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Sample records for ii investigating f0

  1. On the universality of the long-/short-range separation in multiconfigurational density-functional theory. II. Investigating f0 actinide species

    NASA Astrophysics Data System (ADS)

    Fromager, Emmanuel; Réal, Florent; Wâhlin, Pernilla; Wahlgren, Ulf; Jensen, Hans Jørgen Aa.

    2009-08-01

    In a previous paper [Fromager et al., J. Chem. Phys. 126, 074111 (2007)], some of the authors proposed a recipe for choosing the optimal value of the μ parameter that controls the long-range/short-range separation of the two-electron interaction in hybrid multiconfigurational self-consistent field short-range density-functional theory (MC-srDFT) methods. For general modeling with MC-srDFT methods, it is clearly desirable that the same universal value of μ can be used for any molecule. Their calculations on neutral light element compounds all yielded μopt=0.4 a.u. In this work the authors investigate the universality of this value by considering "extreme" study cases, namely, neutral and charged isoelectronic f0 actinide compounds (ThO2, PaO2+, UO22+, UN2, CUO, and NpO23+). We find for these compounds that μopt=0.3 a.u. but show that 0.4 a.u. is still acceptable. This is a promising result in the investigation of a universal range separation. The accuracy of the currently best MC-srDFT (μ =0.3 a.u.) approach has also been tested for equilibrium geometries. Though it performs as well as wave function theory and DFT for static-correlation-free systems, it fails in describing the neptunyl (VII) ion NpO23+ where static correlation is significant; bending is preferred at the MC-srDFT (μ =0.3 a.u.) level, whereas the molecule is known to be linear. This clearly shows the need for better short-range functionals, especially for the description of the short-range exchange. It also suggests that the bending tendencies observed in DFT for NpO23+ cannot be fully explained by the bad description of static correlation effects by standard functionals. A better description of the exchange seems to be essential too.

  2. Technique for the perceptual investigation of F0 contours with application to French.

    PubMed

    Delgutte, B

    1978-11-01

    Two experimental techniques were used in this study: (1) an analysis of F0 contours of French sentences containing words likely to express the speaker's attitude (modals, negative, adverbs, quantifiers) and (2) listeners' judgements of the naturalness of synthetic sentences in which the F0 contour was systematically manipulated. The F0 contours were characterized by schematic patterns [J. Vaissière Res. Lab. Electron., Q. Prog. Report No. 115, MIT, 251-262 (1975)]. For all the sentences that were studied, the configurations of patterns frequently observed in the analyzed corpus were judged most natural when synthesized. This result suggests that the features of the F0 contours most relevant to naturalness are preserved in the pattern representation. Three types of patterns were distinguished: (1) a prominent, demarcative pattern (P2); (2) A PROMINENT, NOndemarcative pattern (PE); (3) nonprominent, nondemarcative patterns, A P2 pattern often occurred at the end of a syntactic constituent. Listeners' judgements showed that a P2 at the end of a syntactic constituent is rarely required for naturalness, but a P2 in contradiction to syntax causes unnaturalness. Prominent patterns (P2 or PE) often occurred on negatives, adverbs, and quantifiers. However, the presence or absence of a prominent pattern on these words does not affect naturalness.

  3. Effect Of Calcium Chelators on the Formation and Oxidation of the Slowly Relaxing Reduced Plastoquinone Pool in Calcium-Depleted PSII Membranes. Investigation of the F0 Yield

    SciTech Connect

    Semin, B. K.; Davletshina, L. N.; Bulychev, A. A.; Ivanov, I. I.; Seibert, M.; Rubin, A. B.

    2007-01-01

    The F{sub 0} fluorescence yield in intact photosystem II (PSII), Ca-depleted PSII (PSII(-Ca/NaCl)), and Mn-depleted PSII membranes was measured before and after dim light treatment (1-2 min), using flash-probe fluorescence and fluorescence induction kinetic measurements. The value of F{sub 0} after the light treatment (F{sup '}{sub 0}) was larger than F{sub 0} in dark-adapted PSII membranes and depended on the appearance of the slowly relaxing, reduced plastoquinone pool (t{sub 1/2} = 4 min) formed during preillumination, which was not totally reoxidized before the F{sup '}{sub 0} measurement. In PSII(-Ca/NaCl) such a pool also appeared, but the F{sup '}{sub 0} yield was even higher than in intact PSII membranes. In Mn-depleted PSII membranes, the pool did not form. Interestingly, the yield of F{sup '}{sub 0} in Ca-depleted PSII membranes prepared using chelators (EGTA and citrate) or containing 5 mM EGTA was significantly lower than in PSII(-Ca/NaCl) samples prepared without chelators. These data indicate that chelators inhibit the reduction of QA and QB and formation of the slowly relaxing plastoquinone pool, or alternatively they increase the rate of its oxidation. Such an effect can be explained by coordination of the chelator molecule to the Mn cluster in PSII(-Ca/NaCl) membranes, rather than different amounts of residual Ca{sup 2+} in the membranes (with or without the chelator), since the remaining oxygen-evolving activity ({approx}15%) in PSII(-Ca/NaCl) samples did not depend on the presence of the chelator. Thus, chelators of calcium cations not only have an effect on the EPR properties of the S2 state in PSII(-Ca/NaCl) samples, but can also influence the PSII properties determining the rate of plastoquinone pool reduction and/or oxidation. The effect of some toxic metal cations (Cd, Cu, Hg) on the formation of the slowly relaxing pool in PSII membranes was also studied.

  4. Investigation of Hexadecylphosphocholine (miltefosine) usage in Pegylated liposomal doxorubicin as a synergistic ingredient: In vitro and in vivo evaluation in mice bearing C26 colon carcinoma and B16F0 melanoma.

    PubMed

    Teymouri, Manouchehr; Farzaneh, Hamidreza; Badiee, Ali; Golmohammadzadeh, Shiva; Sadri, Kayvan; Jaafari, Mahmoud Reza

    2015-12-01

    In this investigation, Hexadecylphosphocholine (HePC, miltefosine) was being used as a new ingredient in Pegylated liposomal doxorubicin (PLD) and different aspects of this integration such as its effect on doxorubicin (Dox) release and cell uptake, cytotoxicity of liposomes, in vivo distribution and half-life clearance time of Dox as well as median survival time were illustrated. The liposomal formulations were Pegylated liposomal doxorubicin containing 0, 0.5, 1, 2 and 4% mole ratios of HePC (HePC-PLD) and their respective Dox-free liposomes (HePC-PLs). The cells used were colon carcinoma (C26), adriamycin-resistant breast cancer (MCF-7-ADR), and B16F0 melanoma cell lines, of which C26 and B16F0 cells were exploited for tumoring in BALB/c and C57Bl/6 mice, respectively. In most cases, increase in miltefosine percentage resulted in physically liposomal instability, increased Dox delivery and toxicity and reduced blood half-life of Dox. Overall, HePC 4% -PLD and PLD differed significantly in many respects and it was considered too toxic to be injected at the same dose (15mg Dox/ kg) as PLD. Although HePC 2% -PLD could extend the median survival time marginally in comparison to PLD, the concept of HePC- containing liposomes merits further investigation.

  5. Speaking a foreign language and its effect on F0.

    PubMed

    Järvinen, Kati; Laukkanen, Anne-Maria; Aaltonen, Olli

    2013-07-01

    This study investigated whether speaking a foreign language affects the fundamental frequency (F0) of speech in 16 native Finnish and 14 native English subjects reading a text in Finnish and in English. The speech samples were analyzed for the mean and range of F0. Speaking a foreign language caused a change in F0 for the Finnish subjects, while the result was not as unambiguous for the English subjects. The change in F0 may be a result of adaptation to a certain pitch level in the foreign environment. Experience in using the foreign language did not show significant correlation to the change in F0, which suggests either individual differences in sensitivity to adaptation or difficulty in quantifying the amount of experience.

  6. Do Red Deer Stags (Cervus elaphus) Use Roar Fundamental Frequency (F0) to Assess Rivals?

    PubMed Central

    Garcia, Maxime; Charlton, Benjamin D.; Wyman, Megan T.; Fitch, W. Tecumseh; Reby, David

    2013-01-01

    It is well established that in humans, male voices are disproportionately lower pitched than female voices, and recent studies suggest that this dimorphism in fundamental frequency (F0) results from both intrasexual (male competition) and intersexual (female mate choice) selection for lower pitched voices in men. However, comparative investigations indicate that sexual dimorphism in F0 is not universal in terrestrial mammals. In the highly polygynous and sexually dimorphic Scottish red deer Cervus elaphus scoticus, more successful males give sexually-selected calls (roars) with higher minimum F0s, suggesting that high, rather than low F0s advertise quality in this subspecies. While playback experiments demonstrated that oestrous females prefer higher pitched roars, the potential role of roar F0 in male competition remains untested. Here we examined the response of rutting red deer stags to playbacks of re-synthesized male roars with different median F0s. Our results show that stags’ responses (latencies and durations of attention, vocal and approach responses) were not affected by the F0 of the roar. This suggests that intrasexual selection is unlikely to strongly influence the evolution of roar F0 in Scottish red deer stags, and illustrates how the F0 of terrestrial mammal vocal sexual signals may be subject to different selection pressures across species. Further investigations on species characterized by different F0 profiles are needed to provide a comparative background for evolutionary interpretations of sex differences in mammalian vocalizations. PMID:24386312

  7. Searches for B meson decays to phiphi, phirho, phif_{0}(980), and f_{0}(980)f_{0}(980) final states.

    PubMed

    Aubert, B; Bona, M; Karyotakis, Y; Lees, J P; Poireau, V; Prencipe, E; Prudent, X; Tisserand, V; Garra Tico, J; Grauges, E; Lopez, L; Palano, A; Pappagallo, M; Eigen, G; Stugu, B; Sun, L; Abrams, G S; Battaglia, M; Brown, D N; Cahn, R N; Jacobsen, R G; Kerth, L T; Kolomensky, Yu G; Lynch, G; Osipenkov, I L; Ronan, M T; Tackmann, K; Tanabe, T; Hawkes, C M; Soni, N; Watson, A T; Koch, H; Schroeder, T; Walker, D; Asgeirsson, D J; Fulsom, B G; Hearty, C; Mattison, T S; McKenna, J A; Barrett, M; Khan, A; Blinov, V E; Bukin, A D; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Bondioli, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Martin, E C; Stoker, D P; Abachi, S; Buchanan, C; Gary, J W; Liu, F; Long, O; Shen, B C; Vitug, G M; Yasin, Z; Zhang, L; Sharma, V; Campagnari, C; Hong, T M; Kovalskyi, D; Mazur, M A; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Schalk, T; Schumm, B A; Seiden, A; Wang, L; Wilson, M G; Winstrom, L O; Cheng, C H; Doll, D A; Echenard, B; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Andreassen, R; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Bloom, P C; Ford, W T; Gaz, A; Hirschauer, J F; Nagel, M; Nauenberg, U; Smith, J G; Ulmer, K A; Wagner, S R; Ayad, R; Soffer, A; Toki, W H; Wilson, R J; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Karbach, M; Merkel, J; Petzold, A; Spaan, B; Wacker, K; Kobel, M J; Mader, W F; Nogowski, R; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Playfer, S; Watson, J E; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cecchi, A; Cibinetto, G; Franchini, P; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Santoro, V; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Chaisanguanthum, K S; Morii, M; Marks, J; Schenk, S; Uwer, U; Klose, V; Lacker, H M; Bard, D J; Dauncey, P D; Nash, J A; Panduro Vazquez, W; Tibbetts, M; Behera, P K; Chai, X; Charles, M J; Mallik, U; Cochran, J; Crawley, H B; Dong, L; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gao, Y Y; Gritsan, A V; Guo, Z J; Lae, C K; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Béquilleux, J; D'Orazio, A; Davier, M; Firmino da Costa, J; Grosdidier, G; Höcker, A; Lepeltier, V; Le Diberder, F; Lutz, A M; Pruvot, S; Roudeau, P; Schune, M H; Serrano, J; Sordini, V; Stocchi, A; Wormser, G; Lange, D J; Wright, D M; Bingham, I; Burke, J P; Chavez, C A; Fry, J R; Gabathuler, E; Gamet, R; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Clarke, C K; George, K A; Di Lodovico, F; Sacco, R; Sigamani, M; Cowan, G; Flaecher, H U; Hopkins, D A; Paramesvaran, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Alwyn, K E; Bailey, D; Barlow, R J; Chia, Y M; Edgar, C L; Jackson, G; Lafferty, G D; West, T J; Yi, J I; Anderson, J; Chen, C; Jawahery, A; Roberts, D A; Simi, G; Tuggle, J M; Dallapiccola, C; Li, X; Salvati, E; Saremi, S; Cowan, R; Dujmic, D; Fisher, P H; Koeneke, K; Sciolla, G; Spitznagel, M; Taylor, F; Yamamoto, R K; Zhao, M; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Simard, M; Taras, P; Viaud, F B; Nicholson, H; De Nardo, G; Lista, L; Monorchio, D; Onorato, G; Sciacca, C; Raven, G; Snoek, H L; Jessop, C P; Knoepfel, K J; Losecco, J M; Wang, W F; Benelli, G; Corwin, L A; Honscheid, K; Kagan, H; Kass, R; Morris, J P; Rahimi, A M; Regensburger, J J; Sekula, S J; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Kolb, J A; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Castelli, G; Gagliardi, N; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Del Amo Sanchez, P; Ben-Haim, E; Briand, H; Calderini, G; Chauveau, J; David, P; Del Buono, L; Hamon, O; Leruste, Ph; Ocariz, J; Perez, A; Prendki, J; Sitt, S; Gladney, L; Biasini, M; Covarelli, R; Manoni, E; Angelini, C; Batignani, G; Bettarini, S; Carpinelli, M; Cervelli, A; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Lopes Pegna, D; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Anulli, F; Baracchini, E; Cavoto, G; Del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Jackson, P D; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Renga, F; Voena, C; Ebert, M; Hartmann, T; Schröder, H; Waldi, R; Adye, T; Franek, B; Olaiya, E O; Wilson, F F; Emery, S; Escalier, M; Esteve, L; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; White, R M; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Benitez, J F; Cenci, R; Coleman, J P; Convery, M R; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dunwoodie, W; Field, R C; Gabareen, A M; Gowdy, S J; Graham, M T; Grenier, P; Hast, C; Innes, W R; Kaminski, J; Kelsey, M H; Kim, H; Kim, P; Kocian, M L; Leith, D W G S; Li, S; Lindquist, B; Luitz, S; Luth, V; Lynch, H L; Macfarlane, D B; Marsiske, H; Messner, R; Muller, D R; Neal, H; Nelson, S; O'Grady, C P; Ofte, I; Perazzo, A; Perl, M; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; Wagner, A P; Weaver, M; West, C A; Wisniewski, W J; Wittgen, M; Wright, D H; Wulsin, H W; Yarritu, A K; Yi, K; Young, C C; Ziegler, V; Burchat, P R; Edwards, A J; Majewski, S A; Miyashita, T S; Petersen, B A; Wilden, L; Ahmed, S; Alam, M S; Ernst, J A; Pan, B; Saeed, M A; Zain, S B; Spanier, S M; Wogsland, B J; Eckmann, R; Ritchie, J L; Ruland, A M; Schilling, C J; Schwitters, R F; Drummond, B W; Izen, J M; Lou, X C; Bianchi, F; Gamba, D; Pelliccioni, M; Bomben, M; Bosisio, L; Cartaro, C; Della Ricca, G; Lanceri, L; Vitale, L; Azzolini, V; Lopez-March, N; Martinez-Vidal, F; Milanes, D A; Oyanguren, A; Albert, J; Banerjee, Sw; Bhuyan, B; Choi, H H F; Hamano, K; Kowalewski, R; Lewczuk, M J; Nugent, I M; Roney, J M; Sobie, R J; Gershon, T J; Harrison, P F; Ilic, J; Latham, T E; Mohanty, G B; Band, H R; Chen, X; Dasu, S; Flood, K T; Pan, Y; Pierini, M; Prepost, R; Vuosalo, C O; Wu, S L

    2008-11-14

    We present the results of searches for B decays to charmless final states involving varphi, f_{0}(980), and charged or neutral rho mesons. The data sample corresponds to 384x10;{6} BB[over ] pairs collected with the BABAR detector operating at the PEP-II asymmetric-energy e;{+}e;{-} collider at SLAC. We find no significant signals and determine the following 90% confidence level upper limits on the branching fractions, including systematic uncertainties: B(B;{0}-->varphivarphi)<2.0x10;{-7}, B(B;{+}-->varphirho;{+})<30x10;{-7}, B(B;{0}-->varphirho;{0})<3.3x10;{-7}, B[B;{0}-->varphif_{0}(980)]xB[f_{0}(980)-->pi;{+}pi;{-}]<3.8x10;{-7}, and B[B;{0}-->f_{0}(980)f_{0}(980)]xB[f_{0}(980)-->pi;{+}pi;{-}]xB[f_{0}(980)-->K;{+}K;{-}]<2.3x10;{-7}.

  8. Effects of hearing aid amplification on voice F0 variability in speakers with prelingual hearing loss.

    PubMed

    Lee, Guo-She; Liu, Chialin; Lee, Shao-Hsuan

    2013-08-01

    To investigate the audio-vocal feedback responses of (F0) to hearing amplification in severe-to-profound prelingual hearing loss (SPHL) using power spectral analysis of F0 contour of sustained vowels. Sustained phonations of vowel/a/of seventeen participants with SPHL were acquired with and without hearing-aid amplifications. The vocal intensity was visually fed back to the participants to help controlling the vocal intensity at 65-75 dBA and 85-95 dBA. The F0 contour of the phonations was extracted and submitted to spectral analysis to measure the extent of F0 fluctuations at different frequency ranges. The results showed that both high vocal intensity and hearing-aid amplification significantly improved voice F0 control by reducing the low-frequency fluctuations (low-frequency power, LFP, 0.2-3 Hz) in F0 spectrum. However, the enhanced feedback from higher vocal intensity and/or hearing amplification was not adequate to reduce the LFP to the level of a normal hearing person. Moreover, we found significant and negative correlations between LFP and supra-threshold feedback intensity (phonation intensity - hearing threshold level) for the frequencies of 500-2000 Hz. Increased vocal intensity, as well as hearing-aid amplification, improved voice F0 control by reducing the LFP of F0 spectrum, and the subtle changes in voices could be well explored using spectral analysis of F0. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Intrinsic F0 in tense and lax vowels with special reference to German.

    PubMed

    Fischer-Jørgensen, E

    1990-01-01

    The main purpose of this paper is to show that the observation which is the starting point for almost all attempts at explaining intrinsic fundamental frequency (intrinsic F0) in vowels, i.e. that it is correlated with vowel height (interpreted as tongue height), does not hold if short lax vowels are included, since they have a considerably lower tongue height but practically the same F0 as their corresponding tense counterparts. Section 1 contains a discussion of some explanations of intrinsic F0 and vowel height and a short exposition of its connection with other vowel features. Section 2 gives a survey of the properties of tense and lax vowels based on data from the phonetic literature. Section 3 reports on an investigation of German tense and lax front unrounded vowels, including duration, tongue height, jaw opening, vertical lip opening, formant frequencies, and F0. Section 4 contains a discussion of various possible explanations of the results.

  10. Perception of pitch location within a speaker's F0 range

    NASA Astrophysics Data System (ADS)

    Honorof, Douglas N.; Whalen, D. H.

    2005-04-01

    Fundamental frequency (F0) is used for many purposes in speech, but its linguistic significance is based on its relation to the speaker's range, not its absolute value. While it may be that listeners can gauge a specific pitch relative to a speaker's range by recognizing it from experience, whether they can do the same for an unfamiliar voice is an open question. The present experiment explored that question. Twenty native speakers of English (10 male, 10 female) produced the vowel /opena/ with a spoken (not sung) voice quality at varying pitches within their own ranges. Listeners then judged, without familiarization or context, where each isolated F0 lay within each speaker's range. Correlations were high both for the entire range (0.721) and for the range minus the extremes (0.609). Correlations were somewhat higher when the F0s were related to the range of all the speakers, either separated by sex (0.830) or pooled (0.848), but several factors discussed here may help account for this pattern. Regardless, the present data provide strong support for the hypothesis that listeners are able to locate an F0 reliably within a range without external context or prior exposure to a speaker's voice. .

  11. Torque Generation and Utilization in Motor Enzyme F0F1-ATP Synthase

    PubMed Central

    Usukura, Eiji; Suzuki, Toshiharu; Furuike, Shou; Soga, Naoki; Saita, Ei-ichiro; Hisabori, Toru; Kinosita, Kazuhiko; Yoshida, Masasuke

    2012-01-01

    ATP synthase (F0F1) is made of two motors, a proton-driven motor (F0) and an ATP-driven motor (F1), connected by a common rotary shaft, and catalyzes proton flow-driven ATP synthesis and ATP-driven proton pumping. In F1, the central γ subunit rotates inside the α3β3 ring. Here we report structural features of F1 responsible for torque generation and the catalytic ability of the low-torque F0F1. (i) Deletion of one or two turns in the α-helix in the C-terminal domain of catalytic β subunit at the rotor/stator contact region generates mutant F1s, termed F1(1/2)s, that rotate with about half of the normal torque. This helix would support the helix-loop-helix structure acting as a solid “pushrod” to push the rotor γ subunit, but the short helix in F1(1/2)s would fail to accomplish this task. (ii) Three different half-torque F0F1(1/2)s were purified and reconstituted into proteoliposomes. They carry out ATP-driven proton pumping and build up the same small transmembrane ΔpH, indicating that the final ΔpH is directly related to the amount of torque. (iii) The half-torque F0F1(1/2)s can catalyze ATP synthesis, although slowly. The rate of synthesis varies widely among the three F0F1(1/2)s, which suggests that the rate reflects subtle conformational variations of individual mutants. PMID:22128167

  12. Reaction time of voluntary modulations in voice F0 during sustained pitch vocalizations

    NASA Astrophysics Data System (ADS)

    Bauer, Jay J.; Larson, Charles R.; Eckstein, Kathryn C.

    2002-05-01

    In an attempt to more clearly understand the neural control of voice, a reaction time study was designed to investigate how rapidly normal subjects, i.e., nontrained singers, can voluntarily increase or decrease their voice fundamental frequency (F0) during sustained vocalizations when cued with a 1000-Hz auditory tone stimulus. Results revealed that overall reaction times (RTs) (F=21.9, df=2, 150, p=0.01) for upward F0 modulations occurred faster (range: 138-176 ms) than downward responses (range: 196-234 ms). In contrast to the reaction time findings, slightly higher peak velocities were observed for downward responses compared to upward responses. Shorter RTs observed for F0 elevation are therefore possibly related to central mechanisms involved in the planning of or execution of the direction in which F0 is to be modulated instead of muscle biomechanics. The fastest RTs obtained from the present study (138 ms) are slightly longer than the reflex latencies of the initial pitch-shift reflex response (100-130 ms) [Burnett, J. Acoust. Soc. Am. 103 (1998)], and provide additional evidence that subjects normally respond to inadvertent changes in their voice F0 with a fast, but limited reflex, followed by a secondary voluntary response. [Research supported by NIH Grant No. DC07264.

  13. The Relationship of Vocal Loudness Manipulation to Prosodic F0 and Durational Variables in Healthy Adults

    ERIC Educational Resources Information Center

    Watson, Peter J.; Hughes, Deanna

    2006-01-01

    This investigation was motivated by observations that when persons with dysarthria increase loudness their speech improves. Some studies have indicated that this improvement may be related to an increase of prosodic variation. Studies have reported an increase of fundamental frequency (F0) variation with increased loudness, but there has been no…

  14. Deltapsi and DeltapH are equivalent driving forces for proton transport through isolated F(0) complexes of ATP synthases.

    PubMed

    Wiedenmann, Alexander; Dimroth, Peter; von Ballmoos, Christoph

    2008-10-01

    The membrane-embedded F(0) part of ATP synthases is responsible for ion translocation during ATP synthesis and hydrolysis. Here, we describe an in vitro system for measuring proton fluxes through F(0) complexes by fluorescence changes of the entrapped fluorophore pyranine. Starting from purified enzyme, the F(0) part was incorporated unidirectionally into phospholipid vesicles. This allowed analysis of proton transport in either synthesis or hydrolysis direction with Deltapsi or DeltapH as driving forces. The system displayed a high signal-to-noise ratio and can be accurately quantified. In contrast to ATP synthesis in the Escherichia coli F(1)F(0) holoenzyme, no significant difference was observed in the efficiency of DeltapH or Deltapsi as driving forces for H(+)-transport through F(0). Transport rates showed linear dependency on the driving force. Proton transport in hydrolysis direction was about 2400 H(+)/(s x F(0)) at Deltapsi of 120 mV, which is approximately twice as fast as in synthesis direction. The chloroplast enzyme was faster and catalyzed H(+)-transport at initial rates of 6300 H(+)/(s x F(0)) under similar conditions. The new method is an ideal tool for detailed kinetic investigations of the ion transport mechanism of ATP synthases from various organisms.

  15. A comparison of high precision F0 extraction algorithms for sustained vowels.

    PubMed

    Parsa, V; Jamieson, D G

    1999-02-01

    Perturbation analysis of sustained vowel waveforms is used routinely in the clinical evaluation of pathological voices and in monitoring patient progress during treatment. Accurate estimation of voice fundamental frequency (F0) is essential for accurate perturbation analysis. Several algorithms have been proposed for fundamental frequency extraction. To be appropriate for clinical use, a key consideration is that an F0 extraction algorithm be robust to such extraneous factors as the presence of noise and modulations in voice frequency and amplitude that are commonly associated with the voice pathologies under study. This work examines the performance of seven F0 algorithms, based on the average magnitude difference function (AMDF), the input autocorrelation function (AC), the autocorrelation function of the center-clipped signal (ACC), the autocorrelation function of the inverse filtered signal (IFAC), the signal cepstrum (CEP), the Harmonic Product Spectrum (HPS) of the signal, and the waveform matching function (WM) respectively. These algorithms were evaluated using sustained vowel samples collected from normal and pathological subjects. The effect of background noise and of frequency and amplitude modulations on these algorithms was also investigated, using synthetic vowel waveforms.

  16. Interactive Digital Image Processing Investigation. Phase II.

    DTIC Science & Technology

    1980-04-01

    International Business Machines Corporation WORK UNIT NUMBERS La Federal Systems Division 18100 Frederick Pike naltber b _rg Maryland 2Q760 11...Radiance Versus Wavelength X. 6.2-2 Operation of a Scanning Sensor 6-6 6.2-3 Multispectral Scanner Measurements - Channel 1 6-7 6.2-4 Multispectral...contains recommendations for further work based on the results S of the present study. L. Ii tii iU 1- -i - " - • I1 --. LI I J-- - ----- t [ [ Section 2

  17. Current Phase II investigational therapies for insomnia.

    PubMed

    Zisapel, Nava

    2015-03-01

    Insomnia is typified by a difficulty in sleep initiation, maintenance and/or quality (non-restorative sleep) resulting in significant daytime distress. This review summarizes the available efficacy and safety data for drugs currently in the pipeline for treating insomnia. Specifically, the authors performed MEDLINE and internet searches using the keywords 'Phase II' and 'insomnia'. The drugs covered target GABAA (zaleplon-CR, lorediplon, EVT-201), orexin (filorexant, MIN-202), histamine-H1 (LY2624803), serotonin 5-HT2A (ITI-007), melatonin/serotonin5-HT1A (piromelatine) and melatonin (indication expansions of prolonged-release melatonin and tasimelteon for pediatric sleep and circadian rhythm disorders) receptors. Low-priced generic environments and high development costs limit the further development of drugs that treat insomnia. However, the bidirectional link between sleep and certain comorbidities may encourage development of specific drugs for comorbid insomnia. New insomnia therapies will most likely move away from GABAAR receptors' modulation to more subtle neurological pathways that regulate the sleep-wake cycle.

  18. Development and Perceptual Evaluation of Amplitude-Based F0 Control in Electrolarynx Speech

    ERIC Educational Resources Information Center

    Saikachi, Yoko; Stevens, Kenneth N.; Hillman, Robert E.

    2009-01-01

    Purpose: Current electrolarynx (EL) devices produce a mechanical speech quality that has been largely attributed to the lack of natural fundamental frequency (F0) variation. In order to improve the quality of EL speech, in the present study the authors aimed to develop and evaluate an automatic F0 control scheme, in which F0 was modulated based on…

  19. Development and Perceptual Evaluation of Amplitude-Based F0 Control in Electrolarynx Speech

    ERIC Educational Resources Information Center

    Saikachi, Yoko; Stevens, Kenneth N.; Hillman, Robert E.

    2009-01-01

    Purpose: Current electrolarynx (EL) devices produce a mechanical speech quality that has been largely attributed to the lack of natural fundamental frequency (F0) variation. In order to improve the quality of EL speech, in the present study the authors aimed to develop and evaluate an automatic F0 control scheme, in which F0 was modulated based on…

  20. Investigations in Marine Chemistry: Salinity II.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.

    Presented is a science activity in which the student investigates methods of calibration of a simple conductivity meter via a hands-on inquiry technique. Conductivity is mathematically compared to salinity using a point slope formula and graphical techniques. Sample solutions of unknown salinity are provided so that the students can sharpen their…

  1. Managing changes during a clinical investigation, Part II.

    PubMed

    Donawa, Maria

    2003-10-01

    What are the European requirements for managing changes that may occur during a clinical investigation? Part II of this article discusses these requirements and the development of a standard operating procedure to help ensure consistent compliance.

