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Sample records for chloroformate solvolysis revisited

  1. Grunwald-Winstein Analysis - Isopropyl Chloroformate Solvolysis Revisited

    Directory of Open Access Journals (Sweden)

    Dennis N. Kevill

    2009-03-01

    Full Text Available Specific rates of solvolysis at 25 °C for isopropyl chloroformate (1 in 24 solvents of widely varying nucleophilicity and ionizing power, plus literature values for studies in water and formic acid, are reported. Previously published solvolytic rate constants at 40.0 °C are supplemented with two additional values in the highly ionizing fluoroalcohols. These rates are now are analyzed using the one and two-term Grunwald-Winstein Equations. In the more ionizing solvents including ten fluoroalcohols negligible sensitivities towards changes in solvent nucleophilicity (l and very low sensitivities towards changes in solvent ionizing power (m values are obtained, evocative to those previously observed for 1-adamantyl and 2-adamantyl chloroformates 2 and 3. These observations are rationalized in terms of a dominant solvolysis-decomposition with loss of the CO2 molecule. In nine of the more nucleophilic pure alchohols and aqueous solutions an association-dissociation mechanism is believed to be operative. Deficiencies in the acid production indicate 2-33% isopropyl chloride formation, with the higher values in less nucleophilic solvents.

  2. Solvolysis study of cycliciminomitomycins.

    Science.gov (United States)

    Na, Younghwa

    2007-03-01

    The solvolysis rates for the substituted C(7)-cyclohexylamino- or C(8)-cyclohexyliminomitomycins 8-19 were determined in buffered methanolic solutions (0.06 M bis-Tris.HCl, pH: 5.5) at 25 degrees C and then compared with mitomycin C (1) and porfiromycin. Kinetic studies showed that C(8)-cyclohexyliminomitomycins 8-13 underwent solvolysis 150-230 times faster than mitomycin C (1) to give C(1)-methoxymitosene products. The solvolysis rates were slightly faster than that reported for 6. The C(7)-(2'-hydroxy)cyclohexylaminomitomycins 16-19 exhibited comparable solvolysis rates with 1 and porfiromycin. PMID:17329899

  3. Solvolysis of lignin, 4

    International Nuclear Information System (INIS)

    In the previous paper, benzyl ethyl ether lignin (BEEL) and 2, 2-dimethoxypropane lignin (DMPL) were prepared by solvolysis of 14C, 3H-double labelled MWL and their structural changes of the phenylpropane unit during the isolation procedure were studied. In this paper, BEEL, DMPL, ethanolysis lignin, dioxane lignin and Klason lignin were prepared from 14C, 3H-double labelled wood meal, in which each carbon of the phenylpropane unit and the hydrogen at the position 2 of the aromatic ring in lignin were labelled with 14C and 3H respectively. The structural changes during the isolation procedure were investigated on each lignin preparation from the changes of 14C/3H ratio. It can be considered that the changes of the ratio indicate the changes of the number of the carbon atoms on each labelled position per aromatic nucleus. The structural changes of BEEL and DMPL were shown to be much less that those of the lignin dissolved in the control experiment in which wood meal was treated in anhydrous dioxane containing 0.5 M HCl. The structural changes of ethanolysis lignin were also as little as those of BEEL or DMPL. Appreciable cleavage of methoxyl groups was observed in dioxane lignin prepared by treating wood meal in dioxane-water containing a small amount of hydrochloric acid at 1000C for 8 hours. In Klason lignin, near the half of 3H on the aromatic ring and a certain amount of γ-carbons and methoxyl groups were lost as an acid soluble fraction. (auth.)

  4. Kinetic Studies that Evaluate the Solvolytic Mechanisms of Allyl and Vinyl Chloroformate Esters

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    Malcolm J. D'Souza

    2013-04-01

    Full Text Available At 25.0 °C the specific rates of solvolysis for allyl and vinyl chloroformates have been determined in a wide mix of pure and aqueous organic mixtures. In all the solvents studied, vinyl chloroformate was found to react significantly faster than allyl chloroformate. Multiple correlation analyses of these rates are completed using the extended (two-term Grunwald-Winstein equation with incorporation of literature values for solvent nucleophilicity (NT and solvent ionizing power (YCl. Both substrates were found to solvolyze by similar dual bimolecular carbonyl-addition and unimolecular ionization channels, each heavily dependent upon the solvents nucleophilicity and ionizing ability.

  5. Kinetic evaluation of the solvolysis of isobutyl chloro- and chlorothioformate esters

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    Song Hee Choi

    2011-04-01

    Full Text Available The specific rates of solvolysis of isobutyl chloroformate (1 are reported at 40.0 °C and those for isobutyl chlorothioformate (2 are reported at 25.0 °C, in a variety of pure and binary aqueous organic mixtures with wide ranging nucleophilicity and ionizing power. For 1, we also report the first-order rate constants determined at different temperatures in pure ethanol (EtOH, methanol (MeOH, 80% EtOH, and in both 97% and 70% 2,2,2-trifluoroethanol (TFE. The enthalpy (ΔH≠ and entropy (ΔS≠ of activation values obtained from Arrhenius plots for 1 in these five solvents are reported. The specific rates of solvolysis were analyzed using the extended Grunwald–Winstein equation. Results obtained from correlation analysis using this linear free energy relationship (LFER reinforce our previous suggestion that side-by-side addition–elimination and ionization mechanisms operate, and the relative importance is dependent on the type of chloro- or chlorothioformate substrate and the solvent.

  6. Neighboring group participation in solvolysis, 13

    International Nuclear Information System (INIS)

    Carbon-14 kinetic isotope effects (k12/k14) were determined for the solvolysis of phenethyl (1a) and 2-(p-methoxyphenyl)ethyl (1b) p-nitrobenzenesulfonates in acetic, formic, and trifluoroacetic acids. Phenyl-1 carbon effects were all in the range of 1.02 - 1.04 except for the acetolysis of 1a (k12/k14 = 1.005), which has been proved to proceed mainly via the aryl unassisted (k sub(s)) pathway. In all other reactions, which proceed mainly via the aryl assisted (k sub(Δ)) pathway, the phenyl-1 carbon apparently changes its bonding in the transition states. A large α-carbon effect (1.131) and a small β-carbon effect (1.013) as well as a mediumphenyl-1 effect (1.022) were observed for the formolysis of 1b, whose mechanism is thought to be exclusive k sub(Δ) without troublesome ion-pair return. These observations, together with α- and β-deuterium effects reported already, enabled us to describe the qualitative nature of the bridged transition-state structure of the k sub(Δ) pathway, i.e., advanced C sub(α)-O bond rupture, slight C sub(α)-C sub(Ph-1) bond formation, C sub(α)-C sub(β) double bond formation, slight C sub(β)-C sub(Ph-1) bond rupture, and breakdown of aromaticity at the phenyl-1 position. These characteristics are very similar to those of the phenonium ion. (author)

  7. Kinetic Studies of the Solvolysis of Two Organic Halides

    Science.gov (United States)

    Duncan, J. A.; Pasto, D. J.

    1975-01-01

    Describes an undergraduate organic chemistry laboratory experiment which utilizes the solvolysis of organic halides to demonstrate first and second order reaction kinetics. The experiment also investigates the effect of a change of solvent polarity on reaction rate, common-ion and noncommon-ion salt effects, and the activation parameters of a…

  8. Correlation of the Rates of Solvolysis of i-Butyl Fluoroformate and a Consideration of Leaving-Group Effects

    Directory of Open Access Journals (Sweden)

    Dennis N. Kevill

    2011-11-01

    Full Text Available The specific rates of solvolysis of isobutyl fluoroformate (1 have been measured at 40.0 °C in 22 pure and binary solvents. These results correlated well with the extended Grunwald-Winstein (G-W equation, which incorporated the NT solvent nucleophilicity scale and the YCl solvent ionizing power scale. The sensitivities (l and m-values to changes in solvent nucleophilicity and solvent ionizing power, and the kF/kCl values are very similar to those observed previously for solvolyses of n-octyl fluoroformate, consistent with the additional step of an addition-elimination pathway being rate-determining. The solvent deuterium isotope effect value (kMeOH/kMeOD for methanolysis of 1 was determined, and for solvolyses in ethanol, methanol, 80% ethanol, and 70% TFE, the values of the enthalpy and the entropy of activation for the solvolysis of 1 were also determined. The results are compared with those reported earlier for isobutyl chloroformate (2 and other alkyl haloformate esters and mechanistic conclusions are drawn.

  9. Solvolysis of titanium tetrachloride in non-aqueous media as a method for producing titanium dioxide particles of different morphology

    OpenAIRE

    A. M Nemeryuk; M. M Lylina

    2015-01-01

    The processes of solvolysis of titanium tetrachloride in nonaqueous media were studied. The influence of the conditions of solvolysis on the size and morphology of the particles of titanium dioxide produced have been described.

  10. Chloroform in the endodontic operatory

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, M.N.; Vire, D.E. (U.S. Army Dental Corps, Fort Sill, OK (United States))

    1992-06-01

    This article reviews the role chloroform has played in dentistry and describes an occupational health clinical investigation into the possible hazards of chloroform use in the operatory. Due to a Food and Drug Administration ban on drugs and cosmetics containing chloroform, there has been some confusion as to whether the use of chloroform in the practice of dentistry is considered unsafe or has been prohibited. Utilizing common endodontic treatment methods employing chloroform, this study reports no negative health effects to the dentist or assistant and air vapor levels well below Occupational Health and Safety Administration mandated maximum levels. The report concludes that, with careful and controlled use, chloroform can be a useful adjunct in the practice of dentistry. The Food and Drug Administration has no jurisdiction over a dentist's use of chloroform in clinical practice and has not proven that chloroform is a human carcinogen.

  11. Koetjapic acid chloroform hemisolvate

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    Z. D. Nassar

    2010-06-01

    Full Text Available The asymmetric unit of the title compound, C30H46O4·0.5CHCl3, consists of one koetjapic acid [systematic name: (3R,4aR,4bS,7S,8S,10bS,12aS-7-(2-carboxyethyl-3,4b,7,10b,12a-pentamethyl-8-(prop-1-en-2-yl-1,2,3,4,4a,4b,5,6,7,8,9,10,10b,11,12,12a-hexadecahydrochrysene-3-carboxylic acid] molecule and one half-molecule of chloroform solvent, which is disordered about a twofold rotation axis. The symmetry-independent component is further disordered over two sites, with occupancies of 0.30 and 0.20. The koetjapic acid contains a fused four-ring system, A/B/C/D. The A/B, B/C and C/D junctions adopt E/trans/cis configurations, respectively. The conformation of ring A is intermediate between envelope and half-chair and ring B adopts an envelope conformation whereas rings C and D adopt chair conformations. A weak intramolecular C—H...O hydrogen bond is observed. The koetjapic acid molecules are linked into dimers by two pairs of intermolecular O—H...O hydrogen bonds. The dimers are stacked along the c axis.

  12. Influence of Sulfur for Oxygen Substitution in the Solvolytic Reactions of Chloroformate Esters and Related Compounds

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    Malcolm J. D'Souza

    2014-10-01

    Full Text Available The replacement of oxygen within a chloroformate ester (ROCOCl by sulfur can lead to a chlorothioformate (RSCOCl, a chlorothionoformate (ROCSCl, or a chlorodithioformate (RSCSCl. Phenyl chloroformate (PhOCOCl reacts over the full range of solvents usually included in Grunwald-Winstein equation studies of solvolysis by an addition-elimination (A-E pathway. At the other extreme, phenyl chlorodithioformate (PhSCSCl reacts across the range by an ionization pathway. The phenyl chlorothioformate (PhSCOCl and phenyl chlorothionoformate (PhOCSCl react at remarkably similar rates in a given solvent and there is a dichotomy of behavior with the A-E pathway favored in solvents such as ethanol-water and the ionization mechanism favored in aqueous solvents rich in fluoroalcohol. Alkyl esters behave similarly but with increased tendency to ionization as the alkyl group goes from 1° to 2° to 3°. N,N-Disubstituted carbamoyl halides favor the ionization pathway as do also the considerably faster reacting thiocarbamoyl chlorides. The tendency towards ionization increases as, within the three contributing structures of the resonance hybrid for the formed cation, the atoms carrying positive charge (other than the central carbon change from oxygen to sulfur to nitrogen, consistent with the relative stabilities of species with positive charge on these atoms.

  13. Scrambling of oxygen-18 during the "borderline" solvolysis of 1-(3-nitrophenyl)ethyl tosylate.

    Science.gov (United States)

    Tsuji, Yutaka; Toteva, Maria M; Amyes, Tina L; Richard, John P

    2004-09-30

    [reaction: see text] There is substantial isomerization (kiso=0.32 x 10(-3) s(-1)) of 3-NO2C6H4(13)CH(Me)OS(18O)2Tos during solvolysis (ksolv=1.04 x 10(-3) s(-1)) in 50/50 trifluoroethanol/water, even though the estimated lifetime of the putative 1-(3-nitrophenyl)ethyl carbocation intermediate of solvolysis (ca. 10(-13) s(-1)) is too short to allow rearrangement that exchanges the positions of 16O and 18O at the sulfonate leaving group. This suggests that isomerization proceeds by a mechanism that avoids formation of the carbocation-anion pair intermediate. PMID:15387566

  14. Solvolysis of the Tumor-Inhibiting Ru(III)-Complex trans-Tetrachlorobis(Indazole)Ruthenate(III).

    Science.gov (United States)

    Pieper, T; Peti, W; Keppler, B K

    2000-01-01

    The ruthenium(III) complex Hlnd trans-[RuCl(4),(ind)(2)], with two trans-standing indazole (ind) ligands bound to ruthenium via nitrogen, shows remarkable activity in different tumor models in vitro and in vivo. The solvolysis of the complex trans-[RuCl(4),(ind)(2)](-) has been investigated by means of spectroscopic techniques (UV/vis, NMR)in different solvents. We investigated the indazolium as well as the sodium salt, the latter showing improved solubility in water. In aqueous acetonitrile and ethanol the solvolysis results in one main solvento complex. The hydrolysis of the complex is more complicated and depends on the pH of the solution as well as on the buffer system. PMID:18475949

  15. Solvolysis of the Tumor-Inhibiting Ru(III)-Complex trans-Tetrachlorobis(Indazole)Ruthenate(III)

    OpenAIRE

    Pieper, Thomas; Peti, Wolfgang; BERNHARD K. KEPPLER

    2000-01-01

    The ruthenium(III) complex Hlnd trans-[RuCl4,(ind)2], with two trans-standing indazole (ind) ligands bound to ruthenium via nitrogen, shows remarkable activity in different tumor models in vitro and in vivo. The solvolysis of the complex trans-[RuCl4,(ind)2]- has been investigated by means of spectroscopic techniques (UV/vis, NMR)in different solvents. We investigated the indazolium as well as the sodium salt, the latter showing improved solubility in water. In aqueous acetonitrile and ethano...

  16. Rate-Product Correlations for the Solvolysis of 5-Nitro-2-Furoyl Chloride

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hojune; Yang, Kiyull; Koo, In Sun [Gyeongsang National Univ., Jinju (Korea, Republic of); Koh, Han Joong [Jeonju National Univ. of Education, Jeonju (Korea, Republic of); Ali, Dildar [Univ. of Balochistan, Quetta (Pakistan)

    2012-10-15

    The solvolysis rate constants of 5-nitro-2-furoyl chloride (5-NO{sub 2}(C{sub 4}H{sub 2}O)-2-COCl, 1) in 27 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N{sub T} solvent nucleophilicity scale and Y{sub Cl} solvent ionizing scale, with sensitivity values of 1.20 ± 0.05 and 0.37 ± 0.02 for l and m, respectively. The activation enthalpies (ΔH{sup ≠}) were 5.63 to 13.0 kcal·mol{sup -1} and the activation entropies (ΔS{sup ≠}) were -25.9 to -43.4 cal·mol{sup -1}·K{sup -1}, which is consistent with the proposed bimolecular reaction mechanism. The solvent kinetic isotope effect (SKIE, k{sub MeOH}/k{sub MeOD}) of 2.65 was also in accord with the S{sub N}2 mechanism and was possibly assisted using a general-base catalysis. The product selectivity (S) for solvolysis of 1 in alcohol/water mixtures was 1.2 to 11, which is also consistent with the proposed bimolecular reaction mechanism.

  17. Bacterial Cellular Materials as Precursors of Chloroform

    Science.gov (United States)

    Wang, J.; Ng, T.; Zhang, Q.; Chow, A. T.; Wong, P.

    2011-12-01

    The environmental sources of chloroform and other halocarbons have been intensively investigated because their effects of stratospheric ozone destruction and environmental toxicity. It has been demonstrated that microorganisms could facilitate the biotic generation of chloroform from natural organic matters in soil, but whether the cellular materials itself also serves as an important precursor due to photo-disinfection is poorly known. Herein, seven common pure bacterial cultures (Acinetobacter junii, Aeromonas hydrophila, Bacillus cereus, Bacillus substilis, Escherichia coli, Shigella sonnei, Staphylococcus sciuri) were chlorinated to evaluate the yields of chloroform, dibromochloromethane, dichlorobromomethane, and bromoform. The effects of bromide on these chemical productions and speciations were also investigated. Results showed that, on average, 5.64-36.42 μg-chloroform /mg-C were generated during the bacterial chlorination, in similar order of magnitude to that generated by humic acid (previously reported as 78 μg-chloroform/mg-C). However, unlike humic acid in water chlorination, chloroform concentration did not simply increase with the total organic carbon in water mixture. In the presence of bromide, the yield of brominated species responded linearly to the bromide concentration. This study provides useful information to understand the contributions of chloroform from photodisinfection processes in coastal environments.

  18. Kinetic Evidence for the Solvent Intervention in the Solvolysis of Tertiary Benzylic Benzoates

    Institute of Scientific and Technical Information of China (English)

    LIU,Kwang-Ting; CHANG,Lih-Wei; CHIN,Chien-Pu

    2006-01-01

    Rates of solvolyses of 2-(4-methylphenyl)-2-propyl benzoate (2b), 2-(4-methylthiophenyl)-2-propyl benzoate (3b) and 2,2-dimethyl-1-(4-methoxyphenyl)-1-phenyl-1-propyl benzoate (4b) were measured, respectively, in ten or more different solvent systems. Additional YBnOPNB and YxBnOPNB values in binary trifluoroethanol-water systems were determined. Grunwald-Winstein type correlation analysis showed that YBnOPNB values were applicable to benzylic benzoates. The rate ratio, kOPNB/kOBz, was found to be solvent-dependent in the range of 29 for 4 in ethanol to 4 for 2 in trifluoroethanol-water. Non-limiting mechanism, including both nucleophilic and electrophilic solvent assistance, in the solvolysis of 2b was discussed.

  19. Nuclear magnetic resonance analysis of the solution and solvolysis of sulfur mustard in deuterium oxide.

    Science.gov (United States)

    Logan, Thomas P; Sartori, David A

    2003-01-01

    Our laboratory performs in vitro experiments in which cell cultures are exposed to sulfur mustard (HD) to investigate the toxicity of this agent of chemical warfare. To perform these experiments, it is important to know the rate of hydrolysis of HD in order to calculate the concentrations of HD and its hydrolysis products during the experiment. Researchers have previously investigated the kinetics and mechanism of the hydrolysis of HD using a variety of methods. In the present study, we used nuclear magnetic resonance (NMR) spectroscopy and gas chromatography/mass spectrometry (GC/MS) to investigate HD's dissolution and solvolysis in deuterium oxide (D 2 O) at 2 mM. We followed activity in proton spectrums and determined the half-life (t 1/2) of HD to be 7.0 +/- 0.5 min in four experiments performed at 22 degrees C. In addition, we determined the t 1/2 of HD in D 2 O containing 0.17 M sodium chloride to be 24 +/- 1 min in three experiments performed at 22 degrees C. As further proof of the existence of HD dissolved into D 2 O, deutero-hexane was used to extract the D 2 O HD solution. The resulting deutero-hexane solution was studied by 1 H NMR and GC/MS. The results obtained match those received from a standard deutero-hexane HD solution. These results demonstrate that HD can be identified in D 2 O with proton NMR and that proton NMR data can be used to monitor the subsequent solvolysis of HD. PMID:20021164

  20. Subchronic chloroform priming protects mice from a subsequently administered lethal dose of chloroform

    International Nuclear Information System (INIS)

    Protection offered by pre-exposure priming with a small dose of a toxicant against the toxic and lethal effects of a subsequently administered high dose of the same toxicant is autoprotection. Although autoprotection has been extensively studied with diverse toxicants in acute exposure regimen, not much is known about autoprotection after priming with repeated exposure. The objective of this study was to investigate this concept following repeated exposure to a common water contaminant, chloroform. Swiss Webster (SW) mice, exposed continuously to either vehicle (5% Emulphor, unprimed) or chloroform (150 mg/kg/day po, primed) for 30 days, were challenged with a normally lethal dose of chloroform (750 mg chloroform/kg po) 24 h after the last exposure. As expected, 90% of the unprimed mice died between 48 and 96 h after administration of the lethal dose in contrast to 100% survival of mice primed with chloroform. Time course studies indicated lower hepato- and nephrotoxicity in primed mice as compared to unprimed mice. Hepatic CYP2E1, glutathione levels (GSH), and covalent binding of 14C-chloroform-derived radiolabel did not differ between livers of unprimed and primed mice after lethal dose exposure, indicating that protection in liver is neither due to decreased bioactivation nor increased detoxification. Kidney GSH and glutathione reductase activity were upregulated, with a concomitant reduction in oxidized glutathione in the primed mice following lethal dose challenge, leading to decreased renal covalent binding of 14C-chloroform-derived radiolabel, in the absence of any change in CYP2E1 levels. Buthionine sulfoximine (BSO) intervention led to 70% mortality in primed mice challenged with lethal dose. These data suggest that higher detoxification may play a role in the lower initiation of kidney injury observed in primed mice. Exposure of primed mice to a lethal dose of chloroform led to 40% lower chloroform levels (AUC15-360min) in the systemic circulation

  1. Mechanism on microwave-assisted acidic solvolysis of black-liquor lignin.

    Science.gov (United States)

    Dong, Chengjian; Feng, Chunguang; Liu, Qian; Shen, Dekui; Xiao, Rui

    2014-06-01

    Microwave-assisted degradation of black-liquor lignin with formic acid was studied, concerning the product yield and distribution of phenolic compounds against reaction temperature (110-180°C) and reaction time (5-90 min). The liquid product consisting of bio-oil 1 and bio-oil 2, achieved the maxima yield of 64.08% at 160°C and 30 min (bio-oil 1: 9.69% and bio-oil 2: 54.39%). The chemical information of bio-oil 1 and bio-oil 2 were respectively identified by means of Gas Chromatography-Mass Spectrometer (GC-MS) and Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), while the solid residue was analyzed by Gel Permeation Chromatography (GPC) and Fourier Transform Infrared Spectroscopy (FTIR). A possible mechanism was proposed for the microwave-assisted acidic solvolysis of lignin, specifying the kinetic relationship among the primary cracking of lignin, repolymerization of the oligomers and formation of solid residue. PMID:24747392

  2. Reactor for Photocatalytic Degradation of Chloroform

    DEFF Research Database (Denmark)

    Simonsen, Morten Enggrob; Søgaard, Erik Gydesen

    In the present study a new type of continuous photoreactor is developed in which the TiO2 catalyst is immobilized on the surface of quartz tubes surrounding the UV lamps and on the internal surface of the reactor walls. The study showed that an initial concentration chloroform of 7 mg/l was degra......In the present study a new type of continuous photoreactor is developed in which the TiO2 catalyst is immobilized on the surface of quartz tubes surrounding the UV lamps and on the internal surface of the reactor walls. The study showed that an initial concentration chloroform of 7 mg....../l was degraded in a period of 500 hour. The kinetics of the degradation of chloroform in the flow reactor was found to obey Langmuir-Hinshelwood kinetics. The investigation also showed that the reactor design has a significant influence on the rate of degradation, as it was observed that the position...... of the coated lamp in the reactor yield different degradation rates....

  3. Formation, fate and leaching of chloroform in coniferous forest soils

    International Nuclear Information System (INIS)

    Research highlights: → Chloroform may be formed in coniferous forest soil. → The formed chloroform may enter the groundwater in μg/L concentrations. → Clear seasonal patterns in chloroform formation in soil are observed. → Sorption and degradation affects the fate of chloroform in forest soil. - Abstract: Chloroform is a common groundwater pollutant but also a natural compound in forest ecosystems. Leaching of natural chloroform from forest soil to groundwater was followed by regular analysis of soil air and groundwater from multilevel wells at four different sites in Denmark for a period of up to 4 a. Significant seasonal variation in chloroform was observed in soil air 0.5 m below surface ranging at one site from 120 ppb by volume in summer to 20 ppb during winter. With depth, the seasonal variation diminished gradually, ranging from 30 ppb in summer to 20 ppb during winter, near the groundwater table. Chloroform in the shallowest groundwater ranged from 0.5-1.5 μg L-1 at one site to 2-5 μg L-1 at another site showing no clear correlation with season. Comparing changes in chloroform in soil air versus depth with on-site recorded meteorological data indicated that a clear relationship appears between rain events and leaching of chloroform. Chloroform in top soil air co-varied with CO2 given a delay of 3-4 weeks providing evidence for its biological origin. This was confirmed during laboratory incubation experiments which further located the fermentation layer as the most chloroform producing soil horizon. Sorption of chloroform to soils, examined using 14C-CHCl3, correlated with organic matter content, being high in the upper organic rich soils and low in the deeper more minerogenic soils. The marked decrease in chloroform in soil with depth may in part be due to microbial degradation which was shown to occur at all depths by laboratory tests using 14C-CHCl3.

  4. Investigation of Solvolysis Kinetics of New Synthesized Fluocinolone Acetonide C-21 Esters—An In Vitro Model for Prodrug Activation

    Directory of Open Access Journals (Sweden)

    Katarina D. Karljikovic-Rajic

    2011-03-01

    Full Text Available In this study the solvolysis of newly synthesized fluocinolone acetonide C-21 esters was analysed in comparison with fluocinonide during a 24-hour period of time. The solvolysis was performed in an ethanol-water (90:10 v/v mixture using the excess of NaHCO3. The solvolytic mixtures of each investigated ester have been assayed by a RP-HPLC method using isocratic elution with methanol-water (75:25 v/v; flow rate 1 mL/min; detection at 238 nm; temperature 25 °C. Solvolytic rate constants were calculated from the obtained data. Geometry optimizations and charges calculations were carried out by Gaussian W03 software. A good correlation (R = 0.9924 was obtained between solvolytic rate constants and the polarity of the C-O2 bond of those esters. The established relation between solvolytic rate constant (K and lipophilicity (cLogP with experimental anti-inflammatory activity could be indicative for topical corticosteroid prodrug activation.

  5. ANALYSIS OF THE KINETICS OF SOLVOLYSIS OF P-NITROPHENYLSULFONYLMETHYL PERCHLORATE IN BINARY ALCOHOLIC MIXTURES IN TERMS OF THE THERMODYNAMIC PROPERTIES OF THE SOLVENT MIXTURES

    NARCIS (Netherlands)

    WIJNEN, JW; ENGBERTS, JBFN; BLANDAMER, MJ

    1993-01-01

    Rate constants are reported for the solvolysis of p-nitrophenylsulfonylmethyl perchlorate in binary ethanolic and methanolic mixtures at 298.2 K. Co-solvents include hydrocarbons, chlorinated hydrocarbons and 1,4-dioxane. The kinetic data are examined in terms of the effect of decreasing mole fracti

  6. Formation, fate and leaching of chloroform in coniferous forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Albers, Christian N., E-mail: calbers@ruc.dk [Dept. Geochemistry, Geological Survey of Denmark and Greenland, O. Voldgade 10, DK-1350, Copenhagen (Denmark); Laier, Troels; Jacobsen, Ole S. [Dept. Geochemistry, Geological Survey of Denmark and Greenland, O. Voldgade 10, DK-1350, Copenhagen (Denmark)

    2010-10-15

    Research highlights: {yields} Chloroform may be formed in coniferous forest soil. {yields} The formed chloroform may enter the groundwater in {mu}g/L concentrations. {yields} Clear seasonal patterns in chloroform formation in soil are observed. {yields} Sorption and degradation affects the fate of chloroform in forest soil. - Abstract: Chloroform is a common groundwater pollutant but also a natural compound in forest ecosystems. Leaching of natural chloroform from forest soil to groundwater was followed by regular analysis of soil air and groundwater from multilevel wells at four different sites in Denmark for a period of up to 4 a. Significant seasonal variation in chloroform was observed in soil air 0.5 m below surface ranging at one site from 120 ppb by volume in summer to 20 ppb during winter. With depth, the seasonal variation diminished gradually, ranging from 30 ppb in summer to 20 ppb during winter, near the groundwater table. Chloroform in the shallowest groundwater ranged from 0.5-1.5 {mu}g L{sup -1} at one site to 2-5 {mu}g L{sup -1} at another site showing no clear correlation with season. Comparing changes in chloroform in soil air versus depth with on-site recorded meteorological data indicated that a clear relationship appears between rain events and leaching of chloroform. Chloroform in top soil air co-varied with CO{sub 2} given a delay of 3-4 weeks providing evidence for its biological origin. This was confirmed during laboratory incubation experiments which further located the fermentation layer as the most chloroform producing soil horizon. Sorption of chloroform to soils, examined using {sup 14}C-CHCl{sub 3}, correlated with organic matter content, being high in the upper organic rich soils and low in the deeper more minerogenic soils. The marked decrease in chloroform in soil with depth may in part be due to microbial degradation which was shown to occur at all depths by laboratory tests using {sup 14}C-CHCl{sub 3}.

  7. Information draft on the development of air standards for chloroform

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-01-01

    Chloroform is used as a grain fumigant and a solvent for pesticides, adhesives, fats, oils, rubbers, alkaloids and waxes. It is also a chemical intermediate for dyes and pesticides, a component of cough syrups, toothpastes, and liniments. It is used in fire extinguishers, in the manufacture of refrigerants, propellants, plastics, anesthetics and pharmaceuticals. Of the releases into the air in 1996 in Ontario (36.7 tonnes), over 96 per cent was attributed to the pulp and paper industry. Chloroform is well absorbed in exposed animals and humans through ingestion, inhalation, and dermal contact. Once absorbed, the chloroform distributes throughout the entire body. Metabolism of chloroform involves cytochrome P-450 in an oxidative biotransformation to produce trichloromethanol with phosgene as its intermediate product and finally hydrochloric acid and carbon dioxide. Chloroform is a central nervous system depressant and a gastrointestinal irritant. Exposure to chloroform can cause fainting, vomiting, dizziness, nausea, fatique and headache. Its most universally observed toxic effect is liver damage. Chloroform is not known to be carcinogenic in humans, but there is sufficient evidence to suggest that it is an animal carcinogen. The current Ontario air quality standard and criterion for chloroform was established in 1979. The half-hour interim POI standard is 1,500 microgram/cubic meter, and the 24-hour AAQC is 500 microgram/cubic meter. This document reviews the scientific and technical information relevant to setting an ambient air quality standard for chloroform in Ontario. The information is gathered from standards and guidelines developed by the federal government, the US Environmental Protection Agency, the World Health Organization, Scandinavia, the Netherlands, and various American states. 59 refs., 1 tab., appendix.

  8. Recycling of CFRP for high value applications: Effect of sizing removal and environmental analysis of the SuperCritical Fluid Solvolysis

    OpenAIRE

    DAUGUET, Michel; MANTAUX, Olivier; PERRY, Nicolas; ZHAO, Yaoyao Fiona

    2015-01-01

    The recycling of Carbon Fibers Reinforced Plastics (CFRP) wastes is becoming increasingly important in the aerospace industry. For most of the technologies, the recycled CF (rCF) are discontinuous, misaligned and unsized. Compared to thermal treatments, the orientation, the length and the brittleness of the rCF are better preserved with the SuperCritical Water Solvolysis (SCWS). The effect of the sizing removal on the recycled CFRP behavior is studied by conducting static characterizations. R...

  9. Formation of chloroform in soil. A year-round study at a Danish spruce forest site

    DEFF Research Database (Denmark)

    Haselmann, K.F.; Laturnus, F.; Grøn, C.

    2002-01-01

    to ambient air concentrations indicated a natural production of chloroform, while the other chlorinated compounds investigated probably originated from non-point source pollution. The seasonal variation of the chloroform concentration suggested a production by microorganisms, as high chloroform...

  10. Tracing tissues with chloroform-metabolizing capacity in rats

    International Nuclear Information System (INIS)

    Rats were injected i.v. or i.p. with (14C)chloroform and the localization and binding of metabolites in the tissues were studied by whole-body and microautoradiography. Based on the autoradiographic findings various tissues were tested for their capacity to form 14CO2 and to incorporate 14C into tissue-macromolecules from the (14C) chloroform. Autoradiography in vitro was used to localize the sites of (14C)chloroform metabolism under in vitro conditions. The results of the vitro metabolism studies showed that several tissues had a capacity to metabolise the (14C)chloroform. Further, the results showed that there was a correlation between the ability of various tissues to accumulate metabolites in the rats injected with the (14C)chloroform and the ability of the same tissues to metabolize the (14C)chloroform in vitro. The in vitro autoradiography showed an acculumlation of radioactivity at sites corresponding to the ones acculmulating metabolites in vivo. It is concluded that many tissues have a capacity to metabolize chloroform in vivo and in vitro. The structures identified as having a marked chloroform-metabolizing capacity were, besides the liver, the kidney cortex, the mucosa of the bronchial tree, the tracheal mucosa, the olfactory and respiratory nasal mucosa, Bowman's glands in the olfactory lamina propria mucosae, Steno's gland (the lateral nasal gland), the mucosa of the oesophagus, the larynx, the tongue, the gingiva, the cheek, the naso-pharyngeal duct, the pharynx and the soft palate (but not the hard palate). (Author)

  11. Durability of organobentonite-amended liner for decelerating chloroform transport.

    Science.gov (United States)

    He, Shichong; Zhu, Lizhong

    2016-04-01

    Chloroform is added to landfill for suppressing methane generation, which however may transport through landfill liners and lead to contamination of groundwater. To decelerate chloroform transport, the enhanced sorption ability of clay liners following organobentonite addition was tested. In this study, we used batch sorption to evaluate sorption capacity of chloroform to organobentonite, followed by column tests and model simulations for assessing durability of different liners. Results show that adding 10% CTMAB-bentonite (organobentonite synthesized using cetyltrimethylammonium bromide) increased the duration of a bentonite liner by 88.5%. CTMAB-bentonite consistently showed the highest sorption capacity (Qm) among six typical organobentonites under various environmental conditions. The removal rate of chloroform by CTMAB-bentonite was 3.6-23 times higher than that by natural soils. According to the results derived by model simulation, a 70-cm 10% CTMAB-bentonite liner exhibited much better durability than a 100-cm compact clay liner (CCL) and natural bentonite liner evidenced by the delayed and lower peak of eluent concentration. A minimum thickness of 65.8 cm of the 10% CTMAB-bentonite liner could completely sorb the chloroform in a 100-m-high landfill. The 10% CTMAB-bentonite liner exhibiting much better durability has the promise for reducing environmental risk of chloroform in landfill. PMID:26874063

  12. Temperature dependence of the rate and activation parameters for tert-butyl chloride solvolysis: Monte Carlo simulation of confidence intervals

    Science.gov (United States)

    Sung, Dae Dong; Kim, Jong-Youl; Lee, Ikchoon; Chung, Sung Sik; Park, Kwon Ha

    2004-07-01

    The solvolysis rate constants ( kobs) of tert-butyl chloride are measured in 20%(v/v) 2-PrOH-H 2O mixture at 15 temperatures ranging from 0 to 39 °C. Examination of the temperature dependence of the rate constants by the weighted least squares fitting to two to four terms equations has led to the three-term form, ln kobs= a1+ a2T-1+ a3ln T, as the best expression. The activation parameters, ΔH ‡ and ΔS ‡, calculated by using three constants a1, a2 and a3 revealed the steady decrease of ≈1 kJ mol -1 per degree and 3.5 J K -1 mol -1 per degree, respectively, as the temperature rises. The sign change of ΔS ‡ at ≈20.0 °C and the large negative heat capacity of activation, ΔC p‡=-1020 J K -1 mol -1, derived are interpreted to indicate an S N1 mechanism and a net change from water structure breaking to electrostrictive solvation due to the partially ionic transition state. Confidence intervals estimated by the Monte Carlo method are far more precise than those by the conventional method.

  13. Photooxidation of papaverine, papaverinol and papaveraldine in their chloroform solutions.

    Science.gov (United States)

    Piotrowska, Karolina; Hermann, Tadeusz W; Augustyniak, Włodzimierz

    2002-01-01

    Papaverine hydrochloride, papaverinol, and papaveraldine chloroform solutions were exposed to UV light of 254 nm in atmospheric, aerobic and anaerobic (helium) conditions. The same degradation products appear (TLC) in the above papaverine hydrochloride chloroform solutions. However, the rate of papaverine hydrochloride degradation processes is enhanced as a function of oxygen pressure. Papaverinol and papaveraldine photooxidation products are essentially not different from those observed in the above papaverine hydrochloride solutions. However, the amount of an unknown brown degradation product (X) is the greatest in the papaverinol chloroform solution degraded. That brown compound was previously observed in papaverine either hydrochloride or sulfate injection solutions on their storage even when protected from daylight. The preliminary X product structure development was undertaken (TLC, molecular weight, elemental analysis, UV/VIS, IR and 13C MAS NMR spectroscopy).

  14. Chloroform alters interleaflet coupling in lipid bilayers: an entropic mechanism

    Science.gov (United States)

    Reigada, Ramon; Sagués, Francesc

    2015-01-01

    The interaction of the two leaflets of the plasmatic cell membrane is conjectured to play an important role in many cell processes. Experimental and computational studies have investigated the mechanisms that modulate the interaction between the two membrane leaflets. Here, by means of coarse-grained molecular dynamics simulations, we show that the addition of a small and polar compound such as chloroform alters interleaflet coupling by promoting domain registration. This is interpreted in terms of an entropic gain that would favour frequent chloroform commuting between the two leaflets. The implication of this effect is discussed in relation to the general anaesthetic action. PMID:25833246

  15. Novel Carboxylic Acid Solvolysis Route to Synthesis Electrode-active Nanostructured Spinel-Li_4Ti_5O_(12) for Lithium Batteries and Hybrid Capacitors

    Institute of Scientific and Technical Information of China (English)

    Teressa; Nathan; Michael; Cloke; S; R; S; Prabaharan

    2007-01-01

    1 Results Nanostructured spinel-type Li4Ti5O12 (LTO) was prepared using Lewis acid base reaction technique involving a mixture of titanium β-diketonate and lithium nitrate as starting materials in the presence of aqueous citric acid as a solvolysis agent. The above method yielded a simple single step process without involving sol to gel conversion. The phase purity of the synthesized product after calcining at 800 ℃ for 24 h in air showed a spinel structure without any residual impurities. The nanostru...

  16. Biological Hydrogen Production Using Chloroform-treated Methanogenic Granules

    Science.gov (United States)

    Hu, Bo; Chen, Shulin

    In fermentative hydrogen production, the low-hydrogen-producing bacteria retention rate limits the suspended growth reactor productivity because of the long hydraulic retention time (HRT) required to maintain adequate bacteria population. Traditional bacteria immobilization methods such as calcium alginate entrapment have many application limitations in hydrogen fermentation, including limited duration time, bacteria leakage, cost, and so on. The use of chloroform-treated anaerobic granular sludge as immobilized hydrogen-producing bacteria in an immobilized hydrogen culture may be able to overcome the limitations of traditional immobilization methods. This paper reports the findings on the performance of fed-batch cultures and continuous cultures inoculated with chloroform-treated granules. The chloroform-treated granules were able to be reused over four fed-batch cultures, with pH adjustment. The upflow reactor packed with chloroform-treated granules was studied, and the HRT of the upflow reactor was found to be as low as 4 h without any decrease in hydrogen production yield. Initial pH and glucose concentration of the culture medium significantly influenced the performance of the reactor. The optimum initial pH of the culture medium was neutral, and the optimum glucose concentration of the culture medium was below 20 g chemical oxygen demand/L at HRT 4 h. This study also investigated the possibility of integrating immobilized hydrogen fermentation using chloroform-treated granules with immobilized methane production using untreated granular sludge. The results showed that the integrated batch cultures produced 1.01 mol hydrogen and 2 mol methane per mol glucose. Treating the methanogenic granules with chloroform and then using the treated granules as immobilized hydrogen-producing sludge demonstrated advantages over other immobilization methods because the treated granules provide hydrogen-producing bacteria with a protective niche, a long duration of an active

  17. Phase equilibrium data for the ternary system (propane + chloroform + oryzanol)

    Energy Technology Data Exchange (ETDEWEB)

    Correa, Fernanda V.; Comim, Sibele R.R. [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Cesaro, Aline M. de; Rigo, Aline A.; Mazutti, Marcio A. [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil); Hense, Haiko [EQA/UFSC, Chemical and Food Engineering Department, Federal University of Santa Catarina, C.P. 476, CEP 88040-900, Florianopolis, SC (Brazil); Oliveira, J. Vladimir, E-mail: vladimir@uricer.edu.b [Department of Food Engineering, URI - Campus de Erechim, Av. Sete de Setembro, 1621, 99700-000 Erechim, RS (Brazil)

    2011-01-15

    The compound oryzanol available in the rice bran (oriza sativa) is well known for its antioxidant activity. Phase equilibrium data involving oryzanol in compressed fluids, hardly found in the literature, are important to provide the basis for the extraction and fractionation processes. In this sense, the aim of this work is to report phase equilibrium measurements for the system ({gamma}-oryzanol + chloroform) in compressed propane. Phase equilibrium experiments were performed using the static synthetic method (cloud points transition data) in a high-pressure variable-volume view cell in the temperature range of 303 K to 353 K, pressures up to 17 MPa, for oryzanol overall mass fractions of 2 wt%, 5 wt% and 10 wt% in (propane + chloroform) mixtures. A complex phase behaviour comprising vapour-liquid, liquid-liquid, vapour-liquid-liquid, solid-liquid, solid-liquid-liquid, solid-liquid-liquid-vapour transitions were visually observed for the system studied.

  18. THE PRESERVATION OF SOME ORAL LIQUID PREPARATIONS - THE REPLACEMENT OF CHLOROFORM BY OTHER PRESERVATIVES

    NARCIS (Netherlands)

    VANDOORNE, H; LEIJEN, JB

    1994-01-01

    Chloroform should be considered as an obsolete preservative for,pharmaceutical preparations, because of its toxicological implications and its physical instability. The effectiveness oi possible alternatives for chloroform in three-oral liquid pharmaceutical preparations was investigated, using a mi

  19. Graphene oxide and adsorption of chloroform: A density functional study

    Science.gov (United States)

    Kuisma, Elena; Hansson, C. Fredrik; Lindberg, Th. Benjamin; Gillberg, Christoffer A.; Idh, Sebastian; Schröder, Elsebeth

    2016-05-01

    Chlorinated hydrocarbon compounds are of environmental concerns, since they are toxic to humans and other mammals, and are widespread, and exposure is hard to avoid. Understanding and improving methods to reduce the amount of the substances are important. We present an atomic-scale calculational study of the adsorption of chlorine-based substance chloroform (CHCl3) on graphene oxide, as a step in estimating the capacity of graphene oxide for filtering out such substances, e.g., from drinking water. The calculations are based on density functional theory, and the recently developed consistent-exchange functional for the van der Waals density-functional method is employed. We obtain values of the chloroform adsorption energy varying from roughly 0.2 to 0.4 eV per molecule. This is comparable to previously found results for chloroform adsorbed directly on clean graphene, using similar calculations. In a wet environment, like filters for drinking water, the graphene will not stay clean and will likely oxidize, and thus adsorption onto graphene oxide, rather than clean graphene, is a more relevant process to study.

  20. Graphene oxide and adsorption of chloroform: a density functional study

    CERN Document Server

    Kuisma, Elena; Lindberg, Th Benjamin; Gillberg, Christoffer A; Idh, Sebastian; Schroder, Elsebeth

    2016-01-01

    Chlorinated hydrocarbon compounds are of environmental concerns, since they are toxic to humans and other mammals, are widespread, and exposure is hard to avoid. Understanding and improving methods to reduce the amount of the substances is important. We present an atomic-scale calculational study of the adsorption of chlorine-based substance chloroform (CHCl3) on graphene oxide, as a step in estimating the capacity of graphene oxide for filtering out such substances, e.g., from drinking water. The calculations are based on density functional theory (DFT), and the recently developed consistent-exchange functional for the van der Waals density-functional method (vdW-DF-cx) is employed. We obtain values of the chloroform adsorption energy varying from roughly 0.2 to 0.4 eV per molecule. This is comparable to previously found results for chloroform adsorbed directly on clean graphene, using similar calculations. In a wet environment, like filters for drinking water, the graphene will not stay clean and will likel...

  1. 21 CFR 700.18 - Use of chloroform as an ingredient in cosmetic products.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Use of chloroform as an ingredient in cosmetic... SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.18 Use of chloroform as an ingredient in cosmetic products. (a) Chloroform has been used as an ingredient in...

  2. Solvolysis of lignin, 3

    International Nuclear Information System (INIS)

    Double labelled MWL, in which each carbon of the phenylpropane unit and the hydrogen at the position 2 of the aromatic ring were labelled with 14C and 3H respectively, were treated with benzyl ethyl ether of 2,2-dimethoxypropane in anhydrous dioxane containing 0.5 M HCl at 900C for 3 hours. From the changes of 14C/3H ratio of MWL during the reaction, it was suggested that the structural changes of the phenylpropane unit of MWL during the reaction could be considerably reduced by the presence of a solvolytic reagent compared with the reaction in the absence of it. Especially 2,2-dimethoxypropane seemed to depolymerize a larger amount of MWL with less structural changes of the phenylpropane unit. This method using double labelled lignin is expected to be a more reliable means of structural investigations of lignin than conventional tracer experiments using 14C-single labelled lignin, because it can be considered that the experimental results obtained by this method are hardly affected by unequalities among lignin preparations. (auth.)

  3. Carbon nanofibers synthesized by pyrolysis of chloroform and ethanol mixture

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Wang-Hua [Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, 62102, Taiwan (China); Li, Yuan-Yao, E-mail: chmyyl@ccu.edu.tw [Department of Chemical Engineering, National Chung Cheng University, Chia-Yi, 62102, Taiwan (China); Graduate Institute of Opto-Mechatronics, National Chung Cheng University, Chia-Yi, 62102, Taiwan (China); Advanced Institute of Manufacturing with High-Tech Innovations, National Chung Cheng University, Chia-Yi, 62102, Taiwan (China)

    2015-08-01

    Platelet graphite nanofibers (PGNFs) and turbostratic carbon nanofibers (TSCNFs) were synthesized by the pyrolysis of 3 and 10 vol% chloroform in ethanol, respectively, in the presence of Ni catalyst at 700 °C. Auger electron spectrometry analysis reveals that the participation of chloroform in the synthesis led to Ni–Cl bonding on the surface of the catalysts, resulting in a relatively poor crystalline layer and a coarse surface. Furthermore, the Ni–Cl compound affected the melting point and mobility of Ni, changing the morphology and geometrical shape of Ni particles. A low amount of chlorine in the catalyst led to the formation of smaller catalyst particles with a flat surface, resulting in graphene nanosheets stacked perpendicular to the fiber axis, which became PGNFs. In contrast, a high amount of chlorine in the catalyst led to the aggregation of the catalyst and thus the formation of large catalyst particles with a rough surface, resulting in the random stacking of graphene nanosheets, which became TSCNFs. The participation of chlorine was found to be important in the synthesis of the PGNFs and TSCNFs. - Graphical abstract: Display Omitted - Highlights: • The morphology of CNFs changed while different amount of CHCl{sub 3} presented. • The interaction of Ni and Cl changed the geometry and morphology of catalysts. • The structure of CNFs formed attributed to the surface morphology of catalysts. • PGNFs and TSCNFs were perpendicular and random stacking of graphene.

  4. Contribution of natural terrestrial sources to the atmospheric chloroform budget

    Science.gov (United States)

    Rhew, R. C.; Abel, T.; Pan, D.; Whelan, M.

    2008-12-01

    Chloroform (trichloromethane, CHCl3) is the second largest carrier of natural chlorine in the troposphere after methyl chloride, contributing to the reactive chlorine burden in the troposphere and to ozone destruction in the stratosphere. Our understanding of the biogeochemical cycling of atmospheric CHCl3 has undergone major adjustments recently, including the quantification of the total atmospheric burden of this compound, the estimated global source and sink strengths, and the relative contributions of anthropogenic versus natural contributions. Numerous natural terrestrial sources have been identified, including temperate peatlands, Arctic tundra, termite mounds, salt marshes, grasslands, forests and woodlands. However, the wide variability of fluxes within each ecosystem has complicated efforts to quantify the overall terrestrial source. In addition, the environmental and biogeochemical controls remain largely unknown. We shall present a comparison of recent CHCl3 flux measurements that cover a range of biome types and climatic conditions. To address within-biome variability, flux measurements from the Arctic tundra and temperate grasslands will be compared to common environmental parameters (e.g., temperature, soil moisture, solar insolation) and other trace gas fluxes (CH3Cl, CH4, CCl4). The generally poor correlations demonstrate that the variability of CHCl3 emissions may be affected by site-specific parameters that are not currently measured or by drastic changes in hydrologic conditions. Similar patterns are observed in laboratory incubations of tundra peat and grassland soils. We explore the possibility that the humification of plant material, which has been shown to produce organochlorine compounds through the chlorination of organic matter, may contribute to CHCl3 emissions. If this link exists, then CHCl3 production could potentially act as a proxy for organic matter degradation and carbon sequestration, essential biogeochemical and ecosystem

  5. Chloroform formation in Arctic and Subarctic soils - mechanism and emissions to the atmosphere

    Science.gov (United States)

    Albers, Christian N.; Johnsen, Anders R.; Jacobsen, Ole S.

    2015-04-01

    It is well established that halogenated organic compounds are formed naturally in the terrestrial environment. These compounds include volatiles such as trihalomethanes that may escape to the atmosphere. In deed most of the atmospheric chloroform (and other trihalomethane species) is regarded to have a natural origin. This origin may be both marine and terrestrial. Chloroform formation in soil has been reported in a number of studies, mostly conducted in temperate and (sub-) tropical environments. We hereby report that also colder soils emit chloroform naturally. We measured in situ the fluxes of chloroform from soil to atmosphere in 6 Subarctic and 5 Arctic areas covering different dwarf heath, wetland and forest biotopes in Greenland and Northern Sweden. Emissions were largest from the forested areas, but all areas emitted measurable amounts of chloroform. Also the brominated analog bromodichloromethane was formed in Arctic and Subarctic soils but the fluxes to the atmosphere were much lower than the corresponding chloroform emissions. No other volatile poly-halogenated organic compounds were found to be emitted from the study areas. It has previously been proposed that chloroform is formed in temperate forest soils through trichloroacetyl intermediates formed by unspecific enzymatic chlorination of soil organic matter. We found positive relationships between chloroform emissions and the concentration of trichloroacetyl groups in soil within the various biotopes. The hydrolysis of trichloroacetyl compounds is, however, very pH dependent, excluding a simple relationship between trichloroacetyl concentration and chloroform emission in any given soil. However, our results show that at low pH, turnover time of soil trichloroacetyl compounds may be counted in decades while at pH above 6, turnover time may be just a few months. We found no relationship between trichloroacetyl concentration and total organic chlorine concentration in the soils indicating that more than

  6. Adaptive tolerance in mice upon subchronic exposure to chloroform: Increased exhalation and target tissue regeneration

    International Nuclear Information System (INIS)

    The aims of the present study were to characterize the subchronic toxicity of chloroform by measuring tissue injury, repair, and distribution of chloroform and to assess the reasons for the development of tolerance to subchronic chloroform toxicity. Male Swiss Webster (SW) mice were given three dose levels of chloroform (150, 225, and 300 mg/kg/day) by gavage in aqueous vehicle for 30 days. Liver and kidney injury were measured by plasma ALT and BUN, respectively, and by histopathology. Tissue regeneration was assessed by 3H-thymidine incorporation into hepato- and nephro-nuclear DNA and by proliferating cell nuclear antigen staining. In addition, GSH and CYP2E1 in liver and kidney were assessed at selected time points. The levels of chloroform were measured in blood, liver, and kidney during the dosing regimen (1, 7, 14, and 30 days). Kidney injury was evident after 1 day with all three doses and sustained until 7 days followed by complete recovery. Mild to moderate liver injury was observed from 1 to 14 days with all three dose levels followed by gradual decrease. Significantly higher regenerative response was evident in liver and kidney at 7 days, but the response was robust in kidney, preventing progression of injury beyond first week of exposure. While the kidney regeneration reached basal levels by 21 days, moderate liver regeneration with two higher doses sustained through the end of the dosing regimen and 3 days after that. Following repeated exposure for 7, 14, and 30 days, the blood and tissue levels of chloroform were substantially lower with all three dose levels compared to the levels observed with single exposure. Increased exhalation of 14C-chloroform after repeated exposures explains the decreased chloroform levels in circulation and tissues. These results suggest that toxicokinetics and toxicodynamics (tissue regeneration) contribute to the tolerance observed in SW mice to subchronic chloroform toxicity. Neither bioactivation nor detoxification

  7. Abiotic degradation rates for carbon tetrachloride and chloroform: Final report.

    Energy Technology Data Exchange (ETDEWEB)

    Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Humphrys, Daniel R.; Wietsma, Thomas W.; Truex, Michael J.

    2012-12-01

    This report documents the objectives, technical approach, and progress made through FY 2012 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The project also sought to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. We conducted 114 hydrolysis rate experiments in sealed vessels across a temperature range of 20-93 °C for periods as long as 6 years, and used the Arrhenius equation to estimate activation energies and calculate half-lives for typical Hanford groundwater conditions (temperature of 16 °C and pH of 7.75). We calculated a half-life of 630 years for hydrolysis for CT under these conditions and found that CT hydrolysis was unaffected by contact with sterilized, oxidized minerals or Hanford sediment within the sensitivity of our experiments. In contrast to CT, hydrolysis of CF was generally slower and very sensitive to pH due to the presence of both neutral and base-catalyzed hydrolysis pathways. We calculated a half-life of 3400 years for hydrolysis of CF in homogeneous solution at 16 °C and pH 7.75. Experiments in suspensions of Hanford sediment or smectite, the dominant clay mineral in Hanford sediment, equilibrated to an initial pH of 7.2, yielded calculated half-lives of 1700 years and 190 years, respectively, at 16 °C. Experiments with three other mineral phases at the same pH (muscovite mica, albite feldspar, and kaolinite) showed no change from the homogeneous solution results (i.e., a half-life of 3400 years). The strong influence of Hanford sediment on CF hydrolysis was attributed to the presence of smectite and its ability to adsorb protons, thereby buffering the solution pH at a higher level than would otherwise occur. The project also determined liquid-vapor partition coefficients for CT under the temperatures and pressures encountered in the sealed vessels that

  8. ADSORPTION OF CHLOROFORM AND TRICHLOROETHYLENE IN WATER WITH A NEW KIND OF HYPERCROSSLINKED RESINS

    Institute of Scientific and Technical Information of China (English)

    Zheng-hao Fei; Jin-long Chen; Guan-dao Gao; Chao Long; Ai-min Li; Quan-xing Zhang

    2004-01-01

    In this paper two newly developed hypercrosslinked resins were used to treat micropolluted drinking water and their static and kinetic adsorption were investigated at 293 K. The results show that these two adsorbents are superior to Amberlite XAD-4 for removing chloroform and trichloroethylene in aqueous solutions. The breakthrough capacity and the total capacities from mini-column adsorption studies for chloroform and trichloroethylene on XAD-4, ZH-01 and ZH-00 are calculated respectively under experimental conditions

  9. Hot spot formation of chloroform in forest soils caused pollution of groundwater

    Science.gov (United States)

    Jacobsen, Ole S.; Albers, Christian N.; Laier, Troels; Hunkeler, Daniel

    2015-04-01

    High concentration of chloroform in groundwater is usually attributed to anthropogenic input, but we have found that the groundwater beneath some pristine areas contained chloroform from 1 - 10 µg/L. Groundwater containing chloroform that exceeds 1 µg/L could not be used for drinking water according to Danish regulations. The strict demands on groundwater quality may have to be taken into account when decisions are made regarding the change of land use in order to protect major recharge areas from pollution with nitrate and pesticides resulting from high-yield agriculture production. The terrestrial environment and especially hot spots in forest soils seem to be important contributors to apparent pollution of groundwater with chloroform. We performed a field study to investigate concentration and fluxes of chloroform to the groundwater from in four coniferous forests in order to increase knowledge on the hot spot formation and fate of natural chloroform. We investigated four stations over a period of several years in order to measure the net-formation of chloroform. Field measurements soil air concentrations of chloroform were monitored in five soil profiles down to the groundwater table. Meteorological data were recorded at all stations In the hotspots up to 120 ppbv was found in soil air under the spruce forest, to be compared to an ambient atmospheric concentration of 0.02 ppbv. The concentration of chloroform in soil air showed seasonal variation with a maximum in August-September. The chloroform concentration decreased with depth in all profiles during the summer half-year to about 20 % of concentration in the production layer. However, the concentration is still high enough to give an equilibrium concentration in the upper groundwater of 1-10 µg/L. Stable carbon isotopic analyses of chloroform from the uppermost groundwater in different parts of the forests and from soil water showed values from δ13C = -13 ‰ to -27 ‰, corresponding to the ratio in

  10. Characterization of hot spots for natural chloroform formation: Relevance for groundwater quality

    Science.gov (United States)

    Jacobsen, Ole S.; Albers, Christian N.; Laier, Troels

    2015-04-01

    Chloroform soil hot spot may deteriorate groundwater quality and may even result in chloroform concentration exceeding the Danish maximum limit of 1 µg/L in groundwater for potable use. In order to characterize the soil properties important for the chloroform production, various ecosystems were examined with respect to soil air chloroform and soil organic matter type and content. Coniferous forest areas, responsible for highest chloroform concentrations, were examined on widely different scales from km to cm scale. Furthermore, regular soil gas measurements including chloroform were performed during 4 seasons at various depths, together with various meteorological measurements and soil temperature recordings. Laboratory incubation experiments were also performed on undisturbed soil samples in order to examine the role of various microbiota, fungi and bacteria. To identify hot spots responsible for the natural contamination we have measured the production of chloroform in the upper soil from different terrestrial systems. Field measurements of chloroform in top soil air were used as production indicators. The production was however not evenly distributed at any scale. The ecosystems seem to have quite different net-productions of chloroform from very low in grassland to very high in some coniferous forests. Within the forest ecosystem we found large variation in chloroform concentrations depending on vegetation. In beech forest we found the lowest values, somewhat higher in an open pine forest, but the highest concentrations were detected in spruce forest without any vegetation beneath. Within this ecotype, it appeared that the variation was also large; hot spots with 2-4 decades higher production than the surrounding area. These hot spots were not in any way visually different from the surroundings and were of variable size from 3 to 20 meters in diameter. Besides this, measurements within a seemingly homogenous hot spot showed that there was still high

  11. Removal of Chloroform (CHCl3 from Tehran Drinking Water by GAC and Air Stripping Columns

    Directory of Open Access Journals (Sweden)

    M T Samadi, S Nasseri, A Mesdaghinia, M R Alizadefard

    2004-07-01

    Full Text Available The harmful substances, defined as trihalomethanes (THMs, were found to be formed during the disinfection of drinking water when chlorine was used as the disinfectant. In this research, the effectiveness of granular activated carbon (GAC and air stripping (AS packed column for the removal of chloroform (CHCl3 (as THMs basic indicator compound in many resources in range of 50 to300µg/L, from drinking water was studied. Pilots of GAC and air stripping columns were designed and set up. The study was carried out for the two cases of deionized and chlorinated Tehran tap water. Also the effects of flow rate, chloroform and TDS concentrations were considered in both treatment systems. Gas chromatography (GC with electron capture detector (ECD was used for determination of chloroform concentration in inlet and outlet samples. The obtained data were analyzed by SPSS and non-parametric Kruskal–Wallis method. Results showed a positive correlation between the flow rate and chloroform concentration, and removal efficiencies. The average of variations of removal efficiencies for AS and GAC columns with deionized water samples were, 89.9%, 71.2% and for chlorinated Tehran tap water were 91.2% and 76.4%, respectively. The removal of feed residual chlorine in these columns with 0.5, 0.8 ppm was 100%, respectively and re-chlorination for finishing water was recommended. Results showed AS to be considered more effective in chloroform removal for conventional water treatment plants as a finishing process.

  12. The Faraday effect revisited

    DEFF Research Database (Denmark)

    Cornean, Horia; Nenciu, Gheorghe

    2009-01-01

    This paper is the second in a series revisiting the (effect of) Faraday rotation. We formulate and prove the thermodynamic limit for the transverse electric conductivity of Bloch electrons, as well as for the Verdet constant. The main mathematical tool is a regularized magnetic and geometric...

