)

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

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

1989-12-01

86

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

SciTech Connect

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.

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

87

Electrospray ionization fourier transform ion cyclotron resonance mass spectrometry of human alpha-1-acid glycoprotein.  

PubMed

The ultrahigh resolution and sensitivity of electrospray ionization Fourier transform ion cyclotron resonance (ESI-FTICR) mass spectrometry have for the first time been exploited for the characterization of highly sialylated glycoproteins, using human alpha-1-acid glycoprotein as the model compound. An alternative approach to the widely used high-performance liquid chromatography (HPLC) and matrix-assisted laser desorption/ionization (MALDI) assays is described. This new method does not require any enzymatic or chemical digestion (removal of sialyl groups or deglycosylation), chemical derivatization (introduction of chromophore groups), or preliminary chromatographic separation (HPLC or electrophoresis). Following ESI and accumulation of ions in a hexapole ion guide, ions are injected into the ICR cell. A selected mass window from the overall ion population is isolated and axialized prior to detection. After acquisition and Fourier transform of the transient signal the resulted spectrum is evaluated in order to determine the charge state of the detected ions and the isotope pattern of the measured protein glycoform. The presence of ions from the same glycoform with different charge states was confirmed. The advantages and limitations of the technique are discussed. Future prospects and possible applications are indicated. PMID:15373434

Nagy, Kornél; Vékey, Károly; Imre, Tímea; Ludányi, Krisztina; Barrow, Mark P; Derrick, Peter J

2004-09-01

88

Caffeic acid phenethyl ester (CAPE) prevents transformation of human cells by arsenite (As) and suppresses growth of As-transformed cells  

Microsoft Academic Search

Recent evidence suggests that inflammatory cytokines and growth factors contribute to arsenite (As)-induced human carcinogenesis. We investigated the expression of inflammatory cytokine mRNAs during the transformation process induced by chronic As exposure in non-tumorigenic human osteogenic sarcoma (N-HOS) cells using gene arrays, and results were confirmed by RT-PCR and protein arrays. Caffeic acid phenethyl ester (CAPE), a naturally occurring immunomodulating

Chengfeng Yang; Jing Wu; Ronghe Zhang; Ping Zhang; Jonathan Eckard; Rita Yusuf; Xi Huang; Toby G. Rossman; Krystyna Frenkel

2005-01-01

89

Transformation of leucine and rifampin traits in Neisseria gonorrhoeae with deoxyribonucleic acid from homologous and heterologous origins.  

PubMed

A leucine-requiring, rifampin-sensitive strain of Neisseria gonorrhoeae was transformed to a leucine-nonrequiring, rifampin-resistant phenotype with deoxyribonucleic acid (DNA) obtained from both N. meningitidis and N. gonorrhoeae. The transforming efficiency of the meningococcal DNA was about 10- to 100-fold less than that of the homologous gonococcal DNA. A chemically defined medium that would support growth of most gonococcal isolates was used as a complete medium. A minimal medium was used for selection of Leu+ transformants. N-methyl-N'-nitro-N-nitrosoguanidine was used as a mutagen for isolating leucine prototrophs from leucine-requiring isolates of N. gonorrohoeae. PMID:803480

Wood, D O; Brownell, G H

1975-02-01

90

Specific effects of heating of transformable streptococci on their ability to discriminate between homospecific, heterospecific, and hybrid deoxyribonucleic acid.  

PubMed

Heating competent bacteria of the Challis strain of Streptococcus at a temperature of 48 C causes them to lose their transformability and mainfest a slight retardation of growth rate without loss of viability. The heat-induced loss of transformability is due to diminution in the ability of the bacteria to bind deoxyribonucleic acid (DNA) irreversibly. Another effect of heat is upon a step in the transformation process subsequent to binding, a step in which DNA molecules will compete if they multiply infect an unheated cell. Despite the reduction in irreversible binding exhibited by heated cells, competition between DNA molecules to transform these cells is decreased. Neither of these sites affected by heat exhibits any specificity with regard to origin of DNA. Since heat treatment causes a relative stimulation of transformation by heterospecific DNA, a third effect of heat must be envisaged. The amount of heat-induced stimulation is dependent upon the amount of heterospecific material in the transforming DNA. Linkage of heterospecific markers is increased as a consequence of heating the recipients. Transformation by markers of different transforming efficiency in homospecific DNA is also affected by heat treatment in a differential manner. Taken together, these results point to a heat-sensitive intracellular mechanism that recognizes DNA base sequences during transformation. The effect of heat upon discrimination against heterospecific DNA has been found to occur also in the pneumococcus and in Bacillus subtilis. PMID:4621682

Ravin, A W; Ma, M

1972-02-01

91

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

PubMed

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

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

2014-08-01

92

Role of Na+ in alpha -aminoisobutyric Acid Uptake by Membrane Vesicles from Mouse Fibroblasts Transformed by Simian Virus 40  

Microsoft Academic Search

The uptake of alpha -amino[3H]isobutyric acid (AIB) was studied in membrane vesicles from mouse fibroblasts transformed by simian virus 40 to examine the features of the Na+-stimulated and Na+-dependent AIB transport process. The simultaneous addition of NaCl and AIB to these vesicles produced a transient accumulation, or ``overshoot,'' of amino acid 3-4 times the equilibrium value. Both the initial rate

Hoyoku Nishino; Robert M. Schiller; Jane R. Parnes; Kurt J. Isselbacher

1978-01-01

93

Determination by fourier transform Raman spectroscopy of conjugated linoleic acid in I2-photoisomerized soybean oil.  

PubMed

The potential of Fourier transform (FT)-Raman spectroscopy to quantify the total conjugated linoleic acid (CLA) content was evaluated to find a technique for the routine control of CLA synthesis by chemical procedures. The calibration and validation samples were obtained by photoisomerization of linoleic acid contained in soybean oil. The catalyst was iodine (I(2)), and the light source was the green line (514.5 nm) of an argon ion laser. The criteria to select the best partial least-squares (PLS) calibration model were a low standard error of prediction (SEP), a high correlation coefficient (R), and the selection of relevant variables of the Raman spectrum to reduce spectral interferences. The total CLA content of the 22 samples ranged from 0.05 to 3.28% of total lipids. The best PLS calibration model was obtained with three optimal factors, a SEP of 0.22, and a R of 0.97. This calibration model was obtained after baseline correction of the CC stretching region (1642-1680 cm(-1)), which contained sufficient spectral information for reliable CLA quantification. PMID:19588975

Bernuy, Bruno; Meurens, Marc; Mignolet, Eric; Turu, Christine; Larondelle, Yvan

2009-08-12

94

Structure-function evolution of the Transforming acidic coiled coil genes revealed by analysis of phylogenetically diverse organisms  

Microsoft Academic Search

BACKGROUND: Examination of ancient gene families can provide an insight into how the evolution of gene structure can relate to function. Functional homologs of the evolutionarily conserved transforming acidic coiled coil (TACC) gene family are present in organisms from yeast to man. However, correlations between functional interactions and the evolution of these proteins have yet to be determined. RESULTS: We

Ivan H Still; Ananthalakshmy K Vettaikkorumakankauv; Anthony DiMatteo; Ping Liang

2004-01-01

95

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

NASA Astrophysics Data System (ADS)

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

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

2013-12-01

96

Chemistry of fog waters in California's Central Valley: 2. Photochemical transformations of amino acids and alkyl amines  

NASA Astrophysics Data System (ADS)

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 or monochromatic light. In all experiments four amino acids - histidine (His), methionine (Met), tryptophan (Trp), and tyrosine (Tyr) - consistently decayed, with half-lives that ranged from ˜1 h (Met) to ˜23 h (Tyr) in midday, winter-solstice sunlight at Davis, CA ( solar zenith angle =62°) . Half-lives for the remaining amino compounds examined were typically >45 h in our experiments. Reactions with photoformed hydroxyl radical ( ·OH) and singlet molecular oxygen (O 2( 1? g) or 1O2?) accounted for essentially all of the loss of His and Tyr, the less reactive of the four amino acids that consistently decayed, but were minor sinks for the more reactive compounds (Met and Trp). Additional experiments revealed that methionine sulfoxide (MetSO) was formed with a yield of 58-88% during the oxidation of methionine, suggesting that the ratio of MetSO to Met might be a useful chemical marker for the age of atmospheric particles and drops. Other products expected from the transformation of amino compounds include ammonia, organic acids, and possibly mutagenic nitrosoaromatics. To complement our laboratory experiments, we also calculated rates of transformations of amino acids in near-neutral pH fog drops under ambient conditions. These calculations reveal that ozone should be a major sink for amino acids and that half-lives for many amino acids in ambient fog drops will be much shorter than those determined in our photochemistry experiments. Overall, our results indicate that reactions in atmospheric condensed phases will transform amino nitrogen compounds (including free amino acids as well as proteins and peptides) and, consequently, increase the bioavailability of nitrogen in atmospheric deposition.

McGregor, Keith G.; Anastasio, Cort

97

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

SciTech Connect

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.

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

98

Alpha lipoic acid selectively inhibits proliferation and adhesion to fibronectin of v-H-ras-transformed 3Y1 cells.  

PubMed

Here, we focused on the effects of racemic ?-lipoic acid on proliferation and adhesion properties of 3Y1 rat fibroblasts and the v-H-ras-transformed derivative, HR-3Y1-2 cells. Racemic ?-lipoic acid inhibited proliferation of HR-3Y1-2 but not 3Y1 cells at 0.3 and 1.0 mM. R-(+)-?-lipoic acid also inhibited proliferation of HR-3Y1-2 cells equivalent to that of racemic ?-lipoic acid. In addition, racemic ?-lipoic acid decreased intracellular reactive oxygen species levels in HR-3Y1 cells but not 3Y1 cells. Next, we evaluated the effects of racemic ?-lipoic acid on cell adhesion to fibronectin. The results indicated that racemic ?-lipoic acid decreased adhesive ability of HR-3Y1-2 cells to fibronectin-coated plates. As blocking antibody experiment revealed that ?1-integrin plays a key role in cell adhesion in this experimental system, the effects of racemic ?-lipoic acid on the expression of ?1-integrin were examined. The results indicated that racemic ?-lipoic acid selectively downregulated the expression of cell surface ?1-integrin expression in HR-3Y1-2 cells. Intriguingly, exogenous hydrogen peroxide upregulated cell surface ?1-integrin expression in 3Y1 cells. Taken together, these data suggest that reduction of intracellular reactive oxygen species levels by ?-lipoic acid could be an effective means of ameliorating abnormal growth and adhesive properties in v-H-ras transformed cells. PMID:22573927

Yamasaki, Masao; Iwase, Masahiro; Kawano, Kazuo; Sakakibara, Yoichi; Suiko, Masahito; Nishiyama, Kazuo

2012-05-01

99

Effect of a sulfonated azo dye and sulfanilic acid on nitrogen transformation processes in soil.  

PubMed

Introduction of organic dyes into soil via wastewater and sludge applications has been of increasing concern especially in developing or under-developed countries where appropriate management strategies are scarce. Assessing the response of terrestrial ecosystems to organic dyes and estimating the inhibition concentrations will probably contribute to soil remediation studies in regions affected by the same problem. Hence, an incubation study was conducted in order to investigate the impact of a sulfonated azo dye, Reactive Black 5 (RB5) and sulfanilic acid (SA), a typical representative of aromatic sulfonated amines, on soil nitrogen transformation processes. The results apparently showed that nitrogen related processes in soil can be used as bioindicators of anthropogenic stress caused by organic dyes. It was found that urease activity, arginine ammonification rate, nitrification potential and ammonium oxidising bacteria numbers decreased by 10-20% and 7-28% in the presence of RB5 (> 20 mg/kg dry soil) and SA (> 8 mg/kg dry soil), respectively. Accordingly, it was concluded that organic dye pollution may restrict the nitrogen-use-efficiency of plants, thus further reducing the productivity of terrestrial ecosystems. Furthermore, the response of soil microbiota to SA suggested that inhibition effects of the organic dye may continue after the possible reduction of the parent dye to associated aromatic amines. PMID:19524359

Topaç, F Olcay; Dindar, Efsun; Uçaro?lu, Selnur; Ba?kaya, Hüseyin S

2009-10-30

100

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

PubMed

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

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

101

[Effect of low molecular weight organic acids on inorganic phosphorus transformation in red soil and its acidity].  

PubMed

Red soil samples collected from southern Hubei province and northern Jiangxi province were tested to analyze their inorganic phosphorus fractions, pH and active aluminum after incubated with added various organic acids. The results indicated that application of organic acids increased the content of Ca2-P in both red soils, in the order of citric acid > malic acid > succinic acid > acetic acid, did not affect the contents of Ca8-P and Ca10-P, but usually reduced Fe-P, Al-P and O-P. The pH values of the soils treated by organic acids, except for acetic acid, were reduced by 0.65-1.96, compared with the control. Soil active Al extracted with 0.02 mol.L-1 CaCl2 in treatments with citric, malic and succinic acid was 5.7-51.3 times as the control, and Al extracted with 1 mol.L-1 KCl also increased 4.0-67.3 times. However, acetic acid had little influence on active soil Al. It was concluded that in red soils, organic acid could improve phosphorus availability, but enhance the soil toxicity caused by active Al. PMID:12385221

Hu, Hongqing; Liao, Lixia; Wang, Xinglin

2002-07-01

102

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

NASA Astrophysics Data System (ADS)

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.

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

2004-10-01

103

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

Microsoft Academic Search

Oxalic acid is often the leading contributor to the total dicarboxylic acid mass in ambient organic aerosol particles. During the 2004 International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) field campaign, nine inorganic ions (including SO42?) and five organic acid ions (including oxalate) were measured on board the Center for Interdisciplinary Remotely Piloted Aircraft Studies (CIRPAS) Twin Otter

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

2006-01-01

104

An empirical model of amino acid transformations in an alpine soil D.A. Lipson*, T.K. Raab, S.K. Schmidt, R.K. Monson  

E-print Network

An empirical model of amino acid transformations in an alpine soil D.A. Lipson*, T.K. Raab, S; accepted 22 June 2000 Abstract Amino acids are potentially important nitrogen (N) sources for plants ecosystems. This study estimates seasonal amino acid ¯uxes in an alpine tundra soil using three independent

Schmidt, Steven K.

105

Diazotization of 6-amino-2-phenyl-7-chloro-2 H -benzotriazole-4-carboxylic acid and transformations of the resulting diazo compounds  

Microsoft Academic Search

6-Amino-2-phenyl-7-chloro-2H-benzotriazole-4-carboxylic acid was prepared by oxidation of 2,5-diamino-4-chloro-2-phenylazobenzoic acid, and its diazotization and subsequent transformations of the diazo compounds were studied. 7-Hydroxy-2-phenyl-2H-benzotriazole-4-carboxylic acid was prepared.

G. L. Artamonov; V. P. Perevalov

2004-01-01

106

Gene expression of the lysophosphatidic acid receptor 1 is a target of transforming growth factor beta.  

PubMed

The lysophosphatidic acid (LPA) receptor LPA1/Edg2 is the first identified LPA receptor. Although its wide tissue distribution and biological functions have been well studied, little is known about how LPA1 is transcriptionally regulated. In the current study, we showed that LPA1 is a physiological target of transforming growth factor beta (TGF?)-mediated repression. In both normal and neoplastic cells, TGF? inhibits LPA1 promoter activity, LPA1 mRNA expression and LPA1-dependent chemotaxis and tumor cell invasion. Knockdown of the TGF? intracellular effector Smad3 or Smad4 with lentivirally transduced short hairpin RNA relieved these inhibitory effects of TGF?. Interestingly, the LPA1 promoter contains two potential TGF? inhibitory elements (TIEs), each consisting of a Smad-binding site and an adjacent E2F4/5 element, structurally similar to the TIE found on the promoter of the well-defined TGF? target gene c-myc. Deletion and point mutation analyses indicate that the distal TIE located at 401?bp from the transcription initiation site, is required for TGF? repression of the LPA1 promoter. A DNA pull-down assay showed that the -401 TIE was capable of binding Samd3 and E2F4 in TGF?-treated cells. TGF?-induced binding of the Smad complex to the native -401 TIE sequence of the LPA1 gene promoter was further verified by chromatin immunoprecipitation assays. We therefore identified a novel role of TGF? in the control of LPA1 expression and LPA1-coupled biological functions, adding LPA1 to the list of TGF?-repressed target genes. PMID:22824789

Wu, J; Mukherjee, A; Lebman, D A; Fang, X

2013-06-27

107

Microbial transformation of acetyl-11-keto-?-boswellic acid and their inhibitory activity on LPS-induced NO production.  

PubMed

The capabilities of 20 strains of fungi to transform acetyl-11-keto-?-boswellic (AKBA) were screened. And biotransformation of AKBA by Cunninghamella blakesleana AS 3.970 afforded five metabolites (1-5), while two metabolites (6, 7) were isolated from biotransformation of Cunninghamella elegans AS 3.1207. The chemical structures of these metabolites were identified by spectral methods including 2D NMR and their structures were elucidated as 7?-hydroxy-3-acety-11-keto-?-boswellic acid (1), 21?-dihydroxy-3-acety-11-keto-?-boswellic acid (2), 7?,22?-dihydroxy-3-acety-11-keto-?-boswellic acid (3), 7?,16?-dihydroxy-3-acety-11-keto-?-boswellic acid (4), 7?,15?-dihydroxy-3-acety-11-keto-?-boswellic acid (5); 7?,15?,21?-trihydroxy-3-acety-11-keto-?-boswellic acid (6) and 15?,21?-dihydroxy-3-acety-11-keto-?-boswellic acid (7). All these products are previously unknown. Their primary structure-activity relationships (SAR) of inhibition activity on LPS-induced NO production in RAW 264.7 macrophage cells were evaluated. PMID:23391590

Sun, Yan; Liu, Dan; Xi, Ronggang; Wang, Xiaobo; Wang, Yan; Hou, Jie; Zhang, Baojing; Wang, Changyuan; Liu, Kexin; Ma, Xiaochi

2013-03-01

108

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

SciTech Connect

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

Foo, Choo Thye [Malaysian Nuclear Agency (Nuclear Malaysia) Bangi, Selangor (Malaysia); Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology, University Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Mahmood, Che Seman [Malaysian Nuclear Agency (Nuclear Malaysia) Bangi, Selangor (Malaysia); Mohd Salleh, Mohamad Amran, E-mail: asalleh@eng.upm.edu.my [Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology, University Putra Malaysia, 43400 Serdang, Selangor (Malaysia); Chemical Engineering Department, University Putra Malaysia, 43400 Serdang, Selangor (Malaysia)

2011-04-15

109

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

NASA Astrophysics Data System (ADS)

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.

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

2015-03-01

110

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

PubMed

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

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

2015-01-01

111

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

PubMed Central

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

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

2015-01-01

112

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

PubMed

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

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

2014-08-17

113

Physical size of the donor locus and transmission of Haemophilus influenzae ampicillin resistance genes by deoxyribonucleic acid-mediated transformation.  

PubMed Central

The properties of donor deoxyribonucleic acid (DNA) from three clinical isolates and its ability to mediate the transformation of competent Rd strains to ampicillin resistance were examined. A quantitative technique for determining the resistance of individual Haemophilus influenzae cells to ampicillin was developed. When this technique was used, sensitive cells failed to tolerate levels of ampicillin greater than 0.1 to 0.2 mug/ml, whereas three resistant type b beta-lactamase-producing strains could form from the colonies in 1- to 3-mug/ml levels of the antibiotic. DNA extracted from the resistant strains elicited transformation of the auxotrophic genes in a multiply auxotrophic Rd strain. For two of the donors, transformation to ampicillin resistance occurred after the uptake of a single DNA molecule approximately 104-fold less frequently than transformation of auxotrophic loci and was not observed to occur at all with the third. The frequency of transformation to ampicillin resistance was two- to fivefold higher in strain BC200 (Okinaka and Barnhart, 1974), which was cured of a defective prophage. All three clinical ampicillin-resistant strains were poor recipients, but the presence of the ampicillin resistant genes in strain BC200 did not reduce its competence. Sucrose gradients of DNA from ampicillin-resistant transformants of BC200 and from the original ampicillin-resistant strains showed that: (i) all the DNA preparations had high molecular weights; (ii) donor activity for ampicillin resistance sedimented heterogeneously and in parallel with genome DNA up to the highest molecular weights observed (100 x 106 to 200 x 106); and (iii) genetic transformation of ampicillin resistance from strain BC200-amp90383 required the physical integrity of a linearly integrated segment of DNA having a molecular weight of about 25 x 106 to 30 x 106. PMID:1081986

Bendler, J W

1976-01-01

114

Generation of organic acids and monosaccharides by hydrolytic and oxidative transformation of food processing residues.  

PubMed

Carbohydrate-rich biomass residues, i.e. sugar beet molasses, whey powder, wine yeast, potato peel sludge, spent hops, malt dust and apple marc, were tested as starting materials for the generation of marketable chemicals, e.g. aliphatic acids, sugar acids and mono-/disaccharides. Residues were oxidized or hydrolyzed under acidic or alkaline conditions applying conventional laboratory digestion methods and microwave assisted techniques. Yields and compositions of the oxidation products differed according to the oxidizing agent used. Main products of oxidation by 30% HNO(3) were acetic, glucaric, oxalic and glycolic acids. Applying H(2)O(2)/CuO in alkaline solution, the organic acid yields were remarkably lower with formic, acetic and threonic acids as main products. Gluconic acid was formed instead of glucaric acid throughout. Reaction of a 10% H(2)O(2) solution with sugar beet molasses generated formic and lactic acids mainly. Na(2)S(2)O(8) solutions were very inefficient at oxidizing the residues. Glucose, arabinose and galactose were formed during acidic hydrolysis of malt dust and apple marc. The glucose content reached 0.35 g per gram of residue. Important advantages of the microwave application were lower reaction times and reduced reagent demands. PMID:15607197

Fischer, Klaus; Bipp, Hans-Peter

2005-05-01

115

Differential Modulation of Transforming Growth Factor-?1 Expression and Mucin Deposition by Retinoic Acid and Sodium Lauryl Sulfate in Human Skin  

Microsoft Academic Search

Immunohistochemical staining of skin sections with two polyclonal antibodies (anti-CC 1-30 and anti-LC 1-30), specific for transforming growth factor-?1, revealed increased extracellular and decreased intracellular expression of transforming growth factor-?1in retinoic acid-treated, compared to vehicle-treated, skin. Transforming growth factor-?1staining, with both antibodies, was most marked in the upper layers of the epidermis, although dermal staining was also evident. The modulation

Gary J. Fisher; Amir Tavakkol; Christopher E. M. Griffiths; James T. Elder; Qing-Yu Zhang; Lawrence Finkel; David Danielpour; Adam B. Glick; Howard Higley; Larry Ellingsworth; John J. Voorhees

1992-01-01

116

Transforming Growth Factor b2 Promotes Glucose Carbon Incorporation into Nucleic Acid Ribose through the Nonoxidative Pentose Cycle in Lung Epithelial Carcinoma Cells1  

Microsoft Academic Search

The invasive transformation of A-459 lung epithelial carcinoma cells has been linked to the autocrine regulation of malignant phenotypic changes by transforming growth factor b (TGF-b). Here we demonstrate, using stable 13C glucose isotopes, that the transformed phenotype is characterized by decreased CO2 production via direct glucose oxidation but increased nucleic acid ribose synthesis through the nonoxidative reactions of the

Laszlo G. Boros; John S. Torday; Shu Lim; Sara Bassilian; Marta Cascante; Wai-Nang Paul Lee

117

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

PubMed

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

Dawidowicz, Andrzej L; Typek, Rafal

2015-01-15

118

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

PubMed Central

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

Fakour, Hoda; Lin, Tsair-Fuh

2014-01-01

119

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

PubMed Central

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

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

1966-01-01

120

Absence de transformation bactrienne des acides biliaires chez la truite arc-en-ciel, Saimo gairdneri,  

E-print Network

Nivelle, 64310 Ascain. Summary. Absence of bacterial conversion of bile acids in the rainbow trout, Salmo gairdneri, raised at 16 °c. The fecal bile acids of the rainbow trout, Salmo gairdneri, raised at 16 o of a bacterial flora adapted to the digestive tract of that fish. Il n'existe qu'un nombre restreint d

Paris-Sud XI, Université de

121

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

Microsoft Academic Search

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

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

1999-01-01

122

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

SciTech Connect

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

Adamowicz, Ludwik

1996-04-30

123

Molecular cloning of equine transforming growth factor-beta1 reveals equine-specific amino acid substitutions in the mature peptide sequence  

Microsoft Academic Search

This study cloned and sequenced equine transform- ing growth factor (TGF)-1, yielding a unique nucleotide structure which predicted amino acid substitutions not seen in other mammalian species. The nucleotide sequence homology was 89% to bovine, 91% to man, 90% to ovine, and 86% to rat. Derived amino acid sequence comparison showed that the equine protein was unique, differing by two

A J Nixon; B D Brower-Toland; L J Sandell

2000-01-01

124

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

NASA Technical Reports Server (NTRS)

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.