  2. Search for the decay of a charged B meson to a charged rho meson and a f0(980) meson

    NASA Astrophysics Data System (ADS)

    Yasin, Zafar

    A search for the decay of B+ meson to rho +f0(980) is presented, using a sample of approximately 465 +/- 5 million BB¯ events (423.5 fb-1 of data) collected with the BABAR detector at the PEP-II asymmetric e+ e- collider at SLAC National Accelerator Laboratory. The following upper limit for the branching fraction at 90% confidence level is obtained: B (B+ → rho+ f0) x B (f0 → pipi) < 1.2 x 10 -6, representing an improvement compared to the previous result.

  3. Antimelanogenic, Antioxidant and Antiproliferative Effects of Antrodia camphorata Fruiting Bodies on B16-F0 Melanoma Cells

    PubMed Central

    Wang, Jyh-Jye; Wu, Chih-Chung; Lee, Chun-Lin; Hsieh, Shu-Ling; Chen, Jin-Bor; Lee, Chu-I

    2017-01-01

    Antrodia camphorata is a fungus that is endemic to Taiwan, and its fruiting body has been used as a folk medicine for the prevention or treatment of diverse diseases. The present study is aimed at investigating the antimelanogenesis and antioxidation effect of the ethanolic extract of Antrodia camphorata fruiting body (EE-AC), as well as its antiproliferation effects in B16-F0 melanoma cells. Regarding antimelanogenic effects, EE-AC had effective cupric ions reducing capacity and expressed more potent inhibitory effect than kojic acid on mushroom tyrosinase activity. Moreover, EE-AC significantly inhibited cellular tyrosinase activity and the melanin content in B16-F0 cells at 12.5 μg/mL concentration without cell toxicities. Regarding antioxidant effects, EE-AC exhibited potent DPPH radical- and SOD-like-scavenging activities. Regarding antiproliferative effects, EE-AC exhibited a selective cytotoxic effect and markedly inhibited the migration ability of B16-F0 cells. EE-AC increased the population of B16-F0 cells at sub-G1 phase of the cell cycle. EE-AC also caused the increase of early apoptotic cells and chromatin condensation, which indicated the apoptotic effects in B16-F0 cells. We demonstrated that EE-AC possessed antimelanogenic, antioxidant and anti-skin cancer actions. The results would contribute to the development and application of cosmetics, healthy food and pharmaceuticals. PMID:28125738

  4. Antimelanogenic, Antioxidant and Antiproliferative Effects of Antrodia camphorata Fruiting Bodies on B16-F0 Melanoma Cells.

    PubMed

    Wang, Jyh-Jye; Wu, Chih-Chung; Lee, Chun-Lin; Hsieh, Shu-Ling; Chen, Jin-Bor; Lee, Chu-I

    2017-01-01

    Antrodia camphorata is a fungus that is endemic to Taiwan, and its fruiting body has been used as a folk medicine for the prevention or treatment of diverse diseases. The present study is aimed at investigating the antimelanogenesis and antioxidation effect of the ethanolic extract of Antrodia camphorata fruiting body (EE-AC), as well as its antiproliferation effects in B16-F0 melanoma cells. Regarding antimelanogenic effects, EE-AC had effective cupric ions reducing capacity and expressed more potent inhibitory effect than kojic acid on mushroom tyrosinase activity. Moreover, EE-AC significantly inhibited cellular tyrosinase activity and the melanin content in B16-F0 cells at 12.5 μg/mL concentration without cell toxicities. Regarding antioxidant effects, EE-AC exhibited potent DPPH radical- and SOD-like-scavenging activities. Regarding antiproliferative effects, EE-AC exhibited a selective cytotoxic effect and markedly inhibited the migration ability of B16-F0 cells. EE-AC increased the population of B16-F0 cells at sub-G1 phase of the cell cycle. EE-AC also caused the increase of early apoptotic cells and chromatin condensation, which indicated the apoptotic effects in B16-F0 cells. We demonstrated that EE-AC possessed antimelanogenic, antioxidant and anti-skin cancer actions. The results would contribute to the development and application of cosmetics, healthy food and pharmaceuticals.

  5. F0 discrimination interference: Effects of resolved tone complexes and noise on fundamental frequency discrimination of unresolved complex tones

    NASA Astrophysics Data System (ADS)

    Gockel, Hedwig; Carlyon, Robert P.; Plack, Christopher J.

    2003-04-01

    F0 discrimination of a 400-ms complex tone with only unresolved components (``target'') was investigated in the absence and presence of a synchronously gated resolved complex tone (``interferer''). The target and the interferer were bandpass filtered from 1375-15000 Hz and 125-625 Hz, respectively. In a 2I-2AFC task, listeners indicated the interval containing the target with the higher pitch. The nominal F0 of the target was 88 Hz; that of the interferer was constant across the two intervals and was either 88 Hz or increased by various amounts. Although the target and interferer were in well-separated frequency regions, performance (percent correct) dropped by about 16% when the interferer's F0 was 88 Hz. The impairment was halved when the interferer's F0 was 10% higher than that of the target, and almost eliminated when it was 30% higher. Increasing the level of a 1375-Hz low-pass-filtered noise, gated synchronously with the target and the interferer (F0 equaled 88 Hz), improved performance, further demonstrating that the deterioration produced by the resolved complex was not due to peripheral masking. The results are consistent with a form of across-frequency interference at the level of pitch perception. [Work supported by EPSRC Grant GR/R65794/01.

  6. f_0(500), f_0(980), and a_0(980) production in the χ _{c1} → η π ^+π ^- reaction

    NASA Astrophysics Data System (ADS)

    Liang, Wei-Hong; Xie, Ju-Jun; Oset, Eulogio

    2016-12-01

    We study the χ _{c1} → η π ^+ π ^- decay, paying attention to the production of f_0(500), f_0(980), and a_0(980) from the final state interaction of pairs of mesons that can lead to these three mesons in the final state, which is implemented using the chiral unitary approach. Very clean and strong signals are obtained for the a_0(980) excitation in the η π invariant mass distribution and for the f_0(500) in the π ^+ π ^- mass distribution. A smaller, but also clear signal for the f_0(980) excitation is obtained. The results are contrasted with experimental data and the agreement found is good, providing yet one more test in support of the picture where these resonances are dynamically generated from the meson-meson interaction.

  7. Superconductivity in a new layered bismuth oxyselenide: LaO(0.5)F(0.5)BiSe₂.

    PubMed

    Krzton-Maziopa, A; Guguchia, Z; Pomjakushina, E; Pomjakushin, V; Khasanov, R; Luetkens, H; Biswas, P K; Amato, A; Keller, H; Conder, K

    2014-05-28

    We report superconductivity at T(c) ≈ 2.6 K in a new layered bismuth oxyselenide LaO(0.5)F(0.5)BiSe2 with the ZrCuSiAs-type structure composed of alternating superconducting BiSe2 and blocking LaO layers. The superconducting properties of LaO(0.5)F(0.5)BiSe2 were investigated by means of dc magnetization, resistivity and muon-spin rotation experiments, revealing the appearance of bulk superconductivity with a rather large superconducting volume fraction of ≈ 70% at 1.8 K.

  8. Speech perception with F0mod, a cochlear implant pitch coding strategy.

    PubMed

    Francart, Tom; Osses, Alejandro; Wouters, Jan

    2015-06-01

    The fundamental frequency modulation (F0mod) sound processing strategy was developed to improve pitch perception with cochlear implants. In previous work it has been shown to improve performance in a number of pitch-related tasks such as pitch ranking, familiar melody identification, and Mandarin Chinese tone identification. The objective of the current study was to compare speech perception with F0mod and the standard clinical advanced combination encoder (ACE) strategy. Seven cochlear-implant listeners were recruited from the clinical population of the University Hospital Leuven. F0mod was implemented on a real-time system. Speech recognition in quiet and noise was measured for seven cochlear-implant listeners, comparing F0mod with ACE, using three different Dutch-language speech materials. Additionally the F0 estimator used was evaluated physically, and pitch ranking performance was compared between F0mod and ACE. Immediately after switch-on of the F0mod strategy, speech recognition in quiet and noise were similar for ACE and F0mod, for four out of seven listeners. The remaining three listeners were subjected to a short training protocol with F0mod, after which their performance was reassessed, and a significant improvement was found. As F0mod improves pitch perception, for the seven subjects tested it did not interfere with speech recognition in quiet and noise, and has a low computational complexity, it seems promising for implementation in a clinical sound processor.

  9. Coupling of proton flow to ATP synthesis in Rhodobacter capsulatus: F(0)F(1)-ATP synthase is absent from about half of chromatophores.

    PubMed

    Feniouk, B A; Cherepanov, D A; Junge, W; Mulkidjanian, A Y

    2001-11-01

    F(0)F(1)-ATP synthase (H(+)-ATP synthase, F(0)F(1)) utilizes the transmembrane protonmotive force to catalyze the formation of ATP from ADP and inorganic phosphate (P(i)). Structurally the enzyme consists of a membrane-embedded proton-translocating F(0) portion and a protruding hydrophilic F(1) part that catalyzes the synthesis of ATP. In photosynthetic purple bacteria a single turnover of the photosynthetic reaction centers (driven by a short saturating flash of light) generates protonmotive force that is sufficiently large to drive ATP synthesis. Using isolated chromatophore vesicles of Rhodobacter capsulatus, we monitored the flash induced ATP synthesis (by chemoluminescence of luciferin/luciferase) in parallel to the transmembrane charge transfer through F(0)F(1) (by following the decay of electrochromic bandshifts of intrinsic carotenoids). With the help of specific inhibitors of F(1) (efrapeptin) and of F(0) (venturicidin), we decomposed the kinetics of the total proton flow through F(0)F(1) into (i) those coupled to the ATP synthesis and (ii) the de-coupled proton escape through F(0). Taking the coupled proton flow, we calculated the H(+)/ATP ratio; it was found to be 3.3+/-0.6 at a large driving force (after one saturating flash of light) but to increase up to 5.1+/-0.9 at a smaller driving force (after a half-saturating flash). From the results obtained, we conclude that our routine chromatophore preparations contained three subsets of chromatophore vesicles. Chromatophores with coupled F(0)F(1) dominated in fresh material. Freezing/thawing or pre-illumination in the absence of ADP and P(i) led to an increase in the fraction of chromatophores with at least one de-coupled F(0)(F(1)). The disclosed fraction of chromatophores that lacked proton-conducting F(0)(F(1)) (approx. 40% of the total amount) remained constant upon these treatments.

  10. Investigation of lead(II) uptake by Bacillus thuringiensis 016.

    PubMed

    Chen, Zhi; Pan, Xiaohong; Chen, Hui; Lin, Zhang; Guan, Xiong

    2015-11-01

    In this work, we investigated the lead(II) biosorption mechanism of Bacillus thuringiensis (Bt) 016 through batch and microscopic experiments. We found that the maximum lead(II) biosorption capacity of Bt 016 was 164.77 mg/g (dry weight). The pH value could affect the biosorption of lead(II) in a large extent. Fourier transform infrared analyses and selective passivation experiments suggested that the carboxyl, amide and phosphate functional groups of Bt 016 played an important role in lead(II) biosorption. Scanning electron microscopy observation showed that noticeable lead(II) precipitates were accumulated on bacterial surfaces. Further transmission electron microscopy thin section analysis coupled with energy dispersive X-ray spectroscopy as well as selected area electron diffraction indicated that lead(II) immobilized on the bacteria could be transformated into random-shaped crystalline lead-containing minerals eventually. This work provided a new insight into lead(II) uptake of Bt, highlighting the potential of Bt in the restoration of lead(II) contaminated repositories.

  11. Accent detection is a slippery slope: Direction and rate of F0 change drives listeners’ comprehension

    PubMed Central

    Isaacs, Angela M.; Watson, Duane G.

    2011-01-01

    The present study tests whether listeners use F0, duration, or some combination of the two to identify the presence of an accented word in a short discourse. Participants’ eye movements to previously mentioned and new objects were monitored as participants listened to instructions to move objects in a display. The name of the target object on critical trials was resynthesized from naturally-produced utterances so that it had either high or low F0 and either long or short duration. Fixations to the new object were highest when there was a steep rise in F0. Fixations to the previously mentioned object were highest when there was a steep drop in F0. These results suggest that listeners use F0 slope to make decisions about the presence of an accent, and that F0 and duration by themselves do not solely determine accent interpretation. PMID:22096265

  12. B→f0(980)K decays and subleading corrections

    NASA Astrophysics Data System (ADS)

    Cheng, Hai-Yang; Yang, Kwei-Chou

    2005-03-01

    The decay B→f0(980)K is studied within the framework of QCD factorization and the two-quark scenario for f0(980). There are two distinct penguin contributions and their interference depends on the unknown mixing angle θ of strange and nonstrange quark contents of f0(980): destructive for 0<θ<π/2 and constructive for π/2<θ<π. The QCD sum-rule method is applied to evaluate the leading-twist light-cone distribution amplitudes and the scalar decay constant of f0. We conclude that the short-distance approach is not adequate to explain the observed large rates of f0K- and f0K¯0. Among many possible subleading corrections, we study and estimate the contributions from the three-parton Fock states of the f0 and from the intrinsic gluon inside the B meson. It is found that the spectator gluon of the B meson may play an eminent role for the enhancement of f0(980)K. We point out that if f0(980) is a four-quark state as widely perceived, there will exist extra diagrams contributing to B→f0(980)K. However, in practice it is difficult to make quantitative predictions based on the four-quark picture for f0(980) as it involves additional nonfactorizable contributions that are difficult to estimate and the calculations of the decay constant and form factors of f0(980) are beyond the conventional quark model.

  13. Scalar meson f0(980) in heavy-meson decays

    NASA Astrophysics Data System (ADS)

    El-Bennich, B.; Leitner, O.; Dedonder, J.-P.; Loiseau, B.

    2009-04-01

    A phenomenological analysis of the scalar meson f0(980) is performed that relies on the quasi-two-body decays D and Ds→f0(980)P, with P=π, K. The two-body branching ratios are deduced from experimental data on D or Ds→πππ, Kmacr Kπ and from the f0(980)→π+π- and f0(980)→K+K- branching fractions. Within a covariant quark model, the scalar form factors for the transitions D and Ds→f0(980) are computed. The weak D decay amplitudes, in which these form factors enter, are obtained in the naive factorization approach assuming a q qmacr state for the scalar and pseudoscalar mesons. They allow to extract information on the f0(980) wave function in terms of u umacr , d dmacr , and s smacr pairs as well as on the mixing angle between the strange and nonstrange components. The weak transition form factors are modeled by the one-loop triangular diagram using two different relativistic approaches: covariant light-front dynamics and dispersion relations. We use the information found on the f0(980) structure to evaluate the scalar and vector form factors in the transitions D and Ds→f0(980), as well as to make predictions for B and Bs→f0(980), for the entire kinematically allowed momentum range of q2.

  14. Pion scalar form factor with correct mass and width of scalar mesons f0(500 ) and f0(980 )

    NASA Astrophysics Data System (ADS)

    Dubnicka, Stanislav; Dubnickova, Anna Zuzana; Kamiński, Robert; Liptaj, Andrej

    2016-09-01

    Construction of the pion scalar isoscalar form factor Γπ(t ) in the elastic region, with an emphasis on the values of the S-wave isoscalar π π scattering length a00 and the quadratic pion scalar radius ⟨r2⟩sπ to be in conformity with predictions of the chiral perturbation theory, is presented. It is based on a precise S-wave isoscalar π π scattering phase shift generated by dispersive analysis of experimental data with and imposed crossing symmetry condition. The final result for values of the f0(500 ) scalar meson mass and width is mσ=(487 ±31 ) MeV ; Γσ=(542 ±60 ) MeV and for values of the f0(980 ) scalar meson mass and width is mf (980 )=(988 ±78 ) MeV ; Γf (980 )=(97 ±29 ) MeV . The f0(500 ) scalar meson parameters are compatible with the results from dispersive analyses of the BERN and MADRID/CRACOW groups to be considered now as the most reliable values of the f0(500 ) scalar meson parameters, though in presented analysis another, unusual way has been applied. The f0(980 ) meson parameters agree well with values given by the Particle Data Group.

  15. Perception of relative location of F0 within the speaking range

    NASA Astrophysics Data System (ADS)

    Honorof, Douglas N.; Whalen, D. H.

    2003-10-01

    It has been argued that intrinsic fundamental frequency (IF0) is an automatic consequence of vowel production [Whalen et al., J. Phon. 27, 125-142 (1999)], yet speakers do not adjust F0 so as to overcome IF0. It may be that so adjusting F0 would distort information about F0 range-information important to the interpretation of F0. Therefore, a speech production/perception experiment was designed to determine whether listeners can perceive position within a speaker-specific F0 range on the basis of isolated tokens. Ten male and ten female adult native speakers of US English were recorded speaking (not singing) the vowel /a/ on eight different pitches spaced throughout speaker-specific ranges. Recordings were randomized across speakers. Naive listeners made pitch-magnitude estimates of the location of F0 relative to each speaker's range. Preliminary results show correlations between estimated and actual location within the range. Adjusting F0 to compensate for IF0 differences between vowels would seem to obscure voice quality in such a way as to make it difficult for the listener to recover relative F0, requiring a greater perceptual adjustment than simply normalizing for IF0. [Work supported by NIH Grant No. DC02717.

  16. 26 CFR 1.904(f)-0 - Outline of regulation provisions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 9 2010-04-01 2010-04-01 false Outline of regulation provisions. 1.904(f)-0 Section 1.904(f)-0 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED... which gain would not otherwise be recognized. (i) Recognition of gain to the extent of the...

  17. Perception of Mandarin Lexical Tones when F0 Information Is Neutralized

    ERIC Educational Resources Information Center

    Liu, Siyun; Samuel, Arthur G.

    2004-01-01

    In tone languages, the identity of a word depends on its tone pattern as well as its phonetic structure. The primary cue to tone identity is the fundamental frequency (F0) contour. Two experiments explore how listeners perceive Mandarin monosyllables in which all or part of the F0 information has been neutralized. In Experiment 1, supposedly…

  18. Comparison of Tevatron C0 and F0 Lambertson beam impedance

    SciTech Connect

    James L Crisp and Brian Fellenz

    2003-04-11

    Both the longitudinal and transverse beam impedance measurements for the Tevatron C0 and F0 lambertsons are presented. The C0 lambertsons were designed for circulating beam to travel through the 1 inch high by 6 inch wide field region. In the F0 lambertsons, circulating beam passes through the 2.5 inch high by 4 in ch wide field free region. The more recently designed F0 lambertsons have significantly less impedance than the older C0 lambertsons. Transverse impedance scales as one over the diameter of the aperture cubed. The three C0 style lambertsons were recently removed from the Tevatron. Four of the F0 lambertsons remain. Nine of the F0 style lambertsons are in the Main Injector and three more are required for Numi.

  19. Use of B→J/ψ f0 decays to discern the qq or tetraquark nature of scalar mesons.

    PubMed

    Stone, Sheldon; Zhang, Liming

    2013-08-09

    We consider the relative decay rates of B(0) and Bs(0) mesons into a J/ψ plus a light scalar meson, either the f0(500) (σ) or the f0(980). We show that it is possible to distinguish between the quark content of the scalars being quark-antiquark or tetraquark by measuring specific ratios of decay rates. Using current data we determine the ratio of form factors in Bs(0)→J/ψf0(980) with respect to B(0)→J/ψf0(500) decays to be 0.99(-0.04)(+0.13) at a four-momentum transfer squared equal to the mass of the J/ψ meson squared. In the case where these light mesons are considered to be quark-antiquark states, we give a determination of the mixing angle between strange and light quark states of less than 29° at 90% confidence level. We also discuss the use of a similar ratio to investigate the structure of other isospin singlet states.

  20. INSPEC SDI Investigation, 1967-1969. Volume II.

    ERIC Educational Resources Information Center

    Clague, P.

    Volume II of this five volume investigation of the INSPEC SDI system contains discussions of the following topics: (1) Composition of user and control groups and the information use habits of users and controls, (2) thesaurus development and document indexing, (3) problems of printing notification cards and assessing numbers required for each…

  1. Effects of envelope-vocoder processing on F0 discrimination and concurrent-vowel identification.

    PubMed

    Qin, Michael K; Oxenham, Andrew J

    2005-10-01

    The aim of this study was to examine the effects of envelope-vocoder sound processing on listeners' ability to discriminate changes in fundamental frequency (F0) in anechoic and reverberant conditions and on their ability to identify concurrent vowels based on differences in F0. In the first experiment, F0 difference limens (F0DLs) were measured as a function of number of envelope-vocoder frequency channels (1, 4, 8, 24, and 40 channels, and unprocessed) in four normal-hearing listeners, with degree of simulated reverberation (no, mild, and severe reverberation) as a parameter. In the second experiment, vowel identification was measured as a function of the F0 difference between two simultaneous vowels in six normal-hearing listeners, with the number of vocoder channels (8 and 24 channels, and unprocessed) as a parameter. Reverberation was detrimental to F0 discrimination in conditions with fewer numbers of vocoder channels. Despite the reasonable F0DLs (<1 semitone) with 24- and 8-channel vocoder processing, listeners were unable to benefit from F0 differences between the competing vowels in the concurrent-vowel paradigm. The overall detrimental effects of vocoder processing are probably are due to the poor spectral representation of the lower-order harmonics. The F0 information carried in the temporal envelope is weak, susceptible to reverberation, and may not suffice for source segregation. To the extent that vocoder processing simulates cochlear implant processing, users of current implant processing schemes are unlikely to benefit from F0 differences between competing talkers when listening to speech in complex environments. The results provide further incentive for finding a way to make the information from low-order, resolved harmonics available to cochlear implant users.

  2. The archaeal cofactor F0 is a light-harvesting antenna chromophore in eukaryotes.

    PubMed

    Glas, Andreas F; Maul, Melanie J; Cryle, Max; Barends, Thomas R M; Schneider, Sabine; Kaya, Emine; Schlichting, Ilme; Carell, Thomas

    2009-07-14

    Archae possess unique biochemical systems quite distinct from the pathways present in eukaryotes and eubacteria. 7,8-Dimethyl-8-hydroxy-5deazaflavin (F(0)) and F(420) are unique deazaflavin-containing coenzyme and methanogenic signature molecules, essential for a variety of biochemical transformations associated with methane biosynthesis and light-dependent DNA repair. The deazaflavin cofactor system functions during methane biosynthesis as a low-potential hydrid shuttle F(420)/F(420)H(2). In DNA photolyase repair proteins, the deazaflavin cofactor is in the deprotonated state active as a light-collecting energy transfer pigment. As such, it converts blue sunlight into energy used by the proteins to drive an essential repair process. Analysis of a eukaryotic (6-4) DNA photolyase from Drosophila melanogaster revealed a binding pocket, which tightly binds F(0). Residues in the pocket activate the cofactor by deprotonation so that light absorption and energy transfer are switched on. The crystal structure of F(0) in complex with the D. melanogaster protein shows the atomic details of F(0) binding and activation, allowing characterization of the residues involved in F(0) activation. The results show that the F(0)/F(420) coenzyme system, so far believed to be strictly limited to the archael kingdom of life, is far more widespread than anticipated. Analysis of a D. melanogaster extract and of a DNA photolyase from the primitive eukaryote Ostreococcus tauri provided direct proof for the presence of the F(0) cofactor also in higher eukaryotes.

  3. Neural-network simulation of tonal categorization based on F0 velocity profiles

    NASA Astrophysics Data System (ADS)

    Gauthier, Bruno; Shi, Rushen; Xu, Yi; Proulx, Robert

    2005-04-01

    Perception studies have shown that by the age of six months, infants show particular response patterns to tones in their native language. The present study focuses on how infants might develop lexical tones in Man- darin. F0 is generally considered the main cue in tone perception. However, F0 patterns in connected speech display extensive contextual variability. Since speech input to infants consists mainly of multi-word utterances, tone learning must involve processes that can effectively resolve variability. In this study we explore the Target Approximation model (Xu and Wang, 2001) which characterizes surface F0 as asymptotic movements toward underlying pitch targets defined as simple linear functions. The model predicts that it is possible to infer underlying pitch targets from the manners of F0 movements. Using production data of three of the speakers from Xu (1997), we trained a self-organizing neural network with both F0 profiles and F0 velocity profiles as input. In the testing phase, velocity profiles yielded far superior categorization than F0 profiles. The results confirm that velocity profiles can effectively abstract away from surface variability and directly reflect underlying articulatory goals. The finding thus points to one way through which infants can successfully derive at phonetic categories from adult speech.

  4. Overview of Prospective Investigation of Pulmonary Embolism Diagnosis II.

    PubMed

    Gottschalk, Alexander; Stein, Paul D; Goodman, Lawrence R; Sostman, H Dirk

    2002-07-01

    The Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) is a prospective multicenter study funded by the National Heart, Lung, and Blood Institute which began recruiting patients in the fall of 2001. It was designed to assess the efficacy of the spiral computed tomographic pulmonary angiogram in patients suspected of having acute pulmonary embolism (PE). In contrast to the original PIOPED study, which used contrast pulmonary angiography as the primary reference test for PE, PIOPED II will use a composite reference test for venous thromboembolism that is based on the ventilation/perfusion lung scan, venous compression ultrasound of the lower extremities, digital subtraction pulmonary angiography, and contrast venography in various combinations to establish the PE status of the patient. New criteria for ventilation/perfusion lung scan diagnosis have been developed for PIOPED II. This article describes the various techniques that will be used, the combination of the composite reference tests that will be used to determine the PE status of the patient, and the PIOPED II diagnostic criteria that will be used for the ventilation/perfusion scan diagnosis of PE in the study. Copyright 2002, Elsevier Science (USA). All rights reserved.

  5. Predictions for ηc → ηπ+π- producing f0(500), f0(980) and a0(980)

    NASA Astrophysics Data System (ADS)

    Debastiani, V. R.; Liang, Wei-Hong; Xie, Ju-Jun; Oset, E.

    2017-03-01

    We perform calculations for the ηc → ηπ+π- decay using elements of SU(3) symmetry to see the weight of different trios of pseudoscalars produced in this decay, prior to the final state interaction of the mesons. After that, the interaction of pairs of mesons, leading finally to ηπ+π-, is done using the chiral unitary approach. We evaluate the π+π- and πη mass distributions and find large and clear signals for f0 (500), f0 (980) and a0 (980) excitation. The reaction is similar to the χc1 → ηπ+π-, which has been recently measured at BESIII and its implementation and comparison with these predictions will be very valuable to shed light on the nature of the low mass scalar mesons.

  6. Mefloquine and new related compounds target the F(0) complex of the F(0)F(1) H(+)-ATPase of Streptococcus pneumoniae.

    PubMed

    Martín-Galiano, Antonio Javier; Gorgojo, Begoña; Kunin, Calvin M; de la Campa, Adela G

    2002-06-01

    The activities of mefloquine (MFL) and related compounds against previously characterized Streptococcus pneumoniae strains carrying defined amino acid substitutions in the c subunit of the F(0)F(1) H(+)-ATPase were studied. In addition, a series of MFL-resistant (Mfl(r)) strains were isolated and characterized. A good correlation was observed between inhibition of growth and inhibition of the membrane-associated F(0)F(1) H(+)-ATPase activity. MFL was about 10-fold more active than optochin and about 200-fold more active than quinine in inhibiting both the growth and the ATPase activities of laboratory pneumococcal strain R6. Mutant strains were inhibited by the different compounds to different degrees, depending on their specific mutations in the c subunit. The resistant strains studied had point mutations that changed amino acid residues in either the c subunit or the a subunit of the F(0) complex. Changes in the c subunit were located in one of the two transmembrane alpha helices: residues M13, G14, G20, M23, and N24 of helix 1 and residues M44, G47, V48, A49, and V57 of helix 2. Changes in the a subunit were also found in either of the transmembrane alpha helices, helix 5 or 6: residue L186 of helix 5 and residues W206, F209, and S214 of helix 6. These results suggest that the transmembrane helices of the c and a subunits interact and that the mutated residues are important for the structure of the F(0) complex and proton translocation.

  7. Mefloquine and New Related Compounds Target the F0 Complex of the F0F1 H+-ATPase of Streptococcus pneumoniae

    PubMed Central

    Martín-Galiano, Antonio Javier; Gorgojo, Begoña; Kunin, Calvin M.; de la Campa, Adela G.

    2002-01-01

    The activities of mefloquine (MFL) and related compounds against previously characterized Streptococcus pneumoniae strains carrying defined amino acid substitutions in the c subunit of the F0F1 H+-ATPase were studied. In addition, a series of MFL-resistant (Mflr) strains were isolated and characterized. A good correlation was observed between inhibition of growth and inhibition of the membrane-associated F0F1 H+-ATPase activity. MFL was about 10-fold more active than optochin and about 200-fold more active than quinine in inhibiting both the growth and the ATPase activities of laboratory pneumococcal strain R6. Mutant strains were inhibited by the different compounds to different degrees, depending on their specific mutations in the c subunit. The resistant strains studied had point mutations that changed amino acid residues in either the c subunit or the a subunit of the F0 complex. Changes in the c subunit were located in one of the two transmembrane α helices: residues M13, G14, G20, M23, and N24 of helix 1 and residues M44, G47, V48, A49, and V57 of helix 2. Changes in the a subunit were also found in either of the transmembrane α helices, helix 5 or 6: residue L186 of helix 5 and residues W206, F209, and S214 of helix 6. These results suggest that the transmembrane helices of the c and a subunits interact and that the mutated residues are important for the structure of the F0 complex and proton translocation. PMID:12019076

  8. Precise determination of the f0(500) and f0(980) parameters in dispersive analysis of the ππ data

    NASA Astrophysics Data System (ADS)

    Kamiński, Robert; Garcia-Martin, R.; Pelaez, J. R.; Ruiz de Elvira, J.