  13. A Hydrostatic Paradox Revisited

    Science.gov (United States)

    Ganci, Salvatore

    2012-01-01

    This paper revisits a well-known hydrostatic paradox, observed when turning upside down a glass partially filled with water and covered with a sheet of light material. The phenomenon is studied in its most general form by including the mass of the cover. A historical survey of this experiment shows that a common misunderstanding of the phenomenon…

  14. In Vitro Antioxidant and Enzymes Inhibitory activity of Chloroform Fraction of Hydroalcoholic extract obtained from Argemone mexicana

    Directory of Open Access Journals (Sweden)

    Nayak P

    2013-03-01

    Full Text Available In the present investigation antioxidant and alphaamylase inhibitory activity of chloroform fraction of Argemone mexicana were evaluated. The antioxidant activity of chloroform fraction of A. mexicana was evaluated by DPPH, Super oxide radical Scavenging activity, ABTS radical cation scavenging activity and Nitric oxide radical scavenging activity. Alpha-amylase inhibitory activity of chloroform fraction was evaluated by DNS method respectively. The observed resultant antioxidant activity of chloroform fraction in all studied models was moderate as compared with reference standard Ascorbic acid. The chloroform fraction exhibited appreciable α-amylase inhibitory activity with an IC50 value 48.92μg/ml respectively, when compared with acarbose (IC50 value 83.33μg/ml.In conclusion, from the results of present study it is confirmed that antioxidant and alpha-amylase inhibitory activity of chloroform fraction of A. mexicana may contribute in its earlier observed antidiabetic potential.

  15. Atomistic study of lipid membranes containing chloroform: looking for a lipid-mediated mechanism of anesthesia.

    Directory of Open Access Journals (Sweden)

    Ramon Reigada

    Full Text Available The molecular mechanism of general anesthesia is still a controversial issue. Direct effect by linking of anesthetics to proteins and indirect action on the lipid membrane properties are the two hypotheses in conflict. Atomistic simulations of different lipid membranes subjected to the effect of small volatile organohalogen compounds are used to explore plausible lipid-mediated mechanisms. Simulations of homogeneous membranes reveal that electrostatic potential and lateral pressure transversal profiles are affected differently by chloroform (anesthetic and carbon tetrachloride (non-anesthetic. Simulations of structured membranes that combine ordered and disordered regions show that chloroform molecules accumulate preferentially in highly disordered lipid domains, suggesting that the combination of both lateral and transversal partitioning of chloroform in the cell membrane could be responsible of its anesthetic action.

  16. Acute liver injury in two workers exposed to chloroform in cleanrooms: a case report.

    Science.gov (United States)

    Kang, Young Joong; Ahn, Jungho; Hwang, Yang-In

    2014-01-01

    We report 2 cases of hepatotoxicity in cleanroom workers due to high retained chloroform air concentrations. The women, aged 34 and 41 years, who had been working in a medical endoscopic device manufacturer as cleanroom workers for approximately 40-45 days suffered severe liver damage. Two measured time-weighted averages of the chloroform concentration in the air in the cleanroom were 82.74 and 64.24 ppm, which are more than 6 times the legal occupational exposure limit in Korea. Only 7% of the cleanroom air was newly introduced from outside. The clinical courses of these cases and workplace inspection, led us to conclude that both cases of hepatotoxicity were caused by chloroform exposure.

  17. A study of the sources and sinks of methane and methyl chloroform using a global three-dimensional Lagrangian tropospheric tracer transport model

    OpenAIRE

    Taylor, JA; Brasseur, GP; Zimmerman, PR; Cicerone, RJ

    1991-01-01

    By comparison with methyl chloroform observations a global average tropospheric hydroxyl radical concentration of 6.4 × 105 cm-3 was found to be consistent with published methyl chloroform emission data for the year 1980. Published methyl chloroform emissions data for 1981-1984 were found to be inconsistent with the observed methyl chloroform concentration increases. Using the hydroxyl radical field calibrated to the methyl chloroform observations, two source function models of the spatial an...

  18. Mechanistic insights into the formation of chloroform from natural organic matter using stable carbon isotope analysis

    Science.gov (United States)

    Breider, Florian; Hunkeler, Daniel

    2014-01-01

    Chloroform can be naturally formed in terrestrial environments (e.g. forest soils, peatland) by chlorination of natural organic matter (NOM). Recently, it was demonstrated that natural and anthropogenic chloroform have a distinctly different carbon isotope signature that makes it possible to identify its origin in soil and groundwater. In order to evaluate the contribution of different functional groups to chloroform production and factors controlling the isotopic composition of chloroform, carbon isotope trends during chlorination of model compounds, soil organic matter (SOM) and humic acids were evaluated, and apparent kinetic isotope effects (AKIEs) quantified. Phenol and propanone were selected as model compounds representing common functional groups in NOM. Chlorination was induced by hypochlorous acid to mimic natural chlorination. The pH ranged between 4 and 8 to cover typical soil conditions. For each model compound and pH, different AKIEs were observed. For phenol, the AKIE was normal at pH 4 (1.0156 ± 0.0012) and inverse at pH 8 (0.9900 ± 0.0007). For 2-propoanol, an opposite pH dependence was observed with an inverse AKIE at pH 4 (0.9935 ± 0.0007) and a normal AKIE at pH 8 (1.0189 ± 0.0016). The variations of the AKIE values suggest that the rate-limiting step of the reaction is either the re-hybridization of the carbon atom involved in chloroform formation or the hydrolysis of trichloroacetyl intermediates depending on the nature of functional group and pH. The chloroform formation from humic acid and SOM gives rise to small isotope variations. A comparison of the isotopic trends of chloroform formed from humic acid and SOM with those found for the model compounds suggest that opposed AKIE associated with the chlorination of phenolic and ketone moieties of NOM partly compensate each other during chlorination of NOM indicating that different types of functional groups contribute to chloroform formation.

  19. Modeling the interaction of ozone with chloroform and bromoform under conditions close to stratospheric

    Science.gov (United States)

    Strokova, N. E.; Yagodovskaya, T. V.; Savilov, S. V.; Lukhovitskaya, E. E.; Vasil'ev, E. S.; Morozov, I. I.; Lunin, V. V.

    2013-02-01

    The reactions of ozone with chloroform and bromoform are studied using a flow gas discharge vacuum unit under conditions close to stratospheric (temperature range, 77-250 K; pressure, 10-3-0.1 Torr in the presence of nitrate ice). It is shown that the reaction with bromoform begins at 160 K; the reaction with chloroform, at 190 K. The reaction products are chlorine and bromine oxides of different composition, identified by low-temperature FTIR spectroscopy. The presence of nitrate ice raises the temperature of reaction onset to 210 K.

  20. Remembered Experiences and Revisit Intentions

    DEFF Research Database (Denmark)

    Barnes, Stuart; Mattsson, Jan; Sørensen, Flemming

    2016-01-01

    path modelling, we examine the impact of positive affect tourist experiences on the development of revisit intentions. We find that longer-term remembered experiences have the strongest impact on revisit intentions, more so than predicted or immediate memory after an event. We also find that remembered...

  1. Deterministic Graphical Games Revisited

    DEFF Research Database (Denmark)

    Andersson, Daniel; Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro;

    2008-01-01

    We revisit the deterministic graphical games of Washburn. A deterministic graphical game can be described as a simple stochastic game (a notion due to Anne Condon), except that we allow arbitrary real payoffs but disallow moves of chance. We study the complexity of solving deterministic graphical...... games and obtain an almost-linear time comparison-based algorithm for computing an equilibrium of such a game. The existence of a linear time comparison-based algorithm remains an open problem.......We revisit the deterministic graphical games of Washburn. A deterministic graphical game can be described as a simple stochastic game (a notion due to Anne Condon), except that we allow arbitrary real payoffs but disallow moves of chance. We study the complexity of solving deterministic graphical...

  2. Fossil turbulence revisited

    CERN Document Server

    Gibson, C H

    1999-01-01

    A theory of fossil turbulence presented in the 11th Liege Colloquium on Marine turbulence is "revisited" in the 29th Liege Colloquium "Marine Turbulence Revisited". The Gibson (1980) theory applied universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as it is constrained and fossilized by buoyancy forces. Towed oceanic microstructure measurements of Schedvin (1979) confirmed the predicted universal constants. Universal constants, spectra, hydrodynamic phase diagrams (HPDs) and other predictions of the theory have been reconfirmed by a wide variety of field and laboratory observations. Fossil turbulence theory has many applications; for example, in marine biology, laboratory and field measurements suggest phytoplankton species with different swimming abilities adjust their growth strategies differently by pattern recognition of several days of turbulence-fossil-turbulence dissipation and persistence times above thres...

  3. 'My beloved chloroform'. Attitudes to childbearing in colonial Queensland: a case study.

    Science.gov (United States)

    Woolcock, H R; Thearle, M J; Saunders, K

    1997-12-01

    In 1847 the anaesthetic and analgesic properties of chloroform were discovered. This technology generated a new era for midwifery: mothers could be relieved of pain in childbirth. The introduction of chloroform for childbirth saw increasing medical dominance in obstetrics, traditionally in the hands of the midwife. At the same time the use of chloroform sparked a medical and moral controversy which lasted for several decades. On the one hand women were destined by the 'curse of Eve' to experience pain during childbirth; on the other, medical humanitarians and practitioners believed that there were technical and moral reasons for alleviating pain in childbirth. In concentrating on the debate historians have largely ignored the reactions of mothers to the introduction of the technology. This paper explores changing attitudes to childbearing within the context of colonial Queensland society, 1860-90, by examining the correspondence of an upper-class mother. Her education and liberal outlook, and a certain ambivalence towards motherhood, all influenced her attitude to the use of chloroform and the process of childbirth. PMID:11619827

  4. Persulfate Oxidation of MTBE- and Chloroform-Spent Granular Activated Carbon

    Science.gov (United States)

    Activated persulfate (Na2S2O8) regeneration of methyl tert-butyl ether (MTBE) and chloroform-spent GAC was evaluated in this study. Thermal-activation of persulfate was effective and resulted in greater MTBE removal than either alkaline-activation or H2O2–persulfate binary mixtur...

  5. Chemical changes in the chloroform-paraffin system irradiated by 60Co gamma-rays, 1

    International Nuclear Information System (INIS)

    It has been reported that the chloroform-paraffin-dye system have excellent sensitivity for radiation as a solid chemical dosimeter or a phantom. However, the chemical changes in the irradiated system are not examined in detail. In the present study, the effect of paraffin on changes in the above system of a liquid state irradiated by 60Co γ-rays was examined by using various normal paraffin, and the other variable factors on the changes were done. When the chloroform solution and the solution containing 25 per cent of paraffin by volume with 5.0 x 15-5 mol/liter of Methyl Yellow as a dye were irradiated by 2000 R, G values for the formation of hydrogen chloride in the both solutions were 8.4 and 10.8, respectively, and were little affected by the kind of those, from C6 (hexane) to C36 (hexatria-contane). These results suggest that chlorine radical formed by radiolysis of chloroform may react with hydrogen atom from paraffin, thereby increasing the amount of hydrogen chloride. Presence of oxygen increased G value of the chloroform solution from 7.6 to 8.4, but did little that of the solution containing paraffin. (author)

  6. "Comparison of Nanofiltration and GAC Adsorption Processes for Chloroform Removal from Drinking Water"

    Directory of Open Access Journals (Sweden)

    S Nasseri

    2004-08-01

    Full Text Available In this research, the Chloroform (CHCl3 removal effectiveness of two water treatment systems including membrane technology and granular activated carbon (GAC adsorption were studied. Two bench-scales were designed and set up: 1 Nanofiltration (NF spiral-wound modules and 2 GAC adsorption column. Chloroform was considered as trihalomethanes (THMs basic indicator compound. The inlet and outlet CHCl3 concentrations were detected by gas chromatography (GC with electron capture detector (ECD. The study was carried out for the two cases of spiked deionized water with CHCl3 and chlorinated Tehran tap water. Flow rate, CHCl3 and total dissolved solids (TDS concentrations were considered in both treatment systems and the transmembrane pressures for membrane pilot, as the basic variables affecting removal efficiencies. Results showed that CHCl3 rejection coefficients for NF 300 Da, NF 600 Da and GAC Column, with various operation conditions had a range of 55.2% to 87.8%, 78% to 85% and 41.4% to 74.1%, respectively. It was found that removal efficiencies for NF 600 Da were lower than those of NF 300 Da and GAC column. The obtained data were analyzed by SPSS and non-parametric Kruskal-Wallis method. Results showed a positive correlation between the flow rate, CHCl3 concentration and chloroform rejection coefficients and the TDS concentration had no significant effect on chloroform removal efficiencies.

  7. Reverse cholesterol transport revisited

    Institute of Scientific and Technical Information of China (English)

    Astrid; E; van; der; Velde

    2010-01-01

    Reverse cholesterol transport was originally described as the high-density lipoprotein-mediated cholesterol flux from the periphery via the hepatobiliary tract to the intestinal lumen, leading to fecal excretion. Since the introduction of reverse cholesterol transport in the 1970s, this pathway has been intensively investigated. In this topic highlight, the classical reverse cholesterol transport concepts are discussed and the subject reverse cholesterol transport is revisited.

  8. The bar instability revisited

    OpenAIRE

    Chiodi, Filippo; Andreotti, Bruno; Claudin, Philippe

    2012-01-01

    The river bar instability is revisited, using a hydrodynamical model based on Reynolds averaged Navier-Stokes equations. The results are contrasted with the standard analysis based on shallow water Saint-Venant equations. We first show that the stability of both transverse modes (ripples) and of small wavelength inclined modes (bars) predicted by the Saint-Venant approach are artefacts of this hydrodynamical approximation. When using a more reliable hydrodynamical model, the dispersion relati...

  9. Oxidative phosphorylation revisited

    DEFF Research Database (Denmark)

    Nath, Sunil; Villadsen, John

    2015-01-01

    The fundamentals of oxidative phosphorylation and photophosphorylation are revisited. New experimental data on the involvement of succinate and malate anions respectively in oxidative phosphorylation and photophosphorylation are presented. These new data offer a novel molecular mechanistic...... are proton‐dicarboxylic acid anion cotransporters and not simply electrogenic proton translocators. These results necessitate revision of previous theories of biological energy transduction, coupling, and ATP synthesis. The novel molecular mechanism is extended to cover ATP synthesis in prokaryotes...

  10. Detection of chloroform in water using an azo dye-modified β-cyclodextrin - Epichlorohydrin copolymer as a fluorescent probe

    Science.gov (United States)

    Ncube, Phendukani; Krause, Rui W. M.; Mamba, Bhekie B.

    Chlorination disinfection by-products (DBPs) in water pose a health threat to humans and the aquatic environment. Their detection in water sources is therefore vital. Herein we present the detection of chloroform, a DBP, using a molecular fluorescent probe. The detection was based on the quenching of fluorescence of the probe by chloroform due to host-guest complex formation between β-cyclodextrin in the probe and the chloroform molecule. The stability constant for the host-guest complex was high at 3.825 × 104 M-1. Chloroform quenched the fluorescence of the copolymer the most compared to the other small chlorinated compounds studied, suggesting that the probe was more sensitive to chloroform, with a sensing factor of 0.35 compared to as low as 0.0073 for dichloromethane. There was no interference from other chloroalkanes on the quenching efficiency of chloroform. The probe was used to detect chloroform in dam water as well as in bottled water. Detection of chloroform in both water samples using the probe was possible without chemically treating the water samples which may introduce other pollutants.

  11. Reframing in dentistry: revisited.

    Science.gov (United States)

    Nuvvula, Sivakumar; Kamatham, Rekalakshmi; Challa, Ramasubbareddy; Asokan, Sharath

    2013-01-01

    The successful practice of dentistry involves a good combination of technical skills and soft skills. Soft skills or communication skills are not taught extensively in dental schools and it can be challenging to learn and at times in treating dental patients. Guiding the child's behavior in the dental operatory is one of the preliminary steps to be taken by the pediatric dentist and one who can successfully modify the behavior can definitely pave the way for a life time comprehensive oral care. This article is an attempt to revisit a simple behavior guidance technique, reframing and explain the possible psychological perspectives behind it for better use in the clinical practice. PMID:24021326

  12. Analogue Magnetism Revisited

    CERN Document Server

    Osano, Bob

    2016-01-01

    In this article we revisit the significance of the often debated structural similarity between the equations of electromagnetism and fluid dynamics. Although the matching of the two sets of equations has successfully been done for non-dissipative forms of the equations, little has been done for cases where the dissipative terms are non-negligible. We consider the consequence of non-negligible viscosity and diffusivity, and how the fine-tuning of these parameters could allow fluid dynamics to be used to indirectly study certain properties of magnetic fields.

  13. GC-MS/MS Based Identification of Bioactive principles of Chloroform fraction of Swertia Chirayatia (Chirata.

    Directory of Open Access Journals (Sweden)

    Homa Jilani Khan

    2016-05-01

    Full Text Available The aim of this study is to characterize the chemical composition, in vitro antioxidant and anticancer activity of chloroform fraction of Swertia chirata L. (Family Gentianaceae. GC-MS analysis of chloroform fraction of S. chirata (CFSc identified twenty-five compounds belonging to different chemical class. Among these important classes of compounds were tri-terpenoids, phenol, acids, and fatty acids. Our phytochemical analysis of CFSc was well supported by its Total Phenolic Content and antioxidant activity with in vitro anticancer activity which was evaluated by MTT assay also showed that CFSc exhibited anti-proliferative activity against human breast cancer cell lines (MDA-MB-231 and MCF-7. In conclusion; our study revealed an extensive biochemical profile of CFSc as well its potential as a pharmacological agent with respect of its antioxidant and anti-cancer property. More safety and toxicological studies are needed to be addressed to ensure the use of CFSc for medicinal purposes.

  14. A very stable complex of a modified marine cyclopeptide with chloroform

    Science.gov (United States)

    Haberhauer, Gebhard; Pintér, Áron; Woitschetzki, Sascha

    2013-12-01

    Noncovalent interactions play a pivotal role in molecular recognition. These interactions can be subdivided into hydrogen bonds, cation-π interactions, ion pair interactions and London dispersion forces. The latter are considered to be weak molecular interactions and increase with the size of the interacting moieties. Here we show that even the small chloroform molecule forms a very stable complex with a modified marine cyclopeptide. By means of high-level quantum chemical calculations, the size of the dispersive interactions is calculated; the dispersion energy (approximately -40 kcal mol-1) is approximately as high as if the four outer atoms of the guest form four strong hydrogen bonds with the host. This strong binding of chloroform to a modified marine cyclopeptide allows the speculation that the azole-containing cyclopeptides-haloform interaction may play some biological role in marine organisms such as algae.

  15. Study on the Electrical Conductivity of Au Nanoparticle/ Chloroform and Toluene Suspensions

    Institute of Scientific and Technical Information of China (English)

    FANG Fang; ZHANG Ya-fei

    2005-01-01

    Au nanoparticles capped by hexadecanethiol and dodecanethiol were chemically synthesized. The characteristics of electrical conductivity for the capped nanoparticles dissolved in chloroform and toluene solvents were investigated. The electrical conductivity of the samples is conspicuously Au nanoparticle concentration dependent.The results show that a rapid conductivity increases when the nanoparticle concentration increases from low value to a moderate value of 5.47 g/L and 11.22 g/L, which is capped by hexadecanethiol and dodecanethiol in chloroform solvent, and 2.77 g/L and 7.88 g/L in toluene solvent. The room-temperature dc conductivity σdc of Au nanoparticle capped by hexadecanethiol is smaller than that capped by dodecanethiol in the whole range of Au nanoparticle concentrations. The conductivity of Au nanoparticle suspensions increases almost linearly in the temperature range in above two solvents.

  16. Surface Properties of Photocatalytic Nano-Crystalline Titania Films and Reactor for Photocatalytic Degradation of Chloroform

    DEFF Research Database (Denmark)

    Søgaard, Erik Gydesen; Simonsen, Morten Enggrob; Jensen, Henrik;

    2006-01-01

    concentration chloroform of 7 mg/l was degraded in a period of 500 hour. The kinetics of the degradation of chloroform in the flow reactor was found to obey Langmuir-Hinshelwood kinetics. The investigation also showed that the reactor design has a significant influence on the rate of degradation...... is the limiting condition for the rate of reaction. Also a new type of continuous photoreactor was developed in which the TiO2 catalyst made from Sol-gel film was immobilized on the surface of quartz tubes surrounding the UV lamps and on the internal surface of the reactor walls. The study showed that an initial......, as it was observed that the position of the coated lamp in the reactor yield different degradation rates....

  17. Analysis of phenolic acids as chloroformate derivatives using solid phase microextraction-gas chromatography.

    Science.gov (United States)

    Citová, Ivana; Sladkovský, Radek; Solich, Petr

    2006-07-28

    In the presented study, a simple and original procedure of phenolic acids derivatization treated by ethyl and methyl chloroformate performed in an aqueous media consisting of acetonitrile, water, methanol/ethanol and pyridine has been modified and optimized. Seven phenolic acid standards-caffeic, ferulic, gallic, p-coumaric, protocatechuic, syringic and vanillic were derivatized into corresponding methyl/ethyl esters and subsequently determined by the means of gas chromatography connected to the flame-ionisation detector (FID). Some selected validation parameters as linearity, detection and quantitation limits and peak area repeatability were valued. The total time of gas chromatography (GC) analysis was 24 min for methyl chloroformate and 30 min for ethyl chloroformate derivatization. The more suitable methyl chloroformate derivatization was used for further experiments on the possibility of multiple pre-concentration by the direct solid phase microextraction technique (SPME). For this purpose, polyacrylate (PA), polydimethylsiloxane (PDMS), carboxen/polydimethylsiloxane (CAR/PDMS) and polydimethylsiloxane/divinylbenzene (PDMS/DVB) fibres were tested and the extraction conditions concerning time of extraction, temperature and time of desorption were optimized. The most polar PA fibre gave the best results under optimal extraction conditions (50 min extraction time, 25 degrees C extraction temperature and 10 min desorption time). As a result, the total time of SPME-GC analysis was 74 min and an increase in method sensitivity was reached. The limits of quantitation (LOQ) of p-coumaric, ferulic, syringic and vanillic acid esters after SPME pre-concentration were 0.02, 0.17, 0.2 and 0.2 microg mL(-1), respectively, showing approximately 10 times higher sensitivity in comparison with the original GC method. PMID:17723529

  18. Comparative analysis of antioxidant and phenolic content of chloroform extract/fraction of Terminalia chebula

    OpenAIRE

    Walia, Harpreet; Kumar, Subodh; Arora, Saroj

    2011-01-01

    In the present study, two chloroform extracts of fruits of Terminalia chebula viz. “CHL1” and “CHL 2” prepared by maceration and sequential method respectively was compared for their antioxidant efficacy and phenolic content. The extraction procedure of plant material plays an important role in the activity of phytochemicals. Also, the assessment of antioxidant capacity of phytochemicals cannot be executed precisely by any single method due to complex nature of phytochemicals as multiple reac...

  19. Chloroform in a pristine aquifer system: Toward an evidence of biogenic origin

    DEFF Research Database (Denmark)

    Laturnus, F.; Lauritsen, F.R.; Grøn, C.

    2000-01-01

    Ambient air, soil air, and groundwater were monitored for volatile halogenated organic compounds in a pristine spruce forest at Klosterhede, Denmark. Although this location is remote from industrial areas and free of any point sources of either soil or groundwater contamination, several volatile......, only bromoform was found and only in the upper soil layer. For chloroform a formation in the spruce forest soil is suggested, leading to concentrations in the groundwater in the micrograms per liter range....

  20. Cytotoxicity activities of chloroform extract of Cichorium intybus seed against HCT-15 and Vero cell line

    OpenAIRE

    Prashant Y Mali

    2015-01-01

    Background: Cichorium intybus L., (Asteraceae) is well-known as a coffee substitute but is also widely used medicinally to treat various ailments ranging from wounds to diabetes. Other plant parts are also used for liver and cancer disorder. Objective: The objective was to study the cytotoxic potential of chloroform extract of C. intybus seed against HCT-15 and Vero (normal) cell line. Materials and Methods: Fourier transform infrared spectroscopy (FTIR) analysis of the extract was performed....

  1. Cytotoxicity activities of chloroform extract of Cichorium intybus seed against HCT-15 and Vero cell line

    Directory of Open Access Journals (Sweden)

    Prashant Y Mali

    2015-01-01

    Full Text Available Background: Cichorium intybus L., (Asteraceae is well-known as a coffee substitute but is also widely used medicinally to treat various ailments ranging from wounds to diabetes. Other plant parts are also used for liver and cancer disorder. Objective: The objective was to study the cytotoxic potential of chloroform extract of C. intybus seed against HCT-15 and Vero (normal cell line. Materials and Methods: Fourier transform infrared spectroscopy (FTIR analysis of the extract was performed. 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyl tetrazolium bromide assay was used for evaluation of the cytotoxic potential of chloroform extract of C. intybus seed. Doxorubicin was considered as standard reference drug. The concentrations 1000–0.05 μg/ml was used in the experiment. Result and Discussion: FTIR spectrum showed 1025.363, 1083.126, 1291.366, 1389.144, and 1569.294 peaks/centers in the wavelength region of 4,000.00–650.00 cm−1. The chloroform extract of C. intybus seed and doxorubicin was showed 1411.37 μg/ml and 460.13 μg/ml 50% cell growth inhibition (IC50 against the HCT-15 cell line. Both extract and doxorubicin were safe against the Vero (normal cell line. Conclusion: It can be concluded that the chloroform extract of C. intybus seed was not efficient against the HCT-15 cell line at the concentrations used in the experiment. Furthermore, there is no need to explore the said studies by in vivo models.

  2. Telomerization of Vinyl Chloride with Chloroform Initiated by Ferrous Chloride-Dimethylacetamide under Ultrasonic Conditions

    Directory of Open Access Journals (Sweden)

    Hua Qian

    2015-01-01

    Full Text Available Telomerization of vinyl chloride with chloroform was investigated using ferrous chloride-dimethylacetamide system, and 42.1% yield, more than four times the one reported before, was achieved. The addition of ultrasound further improved the reaction and yield was raised to 51.9% with trace byproducts at highly reduced reaction time and temperature. Ferrous chloride-dimethylacetamide under ultrasonic irradiation acts as a very efficient catalyst system for the 1 : 1 telomerization.

  3. Evidence of Hydrogen Bonding in Chloroform and Polyacrylates from NMR Measurements

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The presence of hydrogen bonding in chloroform and polyacrylate mixtures was demonstrated by observation of 1H- and 13C-NMR chemical shifts. Comparison of the nuclear magnetic resonance (NMR) chemical shift in polymer solutions with their low molecular mass analogues showed the effect of steric hindrance on hydrogen bonding. This initial investigation is helpful for understanding the intermolecular interaction in relatively weak hydrogen bonding polymer solutions.

  4. Effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin.

    Directory of Open Access Journals (Sweden)

    Sedigheh Khedmat

    2015-02-01

    Full Text Available This study aimed to assess the effect of chloroform, eucalyptol and orange oil solvents on the microhardness of human root dentin.Sixty-eight single-rooted single-canal extracted human premolar teeth were used. Tooth crowns were separated from the roots at the cementoenamel junction (CEJ. Roots were buccolingually sectioned into mesial and distal halves. Specimens were randomly divided into 5 groups, with 20 teeth in each solvent group and 4 teeth in each control group. Primary microhardness of specimens was measured using Vickers microhardness tester. Specimens were exposed to solvents for 15 minutes and were subjected to microhardness testing again. Data were recorded and analyzed using repeated measure ANOVA.No significant difference was found in dentin microhardness before and after exposure to solvents in any of the orange oil, eucalyptol, chloroform or saline groups (P=0.727. None of the experimental groups showed any significant difference in terms of dentin microhardness reduction (P=0.99 and had no significant difference with the negative control group.This study showed that chloroform, eucalyptol and orange oil as gutta percha solvents did not decrease the microhardness of root dentin. Thus, none of the mentioned solvents has any superiority over the others in terms of affecting dentin properties.

  5. Vapor-liquid equilibria for acetone + chloroform + methanol and constituent binary systems at 101. 3 kPa

    Energy Technology Data Exchange (ETDEWEB)

    Hiaki, Toshihiko (Nihon Univ., Chiba (Japan). Dept. of Industrial Chemistry); Kurihara, Kiyofumi; Kojima, Kazuo (Nihon Univ., Tokyo (Japan). Dept. of Industrial Chemistry)

    1994-10-01

    Vapor-liquid equilibria (VLE) and azeotropic data, which are useful for the design and operation of separation processes, have been observed for many systems. Isobaric vapor-liquid equilibria for acetone + chloroform + methanol and for the constituent binary systems chloroform + methanol and chloroform + acetone were measured at 101.3 kPa using a liquid-vapor ebullition-type equilibrium still. The experimental data were correlated with the extended Redlich-Kister and Wilson equations. The data were best correlated and completely calculated for the ternary and three binary azeotropic data using the extended Redlich-Kister equation.

  6. Anti-diabetic potential of chloroform extract of flowers of Calotropis gigantea: An in vitro and in vivo study

    OpenAIRE

    N K Choudhary; Jha, A. K.; Sharma, S.; Goyal, S.; J Dwivedi

    2011-01-01

    The chloroform extract of Calotropis gigantea flowers was evaluated for anti-diabetic activity in alloxan-induced hyperglycemia in vivo and inhibition of α-amylase and α-glucosidase in vitro. It was also intended to establish correlation between the serum marker antioxidant enzymes and diabetes. Diabetes was induced by a single intraperitoneal injection of alloxan monohydrate freshly prepared in a dose of 150 mg/kg. Chloroform extract showing presence of flavonoids was administered orally at ...

  7. The effect of silver nitrate, chloroformic garlic extract and normal saline in induction of sclerosing cholangitis in rabbits

    International Nuclear Information System (INIS)

    Objective was to the effects of 0.5% silver nitrate, 20% chloroformic garlic extract and 0.9% normal saline in induction of sclerosing cholangitis in the bile ducts of rabbits. During a 6-months period from April to September 2006 in Shiraz University Laboratory Animal Research Center, we selected 3 equal groups of rabbits. We injected 0.5% silver nitrate, 20% chloroformic garlic extract and 0.9% normal saline into the bile ducts of each group. The animals were euthanized and autopsied after 4 months and the liver and bile ducts were removed and studied histopathologically. Cholangiography was undertaken to evaluate the presence and extent of any sclerosing cholangitis. Animals showed sclerosing cholangitis in silver nitrate group (7 [58%]), one (8%) in chloroformic garlic extract group and one (7%) in normal saline group. The difference between silver nitrate and chloroformic garlic extract groups were statistically significant and similar results were noticed between chloroformic garlic extract and normal saline groups. Twenty percent of chloroformic garlic extract had fewer complications such as sclerosing cholangitis, compared to other materials. (author)

  8. Quantum duel revisited

    Science.gov (United States)

    Schmidt, Alexandre G. M.; Paiva, Milena M.

    2012-03-01

    We revisit the quantum two-person duel. In this problem, both Alice and Bob each possess a spin-1/2 particle which models dead and alive states for each player. We review the Abbott and Flitney result—now considering non-zero α1 and α2 in order to decide if it is better for Alice to shoot or not the second time—and we also consider a duel where players do not necessarily start alive. This simple assumption allows us to explore several interesting special cases, namely how a dead player can win the duel shooting just once, or how can Bob revive Alice after one shot, and the better strategy for Alice—being either alive or in a superposition of alive and dead states—fighting a dead opponent.

  9. Seven Issues Revisited

    DEFF Research Database (Denmark)

    Grønbæk, Kaj; Whitehead, Jim; De Bra, Paul;

    2002-01-01

    It has been 15 years since the original presentation by Frank Halasz at Hypertext'87 on seven issues for the next generation of hypertext systems. These issues are: Search and Query Composites Virtual Structures Computation in/over hypertext network Versioning Collaborative Work Extensibility...... and Tailorability Since that time, these issues have formed the nucleus of multiple research agendas within the Hypertext community. Befitting this direction-setting role, the issues have been revisited several times, by Halasz in his 1991 Hypertext keynote talk, and by Randy Trigg in his 1996 Hypertext keynote...... five years later. Additionally, over the intervening 15 years, many research systems have addressed the original seven issues, and new research avenues have opened up. The goal of this panel is to begin the process of developing a new set of seven issues for the next generation of hypertext system...

  10. Deterministic Graphical Games Revisited

    DEFF Research Database (Denmark)

    Andersson, Klas Olof Daniel; Hansen, Kristoffer Arnsfelt; Miltersen, Peter Bro;

    2012-01-01

    , such as retrograde analysis, have been rediscovered independently. We then revisit Washburn’s deterministic graphical games (DGGs), a natural generalization of chess-like games to arbitrary zero-sum payoffs. We study the complexity of solving DGGs and obtain an almost-linear time comparison-based algorithm...... for finding optimal strategies in such games. The existence of a linear time comparison-based algorithm remains an open problem.......Starting from Zermelo’s classical formal treatment of chess, we trace through history the analysis of two-player win/lose/draw games with perfect information and potentially infinite play. Such chess-like games have appeared in many different research communities, and methods for solving them...

  11. Reframing in dentistry: Revisited

    Directory of Open Access Journals (Sweden)

    Sivakumar Nuvvula

    2013-01-01

    Full Text Available The successful practice of dentistry involves a good combination of technical skills and soft skills. Soft skills or communication skills are not taught extensively in dental schools and it can be challenging to learn and at times in treating dental patients. Guiding the child′s behavior in the dental operatory is one of the preliminary steps to be taken by the pediatric dentist and one who can successfully modify the behavior can definitely pave the way for a life time comprehensive oral care. This article is an attempt to revisit a simple behavior guidance technique, reframing and explain the possible psychological perspectives behind it for better use in the clinical practice.

  12. Life quality index revisited

    DEFF Research Database (Denmark)

    Ditlevsen, Ove Dalager

    2004-01-01

    The derivation of the life quality index (LQI) is revisited for a revision. This revision takes into account the unpaid but necessary work time needed to stay alive in clean and healthy conditions to be fit for effective wealth producing work and to enjoyable free time. Dimension analysis...... at birth should not vary between countries. Finally the distributional assumptions are relaxed as compared to the assumptions made in an earlier work by the author. These assumptions concern the calculation of the life expectancy change due to the removal of an accident source. Moreover a simple public...... consistency problems with the standard power function expression of the LQI are pointed out. It is emphasized that the combination coefficient in the convex differential combination between the relative differential of the gross domestic product per capita and the relative differential of the expected life...

  13. Firewall Configuration Errors Revisited

    CERN Document Server

    Wool, Avishai

    2009-01-01

    The first quantitative evaluation of the quality of corporate firewall configurations appeared in 2004, based on Check Point FireWall-1 rule-sets. In general that survey indicated that corporate firewalls were often enforcing poorly written rule-sets, containing many mistakes. The goal of this work is to revisit the first survey. The current study is much larger. Moreover, for the first time, the study includes configurations from two major vendors. The study also introduce a novel "Firewall Complexity" (FC) measure, that applies to both types of firewalls. The findings of the current study indeed validate the 2004 study's main observations: firewalls are (still) poorly configured, and a rule-set's complexity is (still) positively correlated with the number of detected risk items. Thus we can conclude that, for well-configured firewalls, ``small is (still) beautiful''. However, unlike the 2004 study, we see no significant indication that later software versions have fewer errors (for both vendors).

  14. The bar instability revisited

    CERN Document Server

    Chiodi, Filippo; Claudin, Philippe

    2012-01-01

    The river bar instability is revisited, using a hydrodynamical model based on Reynolds averaged Navier-Stokes equations. The results are contrasted with the standard analysis based on shallow water Saint-Venant equations. We first show that the stability of both transverse modes (ripples) and of small wavelength inclined modes (bars) predicted by the Saint-Venant approach are artefacts of this hydrodynamical approximation. When using a more reliable hydrodynamical model, the dispersion relation does not present any maximum of the growth rate when the sediment transport is assumed to be locally saturated. The analysis therefore reveals the fundamental importance of the relaxation of sediment transport towards equilibrium as it it is responsible for the stabilisation of small wavelength modes. This dynamical mechanism is characterised by the saturation number, defined as the ratio of the saturation length to the water depth Lsat/H. This dimensionless number controls the transition from ripples (transverse patte...

  15. Logistics Innovation Process Revisited

    DEFF Research Database (Denmark)

    Gammelgaard, Britta; Su, Shong-Iee Ivan; Yang, Su-Lan

    2011-01-01

    that was triggered by the practical needs of new ways of handling material flows of a hospital. This approach made it possible to revisit theory on logistics innovation process. Findings – Apart from the tangible benefits reported to the case hospital, five findings can be extracted from this study: the logistics...... on internal stakeholders as on external relationships; and logistics innovation process may start out as a dialectic, conflict ridden process and end up in a well-ordered goal-oriented teleological process. Research limitations/implications – In general, the study contributes to the knowledge base...... on an existing model by methodological triangulation in order to learn more about the qualities of actual processes and their implications for theory and practice....

  16. Revisiting the Lambert's Problem

    CERN Document Server

    Izzo, Dario

    2014-01-01

    The orbital boundary value problem, also known as Lambert Problem, is revisited. Building upon Lancaster and Blanchard approach, new relations are revealed and a new variable representing all problem classes, under L-similarity, is used to express the time of flight equation. In the new variable, the time of flight curves have two oblique asymptotes and they mostly appear to be conveniently approximated by piecewise continuous lines. We use and invert such a simple approximation to provide an efficient initial guess to an Householder iterative method that is then able to converge, for the single revoltuion case, in only two iterations. The resulting algorithm is compared to Gooding's procedure revealing to be numerically as accurate, while having a smaller computational complexity.

  17. Klein's double discontinuity revisited

    DEFF Research Database (Denmark)

    Winsløw, Carl; Grønbæk, Niels

    2014-01-01

    Much effort and research has been invested into understanding and bridging the ‘gaps’ which many students experience in terms of contents and expectations as they begin university studies with a heavy component of mathematics, typically in the form of calculus courses. We have several studies...... of bridging measures, success rates and many other aspects of these “entrance transition” problems. In this paper, we consider the inverse transition, experienced by university students as they revisit core parts of high school mathematics (in particular, calculus) after completing the undergraduate...... mathematics courses which are mandatory to become a high school teacher of mathematics. To what extent does the “advanced” experience enable them to approach the high school calculus in a deeper and more autonomous way ? To what extent can “capstone” courses support such an approach ? How could it be hindered...

  18. Comparing the apical microleakage of lateral condensation and chloroform dip techniques with a new obturation method

    Directory of Open Access Journals (Sweden)

    Masoud Saatchi

    2011-01-01

    Full Text Available Background: The final objective of root canal therapy is to create a hermetic seal along the length of the root canal system. For this purpose, many methods and materials have been introduced. The purpose of this study was to compare the apical microleakage in a new obturation technique (true-tug-back with two other obturation techniques (lateral condensation and chloroform dip technique. Methods: In this in vitro study 102 single canal teeth were selected. The crowns were removed, and the canals were prepared using step-back technique. The master apical file was K-file #40. The teeth were divided into 3 experimental groups of 32 teeth. First group were obturated with lateral condensation technique and second group with chloroform dip technique and the third group with true-tug-back technique. Six teeth were used as control group. The teeth were placed in incubator at 100% humidity and 37°c for three days. The roots of the teeth were coated with two layers of nail varnish except for the apical 2 millimeter. Teeth were placed in Methylene blue 2% for one week. The teeth were sectioned vertically and the depth of maximum dye penetration for each tooth was recorded by stereomicroscope. Data were analyzed using ANOVA and Dunkan test. Results: The mean liner dye penetration differences between lateral condensation group (6.88 ± 4.06 mm and chloroform dip technique group (7.16 ± 3.37 mm were not statistically significant (P = 0.719. The differences between true-tug-back group (3.15 ± 0.52 mm and two other groups were statistically significant (P < 0.001. Conclusion: The results of this study showed that the true-tug-back technique can improve apical seal. Further studies are needed for this purpose.

  19. Isolation, fractionation and evaluation of the antiplasmodial properties of Phyllanthus niruri resident in its chloroform fraction

    Institute of Scientific and Technical Information of China (English)

    Obidike Ifeoma; Okhale Samuel; Aboh Mercy Itohan; Salawu Oluwakanyinsola Adeola

    2013-01-01

    Objective:To investigate the antiplasmodial activity ofPhyllanthus niruri(P. niruri) methanol extract(ME) and its fractions in mice.Methods:P. niruri methanol extract and its chloroform, ethanol and aqueous portions were tested against chloroquine-sensitivePlasmodium berghei bergheiin early, established and repository models of infection usingKnight andPeter's4-day suppressive model,Ryley andPeters curative model andPeters prophylactic model respectively. Results:Chemosuppression of parasitaemia(37.65%-50.53%) was elicited by100-400 mg/kg(b.w.) ofME.At doses of100 mg/kg b.w., the chloroform fraction(F1) significantly(P<0.01) suppressed parasitaemia by85.29%, while ethanol and aqueous fractions(F2 andF3, respectively) elicited 67.06% and51.18% chemosuppression.The most active fraction,F1 was selected for further antiplasmodial screening.Inestablished infection,ME reduced parasitaemia(15.81% -62.96%) whileF1 significantly(P<0.01) reduced parasitaemia(44.36%-90.48%), with effects comparable to that of chloroquine(96.48%).The prophylactic antiplasmodial activity ofME(92.50% suppression) was also significant(P<0.01) and was more effective than pyrimethamine(85.00%).Additionally, cell membrane integrity of non-parasitizederythrocytes incubated with125-500 mg/mLF1 was maintained.Conclusions:These findings indicate the antiplasmodial efficacy ofP. niruri methanol extract, and the localization of this effect in its chloroform fraction.

  20. Chloroform and trichloroethylene uptake from water into human skin in vitro: Kinetics and risk implications

    International Nuclear Information System (INIS)

    A model recently proposed by the US Environmental Protection Agency (EPA) predicts that short-term dermal uptakes of organic environmental water contaminants are proportional to the square root of exposure time. The model appears to underestimate dermal uptake, based on very limited in vivo uptake data obtained primarily using human subjects. To further assess this model, we examined in vitro dermal uptake kinetics for aqueous organic chemicals using accelerator mass spectrometry (AMS). Specifically, we examined the kinetics of in vitro dermal uptake of 14C-labeled chloroform and trichloroethylene from dilute (5-ppb) aqueous solutions using full-thickness human cadaver skin exposed for (≤1 hr)

  1. Vasorelaxant effect of diterpenoid lactones from Andrographis paniculata chloroform extract on rat aortic rings

    OpenAIRE

    R.N. Sriramaneni; Omar, Ameer Z.; Salman M Ibrahim; Sadikun Amirin; Asmawi Mohd Zaini

    2010-01-01

    Background: The aim of the present study is to evaluate the possible mechanism of the vasorelaxant effect of the Andrographis paniculata chloroform extract (APCE) and diterpenoids, such as, 14-deoxyandrographolide (DA) and 14-deoxy-11, 12-didehydroandrographolide (DDA), on rat aortic rings. Methods: DA and DDA (10 μM to 40 μM) induce relaxation in the aortic rings pre-contracted with KCl (80 mM). Results: The IC 50 values are 40.47 ± 1.44 and 37.43 ± 1.41%, respectively, and this inhibition i...

  2. Lipase inhibitory activity of chlorophyll a, isofucosterol and saringosterol isolated from chloroform fraction of Sargassum thunbergii.

    Science.gov (United States)

    Kim, Koth-Bong-Woo-Ri; Kim, Min-Ji; Ahn, Dong-Hyun

    2014-01-01

    Three compounds (chlorophyll a, isofucosterol and saringosterol) were isolated from chloroform fraction of Sargassum thunbergii extract. The three compounds had two- to fourfold lower lipase inhibitory activity than that of the CHCl3:MeOH (C:M) (100:1) fraction (fraction I, 83.78% at 1 mg/mL). These results suggested that the high lipase inhibitory activity of fraction I was attributable to the actions of the three compounds. Therefore, S. thunbergii has potential for application as an anti-obesity agent.

  3. Photochemical reactions of poly(3-butoxythiophene-2,5-diyl) with chloroform

    Institute of Scientific and Technical Information of China (English)

    IMIT Mokhtar; YAMAMOTO Takakazu; IMIN Patigul

    2005-01-01

    Photochemical reactions of poly(3-butoxythiophene-2,5-diyl) with chloroform under irradiation with light were studied. The reactions were separately carried out under air, oxygen, and nitrogen. The obtained results showed that this reaction belongs to the pseudo-first-order reaction with a rate constant kobs of 1.4× 10-5 s-1 at room temperature. The presence or absence of air, oxygen, and nitrogen did not have obvious effects on the reaction rate under irradiation with light.

  4. Optimization of the Phenol -Chloroform Silica DNA Extraction Method in Ancient Bones DNA Extraction

    Directory of Open Access Journals (Sweden)

    Morteza Sadeghi

    2014-04-01

    Full Text Available Introduction: DNA extraction from the ancient bones tissues is currently very difficult. Phenol chloroform silica method is one of the methods currently used for this aim. The purpose of this study was to optimize the assessment method. Methods: DNA of 62 bone tissues (average 3-11 years was first extracted with phenol chloroform silica methods and then with changing of some parameters of the methods the extracted DNA was amplified in eight polymorphisms area including FES, F13, D13S317, D16, D5S818, vWA and CD4. Results from samples gained by two methods were compared in acrylamide gel. Results: The average of PCR yield for new method and common method in eight polymorphism regions was 75%, 78%, 81%, 76%, 85%, 71%, 89%, 86% and 64%, 39%, 70%, 49%, 68%, 76%, 71% and 28% respectively. The average of DNA in optimized (in 35l silica density and common method were 267.5 µg/ml with 1.12 purity and 192.76 g/ml with 0.84 purity respectively. Conclusions: According to the findings of this study, it is estimated that longer EDTA attendance is an efficient agent in removing calcium and also adequate density of silica particles can be efficient in removal of PCR inhibitors.

  5. Crystal structure of Boc-(S-ABOC-(S-Ala-(S-ABOC-(S-Phe-OBn chloroform monosolvate

    Directory of Open Access Journals (Sweden)

    Emmanuel Wenger

    2015-10-01

    Full Text Available In the title compound, phenyl (S-2-[(S-(1-{2-[(S-(1-{[(tert-butoxycarbonyl]amino}bicyclo[2.2.2]octan-2-ylformamido]propanamido}bicyclo[2.2.2]octan-2-ylformamido]-3-phenylpropanoate chloroform monosolvate, C42H56N4O7·CHCl3, the α,β-hybrid peptide contains two non-proteinogenic amino acid residues of (S-1-aminobicyclo[2.2.2]octane-2-carboxylic acid [(S-ABOC], two amino acid residues of (S-2-aminopropanoic acid [(S-Ala] and (S-2-amino-3-phenylpropanoic acid [(S-Phe], and protecting groups of tert-butoxycarbonyl (Boc and benzyl ester (OBn. The tetramer folds into a right-handed mixed 11/9 helix stabilized by intramolecular i,i + 3 and i,i − 1 C=O...H—N hydrogen bonds. In the crystal, the oligomers are linked by N—H...O=C hydrogen bonds into chains along the a-axis direction. The chloroform solvent molecules are intercalated between the folded chains via C—H...O=C interactions.

  6. Liquid chloroform structure from computer simulation with a full ab initio intermolecular interaction potential

    International Nuclear Information System (INIS)

    We have calculated the intermolecular interaction energies of the chloroform dimer in 12 orientations using the second-order Møller-Plesset perturbation theory. Single point energies of important geometries were calibrated by the coupled cluster with single and double and perturbative triple excitation method. Dunning's correlation consistent basis sets up to aug-cc-pVQZ have been employed in extrapolating the interaction energies to the complete basis set limit values. With the ab initio potential data we constructed a 5-site force field model for molecular dynamics simulations. We compared the simulation results with recent experiments and obtained quantitative agreements for the detailed atomwise radial distribution functions. Our results were also consistent with previous results using empirical force fields with polarization effects. Moreover, the calculated diffusion coefficients reproduced the experimental data over a wide range of thermodynamic conditions. To the best of our knowledge, this is the first ab initio force field which is capable of competing with existing empirical force fields for liquid chloroform

  7. Phytochemical and Chromatographic Fingerprint Studies on Chloroformic Extracts of Cassia tora L.

    Directory of Open Access Journals (Sweden)

    Patil Sahadeo

    2014-09-01

    Full Text Available Objective: To lay down the chromatographic profile of chloroform extracts of Cassia tora L. by HPTLC technique. Methods: Chloroformic extracts prepared from leaf, flower and seed of Cassia tora L. using Soxhlet apparatus. Qualitative phytochemical screening was done and HPTLC analysis was carried out using CAMAG HPTLC system equipped with automatic TLC sampler IV, TLC scanner 3, REPROSTAR 3 with 12 bit CCD camera for photo documentation, winCATS Planer Chromatography software. Results: The results of qualitative phytochemical analysis confirmed the presence of alkaloids, tannins, flavonoids and terpenoids, but absence of saponins. HPTLC determination of leaf extract showed the presence of 10 components with Rf values ranging from 0.33 - 0.92; seed revealed the presence of 8 components with Rf values in the range of 0.35 – 0.91; flower extract displayed presence of 11 components with Rf values in the range of 0.33 – 0.94. Conclusion: The presence of phytochemicals like flavonoids, terpenoids, tannins and alkaloid in Cassia tora L. increase the probable role in biological activities and their use in medicine. The HPTLC finger printing of Cassia tora L. may be useful in differentiating the species and act as a biochemical marker for this plant.

  8. Revisiting energy efficiency fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Lombard, L.; Velazquez, D. [Grupo de Termotecnia, Escuela Superior de Ingenieros, Universidad de Sevilla, Camino de los Descubrimientos s/n, 41092 Seville (Spain); Ortiz, J. [Building Research Establishment (BRE), Garston, Watford, WD25 9XX (United Kingdom)

    2013-05-15

    Energy efficiency is a central target for energy policy and a keystone to mitigate climate change and to achieve a sustainable development. Although great efforts have been carried out during the last four decades to investigate the issue, focusing into measuring energy efficiency, understanding its trends and impacts on energy consumption and to design effective energy efficiency policies, many energy efficiency-related concepts, some methodological problems for the construction of energy efficiency indicators (EEI) and even some of the energy efficiency potential gains are often ignored or misunderstood, causing no little confusion and controversy not only for laymen but even for specialists. This paper aims to revisit, analyse and discuss some efficiency fundamental topics that could improve understanding and critical judgement of efficiency stakeholders and that could help in avoiding unfounded judgements and misleading statements. Firstly, we address the problem of measuring energy efficiency both in qualitative and quantitative terms. Secondly, main methodological problems standing in the way of the construction of EEI are discussed, and a sequence of actions is proposed to tackle them in an ordered fashion. Finally, two key topics are discussed in detail: the links between energy efficiency and energy savings, and the border between energy efficiency improvement and renewable sources promotion.

  9. Cats protecting birds revisited.

    Science.gov (United States)

    Fan, Meng; Kuang, Yang; Feng, Zhilan

    2005-09-01

    In this paper, we revisit the dynamical interaction among prey (bird), mesopredator (rat), and superpredator (cat) discussed in [Courchamp, F., Langlais, M., Sugihara, G., 1999. Cats protecting birds: modelling the mesopredator release effect. Journal of Animal Ecology 68, 282-292]. First, we develop a prey-mesopredator-superpredator (i.e., bird-rat-cat, briefly, BRC) model, where the predator's functional responses are derived based on the classical Holling's time budget arguments. Our BRC model overcomes several model construction problems in Courchamp et al. (1999), and admits richer, reasonable and realistic dynamics. We explore the possible control strategies to save or restore the bird by controlling or eliminating the rat or the cat when the bird is endangered. We establish the existence of two types of mesopredator release phenomena: severe mesopredator release, where once superpredators are suppressed, a burst of mesopredators follows which leads their shared prey to extinction; and mild mesopredator release, where the mesopredator release could assert more negative impact on the endemic prey but does not lead the endemic prey to extinction. A sharp sufficient criterion is established for the occurrence of severe mesopredator release. We also show that, in a prey-mesopredator-superpredator trophic food web, eradication of introduced superpredators such as feral domestic cats in the BRC model, is not always the best solution to protect endemic insular prey. The presence of a superpredator may have a beneficial effect in such systems. PMID:15998496

  10. Lorentz violation naturalness revisited

    Science.gov (United States)

    Belenchia, Alessio; Gambassi, Andrea; Liberati, Stefano

    2016-06-01

    We revisit here the naturalness problem of Lorentz invariance violations on a simple toy model of a scalar field coupled to a fermion field via a Yukawa interaction. We first review some well-known results concerning the low-energy percolation of Lorentz violation from high energies, presenting some details of the analysis not explicitly discussed in the literature and discussing some previously unnoticed subtleties. We then show how a separation between the scale of validity of the effective field theory and that one of Lorentz invariance violations can hinder this low-energy percolation. While such protection mechanism was previously considered in the literature, we provide here a simple illustration of how it works and of its general features. Finally, we consider a case in which dissipation is present, showing that the dissipative behaviour does not percolate generically to lower mass dimension operators albeit dispersion does. Moreover, we show that a scale separation can protect from unsuppressed low-energy percolation also in this case.

  11. Tracheal relaxant effect of column chromatographic elutes of chloroform fraction of Adhatoda schimperiana leaves in guinea-pigs

    Directory of Open Access Journals (Sweden)

    Zelalem Petros

    2009-01-01

    Full Text Available Adhatoda schimperiana has been used in Ethiopian traditional medicine as a remedy for bronchial asthma. In the present study, tracheal relaxant effect of column chromatographic elutes (CCEs of the chloroform fraction of the leaves of the plant was investigated on guinea-pigs. The intermediate polar CCE of the chloroform fraction showed tracheal relaxant effect as observed by a right-ward shift of the dose-response curve. The maximum response to histamine in presence of the intermediate polar CCE was significantly lower than that of the chloroform fraction (p< 0.05. These results suggest that bioactivity-guided fractionation could show improved tracheal relaxant activity, and the alkaloid-rich fraction of the crude extract might be responsible for the claimed anti-asthmatic effect of the plant.

  12. Benjamin Franklin and Mesmerism, revisited.

    Science.gov (United States)

    McConkey, Kevin M; Perry, Campbell

    2002-10-01

    The authors revisit and update their previous historiographical note (McConkey & Perry, 1985) on Benjamin Franklin's involvement with and investigation of animal magnetism or mesmerism. They incorporate more recent literature and offer additional comment about Franklin's role in and views about mesmerism. Franklin had a higher degree of personal involvement with and a more detailed opinion of mesmerism than has been previously appreciated.

  13. The "Mushroom Cloud" Demonstration Revisited

    Science.gov (United States)

    Panzarasa, Guido; Sparnacci, Katia

    2013-01-01

    A revisitation of the classical "mushroom cloud" demonstration is described. Instead of aniline and benzoyl peroxide, the proposed reaction involves household chemicals such as alpha-pinene (turpentine oil) and trichloroisocyanuric acid ("Trichlor") giving an impressive demonstration of oxidation and combustion reactions that…

  14. Chloroform micro-evaporation induced ordered structures of poly(L-lactide) thin films

    DEFF Research Database (Denmark)

    Huang, Shaoyong; Li, Hongfei; Shang, Yingrui;

    2013-01-01

    and dendritic morphologies with radial periodic variation of thicknesses were formed in dilute solution driven by micro-evaporation of the solvent. Bunched morphologies stacked with a flat-on lozenge-shaped lamellae were created in thinner films. The formation of the concentric ring banded structures......Self-assembly of poly(L-lactide) (PLLA) in thin films induced by chloroform micro-evaporation was investigated by microscopic techniques and X-ray diffraction studies. A film-thickness dependent on highly ordered structures has been derived from disordered films. Ring-banded spherulitic...... was attributed to the periodic rhythmic growth associated with radial periodic changes in the concentration gradient of PLLA. A diffusion-induced rhythmic growth mechanism was proposed to explain the formation of the ring banded morphologies with periodic variation of thicknesses....

  15. Thermal stability of chloroform in the steam condensate cycle of CANDU-PHW nuclear power plant

    International Nuclear Information System (INIS)

    Analysis of samples taken at the Gentilly 2 (Quebec) CANDU-PHW (CANadian Deuterium Uranium - Pressurized Heavy Water) plant after chlorination and demineralization revealed the presence of all four trihalomethanes (THMs) (CHCl3, CHBrCl2, CHBr2Cl and CHBr3) and other unidentified halogenated volatile compounds. Among the THMs, chloroform was the major contaminant. A study of its thermal stability in water at different temperatures confirmed the degradation of the CHCl3 molecule according to the equation CHCl3 + H2O → CO + 3 HCl. The reaction follows first order kinetics and has an activation energy of 100 kJ/mol. The estimated half-life is six seconds at 260 deg C, the maximum temperature of the steam condensate cycle

  16. Ultrafast multiplex CARS investigation of vibrational characteristics in chloroform and PMMA

    International Nuclear Information System (INIS)

    This paper demonstrates the femtosecond time-resolved coherent anti-Stokes Raman scattering by using folded BOXCARS geometry where an ultrashort broadband coherent white light continuum was used as Stokes pulse, and carries out the non-contact detection at long distance. The CARS signal is so easy to be detected that it can be seen even by nude eye. The C–H bonds of chloroform or PMMA were detected and the vibration modes belonging to the side chain and the main chain in PMMA were also compared. Their vibrational characteristics involved decay process and quantum beating were discussed. This modified CARS experimental technique could make up the deficiency of traditional CARS technique. (atomic and molecular physics)

  17. Chloroform Aided Extraction Spectrophotometric Determination of Rhenium Using Thiocyanate Complexing Agent

    Institute of Scientific and Technical Information of China (English)

    E. Keshavarz Alamdari; S.K. Sadrnezhaad; Z. Mos-hefi Shabestari

    2005-01-01

    A new technique is developed for quantitative determination of rhenium in aqueous media containing molybdenum,iron and copper ions. The method seems easier and more accurate than the traditional ones. It consists of the formation of rhenium thiocyanate complex, which is extracted with chloroform at the presence of hydrochloric acid.This complex is a highly visible light absorbent that can easily be detected with the aid of a spectrophotometer. The maximum absorbance (λmax) observed for this complex was in the visible range of 430~435 nm. The experimental results showed that in a concentration range from 0.5~8 mg/L, the absorbance behavior of the rhenium thiocyanate complex is followed to the Beer-Lambert law.

  18. A modified Phenol-chloroform extraction method for isolating circulating cell free DNA of tumor patients

    Directory of Open Access Journals (Sweden)

    Clemens Hufnagl

    2013-03-01

    Full Text Available Searching for new cancer biomarkers, circulating cell-free DNA (cfDNA has become an appealing target of interest as an elevated level of cfDNA has been detected in the circulation of cancer patients in comparison with healthy controls. Since cfDNA can be isolated from the circulation and other body fluids of patients without harming their physical condition, cfDNA is becoming a promising candidate as a novel non-invasive biomarker for cancer. The challenge in the diagnostic analysis of cfDNA is its very low presence in human plasma/serum and its partially strong fragmentation. Here we evaluated a modified phenol/chloroform extraction method for the isolation of cfDNA and compared it with published standard methods for cfDNA isolation.

  19. Characterization of Methylocystis strain JTA1 isolated from aged refuse and its tolerance to chloroform

    Institute of Scientific and Technical Information of China (English)

    Tiantao Zhao; Lijie Zhang; Yunru Zhang; Zhilin Xing; Xuya Peng

    2013-01-01

    To accelerate the efficiency of methane biodegradation in landfills,a Gram-negative,rod-shaped,non-motile,non-spore-forming bacterium,JTA1,which can utilize methane as well as acetate,was isolated from the Laogang MSW landfills,Shanghai,China.Strain JTA1 was a member of genus Methylocystis on the basis of 16S rRNA and pmoA gene sequence similarity.The maximum specific cell growth rates (μmax=0.042 hr-1,R2=0.995) was derived through Boltzmann simulation,and the apparent half-saturation constants (Km(app) =7.08 mmol/L,R2 =0.982) was calculated according to Michaelis-Menton hyperbolic model,indicating that Methylocystis strain JTA1 had higher-affinity potential for methane oxidation than other reported methanotrophs.By way of adding the strain JTA1 culture,the methane consumption of aged refuse reached 115 mL,almost two times of control experiment.In addition,high tolerance of Methylocystis strain JTA1 to chloroform could facilitate the methane oxidation of aged refuse bio-covers.At the chloroform concentration of 50 mg/L,the methane-oxidation rate of bio-cover reached 0.114 mL/(day.g),much higher than the highest rate,0.0135 mL/(day.g),of reported bio-covers.In conclusion,strain JTA1 opens up a new possibility for environmental biotechnology,such as soil or landfills bioremediation and wastewater decontamination.