Tolbert, Margaret A.; Middlebrook, Ann M.

1990-01-01

125

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

NASA Astrophysics Data System (ADS)

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.

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

2011-06-01

126

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

NASA Technical Reports Server (NTRS)

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.

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

1992-01-01

127

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

PubMed Central

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

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

1993-01-01

128

Growth and shape transformations of giant phospholipid vesicles upon interaction with an aqueous oleic acid suspension  

Microsoft Academic Search

The interaction of two types of vesicle systems was investigated: micrometer-sized, giant unilamellar vesicles (GUVs) formed from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and submicrometer-sized, large unilamellar vesicles (LUVs) formed from oleic acid and oleate, both in a buffered aqueous solution (pH 8.8). Individual POPC GUVs were transferred with a micropipette into a suspension of oleic acid\\/oleate LUVs, and the shape changes of the

Primoz Peterlin; Vesna Arrigler; Ksenija Kogej; Sasa Svetina; Peter Walde

2009-01-01

129

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

NASA Astrophysics Data System (ADS)

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.

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

2014-04-01

130

Transformation of ferulic acid to vanillin using a fed-batch solid-liquid two-phase partitioning bioreactor.  

PubMed

Amycolatopsis sp. ATCC 39116 (formerly Streptomyces setonii) has shown promising results in converting ferulic acid (trans-4-hydroxy-3-methoxycinnamic acid; substrate), which can be derived from natural plant wastes, to vanillin (4-hydroxy-3-methoxybenzaldehyde). After exploring the influence of adding vanillin at different times during the growth cycle on cell growth and transformation performance of this strain and demonstrating the inhibitory effect of vanillin, a solid-liquid two-phase partitioning bioreactor (TPPB) system was used as an in situ product removal technique to enhance transformation productivity by this strain. The thermoplastic polymer Hytrel(®) G4078W was found to have superior partitioning capacity for vanillin with a partition coefficient of 12 and a low affinity for the substrate. A 3-L working volume solid-liquid fed-batch TPPB mode, using 300 g Hytrel G4078W as the sequestering phase, produced a final vanillin concentration of 19.5 g/L. The overall productivity of this reactor system was 450 mg/L. h, among the highest reported in literature. Vanillin was easily and quantitatively recovered from the polymers mostly by single stage extraction into methanol or other organic solvents used in food industry, simultaneously regenerating polymer beads for reuse. A polymer-liquid two phase bioreactor was again confirmed to easily outperform single phase systems that feature inhibitory or easily further degraded substrates/products. This enhancement strategy might reasonably be expected in the production of other flavor and fragrance compounds obtained by biotransformations. PMID:24167066

Ma, Xiao-kui; Daugulis, Andrew J

2014-01-01

131

Concurrent Changes in Transducing Efficiency and Content of Transforming Deoxyribonucleic Acid in Bacillus subtilis Bacteriophage SP-10  

PubMed Central

Taylor, Martha J. (Fort Detrick, Frederick, Md.), and Curtis B. Thorne. Concurrent changes in transducing efficiency and content of transforming deoxyribonucleic acid in Bacillus subtilis bacteriophage SP-10. J. Bacteriol. 91:81–88. 1966.—Spores of Bacillus subtilis W-23-Sr infected with transducing phage SP-10 served as convenient inocula for broth cultures from which transducing phage was harvested. Methods are described for producing highly infected spores. The inoculum level of infected spores in nutrient broth-yeast extract-glucose medium affected the transducing efficiency of SP-10 in lysates of these cultures. Phage in lysates of cultures inoculated with about 105 or fewer spores per milliliter transduced 20- to 350-fold more efficiently than did phage in lysates from cultures inoculated with 106 to 107 spores per milliliter. Transduction frequencies in the order of 10?5 per plaque-forming unit were obtained routinely, and some infected-spore preparations yielded phage that gave frequencies as high as 10?4. The combination of inoculum level and incubation time required to produce the best transducing phage had to be determined empirically for each batch of infected spores. Several possible explanations for the difference between lysates having high (HTE) and those having low (LTE) transducing efficiency were ruled out by special experiments. The hypothesis is presented that some cultural condition resulting from a relatively low inoculum of phage-infected spores favors the incorporation by phage particles of bacterial deoxyribonucleic acid (DNA) in the manner required for the production of transducing phage. Support for this hypothesis is a demonstration, through transformation experiments with DNA extracted from HTE and LTE phage particles, that populations of HTE phage particles yielded significantly more (7 to 27 times) transforming activity per microgram of DNA than did populations of LTE phage. PMID:4955254

Taylor, Martha J.; Thorne, Curtis B.

1966-01-01

132

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

PubMed

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

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

133

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

PubMed

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

Dawidowicz, Andrzej L; Typek, Rafal

2014-11-12

134

Transformation of 1-Menthene by a Cladosporium: Accumulation of ?-Isopropyl Glutaric Acid in the Growth Medium  

PubMed Central

An organism isolated from soil samples collected near a terpene plant grew in the presence of 1-menthene, with no other major source of carbon and energy. The organism was tentatively identified as a member of the genus Cladosporium. When this organism was grown in the presence of 1-menthene, with no other major source of carbon, substantial quantities of ?-isopropyl glutaric acid accumulated in the fermentation medium. ?-Isopropyl glutaric acid is probably an end product of the degradation of 1-menthene by the organism. PMID:16349992

Mukherjee, Barid B.; Kraidman, Gary; Hill, Ira D.

1974-01-01

135

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

SciTech Connect

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.

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

136

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...

137

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 ...

138

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 ...

139

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

Microsoft Academic Search

Formation of the tetrapyrrole pigment precursor δ-aminolevulinic acid (ALA) from glutamate was detected and partially characterized in extracts of the strictly anaerobic green photosynthetic bacterial species Chlorobium vibrioforme by using assay methods derived from those developed for algae and cyanobacteria. ALA formation in Chlorobium extracts was saturated at 10 mM glutamate and required NADPH and ATP at optimal concentrations of

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

1989-01-01

140

Microbial Transformation of Nitriles to High-Value Acids or Amides  

NASA Astrophysics Data System (ADS)

Biotransformation of nitriles mediated by nitrile-amide converting enzymes has attracted considerable attention and developed tremendously in the recent years in China since it offers a valuable alternative to traditional chemical reaction which requires harsh conditions. As a result, an upsurge of these promising enzymes (including nitrile hydratase, nitrilase and amidase) has been taking place. This review aims at describing these enzymes in detail. A variety of microorganisms harboring nitrile-amide converting activities have been isolated and identified in China, some of which have already applied with moderate success. Currently, a wide range of high-value compounds such as aliphatic, alicyclic, aromatic and heterocyclic amides and their corresponding acids were provided by these nitrile-amide degra-ding organisms. Simultaneously, with the increasing demand of chiral substances, the enantioselectivity of the nitrilase superfamily is widely investigated and exploited in China, especially the bioconversion of optically active ?-substituted phenylacetamides, acids and 2,2-dimethylcyclopropanecarboxamide and 2,2-dimethylcyclopropanecarboxylic acid by means of the catalysts exhibiting excellent stereoselectivity. Besides their synthetic value, the nitrile-amide converting enzymes also play an important role in environmental protection. In this context, cloning of the genes and expression of these enzymes are presented. In the near future in China, an increasing number of novel nitrile-amide converting organisms will be screened and their potential in the synthesis of useful acids and amides will be further exploited.

Chen, Jing; Zheng, Ren-Chao; Zheng, Yu-Guo; Shen, Yin-Chu

141

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...

142

Vibrational spectroscopy of cis- and trans-formic acid in solid argon  

NASA Astrophysics Data System (ADS)

Absorption spectra of cis and trans conformers of formic acid (HCOOH) isolated in solid argon are analyzed in the mid-infrared (4000- 400 cm-1) and near-infrared (7800- 4000 cm-1) regions. The HCOOH absorption spectrum reveals matrix-site splitting for the trapped molecule. Narrowband tunable infrared radiation is used to pump a suitable vibrational transition of the trans conformer in order to promote site-selectively the conversion to the cis conformer and separate the spectral features of each site group. Several anharmonic resonances are identified for both conformers. The results of anharmonic vibrational ab initio calculations (CC-VSCF) for the trans and cis conformers of formic acid are reported and compared with the experimental spectra.

Maçôas, Ermelinda M. S.; Lundell, Jan; Pettersson, Mika; Khriachtchev, Leonid; Fausto, Rui; Räsänen, Markku

2003-05-01

143

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

PubMed

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

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

2015-04-01

144

Fourier Transform Vibrational Circular Dichroism Of Carbonyl Stretching Modes In N-urethanyl-a-amino acids  

NASA Astrophysics Data System (ADS)

The vibrational circular dichroism (VCD) spectra of the N-t-BOC and N-CBZ-derivatives of alanine, proline, phenylalanine and valine in 0.2M CHC13 solutions all exhibit a characteristic, strong bisignate couplet in the carbonyl stretching region. The VCD couplet is interpreted in terms of the coupled oscillation of the urethane and acid carbonyl groups in an intramolecularly hydrogen-bonded structure.

Chernovitz, Anita C.; Freedman, Teresa B.; Nafie, Laurence A.

1985-12-01

145

An Unusual Abscisic Acid and Gibberellic Acid Synergism Increases Somatic Embryogenesis, Facilitates Its Genetic Analysis and Improves Transformation in Medicago truncatula  

PubMed Central

Somatic embryogenesis (SE) can be readily induced in leaf explants of the Jemalong 2HA genotype of the model legume Medicago truncatula by auxin and cytokinin, but rarely in wild-type Jemalong. Gibberellic acid (GA), a hormone not included in the medium, appears to act in Arabidopsis as a repressor of the embryonic state such that low ABA (abscisic acid): GA ratios will inhibit SE. It was important to evaluate the GA effect in M. truncatula in order to formulate generic SE mechanisms, given the Arabidopsis information. It was surprising to find that low ABA:GA ratios in M. truncatula acted synergistically to stimulate SE. The unusual synergism between GA and ABA in inducing SE has utility in improving SE for regeneration and transformation in M. truncatula. Expression of genes previously shown to be important in M. truncatula SE was not increased. In investigating genes previously studied in GA investigations of Arabidopsis SE, there was increased expression of GA2ox and decreased expression of PICKLE, a negative regulator of SE in Arabidopsis. We suggest that in M. truncatula there are different ABA:GA ratios required for down-regulating the PICKLE gene, a repressor of the embryonic state. In M. truncatula it is a low ABA:GA ratio while in Arabidopsis it is a high ABA:GA ratio. In different species the expression of key genes is probably related to differences in how the hormone networks optimise their expression. PMID:24937316

Nolan, Kim E.; Song, Youhong; Liao, Siyang; Saeed, Nasir A.; Zhang, Xiyi; Rose, Ray J.

2014-01-01

146

Transformation-associated changes in sphingolipid metabolism sensitize cells to lysosomal cell death induced by inhibitors of acid sphingomyelinase.  

PubMed

Lysosomal membrane permeabilization and subsequent cell death may prove useful in cancer treatment, provided that cancer cell lysosomes can be specifically targeted. Here, we identify acid sphingomyelinase (ASM) inhibition as a selective means to destabilize cancer cell lysosomes. Lysosome-destabilizing experimental anticancer agent siramesine inhibits ASM by interfering with the binding of ASM to its essential lysosomal cofactor, bis(monoacylglycero)phosphate. Like siramesine, several clinically relevant ASM inhibitors trigger cancer-specific lysosomal cell death, reduce tumor growth in vivo, and revert multidrug resistance. Their cancer selectivity is associated with transformation-associated reduction in ASM expression and subsequent failure to maintain sphingomyelin hydrolysis during drug exposure. Taken together, these data identify ASM as an attractive target for cancer therapy. PMID:24029234

Petersen, Nikolaj H T; Olsen, Ole D; Groth-Pedersen, Line; Ellegaard, Anne-Marie; Bilgin, Mesut; Redmer, Susanne; Ostenfeld, Marie S; Ulanet, Danielle; Dovmark, Tobias H; Lønborg, Andreas; Vindeløv, Signe D; Hanahan, Douglas; Arenz, Christoph; Ejsing, Christer S; Kirkegaard, Thomas; Rohde, Mikkel; Nylandsted, Jesper; Jäättelä, Marja

2013-09-01

147

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

PubMed Central

Suberoylanilide hydroxamic acid (SAHA) inhibiting cancer cell growth has been associated with its down-regulation 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. PMID:22749963

Zhang, Jingjie; Ouyang, Weiming; Li, Jingxia; Zhang, Dongyun; Yu, Yonghui; Wang, York; Li, Xuejun; Huang, Chuanshu

2013-01-01

148

Transformations of anthraquinone-1-nitro-2-carboxylic acid during reduction by hydrogen on a catalyst  

SciTech Connect

We studied the catalytic reduction of anthraquinone-1-nitro-2-carboxylic acid by hydrogen under a pressure of 0.1-5.5 MPa and at temperatures of 20-100/sup 0/C in different solvents. The concentration of the substrate was varied from 0.05 to 0.3 mole/dm/sub 3/. A 5% palladium on carbon was used in a thermostated ideal mixing reactor. The process was controlled by the rate of absorption of hydrogen; polarographic, spectral and GLC methods of analysis were used to identify the compounds and to evaluate the quantitative composition of the products.

Rogovik, V.M.; Dzvinka, R.I.; Vinyukova, M.V.

1987-11-20

149

Identification of nematicidal fatty acids and triglycerides from seeds of Jubaea chilensis by GC-EI-MS and chemical transformation methods.  

PubMed

Nematicidal bioassay-guided fractionation of the n-hexane extract of the seeds of Jubaea chilensis led to the identification of eight known fatty acids and a mixture of triglycerides, reported for the first time for this species. In addition, their corresponding methyl esters were identified to be artifacts generated during the extraction and isolation procedures by using GC-EI-MS and chemical transformation methods. The fatty acid composition of the triglycerides was analyzed by GC-EI-MS and chemical transformation techniques. Among the 17 compounds, only lauric acid and myristic acid exhibited significant inhibitory effects on the movement of Caenorhabditis elegans with minimum inhibitory concentrations (MIC) of 75 microg/ml. PMID:16163824

Gu, Jian-Qiao; Eppler, C Mark; Montenegro, Gloria; Timmins, Scott D; Timmermann, Barbara N

2005-01-01

150

Novel Microwave-Assisted Synthesis of the Immunomodulator Organotellurium Compound Ammonium Trichloro(dioxoethylene-O,O?)tellurate (AS101)  

PubMed Central

Ammonium trichloro[1,2-ethanediolato-O,O?]-tellurate (AS101) is the most important synthetic Te compound from the standpoint of its biological activity. It is a potent immunomodulator with a variety of potential therapeutic applications and antitumoral action in several preclinical and clinical studies. An experimental design has been used to develop and optimize a novel microwave-assisted synthesis (MAOS) of the AS101. In comparison to the results observed in the literature, refluxing Te(IV) chloride and ethylene glycol in acetonitrile (Method A), or by refluxing Te(IV) chloride and ammonium chloride in ethylene glycol (Method B), it was found that the developed methods in the present work are an effective alternative, because although performance slightly decreases compared to conventional procedures (75% vs. 79% by Method A, and 45% vs. 51% by Method B), reaction times decreased from 4 h to 30 min and from 4 h to 10 min, by Methods A and B respectively. MAOS is proving to be of value in the rapid synthesis of compounds with new and improved biological activities, specially based on the benefit of its shorter reaction times. PMID:24566150

Vázquez-Tato, M. Pilar; Mena-Menéndez, Alberto; Feás, Xesús; Seijas, Julio A.

2014-01-01

151

Novel microwave-assisted synthesis of the immunomodulator organotellurium compound ammonium trichloro(dioxoethylene-O,O')tellurate (AS101).  

PubMed

Ammonium trichloro[1,2-ethanediolato-O,O']-tellurate (AS101) is the most important synthetic Te compound from the standpoint of its biological activity. It is a potent immunomodulator with a variety of potential therapeutic applications and antitumoral action in several preclinical and clinical studies. An experimental design has been used to develop and optimize a novel microwave-assisted synthesis (MAOS) of the AS101. In comparison to the results observed in the literature, refluxing Te(IV) chloride and ethylene glycol in acetonitrile (Method A), or by refluxing Te(IV) chloride and ammonium chloride in ethylene glycol (Method B), it was found that the developed methods in the present work are an effective alternative, because although performance slightly decreases compared to conventional procedures (75% vs. 79% by Method A, and 45% vs. 51% by Method B), reaction times decreased from 4 h to 30 min and from 4 h to 10 min, by Methods A and B respectively. MAOS is proving to be of value in the rapid synthesis of compounds with new and improved biological activities, specially based on the benefit of its shorter reaction times. PMID:24566150

Vázquez-Tato, M Pilar; Mena-Menéndez, Alberto; Feás, Xesús; Seijas, Julio A

2014-01-01

152

Iron redox transformations in continuously photolyzed acidic solutions containing natural organic matter: kinetic and mechanistic insights.  

PubMed

In this work, the various pathways contributing to the formation and decay of Fe(II) in photolyzed acidic solutions containing Suwannee River fulvic acid (SRFA) are investigated. Results of experimental and computational studies suggest that ligand to metal charge transfer (LMCT), superoxide-mediated iron reduction and interaction with reduced organic species that are present intrinsically in SRFA each contribute to Fe(III) reduction with LMCT the most likely dominant pathway under these conditions. Fe(II) oxidation occurs as a result of its interaction with a variety of light-generated species including (i) short-lived organic species, (ii) relatively stable semiquinone-like organic species, and (iii) hydroperoxy radicals. While not definitive, a hypothesis that the short-lived organic species are similar to peroxyl radicals appears most consistent with our experimental and modeling results. The semiquinone-like organic species formed during photolysis by superoxide-mediated oxidation of reduced organic moieties are long-lived in the dark but prone to rapid oxidation by singlet oxygen ((1)O2) under irradiated conditions and thus play a minor role in Fe(II) oxidation in the light. A kinetic model is developed that adequately describes all aspects of the experimental data obtained and which is capable of predicting Fe(II) oxidation rates and Fe(III) reduction rates in the presence of natural organic matter and light. PMID:23879362

Garg, Shikha; Jiang, Chao; Miller, Christopher J; Rose, Andrew L; Waite, T David

2013-08-20

153

1990-1996 Nucleic Acids Research, 1995, Vol. 23, No. 11 Transformation of Escherichia coli with large DNA  

E-print Network

with large DNA, transformation efficiency drops dramati- cally with Increasing size ofthe DNA. Molecules the overall efficiency of each of the conditions tested. INTRODUCTION Transformation of bacteria). High efficiency transformation makes the creation of representative libraries feasible when large

Franks, Robert

154

Quantitative determination of fatty acid compositions in micro-encapsulated fish-oil supplements using Fourier transform infrared (FTIR) spectroscopy.  

PubMed

The research describes a rapid method for the determination of fatty acid (FA) contents in a micro-encapsulated fish-oil (?EFO) supplement by using attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic technique and partial least square regression (PLSR) analysis. Using the ATR-FTIR technique, the ?EFO powder samples can be directly analysed without any pre-treatment required, and our developed PLSR strategic approach based on the acquired spectral data led to production of a good linear calibration with R(2)=0.99. In addition, the subsequent predictions acquired from an independent validation set for the target FA compositions (i.e., total oil, total omega-3 fatty acids, EPA and DHA) were highly accurate when compared to the actual values obtained from standard GC-based technique, with plots between predicted versus actual values resulting in excellent linear fitting (R(2)?0.96) in all cases. The study therefore demonstrated not only the substantial advantage of the ATR-FTIR technique in terms of rapidness and cost effectiveness, but also its potential application as a rapid, potentially automated, online monitoring technique for the routine analysis of FA composition in industrial processes when used together with the multivariate data analysis modelling. PMID:22868135

Vongsvivut, Jitraporn; Heraud, Philip; Zhang, Wei; Kralovec, Jaroslav A; McNaughton, Don; Barrow, Colin J

2012-11-15

155

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

PubMed

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

Winterfield, Craig; van de Voort, F R

2014-12-01

156

Bovine ??-acid glycoprotein, a thermostable version of its human counterpart: insights from Fourier transform infrared spectroscopy and in silico modelling.  

PubMed

?1-Acid glycoprotein (AGP) is a plasma protein and a member of the acute phase response. AGP is known to bind and carry several biologically active compounds, as well as to down-modulate the immune system activities. In this work, the structure of bovine AGP has been investigated by Fourier-Transform infrared spectroscopy. A model structure has been obtained on the basis of human AGP and refined by molecular dynamics. In spite of the similar structure, bovine AGP shows an unexpectedly higher (?20 °C) thermostability than its human counterpart. Inspection of the model structure has pointed out the presence of 12 ionic bridges and 2 sulphur-aromatic interactions, whereas only 6 ionic bridges were detected in human AGP. The high number (9) of glutamic acid residues involved in the ionic interactions might explain the significantly decreased thermostability measured at pH 5.5 (Tm ? 71 °C) with respect to pH 7.4 (Tm ? 81 °C), whereas thermostability of human AGP was only slightly affected by lowering the pH. As in human AGP and several other lipocalins, a temperature-induced molten globule state has been observed in the denaturation pathway of bovine AGP. PMID:24530968

Baldassarre, Maurizio; Galeazzi, Roberta; Maggiore, Beatrice; Tanfani, Fabio; Scirè, Andrea

2014-07-01

157

Synthesis, transformations, and comparative studies of porphyryl acrylic acids and their homologues.  

PubMed

The reactivity of porphyryl acrylates and their homologues was studied systematically and to establish their potential as building blocks for the synthesis of novel tetrapyrroles. A new synthetic approach for multifunctional porphyrins was developed using alpha,beta-unsaturated acyl porphyrins as versatile building blocks with yields of 44-95%. The reaction of acyl chlorides generated in situ with ethyl diazoacetate in the presence of PPh(3) led to the corresponding phosphazine, which was quickly self-transformed into a novel porphyrin beta-keto ester system in up to 78% yield. Comparative studies of the next homologue of acrylic porphyrins, i.e., those bearing an additional CH(2) group next to the double bond of the alpha,beta-unsaturated fragment, showed that these can undergo rearrangement reactions via vinylketenes to yield both regioisomers. Depending on the reaction conditions, this method gives regioselectively access to either a rearrangement product or the product of esterification reactions in yields of 81% or 57%, respectively. Enyne metathesis of novel propargyl esters with allyl porphyrins provided an easy access to 1,3-disubstituted butadienes in up to 76% yield. PMID:19170579

Sergeeva, Natalia N; Bakar, Mohd B; Senge, Mathias O

2009-02-20

158

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...