    2013-01-01

    Use of the new and precise dispersive equations with imposed crossing symmetry condition to solve the long-standing puzzle in the parameters of the f0(500), as well as the f0(980) is presented. This puzzle is finally being settled thanks to analyzes carried out during the last years [J. Beringer et al. (Particle Data Group), Phys. Rev. D86, (2012) 010001]. In this report we show how our very recent dispersive data analysis allowed for a precise and model independent determination of the amplitudes for the S, P, D and F waves [R. Garcia-Martin, R. Kaminski, J. R. Pelaez, J. Ruiz de Elvira and F.J. Yndurain, Phys. Rev. D83, (2011) 074004; R. Garcia-Martin, R. Kamiński, J.R. Pelaez and J. Ruiz de Elvira, Phys. Rev. Lett. 107, (2011) 072001; R. Kamiński, Phys. Rev. D83, (2011) 076008]. Especially we present that the analytic continuation of once subtracted dispersion relations for the S 0 wave to the complex energy plane leads to very precise results for the f0(500) pole: √{s}=457-13+14-i279-7+11 MeV and for the f0(980) pole: √{s}=996±7-i25-6+10 MeV. We also mention on first (or one of the first) practical application of presented dispersion relations in refitting and in significant improving of the ππ S-wave amplitudes below 1000 MeV.

  9. No indication of f0(1370) in ππ phase shift analyses

    NASA Astrophysics Data System (ADS)

    Ochs, Wolfgang

    2010-08-01

    The scalar meson f0(1370)—indicated in particular in the low energy pp¯→3 body reactions—is a crucial element in certain schemes of the scalar meson spectroscopy including glueballs. The most definitive results can be obtained from elastic and inelastic ππ phase shift analyses using the constraints from unitarity where the discrete ambiguities can be identified and resolved. We reconsider the phase shift analyses for π+π-→π+π-, π0π0, KK¯, ηη. While a clear resonance signal for f0(1500) in the resp. Argand diagrams is seen in all channels above a large "background" from f0(600) there is no clear signal of a second resonance "f0(1370)" in this mass range in any reaction, at the level of ˜10% branching ratio into ππ.

  10. Mechanically driven proton conduction in single delta-free F0F1-ATPase.

    PubMed

    Xiaolong, Liu; Xiaoai, Zhang; Yuanbo, Cui; Jiachang, Yue; Zhiyong, Luo; Peidong, Jiang

    2006-09-01

    In order to observe mechanically driven proton flux in F(0)F(1)-ATPase coupled with artificial driven rotation on F(1) simultaneously, a double channel observation system was established. An artificial delta-free F(0)F(1)-ATPase was constructed with alpha(3), beta(3), epsilon, gamma, and c(n) subunits as rotator and a, b(2) as stator. The chromatophore was immobilized on the glass surface through biotin-streptavidin-biotin system, and the magnetic bead was attached to the beta subunit of delta-free F(0)F(1)-ATPase. The mechanically driven proton flux was indicated by the fluorescence intensity change of fluorescein reference standard (F1300) and recorded by a cooled digital CCD camera. The mechanochemical coupling stoichiometry between F(0) and F(1) is about 4.15 +/- 0.2H(+)/rev when the magnetic field rotated at 0.33 Hz (rps).

  11. A study of the γ ^*-f0(980) transition form factors

    NASA Astrophysics Data System (ADS)

    Kroll, P.

    2017-02-01

    The γ ^*-f0(980) transition form factors are calculated within the QCD factorization framework. The f_0-meson is assumed to be mainly generated through its sbar{s} Fock component. The corresponding spin wave function of the f0(980) meson is constructed and, combined with a model light-cone wave function for this Fock component, used in the calculation of the form factors. In the real-photon limit the results for the transverse form factor are compared to the large momentum-transfer data measured by the BELLE collaboration recently. It turns out that, for the momentum-transfer range explored by BELLE, the collinear approximation does not suffice, power corrections to it, modeled as quark transverse moment effects, seem to be needed. Mixing of the f_0 with the σ (500) is also briefly discussed.

  12. Isospin breaking and f0(980)-a0(980) mixing in the η(1405) → π0f0(980) reaction

    NASA Astrophysics Data System (ADS)

    Aceti, F.; Liang, W. H.; Oset, E.; Wu, J. J.; Zou, B. S.

    2014-06-01

    We make a theoretical study of the η(1405) → π0f0(980) and η(1405) → π0a0(980) reactions to determine the isospin violation and the mixing of the f0(980) and a0(980) resonances. We make use of the chiral unitary approach where these two resonances appear as dynamically generated by the meson-meson interaction provided by chiral Lagrangians. We obtain a very narrow shape for the f0(980) production in agreement with a BES experiment. As to the amount of isospin violation, assuming constant vertices for the primary η(1405) → π0KK̅ and η(1405) → π0π0η production, we find results which are much smaller than found in the experimental BES paper. The problem is solved by using the primary production driven by η' → K*K̅ followed by K∗→ Kπ. Thus, we can predict absolute values for the ratio Γ(π0,π+π-)/Γ(π0,π0η) which are in fair agreement with experiment.

  13. Towards a model-independent determination of the φ -> γ f0 coupling

    NASA Astrophysics Data System (ADS)

    Boglione, M.; Pennington, M. R.

    2003-10-01

    A guide to the composition of the enigmatic f 0(980) and a 0(980) states is their formation in φ-radiative decays. Precision data are becoming available from the KLOE experiment at the DAΦNE machine at Frascati, as well as results from SND and CMD-2 at VEPP-2M at Novosibirsk. We show how the coupling of the f 0(980) to this channel can be extracted from these, independently of the background provided by σ production. To do this we use the fact that the behaviour of both the f 0(980) and σ cannot be determined by these data alone, but is strongly constrained by experimental results from other hadronic processes as required by unitarity. We find that the resulting coupling for the φto γ f_0(980) is ˜ 10^{-4} GeV with a background that is quite unlike that assumed if unitarity is neglected. This provides an object lesson in how unitarity teaches us to add resonances. Not surprisingly the result is crucially dependent on the pole position of the f 0(980), for which there are still sizeable uncertainties. At present this leads to an uncertainty in the φto γ f_0 branching ratio which can only be fixed by further precision data on the f 0(980). Nevertheless, the {BR}(φ to γ f_0) is now the same order of magnitude as the experimental {BR}(φ to γ a_0).

  14. Multiple effects of consonant manner of articulation and intonation type on F0 in English

    NASA Astrophysics Data System (ADS)

    Xu, Yi; Wallace, Andrew

    2004-05-01

    In this study we examine how consonant manner of articulation interacts with intonation type in shaping the F0 contours in English. Native speakers of American English read aloud words differing in vowel length, consonant manner of articulation and consonant position in word. They produced each word in either a statement or question carrier. F0 contours of their speech were extracted by measuring every complete vocal period. Preliminary results based on graphic analysis of three speakers' data suggest that there are three distinct consonantal effects: F0 interruption due to devoicing, a large but brief (10-40 ms) F0 raising at the onset of voicing, and a smaller but longer-lasting F0 raising throughout a large proportion of the preceding and following vowels. These effects appear to be imposed on a continuously changing F0 curve that is either rising-falling or falling-rising, depending on whether the carrier sentence is a statement or a question. Further analysis will test the hypothesis that these continuous curves result from local pitch targets that are assigned to individual syllables and implemented with them in synchrony regardless of their segmental composition. [Work supported by NIDCD Grant No. R01 DC03902.

  15. Effects of age on F0 discrimination and intonation perception in simulated electric and electroacoustic hearing.

    PubMed

    Souza, Pamela; Arehart, Kathryn; Miller, Christi Wise; Muralimanohar, Ramesh Kumar

    2011-02-01

    Recent research suggests that older listeners may have difficulty processing information related to the fundamental frequency (F0) of voiced speech. In this study, the focus was on the mechanisms that may underlie this reduced ability. We examined whether increased age resulted in decreased ability to perceive F0 using fine-structure cues provided by the harmonic structure of voiced speech sounds or cues provided by high-rate envelope fluctuations (periodicity). Younger listeners with normal hearing and older listeners with normal to near-normal hearing completed two tasks of F0 perception. In the first task (steady state F0), the fundamental frequency difference limen (F0DL) was measured adaptively for synthetic vowel stimuli. In the second task (time-varying F0), listeners relied on variations in F0 to judge intonation of synthetic diphthongs. For both tasks, three processing conditions were created: eight-channel vocoding that preserved periodicity cues to F0; a simulated electroacoustic stimulation condition, which consisted of high-frequency vocoder processing combined with a low-pass-filtered portion, and offered both periodicity and fine-structure cues to F0; and an unprocessed condition. F0 difference limens for steady state vowel sounds and the ability to discern rising and falling intonations were significantly worse in the older subjects compared with the younger subjects. For both older and younger listeners, scores were lowest for the vocoded condition, and there was no difference in scores between the unprocessed and electroacoustic simulation conditions. Older listeners had difficulty using periodicity cues to obtain information related to talker fundamental frequency. However, performance was improved by combining periodicity cues with (low frequency) acoustic information, and that strategy should be considered in individuals who are appropriate candidates for such processing. For cochlear implant candidates, this effect might be achieved by partial

  16. Anisotropy in SmFeAsO0.8F0.15 single crystal

    NASA Astrophysics Data System (ADS)

    Pattanaik, A.; Nayak, P.

    2013-06-01

    The high temperature superconductors in the mixed state rounding superconducting transition temperature have been explained by using anisotropic London theory as well as GL-equation. Due to strong overlapping of vortices at higher fields the super electron density varies in space and London theory fails to explain. For lower critical field with in London limit and temperature close to transition, GL-approach with phenomenological mass tensor can be approximated for studying mixed state behavior. Expressing bare penetration depth λ into effective penetration depth λeff such as λeff2=λ2/f2 = λ2/1-b;f = 1-b and b = ba/Bc2, the high field behavior can be observed using 3D-anisotropic London theory by incorporating vortex overlapping. FeAs superconductors have distinguishing macroscopic properties such as an enormous upper critical field with low superconducting anisotropy and that leads the investigation of topology in the microscopic length scale. Particularly, the variation of specific heat as well as entropy in SmFeAsO0.8F0.15 has been verified by the GL-theory in London limit with vortex overlapping correction and found satisfactory result with the experimental findings.

  17. Vocalization-induced enhancement of the auditory cortex responsiveness during voice F0 feedback perturbation.

    PubMed

    Behroozmand, Roozbeh; Karvelis, Laura; Liu, Hanjun; Larson, Charles R

    2009-07-01

    The present study investigated whether self-vocalization enhances auditory neural responsiveness to voice pitch feedback perturbation and how this vocalization-induced neural modulation can be affected by the extent of the feedback deviation. Event-related potentials (ERPs) were recorded in 15 subjects in response to +100, +200 and +500 cents pitch-shifted voice auditory feedback during active vocalization and passive listening to the playback of the self-produced vocalizations. The amplitude of the evoked P(1) (latency: 73.51 ms) and P(2) (latency: 199.55 ms) ERP components in response to feedback perturbation were significantly larger during vocalization than listening. The difference between P(2) peak amplitudes during vocalization vs. listening was shown to be significantly larger for +100 than +500 cents stimulus. Results indicate that the human auditory cortex is more responsive to voice F(0) feedback perturbations during vocalization than passive listening. Greater vocalization-induced enhancement of the auditory responsiveness to smaller feedback perturbations may imply that the audio-vocal system detects and corrects for errors in vocal production that closely match the expected vocal output. Findings of this study support previous suggestions regarding the enhanced auditory sensitivity to feedback alterations during self-vocalization, which may serve the purpose of feedback-based monitoring of one's voice.

  18. Influence of F0 and Sequence Length of Audio and Electroglottographic Signals on Perturbation Measures for Voice Assessment.

    PubMed

    Hohm, Julian; Döllinger, Michael; Bohr, Christopher; Kniesburges, Stefan; Ziethe, Anke

    2015-07-01

    Within the functional assessment of voice disorders, an objective analysis of measured parameters from audio, electroglottographic (EGG), or visual signals is desired. In a typical clinical situation, reliable objective analysis is not always possible due to missing standardization and unknown stability of the clinical parameters. The aim of this study was to investigate the robustness/stability of measured clinical parameters of the audio and EGG signals in a typical clinical setting to ensure a reliable objective analysis. In particular, the influence of F0 and of the sequence length on several definitions of jitter and shimmer will be analyzed. Seventy-four young healthy women produced a sustained vowel /a/ and an upward triad with abrupt changeovers. Different sequence lengths (100, 150, 500, and 1000 ms) of sustained phonation and triads (100 and 150 ms) were extracted from the audio and EGG signals. In total, six variations of jitter and four variations of shimmer parameters were analyzed. Jitter%, Jitter11p, and JitterPPQ of the audio signal as well as Jittermean, Shimmer, and Shimmer11p of the EGG signal are unaffected by both sequence length and F0. Influence of F0 and sequence length on several perturbation measures of the audio and EGG signals was identified. For an objective clinical voice assessment, unaffected definitions of jitter and shimmer should be preferred and applied to enable comparability between different recordings, examinations, and studies. Copyright © 2015 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  19. Bs → f0(980) Transition Form Factors Within the kT Factorization Approach

    NASA Astrophysics Data System (ADS)

    Zeng, Dai-Min; Fang, Zhen-Yun

    2013-04-01

    In the paper, we apply the kT factorization approach to deal with the Bs → f0 (980) transition form factors in the large recoil regions, i.e. the small q2 regions. For the purpose, we adopt the B-meson wave-functions ΦB, and δ that include the three-Fock states contributions to do our discussion. Although the scalar meson f0(980) is widely perceived as the 4-quark bound state (scenario 2), but the distribution amplitudes of 4-quark states are still unknown to us, so we adopt 2-quark model (scenario 1) for scalar meson f0(980) in our discussion. By varying the B-meson wave-function parameters within their reasonable regions, we obtain F0(0) = F+(0) = 0.20 ± 0.02, FT(0) = 0.24 ± 0.02. Our present results for these form factors are consistent with the light-cone sum rule results obtained in the literature.

  20. Processing F0 with Cochlear Implants: Modulation Frequency Discrimination and Speech Intonation Recognition

    PubMed Central

    Chatterjee, Monita; Peng, Shu-Chen

    2008-01-01

    Fundamental frequency (F0) processing by cochlear implant (CI) listeners was measured using a psychophysical task and a speech intonation recognition task. Listeners’ Weber fractions for modulation frequency discrimination were measured using an adaptive, 3-interval, forced-choice paradigm: stimuli were presented through a custom research interface. In the speech intonation recognition task, listeners were asked to indicate whether resynthesized bisyllabic words, when presented in the free field through the listeners’ everyday speech processor, were question-like or statement-like. The resynthesized tokens were systematically manipulated to have different initial F0s to represent male vs. female voices, and different F0 contours (i.e., falling, flat, and rising) Although the CI listeners showed considerable variation in performance on both tasks, significant correlations were observed between the CI listeners’ sensitivity to modulation frequency in the psychophysical task and their performance in intonation recognition. Consistent with their greater reliance on temporal cues, the CI listeners’ performance in the intonation recognition task was significantly poorer with the higher initial-F0 stimuli than with the lower initial-F0 stimuli. Similar results were obtained with normal hearing listeners attending to noiseband-vocoded CI simulations with reduced spectral resolution. PMID:18093766

  1. Investigation of some transitions and lifetimes in Xe ii

    NASA Astrophysics Data System (ADS)

    Broström, L.; Mannervik, S.; Passian, A.; Sundström, G.

    1994-05-01

    The lifetimes of the 6p 2 Do5/2, 6p 4Po5/2, 6p 4 Do7/2, 6p 4Do5/2, and 6p 2Fo7/2 levels in Xe ii have been measured with a beam-laser technique. A detailed spectroscopic investigation of the fluorescence channels of the excited states has been performed to confirm the identifications. As a consequence of some reassignments experimental lifetime values can now unambiguously be ascribed to these levels.

  2. Measurement of branching ratio and B0s lifetime in the decay B0s → J/ψ f0(980) at CDF

    DOE PAGES

    Aaltonen, T.

    2011-09-30

    We present a study of Bs0 decays to the CP-odd final state J/ψ f0(980) with J/ψ → µ+µ- and f0(980) → π+π-. Using pp̄ collision data with an integrated luminosity of 3.8 fb-1 collected by the CDF II detector at the Tevatron we measure a Bs0 lifetime of τ(B0s → J/ψ f0(980)) = 1.70-0.11+0.12(stat) ± 0.03(syst) ps. This is the first measurement of the Bs0} lifetime in a decay to a CP eigenstate and corresponds in the standard model to the lifetime of the heavy Bs0 eigenstate. We also measure the product of branching fractions of B0s → J/ψ f0(980)more » and f0(980) → π+π- relative to the product of branching fractions of B0s → J/ψφ and φ→K+K- to be Rf0/ψ = 0.257 ± 0.020(stat) ± 0.014(syst), which is the most precise determination of this quantity to date.« less

  3. Contrast harmonic detection with chirp excitation in 3f0 transmit phasing.

    PubMed

    Shen, Che-Chou; Wang, Hong-Wei; Chiu, Yi-Yuan

    2008-10-01

    The method of third harmonic (3f0 transmit phasing is capable of providing effective tissue background suppression for contrast-to-tissue ratio (CTR) improvement in harmonic imaging. With the additional 3f0 transmit signal to generate both the frequency-sum and the frequency-difference components of harmonic signal, the tissue suppression is achieved when the two components are opposite in phase and mutually cancel out. One major problem in 3f0 transmit phasing is the limited signal-to-noise ratio (SNR) due to the constraint on transmit amplitude. Chirp excitation can be applied in contrast harmonic imaging to enhance the SNR with minimal destruction of the microbubbles. In this paper, the effect of chirp waveform in combination with the 3f0 transmit phasing was studied using both in-vitro experiments and simulations. Our results indicate that, though the chirp transmit pulse can increase the SNR of harmonic imaging in 3f0 transmit phasing (3 dB, p < 0.001), it suffers from degraded tissue harmonic suppression and thus provides less CTR improvement as compared to a conventional pulse. The spectral mismatch between the frequency-sum and the frequency-difference components of tissue harmonic signal is particularly evident in the off-center region of second harmonic band, leading to significant residue tissue background. Consequently, with the chirp waveform, the improvement of CTR decreases from 9.5 dB to 5.9 dB (p < 0.0006) and thus a tradeoff exists between the SNR improvement and the CTR improvement in 3f0 transmit phasing.

  4. First Observation of η(1405) Decays into f0(980)π0

    NASA Astrophysics Data System (ADS)

    Ablikim, M.; Achasov, M. N.; Alberto, D.; Ambrose, D. J.; An, F. F.; An, Q.; An, Z. H.; Bai, J. Z.; Baldini Ferroli, R. B. F.; Ban, Y.; Becker, J.; Berger, N.; Bertani, M. B.; Bian, J. M.; Boger, E.; Bondarenko, O.; Boyko, I.; Briere, R. A.; Bytev, V.; Cai, X.; Calcaterra, A. C.; Cao, G. F.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, J. C.; Chen, M. L.; Chen, S. J.; Chen, Y.; Chen, Y. B.; Cheng, H. P.; Chu, Y. P.; Cronin-Hennessy, D.; Dai, H. L.; Dai, J. P.; Dedovich, D.; Deng, Z. Y.; Denysenko, I.; Destefanis, M.; Ding Ding, W. L.; Ding, Y.; Dong, L. Y.; Dong, M. Y.; Du, S. X.; Fang, J.; Fang, S. S.; Feng, C. Q.; Fu, C. D.; Fu, J. L.; Gao, Y.; Geng, C.; Goetzen, K.; Gong, W. X.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, Y. P.; Han, Y. L.; Hao, X. Q.; Harris, F. A.; He, K. L.; He, M.; He, Z. Y.; Heng, Y. K.; Hou, Z. L.; Hu, H. M.; Hu, J. F.; Hu, T.; Huang, B.; Huang, G. M.; Huang, J. S.; Huang, X. T.; Huang, Y. P.; Hussain, T.; Ji, C. S.; Ji, Q.; Ji, X. B.; Ji, X. L.; Jia, L. K.; Jiang, L. L.; Jiang, X. S.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Jing, F. F.; Kalantar-Nayestanaki, N.; Kavatsyuk, M.; Kuehn, W.; Lai, W.; Lange, J. S.; Leung, J. K. C.; Li, C. H.; Li, Cheng; Li, Cui; Li, D. M.; Li, F.; Li, G.; Li, H. B.; Li, J. C.; Li, K.; Li, Lei; Li, N. B.; Li, Q. J.; Li, S. L.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, X. R.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Liao, X. T.; Liu, B. J.; Liu, C. L.; Liu, C. X.; Liu, C. Y.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H.; Liu, H. B.; Liu, H. H.; Liu, H. M.; Liu, H. W.; Liu, J. P.; Liu, K.; Liu, K.; Liu, K. Y.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, X. H.; Liu, Y. B.; Liu, Yong; Liu, Z. A.; Liu, Zhiqiang; Liu, Zhiqing; Loehner, H.; Lu, G. R.; Lu, H. J.; Lu, J. G.; Lu, Q. W.; Lu, X. R.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lv, M.; Ma, C. L.; Ma, F. C.; Ma, H. L.; Ma, Q. M.; Ma, S.; Ma, T.; Ma, X. Y.; Maggiora, M.; Malik, Q. A.; Mao, H.; Mao, Y. J.; Mao, Z. P.; Messchendorp, J. G.; Min, J.; Min, T. J.; Mitchell, R. E.; Mo, X. H.; Muchnoi, N. Yu.; Nefedov, Y.; Nikolaev, I. B.; Ning, Z.; Olsen, S. L.; Ouyang, Q.; Pacetti, S. P.; Park, J. W.; Pelizaeus, M.; Peters, K.; Ping, J. L.; Ping, R. G.; Poling, R.; Pun, C. S. J.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, X. S.; Qiu, J. F.; Rashid, K. H.; Rong, G.; Ruan, X. D.; Sarantsev, A.; Schulze, J.; Shao, M.; Shen, C. P.; Shen, X. Y.; Sheng, H. Y.; Shepherd, M. R.; Song, X. Y.; Spataro, S.; Spruck, B.; Sun, D. H.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. D.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Thorndike, E. H.; Tian, H. L.; Toth, D.; Varner, G. S.; Wan, X.; Wang, B.; Wang, B. Q.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, Q.; Wang, Q. J.; Wang, S. G.; Wang, X. F.; Wang, X. L.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. Y.; Wei, D. H.; Wen, Q. G.; Wen, S. P.; Wiedner, U.; Wu, L. H.; Wu, N.; Wu, W.; Wu, Z.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, G. M.; Xu, H.; Xu, Q. J.; Xu, X. P.; Xu, Y.; Xu, Z. R.; Xue, Z.; Yan, L.; Yan, W. B.; Yan, Y. H.; Yang, H. X.; Yang, T.; Yang, Y.; Yang, Y. X.; Ye, H.; Ye, M.; Ye, M. H.; Yu, B. X.; Yu, C. X.; Yu, S. P.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Zafar, A. A.; Zallo, A. Z.; Zeng, Y.; Zhang, B. X.; Zhang, B. Y.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, L.; Zhang, S. H.; Zhang, T. R.; Zhang, X. J.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. S.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, H. S.; Zhao, Jingwei; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, S. J.; Zhao, T. C.; Zhao, X. H.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, Y. H.; Zheng, Z. P.; Zhong, B.; Zhong, J.; Zhou, L.; Zhou, X. K.; Zhou, X. R.; Zhu, C.; Zhu, K.; Zhu, K. J.; Zhu, S. H.; Zhu, X. L.; Zhu, X. W.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zou, B. S.; Zou, J. H.; Zuo, J. X.

    2012-05-01

    The decays J/ψ→γπ+π-π0 and J/ψ→γπ0π0π0 are analyzed using a sample of 225×106 J/ψ events collected with the BESIII detector. The decay of η(1405)→f0(980)π0 with a large isospin violation is observed for the first time. The width of the f0(980) observed in the dipion mass spectra is anomalously narrower than the world average. Decay rates for three-pion decays of the η' are also measured precisely.

  5. The Framework for 0-D Atmospheric Modeling (F0AM) v3.1

    NASA Technical Reports Server (NTRS)

    Wolfe, Glenn M.; Marvin, Margaret R.; Roberts, Sandra J.; Travis, Katherine R.; Liao, Jin

    2016-01-01

    The Framework for 0-D Atmospheric Modeling(F0AM) is a flexible and user-friendly MATLAB-based platform for simulation of atmospheric chemistry systems. The F0AM interface incorporates front-end configuration of observational constraints and model setups, making it readily adaptable to simulation of photochemical chambers, Lagrangian plumes, and steady-state or time-evolving solar cycles. Six different chemical mechanisms and three options for calculation of photolysis frequencies are currently available. Example simulations are presented to illustrate model capabilities and, more generally, highlight some of the advantages and challenges of 0-D box modeling.

  6. First measurement of direct $f_0(980)$ photoproduction on the proton

    SciTech Connect

    Battaglieri, Marco; De Vita, Raffaella; Szczepaniak, Adam

    2009-03-01

    We report on the results of the first measurement of exclusive $f_0(980)$ meson photoproduction on protons for $E_\\gamma=3.0 - 3.8$ GeV and $-t = 0.4-1.0$ GeV$^2$. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the $\\pi^+ \\pi^-$ channel by performing a partial wave analysis of the reaction $\\gamma p \\to p \\pi^+ \\pi^-$. Clear evidence of the $f_0(980)$ meson was found in the interference between $P$ and $S$ waves at $M_{\\pi^+ \\pi^-}\\sim 1$ GeV. The $S$-wave differential cross section integrated in the mass range of the $f_0(980)$ was found to be a factor of 50 smaller than the cross section for the $\\rho$ meson. This is the first time the $f_0(980)$ meson has been measured in a photoproduction experiment.

  7. The Scalar Resonances a0/f0(980) at COSY

    SciTech Connect

    Buescher, M.

    2006-02-11

    Fundamental properties of the scalar resonances a0/f0(980), like their masses, widths and couplings to KK-bar, are poorly known. In particular, precise knowledge of the latter quantity would be of great importance since it can be related to the KK-bar content of these resonances.An experimental program is under way at COSY-Juelich aiming at the extraction of the isospin violating a0/f0 mixing amplitude {lambda} which is in leading order proportional to the product of the coupling constants of the a0 and f0 to kaons. a0/f0 production is studied in pp, pn and dd interactions, both for the KK-bar and the {pi}{eta}/{pi}{pi} decays, using the ANKE and WASA spectrometers. The latter will be available for measurements at COSY in 2007.As a first step, isovector KK-bar production has been measured in the reaction pp {yields} dK+K-bar0. The data reveal dominance of the a{sub 0}{sup +} channel, thus demonstrating the feasibility of scalar meson studies at COSY. Analyses of KK-bar- and K-bard-FSI effects yield the corresponding scattering lengths, a(KK-bar)I=1 = -(0.02 {+-} 0.03) - i(0.61 {+-} 0.05) fm and vertical bar Re a(K-bard) vertical bar {<=}1.3 fm, Im a(K-bard){<=}1.3 fm.

  8. 3D Structure of Brownmillerite Ba1.95In2O4.9F0.1

    NASA Astrophysics Data System (ADS)

    Tarasova, N.; Animitsa, I.; Galisheva, A.

    2017-09-01

    In this paper, the questions about location of fluorine atoms in the structure and the changes in the lengths of indium-oxygen bonds were resolved. The crystal structure of fluorine doped brownmillerite Ba1.95In2O4.9F0.1 was investigated. It was found that fluorine atoms are localized in tetrahedra [InO3F]. The change in the length of In-O bonds at fluorine substitution is determined. The change in the bonds lengths leads to a change in the mobility of the carrier, and, accordingly, to a change of the ionic conductivity.

  9. Gas Atomization of Amorphous Aluminum Powder: Part II. Experimental Investigation

    NASA Astrophysics Data System (ADS)

    Zheng, Baolong; Lin, Yaojun; Zhou, Yizhang; Lavernia, Enrique J.

    2009-12-01

    The optimal processing parameters that are required to atomize amorphous Al were established on the basis of numerical simulations in part I of this study. In this part II, the characterization of cooling rate experienced by gas-atomized, Al-based amorphous powders was studied via experiments. An experimental investigation was implemented to validate the numerical predictions reported in part I of this study. The cooling rate experienced by the powders, for example, was experimentally determined on the basis of dendrite arm spacing correlations, and the results were compared with the numerical predictions. The experimental studies were completed using commercial Al 2024 as a baseline material and Al90Gd7Ni2Fe1 metallic glass (MG). The results showed that the cooling rate of droplets increases with decreasing particle size, with an increasing proportion of helium in the atomization gas and with increasing melt superheat. The experimental results reported in this article suggest good agreement between experiments and numerical simulations.

  10. Generation of fertile and fecund F0 XY female mice from XY ES cells.

    PubMed

    Kuno, Junko; Poueymirou, William T; Gong, Guochun; Siao, Chia-Jen; Clarke, Georgia; Esau, Lakeisha; Kojak, Nada; Posca, Julita; Atanasio, Amanda; Strein, John; Yancopoulos, George D; Lai, Ka-Man Venus; DeChiara, Thomas M; Frendewey, David; Auerbach, Wojtek; Valenzuela, David M

    2015-02-01

    Known examples of male to female sex reversal in mice are caused by either strain incompatibilities or mutations in genes required for male sex determination. The resultant XY females are often sterile or exhibit very poor fertility. We describe here embryonic stem (ES) cell growth conditions that promote the production of healthy, anatomically normal fertile and fecund female F0 generation mice completely derived from gene-targeted XY male ES cells. The sex reversal is a transient trait that is not transmitted to the F1 progeny. Growth media with low osmolality and reduced sodium bicarbonate, maintained throughout the gene targeting process, enhance the yield of XY females. As a practical application of the induced sex reversal, we demonstrate the generation of homozygous mutant mice ready for phenotypic studies by the breeding of F0 XY females with their isogenic XY male clonal siblings, thereby eliminating one generation of breeding and the associated costs.