  20. Identification of sitosteryl glucoside palmitate in a chloroform-derived fraction of Phyllanthus niruri with antiplasmodial and peripheral antinociceptive properties

    Institute of Scientific and Technical Information of China (English)

    Ezenyi Ifeoma Chinwude; Kulkarni Roshan; Joshi Swati; Salawu Oluwakanyinsola Adeola; Emeje Martins

    2014-01-01

    Objective: To evaluate the antiplasmodial properties of fractions of chloroform portion of Phyllanthus niruri (P. niruri) methanol extract and identify a suitable chemical marker present therein. Methods: Chloroform portion of P. niruri methanol extract was separated from silica gel using gradient systems of hexane, ethylacetate and methanol. The fractions were screened for antiplasmodial activity against Plasmodium falciparum HB3 and FcM29. Fractions with IC50 Results:Fractions 12-14 were very active (IC50 Conclusions:Our findings illustrate antiplasmodial column fractions of P. niruri with analgesic activity and identify sitosteryl glucoside palmitate as a chemical marker of activity.

  1. Treatment of natural ovine malignant theileriosis with a chloroform extract of the plant Peganum harmala : research communication

    Directory of Open Access Journals (Sweden)

    M. Mirzaiedehaghi

    2006-09-01

    Full Text Available One hundred sheep naturally infected with Theileria lestoquardi were treated with a chloroform extract of the plant Peganum harmala. The treatment was continued for 5 days, the dose of extract being 5 mg/kg per day. Sixty-five of the sheep responded to treatment and recovered but 35 did not and died. The cure rate was 65 %

  2. Factors associated with sources, transport, and fate of chloroform and three other trihalomethanes in untreated groundwater used for drinking water

    Science.gov (United States)

    Carter, Janet M.; Moran, Michael J.; Zogorski, John S.; Price, Curtis V.

    2012-01-01

    Multiple lines of evidence for indicating factors associated with the sources, transport, and fate of chloroform and three other trihalomethanes (THMs) in untreated groundwater were revealed by evaluating low-level analytical results and logistic regression results for THMs. Samples of untreated groundwater from wells used for drinking water were collected from 1996-2007 from 2492 wells across the United States and analyzed for chloroform, bromodichloromethane, dibromochloromethane, and bromoform by a low-level analytical method implemented in April 1996. Using an assessment level of 0.02 μg/L, chloroform was detected in 36.5% of public-well samples and 17.6% of domestic-well samples, with most concentrations less than 1 μg/L. Brominated THMs occurred less frequently than chloroform but more frequently in public-well samples than domestic-well samples. For both public and domestic wells, THMs occurred most frequently in urban areas. Logistic regression analyses showed that the occurrence of THMs was related to nonpoint sources such as urban land use and to point sources like septic systems. The frequent occurrence and concentration distribution pattern of THMs, as well as their frequent co-occurrence with other organic compounds and nitrate, all known to have anthropogenic sources, and the positive associations between THM occurrence and dissolved oxygen and recharge indicate the recycling of water that contains THMs and other anthropogenic contaminants.

  3. Chemical changes in the chloroform-paraffin-dye system irradiated with 60Co gamma-rays, 2

    International Nuclear Information System (INIS)

    Studies have been carried out on the amount of hydrogen chloride formed by the radiolysis of chloroform in a solid paraffin-chloroform-Methyl Yellow system, and the color changes from yellow to red and absorption energy observed. The amount of hydrogen chloride formed and the intensity of the red color were determined with a pH meter, a spectrophotometer, and a color/ color-difference meter. It was found that the color-difference meter had the most excellent spectral response and sensitivity for measurement of the irradiated sample, and that the color-difference, ΔE, obtained by reflectometry increased proportionally with the increase in the radiation dose throughout a region of 100 -- 5000 R. When a solid sample composed of 1.0 kg paraffin (m.p. 62 -- 640C), 0.74 kg chloroform and 3.4 x 10-3 mol Methyl Yellow was subjected to 1000 R irradiation at 200C, 2.5 x 1014 molecules of hydrogen chloride were formed in 1.0 g of the solid sample with the absorption energy of 5.9 x 1016 eV, 3.2 x 1016 eV of which contributed to chloroform as the absorption energy. (author)

  4. Acute Toxicity Investigation and Anti-diarrhoeal Effect of the Chloroform-Methanol Extract of the Leaves of Persea americana.

    Science.gov (United States)

    Christian E, Odo; Okwesili Fc, Nwodo; Parker E, Joshua; Okechukwu Pc, Ugwu

    2014-01-01

    Persea americana is a plant used by traditional medicine practitioners to treat ailments including diarrhoea and diabetes mellitus in Nigeria. Hence, the chloroform and the methanol fractions of the chloroform-methanol extract of the leaves of P. americana were evaluated for their acute toxicity as well as anti-diarrhoeal effects in Wistar rats to substantiate this claim. The chloroform and methanol fractions [at graded doses of 100 and 200 mg/Kg body weight (b.w) of each] were studied for their anti-diarrhoeal effects in terms of the reductions in the wetness of faeces and the frequency of defaecation of castor oil-induced diarrhoea. To understand the mechanism of their anti-diarrhoeal effects, their actions were further evaluated on castor oil-induced enteropooling (intestinal fluid accumulation). The median lethal dose (LD50) of the methanol fraction was found to be less than 5000 mg/Kg b.w. At the two doses, the chloroform and the methanol fractions showed dose-dependent significant (p americana possesses significant anti-diarrhoeal effect and may be a potent source of anti-diarrhoeal drug(s) in future. PMID:25237361

  5. Atmospheric predictability revisited

    Directory of Open Access Journals (Sweden)

    Lizzie S. R. Froude

    2013-06-01

    Full Text Available This article examines the potential to improve numerical weather prediction (NWP by estimating upper and lower bounds on predictability by re-visiting the original study of Lorenz (1982 but applied to the most recent version of the European Centre for Medium Range Weather Forecasts (ECMWF forecast system, for both the deterministic and ensemble prediction systems (EPS. These bounds are contrasted with an older version of the same NWP system to see how they have changed with improvements to the NWP system. The computations were performed for the earlier seasons of DJF 1985/1986 and JJA 1986 and the later seasons of DJF 2010/2011 and JJA 2011 using the 500-hPa geopotential height field. Results indicate that for this field, we may be approaching the limit of deterministic forecasting so that further improvements might only be obtained by improving the initial state. The results also show that predictability calculations with earlier versions of the model may overestimate potential forecast skill, which may be due to insufficient internal variability in the model and because recent versions of the model are more realistic in representing the true atmospheric evolution. The same methodology is applied to the EPS to calculate upper and lower bounds of predictability of the ensemble mean forecast in order to explore how ensemble forecasting could extend the limits of the deterministic forecast. The results show that there is a large potential to improve the ensemble predictions, but for the increased predictability of the ensemble mean, there will be a trade-off in information as the forecasts will become increasingly smoothed with time. From around the 10-d forecast time, the ensemble mean begins to converge towards climatology. Until this point, the ensemble mean is able to predict the main features of the large-scale flow accurately and with high consistency from one forecast cycle to the next. By the 15-d forecast time, the ensemble mean has lost

  6. Enceladus' tidal dissipation revisited

    Science.gov (United States)

    Tobie, Gabriel; Behounkova, Marie; Choblet, Gael; Cadek, Ondrej; Soucek, Ondrej

    2016-10-01

    A series of chemical and physical evidence indicates that the intense activity at Enceladus' South Pole is related to a subsurface salty water reservoir underneath the tectonically active ice shell. The detection of a significant libration implies that this water reservoir is global and that the average ice shell thickness is about 20-25km (Thomas et al. 2016). The interpretation of gravity and topography data further predicts large variations in ice shell thickness, resulting in a shell potentially thinner than 5 km in the South Polar Terrain (SPT) (Cadek et al. 2016). Such an ice shell structure requires a very strong heat source in the interior, with a focusing mechanism at the SPT. Thermal diffusion through the ice shell implies that at least 25-30 GW is lost into space by passive diffusion, implying a very efficient dissipation mechanism in Enceladus' interior to maintain such an ocean/ice configuration thermally stable.In order to determine in which conditions such a large dissipation power may be generated, we model the tidal response of Enceladus including variable ice shell thickness. For the rock core, we consider a wide range of rheological parameters representative of water-saturated porous rock materials. We demonstrate that the thinning toward the South Pole leads to a strong increase in heat production in the ice shell, with a optimal thickness obtained between 1.5 and 3 km, depending on the assumed ice viscosity. Our results imply that the heat production in the ice shell within the SPT may be sufficient to counterbalance the heat loss by diffusion and to power eruption activity. However, outside the SPT, a strong dissipation in the porous core is required to counterbalance the diffusive heat loss. We show that about 20 GW can be generated in the core, for an effective viscosity of 1012 Pa.s, which is comparable to the effective viscosity estimated in water-saturated glacial tills on Earth. We will discuss the implications of this revisited tidal

  7. The natural chlorine cycle - Formation of the carcinogenic and greenhouse gas compound chloroform in drinking water reservoirs.

    Science.gov (United States)

    Forczek, Sándor T; Pavlík, Milan; Holík, Josef; Rederer, Luděk; Ferenčík, Martin

    2016-08-01

    Chlorine cycle in natural ecosystems involves formation of low and high molecular weight organic compounds of living organisms, soil organic matter and atmospherically deposited chloride. Chloroform (CHCl3) and adsorbable organohalogens (AOX) are part of the chlorine cycle. We attempted to characterize the dynamical changes in the levels of total organic carbon (TOC), AOX, chlorine and CHCl3 in a drinking water reservoir and in its tributaries, mainly at its spring, and attempt to relate the presence of AOX and CHCl3 with meteorological, chemical or biological factors. Water temperature and pH influence the formation and accumulation of CHCl3 and affect the conditions for biological processes, which are demonstrated by the correlation between CHCl3 and ΣAOX/Cl(-) ratio, and also by CHCl3/ΣAOX, CHCl3/AOXLMW, CHCl3/ΣTOC, CHCl3/TOCLMW and CHCl3/Cl(-) ratios in different microecosystems (e.g. old spruce forest, stagnant acidic water, humid and warm conditions with high biological activity). These processes start with the biotransformation of AOX from TOC, continue via degradation of AOX to smaller molecules and further chlorination, and finish with the formation of small chlorinated molecules, and their subsequent volatilization and mineralization. The determined concentrations of chloroform result from a dynamic equilibrium between its formation and degradation in the water; in the Hamry water reservoir, this results in a total amount of 0.1-0.7 kg chloroform and 5.2-15.4 t chloride. The formation of chloroform is affected by Cl(-) concentration, by concentrations and ratios of biogenic substrates (TOC and AOX), and by the ratios of the substrates and the product (feedback control by chloroform itself). PMID:27231877

  8. THE FAILURE OF CHLOROFORM ADMINISTERED IN THE DRINKING WATER TO INDUCE RENAL TUBULAR CELL NEOPLASIA IN MALE F344/N RATS

    Science.gov (United States)

    The failure of chloroform administered in drinking water to induce renal tubular cell neoplasia in male F344/N rats Chloroform (TCM) has been demonstrated to be a renal carcinogen in the male Osborne-Mendel rat when administered either by corn oil gavage or in drin...

  9. Revisiting SU(N) integrals

    CERN Document Server

    Zuber, Jean-Bernard

    2016-01-01

    In this note, I revisit integrals over $\\SU(N)$ of the form $ \\int DU\\, U_{i_1j_1}\\cdots U_{i_pj_p}\\Ud_{k_1l_1}\\cdots \\Ud_{k_nl_n}$. While the case $p=n$ is well known, it seems that explicit expressions for $p=n+N$ had not appeared in the literature. Similarities and differences, in particular in the large $N$ limit, between the two cases are discussed

  10. The Damped String Problem Revisited

    CERN Document Server

    Gesztesy, Fritz

    2010-01-01

    We revisit the damped string equation on a compact interval with a variety of boundary conditions and derive an infinite sequence of trace formulas associated with it, employing methods familiar from supersymmetric quantum mechanics. We also derive completeness and Riesz basis results (with parentheses) for the associated root functions under less smoothness assumptions on the coefficients than usual, using operator theoretic methods (rather than detailed eigenvalue and root function asymptotics) only.

  11. Markowitz Revisited: Social Portfolio Engineering

    OpenAIRE

    Gasser, Stephan; Kremser, Thomas; Rammerstorfer, Margarethe; Weinmayer, Karl

    2014-01-01

    In recent years socially responsible investing has become an increasingly more popular subject with both private and institutional investors. At the same time, a number of scientific papers have been published on socially responsible investments (SRIs), covering a broad range of topics, from what actually defines SRIs to the financial performance of SRI funds in contrast to non-SRI funds. In this paper, we revisit Markowitz' Portfolio Selection Theory and propose a modification...

  12. Leadership and Management Theories Revisited

    OpenAIRE

    Madsen, Mona Toft

    2001-01-01

    The goal of the paper is to revisit and analyze key contributions to the understanding of leadership and management. As a part of the discussion a role perspective that allows for additional and/or integrated leader dimensions, including a change-centered, will be outlined. Seemingly, a major challenge on the substantive level is the integration of soft and hard managerial functions, while the concepts used in presenting these should at least in transition be able to contain a distinction bet...

  13. Bis{2-methoxy-6-[(E-(4-methylbenzyliminomethyl]phenolato}palladium(II chloroform monosolvate

    Directory of Open Access Journals (Sweden)

    Hadariah Bahron

    2014-08-01

    Full Text Available In the title complex, [Pd(C16H16NO22]·CHCl3, the PdII cation lies on an inversion center. One Cl atom of the CHCl3 solvent molecule lies on a twofold axis and the C—H group is disordered with equal occupancies about this axis with the other Cl atom in a general position with full occupancy. The PdII cation is four-coordinate and adopts a square-planar geometry via coordination of the imine N and phenolic O atoms of the two bidentate Schiff base anions. The N and O atoms of these ligands are mutually trans. The plane of the benzene ring makes a dihedral angle of 73.52 (10° with that of the methoxyphenolate ring. In the crystal, molecules of the PdII complex are arranged into sheets parallel to the ac plane, and the chloroform solvent molecules are located in the interstitial areas between the complex molecules. Weak intermolecular C—H...O and C—H...π interactions stabilize the packing.

  14. Gastroprotective activity of the chloroform extract of the roots from Arctium lappa L.

    Science.gov (United States)

    Dos Santos, Ana C; Baggio, Cristiane H; Freitas, Cristina S; Lepieszynski, Juliana; Mayer, Bárbara; Twardowschy, André; Missau, Fabiana C; dos Santos, Elide P; Pizzolatti, Moacir G; Marques, Maria C A

    2008-06-01

    Arctium lappa L. is used in folk medicine as a diuretic, depurative and digestive stimulant and in dermatological conditions. The objective of this study was to evaluate the effect and the possible mechanisms involved in the gastroprotective effects of a chloroform extract (CE) of the roots from A. lappa and its fractions. Oral pretreatment with CE (10, 30 and 100 mg kg(-1)) significantly reduced gastric lesions induced by ethanol by 61%, 70% and 76%, respectively. Oral administration of CE (100 mg kg(-1) per day for 7 days) reduced the chronic gastric ulceration induced by acetic acid by 52%. Intraduodenal CE (100, 300 and 600 mg kg(-1)) reduced the total acidity of gastric secretion by 22%, 22% and 33%, respectively, while i.p. administration (10, 30 and 100 mg kg(-1)) inhibited total acidity by 50%, 60% and 67%, respectively. In-vitro, CE inhibited H+, K+ -ATPase activity with an EC50 of 53 microgmL(-1) and fraction A (30 and 100 microgmL(-1)) reduced this by 48% and 89%, respectively. CE had no effect on gastrointestinal motility. CE (250 microgmL(-1)) and fraction B (100 and 250 microgmL(-1)) had free-radical scavenging ability, inhibiting 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical activity by 50%, 20% and 55%, respectively. Collectively, the results show that the CE protects animals from gastric lesions by reducing gastric acid secretion via inhibition of gastric H+, K+ -ATPase.

  15. Toxicity of chloroform extract of prunus africana stem bark in rats: gross and histological lesions.

    Science.gov (United States)

    Gathumbi, P K; Mwangi, J W; Mugera, G M; Njiro, S M

    2002-05-01

    Chloroform extract of Prunus africana (Hook f. (Rosaceae) did not cause clinical signs or pathology in rats at daily oral doses of up to 1,000 mg/kg for 8 weeks. The extract caused marked clinical signs, organ damage and a 50% mortality rate at a dose of 3.3 g/kg for 6 days. The main lesions observed at this dose were marked centrilobular hepatocellular degeneration and necrosis, diffuse nephrosis, myocardial degeneration, lymphocytic necrosis and neuronal degeneration. The morphological damage in these tissues caused a corresponding rise in blood biochemical parameters namely, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, creatine kinase and blood urea nitrogen. The target organs of toxicity of this extract are the liver, kidney and heart. Overt toxicity occurred only after the administration of multiple doses of 3.3 g/kg body weight. These findings confirm the suitability of this extract for therapeutic use, since the doses used in the therapy of prostate gland are much lower than those used in this study and would therefore not be expected to cause pathological changes.

  16. Wirelike charge transport dynamics for DNA-lipid complexes in chloroform.

    Science.gov (United States)

    Mishra, Ashutosh Kumar; Young, Ryan M; Wasielewski, Michael R; Lewis, Frederick D

    2014-11-01

    The dynamics of charge separation and charge recombination have been determined for lipid complexes of DNA capped hairpins possessing stilbene electron-acceptor and -donor chromophores separated by base-pair domains that vary in length and base sequence in chloroform solution by means of femtosecond time-resolved transient absorption spectroscopy. The results obtained for the DNA-lipid complexes are compared with those previously obtained in our laboratories for the same hairpins in aqueous buffer. The charge separation and charge recombination times for the lipid complexes are consistently much shorter than those determined in aqueous solution and are only weakly dependent on the number of base pairs separating the acceptor and donor. The enhanced rate constants for forward and return charge transport in DNA-lipid complexes support proposals that solvent gating is responsible, to a significant extent, for the relatively low rates of charge transport for DNA in water. Moreover, they suggest that DNA-lipid complexes may prove useful in the development of DNA-based molecular electronic devices. PMID:25299823

  17. 不同醇类对磷钨酸催化超临界醇解液化木屑的影响%Effect of solvent on the solvolysis liquefaction of sawdust with phosphotungstic acid under supercritical condition

    Institute of Scientific and Technical Information of China (English)

    曾常伟; 吕建华; 郑怀玉; 陈学榕; 黄彪

    2016-01-01

    Phosphotungstic acid is an efficient, green and highly acidic hte erogeneousc atalyst.Different from to her solid heteropholy acids, phosphotungstic acid si dissoluble in alcohols.This research makes ht e best use of the physicochemical properties of phosphotungstic acid combining with high solubility ofs upercritical alcohols. Sawdust was liquefied in the supercritical solvent using phosphotungstic acid as catalyst.The fe fects of different solvents on t he solvolysis l iquefaction and the compositions of b io-oil were investigated. Each solvolysis experiment was conductde at 260℃for 30 min ni a stainless-steel autoclave, in which 1 g of fir sawdust, 0.5 g of phosphotungsic acid, 150 g of alcohol ( such as methanol, ethanol, n-propanol ori so-propano l) were added. The liquefaction products were separated by filtration after quenching the reaction.Then, the filtrate was etx racted with n-hexane and separated into light bio-oil adn heavy bio-oil atf er removni g the solvent. Simultaneously, the residue, heavy bio-oil and light bio-oil were characterized by Fourier transform infrared (FT-IR) and Agilent 7890A/5975C gas chromatography-mass spectrometry (GC-MS).The results show that the reaction pressure and polarity of alcoholic solvents significantly i mpact the liquefaction efficiency and liquefaction products.The liquefaction yield using methanol, ethanol, n-propaon l and iso-propanol is 54.75%, 90.29%,85.90%and 89.15%, respectively, while the relative content of mani compound esters in liquefaction products is 43.759%, 23.531%, 41.761% and 28.619%, respectively.Especially, the relative content of methyl levulinate in methanol system is 33 .374%. The main compounds in liquefaction products using methanol, ethanol, iso-propanol as solvent are esters and phenols, while n-propanol system are esters, ketones and alcohols.M eanw hile, levulinate erster, which is produced through the reaction of cellulose/hemicellulose and alcohols, is detected in the liquefaction

  18. Estimates of European emissions of methyl chloroform using a Bayesian inversion method

    Directory of Open Access Journals (Sweden)

    M. Maione

    2014-03-01

    Full Text Available Methyl chloroform (MCF is a man-made chlorinated solvent contributing to the destruction of stratospheric ozone and is controlled under the Montreal Protocol on Substances that Deplete the Ozone Layer. Long-term, high-frequency observations of MCF carried out at three European sites show a constant decline of the background mixing ratios of MCF. However, we observe persistent non-negligible mixing ratio enhancements of MCF in pollution episodes suggesting unexpectedly high ongoing emissions in Europe. In order to identify the source regions and to give an estimate of the magnitude of such emissions, we have used a Bayesian inversion method and a point source analysis, based on high-frequency long-term observations at the three European sites. The inversion identified south-eastern France (SEF as a region with enhanced MCF emissions. This estimate was confirmed by the point source analysis. We performed this analysis using an eleven-year data set, from January 2002 to December 2012. Overall emissions estimated for the European study domain decreased nearly exponentially from 1.1 Gg yr−1 in 2002 to 0.32 Gg yr−1 in 2012, of which the estimated emissions from the SEF region accounted for 0.49 Gg yr−1 in 2002 and 0.20 Gg yr−1 in 2012. The European estimates are a significant fraction of the total semi-hemisphere (30–90° N emissions, contributing a minimum of 9.8% in 2004 and a maximum of 33.7% in 2011, of which on average 50% are from the SEF region. On the global scale, the SEF region is thus responsible from a minimum of 2.6% (in 2003 to a maximum of 10.3% (in 2009 of the global MCF emissions.

  19. Vasorelaxant effect of diterpenoid lactones from Andrographis paniculata chloroform extract on rat aortic rings

    Directory of Open Access Journals (Sweden)

    R N Sriramaneni

    2010-01-01

    Full Text Available Background: The aim of the present study is to evaluate the possible mechanism of the vasorelaxant effect of the Andrographis paniculata chloroform extract (APCE and diterpenoids, such as, 14-deoxyandrographolide (DA and 14-deoxy-11, 12-didehydroandrographolide (DDA, on rat aortic rings. Methods: DA and DDA (10 μM to 40 μM induce relaxation in the aortic rings pre-contracted with KCl (80 mM. Results: The IC 50 values are 40.47 ± 1.44 and 37.43 ± 1.41%, respectively, and this inhibition is antagonized by increasing the Ca 2+ concentration in the Kreb′s medium. The results indicate that APCE, DA, and DDA may have a calcium anatgonist property. APCE, DA, and DDA also relax norepinephrene (NE-induced sustained contractions with IC 50 values 41.63 ± 1.19, 49.22 ± 2.76, and 37.46 ± 1.41% and this relaxant effect is unaffected by the removal of the endothelium or by the presence of indomethacin and Nω-nitro-L-arginine (L-NAME. Moreover, DA and DDA inhibit the phasic and tonic contractions induced by NE in a concentration-dependent manner and show the most potent inhibition on phasic contraction (P < 0.01. Conclusion: This study shows that APCE, DA, and DDA pre-treatment presents a more potent inhibition compared to post-treatment, after the tension has reached a steady state. These results suggest that the vasorelaxation of APCE, DA, and DDA direct the inhibition of the calcium influx. The vasorelaxant effect is more active in the calcium independent pathway and more sensitive in the intial stage of contraction.

  20. Dynamic real-time monitoring of chloroform in an indoor swimming pool air using open-path Fourier transform infrared spectroscopy.

    Science.gov (United States)

    Chen, M-J; Duh, J-M; Shie, R-H; Weng, J-H; Hsu, H-T

    2016-06-01

    This study used open-path Fourier transform infrared (OP-FTIR) spectroscopy to continuously assess the variation in chloroform concentrations in the air of an indoor swimming pool. Variables affecting the concentrations of chloroform in air were also monitored. The results showed that chloroform concentrations in air varied significantly during the time of operation of the swimming pool and that there were two peaks in chloroform concentration during the time of operation of the pool. The highest concentration was at 17:30, which is coincident with the time with the highest number of swimmers in the pool in a day. The swimmer load was one of the most important factors influencing the chloroform concentration in the air. When the number of swimmers surpassed 40, the concentrations of chloroform were on average 4.4 times higher than the concentration measured without swimmers in the pool. According to the results of this study, we suggest that those who swim regularly should avoid times with highest number of swimmers, in order to decrease the risk of exposure to high concentrations of chloroform. It is also recommended that an automatic mechanical ventilation system is installed to increase the ventilation rate during times of high swimmer load.

  1. The BUME method: a novel automated chloroform-free 96-well total lipid extraction method for blood plasma[S

    OpenAIRE

    Löfgren, Lars; Ståhlman, Marcus; Forsberg, Gun-Britt; Saarinen, Sinikka; Nilsson, Ralf; Göran I Hansson

    2012-01-01

    Lipid extraction from biological samples is a critical and often tedious preanalytical step in lipid research. Primarily on the basis of automation criteria, we have developed the BUME method, a novel chloroform-free total lipid extraction method for blood plasma compatible with standard 96-well robots. In only 60 min, 96 samples can be automatically extracted with lipid profiles of commonly analyzed lipid classes almost identically and with absolute recoveries similar or better to what is ob...

  2. Complexation of two non-fully hydrogen bonded aromatic hydrazide heptamers toward n-octyl-α-L-glucopyranoside in chloroform

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Two aromatic hydrazide haptamers have been prepared,with both consisting of two hydrogen bonded folded segments. Compared to their fully hydrogen bonded analogues,the flexibility of their backbones increases due to lack of one or two intramolecular hydrogen bonds at the middle aromatic unit. (2D) 1H NMR,circular dichroism and fluorescent studies revealed that both oligomers moderately complex n-octyl-α-L-glucopyranoside in chloroform.

  3. Complexation of two non-fully hydrogen bonded aromatic hydrazide heptamers toward n-octyl-α-L-glucopyranoside in chloroform

    Institute of Scientific and Technical Information of China (English)

    DU Ping; XU YunXiang; JIANG XiKui; LI ZhanTing

    2009-01-01

    Two aromatic hydrazide haptamers have been prepared, with both consisting of two hydrogen bonded folded segments. Compared to their fully hydrogen bonded analogues, the flexibility of their backbones increases due to lack of one or two intramolecular hydrogen bonds at the middle aromatic unit. (2D) 1H NMR, circular dichroism and fluorescent studies revealed that both oligomers moderately complex n-octyl-α-L-glucopyranoside in chloroform.

  4. The Utilization of Chloroform Post-Treatment to Improve the Adhesion of Au Thin Films onto PMMA

    Science.gov (United States)

    Krist, Kathleen; Hughes, Chris; Hu, Xiaofeng; Augustine, Brian

    2015-03-01

    The metallization of Au onto plastics is an important processing step in the fabrication of microfluidic devices. While its corrosion resistance and excellent electrical and thermal conductivity make Au a good choice, its inertness results in poor adhesion to polymer surfaces. Previous studies have indicated that exposing commercially available Poly(methyl methacrylate) (PMMA) sheets to chloroform vapor following Au deposition significantly improves adhesion. In this study, we deposited 6 nm of Au onto 1.50 mm thick PMMA and exposed the samples to vapor released from chloroform heated on a hot plate set at 70 °C. The force required to remove the Au thin films was determined by placing samples on a polisher spinning at 150 rpm and utilizing UV-VIS spectroscopy to measure the transmittance of 700 nm light through the films to quantify their removal as a function of applied polishing force. The Au thin films were also characterized using AFM. AFM images demonstrated a progressive roughening of the surface corresponding to an increase in applied force. Additionally, these images support a model in which the chloroform treatment softens the PMMA surface, producing a softened layer that the polisher removes simultaneously with the Au thin film. Undergraduate.

  5. Survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro.

    Science.gov (United States)

    Golami, Shirzad; Rahimi-Esboei, Bahman; Mousavi, Parisa; Marhaba, Zahra; Youssefi, Mohammad Reza; Rahimi, Mohammad Taghi

    2016-03-01

    Giardiasis is a parasitic cosmopolitan disease that the rate of infection in developing countries is considerable. This infection directly is associated with poor hygienic conditions, poor water quality control, and overcrowding. Reinfection and drug resistance are two major problems in endemic areas. Recently, researchers are concentrating on herbal drugs as a proper solution. Therefore, the objective of the present study was to survey on efficacy of chloroformic extract of Artemisia annua against Giardia lamblia trophozoite and cyst in vitro. G. lamblia cysts were prepared from faces of giardiasis patients from different hospitals of Mazandaran Medical University. Four concentrations (1, 10, 50 and 100 mg/ml) of chloroformic extract of A. annua were utilized for 1, 5, 30, 60 and 180 min. Viability of G. lamblia cysts was confirmed by 0.1 % Eosin staining. Cyst and trophozoite contact (intermix) of G. lamblia with extract of A. annua with variant concentrations (1, 10, 50 and 100 mg/ml) after 1 and 180 min caused following cyst and trophozoite elimination rates: (67, 69, 71 and 73 %), (65, 67, 67 and 72 %), (94, 96, 97 and 99 %) and (100, 100, 100 and 100 %), respectively. Authors from the current investigation draw a conclusion that chloroformic extract of A. annua has the ability to eliminate G. lamblia cysts and trophozoites in vitro. PMID:27065604

  6. Oxidation of trichloroethylene, 1,1-dichloroethylene, and chloroform by toluene/o-xylene monooxygenase from Pseudomonas stutzeri OX1.

    Science.gov (United States)

    Chauhan, S; Barbieri, P; Wood, T K

    1998-08-01

    Toluene/o-xylene monooxygenase (ToMO) from Pseudomonas stutzeri OX1, which oxidizes toluene and o-xylene, was examined for its ability to degrade the environmental pollutants trichloroethylene (TCE), 1, 1-dichloroethylene (1,1-DCE), cis-1,2-DCE, trans-1,2-DCE, chloroform, dichloromethane, phenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 2,3,5,6-tetrachlorophenol, and 2,3,4,5, 6-pentachlorophenol. Escherichia coli JM109 that expressed ToMO from genes on plasmid pBZ1260 under control of the lac promoter degraded TCE (3.3 microM), 1,1-DCE (1.25 microM), and chloroform (6.3 microM) at initial rates of 3.1, 3.6, and 1.6 nmol/(min x mg of protein), respectively. Stoichiometric amounts of chloride release were seen, indicating mineralization (2.6, 1.5, and 2.3 Cl- atoms per molecule of TCE, 1,1-DCE, and chloroform, respectively). Thus, the substrate range of ToMO is extended to include aliphatic chlorinated compounds. PMID:9687467

  7. Anti-diabetic potential of chloroform extract of flowers of Calotropis gigantea: An in vitro and in vivo study

    Directory of Open Access Journals (Sweden)

    N K Choudhary

    2011-01-01

    Full Text Available The chloroform extract of Calotropis gigantea flowers was evaluated for anti-diabetic activity in alloxan-induced hyperglycemia in vivo and inhibition of α-amylase and α-glucosidase in vitro. It was also intended to establish correlation between the serum marker antioxidant enzymes and diabetes. Diabetes was induced by a single intraperitoneal injection of alloxan monohydrate freshly prepared in a dose of 150 mg/kg. Chloroform extract showing presence of flavonoids was administered orally at the doses of 100 and 200 mg/kg for 21 consecutive days. Fasting blood glucose level, glycosylated haemoglobin, blood glutathione, serum creatinine kinase, serum lactate dehydrogenase levels as well as final change in body weight were evaluated. In vitro inhibition of carbohydrate digestive enzymes (α-amylase and α-glucosidase was also determined. Experimental findings showed moderately significant anti-diabetic potential of extract in terms of reduction of fasting glucose level in diabetic rats. The extract was found statistically significant in maintaining the level of serum marker antioxidant enzymes. Overall, the effect of chloroform extract particularly 200 mg/kg was moderate as compared to that of standard drug glibenclamide.

  8. The power reinforcement framework revisited

    DEFF Research Database (Denmark)

    Nielsen, Jeppe; Andersen, Kim Normann; Danziger, James N.

    2016-01-01

    public organizations. This article revisits the 30-yearold power reinforcement framework by means of an empirical analysis on the use of mobile technology in a large-scale programme in Danish public sector home care. It explores whether and to what extent administrative management has controlled decision......-dominated and centrally controlled technologies that were the main focus of the 1970s and 1980s studies. Yet this study concludes that there is general support for the reinforcement framework in the contemporary application of mobile technology in public sector home care....

  9. Leadership and Management Theories Revisited

    DEFF Research Database (Denmark)

    Madsen, Mona Toft

    2001-01-01

    The goal of the paper is to revisit and analyze key contributions to the understanding of leadership and management. As a part of the discussion a role perspective that allows for additional and/or integrated leader dimensions, including a change-centered, will be outlined. Seemingly, a major...... challenge on the substantive level is the integration of soft and hard managerial functions, while the concepts used in presenting these should at least in transition be able to contain a distinction between hard, soft, and general practices....

  10. Jesus and the law revisited

    Directory of Open Access Journals (Sweden)

    William R.G. Loader

    2011-06-01

    Full Text Available This article revisited the issue of Jesus’ attitude towards the Torah on the basis of a critical discussion of the most recent extensive treatment of the theme by Meier in his A marginal Jew: Rethinking the historical Jesus: Volume four: Law and love (2009. It engaged Meier’s contribution in the light of contemporary research, concluding that, whilst Meier provided an erudite analysis, his thesis that Jesus’ teaching on divorce and oaths revoked Mosaic law did not convince, for it did not adequately consider the extent to which the contemporary interpretation of the Torah could encompass such radicalisation.

  11. Des aliments tu feras medecine: Hippocrate revisite

    OpenAIRE

    Lahlou, Saadi

    1999-01-01

    "Let foods be your medicine Hippocrates revisited". In this article the author discusses the behaviour of consumers, concepts of 'health foods' and helth eating towards food and the rise of businesses built around the health food industry.

  12. Ethanopharmacological study of the aqueous, chloroform, ethanol leaves extracts and latex of Calotropisprocera in diabetic rats

    Directory of Open Access Journals (Sweden)

    Ali Ismaiel Ali-Abd Alrheam

    2015-11-01

    Full Text Available Introduction: Calotropisprocera is a member of the plant family Asclepiadaceae, a shrub about 6m high and is widely distributed in the kingdom of Saudi Arabia. This study aimed to show some medicinal potentials and biological activity of Calotropisprocera and to discover new natural, safe and effective materials available in the Saudi Arabia environment. Marerial and Methods:The leaves extracts and latex of Calotropisprocerawere investigated for its anti-hyperglycemic effect in Male Wister Albino rats. Diabetes was induced by administration of single dose of streptozotocin (STZ, 50 mg/kg, I.P. Forty two male albino rats, weighting 150-200 gm divided into seven groups, each consisted of 6 rats as follows: Group I : Normal control, Group II: Diabetic control, Group III: Diabetic rats given Glibenclamide 600 and #956;g/kg, Group IV: Diabetic rats given aqueous leaves extracts C. procera200mg/kg b. wt, Group V: Diabetic rats given chloroform leaves extracts C. procera200mg/kg b. wt, Group VI: Diabetic rats given ethanol leaves extracts C. procera200mg/kg b. wt, Group VII: Diabetic rats given latex of C. procera200mg/kg b. wt.The leaves extracts and latex of Calotropisprocera were administered as single dose per day to diabetes-induced rats for a period of 15 days.The effect of C. proceraon blood glucose level was measured in the diabetic rats. Serum lipid profile (Total cholesterol, triglycerides, low density, and high density lipoprotein also were measured. The activities were also compared to that effect produced by a standard anti-diabetic agent, glibenclamide 500 and #956;g/kg. Results and Discussion:The results showed a significant decrease in the mean level of blood glucose and serum cholesterol, Triglycrides, HDL, LDL. Calotropisprocera appears to be a rich source of phytoconstituents that activate and inhence a pharmacological response of different parts of the body and this study need further studies to shows the complete properties of the

  13. Genomic DNA extraction from whole blood stored from 15- to 30-years at -20 °C by rapid phenol-chloroform protocol: a useful tool for genetic epidemiology studies.

    Science.gov (United States)

    Di Pietro, Fabio; Ortenzi, Francesco; Tilio, Martina; Concetti, Fabio; Napolioni, Valerio

    2011-02-01

    Long-term stored (LTS) whole blood collection can be an important source of DNA without collection costs, but there is a lack of information on methods useful to extract genomic DNA from such type of biological material. Here we report a simple and fast revisited phenol/chloroform extraction method from LTS whole blood. Protocol reliability was assessed by comparison with proteinase K and silica-gel membrane spin column-based DNA extraction methods using LTS -20 °C whole blood from 1980, and by testing it on 82 whole blood samples, collected from 1980 to 1995, with high quality (A(260/280) = 1.79 ± 0.32 O.D., A(260/230) = 1.45 ± 0.52 O.D.) and quantity results. Genotyping efficiency was also checked by performing RFLP-PCR and ASP-PCR of p53 Pro72Arg (rs1042522) SNP and hTERT MNS16A VNTR, respectively, resulting in 100% of samples successfully typed. In addition to the goodness and the efficiency of method proposed here, this protocol achieves working time reduction combining extraction and purification steps, allowing to work at room temperature. Furthermore, phenol is able to inactivate any potential nuclease and potential infective sources from the first step on. Based on these results we also conclude that LTS -20 °C whole blood samples may be considered a reliable and potential resource for future genotyping studies and retrospective analysis in a genetic epidemiological setting.

  14. Gelation behaviour of a bent-core dihydrazide derivative: effect of incubation temperature in chloroform and toluene.

    Science.gov (United States)

    Zhang, Chunxue; Zhang, Tianren; Ji, Nan; Zhang, Yan; Bai, Binglian; Wang, Haitao; Li, Min

    2016-02-01

    In this work, a new kind of gelator, 1,3-bis[(3,4-dioctyloxy phenyl) hydrazide]phenylene (BP8-C), containing two dihydrazide units as the rigid bent-core, has been synthesized and investigated. It was demonstrated that BP8-C is an efficient gelator which can gel various organic solvents, such as ethanol, benzene, toluene, chloroform, etc. Both an opaque gel (O-gel) and a transparent gel (T-gel), which is more stable, were obtained with BP8-C in chloroform at different incubation temperatures. Kinetic data based on fluorescence spectra revealed that the T-gels showed a larger Avrami parameter (n = 1.44 at 20 °C) than that of the O-gels (n = 1.21 for gelation at temperatures below 0 °C). While BP8-C did form the opaque gel in toluene, gelation took longer at lower incubation temperatures and even precipitated out below 0 °C. The kinetic Avrami analysis on sols of BP8-C with different concentrations shows a two-phrase mechanism, i.e. the n values are between 0.88 and 1.74 followed by 1.69 and 3.01 throughout the temperature range of 5 °C and 35 °C for 5.34 mg mL(-1) BP8-C in toluene, indicating that the fibers formed first and then bundled to produce compact networks. We propose that supersaturation governs the formation of gel in chloroform and that the diffusion process denominates gelation in toluene. XRD and FT-IR measurements confirmed that the xerogels prepared at different temperatures in different solvents exhibited a Col(h) structure and that there are three molecules in one columnar slice. Our results indicate that the gelation process, morphology of the gels and thus the final properties of the gels depend strongly on the preparation conditions such as temperature, solvent, concentration, etc.

  15. The alkaline comet assay used in evaluation of genotoxic damage of drinking water disinfection by-products (bromoform and chloroform

    Directory of Open Access Journals (Sweden)

    Messaouda Khallef

    2015-06-01

    Full Text Available The alkaline comet assay (pH 12.3 is a useful method for monitoring genotoxic effects of environmental pollutants in the root nuclei of Allium cepa and various plants; it allows the detection of single- and double-strand breaks, incomplete excision-repair sites and cross-links. It has been introduced to detect even small changes in DNA structure. It is a technically simple, highly sensitive, fast and economic test which detects in vitro and in vivo genotoxicity (DNA integrity and packing mode in any cell types examined, and requires just a few cells for its execution (Liman et al., 2011; Yıldız et al., 2009. Chloroform and bromoform are the most important trihalomethanes found in drinking water. Different concentrations of bromoform (25, 50, 75and 100µg/ml and chloroform (25, 50, 100 and 200 µg/ml were introduced to onion tuber roots. Distilled water was used as a negative control and methyl methansulfonate (MMS-10 µg/ml as positive control. All obtained data were subjected to statistical analyses by using SPSS 15.0 for Windows software. For comparison purposes, Duncan multiple range tests using one-way analysis of variance (ANOVA were employed and p<0.05 was accepted as the test of significance. Comet assay results showed that DNA damage was significant at p <0.05 for the different concentrations of chloroform and bromoform compared to the negative control which has a damage rate equal to 3.5 ± 0.7 and the positive control which has damage rate equal to 13.5 ± 2.12. The exposure of root tip cells to these disinfection by-products increases DNA damage. All concentrations examined in this study of bromoform and chloroform cause significant harm, which could be due to DNA damage induced by oxidative stress. The measurement of DNA damage in the nuclei of higher plant tissues is a new area of study with SCGE. This assay could be incorporated into in situ monitoring of atmosphere, water and soil: the comet assay allows a fast detection without

  16. Effects of organophosphorus donors in the extraction of Uranium(VI) with N-acetyl benzamide in chloroform

    International Nuclear Information System (INIS)

    The liquid-liquid extraction of Uranium(VI) from aqueous nitrate solution by a mixture of N-acetyl benzamide and Organophosphorus donors in chloroform is reported. Concentration of the metal was measured by fluorescence technique and synergism was observed in the extraction of Uranium(VI). Stoichiometries of extracted species in both individual and mixed extraction were ascertained by slope ratio analysis. From the extraction data, overall equilibrium constants for binary and ternary extractions were calculated. Thermodynamic parameters controlling the nature of extraction were also evaluated. (author)

  17. Fusion curves and thermodynamic properties of carbon tetrachloride, chloroform, bromoform and silicon tetrachloride at pressure up to 3500 Mpa

    Institute of Scientific and Technical Information of China (English)

    Zhu Rong-Jiao; Xu Wei; Tian Yi-Ling; Hao Ji-Shuang

    2008-01-01

    The fusion temperature as a function of pressure for carbon tetrachloride, chloroform, bromoform and silicon tetrachloride at pressures up to 3500MPa has been determined. The experimental data were fitted by the equation Tfus = T0(1 + Ap/a1)a2 exp(-a3△p) and the changes of the molar enthalpy and molar internal energy on fusion were calculated using the parameters of the fitted equation. Comparisons with the data from the literature show that the experimental data, parameters of fitted equations, changes of the molar enthalpy and molar internal energy are reliable.

  18. The role of renal proximal tubule P450 enzymes in chloroform-induced nephrotoxicity: Utility of renal specific P450 reductase knockout mouse models

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Senyan [Kidney Institute and Division of Nephrology, Changzheng Hospital, Shanghai 200003 (China); Wadsworth Center, New York State Department of Health, and School of Public Health, State University of New York, Albany, NY 12201 (United States); Yao, Yunyi; Lu, Shijun; Aldous, Kenneth; Ding, Xinxin [Wadsworth Center, New York State Department of Health, and School of Public Health, State University of New York, Albany, NY 12201 (United States); Mei, Changlin, E-mail: chlmei1954@126.com [Kidney Institute and Division of Nephrology, Changzheng Hospital, Shanghai 200003 (China); Gu, Jun, E-mail: jungu@wadsworth.org [Wadsworth Center, New York State Department of Health, and School of Public Health, State University of New York, Albany, NY 12201 (United States)

    2013-10-01

    The kidney is a primary target for numerous toxic compounds. Cytochrome P450 enzymes (P450) are responsible for the metabolic activation of various chemical compounds, and in the kidney are predominantly expressed in proximal tubules. The aim of this study was to test the hypothesis that renal proximal tubular P450s are critical for nephrotoxicity caused by chemicals such as chloroform. We developed two new mouse models, one having proximal tubule-specific deletion of the cytochrome P450 reductase (Cpr) gene (the enzyme required for all microsomal P450 activities), designated proximal tubule-Cpr-null (PTCN), and the other having proximal tubule-specific rescue of CPR activity with the global suppression of CPR activity in all extra-proximal tubular tissues, designated extra-proximal tubule-Cpr-low (XPT-CL). The PTCN, XPT-CL, Cpr-low (CL), and wild-type (WT) mice were treated with a single oral dose of chloroform at 200 mg/kg. Blood, liver and kidney samples were obtained at 24 h after the treatment. Renal toxicity was assessed by measuring BUN and creatinine levels, and by pathological examination. The blood and tissue levels of chloroform were determined. The severity of toxicity was less in PTCN and CL mice, compared with that of WT and XPT-CL mice. There were no significant differences in chloroform levels in the blood, liver, or kidney, between PTCN and WT mice, or between XPT-CL and CL mice. These findings indicate that local P450-dependent activities play an important role in the nephrotoxicity induced by chloroform. Our results also demonstrate the usefulness of these novel mouse models for studies of chemical-induced kidney toxicity. - Highlights: • New mouse models were developed with varying P450 activities in the proximal tubule. • These mouse models were treated with chloroform, a nephrotoxicant. • Studies showed the importance of local P450s in chloroform-induced nephrotoxicity.

  19. The use of alkaline hydrolysis as a novel strategy for chloroform remediation: the feasibility of using construction wastes and evaluation of carbon isotopic fractionation.

    Science.gov (United States)

    Torrentó, Clara; Audí-Miró, Carme; Bordeleau, Geneviève; Marchesi, Massimo; Rosell, Mònica; Otero, Neus; Soler, Albert

    2014-01-01

    Laboratory and field-scale pilot experiments were performed to evaluate the feasibility of chloroform degradation by alkaline hydrolysis and the potential of δ(13)C values to assess this induced reaction process at contaminated sites. In batch experiments, alkaline conditions were induced by adding crushed concrete (pH 12.33 ± 0.07), a filtered concrete solution (pH 12.27 ± 0.04), a filtered cement solution (pH 12.66 ± 0.02) and a pH 12 buffer solution (pH 11.92 ± 0.11). The resulting chloroform degradation after 28 days was 94, 96, 99, and 72%, respectively. The experimental data were described using a pseudo-first-order kinetic model, resulting in pseudo-first-order rate constant values of 0.10, 0.12, 0.20, and 0.05 d(-1), respectively. Furthermore, the significant chloroform carbon isotopic fractionation associated with alkaline hydrolysis of chloroform (-53 ± 3‰) and its independence from pH in the admittedly limited tested pH range imply a great potential for the use of δ(13)C values for in situ monitoring of the efficacy of remediation approaches based on alkaline hydrolysis. The carbon isotopic fractionation obtained at the lab scale allowed the calculation of the percentage of chloroform degradation in field-scale pilot experiments where alkaline conditions were induced in two recharge water interception trenches filled with concrete-based construction wastes. A maximum of approximately 30-40% of chloroform degradation was achieved during the two studied recharge periods. Although further research is required, the treatment of chloroform in groundwater through the use of concrete-based construction wastes is proposed. This strategy would also imply the recycling of construction and demolition wastes for use in value-added applications to increase economic and environmental benefits. PMID:24410407

  20. The use of alkaline hydrolysis as a novel strategy for chloroform remediation: the feasibility of using construction wastes and evaluation of carbon isotopic fractionation.

    Science.gov (United States)

    Torrentó, Clara; Audí-Miró, Carme; Bordeleau, Geneviève; Marchesi, Massimo; Rosell, Mònica; Otero, Neus; Soler, Albert

    2014-01-01

    Laboratory and field-scale pilot experiments were performed to evaluate the feasibility of chloroform degradation by alkaline hydrolysis and the potential of δ(13)C values to assess this induced reaction process at contaminated sites. In batch experiments, alkaline conditions were induced by adding crushed concrete (pH 12.33 ± 0.07), a filtered concrete solution (pH 12.27 ± 0.04), a filtered cement solution (pH 12.66 ± 0.02) and a pH 12 buffer solution (pH 11.92 ± 0.11). The resulting chloroform degradation after 28 days was 94, 96, 99, and 72%, respectively. The experimental data were described using a pseudo-first-order kinetic model, resulting in pseudo-first-order rate constant values of 0.10, 0.12, 0.20, and 0.05 d(-1), respectively. Furthermore, the significant chloroform carbon isotopic fractionation associated with alkaline hydrolysis of chloroform (-53 ± 3‰) and its independence from pH in the admittedly limited tested pH range imply a great potential for the use of δ(13)C values for in situ monitoring of the efficacy of remediation approaches based on alkaline hydrolysis. The carbon isotopic fractionation obtained at the lab scale allowed the calculation of the percentage of chloroform degradation in field-scale pilot experiments where alkaline conditions were induced in two recharge water interception trenches filled with concrete-based construction wastes. A maximum of approximately 30-40% of chloroform degradation was achieved during the two studied recharge periods. Although further research is required, the treatment of chloroform in groundwater through the use of concrete-based construction wastes is proposed. This strategy would also imply the recycling of construction and demolition wastes for use in value-added applications to increase economic and environmental benefits.

  1. Anti-inflammatory effects of the chloroform extract of Pulicaria guestii ameliorated the neutrophil infiltration and nitric oxide generation in rats.

    Science.gov (United States)

    Alghaithy, A A; El-Beshbishy, H A; Abdel-Naim, A B; Nagy, A A; Abdel-Sattar, E M

    2011-11-01

    Pulicaria guestii Rech.f. & Rawi is a fragrant, perennial herb, which grows wild, west of Al-Madinah, Saudi Arabia. Several reports were published on the anti-inflammatory activity of the sesquiterpene lactones, phenolics and flavonoids, which constitute the main active constituents of the members of the genus Pulicaria. The present study was designed to explore the potential anti-inflammatory effect of P. guestii in several experimental models. The methanol extract of the dried aerial parts of P. guestii was extracted with petroleum ether, chloroform and n-butanol. The chloroform extract was analysed on TLC and examined under UV and visible light in presence of AlCl(3) spray. The free radical scavenging activity and the total phenolic content in the CHCl(3) extract were estimated. The crude methanol extract and the CHCl(3) fraction were examined against carrageenin-induced paw edema and ear edema induced by croton oil application. The crude methanolic extract significantly reduced carrageenin-induced rat paw edema. After fractionation, the chloroform fraction caused significant reduction in carrageenin-induced rat paw edema in addition to diminishing prostaglandin E(2) (PGE(2)) in the inflammatory exudates. Topical application of chloroform fraction significantly reduced rat ear edema induced by croton oil application. In the same model, chloroform fraction reduced neutrophil infiltration, as indicated by the significant decrease in myeloperoxidase activity, and ameliorated histopathological changes induced by croton oil application. In lipopolysaccharide-induced inflammation in rat air pouch, chloroform fraction significantly reduced the nitric oxide level and tumor necrosis factor-α release. In conclusion, the chloroform fraction of P. guestii extract possesses anti-inflammatory activity in several experimental models. Further investigations are needed to identify the active constituents responsible for this anti-inflammatory activity.

  2. The role of renal proximal tubule P450 enzymes in chloroform-induced nephrotoxicity: Utility of renal specific P450 reductase knockout mouse models

    International Nuclear Information System (INIS)

    The kidney is a primary target for numerous toxic compounds. Cytochrome P450 enzymes (P450) are responsible for the metabolic activation of various chemical compounds, and in the kidney are predominantly expressed in proximal tubules. The aim of this study was to test the hypothesis that renal proximal tubular P450s are critical for nephrotoxicity caused by chemicals such as chloroform. We developed two new mouse models, one having proximal tubule-specific deletion of the cytochrome P450 reductase (Cpr) gene (the enzyme required for all microsomal P450 activities), designated proximal tubule-Cpr-null (PTCN), and the other having proximal tubule-specific rescue of CPR activity with the global suppression of CPR activity in all extra-proximal tubular tissues, designated extra-proximal tubule-Cpr-low (XPT-CL). The PTCN, XPT-CL, Cpr-low (CL), and wild-type (WT) mice were treated with a single oral dose of chloroform at 200 mg/kg. Blood, liver and kidney samples were obtained at 24 h after the treatment. Renal toxicity was assessed by measuring BUN and creatinine levels, and by pathological examination. The blood and tissue levels of chloroform were determined. The severity of toxicity was less in PTCN and CL mice, compared with that of WT and XPT-CL mice. There were no significant differences in chloroform levels in the blood, liver, or kidney, between PTCN and WT mice, or between XPT-CL and CL mice. These findings indicate that local P450-dependent activities play an important role in the nephrotoxicity induced by chloroform. Our results also demonstrate the usefulness of these novel mouse models for studies of chemical-induced kidney toxicity. - Highlights: • New mouse models were developed with varying P450 activities in the proximal tubule. • These mouse models were treated with chloroform, a nephrotoxicant. • Studies showed the importance of local P450s in chloroform-induced nephrotoxicity

  3. Identification of sitosteryl glucoside palmitate in a chloroform-derived fraction of Phyllanthus niruri with antiplasmodial and peripheral antinociceptive properties

    Institute of Scientific and Technical Information of China (English)

    Ezenyi; Ifeoma; Chinwude; Kulkarni; Roshan; Joshi; Swati; Salawu; Oluwakanyinsola; Adeola; Emeje; Martins

    2014-01-01

    Objective:To evaluate the antiplasmodial properties of fractions of chloroform portion of Phyllanthus niruri(P.niruri) methanol extract and identify a suitable chemical marker present therein.Methods:Chloroform portion of P.niruri methanol extract was separated from silica gel using gradient systems of hexane,ethylacetate and methanol.The fractions were screened for antiplasmodial activity against Plasmodium falciparum HB3 and FcM29.Fractions with IC50<10μg/ml.against parasites were further screened for peripheral analgesic activity,while cytotoxicity was evaluated using THP-1 cells.Results:Fractions 12-14 were very active(IC50<10 μg/mL) against Plasmodium falciparum and showed no significant cytotoxicity.Fractions 12 and 13 exhibited significant(P<0.01) reduction in acetic acid-induced writhing in mice,decreasing the number of writhes by 66.67% and 65.22% respectively and comparable with 100 mg/kg aspirin(65.22%).From fraction 12,a compound was isolated and identified as sitosteryl-6-β-D-glucoside-6’-palmitate by 1H,13C nuclear magnetic resonance and mass spectroscopies.Conclusions:Our findings illustrate antiplasmodial column fractions of P.niruri with analgesic activity and identify sitosteryl glucoside pahmitate as a chemical marker of activity.

  4. Crystal structure of Boc-(S)-ABOC-(S)-Ala-(S)-ABOC-(S)-Phe-OBn chloro-form monosolvate.

    Science.gov (United States)

    Wenger, Emmanuel; Moulat, Laure; Legrand, Baptiste; Amblard, Muriel; Calmès, Monique; Didierjean, Claude

    2015-10-01

    In the title compound, phenyl (S)-2-[(S)-(1-{2-[(S)-(1-{[(tert-but-oxy)carbon-yl]amino}-bicyclo-[2.2.2]octan-2-yl)formamido]-propanamido}-bicyclo-[2.2.2]octan-2-yl)formamido]-3-phenyl-propano-ate chloro-form monosolvate, C42H56N4O7·CHCl3, the α,β-hybrid peptide contains two non-proteinogenic amino acid residues of (S)-1-amino-bicyclo-[2.2.2]octane-2-carb-oxy-lic acid [(S)-ABOC], two amino acid residues of (S)-2-amino-propanoic acid [(S)-Ala] and (S)-2-amino-3-phenyl-propanoic acid [(S)-Phe], and protecting groups of tert-but-oxy-carbonyl (Boc) and benzyl ester (OBn). The tetra-mer folds into a right-handed mixed 11/9 helix stabilized by intra-molecular i,i + 3 and i,i - 1 C=O⋯H-N hydrogen bonds. In the crystal, the oligomers are linked by N-H⋯O=C hydrogen bonds into chains along the a-axis direction. The chloro-form solvent mol-ecules are inter-calated between the folded chains via C-H⋯O=C inter-actions. PMID:26594404

  5. Optical constants and dispersion equations of lecithin, cholesterol, fucose, and chloroform: measurements in vacuum-ultraviolet to visible wavelength regions

    International Nuclear Information System (INIS)

    The optical constants, n and k, of solutions of lecithin, cholesterol, and fucose and of the solvent chloroform were measured for the spectral region 1348 to 6407 A by a reflectance method. Absorption peaks were found in chloroform at about 1393 and 1631 A and were attributed, respectively, to sigma → sigma/sup */ electron transitions at the C--H and C--Cl bonds and an n → sigma/sup */ electron transition at the C--Cl bond. A procedure for the determination of the optical constants of a solute from those of the solution and solvent is developed and applied. The procedure is also applied to calculate the optical constants of a solution from those of the components. From the values of the optical constants, dispersion equation parameters and van der Waals parameters were calculated for the compounds. The static electronic polarizabilities of the substances studies were found to depend little (less than 6%) on the concentration of solution used in the measurement. Values of polarizabilities obtained agreed closely with those obtained by the addition of bond polarizabilities

  6. Synthesis, growth, structural, thermal, optical properties of new metal-organic crystals: Methyltriphenylphosphonium iodide thiourea and methyltriphenylphosphonium iodide chloroform hemisolvate

    Science.gov (United States)

    Shivachev, Boris L.; Kossev, Krassimir; Dimowa, Louiza T.; Yankov, Georgi; Petrov, Todor; Nikolova, Rositsa P.; Petrova, Nadia

    2013-08-01

    Crystals of methyltriphenylphosphonium iodide thiourea (1) and methyltriphenylphosphonium iodide chloroform hemisolvate (2) were obtained for the first time. Fourier transform infrared (FTIR) spectral studies have been performed to identify the functional groups. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study their thermal properties. The optical transmittance window and the lower cutoff wavelength have been identified by UV-vis studies. Crystals of the title compounds suitable for single crystal X-ray analyses were successfully grown by slow evaporation and diffraction data were collected to elucidate the molecular structure and interactions. The proton donors (phosphonium) and proton acceptor (iodine) in the structure of 1 provide infrastructure to introduce charge asymmetry while in 2 chloroform molecule is not involved in the charge transfer. An optical quality crystal of 1 (5×4×2 mm3) was obtained by macroseeding. The crystal has developed facets with major ones (001) and (00¯1). A crystal of 1 was tested with 1060 nm laser radiation and showed second harmonic generation (SHG).

  7. Induction of apoptosis in HeLa cells by chloroform fraction of seed extracts of Nigella sativa

    Directory of Open Access Journals (Sweden)

    Alshatwi Ali A

    2009-11-01

    Full Text Available Abstract Background Cancer remains one of the most dreaded diseases causing an astonishingly high death rate, second only to cardiac arrest. The fact that conventional and newly emerging treatment procedures like chemotherapy, catalytic therapy, photodynamic therapy and radiotherapy have not succeeded in reverting the outcome of the disease to any drastic extent, has made researchers investigate alternative treatment options. The extensive repertoire of traditional medicinal knowledge systems from various parts of the world are being re-investigated for their healing properties. This study progresses in the direction of identifying component(s from Nigella sativa with anti cancer acitivity. In the present study we investigated the efficacy of Organic extracts of Nigella sativa seed powder for its clonogenic inhibition and induction of apoptosis in HeLa cancer cell. Results Methanolic, n-Hexane and chloroform extracts of Nigella sativa seedz effectively killed HeLa cells. The IC50 values of methanolic, n-hexane, and chloroform extracts of Nigella sativa were 2.28 μg/ml, 2.20 μg/ml and 0.41 ng/ml, respectively. All three extracts induced apoptosis in HeLa cells. Apoptosis was confirmed by DNA fragmentation, western blot and terminal transferase-mediated dUTP-digoxigenin-end labeling (TUNEL assay. Conclusion Western Blot and TUNEL results suggested that Nigella sativa seed extracts regulated the expression of pro- and anti- apoptotic genes, indicating its possible development as a potential therapeutic agent for cervical cancer upon further investigation.

  8. Revisiting tourist behavior via destination brand worldness

    Directory of Open Access Journals (Sweden)

    Murat Kayak

    2016-11-01

    Full Text Available Taking tourists’ perspective rather than destination offerings as its core concept, this study introduces “perceived destination brand worldness” as a variable. Perceived destination brand worldness is defined as the positive perception that a tourist has of a country that is visited by tourists from all over the world. Then, the relationship between perceived destination brand worldness and intention to revisit is analyzed using partial least squares regression. This empirical study selects Taiwanese tourists as its sample, and the results show that perceived destination brand worldness is a direct predictor of intention to revisit. In light of these empirical findings and observations, practical and theoretical implications are discussed.