159

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

USGS Publications Warehouse

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

Monette, M.Y.; Bjornsson, B.T.; McCormick, S.D.

2008-01-01

160

Sphingomyelin and sphingomyelin synthase (SMS) in the malignant transformation of glioma cells and in 2-hydroxyoleic acid therapy  

PubMed Central

The mechanism of action of 2-hydroxyoleic acid (2OHOA), a potent antitumor compound, has not yet been fully elucidated. Here, we show that human cancer cells have markedly lower levels of sphingomyelin (SM) than nontumor (MRC-5) cells. In this context, 2OHOA treatment strongly augments SM mass (4.6-fold), restoring the levels found in MRC-5 cells, while a loss of phosphatidylethanolamine and phosphatidylcholine is observed (57 and 30%, respectively). The increased SM mass was due to a rapid and highly specific activation of SM synthases (SMS). This effect appeared to be specific against cancer cells as it did not affect nontumor MRC-5 cells. Therefore, low SM levels are associated with the tumorigenic transformation that produces cancer cells. SM accumulation occurred at the plasma membrane and caused an increase in membrane global order and lipid raft packing in model membranes. These modifications would account for the observed alteration by 2OHOA in the localization of proteins involved in cell apoptosis (Fas receptor) or differentiation (Ras). Importantly, SMS inhibition by D609 diminished 2OHOA effect on cell cycle. Therefore, we propose that the regulation of SMS activity in tumor cells is a critical upstream event in 2OHOA antitumor mechanism, which also explains its specificity for cancer cells, its potency, and the lack of undesired side effects. Finally, the specific activation of SMS explains the ability of this compound to trigger cell cycle arrest, cell differentiation, and autophagy or apoptosis in cancer cells. PMID:22106271

Barceló-Coblijn, Gwendolyn; Martin, Maria Laura; de Almeida, Rodrigo F. M.; Noguera-Salvà, Maria Antònia; Marcilla-Etxenike, Amaia; Guardiola-Serrano, Francisca; Lüth, Anja; Kleuser, Burhard; Halver, John E.; Escribá, Pablo V.

2011-01-01

161

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

NASA Astrophysics Data System (ADS)

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

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

2014-06-01

162

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

PubMed

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

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

1997-05-01

163

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

Microsoft Academic Search

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

Ki-Hoon Kang; Jerzy Dec; Jean-Marc Bollag

2002-01-01

164

Quantification of hydroxycinnamic acids and lignin in perennial forage and energy grasses by Fourier-transform infrared spectroscopy and partial least squares regression.  

PubMed

Levels of lignin and hydroxycinnamic acid wall components in three genera of forage grasses (Lolium,Festuca and Dactylis) have been accurately predicted by Fourier-transform infrared spectroscopy using partial least squares models correlated to analytical measurements. Different models were derived that predicted the concentrations of acid detergent lignin, total hydroxycinnamic acids, total ferulate monomers plus dimers, p-coumarate and ferulate dimers in independent spectral test data from methanol extracted samples of perennial forage grass with accuracies of 92.8%, 86.5%, 86.1%, 59.7% and 84.7% respectively, and analysis of model projection scores showed that the models relied generally on spectral features that are known absorptions of these compounds. Acid detergent lignin was predicted in samples of two species of energy grass, (Phalaris arundinacea and Pancium virgatum) with an accuracy of 84.5%. PMID:18796351

Allison, Gordon G; Thain, Simon C; Morris, Phillip; Morris, Catherine; Hawkins, Sarah; Hauck, Barbara; Barraclough, Tim; Yates, Nicola; Shield, Ian; Bridgwater, Anthony V; Donnison, Iain S

2009-02-01

165

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

SciTech Connect

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

Grosjean, D. (DGA, Inc., Ventura, CA (USA)); Tuazon, E.C. (Univ. of California, Riverside (USA)); Fujita, E. (California Air Resources Board, Sacramento (USA))

1990-01-01

166

Decreased Rubisco activity leads to dramatic changes of nitrate metabolism, amino acid metabolism and the levels of phenylpropanoids and nicotine in tobacco antisense RBCS transformants.  

PubMed

Tobacco transformants that express an antisense RBCS construct were used to investigate the consequences of a lesion in photosynthetic carbon metabolism for nitrogen metabolism and secondary metabolism. The results show that an inhibition of photosynthesis and decrease in sugar levels leads to a general inhibition of nitrogen metabolism, and dramatic changes in the levels of secondary metabolites. The response was particularly clear in plants that received excess nitrogen. In these conditions, a decrease of Rubisco activity led to an inhibition of nitrate reductase activity, accumulation of nitrate, a decrease of amino acid levels that was larger than the decrease of sugars, and a large decrease of chlorogenic acid and of nicotine, which are the major carbon- and nitrogen-rich secondary metabolites in tobacco leaves, respectively. Similar changes were seen when nitrogen-replete wild-type tobacco was grown in low light. The inhibition of nitrogen metabolism was partly masked when wild-type plants and antisense RBCS transformants were compared in marginal or in limiting nitrogen, because the lower growth rate of the transformants alleviated the nitrogen deficiency, leading to an increase of amino acids. In these conditions, chlorogenic acid always decreased but the decrease of nicotine was ameliorated or reversed. When the changes in internal pools are compared across all the genotypes and growth conditions, two conclusions emerge. First, decreased levels of primary metabolites lead to a dramatic decrease in the levels of secondary metabolites. Second, changes of the amino acid : sugar ratio are accompanied by changes of the nicotine:chlorogenic acid ratio. PMID:12061898

Matt, Petra; Krapp, Anne; Haake, Volker; Mock, Hans-Peter; Stitt, Mark

2002-06-01

167

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

NASA Astrophysics Data System (ADS)

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

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

2015-03-01

168

Negative regulation of the major histocompatibility complex class I enhancer in adenovirus type 12-transformed cells via a retinoic acid response element.  

PubMed Central

In cells transformed by the highly oncogenic adenovirus type 12 (Ad12), the viral E1A proteins mediate transcriptional repression of the major histocompatibility class I genes. In contrast, class I transcription is not reduced in cells transformed by the nononcogenic Ad5. The decreased rate of class I transcription is, at least in part, the result of a reduced major histocompatibility complex class I enhancer activity in Ad12-transformed cells and correlates with an increase in the levels of a DNA-binding activity to the R2 element of the enhancer (R. Ge, A. Kralli, R. Weinmann, and R. P. Ricciardi, J. Virol. 66:6969-6978, 1992). Employing transient transfection assays, we now provide direct evidence that the R2 element can confer repression in Ad12- but not Ad5-transformed cells. Repression by R2 was observed only in the presence of the positive enhancer element R1 and was dependent on (i) the number of the R2 elements and (ii) the relative arrangement of R2 and R1 elements. The putative R2-binding repressor protein, R2BF, was similar in molecular weight and binding specificity to members of the thyroid hormone/retinoic acid (RA) receptor family. RA treatment abrogated the R2-mediated repression in Ad12-transformed cells and had no effect on the activity of R2/R1-containing promoters in Ad5-transformed cells. These results are consistent with the presence of an R2-binding repressor in Ad12-transformed cells. In the absence of RA, the repressor compromises enhancer activity by interfering with the activity of the positive cis element R1. RA treatment of Ad12-transformed cells may render the repressor inactive. Images PMID:1433503

Kralli, A; Ge, R; Graeven, U; Ricciardi, R P; Weinmann, R

1992-01-01

169

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

Microsoft Academic Search

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

Gary D. Gray; Soumitra Basu; Eric Wickstrom

1997-01-01

170

Interleukin8 (IL8) over-production and autocrine cell activation are key factors in monomethylarsonous acid [MMA(III)]-induced malignant transformation of urothelial cells  

Microsoft Academic Search

The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized

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

171

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

PubMed

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

Pande, Ranjana; Mishra, H N

2015-04-01

172

Repair of Deoxyribonucleic Acid in Haemophilus influenzae I. X-Ray Sensitivity of Ultraviolet-sensitive Mutants and Their Behavior as Hosts to Ultraviolet-irradiated Bacteriophage and Transforming Deoxyribonucleic Acid  

PubMed Central

Seven mutants of Haemophilus influenzae were isolated by the criterion of sensitivity to ultraviolet (UV) inactivation of colony formation. These mutants and the wild type were characterized with regard to X-ray inactivation of colony formation, UV induction of division inhibition, the ability of the eight strains to act as recipients to UV-irradiated H. influenzae phage and transforming deoxyribonucleic acid (DNA), and the influence of acriflavine on the survival of UV-irradiated transforming DNA with these strains as recipients. The photoreactivable sector of transforming DNA with yeast photoreactivating enzyme was measured for the most UV-sensitive mutant and was found to be greater than that of wild type. Judged by the above criteria, the order of the strains' sensitivities shows some, but by no means complete, correlation from one type of sensitivity characterization to another, indicating that a minimum of two variables is needed to explain the differences in the strains. Acriflavine increases the UV sensitivity of transforming DNA except in the most sensitive mutant. This effect is usually, but not always, more pronounced in the case of the more UV-resistant marker. The acriflavine effect is postulated to be the result of at least two factors: (i) interference with repair of transforming DNA in the host cell, and (ii) interference with the probability of recombination between transforming DNA and host DNA. Images PMID:5300300

Setlow, Jane K.; Brown, Dianne C.; Boling, Maxon E.; Mattingly, Alice; Gordon, Milton P.

1968-01-01

173

Deletion mapping of moloney type C virus: polypeptide and nucleic acid expression in different transforming virus isolates.  

PubMed Central

The viral polypeptides and viral RNA present in cells transformed by various replication-defective type C viruses derived from Maloney murine leukemia virus were examined. Different portions of the Maloney type C viral genome were retained in the different transforming viruses, thus providing an opportunity for deletion mapping of the Moloney type C genome. DNA transcripts were prepared that are complementary to three distinct nonoverlapping portions of the Moloney viral geonome. Based on an anlysis of the polypeptides produced in the different transformed cells, one complementary DNA apparently respresents sequences coding for Moloney gp70; one complementary DNA represents a region of the Moloney genome common to all of the transforming viruses examined, and one complementary DNA represents the sequences for p30, p15, p10,12. A partial map of the different replication-defective transforming viruses is suggested. PMID:178891

Parks, W P; Howk, R S; Anisowicz, A; Scolnick, E M

1976-01-01

174

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

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

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

2014-01-01

175

RNA Arbitrarily Primed PCR and Fourier Transform Infrared Spectroscopy Reveal Plasticity in the Acid Tolerance Response of Streptococcus macedonicus  

Microsoft Academic Search

We have previously reported that an acid tolerance response (ATR) can be induced in Streptococcus mace- donicus cells at mid-log phase after autoacidification, transient exposure to acidic pH, or acid habituation, as well as at stationary phase. Here, we compared the transcriptional profiles of these epigenetic phenotypes, by RNA arbitrarily primed PCR (RAP-PCR), and their whole-cell chemical compositions, by Fourier

Konstantinos Papadimitriou; Effrossyni Boutou; Georgia Zoumpopoulou; Petros A. Tarantilis; Moschos Polissiou; Constantinos E. Vorgias; Effie Tsakalidou

2008-01-01

176

Oligomerization of 2-methylpropene and transformation of 2,4,4-trimethyl-2-pentene over supported and unsupported perfluorinated resinsulfonic acid catalysts  

SciTech Connect

Oligomerization of 2-methylpropene was studied with two types of supported (on alumina and on silicon carbide) as well neat perfluorinated resinsulfonic acid catalysts. The heterogeneous reactions were carried out over the solid acid catalysts in a continuous flow reactor at temperatures between 85 and 170 C under atmospheric pressure. Under the studied conditions (85 to 105 C, 1 atm pressure, WHSV:1-3 g/g {center dot} h) all catalysts studied are suitable for oligomerization of 2-methyl-propene. Product distributions show regular temperature dependence: upon increasing temperature the molecular weight of oligomers decreases, with no difference in the selectivity of the catalysts. Transformation of 2,4,4-trimethyl-2-pentene in the liquid phase at room temperature shows surprising selectivity using either the hydrated or dehydrated forms of the resinsulfonic acids. In the case of the hydrated forms of the acids, only double bond isomerization takes place. With dehydrated acids oligomerization as well as isomerization occurs. Above 50 C the selectivity is lost.

Bucsi, I.; Olah, G.A. (Univ. of Southern California, University Park, Los Angeles (United States))

1992-09-01

177

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

NASA Astrophysics Data System (ADS)

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

Gardini, A.; Maíz Apellániz, J.; Pérez, E.; Quesada, J. A.; Funke, B.

2013-05-01

178

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

SciTech Connect

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.

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

179

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

PubMed Central

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

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

2013-01-01

180

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)

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.

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

2013-01-01

181

The glucose dependence of Akt-transformed cells can be reversed by pharmacologic activation of fatty acid beta-oxidation.  

PubMed

Activation of the oncogenic kinase Akt stimulates glucose uptake and metabolism in cancer cells and renders these cells susceptible to death in response to glucose withdrawal. Here we show that 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR) reverses the sensitivity of Akt-expressing glioblastoma cells to glucose deprivation. AICAR's protection depends on the activation of AMPK, as expression of a dominant-negative form of AMPK abolished this effect. AMPK is a cellular energy sensor whose activation can both block anabolic pathways such as protein synthesis and activate catabolic reactions such as fatty acid oxidation to maintain cellular bioenergetics. While rapamycin treatment mimicked the effect of AICAR on inhibiting markers of cap-dependent translation, it failed to protect Akt-expressing cells from death upon glucose withdrawal. Compared to control cells, Akt-expressing cells were impaired in the ability to induce fatty acid oxidation in response to glucose deprivation unless stimulated with AICAR. Stimulation of fatty acid oxidation was sufficient to maintain cell survival as activation of fatty acid oxidation with bezafibrate also protected Akt-expressing cells from glucose withdrawal-induced death. Conversely, treatment with a CPT-1 inhibitor to block fatty acid import into mitochondria prevented AICAR from stimulating fatty acid oxidation and promoting cell survival in the absence of glucose. Finally, cell survival did not require reversal of Akt's effects on either protein translation or lipid synthesis as the addition of the cell penetrant oxidizable substrate methyl-pyruvate was sufficient to maintain survival of Akt-expressing cells deprived of glucose. Together, these data suggest that activation of Akt blocks the ability of cancer cells to metabolize nonglycolytic bioenergetic substrates, leading to glucose addiction. PMID:15806154

Buzzai, Monica; Bauer, Daniel E; Jones, Russell G; Deberardinis, Ralph J; Hatzivassiliou, Georgia; Elstrom, Rebecca L; Thompson, Craig B

2005-06-16

182

Differentiation of Different Mixed Listeria Strains and Also Acid-Injured, Heat-Injured, and Repaired Cells of Listeria monocytogenes Using Fourier Transform Infrared Spectroscopy.  

PubMed

Fourier transform infrared (FT-IR) spectroscopy was used to differentiate mixed strains of Listeria monocytogenes and mixed strains of L. monocytogenes and Listeria innocua. FT-IR spectroscopy was also applied to investigate the hypothesis that heat-injured and acid-injured cells would return to their original physiological integrity following repair. Thin smears of cells on infrared slides were prepared from cultures for mixed strains of L. monocytogenes, mixed strains of L. monocytogenes and L. innocua, and each individual strain. Heat-injured and acid-injured cells were prepared by exposing harvested cells of L. monocytogenes strain R2-764 to a temperature of 56 ± 0.2°C for 10 min or lactic acid at pH 3 for 60 min, respectively. Cellular repair involved incubating aliquots of acid-injured and heat-injured cells separately in Trypticase soy broth supplemented with 0.6% yeast extract for 22 to 24 h; bacterial thin smears on infrared slides were prepared for each treatment. Spectral collection was done using 250 scans at a resolution of 4 cm(-1) in the mid-infrared wavelength region. Application of multivariate discriminant analysis to the wavelength region from 1,800 to 900 cm(-1) separated the individual L. monocytogenes strains. Mixed strains of L. monocytogenes and L. monocytogenes cocultured with L. innocua were successfully differentiated from the individual strains when the discriminant analysis was applied. Different mixed strains of L. monocytogenes were also successfully separated when the discriminant analysis was applied. A data set for injury and repair analysis resulted in the separation of acid-injured, heat-injured, and intact cells; repaired cells clustered closer to intact cells when the discriminant analysis (1,800 to 600 cm(-1)) was applied. FT-IR spectroscopy can be used for the rapid source tracking of L. monocytogenes strains because it can differentiate between different mixed strains and individual strains of the pathogen. PMID:25719878

Nyarko, Esmond; Donnelly, Catherine

2015-03-01

183

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

PubMed

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

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

2014-01-01

184

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

PubMed Central

The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50 nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized model of urothelial cells (UROtsa), with only 3 mo of exposure necessary to trigger the transformation-related changes. In the three-month window of exposure, the cells over-expressed pro-inflammatory cytokines (IL-1?, IL-6 and IL-8), consistent with the sustained activation of NFK? and AP1/c-jun, ERK2, and STAT3. IL-8 was over-expressed within hours after exposure to MMA(III), and sustained over-expression was observed during chronic exposure. In this study, we profiled IL-8 expression in UROtsa cells exposed to 50 nM MMA(III) for 1 to 5 mo. IL-8 expression was increased mainly in cells after 3 mo MMA(III) exposure, and its production was also found increased in tumors derived from these cells after heterotransplantation in SCID mice. UROtsa cells do express both receptors, CXCR1 and CXCR2, suggesting that autocrine cell activation could be important in cell transformation. Supporting this observation and consistent with IL-8 over-expression, CXCR1 internalization was significantly increased after three months of exposure to MMA(III). The expression of MMP-9, cyclin D1, bcl-2, and VGEF was significantly increased in cells exposed to MMA(III) for 3 mo, but these mitogen-activated kinases were significantly decreased after IL-8 gene silencing, together with a decrease in cell proliferation rate and in anchorage-independent colony formation. These results suggest a relevant role of IL-8 in MMA(III)-induced UROtsa cell transformation. PMID:22015448

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

2011-01-01

185

Biosynthesis of polyunsaturated fatty acids in the developing brain: II. Metabolic transformations of intracranially administered [3-(14)C] Eicosatrienoic acid, evidence for lack of delta8 desaturase.  

PubMed

[3-(14)C] Eicosatrienoic acid (delta11,14,17) chemically synthesized from [-(14)C] linolenic acid was injected intracranially into 14-day old rats and sacrificed 8 hr later. The analysis of brain fatty acids by radio-gas liquid chromatography before and after ozonolysis showed that the tetraene fraction consisted of a desaturated product, delta5,11,17-20:4, and its elongated product, delta7,13,16,19-22:4. Both of these products, with a combined total of 61% of the total radioactivity recovered in the tetraene fraction, contain a nonmethylene interrupted double bond system and, therefore, are unsuitable for further desaturation. The other two components, delta6,9,12,15-18:4 and delta8,11,14,14-20:4, must have been formed from delta9,12,15-18:3, formed by retroconversion of the starting material 20:3, followed by desaturation and elongation. These results suggest a lack of delta8 desaturase in the developing brain, leading to formation of delta5,11,14,17-20:4 rather than delta8,11,14,17-20:4. However, the nonmethylene interrupted doulbe bond isomer does not restrict chain elongation. PMID:994760

Dhopeshiwarkar, G A; Subramanian, C

1976-09-01

186

Characterization of a newly isolated strain Rhodococcus erythropolis ZJB-09149 transforming 2-chloro-3-cyanopyridine to 2-chloronicotinic acid.  

PubMed

2-Chloronicotinic acid is receiving much attention for its effective applications as a key precursor in the synthesis of pesticides and medicines. In this study, a strain ZJB-09149 converting 2-chloro-3-cyanopyridine to 2-chloronicotinic acid was newly isolated and identified as Rhodococcus erythropolis, based on its physiological and biological tests, and 16S rDNA sequence analysis. In addition, the effects of inducer, carbon source and nitrogen source were examined. Maximum activity was achieved when the above parameters were set as 8 g/l ?-caprolactam, 7 g/l yeast extract and 5 g/l maltose. Moreover, the biotransformation pathway of 2-chloro-3-cyanopyridine to 2-chloronicotinic acid in strain ZJB-09149 was investigated as well. This study revealed that the nitrile hydratase (NHase) and amidase expressed in R. erythropolis ZJB-09149 are responsible for the conversion of 2-chloro-3-cyanopyridine. This is the first time to report on the biotransformation preparation of 2-chloronicotinic acid. PMID:21549865

Jin, Li-Qun; Li, Ya-Fei; Liu, Zhi-Qiang; Zheng, Yu-Guo; Shen, Yin-Chu

2011-10-01

187

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

Microsoft Academic Search

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

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

2005-01-01

188

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

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.

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

2013-12-01

189

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

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

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

2013-11-05

190

Geobacillus stearothermophilus V ubiE gene product is involved in the evolution of dimethyl telluride in Escherichia coli K-12 cultures amended with potassium tellurate but not with potassium tellurite  

Microsoft Academic Search

A 3.8-kb fragment of chromosomal DNA of Geobacillus stearothermophilus V cloned in pSP72 (p1VH) confers resistance to potassium tellurite (K 2TeO 3) and to potassium tellurate (K 2TeO 4) when the encoded genes are expressed in Escherichia coli K-12. The nt sequence of the cloned fragment predicts three ORFs of 780, 399, and 600 bp, whose encoded protein products exhibit about

Manuel A. Araya; Jerry W. Swearingen Jr; Mary F. Plishker; Claudia P. Saavedra; Thomas G. Chasteen; Claudio C. Vásquez

2004-01-01

191

Reactivity and Selectivity of Charged Phenyl Radicals Toward Amino Acids in a Fourier-Transform Ion Cyclotron Resonance (FT-ICR) Mass Spectrometer  

PubMed Central

The reactivity of ten charged phenyl radicals toward several amino acids was examined in the gas phase in a dual-cell Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer. All radicals abstract a hydrogen atom from the amino acids, as expected. The most electrophilic radicals (with a greater calculated vertical electron affinity (EA) at the radical site) also react with these amino acids via NH2 abstraction (a nonradical nucleophilic addition-elimination reaction). Both the radical (hydrogen atom abstraction) and nonradical (NH2 abstraction) reaction efficiencies were found to increase with the electrophilicity (EA) of the radical. However, NH2 abstraction is more strongly influenced by EA. In contrast to an earlier report, the ionization energies of the amino acids do not appear to play a general reactivity controlling role. Studies using several partially deuterium-labeled amino acids revealed that abstraction of a hydrogen atom from the ?-carbon is only preferred for glycine; for the other amino acids, a hydrogen atom is preferentially abstracted from the side chain. The electrophilicity of the radicals does not appear to have a major influence on the site from which the hydrogen atom is abstracted. Hence, the regioselectivity of hydrogen atom abstraction appears to be independent of the structure of the radical but dependent on the structure of the amino acid. Surprisingly, abstraction of two hydrogen atoms was observed for the 3-nitro-5-dehydrophenyl pyridinium radical, indicating that substituents on the radical not only influence the EA of the radical but also can be involved in the reaction. In disagreement with an earlier report, proline was found to display several unprecedented reaction pathways that likely do not proceed via a radical mechanism but rather by a nucleophilic addition-elimination mechanism. Both NH2 and 15NH2 groups were abstracted from lysine labeled with 15N on the side-chain, indicating that NH2 abstraction occurs both from the amino terminus as well as from the side-chain. Quantum chemical calculations were employed to obtain insights into some of the reaction mechanisms. PMID:21612203

Pates, George O.; Guler, Leonard; Nash, John J.; Kenttämaa, Hilkka I.