  11. Non-ordinary nature of the f_0(500) resonance from its Regge trajectory

    SciTech Connect

    Nebreda, J.; Londergan, J. Timothy; Pelaez, J. R.; Szczepaniak, Adam P.

    2014-07-01

    We report our results on how to obtain the Regge trajectory of a resonance from its pole in a scattering process by imposing analytic constraints in the complex angular momentum plane. The method, suited for resonances that dominate an elastic scattering amplitude, has been applied to the {\\rho}(770) and the f_0(500) resonances. Whereas for the former we obtain a linear Regge trajectory, characteristic of ordinary quark-antiquark states, for the latter we find a non-linear trajectory with a much smaller slope at the resonance mass. Moreover, we show that if a linear trajectory with a slope of typical size is imposed for the f_0(500), the corresponding amplitude is at odds with the data. This provides a strong indication of the non-ordinary nature of the sigma meson.

  12. Cloning, sequence analysis and expression of the F1F0-ATPase beta-subunit from wine lactic acid bacteria.

    PubMed

    Sievers, Martin; Uermösi, Christina; Fehlmann, Marc; Krieger, Sibylle

    2003-09-01

    The nucleotide sequences of the genes encoding the F1F0-ATPase beta-subunit from Oenococcus oeni, Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus damnosus, Pediococcus parvulus, Lactobacillus brevis and Lactobacillus hilgardii were determined. Their deduced amino acid sequences showed homology values of 79-98%. Data from the alignment and ATPase tree indicated that O. oeni and L. mesenteroides subsp. mesenteroides formed a group well-separated from P. damnosus and P. parvulus and from the group comprises L. brevis and L. hilgardii. The N-terminus of the F1F0-ATPase beta-subunit of O. oeni contains a stretch of additional 38 amino acid residues. The catalytic site of the ATPase beta-subunit of the investigated strains is characterized by the two conserved motifs GGAGVGKT and GERTRE. The amplified atpD coding sequences were inserted into the pCRT7/CT-TOPO vector using TA-cloning strategy and transformed in Escherichia coli. SDS-PAGE and Western blot analyses confirmed that O. oeni has an ATPase beta-subunit protein which is larger in size than the corresponding molecules from the investigated strains.

  13. Functional asymmetry of the F(0) motor in bacterial ATP synthases.

    PubMed

    Wiedenmann, Alexander; Dimroth, Peter; von Ballmoos, Christoph

    2009-04-01

    F(1)F(0) ATP synthases use the electrochemical potential of H(+) or Na(+) across biological membranes to synthesize ATP by a rotary mechanism. In bacteria, the enzymes can act in reverse as ATP-driven ion pumps creating the indispensable membrane potential. Here, we demonstrate that the F(0) parts of a Na(+)- and H(+)-dependent enzyme display major asymmetries with respect to their mode of operation, reflected by the requirement of approximately 100 times higher Na(+) or H(+) concentrations for the synthesis compared with the hydrolysis of ATP. A similar asymmetry is observed during ion transport through isolated F(0) parts, indicating different affinities for the binding sites in the a/c interface. Together with further data, we propose a model that provides a rationale for a differential usage of membrane potential and ion gradient during ATP synthesis as observed experimentally. The functional asymmetry might also reflect an important property of the ATP synthesis mechanism in vivo. In Escherichia coli, we observed respiratory chain-driven ATP production at pH 7-8, while P-site pH values < 6.5 were required for ATP synthesis in vitro. This discrepancy is discussed with respect to the hypothesis that during respiration lateral proton diffusion could lead to significant acidification at the membrane surface.

  14. Simultaneous F 0-F 1 modifications of Arabic for the improvement of natural-sounding

    NASA Astrophysics Data System (ADS)

    Ykhlef, F.; Bensebti, M.

    2013-03-01

    Pitch (F 0) modification is one of the most important problems in the area of speech synthesis. Several techniques have been developed in the literature to achieve this goal. The main restrictions of these techniques are in the modification range and the synthesised speech quality, intelligibility and naturalness. The control of formants in a spoken language can significantly improve the naturalness of the synthesised speech. This improvement is mainly dependent on the control of the first formant (F 1). Inspired by this observation, this article proposes a new approach that modifies both F 0 and F 1 of Arabic voiced sounds in order to improve the naturalness of the pitch shifted speech. The developed strategy takes a parallel processing approach, in which the analysis segments are decomposed into sub-bands in the wavelet domain, modified in the desired sub-band by using a resampling technique and reconstructed without affecting the remained sub-bands. Pitch marking and voicing detection are performed in the frequency decomposition step based on the comparison of the multi-level approximation and detail signals. The performance of the proposed technique is evaluated by listening tests and compared to the pitch synchronous overlap and add (PSOLA) technique in the third approximation level. Experimental results have shown that the manipulation in the wavelet domain of F 0 in conjunction with F 1 guarantees natural-sounding of the synthesised speech compared to the classical pitch modification technique. This improvement was appropriate for high pitch modifications.

  15. Sociological effects on vocal aging: Age related F0 effects in two languages

    NASA Astrophysics Data System (ADS)

    Nagao, Kyoko

    2005-04-01

    Listeners can estimate the age of a speaker fairly accurately from their speech (Ptacek and Sander, 1966). It is generally considered that this perception is based on physiologically determined aspects of the speech. However, the degree to which it is due to conventional sociolinguistic aspects of speech is unknown. The current study examines the degree to which fundamental frequency (F0) changes due to advanced aging across two language groups of speakers. It also examines the degree to which the speakers associate these changes with aging in a voice disguising task. Thirty native speakers each of English and Japanese, taken from three age groups, read a target phrase embedded in a carrier sentence in their native language. Each speaker also read the sentence pretending to be 20-years younger or 20-years older than their own age. Preliminary analysis of eighteen Japanese speakers indicates that the mean and maximum F0 values increase when the speakers pretended to be younger than when they pretended to be older. Some previous studies on age perception, however, suggested that F0 has minor effects on listeners' age estimation. The acoustic results will also be discussed in conjunction with the results of the listeners' age estimation of the speakers.

  16. Robust F0 Estimation Using ELS-Based Robust Complex Speech Analysis

    NASA Astrophysics Data System (ADS)

    Funaki, Keiichi; Kinjo, Tatsuhiko

    Complex speech analysis for an analytic speech signal can accurately estimate the spectrum in low frequencies since the analytic signal provides spectrum only over positive frequencies. The remarkable feature makes it possible to realize more accurate F0 estimation using complex residual signal extracted by complex-valued speech analysis. We have already proposed F0 estimation using complex LPC residual, in which the autocorrelation function weighted by AMDF was adopted as the criterion. The method adopted MMSE-based complex LPC analysis and it has been reported that it can estimate more accurate F0 for IRS filtered speech corrupted by white Gauss noise although it can not work better for the IRS filtered speech corrupted by pink noise. In this paper, robust complex speech analysis based on ELS (Extended Least Square) method is introduced in order to overcome the drawback. The experimental results for additive white Gauss or pink noise demonstrate that the proposed algorithm based on robust ELS-based complex AR analysis can perform better than other methods.

  17. Logarithmic temporal axis manipulation and its application for measuring auditory contributions in F0 control using a transformed auditory feedback procedure

    NASA Astrophysics Data System (ADS)

    Yanaga, Ryuichiro; Kawahara, Hideki

    2003-10-01

    A new parameter extraction procedure based on logarithmic transformation of the temporal axis was applied to investigate auditory effects on voice F0 control to overcome artifacts due to natural fluctuations and nonlinearities in speech production mechanisms. The proposed method may add complementary information to recent findings reported by using frequency shift feedback method [Burnett and Larson, J. Acoust. Soc. Am. 112 (2002)], in terms of dynamic aspects of F0 control. In a series of experiments, dependencies of system parameters in F0 control on subjects, F0 and style (musical expressions and speaking) were tested using six participants. They were three male and three female students specialized in musical education. They were asked to sustain a Japanese vowel /a/ for about 10 s repeatedly up to 2 min in total while hearing F0 modulated feedback speech, that was modulated using an M-sequence. The results replicated qualitatively the previous finding [Kawahara and Williams, Vocal Fold Physiology, (1995)] and provided more accurate estimates. Relations with designing an artificial singer also will be discussed. [Work partly supported by the grant in aids in scientific research (B) 14380165 and Wakayama University.

  18. Measurements of branching fractions, polarizations, and direct CP-violation asymmetries in B-->rhoK* and B-->f0(980)K* decays.

    PubMed

    Aubert, B; Barate, R; Bona, M; Boutigny, D; Couderc, F; Karyotakis, Y; Lees, J P; Poireau, V; Tisserand, V; Zghiche, A; Grauges, E; Palano, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Battaglia, M; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Gill, M S; Groysman, Y; Jacobsen, R G; Kadyk, J A; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Wenzel, W A; del Amo Sanchez, P; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Peters, K; Schroeder, T; Steinke, M; Boyd, J T; Burke, J P; Cottingham, W N; Walker, D; Cuhadar-Donszelmann, T; Fulsom, B G; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Khan, A; Kyberd, P; Saleem, M; Sherwood, D J; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Best, D S; Bondioli, M; Bruinsma, M; Chao, M; Curry, S; Eschrich, I; Kirkby, D; Lankford, A J; Lund, P; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Abachi, S; Buchanan, C; Foulkes, S D; Gary, J W; Long, O; Shen, B C; Wang, K; Zhang, L; Hadavand, H K; Hill, E J; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Cunha, A; Dahmes, B; Hong, T M; Kovalskyi, D; Richman, J D; Beck, T W; Eisner, A M; Flacco, C J; Heusch, C A; Kroseberg, J; Lockman, W S; Nesom, G; Schalk, T; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dvoretskii, A; Fang, F; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Mancinelli, G; Meadows, B T; Mishra, K; Sokoloff, M D; Blanc, F; Bloom, P C; Chen, S; Ford, W T; Hirschauer, J F; Kreisel, A; Nagel, M; Nauenberg, U; Olivas, A; Ruddick, W O; Smith, J G; Ulmer, K A; Wagner, S R; Zhang, J; Chen, A; Eckhart, E A; Soffer, A; Toki, W H; Wilson, R J; Winklmeier, F; Zeng, Q; Altenburg, D D; Feltresi, E; Hauke, A; Jasper, H; Petzold, A; Spaan, B; Brandt, T; Klose, V; Lacker, H M; Mader, W F; Nogowski, R; Schubert, J; Schubert, K R; Schwierz, R; Sundermann, J E; Volk, A; Bernard, D; Bonneaud, G R; Grenier, P; Latour, E; Thiebaux, Ch; Verderi, M; Clark, P J; Gradl, W; Muheim, F; Playfer, S; Robertson, A I; Xie, Y; Andreotti, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Petrella, A; Piemontese, L; Prencipe, E; Anulli, F; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Pacetti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Rama, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Lo Vetere, M; Macri, M M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Brandenburg, G; Chaisanguanthum, K S; Morii, M; Wu, J; Dubitzky, R S; Marks, J; Schenk, S; Uwer, U; Bard, D J; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Flack, R L; Nash, J A; Nikolich, M B; Panduro Vazquez, W; Behera, P K; Chai, X; Charles, M J; Mallik, U; Meyer, N T; Ziegler, V; Cochran, J; Crawley, H B; Dong, L; Eyges, V; Meyer, W T; Prell, S; Rosenberg, E I; Rubin, A E; Gritsan, A V; Denig, A G; Fritsch, M; Schott, G; Arnaud, N; Davier, M; Grosdidier, G; Höcker, A; Le Diberder, F; Lepeltier, V; Lutz, A M; Oyanguren, A; Pruvot, S; Rodier, S; Roudeau, P; Schune, M H; Stocchi, A; Wang, W F; Wormser, G; Cheng, C H; Lange, D J; Wright, D M; Chavez, C A; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; George, K A; Hutchcroft, D E; Payne, D J; Schofield, K C; Touramanis, C; Bevan, A J; Di Lodovico, F; Menges, W; Sacco, R; Cowan, G; Flaecher, H U; Hopkins, D A; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Wren, A C; Brown, D N; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Chia, Y M; Edgar, C L; Lafferty, G D; Naisbit, M T; Williams, J C; Yi, J I; Chen, C; Hulsbergen, W D; Jawahery, A; Lae, C K; Roberts, D A; Simi, G; Blaylock, G; Dallapiccola, C; Hertzbach, S S; Li, X; Moore, T B; Saremi, S; Staengle, H; Cowan, R; Sciolla, G; Sekula, S J; Spitznagel, M; Taylor, F; Yamamoto, R K; Kim, H; McLachlin, S E; Patel, P M; Robertson, S H; Lazzaro, A; Lombardo, V; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Simard, M; Taras, P; Viaud, F B; Nicholson, H; Cavallo, N; De Nardo, G; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Raven, G; Snoek, H L; Jessop, C P; LoSecco, J M; Allmendinger, T; Benelli, G; Gan, K K; Honscheid, K; Hufnagel, D; Jackson, P D; Kagan, H; Kass, R; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Blount, N L; Brau, J; Frey, R; Igonkina, O; Lu, M; Rahmat, R; Sinev, N B; Strom, D; Strube, J; Torrence, E; Gaz, A; Margoni, M; Morandin, M; Pompili, A; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Voci, C; Benayoun, M; Chauveau, J; Briand, H; David, P; Del Buono, L; de la Vaissière, Ch; Hamon, O; Hartfiel, B L; John, M J J; Leruste, Ph; Malclès, J; Ocariz, J; Roos, L; Therin, G; Gladney, L; Panetta, J; Biasini, M; Covarelli, R; Angelini, C; Batignani, G; Bettarini, S; Bucci, F; Calderini, G; Carpinelli, M; Cenci, R; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Mazur, M A; Morganti, M; Neri, N; Paoloni, E; Rizzo, G; Walsh, J J; Haire, M; Judd, D; Wagoner, D E; Biesiada, J; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; D'Orazio, A; del Re, D; Di Marco, E; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Piredda, G; Polci, F; Safai Tehrani, F; Voena, C; Ebert, M; Schröder, H; Waldi, R; Adye, T; De Groot, N; Franek, B; Olaiya, E O; Wilson, F F; Aleksan, R; Emery, S; Escalier, M; Gaidot, A; Ganzhur, S F; Hamel de Monchenault, G; Kozanecki, W; Legendre, M; Vasseur, G; Yèche, Ch; Zito, M; Chen, X R; Liu, H; Park, W; Purohit, M V; Wilson, J R; Allen, M T; Aston, D; Bartoldus, R; Bechtle, P; Berger, N; Claus, R; Coleman, J P; Convery, M R; Cristinziani, M; Dingfelder, J C; Dorfan, J; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W; Field, R C; Glanzman, T; Gowdy, S J; Graham, M T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Leith, D W G S; Li, S; Luitz, S; Luth, V; Lynch, H L; MacFarlane, D B; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Pulliam, T; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Snyder, A; Stelzer, J; Su, D; Sullivan, M K; Suzuki, K; Swain, S K; Thompson, J M; Va'vra, J; van Bakel, N; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Yi, K; Young, C C; Burchat, P R; Edwards, A J; Majewski, S A; Petersen, B A; Roat, C; Wilden, L; Ahmed, S; Alam, M S; Bula, R; Ernst, J A; Jain, V; Pan, B; Saeed, M A; Wappler, F R; Zain, S B; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Ritchie, J L; Satpathy, A; Schilling, C J; Schwitters, R F; Izen, J M; Lou, X C; Ye, S; Bianchi, F; Gallo, F; Gamba, D; Bomben, M; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Lanceri, L; Vitale, L; Azzolini, V; Martinez-Vidal, F; Banerjee, Sw; Bhuyan, B; Brown, C M; Fortin, D; Hamano, K; Kowalewski, R; Nugent, I M; Roney, J M; Sobie, R J; Back, J J; Harrison, P F; Latham, T E; Mohanty, G B; Pappagallo, M; Band, H R; Chen, X; Cheng, B; Dasu, S; Datta, M; Flood, K T; Hollar, J J; Kutter, P E; Li, H; Mellado, B; Mihalyi, A; Pan, Y; Pierini, M; Prepost, R; Wu, S L; Yu, Z; Neal, H

    2006-11-17

    We report searches for B-meson decays to the charmless final states rhoK* and f0(980)K* with a sample of 232x10(6) BB pairs collected with the BABAR detector at the PEP-II e+e- collider. We measure in units of 10(-6) the following branching fractions, where the first error quoted is statistical and the second systematic, or upper limits are given at the 90% confidence level: B(B+-->rho0K*+)<6.1, B(B+-->rho+K*0)=9.6+/-1.7+/-1.5, B(B0-->rho-K*+)<12.0, B(B0-->rho0K*0)=5.6+/-0.9+/-1.3, B(B+-->f0(980)K*+)=5.2+/-1.2+/-0.5, and B(B0-->f0(980)K*0)<4.3. For the significant modes, we also measure the fraction of longitudinal polarization and the charge asymmetry: fL(B+-->rho+K*0)=0.52+/-0.10+/-0.04, fL(B0-->rho0K*0)=0.57+/-0.09+/-0.08, ACP(B+-->rho+K*0)=-0.01+/-0.16+/-0.02, ACP(B0-->rho0K*0)=0.09+/-0.19+/-0.02, and ACP(B+-->f0(980)K*+)=-0.34+/-0.21+/-0.03.

  19. Superconductivity phase diagram of Se-substituted CeO0.5F0.5Bi(S1-xSex)2

    NASA Astrophysics Data System (ADS)

    Mizuguchi, Yoshikazu; Hiroi, Takafumi; Miura, Osuke

    2016-02-01

    We investigated the effects of Se substitution on the lattice constants and superconducting properties of CeO0.5F0.5Bi(S1-xSex)2. With increasing Se concentration, the a lattice constant increased, while the c lattice constant did not show any significant increase between x = 0.1 and x = 0.5. Bulk superconductivity was observed in samples with x = 0.2-0.4, and the superconducting transition temperature was the highest at x = 0.3. The obtained superconductivity phase diagram was compared to those of LaO0.5F0.5Bi(S1-xSex)2 and NdO0.5F0.5Bi(S1-xSex)2.

  20. Phase II drugs under investigation for allergic conjunctivitis.

    PubMed

    Baiula, Monica; Spampinato, Santi

    2014-12-01

    Ocular allergies comprise a spectrum of conditions that are underreported and underdiagnosed, and are frequently associated with rhinoconjunctivitis. Although allergic conjunctivitis is often not a sight-threatening condition, it could have a significant impact on a person's quality of life, morbidity and productivity. A variety of agents are available for the treatment of allergic conjunctivitis, including antihistamines, mast-cell stabilizers, dual action agents, glucocorticoids, calcineurin inhibitors and immunotherapy. The goal of this review is to investigate new therapeutic strategies for the treatment of ocular allergy. Within, the authors analyze the pharmacological management of allergic conjunctivitis and highlight Phase II clinical trial studies. Recent findings about the pathophysiology of allergic conjunctivitis have enabled us to gain a better understanding of the molecular and cellular mechanisms of ocular disease. This, in turn, has led to the identification of novel targets, which, in turn, has led to the development of new therapeutic agents that are currently under evaluation in the first phases of clinical development. The most interesting agents, under development, are the new topical glucocorticoids, leukotriene receptor antagonists, resolvins, interleukin-1 receptor antagonists and integrin antagonists. The authors now await promising results, which can confirm the therapeutic value of these novel emerging drugs for treating allergic conjunctivitis.

  1. Experimental investigations of He II flows at high Reynolds number

    NASA Technical Reports Server (NTRS)

    Van Sciver, Steve W.

    1991-01-01

    Fluid dynamics studies of He II at high Reynolds number (Re(d) greater than 10 exp 6) reveal characteristics which are best interpreted in terms of classical scaling relationships. In particular, the smooth tube friction factor is seen to correlate with the Von Karman-Nikuradse formulation. Also, the performance of a centrifugal pump is unchanged whether being used with He I or He II. These effects are expected to result provided the He II possesses a viscous sublayer and that the drag is determined by laminar flow within this layer. On the other hand, heat transfer in He II is substantially different from that of He I because of the unique internal convection mechanism present in this quantum fluid. These experiments are performed in the University of Wisconsin liquid helium flow facility which has unique capabilities of He II temperature, pressure and flow.

  2. Mandarin-Speaking Children’s Speech Recognition: Developmental Changes in the Influences of Semantic Context and F0 Contours

    PubMed Central

    Zhou, Hong; Li, Yu; Liang, Meng; Guan, Connie Qun; Zhang, Linjun; Shu, Hua; Zhang, Yang

    2017-01-01

    The goal of this developmental speech perception study was to assess whether and how age group modulated the influences of high-level semantic context and low-level fundamental frequency (F0) contours on the recognition of Mandarin speech by elementary and middle-school-aged children in quiet and interference backgrounds. The results revealed different patterns for semantic and F0 information. One the one hand, age group modulated significantly the use of F0 contours, indicating that elementary school children relied more on natural F0 contours than middle school children during Mandarin speech recognition. On the other hand, there was no significant modulation effect of age group on semantic context, indicating that children of both age groups used semantic context to assist speech recognition to a similar extent. Furthermore, the significant modulation effect of age group on the interaction between F0 contours and semantic context revealed that younger children could not make better use of semantic context in recognizing speech with flat F0 contours compared with natural F0 contours, while older children could benefit from semantic context even when natural F0 contours were altered, thus confirming the important role of F0 contours in Mandarin speech recognition by elementary school children. The developmental changes in the effects of high-level semantic and low-level F0 information on speech recognition might reflect the differences in auditory and cognitive resources associated with processing of the two types of information in speech perception. PMID:28701990

  3. Regge trajectory of the f0(500) resonance from a dispersive connection to its pole

    SciTech Connect

    Nebreda, J.; Londergan, J. Timothy; Pelaez, Jose R.; Szczepaniak, Adam P.

    2014-11-01

    We report here our results on how to obtain the Regge trajectory of a resonance from its pole in a scattering process by imposing analytic constraints in the complex angular momentum plane. The method, suited for resonances that dominate an elastic scattering amplitude, has been applied to the ρ (770) and the f0(500) resonances. Whereas for the former we obtain a linear Regge trajectory, characteristic of ordinary quark-antiquark states, for the latter we find a non-linear trajectory with a much smaller slope at the resonance mass. This provides a strong indication of the non-ordinary nature of the sigma meson.

  4. V S30, slope, H 800 and f 0: performance of various site-condition proxies in reducing ground-motion aleatory variability and predicting nonlinear site response

    NASA Astrophysics Data System (ADS)

    Derras, Boumédiène; Bard, Pierre-Yves; Cotton, Fabrice

    2017-09-01

    The aim of this paper is to investigate the ability of various site-condition proxies (SCPs) to reduce ground-motion aleatory variability and evaluate how SCPs capture nonlinearity site effects. The SCPs used here are time-averaged shear-wave velocity in the top 30 m ( V S30), the topographical slope (slope), the fundamental resonance frequency ( f 0) and the depth beyond which V s exceeds 800 m/s ( H 800). We considered first the performance of each SCP taken alone and then the combined performance of the 6 SCP pairs [ V S30- f 0], [ V S30- H 800], [ f 0-slope], [ H 800-slope], [ V S30-slope] and [ f 0- H 800]. This analysis is performed using a neural network approach including a random effect applied on a KiK-net subset for derivation of ground-motion prediction equations setting the relationship between various ground-motion parameters such as peak ground acceleration, peak ground velocity and pseudo-spectral acceleration PSA ( T), and M w, R JB, focal depth and SCPs. While the choice of SCP is found to have almost no impact on the median ground-motion prediction, it does impact the level of aleatory uncertainty. V S30 is found to perform the best of single proxies at short periods ( T < 0.6 s), while f 0 and H 800 perform better at longer periods; considering SCP pairs leads to significant improvements, with particular emphasis on [ V S30- H 800] and [ f 0-slope] pairs. The results also indicate significant nonlinearity on the site terms for soft sites and that the most relevant loading parameter for characterising nonlinear site response is the "stiff" spectral ordinate at the considered period.[Figure not available: see fulltext.

  5. Voice F0 responses to pitch-shifted voice feedback during English speech.

    PubMed

    Chen, Stephanie H; Liu, Hanjun; Xu, Yi; Larson, Charles R

    2007-02-01

    Previous studies have demonstrated that motor control of segmental features of speech rely to some extent on sensory feedback. Control of voice fundamental frequency (F0) has been shown to be modulated by perturbations in voice pitch feedback during various phonatory tasks and in Mandarin speech. The present study was designed to determine if voice Fo is modulated in a task-dependent manner during production of suprasegmental features of English speech. English speakers received pitch-modulated voice feedback (+/-50, 100, and 200 cents, 200 ms duration) during a sustained vowel task and a speech task. Response magnitudes during speech (mean 31.5 cents) were larger than during the vowels (mean 21.6 cents), response magnitudes increased as a function of stimulus magnitude during speech but not vowels, and responses to downward pitch-shift stimuli were larger than those to upward stimuli. Response latencies were shorter in speech (mean 122 ms) compared to vowels (mean 154 ms). These findings support previous research suggesting the audio vocal system is involved in the control of suprasegmental features of English speech by correcting for errors between voice pitch feedback and the desired F0.

  6. Coexistence of ferromagnetism and superconductivity in CeO_{0.3}F_{0.7}BiS_{2}

    SciTech Connect

    Lee, Jooseop; Demura, S; Stone, Matthew B; Iida, Kazuki; Ehlers, Georg; Dela Cruz, Clarina R; Matsuda, Masaaki; Deguchi, K; Mizuguchi, Y; Miura, O; Louca, Despina; Lee, Seung-Hun

    2014-01-01

    Bulk magnetization, transport and neutron scattering measurements were performed to investigate the electronic and magnetic properties of a polycrystalline sample of the newly discovered ferromagnetic superconductor, CeO0:3F0:7BiS2. Ferromagnetism develops below TFM = 6.54(8) K and superconductivity is found to coexist with the ferromagnetic state below TSC 4.5 K. Inelastic neutron scattering measurements reveal a very weakly dispersive magnetic excitation at 1.8 meV that can be explained by an Ising-like spin Hamiltonian. Under application of an external magnetic eld, the direction of the magnetic moment changes from the c-axis to the ab-plane and the 1.8 meV excitation splits into two modes. A possible mechanism for the unusual magnetism and its relation to superconductivity is discussed.

  7. Peak effect and superconducting properties of SmFeAsO0.8F0.2 wires

    NASA Astrophysics Data System (ADS)

    Chen, Y. L.; Cui, Y. J.; Yang, Y.; Zhang, Y.; Wang, L.; Cheng, C. H.; Sorrell, C.; Zhao, Y.

    2008-11-01

    Ta-sheathed SmFeAsO0.8F0.2 superconducting wires with Tc = 52.5 K have been fabricated using the powder-in-tube (PIT) method and the superconducting properties of the wires have been investigated. The wires exhibit a very large intragrain critical current density at a temperature below 30 K. A peak effect with maximal Jc = 0.6 MA cm-2 at 10 K under 6 T field was observed. The peak field Hpear is strongly temperature-dependent. A severe weak-link effect depresses the development of global supercurrent owing to a very short coherence length. The wires also show a power law temperature dependence for the irreversibility line with H_{\\mathrm {irr}} \\cong (1-T/T_{\\mathrm {c}})^{1.5} . The H-T phase diagram was found to be similar to that of other superconducting cuprates.

  8. Athena MIMOS II Mössbauer spectrometer investigation

    NASA Astrophysics Data System (ADS)

    Klingelhöfer, G.; Morris, R. V.; Bernhardt, B.; Rodionov, D.; de Souza, P. A.; Squyres, S. W.; Foh, J.; Kankeleit, E.; Bonnes, U.; Gellert, R.; Schröder, C.; Linkin, S.; Evlanov, E.; Zubkov, B.; Prilutski, O.