  9. Anti-diabetic activity of the chloroform extract of Senecio mikanioides Otto in streptozotocin induced diabetic rats

    Directory of Open Access Journals (Sweden)

    Hanan S. M. Marzouk

    2011-08-01

    Full Text Available Objective: In this study, we examined the effect of oral administration of the chloroform extract of Senecio mikanioides Otto for a period of 30 days at doses of 100, 300 or 500 mg/kg body weight/day on streptozotocin induced diabetic rats. Methods: Male Sprague-Dawley rats were divided into five groups and classified into; extract treatment group received 100, 300 or 500 mg/kg body weight per day by oral gavage for 30 days; diabetic group administered intraperitoneally a single dose (75 mg/kg body weight of streptozotocin (STZ; diabetic rats plus tolbutamide group where diabetic rats received the standard hypoglycemic drug tolbutamide (100 mg/kg body weight per day by oral gavage for 30 days; diabetic rats plus extract group where diabetic rats received the extract (same doses by gavage for 30 days; as well as a normal group for comparison. In all of these groups, the levels of glucose and insulin were checked in blood, while the levels of reduced glutathione (GSH, nitric oxide (NO, lipid peroxidation (TBARS and thioredoxin reductase (TrxR activity were measured in pancreatic tissues. Results: The results revealed that STZ administration resulted in significant elevation in the level of both TBARS and NO with depletion in the level of GSH as compared with control accompanied with hyperglycemia, hypo-insulinemia and low insulin sensitivity. Moreover, the activity of pancreatic TrxR was lower than the control group. Feeding the diabetic rats for 30 days with the extract normalizes the previous biochemical parameters in dose dependent manner reaching near the tolbutamide treated group at the highest dose. Conclusion: The chloroform extract of Senecio mikanioides Otto exhibited antidiabetic activity and it corrected the insulin level and its sensitivity in experimentally induced diabetic rats in dose dependent manner. The current results clearly indicated the beneficial effects of the chloroform extract of Senecio mikanioides Otto in both

  10. Gelation behaviour of a bent-core dihydrazide derivative: effect of incubation temperature in chloroform and toluene.

    Science.gov (United States)

    Zhang, Chunxue; Zhang, Tianren; Ji, Nan; Zhang, Yan; Bai, Binglian; Wang, Haitao; Li, Min

    2016-02-01

    In this work, a new kind of gelator, 1,3-bis[(3,4-dioctyloxy phenyl) hydrazide]phenylene (BP8-C), containing two dihydrazide units as the rigid bent-core, has been synthesized and investigated. It was demonstrated that BP8-C is an efficient gelator which can gel various organic solvents, such as ethanol, benzene, toluene, chloroform, etc. Both an opaque gel (O-gel) and a transparent gel (T-gel), which is more stable, were obtained with BP8-C in chloroform at different incubation temperatures. Kinetic data based on fluorescence spectra revealed that the T-gels showed a larger Avrami parameter (n = 1.44 at 20 °C) than that of the O-gels (n = 1.21 for gelation at temperatures below 0 °C). While BP8-C did form the opaque gel in toluene, gelation took longer at lower incubation temperatures and even precipitated out below 0 °C. The kinetic Avrami analysis on sols of BP8-C with different concentrations shows a two-phrase mechanism, i.e. the n values are between 0.88 and 1.74 followed by 1.69 and 3.01 throughout the temperature range of 5 °C and 35 °C for 5.34 mg mL(-1) BP8-C in toluene, indicating that the fibers formed first and then bundled to produce compact networks. We propose that supersaturation governs the formation of gel in chloroform and that the diffusion process denominates gelation in toluene. XRD and FT-IR measurements confirmed that the xerogels prepared at different temperatures in different solvents exhibited a Col(h) structure and that there are three molecules in one columnar slice. Our results indicate that the gelation process, morphology of the gels and thus the final properties of the gels depend strongly on the preparation conditions such as temperature, solvent, concentration, etc. PMID:26659559

  11. 氯油制备氯仿新工艺%New preparation process of chloroform from chlorinated oil

    Institute of Scientific and Technical Information of China (English)

    乐晓兵

    2001-01-01

    In this paper, a new chloroform production process by reaction of chlorinated oil with dimethyl amine instead of lime is introduced, in which N, N- dimethyl methanamide is coproduct. The characteristics of this process lie in that the raw materials are easy to get and have low prices,its unique extraction technology avoid using drying agent and other assistants, the use ratio of carbon contained in trichlroacetic aldehyde reaches to 100% and there aren't formate substances to be discharged. The quality of pilot product produced by the new process is better than that of the product produced by lime process,the quality of chloroform reach to the high-class required by National Standard GB 4118-92,DMF products reach to the requirement of HG 2028-91. Moreover, with the adoption of the newprocess, the production cost of chloroform was reduced by1 387.87 RMB¥/t compared with that oflime process, and the problem of environment pollution was thoroughly solved,achieving the aims of production cost reduction and environmental protection.%介绍了一种采用二甲胺代替石灰与氯油反应,在生产氯仿的同时联产N,N-二甲基甲酰胺的新工艺。该工艺的特点在于原料易得且价格低廉,具有独创性的萃取技术避免了使用干燥剂及其它助剂,理论上使三氯乙醛中碳的利用率达到100%,无甲酸盐类物质排放。新工艺中试产品的质量优于石灰法产品质量,氯仿质量达到国标GB4118-92优等品要求,DMF产品达到HG2028-91标准要求。而且采用新工艺后,公司氯仿成本比石灰法下降1 387.87元/t,环境污染问题也得到根本性解决,达到降低成本、保护环境的双重目的。

  12. Electrochemical dechlorination of chloroform in neutral aqueous solution on palladium/foam-nickel and palladium/polymeric pyrrole film/foam-nickel electrodes

    Institute of Scientific and Technical Information of China (English)

    SUN Zhirong; LI Baohua; HU Xiang; SHI Min; HOU Qingnan; PENG Yongzhen

    2008-01-01

    Electrochemical dechlonnafion of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature.Palladium/foam-nickel (Pd/foam-Ni) and palladium/polymeric pyrrole film/foam-nickel (Pd/PPy/foam-Ni)composite electrodes which provided catalytic surface for reductive dechiorination of chloroform in aqueous solution were prepared using an electrodepositing method.Scanning electron microscope (SEM) micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode.The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 rain,which is much higher than that of Pd/foam-Ni electrode.

  13. Formation of Carbonized Polystyrene Sphere/hemisphere Shell Arrays by Ion Beam Irradiation and Subsequent Annealing or Chloroform Treatment

    Science.gov (United States)

    Song, Xianyin; Dai, Zhigao; Xiao, Xiangheng; Li, Wenqing; Zheng, Xudong; Shang, Xunzhong; Zhang, Xiaolei; Cai, Guangxu; Wu, Wei; Meng, Fanli; Jiang, Changzhong

    2015-01-01

    Heat-resistant two-dimensional (2D) sphere/hemisphere shell array is significant for the fabrication of novel nanostructures. Here large-area, well-ordered arrays of carbonized polystyrene (PS) hollow sphere/hemisphere with controlled size and morphology are prepared by combining the nanosphere self-assembly, kV Ag ion beam modification, and subsequent annealing or chloroform treatment. Potential mechanisms for the formation and evolution of the heat-resistant carbonized PS spherical shell with increasing ion fluence and energy are discussed. Combined with noble metal or semiconductor, these modified PS sphere arrays should open up new possibilities for high-performance nanoscale optical sensors or photoelectric devices. PMID:26640125

  14. Effects of chloroformic extracts from washed and unwashed papaya seeds (Carica papaya) on the sperm concentration of dogs.

    Science.gov (United States)

    Ortega-Pacheco, A; Jiménez-Coello, M; Gutiérrez-Blanco, E; Acosta-Viana, K Y; Guzmán-Marín, E; Zavala-Sánchez, M A; Montalvo-Beltrán, N E; Pérez-Gutiérrez, M S

    2010-12-01

    Papaya seeds (Carica papaya Linn) have been found to have a significant effect on sperm characteristics in some mammals, including humans, but no studies have investigated the effects on dogs. In the present study, a significant decrease in sperm concentration was observed in a group of dogs treated with extracts from washed papaya seeds, but no decrease was observed in the group of dogs treated with non-washed seeds. An important effect of extract components from washed seeds such as fatty acids is probably involved in the reduction of sperm production because of Sertoli cell damage, as has been suggested for langur monkeys. Dilution of the active components in the non-washed papaya seeds or interference with some of the components may reduce the expected effect on spermatogenesis. This first report on the effects of a chloroformic extract of papaya seeds in dogs suggests that an increased dose is necessary to achieve azoospermia.

  15. Inductively coupled plasma torch efficiency at atmospheric pressure for organo-chlorine liquid waste removal: Chloroform destruction in oxidative conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kamgang-Youbi, Georges, E-mail: kamyougeo@yahoo.fr [French Atomic Commission-CEA, Marcoule-DTCD/SCDV/LPIC, BP 17171, 30207 Bagnols-Sur-Cèze Cedex (France); Department of Inorganic Chemistry, The University of Yaounde I, P.O Box, 812 Yaounde (Cameroon); Poizot, Karine; Lemont, Florent [French Atomic Commission-CEA, Marcoule-DTCD/SCDV/LPIC, BP 17171, 30207 Bagnols-Sur-Cèze Cedex (France)

    2013-01-15

    Highlights: ► Inductively plasma torch is used for the decomposition of organochlorine molecule. ► We examine the impact of liquid water substitution by oxygen gas as oxidant. ► Complete and safe decomposition is achieved with the presence of oxygen. ► The energy efficiency and capabilities of process are better with O{sub 2} than H{sub 2}O. -- Abstract: The performance of a plasma reactor for the degradation of chlorinated hydrocarbon waste is reported. Chloroform was used as a target for a recently patented destruction process based using an inductive plasma torch. Liquid waste was directly injected axially into the argon plasma with a supplied power of ∼4 kW in the presence of oxygen as oxidant and carrier gas. Decomposition was performed at CHCl{sub 3} feed rates up to 400 g h{sup −1} with different oxygen/waste molar ratios, chloroform destruction was obtained with at least 99% efficiency and the energy efficiency reached 100 g kWh{sup −1}. The conversion end products were identified and assayed by online FTIR spectroscopy (CO{sub 2}, HCl and H{sub 2}O) and redox titration (Cl{sub 2}). Considering phosgene as representative of toxic compounds, only very small quantities of toxics were released (<1 g h{sup −1}) even with high waste feed rates. The experimental results were very close to the equilibrium composition predicted by thermodynamic calculations. At the bottom of the reactor, the chlorinated acids were successfully trapped in a scrubber and transformed into mineral salts, hence, only CO{sub 2} and H{sub 2}O have been found in the final off-gases composition.

  16. Revisiting the Regenerative Possibilities of Ortiz

    Science.gov (United States)

    Duques, Matthew

    2004-01-01

    The author of this article revisits Simon Ortiz's poem, "From Sand Creek," in which the latter can in so few words convey both the horrific tragedy of conquest and colonization, while at the same time find a space for possibility, a means for recovery that is never about forgetting but always occurs as a kind of recuperative remembering. Ortiz…

  17. Topological string theory revisited I: The stage

    Science.gov (United States)

    Jia, Bei

    2016-08-01

    In this paper, we reformulate topological string theory using supermanifolds and supermoduli spaces, following the approach worked out by Witten (Superstring perturbation theory revisited, arXiv:1209.5461). We intend to make the construction geometrical in nature, by using supergeometry techniques extensively. The goal is to establish the foundation of studying topological string amplitudes in terms of integration over appropriate supermoduli spaces.

  18. Coccolithophorids in polar waters: Calciarcus spp. revisited

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Østergaard, Jette B.

    2014-01-01

    The genus Calciarcus is revisited here with the purpose of providing, based on additional sampling from both polar regions, an update on species diversity and morphology that can serve as a reference for future work. The geographic realm of the genus is significantly widened and a case is built...

  19. Fine structure of the butterfly diagram revisited

    Science.gov (United States)

    Major, Balázs

    The latitudinal time distribution of sunspots (butterfly diagram) was studied by Becker (1959) and Antalová & Gnevyshev (1985). Our goal is to revisit these studies. In the first case we check whether there is a poleward migration in sunspot activity. In the second case we confirm the results, and make more quantitative statements concerning their significance and the position of the activity peaks.

  20. The Rotating Morse-Pekeris Oscillator Revisited

    Science.gov (United States)

    Zuniga, Jose; Bastida, Adolfo; Requena, Alberto

    2008-01-01

    The Morse-Pekeris oscillator model for the calculation of the vibration-rotation energy levels of diatomic molecules is revisited. This model is based on the realization of a second-order exponential expansion of the centrifugal term about the minimum of the vibrational Morse oscillator and the subsequent analytical resolution of the resulting…

  1. Revisiting Basic Counseling Skills with Children

    Science.gov (United States)

    Van Velsor, Patricia

    2004-01-01

    Counseling with children can be challenging for counselors whose training focused on adult clients. The purpose of this article is to offer information to counselors seeking to improve their skills with children, revisiting a topic discussed in an earlier Journal of Counseling & Development article by P. Erdman and R. Lampe (1996). Examples of…

  2. Revisiting the 1761 Transatlantic Tsunami

    Science.gov (United States)

    Baptista, Maria Ana; Wronna, Martin; Miranda, Jorge Miguel

    2016-04-01

    The tsunami catalogs of the Atlantic include two transatlantic tsunamis in the 18th century the well known 1st November 1755 and the 31st March 1761. The 31st March 1761 earthquake struck Portugal, Spain, and Morocco. The earthquake occurred around noontime in Lisbon alarming the inhabitants and throwing down ruins of the past 1st November 1755 earthquake. According to several sources, the earthquake was followed by a tsunami observed as far as Cornwall (United Kingdom), Cork (Ireland) and Barbados (Caribbean). The analysis of macroseismic information and its compatibility with tsunami travel time information led to a source area close to the Ampere Seamount with an estimated epicenter circa 34.5°N 13°W. The estimated magnitude of the earthquake was 8.5. In this study, we revisit the tsunami observations, and we include a report from Cadiz not used before. We use the results of the compilation of the multi-beam bathymetric data, that covers the area between 34°N - 38°N and 12.5°W - 5.5°W and use the recent tectonic map published for the Southwest Iberian Margin to select among possible source scenarios. Finally, we use a non-linear shallow water model that includes the discretization and explicit leap-frog finite difference scheme to solve the shallow water equations in the spherical or Cartesian coordinate to compute tsunami waveforms and tsunami inundation and check the results against the historical descriptions to infer the source of the event. This study received funding from project ASTARTE- Assessment Strategy and Risk Reduction for Tsunamis in Europe a collaborative project Grant 603839, FP7-ENV2013 6.4-3

  3. In Vivo Antiprotozoal Activity of the Chloroform Extract from Carica papaya Seeds against Amastigote Stage of Trypanosoma cruzi during Indeterminate and Chronic Phase of Infection

    Directory of Open Access Journals (Sweden)

    Matilde Jimenez-Coello

    2014-01-01

    Full Text Available In order to evaluate the antiprotozoal activity of the chloroform extract of Carica papaya seeds during the subacute and chronic phase of infection of Trypanosoma cruzi, doses of 50 and 75 mg/kg were evaluated during the subacute phase, including a mixture of their main components (oleic, palmitic, and stearic acids. Subsequently, doses of 50 and 75 mg/kg in mice during the chronic phase of infection (100 dpi were also evaluated. It was found that chloroform extract was able to reduce the amastigote nests numbers during the subacute phase in 55.5 and 69.7% (P > 0.05 as well as in 56.45% in animals treated with the mixture of fatty acids. Moreover, the experimental groups treated with 50 and 75 mg/kg during the chronic phase of the infection showed a significant reduction of 46.8 and 53.13% respectively (P < 0.05. It is recommended to carry out more studies to determine if higher doses of chloroformic extract or its administration in combination with other antichagasic drugs allows a better response over the intracellular stage of T. cruzi in infected animal models and determine if the chloroform extract of C. papaya could be considered as an alternative for treatment during the indeterminate and chronic phase of the infection.

  4. Expanded metabolite coverage of Saccharomyces cerevisiae extract through improved chloroform/methanol extraction and tert-butyldimethylsilyl derivatization

    DEFF Research Database (Denmark)

    Khoomrung, Sakda; Martinez, Jose L.; Tippmann, Stefan;

    2015-01-01

    We present an improved extraction and derivatization protocol for GC-MS analysis of amino/non-amino acids in Saccharomyces cerevisiae. Yeast cells were extracted with chloroform: aqueous-methanol (1:1, v/v) and the resulting non-polar and polar extracts combined and dried for derivatization. Pola...

  5. CYTOTOXIC ACTIVITY OF N-HEXANE, CHLOROFORM AND CARBON TETRACHLORIDE FRACTIONS OF THE ETHANOLIC EXTRACT OF LEAVES AND STEMS OF BACCAUREA RAMIFLORA (LOUR..

    Directory of Open Access Journals (Sweden)

    Apurba Sarker Apu et al.

    2012-03-01

    Full Text Available The purpose of the study was to find out the cytotoxic activity of the n-hexane, chloroform and carbon tetrachloride fractions of the ethanolic extracts of the leaves and stems of Baccaurea ramiflora (Lour.. Ethanolic extracts of the leaves and stems of Baccaurea ramiflora were subjected to solvent-solvent partitioning using n-hexane, chloroform and carbon tetrachloride to obtain n-hexane leaves fraction, chloroform leaves fraction, n-hexane stems fraction, chloroform stems fraction and carbon tetrachloride stems fraction. Each fraction was assayed for their cytotoxic effect using brine shrimp lethality bioassay. Among the fractions, the n-hexane fractions of leaves and stems showed significant cytotoxic effects having LC50 values of 7.79 µg/ml (95% confidence interval 6.48-9.37 and 5.78 µg/ml (95% confidence interval 4.76-6.99 respectively as compared to vincristine sulfate (LC50= 2.81 µg/ml (95% confidence interval 1.97-4.01 which was used as positive control. The results support the traditional uses of B. ramiflora for various medicinal purposes and thus demand the isolation and identification of active principles and thorough bioassay.

  6. Revisiting the Diffusion Problem in a Capillary Tube Geometry

    CERN Document Server

    Sullivan, Eric

    2012-01-01

    The present work revisits the problem of modeling diffusion above a stagnant liquid interface in a capillary tube geometry. In this revisitation we elucidate a misconception found in the classical model proposed by Bird et. al. Furthermore, we propose alternative explanations for thermally forced diffusion and provide a description of natural convection in the absence of forcing terms.

  7. Coccolithophorids in polar waters: Wigwamma spp. revisited

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Østergaard, Jette B.; Heldal, Mikal

    2013-01-01

    A contingent of weakly calcified coccolithophorid genera and species were described from polar regions almost 40 years ago. In the interim period a few additional findings have been reported enlarging the realm of some of the species. The genus Wigwamma is revisited here with the purpose of provi......A contingent of weakly calcified coccolithophorid genera and species were described from polar regions almost 40 years ago. In the interim period a few additional findings have been reported enlarging the realm of some of the species. The genus Wigwamma is revisited here with the purpose...... of providing, based on additional sampling from both polar regions, an update on species morphology, life history events and biogeography that can serve as a reference for the future. A new genus, Pseudowigwamma gen. nov. is described to accommodate Wigwamma scenozonion, a species which critically deviates...

  8. Geochemical characteristics of light hydrocarbons in cracking gases from chloroform bitumen A,crude oil and its fractions

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The composition characteristics of light hydrocarbons from crude oil,chloroform bitumen A,saturated hydrocarbon fraction,aromatic hydrocarbon fraction,and asphaltene fraction during cracking have been studied systematically. The results revealed that the content of n-alkanes,branched alkanes and cycloalkanes in light hydrocarbons from the samples gradually decreased as the simulation temperature increased,and finally almost depleted completely,while the abundance of methane,benzene and its homologues increased obviously and became the main products. The ratios of benzene/n-hexane and toluene/n-heptane can be used as measures for oil cracking levels. Variation characteristics of maturity parameters of light hydrocarbons,for example,iC4/nC4,iC5/nC5,isoheptane value,2,2-DMC4/nC6,and 2-MC6+3-MC6/nC7 for different samples with increasing pyrolysis temperature,are consistent with those in petroleum reservoirs,indicating that these parameters may be efficient maturity index.

  9. Fenton process for degradation of selected chlorinated aliphatic hydrocarbons exemplified by trichloroethylene, 1,1-dichloroethylene and chloroform

    Institute of Scientific and Technical Information of China (English)

    Zhimin QIANG; Weiwei BEN; ChinPao HUANG

    2008-01-01

    The degradation of selected chlorinated ali-phatic hydrocarbons (CAHs) exemplified by trichloroethy-lene (TCE), 1,1-dichloroethylene (DCE), and chloroform (CF) was investigated with Fenton oxidation process. The results indicate that the degradation rate was primarily affected by the chemical structures of organic contami-nants. Hydroxyl radicals (·OH) preferred to attack the organic contaminants with an electron-rich structure such as chlorinated alkenes (i.e., TCE and DCE). The dosing mode of Fenton's reagent, particularly of Fe2+, significantly affected the degradation efficiency of studied organic compound. A new "time-squared" kinetic model, C = Coexp(-kobst2), was developed to express the degrada-tion kinetics of selected CAHs. This model was applicable to TCE and DCE, but inapplicable to CF due to their varied reaction rate constants towards ·OH. Chloride release was monitored to examine the degree of dechlorina- tion during the oxidation of selected CAHs. TCE was more easily dechlorinated than DCE and CF. Dichloroacetic acid (DCAA) was identified as the major reaction intermediate in the oxidation of TCE, which could be completely removed as the reaction proceeded. No reaction intermedi- ates or byproducts were identified in the oxidation of DCE and CF. Based on the identified intermediate, the reaction mechanism of TCE with Fenton's reagent was proposed.

  10. Calculated Third Order Rate Constants for Interpreting the Mechanisms of Hydrolyses of Chloroformates, Carboxylic Acid Halides, Sulfonyl Chlorides and Phosphorochloridates

    Directory of Open Access Journals (Sweden)

    T. William Bentley

    2015-05-01

    Full Text Available Hydrolyses of acid derivatives (e.g., carboxylic acid chlorides and fluorides, fluoro- and chloroformates, sulfonyl chlorides, phosphorochloridates, anhydrides exhibit pseudo-first order kinetics. Reaction mechanisms vary from those involving a cationic intermediate (SN1 to concerted SN2 processes, and further to third order reactions, in which one solvent molecule acts as the attacking nucleophile and a second molecule acts as a general base catalyst. A unified framework is discussed, in which there are two reaction channels—an SN1-SN2 spectrum and an SN2-SN3 spectrum. Third order rate constants (k3 are calculated for solvolytic reactions in a wide range of compositions of acetone-water mixtures, and are shown to be either approximately constant or correlated with the Grunwald-Winstein Y parameter. These data and kinetic solvent isotope effects, provide the experimental evidence for the SN2-SN3 spectrum (e.g., for chloro- and fluoroformates, chloroacetyl chloride, p-nitrobenzoyl p-toluenesulfonate, sulfonyl chlorides. Deviations from linearity lead to U- or V-shaped plots, which assist in the identification of the point at which the reaction channel changes from SN2-SN3 to SN1-SN2 (e.g., for benzoyl chloride.

  11. ConocoPhillips’ share price model revisited

    OpenAIRE

    Kitov, Ivan

    2012-01-01

    Three years ago we found a statistically reliable link between ConocoPhillips’ (NYSE: COP) stock price and the difference between the core and headline CPI in the United States. In this article, the original relationship is revisited with new data available since 2009. The agreement between the observed monthly closing price (adjusted for dividends and splits) and that predicted from the CPI difference is confirmed. The original quantitative link is validated. In order to improve the accurac...

  12. Spine revisited: Principles and parlance redefined

    Directory of Open Access Journals (Sweden)

    Kothari M

    2005-01-01

    Full Text Available A revised appreciation of the evolution and the nature of bone in general and of vertebrae in particular, allows revisiting the human spine to usher in some new principles and more rational parlance, that embody spine′s phylogeny, ontogeny, anatomy and physiology. Such an approach accords primacy to spine′s soft-tissues, and relegates to its bones a secondary place.

  13. The Actinide Transition Revisited by Gutzwiller Approximation

    Science.gov (United States)

    Xu, Wenhu; Lanata, Nicola; Yao, Yongxin; Kotliar, Gabriel

    2015-03-01

    We revisit the problem of the actinide transition using the Gutzwiller approximation (GA) in combination with the local density approximation (LDA). In particular, we compute the equilibrium volumes of the actinide series and reproduce the abrupt change of density found experimentally near plutonium as a function of the atomic number. We discuss how this behavior relates with the electron correlations in the 5 f states, the lattice structure, and the spin-orbit interaction. Our results are in good agreement with the experiments.

  14. BHQ revisited (2): Texture development

    Science.gov (United States)

    Kilian, Rüdiger; Heilbronner, Renée

    2016-04-01

    appears that grains can be unfavourably oriented for glide despite their c-axis direction falling in those positions which were used in the "classical" interpretation. Additionally, it turns out that grain-scale dispersion axes can be used to describe the kinematic behaviour in a more consistent way compared to the rotations axes obtained from intragranular misorientations in the range of 2-10°. The implications derived from the experimental data set will be compared to data obtained from natural quartz mylonites which formed in a comparable recrystallization regime. This is the companion poster to "BHQ revisited (I) looking at grain size" where the development of the dynamically recrystallized grain size is addressed. Reference cited: Heilbronner, R., and J. Tullis (2006), Evolution of c axis pole figures and grain size during dynamic recrystallization: Results from experimentally sheared quartzite, J. Geophys. Res., 111, B10202, doi:10.1029/2005JB004194.

  15. Isobaric vapor liquid equilibria data for the binary system (glycidyl butyrate + acetone, glycidyl butyrate + carbon tetrachloride, glycidyl butyrate + chloroform) at atmospheric pressure 101 kPa

    Science.gov (United States)

    Huang, Qiang; Meng, Qingyi; Ban, Chunlan; Zhang, Rui; Gao, Yingyu

    2016-09-01

    Isobaric vapor liquid equilibria (VLE) for the binary mixtures of glycidyl butyrate(1) + acetone(2), glycidyl butyrate(1) + carbon tetrachloride(2) and glycidyl butyrate(1) + chloroform(2) at 101 kPa were studied. The experimental data were satisfactorily correlated with the models of Wilson, NRTL and UNIQUAC activity coefficients. The activity coefficients for the equilibrium data were obtained by the nonlinear least square method. The average relative deviations between experimental temperatures and calculated temperatures by the Wilson, NRTL and UNIQUAC models were 0.16, 0.16, 0.23% for glycidyl butyrate(1) + chloroform( 2), 0.38, 0.12, 0.27% for glycidylbutyrate(1) + carbon tetrachloride(2), and 0.67, 0.13, 0.54% for glycidyl butyrate(1) + acetone(2). Azeotrope behavior was not found for these systems. The thermodynamic consistency of the correlations was checked by the Herrington's area test.

  16. An in vivo and in vitro analysis of free radical scavenging potential possessed by Desmodium gangeticum chloroform root extract: interpretation by gsms.

    Science.gov (United States)

    Srivats, Shyam; Ramakrishnan, Gomathi; Paddikkala, Jose; Kurian, Gino Andrew

    2012-01-01

    In the present study, the effect of DG chloroform root extract was assessed on isolated rat heart and in-vitro antioxidant models. Ischemia reperfusion injury was experimentally induced by using Langendroff apparatus. The free radical scavenging potential was studied in vitro by using different antioxidant models such as DPPH, super oxide scavenging activity, hydroxide scavenging activity and nitric oxide scavenging activity. Both experimental approaches not only substantiate its antioxidant potential but also the cardio-protection imparted by the extract. The cardio-stimulatory effects were investigated for the extract by treating it as a pre-conditioning agent against myocardial ischemia reperfusion injury. The improved antioxidant status of the myocardium indirectly predicts reduced oxidative stress mediated by ischemic reperfusion with evident reduction of infarct size determined by cardiac marker protein. These findings indicate that DG chloroform root extract may possess therapeutic potential against ischemia reperfusion injury. PMID:22186306

  17. Investigating migration inhibition and apoptotic effects of Fomitopsis pinicola chloroform extract on human colorectal cancer SW-480 cells.

    Directory of Open Access Journals (Sweden)

    Yaqin Wang

    Full Text Available BACKGROUND: Fomitopsis pinicola (Sw. Ex Fr.m Karst (FPK which belongs to the Basidiomycota fungal class is one of the most popular medical fungi in China. It has been used for many diseases: cancer, heart diseases, diabetes and so on. However, little study on the pro-apoptotic effect and migration inhibition of FPK chloroform extract (FPKc has been reported and the possible involved mechanism has not been illuminated. METHODOLOGY/PRINCIPAL FINDINGS: Chemical analysis was performed by HPLC which showed ergosterol (ES concentration was 105 µg/mg. MTT assay revealed that FPKc could selectively inhibit SW-480 cells viability with the IC50 of 190.28 µg/ml. Wound healing and transwell assay indicated that FPKc could inhibit the migration of SW-480 cells obviously, FPKc could also dramatically decreased the matrix metalloproteinases-2, 9 (MMP-2 and MMP-9 expression. Annexin V-FITC/PI staining, nuclear Hoechst 33342 staining and DNA fragmentation analysis revealed that FPKc and ES could induce SW-480 cells apoptosis. The apoptosis process closely involved in ROS accumulation and depletion of GSH, activation of caspase 3, poly (ADP-ribose polymerase (PARP degradation. FPKc could also up-regulate P53 expression and thus lead to G1 phase arrest. When SW-480 cells were pretreated with N-acetylcysteine (NAC, the ROS generation, cell viability and apoptotic ratio were partially declined, which indicated that ROS was vertical in the pro-apoptosis process induced by FPKc. Moreover, in the whole process, ES which has been previously found in FPKc had the similar effect to FPKc. Thus we could conclude that ES, as one of the highest abundant components in FPKc, might also be one of the active constituents. CONCLUSION/SIGNIFICANCE: FPKc could inhibit the migration of SW-480 cells, induce SW-480 cells G1 phase arrest and cause ROS-mediated apoptosis effect. And ES might be one of the effective constituents in the whole process.

  18. Microcalorimetric Study on the Oscillating System of Two-phase Reaction of Aqueous Acid with Primary Amine in Chloroform

    Institute of Scientific and Technical Information of China (English)

    ZHANG,Hong-Lin; YU,Xiu-Fang; LU,Cheng-Xue; SUN,Si-Xiu; GUO,Guo-Hua; FU,Xun

    2003-01-01

    It has been found that the two-phase reactions of aqueous HCl,HOAc or H3PO4 with primary amine N1923 in chloroform are oscillating reactions. Their power-time curves were measured by the titration microcalorimetric method, and the induction period (tin).The first oscillating period (tp.1) and the second oscillating period(tp.2 ) were determined.The apparent activating parameters and the orders of the oscillating systems were calculated and the following relationships were established: for the oscillating system of hydrochloric acid tin∝c0.147HCIexp(1.35×103/T),.tp.1∝c0.241HCI·exp(4.33×103/T),tp.2∝c0.290HCIexp(5.59×103/T);for the oscillating system of acetic acid, tm∝c0.883HOAcexp(2.32×103/T),tp.1∝c0.399HOAc·exp(4.50×103/T),tp.2∝c0.301HOAcexp(5.88×103/T),for the oscillating system of phosphoric acid, tim∝c1.14H3PO4exp(7.70×104]T),tp.1∝c1.42H3PO4exp(1.14×104/T),tp.2∝c1.47H3PO4exp(1.27×104/T).

  19. Anticancer activity of chloroform extract and sub-fractions of nepeta deflersiana on human breast and lung cancer cells: an in vitro cytotoxicity assessment

    Directory of Open Access Journals (Sweden)

    Mai M Al-Oqail

    2015-01-01

    Full Text Available Background: Cancer is one of the major causes of death worldwide. The plant-derived natural products have received considerable attention in recent years due to their diverse pharmacological properties including anticancer effects. Nepeta deflersiana (ND is used in the folk medicine as antiseptic, carminative, antimicrobial, antioxidant, and for treating rheumatic disorders. However, the anticancer activity of ND chloroform extract has not been explored so far. Objectives: The present study was aimed to investigate the anticancer activities of chloroform Nepeta deflersiana extract and various sub-fractions (ND-1-ND-15 of ND against human breast cancer cells (MCF-7 and human lung cancer cells (A-549. Materials and Methods: The 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide and neutral red uptake assays, and cellular morphological alterations using phase contrast light microscope were studied. Cells were exposed with 10-1000 mg/ml of sub-fractions of ND for 24 h. Results: Results showed that selected sub-fractions of the chloroform extract significantly reduced the cell viability of MCF-7 and A-549 cells, and altered the cellular morphology in a concentration-dependent manner. Among the sub-fractions, ND-10 fraction showed relatively higher cytotoxicity compared to other fractions whereas, ND-1 did not cause any cytotoxicity even at higher concentrations. The A-549 cells were found to be more sensitive to growth inhibition by all the extracts as compared to the MCF-7 cells. Conclusion: The present study provides preliminary screening of anticancer activities of chloroform extract and sub-fractions of ND, which can be further used for the development of a potential therapeutic anticancer agent.

  20. RNA extraction from various recalcitrant plant tissues with a cethyltrimethylammonium bromide-containing buffer followed by an acid guanidium thiocyanate-phenol-chloroform treatment.

    Science.gov (United States)

    Suzuki, Yuji; Mae, Tadahiko; Makino, Amane

    2008-07-01

    High-quality total RNA was extracted using a cethyltrimethylammonium bromide-containing buffer followed by an acid guanidium thiocyanate-phenol-chloroform treatment from recalcitrant plant tissues such as tree leaves (pine, Norway spruce, ginkgo, Japanese cedar, rose), flowers (rose, Lotus japonicus) and storage tissues (seeds of Lotus japonicus and rice, sweet potato tuber, banana fruit). This protocol greatly reduced the time required for RNA extraction.

  1. Inhibiting effects of chloroform and ethanol on GMO detection%三氯甲烷和乙醇对转基因成分检测的抑制

    Institute of Scientific and Technical Information of China (English)

    王东; 宋君; 尹全; 陶李; 雷绍荣; 刘勇

    2011-01-01

    The different concentration of chloroform and ethanol were designed in the PCR of lectin gene of genetically modified soybean (GTS-40-3-2) in order to investigate the inhibitory effects of chloroform and ethanol on the quality PCR of genetically modified organism detection. The results showed PCR was inhibited when the concentration of chloroform was greater than or equal to 3.77 mol/L and when that of ethanol was greater than 1.39 mol/L in the reaction system.%该文以抗除草剂(CP4-EPSPS)转基因大豆GTS-40-3 -2为材料,在Lectin基因的扩增体系中设置不同浓度梯度的三氯甲烷、乙醇,模拟这2种有机试剂残留,探讨三氯甲烷、乙醇在转基因成分检测中的抑制作用.结果表明:在PCR反应体系中三氯甲烷的摩尔浓度≥3.77 mol/L时,能完全抑制PCR反应;乙醇的摩尔浓度>1.39 mol/L时,PCR反应彻底被抑制.

  2. Reliable solution processed planar perovskite hybrid solar cells with large-area uniformity by chloroform soaking and spin rinsing induced surface precipitation

    International Nuclear Information System (INIS)

    A solvent soaking and rinsing method, in which the solvent was allowed to soak all over the surface followed by a spinning for solvent draining, was found to produce perovskite layers with high uniformity on a centimeter scale and with much improved reliability. Besides the enhanced crystallinity and surface morphology due to the rinsing induced surface precipitation that constrains the grain growth underneath in the precursor films, large-area uniformity with film thickness determined exclusively by the rotational speed of rinsing spinning for solvent draining was observed. With chloroform as rinsing solvent, highly uniform and mirror-like perovskite layers of area as large as 8 cm × 8 cm were produced and highly uniform planar perovskite solar cells with power conversion efficiency of 10.6 ± 0.2% as well as much prolonged lifetime were obtained. The high uniformity and reliability observed with this solvent soaking and rinsing method were ascribed to the low viscosity of chloroform as well as its feasibility of mixing with the solvent used in the precursor solution. Moreover, since the surface precipitation forms before the solvent draining, this solvent soaking and rinsing method may be adapted to spinless process and be compatible with large-area and continuous production. With the large-area uniformity and reliability for the resultant perovskite layers, this chloroform soaking and rinsing approach may thus be promising for the mass production and commercialization of large-area perovskite solar cells

  3. The Chloroform Fraction of Carpinus tschonoskii Leaves Inhibits the Production of Inflammatory Mediators in HaCaT Keratinocytes and RAW264.7 Macrophages.

    Science.gov (United States)

    Kang, Gyeoung-Jin; Kang, Na-Jin; Han, Sang-Chul; Koo, Dong-Hwan; Kang, Hee-Kyoung; Yoo, Byoung-Sam; Yoo, Eun-Sook

    2012-12-01

    Inflammation is the immune system's response to infection and injury-related disorders, and is related to pro-inflammatory factors (NO, PGE2, cytokines, etc.) produced by inflammatory cells. Atopic dermatitis (AD) is a representative inflammatory skin disease that is characterized by increasing serum levels of inflammatory chemokines, including macrophage-derived chemokine (MDC). Carpinus tschonoskii is a member of the genus Carpinus. We investigated the anti-inflammatory activity of C. tschonoskii by studying the effects of various solvent fractions prepared from its leaves on inflammatory mediators in HaCaT and RAW264.7 cells. We found that the chloroform fraction of C. tschonoskii inhibited MDC at both the protein and mRNA levels in HaCaT cells, acting via the inhibition of STAT1 in the IFN-γ signaling pathway. In addition, the chloroform fraction significantly suppressed the expression of inflammatory factors induced by lipopolysaccharide stimulation, except COX-2 and TNF-α. These results suggest that the chloroform fraction of C. tschonoskii leaves may include a component with potential anti-inflammatory activity. PMID:24278618

  4. Determination of vanadium in stainless steel and Ni-base alloys by NBPHA spectrophotometric method combined with chloroform extraction separation in media of sulfuric-hydrofluoric acid

    International Nuclear Information System (INIS)

    A new method of rapid vanadium analysis was proposed. In this method, vanadium is directly extracted and determined from sample solutions in sulfuric-hydrofluoric acid. The interference of the coexisting elements can be ignored in this method. Take one gram of sample into a 200 ml beaker, and add 30 ml of aqua regia. Then heat and dissolve it, and add 14 ml of sulfuric acid (1+1) and 5 ml of phosphoric acid. After cooling, dissolve the salts with a small amount of water. Thereafter, transfer it with use of water into a polyethylene separatory funnel, add 10 ml of 46% hydrofluoric acid, and dilute to 50 ml. Then, add 4 ml iron (II) ammonium sulfate solution (10%) and mix it thoroughly. Allow to stand for two or three minutes, add 10 ml of 45% ammonium persulfate solution and mix it thoroughly again. Allow to stand for about five minutes. Then, add exactly 20 ml of BPHA-chloroform solution (0.1%) and shake and mix it vigorously for two minutes. After a while, transfer the chloroform complex into a 10 mm cell through a piece of absorbent cotton. Then, determine vanadium by measuring the absorbance at the wave length of 530 nm against a chloroform reference. This method can be applicable to the analysis of vanadium in other metals and alloys than stainless steel and Ni-base alloys. (Iwakiri, K.)

  5. The Faraday effect revisited: General theory

    DEFF Research Database (Denmark)

    Cornean, Horia Decebal; Nenciu, Gheorghe; Pedersen, Thomas Garm

    2006-01-01

    This paper is the first in a series revisiting the Faraday effect, or more generally, the theory of electronic quantum transport/optical response in bulk media in the presence of a constant magnetic field. The independent electron approximation is assumed. At zero temperature and zero frequency......, if the Fermi energy lies in a spectral gap, we rigorously prove theWidom-Streda formula. For free electrons, the transverse conductivity can be explicitly computed and coincides with the classical result. In the general case, using magnetic perturbation theory, the conductivity tensor is expanded in powers...

  6. Polynomial chaotic inflation in supergravity revisited

    Directory of Open Access Journals (Sweden)

    Kazunori Nakayama

    2014-10-01

    Full Text Available We revisit a polynomial chaotic inflation model in supergravity which we proposed soon after the Planck first data release. Recently some issues have been raised in Ref. [12], concerning the validity of our polynomial chaotic inflation model. We study the inflaton dynamics in detail, and confirm that the inflaton potential is very well approximated by a polynomial potential for the parameters of our interest in any practical sense, and in particular, the spectral index and the tensor-to-scalar ratio can be estimated by single-field approximation. This justifies our analysis of the polynomial chaotic inflation in supergravity.

  7. Coccolithophorids in polar waters: Pappomonas spp. revisited

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Østergaard, J.B.

    2014-01-01

    A contingent of weakly calcified coccolithophorid genera and species were described from polar regions almost 40 years ago. In the interim period a few additional findings have been reported enlarging the realm of some of the species. The genus Pappomonas is revisited here with the purpose...... of providing, based on additional sampling from both polar regions, an update on species morphology, life history aspects and biogeography that can serve as a reference for the future. The examination of a substantial number of cells unequivocally supports the elevation to species level of P. borealis stat...

  8. Coccolithophorids in polar waters: Trigonaspis spp. revisited

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Østergaard, Jette B.

    2015-01-01

    A group of weakly calcified coccolithophorid genera and species were described from polar regions several decades ago. In the interim period a few additional findings have been reported adding to the morphological and biogeographical databases of some of the species. The holococcolithophorid genus...... Trigonaspis is revisited here with the purpose of providing, based on additional sampling from both polar regions, an update on species morphology, life history aspects and biogeography. The genus Trigonaspis as currently circumscribed comprises four taxa – two from each polar region. The triangular plates...

  9. Sloan Digital Sky Survey Photometric Calibration Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Marriner, John; /Fermilab

    2012-06-29

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  10. Resolution of Reflection Seismic Data Revisited

    DEFF Research Database (Denmark)

    Hansen, Thomas Mejer; Mosegaard, Klaus; Zunino, Andrea

    wavelength of the wavelet within the thin layer. Using a simple thin-layer parameterization Widess (1973) demonstrated that thin layers with thickness less that around λb/8 cannot be resolved from seismic data independent of the noise level. This has results since been widely adopted as a commonly accepted...... lower vertical resolution of reflection seismic data. In the following we will revisit think layer model and demonstrate that there is in practice no limit to the vertical resolution using the parameterization of Widess (1973), and that the vertical resolution is limited by the noise in the data...

  11. Revisiting Fermat's Factorization for the RSA Modulus

    CERN Document Server

    Gupta, Sounak

    2009-01-01

    We revisit Fermat's factorization method for a positive integer $n$ that is a product of two primes $p$ and $q$. Such an integer is used as the modulus for both encryption and decryption operations of an RSA cryptosystem. The security of RSA relies on the hardness of factoring this modulus. As a consequence of our analysis, two variants of Fermat's approach emerge. We also present a comparison between the two methods' effective regions. Though our study does not yield a new state-of-the-art algorithm for integer factorization, we believe that it reveals some interesting observations that are open for further analysis.

  12. Re-visiting the Piper Alpha accident

    OpenAIRE

    Dykesteen, Mette Kahrs

    2013-01-01

    The main objective of this thesis has been to re-visit the Piper Alpha accident using the latest version of the FLACS simulation code. In 1988/89 simulations of the gas explosion in the C Module of Piper Alpha were performed by Jan Roar Bakke and Idar Storvik at Christian Michelsen Institute, in conjunction with the investigation after the accident. For these simulations the computer code FLACS was used [1, 2]. In this thesis, the same simulation cases have been looked into, and the results o...

  13. Sloan Digital Sky Survey Photometric Calibration Revisited

    Science.gov (United States)

    Marriner, J.

    2016-05-01

    The Sloan Digital Sky Survey calibration is revisited to obtain the most accurate photometric calibration. A small but significant error is found in the flat-fielding of the Photometric telescope used for calibration. Two SDSS star catalogs are compared and the average difference in magnitude as a function of right ascension and declination exhibits small systematic errors in relative calibration. The photometric transformation from the SDSS Photometric Telescope to the 2.5 m telescope is recomputed and compared to synthetic magnitudes computed from measured filter bandpasses.

  14. Sources and occurrence of chloroform and other trihalomethanes in drinking-water supply wells in the United States, 1986-2001

    Science.gov (United States)

    Ivahnenko, Tamara; Zogorski, J.S.

    2006-01-01

    Chloroform and three other trihalomethanes (THMs)--bromodichloromethane, dibromochloromethane, and bromoform--are disinfection by-products commonly produced during the chlorination of water and wastewater. Samples of untreated ground water from drinking-water supply wells (1,096 public and 2,400 domestic wells) were analyzed for THMs and other volatile organic compounds (VOCs) during 1986-2001, or compiled, as part of the U.S. Geological Survey's National Water-Quality Assessment Program. This report provides a summary of potential sources of THMs and of the occurrence and geographical distribution of THMs in samples from public and domestic wells. Evidence for an anthropogenic source of THMs and implications for future research also are presented. Potential sources of THMs to both public and domestic wells include the discharge of chlorinated drinking water and wastewater that may be intentional or inadvertent. Intentional discharge includes the use of municipally supplied chlorinated water to irrigate lawns, golf courses, parks, gardens, and other areas; the use of septic systems; or the regulated discharge of chlorinated wastewater to surface waters or ground-water recharge facilities. Inadvertent discharge includes leakage of chlorinated water from swimming pools, spas, or distribution systems for drinking water or wastewater sewers. Statistical analyses indicate that population density, the percentage of urban land, and the number of Resource Conservation and Recovery Act hazardous-waste facilities near sampled wells are significantly associated with the probability of detection of chloroform, especially for public wells. Domestic wells may have several other sources of THMs, including the practice of well disinfection through shock chlorination, laundry wastewater containing bleach, and septic system effluent. Chloroform was the most frequently detected VOC in samples from drinking-water supply wells (public and domestic wells) in the United States. Although

  15. Ground Zero revisits shape outbreaks: Zika and beyond

    CERN Document Server

    Manrique, Pedro D; Johnson, Neil F

    2016-01-01

    During an infection outbreak, many people continue to revisit Ground Zero - such as the one square mile of Miami involved in the current Zika outbreak- for work, family or social reasons. Public health planning must account for the counterintuitive ways in which this human flow affects the outbreak's duration, severity and time-to-peak. Managing this flow of revisits can allow the outbreak's evolution to be tailored.

  16. The role of brand destination experience in determining revisit intention

    DEFF Research Database (Denmark)

    Mattsson, Jan; Barnes, Stuart; Sørensen, Flemming

    experience, which provides a more holistic and unified view of the brand destination. The research uses a logistic regression model to determine the role of satisfaction and brand experience in determining revisit intentions. The study also examines differences among subgroups and four brand experience sub......-constructs. The findings suggest that brand experience is an important determinant of revisit intentions, but that there is variation among respondent groups. The paper rounds off with conclusions and implications for research and practice....

  17. Influence of Alkaline Treatment on Chloroform Extract of China-Hemp%碱处理对汉麻皮氯仿萃取物的影响

    Institute of Scientific and Technical Information of China (English)

    赵小泷; 杨力生; 金彪; 李荣霞; 周文龙

    2013-01-01

    运用气质联用技术,对汉麻皮的氯仿萃取物进行了测定分析.研究表明,汉麻皮的氯仿萃取物中仍然明显有大麻中的特殊化学成分——四氢大麻酚(THC)存在.四氢大麻酚会在汉麻的普通化学脱胶处理(碱处理)中被有效去除,这说明在汉麻纺织商品中不会含有大麻酚物质,汉麻纺织产品是安全的,同时也说明四氢大麻酚物质可能与汉麻皮的胶类物质有一定的关系.在一定条件下,碱处理60 min后纤维中将不会存在四氢大麻酚.汉麻皮氯仿萃取物中主要还含有十六酸和十八烷酸等物质.%This paper tests and analyzes chloroform extract of China-hemp using gas chromatography-mass spectrography technology. The research shows that the special chemical component in hemp-THC still exists in chloroform extract of China-hemp. THC will be effectively removed in general chemical de-gumming treatment (alkaline treatment) of China-hemp, indicating that China-hemp textile goods do not contain Cannabinol and China-hemp textile products are safe and that THC might have certain relationship with gum substance of China-hemp. Under certain conditions, fiber subject to alkaline treatment for 60 min will not have THC. Chloroform extract of China-hemp also contains hexadecanoic acid and octadecanoic acid etc.

  18. Chloroform Cometabolism by Butane-Grown CF8, Pseudomonas butanovora, and Mycobacterium vaccae JOB5 and Methane-Grown Methylosinus trichosporium OB3b

    OpenAIRE

    Hamamura, N.; Page, C.; Long, T; Semprini, L; Arp, D J

    1997-01-01

    Chloroform (CF) degradation by a butane-grown enrichment culture, CF8, was compared to that by butane-grown Pseudomonas butanovora and Mycobacterium vaccae JOB5 and to that by a known CF degrader, Methylosinus trichosporium OB3b. All three butane-grown bacteria were able to degrade CF at rates comparable to that of M. trichosporium. CF degradation by all four bacteria required O(inf2). Butane inhibited CF degradation by the butane-grown bacteria, suggesting that butane monooxygenase is respon...

  19. Post-Inflationary Gravitino Production Revisited

    CERN Document Server

    Ellis, John; Nanopoulos, Dimitri V; Olive, Keith A; Peloso, Marco

    2016-01-01

    We revisit gravitino production following inflation. As a first step, we review the standard calculation of gravitino production in the thermal plasma formed at the end of post-inflationary reheating when the inflaton has completely decayed. Next we consider gravitino production prior to the completion of reheating, assuming that the inflaton decay products thermalize instantaneously while they are still dilute. We then argue that instantaneous thermalization is in general a good approximation, and also show that the contribution of non-thermal gravitino production via the collisions of inflaton decay products prior to thermalization is relatively small. Our final estimate of the gravitino-to-entropy ratio is approximated well by a standard calculation of gravitino production in the post-inflationary thermal plasma assuming total instantaneous decay and thermalization at a time $t \\simeq 1.2/\\Gamma_\\phi$. Finally, in light of our calculations, we consider potential implications of upper limits on the gravitin...

  20. Revisiting gravitino dark matter in thermal leptogenesis

    CERN Document Server

    Ibe, Masahiro; Yanagida, Tsutomu T

    2016-01-01

    In this paper, we revisit the gravitino dark matter scenario in the presence of the bilinear $R$-parity violating interaction. In particular, we discuss a consistency with the thermal leptogenesis. For a high reheating temperature required for the thermal leptogenesis, the gravitino dark matter tends to be overproduced, which puts a severe upper limit on the gluino mass. As we will show, a large portion of parameter space of the gravitino dark matter scenario has been excluded by combining the constraints from the gravitino abundance and the null results of the searches for the superparticles at the LHC experiments. In particular, the models with the stau (and other charged slepton) NLSP has been almost excluded by the searches for the long-lived charged particles at the LHC unless the required reheating temperature is somewhat lowered by assuming, for example, a degenerated right-handed neutrino mass spectrum.

  1. Revisiting the R νMDM models

    Science.gov (United States)

    Cai, Yi; Schmidt, Michael A.

    2016-05-01

    Combining neutrino mass generation and a dark matter candidate in a unified model has always been intriguing. We revisit the class of R νMDM models, which incorporate minimal dark matter in radiative neutrino mass models based on the one-loop ultraviolet completions of the Weinberg operator. The possibility of an exact accidental Z 2 is completely ruled out in this scenario. We study the phenomenology of one of the models with an approximate Z 2 symmetry. In addition to the Standard Model particles, it contains two real scalar quintuplets, one vector-like quadruplet fermion and a fermionic quintuplet. The neutral component of the fermionic quintuplet serves as a good dark matter candidate which can be tested by the future direct and indirect detection experiments. The constraints from flavor physics and electroweak-scale naturalness are also discussed.

  2. ADHM Revisited: Instantons and Wilson Lines

    CERN Document Server

    Tong, David

    2014-01-01

    We revisit the well-studied D0-D4 system of D-branes and its relationship to the ADHM construction. It is well known that the D0-branes appear as instantons in the D4-brane worldvolume. We add a Wilson line to the D4-brane in the guise of an extended fundamental string and determine how this affects the D0-brane dynamics. As the D0-brane moves in the presence of the Wilson line, it experiences a Lorentz force, proportional to its Yang-Mills gauge connection. From the perspective of the D0-brane quantum mechanics, this force emerges through the ADHM construction of the self-dual gauge connection.

  3. Three dimensional maximally supersymmetric field theory revisited

    International Nuclear Information System (INIS)

    The field theoretical realization of maximally extended supersymmetry algebra in 3 dimensions is revisited here. The existence of an interacting field theory which also manifests the full automorphism demands the existence of extra global symmetry transformations. They form the infinite-dimensional group of volume-preserving diffeomorphisms of an internal 3-dimensional space. Upon regularization, it will be truncated to a finite-dimensional unitary group. This extra symmetry together with multiplicity of component fields allow one to consistently introduce self-interactions through Nambu brackets or matrix 4-commutators. It turns out that there exists a conformal field theory which is invariant under OSp(4 | 8) x U(N) groups of global transformations. Relaxing full automorphism to its biggest subgroup, one can consistently mass-deforms the theory. In addition to ordinary associative algebraic structures, a non-associative structure also underlies this theory. (author)

  4. Revisiting instanton corrections to the Konishi multiplet

    CERN Document Server

    Alday, Luis F

    2016-01-01

    We revisit the calculation of instanton effects in correlation functions in ${\\cal N}=4$ SYM involving the Konishi operator and operators of twist two. Previous studies revealed that the scaling dimensions and the OPE coefficients of these operators do not receive instanton corrections in the semiclassical approximation. We go beyond this approximation and demonstrate that, while operators belonging to the same ${\\cal N}=4$ supermultiplet ought to have the same conformal data, the evaluation of quantum instanton corrections for one operator can be mapped into a semiclassical computation for another operator in the same supermultiplet. This observation allows us to compute explicitly the leading instanton correction to the scaling dimension of operators in the Konishi supermultiplet as well as to their structure constants in the OPE of two half-BPS scalar operators. We then use these results, together with crossing symmetry, to determine instanton corrections to scaling dimensions of twist-four operators with ...

  5. The Species Problem in Myxomycetes Revisited.

    Science.gov (United States)

    Walker, Laura M; Stephenson, Steven L

    2016-08-01

    Species identification in the myxomycetes (plasmodial slime molds or myxogastrids) poses particular challenges to researchers as a result of their morphological plasticity and frequent alteration between sexual and asexual life strategies. Traditionally, myxomycete morphology has been used as the primary method of species delimitation. However, with the increasing availability of genetic information, traditional myxomycete taxonomy is being increasingly challenged, and new hypotheses continue to emerge. Due to conflicts that sometimes occur between traditional and more modern species concepts that are based largely on molecular data, there is a pressing need to revisit the discussion surrounding the species concept used for myxomycetes. Biological diversity is being increasingly studied with molecular methods and data accumulates at ever-faster rates, making resolution of this matter urgent. In this review, currently used and potentially useful species concepts (biological, morphological, phylogenetic and ecological) are reviewed, and an integrated approach to resolve the myxomycete species problem is discussed. PMID:27351595

  6. Revisiting light neutralino scenarios in the MSSM

    CERN Document Server

    Vasquez, Daniel Albornoz; Boehm, Celine

    2011-01-01

    We revisit the case of a light neutralino LSP in the framework of the MSSM. We consider a model with eleven free parameters. We show that all scenarios where the annihilation of light neutralinos rely mainly on the exchange of a light pseudoscalar are excluded by direct detection searches and by Fermi measurements of the gamma-flux from dwarf spheroidal galaxies. On the other hand, we find scenarios with light sleptons that satisfy all collider and astroparticle physics constraints. In this case, the lower limit on the LSP mass is 12.6 GeV. We discuss how the parameter space of the model will be further probed by new physics searches at the LHC.

  7. Seasonal dating of Sappho's 'Midnight Poem' revisited

    Science.gov (United States)

    Cuntz, Manfred; Gurdemir, Levent; George, Martin

    2016-04-01

    Sappho was a Greek lyric poet who composed a significant array of pristine poetry. Although much of it has been lost, her reputation has endured thanks to numerous surviving fragments. One of her contributions includes the so-called 'Midnight Poem', which contains a line about the Pleiades, setting sometime before midnight, and supposedly observed from the island of Lesbos. This poem also refers to the setting of the Moon. Sappho's Midnight Poem thus represents a prime example of where ancient poetry and astronomy merge, and it also offers the possibility of seasonal dating. Previously, Herschberg and Mebius (1990) estimated that the poem was composed in late winter/early spring, a time frame that is not unusual for lyrics of an amorous nature. The aim of our paper is to revisit this earlier finding by using modern-day software. Our study confirms Herschberg and Mebius' result, but also conveys further information.

  8. Seeing the unseen: Charles Bonnet syndrome revisited.

    Science.gov (United States)

    Nair, Aditya Gopinathan; Nair, Akshay Gopinathan; Shah, Bharat R; Gandhi, Rashmin Anilkumar

    2015-09-01

    Charles Bonnet syndrome (CBS) is a rare condition that encompasses three clinical features: complex visual hallucinations, ocular pathology causing visual deterioration, and preserved cognitive status. Common associated ocular pathologies include age-related macular degeneration, glaucoma, and cataracts. Several theories have been proposed to try to explain the visual hallucinations. However, the pathophysiology remains poorly understood, and treatment is largely based on anecdotal data. The lack of awareness of CBS among medical professionals often leads to inappropriate diagnosis and medication. In a country like India, where awareness of mental health is not widespread, cultural myths and stigma prevent patients from seeking professional help. Here we describe two cases of CBS and revisit different ocular morbidities that have been reported to occur in conjunction with CBS. Psychiatrists and ophthalmologists alike must be sensitive to this clinical condition to ensure prompt diagnosis and treatment.

  9. Revisiting Lepton Flavour Universality in B Decays

    CERN Document Server

    Feruglio, Ferruccio; Pattori, Andrea

    2016-01-01

    Lepton flavour universality (LFU) in B-decays is revisited in a model-independent way by considering semileptonic operators defined at a scale Lambda above the electroweak scale v. The importance of quantum effects, so far neglected in the literature, is emphasised. We construct the low-energy effective Lagrangian taking into account the running effects from Lambda down to v through the one-loop renormalization group equations (RGE) in the limit of exact electroweak symmetry and QED RGEs from v down to the 1 GeV scale. The most important quantum effects turn out to be the modification of the leptonic couplings of the vector boson Z and the generation of a purely leptonic effective Lagrangian. Large LFU breaking effects in Z and tau decays and visible lepton flavour violating (LFV) effects in the processes tau -> mu ll, tau -> mu rho, tau -> mu pi and tau -> mu eta^(') are induced.

  10. The Faraday effect revisited: General theory

    DEFF Research Database (Denmark)

    Cornean, Horia Decebal; Nenciu, Gheorghe; Pedersen, Thomas Garm

    conductivity can be explicitly computed and coincides with the classical result. In the general case, using magnetic perturbation theory, the conductivity tensor is expanded in powers of the strength of the magnetic field B. Then the linear term in B of this expansion is written down in terms of the zero......This paper is the first in a series revisiting the Faraday effect, or more generally, the theory of electronic quantum transport/optical response in bulk media in the presence of a constant magnetic field. The independent electron approximation is assumed. For free electrons, the transverse...... magnetic field Green function and the zero field current operator. In the periodic case, the linear term in B of the conductivity tensor is expressed in terms of zero magnetic field Bloch functions and energies. No derivatives with respect to the quasimomentum appear and thereby all ambiguities are removed...

  11. (η6-Benzene(carbonato-κ2O,O′[dicyclohexyl(naphthalen-1-ylmethylphosphane-κP]ruthenium(II chloroform trisolvate

    Directory of Open Access Journals (Sweden)

    Saravanan Gowrisankar

    2014-07-01

    Full Text Available The title compound, [Ru(CO3(η6-C6H6{(C6H112P(CH2C10H7}]·3CHCl3, was synthesized by carbonation of [RuCl2(η6-C6H6{(C6H112P(CH2C10H7}] with NaHCO3 in methanol at room temperature. The RuII atom is surrounded by a benzene ligand, a chelating carbonate group and a phosphane ligand in a piano-stool configuration. The crystal packing is consolidated by C—H...O and C—H...Cl hydrogen-bonding interactions between adjacent metal complexes and between the complexes and the solvent molecules. The asymmetric unit contains one metal complex and three chloroform solvent molecules of which only one was modelled. The estimated diffraction contributions of the other two strongly disordered chloroform solvent molecules were substracted from the observed diffraction data using the SQUEEZE procedure in PLATON [Spek (2009. Acta Cryst. D65, 148–155].

  12. The global atmospheric budget of ethanol revisited

    Directory of Open Access Journals (Sweden)

    W. V. Kirstine

    2012-01-01

    Full Text Available Ethanol is an important biogenic volatile organic compound, which is increasingly used as a fuel for motor vehicles; therefore, an improved understanding of its atmospheric cycle is important. In this paper we use three sets of observational data, measured emissions of ethanol from living plants, measured concentrations of ethanol in the atmosphere and measured hydroxyl concentrations in the atmosphere (by methyl chloroform titration, to make two independent estimates related to the rate of cycling of ethanol through the atmosphere. In the first estimate, simple calculations give the emission rate of ethanol from living plants as 26 (range, 10–38 Tg yr−1. This contributes significantly to the total global ethanol source of 42 (range, 25–56 Tg yr−1. In the second estimate, the total losses of ethanol from the global atmosphere are 70 (range, 50–90 Tg yr−1, with about three-quarters of the ethanol removed by reaction with hydroxyl radicals in the gaseous and aqueous phases of the atmosphere, and the remainder lost through wet and dry deposition to land. These values of both the source of ethanol from living plants and the removal of atmospheric ethanol via oxidation by hydroxyl radicals (derived entirely from observations are significantly larger than those in recent literature. We suggest that a revision of the estimate of global ethanol emissions from plants to the atmosphere to a value comparable with this analysis is warranted.