2011-01-01

192

Acid-promoted transformations of 1-(diphenylphosphoryl)allenes: synthesis of novel 1,4-dihydrophosphinoline 1-oxides.  

PubMed

1-(Diphenylphosphoryl)alka-1,2-dienes (phosphonoallenes) in Brønsted (super)acids (TfOH, FSO3H, and H2SO4) at -70 to 120 °C for 30 min to 4 h gave, at first, (3-hydroxyalk-1-en-1-yl)diphenylphosphine oxides, as kinetically favorable reaction products, that are further converted into 1-phenyl-1,4-dihydrophosphinoline 1-oxides as thermodynamically stable compounds. The latter compounds are formed from phosphonoallenes under the action of a strong Lewis acid AlCl3 at room temperature for 10-120 min. This is a novel, simple and efficient (short reaction time, high yields) method for synthesis of such 1,4-dihydrophosphinoline 1-oxides. PMID:25526497

Bogachenkov, Alexander S; Dogadina, Albina V; Boyarskiy, Vadim P; Vasilyev, Aleksander V

2015-02-01

193

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

PubMed

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

R Dos Santos, Tatiane; Harnisch, Falk; Nilges, Peter; Schröder, Uwe

2015-03-01

194

Influence of the Lewis acidity of indium-modified beta zeolite in the m-xylene transformation  

Microsoft Academic Search

The catalytic performance of NH4-beta zeolite containing different amounts of indium, introduced as In+ cations by the method of reductive solid-state ion exchange (RSSIE), has been studied in the m-xylene conversion. It has been shown that In cations regarded as coordinatively unsaturated species possessing Lewis acidity substantially change the catalyst stability and the selectivity of the reaction when performed in

Vesselina P. Mavrodinova; Margarita D. Popova; Yanka G. Neinska; Christo I. Minchev

2001-01-01

195

Pseudomonas resinovorans SPR1, a newly isolated strain with potential of transforming eugenol to vanillin and vanillic acid.  

PubMed

In this study a novel strain was isolated with the capability to grow on eugenol as a source of carbon and energy. This strain was identified as Pseudomonas resinovorans (GenBank accession no. HQ198585) based on phenotypic characterization and phylogenetic analysis of 16S rDNA gene. The intermediates coniferyl alcohol, coniferyl aldehyde, ferulic acid, vanillin and vanillic acid were detected in the culture supernatant during eugenol biotransformation with this strain. The products were confirmed by thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and spectral data achieved from UV-vis, FTIR and mass spectroscopy. Using eugenol as substrate and resting cells of P. resinovorans SPR1, which were harvested at the end of the exponential growth phase, without further optimization 0.24 g/L vanillin (molar yield of 10%) and 1.1g/L vanillic acid (molar yield of 44%) were produced after 30 h and 60 h biotransformation, respectively. The current work gives the first evidence for the eugenol biotransformation by P. resinovorans. PMID:21689800

Ashengroph, Morahem; Nahvi, Iraj; Zarkesh-Esfahani, Hamid; Momenbeik, Fariborz

2011-10-01

196

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

SciTech Connect

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

Escudero-Lourdes, C., E-mail: cescuder@uaslp.mx [Centro de Investigación y Estudios de Posgrado (CIEP), Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí (Mexico); Wu, T.; Camarillo, J.M.; Gandolfi, A.J. [Department of Pharmacology and Toxicology College of Pharmacy, University of Arizona. Tucson, AZ (United States)] [Department of Pharmacology and Toxicology College of Pharmacy, University of Arizona. Tucson, AZ (United States)

2012-01-01

197

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

SciTech Connect

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.

Ying Yibin; Liu Yande; Tao Yang

2005-09-01

198

Effect of preozonation on the characteristic transformation of fulvic acid and its subsequent trichloromethane formation potential: presence or absence of bicarbonate.  

PubMed

The effects of bicarbonate on the characteristic transformation of fulvic acid (FA) and its subsequent trichloromethane formation potential (TCMFP) were investigated in the process of preozonation. Dissolved organic carbon (DOC) removal rate and the residual aqueous ozone concentration during preozonation were measured with different bicarbonate concentration. The presence of bicarbonate inhibited DOC removal and decreased TCMFP yields in the initial oxidation period. In order to explain these phenomena, the molecular weight (MW) distribution (<5, 5-10, 10-30, and >30 kDa) and corresponding TCMFP were investigated for FA and its subsequent oxidation products. Furthermore, transformation of molecular structure, based on MW distribution, was also characterized with Fourier transform infrared (FTIR) spectrum. Bicarbonate showed different inhibiting effects on TCMFP of organic species with different MW, and more significant TCMFP decrement was observed for the high MW fraction (>30 kDa) than for the low MW fractions. Preozonation led to obvious reduction on DOC and UV254 in most of MW fractions wherever bicarbonate was present or not, demonstrating that ozone contributed to both organics mineralization and structure variation, synchronously. As being indicated from the results of FTIR and gas chromatography-mass spectrometry, the functional groups such as alcohols, epoxides and phenols, the formation of which was promoted with hydroxyl radicals (.OH) and would be remarkably inhibited by bicarbonate, were responsible for the increment of TCM precursor's concentration during ozonation. Results of these studies confirmed low dosage bicarbonate affecting the ozonation pathways, influencing the intermediate species formation and impacting its subsequent TCMFP yields through inhibiting the .OH radicals reactions mainly occurred in high MW fractions. PMID:18328531

Li, Jing; Liu, Huijuan; Zhao, Xu; Qu, Jiuhui; Liu, Ruiping; Ru, Jia

2008-04-01

199

[Construction of a recombinant Escherichia coli BL21/ pET-28a-lpgad and the optimization of transformation conditions for the efficient production of gamma-aminobutyric acid].  

PubMed

In order to enhance gamma-aminobutyric acid production from L-glutamate efficiently, we amplified the key enzyme glutamate decarboxylase (GAD) encoding gene lpgad from the strain Lactobacillus plantarum GB 01-21 which was obtained by way of multi-mutagenesis and overexpressed it in E. coli BL21. Then we purified GAD by Ni-NTA affinity chromatography and characterized the enzyme to optimize the conditions of the whole-cell transformation. The results showed that the recombinant E. coli BL21 (pET-28a-lpgad) produced 8.53 U/mg GAD, which was increased by 3.24 fold compared with the GAD activity in L. plantarum. The optimum pH and temperature of the enzyme were pH 4.8 and 37 degrees C, respectively. At the same time, we found that Ca2+ and Mg2+ could increase the activity significantly. Based on this, we investigated gamma-aminobutyric acid transformation in 5 L fermentor under the optimum transformation conditions. Accordingly, the yield of gamma-aminobutyric acid was 204.5 g/L at 24 h when the 600 g L-glutamate was added and the mole conversion rate had reached 97.92%. The production of gamma-aminobutyric acid was improved by 42.5% compared with that under the unoptimized transformation conditions. This paved a way for the gamma-aminobutyric acid construction of the industrial applications. PMID:22667110

Tian, Lingzhi; Xu, Meijuan; Rao, Zhiming

2012-01-01

200

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

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.

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

201

Expression and Functional Characterization of the Agrobacterium VirB2 Amino Acid Substitution Variants in T-pilus Biogenesis, Virulence, and Transient Transformation Efficiency  

PubMed Central

Agrobacterium tumefaciens is a phytopathogenic bacterium that causes crown gall disease by transferring transferred DNA (T-DNA) into the plant genome. The translocation process is mediated by the type IV secretion system (T4SS) consisting of the VirD4 coupling protein and 11 VirB proteins (VirB1 to VirB11). All VirB proteins are required for the production of T-pilus, which consists of processed VirB2 (T-pilin) and VirB5 as major and minor subunits, respectively. VirB2 is an essential component of T4SS, but the roles of VirB2 and the assembled T-pilus in Agrobacterium virulence and the T-DNA transfer process remain unknown. Here, we generated 34 VirB2 amino acid substitution variants to study the functions of VirB2 involved in VirB2 stability, extracellular VirB2/T-pilus production and virulence of A. tumefaciens. From the capacity for extracellular VirB2 production (ExB2+ or ExB2?) and tumorigenesis on tomato stems (Vir+ or Vir?), the mutants could be classified into three groups: ExB2?/Vir?, ExB2?/Vir+, and ExB2+/Vir+. We also confirmed by electron microscopy that five ExB2?/Vir+ mutants exhibited a wild-type level of virulence with their deficiency in T-pilus formation. Interestingly, although the five T-pilus?/Vir+ uncoupling mutants retained a wild-type level of tumorigenesis efficiency on tomato stems and/or potato tuber discs, their transient transformation efficiency in Arabidopsis seedlings was highly attenuated. In conclusion, we have provided evidence for a role of T-pilus in Agrobacterium transformation process and have identified the domains and amino acid residues critical for VirB2 stability, T-pilus biogenesis, tumorigenesis, and transient transformation efficiency. PMID:24971727

Wu, Hung-Yi; Chen, Chao-Ying; Lai, Erh-Min

2014-01-01

202

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

PubMed

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

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

2015-05-01

203

The N-terminal 178-amino-acid domain only of the SV40 large T antigen acts as a transforming suppressor of the HER-2/neu oncogene.  

PubMed

The deregulation of the HER-2/neu protooncogene was demonstrated in a wide variety of human cancers and shown to be correlated with the progress of malignancy and metastasis in animal models. Repression of HER-2/neu overexpression suppressed the malignant phenotypes of HER-2/neu-overexpressing cancer cells. This suggested that HER-2/neu may be a good target for developing anti-cancer drugs. We found a deletion mutant of simian virus 40 (SV40) large T antigen (LT) suppresses the HER-2/neu oncogene expression at the transcriptional level. PCR clones of this mutant SV40LT, named LT425, which contains the N-terminal region of amino acid residues 1-178 of SV40LT, were subcloned and stably transfected into the HER-2/neu-overexpressing human ovarian cancer SKOV3.ip1 cells. These LT425 clones were found to be able to down-regulate the endogenous production of p185(HER-2/neu). In addition, the LT425-expressing stable transfectants showed reduced growth rate, low soft agarose colony forming ability, and low tumorigenic potential as compared with the parental line. These data suggested that the N-terminal 178 amino acids domain only of SV40LT may act as a transforming repressor of HER-2/neu oncogene. PMID:9484845

Kao, M C; Liu, G Y; Chuang, T C; Lin, Y S; Wuu, J A; Law, S L

1998-01-29

204

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...

205

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

PubMed

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

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

2014-05-01

206

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

NASA Astrophysics Data System (ADS)

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

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

2013-04-01

207

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

SciTech Connect

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

Rieble, S.; Beale, S.I. (Brown Univ., Providence, RI (USA))

1989-04-01

208

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)

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.

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

2013-06-01

209

Protonation states of membrane-embedded carboxylic acid groups in rhodopsin and metarhodopsin II: a Fourier-transform infrared spectroscopy study of site-directed mutants.  

PubMed Central

A method was developed to measure Fourier-transform infrared (FTIR) difference spectra of detergent-solubilized rhodopsin expressed in COS cells. Experiments were performed on native bovine rhodopsin, rhodopsin expressed in COS cells, and three expressed rhodopsin mutants with amino acid replacements of membrane-embedded carboxylic acid groups: Asp-83-->Asn (D83N), Glu-122-->Gln (E122Q), and the double mutant D83N/E122Q. Each of the mutant opsins bound 11-cis-retinal to yield a visible light-absorbing pigment. Upon illumination, each of the mutant pigments formed a metarhodopsin II-like species with maximal absorption at 380 nm that was able to activate guanine nucleotide exchange by transducin. Rhodopsin versus metarhodopsin II-like photoproduct FTIR-difference spectra were recorded for each sample. The COS-cell rhodopsin and mutant difference spectra showed close correspondence to that of rhodopsin from disc membranes. Difference bands (rhodopsin/metarhodopsin II) at 1767/1750 cm-1 and at 1734/1745 cm-1 were absent from the spectra of mutants D83N and E122Q, respectively. Both bands were absent from the spectrum of the double mutant D83N/E122Q. These results show that Asp-83 and Glu-122 are protonated both in rhodopsin and in metarhodopsin II, in agreement with the isotope effects observed in spectra measured in 2H2O. A photoproduct band at 1712 cm-1 was not affected by either single or double replacements at positions 83 and 122. We deduce that the 1712 cm-1 band arises from the protonation of Glu-113 in metarhodopsin II. PMID:7901852

Fahmy, K; Jäger, F; Beck, M; Zvyaga, T A; Sakmar, T P; Siebert, F

1993-01-01

210

Protonation states of membrane-embedded carboxylic acid groups in rhodopsin and metarhodopsin II: a Fourier-transform infrared spectroscopy study of site-directed mutants.  

PubMed

A method was developed to measure Fourier-transform infrared (FTIR) difference spectra of detergent-solubilized rhodopsin expressed in COS cells. Experiments were performed on native bovine rhodopsin, rhodopsin expressed in COS cells, and three expressed rhodopsin mutants with amino acid replacements of membrane-embedded carboxylic acid groups: Asp-83-->Asn (D83N), Glu-122-->Gln (E122Q), and the double mutant D83N/E122Q. Each of the mutant opsins bound 11-cis-retinal to yield a visible light-absorbing pigment. Upon illumination, each of the mutant pigments formed a metarhodopsin II-like species with maximal absorption at 380 nm that was able to activate guanine nucleotide exchange by transducin. Rhodopsin versus metarhodopsin II-like photoproduct FTIR-difference spectra were recorded for each sample. The COS-cell rhodopsin and mutant difference spectra showed close correspondence to that of rhodopsin from disc membranes. Difference bands (rhodopsin/metarhodopsin II) at 1767/1750 cm-1 and at 1734/1745 cm-1 were absent from the spectra of mutants D83N and E122Q, respectively. Both bands were absent from the spectrum of the double mutant D83N/E122Q. These results show that Asp-83 and Glu-122 are protonated both in rhodopsin and in metarhodopsin II, in agreement with the isotope effects observed in spectra measured in 2H2O. A photoproduct band at 1712 cm-1 was not affected by either single or double replacements at positions 83 and 122. We deduce that the 1712 cm-1 band arises from the protonation of Glu-113 in metarhodopsin II. PMID:7901852

Fahmy, K; Jäger, F; Beck, M; Zvyaga, T A; Sakmar, T P; Siebert, F

1993-11-01

211

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

PubMed Central

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

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

1989-01-01

212

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

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.

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

213

Modeling Transformation  

E-print Network

pGLO plasmids Bacterial chromosomal DNA Cell membrane #12;Heat-shock @ 42°C IncreasesModeling Transformation What does each step do? #12;Transformation Procedure #12;Transformation Procedure #12;Building Your Model Yarn = chromosomal DNA Beads

Rose, Michael R.

214

Inhibition of cyclooxygenase-2 expression and restoration of gap junction intercellular communication in H-ras-transformed rat liver epithelial cells by caffeic acid phenethyl ester.  

PubMed

One of the most frequent defects in human cancers is the uncontrolled activation of the ras signaling pathways. Increased expression of cyclooxygenase-2 (COX-2) and inhibition of gap junction intercellular communication (GJIC) have been frequently observed in several forms of human malignancies. The present study investigated the effects of caffeic acid phenethyl ester (CAPE), a chemopreventive phytochemical derived from honey propolis, on COX-2 expression and GJIC in Harvey-ras-transformed WB-F344 rat liver epithelial cells (H-ras WB cells). H-ras induced COX-2 expression in WB-F344 rat liver epithelial cells (WB cells). H-ras WB cells also exhibited complete inhibition of GJIC and predominant unphosphorylation of connexin 43 (Cx43), a major protein modulating GJIC. CAPE significantly inhibited the constitutive expression of COX-2 and restored the disrupted GJIC through the phosphorylation of Cx43 at a concentration of 12.5 microM in H-ras WB cells. Although the molecular basis for the cancer chemopreventive activity of CAPE is not completely understood, several studies suggest that CAPE is a potent and specific inhibitor of the transcription factor nuclear factor kappaB (NF-kappaB) activation. We also found that CAPE significantly inhibited H-ras-induced NF-kappaB DNA-binding activity without affecting the activation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase, which are major intracellular molecules involved in the Ras signaling pathways. In conclusion, CAPE may exert cancer chemopreventive effects through the inhibition of COX-2 expression and the restoration of disrupted GJIC induced by H-ras, possibly by targeting NF-kappaB. PMID:15659835

Lee, Ki Won; Chun, Kyung-Soo; Lee, Jeong-Sang; Kang, Kyung-Sun; Surh, Young-Joon; Lee, Hyong Joo

2004-12-01

215

A Single Amino Acid Substitution in the v-Eyk Intracellular Domain Results in Activation of Stat3 and Enhances Cellular Transformation  

Microsoft Academic Search

The receptor tyrosine kinase Eyk, a member of the Axl\\/Tyro3 subfamily, activates the STAT pathway and transforms cells when constitutively activated. Here, we compared the potentials of the intracellular domains of Eyk molecules derived from c-Eyk and v-Eyk to transform rat 3Y1 fibroblasts. The v-Eyk molecule induced higher numbers of transformants in soft agar and stronger activation of Stat3; levels

DANIEL BESSER; JACQUELINE F. BROMBERG; HIDESABURO HANAFUSA

1999-01-01

216

Molecfit: Telluric absorption correction tool  

NASA Astrophysics Data System (ADS)

Molecfit corrects astronomical observations for atmospheric absorption features based on fitting synthetic transmission spectra to the astronomical data, which saves a significant amount of valuable telescope time and increases the instrumental efficiency. Molecfit can also estimate molecular abundances, especially the water vapor content of the Earth’s atmosphere. The tool can be run from a command-line or more conveniently through a GUI.

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

2015-01-01

217

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

Microsoft Academic Search

Nervonic acid is a Very Long-Chain Monounsaturated Fatty Acid (VLCMFA), 24:1 ?15 (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

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

2009-01-01

218

Transformation Composition  

E-print Network

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

Drewes, Frank

219

transformations: representations  

E-print Network

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

Nguyen, Dat H.

220

Transformation Station  

NSDL National Science Digital Library

Shapes are all over the place in geometry. One way we can move these shapes is with transformations. Use these games to help you practice and identify the three types of transformations: reflections, translations, and rotations. Just as a refresher, watch this video about transformational geometry: Gingerbread Transformer! When you are ready...start playing the games!! Take it to the court for Basketball Geometry! Once you type in your name and choose a player, pay attention to the coach for a review on the three types of transformations. While you play, ...

Mrs. Stroud

2010-09-01

221

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

Microsoft Academic Search

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

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

1984-01-01

222

Pyrolysis of alanine and ?-aminoisobutyric acid: identification of less-volatile products using gas chromatography\\/Fourier transform infrared spectroscopy\\/mass spectrometry  

Microsoft Academic Search

In addition to volatile low-molecular-weight decomposition compounds, ?-aminoisobutyric acid (Aib) and alanine (Ala) pyrolysis at 500°C under nitrogen atmosphere leads to less-volatile products resulting from amino acid intermolecular condensation. The major pathway is the formation of cyclic dipeptides piperazine-2,5-diones with the yields of 1% for Aib and 68% for Ala. To identify other pyrolysis products, they have been extracted by

Vladimir A Basiuk; Rafael Navarro-González; Elena V Basiuk

1998-01-01

223

Enzymatic transformation of 2-O-?- d-glucopyranosyl- l-ascorbic acid (AA2G) by immobilized ?-cyclodextrin glucanotransferase from recombinant Escherichia coli  

Microsoft Academic Search

This work aims to produce 2-O-?-d-glucopyranosyl-l-ascorbic acid (AA-2G) from ascorbic acid and ?-cyclodextrin with immobilized ?-cyclodextrin glucanotransferase (?-CGTase) from recombinant Escherichia coli. Molecular sieve (SBA-15) was used as an adsorbent, and sodium alginate was used as a carrier, and glutaraldehyde (GA) was used as a cross-linker. The effects of several key variables on ?-CGTase immobilization were examined, and optimal immobilization

Zichen Zhang; Jianghua Li; Long Liu; Jun Sun; Zhaozhe Hua; Guocheng Du; Jian Chen

2011-01-01

224

[Potential antiallergics. 3. Synthesis and transformations of 1,4-dihydro-4-oxo-(1)benzothieno(3,2-b)pyridine-2-carboxylic acid esters].  

PubMed

The title compounds 2a, b are obtained by reaction of potassium 3-amino benzo[b]thiophene-2-carboxylate (1) with acetylenedicarboxylic acid esters in acetic acid. The substance 2a gives the carboxylic acid 2c by saponification, reaction with phosphoryl chloride affords the 4-chloropyridine 3. The carbinol 4, received by boranate reduction, was dehydrogenated with activated manganese dioxide to yield the carbaldehyde 5. Compound 2a reacts with methyliodide to give a separable mixture of the O- and N-alkylated products 6a and 7a, while by reaction of 2b with ethyliodide only the 4-ethoxypyridine 6b is formed. The carboxylic acids 6c, 7b are obtained by alkaline hydrolysis of the esters 6a, 7a. The carbinols 8, 9, formed by reduction of the esters 6a, 7a, are oxidized to give the carbaldehydes 10, 11. The 1H-tetrazoles 17, 18 are synthesized from the aldehydes 10, 11 via the aldoximes 13, 14 and the nitriles 15, 16. The aldehydes 10, 11 react with the beta-aminocrotonic acid esters 19 in acetic acid to yield the 1,4-dihydropyridines (DHP) 20, 21, which are dehydrogenated to form the pyridines (Py) 22, 23. The half-wave potentials E1/2 of the redox system DHP/Py is determined by difference pulse voltammetry using nifedipine as reference substance. PMID:11031766

Görlitzer, K; Kramer, C

2000-09-01

225

Petroleomics: Applications in the Fingerprinting of the Acidic and Basic Crude Oil Components Detected by Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry  

Microsoft Academic Search

We have previously demonstrated the ability of electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) to resolve and identify the polar species found in all petroleum distillates. The ultrahigh resolving power and mass accuracy of FT-ICR MS allows for the identification of thousands of compounds in crude oils without prior chromatographic separation. In Chapter 3, we

Geoffrey Christoffersen Klein

2005-01-01

226

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

Technology Transfer Automated Retrieval System (TEKTRAN)

Marek’s disease virus encoded oncoprotein, Meq, has been shown to play a major role in transformation of T-lymphocytes. We have earlier shown that replacement of the meq gene in the very virulent strain Md5 with that of vaccine strain CVI988/Rispens resulted in virus attenuation in chickens. To dete...

227

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

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

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

2009-03-01

228

Animating Transformations  

NSDL National Science Digital Library

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.

Roberts, Lila F.

2003-01-24

229

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

NASA Astrophysics Data System (ADS)

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

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

2009-12-01

230

Emissions of formaldehyde, acetic acid, methanol, and other trace gases from biomass fires in North Carolina measured by airborne Fourier transform infrared spectroscopy  

Microsoft Academic Search

Biomass burning is an important source of many trace gases in the global troposphere. We have constructed an airborne trace gas measurement system consisting of a Fourier transform infrared spectrometer (FTIR) coupled to a ``flow-through'' multipass cell (AFTIR) and installed it on a U.S. Department of Agriculture Forest Service King Air B-90. The first measurements with the new system were

R. J. Yokelson; J. G. Goode; D. E. Ward; R. A. Susott; R. E. Babbitt; D. D. Wade; I. Bertschi; D. W. T. Griffith; W. M. Hao

1999-01-01

231

Sodium-Stimulated Active Transport of Aminoisobutyric Acid by Reconstituted Vesicles from Partially Purified Plasma Membranes of Mouse Fibroblasts Transformed by Simian Virus 40  

Microsoft Academic Search

Plasma membrane fractions isolated from mouse fibroblast BALB\\/c 3T3 cells transformed by simian virus 40 were partially purified by treatment with dimethylmaleic anhydride followed by extraction with 2% cholate. The extracted proteins were combined with exogenous phospholipids and eluted through a Sephadex G50 column. Reconstituted vesicles thus obtained were shown to possess the ability of Na+-stimulated transport of alpha -aminoisobutyric

Hoyoku Nishino; Loyal G. Tillotson; Robert M. Schiller; Ken-Ichi Inui; Kurt J. Isselbacher

1978-01-01

232

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

- synthesis are severely inhibited by the presence of polyunsatu- rates: 18:2 and 20:4 were inhibitory while saturates and mono- unsaturates (monoenes) had no effect. In addition, these long- chain polyunsaturated fatty acids (PUFA) inhibit acetate uptake...-workers (57) found no significant whole-cell lipid-class modifications but found a decrease in the ratio of PC/PE in plasma membrane. In general, 18:2-supplementation produces an increased satu- rate-unsaturated FA ratio in total lipid fatty acid methyl...