    2003-12-01

    Mössbauer spectroscopy is a powerful tool for quantitative mineralogical analysis of Fe-bearing materials. The miniature Mössbauer spectrometer MIMOS II is a component of the Athena science payload launched to Mars in 2003 on both Mars Exploration Rover missions. The instrument has two major components: (1) a rover-based electronics board that contains power supplies, a dedicated central processing unit, memory, and associated support electronics and (2) a sensor head that is mounted at the end of the instrument deployment device (IDD) for placement of the instrument in physical contact with soil and rock. The velocity transducer operates at a nominal frequency of ~25 Hz and is equipped with two 57Co/Rh Mössbauer sources. The reference source (~5 mCi landed intensity), reference target (α-Fe2O3 plus α-Fe0), and PIN-diode detector are configured in transmission geometry and are internal to the instrument and used for its calibration. The analysis Mössbauer source (~150 mCi landed intensity) irradiates Martian surface materials with a beam diameter of ~1.4 cm. The backscatter radiation is measured by four PIN-diode detectors. Physical contact with surface materials is sensed with a switch-activated contact plate. The contact plate and reference target are instrumented with temperature sensors. Assuming ~18% Fe for Martian surface materials, experiment time is 6-12 hours during the night for quality spectra (i.e., good counting statistics); 1-2 hours is sufficient to identify and quantify the most abundant Fe-bearing phases. Data stored internal to the instrument for selectable return to Earth include Mössbauer and pulse-height analysis spectra (512 and 256 channels, respectively) for each of the five detectors in up to 13 temperature intervals (65 Mössbauer spectra), engineering data for the velocity transducer, and temperature measurements. The total data volume is ~150 kB. The mass and power consumption are ~500 g (~400 g for the sensor head) and ~2 W

  9. FINE-GRAINED PITCH ACCENT AND BOUNDARY TONE LABELING WITH PARAMETRIC F0 FEATURES

    PubMed Central

    Ananthakrishnan, Sankaranarayanan; Narayanan, Shrikanth

    2009-01-01

    Motivated by linguistic theories of prosodic categoricity, symbolic representations of prosody have recently attracted the attention of speech technologists. Categorical representations such as ToBI not only bear linguistic relevance, but also have the advantage that they can be easily modeled and integrated within applications. Since manual labeling of these categories is time-consuming and expensive, there has been significant interest in automatic prosody labeling. This paper presents a fine-grained ToBI-style prosody labeling system that makes use of features derived from RFC and TILT parameterization of F0 together with a n-gram prosodic language model for 4-way pitch accent labeling and 2-way boundary tone labeling. For this task, our system achieves pitch accent labeling accuracy of 56.4% and boundary tone labeling accuracy of 67.7% on the Boston University Radio News Corpus. PMID:19180228

  10. Design of null tests for an F/0.8 concave oblate elliptical surface

    NASA Astrophysics Data System (ADS)

    Ding, Xuezhuan; Yang, Bo; Liu, Chenglin; Wang, Xin; Liu, Yinnian

    2010-10-01

    Aspheric surfaces are widely used in aerospace sensing optic instruments. There are numerous reflecting optical system designs that call for oblate elliptical surfaces, such as secondary mirror or tertiary mirror in three mirror anastigmat (TMA). The consequence brought by increase in field of view (FOV) and speed of optical system is the decrease in F/# of aspheric surface which makes its production harder. Due to oblate ellipsoid's stigmatic points are not lined up on the optic axis, null lenses corrector is used more often than the stigmatic null test especially in low F/# aspheric surfaces test. Three types of null lenses tests for an oblate elliptical surface with aperture Φ360mm, F/0.8, conic=0.243 are presented including a new type which is modified by replacing the reference flat and null lens with one lens with reflect surface. Furthermore, sensitivity tolerances for each design are practiced.

  11. The magnetization of PrFeAsO 0.60F 0.12 superconductor

    NASA Astrophysics Data System (ADS)

    Bhoi, D.; Mandal, P.; Choudhury, P.; Dash, S.; Banerjee, A.

    2011-04-01

    The magnetization of the PrFeAsO 0.60F 0.12 polycrystalline sample has been measured as functions of temperature and magnetic field ( H). The observed total magnetization is the sum of a superconducting irreversible magnetization and a paramagnetic magnetization. Analysis of dc susceptibility χ( T) in the normal state shows that the paramagnetic component of magnetization comes from the Pr 3+ magnetic moments. The intragrain critical current density ( JL) derived from the magnetization data is large. The JL( H) curve displays a second peak which shifts towards the high-field region with decreasing temperature. In the low-field region, a plateau up to a field H* followed by a power law H-5/8 behavior of JL( H) is the characteristic of the strong pinning. A vortex phase diagram for the present superconductor has been obtained from the magnetization and resistivity data.

  12. Analysis of interdiffusion between SmFeAsO0.92F0.08 and metals for ex situ fabrication of superconducting wire

    NASA Astrophysics Data System (ADS)

    Fujioka, M.; Matoba, M.; Ozaki, T.; Takano, Y.; Kumakura, H.; Kamihara, Y.

    2011-07-01

    To find good sheath materials that react minimally with the superconducting core of iron-based superconducting wires, we investigated the reaction between polycrystalline SmFeAsO0.92F0.08 and the following seven metals: Cu, Fe, Ni, Ta, Nb, Cr and Ti. Each of the seven metals was prepared as a sheath-material candidate. The interfacial microstructures of SmFeAsO0.92F0.08 and these metal-sheath samples were analysed by an electron probe microanalyzer after annealing at 1000 °C for 20 h. Amongst the seven metal-sheath samples, we found that Cu was the best, because it reacted only very weakly with polycrystalline SmFeAsO0.92F0.08. Moreover, Cu is essential for superconducting wires as a stabilizing material. Metal sheaths made of Fe and Ni do not give rise to reaction layers, but large interdiffusion between these metals and polycrystalline SmFeAsO0.92F0.08 occurs. In contrast, metal sheaths made of Ta, Nb, Cr and Ti do form reaction layers. Their reaction layers apparently prevent electric current from flowing from the sheath material to the superconducting core. In general, through this research, Cu will be expected to be suitable not only as a stabilizing material but also as a sheath material for superconducting Sm-1111 wire fabricated by the ex situ PIT method.

  13. Magnetic properties and electronic structure of LaFeAsO0.85F0.1

    NASA Astrophysics Data System (ADS)

    Fedorchenko, A. V.; Grechnev, G. E.; Desnenko, V. A.; Panfilov, A. S.; Volkova, O. S.; Vasiliev, A. N.

    2010-03-01

    The magnetic properties of the compound LaFeAsO0.85F0.1 were investigated by measurements of the dc magnetization for different values of the magnetic field H =0.02, 1.0 and 2.0T in the temperature range 4.2-300K. Superconducting behavior was found below 26K, whereas a distinct peculiarity in the low-field dependence of the magnetic susceptibility χ(T ) was clearly observed at TM≃135K, which resembles a weak ferromagnetic (FM) response with saturation magnetic moment of about 10-4μB per formula unit at 50K. The transition at TM is presumably not governed by magnetic impurities but rather correlated with the antiferromagnetic (AFM) transition in undoped LaFeAsO at about the same temperature. We suggest that the observed magnetic properties of the LaFeAsO0.85F0.1 sample are due to an interplay of FM and AFM transitions, and are presumably related with an intrinsic feature of a small portion of the undoped LaFeAsO phase inherent in our sample. In order to shed light on the problem of magnetic instability of the LaFeAsO, ab initio DFT calculations of the electronic structure and paramagnetic susceptibility were performed within the local spin density approximation. It is shown that a V-shaped peculiarity in the density of electronic states close to the Fermi level can govern magnetic properties of LaFeAsO with fluorine doping and/or oxygen deficiency.

  14. Optical investigations of He II two phase flow

    NASA Astrophysics Data System (ADS)

    di Muoio, E.; Jager, B.; Puech, L.; Rousset, B.; Thibault, P.; van Weelderen, R.; Wolf, P. E.

    2002-05-01

    We describe the optical techniques we used to detect droplets in the HeII two phase flow of the Cryoloop experiment. These include quantitative light scattering, imaging, and laser phase sensitive anemometry and granulometry (PDPA). We demonstrate that droplets appear for vapor velocities larger than 5 m/s, and that they progressively invade the entire pipe cross section as the vapor velocity is increased. Estimates are given for the droplet size and density.

  15. Investigation of Detergent Effects on the Solution Structure of Spinach Light Harvesting Complex II

    SciTech Connect

    Cardoso, Mateus B; Smolensky, Dmitriy; Heller, William T; O'Neill, Hugh Michael

    2010-01-01

    The properties of spinach light harvesting complex II (LHC II), stabilized in the detergents Triton X-100 (TX100) and n-Octyl-{beta}-D-Glucoside (BOG), were investigated by small-angle neutron scattering (SANS). The LHC II-BOG scattering curve overlaid well with the theoretical scattering curve generated from the crystal structure of LHC II indicating that the protein preparation was in its native functional state. On the other hand, the simulated LHC II curve deviated significantly from the LHC II-TX100 experimental data. Analysis by circular dichroism spectroscopy supported the SANS analysis and showed that LHC II-TX100 is inactivated. This investigation has implications for extracting and stabilizing photosynthetic membrane proteins for the development of biohybrid photoconversion devices.

  16. Investigation of detergent effects on the solution structure of spinach Light Harvesting Complex II

    NASA Astrophysics Data System (ADS)

    Cardoso, Mateus B.; Smolensky, Dmitriy; Heller, William T.; O'Neill, Hugh

    2010-11-01

    The properties of spinach light harvesting complex II (LHC II), stabilized in the detergents Triton X-100 (TX100) and n-Octyl-β-D-Glucoside (BOG), were investigated by small-angle neutron scattering (SANS). The LHC II-BOG scattering curve overlaid well with the theoretical scattering curve generated from the crystal structure of LHC II indicating that the protein preparation was in its native functional state. On the other hand, the simulated LHC II curve deviated significantly from the LHC II-TX100 experimental data. Analysis by circular dichroism spectroscopy supported the SANS analysis and showed that LHC II-TX100 is inactivated. This investigation has implications for extracting and stabilizing photosynthetic membrane proteins for the development of biohybrid photoconversion devices.

  17. Metabolic Trade-offs in Yeast are Caused by F1F0-ATP synthase

    PubMed Central

    Nilsson, Avlant; Nielsen, Jens

    2016-01-01

    Intermediary metabolism provides living cells with free energy and precursor metabolites required for synthesizing proteins, lipids, RNA and other cellular constituents, and it is highly conserved among living species. Only a fraction of cellular protein can, however, be allocated to enzymes of intermediary metabolism and consequently metabolic trade-offs may take place. One such trade-off, aerobic fermentation, occurs in both yeast (the Crabtree effect) and cancer cells (the Warburg effect) and has been a scientific challenge for decades. Here we show, using flux balance analysis combined with in vitro measured enzyme specific activities, that fermentation is more catalytically efficient than respiration, i.e. it produces more ATP per protein mass. And that the switch to fermentation at high growth rates therefore is a consequence of a high ATP production rate, provided by a limited pool of enzymes. The catalytic efficiency is also higher for cells grown on glucose compared to galactose and ethanol, which may explain the observed differences in their growth rates. The enzyme F1F0-ATP synthase (Complex V) was found to have flux control over respiration in the model, and since it is evolutionary conserved, we expect the trade-off to occur in organisms from all kingdoms of life. PMID:26928598

  18. Recognizing the authenticity of emotional expressions: F0 contour matters when you need to know.

    PubMed

    Drolet, Matthis; Schubotz, Ricarda I; Fischer, Julia

    2014-01-01

    Authenticity of vocal emotion expression affects emotion recognition and brain activity in the so-called Theory of Mind (ToM) network, which is implied in the ability to explain and predict behavior by attributing mental states to other individuals. Exploiting the variability of the fundamental frequency (F0 contour), which varies more (higher contour) in play-acted expressions than authentic ones, we examined whether contour biases explicit categorization toward a particular authenticity or emotion category. Moreover, we tested whether contour modulates blood-oxygen-level dependent (BOLD) response in the ToM network and explored the role of task as a top-down modulator. The effects of contour on BOLD signal were analyzed by contrasting high and low contour stimuli within two previous fMRI studies that implemented emotion and authenticity rating tasks. Participants preferentially categorized higher contour stimuli as play-acted and lower contour stimuli as sad. Higher contour was found to up-regulate activation task-independently in the primary auditory cortex. Stimulus contour and task were found to interact in a network including medial prefrontal cortex, with an increase in BOLD signal for low-contour stimuli during explicit perception of authenticity and an increase for high-contour stimuli during explicit perception of emotion. Contour-induced BOLD effects appear to be purely stimulus-driven in early auditory and intonation perception, while being strongly task-dependent in regions involved in higher cognition.

  19. Recognizing the authenticity of emotional expressions: F0 contour matters when you need to know

    PubMed Central

    Drolet, Matthis; Schubotz, Ricarda I.; Fischer, Julia

    2014-01-01

    Authenticity of vocal emotion expression affects emotion recognition and brain activity in the so-called Theory of Mind (ToM) network, which is implied in the ability to explain and predict behavior by attributing mental states to other individuals. Exploiting the variability of the fundamental frequency (F0 contour), which varies more (higher contour) in play-acted expressions than authentic ones, we examined whether contour biases explicit categorization toward a particular authenticity or emotion category. Moreover, we tested whether contour modulates blood-oxygen-level dependent (BOLD) response in the ToM network and explored the role of task as a top-down modulator. The effects of contour on BOLD signal were analyzed by contrasting high and low contour stimuli within two previous fMRI studies that implemented emotion and authenticity rating tasks. Participants preferentially categorized higher contour stimuli as play-acted and lower contour stimuli as sad. Higher contour was found to up-regulate activation task-independently in the primary auditory cortex. Stimulus contour and task were found to interact in a network including medial prefrontal cortex, with an increase in BOLD signal for low-contour stimuli during explicit perception of authenticity and an increase for high-contour stimuli during explicit perception of emotion. Contour-induced BOLD effects appear to be purely stimulus-driven in early auditory and intonation perception, while being strongly task-dependent in regions involved in higher cognition. PMID:24701202

  20. Design of null lens system for f/0.5 hyperboloid mirror

    NASA Astrophysics Data System (ADS)

    Wang, Zi-wu; Guo, Pei-ji; Chen, Xi; Peng, Ling-jie

    2016-10-01

    The aspherical mirror surface quality testing by using compensation null lens in interferometer is described in this paper. For 310mm, f/0.5 hyperboloid mirror microcrystalline components, based on the theory of aberration compensation, a kind of null lens system which is composed of three pieces of spherical lens is developed. A certain amount of spherical aberration is introduced to the null lens for compensating the deviation of aspheric surface in a normal direction. The design result shows that the primary aberration and the senior aberration are balanced well, the MTF is closed to the diffraction limit and the residual wave aberration (RMS) is less than 0.004λ (λ=0.6328μm). Every indicators of the system meets the requirements of high precision detection of null lens system design. In this paper, the errors caused by the manufacturing, testing and assembling of the null lens system are analyzed. Those errors can be divided into the symmetric error and the asymmetric error. Using the correction method, the influence of the asymmetric error is minimized which seemed bigger than the asymmetric one. Finally, analysis results show that the total residual wave aberration of the system is less than 0.0072λ, which satisfies the requirement of aspheric testing. This null lens system has been applied to aspheric processing.

  1. Search for the glueball candidates f0(1500) and fJ(1710) in /γγ collisions

    NASA Astrophysics Data System (ADS)

    Barate, R.; Decamp, D.; Ghez, P.; Goy, C.; Lees, J.-P.; Merle, E.; Minard, M.-N.; Pietrzyk, B.; Alemany, R.; Bravo, S.; Casado, M. P.; Chmeissani, M.; Crespo, J. M.; Fernandez, E.; Fernandez-Bosman, M.; Garrido, L.; Graugès, E.; Juste, A.; Martinez, M.; Merino, G.; Miquel, R.; Mir, L. M.; Pacheco, A.; Riu, I.; Ruiz, H.; Colaleo, A.; Creanza, D.; de Palma, M.; Iaselli, G.; Maggi, G.; Maggi, M.; Nuzzo, S.; Ranieri, A.; Raso, G.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Tricomi, A.; Zito, G.; Huang, X.; Lin, J.; Ouyang, Q.; Wang, T.; Xie, Y.; Xu, R.; Xue, S.; Zhang, J.; Zhang, L.; Zhao, W.; Abbaneo, D.; Boix, G.; Buchmüller, O.; Cattaneo, M.; Cerutti, F.; Ciulli, V.; Dissertori, G.; Drevermann, H.; Forty, R. W.; Frank, M.; Greening, T. C.; Halley, A. W.; Hansen, J. B.; Harvey, J.; Janot, P.; Jost, B.; Lehraus, I.; Leroy, O.; Mato, P.; Minten, A.; Moutoussi, A.; Ranjard, F.; Rolandi, L.; Schlatter, D.; Schmitt, M.; Schneider, O.; Spagnolo, P.; Tejessy, W.; Teubert, F.; Tournefier, E.; Wright, A. E.; Ajaltouni, Z.; Badaud, F.; Chazelle, G.; Deschamps, O.; Falvard, A.; Ferdi, C.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Monteil, S.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Nilsson, B. S.; Rensch, B.; Wäänänen, A.; Daskalakis, G.; Kyriakis, A.; Markou, C.; Simopoulou, E.; Siotis, I.; Vayaki, A.; Blondel, A.; Bonneaud, G.; Brient, J.-C.; Rougé, A.; Rumpf, M.; Swynghedauw, M.; Verderi, M.; Videau, H.; Focardi, E.; Parrini, G.; Zachariadou, K.; Corden, M.; Georgiopoulos, C.; Antonelli, A.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Chiarella, V.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Curtis, L.; Lynch, J. G.; Negus, P.; O'Shea, V.; Raine, C.; Teixeira-Dias, P.; Thompson, A. S.; Cavanaugh, R.; Dhamotharan, S.; Geweniger, C.; Hanke, P.; Hansper, G.; Hepp, V.; Kluge, E. E.; Putzer, A.; Sommer, J.; Tittel, K.; Werner, S.; Wunsch, M.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Dornan, P. J.; Girone, M.; Goodsir, S.; Martin, E. B.; Marinelli, N.; Sciabà, A.; Sedgbeer, J. K.; Thomson, E.; Williams, M. D.; Ghete, V. M.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Buck, P. G.; Finch, A. J.; Foster, F.; Hughes, G.; Jones, R. W. L.; Robertson, N. A.; Williams, M. I.; Giehl, I.; Jakobs, K.; Kleinknecht, K.; Quast, G.; Renk, B.; Rohne, E.; Sander, H.-G.; Wachsmuth, H.; Zeitnitz, C.; Aubert, J. J.; Bonissent, A.; Carr, J.; Coyle, P.; Payre, P.; Rousseau, D.; Aleppo, M.; Antonelli, M.; Ragusa, F.; Büscher, V.; Dietl, H.; Ganis, G.; Hüttmann, K.; Lütjens, G.; Mannert, C.; Männer, W.; Moser, H.-G.; Schael, S.; Settles, R.; Seywerd, H.; Stenzel, H.; Wiedenmann, W.; Wolf, G.; Azzurri, P.; Boucrot, J.; Callot, O.; Chen, S.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, P.; Jacholkowska, A.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zerwas, D.; Bagliesi, G.; Boccali, T.; Bozzi, C.; Calderini, G.; Dell'Orso, R.; Ferrante, I.; Foà, L.; Giassi, A.; Gregorio, A.; Ligabue, F.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Sguazzoni, G.; Tenchini, R.; Venturi, A.; Verdini, P. G.; Blair, G. A.; Cowan, G.; Green, M. G.; Medcalf, T.; Strong, J. A.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Norton, P. R.; Thompson, J. C.; Tomalin, I. R.; Bloch-Devaux, B.; Colas, P.; Emery, S.; Kozanecki, W.; Lançon, E.; Lemaire, M.-C.; Locci, E.; Perez, P.; Rander, J.; Renardy, J.-F.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Trabelsi, A.; Vallage, B.; Black, S. N.; Dann, J. H.; Johnson, R. P.; Kim, H. Y.; Konstantinidis, N.; Litke, A. M.; McNeil, M. A.; Taylor, G.; Booth, C. N.; Cartwright, S.; Combley, F.; Lehto, M.; Thompson, L. F.; Affholderbach, K.; Böhrer, A.; Brandt, S.; Grupen, C.; Hess, J.; Misiejuk, A.; Prange, G.; Sieler, U.; Giannini, G.; Gobbo, B.; Rothberg, J.; Wasserbaech, S.; Armstrong, S. R.; Elmer, P.; Ferguson, D. P. S.; Gao, Y.; González, S.; Hayes, O. J.; Hu, H.; Jin, S.; Kile, J.; McNamara, P. A., III; Nielsen, J.; Orejudos, W.; Pan, Y. B.; Saadi, Y.; Scott, I. J.; Walsh, J.; von Wimmersperg-Toeller, J. H.; Wu, S. L.; Wu, X.; Zobernig, G.

    2000-01-01

    Data taken with the ALEPH detector at LEP1 have been used to search for /γγ production of the glueball candidates f0(1500) and fJ(1710) via their decay to π+π-. No signal is observed and upper limits to the product of /γγ width and π+π- branching ratio of the f0(1500) and the fJ(1710) have been measured to beΓ(γγ-- >f0(1500)).BR(f0(1500)-- >π+π-)<0.31keV and Γ(γγ-- >fJ(1710)).BR(fJ(1710)-- >π+π-)<0.55keV at 95% confidence level.

  2. American Material Culture: Investigating a World War II Trash Dump

    SciTech Connect

    Julie Braun

    2005-10-01

    The Idaho National Laboratory: An Historical Trash Trove Historians and archaeologists love trash, the older the better. Sometimes these researchers find their passion in unexpected places. In this presentation, the treasures found in a large historic dump that lies relatively untouched in the middle of the Idaho National Laboratory (INL) will be described. The U.S. military used the central portion of the INL as one of only six naval proving grounds during World War II. They dumped trash in dry irrigation canals during and after their wartime activities and shortly before the federal government designated this arid and desolate place as the nation’s nuclear reactor testing station in 1949. When read critically and combined with memories and photographs, the 60-year old trash provides a glimpse into 1940s’ culture and the everyday lives of ordinary people who lived and worked during this time on Idaho’s desert. Thanks to priceless stories, hours of research, and the ability to read the language of historic artifacts, the dump was turned from just another trash heap into a treasure trove of 1940s memorabilia. Such studies of American material culture serve to fire our imaginations, enrich our understanding of past practices, and humanize history. Historical archaeology provides opportunities to integrate inanimate objects with animated narrative and, the more recent the artifacts, the more human the stories they can tell.

  3. Numerical Investigation of Thermal Counterflow of He II Past Cylinders

    NASA Astrophysics Data System (ADS)

    Soulaine, Cyprien; Quintard, Michel; Baudouy, Bertrand; Van Weelderen, Rob

    2017-02-01

    We investigate numerically, for the first time, the thermal counterflow of superfluid helium past a cylinder by solving with a finite volume method the complete so-called two-fluid model. In agreement with existing experimental results, we obtain symmetrical eddies both up- and downstream of the obstacle. The generation of these eddies is a complex transient phenomenon that involves the friction of the normal fluid component with the solid walls and the mutual friction between the superfluid and normal components. Implications for flow in a more realistic porous medium are also investigated.

  4. Investigation of resistive losses in type II superconductors

    NASA Astrophysics Data System (ADS)

    Benapfl, Brendan W.

    For low-TC materials, the superconducting transition temperature (TC) is depressed by the application of a magnetic field. In contrast, one of the remarkable features of cuprate high-TC materials is that the superconducting transition is broadened by the application of a magnetic field. Tinkham presented a model for the field-dependent resistive transition of high-T C materials, arising from "phase slippage at a complicated network of channels." Coffey & Clem did not include this field-broadening effect in their sophisticated model for the field and temperature dependence of the surface resistance in type-II superconductors. From the model by Lee & Stroud, treating Josephson Junction-coupled superconducting segments, it is concluded that doped, layered superconductors are certain to have a field-broadened superconducting transition. This effect can be identified by measurements of the resistivity as a function of temperature, magnetic field strength, angle of field with respect to the crystal axis as well as with respect to an induced current density. The iron pnictide materials such as Ba0.6K0.4Fe2As2 (BaK122) have chemical layers with different compositions, differentiating them from elemental type-II superconductors such as niobium, and also from cuprates, by the absence of copper. Experimental data on BaK122 indicate a field-broadened transition in conjunction with a field-depressed superconducting transition temperature. In this work, techniques associated with Electron Spin Resonance (ESR) spectroscopy were used to measure the temperature and field-induced changes in the surface resistance of single-crystal BaK122 samples. In addition, polycrystalline foils of niobium and a NbTi (70/30) alloy were measured using the same techniques to provide comparison. Measurements were taken as a function of applied magnetic field, temperature, rf field intensity, and angle of the applied field with respect to the rf-induced current. BaK122 sample field-dependent surface

  5. Unconventional Superconductivity in the BiS2 -Based Layered Superconductor NdO0.71F0.29BiS2

    NASA Astrophysics Data System (ADS)

    Ota, Yuichi; Okazaki, Kozo; Yamamoto, Haruyoshi Q.; Yamamoto, Takashi; Watanabe, Shuntaro; Chen, Chuangtian; Nagao, Masanori; Watauchi, Satoshi; Tanaka, Isao; Takano, Yoshihiko; Shin, Shik

    2017-04-01

    We investigate the superconducting-gap anisotropy in one of the recently discovered BiS2 -based superconductors, NdO0.71F0.29BiS2 (Tc˜5 K ), using laser-based angle-resolved photoemission spectroscopy. Whereas the previously discovered high-Tc superconductors such as copper oxides and iron-based superconductors, which are believed to have unconventional superconducting mechanisms, have 3 d electrons in their conduction bands, the conduction band of BiS2 -based superconductors mainly consists of Bi 6 p electrons, and, hence, the conventional superconducting mechanism might be expected. Contrary to this expectation, we observe a strongly anisotropic superconducting gap. This result strongly suggests that the pairing mechanism for NdO0.71F0.29BiS2 is an unconventional one and we attribute the observed anisotropy to competitive or cooperative multiple paring interactions.

  6. Unconventional Superconductivity in the BiS_{2}-Based Layered Superconductor NdO_{0.71}F_{0.29}BiS_{2}.

    PubMed

    Ota, Yuichi; Okazaki, Kozo; Yamamoto, Haruyoshi Q; Yamamoto, Takashi; Watanabe, Shuntaro; Chen, Chuangtian; Nagao, Masanori; Watauchi, Satoshi; Tanaka, Isao; Takano, Yoshihiko; Shin, Shik

    2017-04-21

    We investigate the superconducting-gap anisotropy in one of the recently discovered BiS_{2}-based superconductors, NdO_{0.71}F_{0.29}BiS_{2} (T_{c}∼5  K), using laser-based angle-resolved photoemission spectroscopy. Whereas the previously discovered high-T_{c} superconductors such as copper oxides and iron-based superconductors, which are believed to have unconventional superconducting mechanisms, have 3d electrons in their conduction bands, the conduction band of BiS_{2}-based superconductors mainly consists of Bi 6p electrons, and, hence, the conventional superconducting mechanism might be expected. Contrary to this expectation, we observe a strongly anisotropic superconducting gap. This result strongly suggests that the pairing mechanism for NdO_{0.71}F_{0.29}BiS_{2} is an unconventional one and we attribute the observed anisotropy to competitive or cooperative multiple paring interactions.

  7. Fibre reinforced composite dental bridge. Part II: Numerical investigation.

    PubMed

    Li, W; Swain, M V; Li, Q; Ironside, J; Steven, G P

    2004-09-01

    Motivated by the clinical success and limitations on experimental investigation of the fibre-reinforced composite dental bridge, this paper aims at providing a numerical investigation into the bridge structure. The finite element (FE) model adopted here is constructed from computer tomography images of a physical bridge specimen. The stress and strain distributions in the bridge structure especially in the bonding interfaces are analyzed in detail. The peak stresses and their variations with the different bridge designs are evaluated. Due to the lower bond strengths of adhesives and the high stress concentration in the pontic-abutment interface, the likelihood of failure in the interface is predicted by finite element analysis. The validity of the numerical results is established by a good agreement between the FE prediction and the tests in the load-deflection responses, the structural stiffness as well as the failure location of the composite dental bridge.

  8. Archaeological Investigations in the Upper Tombigbee Valley, Mississippi: Phase II.

    DTIC Science & Technology

    1983-01-01

    previous year. Stripping allowed quick access to a cemented manganese | stratum which effectively sealed the Early Archaic component beneath it. A...I investigators (IV; Bense 1982: Chapter 10, * Figure 10.6), and judged to contain the sealed , intact early Archaic cultural deposits. During the...phase. Feature 4: a historic trash dumping area near what had been the southwest area of the ’old house. Mixed in with plastic, glass , nails, crockery

  9. Regulation of F0F1-ATPase from Synechocystis sp. PCC 6803 by γ and ϵ Subunits Is Significant for Light/Dark Adaptation*

    PubMed Central

    Imashimizu, Mari; Bernát, Gábor; Sunamura, Ei-Ichiro; Broekmans, Martin; Konno, Hiroki; Isato, Kota; Rögner, Matthias; Hisabori, Toru

    2011-01-01

    The γ and ϵ subunits of F0F1-ATP synthase from photosynthetic organisms display unique properties not found in other organisms. Although the γ subunit of both chloroplast and cyanobacterial F0F1 contains an extra amino acid segment whose deletion results in a high ATP hydrolysis activity (Sunamura, E., Konno, H., Imashimizu-Kobayashi, M., Sugano, Y., and Hisabori, T. (2010) Plant Cell Physiol. 51, 855–865), its ϵ subunit strongly inhibits ATP hydrolysis activity. To understand the physiological significance of these phenomena, we studied mutant strains with (i) a C-terminally truncated ϵ (ϵΔC), (ii) γ lacking the inserted sequence (γΔ198–222), and (iii) a double mutation of (i) and (ii) in Synechocystis sp. PCC 6803. Although thylakoid membranes from the ϵΔC strain showed higher ATP hydrolysis and lower ATP synthesis activities than those of the wild type, no significant difference was observed in growth rate and in intracellular ATP level both under light conditions and during light-dark cycles. However, both the ϵΔC and γΔ198–222 and the double mutant strains showed a lower intracellular ATP level and lower cell viability under prolonged dark incubation compared with the wild type. These data suggest that internal inhibition of ATP hydrolysis activity is very important for cyanobacteria that are exposed to prolonged dark adaptation and, in general, for the survival of photosynthetic organisms in an ever-changing environment. PMID:21610078

  10. Mechanism of local anesthetic effect. Involvement of F0 in the inhibition of mitochondrial ATP synthase by phenothiazines.