  13. Dithizone chloroform single drop microextraction system combined with electrothermal atomic absorption spectrometry using Ir as permanent modifier for the determination of Cd in water and biological samples

    Science.gov (United States)

    Fan, Zhefeng; Zhou, Wei

    2006-07-01

    A simple and sensitive method using dithizone-chloroform single drop microextraction has been developed for separation and preconcentration of trace Cd prior to its determination by electrothermal atomic absorption spectrometry with Ir as permanent modifier. Parameters, such as pyrolysis and atomization temperature, solvent type, pH, dithizone concentration, extraction time, organic drop volume, stirring rate and sample volume were investigated. Under the optimized conditions, a detection limit (3 σ) of 0.7 ng/l and enrichment factor of 65 were achieved. The relative standard deviation was 7.4% ( c = 0.2 μg/l, n = 5). The developed method has been applied to the determination of trace Cd in water samples and biological reference materials with satisfactory results.

  14. Dithizone-chloroform single drop microextraction system combined with electrothermal atomic absorption spectrometry using Ir as permanent modifier for the determination of Cd in water and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Fan Zhefeng [Department of Chemistry, Shanxi Normal University, Linfen 041004 (China)]. E-mail: zhefengfan@163.com; Zhou Wei [Department of Chemistry, Shanxi Normal University, Linfen 041004 (China)

    2006-07-15

    A simple and sensitive method using dithizone-chloroform single drop microextraction has been developed for separation and preconcentration of trace Cd prior to its determination by electrothermal atomic absorption spectrometry with Ir as permanent modifier. Parameters, such as pyrolysis and atomization temperature, solvent type, pH, dithizone concentration, extraction time, organic drop volume, stirring rate and sample volume were investigated. Under the optimized conditions, a detection limit (3{sigma}) of 0.7 ng/l and enrichment factor of 65 were achieved. The relative standard deviation was 7.4% (c = 0.2 {mu}g/l, n = 5). The developed method has been applied to the determination of trace Cd in water samples and biological reference materials with satisfactory results.

  15. Sperm motility inhibitory effect of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkey, Presbytis entellus entellus

    Institute of Scientific and Technical Information of China (English)

    Nirmal K.Lohiya; Boomi Manivannan; Shipra Goyal; Abdul S.Ansari

    2008-01-01

    Aim: To assess the contraceptive efficacy of the benzene chromatographic fraction of the chloroform extract of the seeds of Carica papaya in langur monkeys. Methods: The test substance was given p.o. to five monkeys at 50 mg/kg body weight/day for 360 days. Control animals (n = 3) received olive oil as vehicle. Sperm parameters as per World Health Organization standards, sperm functional tests, morphology of testis and epididymis, haematology, clinical biochemistry, serum testosterone and libido were evaluated. Following completion of 360 days treatment the animals were withdrawn from the treatment and the recovery pattern was assessed by semen analysis and sperm functional tests. Results: Total inhibition of sperm motility was observed following 60 days of treatment that continued until 360 days study period. Sperm count, percent viability and percent normal spermatozoa showed a drastic decline following 30 days of treatment. Sperm morphology showed predominant mid piece abnormalities. Sperm functional tests scored in sterile range. Histology and ultrastructure of testis revealed vacuolization in the Sertoli cells and germ cells. Loss of cytoplasmic organelles was evident in spermatocytes and round spermatids. Histology and ultrastruc-ture of epididymis of treated animals were comparable to those of control animals. Hematological and serum clinicalparameters and testosterone levels fluctuated within the control range throughout the study period. Recovery was evident following 60-120 days of treatment withdrawal. Conclusion: The results suggest that the benzene chro-matographic fraction of the chloroform extract of the seeds of Carica papaya shows contraceptive efficacy without adverse toxicity, mediated through inhibition of sperm motility.

  16. Scaling Relationships for Spherical Polymer Brushes Revisited.

    Science.gov (United States)

    Chen, Guang; Li, Hao; Das, Siddhartha

    2016-06-16

    In this short paper, we revisit the scaling relationships for spherical polymer brushes (SPBs), i.e., polymer brushes grafted to rigid, spherical particles. Considering that the brushes can be described to be encased in a series of hypothetical spherical blobs, we identify significant physical discrepancies in the model of Daoud and Cotton (Journal of Physics, 1982), which is considered to be the state of the art in scaling modeling of SPBs. We establish that the "brush" configuration of the polymer molecules forming the SPBs is possible only if the swelling ratio (which is the ratio of the end-to-end length of the blob-encased polymer segment to the corresponding coil-like polymer segment) is always less than unity-a notion that has been erroneously overlooked in the model of Daoud and Cotton. We also provide new scaling arguments that (a) establish this swelling (or more appropriately shrinking) ratio as a constant (less than unity) for the case of "good" solvent, (b) recover the scaling predictions for blob dimension and monomer number and monomer concentration distributions within the blob, and

  17. Charge symmetry breaking in $\\Lambda$ hypernuclei revisited

    CERN Document Server

    Gal, Avraham

    2015-01-01

    The large charge symmetry breaking (CSB) implied by the $\\Lambda$ binding energy difference $\\Delta B^{4}_{\\Lambda}(0^+_{\\rm g.s.})\\equiv B_{\\Lambda}(_{\\Lambda}^4$He)$-$$B_{\\Lambda}(_{\\Lambda}^4$H) = 0.35$\\pm$0.06 MeV of the $A=4$ mirror hypernuclei ground states, determined from emulsion studies, has defied theoretical attempts to reproduce it in terms of CSB in hyperon masses and in hyperon-nucleon interactions, including one pion exchange arising from $\\Lambda-\\Sigma^0$ mixing. Using a schematic strong-interaction $\\Lambda N\\leftrightarrow\\Sigma N$ coupling model developed by Akaishi and collaborators for $s$-shell $\\Lambda$ hypernuclei, we revisit the evaluation of CSB in the $A=4$ $\\Lambda$ hypernuclei and extend it to $p$-shell mirror $\\Lambda$ hypernuclei. The model yields values of $\\Delta B^{4}_{\\Lambda} (0^+_{\\rm g.s.})\\sim 0.25$ MeV. Smaller size and mostly negative $p$-shell binding energy differences are calculated for the $A=7-10$ mirror hypernuclei, in rough agreement with the few available dat...

  18. Targeting Cancer Metabolism - Revisiting the Warburg Effects.

    Science.gov (United States)

    Tran, Quangdon; Lee, Hyunji; Park, Jisoo; Kim, Seon-Hwan; Park, Jongsun

    2016-07-01

    After more than half of century since the Warburg effect was described, this atypical metabolism has been standing true for almost every type of cancer, exhibiting higher glycolysis and lactate metabolism and defective mitochondrial ATP production. This phenomenon had attracted many scientists to the problem of elucidating the mechanism of, and reason for, this effect. Several models based on oncogenic studies have been proposed, such as the accumulation of mitochondrial gene mutations, the switch from oxidative phosphorylation respiration to glycolysis, the enhancement of lactate metabolism, and the alteration of glycolytic genes. Whether the Warburg phenomenon is the consequence of genetic dysregulation in cancer or the cause of cancer remains unknown. Moreover, the exact reasons and physiological values of this peculiar metabolism in cancer remain unclear. Although there are some pharmacological compounds, such as 2-deoxy-D-glucose, dichloroacetic acid, and 3-bromopyruvate, therapeutic strategies, including diet, have been developed based on targeting the Warburg effect. In this review, we will revisit the Warburg effect to determine how much scientists currently understand about this phenomenon and how we can treat the cancer based on targeting metabolism. PMID:27437085

  19. The drive revisited: Mastery and satisfaction.

    Science.gov (United States)

    Denis, Paul

    2016-06-01

    Starting from the theory of the libido and the notions of the experience of satisfaction and the drive for mastery introduced by Freud, the author revisits the notion of the drive by proposing the following model: the drive takes shape in the combination of two currents of libidinal cathexis, one which takes the paths of the 'apparatus for obtaining mastery' (the sense-organs, motricity, etc.) and strives to appropriate the object, and the other which cathects the erotogenic zones and the experience of satisfaction that is experienced through stimulation in contact with the object. The result of this combination of cathexes constitutes a 'representation', the subsequent evocation of which makes it possible to tolerate for a certain period of time the absence of a satisfying object. On the basis of this conception, the author distinguishes the representations proper, vehicles of satisfaction, from imagos and traumatic images which give rise to excitation that does not link up with the paths taken by the drives. This model makes it possible to conciliate the points of view of the advocates of 'object-seeking' and of those who give precedence to the search for pleasure, and, further, to renew our understanding of object-relations, which can then be approached from the angle of their relations to infantile sexuality. Destructiveness is considered in terms of "mastery madness" and not in terms of the late Freudian hypothesis of the death drive.

  20. Revisiting the argument from fetal potential

    Directory of Open Access Journals (Sweden)

    Manninen Bertha

    2007-05-01

    Full Text Available Abstract One of the most famous, and most derided, arguments against the morality of abortion is the argument from potential, which maintains that the fetus' potential to become a person and enjoy the valuable life common to persons, entails that its destruction is prima facie morally impermissible. In this paper, I will revisit and offer a defense of the argument from potential. First, I will criticize the classical arguments proffered against the importance of fetal potential, specifically the arguments put forth by philosophers Peter Singer and David Boonin, by carefully unpacking the claims made in these arguments and illustrating why they are flawed. Secondly, I will maintain that fetal potential is morally relevant when it comes to the morality of abortion, but that it must be accorded a proper place in the argument. This proper place, however, cannot be found until we first answer a very important and complex question: we must first address the issue of personal identity, and when the fetus becomes the type of being who is relevantly identical to a future person. I will illustrate why the question of fetal potential can only be meaningfully addressed after we have first answered the question of personal identity and how it relates to the human fetus.

  1. Revisiting the relaxation dynamics of isolated pyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Montero, Raúl; Ovejas, Virginia; Fernández-Fernández, Marta; Longarte, Asier, E-mail: asier.longarte@ehu.es [Departamento de Química Física, Universidad del País Vasco (UPV/EHU), Apart. 644, 48080 Bilbao (Spain); Peralta Conde, Álvaro [Centro de Láseres Pulsados (CLPU), Edificio M3, Parque Científico, 37185 Villamayor (Spain)

    2014-07-07

    Herein, the interpretation of the femtosecond-scale temporal evolution of the pyrrole ion signal, after excitation in the 267–217 nm interval, recently published by our group [R. Montero, A. Peralta Conde, V. Ovejas, M. Fernández-Fernández, F. Castaño, J. R. Vázquez de Aldana, and A. Longarte, J. Chem. Phys.137, 064317 (2012)] is re-visited. The observation of a shift in the pyrrole{sup +} transient respect to zero delay reference, initially attributed to ultrafast dynamics on the πσ{sup *} type state (3s a{sub 1} ← π 1a{sub 2}), is demonstrated to be caused by the existence of pump + probe populated states, along the ionization process. The influence of these resonances in pump-prone ionization experiments, when multi-photon probes are used, and the significance of a proper zero-time reference, is discussed. The possibility of preparing the πσ{sup *} state by direct excitation is investigated by collecting 1 + 1 photoelectron spectra, at excitation wavelengths ranging from 255 to 219 nm. No conclusive evidences of ionization through this state are found.

  2. Targeting Cancer Metabolism - Revisiting the Warburg Effects

    Science.gov (United States)

    Tran, Quangdon; Lee, Hyunji; Park, Jisoo; Kim, Seon-Hwan; Park, Jongsun

    2016-01-01

    After more than half of century since the Warburg effect was described, this atypical metabolism has been standing true for almost every type of cancer, exhibiting higher glycolysis and lactate metabolism and defective mitochondrial ATP production. This phenomenon had attracted many scientists to the problem of elucidating the mechanism of, and reason for, this effect. Several models based on oncogenic studies have been proposed, such as the accumulation of mitochondrial gene mutations, the switch from oxidative phosphorylation respiration to glycolysis, the enhancement of lactate metabolism, and the alteration of glycolytic genes. Whether the Warburg phenomenon is the consequence of genetic dysregulation in cancer or the cause of cancer remains unknown. Moreover, the exact reasons and physiological values of this peculiar metabolism in cancer remain unclear. Although there are some pharmacological compounds, such as 2-deoxy-D-glucose, dichloroacetic acid, and 3-bromopyruvate, therapeutic strategies, including diet, have been developed based on targeting the Warburg effect. In this review, we will revisit the Warburg effect to determine how much scientists currently understand about this phenomenon and how we can treat the cancer based on targeting metabolism. PMID:27437085

  3. [What mirror neurons have revealed: revisited].

    Science.gov (United States)

    Murata, Akira; Maeda, Kazutaka

    2014-06-01

    The first paper on mirror neurons was published in 1992. In the span of over two decades since then, much knowledge about the relationship between social cognitive function and the motor control system has been accumulated. Direct matching of visual actions and their corresponding motor representations is the most important functional property of mirror neuron. Many studies have emphasized intrinsic simulation as a core concept for mirror neurons. Mirror neurons are thought to play a role in social cognitive function. However, the function of mirror neurons in the macaque remains unclear, because such cognitive functions are limited or lacking in macaque monkeys. It is therefore important to discuss these neurons in the context of motor function. Rizzolatti and colleagues have stressed that the most important function of mirror neurons in macaques is recognition of actions performed by other individuals. I suggest that mirror neurons in the Macaque inferior pariental lobule might be correlated with body schema. In the parieto-premotor network, matching of corollary discharge and actual sensory feedback is an essential neuronal operation. Recently, neurons showing mirror properties were found in some cortical areas outside the mirror neuron system. The current work would revisit the outcomes of mirror neuron studies to discuss the function of mirror neurons in the monkey.

  4. Revisiting Twomey's approximation for peak supersaturation

    Directory of Open Access Journals (Sweden)

    B. J. Shipway

    2014-10-01

    Full Text Available Twomey's seminal 1959 paper provided lower and upper bound approximations to the estimation of peak supersaturation within an updraft and thus provides the first closed expression for the number of nucleated cloud droplets. The form of this approximation is simple, but provides a surprisingly good estimate and has subsequently been employed in more sophisticated treatments of nucleation parametrization. In the current paper, we revisit the lower bound approximation of Twomey and make a small adjustment which can be used to obtain a more accurate calculation of peak supersaturation under all potential aerosol loadings and thermodynamic conditions. In order to make full use of this improved approximation, the underlying integro-differential equation for supersaturation evolution and the condition for calculating peak supersaturation are examined. A simple rearrangement of the algebra allows for an expression to be written down which can then be solved with a single lookup table with only one independent variable for an underlying lognormal aerosol population. Multimode aerosol with only N different dispersion characteristics require only N of these one-dimensional lookup tables. No additional information is required in the lookup table to deal with additional chemical, physical or thermodynamic properties. The resulting implementation provides a relatively simple, yet computationally cheap and very accurate physically-based parametrization of droplet nucleation for use in climate and NWP models.

  5. The Super-GUT CMSSM Revisited

    CERN Document Server

    Ellis, John; Mustafayev, Azar; Nagata, Natsumi; Olive, Keith A

    2016-01-01

    We revisit minimal supersymmetric SU(5) grand unification (GUT) models in which the soft supersymmetry-breaking parameters of the minimal supersymmetric Standard Model (MSSM) are universal at some input scale, $M_{in}$, above the supersymmetric gauge coupling unification scale, $M_{GUT}$. As in the constrained MSSM (CMSSM), we assume that the scalar masses and gaugino masses have common values, $m_0$ and $m_{1/2}$ respectively, at $M_{in}$, as do the trilinear soft supersymmetry-breaking parameters $A_0$. Going beyond previous studies of such a super-GUT CMSSM scenario, we explore the constraints imposed by the lower limit on the proton lifetime and the LHC measurement of the Higgs mass, $m_h$. We find regions of $m_0$, $m_{1/2}$, $A_0$ and the parameters of the SU(5) superpotential that are compatible with these and other phenomenological constraints such as the density of cold dark matter, which we assume to be provided by the lightest neutralino. Typically, these allowed regions appear for $m_0$ and $m_{1/...

  6. Spin-orbit evolution of Mercury revisited

    CERN Document Server

    Noyelles, Benoit; Makarov, Valeri; Efroimsky, Michael

    2013-01-01

    Mercury is a peculiar case, in that it is locked into the 3:2 spin-orbit resonance. Its rotation period, 58 days, is exactly two thirds of its orbital period. It is accepted that the eccentricity of Mercury (0.206) favours the trapping into this resonance. More controversial is how the capture took place. A recent study by Makarov has shown that entrapment into this resonance is certain if the eccentricity is larger than 0.2, provided that we use a realistic tidal model, based on the Darwin-Kaula expansion of the tidal torque, including both the elastic rebound and anelastic creep of solids. We here revisit the scenario of Mercury's capture into the supersynchronous spin-orbit resonances. The study is based on a realistic model of tidal friction in solids, that takes into account the rheology and the self-gravitation of the planet. Developed in Efroimsky, it was employed by Makarov et al. to determine the likely spin state of the planet GJ581d, with its eccentricity evolution taken into account. It was also u...

  7. No-scale ripple inflation revisited

    International Nuclear Information System (INIS)

    We revisit the no-scale ripple inflation model, where no-scale supergravity is modified by an additional term for the inflaton field in the Kähler potential. This term not only breaks one SU(N,1) symmetry explicitly, but also plays an important role for inflation. We generalize the superpotential in the no-scale ripple inflation model slightly. There exists a discrete Z2 symmetry/parity in the scalar potential in general, which can be preserved or violated by the non-canonical nomalized inflaton kinetic term. Thus, there are three inflation paths: one parity invariant path, and the left and right paths for parity violating scenario. We show that the inflations along the parity invariant path and right path are consistent with the Planck results. However, the gavitino mass for the parity invariant path is so large that the inflation results will be invalid if we consider the inflaton supersymmetry breaking soft mass term. Thus, only the inflation along the right path gives the correct and consistent results. Notably, the tensor-to-scalar ratio in such case can be large, with a value around 0.05, which may be probed by the future Planck experiment

  8. Searle's"Dualism Revisited"

    Energy Technology Data Exchange (ETDEWEB)

    P., Henry

    2008-11-20

    A recent article in which John Searle claims to refute dualism is examined from a scientific perspective. John Searle begins his recent article 'Dualism Revisited' by stating his belief that the philosophical problem of consciousness has a scientific solution. He then claims to refute dualism. It is therefore appropriate to examine his arguments against dualism from a scientific perspective. Scientific physical theories contain two kinds of descriptions: (1) Descriptions of our empirical findings, expressed in an every-day language that allows us communicate to each other our sensory experiences pertaining to what we have done and what we have learned; and (2) Descriptions of a theoretical model, expressed in a mathematical language that allows us to communicate to each other certain ideas that exist in our mathematical imaginations, and that are believed to represent, within our streams of consciousness, certain aspects of reality that we deem to exist independently of their being perceived by any human observer. These two parts of our scientific description correspond to the two aspects of our general contemporary dualistic understanding of the total reality in which we are imbedded, namely the empirical-mental aspect and the theoretical-physical aspect. The duality question is whether this general dualistic understanding of ourselves should be regarded as false in some important philosophical or scientific sense.

  9. Revisiting the Anatomy of the Living Heart.

    Science.gov (United States)

    Mori, Shumpei; Spicer, Diane E; Anderson, Robert H

    2016-01-01

    An understanding of the complexity of cardiac anatomy is required by all who seek, in the setting of cardiac disease, to interpret the images confronting them. Although the mysteries of cardiac structure have been extensively addressed, significant gaps continue to exist between the descriptions provided by morphologists and by those working in the clinical setting. In part, this reflects the limitations in providing 3D visualization of such a complicated organ. Current 3D imaging technology now permits visualization of the cardiac components using datasets obtained in the living individual. These advances, furthermore, demonstrate the anatomy in the setting of the heart as imaged within the thorax. It has been failure to describe the heart as it lies within the thorax that remains a major deficiency of many morphologists relying on the dissecting room to provide the gold standard. Describing the heart in attitudinally appropriate fashion, a basic rule of clinical anatomy, creates the necessary bridges between anatomists and clinicians. The rapid progression of cardiac interventional techniques, furthermore, emphasizes the need to revisit cardiac anatomy using a multidisciplinary approach. In this review, therefore, we illustrate the advantages of an attitudinally correct approach to cardiac anatomy. We then focus on the morphology of the arterial roots, revealing the accuracy that can now be achieved by clinicians using datasets obtained during life.

  10. Pair Production Constraints on Superluminal Neutrinos Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Brodsky, Stanley J.; /SLAC; Gardner, Susan; /Kentucky U.

    2012-02-16

    We revisit the pair creation constraint on superluminal neutrinos considered by Cohen and Glashow in order to clarify which types of superluminal models are constrained. We show that a model in which the superluminal neutrino is effectively light-like can evade the Cohen-Glashow constraint. In summary, any model for which the CG pair production process operates is excluded because such timelike neutrinos would not be detected by OPERA or other experiments. However, a superluminal neutrino which is effectively lightlike with fixed p{sup 2} can evade the Cohen-Glashow constraint because of energy-momentum conservation. The coincidence involved in explaining the SN1987A constraint certainly makes such a picture improbable - but it is still intrinsically possible. The lightlike model is appealing in that it does not violate Lorentz symmetry in particle interactions, although one would expect Hughes-Drever tests to turn up a violation eventually. Other evasions of the CG constraints are also possible; perhaps, e.g., the neutrino takes a 'short cut' through extra dimensions or suffers anomalous acceleration in matter. Irrespective of the OPERA result, Lorentz-violating interactions remain possible, and ongoing experimental investigation of such possibilities should continue.

  11. The Importance of Being a Complement: CED Effects Revisited

    Science.gov (United States)

    Jurka, Johannes

    2010-01-01

    This dissertation revisits subject island effects (Ross 1967, Chomsky 1973) cross-linguistically. Controlled acceptability judgment studies in German, English, Japanese and Serbian show that extraction out of specifiers is consistently degraded compared to extraction out of complements, indicating that the Condition on Extraction domains (CED,…

  12. Intramolecular Amide Hydrolysis in N-Methylmaleamic Acid Revisited

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The intramolecular amide hydrolysis of N-methylmaleamic acid have been revisited by use of density functional theory and inclusion of solvent effects. The results indicate that concerted reaction mechanism is favored over stepwise reaction mechanism. This is in agreement with the previous theoretical study. Sovlent effects have significant influence on the reaction barrier.

  13. Educational Administration and the Management of Knowledge: 1980 Revisited

    Science.gov (United States)

    Bates, Richard

    2013-01-01

    This paper revisits the thesis of a 1980 paper that suggested a new approach to educational administration based upon the New Sociology of Education. In particular it updates answers to the six key questions asked by that paper: what counts as knowledge; how is what counts as knowledge organised; how is what counts as knowledge transmitted; how is…

  14. The Polarized Structure Function $g_{2} A Lattice Study Revisited

    CERN Document Server

    Göckeler, M; Kürzinger, W; Oelrich, H; Rakow, P; Schierholz, G

    1999-01-01

    A recent lattice calculation of the spin-dependent structure function g_2 is revisited. It has been recognized that the twist-three operator, which gives rise to d_2, mixes non-perturbatively with operators of lower dimensions under renormalization. This changes the results substantially.

  15. "An analysis of the classical Doppler Effect"[1] revisited

    OpenAIRE

    Rothenstein, Bernhard; Nafornita, Corina

    2004-01-01

    After having shown that the formula which describes the Doppler effect in the general case holds only in the case of the "very high" frequency assumption, we derive free of assumptions Doppler formulas for two scenarios presented in the revisited paper.

  16. Revisiting Mental Simulation in Language Comprehension: Six Replication Attempts

    NARCIS (Netherlands)

    R.A. Zwaan (Rolf); D. Pecher (Diane)

    2012-01-01

    textabstractThe notion of language comprehension as mental simulation has become popular in cognitive science. We revisit some of the original empirical evidence for this. Specifically, we attempted to replicate the findings from earlier studies that examined the mental simulation of object orientat

  17. Complex and detailed balancing of chemical reaction networks revisited

    NARCIS (Netherlands)

    van der Schaft, Abraham; Rao, Shodhan; Jayawardhana, Bayu

    2015-01-01

    The characterization of the notions of complex and detailed balancing for mass action kinetics chemical reaction networks is revisited from the perspective of algebraic graph theory, in particular Kirchhoff’s Matrix Tree theorem for directed weighted graphs. This yields an elucidation of previously

  18. Coccolithophores in Polar Waters: Papposphaera arctica HET and HOL revisited

    DEFF Research Database (Denmark)

    Thomsen, Helge Abildhauge; Heldal, Mikal; Østergaard, Jette B.

    2016-01-01

    It has been generally accepted based on the finding of combination coccospheres in field samples that Turrisphaera arctica and Papposphaera sarion are alternate life-cycle phases of a single species. However, while recently revisiting P. sarion it became evident that the Turrisphaera phase of thi...

  19. Closing Achievement Gaps: Revisiting Benjamin S. Bloom's "Learning for Mastery"

    Science.gov (United States)

    Guskey, Thomas R.

    2007-01-01

    The problem of achievement gaps among different subgroups of students has been evident in education for many years. This manuscript revisits the work of renowned educator Benjamin S. Bloom, who saw reducing gaps in the achievement of various groups of students as a simple problem of reducing variation in student learning outcomes. Bloom observed…

  20. A control center design revisited: learning from users’ appropriation

    DEFF Research Database (Denmark)

    Souza da Conceição, Carolina; Cordeiro, Cláudia

    2014-01-01

    This paper aims to present the lessons learned during a control center design project by revisiting another control center from the same company designed two and a half years before by the same project team. In light of the experience with the first project and its analysis, the designers and res...

  1. Bohr’s ‘Light and Life’ revisited

    Science.gov (United States)

    Nussenzveig, H. M.

    2015-11-01

    I revisit Niels Bohr’s famous 1932 ‘Light and Life’ lecture, confronting it with current knowledge. Topics covered include: life origin and evolution, quantum mechanics and life, brain and mind, consciousness and free will, and light as a tool for biology, with special emphasis on optical tweezers and their contributions to biophysics. Specialized knowledge of biology is not assumed.

  2. Dynamics of Shape Fluctuations of Quasi-spherical Vesicles Revisited

    DEFF Research Database (Denmark)

    Miao, L.; Lomholt, Michael Andersen; Kleis, J.

    2002-01-01

    In this paper, the dynamics of spontaneous shape fluctuations of a single, giant quasi-spherical vesicle formed from a single lipid species is revisited theoretically. A coherent physical theory for the dynamics is developed based on a number of fundamental principles and considerations, and a sy...

  3. Additively homomorphic encryption with a double decryption mechanism, revisited

    NARCIS (Netherlands)

    Peter, A.; Kronberg, M.; Trei, W.; Katzenbeisser, S.

    2012-01-01

    We revisit the notion of additively homomorphic encryption with a double decryption mechanism (DD-PKE), which allows for additions in the encrypted domain while having a master decryption procedure that can decrypt all properly formed ciphertexts by using a special master secret. This type of encryp

  4. Revisiting the Role of Organizational Effectiveness in Educational Evaluation.

    Science.gov (United States)

    Lotto, Linda S.

    Organizational effectiveness ought to play a role in educational evaluation, and the development of alternative perspectives for viewing organizations could be a starting point for revisiting organizational evaluation in education. Five possible perspectives and criteria for evaluating organizations have been developed. If an organization is…

  5. Keep Moving! Revisiting Thumbnails for Mobile Video Retrieval

    NARCIS (Netherlands)

    W. Hürst; C.G.M. Snoek; W.J. Spoel; M. Tomin

    2010-01-01

    Motivated by the increasing popularity of video on handheld devices and the resulting importance for effective video retrieval, this paper revisits the relevance of thumbnails in a mobile video retrieval setting. Our study indicates that users are quite able to handle and assess small thumbnails on

  6. Backwardation in energy futures markets: Metalgesellschaft revisited

    International Nuclear Information System (INIS)

    Energy supply contracts negotiated by the US Subsidiary of Metalgesellschaft Refining and Marketing (MGRM), which were the subject of much subsequent debate, are re-examined. The contracts were hedged by the US Subsidiary barrel-for-barrel using short-dated energy derivatives. When the hedge program experienced difficulties, the derivatives positions were promptly liquidated by the parent company. Revisiting the MGRM contracts also provides the opportunity to explore the latest evidence on backwardation in energy markets. Accordingly, the paper discusses first the theoretical reasons for backwardation, followed by an empirical examination using the MGRM data available at the time of the hedge program in 1992 and a second set of data that became available in 2000. By using a more up-to-date data set covering a longer time period and by controlling the time series properties of the data, the authors expect to provide more reliable empirical evidence on the behaviour of energy futures prices. Results based on the 1992 data suggest that the strategy employed by MGRM could be expected to be profitable while the risks are relatively low. However, analysis based on the 2000 data shows lower, although still significant profits, but higher risks. The final conclusion was that the likelihood of problems similar to those faced by MGRM in 1992 are twice as high with the updated 2000 data, suggesting that the risk-return pattern of the stack-and-roll hedging strategy using short-dated energy future contracts to hedge long-tem contracts is less appealing now than when MGRM implemented its hedging program in 1992. 24 refs., 3 tabs., 6 figs

  7. Distributions and sea-to-air fluxes of chloroform, trichloroethylene, tetrachloroethylene, chlorodibromomethane and bromoform in the Yellow Sea and the East China Sea during spring.

    Science.gov (United States)

    He, Zhen; Yang, Gui-Peng; Lu, Xiao-Lan; Zhang, Hong-Hai

    2013-06-01

    Halocarbons including chloroform (CHCl3), trichloroethylene (C2HCl3), tetrachloroethylene (C2Cl4), chlorodibromomethane (CHBr2Cl) and bromoform (CHBr3) were measured in the Yellow Sea (YS) and the East China Sea (ECS) during spring 2011. The influences of chlorophyll a, salinity and nutrients on the distributions of these gases were examined. Elevated levels of these gases in the coastal waters were attributed to anthropogenic inputs and biological release by phytoplankton. The vertical distributions of these gases in the water column were controlled by different source strengths and water masses. Using atmospheric concentrations measured in spring 2012 and seawater concentrations obtained from this study, the sea-to-air fluxes of these gases were estimated. Our results showed that the emissions of C2HCl3, C2Cl4, CHBr2Cl, and CHBr3 from the study area could account for 16.5%, 10.5%, 14.6%, and 3.5% of global oceanic emissions, respectively, indicating that the coastal shelf may contribute significantly to the global oceanic emissions of these gases.

  8. A spectrophotometric and thermodynamic study of the charge-transfer complexes of iodine with 2-aminomethyl-15-crown-5 in chloroform and 1,2-dichloroethane solutions.

    Science.gov (United States)

    Hasani, Masoumeh; Akbari, Sakineh

    2007-05-01

    Interaction of 2-aminomethyl-15-crown-5 (AM15C5) with iodine has been investigated spectrophotometrically in chloroform and 1,2-dichloroethane (1,2-DCE) solutions. The observed time dependence of the charge-transfer band and subsequent formation of I(3)(-) in solution were related to the slow transformation of the initially formed 1:1 AM15C5.I(2) outer complex to an inner electron donor-acceptor (EDA) complex, followed by fast reaction of the inner complex with iodine to form a triiodide ion. The pseudo-first-order rate constants were evaluated from the absorbance- and conductivity-time data. The stoichiometry and formation constants of the resulting EDA complexes have also been determined. Thermodynamic parameters, Delta H degrees and Delta S degrees , of the complexes have been determined from the temperature dependence of stability constants by Van't Hoff equation. The results indicate that iodine complexes of AM15C5 in both solvents are enthalpy stabilized but entropy destabilized. The influence of solvent properties on the kinetics and stability of the resulting charge-transfer complexes are discussed.

  9. Optimization of a gas chromatography-mass spectrometry method with methyl chloroformate derivatization for quantification of amino acids in plant tissue.

    Science.gov (United States)

    Vancompernolle, Bram; Croes, Kim; Angenon, Geert

    2016-04-01

    Rapid, easy and reliable quantification of amino acids is crucial in research on plant amino acid metabolism and nutritional improvement of crops via enrichment of essential amino acids. A recently reported analysis method, based on solid phase extraction (SPE), derivatization with methyl chloroformate and gas chromatography-mass spectrometry was optimized and tested on three-week-old Arabidopsis thaliana leaf tissues. Optimization of the SPE cleanup yielded recovery rates of minimum 95% for all amino acids (except arginine). Variations in accuracy and precision did not exceed 12.5%, except for cysteine, histidine and tryptophane, which were excluded from analysis. Quantification of overlapping peaks for isoleucine/threonine and proline/asparagine was possible by selection of two specific fragment ions for each amino acid. Of the 16 selected amino acids, 14 were quantified successfully in at least 75% of the samples, while methionine and tyrosine were only quantifiable in 6% and 42%, respectively. A case study on the aspartate super pathway confirmed the applicability of the optimized method on wild type and genetically modified plants: external supplementation of methionine or lysine yielded a 146-fold or 27-fold increase in the respective absolute amino acid levels compared with the control treatment. Induced expression of dhdps-r1 (a mutated lysine biosynthesis gene encoding a feedback insensitive enzyme) caused an 83-fold increase in absolute lysine levels. PMID:26994331

  10. Cytotoxic Activities of Physalis minima L. Chloroform Extract on Human Lung Adenocarcinoma NCI-H23 Cell Lines by Induction of Apoptosis

    Directory of Open Access Journals (Sweden)

    Ooi Kheng Leong

    2011-01-01

    Full Text Available Physalis minima L. is reputed for having anticancer property. In this study, the chloroform extract of this plant exhibited remarkable cytotoxic activities on NCI-H23 (human lung adenocarcinoma cell line at dose- and time-dependent manners (after 24, 48 and 72 h of incubation. Analysis of cell-death mechanism demonstrated that the extract exerted apoptotic programed cell death in NCI-H23 cells with typical DNA fragmentation, which is a biochemical hallmark of apoptosis. Morphological observation using transmission electron microscope (TEM also displayed apoptotic characteristics in the treated cells, including clumping and margination of chromatins, followed by convolution of the nuclear and budding of the cells to produce membrane-bound apoptotic bodies. Different stages of apoptotic programed cell death as well as phosphatidylserine externalization were confirmed using annexin V and propidium iodide staining. Furthermore, acute exposure to the extract produced a significant regulation of c-myc, caspase-3 and p53 mRNA expression in this cell line. Due to its apoptotic effect on NCI-H23 cells, it is strongly suggested that the extract could be further developed as an anticancer drug.

  11. Amino acid analysis by reverse-phase high-performance liquid chromatography: improved derivatization and detection conditions with 9-fluorenylmethyl chloroformate.

    Science.gov (United States)

    Bank, R A; Jansen, E J; Beekman, B; te Koppele, J M

    1996-09-01

    An improved method for the quantitative derivatization of amino acids with fluorenylmethyl chloroformate (FMOC-Cl) is described. Amino acids are derivatized in borate buffer at pH 11.4 for 40 min at ambient temperature. All amino acids resulted in stable derivatives. In particular, improved derivatization was obtained with the troublesome amino acids His and Tyr: exclusively monosubstituted His and disubstituted Tyr were formed, eluting as free peaks in the chromatogram. These derivatives show a higher fluorescence response than their disubstituted and monosubstituted counterparts, respectively, resulting from other protocols. Under the new conditions, considerable less of the hydrolysis product of FMOC-Cl is seen in the chromatograms. Baseline noise was substantially reduced at a higher emission wavelength (630 nm instead of 313 or 340 nm). With simple precautions, extensive adsorption of the disubstituted derivatives (Lys, Hyl, and Tyr) on plastic or glass surfaces could be prevented. Calibration curves were linear over a 10 to 300 molar ratio of FMOC-Cl to total amino acid. The detection limits are in the femtomole range and the derivatives are stable for more than 48 h, thus permitting automated analysis of multiple samples. PMID:8811901

  12. Nuclear non-proliferation: Revisiting the basics

    International Nuclear Information System (INIS)

    The 1970 Treaty on the Non- Proliferation of Nuclear Weapons (NPT), with 188 States party, represents the cornerstone of the global nuclear non-proliferation and disarmament effort -- and despite recent challenges, it has never been more relevant than it is today. But if we are to move forward, it is essential to revisit a number of the basic assumptions and features of the existing regime, and consider a number of new approaches. A key assumption at the core of the NPT was that the asymmetry between nuclear-weapon States and non-nuclear-weapon States would gradually disappear. Progress has been made on the nuclear disarmament front, but much more remains to be done. Nuclear disarmament strategies have for the most part focused on the negotiation of bilateral nuclear arms control agreements between the holders of the two largest nuclear arsenals, and a few multilateral agreements designed to curb the quantitative and qualitative development of nuclear weapons. With the end of the Cold War as an impetus, some progress was made in the early and mid-1990s, but the process unfortunately slowed in the latter part of the decade. The discoveries of a clandestine nuclear weapon programme in Iraq after the 1991 Gulf War made it painfully clear that the IAEA verification system, with its focus on declared nuclear activities and its limited rights of access to information and sites, was not adequate for the IAEA to provide the comprehensive peaceful use assurances required under the NPT. This stark realization prompted the international community to significantly expand the IAEA's verification rights. These new rights were incorporated into a 1997 protocol additional to safeguards agreements, with a request for all States to subscribe to it. For the IAEA to provide the required assurances, it must have the required authority. It is clear that the success of the IAEA verification regime will depend heavily on achieving universal adherence to the required safeguards agreements

  13. The role of brand destination experience in determining revisit intention

    DEFF Research Database (Denmark)

    Mattsson, Jan; Barnes, Stuart; Sørensen, Flemming

    experience, which provides a more holistic and unified view of the brand destination. The research uses a logistic regression model to determine the role of satisfaction and brand experience in determining revisit intentions. The study also examines differences among subgroups and four brand experience sub......-constructs. The findings suggest that brand experience is an important determinant of revisit intentions, but that there is variation among respondent groups. The paper rounds off with conclusions and implications for research and practice.......Destination branding has developed considerably as a topic area in the last decade with numerous conceptualizations focusing on different aspects of the brand. However, a unified view has not yet emerged. This paper examines destination branding via a new conceptualization, brand destination...

  14. Enthalpy-Entropy Compensation (EEC) Effect: A Revisit.

    Science.gov (United States)

    Pan, Animesh; Biswas, Tapas; Rakshit, Animesh K; Moulik, Satya P

    2015-12-31

    A short account of the developments and perspectives of IKR (iso-kinetic relation) and EEC (enthalpy (H) - entropy (S) compensation) has been presented. The IKR and EEC are known to be extra thermodynamic or empirical correlations though linear H-S correlation can be thermodynamically deduced. Attempt has also been made to explain the phenomena in terms of statistical thermodynamics. In this study, we have briefly revisited the fundamentals of both IKR and EEC from kinetic and thermodynamic grounds. A detailed revisit of the EEC phenomenon on varied kinetic and equilibrium processes has been also presented. Possible correlations among the free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) changes of different similar and nonsimilar chemical processes under varied conditions have been discussed with possible future projections.

  15. The significance test controversy revisited the fiducial Bayesian alternative

    CERN Document Server

    Lecoutre, Bruno

    2014-01-01

    The purpose of this book is not only to revisit the “significance test controversy,”but also to provide a conceptually sounder alternative. As such, it presents a Bayesian framework for a new approach to analyzing and interpreting experimental data. It also prepares students and researchers for reporting on experimental results. Normative aspects: The main views of statistical tests are revisited and the philosophies of Fisher, Neyman-Pearson and Jeffrey are discussed in detail. Descriptive aspects: The misuses of Null Hypothesis Significance Tests are reconsidered in light of Jeffreys’ Bayesian conceptions concerning the role of statistical inference in experimental investigations. Prescriptive aspects: The current effect size and confidence interval reporting practices are presented and seriously questioned. Methodological aspects are carefully discussed and fiducial Bayesian methods are proposed as a more suitable alternative for reporting on experimental results. In closing, basic routine procedures...

  16. Discussion of "Computational Electrocardiography: Revisiting Holter ECG Monitoring".

    Science.gov (United States)

    Baumgartner, Christian; Caiani, Enrico G; Dickhaus, Hartmut; Kulikowski, Casimir A; Schiecke, Karin; van Bemmel, Jan H; Witte, Herbert

    2016-08-01

    This article is part of a For-Discussion-Section of Methods of Information in Medicine about the paper "Computational Electrocardiography: Revisiting Holter ECG Monitoring" written by Thomas M. Deserno and Nikolaus Marx. It is introduced by an editorial. This article contains the combined commentaries invited to independently comment on the paper of Deserno and Marx. In subsequent issues the discussion can continue through letters to the editor.

  17. Revisiting the Panko-Halverson Taxonomy of Spreadsheet Errors

    OpenAIRE

    Panko, Raymond R.

    2008-01-01

    The purpose of this paper is to revisit the Panko-Halverson taxonomy of spreadsheet errors and suggest revisions. There are several reasons for doing so: First, the taxonomy has been widely used. Therefore, it should have scrutiny; Second, the taxonomy has not been widely available in its original form and most users refer to secondary sources. Consequently, they often equate the taxonomy with the simplified extracts used in particular experiments or field studies; Third, perhaps as a consequ...

  18. China in 2005 Revisited: The Implications of International Capital Mobility

    OpenAIRE

    Ianchovichina, Elena; McDougall, Robert; Hertel, Thomas

    2000-01-01

    This paper revisits the analysis of the implications of China's economic growth on her trading partners presented in Arndt et al. (1997) using a dynamic, applied general equilibrium model that features international capital mobility. We find that accounting for the impact of China's growth on international capital markets reverses some of the findings in the paper by Arndt et al. In particular, net creditor regions lose while net debtor regions benefit from an economic slowdown in China du...

  19. Audit probability versus effectiveness: The Beckerian approach revisited

    OpenAIRE

    Rablen, M

    2014-01-01

    This is the accepted version of the following article: RABLEN, M. D. (2014), Audit Probability versus Effectiveness: The Beckerian Approach Revisited. Journal of Public Economic Theory, 16: 322–342, which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/jpet.12062/abstract. The Beckerian approach to tax compliance examines how a tax authority can maximize social welfare by trading-off audit probability against the fine rate on undeclared tax. This paper offers...

  20. The angular momentum of baryons and dark matter halos revisited

    OpenAIRE

    Kimm, Taysun; Devriendt, Julien; Slyz, Adrianne; Pichon, Christophe; Kassin, Susan A.; Dubois, Yohan

    2011-01-01

    Recent theoretical studies have shown that galaxies at high redshift are fed by cold, dense gas filaments, suggesting angular momentum transport by gas differs from that by dark matter. Revisiting this issue using high-resolution cosmological hydrodynamics simulations with adaptive mesh refinement, we find that at the time of accretion, gas and dark matter do carry a similar amount of specific angular momentum, but that it is systematically higher than that of the dark matter halo as a whole....

  1. Trade and civil conflict : revisiting the cross-country evidence

    OpenAIRE

    Cali, Massimiliano; Mulabdic, Alen

    2014-01-01

    This paper revisits and expands the evidence on the impact of trade shocks on intra-state conflict with a large sample of developing countries in the 1960-2010 period. The results suggest that increases in the prices of a country's exported commodities raise the country's risk of civil conflict and its duration. The effect on conflict risk is mainly driven by the price of point-source comm...

  2. Simulation of Two-Way Pushdown Automata Revisited

    OpenAIRE

    Robert Glück

    2013-01-01

    The linear-time simulation of 2-way deterministic pushdown automata (2DPDA) by the Cook and Jones constructions is revisited. Following the semantics-based approach by Jones, an interpreter is given which, when extended with random-access memory, performs a linear-time simulation of 2DPDA. The recursive interpreter works without the dump list of the original constructions, which makes Cook's insight into linear-time simulation of exponential-time automata more intuitive and the complexity arg...

  3. Probit Model Estimation Revisited: Trinomial Models of Household Car Ownership

    OpenAIRE

    Bunch, David S; Kitamura, Ryuichi

    1991-01-01

    In this paper we revisit various important issues relating to practical estimation of the multinomial probit model, using an empirical analysis of car ownership as a test case. To provide context, a brief literature review of empirical probit studies is included. Estimates are obtained for a full range of model specifications, including models with random (uncorrelated and correlated) taste variation and/or a general random error structure, and issues of estimability, specification testing, a...

  4. Power Market Design beyond 2020: Time to Revisit Key Elements?

    OpenAIRE

    Neuhoff, Karsten; Ruester, Sophia; Schwenen, Sebastian

    2015-01-01

    We revisit key elements of European power market design with respect to both short term operation and longer-term investment and re-investment choices. For short term markets, the European policy debate focuses on the definition of common interfaces, like for example gate closure time. We argue that that this is insufficient if the market design is to accommodate for the different needs of renewable and conventional generation assets and different flexibility options. The market design needs ...

  5. New Families in the Stable Homotopy of Spheres Revisited

    Institute of Scientific and Technical Information of China (English)

    LIN Jin Kun

    2002-01-01

    This paper constructs a new family in the stable homotopy of spheres πt-6S representedby hngoγ3 ∈ E26,t in the Adams spectral sequence which revisits the bn-1g0γ3-elements ∈πt-7S con-structed in [3], where t = 2pn(p- 1) +6(p2 + p+ 1)(p- 1) and p ≥ 7 is a prime, n ≥ 4.

  6. Revisiting Barriers to Trade: Do Foregone Health Benefits Matter?

    OpenAIRE

    Zhang, Sidi; Kerr, William A.

    2009-01-01

    This paper examins the question of revisiting the imposition of existing trade barriers in one case of an evolving marketplace – when a traditional food product is altered to provide, or discovered to have, human health benefits that increases their value to consumers. In other words, the food becomes a functional food. A functional food has the potential provide direct benefits to consumers as well as indirect benefits to society in the form of health care cost savings. If the trade barrier ...

  7. The Dutch Disease revisited: absorption constraint and learning by doing

    OpenAIRE

    Iacono, Roberto

    2014-01-01

    This paper revisits the Dutch disease by analyzing the general equilibrium effects of a resource shock on a dependent economy, both in a static and dynamic setting. The novel aspect of this study is to incorporate two features of the Dutch disease literature that have only been analyzed in isolation from each other: capital accumulation with absorption constraint and productivity growth induced by learning by doing. The conventional result of long-run exchange rate appreciation is maintained ...

  8. Clausius/Cosserat/Maxwell/Weyl Equations: The Virial Theorem Revisited

    OpenAIRE

    Pommaret, Jean-François

    2015-01-01

    This paper must be published under the title " FROM THERMODYNAMICS TO GAUGE THEORY: THE VIRIAL THEOREM REVISITED " as a chapter of a forthcoming book " GAUGE THEORY AND DIFFERENTIAL GEOMETRY " published by Nova Editors. In 1870, R. Clausius found the virial theorem which amounts to introduce the trace of the stress tensor when studying the foundations of thermodynamics, as a way to relate the absolute temperature of an ideal gas to the mean kinetic energy of its molecules. In 1901, H. Poin...

  9. Radiative Corrections to Neutrino Deep Inelastic Scattering Revisited

    CERN Document Server

    Arbuzov, A B; Kalinovskaya, L V

    2005-01-01

    Radiative corrections to neutrino deep inelastic scattering are revisited. One-loop electroweak corrections are re-calculated within the automatic SANC system. Terms with mass singularities are treated including higher order leading logarithmic corrections. Scheme dependence of corrections due to weak interactions is investigated. The results are implemented into the data analysis of the NOMAD experiment. The present theoretical accuracy in description of the process is discussed.

  10. Revisiting the Response Mechanism of Polymeric Membrane Based Heparin Electrodes

    OpenAIRE

    Bell, Andrea K.; Höfler, Lajos; Meyerhoff, Mark E.

    2011-01-01

    Potentiometric membrane electrodes that respond to heparin and other polyanions were introduced in the early 1990s. Herein, the mechanism of polymer membrane electrode type heparin sensors is revisited. The extraction/diffusion of heparin is studied via both potentiometric and impedance spectroscopic techniques using a pre-fractionated heparin preparation that contains polyanionic species > 10000 Daltons. The reversal in EMF response using this heparin preparation indicates diffusion of highe...

  11. 四氯化碳液相催化加氢反应动力学的研究%KINETIC STUDIES ON THE CATALYTIC HYDROGENATION OF CARBON TETRACHLORIDE TO CHLOROFORM IN LIQUID PHASE

    Institute of Scientific and Technical Information of China (English)

    毛建新; 蒋晓原; 陆维敏; 郑小明

    2001-01-01

    Carbon tetrachloride is an ozone-depleting chemical, while chloroform is not. Therefore it is important for the catalytic hydrodechlorination of CCl4 to CHCl3. In this paper, kinetics on the catalytic hydrogenation of carbon tetrachloride to chloroform in liquid phase was studied. A reaction mechanism was proposed. Hydrogen molecular was activated on the surface of catalyst, the activated hydrogen atom then reacted with CCl4 in the solution and produced CHCl3. A definite kinetic equation could be deduced from the reaction mechanism. The reaction rate constant is concerned with the intial concentration of CCl4 in the solution, pressure, reaction temperature and the concentration of active center. All these factors were investigated over Pt-Pd/C catalyst and fit in with the kinetic equation. The activation energy of the reaction is 86?KJ/mol according to the experimental results.

  12. Determination of glyphosate and aminomethylphosphonic acid in aqueous soil matrices: a critical analysis of the 9-fluorenylmethyl chloroformate derivatization reaction and application to adsorption studies.

    Science.gov (United States)

    Báez, María E; Fuentes, Edwar; Espina, María José; Espinoza, Jeannette

    2014-11-01

    The assessment of the environmental fate of glyphosate and its degradation product (aminomethylphosphonic acid) is of great interest given the widespread use of the herbicide. Studies of adsorption-desorption and transport processes in soils require analytical methods with sensitivity, accuracy, and precision suitable for determining the analytes in aqueous equilibrium solutions of varied complexity. In this work, the effect of factors on the yield of the derivatization of both compounds with 9-fluorenylmethyl chloroformate for applying in aqueous solutions derived from soils was evaluated through factorial experimental designs. Interference effects coming from background electrolytes and soil matrices were established. The whole method had a linear response up to 640 ng/mL (R(2) > 0.999) under optimized conditions for high-performance liquid chromatography with fluorescence detection. Limits of detection were 0.6 and 0.4 ng/mL for glyphosate and aminomethylphosphonic acid, respectively. The relative standard deviation was 4.4% for glyphosate (20 ng/mL) and 5.9% for aminomethylphosphonic acid (10 ng/mL). Adsorption of compounds on four different soils was assessed. Isotherm data fitted well the Freundlich model (R(2) > 0.97). Kf constants varied between 93 ± 3.1 and 2045 ± 157 for glyphosate and between 99 ± 4.1 and 1517 ± 56 (μg(1-1/) (n)  mL(1/) (n) ( ) g(-1) ) for aminomethylphosphonic acid, showing the broad range of applicability of the proposed method.

  13. Determination of glyphosate and aminomethylphosphonic acid in aqueous soil matrices: a critical analysis of the 9-fluorenylmethyl chloroformate derivatization reaction and application to adsorption studies.

    Science.gov (United States)

    Báez, María E; Fuentes, Edwar; Espina, María José; Espinoza, Jeannette

    2014-11-01

    The assessment of the environmental fate of glyphosate and its degradation product (aminomethylphosphonic acid) is of great interest given the widespread use of the herbicide. Studies of adsorption-desorption and transport processes in soils require analytical methods with sensitivity, accuracy, and precision suitable for determining the analytes in aqueous equilibrium solutions of varied complexity. In this work, the effect of factors on the yield of the derivatization of both compounds with 9-fluorenylmethyl chloroformate for applying in aqueous solutions derived from soils was evaluated through factorial experimental designs. Interference effects coming from background electrolytes and soil matrices were established. The whole method had a linear response up to 640 ng/mL (R(2) > 0.999) under optimized conditions for high-performance liquid chromatography with fluorescence detection. Limits of detection were 0.6 and 0.4 ng/mL for glyphosate and aminomethylphosphonic acid, respectively. The relative standard deviation was 4.4% for glyphosate (20 ng/mL) and 5.9% for aminomethylphosphonic acid (10 ng/mL). Adsorption of compounds on four different soils was assessed. Isotherm data fitted well the Freundlich model (R(2) > 0.97). Kf constants varied between 93 ± 3.1 and 2045 ± 157 for glyphosate and between 99 ± 4.1 and 1517 ± 56 (μg(1-1/) (n)  mL(1/) (n) ( ) g(-1) ) for aminomethylphosphonic acid, showing the broad range of applicability of the proposed method. PMID:25137606

  14. Chloroform Fraction of Centratherum anthelminticum (L. Seed Inhibits Tumor Necrosis Factor Alpha and Exhibits Pleotropic Bioactivities: Inhibitory Role in Human Tumor Cells

    Directory of Open Access Journals (Sweden)

    Aditya Arya

    2012-01-01

    Full Text Available We investigated the antioxidant potential, cytotoxic effect, and TNF-α inhibition activity with NF-κB activation response in a chloroform fraction of Centratherum anthelminticum seeds (CACF. The antioxidant property of CACF was evaluated with DPPH, ORAC, and FRAP assays, which demonstrated significant antioxidant activity. The cytotoxicity of CACF was tested using the MTT assay; CACF effective inhibitory concentrations (IC50 for A549, PC-3, MCF-7, and WRL-68 cells were 31.42±5.4, 22.61±1.7, 8.1±0.9, and 54.93±8.3 μg/mL, respectively. CACF effectively and dose-dependently inhibited TNF-α release, in vitro and in vivo. CACF inhibited TNF-α secretion in stimulated RAW264.7 macrophage supernatants with an IC50 of 0.012 μg/mL, without affecting their viability; the highest dose tested reduced serum TNF-α by 61%. Acute toxicity testing in rats revealed that CACF was non-toxic at all doses tested. Matching the cytotoxic activity towards a mechanistic approach, CACF dose-dependently exhibited in vitro inhibitory effects against the activation of NF-κB translocation in MCF-7 cells. Preliminary phytochemical screening with GC/MS analysis detected 22 compounds in CACF, of which morpholinoethyl isothiocyanate was the most abundant (29.04%. The study reveals the potential of CACF in the treatment of breast cancer and in oxidative stress conditions with associated inflammatory responses.

  15. Positive and Negative Contributions in the Solvation Enthalpy due to Specific Interactions in Binary Mixtures of C1-C4 n-Alkanols and Chloroform with Butan-2-one.

    Science.gov (United States)

    Varfolomeev, Mikhail A; Rakipov, Ilnaz T; Solomonov, Boris N; Lodowski, Piotr; Marczak, Wojciech

    2015-06-25

    In the paper, results of calorimetric measurements, IR spectra, and calculated ab initio stabilization energies of dimers are reported for binary systems butan-2-one + (methanol, ethanol, propan-1-ol, butan-1-ol, and chloroform). Changes in the total enthalpy of specific interactions due to dissolution of butan-2-one in the alcohols, calculated using equations derived in previous works, are positive. That results from the endothermic breaking of the O-H···O-H bonds not completely compensated by the exothermic effects of formation of the O-H···O═C ones. Moreover, the concentration of nonbonded molecules of butan-2-one is significant even in dilute solutions, as is evidenced by the shape of the C═O stretching vibrations band in the IR spectra. Apart from that, the spectra do not confirm 1:2 complexes in spite of two lone electron pairs in the carbonyl group of butan-2-one capable of forming the hydrogen bonds. The changes in enthalpy of specific interactions are negative for dilute solutions of alcohols and chloroform in butan-2-one and of butan-2-one in chloroform, because no hydrogen bonds occur in pure butan-2-one. The experimental results are positively correlated with the enthalpies estimated from the ab initio energies using a simple "chemical reaction" approach. PMID:26012694

  16. Positive and Negative Contributions in the Solvation Enthalpy due to Specific Interactions in Binary Mixtures of C1-C4 n-Alkanols and Chloroform with Butan-2-one.

    Science.gov (United States)

    Varfolomeev, Mikhail A; Rakipov, Ilnaz T; Solomonov, Boris N; Lodowski, Piotr; Marczak, Wojciech

    2015-06-25

    In the paper, results of calorimetric measurements, IR spectra, and calculated ab initio stabilization energies of dimers are reported for binary systems butan-2-one + (methanol, ethanol, propan-1-ol, butan-1-ol, and chloroform). Changes in the total enthalpy of specific interactions due to dissolution of butan-2-one in the alcohols, calculated using equations derived in previous works, are positive. That results from the endothermic breaking of the O-H···O-H bonds not completely compensated by the exothermic effects of formation of the O-H···O═C ones. Moreover, the concentration of nonbonded molecules of butan-2-one is significant even in dilute solutions, as is evidenced by the shape of the C═O stretching vibrations band in the IR spectra. Apart from that, the spectra do not confirm 1:2 complexes in spite of two lone electron pairs in the carbonyl group of butan-2-one capable of forming the hydrogen bonds. The changes in enthalpy of specific interactions are negative for dilute solutions of alcohols and chloroform in butan-2-one and of butan-2-one in chloroform, because no hydrogen bonds occur in pure butan-2-one. The experimental results are positively correlated with the enthalpies estimated from the ab initio energies using a simple "chemical reaction" approach.

  17. Study on Antimicrobial Activity and Stability of Chloroform Phase of Zingiber officinale Roscoe Extract%大肉姜提取物氯仿相的抑菌效果及稳定性研究

    Institute of Scientific and Technical Information of China (English)

    韦学丰; 邓年方; 杨君军; 蒙英升

    2015-01-01

    In order to study the antimicrobial activity of Zingiber officinale Roscoe extracts,the chloroform phase is selected as the research object after fractional extraction.Echerichia coli, Staphylo-coccus aureus and Saccharomyces cere-visiae are selected as the indicator bacteria and the antimicrobial effect is as the evaluating indicator,the antimicrobial activity of chloroform phase and total extracts are compared,the effects of temperature,pH value on the inhibitory activity of total extracts and chloroform phase are studied as well. The results show that Echerichia coli, Staphylo-coccus aureus and Saccharomyces cere-visiae are inhibited by both the total extracts and the chloroform phase,but the inhibitory effects are different on strains.The pH value and heat treatment have obvious impact on the stability of chloroform phase,but have little impact on the total extracts.%为了研究大肉姜提取物化学成分的抑菌性能,对大肉姜总提取物进行分级萃取,以氯仿相为研究对象,以大肠杆菌、金黄色葡萄球菌和酒精酵母为指示菌,以抑菌效果为评价指标,比较了氯仿相与总提取物的抑菌性能,并考察了温度、pH 值对总提取物和氯仿相抑菌活性的影响。结果表明:氯仿相和总提取物对大肠杆菌、金黄色葡萄球菌和酒精酵母均有一定的抑制作用,但对不同菌种的抑菌效果存在一定差异,pH 值和热处理对氯仿相抑菌稳定性影响较大,对总提取物的抑菌稳定性影响较小。

  18. Circular revisit orbits design for responsive mission over a single target

    Science.gov (United States)

    Li, Taibo; Xiang, Junhua; Wang, Zhaokui; Zhang, Yulin

    2016-10-01

    The responsive orbits play a key role in addressing the mission of Operationally Responsive Space (ORS) because of their capabilities. These capabilities are usually focused on supporting specific targets as opposed to providing global coverage. One subtype of responsive orbits is repeat coverage orbit which is nearly circular in most remote sensing applications. This paper deals with a special kind of repeating ground track orbit, referred to as circular revisit orbit. Different from traditional repeat coverage orbits, a satellite on circular revisit orbit can visit a target site at both the ascending and descending stages in one revisit cycle. This typology of trajectory allows a halving of the traditional revisit time and does a favor to get useful information for responsive applications. However the previous reported numerical methods in some references often cost lots of computation or fail to obtain such orbits. To overcome this difficulty, an analytical method to determine the existence conditions of the solutions to revisit orbits is presented in this paper. To this end, the mathematical model of circular revisit orbit is established under the central gravity model and the J2 perturbation. A constraint function of the circular revisit orbit is introduced, and the monotonicity of that function has been studied. The existent conditions and the number of such orbits are naturally worked out. Taking the launch cost into consideration, optimal design model of circular revisit orbit is established to achieve a best orbit which visits a target twice a day in the morning and in the afternoon respectively for several days. The result shows that it is effective to apply circular revisit orbits in responsive application such as reconnoiter of natural disaster.

  19. A practical method of predicting client revisit intention in a hospital setting.

    Science.gov (United States)

    Lee, Kyun Jick

    2005-01-01

    Data mining (DM) models are an alternative to traditional statistical methods for examining whether higher customer satisfaction leads to higher revisit intention. This study used a total of 906 outpatients' satisfaction data collected from a nationwide survey interviews conducted by professional interviewers on a face-to-face basis in South Korea, 1998. Analyses showed that the relationship between overall satisfaction with hospital services and outpatients' revisit intention, along with word-of-mouth recommendation as intermediate variables, developed into a nonlinear relationship. The five strongest predictors of revisit intention were overall satisfaction, intention to recommend to others, awareness of hospital promotion, satisfaction with physician's kindness, and satisfaction with treatment level. PMID:15923917

  20. Profiling of urinary amino-carboxylic metabolites by in-situ heptafluorobutyl chloroformate mediated sample preparation and gas chromatography-mass spectrometry.