Pierce-Ruhland, Richard Arthur

1981-01-01

233

Transformations of Toxic Metals and Metalloids by Pseudomonas stutzeri Strain KC and its Siderophore Pyridine2,6-bis(thiocarboxylic acid)  

Microsoft Academic Search

\\u000a Pyridine-2,6-bis(thiocarboxylic acid)Pyridine-2,6-bis(thiocarboxylic acid) (pdtc)(pdtc) is a siderophore produced by Pseudomonas stutzeri KCPseudomonas stutzeri KC that plays a role in conditioning the bacterial environment. It serves as a siderophore in solubilizing\\u000a ferric iron and other micronutrient metals, and as a thiol-containing compound, it reacts with toxic heavy metals and metalloids,\\u000a reducing metals like Cr(VI), Se(IV), and Te(IV) and precipitating metals as

Anna M. Zawadzka; Andrzej J. Paszczynski; Ronald L. Crawford

234

Stable and temperature-sensitive transformation of rat kidney epithelial cells suppresses expression of acidic fibroblast growth factor 1 but activates secretion of fibroblast growth factor 3 (int-2) and vascular endothelial growth factor.  

PubMed

Rat kidney proximal tubule epithelial cells (RPTE) in primary culture express acidic fibroblast growth factor 1 (FGF-1). Transformation of RPTE by SV40 (SV-RPTE) suppressed FGF-1 expression but activated secretion of FGF-like factor(s). SV-RPTE conditioned medium contained growth-promoting activity for SV-RPTE and human umbilical vein endothelial cells, indicating that both autocrine and angiogenic factors were secreted. Reverse transcriptase-polymerase chain reaction and Northern analysis for various FGFs showed that only FGF-3, also known as int-2, mRNA was expressed in SV-RPTE. In addition, expression of mRNA for the heparin-binding angiogenic factor vascular endothelial growth factor (VEGF) increased dramatically in SV-RPTE. Physical characterization of the activity in the SV-RPTE conditioned medium suggested that FGF-3 and VEGF contributed the autocrine and angiogenic activities, respectively. We also investigated FGF-3 and VEGF secretion in temperature-sensitive (ts) SV40-transformed RPTE. tsSV-RPTE had transformed properties resembling those of SV-RPTE only at the permissive temperature (33 degrees C), e.g., increased growth potential and anchorage-independent growth. FGF-1 was expressed only at the nonpermissive temperature. VEGF mRNA levels and secretion of the human umbilical vein endothelial cell growth-promoting activity were reduced by switching tsSV-RPTE cells from 33 degrees to 39 degrees C. However, FGF-3 mRNA levels were not affected significantly by the temperature switch suggesting that activation of VEGF and FGF-3 occurs through different mechanisms. These results indicate that FGF-1 expression in RPTE is suppressed by SV40 transformation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7519042

Zhang, G; Sato, J D; Herley, M T; Tsang, M W; Ye, H; Liu, H; Ichimura, T; Yan, G; McKeehan, W L; Stevens, J L

1994-04-01

235

Transformational leadership.  

PubMed

This month, the director of the Magnet Recognition Program® takes an in-depth look at the Magnet® model component transformational leadership. The author examines the expectations for Magnet organizations around this component. What are the qualities that make a nursing leader truly transformational, and what is the best approach to successfully lead a healthcare organization through today's volatile healthcare environment? PMID:22094611

Luzinski, Craig

2011-12-01

236

Transformational Events  

ERIC Educational Resources Information Center

Transformational Events is a new pedagogic pattern that explains how innovations (and other transformations) happened. The pattern is three temporal stages: an interval of increasingly unsatisfactory ad hoc solutions to a persistent problem (the "mess"), an offer of an invention or of a new way of thinking, and a period of widespread adoption and…

Denning, Peter J.; Hiles, John E.

2006-01-01

237

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

EPA Science Inventory

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

238

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...

239

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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

240

Effects of oleic acid/propylene glycol on rat abdominal stratum corneum: lipid extraction and appearance of propylene glycol in the dermis measured by Fourier transform infrared/attenuated total reflectance (FT-IR/ATR) spectroscopy.  

PubMed

Fourie transform infrared/attenuated total reflection analysis demonstrated that the absorbance intensity of C = O stretching bands, which reflect the amounts of lipids in the stratum corneum, decreased with an increase in the duration of skin treatment with 0.15 M oleic acid/propylene glycol (PG) system, suggesting that the oleic acid/PG system induced the lipid extraction, which was followed by a reorganization of the stratum corneum structures. The spectral peaks which originated from the PG molecule were detected in dermal tissues after 30 min of treatment of the stratum corneum with the same system. This observation suggested that the reorganization of the lipid domains due to the lipid extraction by the oleic acid/PG system helped the PG molecules enter the dermal tissues. It was also suggested that an effective volume within the stratum corneum for solutes and/or solvents which could penetrate through the inter-, and/or intracellular routes could be altered in conjunction with the structural changes of the lipids. PMID:8403091

Takeuchi, Y; Yasukawa, H; Yamaoka, Y; Takahashi, N; Tamura, C; Morimoto, Y; Fukushima, S; Vasavada, R C

1993-08-01

241

Lightweight transformer  

SciTech Connect

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.

Swallom, D.W.; Enos, G.

1990-05-01

242

Microbial utilization and transformation of humic acid-like substances extracted from a mixture of municipal refuse and sewage sludge disposed of in a landfill  

Microsoft Academic Search

The purpose of the research was to establish whether humic acid-like substances (HA) related to municipal refuse disposed of in a landfill can resist microbial degradation and if they contribute, in that way, to long-term stabilization of landfill refuse. Using a mixture of 0.1 M Na4P2O7 + 0.1 M NaOH, we extracted HA from municipal refuse mixed with sewage sludge

Z Filip; W Pecher; J Berthelin

2000-01-01

243

Binding of DNA from Bacillus subtilis on Montmorillonite-Humic Acids-Aluminum or Iron Hydroxypolymers: Effects on Transformation and Protection against DNase  

Microsoft Academic Search

Despite the relatively large number of papers dealing with the adsorption of DNA on clays and HA, essen- The equilibrium adsorption and binding of DNA from Bacillus sub- tially no information is available about the adsorption tilis on complexes of montmorillonite-humic acids Al or Fe hydroxy- polymers (Al-M-HA or Fe-M-HA) at different M\\/HA ratios, the of DNA on organomineral particles,

Carmine Crecchio; Pacifico Ruggiero; Maddalena Curci; Claudio Colombo; Giuseppe Palumbo; Guenther Stotzky

244

Organelle transformation.  

PubMed

The source of genetic information in a plant cell is contained in nucleus, plastids, and mitochondria. Organelle transformation is getting a lot of attention nowadays because of its superior performance over the conventional and most commonly used nuclear transformation for obtaining transgenic lines. Absence of gene silencing, strong predictable transgene expression, and its application in molecular pharming, both in pharmaceutical and nutraceuticals, are some of many advantages. Other important benefits of utilizing this technology include the absence of transgene flow, as organelles are maternally inherited. This may increase the acceptability of organelle transformation technology in the development of transgenic crops in a wider scale all over the globe. As the need for crop productivity and therapeutic compounds increases, organelle transformation may be able to bridge the gap, thereby having a definite promise for the future. PMID:22610643

Bhattacharya, Anjanabha; Kumar, Anish; Desai, Nirali; Parikh, Seema

2012-01-01

245

Transformation Golf  

NSDL National Science Digital Library

In this game students use the isometric transformations (sliding, flipping and turning) to sink a golf ball into a cup. There are nine holes in the course and learners are challenged to meet or break a par score.

2011-01-01

246

Transformative copy  

E-print Network

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 ...

Offenhuber, Dietmar

2008-01-01

247

Transforming California  

NSDL National Science Digital Library

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.

Thomas McGuire

2001-01-01

248

Triple transformation  

NASA Astrophysics Data System (ADS)

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

Khan, Farrukh I.; Schinn, Dustin S.

2013-08-01

249

Time variation of the electromagnetic field transfer function by using a wavelet transformation  

NASA Astrophysics Data System (ADS)

Crustal activities, such as large earthquakes and volcanic eruptions, may affect electromagnetism structure changes. The Magneto-Telluric method (MT method) is widely used for monitoring the electrical conductivity structure of the Earth. Generally, MT method uses Fourier transform as a spectrum analysis to determine the response function. However, concerning the Fourier transform, the existence of artificial noises sometimes gives a large influence on the analysis, theoretically. Therefore, we used Wavelet Transform instead of the conversional Fourier transform because of the advantage of time-frequency (scale) resolution. Furthermore, we applied the Inter-Transfer Function (ISTF) method to the calculation of the response function (Halada et al. 2004,Phys. Chem. Earth). We used the Morlet wavelet as a mother wavelet for the analysis, which is characterized by a sinusoidal function with a Gaussian window. In this study, we applied above mentioned technique for the data of Nakatatsu mine, Mount Iwate and Kakioka geomagnetic observatory from 1998 to 2002. We have calculated ISTF, apparent resistivity and phase every 3 months interval. At this moment, we can say that clear ISTF changes of 20 % occurred in year 2000 summer. The authors believe ISTF technique is quite useful tool to monitor the crustal activities.

Suto, N.; Harada, M.; Nagao, T.

2005-12-01

250

Cotton Transformation  

Microsoft Academic Search

Cotton has been cultured in vitro for 37 years, yet even today, some of the culture difficulties that were seen when it was\\u000a first cultured, namely, a very long culture time and a limited number of cultivars that can be cultured, continue to pose\\u000a problems. These inherent tissue culture limitations have made transforming cotton an arduous process. Transforming embryogenic\\u000a callus

D. R. Duncan

251

DNA Transformation  

NSDL National Science Digital Library

Stanley Cohen and Herbert Boyer's historic experiment used techniques to cut and paste DNA to create the first custom-made organism containing recombined or 'recombinant' DNA. Cohen and Boyer inserted the recombinant DNA molecule they created into E. coli bacteria by means of a plasmid, thereby inducing the uptake and expression of a foreign DNA sequence known as 'transformation.' This animation from Cold Spring Harbor Laboratory's Dolan DNA Learning Center presents DNA transformation through a series of illustrations of the processes involved.

252

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)

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.

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

2008-05-01

253

Assessment of FLD-based algorithms for the retrieval of vegetation solar-induced fluorescence from the in-filling of the telluric O2-A and O2-B lines  

NASA Astrophysics Data System (ADS)

This study evaluates the performances of different algorithms for the retrieval of solar induced fluorescence of vegetation in both the telluric O2-A and O2-B bands of the atmospheric molecular oxygen, respectively at 760 nm and 687 nm. In particular, we evaluated the performances of three algorithms amongst those already applied by the scientific community: two of them are based on the use of two or three spectral bands (sFLD and 3FLD methods), while the third one exploits the information content of all the spectral channels in certain bands by applying a polynomial model for fluorescence and reflectance (SFM method). These were applied to a synthetic set of fluorescence data corresponding to different types of vegetation. The main technical specifications of the spectroradiometer have been outlined in terms of three different airborne operating scenarios, addressing different flight altitudes and speeds chosen on the basis of typical platforms suitable for operation from low-medium altitudes. The results underline that the high spectral resolution of the instrument plays a fundamental role for the determination of the value of fluorescence with a good precision and accuracy, as expected. Nevertheless, the extraction of the value of fluorescence in the O2-A band is less critical than in the O2-B band and, specifically, it is less sensitive to the spectral resolution of the spectroradiometer. Even at low spectral resolutions, however, the retrieval algorithms based on polynomial fitting provided better results than methods based on the use of spectral bands.

Palombi, Lorenzo; Di Ninni, Paola; Guzzi, Donatella; Lognoli, David; Nardino, Vanni; Pippi, Ivan; Raimondi, Valentina

2013-10-01

254

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

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 muM and 300 muM 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 T(1) progeny could be distinguished from the recessive progeny when grown on 400, 450, or 500 muM 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 Delta(1)-pyrroline-5-carboxylate (P5C). However, H(2)O(2) 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

Tsai, Fei-Yi; Zhang, Xing-Hai; Ulanov, Alexander; Widholm, Jack M

2010-06-01

255

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

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

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

2010-01-01

256

Transformation in fungi.  

PubMed Central

Transformation with exogenous deoxyribonucleic acid (DNA) now appears to be possible with all fungal species, or at least all that can be grown in culture. This field of research is at present dominated by Saccharomyces cerevisiae and two filamentous members of the class Ascomycetes, Aspergillus nidulans and Neurospora crassa, with substantial contributions also from fission yeast (Schizosaccharomyces pombe) and another filamentous member of the class Ascomycetes, Podospora anserina. However, transformation has been demonstrated, and will no doubt be extensively used, in representatives of most of the main fungal classes, including Phycomycetes, Basidiomycetes (the order Agaricales and Ustilago species), and a number of the Fungi Imperfecti. The list includes a number of plant pathogens, and transformation is likely to become important in the analysis of the molecular basis of pathogenicity. Transformation may be maintained either by using an autonomously replicating plasmid as a vehicle for the transforming DNA or through integration of the DNA into the chromosomes. In S. cerevisiae and other yeasts, a variety of autonomously replicating plasmids have been used successfully, some of them designed for use as shuttle vectors for Escherichia coli as well as for yeast transformation. Suitable plasmids are not yet available for use in filamentous fungi, in which stable transformation is dependent on chromosomal integration. In Saccharomyces cerevisiae, integration of transforming DNA is virtually always by homology; in filamentous fungi, in contrast, it occurs just as frequently at nonhomologous (ectopic) chromosomal sites. The main importance of transformation in fungi at present is in connection with gene cloning and the analysis of gene function. The most advanced work is being done with S. cerevisiae, in which the virtual restriction of stable DNA integration to homologous chromosome loci enables gene disruption and gene replacement to be carried out with greater precision and efficiency than is possible in other species that show a high proportion of DNA integration events at nonhomologous (ectopic) sites. With a little more trouble, however, the methodology pioneered for S. cerevisiae can be applied to other fungi too. Transformation of fungi with DNA constructs designed for high gene expression and efficient secretion of gene products appears to have great commercial potential. PMID:2651864

Fincham, J R

1989-01-01

257

Studies on the identification of the heteropoly acid generated in the H 3PO 4–WO 3–Nb 2O 5 catalyst and its thermal transformation process  

Microsoft Academic Search

The precursor of the mixed metal oxide catalyst composed of H3PO4–WO3–Nb2O5, which exhibits excellent activity in Friedel–Crafts alkylations, was identified with 31P NMR. It was revealed that the Keggin-type mixed heteropoly acid, H4PNbW11O40, was spontaneously generated during preparation of the H3PO4–WO3–Nb2O5 catalyst. The partial decomposition of H4PNbW11O40 occurred in the temperature range of 673–823 K to give an amorphous oxide

Kazu Okumura; Katsuhiko Yamashita; Kazuhiro Yamada; Miki Niwa

2007-01-01

258

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

259

SPATIAL TRANSFORMATIONS 1 Running head: Spatial transformations  

E-print Network

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

Zacks, Jeffrey M.

260

Psychoanalytic transformations.  

PubMed

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

Riolo, Fernando

2007-12-01

261

Fourier Transform Pairs The Fourier transform transforms a function of  

E-print Network

Fourier Transform Pairs The Fourier transform transforms a function of time, f(t), into a function of frequency, F(s): F {f(t)}(s) = F(s) = Z - f(t)e- j2st dt. The inverse Fourier transform transforms a func. The inverse Fourier transform of the Fourier trans- form is the identity transform: f(t) = Z - Z - f()e- j2s

Masci, Frank

262

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.  

PubMed

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. PMID:24658808

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

2014-05-01

263

The Laplace Transform 1 Laplace transform and inverse transform  

E-print Network

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

Yengulalp, Lynne

264

Exploring Transformations  

NSDL National Science Digital Library

In this activity, students will explore transformations of an absolute value function. Step by step instructions guide students in using graphing calculators to examine the effect that stretching and translating has on the coordinates of the graph. Teacher notes and a worksheet are also included to aid in teaching this lesson.

2012-08-29

265

Transformation Time  

ERIC Educational Resources Information Center

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"…

Berry, John N., III

2007-01-01

266

Transformation & Metamorphosis  

ERIC Educational Resources Information Center

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…

Lott, Debra

2009-01-01

267

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.

268

RF transformer  

DOEpatents

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

Smith, James L. (Naperville, IL); Helenberg, Harold W. (Calumet City, IL); Kilsdonk, Dennis J. (Joliet, IL)

1979-01-01

269

Transformers Transformer device used to raise (for  

E-print Network

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

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

270

Transformative learning.  

PubMed

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

Nemec, Patricia B

2012-12-01

271

Hamlet's Transformation.  

NASA Astrophysics Data System (ADS)

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

Usher, P. D.

1997-12-01

272

Rotary Transformer  

NASA Technical Reports Server (NTRS)

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

McLyman, Colonel Wm. T.

1996-01-01

273

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

PubMed

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

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

2015-02-01

274

Pantothenic acid biosynthesis in zymomonas  

DOEpatents

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.

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

2014-07-01

275

Testability Transformation: Program Transformation to Improve Testability  

E-print Network

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

Singer, Jeremy

276

Testability Transformation --Program Transformation to Improve Testability  

E-print Network

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

Binkley, David W.

277

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

DOEpatents

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

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

1995-07-04

278

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

DOEpatents

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

Ohlrogge, John B. (Okemos, MI); Cahoon, Edgar B. (Lansing, MI); Shanklin, John (Upton, NY); Somerville, Christopher R. (Okemos, MI)

1995-01-01

279

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

PubMed

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

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

1986-03-01

280

Random fractional Fourier transform.  

PubMed

We propose a novel random fractional Fourier transform by randomizing the transform kernel function of the conventional fractional Fourier transform. The random fractional Fourier transform inherits the excellent mathematical properties from the fractional Fourier transform and can be easily implemented in optics. As a primary application the random fractional Fourier transform can be directly used in optical image encryption and decryption. The double phase encoding image encryption schemes can thus be modeled with cascaded random fractional Fourier transformers. PMID:17671545

Liu, Zhengjun; Liu, Shutian

2007-08-01

281

Quantum transformations  

SciTech Connect

We show that the quantum Hamilton-Jacobi equation can be written in the classical form with the spatial derivative {partial_derivative}{sub q} replaced by {partial_derivative}{sub q} with dq = dq/{radical}1{minus}{beta}{sup 2}(q), where {beta}{sup 2}(q) is strictly related to the quantum potential. This can be seen as the opposite of the problem of finding the wave function representation of classical mechanics as formulated by Schiller and Rosen. The structure of the above {open_quotes}quantum transformation{close_quotes}, related to the recently formulated equivalence principle, indicates that the potential deforms space geometry. In particular, a result by Flanders implies that both W(q) = V(q) {minus} E and the quantum potential Q are proportional to the curvatures {kappa}{sub W} and {kappa}{sub Q} which arise as natural invariants in an equivalence problem for curves in the projective line. In this formulation the Schroedinger equation takes the geometrical form ({partial_derivative}{sub q}{sup 2} + {kappa}{sub W}){psi} = 0.

Faraggi, A.E. [Univ. of Florida, Gainesville, FL (United States). Institute for Fundamental Theory; Matone, M. [Univ. of Padova (Italy). Dept. of Physics G. Galilei

1998-01-09

282

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

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

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

2014-04-01

283

Hadamard transform imaging  

SciTech Connect

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.

Morris, M.D.

1992-01-01

284

Transforming giants.  

PubMed

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

Kanter, Rosabeth Moss

2008-01-01

285

Parameterized Transformation Units  

Microsoft Academic Search

Transformation units are a structuring principle for graph transformation systems. They consist of a set of graph transformation rules, descriptions of initial and terminal graphs, a control condition, and a set of imported transformation units. Semantically, they transform initial graphs to terminal ones by interleaving rule applications with calls to imported units in such a way that the control condition

Sabine Kuske

2002-01-01

286

Analyzing Signals Fourier transform  

E-print Network

Page 1 1 Analyzing Signals Fourier transform s frequency content s linear combination of sin frequency analysis s windowed Fourier transform 6 #12;Page 4 7 Gabor Transform function to analyze window Gabor Transform Spatial domain Gabor domain b #12;Page 5 9 Gabor Transform Problems s discrete version

Sweldens, Wim

287

GIS TRANSFORMATIONS Conference Presentation  

E-print Network

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

Tobler, Waldo

288

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

PubMed

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

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

2010-06-01

289

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

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

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

2000-12-01

290

Transforms in Statistics  

Microsoft Academic Search

It is not an overstatement to say that statistics is based on various transformations of data. Basic statistical summaries such as the sample mean, variance, z-scores, histograms, etc., are all transformed data. Some more advanced summaries, such as principal components, periodograms, empirical characteristic functions, etc., are also examples of transformed data. To give a just coverage of transforms utilized in

Brani Vidakovic

2004-01-01

291

Glowing Bacteria: Transformation Efficiency  

E-print Network

1 Glowing Bacteria: Transformation Efficiency Purpose: To determine how well your E. coli cells took up and expressed GFP after transformation. Background: Transformation efficiency is a quantitative)______ (Fraction of DNA spread on plate) = ______ µg plasmid DNA spread on plate #12;2 5. Transformation efficiency

Rose, Michael R.

292

transformation languages Introduction  

E-print Network

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

Nierstrasz, Oscar

293

RM2: Transform operations  

NASA Technical Reports Server (NTRS)

The two-dimensional transform used in the research TV source encoder, RM2 is discussed. It is shown that both conceptually and in terms of the number of required computations, the RM2 transform is considerably simpler than the Fast Hadamard Transform. The latter can in fact be generated by extending the RM2 transform.

Rice, R. F.

1974-01-01

294

LAPPED TRANSFORMS COMPRESSION  

E-print Network

the basic notation, give a brief history of lapped transforms and introduce block-based transforms. We) vector while A represents a matrix. 6.1.2 Brief history In the early 80's, transform coding was maturing extensively studied mainly because lapped transforms are closely related to filter banks, wavelets, and time

de Queiroz, Ricardo L.