    PubMed

    Dabbeni-Sala, F; Palatini, P

    1990-02-02

    The mechanism whereby tertiary amine local anesthetics affect the activity of membrane proteins was investigated by studying the interaction of phenothiazines with mitochondrial ATP synthase. These drugs caused inhibition of the activity of the membrane-bound enzyme at concentrations that do not perturb the phospholipid bilayer. The inhibitory effect appeared consequent to interaction with multiple sites located on both the F1 and the F0 components of the enzyme complex, since: (a) Dixon plots were parabolic; (b) the membrane-bound enzyme was more sensitive to the drug effect than the isolated F1 component; (c) conditions that decreased oligomycin sensitivity also decreased the sensitivity to phenothiazines; (d) irreversible binding of photochemically activated phenothiazines to the ATP synthase complex, followed by detachment of the F1 moiety and reconstitution with purified F1 resulted in an inhibited enzyme complex. These data are interpreted as indicating that tertiary amine local anesthetics affect the activity of membrane proteins by interacting with hydrophobic sites located on both their integral and peripheral domains.

  11. DSCS II. Battery Anomaly Investigation Satellites 9437 and 9438.

    DTIC Science & Technology

    1980-04-25

    and is approved for publica- tion. Publication of this report does not constitute Air Force approval of the report’s findings or conclusions . It is...Contract F04701-77-C-0118 TRW Defense and Space Systems Group One Space Park Redondo Beach, California 90278 CONTENTS Page 1. SUMMARY AND CONCLUSIONS 1-1...1.1 Scope 1-1 1.2 Anomaly Description 1-I 1.3 Anomaly Investigations 1-1 1.4 Conclusions 1-1 2. BACKGROUND 2-1 2.1 Power Subsystem 2-1 2.2 Orbital

  12. F+0 diuretic protocol is superior to F-15 and F+20 for nuclear renogram in children

    PubMed Central

    Babu, Ramesh; Venkatsubramaniam, Dhandapani; Venkatachalapathy, Easwaramoorthy

    2015-01-01

    Introduction: We compare the outcomes of three different diuretic protocols for renograms in children with hydronephrosis. Materials and Methods: Between August 2011 and July 2013, 148 diuretic renograms were performed to evaluate unilateral grade 3–4 hydronephrosis (reflux, posterior urethral valves, post-pyeloplasty status excluded). Patients were allotted into three groups based on the timing of diuretic administration: Diuretic given 15 min before (F-15), at the same time as (F + 0) and 20 min after (F + 20) radionuclide administration. Dynamic images and renogram curves were inspected to identify in each group (1) number of equivocal curves and (2) number of interrupted studies due to patient movement/discomfort/voiding. Statistical significance was determined by the Fisher exact test. Results: There was no significant difference in age/sex distribution between groups F-15 (n = 35), F + 0 (n = 38) and F + 20 (n = 75). The number of equivocal curves was significantly less in F + 0 (2/38) and F-15 (3/35) compared with F + 20 (20/75). The number of interrupted studies was significantly less in F + 0 (2/38) compared with F-15 (9/35) and F + 20 (18/75). Conclusion: The F + 0 and F-15 protocols are superior to the F + 20 protocol in reducing the number of equivocal curves, while the F + 0 protocol is superior to the other two in reducing interruptions due to patient movement or voiding. F + 0 is the diuretic protocol of choice for renogram in children. PMID:26166970

  13. Investigations on the binding of human hemoglobin with orange I and orange II.

    PubMed

    Wang, Yan-Qing; Zhang, Hong-Mei

    2012-08-01

    The interactions between human hemoglobin and orange I (or orange II) were investigated by UV/vis absorption, circular dichroism, fluorescence spectra techniques, and molecular modeling method. Orange I and orange II effectively quenched the intrinsic fluorescence of human hemoglobin by static quenching. The processes of the binding orange I and orange II on human hemoglobin were spontaneous molecular interaction procedure with hydrogen bonds, van der Waals force, hydrophobic and electrostatic interactions according to van't Hoff equation and molecular modeling. There is a single class of binding site of orange I (orange II) in human hemoglobin and the molecular modeling study shows that orange I and orange II are dipped into α(2) chain. The results of CD, synchronous fluorescence and three-dimensional fluorescence spectra indicated a small loss of α-helical secondary structure of human hemoglobin induced by orange I and orange II.

  14. Investigation of Damping Liquids for Aircraft Instruments : II

    NASA Technical Reports Server (NTRS)

    Houseman, M R; Keulegan, G H

    1932-01-01

    Data are presented on the kinematic viscosity, in the temperature range -50 degrees to +30 degrees C. of pure liquids and of solutions of animal oils, vegetable oils, mineral oils, glycerine, and ethylene glycol in various low freezing point solvents. It is shown that the thermal coefficient of kinematic viscosity as a function of the kinematic viscosity of the solutions of glycerine and ethylene glycol in alcohols is practically independent of the temperature and the chemical composition of the individual liquids. This is similarly true for the mineral oil group and, for a limited temperature interval, for the pure animal and vegetable oils. The efficiency of naphthol, hydroquinone, and diphenylamine to inhibit the change of viscosity of poppyseed and linseed oils was also investigated.

  15. Detailed aeromagnetic investigation of the Arctic Basin. II

    NASA Technical Reports Server (NTRS)

    Taylor, P. T.; Kovacs, L. C.; Vogt, P. R.; Johnson, G. L.

    1981-01-01

    Remote sensing techniques must be employed to determine the nature of the regional geologic and tectonic structure of the Arctic Basin. Magnetic measurements from aircraft are the most commonly used method. Since 1972 the U.S. Navy has been engaged in a long-term program of mapping, in relative detail, the earth's magnetic field over that portion of the Arctic Basin accessible to the P3 aircraft. A description is presented of the results of the 1977 and 1978 field efforts. The description represents a continuation of an investigation reported by Vogt et al. (1979). The efforts currently considered were directed towards understanding the nature, age, and origin of the major physiolographic features of the western Arctic Basin. Particular attention was given to the Canada and Makarov basins (Fletcher Abyssal Plain) and the Alpha Ridge. The aeromagnetic data are interpreted with respect to the theory of origin presented by Carey (1958).

  16. [Air conducted ocular VEMP: II. First clinical investigations].

    PubMed

    Walther, L E; Schaaf, H; Sommer, D; Hörmann, K

    2011-10-01

    Vestibular-evoked myogenic potentials (VEMP) are widely used to assess vestibular function. Air conducted (AC) cervical VEMP (cVEMP) reflect sacculus and inferior vestibular nerve function. Ocular VEMP (oVEMP) however has been hardly examined up to now. In recent studies it has been assumed that AC oVEMP probably reflects superior vestibular nerve function. The aim of this pilot study was to evaluate clinical application of the AC oVEMP. AC oVEMP were recorded in patients with peripheral vestibular disorders (n=21). In addition thermal irritation and head impulse test were performed and AC cVEMP were recorded. For intense AC-sound stimulation tone bursts (500 Hz) with 100 dB nHL were used. In peripheral vestibular disorders AC oVEMP and AC cVEMP could be classified into: • type 1 (inferior vestibular neuritis) with loss of AC oVEMP but normal AC cVEMP, • type 2, probable type of superior vestibular neuritis, showing present AC cVEMP but loss of AC oVEMP, • type 3, probable complete vestibular neuritis, without AC oVEMP and AC cVEMP. AC oVEMP may be used as an appropriate test for clinical investigation in patients with vestibular disorders. AC oVEMP is an additional, essential test for assessing otolith function beside AC cVEMP. Further vestibular test are necessary for precise clinical interpretation. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Single-Site Palladium(II) Catalyst for Oxidative Heck Reaction: Catalytic Performance and Kinetic Investigations

    SciTech Connect

    Duan, Hui; Li, Mengyang; Zhang, Guanghui; Gallagher, James R.; Huang, Zhiliang; Sun, Yu; Luo, Zhong; Chen, Hongzhong; Miller, Jeffrey T.; Zou, Ruqiang; Lei, Aiwen; Zhao, Yanli

    2015-01-01

    ABSTRACT: The development of organometallic single-site catalysts (SSCs) has inspired the designs of new heterogeneous catalysts with high efficiency. Nevertheless, the application of SSCs in certain modern organic reactions, such as C-C bond formation reactions, has still been less investigated. In this study, a single-site Pd(II) catalyst was developed, where 2,2'-bipyridine-grafted periodic mesoporous organosilica (PMO) was employed as the support of a Pd(II) complex. The overall performance of the single-site Pd(II) catalyst in the oxidative Heck reaction was then investigated. The investigation results show that the catalyst displays over 99% selectivity for the product formation with high reaction yield. Kinetic profiles further confirm its high catalytic efficiency, showing that the rate constant is nearly 40 times higher than that for the free Pd(II) salt. X-ray absorption spectroscopy reveals that the catalyst has remarkable lifetime and recyclability.

  18. THE SURVEY OF LINES IN M31 (SLIM): INVESTIGATING THE ORIGINS OF [C II] EMISSION

    SciTech Connect

    Kapala, M. J.; Sandstrom, K.; Groves, B.; Kreckel, K.; Schinnerer, E.; Walter, F.; Fouesneau, M.; Croxall, K.; Dalcanton, J.; Leroy, A.

    2015-01-01

    The [C II] 158 μm line is one of the strongest emission lines observed in star-forming galaxies and has been empirically measured to correlate with the star-formation rate (SFR) globally and on kiloparsec scales. However, because of the multiphase origins of [C II], one might expect this relation to break down at small scales. We investigate the origins of [C II] emission by examining high spatial resolution observations of [C II] in M31 with the Survey of Lines in M31. We present five ∼700 × 700 pc (3' × 3') fields mapping the [C II] emission, Hα emission, and the ancillary infrared (IR) data. We spatially separate star-forming regions from diffuse gas and dust emission on ∼50 pc scales. We find that the [C II]-SFR correlation holds even at these scales, although the relation typically has a flatter slope than found at larger (kiloparsec) scales. While the Hα emission in M31 is concentrated in the SFR regions, we find that a significant amount (∼20%-90%) of the [C II] emission comes from outside star-forming regions and that the total IR emission (TIR) has the highest diffuse fraction of all SFR tracers. We find a weak correlation of the [C II]/TIR to dust color in each field and find a large-scale trend of increasing [C II]/TIR with galactocentric radius. The differences in the relative diffuse fractions of [C II], Hα, and IR tracers are likely caused by a combination of energetic photon leakage from H II regions and heating by the diffuse radiation field arising from older (B-star) stellar populations. However, we find that by averaging our measurements over kiloparsec scales, these effects are minimized, and the relation between [C II] and SFR found in other nearby galaxy studies is retrieved.

  19. Mitochondrial F0F1-ATP synthase is a molecular target of 3-iodothyronamine, an endogenous metabolite of thyroid hormone

    PubMed Central

    Cumero, S; Fogolari, F; Domenis, R; Zucchi, R; Mavelli, I; Contessi, S

    2012-01-01

    BACKGROUND AND PURPOSE 3-iodothyronamine (T1AM) is a metabolite of thyroid hormone acting as a signalling molecule via non-genomic effectors and can reach intracellular targets. Because of the importance of mitochondrial F0F1-ATP synthase as a drug target, here we evaluated interactions of T1AM with this enzyme. EXPERIMENTAL APPROACH Kinetic analyses were performed on F0F1-ATP synthase in sub-mitochondrial particles and soluble F1-ATPase. Activity assays and immunodetection of the inhibitor protein IF1 were used and combined with molecular docking analyses. Effects of T1AM on H9c2 cardiomyocytes were measured by in situ respirometric analysis. KEY RESULTS T1AM was a non-competitive inhibitor of F0F1-ATP synthase whose binding was mutually exclusive with that of the inhibitors IF1 and aurovertin B. Both kinetic and docking analyses were consistent with two different binding sites for T1AM. At low nanomolar concentrations, T1AM bound to a high-affinity region most likely located within the IF1 binding site, causing IF1 release. At higher concentrations, T1AM bound to a low affinity-region probably located within the aurovertin binding cavity and inhibited enzyme activity. Low nanomolar concentrations of T1AM increased ADP-stimulated mitochondrial respiration in cardiomyocytes, indicating activation of F0F1-ATP synthase consistent with displacement of endogenous IF1,, reinforcing the in vitro results. CONCLUSIONS AND IMPLICATIONS Effects of T1AM on F0F1-ATP synthase were twofold: IF1 displacement and enzyme inhibition. By targeting F0F1-ATP synthase within mitochondria, T1AM might affect cell bioenergetics with a positive effect on mitochondrial energy production at low, endogenous, concentrations. T1AM putative binding locations overlapping with IF1 and aurovertin binding sites are described. PMID:22452346

  20. Modulation of F0F1-ATP synthase activity by cyclophilin D regulates matrix adenine nucleotide levels

    PubMed Central

    Chinopoulos, Christos; Konràd, Csaba; Kiss, Gergely; Metelkin, Eugeniy; Töröcsik, Beata; Zhang, Steven F.; Starkov, Anatoly A.

    2011-01-01

    Cyclophilin D was recently shown to bind to and decrease the activity of F0F1-ATP synthase in submitochondrial particles and permeabilized mitochondria (Giorgio et al. 2009, J Biol Chem, 284:33982). Cyclophilin D binding decreased both the ATP synthesis and hydrolysis rates. Here, we reaffirm these findings by demonstrating that in intact mouse liver mitochondria energized by ATP, absence of cyclophilin D or presence of cyclosporin A led to a decrease in the extent of uncoupler-induced depolarization. Accordingly, in substrate-energized mitochondria an increase in F0F1-ATP synthase activity mediated by a relief of inhibition by cyclophilin D was evident as slightly increased respiration rates during arsenolysis. However, the modulation of F0F1-ATP synthase by cyclophilin D did not increase the ANT-mediated ATP efflux rate in energized mitochondria or the ATP influx rate in de-energized mitochondria. The lack of effect of cyclophilin D on the ANT-mediated adenine nucleotide exchange rate was attributed to the ~2.2 times lower flux control coefficient of the F0F1-ATP synthase than that of ANT, deduced from measurements of adenine nucleotide flux rates in intact mitochondria. These findings were further supported by a recent kinetic model of the mitochondrial phosphorylation system, suggesting that a ~30% change in F0F1-ATP synthase activity in fully energized or fully deenergized mitochondria affects ADP-ATP exchange rate mediated by the ANT in the range of 1.38-1.7%. We conclude that in mitochondria exhibiting intact inner membranes, the absence of cyclophilin D or inhibition of its binding to F0F1-ATP synthase by cyclosporin A will affect only matrix adenine nucleotides levels. PMID:21281446

  1. Modulation of F0F1-ATP synthase activity by cyclophilin D regulates matrix adenine nucleotide levels.

    PubMed

    Chinopoulos, Christos; Konràd, Csaba; Kiss, Gergely; Metelkin, Eugeniy; Töröcsik, Beata; Zhang, Steven F; Starkov, Anatoly A

    2011-04-01

    Cyclophilin D was recently shown to bind to and decrease the activity of F(0)F(1)-ATP synthase in submitochondrial particles and permeabilized mitochondria [Giorgio V et al. (2009) J Biol Chem, 284, 33982-33988]. Cyclophilin D binding decreased both ATP synthesis and hydrolysis rates. In the present study, we reaffirm these findings by demonstrating that, in intact mouse liver mitochondria energized by ATP, the absence of cyclophilin D or the presence of cyclosporin A led to a decrease in the extent of uncoupler-induced depolarization. Accordingly, in substrate-energized mitochondria, an increase in F(0)F(1)-ATP synthase activity mediated by a relief of inhibition by cyclophilin D was evident in the form of slightly increased respiration rates during arsenolysis. However, the modulation of F(0)F(1)-ATP synthase by cyclophilin D did not increase the adenine nucleotide translocase (ANT)-mediated ATP efflux rate in energized mitochondria or the ATP influx rate in de-energized mitochondria. The lack of an effect of cyclophilin D on the ANT-mediated adenine nucleotide exchange rate was attributed to the ∼ 2.2-fold lower flux control coefficient of the F(0)F(1)-ATP synthase than that of ANT, as deduced from measurements of adenine nucleotide flux rates in intact mitochondria. These findings were further supported by a recent kinetic model of the mitochondrial phosphorylation system, suggesting that an ∼ 30% change in F(0)F(1)-ATP synthase activity in fully energized or fully de-energized mitochondria affects the ADP-ATP exchange rate mediated by the ANT in the range 1.38-1.7%. We conclude that, in mitochondria exhibiting intact inner membranes, the absence of cyclophilin D or the inhibition of its binding to F(0)F(1)-ATP synthase by cyclosporin A will affect only matrix adenine nucleotides levels. © 2011 The Authors Journal compilation © 2011 FEBS.

  2. Investigations of the Nature of Zn(II) -Si(II) Bonds.

    PubMed

    Schäfer, Sebastian; Köppe, Ralf; Roesky, Peter W

    2016-05-17

    A series of zinc(II) silylenes was prepared by using the silylene {PhC(NtBu)2 }(C5 Me5 )Si. Whereas reaction of the silylene with ZnX2 (X=Cl, I) gave the halide-bridged dimers [{PhC(NtBu)2 }(C5 Me5 )SiZnX(μ-X)]2 , with ZnR2 (R=Ph, Et, C6 F5 ) as reagent the monomers [{PhC(NtBu)2 }(C5 Me5 )SiZnR2 ] were obtained. The stability of the complexes and the Zn-Si bond lengths clearly depend on the substitution pattern of the zinc atom. Electron-withdrawing groups stabilize these adducts, whereas electron-donating groups destabilize them. This could be rationalized by quantum chemical calculations. Two different bonding modes in these molecules were identified, which are responsible for the differences in reactivity: 1) strong polar Zn-Si single bonds with short Zn-Si distances, Zn-Si force constants close to that of a classical single bond, and strong binding energy (ca. 2.39 Å, 1.33 mdyn Å(-1) , and 200 kJ mol(-1) ), which suggest an ion pair consisting of a silyl cation with a Zn-Si single bond; 2) relatively weak donor-acceptor Zn-Si bonds with long Zn-Si distances, low Zn-Si force constants, and weak binding energy (ca. 2.49 Å, 0.89 mdyn Å(-1) , and 115 kJ mol(-1) ), which can be interpreted as a silylene-zinc adduct.

  3. Magnetization and NMR studies in SmFeAsO0.86F0.14

    NASA Astrophysics Data System (ADS)

    Ghoshray, Amitabha; Majumder, Mayukh; Poddar, Asok; Mazumdar, Chandan; Ghoshray, Kajal; Berardan, David

    2012-06-01

    The Physical properties along with NMR measurements in SmFeAsO0.86F0.14 have been carried out. Superconducting transition TC (onset) remains invariant even under a magnetic field of 7 T. 75As NMR signal could not be measured below 180K in both SmFeAsO and SmFeAsO0.86F0.14 although the later does not show any SDW transition. 19F hyperfine coupling constant found to be temperature independent.

  4. B-meson decays to eta' rho, eta' f0, and eta' K*

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Battaglia, M.; Brown, D.N.; Hooberman, B.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Tanabe, T.; /UC, Berkeley /Birmingham U. /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /INFN, Milan /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas U. /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2010-08-25

    We present measurements of B-meson decays to the final states {eta}{prime} {rho}, {eta}{prime} f{sub 0}, and {eta}{prime} K*, where K* stands for a vector, scalar, or tensor strange meson. We observe a significant signal or evidence for {eta}{prime} {rho}{sup +} and all the {eta}{prime}K* channels. We also measure, where applicable, the charge asymmetries, finding results consistent with no direct CP violation in all cases. The measurements are performed on a data sample consisting of 467 x 10{sup 6} B{bar B} pairs, collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. Our results favor the theoretical predictions from perturbative QCD and QCD Factorization and we observe an enhancement of the tensor K*{sub 2} (1430) with respect to the vector K*(892) component.

  5. Investigation of the interaction of copper(II) oxide and electron beam irradiation crosslinkable polyethylene

    NASA Astrophysics Data System (ADS)

    Bee, Soo-Tueen; Sin, Lee Tin; Ratnam, C. T.; Haraveen, K. J. S.; Tee, Tiam-Ting; Rahmat, A. R.

    2015-10-01

    In this study, the effects of electron beam irradiation on the properties of copper(II) oxide when added to low-density polyethylene (LDPE) blends were investigated. It was found that the addition of low loading level of copper(II) oxide (⩽2 phr) to LDPE results in significantly poorer gel content and hot set results. However, the incorporation of higher loading level of copper(II) oxide (⩾3 phr) could slightly increase the degree of crosslinking in all irradiated LDPE composites. This is due to the fact that higher amounts of copper(II) oxide could slightly induce the formation of free radicals in LDPE matrix. Besides, increasing irradiation doses was also found to gradually increase the gel content of LDPE composites by generating higher amounts of free radicals. As a consequence, these higher amounts of free radicals released in the LDPE matrix could significantly increase the degree of crosslinking. The addition of copper(II) oxide could reduce the tensile strength and fracture strain (elongation at break) of LDPE composites because of poorer interfacial adhesion effect between copper(II) oxide particles and LDPE matrix. Meanwhile, increasing irradiation doses on all copper(II) oxide added LDPE composites could marginally increase the tensile strength. In addition, increasing irradiation dose could enhance the thermal stability of LDPE composites by increasing the decomposition temperature. The oxidation induction time (OIT) analysis showed that, because of the crosslinking network in the copper(II) oxide added LDPE composites, oxidation reaction is much delayed.

  6. Suppression of superconductivity in Zn-doped SmFeAsO 0.8F 0.2 system

    NASA Astrophysics Data System (ADS)

    Cui, Y. J.; Chen, Y. L.; Cheng, C. H.; Yang, Y.; Zhao, Y.

    2011-11-01

    A series of SmFe1-xZnxAsO0.8F0.2 samples with x = 0, 0.05, 0.1, 0.2 and 0.4 have been successfully synthesized using a solid state method. The lattice parameters are found to increase with increasing Zn doping content. The superconductivity has been definitely suppressed by Zn doping at Fe site with the transition temperature Tc being reduced from 52.5 K to 23.3 K for the sample of x = 0.05, and to 18.2 K for the sample of x = 0.1. For the samples with x > 0.1, the superconducting transition vanishes, and, at the meantime, the spin-density-wave anomaly recovers at 140 K. The metal to semiconductor transition is also observed in the SmFe1-xZnxAsO0.8F0.2 system. The behavior of SmFe1-xZnxAsO0.8F0.2 is very different from that of REFeAsO (RE = rare earth metal), which reveals a very strong electron correlation in SmFe1-xZnxAsO0.8F0.2.

  7. The F0F1-ATP Synthase Complex Contains Novel Subunits and Is Essential for Procyclic Trypanosoma brucei

    PubMed Central

    Zíková, Alena; Schnaufer, Achim; Dalley, Rachel A.; Panigrahi, Aswini K.; Stuart, Kenneth D.

    2009-01-01

    The mitochondrial F0F1 ATP synthase is an essential multi-subunit protein complex in the vast majority of eukaryotes but little is known about its composition and role in Trypanosoma brucei, an early diverged eukaryotic pathogen. We purified the F0F1 ATP synthase by a combination of affinity purification, immunoprecipitation and blue-native gel electrophoresis and characterized its composition and function. We identified 22 proteins of which five are related to F1 subunits, three to F0 subunits, and 14 which have no obvious homology to proteins outside the kinetoplastids. RNAi silencing of expression of the F1 α subunit or either of the two novel proteins showed that they are each essential for the viability of procyclic (insect stage) cells and are important for the structural integrity of the F0F1-ATP synthase complex. We also observed a dramatic decrease in ATP production by oxidative phosphorylation after silencing expression of each of these proteins while substrate phosphorylation was not severely affected. Our procyclic T. brucei cells were sensitive to the ATP synthase inhibitor oligomycin even in the presence of glucose contrary to earlier reports. Hence, the two novel proteins appear essential for the structural organization of the functional complex and regulation of mitochondrial energy generation in these organisms is more complicated than previously thought. PMID:19436713

  8. $$B^{0}_{s}$$ Lifetime Measurement in the CP-odd Decay Channel $$B^{0}_{s} \\to J/\\psi\\mbox{ }f_{0}(980)$$

    DOE PAGES

    Abazov, V. M.

    2016-07-06

    Here, the lifetime of the Bs0 meson is measured in the decay channel Bs0→J/ψπ+π- with 880 ≤ Mπ+π- ≤ 1080 MeV/c2, which is mainly a CP-odd state and dominated by the f0(980) resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the Bs0 meson is measured to be τ(Bs0) = 1.70 ± 0.14(stat) ± 0.05(syst) ps. Neglecting CP violation in Bs0/more » $$\\bar{B}$$0s mixing, the measurement can be translated into the width of the heavy mass eigenstate of the Bs0, ΓH = 0.59 ± 0.05(stat) ± 0.02(syst) ps-1.« less

  9. Bs0 lifetime measurement in the C P -odd decay channel Bs0→J /ψ f 0(980 )

    NASA Astrophysics Data System (ADS)

    Abazov, V. M.; Abbott, B.; Acharya, B. S.; Adams, M.; Adams, T.; Agnew, J. P.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Askew, A.; Atkins, S.; Augsten, K.; Aushev, V.; Aushev, Y.; Avila, C.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Bartlett, J. F.; Bassler, U.; Bazterra, V.; Bean, A.; Begalli, M.; Bellantoni, L.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bhat, P. C.; Bhatia, S.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Boos, E. E.; Borissov, G.; Borysova, M.; Brandt, A.; Brandt, O.; Brochmann, M.; Brock, R.; Bross, A.; Brown, D.; Bu, X. B.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Buszello, C. P.; Camacho-Pérez, E.; Casey, B. C. K.; Castilla-Valdez, H.; Caughron, S.; Chakrabarti, S.; Chan, K. M.; Chandra, A.; Chapon, E.; Chen, G.; Cho, S. W.; Choi, S.; Choudhary, B.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Cuth, J.; Cutts, D.; Das, A.; Davies, G.; de Jong, S. J.; De La Cruz-Burelo, E.; Déliot, F.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Deterre, C.; DeVaughan, K.; Diehl, H. T.; Diesburg, M.; Ding, P. F.; Dominguez, A.; Dubey, A.; Dudko, L. V.; Duperrin, A.; Dutt, S.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Fauré, A.; Feng, L.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Franc, J.; Fuess, S.; Garbincius, P. H.; Garcia-Bellido, A.; García-González, J. A.; Gavrilov, V.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Gogota, O.; Golovanov, G.; Grannis, P. D.; Greder, S.; Greenlee, H.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guillemin, T.; Gutierrez, G.; Gutierrez, P.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Head, T.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-De La Cruz, I.; Hernández-Villanueva, M.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hogan, J.; Hohlfeld, M.; Holzbauer, J. L.; Howley, I.; Hubacek, Z.; Hynek, V.; Iashvili, I.; Ilchenko, Y.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jayasinghe, A.; Jeong, M. S.; Jesik, R.; Jiang, P.; Johns, K.; Johnson, E.; Johnson, M.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Jung, A. W.; Juste, A.; Kajfasz, E.; Karmanov, D.; Katsanos, I.; Kaur, M.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Kiselevich, I.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Lammers, S.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lei, X.; Lellouch, J.; Li, D.; Li, H.; Li, L.; Li, Q. Z.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, H.; Liu, Y.; Lobodenko, A.; Lokajicek, M.; Lopes de Sa, R.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Mansour, J.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Miconi, F.; Mondal, N. K.; Mulhearn, M.; Nagy, E.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nguyen, H. T.; Nunnemann, T.; Orduna, J.; Osman, N.; Pal, A.; Parashar, N.; Parihar, V.; Park, S. K.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, Y.; Petridis, K.; Petrillo, G.; Pétroff, P.; Pleier, M.-A.; Podstavkov, V. M.; Popov, A. V.; Prewitt, M.; Price, D.; Prokopenko, N.; Qian, J.; Quadt, A.; Quinn, B.; Ratoff, P. N.; Razumov, I.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Ross, A.; Royon, C.; Rubinov, P.; Ruchti, R.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Santos, A. S.; Savage, G.; Savitskyi, M.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schott, M.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shaw, S.; Shchukin, A. A.; Simak, V.; Skubic, P.; Slattery, P.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Soustruznik, K.; Stark, J.; Stefaniuk, N.; Stoyanova, D. A.; Strauss, M.; Suter, L.; Svoisky, P.; Titov, M.; Tokmenin, V. V.; Tsai, Y.-T.; Tsybychev, D.; Tuchming, B.; Tully, C.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; Van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verkheev, A. Y.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weichert, J.; Welty-Rieger, L.; Williams, M. R. J.; Wilson, G. W.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Yamada, R.; Yang, S.; Yasuda, T.; Yatsunenko, Y. A.; Ye, W.; Ye, Z.; Yin, H.; Yip, K.; Youn, S. W.; Yu, J. M.; Zennamo, J.; Zhao, T. G.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.; D0 Collaboration

    2016-07-01

    The lifetime of the Bs0 meson is measured in the decay channel Bs0→J /ψ π+π- with 880 ≤Mπ+π-≤1080 MeV /c2 , which is mainly a C P -odd state and dominated by the f0(980 ) resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the Bs0 meson is measured to be τ (Bs0)=1.70 ±0.14 (stat ) ±0.05 (syst) ps . Neglecting C P violation in Bs0/B¯s0 mixing, the measurement can be translated into the width of the heavy mass eigenstate of the Bs0, ΓH=0.59 ±0.05 (stat ) ±0.02 (syst ) ps-1 .