    Science.gov (United States)

    Hušek, Petr; Švagera, Zdeněk; Hanzlíková, Dagmar; Řimnáčová, Lucie; Zahradníčková, Helena; Opekarová, Iva; Šimek, Petr

    2016-04-22

    A novel 1,1,1,2,2,3,3-heptafluorobutyl chloroformate reagent (HFBCF) was examined for in-situ derivatization of amino-carboxylic metabolites in human urine. The arising reaction products exhibit greatly reduced polarity which facilitates combining the derivatization and liquid-liquid microextraction (LLME) from an aqueous urine into an isooctane phase and immediate gas chromatographic-mas spectrometric analysis (GC-MS). The sample preparation protocol is simple, proceeds without an alcohol excess and provides cleaner extracts than other urinary GC-MS based methods. Moreover, thiol metabolites bound in disulfide bonds can be released by reduction with tris(3-hydroxypropyl)phosphine (THP) prior to the developed derivatization and LLME step. In order to evaluate potential of the novel method for GC-MS metabolomics, reaction products of 153 urinary metabolites with HFBCF, particularly those possessing amino and carboxyl groups (56 amino acids and their conjugates, 84 organic acids, 9 biogenic amines, 4 other polar analytes) and two internal standards were investigated in detail by GC-MS and liquid chromatography-mass spectrometry (LC-MS). One hundred and twenty metabolites (78%) yielded a single product, 25 (16%) and 2 metabolites (2-methylcitrate, citrate) generated two and more derivatives. From the examined set, analytically applicable products of 5 metabolites were not detected; the derivatives of 3 metabolites were only suitable for LC-MS analysis. Electron ionization (EI) of the examined analytes contained characteristic, diagnostic ions enabling to distinguish related and isomeric structures. The new method was validated for 132 metabolites using two internal standards in artificial urine and with special attention to potential disease biomarker candidates. The developed sample preparation protocol was finally evaluated by means of a certified organic acid standard mixture in urine and by GC-MS analysis of 100 morning urines obtained from healthy patients (50

  1. Fresh Preservation of Cowpea with Extracts of Millettia specisoa Champ Isolated with Chloroform%牛大力氯仿提取物保鲜豇豆研究

    Institute of Scientific and Technical Information of China (English)

    张苏敏; 李天略; 刘艺洁; 陈光英; 史载锋

    2012-01-01

    [目的]研究牛大力氯仿提取物的乙醇水溶液对豇豆的保鲜作用.[方法]将豇豆在不同浓度牛大力氯仿提取物中浸泡,然后取出在空气中晾干存放.在存放过程中,测定豇豆表观、失重率、pH、总糖含量以及Vc含量的变化来分析其保鲜效果.[结果]用浓度为6 ml/L的牛大力氯仿提取物乙醇水溶液浸泡的豇豆样品,好果率、失重率、pH、Vc含量、总糖含量的变化幅度均较小,保鲜效果最佳,保鲜期比不经任何处理的豇豆延长2d.[结论]研究可为天然植物提取物用于果蔬保鲜的开发应用提供参考依据.%[Objective] To study the preservation effects of cowpea with extracts of Millettia specisoa Champ isolated with chloroform. [Method ] Cowpeas were immersed in alcohol-water solution of the extracts, then stored in the open-air at room temperature after dried out. Changes of the factors such as apparent, weight loss, pH value, VC and total sugar contents were determined during the preservation process. [ Result ] The results indicated that it gives the best fresh reservation effects on cowpea with the extracts concentration of 6 ml/L, changes of all factors are the smallest. It is to say that the extracts may show good preservation effect on cowpeas at proper conditions, the keeping fresh time is 2 days longer than that without any preservation treatment. [Conclusion] The study provides reference basis for utilization of natural plant extracts in fruit and vegetable preservation.

  2. Fourth-order gravity as the inflationary model revisited

    CERN Document Server

    Kaneda, S; Watanabe, N

    2010-01-01

    We revisit the simplest (fourth-order or quadratically generated) modified gravity model in four space-time dimensions. It is equivalent to the certain quintessence model via a Legendre-Weyl transform. By using the quintessence scalar potential we compute the (CMB) observables of inflation associated with curvature perturbations (namely, the scalar and tensor spectral indices, and the tensor-to-scalar ratio) by using the most recent WMAP5 experimental bound. Our results include the next-to-leading terms with respect to the inverse number of e-foldings.

  3. Revisiting the issue of elite capture in participatory initiatives

    DEFF Research Database (Denmark)

    Lund, Jens Friis; Saito-Jensen, Moeko

    2013-01-01

    of resistance orchestrated by initially disadvantaged groups. Based on the cases we argue that studies of elite capture should be based on in-depth and longitudinal empirical investigations that carefully characterize forms and outcomes of elite capture and consider both the changing dynamics of social settings......Based on case studies of two communities implementing participatory forestry in Tanzania and India, we revisit the issue of elite capture of participatory initiatives. Our cases illustrate how initial elite capture of the participatory initiatives is circumvented over time through various forms...

  4. Hyperbranched polymer stars with Gaussian chain statistics revisited.

    Science.gov (United States)

    Polińska, P; Gillig, C; Wittmer, J P; Baschnagel, J

    2014-02-01

    Conformational properties of regular dendrimers and more general hyperbranched polymer stars with Gaussian statistics for the spacer chains between branching points are revisited numerically. We investigate the scaling for asymptotically long chains especially for fractal dimensions df = 3 (marginally compact) and df = 2.5 (diffusion limited aggregation). Power-law stars obtained by imposing the number of additional arms per generation are compared to truly self-similar stars. We discuss effects of weak excluded-volume interactions and sketch the regime where the Gaussian approximation should hold in dense solutions and melts for sufficiently large spacer chains. PMID:24574057

  5. Revisiting perfect fluid dark matter: Observational constraints from our galaxy

    OpenAIRE

    Potapov, Alexander A.; Garipova, Guzel M.; Nandi, Kamal K.

    2016-01-01

    We revisit certain features of an assumed spherically symmetric perfect fluid dark matter halo in the light of the observed data of our galaxy, the Milky Way (MW). The idea is to apply the Faber–Visser approach of combined observations of rotation curves and lensing to a first post-Newtonian approximation to “measure” the equation of state ω(r) of the perfect fluid galactic halo. However, for the model considered here, no constraints from lensing are used as it will be sufficient to consider ...

  6. Sampling the equilibrium: the j-walking algorithm revisited

    CERN Document Server

    Rimas, Zilvinas

    2016-01-01

    The j-walking Monte-Carlo algorithm is revisited and updated to study the equilibrium properties of a system exhibiting broken ergodicity. The updated algorithm is tested on the Ising model and applied to the lattice-gas model for sorption in aerogel at low temperatures, when dynamics of the system is critically slowed down. It is demonstrated that the updated j-walking simulations are able to produce equilibrium isotherm which are typically hidden by the hysteresis effect within the standard single-flip simulations.

  7. Nonextensive Nambu Jona-Lasinio model of QCD matter revisited

    CERN Document Server

    Rozynek, Jacek

    2016-01-01

    We present a revisited version of the nonextensive QCD-based Nambu - Jona-Lasinio (NJL) model describing the behavior of strongly interacting matter proposed by us some time ago. As before, it is based on the nonextensive generalization of the Boltzmann-Gibbs (BG) statistical mechanics used in the NJL model to its nonextensive version based on Tsallis statistics, but this time it fulfils the basic requirements of thermodynamical consistency. Different ways in which this can be done, connected with different possible choices of the form of the corresponding nonextensive entropies, are presented and discussed in detail. The corresponding results are compared, discussed and confronted with previous findings.

  8. Closed-set-based Discovery of Representative Association Rules Revisited

    CERN Document Server

    Balcázar, José L

    2010-01-01

    The output of an association rule miner is often huge in practice. This is why several concise lossless representations have been proposed, such as the "essential" or "representative" rules. We revisit the algorithm given by Kryszkiewicz (Int. Symp. Intelligent Data Analysis 2001, Springer-Verlag LNCS 2189, 350-359) for mining representative rules. We show that its output is sometimes incomplete, due to an oversight in its mathematical validation, and we propose an alternative complete generator that works within only slightly larger running times.

  9. Revisiting reflexology: Concept, evidence, current practice, and practitioner training

    OpenAIRE

    Embong, Nurul Haswani; Soh, Yee Chang; Ming, Long Chiau; Wong, Tin Wui

    2015-01-01

    Reflexology is basically a study of how one part of the human body relates to another part of the body. Reflexology practitioners rely on the reflexes map of the feet and hands to all the internal organs and other human body parts. They believe that by applying the appropriate pressure and massage certain spots on the feet and hands, all other body parts could be energized and rejuvenated. This review aimed to revisit the concept of reflexology and examine its effectiveness, practices, and th...

  10. Small-angle scattering theory revisited: Photocurrent and spatial localization

    DEFF Research Database (Denmark)

    Basse, N.P.; Zoletnik, S.; Michelsen, Poul

    2005-01-01

    In this paper theory on collective scattering measurements of electron density fluctuations in fusion plasmas is revisited. We present the first full derivation of the expression for the photocurrent beginning at the basic scattering concepts. Thereafter we derive detailed expressions for the auto......- and crosspower spectra obtained from measurements. These are discussed and simple simulations made to elucidate the physical meaning of the findings. In this context, the known methods of obtaining spatial localization are discussed and appraised. Where actual numbers are applied, we utilize....... Saffman et al., "CO2 laser based two-volume collective scattering instrument for spatially localized turbulence measurements,"Rev. Sci. Instrum. 72, 2579-2592 (2001)]....

  11. OP-7/氯仿反胶束体系的制备及其增溶水量的研究%Study on preparation of OP-7/chloroform reverse micelle systems and their water solubilization performance

    Institute of Scientific and Technical Information of China (English)

    赵群; 陈怡秀; 朱青; 沈炎冰; 邓龙根; 马超; 阎克路

    2013-01-01

    The novel OP-7/chloroform reverse micelle system have been prepared by substituting chloroform for the alkanes of traditional reverse micelle systems,and the water solubilization behaviors of the systems have been investigated.The impact of OP-7' s concentration and the type of cosurfactant on the water solubilization amount of reverse micelle systems and the relationship between the water solubilization amount and the size and the conductivity of the systems were studied.The results showed that both the dosage of OP-7,the type and the concentration of the alcohol as cosufactant affect the water solubilization amount ; at the same time,the size and conductivity of the systems increased with increasing water solubilization amount,the OP-7/n-octanol/chloroform has the maximum water solubilization amount.%以氯仿代替传统的烃类溶剂,制备新型OP-7(非离子表面活性剂)/氯仿反胶束体系,并对该体系的增溶行为进行研究.考察了OP-7的浓度和不同的助表面活性剂对该体系增溶水量的影响及增溶水量与体系的粒径、电导率的关系.结果表明,OP-7的浓度、助表面活性剂醇的种类和用量都影响着体系的增溶水量;同时增溶水量增加,体系的粒径和电导率随之增加,OP-7/正辛醇/氯仿反胶束体系增溶水量最大.

  12. Comparison of phenol chloroform method and salting out method for genomic DNA extraction%酚/氯仿法和盐析法提取人类外周血基因组DNA方法的比较

    Institute of Scientific and Technical Information of China (English)

    宋洁云; 刘芳宏; 马军; 陈远帆; 王海俊

    2013-01-01

    目的 比较两种不同方法提取的基因组DNA的纯度、产量和后续实验效果.方法 采用酚/氯仿法和盐析法两种方法直接从全血中提取基因组DNA,并采用电泳、PCR和基质支持的激光释放/电离飞行时间质谱分析(MALDI-TOF MS)方法进行检测.结果 酚/氯仿法提取的基因组DNA纯度高于盐析法(P<0.001),但两组纯度平均值都高于1.80;没有发现两种方法提取的DNA浓度存在差异(P=0.819).两组DNA在电泳中都没有出现明显拖尾现象,均很容易扩增出胰岛素诱导基因2片段,并且在MALDI-TOF MS检测中,两组DNA样本结果没有明显差异.结论 酚/氯仿法和盐析法提取的基因组DNA质量无明显差异.相比酚/氯仿法,盐析法能简便、快速、无毒地进行DNA提取,适合于大规模的分子生物学实验.%Objective To detect the purity,quantity and follow-up experimental effects of DNA extracted with two methods. Methods Extract genomic DNA with phenol chloroform method and salting out method,and detect the DNA samples with electrophoresis, PCR and Matrix-Assisted Laser Desorption/ Ionization Time of Flight Mass Spectrome try (MALDI-TOF MS). Results Purity of DNA extracted with phenol chloroform method was higher than that with salting out method,with both mean purity higher than 1.80. The quantity was not significantly different between two methods (P=0. 819). The DNA samples did not smear on gel,and the PCR test of INSIG2 gene and MALD1-TOF MS test did not show difference between DNA isolated with two methods. Conclusion There was no difference between DNA samples isolated with phenol chloroform method and salting out method. Compared to phenol chloroform method, salting out method was much simpler, more quick and harmless, and was applicable to molecular biology experiments with large scale.

  13. DMPD: TLR signalling and activation of IRFs: revisiting old friends from the NF-kappaBpathway. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16006187 TLR signalling and activation of IRFs: revisiting old friends from the NF-kappaBpath...nalling and activation of IRFs: revisiting old friends from the NF-kappaBpathway. PubmedID 16006187 Title TL...R signalling and activation of IRFs: revisiting old friends from the NF-kappaBpath

  14. Acaricidal activity of four fractions and octadecanoic acid-tetrahydrofuran-3,4-diyl ester isolated from chloroform extracts of neem (Azadirachta indica) oil against Sarcoptes scabiei var. cuniculi larvae in vitro.

    Science.gov (United States)

    Du, Yong-Hua; Li, Jin-Liang; Jia, Ren-Yong; Yin, Zhong-Qiong; Li, Xu-Ting; Lv, Cheng; Ye, Gang; Zhang, Li; Zhang, Yu-Qun

    2009-07-01

    Four fractions obtained from chloroform extracts of neem (Azadirachta indica) oil by column chromatography were investigated for acaricidal activity against Sarcoptes scabiei var. cuniculi larvae in vitro. Octadecanoic acid-tetrahydrofuran-3,4-diyl ester was isolated from an active fraction of the chloroform extract and its toxicity against S. scabiei larvae was tested in vitro. A complementary log-log model was used to analyse the toxicity data. Activity was found in the third fraction, with 100% corrected mortality after 4.5 h of exposure at a concentration of 200 mg ml(-1). This fraction was repeatedly re-crystallised in acetone to yield a white amorphous powder, identified as octadecanoic acid-tetrahydrofuran-3,4-diyl ester, with a median lethal concentration (LC(50)) of 0.1 mg ml(-1) at 24 h post-treatment. The median lethal time (LT(50)) for this compound was 15.3 h at a concentration of 7.5 mg ml(-1). PMID:19443124

  15. Phytochemistry and Preliminary Assessment of the Antibacterial Activity of Chloroform Extract of Amburana cearensis (Allemão A.C. Sm. against Klebsiella pneumoniae Carbapenemase-Producing Strains

    Directory of Open Access Journals (Sweden)

    Mirivaldo Barros Sá

    2014-01-01

    Full Text Available The chloroform extract of the stem bark of Amburana cearensis was chemically characterized and tested for antibacterial activity.The extract was analyzed by gas chromatography and mass spectrometry. The main compounds identified were 4-methoxy-3-methylphenol (76.7%, triciclene (3.9%, α-pinene (1.0%, β-pinene (2.2%, and 4-hydroxybenzoic acid (3.1%. Preliminary antibacterial tests were carried out against species of distinct morphophysiological characteristics: Escherichia coli, Salmonella enterica Serotype Typhimurium, Pseudomonas aeruginosa, Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus. The minimum inhibitory concentration (MIC was determinate in 96-well microplates for the chloroform extract and an analogue of themain compound identified, which was purchased commercially.We have shown that plant’s extract was only inhibitory (but not bactericidal at the maximum concentration of 6900 μg/mL against Pseudomonas aeruginosa and Bacillus cereus. Conversely, the analogue 2-methoxy-4-methylphenol produced MICs ranging from215 to 431 μg/mL against all bacterial species.New antibacterial assays conducted with such chemical compound against Klebsiella pneumoniae carbapenemase-producing strains have shown similarMICresults and minimumbactericidal concentration (MBC of 431 μg/mL.We conclude that A. cearensis is a good source of methoxy-methylphenol compounds,which could be screened for antibacterial activity againstmultiresistant bacteria fromdifferent species

  16. (η(6)-Benzene)(carbonato-κ(2) O,O')[di-cyclohex-yl(naphthalen-1-ylmeth-yl)phosphane-κP]ruthenium(II) chloro-form tris-olvate.

    Science.gov (United States)

    Gowrisankar, Saravanan; Neumann, Helfried; Spannenberg, Anke; Beller, Matthias

    2014-07-01

    The title compound, [Ru(CO3)(η(6)-C6H6){(C6H11)2P(CH2C10H7)}]·3CHCl3, was synthesized by carbonation of [RuCl2(η(6)-C6H6){(C6H11)2P(CH2C10H7)}] with NaHCO3 in methanol at room temperature. The Ru(II) atom is surrounded by a benzene ligand, a chelating carbonate group and a phosphane ligand in a piano-stool configuration. The crystal packing is consolidated by C-H⋯O and C-H⋯Cl hydrogen-bonding inter-actions between adjacent metal complexes and between the complexes and the solvent mol-ecules. The asymmetric unit contains one metal complex and three chloro-form solvent mol-ecules of which only one was modelled. The estimated diffraction contributions of the other two strongly disordered chloro-form solvent mol-ecules were substracted from the observed diffraction data using the SQUEEZE procedure in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. PMID:25161531

  17. Revisiting Neoclassical Growth Theory: A Survey in the Literature

    Directory of Open Access Journals (Sweden)

    Mayank GUPTA

    2015-03-01

    Full Text Available Abstract During the second half of the twentieth century economists have build newer models of economic growth that consider policy influences of growth and divergent outcomes among countries. These models addresses issues concerning economic growth, operation of financial markets, trade policy, government expenditures, and taxation. In this essay we have revisited the interdependence of political and economic institutions, taking the neoclassical growth model of Solow (1956 as a point of departure, which maintains that long run economic growth can be explained by capital accumulation, population growth and technological progress. We first discuss the evolution of the neoclassical school of economics in a historical context, and the role of various institutions in engendering economic growth. Subsequently the role of government spending, political stability, property rights and special interest groups (SIG's affect economic growth have been discussed, and how these institutions can explain different countries to grow at divergent rates and achieve different levels of wealth.

  18. Semiclassical approach for the evaporating black hole revisited

    Science.gov (United States)

    Gim, Yongwan; Kim, Wontae

    2016-01-01

    A recent calculation shows that the observed energy density in the Unruh state at the future event horizon as seen by a freely falling observer is finite if the observer is released from rest at any positive distance outside the horizon; however, it is getting larger and larger so that it is negatively divergent at the horizon in the limit that the observer starts falling from rest at the horizon, which corresponds to the infinite boost with respect to the freely falling observer at a finite distance from the horizon. In order to resolve some conflicts between the recent calculation and the conventional ones in the well-known literatures, the calculation of the free-fall energy density is revisited and some differences are pointed out.

  19. Revisiting manufacturing strategy: contributions towards a new construct

    Directory of Open Access Journals (Sweden)

    Eliciane Maria da Silva

    2008-07-01

    Full Text Available This paper aims at revisiting and systematizing the literature on manufacturing strategy. Although this is a well consolidated theme broadly discussed in the last fifty years, manufacturing strategy practice grew on importance recently due to a more competitive environment the companies find themselves in. The review carried has systematized the existing literature into six lines of research dealing with competitive priorities, structural and infrastructural decision, best practices, performance indicators, production strategy formulation and generic manufacturing strategies. This article shows that four out of the six research areas are still receiving attention. A new construct which represents a global view of the lines of research mentioned is proposed. Gaps in the research field and suggestions for future works are described. Keywords: manufacturing strategy, content, formulation of manufacturing strategy, competitive priorities, best practices, performance indicators.

  20. Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited

    DEFF Research Database (Denmark)

    Martens, Pernille; Worm, Signe Westring; Lundgren, Bettina;

    2004-01-01

    Serotype-specific mortality from invasive Streptococcus pneumoniae disease revisited.Martens P, Worm SW, Lundgren B, Konradsen HB, Benfield T. Department of Infectious Diseases 144, Hvidovre University Hospital, DK-2650 Hvidovre, Denmark. pernillemartens@yahoo.com BACKGROUND: Invasive infection...... with Streptococcus pneumoniae (pneumococci) causes significant morbidity and mortality. Case series and experimental data have shown that the capsular serotype is involved in the pathogenesis and a determinant of disease outcome. METHODS: Retrospective review of 464 cases of invasive disease among adults diagnosed...... with serotype 1 was associated with a decreased risk of death (RR 0.23 (95% CI, 0.06-0.97)). Additionally, older age, relative leucopenia and relative hypothermia were independent predictors of mortality. CONCLUSION: Our study shows that capsular serotypes independently influenced the outcome from invasive...

  1. Energy in synthetic fertilizers and pesticides: Revisited. Final project report

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, M.G.; English, B.C.; Turhollow, A.F.; Nyangito, H.O. [Tennessee Univ., Knoxville, TN (United States). Dept. of Agricultural Economics and Rural Sociology

    1994-01-01

    Agricultural chemicals that are derived from fossil-fuels are the major energy intensive inputs in agriculture. Growing scarcity of the world`s fossil resources stimulated research and development of energy-efficient technology for manufacturing these chemicals in the last decade. The purpose of this study is to revisit the energy requirements of major plant nutrients and pesticides. The data from manufacturers energy survey conducted by The Fertilizer Institute are used to estimate energy requirements of fertilizers. Energy estimates for pesticides are developed from consulting previously published literature. The impact of technical innovation in the fertilizer industry to US corn, cotton, soybean and wheat producers is estimated in terms of energy-saving.

  2. Global Instability on Laminar Separation Bubbles-Revisited

    Science.gov (United States)

    Theofilis, Vassilis; Rodriquez, Daniel; Smith, Douglas

    2010-01-01

    In the last 3 years, global linear instability of LSB has been revisited, using state-of-the-art hardware and algorithms. Eigenspectra of LSB flows have been understood and classified in branches of known and newly-discovered eigenmodes. Major achievements: World-largest numerical solutions of global eigenvalue problems are routinely performed. Key aerodynamic phenomena have been explained via critical point theory, applied to our global mode results. Theoretical foundation for control of LSB flows has been laid. Global mode of LSB at the origin of observable phenomena. U-separation on semi-infinite plate. Stall cells on (stalled) airfoil. Receptivity/Sensitivity/AFC feasible (practical?) via: Adjoint EVP solution. Direct/adjoint coupling (the Crete connection). Minor effect of compressibility on global instability in the subsonic compressible regime. Global instability analysis of LSB in realistic supersonic flows apparently quite some way down the horizon.

  3. Impulsive Spot Heating and Thermal Explosion of Interstellar Grains Revisited

    CERN Document Server

    Ivlev, A V; Vasyunin, A; Caselli, P

    2015-01-01

    The problem of impulsive heating of dust grains in cold, dense interstellar clouds is revisited theoretically, with the aim to better understand leading mechanisms of the explosive desorption of icy mantles. It is rigorously shown that if the heating of a reactive medium occurs within a sufficiently localized spot (e.g., heating of mantles by cosmic rays), then the subsequent thermal evolution is characterized by a single dimensionless number $\\lambda$. This number identifies a bifurcation between two distinct regimes: When $\\lambda$ exceeds a critical value (threshold), the heat equation exhibits the explosive solution, i.e., the thermal (chemical) explosion is triggered. Otherwise, thermal diffusion causes the deposited heat to spread over the entire grain -- this regime is commonly known as the whole-grain heating. The theory allows us to find a critical combination of the physical parameters that govern the explosion of icy mantles due to impulsive spot heating. In particular, the calculations suggest tha...

  4. Neuroticism and vigilance revisited: A transcranial doppler investigation.

    Science.gov (United States)

    Mandell, Arielle R; Becker, Alexandra; VanAndel, Aaron; Nelson, Andrew; Shaw, Tyler H

    2015-11-01

    Selecting for vigilance assignments remains an important factor in human performance research. The current study revisits the potential relationship between vigilance performance and trait neuroticism, in light of two possible theories. The first theory suggests that neuroticism impairs vigilance performance by competing for available resources. The second theory, attentional control theory, posits that high neuroticism can result in similar or superior performance levels due to the allocation of compensatory effort. In the present study, Transcranial Doppler Sonography was used to investigate the neurophysiological underpinnings of neuroticism during a 12-min abbreviated vigilance task. Performance results were not modified by level of neuroticism, but high neuroticism was associated with higher initial CBFV levels and a greater CBFV decrement over time. These findings indicate that participants higher in neuroticism recruited additional cognitive resources in order to achieve similar performance, suggesting that there is more of an effect on processing efficiency than effectiveness.

  5. Revisiting constraints on uplifts to de Sitter vacua

    CERN Document Server

    Bizet, Nana Cabo

    2016-01-01

    We revisit the issue of uplifting the potential to de Sitter (dS) vacua in type IIB flux compactifications of Kachru, Kallosh, Linde and Trivedi (KKLT). We shed light on some tension between two constraints on dS vacua in type IIB string theory. One is the well-known and much-discussed constraint which leads to the no-go theorem that can in principle be evaded. The other follows from 4-dimensional Einstein's equations, which has, however, been much less discussed in connection with the former constraint. In addition to the challenges previously posed, it is suggested that the uplifting scenarios, in particular, obstruct the evasion of the no-go theorem more strongly than one might have assumed.

  6. Revisiting time reversal and holography with spacetime transformations

    CERN Document Server

    Bacot, Vincent; Eddi, Antonin; Fink, Mathias; Fort, Emmanuel

    2015-01-01

    Wave control is usually performed by spatially engineering the properties of a medium. Because time and space play similar roles in wave propagation, manipulating time boundaries provides a complementary approach. Here, we experimentally demonstrate the relevance of this concept by introducing instantaneous time mirrors. We show with water waves that a sudden change of the effective gravity generates time-reversed waves that refocus at the source. We generalize this concept for all kinds of waves introducing a universal framework which explains the effect of any time disruption on wave propagation. We show that sudden changes of the medium properties generate instant wave sources that emerge instantaneously from the entire space at the time disruption. The time-reversed waves originate from these "Cauchy sources" which are the counterpart of Huygens virtual sources on a time boundary. It allows us to revisit the holographic method and introduce a new approach for wave control.

  7. Magnetic Field - Gas Density Relation and Observational Implications Revisited

    CERN Document Server

    Tritsis, A; Mouschovias, T Ch; Tassis, K; Pavlidou, V

    2015-01-01

    We revisit the relation between magnetic-field strength ($B$) and gas density ($\\rho$) for contracting interstellar clouds and fragments (or, cores), which is central in observationally determining the dynamical importance of magnetic fields in cloud evolution and star formation. Recently, it has been claimed that a relation $B \\propto \\rho^{2/3} $ is statistically preferred over $B \\propto \\rho^{1/2}$ in molecular clouds, when magnetic field detections and nondetections from Zeeman observations are combined. This finding has unique observational implications on cloud and core geometry: The relation $B \\propto \\rho^{2/3} $ can only be realized under spherical contraction. However, no indication of spherical geometry can be found for the objects used in the original statistical analysis of the $B-\\rho$ relation. We trace the origin of the inconsistency to simplifying assumptions in the statistical model used to arrive at the $B\\propto \\rho^{2/3}$ conclusion and to an underestimate of observational uncertaintie...

  8. Revisiting world energy intensity convergence for regional differences

    Energy Technology Data Exchange (ETDEWEB)

    Liddle, Brantley [Centre for Strategic Economic Studies, Victoria University, Melbourne, VIC 8001 (Australia)

    2010-10-15

    World convergence in energy intensity is revisited using two new large data sets: a 111-country sample spanning 1971-2006, and a 134-country sample spanning 1990-2006. Both data sets confirm continued convergence. However, the larger data set, which adds the former Soviet Union republics and additional Balkan countries, indicates greater convergence over its more recent time-frame. Further investigation of geographical differences reveals that the OECD and Eurasian countries have shown considerable, continued convergence, while the Sub-Saharan African countries have converged amongst themselves, but at a slower rate than the OECD and Eurasian countries; by contrast, Latin American and Caribbean and Middle East and North African countries have exhibited no convergence to divergence in energy intensity. (author)

  9. Revisiting the scattering greenhouse effect of CO2 ice clouds

    CERN Document Server

    Kitzmann, Daniel

    2016-01-01

    Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO2 dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.

  10. Simulation of Two-Way Pushdown Automata Revisited

    Directory of Open Access Journals (Sweden)

    Robert Glück

    2013-09-01

    Full Text Available The linear-time simulation of 2-way deterministic pushdown automata (2DPDA by the Cook and Jones constructions is revisited. Following the semantics-based approach by Jones, an interpreter is given which, when extended with random-access memory, performs a linear-time simulation of 2DPDA. The recursive interpreter works without the dump list of the original constructions, which makes Cook's insight into linear-time simulation of exponential-time automata more intuitive and the complexity argument clearer. The simulation is then extended to 2-way nondeterministic pushdown automata (2NPDA to provide for a cubic-time recognition of context-free languages. The time required to run the final construction depends on the degree of nondeterminism. The key mechanism that enables the polynomial-time simulations is the sharing of computations by memoization.

  11. Stimulated Brillouin scattering revisited: Strong coupling regime and Rabi splitting

    CERN Document Server

    Huy, Kien Phan; Tchahame, Joel Cabrel; Sylvestre, Thibaut

    2015-01-01

    Stimulated Brillouin scattering in optical waveguides is a fundamental interaction between light and acoustic waves mediated by electrostriction and photoelasticity. In this paper, we revisit the usual theory of this inelastic scattering process to get a joint system in which the acoustic wave is strongly coupled to the interference pattern between the optical waves. We show in particular that, when the optoacoustic coupling rate is comparable to the phonon damping rate, the system enters in the strong coupling regime, giving rise to avoided crossing of the dispersion curve and Rabi-like splitting. We further find that optoacoustic Rabi splitting could in principle be observed using backward stimulated Brillouin scattering in sub-wavelength diameter tapered optical fibers with moderate peak pump power.

  12. Response variance in functional maps: neural darwinism revisited.

    Science.gov (United States)

    Takahashi, Hirokazu; Yokota, Ryo; Kanzaki, Ryohei

    2013-01-01

    The mechanisms by which functional maps and map plasticity contribute to cortical computation remain controversial. Recent studies have revisited the theory of neural Darwinism to interpret the learning-induced map plasticity and neuronal heterogeneity observed in the cortex. Here, we hypothesize that the Darwinian principle provides a substrate to explain the relationship between neuron heterogeneity and cortical functional maps. We demonstrate in the rat auditory cortex that the degree of response variance is closely correlated with the size of its representational area. Further, we show that the response variance within a given population is altered through training. These results suggest that larger representational areas may help to accommodate heterogeneous populations of neurons. Thus, functional maps and map plasticity are likely to play essential roles in Darwinian computation, serving as effective, but not absolutely necessary, structures to generate diverse response properties within a neural population.

  13. Response variance in functional maps: neural darwinism revisited.

    Directory of Open Access Journals (Sweden)

    Hirokazu Takahashi

    Full Text Available The mechanisms by which functional maps and map plasticity contribute to cortical computation remain controversial. Recent studies have revisited the theory of neural Darwinism to interpret the learning-induced map plasticity and neuronal heterogeneity observed in the cortex. Here, we hypothesize that the Darwinian principle provides a substrate to explain the relationship between neuron heterogeneity and cortical functional maps. We demonstrate in the rat auditory cortex that the degree of response variance is closely correlated with the size of its representational area. Further, we show that the response variance within a given population is altered through training. These results suggest that larger representational areas may help to accommodate heterogeneous populations of neurons. Thus, functional maps and map plasticity are likely to play essential roles in Darwinian computation, serving as effective, but not absolutely necessary, structures to generate diverse response properties within a neural population.

  14. Revisiting symmetries of lattice fermions via spin-flavor representation

    CERN Document Server

    Kimura, Taro; Misumi, Tatsuhiro; Noumi, Toshifumi; Torii, Shingo; Aoki, Sinya

    2011-01-01

    Employing the spin-flavor representation, we unveil the structures of the doubler-mixing symmetries and the mechanisms of their spontaneous breakdown in four types of lattice fermion formulation. We first revisit the naive fermion with the vanishing bare mass $m$, and identify the generators of the symmetries which form U(4)$\\times$U(4). The strong-coupling analysis shows that it is broken to U(4) by chiral condensation. We apply the same procedure to the Wilson fermion, which possesses only the U(1) vector symmetry for general values of $m$. For a special value of $m$, however, there emerges an additional U(1) symmetry to be broken by pion condensation. We also explore two types of minimally-doubled fermion, and discover a similar kind of symmetry enhancement and its spontaneous breakdown.

  15. Theory of magnetohydrodynamic waves: The WKB approximation revisited

    International Nuclear Information System (INIS)

    Past treatments of the eikonal or WKB theory of the propagation of magnetohydrodynamics waves have assumed a strictly isentropic background. IF in fact there is a gradient in the background entropy, then in second order in the WKB ordering, adiabatic fluctuations (in the Lagrangian sense) are not strictly isentropic in the Eulerian sense. This means that in the second order of the WKB expansion, which determines the variation of wave amplitude along rays, the violation of isentropy must be accounted for. The present paper revisits the derivation of the WKB approximation for small-amplitude magnetohydrodynamic waves, allowing for possible spatial variation of the background entropy. The equation of variation of wave amplitude is rederived; it is a bilinear equation which, it turns out, can be recast in the action conservation form. It is shown that this action conservation equation is in fact equivalent to the action conservation law obtained from Lagrangian treatments

  16. Revisiting Johnson and Jackson boundary conditions for granular flows

    Energy Technology Data Exchange (ETDEWEB)

    Li, Tingwen; Benyahia, Sofiane

    2012-07-01

    In this article, we revisit Johnson and Jackson boundary conditions for granular flows. The oblique collision between a particle and a flat wall is analyzed by adopting the classic rigid-body theory and a more realistic semianalytical model. Based on the kinetic granular theory, the input parameter for the partial-slip boundary conditions, specularity coefficient, which is not measurable in experiments, is then interpreted as a function of the particle-wall restitution coefficient, the frictional coefficient, and the normalized slip velocity at the wall. An analytical expression for the specularity coefficient is suggested for a flat, frictional surface with a low frictional coefficient. The procedure for determining the specularity coefficient for a more general problem is outlined, and a working approximation is provided.

  17. Online haemodiafiltration: definition, dose quantification and safety revisited.

    Science.gov (United States)

    Tattersall, James E; Ward, Richard A

    2013-03-01

    The general objective assigned to the EUropean DIALlysis (EUDIAL) Working Group by the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) was to enhance the quality of dialysis therapies in Europe in the broadest possible sense. Given the increasing interest in convective therapies, the Working Group has started by focusing on haemodiafiltration (HDF) therapies. Several reports suggest that those therapies potentially improve the outcomes for end-stage renal disease patients. Europe is the leader in the field, having introduced the concept of ultra-purity for water and dialysis fluids and with notified bodies of the European Community having certified water treatment systems and online HDF machines. The prevalence of online HDF-treated patients is steadily increasing in Europe, averaging 15%. A EUDIAL consensus conference was held in Paris on 13 October 2011 to revisit terminology, safety and efficacy of online HDF. This is the first report of the expert group arising from that conference.

  18. Revisiting a Classic Study of the Molecular Clock.

    Science.gov (United States)

    Robinson, Lauren M; Boland, Joseph R; Braverman, John M

    2016-03-01

    A constant rate of molecular evolution among homologous proteins and across lineages is known as the molecular clock. This concept has been useful for estimating divergence times. Here, we revisit a study by Richard Dickerson (J Mol Evol 1:26-45, 1971), wherein he provided striking visual evidence for a constant rate of amino acid changes among various evolutionary branch points. Dickerson's study is commonly cited as support of the molecular clock and a figure from it is often reproduced in textbooks. Since its publication, however, there have been updates made to dates of common ancestors based on the fossil record that should be considered. Additionally, collecting the accession numbers and carefully outlining Dickerson's methods serves as a resource to students of the molecular clock hypothesis.

  19. PhotoPrev:Unifying Context and Content Cues to Enhance Personal Photo Revisitation

    Institute of Scientific and Technical Information of China (English)

    Li Jin; Gang-Li Liu; Liang Zhao; Ling Feng; Senior Member; IEEE

    2015-01-01

    Personal photo revisitation on smart phones is a common yet uneasy task for users due to the large volume of photos taken in daily life. Inspired by the human memory and its natural recall characteristics, we build a personal photo revisitation tool, PhotoPrev, to facilitate users to revisit previous photos through associated memory cues. To mimic users’ episodic memory recall, we present a way to automatically generate an abundance of related contextual metadata (e.g., weather, temperature) and organize them as context lattices for each photo in a life cycle. Meanwhile, photo content (e.g., object, text) is extracted and managed in a weighted term list, which corresponds to semantic memory. A threshold algorithm based photo revisitation framework for context-and content-based keyword search on a personal photo collection, together with a user feedback mechanism, is also given. We evaluate the scalability on a large synthetic dataset by crawling users’ photos from Flickr, and a 12-week user study demonstrates the feasibility and effectiveness of our photo revisitation strategies.

  20. 水中三氯甲烷、四氯化碳的QHSS -40自动进样顶空气相色谱测定法%Determination of chloroform and carbon tetrachloride in water by automatic headspace gas chromatography

    Institute of Scientific and Technical Information of China (English)

    罗黎明

    2012-01-01

    目的 建立测定水中三氯甲烷和四氯化碳含量的全自动顶空气相色谱法.方法 利用全自动顶空进样技术,采用ECD检测器测定水中三氯甲烷和四氯化碳.结果 在测定条件下,方法的检出限三氯甲烷为0.06 μg/L,四氯化碳为0.03μg/L;三氯甲烷的RSD为1.7% ~2.5%,四氯化碳的RSD为1.5~2.8%;回收率三氯甲烷为101%~103%,四氯化碳为99.6% ~ 102%.结论 该方法简便、快速、具有较好的精密度与准确度,适用于水中三氯甲烷、四氯化碳测定.%[ Objective] To establish the method for determination of chloroform and carbon tetrachloride in water by automatic head-space gas chromatography. [ Methods ] Automated headspace sampling technology was adopted to detect chloroform and carbon tetrachloride in drinking water with ECD detector. [Results] Under the determination conditions, the detection limit was 0.03μg / L of chloroform and 0.06 μg/ L of carbon tetrachloride; RSD of chloroform and carbon tetrachloride was 1.7-2.5% andl.5-2. 8% , respectively; recoveries of chloroform and carbon tetrachloride were 101%-103% and 99. 6% ~ 102% , respectively. [ Conclusion] This method is simple, rapid, with good precision and accuracy, and suitable for determination of chloroform and carbon tetrachloride in drinking water.

  1. Spectrophotometric study of interaction of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone with diaza-18-crown-6 and diaza-15-crown-5 in acetonitrile and chloroform solutions

    Science.gov (United States)

    Hasani, Masoumeh; Shamsipur, Mojtaba

    2005-03-01

    Interactions of diaza-18-crown-6 and diaza-15-crown-5, as electron donors, with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), as an electron acceptor, have been investigated spectrophotometrically in acetonitrile and chloroform solutions. The results indicated immediate formation of an electron donor-electron acceptor complex DA: D+A ⇌fastKDA which is followed by two relatively slow consecutive reactions: DA⟶kDA⟶kProduct The pseudo-first-order rate constants for the formation of the ionic intermediate and the final product have been evaluated at various temperatures by computer fitting of the absorbance time data to appropriate equations. The formation constants of the resulting DA complexes have also been determined. The influences of both the azacrown's structure and the solvent properties on the formation of DA complexes and the rates of subsequent reactions are discussed.

  2. 3,10,14,21-Tetrakis(4-methoxyphenylpentacyclo[11.8.0.02,11.04,9.015,20]henicosa-1(21,2,4(9,5,7,10,13,15(20,16,18-decaen-12-one chloroform monosolvate

    Directory of Open Access Journals (Sweden)

    S. Gopinath

    2014-08-01

    Full Text Available The asymmetric unit of the title compound, C49H36O6·CHCl3, contains half an organic molecule, the complete molecule being generated by the operation of a crystallographic twofold rotation axis, and half a highly disordered chloroform molecule. The contribution to the diffraction pattern of the latter was removed using the program SQUEEZE in PLATON [Spek (2009. Acta Cryst. D65, 148–155]; the unit-cell characteristics take into account the presence of CHCl3. The dihedral angles between the planes of the naphthalene ring system and the methoxybenzene rings are 71.05 (7 (syn to the central C=O group and 57.27 (6° (anti to the central C=O group. In the crystal, molecules are linked by C—H...O interactions, generating C(12 chains running parallel to the b axis.

  3. Dynamic and kinematic viscosities, excess volumes and excess Gibbs energies of activation for viscous flow in the ternary mixture {1- propanol+ N,N-dimethylformamide + chloroform} at temperatures between 293.15 K and 323.15 K

    Energy Technology Data Exchange (ETDEWEB)

    Hassein-bey-Larouci, A., E-mail: hasseinbey@yahoo.fr [Laboratoire Thermodynamique et Modélisation Moléculaire, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, B.P. 32, El-Alia, 16111 Bab-Ezzouar, Alger (Algeria); Igoujilen, O.; Aitkaci, A. [Laboratoire Thermodynamique et Modélisation Moléculaire, Faculté de Chimie, Université des Sciences et de la Technologie Houari Boumediene, B.P. 32, El-Alia, 16111 Bab-Ezzouar, Alger (Algeria); Segovia, J.J.; Villamañán, M.A. [TERMOCAL Research Group, Escuela de Ingenierías Industriales, Universidad de Valladolid, Paseo del Cauce, 59, 47011 Valladolid (Spain)

    2014-08-10

    Highlights: • Many engineering applications require quantitative thermodynamic data of the fluids. • Excess properties of mixtures are important in the understanding of mixing process. • The results are used to explain the molecular interaction in the mixtures. - Abstract: Dynamic and kinematic viscosities, and densities of the ternary mixture {x_1 propanol + x_2 DMF + x_3 chloroform} and of the three corresponding binary systems have been measured at 293.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The thermophysical properties, viscosity deviations (Δη), kinematic viscosity (γ), excess Gibbs energies of activation of viscous flow (G*{sup E}) and excess molar volumes (V{sup E}) have been calculated from experimental values of dynamic viscosity, η, and density, ρ. The different results have been correlated by the Redlich–Kister equation for the binary mixtures and the Cibulka equation for equation for the ternary ones.

  4. Yolk antibody were extracted in eggs by Chloroform methods, hydrolysis methods and carrageenan methods%氯仿法、水解法、卡拉胶法提取鸡蛋中卵黄抗体

    Institute of Scientific and Technical Information of China (English)

    杨波; 霍乃蕊

    2013-01-01

    卵黄抗体(egg-yolk antibody,IgY)具有一些IgG所没有的优良特性,与哺乳动物的IgG相比,IgY的提取具有方法简单,提取率高且方法多样等优点.本文旨在对当前条件下卵黄抗体的提取方法进行比较.选取水溶法(Water Dilution,WD)、氯仿法(Chloroform,CHL)和卡拉胶法(Carrageenan,CAR)制备IgY,根据电泳结果,比较三种方法得率高低.SDS-PAGE结果表明,氯仿法的得率较其他两种方法高一些.

  5. Dynamic and kinematic viscosities, excess volumes and excess Gibbs energies of activation for viscous flow in the ternary mixture {1- propanol+ N,N-dimethylformamide + chloroform} at temperatures between 293.15 K and 323.15 K

    International Nuclear Information System (INIS)

    Highlights: • Many engineering applications require quantitative thermodynamic data of the fluids. • Excess properties of mixtures are important in the understanding of mixing process. • The results are used to explain the molecular interaction in the mixtures. - Abstract: Dynamic and kinematic viscosities, and densities of the ternary mixture {x1 propanol + x2 DMF + x3 chloroform} and of the three corresponding binary systems have been measured at 293.15, 303.15, 313.15 and 323.15 K and atmospheric pressure. The thermophysical properties, viscosity deviations (Δη), kinematic viscosity (γ), excess Gibbs energies of activation of viscous flow (G*E) and excess molar volumes (VE) have been calculated from experimental values of dynamic viscosity, η, and density, ρ. The different results have been correlated by the Redlich–Kister equation for the binary mixtures and the Cibulka equation for equation for the ternary ones

  6. Changes in Sea Levels around the British Isles Revisited (Invited)

    Science.gov (United States)

    Teferle, F. N.; Hansen, D. N.; Bingley, R. M.; Williams, S. D.; Woodworth, P. L.; Gehrels, W. R.; Bradley, S. L.; Stocchi, P.

    2009-12-01

    Recently a number of new and/or updated sources for estimates of vertical land movements for the British Isles have become available allowing the relative and average changes in sea levels for this region to be revisited. The geodetic data set stems from a combination of re-processed continuous Global Positioning System (GPS) measurements from stations in the British Isles and from a global reference frame network, and absolute gravity (AG) measurements from two stations in the British Isles. The geologic data set of late Holocene sea level indicators has recently been updated, now applying corrections for the 20th century sea level rise, syphoning effect and late Holocene global ice melt, and expanded to Northern Ireland and Ireland. Several new model predictions of the glacial isostatic adjustment (GIA) process active in this region form the modelling data set of vertical land movements for the British Isles. Correcting the updated revised local reference (RLR) trends from the Permanent Service for Mean Sea Level (PSMSL) with these vertical land movement data sets, regional and averaged changes in sea levels around the British Isles have been investigated. Special focus is thereby also given to the coastal areas that have recently been identified within the UK Climate Projections 2009.

  7. The interaction of atoms with LiF(001) revisited

    CERN Document Server

    Miraglia, J E

    2016-01-01

    Pairwise additive potentials for multielectronic atoms interacting with a LiF(001) surface are revisited by including an improved description of the electron density associated with the different lattice sites, as well as non-local electron density contributions. Within this model, the electron distribution around each ionic site of the crystal is described by means of an onion approach that accounts for the influence of the Madelung potential. From such densities, binary interatomic potentials are then derived by using well-known non-local functionals for the kinetic, exchange and correlation terms. Rumpling and long-range contributions due to projectile polarization and van der Waals forces are also included in an analogous fashion. We apply this pairwise additive approximation to evaluate the interaction potential between closed-shell - He, Ne, Ar, Kr, and Xe - and open-shell - N, S, and Cl - atoms and the LiF surface, analyzing the relative importance of the different contributions. The performance of the...

  8. Whistler oscillitons revisited: the role of charge neutrality?

    Directory of Open Access Journals (Sweden)

    F. Verheest

    2004-01-01

    Full Text Available When studying transverse modes propagating parallel to a static magnetic field, an apparent contradiction arises between the weakly nonlinear results obtained from the derivative nonlinear Schrödinger equation, predicting envelope solitons (where the amplitude is stationary in the wave frame, but the phase is not, and recent results for whistler oscillitons, indicating that really stationary structures of large amplitude are possible. Revisiting this problem in the fluid dynamic approach, care has been taken not to introduce charge neutrality from the outset, because this not only neglects electric stresses compared to magnetic stresses, which is reasonable, but could also imply from Poisson's equation a vanishing of the wave electric field. Nevertheless, the fixed points of the remaining equations are the same, whether charge neutrality is assumed from the outset or not, so that the solitary wave solutions at not too large amplitudes will be very similar. This is borne out by numerical simulations of the solutions under the two hypotheses, showing that the lack of correspondence with the DNLS envelope solitons indicates the limitations of the reductive perturbation approach, and is not a consequence of assuming charge neutrality.

  9. Revisiting the Master-Signifier, or, Mandela and Repression.

    Science.gov (United States)

    Hook, Derek; Vanheule, Stijn

    2015-01-01

    The concept of the master-signifier has been subject to a variety of applications in Lacanian forms of political discourse theory and ideology critique. While there is much to be commended in literature of this sort, it often neglects salient issues pertaining to the role of master signifiers in the clinical domain of (individual) psychical economy. The popularity of the concept of the master (or "empty") signifier in political discourse analysis has thus proved a double-edged sword. On the one hand it demonstrates how crucial psychical processes are performed via the operations of the signifier, extending thus the Lacanian thesis that identification is the outcome of linguistic and symbolic as opposed to merely psychological processes. On the other, the use of the master signifier concept within the political realm to track discursive formations tends to distance the term from the dynamics of the unconscious and operation of repression. Accordingly, this paper revisits the master signifier concept, and does so within the socio-political domain, yet while paying particular attention to the functioning of unconscious processes of fantasy and repression. More specifically, it investigates how Nelson Mandela operates as a master signifier in contemporary South Africa, as a vital means of knitting together diverse elements of post-apartheid society, enabling the fantasy of the post-apartheid nation, and holding at bay a whole series of repressed and negated undercurrents. PMID:26834664

  10. Revisiting the master-signifier, or, Mandela and repression

    Directory of Open Access Journals (Sweden)

    Derek eHook

    2016-01-01

    Full Text Available The concept of the master-signifier has been subject to a variety of applications in Lacanian forms of political discourse theory and ideology critique. While there is much to be commended in literature of this sort, it often neglects salient issues pertaining to the role of master signifiers in the clinical domain of (individual psychical economy. The popularity of the concept of the master (or ‘empty’ signifier in political discourse analysis has thus proved a double-edged sword. On the one hand it demonstrates how crucial psychical processes are performed via the operations of the signifier, extending thus the Lacanian thesis that identification is as much the outcome of linguistic and symbolic as opposed to merely psychological processes. On the other, the use of the master signifier concept within the political realm to track discursive formations tends to distance the term from the dynamics of the unconscious and operation of repression. Accordingly, this paper revisits the master signifier concept, and does so within the socio-political domain, yet while paying particular attention to the functioning of unconscious processes of fantasy and repression. More specifically, it investigates how Nelson Mandela operates as a master signifier in contemporary South Africa, as a vital means of knitting together diverse elements of post-apartheid society, enabling the fantasy of the post-apartheid nation, and holding at bay a whole series of repressed and negated undercurrents.

  11. Revisiting the Master-Signifier, or, Mandela and Repression

    Science.gov (United States)

    Hook, Derek; Vanheule, Stijn

    2016-01-01

    The concept of the master-signifier has been subject to a variety of applications in Lacanian forms of political discourse theory and ideology critique. While there is much to be commended in literature of this sort, it often neglects salient issues pertaining to the role of master signifiers in the clinical domain of (individual) psychical economy. The popularity of the concept of the master (or “empty”) signifier in political discourse analysis has thus proved a double-edged sword. On the one hand it demonstrates how crucial psychical processes are performed via the operations of the signifier, extending thus the Lacanian thesis that identification is the outcome of linguistic and symbolic as opposed to merely psychological processes. On the other, the use of the master signifier concept within the political realm to track discursive formations tends to distance the term from the dynamics of the unconscious and operation of repression. Accordingly, this paper revisits the master signifier concept, and does so within the socio-political domain, yet while paying particular attention to the functioning of unconscious processes of fantasy and repression. More specifically, it investigates how Nelson Mandela operates as a master signifier in contemporary South Africa, as a vital means of knitting together diverse elements of post-apartheid society, enabling the fantasy of the post-apartheid nation, and holding at bay a whole series of repressed and negated undercurrents. PMID:26834664

  12. Revisiting Link Prediction: Evolving Models and Real Data Findings

    CERN Document Server

    Mendoza, Marcelo

    2016-01-01

    The explosive growth of Web 2.0, which was characterized by the creation of online social networks, has reignited the study of factors that could help us understand the growth and dynamism of these networks. Various generative network models have been proposed, including the Barabasi-Albert and Watts-Strogatz models. In this study, we revisit the problem from a perspective that seeks to compare results obtained from these generative models with those from real networks. To this end, we consider the dating network Skout Inc. An analysis is performed on the topological characteristics of the network that could explain the creation of new network links. Afterwards, the results are contrasted with those obtained from the Barabasi-Albert and Watts-Strogatz generative models. We conclude that a key factor that could explain the creation of links originates in its cluster structure, where link recommendations are more precise in Watts-Strogatz segmented networks than in Barabasi-Albert hierarchical networks. This re...

  13. Revisiting scaling relations for giant radio halos in galaxy clusters

    CERN Document Server

    Cassano, R; Brunetti, G; Giacintucci, S; Pratt, G W; Venturi, T; Kale, R; Dolag, K; Markevitch, M

    2013-01-01

    Many galaxy clusters host Megaparsec-scale radio halos, generated by ultrarelativistic electrons in the magnetized intracluster medium. Correlations between the power of radio halos and the thermal properties of the hosting clusters were established in the last decade, including the connection between the presence of a halo and cluster mergers. The X-ray luminosity and redshift limited Extended GMRT Radio Halo Survey provides a rich and unique dataset for statistical studies of the halos. We uniformly analyze the radio and X-ray data for the GMRT cluster sample, and use the new Planck SZ catalog, to revisit the correlations between the power of halos and the thermal properties of galaxy clusters. We find that the radio power of halos at 1.4 GHz scales with the cluster X-ray (0.1--2.4 keV) luminosity computed within R_500 as P_1.4 L_500^2.0. Our bigger and more homogenous sample confirms that the X-ray luminous (L_500 > 5x10^44 erg/s) clusters branch into two populations --- radio halos lie on the correlation,...

  14. Finite size effect on classical ideal gas revisited

    Science.gov (United States)

    Ghosh, P.; Ghosh, S.; Mitra, J.; Bera, N.

    2015-09-01

    Finite size effects on classical ideal gas are revisited. The micro-canonical partition function for a collection of ideal particles confined in a box is evaluated using Euler-Maclaurin’s as well as Poisson's summation formula. In Poisson's summation formula there are some exponential terms which are absent in Euler-Maclaurin’s formula. In the thermodynamic limit the exponential correction is negligibly small but in the macro/nano dimensions and at low temperatures they may have a great significance. The consequences of finite size effects have been illustrated by redoing the calculations in one and three dimensions keeping the exponential corrections. Global and local thermodynamic properties, diffusion driven by the finite size effect, and effect on speed of sound have been discussed. Thermo-size effects, similar to thermoelectric effects, have been described in detail and may be a theoretical basis with which to design nano-scaled devices. This paper can also be very helpful for undergraduate and graduate students in physics and chemistry as an instructive exercise for a good course in statistical mechanics.

  15. Revisiting the Source Process of the 2007 Tocopilla, Chile Earthquake

    Science.gov (United States)

    Simons, M.; Minson, S. E.; Jolivet, R.; Jiang, J.; Beck, J. L.

    2013-12-01

    We revisit the 2007 Mw 7.7 Tocopilla, Chile earthquake to create a finite fault kinematic source model based on the current best practices in data analysis and inversion methods. The data used to constrain the source model include both static GPS offsets and 1 Hz kinematic GPS time series, as well as interferograms which have been reanalyzed to remove tropospheric effects which can be quite significant in this region. Our inversion methodology is a Bayesian approach that uses only physics-based constraints on the rupture evolution, and which utilizes models of both the observational noise and the errors in our forward model to obtain the ensemble of all plausible rupture models which satisfy both the data and our a priori assumptions. This approach allows us to better understand which parts of the rupture process are well-constrained and which are not, and thus to better understand how the 2007 Tocopilla, Chile earthquake rupture fits into the sequence of large earthquakes which have been mosaicking the northern Chile subduction zone.

  16. Photoevaporation of Circumstellar Disks Revisited: The Dust-Free Case

    CERN Document Server

    Tanaka, Kei E I; Omukai, Kazuyuki

    2013-01-01

    Photoevaporation by stellar ionizing radiation is believed to play an important role in the dispersal of disks around young stars. The mass loss model for dust-free disks developed by Hollenbach et al. is currently regarded as a conventional one and has been used in a wide variety of studies. However, the rate in this model was derived by the crude so-called 1+1D approximation of ionizing radiation transfer, which assumes that diffuse radiation propagates in a direction vertical to the disk. In this study, we revisit the photoevaporation of dust-free disks by solving the 2D axisymmetric radiative transfer for steady-state disks. Unlike that solved by the conventional model, we determine that direct stellar radiation is more important than the diffuse field at the disk surface. The radial density distribution at the ionization boundary is represented by the single power-law with an index -3/2 in contrast to the conventional double power-law. For this distribution, the photoevaporation rate from the entire disk...

  17. The Mantel-Haenszel procedure revisited: models and generalizations.

    Directory of Open Access Journals (Sweden)

    Vaclav Fidler

    Full Text Available Several statistical methods have been developed for adjusting the Odds Ratio of the relation between two dichotomous variables X and Y for some confounders Z. With the exception of the Mantel-Haenszel method, commonly used methods, notably binary logistic regression, are not symmetrical in X and Y. The classical Mantel-Haenszel method however only works for confounders with a limited number of discrete strata, which limits its utility, and appears to have no basis in statistical models. Here we revisit the Mantel-Haenszel method and propose an extension to continuous and vector valued Z. The idea is to replace the observed cell entries in strata of the Mantel-Haenszel procedure by subject specific classification probabilities for the four possible values of (X,Y predicted by a suitable statistical model. For situations where X and Y can be treated symmetrically we propose and explore the multinomial logistic model. Under the homogeneity hypothesis, which states that the odds ratio does not depend on Z, the logarithm of the odds ratio estimator can be expressed as a simple linear combination of three parameters of this model. Methods for testing the homogeneity hypothesis are proposed. The relationship between this method and binary logistic regression is explored. A numerical example using survey data is presented.

  18. The Mantel-Haenszel procedure revisited: models and generalizations.

    Science.gov (United States)

    Fidler, Vaclav; Nagelkerke, Nico

    2013-01-01

    Several statistical methods have been developed for adjusting the Odds Ratio of the relation between two dichotomous variables X and Y for some confounders Z. With the exception of the Mantel-Haenszel method, commonly used methods, notably binary logistic regression, are not symmetrical in X and Y. The classical Mantel-Haenszel method however only works for confounders with a limited number of discrete strata, which limits its utility, and appears to have no basis in statistical models. Here we revisit the Mantel-Haenszel method and propose an extension to continuous and vector valued Z. The idea is to replace the observed cell entries in strata of the Mantel-Haenszel procedure by subject specific classification probabilities for the four possible values of (X,Y) predicted by a suitable statistical model. For situations where X and Y can be treated symmetrically we propose and explore the multinomial logistic model. Under the homogeneity hypothesis, which states that the odds ratio does not depend on Z, the logarithm of the odds ratio estimator can be expressed as a simple linear combination of three parameters of this model. Methods for testing the homogeneity hypothesis are proposed. The relationship between this method and binary logistic regression is explored. A numerical example using survey data is presented. PMID:23516463

  19. An Adaptive and Hybrid Approach for Revisiting the Visibility Pipeline

    Directory of Open Access Journals (Sweden)

    Ícaro Lins Leitão da Cunha

    2016-04-01

    Full Text Available We revisit the visibility problem, which is traditionally known in Computer Graphics and Vision fields as the process of computing a (potentially visible set of primitives in the computational model of a scene. We propose a hybrid solution that uses a dry structure (in the sense of data reduction, a triangulation of the type J1a, to accelerate the task of searching for visible primitives. We came up with a solution that is useful for real-time, on-line, interactive applications as 3D visualization. In such applications the main goal is to load the minimum amount of primitives from the scene during the rendering stage, as possible. For this purpose, our algorithm executes the culling by using a hybrid paradigm based on viewing-frustum, back-face culling and occlusion models. Results have shown substantial improvement over these traditional approaches if applied separately. This novel approach can be used in devices with no dedicated processors or with low processing power, as cell phones or embedded displays, or to visualize data through the Internet, as in virtual museums applications.

  20. Large-scale filamentary structures around the Virgo cluster revisited

    CERN Document Server

    Kim, Suk; Bureau, Martin; Yoon, Hyein; Chung, Aeree; Jerjen, Helmut; Lisker, Thorsten; Jeong, Hyunjin; Sung, Eon-Chang; Lee, Youngdae; Lee, Woong; Chung, Jiwon

    2016-01-01

    We revisit the filamentary structures of galaxies around the Virgo cluster, exploiting a larger dataset based on the HyperLeda database than previous studies. In particular, this includes a large number of low-luminosity galaxies, resulting in better sampled individual structures. We confirm seven known structures in the distance range 4~$h^{-1}$~Mpc~$<$ SGY~$<$ 16~$h^{-1}$ Mpc, now identified as filaments, where SGY is the axis of the supergalactic coordinate system roughly along the line of sight. The Hubble diagram of the filament galaxies suggests they are infalling toward the main-body of the Virgo cluster. We propose that the collinear distribution of giant elliptical galaxies along the fundamental axis of the Virgo cluster is smoothly connected to two of these filaments (Leo~II~A and B). Behind the Virgo cluster (16~$h^{-1}$~Mpc~$<$ SGY~$<$ 27~$h^{-1}$~Mpc), we also identify a new filament elongated toward the NGC 5353/4 group ("NGC 5353/4 filament") and confirm a sheet that includes galaxi...