295

Fast Discrete Curvelet Transforms  

Microsoft Academic Search

This paper describes two digital implementations of a new mathematical transform, namely, the second generation curvelet transform (12, 10) in two and three dimensions. The first digital transformation is based on unequally-spaced fast Fourier transforms (USFFT) while the second is based on the wrapping of specially selected Fourier samples. The two implementations essentially dier by the choice of spatial grid

Emmanuel Cande?s; Laurent Demanet; David Donoho; Lexing Ying

2006-01-01

296

Martensitic transformation of Ca  

Microsoft Academic Search

At room temperature Ca undergoes a pressure-induced structural transformation at 20 GPa from the fcc structure into the more open packed bcc. We investigate a distortion model for this transformation that differs from the Bain mechanism usually invoked to describe this transformation and consists of a variant of the Burgers mechanism for the hcp-->bcc transformation. It is shown that the

Renata M. Wentzcovitch; Henry Krakauer

1990-01-01

297

Discrete Cosine Transform  

Microsoft Academic Search

A discrete cosine transform (DCT) is defined and an algorithm to compute it using the fast Fourier transform is developed. It is shown that the discrete cosine transform can be used in the area of digital processing for the purposes of pattern recognition and Wiener filtering. Its performance is compared with that of a class of orthogonal transforms and is

N. Ahmed; T. Natarajan; K. R. Rao

1974-01-01

298

Fatty Acid Engineering 2011 p. 1 Lipid signals: jasmonic acid & green leaf volatiles  

E-print Network

to prime other inducible defense #12;Fatty Acid Engineering 2011 p. 2 Fatty Acids and Genetic EngineeringFatty Acid Engineering 2011 p. 1 Lipid signals: jasmonic acid & green leaf volatiles i. Jasmonic occurrence of modified 'specialty' FAs - genetic transformation technology available (NB: oil seeds amenable

Constabel, Peter

299

Perfect NOT transformation and conjugate transformation  

E-print Network

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.

Fengli Yan; Ting Gao; Zhichao Yan

2012-03-15

300

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

NASA Astrophysics Data System (ADS)

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.

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

2010-02-01

301

Transformation of Haemophilus influenzae by plasmid RSF0885.  

PubMed

Plasmid RSF0885, which conferred ampicillin resistance, transformed competent Haemophilus influenzae cells with low efficiency (maximum, less than 0.01%). As judged by competition experiments and uptake of radioactivity, plasmid RSF0885 deoxyribonucleic acid was taken up into competent H. influenzae cells several orders of magnitude less efficiently than H. influenzae chromosomal deoxyribonucleic acid. Plasmid RSF0885 transformed cells with even lower efficiency than could be accounted for by the low uptake. Transformation was not affected by rec-1 and rec-2 mutations in the recipient, and strains cured of the plasmid did not show increased transformation. Plasmid molecules cut once with a restriction enzyme that made blunt ends did not transform. Transformation was favored by the closed circular form of the plasmid. PMID:6975775

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

1981-12-01

302

Boswellic acid inhibits expression of acid sphingomyelinase in intestinal cells  

PubMed Central

Background Boswellic acid is a type of triterpenoids with antiinflammatory and antiproliferative properties. Sphingomyelin metabolism generates multiple lipid signals affecting cell proliferation, inflammation, and apoptosis. Upregulation of acid sphingomyelinase (SMase) has been found in several inflammation-related diseases such as inflammatory bowel diseases, atherosclerosis, and diabetes. Methods The present study is to examine the effect of 3-acetyl-11-keto-?-boswellic acids (AKBA), a potent boswellic acid, on acid SMase activity and expression in intestinal cells. Both transformed Caco-2 cells and non-transformed Int407 cells were incubated with AKBA. After incubation, the change of acid SMase activity was assayed biochemically, the enzyme protein was examined by Western blot, and acid SMase mRNA was quantified by qPCR. Results We found that AKBA decreased acid SMase activity in both intestinal cell lines in dose and time dependent manners without affecting the secretion of the enzyme to the cell culture medium. The effect of AKBA was more effective in the fetal bovine serum-free culture medium. Among different types of boswellic acid, AKBA was the most potent one. The inhibitory effect on acid SMase activity occurred only in the intact cells but not in cell-free extract in the test tubes. At low concentration, AKBA only decreased the acid SMase activity but not the quantity of the enzyme protein. However, at high concentration, AKBA decreased both the mass of acid SMase protein and the mRNA levels of acid SMase in the cells, as demonstrated by Western blot and qPCR, respectively. Under the concentrations decreasing acid SMase activity, AKBA significantly inhibited cell proliferation. Conclusion We identified a novel inhibitory effect of boswellic acids on acid SMase expression, which may have implications in human diseases and health. PMID:19951413

2009-01-01

303

Landscapes of transformation  

E-print Network

This thesis aims to examine the cultural effect of transformation through the lens of procedural techniques applied to the human body and architecture. The body and architecture both operate as landscapes of transformation. ...

Ambs, Emily (Emily Kiersten)

2007-01-01

304

Metrics for enterprise transformation  

E-print Network

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, ...

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

2009-01-01

305

Equations For Rotary Transformers  

NASA Technical Reports Server (NTRS)

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

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

1988-01-01

306

28-Channel rotary transformer  

NASA Technical Reports Server (NTRS)

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

Mclyman, W. T.

1981-01-01

307

Probabilistically Accurate Program Transformations  

E-print Network

The standard approach to program transformation involves the use of discrete logical reasoning to prove that the transformation does not change the observable semantics of the program. We propose a new approach that, in ...

Misailovic, Sasa

308

Amino acids  

MedlinePLUS

Amino acids are organic compounds that combine to form proteins . Amino acids and proteins are the building blocks of life. When proteins are digested or broken down, amino acids are left. The human body uses amino acids ...

309

DNA Transformation, Continued  

NSDL National Science Digital Library

DNA transformation is a naturally occurring but rare event in which DNA can be transferred into bacteria. In 1970, Morton Mandel and Akiko Higa discovered a way to make E. coli more 'competent' for transforming foreign DNA. Their calcium chloride method is widely used today to obtain high-efficiency transforming cells. This animation from Cold Spring Harbor Laboratory's Dolan DNA Learning Center presents the second part of explaining DNA transformation through a series of illustrations of the processes involved.

310

Transforming Anxiety into ENERGYTM  

E-print Network

Transforming Anxiety into ENERGYTM How to Prevent Panic and Promote Productivity in Turbulent Times By Wendy Mack with contributions from Meredith Kimbell and Myron Radio #12;Transforming Anxiety into Energy, consultants, and researchers who shared their stories and expertise. 1 #12;Transforming Anxiety into Energy

Maryland, Baltimore County, University of

311

Transformations - Composition (NLVM)  

NSDL National Science Digital Library

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.

2011-01-01

312

Robust Singular Spectrum Transform  

Microsoft Academic Search

Change Point Discovery is a basic algorithm needed in many time series mining applications including rule discovery, motif discovery, casual analysis, etc. Several techniques for change point discovery have been suggested including wavelet analysis, cosine transforms, CUMSUM, and Singular Spectrum Transform. Of these methods Singular Spectrum Transform (SST) have received much attention because of its generality and because it does

Yasser F. O. Mohammad; Toyoaki Nishida

2009-01-01

313

Spacetime transformation acoustics  

E-print Network

A recently proposed analogue transformation method has allowed the extension of transformation acoustics to general spacetime transformations. We analyze here in detail the differences between this new analogue transformation acoustics (ATA) method and the standard one (STA). We show explicitly that STA is not suitable for transformations that mix space and time. ATA takes as starting point the acoustic equation for the velocity potential, instead of that for the pressure as in STA. This velocity-potential equation by itself already allows for some transformations mixing space and time, but not all of them. We explicitly obtain the entire set of transformations that do not leave its form invariant. It is in these cases that ATA shows its true potential, allowing for building a transformation acoustics method that enables the full range of spacetime transformations. We provide an example of an important transformation which cannot be achieved with STA. Using this transformation, we design and simulate an acoustic frequency converter via the ATA approach. Furthermore, in those cases in which one can apply both the STA and ATA approaches, we study the different transformational properties of the corresponding physical quantities.

C. García-Meca; S. Carloni; C. Barceló; G. Jannes; J. Sánchez-Dehesa; A. Martínez

2014-07-08

314

Uniform discrete curvelet transform  

Microsoft Academic Search

An implementation of the discrete curvelet transform is proposed in this work. The transform is based on and has the same order of complexity as the Fast Fourier Transform (FFT). The discrete curvelet functions are defined by a parameterized family of smooth windowed functions that satisfies two conditions: i) 2? periodic; ii) their squares form a partition of unity. The

Truong T. Nguyen; Hervé Chauris

2010-01-01

315

Resonance transformer power conditioners  

Microsoft Academic Search

Designs for power conditioning systems based on the resonance transformer have been developed for applications requiring compact, lightweight power supplies ranging from average power levels of 10 kW to over 1 MW. The resonance transformer is a patented concept which depends on a set of resonant LC circuits to produce transformer-like voltage or current gain. Because this approach does not

R. M. Ness; S. G. E. Pronko; J. R. Cooper; E. Y. Chu

1990-01-01

316

Enabling transformation with TSAT  

Microsoft Academic Search

The transformational satellite communications system (TSAT) is one component of the global information grid (GIG) that will enable transformation to support the warfighting efforts for the United States of America and its allies. To support transformation, TSAT will be fully integrated with the standards developed for the GIG. This paper provides an overview of the challenges and approaches into this

D. M. Stround; Phong Pham Tran

2005-01-01

317

Efficient Quantum Transforms  

E-print Network

Quantum mechanics requires the operation of quantum computers to be unitary, and thus makes it important to have general techniques for developing fast quantum algorithms for computing unitary transforms. A quantum routine for computing a generalized Kronecker product is given. Applications include re-development of the networks for computing the Walsh-Hadamard and the quantum Fourier transform. New networks for two wavelet transforms are given. Quantum computation of Fourier transforms for non-Abelian groups is defined. A slightly relaxed definition is shown to simplify the analysis and the networks that computes the transforms. Efficient networks for computing such transforms for a class of metacyclic groups are introduced. A novel network for computing a Fourier transform for a group used in quantum error-correction is also given.

Peter Hoyer

1997-02-12

318

Mutant fatty acid desaturase  

DOEpatents

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

Shanklin, John; Cahoon, Edgar B.

2004-02-03

319

The Conversion of Carboxylic Acids to Ketones: A Repeated Discovery  

ERIC Educational Resources Information Center

The conversion of carboxylic acids to ketones is a useful chemical transformation with a long history. Several chemists have claimed that they discovered the conversion of carboxylic acids to ketones yet in fact the reaction is actually known for centuries.

Nicholson, John W.; Wilson, Alan D.

2004-01-01

320

A FURTHER EVALUATION OF MICROCOULOMETRY FOR ATMOSPHERIC NITRIC ACID MONITORING  

EPA Science Inventory

A coulometric instrument for measuring gaseous nitric acid is modified to improve response time characteristics and simplify operation. Possible interferences were investigated and found minimal. Comparison measurements of nitric acid by long path Fourier Transform infrared analy...

321

Continuous curvelet transform  

Microsoft Academic Search

We discuss a Continuous Curvelet Transform (CCT), a transform f??f(a,b,?) of functions f(x1,x2) on R2 into a transform domain with continuous scale a>0, location b?R2, and orientation ??[0,2?). Here ?f(a,b,?)=?f,?ab?? projects f onto analyzing elements called curvelets?ab? which are smooth and of rapid decay away from an a by a rectangle with minor axis pointing in direction ?. We call

Emmanuel J. Candès; David L. Donoho

2005-01-01

322

Semantics of Database Transformations  

Microsoft Academic Search

. Database transformations arise in many different settings includingdatabase integration, evolution of database systems, and implementing user viewsand data-entry tools. This paper surveys approaches that have been taken to problemsin these settings, assesses their strengths and weaknesses, and develops requirementson a formal model for specifying and implementing database transformations.We also consider the problem of insuring the correctness of database transformations.In

Peter Buneman; Susan B. Davidson; Anthony Kosky

1995-01-01

323

Magnetically Controlled Variable Transformer  

NASA Technical Reports Server (NTRS)

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

Kleiner, Charles T.

1994-01-01

324

Amplified quantum transforms  

NASA Astrophysics Data System (ADS)

In this thesis we investigate two new Amplified Quantum Transforms. In particular we create and analyze the Amplified Quantum Fourier Transform (Amplified-QFT) and the Amplified-Haar Wavelet Transform. The Amplified-QFT algorithm is used to solve the Local Period Problem. We calculate the probabilities of success and compare this algorithm with the QFT and QHS algorithms. We also examine the Amplified-QFT algorithm for solving the Local Period Problem with Error Stream. We use the Amplified-Haar Wavelet Transform for solving the Local Constant or Balanced Signal Decision Problem which is a generalization of the Deutsch-Jozsa problem.

Cornwell, David J.

325

Folic Acid  

MedlinePLUS

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

326

Folic Acid  

MedlinePLUS

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

327

Biotransformation of linoleic acid by Clavibacter sp. ALA2: Heterocyclic and heterobicyclic fatty acids  

Microsoft Academic Search

Clavibacter sp. ALA2 transformed linoleic acid into a variety of oxylipins. In previous work, three novel fatty acids were identified,\\u000a (9Z)-12,13,17-trihydroxy-9-octadecenoic acid and two tetrahydrofuran-(di)hydroxy fatty acids. In this report, we confirm the\\u000a structures of the tetrahydrofuran-(di)hydroxy fatty acids by nuclear magnetic resonance as (9Z)-12-hydroxy-13,16-epoxy-9-octadecenoic acid and (9Z)-7,12-dihydroxy-13,16-epoxy-9-octadecenoic acid. Three other products of the biotransformation were identified as novel heterobicyclic

Harold W. Gardner; Ching T. Hou; David Weisleder; Wanda Brown

2000-01-01

328

Growth of nitric acid hydrates on thin sulfuric acid films  

NASA Technical Reports Server (NTRS)

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.

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

1994-01-01

329

Power transformer testing  

NASA Astrophysics Data System (ADS)

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.

Zagrobelna, Magdalena; Wasilewski, Andrzej

2014-11-01

330

Facile transformation of Arabidopsis  

Microsoft Academic Search

A protocol is described for the simple, rapid and efficient production of transgenic Arabidopsis plants. The procedure was developed using growth regulator regimes that promote adventitious embryogenesis during or immediately following Agrobacterium mediated transformation. Both the RLD and Columbia genotypes of Arabidopsis were transformed using slightly different growth regulator regimes. For the Columbia genotype two modifications of the protocol were

László Márton; John Browse

1991-01-01

331

Direct current transformer  

NASA Technical Reports Server (NTRS)

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.

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

1979-01-01

332

Transformer design tradeoffs  

NASA Technical Reports Server (NTRS)

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

Mclyman, W. T.

1977-01-01

333

Genetic Transformation of Bacteria.  

ERIC Educational Resources Information Center

An activity in which students transform an ampicillin-sensitive strain of E. coli with a plasmid containing a gene for ampicillin resistance is described. The procedure for the preparation of competent cells and the transformation of competent E. coli is provided. (KR)

Moss, Robert.

1991-01-01

334

Exploring Functional Mellin Transforms  

E-print Network

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.

J. LaChapelle

2015-01-08

335

Shiftable multiscale transforms  

Microsoft Academic Search

Orthogonal wavelet transforms have recently become a popular representation for multiscalesignal and image analysis. One of the major drawbacks of these representations istheir lack of translation invariance: the content of wavelet subbands is unstable under translationsof the input signal. Wavelet transforms are also unstable with respect to dilationsof the input signal, and in two dimensions, rotations of the input signal.

Eero P. Simoncelli; William T. Freeman; Edward H. Adelson; David J. Heeger

1992-01-01

336

Conformal transformation optics  

NASA Astrophysics Data System (ADS)

The field of transformation optics shows that media containing gradients in optical properties are equivalent to curved geometries of spacetime for the propagation of light. Conformal transformation optics -- a particular variant of this feature -- can be used to design devices with novel functionalities from inhomogeneous, isotropic dielectric media.

Xu, Lin; Chen, Huanyang

2015-01-01

337

Complex rectangular transforms  

Microsoft Academic Search

While deriving rectangular transforms Agarwal and cooley have used polynomial factors with real integer coefficients which resulted in real convolution matrices. In this paper, it is shown that the use of polynomial factors with complex integer coefficients yields new algorithms with complex convolution matrices, which require less number of multiplications than rectangular transforms. The paper outlines the derivation of the

V. Reddy; N. Reddy

1979-01-01

338

Biochemical transformation of coals  

DOEpatents

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.

Lin, Mow S. (Rocky Point, NY); Premuzic, Eugene T. (East Moriches, NY)

1999-03-23

339

Transforming the supply chain  

Microsoft Academic Search

Purpose – Today's business environment emerges the need for organizations to continuously transform themselves, in order to maintain and reinforce their ability to compete successfully. The purpose of this paper is to present an analysis of the transformation process of supply chain in order to provide a modular structured management tool for planning, implementing and measure the effectiveness of supply

Evangelia D. Fassoula

2006-01-01

340

Biochemical transformation of coals  

DOEpatents

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.

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

1999-03-23

341

Deployment & Market Transformation (Brochure)  

SciTech Connect

NREL's deployment and market transformation (D and MT) activities encompass the laboratory's full range of technologies, which span the energy efficiency and renewable energy spectrum. NREL staff educates partners on how they can advance sustainable energy applications and also provides clients with best practices for reducing barriers to innovation and market transformation.

Not Available

2012-04-01

342

Support Principals, Transform Schools  

ERIC Educational Resources Information Center

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

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

2011-01-01

343

Transforming Dentistry through Innovation  

E-print Network

7 Transforming Dentistry through Innovation and Imagination Research Matters Faculty Highlights's practitioners and researchers through... DentistryF A C U L T Y O F TRANSFORMING DENTISTRY THROUGH INNOVATION a short time ago, were not possible. Naturally, these changes are influencing the teaching of dentistry

Barthelat, Francois

344

The Curvelet Transform  

Microsoft Academic Search

Multiresolution methods are deeply related to image processing, biological and computer vision, and scientific computing. The curvelet transform is a multiscale directional transform that allows an almost optimal nonadaptive sparse representation of objects with edges. It has generated increasing interest in the community of applied mathematics and signal processing over the years. In this article, we present a review on

Jianwei Ma; Gerlind Plonka

2010-01-01

345

Transformations in Milton's "Comus"  

E-print Network

of interventi. on by a deity. Thus, in Rook VIII, Minerva transforms Icarus into a partridge; in Hook X, Venus changes Adonis into an anemone; i. n Rook XV, Diana changes Zgcria into a tree. However, transforms. tion may be within +he cl"aracter's own power...

Yu, Hung-Chih

1969-01-01

346

Martensitic transformation of Ca  

NASA Astrophysics Data System (ADS)

At room temperature Ca undergoes a pressure-induced structural transformation at 20 GPa from the fcc structure into the more open packed bcc. We investigate a distortion model for this transformation that differs from the Bain mechanism usually invoked to describe this transformation and consists of a variant of the Burgers mechanism for the hcp-->bcc transformation. It is shown that the Bain mechanism is a specific case of this more general triclinic distortion, and therefore that a path in this larger parameter space provides a different energy route when compared with that derived from the tetragonal Bain strain, which is lower in energy at some points. This finding is particularly relevant for future studies of temperature-induced fcc-->bcc transformations. Our first-principles total-energy local-density-approximation study is accomplished by using the full-potential linear-augmented-plane-wave method.

Wentzcovitch, Renata M.; Krakauer, Henry

1990-09-01

347

Logarithmic transformation of response Logarithmic transformation of response  

E-print Network

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

Komarek, Arnost

348

Program Transformation Mechanics A Classification of Mechanisms for Program Transformation  

E-print Network

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

Utrecht, Universiteit

349

IMAGINED TRANSFORMATIONS 1 Running head: IMAGINED TRANSFORMATION OF BODIES  

E-print Network

IMAGINED TRANSFORMATIONS 1 Running head: IMAGINED TRANSFORMATION OF BODIES Imagined Transformations TRANSFORMATIONS 2 Abstract A number of spatial reasoning problems can be solved by performing an imagined transformation of one's egocentric perspective. A series of experiments were carried out to characterize

Zacks, Jeffrey M.

350

Genetic transformation of green-colored cotton  

Microsoft Academic Search

Summary  This study reports an Agrobacterium-mediated transformation of green-colored cotton (Gossypium hirsutum L.). A tissue culture procedure was optimized to induce callus formation from hypocotyl explants and subsequent differentiation\\u000a into the embryogenic type. Callus formation could be induced by growing explants on Murashige and Skoog medium containing\\u000a 2,4-dichlorophenoxyacetic acid and kinetin. Among the four genotypes studied, embryogenic calli and plant regeneration

Sheng-Wei Zhu; Peng Gao; Jing-San Sun; Hai-Hua Wang; Xiao-Min Luo; Ming-Yu Jiao; Zhi-Yong Wang; Gui-Xian Xia

2006-01-01

351

Transformation of gram positive bacteria by sonoporation  

SciTech Connect

The present invention provides a sonoporation-based method that can be universally applied for delivery of compounds into Gram positive bacteria. Gram positive bacteria which can be transformed by sonoporation include, for example, Bacillus, Streptococcus, Acetobacterium, and Clostridium. Compounds which can be delivered into Gram positive bacteria via sonoporation include nucleic acids (DNA or RNA), proteins, lipids, carbohydrates, viruses, small organic and inorganic molecules, and nano-particles.

Yang, Yunfeng; Li, Yongchao

2014-03-11

352

Pattern transformation with DNA circuits.  

PubMed

Readily programmable chemical networks are important tools as the scope of chemistry expands from individual molecules to larger molecular systems. Although many complex systems are 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 designed and implemented non-enzymatic DNA circuits capable of performing pattern-transformation algorithms such as edge detection. We also showed that it is possible to fine-tune and multiplex such circuits. We believe these strategies will provide programmable platforms on which to prototype CRNs, discover bottom-up construction principles and generate patterns in materials. PMID:24256862

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

2013-12-01

353

Pattern transformation with DNA circuits  

NASA Astrophysics Data System (ADS)

Readily programmable chemical networks are important tools as the scope of chemistry expands from individual molecules to larger molecular systems. Although many complex systems are 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 designed and implemented non-enzymatic DNA circuits capable of performing pattern-transformation algorithms such as edge detection. We also showed that it is possible to fine-tune and multiplex such circuits. We believe these strategies will provide programmable platforms on which to prototype CRNs, discover bottom-up construction principles and generate patterns in materials.

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

2013-12-01

354

Pattern Transformation with DNA Circuits  

PubMed Central

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

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

2014-01-01

355

Strongly Acidic Auxin Indole-3-Methanesulfonic Acid  

PubMed Central

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

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

1985-01-01

356

Aspartic acid  

MedlinePLUS

... don't get this amino acid from the food we eat. Aspartic acid is also called asparaginic acid. Aspartic acid helps every cell in the body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources ...

357

Acid Rain.  

ERIC Educational Resources Information Center

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)

Openshaw, Peter

1987-01-01

358

Polystyrene sulphonic acid resins with enhanced acid strength via macromolecular self-assembly within confined nanospace  

NASA Astrophysics Data System (ADS)

Tightening environmental legislation is driving the chemical industries to develop efficient solid acid catalysts to replace conventional mineral acids. Polystyrene sulphonic acid resins, as some of the most important solid acid catalysts, have been widely studied. However, the influence of the morphology on their acid strength—closely related to the catalytic activity—has seldom been reported. Herein, we demonstrate that the acid strength of polystyrene sulphonic acid resins can be adjusted through their reversible morphology transformation from aggregated to swelling state, mainly driven by the formation and breakage of hydrogen bond interactions among adjacent sulphonic acid groups within the confined nanospace of hollow silica nanospheres. The hybrid solid acid catalyst demonstrates high activity and selectivity in a series of important acid-catalysed reactions. This may offer an efficient strategy to fabricate hybrid solid acid catalysts for green chemical processes.

Zhang, Xiaomin; Zhao, Yaopeng; Xu, Shutao; Yang, Yan; Liu, Jia; Wei, Yingxu; Yang, Qihua

2014-01-01

359

Transformer Abdullah Al-Otaibi  

E-print Network

Transformer Abdullah Al-Otaibi ID#242374 Section#2 Abstract- this is a brief description for transformer and how it works. I. DEFINITION A transformer is a device that transfers electrical energy from of the transformer in 1831. The transformer is used by Faraday only to demonstrate the principle of electromagnetic

Masoudi, Husain M.