  10. New dinuclear copper(II) and zinc(II) complexes for the investigation of sugar-metal ion interactions.

    PubMed

    Bera, Manindranath; Patra, Ayan

    2011-10-18

    We have studied the binding interactions of biologically important carbohydrates (D-glucose, D-xylose and D-mannose) with the newly synthesized five-coordinate dinuclear copper(II) complex, [Cu(2)(hpnbpda)(μ-OAc)] (1) and zinc(II) complex, [Zn(2)(hpnbpda)(μ-OAc)] (2) [H(3)hpnbpda=N,N'-bis(2-pyridylmethyl)-2-hydroxy-1,3-propanediamine-N,N'-diacetic acid] in aqueous alkaline solution. The complexes 1 and 2 are fully characterized both in solid and solution using different analytical techniques. A geometrical optimization was made of the ligand H(3)hpnbpda and the complexes 1 and 2 by molecular mechanics (MM+) method in order to establish the stable conformations. All carbohydrates bind to the metal complexes in a 1:1 molar ratio. The binding events have been investigated by a combined approach of FTIR, UV-vis and (13)C NMR spectroscopic techniques. UV-vis spectra indicate a significant blue shift of the absorption maximum of complex 1 during carbohydrate coordination highlighting the sugar binding ability of complex 1. The apparent binding constants of the substrate-bound copper(II) complexes have been determined from the UV-vis titration experiments. The binding ability and mode of binding of these sugar substrates with complex 2 are indicated by their characteristic coordination induced shift (CIS) values in (13)C NMR spectra for carbon atoms C1, C2, and C3 of sugar substrates.

  11. Investigation of solution chemistry effects on sorption behavior of Cu(II) on ZSM-5 zeolite.

    PubMed

    Zhang, Lipeng; Zhang, Hui; Yu, Xianjin

    2011-12-01

    The sorption of Cu(II) from an aqueous solution using ZSM-5 zeolite was investigated by batch technique under ambient conditions. Sorption was investigated as a function of pH, ionic strength, foreign ions, humic substances, and temperature. The results indicate that the sorption of Cu(II) on ZSM-5 zeolite is strongly dependent on pH. Sorption is dependent on ionic strength at low pH, but independent of ionic strength at high pH values. The presence of humic/fluvic acid (HA/FA) enhances the sorption of Cu(II) on ZSM-5 zeolite at low pH values, and reduces Cu(II) sorption at high pH values. Sorption isotherms were well simulated by the Langmuir model. Thermodynamic parameters (i.e., deltaH0, deltaS0 and deltaG0) for the sorption of Cu(II) were determined from temperature-dependent sorption isotherms at 293.15, 313.15, and 333.15 K, respectively. Results indicate that the sorption process of Cu(II) on ZSM-5 zeolite is spontaneous and endothermic.

  12. Investigation on the efficiency and mechanism of Cd(II) and Pb(II) removal from aqueous solutions using MgO nanoparticles.

    PubMed

    Xiong, Chunmei; Wang, Wei; Tan, Fatang; Luo, Fan; Chen, Jianguo; Qiao, Xueliao

    2015-12-15

    In this study, the removal of Cd(II) and Pb(II) from aqueous solutions using MgO nanoparticles prepared by a simple sol-gel method was investigated. The efficiency of Cd(II) and Pb(II) removal was examined through batch adsorption experiments. For the single adsorption of Cd(II) and Pb(II), The adsorption kinetics and isotherm data obeyed well Pseudo-second-order and Langmuir models, indicating the monolayer chemisorption of heavy metal ions. The maximum adsorption capacities calculated by Langmuir equation were 2294 mg/g for Cd(II) and 2614 mg/g for Pb(II), respectively. The adsorption process was controlled simultaneously by external mass transfer and intraparticle diffusion. In the binary system, a competitive adsorption was observed, showing preference of adsorption followed Pb(II) >Cd(II). Significantly, the elution experiments confirmed that neither Cd(II) nor Pb(II) could be greatly desorbed after water washing even for five times. XRD and XPS measurements revealed the mechanism of Cd(II) and Pb(II) removal by MgO nanoparticles was mainly involved in precipitation and adsorption on the surface of MgO, resulting from the interaction between active sites of MgO and heavy metal ions. Easy preparation, remarkable removal efficiency and firmly adsorptive ability make the MgO nanoparticles to be an efficient material in the treatment of heavy metal-contaminated water.

  13. Experimental investigations of the influence of material and thickness on fracture under pure mode II loading

    NASA Astrophysics Data System (ADS)

    Dong, H.

    2010-06-01

    Experimental investigation to the effects of thickness and material on mode II fracture were performed. Tension-shear specimens made of aluminium alloy LC4CS and 7050-T7452 with thicknesses of 2, 4, 8 and 14 mm were used. All crack tip appearances and fracture profiles of the specimens were observed. Mode II fracture toughness were calculated. It is shown that material and thickness play an important role in mode II fracture. The fracture of LC4CS appears shear fracture under all kinds of thicknesses, however the fracture of 7050-T7452 is tensile fracture when thickness is larger or equal to 8mm, and shear initiation along the original crack plane, then turnaround and tensile failure when thickness is smaller than 8mm. Mode II fracture toughness is independent of thickness.

  14. Investigation of Cu(II) Binding to Bovine Serum Albumin by Potentiometry with an Ion Selective Electrode

    ERIC Educational Resources Information Center

    Jie Liu

    2004-01-01

    A laboratory project that investigates Cu(II) bind to bovine serum albumin (BSA) in an aqueous solution is developed to assist undergraduate students in gaining better understanding of the interaction of ligands with biological macromolecule. Thus, students are introduced to investigation of Cu(II) binding to BSA by potentiometry with the Cu(II)…

  15. Investigation of Cu(II) Binding to Bovine Serum Albumin by Potentiometry with an Ion Selective Electrode

    ERIC Educational Resources Information Center

    Jie Liu

    2004-01-01

    A laboratory project that investigates Cu(II) bind to bovine serum albumin (BSA) in an aqueous solution is developed to assist undergraduate students in gaining better understanding of the interaction of ligands with biological macromolecule. Thus, students are introduced to investigation of Cu(II) binding to BSA by potentiometry with the Cu(II)…

  16. Investigation of the column performance of cadmium(II) biosorption by Cladophora crispata flocs in a packed bed

    SciTech Connect

    Aksu, Z.; Kutsal, T.; Caglar, A.; Oezer, D.; Oezer, A.

    1998-03-01

    In this study the biosorption of cadmium(II) ions to dried flocs of Cladophora crispata, a kind of green algae, was investigated in a packed bed column. The cadmium(II) removal performance of the column was investigated as a function of the cadmium(II)-bearing solution flow rate and the inlet cadmium(II) concentration. Removal and total removal percentages of cadmium(II) related to flow volume were determined by evaluating the breakthrough curves obtained at three different flow rates for two different constant inlet concentrations. At the lowest flow rate the effect of inlet cadmium(II) concentration on the column capacity was also investigated. Data confirmed that early saturation and lower cadmium(II) removals were observed at higher flow rates and at higher cadmium(II) concentrations. Column experiments also showed that maximum specific cadmium(II) uptake values of C. crispata flocs were as high as those of other biomass sorbents.

  17. Physical property characterization of single step synthesized NdFeAsO0.80F0.20 bulk 50 K superconductor

    NASA Astrophysics Data System (ADS)

    Awana, V. P. S.; Meena, R. S.; Pal, A.; Vajpayee, A.; Rao, K. V. R.; Kishan, H.

    2011-01-01

    We report an easy single step synthesis route of title compound NdFeAsO0.80F0.20 superconductor having bulk superconductivity below 50 K. The title compound is synthesized via solid-state reaction route by encapsulation in an evacuated (10-3 Torr) quartz tube. Rietveld analysis of powder X-ray diffraction data shows that compound crystallized in tetragonal structure with space group P4/ nmm. R( T) H measurements showed superconductivity with T c ( R = 0) at 48 K and a very high upper critical field ( H c2) of up to 345 T. Magnetic measurements exhibited bulk superconductivity in terms of diamagnetic onset below 50 K. The lower critical field ( H c1) is around 1000 Oe at 5 K. In normal state i.e., above 60 K, the compound exhibited purely paramagnetic behavior and thus ruling out the presence of any ordered FeO x impurity in the matrix. In specific heat measurements a jump is observed in the vicinity of superconducting transition ( T c ) along with an upturn at below T = 4 K due to the AFM ordering of Nd+3 ions in the system. The Thermo-electric power (TEP) is negative down to T c , thus indicating dominant carriers to be of n-type in NdFeAsO0.80F0.20 superconductor. The granularity of the bulk superconducting NdFeAsO0.8F0.2 sample is investigated and the intra and inter grain contributions have been individuated by looking at various amplitude and frequencies of the applied AC drive magnetic field.

  18. F0 generation mice fully derived from gene-targeted embryonic stem cells allowing immediate phenotypic analyses.

    PubMed

    Poueymirou, William T; Auerbach, Wojtek; Frendewey, David; Hickey, Joseph F; Escaravage, Jennifer M; Esau, Lakeisha; Doré, Anthony T; Stevens, Sean; Adams, Niels C; Dominguez, Melissa G; Gale, Nicholas W; Yancopoulos, George D; DeChiara, Thomas M; Valenzuela, David M

    2007-01-01

    A useful approach for exploring gene function involves generating mutant mice from genetically modified embryonic stem (ES) cells. Recent advances in genetic engineering of ES cells have shifted the bottleneck in this process to the generation of mice. Conventional injections of ES cells into blastocyst hosts produce F0 generation chimeras that are only partially derived from ES cells, requiring additional breeding to obtain mutant mice that can be phenotyped. The tetraploid complementation approach directly yields mice that are almost entirely derived from ES cells, but it is inefficient, works only with certain hybrid ES cell lines and suffers from nonspecific lethality and abnormalities, complicating phenotypic analyses. Here we show that laser-assisted injection of either inbred or hybrid ES cells into eight cell-stage embryos efficiently yields F0 generation mice that are fully ES cell-derived and healthy, exhibit 100% germline transmission and allow immediate phenotypic analysis, greatly accelerating gene function assignment.

  19. Geomagnetic modification of the mid-latitude ionosphere - Toward a strategy for the improved forecasting of f0F2

    SciTech Connect

    Wrenn, G.L.; Rodger, A.S.

    1989-02-01

    An approach for modeling and forecasting the interspatial critical frequency (f0F2) at quiet and disturbed times is outlined. Statistical analyses of ionosonde data from the Argentine Islands (65 deg S) are used to define patterns for the main phase effects of midlatitude ionospheric storms. Extended to a number of stations, these could be incorporated into algorithms to permit the forecasting of maximum usable frequency for a few hours ahead and enhance the frequency management of shortwave radio communication, especially during a geomagnetic storm. Data from a complete solar cycle, 1971-1981, are used to determine the errors in the forecasts and to demonstrate that a useful advantage can be attained by this method. The rms error in f0F2 for 90,175 samples is 15.6 percent, which compares favorably with those obtained using forecasts based on quiet time values (20.4 percent) or the previous day's measurements (18 percent). 12 references.

  20. A multiwavelength investigation of the H II region S311: young stellar population and star formation

    NASA Astrophysics Data System (ADS)

    Yadav, Ram Kesh; Pandey, A. K.; Sharma, Saurabh; Ojha, D. K.; Samal, M. R.; Mallick, K. K.; Jose, J.; Ogura, K.; Richichi, Andrea; Irawati, Puji; Kobayashi, N.; Eswaraiah, C.

    2016-09-01

    We present a multiwavelength investigation of the young stellar population and star formation activities around the H II region Sharpless 311. Using our deep near-infrared observations and archival Spitzer-IRAC observations, we have detected a total of 125 young stellar objects (YSOs) in an area of ˜86 arcmin2. The YSO sample includes eight Class I and 117 Class II candidate YSOs. The mass completeness of the identified YSO sample is estimated to be 1.0 M⊙. The ages and masses of the majority of the candidate YSOs are estimated to be in the range ˜0.1-5 Myr and ˜0.3-6 M⊙, respectively. The 8-μm image of S311 displays an approximately spherical cavity around the ionizing source, which was possibly created by the expansion of the H II region. The spatial distribution of the candidate YSOs reveals that a significant number of them are distributed systematically along the 8-μm emission with a majority clustered around the eastern border of the H II region. Four clumps/compact H II regions are detected in the radio continuum observations at 1280 MHz, which may have been formed during the expansion of the H II region. The estimated dynamical age of the region, main-sequence lifetime of the ionizing source, the spatial distribution and ages of the candidate YSOs indicate triggered star formation in the complex.

  1. Measurements of the branching fraction and CP-violation asymmetries in B0-->f0(980)K0S.

    PubMed

    Aubert, B; Barate, R; Boutigny, D; Couderc, F; Gaillard, J-M; Hicheur, A; Karyotakis, Y; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Lynch, G; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, M T; Shelkov, V G; Wenzel, W A; Barrett, M; Ford, K E; Harrison, T J; Hart, A J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Cuhadar-Donszelmann, T; Hearty, C; Knecht, N S; Mattison, T S; McKenna, J A; Thiessen, D; Khan, A; Kyberd, P; Teodorescu, L; Blinov, V E; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M; Mommsen, R K; Roethel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Foulkes, S D; Gary, J W; Shen, B C; Wang, K; del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, Sh; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, J; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q L; Altenburg, D; Brandt, T; Brose, J; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, K R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, Ch; Vasileiadis, G; Verderi, M; Bard, D J; Clark, P J; Lavin, D; Muheim, F; Playfer, S; Xie, Y; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; de Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Charles, M J; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Chavez, C A; Coleman, J P; Forster, I J; Fry, J R; Gabathuler, E; Gamet, R; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Cormack, C M; Harrison, P F; Di Lodovico, F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flaecher, H U; Green, M G; Jackson, P S; McMahon, T R; Ricciardi, S; Salvatore, F; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Staengle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonyan, R; Wong, Q K; Brau, J; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; de la Vaissière, Ch; Del Buono, L; Hamon, O; John, M J J; Leruste, Ph; Malcles, J; Ocariz, J; Pivk, M; Roos, L; T'Jampens, S; Therin, G; Manfredi, P F; Re, V; Behera, P K; Gladney, L; Guo, Q H; Panetta, J; Anulli, F; Biasini, M; Peruzzi, I M; Pioppi, M; Angelini, C; Batignani, G; Bettarini, S; Bondioli, M; Bucci, F; Calderini, G; Carpinelli, M; Del Gamba, V; Forti, F; Giorgi, M A; Lusiani, A; Marchiori, G; Martinez-Vidal, F; Morganti, M; Neri, N; Paoloni, E; Rama, M; Rizzo, G; Sandrelli, F; Walsh, J; Haire, M; Judd, D; Paick, K; Wagoner, D E; Danielson, N; Elmer, P; Lau, Y P; Lu, C; Miftakov, V; Olsen, J; Smith, A J S; Telnov, A V; Bellini, F; Cavoto, G; Faccini, R; Ferrarotto, F; Ferroni, F; Gaspero, M; Li Gioi, L; Mazzoni, M A; Morganti, S; Pierini, M; Piredda, G; Safai Tehrani, F; Voena, C; Christ, S; Wagner, G; Waldi, R; Adye, T; De Groot, N; Franek, B; Geddes, N I; Gopal, G P; Olaiya, E O; Aleksan, R; Emery, S; Gaidot, A; Ganzhur, S F; Giraud, P-F; Hamel de Monchenault, G; Kozanecki, W; Langer, M; Legendre, M; London, G W; Mayer, B; Schott, G; Vasseur, G; Yèche, Ch; Zito, M; Purohit, M V; Weidemann, A W; Wilson, J R; Yumiceva, F X; Aston, D; Bartoldus, R; Berger, N; Boyarski, A M; Buchmueller, O L; Convery, M R; Cristinziani, M; De Nardo, G; Dong, D; Dorfan, J; Dujmic, D; Dunwoodie, W; Elsen, E E; Fan, S; Field, R C; Glanzman, T; Gowdy, S J; Hadig, T; Halyo, V; Hast, C; Hryn'ova, T; Innes, W R; Kelsey, M H; Kim, P; Kocian, M L; Leith, D W G S; Libby, J; Luitz, S; Luth, V; Lynch, H L; Marsiske, H; Messner, R; Muller, D R; O'Grady, C P; Ozcan, V E; Perazzo, A; Perl, M; Petrak, S; Ratcliff, B N; Roodman, A; Salnikov, A A; Schindler, R H; Schwiening, J; Simi, G; Snyder, A; Soha, A; Stelzer, J; Su, D; Sullivan, M K; Va'vra, J; Wagner, S R; Weaver, M; Weinstein, A J R; Wisniewski, W J; Wittgen, M; Wright, D H; Yarritu, A K; Young, C C; Burchat, P R; Edwards, A J; Meyer, T I; Petersen, B A; Roat, C; Ahmed, S; Alam, M S; Ernst, J A; Saeed, M A; Saleem, M; Wappler, F R; Bugg, W; Krishnamurthy, M; Spanier, S M; Eckmann, R; Kim, H; Ritchie, J L; Satpathy, A; Schwitters, R F; Izen, J M; Kitayama, I; Lou, X C; Ye, S; Bianchi, F; Bona, M; Gallo, F; Gamba, D; Borean, C; Bosisio, L; Cartaro, C; Cossutti, F; Della Ricca, G; Dittongo, S; Grancagnolo, S; Lanceri, L; Poropat, P; Vitale, L; Vuagnin, G; Panvini, R S; Banerjee, Sw; Brown, C M; Fortin, D; Jackson, P D; Kowalewski, R; Roney, J M; Band, H R; Dasu, S; Datta, M; Eichenbaum, A M; Graham, M; Hollar, J J; Johnson, J R; Kutter, P E; Li, H; Liu, R; Mihalyi, A; Mohapatra, A K; Pan, Y; Prepost, R; Rubin, A E; Sekula, S J; Tan, P; von Wimmersperg-Toeller, J H; Wu, J; Wu, S L; Yu, Z; Greene, M G; Neal, H

    2005-02-04

    We present measurements of the branching fraction and CP-violating asymmetries in the decay B0-->f0(980)K0S. The results are obtained from a data sample of 123 x 10(6) Upsilon(4S)-->BB decays. From a time-dependent maximum likelihood fit, we measure the branching fraction B(B0-->f0(980)(-->pi+pi-)K0)=(6.0+/-0.9+/-0.6+/-1.2)x10(-6), the mixing-induced CP violation parameter S=-1.62(+0.56)(-0.51)+/-0.09+/-0.04, and the direct CP violation parameter C=0.27+/-0.36+/-0.10+/-0.07, where the first errors are statistical, the second systematic, and the third due to model uncertainties. We measure the f0(980) mass and width to be mf0(980)=(980.6+/-4.1+/-0.5+/-4.0) MeV/c2 and Gammaf0(980)=(43(+12)(-9)+/-3+/-9) MeV/c2, respectively.

  2. Evidence from immunological studies of structure-mechanism relationship of F1 and F1F0.

    PubMed

    Gautheron, D C; Godinot, C

    1988-08-01

    Monoclonal and polyclonal antibodies directed against peptides of F1-ATPase of F1F0-ATPase synthase provide new and efficient tools to study structure-function relationships and mechanisms of such complex membrane enzymes. This review summarizes the main results obtained using this approach. Antibodies have permitted the determination of the nature of subunits involved in the complex, their stoichiometry, their organization, neighboring interactions, and vectorial distribution within or on either face of the membrane. Moreover, in a few cases, amino acid sequences exposed on a face of the membrane or buried inside the complex have been identified. Antibodies are very useful for detecting the role of each subunit, especially for those subunits which appear to have no direct involvement in the catalytic mechanism. Concerning the mechanisms, the availability of monoclonal antibodies which inhibit (or activate) ATP hydrolysis or ATP synthesis, which modify nucleotide binding or regulation of activities, which detect specific conformations, etc. brings many new ways of understanding the precise functions. The specific recognition by monoclonal antibodies on the beta subunit of epitopes in the proximity of, or in the catalytic site, gives information on this site. The use of anti-alpha monoclonal antibodies has shown asymmetry of alpha in the complex as already shown for beta. In addition, the involvement of alpha with respect to nucleotide site cooperativity has been detected. Finally, the formation of F1F0-antibody complexes of various masses, seems to exclude the functional rotation of F1 around F0 during catalysis.

  3. Binding of Co(II) and Cu(II) cations to chemically modified wool fibres: an IR investigation

    NASA Astrophysics Data System (ADS)

    Taddei, Paola; Monti, Patrizia; Freddi, Giuliano; Arai, Takayuki; Tsukada, Masuhiro

    2003-05-01

    Wool fibres were modified by treatment with tannic acid (TA) solution or by acylation with ethylenediaminetetraacetic (EDTA) dianhydride. The unmodified and modified fibres were subsequently treated with Cu 2+ and Co 2+ solutions, at alkaline pH, and analysed by Attenuated Total Reflectance, ATR/IR spectroscopy to evaluate the changes induced in the structure of the fibre by metal binding. The spectral changes were correlated to metal adsorption results obtained by Inductive Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The IR results were discussed in relation to our previous findings on the metal binding mode of Bombyx mori and Tussah silk fibres; the changes observed in the spectra were explained by considering the different affinity of the fibres for the modifying reagent and the amount of the metal absorbed. More relevant spectral changes were observed upon Cu 2+ complexation rather than Co 2+ complexation, according to the metal absorption results. The most relevant changes were observed for the EDTA-modified wool sample treated with Cu 2+, according to the higher affinity of wool for EDTA. The IR spectra were quantitatively evaluated by the intensity ratio between the Amide I and Amide II bands (I AmideI/I AmideII) and its trend as a function of metal absorption was reported. The present investigation demonstrated that the interaction between fibre and metal and the subsequent fibre modification depend on the chemical nature of the fibre, the metal cation and the modifying reagent.

  4. Diagnostic pathways in acute pulmonary embolism: recommendations of the PIOPED II investigators.

    PubMed

    Stein, Paul D; Woodard, Pamela K; Weg, John G; Wakefield, Thomas W; Tapson, Victor F; Sostman, H Dirk; Sos, Thomas A; Quinn, Deborah A; Leeper, Kenneth V; Hull, Russell D; Hales, Charles A; Gottschalk, Alexander; Goodman, Lawrence R; Fowler, Sarah E; Buckley, John D

    2006-12-01

    To formulate comprehensive recommendations for the diagnostic approach to patients with suspected pulmonary embolism, based on randomized trials. Diagnostic management recommendations were formulated based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II) and outcome studies. The PIOPED II investigators recommend stratification of all patients with suspected pulmonary embolism according to an objective clinical probability assessment. D-dimer should be measured by the quantitative rapid enzyme-linked immunosorbent assay (ELISA), and the combination of a negative D-dimer with a low or moderate clinical probability can safely exclude pulmonary embolism in many patients. If pulmonary embolism is not excluded, contrast-enhanced computed tomographic pulmonary angiography (CT angiography) in combination with venous phase imaging (CT venography), is recommended by most PIOPED II investigators, although CT angiography plus clinical assessment is an option. In pregnant women, ventilation/perfusion scans are recommended by many as the first imaging test following D-dimer and perhaps venous ultrasound. In patients with discordant findings of clinical assessment and CT angiograms or CT angiogram/CT venogram, further evaluation may be necessary. The sequence for diagnostic test in patients with suspected pulmonary embolism depends on the clinical circumstances.

  5. Adherence to PIOPED II investigators' recommendations for computed tomography pulmonary angiography.

    PubMed

    Adams, Daniel M; Stevens, Scott M; Woller, Scott C; Evans, R Scott; Lloyd, James F; Snow, Gregory L; Allen, Todd L; Bledsoe, Joseph R; Brown, Lynette M; Blagev, Denitza P; Lovelace, Todd D; Shill, Talmage L; Conner, Karen E; Aston, Valerie T; Elliott, C Gregory

    2013-01-01

    Computed tomography (CT) pulmonary angiography use has increased dramatically, raising concerns for patient safety. Adherence to recommendations and guidelines may protect patients. We measured adherence to the recommendations of Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED II) investigators for evaluation of suspected pulmonary embolism and the rate of potential false-positive pulmonary embolism diagnoses when recommendations of PIOPED II investigators were not followed. We used a structured record review to identify 3500 consecutive CT pulmonary angiograms performed to investigate suspected pulmonary embolism in 2 urban emergency departments, calculating the revised Geneva score (RGS) to classify patients as "pulmonary embolism unlikely" (RGS≤10) or "pulmonary embolism likely" (RGS>10). CT pulmonary angiograms were concordant with PIOPED II investigator recommendations if pulmonary embolism was likely or pulmonary embolism was unlikely and a highly sensitive D-dimer test result was positive. We independently reviewed 482 CT pulmonary angiograms to measure the rate of potential false-positive pulmonary embolism diagnoses. A total of 1592 of 3500 CT pulmonary angiograms (45.5%) followed the recommendations of PIOPED II investigators. The remaining 1908 CT pulmonary angiograms were performed on patients with an RGS≤10 without a D-dimer test (n=1588) or after a negative D-dimer test result (n=320). The overall rate of pulmonary embolism was 9.7%. Potential false-positive diagnoses of pulmonary embolism occurred in 2 of 3 patients with an RGS≤10 and a negative D-dimer test result. Nonadherence to recommendations for CT pulmonary angiography is common and exposes patients to increased risks, including potential false-positive diagnoses of pulmonary embolism. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Investigation of the exciton emission lifetime in type-II spherical core/shell semiconductor heteronanostructures

    NASA Astrophysics Data System (ADS)

    Arfaoui, A.; Mahdouani, M.; Bourguiga, R.

    2017-08-01

    The two-band model effective mass approximation has been adopted to explain the energy spectra in type-I CdSe core-only and type-II CdSe/CdTe core/shell quantum dots (QDs). As optical properties, the emission wavelength, the electron-hole overlap integral and the radiative recombination lifetime have been investigated. The simulated emission spectra are in good agreement with available experimental results for both core-only and core/shell QDs. The radiative recombination lifetime (τrad) has been investigated in different carrier localization regimes and compared to that corresponding to core-only QDs. We have found a sudden increase in τrad at around r1 1.1 nm suggesting the transition of the heterostructure from the quasi-type-II to the type-II regime. A monotonic increase in τrad with the core and shell sizes (geometric parameters) was observed. Also found is the possibility of increasing τrad over two orders of magnitude with a suitable change in the geometric parameters. The long radiative lifetime produced by increasing the geometric parameters is found due to spatial separation of the carriers, which makes the type-II core/shell QDs made from large core and shell sizes promising for photovoltaic applications.

  7. Melanoma-targeted delivery system (part 2): Synthesis, radioiodination and biological evaluation in B16F0 bearing mice.

    PubMed

    El Aissi, Radhia; Miladi, Imen; Chezal, Jean-Michel; Chavignon, Olivier; Miot-Noirault, Elisabeth; Moreau, Emmanuel

    2016-09-14

    Here we report the synthesis and radiolabelling with iodine-125 of a melanoma-selective prodrug (17a*) and its parent drug IUdR. The in vivo and ex vivo biodistributions of [(125)I](17a*) and [(125)I]IUdR were evaluated in a model of melanoma B16F0-bearing mice. The pharmacokinetic profile of [(125)I](17a*) suggests rapid release of the active drug [(125)I]IUdR after i.v. administration of [(125)I](17a*). Preliminary metabolism studies in dedicated compartments (i.e. blood, urine and tumour) yielded results consistent with this hypothesis.

  8. The membrane-associated F(0)F(1) ATPase is essential for the viability of Streptococcus pneumoniae.

    PubMed

    Ferrándiz, María José; de la Campa, Adela G

    2002-06-18

    Genetic studies aimed at eliminating expression of the atp operon (F(0)F(1) H(+)-ATPase) of Streptococcus pneumoniae by genetic disruption of atpC, the first gene of the operon, with a chloramphenicol-resistance cassette were performed. Resistant transformants were obtained only when the recipient strain had a duplication of atpC, recombination occurring in such a way that transcription of the operon from its own promoter was allowed. These results imply that the atp operon is essential for the viability of the cells.

  9. High-efficiency non-mosaic CRISPR-mediated knock-in and indel mutation in F0 Xenopus.

    PubMed

    Aslan, Yetki; Tadjuidje, Emmanuel; Zorn, Aaron M; Cha, Sang-Wook

    2017-08-01

    The revolution in CRISPR-mediated genome editing has enabled the mutation and insertion of virtually any DNA sequence, particularly in cell culture where selection can be used to recover relatively rare homologous recombination events. The efficient use of this technology in animal models still presents a number of challenges, including the time to establish mutant lines, mosaic gene editing in founder animals, and low homologous recombination rates. Here we report a method for CRISPR-mediated genome editing in Xenopus oocytes with homology-directed repair (HDR) that provides efficient non-mosaic targeted insertion of small DNA fragments (40-50 nucleotides) in 4.4-25.7% of F0 tadpoles, with germline transmission. For both CRISPR/Cas9-mediated HDR gene editing and indel mutation, the gene-edited F0 embryos are uniformly heterozygous, consistent with a mutation in only the maternal genome. In addition to efficient tagging of proteins in vivo, this HDR methodology will allow researchers to create patient-specific mutations for human disease modeling in Xenopus. © 2017. Published by The Company of Biologists Ltd.

  10. a1(1420 ) peak as the π f0(980 ) decay mode of the a1(1260 )

    NASA Astrophysics Data System (ADS)

    Aceti, F.; Dai, L. R.; Oset, E.

    2016-11-01

    We study the decay mode of the a1(1260 ) into a π+ in p wave and the f0(980 ) that decays into π+π- in s wave. The mechanism proceeds via a triangular mechanism where the a1(1260 ) decays into K*K ¯, the K* decays to an external π+ and an internal K that fuses with the K ¯ producing the f0(980 ) resonance. The mechanism develops a singularity at a mass of the a1(1260 ) around 1420 MeV, producing a peak in the cross section of the π p reaction, used to generate the mesonic final state, which provides a natural explanation of all the features observed in the COMPASS experiment, where a peak observed at this energy is tentatively associated to a new resonance called a1(1420 ). On the other hand, the triangular singularity studied here gives rise to a remarkable feature, where a peak is seen for a certain decay channel of a resonance at an energy about 200 MeV higher than its nominal mass.