  1. A PROPOSAL FOR REVISITING FOOTWEAR TRADITION FOR INNOVATION

    Directory of Open Access Journals (Sweden)

    Mehmet Şahin

    2011-01-01

    Full Text Available Footwear has evolved from ancient times and through the centuries from protective sandals to a protective and aesthetic part of clothing. Today, there are many varieties of styles and materials used in the shoe industry. It is also noteworthy that some old fashions repeat themselves with only minor changes. It is a fact thatsome of the world’s most famous and popular companies have achieved that fame from cloth and footwear fashion and design. Tradition and culture have a huge impact on footwear design and on the motives and modes of how people buy and wear footwear. Therefore, tradition and culture of specific nation or region can create very important role at creating brand identities of European footwear companies. The aim of this paper is to present a Development of Innovation project proposal regarding revisiting traditional footwear so as to adapt itto up-to-date footwear training curriculum and production. The proposal aims to rediscover the peculiarities of traditional footwear and originality of cultural heritage of specific regions in order to transfer their design and models into VET curriculum so as to revive the traditions to create innovative products.

  2. Fever tree revisited: From malaria to autoinflammatory diseases.

    Science.gov (United States)

    Pastore, Serena; Vuch, Josef; Bianco, Anna Monica; Taddio, Andrea; Tommasini, Alberto

    2015-11-01

    Over the centuries the idea of recurrent fevers has mainly been associated with malaria, but many other fevers, such as typhoid and diphtheria were cause for concern. It is only in recent times, with the more severe forms of fever from infectious origin becoming less frequent or a cause for worry that we started noticing recurrent fevers without any clear infectious cause, being described as having a pathogenesis of autoinflammatory nature. The use of molecular examinations in many cases can allow a diagnosis where the cause is monogenic. In other cases, however the pathogenesis is likely to be multifactorial and the diagnostic-therapeutic approach is strictly clinical. The old fever tree paradigm developed to describe fevers caused by malaria has been revisited here to describe today's periodic fevers from the periodic fever adenitis pharyngitis aphthae syndrome to the more rare autoinflammatory diseases. This model may allow us to place cases that are yet to be identified which are likely to be of multifactorial origin. PMID:26566482

  3. Revisiting the OH-CH correlation in diffuse clouds

    CERN Document Server

    Mookerjea, Bhaswati

    2016-01-01

    Based on the analysis of available published data and archival data along 24 sightlines (5 of which are new) we derive more accurate estimates of the column densities of OH and CH towards diffuse/translucent clouds and revisit the typically observed correlation between the abundances of these species. The increase in the sample size was possible because of the equivalence of the column densities of CH derived from a combination of the transitions at 3137 & 3143 Angstrom, and a combination of transitions at 3886 & 3890 Angstrom, which we have demonstrated here. We find that with the exception of four diffuse clouds, the entire source sample shows a clear correlation between the column densities of OH and CH similar to previous observations. The analysis presented also verifies the theoretically predicted oscillator strengths of the OH A--X (3078 & 3082 Angstrom), CH B--X (3886 & 3890 Angstrom) and C--X (3137 & 3143 Angstrom) transitions. We estimate N(H) and N(H2) from the observed E(B-V) a...

  4. The angular momentum of baryons and dark matter halos revisited

    CERN Document Server

    Kimm, Taysun; Slyz, Adrianne; Pichon, Christophe; Kassin, Susan A; Dubois, Yohan

    2011-01-01

    Recent theoretical studies have shown that galaxies at high redshift are fed by cold, dense gas filaments, suggesting angular momentum transport by gas differs from that by dark matter. Revisiting this issue using high-resolution cosmological hydrodynamics simulations with adaptive mesh refinement, we find that at the time of accretion, gas and dark matter do carry a similar amount of specific angular momentum, but that it is systematically higher than that of the dark matter halo as a whole. At high redshift, freshly accreted gas rapidly streams into the central region of the halo, directly depositing this large amount of angular momentum within a sphere of radius r=0.1rvir. In contrast, dark matter particles pass through the central region unscathed, and a fraction of them ends up populating the outer regions of the halo (r/rvir>0.1), redistributing angular momentum in the process. As a result, large-scale motions of the cosmic web have to be considered as the origin of gas angular momentum rather than its ...

  5. ISLAM, ADAT, AND THE STATE: Matrifocality in Aceh Revisited

    Directory of Open Access Journals (Sweden)

    Eka Srimulyani

    2010-08-01

    Full Text Available Matrifocality has been a rooted tradition in the social history of the community in Aceh. The principles of matrifocality have also affected on how women are positioned in the community, and the socio-gender relation within the community. The fact that Aceh has strongly associated to the Islamic values that claimed to support the paternal traditions. Apparently, the Islamic values and the local matrifocality practices juxtaposed through the roles of adat, which considered as inseparable to Islamic law or teaching, or in local term known as zat ngeun sifeut. Another point in revisiting matrifocality in Aceh in Aceh is an examination of how gender state ideology, particularly during the New Order Regime disregarded some local gender practices across some ethnics in the archipelago. Meanwhile, the state also hegemonied and promoted particular gender state ideology such as state ibuism. Nonetheless, the modernity and social changes have also contributed to the shifting of some matrifocality practices in contemporary Acehnese society. However, since the matrifocality has a strong root in the social life of the community, the principles of the matrifocality still survived until currently, although it transformed into ‘new matrifocality’ practices. Keywords: matrifocality, Aceh, gender, shari‘a law

  6. Biogas from Macroalgae: is it time to revisit the idea?

    Directory of Open Access Journals (Sweden)

    Hughes Adam D

    2012-11-01

    Full Text Available Abstract The economic and environmental viability of dedicated terrestrial energy crops is in doubt. The production of large scale biomass (macroalgae for biofuels in the marine environment was first tested in the late 1960’s. The culture attempts failed due to the engineering challenges of farming offshore. However the energy conversion via anaerobic digestion was successful as the biochemical composition of macroalgae makes it an ideal feedstock. The technology for the mass production of macroalgae has developed principally in China and Asia over the last 50 years to such a degree that it is now the single largest product of aquaculture. There has also been significant technology transfer and macroalgal cultivation is now well tried and tested in Europe and America. The inherent advantage of production of biofuel feedstock in the marine environment is that it does not compete with food production for land or fresh water. Here we revisit the idea of the large scale cultivation of macroalgae at sea for subsequent anaerobic digestion to produce biogas as a source of renewable energy, using a European case study as an example.

  7. Interplant volatile signaling in willows: revisiting the original talking trees.

    Science.gov (United States)

    Pearse, Ian S; Hughes, Kathy; Shiojiri, Kaori; Ishizaki, Satomi; Karban, Richard

    2013-07-01

    The importance of interplant volatile signaling in plant-herbivore interactions has been a contentious issue for the past 30 years. We revisit willows as the system in which evidence for interplant signaling was originally found, but then questioned. We established three well-replicated experiments with two willow species (Salix exigua and Salix lemmonii) to address whether the receipt of an interplant signal from a neighboring willow reduces herbivore damage. Additionally we tested whether this signal is volatile in nature, and whether plants signal better to themselves than they do to other individuals. In all three experiments, we found evidence that cues from a damaged neighbor reduce subsequent herbivory experienced by willows. In one experiment, we showed that bagging of clipped tissue, which prevents the exchange of volatile signals, removed the effect of neighbor wounding. This was consistent with results from the other two experiments, in which clipping potted neighbors connected only through airborne volatile cues reduced damage of receivers. In one year, we found evidence that the perception of volatile signals from genetically identical clones was more effective at reducing foliar damage to a neighbor than signals from a genetically different individual. However, this trend was not significant in the following year. In three well-replicated experiments, we found strong evidence for the importance of interplant volatile cues in mediating herbivore interactions with willows. PMID:23576105

  8. Leber′s hereditary optic neuropathy: The mitochondrial connection revisited

    Directory of Open Access Journals (Sweden)

    Khaled K Abu-Amero

    2011-01-01

    Full Text Available Our current understanding of Leber′s hereditary optic neuropathy (LHON-mitochondrial connection falls short of comprehensive. Twenty years of intensive investigation have yielded a wealth of information about mitochondria, the mitochondrial genome, the metabolism of the optic nerve and other structures, and the phenotypic variability of classic LHON. However, we still cannot completely explain how primary LHON mutations injure the optic nerve or why the optic nerve is particularly at risk. We cannot explain the incomplete penetrance or the male predominance of LHON, the typical onset in young adult life without warning, or the synchronicity of visual loss. Moreover, primary LHON mutations clearly are not present in every family with the LHON phenotype (including multigenerational maternal inheritance, and they are present in only a minority of individuals who have the LHON optic neuropathy phenotype without a family history. All lines of evidence point to abnormalities of the mitochondria as the direct or indirect cause of LHON. Therefore, the mitochondria-LHON connection needs to be revisited and examined closely. This review will attempt to do that and provide an update on various aspects of LHON.

  9. Leber's Hereditary Optic Neuropathy: The Mitochondrial Connection Revisited.

    Science.gov (United States)

    Abu-Amero, Khaled K

    2011-01-01

    Our current understanding of Leber's hereditary optic neuropathy (LHON)-mitochondrial connection falls short of comprehensive. Twenty years of intensive investigation have yielded a wealth of information about mitochondria, the mitochondrial genome, the metabolism of the optic nerve and other structures, and the phenotypic variability of classic LHON. However, we still cannot completely explain how primary LHON mutations injure the optic nerve or why the optic nerve is particularly at risk. We cannot explain the incomplete penetrance or the male predominance of LHON, the typical onset in young adult life without warning, or the synchronicity of visual loss. Moreover, primary LHON mutations clearly are not present in every family with the LHON phenotype (including multigenerational maternal inheritance), and they are present in only a minority of individuals who have the LHON optic neuropathy phenotype without a family history. All lines of evidence point to abnormalities of the mitochondria as the direct or indirect cause of LHON. Therefore, the mitochondria-LHON connection needs to be revisited and examined closely. This review will attempt to do that and provide an update on various aspects of LHON.

  10. Revisiting Cosmic No-Hair Theorem for Inflationary Settings

    CERN Document Server

    Maleknejad, A

    2012-01-01

    In this work we revisit Wald's cosmic no-hair theorem in the context of accelerating Bianchi cosmologies for a generic cosmic fluid with non-vanishing anisotropic stress tensor and when the fluid energy momentum tensor is of the form of a cosmological constant term plus a piece which does not respect strong or dominant energy conditions. Such a fluid is the one appearing in inflationary models. We show that for such a system anisotropy may grow, in contrast to the cosmic no-hair conjecture. In particular, for a generic inflationary model we show that there is an upper bound on the growth of anisotropy. For slow-roll inflationary models our analysis can be refined further and the upper bound is found to be of the order of slow-roll parameters. We examine our general discussions and our extension of Wald's theorem for three classes of slow-roll inflationary models, generic multi-scalar field driven models, anisotropic models involving U(1) gauge fields and the gauge-flation scenario.

  11. Revisiting reflexology: Concept, evidence, current practice, and practitioner training.

    Science.gov (United States)

    Embong, Nurul Haswani; Soh, Yee Chang; Ming, Long Chiau; Wong, Tin Wui

    2015-10-01

    Reflexology is basically a study of how one part of the human body relates to another part of the body. Reflexology practitioners rely on the reflexes map of the feet and hands to all the internal organs and other human body parts. They believe that by applying the appropriate pressure and massage certain spots on the feet and hands, all other body parts could be energized and rejuvenated. This review aimed to revisit the concept of reflexology and examine its effectiveness, practices, and the training for reflexology practitioners. PubMed, SCOPUS, Google Scholar, and SpringerLink databases were utilized to search the following medical subject headings or keywords: foot massage, reflexology, foot reflexotherapy, reflexological treatment, and zone therapy. The articles published for the last 10 years were included. Previous systematic reviews failed to show concrete evidence for any specific effect of reflexology in any conditions. Due to its non-invasive, non-pharmacological complementary nature, reflexology is widely accepted and anecdotal evidence of positive effect reflexology in a variety of health conditions are available. Adequate training for practitioners is necessary to ensure the consistency of service provided. PMID:26587391

  12. SUSY effects in Rb: Revisited under current experimental constraints

    Science.gov (United States)

    Su, Wei; Yang, Jin Min

    2016-06-01

    In this note we revisit the SUSY effects in Rb under current experimental constraints including the LHC Higgs data, the B-physics measurements, the dark matter relic density and direct detection limits, as well as the precision electroweak data. We first perform a scan to figure out the currently allowed parameter space and then display the SUSY effects in Rb. We find that although the SUSY parameter space has been severely restrained by current experimental data, both the general MSSM and the natural-SUSY scenario can still alter Rb with a magnitude sizable enough to be observed at future Z-factories (ILC, CEPC, FCC-ee, Super Z-factory) which produce 109-1012Z-bosons. To be specific, assuming a precise measurement δRb = 2.0 ×10-5 at FCC-ee, we can probe a right-handed stop up to 530 GeV through chargino-stop loops, probe a sbottom to 850 GeV through neutralino-sbottom loops and a charged Higgs to 770 GeV through the Higgs-top quark loops for a large tan ⁡ β. The full one-loop SUSY correction to Rb can reach 1 ×10-4 in natural SUSY and 2 ×10-4 in the general MSSM.

  13. Revisiting Discrete Dark Matter Model:\\theta_{13}\

    CERN Document Server

    Hamada, Yuta; Ogasahara, Atsushi; Omura, Yuji; Takayama, Fumihiro; Yasuhara, Daiki

    2014-01-01

    We revisit the discrete dark matter model with $A_4$ flavor symmetry originally introduced by M.Hirsch {\\it et.al}. We show that radiative corrections can lead to non-zero $\\theta_{13}$ and non-zero mass for the lightest neutrino. We find an interesting relation among neutrino mixing parameters and it indicates the sizable deviation of $s_{23}$ from the maximal angle $s_{23}^2=1/2$ and the degenerate mass spectrum for neutrinos. Also we study the possibilities that the right-handed neutrino is a dark matter candidate. Assuming the thermal freeze-out explains observed dark matter abundance, TeV-scale right-handed neutrino and flavored scalar bosons are required. In such a case, flavor symmetry plays an important role for the suppression of lepton flavor violating processes as well as for the stability of dark matter. We show that this scenario can be viable against currently existing constraints from collider, low energy experiments and cosmological observations.

  14. Revisiting Interpretation of Canonical Correlation Analysis: A Tutorial and Demonstration of Canonical Commonality Analysis

    Science.gov (United States)

    Nimon, Kim; Henson, Robin K.; Gates, Michael S.

    2010-01-01

    In the face of multicollinearity, researchers face challenges interpreting canonical correlation analysis (CCA) results. Although standardized function and structure coefficients provide insight into the canonical variates produced, they fall short when researchers want to fully report canonical effects. This article revisits the interpretation of…

  15. Resampling Methods Revisited: Advancing the Understanding and Applications in Educational Research

    Science.gov (United States)

    Bai, Haiyan; Pan, Wei

    2008-01-01

    Resampling methods including randomization test, cross-validation, the jackknife and the bootstrap are widely employed in the research areas of natural science, engineering and medicine, but they lack appreciation in educational research. The purpose of the present review is to revisit and highlight the key principles and developments of…

  16. Re-Visit to the School Nurse and Adolescents' Medicine Use

    Science.gov (United States)

    Borup, Ina K.; Andersen, Anette; Holstein, Bjorn E.

    2011-01-01

    Objective: To examine if students who re-visit the school nurse use medicines differently than other students when exposed to aches and psychological problems. Methods: The study includes all 11-, 13- and 15-year-old students from a random sample of schools in Denmark, response rate 87 per cent, n = 5,205. The data collection followed the…

  17. Increasing the Degrees of Freedom in Future Group Randomized Trials: The "df*" Method Revisited

    Science.gov (United States)

    Murray, David M.; Blitstein, Jonathan L.; Hannan, Peter J.; Shadish, William R.

    2012-01-01

    Background: This article revisits an article published in Evaluation Review in 2005 on sample size estimation and power analysis for group-randomized trials. With help from a careful reader, we learned of an important error in the spreadsheet used to perform the calculations and generate the results presented in that article. As we studied the…

  18. Revisiting Individual Creativity Assessment: Triangulation in Subjective and Objective Assessment Methods

    Science.gov (United States)

    Park, Namgyoo K.; Chun, Monica Youngshin; Lee, Jinju

    2016-01-01

    Compared to the significant development of creativity studies, individual creativity research has not reached a meaningful consensus regarding the most valid and reliable method for assessing individual creativity. This study revisited 2 of the most popular methods for assessing individual creativity: subjective and objective methods. This study…

  19. Revisiting First-Year College Students' Mattering: Social Support, Academic Stress, and the Mattering Experience

    Science.gov (United States)

    Rayle, Andrea Dixon; Chung, Kuo-Yi

    2008-01-01

    In this study, Nancy Schlossberg's (1989) theory of college students' mattering to others was revisited. Mattering is the experience of others depending on us, being interested in us, and being concerned with our fate. The relationships of gender, mattering to college friends and the college environment, and friend and family social support with…

  20. Focused electron beam induced processing and the effect of substrate thickness revisited

    DEFF Research Database (Denmark)

    van Dorp, W. F.; Beyer, A.; Mainka, M.;

    2013-01-01

    with Monte Carlo simulations for SE emission. The results suggest that SEs are dominant in the dissociation of W(CO)6 on thin membranes. The best agreement between simulations and experiment is obtained for SEs with energies between 3 and 6 eV.With this work we revisit earlier experiments, working...

  1. The Best and the Rest: Revisiting the Norm of Normality of Individual Performance

    Science.gov (United States)

    O'Boyle, Ernest, Jr.; Aguinis, Herman

    2012-01-01

    We revisit a long-held assumption in human resource management, organizational behavior, and industrial and organizational psychology that individual performance follows a Gaussian (normal) distribution. We conducted 5 studies involving 198 samples including 633,263 researchers, entertainers, politicians, and amateur and professional athletes.…

  2. Instant Video Revisiting for Reflection: Extending the Learning of Children and Teachers.

    Science.gov (United States)

    Hong, Seong B.; Broderick, Jane T.

    This article discusses how instant video revisiting (IVR) promotes reflective thinking for both teachers and children. IVR was used as a daily classroom experience with both the children and the teachers throughout one semester in two preschool classrooms with children 2.5 to 5 years old. The teachers used a digital video camera to generate data…

  3. What are museums for? - Revisiting “Museums in a Troubled World”

    DEFF Research Database (Denmark)

    Søndergaard, Morten Karnøe; Janes, Robert

    2012-01-01

    Focusing on the present situation in the Nordic museum scene, entailing economic pressures and restructuring, this article introduces the thoughts and ideas of Canadian museum expert and author, Robert R. Janes, to put things in perspective. After revisiting the 2009 book “Museums in a Troubled W...

  4. The solution of an open XXZ chain with arbitrary spin revisited

    CERN Document Server

    Murgan, Rajan

    2014-01-01

    The Bethe ansatz solution for an open XXZ spin chain with arbitrary spin with N sites and nondiagonal boundary terms is revisited. The anisotropy parameter has values \\eta = i \\pi r/q, where r and q are positive integers with q restricted to odd integers. Numerical results are presented to support the solution.

  5. Revisiting "Grutter" and "Gratz" in the Wake of "Fisher": Looking Back to Move Forward

    Science.gov (United States)

    Ledesma, Maria C.

    2013-01-01

    This article revisits the University of Michigan's 2003 affirmative action cases, "Grutter v. Bollinger" and "Gratz v. Bollinger." Through the aid of critical textual analysis and critical race theory, the author looks back at the predominant narratives that framed the challenge to, and defense of, race-conscious affirmative action policy in the…

  6. The Relationship between Undergraduate Attendance and Performance Revisited: Alignment of Student and Instructor Goals

    Science.gov (United States)

    Westerman, James W.; Perez-Batres, Luis A.; Coffey, Betty S.; Pouder, Richard W.

    2011-01-01

    We revisit the relationship between attendance and performance in the undergraduate university setting and apply agency theory in the instructor-student context. Building on agency theory propositions in the educational setting advanced by Smith, Zsidisin, and Adams (2005), we propose that the student and instructor must align goals to promote the…

  7. Framing the Future: Revisiting the Place of Educational Expectations in Status Attainment

    Science.gov (United States)

    Bozick, Robert; Alexander, Karl; Entwisle, Doris; Dauber, Susan; Kerr, Kerri

    2010-01-01

    This study revisits the Wisconsin model of status attainment from a life course developmental perspective. Fixed-effects regression analyses lend strong support to the Wisconsin framework's core proposition that academic performance and significant others' influence shape educational expectations. However, investigating the process of expectation…

  8. Revisiting the Gun Ownership and Violence Link; a multi- level analysis of victimisation survey data.

    NARCIS (Netherlands)

    van Kesteren, J.N.

    2014-01-01

    The link between gun ownership victimisation by violent crime remains one of the most contested issues in criminology. Some authors claim that high gun availability facilitates serious violence. Others claim that gun ownership prevents crime. This article revisits these issues using individual and a

  9. Revisiting Feminism and Australian Education: Who Speaks? What Questions? What Contexts? What Impact?

    Science.gov (United States)

    Yates, Lyn

    2008-01-01

    This article revisits the development of feminist research and policy in education in Australia in the mid-1970s to mid-1980s from the perspective of the present decade. The purpose is to give one insider's account of the specificities of that initial period, and to use that analysis to draw attention to changes evident in the context and agendas…

  10. Revisiting the Didactic Triangle in the Case of an Adaptive Learning System

    Directory of Open Access Journals (Sweden)

    Yassine Zaoui Seghroucheni

    2014-10-01

    Full Text Available In this paper we revisit the classical approach of the didactic triangle designed for the classical learning situation (face to face and adapt it to the situation of an adaptive learning system, we discuss also the different components involved in this didactic triangle and how they interact and influence the learning process in an adaptive learning system.

  11. The solution of an open XXZ chain with arbitrary spin revisited

    Science.gov (United States)

    Murgan, Rajan; Silverthorn, Chris

    2015-02-01

    The Bethe ansatz solutions for an open XXZ spin chain with arbitrary spin with N sites and nondiagonal boundary terms are revisited. The anisotropy parameter, for cases considered here, has values η = iπ \\frac{r}{q} , where r and q are positive integers with q restricted to odd integers. Numerical results are presented to support the solutions.

  12. The skeptical green consumer revisited: testing the relationship between green consumerism and skepticism toward advertising

    NARCIS (Netherlands)

    J. Matthes; A. Wonneberger

    2014-01-01

    This article revisits the widely believed notion of the skeptical green consumer, in other words, that green consumers tend to distrust green advertising. Study 1, a survey of U.S. consumers, found no positive relationship between green consumerism and general ad skepticism. However, green consumeri

  13. Service-Learning in Crisis Communication Education: Revisiting Coombs' Objectives for the Crisis Communication Course

    Science.gov (United States)

    Maresh-Fuehrer, Michelle M.

    2015-01-01

    The purpose of this study was to revisit Coombs' suggestions for teaching the crisis communication course using service-learning as a framework. The author sought to assess the effectiveness of using this method in terms of the benefits to both students and the partnering organization and students' perceptions of whether they met the learning…

  14. Host–guest complexes between cryptophane-C and chloromethanes revisited

    OpenAIRE

    Takacs, Z.; Soltesova, M; Kowalewski, J.; Lang, J.; Brotin, T; Dutasta, J-P

    2012-01-01

    Cryptophane-C is composed of two nonequivalent cyclotribenzylene caps, one of which contains methoxy group substituents on the phenyl rings. The two caps are connected by three OCH2CH2O linkers in an anti arrangement. Host–guest complexes of cryptophane-C with dichloromethane and chloroform in solution were investigated in detail by nuclear magnetic resonance techniques and density functional theory (DFT) calculations. Variable temperature proton and carbon-13 spectra show a variety of dynami...

  15. Revisiting noninteracting string partition functions in Rindler space

    Science.gov (United States)

    Mertens, Thomas G.; Verschelde, Henri; Zakharov, Valentin I.

    2016-05-01

    We revisit noninteracting string partition functions in Rindler space by summing over fields in the spectrum. In field theory, the total partition function splits in a natural way into a piece that does not contain surface terms and a piece consisting of solely the so-called edge states. For open strings, we illustrate that surface contributions to the higher-spin fields correspond to open strings piercing the Rindler origin, unifying the higher-spin surface contributions in string language. For closed strings, we demonstrate that the string partition function is not quite the same as the sum over the partition functions of the fields in the spectrum: an infinite overcounting is present for the latter. Next we study the partition functions obtained by excluding the surface terms. Using recent results of He et al. [J. High Energy Phys. 05 (2015) 106], this construction, first done by Emparan [arXiv:hep-th/9412003], can be put on much firmer ground. We generalize to type II and heterotic superstrings and demonstrate modular invariance. All of these exhibit an IR divergence that can be interpreted as a maximal acceleration close to the black hole horizon. Ultimately, since these partition functions are only part of the full story, divergences here should not be viewed as a failure of string theory: maximal acceleration is a feature of a faulty treatment of the higher-spin fields in the string spectrum. We comment on the relevance of this to Solodukhin's recent proposal [Phys. Rev. D 91, 084028 (2015)]. A possible link with the firewall paradox is apparent.

  16. The Coral Data Time Series Need To Be Revisited

    Science.gov (United States)

    Juillet-Leclerc, A.

    2004-12-01

    Coral skeleton is formed under organism control and its geochemical properties are strongly influenced by biological effects embedding environmental signal. Geochemists have been puzzled by the diversity of geochemical responses showed by colonies grown in a same area. By revisiting the Weber and Woodhead data series (1972), gathering data from enough colonies developed in similar conditions to provide a statistical isotopic value representative of one site, we demonstrate that for Porites and Acropora, the expected isotopic thermometer is revealed when the "vital effect" is removed. On the other hand, by using Acropora cultured in controlled condition, with changing temperature on a range comprised between 23 and 29°C, the comparison of oxygen and carbon isotopic values revealed the role played by kinetic fractionation. This apparent paradox of two co-existing fractionations is explained by the isotopic analyzes of wild and cultured corals operated at micrometer size scale taking into account of microstructures of the skeleton. Two different crystals appear to be the growth units of the skeleton, each crystal corresponding to a specific deposition mechanism. Thus, the measurement performed with a conventional method is a "bulk" measurement, which depends upon two isotopic fractionations. Some investigations underlined the discrepancy of the meaning of the inter-annual and seasonal isotopic records, which could be illustrated by different isotopic calibrations assessed from seasonal or annual data. It has been also explained by micrometer analyses of Porites aragonite. A smoothing at around 400microns of isotopic measurements as well as Sr/Ca indicates that at seasonal time scale the growth unit is the month. This is in agreement with extensive studies conducted by biologists describing the mechanism governing the formation of Porites skeleton: every month is deposited a framework which is progressively filled in. By combining biologists and geochemists knowledge

  17. Memory Revisited in Julian Barnes's The Sense of an Ending

    Directory of Open Access Journals (Sweden)

    Maricel Oró Piqueras

    2014-02-01

    Full Text Available An accumulation of years brings with it an accumulation of experiences. The revision of such experiences usually becomes more recurrent after retirement, a transition time from one period of life to another and, as such, a time in which we, human beings, have a tendency to take stock of our lives. This is actually one of the main issues present in Julian Barnes's last novel The Sense of an Ending (2011. When the main protagonist, a retired man quite comfortable and contented with his present life, receives an unexpected inheritance from the mother of a girlfriend from his university years, he is forced to track down a part of his life that he had left at the back of his mind a long time ago. As he explains his story, the protagonist and narrator of the novel raises a number of questions related to the quality and function of memory as one gets into old age. He experiments the unreliability of memory and questions to what extent memory is constructed through the remembered emotions that invaded him over that episode of his life rather than through the events as they actually took place. On the other hand, the act of revisiting and revising that specific episode, brings with it feelings of guilt and remorse as the protagonist realises that his past acts were not as noble as he remembered them to be. However, these acts are part of the past and they cannot be changed; thus, another question that the novel raises is how to account for those actions of which one does not feel proud and, more importantly, how to manage those bad memories as one gets older

  18. Revisiting perfect fluid dark matter: Observational constraints from our galaxy

    Directory of Open Access Journals (Sweden)

    Alexander A. Potapov

    2016-02-01

    Full Text Available We revisit certain features of an assumed spherically symmetric perfect fluid dark matter halo in the light of the observed data of our galaxy, the Milky Way (MW. The idea is to apply the Faber–Visser approach of combined observations of rotation curves and lensing to a first post-Newtonian approximation to “measure” the equation of state ω(r of the perfect fluid galactic halo. However, for the model considered here, no constraints from lensing are used as it will be sufficient to consider only the rotation curve observations. The lensing mass together with other masses will be just computed using recent data. Since the halo has attractive gravity, we shall impose the constraint that ω(r≥0 for r≤RMW, where RMW∼200 kpc is the adopted halo radius of our galaxy. The observed circular velocity ℓ (=2vc2/c02 from the flat rotation curve and a crucial adjustable parameter D appearing in the perfect fluid solution then yield different numerical ranges of ω(r. It is demonstrated that the computed observables such as the rotation curve mass, the lens mass, the post-Newtonian mass of our galaxy compare well with the recent mass data. We also calculate the Faber–Visser χ-factor, which is a measure of pressure content in the dark matter. Our analysis indicates that a range 0≤ω(r≤2.8×10−7 for the perfect fluid dark matter can reasonably describe the attractive galactic halo. This is a strong constraint indicating a dust-like CDM halo (ω∼0 supported also by CMB constraints.

  19. Revisiting perfect fluid dark matter: Observational constraints from our galaxy

    Science.gov (United States)

    Potapov, Alexander A.; Garipova, Guzel M.; Nandi, Kamal K.

    2016-02-01

    We revisit certain features of an assumed spherically symmetric perfect fluid dark matter halo in the light of the observed data of our galaxy, the Milky Way (MW). The idea is to apply the Faber-Visser approach of combined observations of rotation curves and lensing to a first post-Newtonian approximation to "measure" the equation of state ω (r) of the perfect fluid galactic halo. However, for the model considered here, no constraints from lensing are used as it will be sufficient to consider only the rotation curve observations. The lensing mass together with other masses will be just computed using recent data. Since the halo has attractive gravity, we shall impose the constraint that ω (r) ≥ 0 for r ≤RMW, where RMW ˜ 200 kpc is the adopted halo radius of our galaxy. The observed circular velocity ℓ (= 2 vc2 / c02) from the flat rotation curve and a crucial adjustable parameter D appearing in the perfect fluid solution then yield different numerical ranges of ω (r). It is demonstrated that the computed observables such as the rotation curve mass, the lens mass, the post-Newtonian mass of our galaxy compare well with the recent mass data. We also calculate the Faber-Visser χ-factor, which is a measure of pressure content in the dark matter. Our analysis indicates that a range 0 ≤ ω (r) ≤ 2.8 ×10-7 for the perfect fluid dark matter can reasonably describe the attractive galactic halo. This is a strong constraint indicating a dust-like CDM halo (ω ˜ 0) supported also by CMB constraints.

  20. The Angular Momentum of Baryons and Dark Matter Halos Revisited

    Science.gov (United States)

    Kimm, Taysun; Devriendt, Julien; Slyz, Adrianne; Pichon, Christophe; Kassin, Susan A.; Dubois, Yohan

    2011-01-01

    Recent theoretical studies have shown that galaxies at high redshift are fed by cold, dense gas filaments, suggesting angular momentum transport by gas differs from that by dark matter. Revisiting this issue using high-resolution cosmological hydrodynamics simulations with adaptive-mesh refinement (AMR), we find that at the time of accretion, gas and dark matter do carry a similar amount of specific angular momentum, but that it is systematically higher than that of the dark matter halo as a whole. At high redshift, freshly accreted gas rapidly streams into the central region of the halo, directly depositing this large amount of angular momentum within a sphere of radius r = 0.1R(sub vir). In contrast, dark matter particles pass through the central region unscathed, and a fraction of them ends up populating the outer regions of the halo (r/R(sub vir) > 0.1), redistributing angular momentum in the process. As a result, large-scale motions of the cosmic web have to be considered as the origin of gas angular momentum rather than its virialised dark matter halo host. This generic result holds for halos of all masses at all redshifts, as radiative cooling ensures that a significant fraction of baryons remain trapped at the centre of the halos. Despite this injection of angular momentum enriched gas, we predict an amount for stellar discs which is in fair agreement with observations at z=0. This arises because the total specific angular momentum of the baryons (gas and stars) remains close to that of dark matter halos. Indeed, our simulations indicate that any differential loss of angular momentum amplitude between the two components is minor even though dark matter halos continuously lose between half and two-thirds of their specific angular momentum modulus as they evolve. In light of our results, a substantial revision of the standard theory of disc formation seems to be required. We propose a new scenario where gas efficiently carries the angular momentum generated

  1. SU-E-I-43: Photoelectric Cross Section Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Haga, A; Nakagawa, K [The University of Tokyo Hospital, Tokyo (Japan); Kotoku, J [Teikyo University, Tokyo (Japan); Horikawa, Y [Juntendo University, Tokyo, Tokyo (Japan)

    2015-06-15

    Purpose: The importance of the precision in photoelectric cross-section value increases for recent developed technology such as dual energy computed tomography, in which some reconstruction algorithms require the energy dependence of the photo-absorption in each material composition of human being. In this study, we revisited the photoelectric cross-section calculation by self-consistent relativistic Hartree-Fock (HF) atomic model and compared with that widely distributed as “XCOM database” in National Institute of Standards and Technology, which was evaluated with localdensity approximation for electron-exchange (Fock)z potential. Methods: The photoelectric cross section can be calculated with the electron wave functions in initial atomic state (bound electron) and final continuum state (photoelectron). These electron states were constructed based on the selfconsistent HF calculation, where the repulsive Coulomb potential from the electron charge distribution (Hartree term) and the electron exchange potential with full electromagnetic interaction (Fock term) were included for the electron-electron interaction. The photoelectric cross sections were evaluated for He (Z=2), Be (Z=4), C (Z=6), O (Z=8), and Ne (Z=10) in energy range of 10keV to 1MeV. The Result was compared with XCOM database. Results: The difference of the photoelectric cross section between the present calculation and XCOM database was 8% at a maximum (in 10keV for Be). The agreement tends to be better as the atomic number increases. The contribution from each atomic shell has a considerable discrepancy with XCOM database except for K-shell. However, because the photoelectric cross section arising from K-shell is dominant, the net photoelectric cross section was almost insensitive to the different handling in Fock potential. Conclusion: The photoelectric cross-section program has been developed based on the fully self-consistent relativistic HF atomic model. Due to small effect on the Fock

  2. Revisiting Scaling Relations for Giant Radio Halos in Galaxy Clusters

    Science.gov (United States)

    Cassano, R.; Ettori, S.; Brunetti, G.; Giacintucci, S.; Pratt, G. W.; Venturi, T.; Kale, R.; Dolag, K.; Markevitch, Maxim L.

    2013-01-01

    Many galaxy clusters host megaparsec-scale radio halos, generated by ultrarelativistic electrons in the magnetized intracluster medium. Correlations between the synchrotron power of radio halos and the thermal properties of the hosting clusters were established in the last decade, including the connection between the presence of a halo and cluster mergers. The X-ray luminosity and redshift-limited Extended GMRT Radio Halo Survey provides a rich and unique dataset for statistical studies of the halos. We uniformly analyze the radio and X-ray data for the GMRT cluster sample, and use the new Planck Sunyaev-Zel'dovich (SZ) catalog to revisit the correlations between the power of radio halos and the thermal properties of galaxy clusters. We find that the radio power at 1.4 GHz scales with the cluster X-ray (0.1-2.4 keV) luminosity computed within R(sub 500) as P(sub 1.4) approx. L(2.1+/-0.2) - 500). Our bigger and more homogenous sample confirms that the X-ray luminous (L(sub 500) > 5 × 10(exp 44) erg/s)) clusters branch into two populations-radio halos lie on the correlation, while clusters without radio halos have their radio upper limits well below that correlation. This bimodality remains if we excise cool cores from the X-ray luminosities. We also find that P(sub 1.4) scales with the cluster integrated SZ signal within R(sub 500), measured by Planck, as P(sub 1.4) approx. Y(2.05+/-0.28) - 500), in line with previous findings. However, contrary to previous studies that were limited by incompleteness and small sample size, we find that "SZ-luminous" Y(sub 500) > 6×10(exp -5) Mpc(exp 2) clusters show a bimodal behavior for the presence of radio halos, similar to that in the radio-X-ray diagram. Bimodality of both correlations can be traced to clusters dynamics, with radio halos found exclusively in merging clusters. These results confirm the key role of mergers for the origin of giant radio halos, suggesting that they trigger the relativistic particle acceleration.

  3. Consensus Paper: Revisiting the Symptoms and Signs of Cerebellar Syndrome.

    Science.gov (United States)

    Bodranghien, Florian; Bastian, Amy; Casali, Carlo; Hallett, Mark; Louis, Elan D; Manto, Mario; Mariën, Peter; Nowak, Dennis A; Schmahmann, Jeremy D; Serrao, Mariano; Steiner, Katharina Marie; Strupp, Michael; Tilikete, Caroline; Timmann, Dagmar; van Dun, Kim

    2016-06-01

    The cerebellum is involved in sensorimotor operations, cognitive tasks and affective processes. Here, we revisit the concept of the cerebellar syndrome in the light of recent advances in our understanding of cerebellar operations. The key symptoms and signs of cerebellar dysfunction, often grouped under the generic term of ataxia, are discussed. Vertigo, dizziness, and imbalance are associated with lesions of the vestibulo-cerebellar, vestibulo-spinal, or cerebellar ocular motor systems. The cerebellum plays a major role in the online to long-term control of eye movements (control of calibration, reduction of eye instability, maintenance of ocular alignment). Ocular instability, nystagmus, saccadic intrusions, impaired smooth pursuit, impaired vestibulo-ocular reflex (VOR), and ocular misalignment are at the core of oculomotor cerebellar deficits. As a motor speech disorder, ataxic dysarthria is highly suggestive of cerebellar pathology. Regarding motor control of limbs, hypotonia, a- or dysdiadochokinesia, dysmetria, grasping deficits and various tremor phenomenologies are observed in cerebellar disorders to varying degrees. There is clear evidence that the cerebellum participates in force perception and proprioceptive sense during active movements. Gait is staggering with a wide base, and tandem gait is very often impaired in cerebellar disorders. In terms of cognitive and affective operations, impairments are found in executive functions, visual-spatial processing, linguistic function, and affective regulation (Schmahmann's syndrome). Nonmotor linguistic deficits including disruption of articulatory and graphomotor planning, language dynamics, verbal fluency, phonological, and semantic word retrieval, expressive and receptive syntax, and various aspects of reading and writing may be impaired after cerebellar damage. The cerebellum is organized into (a) a primary sensorimotor region in the anterior lobe and adjacent part of lobule VI, (b) a second sensorimotor

  4. High resolution wide swath revisit synthetic aper ture radar imaging mode and algorithm

    Institute of Scientific and Technical Information of China (English)

    Weihua Zuo; Yiming Pi; Rui Min

    2015-01-01

    Based on the squint mode, a high resolution wide swath revisit synthetic aperture radar (SAR) imaging mode is pro-posed. The transmitting antennas are configured as the single phase center multiple azimuth beams (SPC MAB). The formed two beams point to two different directions to obtain two images of the observed scenario. The receiving antennas are configured as displaced phase center multiple azimuth beams (DPC MAB) to decrease the required pulse repetition frequency (PRF). The de-creased PRF can ensure the high resolution wide swath imaging. Based on the analysis of the character of the return signal, a pro-cessing method named multiple beam multiple channel algorithm (MBMCA) is proposed to separate the aliased sub-beams’ echoes. The separated echoes are focused respectively to get the revisit imaging to the observed scenario. The simulation experiments ve-rify the validity and correctness of the proposed imaging mode and processing algorithm.

  5. Investigating Revisit Intentions for the Boutique Hotels of Penang-A UNESCO World Heritage Site

    OpenAIRE

    Yen-Nee Goh

    2015-01-01

    The growth in the number and variety of boutique hotels in tourist destinations has stimulated a wide range of research studies. Nevertheless, within Malaysia, the area remains under studied. In 2008, George Town, a popular heritage destination in Malaysia, was listed as a UNESCO world heritage site, and since then the number of boutique hotels and tourist arrivals have steadily grown. But, to date, there has been no investigation of the determinants of tourists’ revisit intention to boutique...

  6. Revisit boundary conditions for the self-adjoint angular flux formulation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yaqi [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gleicher, Frederick N. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    We revisit the boundary conditions for SAAF. We derived the equivalent parity variational form ready for coding up. The more rigorous approach of evaluating odd parity should be solving the odd parity equation coupled with the even parity. We proposed a symmetric reflecting boundary condition although neither positive definiteness nor even-odd decoupling is achieved. A simple numerical test verifies the validity of these boundary conditions.

  7. Revisiting the fundamental physical chemistry in heterogeneous photocatalysis : its thermodynamics and kinetics

    OpenAIRE

    Ohtani, Bunsho

    2014-01-01

    Although the history of photocatalysis research is not so long, many researchers have studied photocatalysis and a large number of papers on photocatalysis have been published. The objectives of this review paper are to revisit the fundamentals of photocatalysis, especially its thermodynamics and kinetics, which have not been reexamined in recent studies, to clarify the problems, if any, that prevent developments in the field of photocatalysis, and to present insights for future progress.

  8. Revisiting T2KK and T2KO physics potential and $\

    CERN Document Server

    Hagiwara, Kaoru; Okamura, Naotoshi; Takaesu, Yoshitaro

    2016-01-01

    We revisit the sensitivity study of the Tokai-to-Kamioka-and-Korea (T2KK) and Tokai-to-Kamioka-and-Oki (T2KO) proposals where a water Cerenkov detector with the 100 kton fiducial volume is placed in Korea ($L = 1000$ km) and Oki island ($L = 653$ km) in Japan, respectively, in addition to the Super-Kamiokande for determination of the neutrino mass hierarchy and leptonic CP phase ($\\delta_{CP}$). We systematically study the running ratio of the $\

  9. The environmental policy assumption revisited : Explaining trends in environmental concerns in France between 1971 and 2008

    OpenAIRE

    Bozonnet, Jean-Paul; Halpern, Charlotte

    2013-01-01

    Why do people declare themselves to be highly concerned by ecology in the long run but vary over time in their commitment to the environmental cause? This article seeks to address this question by revisiting the environmental policy hypothesis. More precisely, it argues that such an assumption has not been demonstrated empirically partly because of data unavailability and to the choice of indicators. This article contributes to the wider debate on the disconnect between environmental concern ...

  10. The Relationship between Destination Image, Food Image, and Revisiting Pattaya, Thailand

    OpenAIRE

    Sarunya Lertputtarak

    2012-01-01

    Destination image and food image are the essences of tourists’ destination selections. The purposes of thisresearch were to study tourists’ perception toward destination image and Thai food image as well as study therelationship between those two variables and the tourists’ intention to revisit. The research was conducted inPattaya, Thailand. A questionnaire was used to survey 476 foreign visitors by a convenience sampling method.The results demonstrated that the respondents perceived the Pat...

  11. Nice to kin and nasty to non-kin: revisiting Hamilton's early insights on eusociality

    OpenAIRE

    Boomsma, J.J.; d'Ettorre, P.

    2013-01-01

    When helping behaviour is costly, Hamiltonian logic implies that animals need to direct helpful acts towards kin, so that indirect fitness benefits justify the costs. We revisit inferences about nepotism and aggression in Hamilton's 1964 paper to argue that he overestimated the general significance of nepotism, but that other issues that he raised continue to suggest novel research agendas today. We now know that nepotism in eusocial insects is rare, because variation in genetic recognition c...

  12. Lipoabdominoplasty: Revisiting the Superior Pull-Down Abdominal Flap and New Approaches

    OpenAIRE

    Uebel, Carlos Oscar

    2009-01-01

    Abdominoplasty is a very common procedure, especially for patients with abdominal laxness, striaes, and muscle rectus diastases. With the advent of liposuction 28 years ago, we can improve body contouring by treating lipodystrophies in the epigastric, flank, trochanteric, and buttocks areas. The procedure combining abdominoplasty and liposuction is called lipoabdominoplasty. Many new techniques have been proposed since these procedures were introduced; we now revisit the superior pull-down ab...

  13. The Impact of the Internet on Marketing Strategy: Revisiting Early Predictions

    OpenAIRE

    Kaan Varnali

    2010-01-01

    This conceptual paper revisits and reviews early milestone literature of influential authors, who discuss the impact of the Internet on major forces that shape a company’s marketing strategy to assess whether their futurist predictions and conceptual claims turned out to be true or were later falsified by empirical research or market experience. In particular, the impact of the Internet on customers, design of products/services, pricing, marketing communications, intermediaries, publics, an...

  14. INCREASED 30-DAY EMERGENCY DEPARTMENT REVISITS AMONG HOMELESS PATIENTS WITH MENTAL HEALTH CONDITIONS

    OpenAIRE

    Lam, Chun Nok; Arora, Sanjay; Menchine, Michael

    2016-01-01

    Background: Patients with mental health conditions frequently use emergency medical services.  Many suffer from substance use and homelessness. If they utilize the ED as their primary source of care, potentially preventable frequent ED revisits and hospital readmissions can worsen an already over-crowded health care system. However, the magnitude to which homelessness affects health service utilization among patients with mental health conditions remains unclear in the medical community. This...

  15. A ICT "Literacy" Revisited: or What the Literate Citizen Really Needs to Know

    OpenAIRE

    Dan Fleming

    2004-01-01

    Use of the term ‘literacy’ to describe various sorts of competence in information and communication technologies (ICTs) has been widespread (e.g. digital literacy, media literacy) but this is usually little more than a vaguely defined metaphorical usage. The paper revisits the notion of literacy and uses British educational sociologist BasilBernstein’s analysis of codes and of classification and framing practices in order to suggest that there is a desirable form of ICT literacy that is more ...

  16. Grammatical relations and grammatical categories in Malay; The Indonesian prefix meN- revisited

    Directory of Open Access Journals (Sweden)

    Johnny Tjia

    2015-04-01

    Full Text Available The lexical roots of Malay are flexible with regard to their grammatical categories, which presents a problem in providing grammatical evidence for their category determination. This paper attempts to propose the use of affixes as one way to deal with the issue. Data from Indonesian and Ambon (Malay language are among others given for clarification. The grammatical evidence from Indonesian active meN-, together with other affixes, are revisited as they can contribute to our understanding of the matter.

  17. The Gate Theory of Pain Revisited: Modeling Different Pain Conditions with a Parsimonious Neurocomputational Model

    OpenAIRE

    Francisco Javier Ropero Peláez; Shirley Taniguchi

    2016-01-01

    The gate control theory of pain proposed by Melzack and Wall in 1965 is revisited through two mechanisms of neuronal regulation: NMDA synaptic plasticity and intrinsic plasticity. The Melzack and Wall circuit was slightly modified by using strictly excitatory nociceptive afferents (in the original arrangement, nociceptive afferents were considered excitatory when they project to central transmission neurons and inhibitory when projecting to substantia gelatinosa). The results of our neurocomp...

  18. Shake-Your-Head: Revisiting Walking-In-Place for Desktop Virtual Reality

    OpenAIRE

    Terziman L.; Marchal M.; Emily M.; Multon F.; Arnaldi B.; Lecuyer A.

    2010-01-01

    International audience The Walking-In-Place interaction technique was introduced to navigate infinitely in 3D virtual worlds by walking in place in the real world. The technique has been initially developed for users standing in immersive setups and was built upon sophisticated visual displays and tracking equipments. In this paper, we propose to revisit the whole pipeline of the Walking-In-Place technique to match a larger set of configurations and apply it notably to the context of deskt...

  19. The Festival of the Unconscious: The Unconscious Revisited at the Freud Museum, London

    OpenAIRE

    Pettican, Anneké; Mojsiewicz, Kristin; Lewis, Chara

    2015-01-01

    “Exciting things are happening at the Freud Museum London this summer. A century after Sigmund Freud’s revolutionary ideas reached a wider public, his final home, dedicated to preserving his legacy, has invited artists, designers, writers and performers to revisit Freud’s seminal paper The Unconscious (1915) Using a combination of psychological games, scientific and historical information and engaging displays and workshops, The Festival of the Unconscious will encourage visitors to think ...

  20. Revisiting the fundamental physical chemistry in heterogeneous photocatalysis: its thermodynamics and kinetics.

    Science.gov (United States)

    Ohtani, Bunsho

    2014-02-01

    Although the history of photocatalysis research is not so long, many researchers have studied photocatalysis and a large number of papers on photocatalysis have been published. The objectives of this review paper are to revisit the fundamentals of photocatalysis, especially its thermodynamics and kinetics, which have not been reexamined in recent studies, to clarify the problems, if any, that prevent developments in the field of photocatalysis, and to present insights for future progress.

  1. Is Sky the Limit? Revisiting ‘Exogenous Productivity of Judges’ Argument

    OpenAIRE

    Kamil Jonski; Daniel Mankowski

    2014-01-01

    This paper revisits ‘exogenous productivity of judges’ hypothesis, laid down in numerous Law & Economics studies based on ‘production function’ approach. It states that judges confronted with growing caseload pressure, adjust their productivity thereby increasing number of resolved cases. We attribute such results to assumptions regarding the shape of court’s ‘production function’, and present alternative – hockey-stick ‘production function’ model, explicitly taking into account the time ...

  2. National park visitor segments and their interest in rural tourism services and intention to revisit

    OpenAIRE

    SIEVÄNEN TUIJA; NEUVONEN MARJO; POUTA EIJA

    2015-01-01

    The study aims to understand national park visitors’ interests to use tourism services provided in the vicinity of Linnansaari, Seitseminen and Repovesi national parks in Southern Finland. Separate visitor groups were identified based on their use of tourism services and their intention to revisit the area. Data were generated from a questionnaire survey of 736 visitors to the national parks. The analyses revealed five dimensions of interest in tourism services from which five visitor groups ...

  3. Effects of tourism image and experiential value on revisit intention in tourism industry

    OpenAIRE

    Angela Ya-Ping Chang

    2014-01-01

    Food, clothing, housing, transport and amusement are the necessities of a modern life, in which amusement is even a key element for modern people. Tourism, as the dynamic activity of amusement, allows people to experience a colorful life and tourist spots to acquire economic benefits. For this reason, the effects of Tourism Image and Experiential Value on Revisit Intention in tourism industry are studied. Aiming at the visitors to Yushan National Park, a total of 500 copies of questionnaires ...

  4. Explaining tourists satisfaction and intention to revisit Nha Trang, Viet Nam

    OpenAIRE

    Tran, Thi Ai Cam

    2011-01-01

    The first purpose of the thesis is to find how visitors evaluate the quality of different facets or attributes of a destination image of Nha Trang, how satisfied they are with Nha Trang, loyalty intention to revisit and willingness to recommend Nha Trang to others. The second is to investigate what “image” is most important to explain global satisfaction with visiting Nha Trang. The third is to investigate how perceived quality, satisfaction and other motivational or dismotivational factors ...

  5. The Probability of Transition to Entrepreneurship Revisited: Wealth, Education and Age

    OpenAIRE

    Mondragon-Velez, Camilo

    2009-01-01

    This paper revisits the empirical relationship between the probability of transition to entrepreneurship and wealth. Given that wealth is correlated with both education and age, these observable characteristics cannot be treated as independent covariates in the estimation. Thus, I document the differences in the transition probability profile across age and education groups. The main result of this paper is that the estimated probability of transition to entrepreneurship is hump-shaped in wea...

  6. Are Girls the Fairer Sex in India? Revisiting Intra-Household Allocation of Education Expenditure

    OpenAIRE

    Azam, Mehtabul; Kingdon, Geeta

    2011-01-01

    This paper revisits the issue of the intra-household allocation of education expenditure with the recently available India Human Development Survey which refers to 2005 and covers both urban and rural areas. In addition to the traditional Engel method, the paper utilizes a Hurdle model to disentangle the decision to enroll (incur any educational expenditure) and the decision of how much to spend on education, conditional on enrolling. Finally the paper also uses household fixed effects to exa...

  7. Revisiting the Gun Ownership and Violence Link; a multi- level analysis of victimisation survey data.

    OpenAIRE

    van Kesteren, J.N.

    2014-01-01

    The link between gun ownership victimisation by violent crime remains one of the most contested issues in criminology. Some authors claim that high gun availability facilitates serious violence. Others claim that gun ownership prevents crime. This article revisits these issues using individual and aggregate data on gun ownership and victimisation from the ICVS. Analysis at country level shows that the level of hand gun ownership is positively related to serious violence but not for lesser ser...

  8. On the spike in hazard rates at unemployment benefit expiration: The signalling hypothesis revisited

    OpenAIRE

    Decreuse, Bruno; Kazbakova, Elvira

    2008-01-01

    We revisit the signalling hypothesis, whereby potential employers use the duration of unemployment as a signal as to the productivity of applicants. We suggest that the quality of sucha signal is very low when the unemployed receive unemployment benefits: individuals have good reasons to remain unemployed. Conversely, the signal becomes much more efficient once benefitshave elapsed: skilled workers should not stay unemployed in such cases. Therefore, the potential duration of unemployment ben...

  9. Trade Unions, immigration and immigrants in Europe revisited: Unions’ attitudes and actions under new conditions

    OpenAIRE

    Marino, S.; Penninx, R.; Roosblad, J.

    2015-01-01

    This paper revisits the comparative approach used by Penninx and Roosblad (Trade Unions, Immigration and Immigrants in Europe, 1960-1993. New York: Berghahn Books) to study trade unions’ attitudes and actions in relation to immigrant workers in seven Western European countries. It reassesses that approach and asks whether it remains valid, as economic, social, and political circumstances nowadays seem fundamentally different from those two to five decades ago. Each element of the original con...

  10. Revisiting the concept of inculturation in a modern Africa: A reflection on salient issues

    OpenAIRE

    George C. Nche; Lawrence N. Okwuosa; Theresa C. Nwaoga

    2016-01-01

    This article revisited the concept of ‘Inculturation’ in modern Africa. Through the use of a historical phenomenological method, the article averred that Inculturation of Christianity in modern Africa is a herculean task that demands absolute caution. Hence, the article discussed some salient issues such as the evolutionary nature of African culture; the unity of the Christendom; and the Christian ecological concern, which should be put into serious consideration in the entire process of incu...

  11. Effects of Chloroform Extract of Echinacea Purpurea on the Mouse’s Mono-Macrophage System%紫锥菊提取物对小鼠单核巨噬细胞系统功能的影响

    Institute of Scientific and Technical Information of China (English)

    吴江涛; 刘珂

    2001-01-01

    用昆明种小鼠进行碳粒廓清实验,观察烟台从加拿大引种的紫锥菊的氯仿提取物对小鼠单核巨噬细胞系统功能的影响.结果显示:该提取物在0.025,0.25,2.5,和22 μg/g四种剂量时,对正常昆明种小鼠的单核巨噬细胞系统功能都没有显著影响;在0.025 μg/g剂量时,对氢化可的松免疫抑制的昆明种小鼠的单核巨噬细胞系统功能有显著影响,可使该种小鼠下降了的碳粒廓清能力恢复到正常水平,这种作用与10 mg/g剂量的黄芪注射液的作用相当;但在0.25和 2.5 μg/g剂量时,对氢化可的松免疫抑制的昆明种小鼠的单核巨噬细胞系统功能没有显著影响.说明该引种的紫锥菊有可能成为我国的一种新的药用植物资源,其氯仿提取物有可能被开发成一种免疫恢复剂.%Carbon clearance test is carried out in Kunming mice to observe the effect of the chloroform extract of the Yantai-introduced-from-Canada-Echinacea purpurea on the function of mono-macrophage system. The results show that this extract has no significant effect on the function of the normal Kunming mice's mono-macrophage system at the dosages of 0.025, 0.25, 2.5 and 22 μg/g;at the dosage of 0.025 μg/g,it has a significant effect on the function of the hydrocortisone-immune-inhibited-Kunming mice's mono-macrophage system,it recovers the mice's reduced carbon clearance ability to the normal level and the effect is comparable to that of the Huang-Qi injection at the dosage of 10 mg/g; but at the dosages of 0.25 and 2.5 μg/g,it has no significant effect on the function of the hydrocortisone-immune-inhibited-Kunming mice's mono-macrophage system. The results imply that the introduced Echinacea purpurea may become a new medicinal plant resource of this country and the chloroform extract may be developed into an immune restorer.

  12. RNS derivation of N-point disk amplitudes from the revisited S-matrix approach

    Directory of Open Access Journals (Sweden)

    Luiz Antonio Barreiro

    2014-09-01

    Full Text Available Recently, in [7] we proposed a revisited S-matrix approach to efficiently find the bosonic terms of the open superstring low energy effective lagrangian (OSLEEL. This approach allows to compute the α′N terms of the OSLEEL using open superstring n-point amplitudes in which n is considerably lower than (N+2 (which is the order of the required amplitude to obtain those α′N terms by means of the conventional S-matrix approach. In this work we use our revisited S-matrix approach to examine the structure of the scattering amplitudes, arriving at a closed form for them. This is a RNS derivation of the formula first found by Mafra, Schlotterer and Stieberger [21], using the pure spinor formalism. We have succeeded doing this for the 5, 6 and 7-point amplitudes. In order to achieve these results we have done a careful analysis of the kinematical structure of the amplitudes, finding as a by-product a purely kinematical derivation of the BCJ relations (for N=4,5,6 and 7. Also, following the spirit of the revisited S-matrix approach, we have found the α′ expansions for these amplitudes up to α′6 order in some cases, by only using the well known open superstring 4-point amplitude, cyclic symmetry and tree level unitarity: we have not needed to compute any numerical series or any integral involving polylogarithms, at any moment.

  13. Taï chimpanzees anticipate revisiting high-valued fruit trees from further distances.

    Science.gov (United States)

    Ban, Simone D; Boesch, Christophe; Janmaat, Karline R L

    2014-11-01

    The use of spatio-temporal memory has been argued to increase food-finding efficiency in rainforest primates. However, the exact content of this memory is poorly known to date. This study investigated what specific information from previous feeding visits chimpanzees (Pan troglodytes verus), in Taï National Park, Côte d'Ivoire, take into account when they revisit the same feeding trees. By following five adult females for many consecutive days, we tested from what distance the females directed their travels towards previously visited feeding trees and how previous feeding experiences and fruit tree properties influenced this distance. To exclude the influence of sensory cues, the females' approach distance was measured from their last significant change in travel direction until the moment they entered the tree's maximum detection field. We found that chimpanzees travelled longer distances to trees at which they had previously made food grunts and had rejected fewer fruits compared to other trees. In addition, the results suggest that the chimpanzees were able to anticipate the amount of fruit that they would find in the trees. Overall, our findings are consistent with the hypothesis that chimpanzees act upon a retrieved memory of their last feeding experiences long before they revisit feeding trees, which would indicate a daily use of long-term prospective memory. Further, the results are consistent with the possibility that positive emotional experiences help to trigger prospective memory retrieval in forest areas that are further away and have fewer cues associated with revisited feeding trees.

  14. RNS derivation of N-point disk amplitudes from the revisited S-matrix approach

    Energy Technology Data Exchange (ETDEWEB)

    Barreiro, Luiz Antonio, E-mail: luiz.a.barreiro@gmail.com [Departamento de Física, UNESP, Rio Claro, São Paulo (Brazil); Instituto de Matemática e Computação, Universidade Federal de Itajubá, Itajubá, Minas Gerais (Brazil); Medina, Ricardo, E-mail: rmedina50@gmail.com [Instituto de Matemática e Computação, Universidade Federal de Itajubá, Itajubá, Minas Gerais (Brazil)

    2014-09-15

    Recently, in [7] we proposed a revisited S-matrix approach to efficiently find the bosonic terms of the open superstring low energy effective lagrangian (OSLEEL). This approach allows to compute the α{sup ′N} terms of the OSLEEL using open superstring n-point amplitudes in which n is considerably lower than (N+2) (which is the order of the required amplitude to obtain those α{sup ′N} terms by means of the conventional S-matrix approach). In this work we use our revisited S-matrix approach to examine the structure of the scattering amplitudes, arriving at a closed form for them. This is a RNS derivation of the formula first found by Mafra, Schlotterer and Stieberger [21], using the pure spinor formalism. We have succeeded doing this for the 5, 6 and 7-point amplitudes. In order to achieve these results we have done a careful analysis of the kinematical structure of the amplitudes, finding as a by-product a purely kinematical derivation of the BCJ relations (for N=4,5,6 and 7). Also, following the spirit of the revisited S-matrix approach, we have found the α{sup ′} expansions for these amplitudes up to α{sup ′6} order in some cases, by only using the well known open superstring 4-point amplitude, cyclic symmetry and tree level unitarity: we have not needed to compute any numerical series or any integral involving polylogarithms, at any moment.

  15. Tales of sociology and the nursing curriculum: revisiting the debates.

    Science.gov (United States)

    Aranda, Kay; Law, Kate

    2007-08-01

    . Sociology and the nursing curriculum; editorial. Nurse Education in Practice 4, 81-82; Mowforth, G., Harrison, J., Morris, M., 2005. An investigation into adult nursing students' experience of the relevance and application of behavioural sciences (biology, psychology and sociology) across two different curricula. Nurse Education Today 25, 41-48]. Much attention has been given to the role, utility and value of sociology mostly within pre-registration but also post-registration nursing curricula. Through an initial analysis of a series of letters appearing in The Nursing Times over a 12 week period in 2004, and using an analytical framework of four tales (realist, critical, deconstructive and reflexive) we revisit this relationship. Unlike previous debates our argument is that this relationship is more usefully viewed as emblematic of the legitimation crisis inherent in all modern projects. We argue that in order to move beyond the 'utility' discussion, an interrogation of the knowledge claims of both nursing and sociology is required.