360

A discrete fractional random transform  

E-print Network

We propose a discrete fractional random transform based on a generalization of the discrete fractional Fourier transform with an intrinsic randomness. Such discrete fractional random transform inheres excellent mathematical properties of the fractional Fourier transform along with some fantastic features of its own. As a primary application, the discrete fractional random transform has been used for image encryption and decryption.

Zhengjun Liu; Haifa Zhao; Shutian Liu

2006-05-20

361

The Practice of Transformative Pedagogy  

ERIC Educational Resources Information Center

The author examined the practice of transformative pedagogy in an undergraduate teacher education program. The research was guided by two questions: What is the impact of transformative pedagogy on fostering preservice teachers' transformative learning? and What practices of transformative pedagogy impact student transformative learning?…

Ukpokodu, Omiunota

2009-01-01

362

p53 domains: structure, oligomerization, and transformation.  

PubMed

Wild-type p53 forms tetramers and multiples of tetramers. Friedman et al. (P. N. Friedman, X. B. Chen, J. Bargonetti, and C. Prives, Proc. Natl. Acad. Sci. USA 90:3319-3323, 1993) have reported that human p53 behaves as a larger molecule during gel filtration than it does during sucrose gradient sedimentation. These differences argue that wild-type p53 has a nonglobular shape. To identify structural and oligomerization domains in p53, we have investigated the physical properties of purified segments of p53. The central, specific DNA-binding domain within murine amino acids 80 to 320 and human amino acids 83 to 323 behaves predominantly as monomers during analysis by sedimentation, gel filtration, and gel electrophoresis. This consistent behavior argues that the central region of p53 is globular in shape. Under appropriate conditions, however, this segment can form transient oligomers without apparent preference for a single oligomeric structure. This region does not enhance transformation by other oncogenes. The biological implications of transient oligomerization by this central segment, therefore, remain to be demonstrated. Like wild-type p53, the C terminus, consisting of murine amino acids 280 to 390 and human amino acids 283 to 393, behaves anomalously during gel filtration and apparently has a nonglobular shape. Within this region, murine amino acids 315 to 350 and human amino acids 323 to 355 are sufficient for assembly of stable tetramers. The finding that murine amino acids 315 to 360 enhance transformation by other oncogenes strongly supports the role of p53 tetramerization in oncogenesis. Amino acids 330 to 390 of murine p53 and amino acids 340 to 393 of human p53, which have been implicated by Sturzbecher et al. in tetramerization (H.-W. Sturzbecher, R. Brain, C. Addison, K. Rudge, M. Remm, M. Grimaldi, E. Keenan, and J. R. Jenkins, Oncogene 7:1513-1523, 1992), do not form stable tetramers under our conditions. Our findings indicate that p53 has at least two autonomous oligomerization domains: a strong tetramerization domain in its C-terminal region and a weaker oligomerization domain in the central DNA binding region of p53. Together, these domains account for the formation of tetramers and multiples of tetramers by wild-type p53. The tetramerization domain is the major determinant of the dominant negative phenotype leading to transformation by mutant p53s. PMID:8035799

Wang, P; Reed, M; Wang, Y; Mayr, G; Stenger, J E; Anderson, M E; Schwedes, J F; Tegtmeyer, P

1994-08-01

363

Overview of transformer platform showing three original stepup transformer (center), ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Overview of transformer platform showing three original step-up transformer (center), steel switchback (right), and modern step-down transformer (foreground), view to northwest - Morony Hydroelectric Facility, Dam and Powerhouse, Morony Dam Road, Great Falls, Cascade County, MT

364

Lorentz transformation by mimicking the Lorentz transformation  

E-print Network

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.

Bernhard Rothenstein; Stefan Popescu

2007-09-24

365

Lapped transforms for efficient transform\\/subband coding  

Microsoft Academic Search

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

H. S. Malvar

1990-01-01

366

Transformer design tradeoffs  

NASA Technical Reports Server (NTRS)

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.

Mclyman, W. T.

1976-01-01

367

Biolistics Transformation of Wheat  

NASA Astrophysics Data System (ADS)

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).

Sparks, Caroline A.; Jones, Huw D.

368

Glucuronic acid conjugates of bilirubin-IXalpha in normal bile compared with post-obstructive bile. Transformation of the 1-O-acylglucuronide into 2-, 3-, and 4-O-acylglucuronides.  

PubMed

Structures have been determined for bilirubin-IXalpha conjugates in freshly collected bile of normal rats, dogs and man and in post-obstructive bile of man and rats. The originally secreted conjugate has been characterized as azopigment (I), i.e. a 1-O-acyl-beta-d-glucopyranuronic acid glycoside. Conversion of the acetylated methyl ester of azopigment (I) into methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-beta-d-glucopyranuronate (V) indicates the pyranose ring structure for the carbohydrate and a C-1 attachment for the bilirubin-IXalpha acyl group. Alternative procedures for deconjugation of azopigment (I) and its derivatives are also described. In post-obstructive bile, the 1-O-acylglucuronide is converted into 2-, 3- and 4-O-acylglucuronides via sequential intramolecular migrations of the bilirubin acyl group. The following approach was utilized. (1) The tetrapyrrole conjugates were cleaved to dipyrrolic aniline and ethyl anthranilate azopigments, and the azopigments were separated as the acids or methyl esters. (2) The isomeric methyl esters were characterized by mass spectral analysis of the acetates and silyl ethers. (3) The free glycosidic function was demonstrated by 1-oxime and 1-methoxime derivative formation. (4) The position of the dipyrrolic O-acyl group was determined for the methyl esters by protecting the free hydroxyl groups of the glucuronic acid moieties as the acetals formed with ethyl vinyl ether and by further conversion of the carbohydrates into partially methylated alditol acetates. These were analysed by using g.l.c.-mass spectrometry. The relevance of the present results with regard to previous reports on disaccharidic conjugates is discussed. Details of procedures for the formation of chemical derivatives for g.l.c. and mass spectrometry have been deposited as Supplementary Publication SUP 50081 (15 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978), 169, 5. PMID:646816

Compernolle, F; Van Hees, G P; Blanckaert, N; Heirwegh, K P

1978-04-01

369

Glucuronic acid conjugates of bilirubin-IX? in normal bile compared with post-obstructive bile. Transformation of the 1-O-acylglucuronide into 2-, 3-, and 4-O-acylglucuronides  

PubMed Central

Structures have been determined for bilirubin-IX? conjugates in freshly collected bile of normal rats, dogs and man and in post-obstructive bile of man and rats. The originally secreted conjugate has been characterized as azopigment (I), i.e. a 1-O-acyl-?-d-glucopyranuronic acid glycoside. Conversion of the acetylated methyl ester of azopigment (I) into methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-?-d-glucopyranuronate (V) indicates the pyranose ring structure for the carbohydrate and a C-1 attachment for the bilirubin-IX? acyl group. Alternative procedures for deconjugation of azopigment (I) and its derivatives are also described. In post-obstructive bile, the 1-O-acylglucuronide is converted into 2-, 3- and 4-O-acylglucuronides via sequential intramolecular migrations of the bilirubin acyl group. The following approach was utilized. (1) The tetrapyrrole conjugates were cleaved to dipyrrolic aniline and ethyl anthranilate azopigments, and the azopigments were separated as the acids or methyl esters. (2) The isomeric methyl esters were characterized by mass spectral analysis of the acetates and silyl ethers. (3) The free glycosidic function was demonstrated by 1-oxime and 1-methoxime derivative formation. (4) The position of the dipyrrolic O-acyl group was determined for the methyl esters by protecting the free hydroxyl groups of the glucuronic acid moieties as the acetals formed with ethyl vinyl ether and by further conversion of the carbohydrates into partially methylated alditol acetates. These were analysed by using g.l.c.–mass spectrometry. The relevance of the present results with regard to previous reports on disaccharidic conjugates is discussed. Details of procedures for the formation of chemical derivatives for g.l.c. and mass spectrometry have been deposited as Supplementary Publication SUP 50081 (15 pages) at the British Library Lending Division, Boston Spa, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1978), 169, 5. PMID:646816

Compernolle, Frans; Van Hees, Gustaaf P.; Blanckaert, Norbert; Heirwegh, Karel P. M.

1978-01-01

370

Acidity in bile acid systems  

Microsoft Academic Search

The acidity parameter in bile acid systems was re-examined in an attempt to unify the many contrasting results reported in the literature. Discrepancies originate not only through differences in experimental approaches but mainly through the peculiar behaviour of bile acids and their salts, which can be present in aqueous solution as monomers, or simple and\\/or mixed aggregates. The acidity (and

Adamo Fini; Giorgio Feroci; Aldo Roda

2002-01-01

371

25. VIEW, LOOKING SOUTHWEST INSIDE TRANSFORMER ROOM, SHOWING TRANSFORMERS AND ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

25. VIEW, LOOKING SOUTHWEST INSIDE TRANSFORMER ROOM, SHOWING TRANSFORMERS AND KNIFE SWITCHES - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

372

Synthesis and acid-catalyzed transformations of 1-(1,6,6-trimethylbicyclo(2. 1. 1)hex-5-yl)-1-alkanones and 1-(1,6,6-trimethylbicyclo-(2. 1. 1)hex-5-yl)-1-alken-1-ones  

SciTech Connect

The reaction of 1,6,6-trimethylbicyclo(2.1.1)hexane-5-carbaldehyde (photocitral B) with Grignard reagents followed by oxidation of the obtained alcohols gave 1-(1,6,6-trimethylbicyclo(2.1.1)hex-5-yl)-1-alkanones and 1-(1,6,6-trimethylbicyclo(2.1.1)hex-5-yl)-1-alken-1-ones, which isomerize to 1-(2,3,3-trimethyl-1-cyclopentenyl)-2-alkanones when heated in the presence of p-toluenesulfonic acid. It was shown that the intermediate compounds in this reaction are 1-(2,2,3-trimethyl-3-cyclopentenyl)-2-alkanones. Underanalogous conditions photocitral B isomerizes to /alpha/-campholenaldehyde.

Volkova, O.O.; Cherkaev, G.V.; Novikov, N.A.; Erman, M.B.; Aul'chenko, I.S.; Mochalin, V.B.

1988-06-20

373

Relativistic Transformation of Solid Angle.  

ERIC Educational Resources Information Center

Rederives the relativistic transformations of light intensity from compact sources (stars) to show where and how the transformation of a solid angle contributes. Discusses astrophysical and other applications of the transformations. (Author/CS)

McKinley, John M.

1980-01-01

374

Transforming California's Freight Transport System  

E-print Network

Transforming California's Freight Transport System Policy Forum on the Role of Freight Transport Standard #12;2050 Vision- Key Conceptual Outcomes Technology Transformation Early Action Cleaner Combustion Multiple Strategies Federal Action Efficiency Gains Energy Transformation 9 #12;Further reduce localized

California at Davis, University of

375

Fourier Transform Infrared (FTIR) Spectroscopy  

E-print Network

Fourier Transform Infrared (FTIR) Spectroscopy Klaus Gerwert, Lehrstuhl fu¨r Biophysik, Ruhr Transform IR by Johannes Orphal. Fourier transform infrared (FTIR) spectroscopy is an experimental technique information on molecular structure, chemical bondingandmolecularenvironment.Formanyyears,FTIR has been

Gerwert, Klaus

376

Plant improvement Investigations on transforming  

E-print Network

Plant improvement Investigations on transforming Triticum aestivum via the pollen tube pathway N the necessary conditions to transform wheat Triticum aestivum using the pollen tube pathway. Three methods. Triticum aestivum = wheat / transformation / pollen / nuclease Résumé — Recherches sur la

Paris-Sud XI, Université de

377

5-epideoxyloganic acid from Nepeta cataria.  

PubMed

On the basis of exhaustive (1)H- and (13)C-NMR spectral studies and chemical transformations, the structure of nepetolglucosylester isolated from Nepeta cataria L. was revised as (5R, 8S, 9R)-7-deoxyloganic acid, which was renamed 5-epideoxyloganic acid. PMID:17405103

Tagawa, M; Murai, F

1983-02-01

378

Fourier transform mass spectrometry.  

PubMed

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

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

2011-07-01

379

Fractals and Transformations.  

ERIC Educational Resources Information Center

Discussed are several different transformations based on the generation of fractals including self-similar designs, the chaos game, the koch curve, and the Sierpinski Triangle. Three computer programs which illustrate these concepts are provided. (CW)

Bannon, Thomas J.

1991-01-01

380

Transformer design tradeoffs  

NASA Technical Reports Server (NTRS)

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.

Mclyman, W. T.

1977-01-01

381

Applying Improved Efficiency Transformers  

E-print Network

Today's business and energy conscious environment affords both producers and consumers of electric energy an opportunity to reduce costs and conserve energy through the use of improved efficiency transformers. Various design techniques...

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

382

The Quantum Mellin transform  

E-print Network

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.

J. Twamley; G. J. Milburn

2007-02-12

383

Transformation inverse design  

E-print Network

We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is ...

Liu, David

384

Improved Transformation of Anthurium  

Technology Transfer Automated Retrieval System (TEKTRAN)

Methods to increase transformation efficiency and yields of transgenic Anthurium andraeanum Linden ex. André hybrids were sought while effecting gene transfer for resistance to the two most important pests, bacterial blight (Xanthomonas axonopodis pv. dieffenbachiae) and nematodes (Radopholus simili...

385

Series Transmission Line Transformer  

DOEpatents

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.

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

2004-06-29

386

Functional Mellin Transforms  

E-print Network

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.

J. LaChapelle

2015-01-07

387

Plant transformation technology  

Microsoft Academic Search

Plant transformation has its roots in the research on Agrobacterium that was being undertaken in the early 1980s. The last two decades have seen significant developments in plant transformation\\u000a technology, such that a large number of transgenic crop plants have now been released for commercial production. Advances\\u000a in the technology have been due to development of a range of Agrobacterium-mediated

Christine A. Newell

2000-01-01

388

Selection of Transformed Plants  

NASA Astrophysics Data System (ADS)

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.

Jones, Huw D.; Sparks, Caroline A.

389

Transforming Undergraduate Science Education  

NASA Astrophysics Data System (ADS)

I'll describe: (1) how efforts to transform Astronomy 101 align with the goals the NRC Committee on Undergraduate Science Education, which I chair; (2) how information technology might be used to advance these goals; and (3) some experiences from our efforts to transform astronomy 101 at the University of Colorado. My work has been supported by grants from the NSF and the Pew Grant Program in Course Redesign.

McCray, R.

2001-12-01

390

Floral Transformation of Wheat  

NASA Astrophysics Data System (ADS)

A method is described for the floral transformation of wheat using a protocol similar to the floral dip of Arabidopsis. This method does not employ tissue culture of dissected embryos, but instead pre-anthesis spikes with clipped florets at the early, mid to late uninucleate microspore stage are dipped in Agrobacterium infiltration media harboring a vector carrying anthocyanin reporters and the NPTII selectable marker. T1 seeds are examined for color changes induced in the embryo by the anthocyanin reporters. Putatively transformed seeds are germinated and the seedlings are screened for the presence of the NPTII gene based on resistance to paromomycin spray and assayed with NPTII ELISAs. Genomic DNA of putative transformants is digested and analyzed on Southern blots for copy number to determine whether the T-DNA has integrated into the nucleus and to show the number of insertions. The non-optimized transformation efficiencies range from 0.3 to 0.6% (number of transformants/number of florets dipped) but the efficiencies are higher in terms of the number of transformants produced/number of seeds set ranging from 0.9 to 10%. Research is underway to maximize seed set and optimize the protocol by testing different Agrobacterium strains, visual reporters, vectors, and surfactants.

Agarwal, Sujata; Loar, Star; Steber, Camille; Zale, Janice

391

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...

392

BIOCONVERSION OF ALPHA-LINOLENIC ACID BY CLAVIBACTER SP. ALA2  

Technology Transfer Automated Retrieval System (TEKTRAN)

Microbial enzyme systems transform unsaturated fatty acids to functional substances. Previously, we reported that Clavibacter sp. ALA2 converted linoleic acid to unique cyclic fatty acids such as diepoxy bicyclic fatty acids (DEOA) and tetrahydrofuranyl fatty acids (THFA) as well as trihydroxy fatty...

393

Genetic transformation of a hepatoprotective plant, Phyllanthus amarus  

Microsoft Academic Search

Phyllanthus amarus Schum & Thonn. is a source of various pharmacologically active compounds such as phyllanthin, hypophyllanthin, gallic acid,\\u000a catechin, and nirurin, a flavone glycoside. A genetic transformation method using Agrobacterium tumefaciens was developed for this plant species for the first time. Shoot tips of full grown plants were used as explants for Agrobacterium-mediated transformation. Transgenic plants were obtained by

Anindita Banerjee; Sharmila Chattopadhyay

2009-01-01

394

Anthranilic acid derivatives and other components from Ononis pusilla.  

PubMed

Three new anthranilic acid derivatives: N-(R)-3'-hydroxydocosanoylanthranilic acid (1), N-(R)-3'-hydroxytricosanoylanthranilic acid (2) and N-(R)-3'-hydroxytetracosanoylanthranilic acid (3), in addition to one knownanthranilic acid and six known flavonoids, were isolated from the ethyl acetate extract of Ononis pusilla L. The structures of the isolated compounds were assigned by spectroscopic methods, including 1D and 2D homo and heteronuclear NMR experiments, ESI-MS, chemical transformation and comparison with literature data. PMID:25233597

Khouni, Lyes; Long, Christophe; Haba, Hamada; Molinier, Nicolas; Benkhaled, Mohammed

2014-08-01

395

Secoiridoids and antifungal aromatic acids from Gentiana algida  

Microsoft Academic Search

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,

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

1996-01-01

396

Acid deposition. Environmental, economic, and policy issues  

SciTech Connect

This book presents information on the following topics: Atmospheric acidification chemistry; SO/sub 2/ oxidation in summertime cloud water at Whiteface Moutain; methods for diagnosing the sources of acid deposition; the use of long range transport models in determining emission control strategies for acid deposition; the sedimentary record of atmospheric pollution in Jerseyfield Lake, Adirondack Mountains, New York; transformation of nitric, sulfuric and organic acids on the Bickford Reservoir watershed; and acidification impacts on fish populations, forest soils and leaf surfaces. The effect of acidity and metal ions on water movement through red spruce is discussed as well as the economic impacts and policy issues associated with acid rain in different countries.

Adams, D.P.; Page, W.P.

1985-01-01

397

Ascorbic Acid  

MedlinePLUS

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

398

Ethacrynic Acid  

MedlinePLUS

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

399

Folic acid  

MedlinePLUS

Folic acid is a water-soluble B vitamin. Since 1998, it has been added to cold cereals, flour, breads, ... law. Foods that are naturally high in folic acid include leafy vegetables (such as spinach, broccoli, and ...

400

Mefenamic Acid  

MedlinePLUS

Mefenamic acid is used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Mefenamic acid is in a class of medications called NSAIDs. ...

401

Aristolochic Acids  

Cancer.gov

Aristolochic acids are a group of acids found naturally in many types of plants known as Aristolochia (birthworts or pipevines) and some types of plants known as Asarum (wild ginger), which grow worldwide.

402

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 ...

403

Aminocaproic Acid  

MedlinePLUS

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

404

Folic Acid  

MedlinePLUS

... acid. Talk to your doctor about how much folic acid you need if you: Are taking medicines used to treat: Epilepsy Type 2 diabetes Rheumatoid arthritis , lupus , psoriasis , asthma , and inflammatory bowel disease Have kidney disease ...

405

Wavelets associated with Hankel transform and their Weyl transforms  

Microsoft Academic Search

The Hankel transform is an important transform. In this paper, we study the wavelets associated with the Hankel transform,\\u000a then define the Weyl transform of the wavelets. We give criteria of its boundedness and compactness on the L\\u000a p — spaces.

Lizhong Peng; Ruiqin Ma

2004-01-01

406

From transformation traces to transformation rules: Assisting Model Driven Engineering  

E-print Network

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

Paris-Sud XI, Université de

407

Laplace Transforms An integral transform is an operator  

E-print Network

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

Ikenaga, Bruce

408

Optical transformation from chirplet to fractional Fourier transformation kernel  

E-print Network

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.

Hong-yi Fan; Li-yun Hu

2009-02-11

409

Verification of ATL Transformations Using Transformation Models and Model Finders  

E-print Network

Verification of ATL Transformations Using Transformation Models and Model Finders Fabian Büttner1 elements of the software to be built. If models are specified well, transformations can be em- ployed by a transformation from valid input models are valid, too, where validity refers to the metamodel constraints, often

Gogolla, Martin - Fachbereich 3

410

Verification of ATL Transformations Using Transformation Models and Model Finders  

E-print Network

Verification of ATL Transformations Using Transformation Models and Model Finders Fabian Büttner1, transformations can be em- ployed for different purposes, e.g., to produce final code. However, it is impor- tant that models produced by a transformation from valid input models are valid, too, where validity refers

Paris-Sud XI, Université de

411

Valproic Acid  

MedlinePLUS

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

412

Shikimic Acid  

NSDL National Science Digital Library

The molecule for this month comes from the article Isolation of Shikimic Acid from Star Aniseed by Richard Payne and Michael Edmonds. Shikimic acid plays a key role in the biosynthesis of many important natural products including aromatic amino acids, alkaloids, phenolics, and phenylpropanoids. It plays such an important role that one of the key biosynthetic pathways is referred to as the shikimate pathway.

413

Generalization of Conformal Transformations  

E-print Network

Conformal transformations of a Euclidean (complex) plane have some kind of completeness (sufficiency) for the solution of many mathematical and physical-mathematical problems formulated on this plane. There is no such completeness in the case of Euclidean, pseudo-Euclidean and polynumber spaces of dimension greater than two. In the present paper we show that using the concepts of analogical geometries allows us to generalize conformal transformations not only to the case of Euclidean or pseudo-Euclidean spaces, but also to the case of Finsler spaces, analogous to the spaces of affine connectedness. Examples of such transformations in the case of complex and hypercomplex numbers H_4 are presented. In the general case such transformations form a group of transitions, the elements of which can be viewed as transitions between projective Euclidean geometries of a distinguished class fixed by the choice of metric geometry admitting affine coordinates. The correlation between functions realizing generalized conformal transformations and generalized analytical functions can appear to be productive for the solution of fundamental problems in theoretical and mathematical physics.

G. I. Garas'ko

2005-09-19

414

Simple immunoassay for detection of PCBs in transformer oil.  

PubMed

A rapid and inexpensive procedure to detect polychlorinated biphenyls (PCBs) in transformer oil is needed to facilitate identification and removal of PCB contaminated transformers. Here we describe a simple two-step liquid-liquid extraction using acidic dimethyl sulfoxide in conjunction with an immunoassay for detecting PCBs in transformer oil. The process described is faster and simpler than any previous immunoassay while maintaining comparable detection limit and false negative rate. Cross reactivity data, characterizing the immunoassay response to the four Kanechlor technical mixtures of PCBs in oil, are presented. Forty-five used transformer oil samples were analyzed by gas chromatography-high-resolution mass spectrometry and were also evaluated using the immunoassay protocol developed. Results presented show zero false negatives at a 1.4 ppm nominal cutoff for the transformer oils analyzed. PMID:16053103

Glass, Thomas R; Ohmura, Naoya; Taemi, Yukihiro; Joh, Takashi

2005-07-01

415

Nature and transformation of dissolved organic matter in treatment wetlands  

USGS Publications Warehouse

This investigation into the occurrence, character, and transformation of dissolved organic matter (DOM) in treatment wetlands in the western United States shows that (i) the nature of DOM in the source water has a major influence on transformations that occur during treatment, (ii) the climate factors have a secondary effect on transformations, (iii) the wetlands receiving treated wastewater can produce a net increase in DOM, and (iv) the hierarchical analytical approach used in this study can measure the subtle DOM transformations that occur. As wastewater treatment plant effluent passes through treatment wetlands, the DOM undergoes transformation to become more aromatic and oxygenated. Autochthonous sources are contributed to the DOM, the nature of which is governed by the developmental stage of the wetland system as well as vegetation patterns. Concentrations of specific wastewaterderived organic contaminants such as linear alkylbenzene sulfonate, caffeine, and ethylenediaminetetraacetic acid were significantly attenuated by wetland treatment and were not contributed by internal loading.