  16. Increased 30-Day Emergency Department Revisits Among Homeless Patients with Mental Health Conditions

    Directory of Open Access Journals (Sweden)

    Chun Nok Lam

    2016-09-01

    Full Text Available Introduction: Patients with mental health conditions frequently use emergency medical services. Many suffer from substance use and homelessness. If they use the emergency department (ED as their primary source of care, potentially preventable frequent ED revisits and hospital readmissions can worsen an already crowded healthcare system. However, the magnitude to which homelessness affects health service utilization among patients with mental health conditions remains unclear in the medical community. This study assessed the impact of homelessness on 30-day ED revisits and hospital readmissions among patients presenting with mental health conditions in an urban, safety-net hospital. Methods: We conducted a secondary analysis of administrative data on all adult ED visits in 2012 in an urban safety-net hospital. Patient demographics, mental health status, homelessness, insurance coverage, level of acuity, and ED disposition per ED visit were analyzed using multilevel modeling to control for multiple visits nested within patients. We performed multivariate logistic regressions to evaluate if homelessness moderated the likelihood of mental health patients’ 30-day ED revisits and hospital readmissions. Results: Study included 139,414 adult ED visits from 92,307 unique patients (43.5±15.1 years, 51.3% male, 68.2% Hispanic/Latino. Nearly 8% of patients presented with mental health conditions, while 4.6% were homeless at any time during the study period. Among patients with mental health conditions, being homeless contributed to an additional 28.0% increase in likelihood (4.28 to 5.48 odds of 30-day ED revisits and 38.2% increase in likelihood (2.04 to 2.82 odds of hospital readmission, compared to non-homeless, non-mental health (NHNM patients as the base category. Adjusted predicted probabilities showed that homeless patients presenting with mental health conditions have a 31.1% chance of returning to the ED within 30-day post discharge and a 3

  17. The vacuum structure, special relativity theory and quantum mechanics revisited: a field theory-no-geometry approach

    International Nuclear Information System (INIS)

    The main fundamental principles characterizing the vacuum field structure are formulated and the modeling of the related vacuum medium and charged point particle dynamics by means of de- vised field theoretic tools are analyzed. The Maxwell electrodynamic theory is revisited and newly derived from the suggested vacuum field structure principles and the classical special relativity theory relationship between the energy and the corresponding point particle mass is revisited and newly obtained. The Lorentz force expression with respect to arbitrary non-inertial reference frames is revisited and discussed in detail, and some new interpretations of relations between the special relativity theory and quantum mechanics are presented. The famous quantum-mechanical Schroedinger type equations for a relativistic point particle in the external potential and magnetic fields within the quasiclassical approximation as the Planck constant (h/2π) → 0 and the light velocity c → ∞ are obtained. (author)

  18. The Vacuum Structure, Special Relativity Theory and Quantum Mechanics Revisited: A Field Theory-No-Geometry Approach

    CERN Document Server

    Bogolubov, Nikolaj N; Taneri, Ufuk

    2008-01-01

    The main fundamental principles characterizing the vacuum field structure are formulated, the modeling of the related vacuum medium and point charged particle dynamics by means of devised field theoretic tools is analyzed. The Maxwell electrodynamic theory is revisited and newly derived from the suggested vacuum field structure principles, the classical special relativity theory relationship between the energy and the corresponding point particle mass is revisited and newly obtained. The Lorentz force expression with respect to arbitrary non-inertial reference frames is revisited and discussed in detail, some new interpretations of relations between the special relativity theory and quantum mechanics are presented. The famous quantum-mechanical Schr\\"{o}dinger type equation for a relativistic point particle in the external potential field within the quasiclassical approximation as the Plank constant $\\hbar \\to 0$ is obtained.

  19. Un avenir ouvert pour une sociologie revisitée

    Directory of Open Access Journals (Sweden)

    Liliane Voyé

    2012-05-01

    Full Text Available Si l’on peut louer le souci de réflexivité qui anime la sociologie, il convient toutefois de dépasser ce stade du questionnement pour arriver à développer une sociologie moins inquiète d’elle-même. Les raisons de ce malaise sont diverses. Outre l’absence d’accord « sur un socle élémentaire de compétences exigibles » (François Dubet et Alain Caillé, la spécificité de son champ et de ses apports, comparée, par exemple, à l’histoire ou à la géographie, serait aussi une exigence importante, dont la rencontre la rendrait moins fragile. La question des méthodes qu’elle emploie mériterait également l’attention car celles-ci peuvent pécher par leurs faiblesses mais aussi parfois par leurs excès. L’objet même que se donne la sociologie appelle lui aussi une réflexion : la sociologie n’est pas du travail social frotté de science. Pourquoi dès lors privilégier l’étude des « problèmes sociaux » au sens courant du terme et ne pas s’intéresser aussi aux populations sans problème ou tout au moins se considérant comme telles ? Comme en médecine, les personnes saines aident à comprendre les maladies. À une époque où les changements se multiplient dans tous les domaines, la sociologie doit s’atteler à peaufiner sa conceptualisation et à repenser ses paradigmes, pour assumer pleinement son rôle social.An Open Future for a Revisited SociologyIf we can praise the concern for reflexivity that drives sociology, it should however go beyond the stage of questioning in order to develop a sociology that is less worried about itself. The reasons for this discomfort are various. Besides the lack of agreement « on the basis of elementary required skills » (François Dubet et Alain Caillé, the specificity of its field and its contributions, compared for example to history or geography, should also be an important requirement whose meeting would make it less fragile. The question of its methods

  20. Predicting Results of the Research Excellence Framework using Departmental h-Index -- Revisited

    CERN Document Server

    Mryglod, O; Holovatch, Yu; Berche, B

    2015-01-01

    We revisit our recent study [Predicting results of the Research Excellence Framework using departmental h-index, Scientometrics, 2014, 1-16; arXiv:1411.1996] in which we attempted to predict outcomes of the UK's Research Excellence Framework (REF~2014) using the so-called departmental $h$-index. Here we report that our predictions failed to anticipate with any accuracy either overall REF outcomes or movements of individual institutions in the rankings relative to their positions in the previous Research Assessment Exercise (RAE~2008).

  1. The Tension between the Decision and Control Perspectives of Accounting Revisited

    DEFF Research Database (Denmark)

    Christensen, John

    2009-01-01

    The accounting system is a carefully managed information system which is used for multiple purposes. Traditionally, the uses are categorized using the main headings of decision and control. Numerous conflicts are the consequence of the multi-purpose accounting system. The easy way out is apparently...... to use different accounting systems for different purposes. That is not the norm. The tensions are managed within a single accounting system and that leads to trade-offs in the accounting system. I will revisit these conflicts of uses of accounting systems using product costing, transfer pricing and fair...

  2. 2-Hy­droxy-3-meth­oxy­benzaldehyde (o-vanillin) revisited

    OpenAIRE

    David Shin; Peter Müller

    2012-01-01

    The structure of ortho-vanillin, C8H8O3, has been revisited with modern methods and at low temperature (100 K). The previous structure [Iwasaki et al. (1976). Acta Cryst. B32, 1264–1266] is confirmed, but geometric precision is improved by an order of magnitude. The C atom of the methoxy group lies close to the benzene ring plane, which is the most common geometry for –OMe groups lying ortho to –OH groups on an aromatic ring. The crystal structure displ...

  3. Silent cries, dancing tears: the metapsychology of art revisited/revised.

    Science.gov (United States)

    Aragno, Anna

    2011-04-01

    Against the backdrop of a broad survey of the literature on applied psychoanalysis, a number of concepts underpinning the metapsychology of art are revisited and revised: sublimation; interrelationships between primary and secondary processes; symbolization; "fantasy"; and "cathexis." Concepts embedded in dichotomous or drive/energic contexts are examined and reformulated in terms of a continuum of semiotic processes. Freudian dream structure is viewed as a biological/natural template for nonrepressive artistic forms of sublimation. The synthesis presented proposes a model of continuous rather than discontinuous processes, in a nonenergic, biosemiotic metatheoretical framework. PMID:21653915

  4. Psychosis as a disorder of reduced cathectic capacity: Freud's analysis of the Schreber case revisited.

    Science.gov (United States)

    McGlashan, Thomas H

    2009-05-01

    Approximately 100 years ago, a prominent German public figure name Daniel Schreber wrote memoirs of his experiences in asylums. His case was diagnosed Dementia Praecox at times and Paranoia at others by his treaters. Freud analyzed Schreber's memoirs from the perspective of his "libido" theory of developmentally organized mental "cathexes" or ideational/emotional investments in self and others. Revisiting Freud's analysis of the Schreber case suggests that it may represent the first theoretical articulation that the pathophysiologic core of psychosis is one of deficit, i.e., of diminished (organic) cathectic capacity for normal mental and affective investments in life.

  5. Sample selection versus two-part models revisited: the case of female smoking and drinking.

    Science.gov (United States)

    Madden, David

    2008-03-01

    There is a well-established debate between Heckman sample selection and two-part models in health econometrics, particularly when no obvious exclusion restrictions are available. Most of this debate has focussed on the application of these models to health care expenditure. This paper revisits the debate in the context of female smoking and drinking, and evaluates the two approaches on three grounds: theoretical, practical and statistical. The two-part model is generally favoured but it is stressed that this comparison should be carried out on a case-by-case basis.

  6. Impact of CP-violation on neutrino lepton number asymmetries revisited

    CERN Document Server

    Barenboim, Gabriela

    2016-01-01

    We revisit the effect of the (Dirac) CP-violating phase on neutrino lepton number asymmetries in both mass- and flavor-basis. We found that, even if there are sizable effects on muon- and tau-neutrino asymmetries, the effect on the asymmetry of electron-neutrinos is at most similar to the upper bound set by BBN for initial neutrino degeneracy parameters smaller than order unity. We also found that, for the asymmetries in mass-basis, the changes caused by CP-violation is of sub-\\% level which is unlikely to be accesible neither in the current nor in the forthcoming experiments.

  7. Marginalization: A Revisitation With Integration of Scholarship on Globalization, Intersectionality, Privilege, Microaggressions, and Implicit Biases.

    Science.gov (United States)

    Hall, Joanne M; Carlson, Kelly

    2016-01-01

    In 1994, the concept of marginalization was explored in an article in Advances in Nursing Science. This is a revisitation of the concept incorporating new scholarship. This update is founded on feminism, postcolonialism, critical race theory, and discourse deconstruction, all viewpoints that have been explicated in nursing. The purpose of this analysis is to look at new scholarship and concepts useful to applying marginalization in nursing knowledge development from the standpoint of Bourdieu's macro, meso, and micro levels. New scholarship includes globalization, intersectionality, privilege, microaggressions, and implicit bias. Implications for decreasing health disparities through this new scholarship are discussed. PMID:27490876

  8. Revisited: The South Dakota Board of Nursing theory-based regulatory decisioning model.

    Science.gov (United States)

    Damgaard, Gloria; Bunkers, Sandra Schmidt

    2012-07-01

    The authors of this column describe the South Dakota Board of Nursing's 11 year journey utilizing a humanbecoming theory-based regulatory decisioning model. The column revisits the model with an emphasis on the cocreation of a strategic plan guiding the work of the South Dakota Board of Nursing through 2014. The strategic plan was influenced by the latest refinements of the humanbecoming postulates and the humanbecoming community change concepts. A graphic picture of the decisioning model is presented along with future plans for the theory-based model.

  9. Vacuum Ultraviolet Photodissociation and Fourier Transform–Ion Cyclotron Resonance (FT-ICR) Mass Spectrometry: Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Jared B.; Robinson, Errol W.; Pasa-Tolic, Ljiljana

    2016-02-16

    We revisited the implementation of UVPD within the ICR cell of a FT-ICR mass spectrometer. UVPD performance characteristics were examined in the context of recent developments in the understanding of UVPD and in-cell tandem mass spectrometry. Efficient UVPD and photo-ECD of a model peptide and small protein within the ICR cell of a FT-ICR mass spectrometer are accomplished through appropriate modulation of laser pulse timing relative to ion magnetron motion and the potential applied to an ion optical element that photons impinge on. It is shown that UVPD yields efficient and extensive fragmentation resulting in excellent sequence coverage for model peptide and protein cations.

  10. Gray and Green Revisited: A Multidisciplinary Perspective of Gardens, Gardening, and the Aging Process

    OpenAIRE

    WRIGHT, SCOTT D.; Amy Maida Wadsworth

    2014-01-01

    Over fourteen years ago, the concept of “gray and green” was first introduced by Wright and Lund (2000) to represent a new awareness and a call for increased scholarship at the intersection of environmental issues and the aging process. This review paper revisits that concept with a fresh perspective on the specific role of gardens and gardening in the aging experience. As example, gardening is one of the most popular home-based leisure activities in the US and represents an important activit...

  11. Revisiting the Saffman-Taylor Experiment: Imbibition Patterns and Liquid-Entrainment Transitions

    Science.gov (United States)

    Levaché, Bertrand; Bartolo, Denis

    2014-07-01

    We revisit the Saffman-Taylor experiment focusing on the forced-imbibition regime where the displacing fluid wets the confining walls. We demonstrate a new class of invasion patterns that do not display the canonical fingering shapes. We evidence that these unanticipated patterns stem from the entrainment of thin liquid films from the moving meniscus. We then theoretically explain how the interplay between the fluid flow at the contact line and the interface deformations results in the destabilization of liquid interfaces. In addition, this minimal model conveys a unified framework which consistently accounts for all the liquid-entrainment scenarios that have been hitherto reported.

  12. The Allolobophora sturanyi species group revisited: Integrated taxonomy and new taxa (Clitellata: Megadrili

    Directory of Open Access Journals (Sweden)

    Szederjesi, T.

    2016-04-01

    Full Text Available The Allolobophora sturanyi Rosa, 1895 species group is revisited using DNA barcoding and morphology. Barcoding results corroborated the previous treatment of the Allolobophora sturanyi subspecies and furthermore proved that the morphologically similar Allolobophora gestroides Zicsi, 1970 species belong to this species group. Elaboration of new samples from the Apuseni Mts resulted in discovery of a new subspecies A. sturanyi biharica ssp. nov. from the summit of the Bihor range, and a new species A. zicsica from the Vladeasa range similar to A. gestroides described from Northern Hungary.

  13. ULYSSES comes full circle, before revisiting the Sun's poles

    Science.gov (United States)

    1998-04-01

    Ulysses discovered unusually strong magnetic waves in the polar regions. Another surprise concerns unexpected connections between the polar and equatorial regions. Rhythmic variations in the intensity of energetic particles and cosmic rays, recorded by Ulysses at high latitudes, originate in effects of the Sun's rotation much closer to the equator. Scientists are debating how their picture of the magnetic field in the heliosphere must change, to make sense of the Ulysses observations. Without this new knowledge of the solar wind's behaviour, and its widespread effects, shocks felt in the Earth's vicinity would remain incomprehensible. For two centuries, sketchy links between sunspots, auroras and magnetic storms have puzzled scientists. Results from Ulysses and other solar spacecraft, including ESA's SOHO and Cluster II, are expected to transform human understanding of solar-terrestrial events. The task is urgent because astronauts and technological systems are becoming ever more vulnerable to the stormy Sun. After the quiet Sun, a peak of activity When Ulysses conducted the first-ever investigation of the high-latitude heliosphere, the Sun was quiet, being near the minimum of solar activity. As scientists expected, the circumstances were ideal for revealing the underlying structure of the Sun's atmosphere and the solar wind, in their simplest form. With the first phase of the voyage safely and very productively completed, Ulysses faces a new challenge, as it continues along its unique path. Obeying a cycle of roughly eleven years, the Sun is once again becoming restless as sunspot activity builds towards the next peak around 2000. When Ulysses revisits the polar regions at that time it will encounter conditions vastly different from those of 1994-95. The international mission of exploration has already given a new and thought-provoking view of the heliosphere. Its findings at solar maximum are guaranteed to do the same, and to give new insights into the gusts and shocks

  14. Revisiting the melting temperature of NpO2 and the challenges associated with high temperature actinide compound measurements

    NARCIS (Netherlands)

    Böhler, R.; Welland, M.J.; De Bruycker, F.; Boboridis, K.; Janssen, A.; Eloirdi, R.; Konings, R.J.M.; Manara, D.

    2012-01-01

    This work revisits the melting behaviour of neptunium dioxide, an actinide compound which can be produced in the nuclear fuel during operation, and which has an important impact on the nuclear fuel and waste radioactivity especially on the very long term. The present experimental approach employs re

  15. Revisiting Risk in the 21st Century. Forum Focus. Volume 3, Issue 1, January-February 2005

    Science.gov (United States)

    Forum for Youth Investment, 2005

    2005-01-01

    Over the past year, dozens of articles have been published about excessive youth borrowing and spending (leading to high amounts of debt), new reactions to negative body image (such as plastic surgery), as well as more familiar risks like premarital sex and smoking. In Forum Focus: Revisiting Risk in the 21st Century, we explore these challenges…

  16. A Fresh Take on Democratic Education: Revisiting Rancière through the Notions of Emergence and Enaction

    Science.gov (United States)

    Bastrup-Birk, Henriette; Wildemeersch, Danny

    2013-01-01

    This paper aims at contributing to new ways of thinking about democratic education. We discuss how revisiting this concept may help raise fresh questions in relation to non-formal fora grappling with intricate sustainability issues that span international borders. Starting from Rancière's ideas on democracy, we first examine a conception of…

  17. Today's Teens, Their Problems, and Their Literature: Revisiting G. Robert Carlsen's "Books and the Teenage Reader" Thirty Years Later.

    Science.gov (United States)

    Carroll, Pamela Sissi

    1997-01-01

    Revisits G. Robert Carlsen's call for the use of young adult literature in the classroom by looking specifically at the emotional and reading needs of older adolescents, those in the upper grades. Discusses problems associated with adolescence in the late twentieth century and lists recommended young adult books that touch on those issues. (TB)

  18. Revisiting an Old Friend: The Practice and Promise of Cooperative Learning for the Twenty-First Century

    Science.gov (United States)

    Schul, James E.

    2011-01-01

    Cooperative learning has long been at the disposal of school teachers. However, it is often misunderstood by some teachers as just another form of collaborative group work. This article revisits cooperative learning, including a sampling of its popular variations, with practical approaches toward effectively integrating it into classroom…

  19. Genomic DNA Isolation by Phenol/Chloroform Extracting Method from Sheep Blood Clot%酚/氯仿抽提法提取绵羊凝血块中基因组DNA

    Institute of Scientific and Technical Information of China (English)

    曹果清; 莫清珊; 陈凤仙

    2009-01-01

    [Objective] The aim was to establish the method of extracting genomic DNA from sheep blood clot on the basis of the improvement of method for extracting genomic DNA from tissues. [Method]The genomic DNA with complete primary structure and high purity was obtained from the sheep blood clot after the steps of cutting the sheep blood clot with ophthalmic scissors, cell lysis with tissue DNA extracts and digested by proteinase K, extracting with phenol/chloroform and precipitating with ethanol were performed. [Result]The concentration of the extracted DNA was 159.90±0.70 ng/μl and the ratio of the A260/A280 was 1.80+0.01. The sheep microsatellite locus of BM203 was amplified by using the extracted DNA from the sheep blood clot as template of PCR, and the PCR result was perfect. [Conclusion]This method is simple and feasible, the quantity and quality of the extracted DNA can satisfy the demands for the subsequent researches. It is worth to extending and using for reference.%[目的]对组织DNA提取方法进行改进,建立一种从绵羊凝血块中提取基因组DNA的方法.[方法]将绵羊凝血块用眼科剪剪碎,用组织DNA抽提液裂解细胞,用蛋白酶K消化后,经过酚/氯仿抽提,无水乙醇沉淀获得基因组DNA.用NanoDrop ND-1000微型分光光度计检测DNA浓度和纯度.用0.8%琼脂糖凝胶电泳检验基因组DNA的完整性.以绵羊微卫星位点BM203为扩增位点,分别以F:5′-GGGTGTGACATTTTGTTCCC-3′,R:5′-CTGCTCGCCACTAGTCCTTC-3′为上下游引物,进行PCR扩增试验.PCR产物用1.5%琼脂糖凝胶电泳检测.[结果]提取的DNA浓度为(159.90±0.70) ng/μl,A260/A280比值为1.80±0.01,分子完整,结果理想.以从凝血块中提取的DNA为模板,对绵羊BM203微卫星位点进行了PCR扩增,扩增产物条带整齐、明亮、特导性强,扩增效果好.[结论]该方法简单、实用,提取的DNA可满足后续相关研究对DNA质量的要求,值得推广借鉴.

  20. Effects of the Chloroform Extracts of Kochia Scoparia (L.) Schrad on Several Enzyme Systems in Tetran ychus Viennensis%地肤子活性成分对山楂叶螨酯酶同工酶的影响

    Institute of Scientific and Technical Information of China (English)

    张慧荣; 刘素琪; 王海香; 郝晓娟; 莫海波; 曹挥

    2011-01-01

    实验研究了地肤子活性成分KFCE-2处理后,山楂叶螨体内的酯酶同工酶的影响.从聚丙烯酰胺凝胶电泳结果来看,在处理组中,没有检测到新的其它酶带.并且其酯酶酶带E1、E2比对照组的颜色要浅,而且图谱面积小;而E3在处理的12 h后完全消失.酯酶同工酶电泳图谱经UVP2凝胶成像系统扫描分析,从强度变化上可以看出,E2、E3带的活性从处理的4 h(LANE-a')开始活性就在逐渐减弱,尤其是E3带的活性在处理的12 h后(LANE-c'就完全被抑制.此外,在迁移率的变化上,处理组E1、E2带的迁移率有逐渐增大的趋势;E3带的迁移率在能观察到的两个时间内,有减小的趋势.这表明KFCE-2可能通过抑制山楂叶螨体内的酯酶同工酶的活性,并且通过特异性的结合,改变部分酯酶的活性结构,来降低其解毒代谢.这也表明了地肤子作为新型植物源农药具有良好的开发前景.%The changes of the activities of the esterase isoenzyme in Tetranychus Viennensis treated with chloroform extract of Kochia Scoparia (KFCE-2) were tested. The results of the polyacrylamide gel electrophoresis (PAGE) indicated that new band was not found in mites treated with KFCE-2, and the colors of the esterase bands Ei and E2 were lighter than that of the control group and the area of the maps were smaller. The band of E3 disappeared completely when treated after 12 h. When the electropherograms of PAGE were analyzed used UVP2 gel imaging system, we found from the change of intensity that the activities of the E2 and E3 bands tended to be weak after treated 4 h ( LANE-a'), especially the activity of the band E3 which was entirely suppressed after 12 h (LANE-C). Besides, the migration rate of the E1 and E2 bands tended to be enlarged and that of the E3 band was gradually decreased in the treated groups. The result showed that KFCE-2 could reduce the antidote metabolism of Tetranychus Viennensis by restraining the activities

  1. Kinetic theory of turbulence for parallel propagation revisited: Low-to-intermediate frequency regime

    International Nuclear Information System (INIS)

    A previous paper [P. H. Yoon, “Kinetic theory of turbulence for parallel propagation revisited: Formal results,” Phys. Plasmas 22, 082309 (2015)] revisited the second-order nonlinear kinetic theory for turbulence propagating in directions parallel/anti-parallel to the ambient magnetic field, in which the original work according to Yoon and Fang [Phys. Plasmas 15, 122312 (2008)] was refined, following the paper by Gaelzer et al. [Phys. Plasmas 22, 032310 (2015)]. The main finding involved the dimensional correction pertaining to discrete-particle effects in Yoon and Fang's theory. However, the final result was presented in terms of formal linear and nonlinear susceptibility response functions. In the present paper, the formal equations are explicitly written down for the case of low-to-intermediate frequency regime by making use of approximate forms for the response functions. The resulting equations are sufficiently concrete so that they can readily be solved by numerical means or analyzed by theoretical means. The derived set of equations describe nonlinear interactions of quasi-parallel modes whose frequency range covers the Alfvén wave range to ion-cyclotron mode, but is sufficiently lower than the electron cyclotron mode. The application of the present formalism may range from the nonlinear evolution of whistler anisotropy instability in the high-beta regime, and the nonlinear interaction of electrons with whistler-range turbulence

  2. Kinetic theory of turbulence for parallel propagation revisited: Low-to-intermediate frequency regime

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Peter H., E-mail: yoonp@umd.edu [University of Maryland, College Park, Maryland 20742 (United States); School of Space Research, Kyung Hee University, Yongin, Gyeonggi 446-701 (Korea, Republic of)

    2015-09-15

    A previous paper [P. H. Yoon, “Kinetic theory of turbulence for parallel propagation revisited: Formal results,” Phys. Plasmas 22, 082309 (2015)] revisited the second-order nonlinear kinetic theory for turbulence propagating in directions parallel/anti-parallel to the ambient magnetic field, in which the original work according to Yoon and Fang [Phys. Plasmas 15, 122312 (2008)] was refined, following the paper by Gaelzer et al. [Phys. Plasmas 22, 032310 (2015)]. The main finding involved the dimensional correction pertaining to discrete-particle effects in Yoon and Fang's theory. However, the final result was presented in terms of formal linear and nonlinear susceptibility response functions. In the present paper, the formal equations are explicitly written down for the case of low-to-intermediate frequency regime by making use of approximate forms for the response functions. The resulting equations are sufficiently concrete so that they can readily be solved by numerical means or analyzed by theoretical means. The derived set of equations describe nonlinear interactions of quasi-parallel modes whose frequency range covers the Alfvén wave range to ion-cyclotron mode, but is sufficiently lower than the electron cyclotron mode. The application of the present formalism may range from the nonlinear evolution of whistler anisotropy instability in the high-beta regime, and the nonlinear interaction of electrons with whistler-range turbulence.

  3. Economic Growth and Income Distribution in Chile: Macroeconomic Trade-Offs Revisited Economic Growth and Income Distribution in Chile: Macroeconomic Trade-Offs Revisited

    Directory of Open Access Journals (Sweden)

    Andrés Solimano

    1992-03-01

    Full Text Available Economic Growth and Income Distribution in Chile: Macroeconomic Trade-Offs Revisited Long run sustainable development requires both sustained growth and an equitable distribution of the fruits of growth and modernization. This paper analyzes the issue of maintaining the dynamic growth momentum of the Chilean economy while at the same time reducing poverty and improving income distribution patterns. The paper identifies the major constraints on growth for the chilean economy and develops a macro model to explore and quantify potential trade offs between growth, poverty reduction and distribution.The model is calibrated with parameters for the Chilean economy and used to examine the effects of various macro policies with distributive content. For example the model shows that an unbalanced increase in government spending (in social rectors of 3 percent of potential GDP, will slow down the rate of growth of GDP by 1 percent, the real exchange rate appreciates (5,4 percent and real wages rise (4.4 percent in a capacity constrained growth regime. The cut in government savings is the driving force behind the deceleration in growth, given a certain current account deficit. The adverse side effect on growth of the social program can be avoided with an increase in taxation or a reduction in other public spending items in order to prevent a decline in public savings.

  4. No Information Is Lost: a Revisit of Hawking Radiation as Tunneling

    CERN Document Server

    Zhang, Baocheng; Zhan, Ming-sheng; You, Li

    2009-01-01

    We revisit in detail the paradox of black hole information loss due to Hawking radiation as tunneling. We compute the amount of information encoded in correlations among Hawking radiations for a variety of black holes, including the Schwarzchild black hole, the Reissner-Nordstr\\"{o}m black hole, the Kerr black hole, and the Kerr-Newman black hole. The special cases of tunneling through a quantum horizon and geometrically non-commutative black holes are also considered. Within a phenomenological treatment based on the accepted emission probability spectrum from a black hole, we find that information is leaked out hidden in the correlations of Hawking radiation. The recovery of this previously unaccounted for information helps to conserve the total entropy of a system composed of a black hole plus its radiations. We thus conclude, irrespective of the microscopic picture for black hole collapsing, the associated radiation process: Hawking radiation as tunneling, must be a unitary process.

  5. Is Sky the Limit? Revisiting ‘Exogenous Productivity of Judges’ Argument

    Directory of Open Access Journals (Sweden)

    Kamil Jonski

    2014-12-01

    Full Text Available This paper revisits ‘exogenous productivity of judges’ hypothesis, laid down in numerous Law & Economics studies based on ‘production function’ approach. It states that judges confronted with growing caseload pressure, adjust their productivity thereby increasing number of resolved cases. We attribute such results to assumptions regarding the shape of court’s ‘production function’, and present alternative – hockey-stick ‘production function’ model, explicitly taking into account the time constraint faced by judges. Hence, we offer an attempt to reconcile ‘production function’ with more traditional approaches to the court performance – such as weighted caseload methods. We argue that such empirical strategy is particularly valuable in case of continental legal systems – characterized by higher procedural formalism. We also propose extended methodology of model evaluation, taking into account their ability to reproduce empirical regularities observed in ‘real world’ court systems.

  6. Tradução comentada do conto "Babylon revisited" de F. Scott Fitzgerald

    OpenAIRE

    Ferreira, Ana Teresa Ribeiro

    2015-01-01

    Este Trabalho de Projeto tem como objeto a tradução para Língua Portuguesa do conto Babylon Revisited do autor norte-americano F. Scott Fitzgerald, publicado pela primeira vez em 1931 na revista semanal Saturday Evenning Post. Na primeira parte do trabalho, procedeu-se a uma apresentação da vida e obra do autor, análise do conto e do contexto histórico e sócio-económico em que ambos se inserem. Na segunda parte faz-se uma exposição das teorias de tradução que mais diretamente influenciaram o ...

  7. Metapsychology or metapsychologies? Some comments on Paul Denis's paper 'The drive revisited: mastery and satisfaction'.

    Science.gov (United States)

    Sapisochin, Gabriel

    2016-06-01

    In this commentary on Paul Denis's paper 'The drive revisited: mastery and satisfaction', the author defends the idea of a plurality of metapsychologies that must be contrasted with and distinguished from each other while avoiding incompatible translations between models. In this connection he presents various theoretical approaches to aggression and the death drive, and demonstrates the differences between the drive model and the model underlying the theory of internalized object relations. The author holds that the concept of the internal object differs from Freud's notion of the representation (Vorstellung). He also considers that the imago as defined by Paul Denis in fact corresponds to the concept of the internal object. Lastly, he addresses the complex issue of listening to archaic forms of psychic functioning and their non-discursive presentation within the analytic process, which affects the transference-countertransference link. PMID:27437625

  8. Sn1987a Revisited after 20 Years: May the Supernova Bang More Than Once?

    CERN Document Server

    Galeotti, P

    2007-01-01

    The observations of supernova 1987A in underground detectors are revisited. It is shown that, while the LSD detector in the Mont Blanc Laboratory observed only one burst at 2h 52min 36.8sec U.T., the Kamiokande data show a possible second burst, in addition to the well known one at 7h 35min 33.7sec U.T. This second burst consists of a cluster of seven pulses, well above the energy threshold of the detector, observed during 6.2 seconds starting at 7h 54min 22.2sec U.T. Do these observations imply a long duration of the collapse?

  9. SN1987A: Revisiting the Data and the Correlation between Neutrino and Gravitational Detectors

    CERN Document Server

    Galeotti, P; Pizzella, G

    2008-01-01

    We re-examine the data taken by the neutrino detectors during the supernova SN1987A. It is found that the Kamiokande data, in addition to the well known burst at 7:35 hours UT, show another one at 7:54 hours, with seven pulses in 6.2 seconds. This second burst supports the idea that the duration of the collapse was much longer than a few seconds, as already suggested by the LSD detection at 2:56 hours the same day, i.e. four and a half hours earlier. The correlations between the gravitational wave detectors (Rome and Maryland) and the neutrino detectors are also revisited. It is shown that the g.w. detectors exhibit significant correlations with both the LSD and the Kamiokande detectors over periods of one-two hours that are centered, in both cases, at the LSD time.

  10. Revisiting the Age of Enlightenment from a Collective Decision Making Systems Perspective

    CERN Document Server

    Rodriguez, Marko A

    2009-01-01

    The ideals of the eighteenth century's Age of Enlightenment are the foundation of modern democracies. The era was characterized by thinkers who promoted progressive social reforms that opposed the long-established aristocracies and monarchies of the time. Prominent examples of such reforms include the establishment of inalienable human rights, self-governing republics, and market capitalism. Twenty-first century democratic nations can benefit from revisiting the systems developed during the Enlightenment and reframing them within the techno-social context of the Information Age. This article explores the application of social algorithms that make use of Thomas Paine's (English: 1737--1809) representatives, Adam Smith's (Scottish: 1723--1790) self-interested actors, and Marquis de Condorcet's (French: 1743--1794) optimal decision making groups. It is posited that technology-enabled social algorithms can better realize the ideals articulated during the Enlightenment.

  11. Ethylene Control of Fruit Ripening: Revisiting the Complex Network of Transcriptional Regulation.

    Science.gov (United States)

    Liu, Mingchun; Pirrello, Julien; Chervin, Christian; Roustan, Jean-Paul; Bouzayen, Mondher

    2015-12-01

    The plant hormone ethylene plays a key role in climacteric fruit ripening. Studies on components of ethylene signaling have revealed a linear transduction pathway leading to the activation of ethylene response factors. However, the means by which ethylene selects the ripening-related genes and interacts with other signaling pathways to regulate the ripening process are still to be elucidated. Using tomato (Solanum lycopersicum) as a reference species, the present review aims to revisit the mechanisms by which ethylene regulates fruit ripening by taking advantage of new tools available to perform in silico studies at the genome-wide scale, leading to a global view on the expression pattern of ethylene biosynthesis and response genes throughout ripening. Overall, it provides new insights on the transcriptional network by which this hormone coordinates the ripening process and emphasizes the interplay between ethylene and ripening-associated developmental factors and the link between epigenetic regulation and ethylene during fruit ripening.

  12. Revisiting Hartle's model using perturbed matching theory to second order: amending the change in mass

    CERN Document Server

    Reina, Borja

    2014-01-01

    Hartle's model describes the equilibrium configuration of a rotating isolated compact body in perturbation theory up to second order in General Relativity. The interior of the body is a perfect fluid with a barotropic equation of state, no convective motions and rigid rotation. That interior is matched across its surface to an asymptotically flat vacuum exterior. Perturbations are taken to second order around a static and spherically symmetric background configuration. Apart from the explicit assumptions, the perturbed configuration is constructed upon some implicit premises, in particular the continuity of the functions describing the perturbation in terms of some background radial coordinate. In this work we revisit the model within a modern general and consistent theory of perturbative matchings to second order, which is independent of the coordinates and gauges used to describe the two regions to be joined. We explore the matching conditions up to second order in full. The main particular result we presen...

  13. Revisiting the spectrum of a scalar field in an anisotropic universe

    CERN Document Server

    Kim, Hyeong-Chan

    2012-01-01

    We revisit the issue on signatures of pre-inflationary background anisotropy by considering the quantization of a massless and minimally coupled scalar field in an axially symmetric Kasner background, mimicking cosmological perturbations. We show that the power spectrum of the scalar field fluctuation has a negligible difference from the standard inflation in the non-planar directions, but it has a sharp peak around the symmetry plane. For the non-planar high-momentum modes, we use the WKB approximation for the first period and the asymptotic approximation based on the de Sitter solution for the next period. At the boundary, two mode functions have the same accuracy with error of $O({H_{i}}/k)$. We calculate the approximation up to the order of $({H_{i}}/k)^6$ and show that the power spectrum of the scalar field fails to get corrections until we execute the approximation up to $6^{\\rm th}$ order.

  14. Revisiting scalar quark hidden sector in light of 750-GeV diphoton resonance

    Science.gov (United States)

    Chiang, Cheng-Wei; Ibe, Masahiro; Yanagida, Tsutomu T.

    2016-05-01

    We revisit the model of a CP -even singlet scalar resonance proposed in arXiv:1507.02483 URL"/> , where the resonance appears as the lightest composite state made of scalar quarks participating in hidden strong dynamics. We show that the model can consistently explain the excess of diphoton events with an invariant mass around 750 GeV reported by both the ATLAS and CMS experiments. We also discuss the nature of the charged composite states in the TeV range which accompany to the neutral scalar. Due to inseparability of the dynamical scale and the mass of the resonance, the model also predicts signatures associated with the hidden dynamics such as leptons, jets along with multiple photons at future collider experiments. We also associate the TeV-scale dynamics behind the resonance with an explanation of dark matter.

  15. A fussy revisitation of antiprotons as a tool for Dark Matter searches

    CERN Document Server

    Boudaud, Mathieu

    2015-01-01

    Antiprotons are regarded as a powerful probe for Dark Matter (DM) indirect detection and indeed current data from \\PAMELA\\ have been shown to lead to stringent constraints. However, in order to exploit their constraining/discovery power properly, great attention must be put into effects (linked to their propagation in the Galaxy) which may be perceived as subleading but actually prove to be quite relevant. We revisit the computation of the astrophysical background and of the DM antiproton fluxes fully including the effects of: diffusive reacceleration, energy losses including tertiary component and solar modulation (in a force field approximation). Using the updated proton and helium fluxes just released by the \\AMS\\ experiment we reevaluate the secondary astrophysical antiproton to proton ratio and its uncertainties, and compare it with the ratio preliminarly reported by \\AMS. We find no unambiguous evidence for a significant excess with respect to expectations. Yet, some preference for a flatter energy depe...

  16. Nice to kin and nasty to non-kin: revisiting Hamilton's early insights on eusociality.

    Science.gov (United States)

    Boomsma, Jacobus J; d'Ettorre, Patrizia

    2013-01-01

    When helping behaviour is costly, Hamiltonian logic implies that animals need to direct helpful acts towards kin, so that indirect fitness benefits justify the costs. We revisit inferences about nepotism and aggression in Hamilton's 1964 paper to argue that he overestimated the general significance of nepotism, but that other issues that he raised continue to suggest novel research agendas today. We now know that nepotism in eusocial insects is rare, because variation in genetic recognition cues is insufficient. A lower proportion of individuals breeding and larger clutch sizes selecting for a more uniform colony odour may explain this. Irreversible worker sterility can induce both the fiercest possible aggression and the highest likelihood of helping random distant kin, but these Hamiltonian contentions still await large-scale testing in social animals. PMID:24132094

  17. Thermal ignition revisited with molecular dynamics: role of fluctuations in activated collisions

    CERN Document Server

    Sirmas, Nick

    2016-01-01

    The problem of thermal ignition in a homogeneous gas is revisited from a molecular dynamics perspective. The simple model assumes reactive particles of type A and B in a fixed domain that react to form type C products if an activation threshold for impact is surpassed. Such a reaction liberates kinetic energy to the product particles, representative of the heat release. The results are compared with those obtained from the continuum description with the reaction rate evaluated from kinetic theory assuming local thermodynamic equilibrium and Maxwell-Boltzmann statistics, in order to assess the role played by molecular fluctuations. Results show that at low activation energies, the ignition time obtained from the molecular dynamics is independent of domain size, with values exceeding what is expected from the continuum model for all values of heat release. The ignition time was found dependent on domain size for larger activation energies. Small domains of $N=100$ particles yielded longer ignition delays than p...

  18. Revisited the mathematical derivation wall thickness measurement of pipe for radiography

    Energy Technology Data Exchange (ETDEWEB)

    Hamzah, A.R.; Amir, S.M.M. [Non Destructive Testing(NDT) Group, Industrial Technology Div., Malaysian Nuclear Agency, Selangor (Malaysia)

    2007-07-01

    Wall thickness measurement of pipe is very important of the structural integrity of the industrial plant. However, the radiography method has an advantage because the ability of penetrating the insulated pipe. This will have economic benefit for industry. Moreover, the era of digital radiography has more advantages because the speed of radiographic work, less exposure time and no chemical used for film development. Either the conventional radiography or digital radiology, the wall thickness measurement is using the tangential radiography technique (TRT). In case, of a large diameter, pipe (more than inches) the determination maximum penetration wall thickness must be taken into the consideration. This paper is revisited the mathematical derivation of the determination of wall thickness measurement based on tangential radiography technique (TRT). The mathematical approach used in this derivation is the Pythagoras theorem and geometrical principles. In order to derive the maximum penetration wall thickness a similar approach is used. (authors)

  19. Biochemical reactions in crowded environments: Revisiting the effects of volume exclusion with simulations

    Directory of Open Access Journals (Sweden)

    David eGomez

    2015-06-01

    Full Text Available Molecular crowding is ubiquitous within cells and affects many biological processes including protein-protein binding, enzyme activities and gene regulation. Here we revisit some generic effects of crowding using a combination of lattice simulations and reaction-diffusion simulations with the program ReaDDy. Specifically, we implement three reactions, simple binding, a diffusion-limited reaction and a reaction with Michaelis-Menten kinetics. Histograms of binding and unbinding times provide a detailed picture how crowding affects these reactions and how the separate effects of crowding on binding equilibrium and on diffusion act together. In addition, we discuss how crowding affects processes related to gene expression such as RNA polymerase-promoter binding and translation elongation.

  20. What drives health care expenditure?--Baumol's model of 'unbalanced growth' revisited.

    Science.gov (United States)

    Hartwig, Jochen

    2008-05-01

    The share of health care expenditure in GDP rises rapidly in virtually all OECD countries, causing increasing concern among politicians and the general public. Yet, economists have to date failed to reach an agreement on what the main determinants of this development are. This paper revisits Baumol's [Baumol, W.J., 1967. Macroeconomics of unbalanced growth: the anatomy of urban crisis. American Economic Review 57 (3), 415-426] model of 'unbalanced growth', showing that the latter offers a ready explanation for the observed inexorable rise in health care expenditure. The main implication of Baumol's model in this context is that health care expenditure is driven by wage increases in excess of productivity growth. This hypothesis is tested empirically using data from a panel of 19 OECD countries. Our tests yield robust evidence in favor of Baumol's theory. PMID:18164773

  1. Multiconfiguration Dirac-Hartree-Fock calculations for be-like intercombination lines revisited

    International Nuclear Information System (INIS)

    Multiconfiguration Dirac-Hartree-Fock (MCDHF) calculations for the 2s21S0-2s2p 3P1 intercombination transitions are revisited for the elements N+3-Mg+8, and for Fe+22 where previous results produced transition rates that were too small when compared with similar multiconfiguration Hartree-Fock-Breit-Pauli values. By optimizing on both the first and second eigenvalue for J=1, the wave functions for the 2s2p 3P1 state produced transition rates that are within the uncertainty limits of recent Breit-Pauli calculations. The case of C+2 is also discussed where previous theory and experiment are in excellent agreement. (orig.)

  2. Multiconfiguration Dirac-Hartree-Fock calculations for be-like intercombination lines revisited

    Energy Technology Data Exchange (ETDEWEB)

    Froese Fischer, C. [Vanderbilt Univ., Nashville, TN (United States). Dept. of Computer Science

    2000-12-01

    Multiconfiguration Dirac-Hartree-Fock (MCDHF) calculations for the 2s{sup 2} {sup 1}S{sub 0}-2s2p {sup 3}P{sub 1} intercombination transitions are revisited for the elements N{sup +3}-Mg{sup +8}, and for Fe{sup +22} where previous results produced transition rates that were too small when compared with similar multiconfiguration Hartree-Fock-Breit-Pauli values. By optimizing on both the first and second eigenvalue for J=1, the wave functions for the 2s2p {sup 3}P{sub 1} state produced transition rates that are within the uncertainty limits of recent Breit-Pauli calculations. The case of C{sup +2} is also discussed where previous theory and experiment are in excellent agreement. (orig.)

  3. Revisiting Caresharing in the Context of Changes in a Florida Retirement Community

    Directory of Open Access Journals (Sweden)

    Eleanor Krassen Covan, Ph. D.

    2006-06-01

    Full Text Available In this paper I revisit the basic social process ofcaresharing whereby people engage in personal and communal strategies to maximize their pleasure and minimize their losses. I originally discovered caresharing in the context of Hollywood Falls, a Florida retirement community that provided no formal supportive services for its aging residents (Covan, 1998. There, hiding frailty was the most obvious caresharing strategy. In this community which has since become more diverse in terms of ethnicity and age, hiding frailty is no longer practical among the oldest residents. It has been surpassed by bolstering strength, a process which involves exposing need, expanding the caresharing network, stifling crises, and staking competence claims. In consequence of bolstering strength, the oldest residents are able to diminish the costs of help while augmenting opportunities for personal autonomy, thereby extending their period of residence within their ‘independent’ living community.

  4. Generalized Fractional Processes with Long Memory and Time Dependent Volatility Revisited

    Directory of Open Access Journals (Sweden)

    M. Shelton Peiris

    2016-09-01

    Full Text Available In recent years, fractionally-differenced processes have received a great deal of attention due to their flexibility in financial applications with long-memory. This paper revisits the class of generalized fractionally-differenced processes generated by Gegenbauer polynomials and the ARMA structure (GARMA with both the long-memory and time-dependent innovation variance. We establish the existence and uniqueness of second-order solutions. We also extend this family with innovations to follow GARCH and stochastic volatility (SV. Under certain regularity conditions, we give asymptotic results for the approximate maximum likelihood estimator for the GARMA-GARCH model. We discuss a Monte Carlo likelihood method for the GARMA-SV model and investigate finite sample properties via Monte Carlo experiments. Finally, we illustrate the usefulness of this approach using monthly inflation rates for France, Japan and the United States.

  5. Revisiting the plant hyperaccumulation criteria to rare plants and earth abundant elements

    Energy Technology Data Exchange (ETDEWEB)

    Branquinho, Cristina [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Campo Grande C2, Piso 4, 1749-016 Lisbon (Portugal) and Universidade Atlantica, Antiga Fabrica da Polvora de Barcarena, 2745-615 Barcarena (Portugal)]. E-mail: cmbranquinho@fc.ul.pt; Serrano, Helena Cristina [Universidade de Lisboa, Museu Nacional de Historia Natural, Jardim Botanico (Portugal); Pinto, Manuel Joao [Universidade de Lisboa, Museu Nacional de Historia Natural, Jardim Botanico (Portugal); Martins-Loucao, Maria Amelia [Universidade de Lisboa, Faculdade de Ciencias, Centro de Ecologia e Biologia Vegetal, Campo Grande C2, Piso 4, 1749-016 Lisbon (Portugal); Universidade de Lisboa, Museu Nacional de Historia Natural, Jardim Botanico (Portugal)

    2007-03-15

    The several established criteria to define a hyperaccumulator plant were applied to a rare and endangered species, Plantago almogravensis, and to the 3rd most abundant element in the earth crust, Al. Using the most common criteria, P. almogravensis undoubtedly is an Al hyperaccumulator plant. If the recent proposed requirements were considered, most of them matching those for a plant to be used in phytoextraction, it can only be considered an unusual accumulator of Al. A discussion is made concerning the several criteria of a hyperaccumulator plant in order to include rare and endemic ones and abundant elements. In ecological terms, the enrichment in Al and Fe observed may account for the differences in the vegetation pattern. Due to the rarity and endangered nature of this plant, the contribution of this work is also relevant for the ecological understanding and the development of conservation options of this endemic species. - Revisiting plant hyperaccumulation criteria.

  6. Polycarbonate crowns for primary teeth revisited: restorative options, technique and case reports.

    Science.gov (United States)

    Venkataraghavan, Karthik; Chan, John; Karthik, Sandhya

    2014-01-01

    Esthetics by definition is the science of beauty - that particular detail of an animate or inanimate object that makes it appealing to the eye. In the modern, civilized, and cosmetically conscious world, well-contoured and well-aligned white teeth set the standard for beauty. Such teeth are not only considered attractive but are also indicative of nutritional health, self esteem, hygienic pride, and economic status. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. Even though researchers have claimed that certain restorations are better than the others, particularly owing to the issues mentioned above, the search for the ideal esthetic restoration for the primary teeth continues. This paper revisits and attempts to reintroduce the full coverage restoration, namely, polycarbonate crown, for use in primary anterior teeth.

  7. Revisiting the age of enlightenment from a collective decision making systems perspective

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, Marko A [Los Alamos National Laboratory; Watkins, Jennifer H [Los Alamos National Laboratory

    2009-01-01

    The ideals of the eighteenth century's Age of Enlightenment are the foundation of modern democracies. The era was characterized by thinkers who promoted progressive social reforms that opposed the long-established aristocracies and monarchies of the time. Prominent examples of such reforms include the establishment of inalienable human rights, self-governing republics, and market capitalism. Twenty-first century democratic nations can benefit from revisiting the systems developed during the Enlightenment and reframing them within the techno-social context of the Information Age. This article explores the application of social algorithms that make use of Thomas Paine's (English: 1737--1809) representatives, Adam Smith's (Scottish: 1723--1790) self-interested actors, and Marquis de Condorcet's (French: 1743--1794) optimal decision making groups. It is posited that technology-enabled social algorithms can better realize the ideals articulated during the Enlightenment.

  8. Polycarbonate crowns for primary teeth revisited: Restorative options, technique and case reports

    Directory of Open Access Journals (Sweden)

    Karthik Venkataraghavan

    2014-01-01

    Full Text Available Esthetics by definition is the science of beauty - that particular detail of an animate or inanimate object that makes it appealing to the eye. In the modern, civilized, and cosmetically conscious world, well-contoured and well-aligned white teeth set the standard for beauty. Such teeth are not only considered attractive but are also indicative of nutritional health, self esteem, hygienic pride, and economic status. Numerous treatment approaches have been proposed to address the esthetics and retention of restorations in primary teeth. Even though researchers have claimed that certain restorations are better than the others, particularly owing to the issues mentioned above, the search for the ideal esthetic restoration for the primary teeth continues. This paper revisits and attempts to reintroduce the full coverage restoration, namely, polycarbonate crown, for use in primary anterior teeth.

  9. Quantification of synovial and erosive changes in rheumatoid arthritis with ultrasound-Revisited

    Energy Technology Data Exchange (ETDEWEB)

    Schueller-Weidekamm, Claudia [Department of Radiology, Medical University of Vienna, Vienna General Hospital, Waehringer Guertel 18-20, A-1090 Vienna (Austria)], E-mail: claudia.schueller-weidekamm@meduniwien.ac.at

    2009-08-15

    Synovitis is a predictive factor of irreversible changes in the joints, tendons, and ligaments in patients with rheumatoid arthritis (RA). Therefore, the early demonstration of reversible, pre-erosive inflammatory features to diagnose RA, the monitoring of disease activity, and the response to therapy are of great importance. Technical developments in ultrasound now allow the quantification of synovitis and erosions, and enable the assessment and follow-up of disease activity. However, both the subjective and objective quantification techniques are associated with different problems. This review article highlights the advantages and disadvantages of sonographic quantification, and revisits the somewhat controversial positions apparent in the current literature. Familiarity with the imaging findings and the scoring systems used to characterize erosive changes are prerequisites for considerably improving the detection and monitoring of synovitis and erosions. The role of ultrasound in the diagnostic approach to RA, particularly in the quantification of synovial and erosive changes, will be explored and the current literature will be reviewed.

  10. Running spectral index from large-field inflation with modulations revisited

    International Nuclear Information System (INIS)

    We revisit large field inflation models with modulations in light of the recent discovery of the primordial B-mode polarization by the BICEP2 experiment, which, when combined with the Planck+WP+highL data, gives a strong hint for additional suppression of the CMB temperature fluctuations at small scales. Such a suppression can be explained by a running spectral index. In fact, it was pointed out by two of the present authors (TK and FT) that the existence of both tensor mode perturbations and a sizable running of the spectral index is a natural outcome of large inflation models with modulations such as axion monodromy inflation. We find that this holds also in the recently proposed multi-natural inflation, in which the inflaton potential consists of multiple sinusoidal functions and therefore the modulations are a built-in feature

  11. Vacuum Ultraviolet Photodissociation and Fourier Transform-Ion Cyclotron Resonance (FT-ICR) Mass Spectrometry: Revisited.

    Science.gov (United States)

    Shaw, Jared B; Robinson, Errol W; Paša-Tolić, Ljiljana

    2016-03-15

    We revisited the implementation of 193 nm ultraviolet photodissociation (UVPD) within the ion cyclotron resonance (ICR) cell of a Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometer. UVPD performance characteristics were examined in the context of recent developments in the understanding of UVPD and in-cell tandem mass spectrometry. Efficient UVPD and photo-ECD of a model peptide and proteins within the ICR cell of a FT-ICR mass spectrometer are accomplished through appropriate modulation of laser pulse timing, relative to ion magnetron motion and the potential applied to an ion optical element upon which photons impinge. It is shown that UVPD yields efficient and extensive fragmentation, resulting in excellent sequence coverage for model peptide and protein cations.

  12. The Davenport Conspiracy Revisited, by Marshall McKusick, Iowa State University Press, Ames

    Directory of Open Access Journals (Sweden)

    Lynne P. Sullivan

    1991-11-01

    Full Text Available All the components of a nineteenth century mystery novel are contained in the Davenport Conspiracy Revisited -- an elusive race of mysterious "Mound Builders", clergymen with flawed characters, pranksters who overestimated their ability to take a joke, a stubborn lawyer, a near deathbed confession -- the only difference is that this is no novel, it actually happened. In this book, McKusick chronicles the circumstances surrounding the discovery by nineteenth century antiquarians of alleged "Mound Builder" artifacts in burial mounds in the Quad Cities area of Iowa and Illinois. The discovery caused considerable debate in the scientific community at the time, and has even recently resurfaced in popular literature concerning early European "invasions" of Americas.

  13. REVISITING THE SCATTERING GREENHOUSE EFFECT OF CO{sub 2} ICE CLOUDS

    Energy Technology Data Exchange (ETDEWEB)

    Kitzmann, D., E-mail: daniel.kitzmann@csh.unibe.ch [Center for Space and Habitability, University of Bern, Sidlerstr. 5, 3012 Bern (Switzerland)

    2016-02-01

    Carbon dioxide ice clouds are thought to play an important role for cold terrestrial planets with thick CO{sub 2} dominated atmospheres. Various previous studies showed that a scattering greenhouse effect by carbon dioxide ice clouds could result in a massive warming of the planetary surface. However, all of these studies only employed simplified two-stream radiative transfer schemes to describe the anisotropic scattering. Using accurate radiative transfer models with a general discrete ordinate method, this study revisits this important effect and shows that the positive climatic impact of carbon dioxide clouds was strongly overestimated in the past. The revised scattering greenhouse effect can have important implications for the early Mars, but also for planets like the early Earth or the position of the outer boundary of the habitable zone.

  14. SUSY effects in $R_b$: revisited under current experimental constraints

    CERN Document Server

    Su, Wei

    2016-01-01

    In this note we revisit the effects of natural SUSY in $R_b$ under current experimental constraints including the LHC Higgs data, the $B$-physics measurements, the dark matter relic density and direct detection limits, as well as the precision electroweak data. We first perform a scan to figure out the currently allowed parameter space of natural SUSY and then display the SUSY effects in $R_b$. We find that although the SUSY parameter space has been severely restrained by current experimental data, natural SUSY can still alter $R_b$ with a magnitude sizable enough to be observed at future $Z$-factories (ILC, CEPC, FCC-ee, Super $Z$-factory) which produce $10^9-10^{12}$ $Z$-bosons.

  15. The population genetics of Trypanosoma cruzi revisited in the light of the predominant clonal evolution model.

    Science.gov (United States)

    Tibayrenc, Michel; Ayala, Francisco J

    2015-11-01

    Comparing the population structure of Trypanosoma cruzi with that of other pathogens, including parasitic protozoa, fungi, bacteria and viruses, shows that the agent of Chagas disease shares typical traits with many other species, related to a predominant clonal evolution (PCE) pattern: statistically significant linkage disequilibrium, overrepresented multilocus genotypes, near-clades (genetic subdivisions somewhat blurred by occasional genetic exchange/hybridization) and "Russian doll" patterns (PCE is observed, not only at the level of the whole species, but also, within the near-clades). Moreover, T. cruzi population structure exhibits linkage with the diversity of several strongly selected genes, with gene expression profiles, and with some major phenotypic traits. We discuss the evolutionary significance of these results, and their implications in terms of applied research (molecular epidemiology/strain typing, analysis of genes of interest, vaccine and drug design, immunological diagnosis) and of experimental evolution. Lastly, we revisit the long-term debate of describing new species within the T. cruzi taxon.

  16. A geopolítica do poder terrestre revisitada The geopolitics of land power revisited

    Directory of Open Access Journals (Sweden)

    Leonel Itaussu Almeida Mello

    1994-12-01

    Full Text Available O pensamento geopolítico do geógrafo inglês Halford Mackind-er é revisitado com três objetivos: a analisar criticamente os conceitos que formam o arcabouço da teoria do poder terrestre; b enfocar à luz dessa teoria a vitória incruenta da potência insular americana sobre a potência continental soviética no âmbito do sistema bipolar da Guerra Fria; c discutir a atualidade ou obsolescência da geopolítica de Mackinder no contexto da "nova ordem mundial" emergente.The goepolitical ideas of the English geographer Halford J. Mackinder are revisited in order to examine the foundations and contemporary relevance, or obsolescence, of his theory of the land power.

  17. Between De Jure and De Facto Statehood: Revisiting the Status of Taiwan

    Directory of Open Access Journals (Sweden)

    Barry Bartmann

    2008-05-01

    Full Text Available This paper revisits the status prospects for Taiwan in light of recent events in Kosovo and Tibet. In both cases, and certainly in Taiwan itself, the long standing contest between claims for self determination and the tenacious defence of the principle of the territorial integrity of states has emerged once again to dominate the analysis of these cases. This contest is particularly dramatic in the divided international response to the independence of Kosovo. In the case of Tibet, widespread international support for Tibet is in sharp contrast to the furious and determined resistance of China. Taiwan’s anomalous status remains that of a legal sovereign state, the Republic of China, enjoying some measure of recognition and formal diplomacy and a de facto state whose international relations are confined to paradiplomatic channels, extensive though they are. The paper considers the prospects for changes in the current anomalous status of the island state.

  18. Revisit to Thermodynamic Relations in the AdS/CMT Models

    CERN Document Server

    Hyun, Seungjoon; Yi, Sang-Heon

    2016-01-01

    Motivated by the recent unified approach to the Smarr-like relation of AdS planar black holes in conjunction with the quasi-local formalism on conserved charges, we revisit the quantum statistical and thermodynamic relations of hairy AdS planar black holes. By extending the previous results, we identify the hairy contribution in the bulk and show that the holographic computation can be improved so that it is consistent with the bulk computation. We argue that the first law can be retained in its universal form while the relation between the on-shell renormalized Euclidean action and its free energy interpretation in gravity may be deformed to contain the hairy contribution in hairy AdS black holes.

  19. SUSY S{sub 4} Multiplication-Sign SU(5) revisited

    Energy Technology Data Exchange (ETDEWEB)

    Hagedorn, Claudia, E-mail: hagedorn@pd.infn.it [Dipartimento di Fisica e Astronomia ' G. Galilei' , Universita di Padova and INFN, Sezione di Padova, Via Marzolo 8, I-35131 Padua (Italy); King, Stephen F., E-mail: king@soton.ac.uk [School of Physics and Astronomy, University of Southampton, Southampton, SO17 1BJ (United Kingdom); Luhn, Christoph, E-mail: christoph.luhn@durham.ac.uk [Institute for Particle Physics Phenomenology, University of Durham, Durham, DH1 3LE (United Kingdom)

    2012-10-22

    Following the recent results from Daya Bay and RENO, which measure the lepton mixing angle {theta}{sub 13}{sup l} Almost-Equal-To 0.15, we revisit a supersymmetric (SUSY) S{sub 4} Multiplication-Sign SU(5) model, which predicts tri-bimaximal (TB) mixing in the neutrino sector with {theta}{sub 13}{sup l} being too small in its original version. We show that introducing one additional S{sub 4} singlet flavon into the model gives rise to a sizable {theta}{sub 13}{sup l} via an operator which leads to the breaking of one of the two Z{sub 2} symmetries preserved in the neutrino sector at leading order (LO). The results of the original model for fermion masses, quark mixing and the solar mixing angle are maintained to good precision. The atmospheric and solar mixing angle deviations from TB mixing are subject to simple sum rule bounds.

  20. Petri net-based scheduling of time constrained single-arm cluster tools with wafer revisiting

    Directory of Open Access Journals (Sweden)

    ZiCheng Liu

    2016-05-01

    Full Text Available It is very difficult to schedule a single-arm cluster tool with wafer revisiting such that wafer residency time constraints are satisfied. This article conducts a study on this challenging problem for a single-arm cluster tool with atomic layer deposition process. With a so-called p-backward strategy being applied, a Petri net model is developed to describe the dynamic behavior of the system. Based on the model, the existence of a feasible schedule is analyzed, schedulability conditions are derived, and scheduling algorithms are presented if there is a schedule. A schedule is obtained by simply setting the robot waiting time if schedulable, and it is very computationally efficient. The obtained schedule is shown to be optimal. Illustrative examples are given to demonstrate the proposed approach.