Barber, L.B.; Leenheer, J.A.; Noyes, T.I.; Stiles, E.A.

2001-01-01

416

Contact transformations for difference schemes  

E-print Network

We define a class of transformations of the dependent and independent variables in an ordinary difference scheme. The transformations leave the solution set of the system invariant and reduces to a group of contact transformations in the continuous limit. We use a simple example to show that the class is not empty and that such "contact transformations for discrete systems" genuinely exist.

Decio Levi; Zora Thomova; Pavel Winternitz

2011-10-15

417

Shape transformation for polyhedral objects  

Microsoft Academic Search

Techniques that transform one two-dimensionaf image into another have gained widespread use m recent yeara. Extending these tech- niques to transform pairs of 3D objects, as opposed to 2D images of the objects, providea several advsntagea, including the ability to sn- imate the objects independently of the transformation. This paper presents an algorithm for computing such transformations. The al- gorithm

James R. Kent; Wayne E. Carlson; Richard E. Parent

1992-01-01

418

Invariants of polarization transformations.  

PubMed

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

Sadjadi, Firooz A

2007-05-20

419

Transformation inverse design.  

PubMed

We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is computationally cheap because transformation optics circumvents the need to solve Maxwell's equations at each step. We apply this technique to the design of multimode waveguide bends (realized experimentally in a previous paper) and mode squeezers, in which all modes are transported equally without scattering. In addition to the optimization, a key point is the identification of the correct boundary conditions to ensure reflectionless coupling to untransformed regions while allowing maximum flexibility in the optimization. Many previous authors in transformation optics used a certain kind of quasiconformal map which overconstrained the problem by requiring that the entire boundary shape be specified a priori while at the same time underconstraining the problem by employing "slipping" boundary conditions that permit unwanted interface reflections. PMID:23787612

Liu, David; Gabrielli, Lucas H; Lipson, Michal; Johnson, Steven G

2013-06-17

420

Transformational plasmon optics.  

PubMed

We propose and demonstrate efficiently molding surface plasmon polaritons (SPPs) based on transformation optics. SPPs are surface modes of electromagnetic waves tightly bound at metal-dielectric interfaces, which allow us to scale optics beyond the diffraction limit. Taking advantage of transformation optics, here we show that the propagation of SPPs can be manipulated in a prescribed manner by careful control of the dielectric material properties adjacent to a metal. Since the metal properties are completely unaltered, this methodology provides a practical way for routing light at very small scales. For instance, our approach enables SPPs to travel at uneven and curved surfaces over a broad wavelength range, where SPPs would normally suffer significant scattering losses. In addition, a plasmonic 180 degrees waveguide bend and a plasmonic Luneburg lens with simple designs are presented. The unique design flexibility of the transformational plasmon optics introduced here may open a new door to nano optics and downscaling of photonic circuits. PMID:20465268

Liu, Yongmin; Zentgraf, Thomas; Bartal, Guy; Zhang, Xiang

2010-06-01

421

Plastid transformation in eggplant.  

PubMed

Eggplant (Solanum melongena L.) is an important vegetable crop of tropical and temperate regions of the world. Here we describe a procedure for eggplant plastid transformation, which involves preparation of explants, biolistic delivery of plastid transformation vector into green stem segments, selection procedure, and identification of the transplastomic plants. Shoot buds appear from cut ends of the stem explants following 5-6 weeks of spectinomycin selection after bombardment with the plastid transformation vector containing aadA gene as selectable marker. Transplastomic lines are obtained after the regenerated shoots are subjected to several rounds of spectinomycin selection over a period of 9 weeks. Homoplasmic transplastomic lines are further confirmed by spectinomycin and streptomycin double selection. The transplastomic technology development in this plant species will open up exciting possibilities for improving crop performance, metabolic engineering, and the use of plants as factories for producing biopharmaceuticals. PMID:24599862

Bansal, Kailash C; Singh, Ajay K

2014-01-01

422

Transformation based endorsement systems  

NASA Technical Reports Server (NTRS)

Evidential reasoning techniques classically represent support for a hypothesis by a numeric value or an evidential interval. The combination of support is performed by an arithmetic rule which often requires restrictions to be placed on the set of possibilities. These assumptions usually require the hypotheses to be exhausitive and mutually exclusive. Endorsement based classification systems represent support for the alternatives symbolically rather than numerically. A framework for constructing endorsement systems is presented in which transformations are defined to generate and update the knowledge base. The interaction of the knowledge base and transformations produces a non-monotonic reasoning system. Two endorsement based reasoning systems are presented to demonstrate the flexibility of the transformational approach for reasoning with ambiguous and inconsistent information.

Sudkamp, Thomas

1988-01-01

423

Comparison of Surface Material, Cytoplasmic Filaments, and Intercellular Junctions from Untransformed and Two Mouse Sarcoma Virus-transformed Cell Lines  

Microsoft Academic Search

SUMMARY Surface material, cytoplasmic filaments, and intercellular junctions of an untransformed normal rat kidney (NRK) cell line were compared to those of NRK cells transformed by a nonproductive mouse sarcoma virus and to NRK cells transformed by productive mouse sarcoma virus. Surface material was visualized by ruthenium red (RR) or by staining glycol methacrylate sections with acidic phosphotungstic acid. Normal

Gerald B. Dermer; John Lue; Harry B. Neustem

424

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

Microsoft Academic Search

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,

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

425

Toothpicks and Transformations  

NSDL National Science Digital Library

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.

PBS

2012-01-01

426

Genetic Transformation of Switchgrass  

NASA Astrophysics Data System (ADS)

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.

Xi, Yajun; Ge, Yaxin; Wang, Zeng-Yu

427

Coordinate transformations in quaternion spaces  

E-print Network

The quaternion spaces can be used to describe the property of electromagnetic field and gravitational field. In the quaternion space, some coordinate transformations can be deduced from the feature of quaternions, including Lorentz transformation and Galilean transformation etc., when the coordinate system is transformed into others. And some coordinate transformations with variable speed of light can be obtained in the electromagnetic field and gravitational field.

Zihua Weng

2009-05-15

428

Electrolytic nature of aqueous sulfuric acid. 2. Acidity.  

PubMed

In part 1 of this study, I reported that the Debye-Hückel limiting law and the smaller-ion shell (SiS) model of strong electrolyte solutions fit nicely with the experimental mean ionic activity coefficient (?(±)) of aqueous sulfuric acid as a function of concentration and of temperature when the acid is assumed to be a strong 1-3 electrolyte. Here, I report that the SiS-derived activity coefficient of H(+), ?(H(+)), of the 1-3 acid is comparable to that of aqueous HCl. This agrees with titration curves showing, as well-known, that sulfuric acid in water is parallel in strength to aqueous HCl. The calculated pH is in good accord with the Hammett acidity function, H(0), of aqueous sulfuric acid at low concentration, and differences between the two functions at high concentration are discussed and explained. This pH-H(0) relation is consistent with the literature showing that the H(0) of sulfuric acid (in the 1-9 M range) is similar to those of HCl and the other strong mineral monoprotic acids. The titration of aqueous sulfuric acid with NaOH does not agree with the known second dissociation constant of 0.010 23; rather, the constant is found to be ~0.32 and the acid behaves upon neutralization as a strong diprotic acid practically dissociating in one step. A plausible reaction pathway is offered to explain how the acid may transform, upon base neutralization, from a dissociated H(4)SO(5) (as 3H(+) and HSO(5)(3-)) to a dissociated H(2)SO(4) even though the equilibrium constant of the reaction H(+) + HSO(5)(3-) ? SO(4)(2-) + H(2)O, at 25 °C, is 10(-37) (part 1). PMID:22924595

Fraenkel, Dan

2012-09-27

429

Altered iron homeostasis involvement in arsenite-mediated cell transformation  

PubMed Central

Chronic exposure to low doses of arsenite causes transformation of human osteogenic sarcoma (HOS) cells. Although oxidative stress is considered important in arsenite-induced cell transformation, the molecular and cellular mechanisms by which arsenite transforms human cells are still unknown. In the present study, we investigated whether altered iron homeostasis, known to affect cellular oxidative stress, can contribute to the arsenite-mediated cell transformation. Using arsenite-induced HOS cell transformation as a model, it was found that total iron levels are significantly higher in transformed HOS cells in comparison to parental control HOS cells. Under normal iron metabolism conditions, iron homeostasis is tightly controlled by inverse regulation of ferritin and transferrin receptor (TfR) through iron regulatory proteins (IRP). Increased iron levels in arsenite transformed cells should theoretically lead to higher ferritin and lower TfR in these cells than in controls. However, the results showed that both ferritin and TfR are decreased, apparently through two different mechanisms. A lower ferritin level in cytoplasm was due to the decreased mRNA in the arsenite-transformed HOS cells, while the decline in TfR was due to a lowered IRP-binding activity. By challenging cells with iron, it was further established that arsenite-transformed HOS cells are less responsive to iron treatment than control HOS cells, which allows accumulation of iron in the transformed cells, as exemplified by significantly lower ferritin induction. On the other hand, caffeic acid phenethyl ester (CAPE), an antioxidant previously shown to suppress As-mediated cell transformation, prevents As-mediated ferritin depletion. In conclusion, our results suggest that altered iron homeostasis contributes to arsenite-induced oxidative stress and, thus, may be involved in arsenite-mediated cell transformation. PMID:16443159

Wu, Jing; Eckard, Jonathan; Chen, Haobin; Costa, Max; Frenkel, Krystyna; Huang, Xi

2010-01-01

430

Mineral oxide transformation of antimicrobial contaminants  

NASA Astrophysics Data System (ADS)

The quality of our water supply is dependent on the organic-mineral interface. Organics contain reactive groups that dissolve minerals, and release surface associated contaminants into aquifers and reservoirs. Conversely, minerals may transform organic pollutants, including antimicrobial drugs that are potentially deleterious to aquatic ecosystems or human health. Under aqueous conditions typical of soils and natural waters, the antibiotic agent sulfamethoxazole (SMX) is transformed in the presence of pyrolusite, presumably on the MnO2 surface. At least 50 percent loss of SMX was observed after 269 h, in both acidic and basic solutions (pH 3-9). Nearly 100 percent loss is recorded at pH 3 and 66 percent loss was recorded at circumneutral pH. Initial mass spectrometry of the reaction products suggests an oxidative pathway where hydroxylation and oxidation occurs at the aniline moiety and isoxazolamine ring of SMX. Concomitant increases in aqueous manganese concentrations suggest reductive transformation of the mineral surface. Ongoing electric force spectroscopy and force microscopy experiments probe potential mineral surface alteration associated with the SMX-MnO2 reaction. Coupling bulk aqueous observations and mass spectrometry with molecular-scale force microscopy should further elucidate sulfonamide reactivity as influenced by mineral surface chemistry and topography. Moreover, the observed transformation suggests manganese oxides likely play an important role in the fate of SMX in the environment.

Guo, B.; Kendall, T. A.

2008-12-01

431

Transforming Data into Knowledge  

ERIC Educational Resources Information Center

School systems can be data rich and information poor if they do not understand and manage their data effectively. The task for school leaders is to put existing data into a format that lends itself to answering questions and improving outcomes for the students. Common barriers to transforming data into knowledge in education settings often include…

Mills, Lane

2006-01-01

432

Breakdown of Transformer Oil  

Microsoft Academic Search

Breakdown of transformer oil is affected not only by electrostatic field configurations, but also by many other factors. The latters make it difficult to predict break- down voltage from electrostatic field, as made for air and S F6 gaps. Alternatively, many experimenters tried to express the breakdown stress of oil as a function of stressed oil volume. But, results are

Y. Kawaguchi; H. Murata; M. Ikeda

1972-01-01

433

Computerized toroidal transformer design  

NASA Technical Reports Server (NTRS)

Computer program designs transformers which have one primary /center tap permissible/ and up to 20 untapped secondaries, and which can handle up to 500 V across any one winding. Computer determines total secondary power, core type, primary turns, secondary turns, and wire sizes for primary and secondary windings.

1970-01-01

434

Breakdown of transformer oil  

Microsoft Academic Search

Some of the factors affecting the dielectric strength of transformer oil are investigated. These factors include the stabilization phenomenon, oil and electrode pretreatment, the effect of oil velocity, the effect of a capacitance parallel to the test cell, and the effects of electrode area and gap spacing. The experimental apparatus and procedure are described, and the results are presented for

M. G. Danikas

1990-01-01

435

Multiband cyclic wavelet transforms  

Microsoft Academic Search

Multiresolution analysis via decomposition into wavelets has been established as an important transform technique in signal processing. A wealth of results is available on this subject, the framework has been extended to treat finite length sequences of size 2n (for positive integers n) over finite fields. The paper extends this idea further to provide a framework for dealing with data

Sandip Sarkar; H. V. Poor

1996-01-01

436

Function Transformation without Reinforcement  

ERIC Educational Resources Information Center

In studies of function transformation, participants initially are taught to match stimuli in the presence of a contextual cue, X; the stimuli to be matched bear some formal relation to each other, for example, a relation of opposition or difference. In a second phase, the participants are taught to match arbitrary stimuli (say, A and B) in the…

Tonneau, Francois; Arreola, Fara; Martinez, Alma Gabriela

2006-01-01

437

Fixture for winding transformers  

NASA Technical Reports Server (NTRS)

Bench-mounted fixture assists operator in winding toroid-shaped transformer cores. Toroid is rigidly held in place as wires are looped around. Arrangement frees both hands for rapid winding and untangling of wires that occurs when core is hand held.

Mclyman, M. T.

1980-01-01

438

Transformer Impedance Reflection Demonstration  

ERIC Educational Resources Information Center

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…

Layton, William

2014-01-01

439

Transformer and Meter Tester  

NASA Technical Reports Server (NTRS)

Numerically-controlled 5-axis machine tool uses transformer and meter to determine and indicate whether tool is in home position, but lacks built-in test mode to check them. Tester makes possible test, and repair of components at machine rather then replace them when operation seems suspect.

Stoms, R. M.

1984-01-01

440

Leading System Transformation  

ERIC Educational Resources Information Center

This article outlines progress made towards education transformation in Wales. It explores the way in which tri-level reform is guiding system level change in Wales and looks at the implementation of the School Effectiveness Framework, which is at the heart of the reform process. It describes the way in which professional learning communities are…

Harris, Alma

2010-01-01

441

Review article Genetic transformation  

E-print Network

Review article Genetic transformation: a short review of methods and their applications, results — This report reviews the state-of-the-art in plant genetic engineering, covering both di- rect and indirect gene transfer methods. The application of these techniques to forest trees has been discussed

Paris-Sud XI, Université de

442

Transformations: Translation (NLVM)  

NSDL National Science Digital Library

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.

2011-01-01

443

Transformations: Reflection (NLVM)  

NSDL National Science Digital Library

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.

2011-01-01

444

Transformations: Rotation (NLVM)  

NSDL National Science Digital Library

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.

2011-01-01

445

Fourier Transform Mass Spectrometry.  

ERIC Educational Resources Information Center

Discusses the nature of Fourier transform mass spectrometry and its unique combination of high mass resolution, high upper mass limit, and multichannel advantage. Examines its operation, capabilities and limitations, applications (ion storage, ion manipulation, ion chemistry), and future applications and developments. (JN)

Gross, Michael L.; Rempel, Don L.

1984-01-01

446

Transformation Problem Solving Abilities.  

ERIC Educational Resources Information Center

The relationship between transformation problem performance and Guilford Structure of Intellect (SI) abilities is explored. During two group sessions 42 females and 35 males, age 18-39, were administered 12 Guilford SI tests exemplifying all five symbolic content (numeric) operations, and three contents in the divergent production area. Logical…

Harmel, Sarah Jane

447

An Introductory Transformational Grammar.  

ERIC Educational Resources Information Center

The present volume is directed toward the reader wanting to begin a study of linguistics but who is "overwhelmed by the amount of material available, much of it too technical for him to understand." The author has attempted to provide both theory and applications and has limited the scope to English transformational grammar. Exercises at the end…

Liles, Bruce L.

448

Beyond Reform: Transformation  

ERIC Educational Resources Information Center

The Coalition of Essential Schools (CES) is not a reform movement. To reform is to make a thing again; reformation implies a stasis that doesn't deliver enough for the educational future. This issue of Horace demonstrates that Essential schools and the districts and networks that support them are at various points in the journey of transformation,…

Davidson, Jill

2007-01-01

449

TO TRANSFORM BIOMEDICAL ENGINEERING  

E-print Network

of people suffering from congestive heart failure. His device fits around the heart and restores properIT'S TIME TO TRANSFORM BIOMEDICAL ENGINEERING EDUCATION #12;Charles H. & Bettye Barclay Professor in biomedical engineering research and education ­ and we're well on our way. Our faculty continues to engineer

450

Transforming Education with Technology  

ERIC Educational Resources Information Center

In this EL interview, Karen Cator, the director of the Office of Educational Technology at the U.S. Department of Education, talks about ways to realize the potential of technology to transform education. She discusses what students need: their own digital devices for classroom use, the ability to use the information they access, the skills to…

Scherer, Marge

2011-01-01

451

Transforming American Education  

ERIC Educational Resources Information Center

In this article the authors accept as a given the National Education Technology Plan's vision of a transformed education system powered by technology such that learners receive personalized and engaging learning experiences, and where assessment, teaching, infrastructure, and productivity are redefined. The article analyzes this vision of a…

Horn, Michael B.; Mackey, Katherine

2011-01-01

452

Transforming Education at Einstein  

E-print Network

of Albert Einstein College of Medicine of Yeshiva University #12;2 EinstEin : WintEr/spring 2012 Meet Our trANsfOrMiNg eDuCAtiON At eiNsteiN Education at Albert Einstein College of Medicine is undergoing the magazine for alumni, faculty, students, friends and supporters of Albert einstein College of Medicine

Yates, Andrew

453

Transforming Young Lives  

ERIC Educational Resources Information Center

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…

Larson, Scott

2014-01-01

454

Research Councils UK Transforming  

E-print Network

Research Councils UK Transforming our energy future #12;Research funded by the Research Councils in 2002 to create a viable renewable energy research community to foster industrial engagement of research, expertise and the business capability to develop and exploit them commercially. Energy and its

Berzins, M.

455

Transforming Welsh healthcare.  

PubMed

A fast-track procurement system for Welsh public healthcare projects involving three main project partners "pools" is speeding up the start and completion of hospital building projects, creating a more collaborative, less adversarial working environment, reducing cost and time uncertainties, and driving forward a tranche of schemes aimed at transforming the Welsh healthcare estate by 2015. Jonathan Baillie reports. PMID:19192596

Baillie, Jonathan

2009-01-01

456

ATLAS Job Transforms  

E-print Network

The need to run complex workflows for a high energy physics experiment such as ATLAS has always been present. However, as computing resources have become even more constrained, compared to the wealth of data generated by the LHC, the need to use resources efficiently and manage complex workflows within a single grid job have increased. In ATLAS, a new Job Transform framework has been developed that we describe in this paper. This framework manages the multiple execution steps needed to `transform' one data type into another (e.g., RAW data to ESD to AOD to final ntuple) and also provides a consistent interface for the ATLAS production system. The new framework uses a data driven workflow definition which is both easy to manage and powerful. After a transform is defined, jobs are expressed simply by specifying the input data and the desired output data. The transform infrastructure then executes only the necessary substeps to produce the final data products. The global execution cost of running the job is mini...

Stewart, G A; The ATLAS collaboration; Maddocks, H J; Harenberg, T; Sandhoff, M; Sarrazin, B

2013-01-01

457

Transformation of xanthohumol by Aspergillus ochraceus.  

PubMed

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

Tronina, Tomasz; Bartma?ska, Agnieszka; Pop?o?ski, Jaros?aw; Huszcza, Ewa

2014-01-01

458

Rainbow Fourier Transform  

NASA Technical Reports Server (NTRS)

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).

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

2012-01-01

459

Basically Acids  

NSDL National Science Digital Library

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.

2014-09-18

460

Algorithms for transform selection in multiple-transform video compression  

E-print Network

Selecting proper transforms for video compression has been based on the rate-distortion criterion. Transforms that appear reasonable are incorporated into a video coding system and their performance is evaluated. This ...

Cai, Xun, S.M. Massachusetts Institute of Technology

2012-01-01

461

125. TRANSFORMER SUBSTATIONS ON NORTH SIDE OF TRANSFORMER ROOM (112), ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

125. TRANSFORMER SUBSTATIONS ON NORTH SIDE OF TRANSFORMER ROOM (112), FACING SOUTH - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

462

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...

463

Stereospecific Transformation of Terpinen4-ol to Dihydropinol  

Microsoft Academic Search

A simple transformation of terpinen-4-ol (1) to dihydropinol (4) is described. S-Terpinen-4-ol was stereospecifically oxidized with vanadyl diacac to cis-terpinen-4-ol-epoxide (2). Reduction with LiAlD4 afforded the unexpected 1R-deutero-2S,4S-dihydroxy menthane (3) which was cyclized in acid to 4.

Weiguo Liu; John P. N. Rosazza

1996-01-01

464

Agrobacterium-mediated genetic transformation of Prunus salicina  

Technology Transfer Automated Retrieval System (TEKTRAN)

We report Agrobacterium tumefaciens-mediated transformation from hypocotyls slices of two Prunus salicina varieties, 'Angeleno' and 'Larry Anne', using a modification of the technique previously described for P. domestica. Regeneration rates on thidiazuron (TDZ) and indole-3-butyric acid (IBA) supp...

465

60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

60. VIEW OF THE CURRENT TRANSFORMER VAULT. THIS CURRENT TRANSFORMER WAS USED TO SENSE HIGH CURRENT BEING GENERATED ON GENERATOR NUMBER 3 AND REDUCE IT TO A LOWER, EXACT ANALOG VALUE THAT COULD BE SAFELY HANDLED AND MONITORED WITH THE CONTROL CIRCUITRY. THE CURRENT TRANSFORMER IS LOCATED IN THE CENTER OF THE PHOTOGRAPH. THE CONNECTING BUS ABOVE THE TRANSFORMER WAS REMOVED FOR SALVAGE. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

466

134. VIEW OF TRANSFORMER CABINETS ON NORTH SIDE OF TRANSFORMER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

134. VIEW OF TRANSFORMER CABINETS ON NORTH SIDE OF TRANSFORMER ROOM (212), LSB (BLDG. 751), FACING SOUTH. POWER PANEL B AT EAST SIDE OF TRANSFORMER ROOM (212), FACING WEST, AT RIGHT IN PHOTOGRAPH. - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

467

Detection of inrush current in distribution transformer using wavelet transform  

Microsoft Academic Search

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

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

2005-01-01

468

A DC Transformer  

NASA Technical Reports Server (NTRS)

A component level dc transformer is described in which no alternating currents or voltages are present. It operates by combining features of a homopolar motor and a homopolar generator, both de devices, such that the output voltage of a de power supply can be stepped up (or down) with a corresponding step down (or up) in current. The basic theory for this device is developed, performance predictions are made, and the results from a small prototype are presented. Based on demonstrated technology in the literature, this de transformer should be scalable to low megawatt levels, but it is more suited to high current than high voltage applications. Significant development would be required before it could achieve the kilovolt levels needed for de power transmission.

Youngquist, Robert C.; Ihlefeld, Curtis M.; Starr, Stanley O.

2013-01-01

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