  11. F1F0 ATP Synthase-Cyclophilin D Interaction Contributes to Diabetes-Induced Synaptic Dysfunction and Cognitive Decline.

    PubMed

    Yan, Shijun; Du, Fang; Wu, Long; Zhang, Zhihua; Zhong, Changjia; Yu, Qing; Wang, Yongfu; Lue, Lih-Fen; Walker, Douglas G; Douglas, Justin T; Yan, Shirley ShiDu

    2016-11-01

    Mitochondrial abnormalities are well known to cause cognitive decline. However, the underlying molecular basis of mitochondria-associated neuronal and synaptic dysfunction in the diabetic brain remains unclear. Here, using a mitochondrial single-channel patch clamp and cyclophilin D (CypD)-deficient mice (Ppif (-/-)) with streptozotocin-induced diabetes, we observed an increase in the probability of Ca(2+)-induced mitochondrial permeability transition pore (mPTP) opening in brain mitochondria of diabetic mice, which was further confirmed by mitochondrial swelling and cytochrome c release induced by Ca(2+) overload. Diabetes-induced elevation of CypD triggers enhancement of F1F0 ATP synthase-CypD interaction, which in turn leads to mPTP opening. Indeed, in patients with diabetes, brain cypD protein levels were increased. Notably, blockade of the F1F0 ATP synthase-CypD interaction by CypD ablation protected against diabetes-induced mPTP opening, ATP synthesis deficits, oxidative stress, and mitochondria dysfunction. Furthermore, the absence of CypD alleviated deficits in synaptic plasticity, learning, and memory in diabetic mice. Thus, blockade of ATP synthase interaction with CypD provides a promising new target for therapeutic intervention in diabetic encephalopathy. © 2016 by the American Diabetes Association.

  12. Realistic simulations of the coupling between the protomotive force and the mechanical rotation of the F0-ATPase

    PubMed Central

    Mukherjee, Shayantani; Warshel, Arieh

    2012-01-01

    The molecular origin of the action of the F0 proton gradient-driven rotor presents a major puzzle despite significant structural advances. Although important conceptual models have provided guidelines of how such systems should work, it has been challenging to generate a structure-based molecular model using physical principles that will consistently lead to the unidirectional proton-driven rotational motion during ATP synthesis. This work uses a coarse-grained (CG) model to simulate the energetics of the F0-ATPase system in the combined space defined by the rotational coordinate and the proton transport (PTR) from the periplasmic side (P) to the cytoplasmic side (N). The model establishes the molecular origin of the rotation, showing that this effect is due to asymmetry in the energetics of the proton path rather than only the asymmetry of the interaction of the Asp on the c-ring helices and Arg on the subunit-a. The simulation provides a clear conceptual background for further exploration of the electrostatic basis of proton-driven mechanochemical systems. PMID:22927379

  13. Fundamental properties of Fanaroff-Riley type II radio galaxies investigated via Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Kapińska, A. D.; Uttley, P.; Kaiser, C. R.

    2012-08-01

    Radio galaxies and quasars are among the largest and most powerful single objects known and are believed to have had a significant impact on the evolving Universe and its large-scale structure. We explore the intrinsic and extrinsic properties of the population of Fanaroff-Riley type II (FR II) objects, i.e. their kinetic luminosities, lifetimes and the central densities of their environments. In particular, the radio and kinetic luminosity functions of these powerful radio sources are investigated using the complete, flux-limited radio catalogues of the Third Cambridge Revised Revised Catalogue (3CRR) and Best et al. We construct multidimensional Monte Carlo simulations using semi-analytical models of FR II source time evolution to create artificial samples of radio galaxies. Unlike previous studies, we compare radio luminosity functions found with both the observed and simulated data to explore the best-fitting fundamental source parameters. The new Monte Carlo method we present here allows us to (i) set better limits on the predicted fundamental parameters of which confidence intervals estimated over broad ranges are presented and (ii) generate the most plausible underlying parent populations of these radio sources. Moreover, as has not been done before, we allow the source physical properties (kinetic luminosities, lifetimes and central densities) to co-evolve with redshift, and we find that all the investigated parameters most likely undergo cosmological evolution. Strikingly, we find that the break in the kinetic luminosity function must undergo redshift evolution of at least (1 + z)3. The fundamental parameters are strongly degenerate, and independent constraints are necessary to draw more precise conclusions. We use the estimated kinetic luminosity functions to set constraints on the duty cycles of these powerful radio sources. A comparison of the duty cycles of powerful FR IIs with those determined from radiative luminosities of active galactic nuclei of

  14. Investigation of high velocity separator for particle removal in coal gasification plants. Phase II report

    SciTech Connect

    Linhardt, H.D.

    1980-01-15

    This report summarizes the results of Phase II of the High Velocity Particle Separator Program performed under Contract EF-77-C-01-2709. This high velocity wedge separator has the potential to reduce equipment size and cost of high temperature and pressurized particulate removal equipment for coal derived gases. Phase II has been directed toward testing and detailed conceptual design of an element suitable for a commercial scale high temperature, high pressure particle separator (HTPS). Concurrently, Phase IA has been conducted, which utilized the ambient analog method (AAM) for aerodynamic and collection performance investigation of each HTPS configuration prior and during hot testing. This report summarizes the results of Phase IA and II. The AAM effort established correlation of theoretical analysis and experiment for HTPS pressure drop, purge flow ratio and collection efficiency potential. Task I defined the initial test conditions to be the contract design point of 1800/sup 0/F and 350 psia. The 1800/sup 0/F, 350 psia testing represents the main high temperature testing with coal-derived particulates in the 2 to 10 micron range. Phase IA and Phase II have demonstrated efficient particle collection with acceptable pressure drop. In view of these encouraging results, it is reasonable to apply the developed technology toward future hot gas particulate cleanup requirements.

  15. Investigation of Mesoporous Graphitic Carbon Nitride as the Adsorbent to Remove Ni (II) Ions.

    PubMed

    Xin, Gang; Xia, Yuanjiao; Lv, Yuhua; Liu, Luman; Yu, Bei

    2016-04-01

    The mesoporous graphitic carbon nitride (mpg-C3N4/r, r was defined as the initial silica/dicyandiamide mass ratio) was successfully synthesized by heating the mixture of silica and dicyandiamide in a nitrogen atmosphere. The morphology and structure of mpg-C3N4/r were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller surface area measurement (BET), X-ray powder diffraction (XRD), and Fourier Transform Infrared spectroscopy (FT-IR). The adsorption performances of Ni (II) ions by mpg-C3N4/r were investigated. With increasing of r value, the BET specific surface area of the synthesized mpg-C3N4/r increased; the highest specific surface area of mpg-C3N4/1.5 increased up to 169.3 m2/g. This work shows that mpg-C3N4/1.5 is a promising, high-efficiency adsorbent that can be used to purify the water of a low Ni (II) ions concentration. The maximum adsorption capacity of Ni(II) ions by mpg-C3N4/1.5 was 15.26 mg/g. The adsorption properties of Ni (II) ions by mpg-C3N4/r complied well with pseudo-second-order kinetics and Langmuir isotherm model.

  16. SPM-Based Investigations of Molecular Events Sparked by Ang II

    NASA Astrophysics Data System (ADS)

    Goolsby, Brandy; Gilgenbach, Karen; Saglik, Harun; Hummert, Henning; Salam, Fathi; Xi, Ning; Wang, Donna; Ayres, Virginia

    2001-03-01

    We will present our recent research on the development and use of a precision robotic scanning probe microscope system for nanomanipulation and site-specific probing of biological specimens. We propose to use cellular and molecular events triggered by angiotensin II, one of the most powerful factors involved in blood pressure regulation, as a model scheme for the development of the scanning probe microscope (SPM) robotic system. The central hypothesis that will be tested is that cellular and molecular events triggered by angiotensin II differ in a segment-specific manner based on particular components expressed in each of the segments in the renal nephron, resulting in distinct functionality of angiotensin II in these segments. Novel sensor-based intelligent processing and control schemes will be incorporated within the SPM robotic system to achieve reliable and precise manipulations to enable the first direct investigations of angiotensin II receptor sub-type function and coupled signaling pathways in different segments of the renal nephron. The research seeks to understand and exploit the interaction forces between the nano

  17. MX Siting Investigation. Mineral Resources Survey, Seven Additional Valleys, Nevada/Utah Siting Area. Volume II.

    DTIC Science & Technology

    1981-06-23

    AO-AI13 14𔃾 ERTEC WESTERN INC LONG BEACH CA F/6 7/4 MX SITING INVESTIGATION. MINERAL RESOURCES SURVEY, SEVEN ADDITI-ETC(U) JUN Al F04704-80-C-OGO6...DTIC-DDA-2 FORM DOCUMENT PROCESSING SHEET DTIC ocT :g 70A -- ~’ .9 ’I K ii I / "~1 - i~ / . . ..1’ ~ ~- .. ~ ~1 I E-TR-50 MINERAL RESOURCES SURVEY...144 ERTEC WESTERN INC. LONG BEACH CA F/6 7/4 MX SITING INVESTIGATION. MINERAL RESOURCES SURVEY. SEVEN AOOITI-ETCIU) JUN 81 FON7O-80-C-0006

  18. Investigation of Propellant and Explosive Solid Solution Systems II X-Ray Studies

    DTIC Science & Technology

    1978-03-01

    A\\Yj* ^\\C/*^ ^ 1 tatf AD 7t ott w AD-E400 125 TECHNICAL REPORT ARLCD-TR-77066 INVESTIGATION OF PROPELLANT AND EXPLOSIVE SOLID SOLUTION SYSTEMS...Report ARLCD-TR-77066 2. GOVT ACCESSION NO. *. TITLE (and Subtitle) INVESTIGATION OF PROPELLANT AND EXPLOSIVE SOLID SOLUTION SYSTEMS II X-RAY...Interplanar spacings and x-ray diffraction 9 intensities of AP, KP and their physical mixtures and solid solutions 4 X-ray data of 3 AN: KP solid solution and

  19. Goethite surface reactivity: a macroscopic investigation unifying proton, chromate, carbonate, and lead(II) adsorption.

    PubMed

    Villalobos, Mario; Pérez-Gallegos, Ayax

    2008-10-15

    The goethite surface structure has been extensively studied, but no convincing quantitative description of its highly variable surface reactivity as inversely related to its specific surface area (SSA) has been found. The present study adds experimental evidence and provides a unified macroscopic explanation to this anomalous behavior from differences in average adsorption capacities, and not in average adsorption affinities. We investigated the chromate anion and lead(II) cation adsorption behavior onto three different goethites with SSA varying from 50 to 94 m(2)/g, and analyzed an extensive set of published anion adsorption and proton charging data for variable SSA goethites. Maximum chromate adsorption was found to occupy on average from 3.1 to 9.7 sites/nm(2), inversely related to SSA. Congruency of oxyanion and Pb(II) adsorption behavior based on fractional site occupancy using these values, and a site density analysis suggest that: (i) ion binding occurs to singly and doubly coordinated sites, (ii) proton binding occurs to singly and triply coordinated sites (ranging from 6.2 to 8 total sites/nm(2), in most cases), and (iii) a predominance of (210) and/or (010) faces explains the high reactivity of low SSA goethites. The results imply that the macroscopic goethite adsorption behavior may be predicted without a need to investigate extensive structural details of each specific goethite of interest.

  20. Investigational drug tracking: phases I-III and NDA submissions--Part II.

    PubMed

    Grant, K L

    1994-10-01

    The author catalogs over 800 investigational drugs/biologicals currently in Phase I, II or III clinical trials or drugs/biologicals submitted to the FDA as new drug applications. Part I of this article appeared in the September issue of Hospital Pharmacy. The list assists in predicting when new drugs will be marketed. The entries include generic/chemical name, investigational drug number, synonyms, trade names, manufacturers, clinical trial status, predicted approval year, indications or drug class, whether the drug has been developed through biotechnology, and references. Entries were gleaned from medical journals, stock market analysis publications, and the Pharmaceutical Manufacturers Association's Medicines in Development Series. The list is alphabetized by the generic/chemical name or investigational drug number and cross-indexed by the trade name and synonyms. The list reflects those drugs which were not FDA approved as of April 15, 1994. Part I concludes with the remaining alphabetical listing by generic/chemical name or investigational drug number.

  1. Investigation of the polarization state of dual APPLE-II undulators

    PubMed Central

    Hand, Matthew; Wang, Hongchang; Dhesi, Sarnjeet S.; Sawhney, Kawal

    2016-01-01

    The use of an APPLE II undulator is extremely important for providing a high-brilliance X-ray beam with the capability to switch between various photon beam polarization states. A high-precision soft X-ray polarimeter has been used to systematically investigate the polarization characteristics of the two helical APPLE II undulators installed on beamline I06 at Diamond Light Source. A simple data acquisition and processing procedure has been developed to determine the Stokes polarization parameters for light polarized at arbitrary linear angles emitted from a single undulator, and for circularly polarized light emitted from both undulators in conjunction with a single-period undulator phasing unit. The purity of linear polarization is found to deteriorate as the polarization angle moves away from the horizontal and vertical modes. Importantly, a negative correlation between the degree of circular polarization and the photon flux has been found when the phasing unit is used. PMID:26698061

  2. Investigation of the polarization state of dual APPLE-II undulators.

    PubMed

    Hand, Matthew; Wang, Hongchang; Dhesi, Sarnjeet S; Sawhney, Kawal

    2016-01-01

    The use of an APPLE II undulator is extremely important for providing a high-brilliance X-ray beam with the capability to switch between various photon beam polarization states. A high-precision soft X-ray polarimeter has been used to systematically investigate the polarization characteristics of the two helical APPLE II undulators installed on beamline I06 at Diamond Light Source. A simple data acquisition and processing procedure has been developed to determine the Stokes polarization parameters for light polarized at arbitrary linear angles emitted from a single undulator, and for circularly polarized light emitted from both undulators in conjunction with a single-period undulator phasing unit. The purity of linear polarization is found to deteriorate as the polarization angle moves away from the horizontal and vertical modes. Importantly, a negative correlation between the degree of circular polarization and the photon flux has been found when the phasing unit is used.

  3. A simple, inexpensive implementation of the F0 concept of autoclave cycle validation using a portable data logger with a remote microcomputer.

    PubMed

    Bell, D; Farrell, P S; Small, D C

    1987-06-01

    This paper describes the conversion of an autoclave, previously controlled by a bottle simulator and monitored using MTRs, to one controlled by a bottle probe and monitored using F0 values. Temperatures were recorded with a portable data logger and a micro-computer was used to calculate F0 values and produce batch reports.

  4. Measurement of the B¯(s)(0) effective lifetime in the J/ψf0(980) final state.

    PubMed

    Aaij, R; Abellan Beteta, C; Adametz, A; Adeva, B; Adinolfi, M; Adrover, C; Affolder, A; Ajaltouni, Z; Albrecht, J; Alessio, F; Alexander, M; Ali, S; Alkhazov, G; Alvarez Cartelle, P; Alves, A A; Amato, S; Amhis, Y; Anderlini, L; Anderson, J; Appleby, R B; Aquines Gutierrez, O; Archilli, F; Artamonov, A; Artuso, M; Aslanides, E; Auriemma, G; Bachmann, S; Back, J J; Balagura, V; Baldini, W; Barlow, R J; Barschel, C; Barsuk, S; Barter, W; Bates, A; Bauer, C; Bauer, Th; Bay, A; Beddow, J; Bediaga, I; Belogurov, S; Belous, K; Belyaev, I; Ben-Haim, E; Benayoun, M; Bencivenni, G; Benson, S; Benton, J; Bernet, R; Bettler, M-O; van Beuzekom, M; Bien, A; Bifani, S; Bird, T; Bizzeti, A; Bjørnstad, P M; Blake, T; Blanc, F; Blanks, C; Blouw, J; Blusk, S; Bobrov, A; Bocci, V; Bondar, A; Bondar, N; Bonivento, W; Borghi, S; Borgia, A; Bowcock, T J V; Bozzi, C; Brambach, T; van den Brand, J; Bressieux, J; Brett, D; Britsch, M; Britton, T; Brook, N H; Brown, H; Büchler-Germann, A; Burducea, I; Bursche, A; Buytaert, J; Cadeddu, S; Callot, O; Calvi, M; Calvo Gomez, M; Camboni, A; Campana, P; Carbone, A; Carboni, G; Cardinale, R; Cardini, A; Carson, L; Carvalho Akiba, K; Casse, G; Cattaneo, M; Cauet, Ch; Charles, M; Charpentier, Ph; Chen, P; Chiapolini, N; Chrzaszcz, M; Ciba, K; Cid Vidal, X; Ciezarek, G; Clarke, P E L; Clemencic, M; Cliff, H V; Closier, J; Coca, C; Coco, V; Cogan, J; Cogneras, E; Collins, P; Comerma-Montells, A; Contu, A; Cook, A; Coombes, M; Corti, G; Couturier, B; Cowan, G A; Craik, D; Cunliffe, S; Currie, R; D'Ambrosio, C; David, P; David, P N Y; De Bonis, I; De Bruyn, K; De Capua, S; De Cian, M; De Miranda, J M; De Paula, L; De Simone, P; Decamp, D; Deckenhoff, M; Degaudenzi, H; Del Buono, L; Deplano, C; Derkach, D; Deschamps, O; Dettori, F; Dickens, J; Dijkstra, H; Diniz Batista, P; Domingo Bonal, F; Donleavy, S; Dordei, F; Dosil Suárez, A; Dossett, D; Dovbnya, A; Dupertuis, F; Dzhelyadin, R; Dziurda, A; Dzyuba, A; Easo, S; Egede, U; Egorychev, V; Eidelman, S; van Eijk, D; Eisele, F; Eisenhardt, S; Ekelhof, R; Eklund, L; El Rifai, I; Elsasser, Ch; Elsby, D; Esperante Pereira, D; Falabella, A; Färber, C; Fardell, G; Farinelli, C; Farry, S; Fave, V; Fernandez Albor, V; Ferreira Rodrigues, F; Ferro-Luzzi, M; Filippov, S; Fitzpatrick, C; Fontana, M; Fontanelli, F; Forty, R; Francisco, O; Frank, M; Frei, C; Frosini, M; Furcas, S; Gallas Torreira, A; Galli, D; Gandelman, M; Gandini, P; Gao, Y; Garnier, J-C; Garofoli, J; Garra Tico, J; Garrido, L; Gascon, D; Gaspar, C; Gauld, R; Gersabeck, E; Gersabeck, M; Gershon, T; Ghez, Ph; Gibson, V; Gligorov, V V; Göbel, C; Golubkov, D; Golutvin, A; Gomes, A; Gordon, H; Grabalosa Gándara, M; Graciani Diaz, R; Granado Cardoso, L A; Graugés, E; Graziani, G; Grecu, A; Greening, E; Gregson, S; Grünberg, O; Gui, B; Gushchin, E; Guz, Yu; Gys, T; Hadjivasiliou, C; Haefeli, G; Haen, C; Haines, S C; Hall, S; Hampson, T; Hansmann-Menzemer, S; Harnew, N; Harnew, S T; Harrison, J; Harrison, P F; Hartmann, T; He, J; Heijne, V; Hennessy, K; Henrard, P; Hernando Morata, J A; van Herwijnen, E; Hicks, E; Hoballah, M; Hopchev, P; Hulsbergen, W; Hunt, P; Huse, T; Huston, R S; Hutchcroft, D; Hynds, D; Iakovenko, V; Ilten, P; Imong, J; Jacobsson, R; Jaeger, A; Jahjah Hussein, M; Jans, E; Jansen, F; Jaton, P; Jean-Marie, B; Jing, F; John, M; Johnson, D; Jones, C R; Jost, B; Kaballo, M; Kandybei, S; Karacson, M; Karbach, T M; Keaveney, J; Kenyon, I R; Kerzel, U; Ketel, T; Keune, A; Khanji, B; Kim, Y M; Knecht, M; Kochebina, O; Komarov, I; Koopman, R F; Koppenburg, P; Korolev, M; Kozlinskiy, A; Kravchuk, L; Kreplin, K; Kreps, M; Krocker, G; Krokovny, P; Kruse, F; Kucharczyk, M; Kudryavtsev, V; Kvaratskheliya, T; La Thi, V N; Lacarrere, D; Lafferty, G; Lai, A; Lambert, D; Lambert, R W; Lanciotti, E; Lanfranchi, G; Langenbruch, C; Latham, T; Lazzeroni, C; Le Gac, R; van Leerdam, J; Lees, J-P; Lefèvre, R; Leflat, A; Lefrançois, J; Leroy, O; Lesiak, T; Li, L; Li, Y; Li Gioi, L; Lieng, M; Liles, M; Lindner, R; Linn, C; Liu, B; Liu, G; von Loeben, J; Lopes, J H; Lopez Asamar, E; Lopez-March, N; Lu, H; Luisier, J; Mac Raighne, A; Machefert, F; Machikhiliyan, I V; Maciuc, F; Maev, O; Magnin, J; Malde, S; Mamunur, R M D; Manca, G; Mancinelli, G; Mangiafave, N; Marconi, U; Märki, R; Marks, J; Martellotti, G; Martens, A; Martin, L; Martín Sánchez, A; Martinelli, M; Martinez Santos, D; Massafferri, A; Mathe, Z; Matteuzzi, C; Matveev, M; Maurice, E; Mazurov, A; McCarthy, J; McGregor, G; McNulty, R; Meissner, M; Merk, M; Merkel, J; Milanes, D A; Minard, M-N; Molina Rodriguez, J; Monteil, S; Moran, D; Morawski, P; Mountain, R; Mous, I; Muheim, F; Müller, K; Muresan, R; Muryn, B; Muster, B; Mylroie-Smith, J; Naik, P; Nakada, T; Nandakumar, R; Nasteva, I; Needham, M; Neufeld, N; Nguyen, A D; Nguyen-Mau, C; Nicol, M; Niess, V; Nikitin, N; Nikodem, T; Nomerotski, A; Novoselov, A; Oblakowska-Mucha, A; Obraztsov, V; Oggero, S; Ogilvy, S; Okhrimenko, O; Oldeman, R; Orlandea, M; Otalora Goicochea, J M; Owen, P; Pal, B K; Palano, A; Palutan, M; Panman, J; Papanestis, A; Pappagallo, M; Parkes, C; Parkinson, C J; Passaleva, G; Patel, G D; Patel, M; Patrick, G N; Patrignani, C; Pavel-Nicorescu, C; Pazos Alvarez, A; Pellegrino, A; Penso, G; Pepe Altarelli, M; Perazzini, S; Perego, D L; Perez Trigo, E; Pérez-Calero Yzquierdo, A; Perret, P; Perrin-Terrin, M; Pessina, G; Petrolini, A; Phan, A; Picatoste Olloqui, E; Pie Valls, B; Pietrzyk, B; Pilař, T; Pinci, D; Playfer, S; Plo Casasus, M; Polci, F; Polok, G; Poluektov, A; Polycarpo, E; Popov, D; Popovici, B; Potterat, C; Powell, A; Prisciandaro, J; Pugatch, V; Puig Navarro, A; Qian, W; Rademacker, J H; Rakotomiaramanana, B; Rangel, M S; Raniuk, I; Rauschmayr, N; Raven, G; Redford, S; Reid, M M; dos Reis, A C; Ricciardi, S; Richards, A; Rinnert, K; Roa Romero, D A; Robbe, P; Rodrigues, E; Rodrigues, F; Rodriguez Perez, P; Rogers, G J; Roiser, S; Romanovsky, V; Romero Vidal, A; Rosello, M; Rouvinet, J; Ruf, T; Ruiz, H; Sabatino, G; Saborido Silva, J J; Sagidova, N; Sail, P; Saitta, B; Salzmann, C; Sanmartin Sedes, B; Sannino, M; Santacesaria, R; Santamarina Rios, C; Santinelli, R; Santovetti, E; Sapunov, M; Sarti, A; Satriano, C; Satta, A; Savrie, M; Savrina, D; Schaack, P; Schiller, M; Schindler, H; Schleich, S; Schlupp, M; Schmelling, M; Schmidt, B; Schneider, O; Schopper, A; Schune, M-H; Schwemmer, R; Sciascia, B; Sciubba, A; Seco, M; Semennikov, A; Senderowska, K; Sepp, I; Serra, N; Serrano, J; Seyfert, P; Shapkin, M; Shapoval, I; Shatalov, P; Shcheglov, Y; Shears, T; Shekhtman, L; Shevchenko, O; Shevchenko, V; Shires, A; Silva Coutinho, R; Skwarnicki, T; Smith, N A; Smith, E; Smith, M; Sobczak, K; Soler, F J P; Solomin, A; Soomro, F; Souza, D; Souza De Paula, B; Spaan, B; Sparkes, A; Spradlin, P; Stagni, F; Stahl, S; Steinkamp, O; Stoica, S; Stone, S; Storaci, B; Straticiuc, M; Straumann, U; Subbiah, V K; Swientek, S; Szczekowski, M; Szczypka, P; Szumlak, T; T'jampens, S; Teklishyn, M; Teodorescu, E; Teubert, F; Thomas, C; Thomas, E; van Tilburg, J; Tisserand, V; Tobin, M; Tolk, S; Topp-Joergensen, S; Torr, N; Tournefier, E; Tourneur, S; Tran, M T; Tsaregorodtsev, A; Tuning, N; Ubeda Garcia, M; Ukleja, A; Uwer, U; Vagnoni, V; Valenti, G; Vazquez Gomez, R; Vazquez Regueiro, P; Vecchi, S; Velthuis, J J; Veltri, M; Veneziano, G; Vesterinen, M; Viaud, B; Videau, I; Vieira, D; Vilasis-Cardona, X; Visniakov, J; Vollhardt, A; Volyanskyy, D; Voong, D; Vorobyev, A; Vorobyev, V; Voß, C; Voss, H; Waldi, R; Wallace, R; Wandernoth, S; Wang, J; Ward, D R; Watson, N K; Webber, A D; Websdale, D; Whitehead, M; Wicht, J; Wiedner, D; Wiggers, L; Wilkinson, G; Williams, M P; Williams, M; Wilson, F F; Wishahi, J; Witek, M; Witzeling, W; Wotton, S A; Wright, S; Wu, S; Wyllie, K; Xie, Y; Xing, F; Xing, Z; Yang, Z; Young, R; Yuan, X; Yushchenko, O; Zangoli, M; Zavertyaev, M; Zhang, F; Zhang, L; Zhang, W C; Zhang, Y; Zhelezov, A; Zhong, L; Zvyagin, A

    2012-10-12

    The effective lifetime of the B ¯(s)(0) meson in the decay mode B¯(s)(0)→J/ψf(0)(980) is measured using 1.0 fb(-1) of data collected in pp collisions at √s=7 TeV with the LHCb detector. The result is 1.700±0.040±0.026 ps, where the first uncertainty is statistical and the second systematic. As the final state is CP-odd, and CP violation in this mode is measured to be small, the lifetime measurement can be translated into a measurement of the decay width of the heavy B¯(s)(0) mass eigenstate, Γ(H)=0.588±0.014±0.009 ps(-1).

  5. Three genes coding for subunits of the membrane sector (F0) of the Escherichia coli adenosine triphosphatase complex.

    PubMed Central

    Downie, J A; Cox, G B; Langman, L; Ash, G; Becker, M; Gibson, F

    1981-01-01

    Two mutant unc alleles, unc-469 and unc-476, have been characterized as affecting a previously undescribed gene, designated uncF. The uncF gene is part of the unc operon (with the gene order being uncBFEAGDC), although some uncertainty remains as to the relative order of the uncF and uncE genes. Mutant strains carrying the uncF469 or uncF476 allele lack the 18,000-molecular-weight component of the F0 sector of the adenosine triphosphatase in the cell membrane but retain the dicyclohexylcarbodiimide-binding protein (molecular weight, 8,400). Conversely, strains carrying mutations in the uncE gene lack the dicyclohexylcarbodiimide-binding protein but retain the 18,000-molecular-weight protein in the cell membrane. Strains carrying mutations in the uncB gene have both the 18,000-molecular-weight protein and the dicyclohexylcarbodiimide-binding protein present in the cell membranes. The three proteins of the F0 portion of the adenosine triphosphatase, viz., 24,000, 18,000, and 8,400 molecular weights, became membrane associated after in vitro transcription-translation with plasmid pAN51 as template. Plasmids carrying deletions which affected the UncBFE region were isolated from plasmid pAN51 and characterized genetically. A comparison of the genes that were absent from the various deletion plasmids with the membrane-associated products formed after in vitro transcription-translation indicated that the uncB gene coded for the 24,000-molecular-weight protein and that the gene order was probably uncBFE. A correlation between length of deoxyribonucleic acid, genes present, and their products is presented in relation to plasmid pAN51. Images PMID:6450744

  6. Acetylsalicylic acid regulates MMP-2 activity and inhibits colorectal invasion of murine B16F0 melanoma cells in C57BL/6J mice: effects of prostaglandin F(2)alpha.

    PubMed

    Tsai, Chin-Shaw Stella; Luo, Shue-Fen; Ning, Chung-Chu; Lin, Chien-Liang; Jiang, Ming-Chung; Liao, Ching-Fong

    2009-08-01

    Epidemiological studies indicate that acetylsalicylic acid may reduce the risk of mortality due to colon cancers. Metastasis is the major cause of cancer death. Matrix metalloproteinases (MMPs) play important roles in tumor invasion regulation, and prostaglandin F(2)alpha (PGF(2)alpha) is a key stimulator of MMP production. Thus, we investigated whether acetylsalicylic acid regulated MMP activity and the invasion of cancer cells and whether PGF(2)alpha attenuated acetylsalicylic acid-inhibited invasion of cancer cells. Gelatin-based zymography assays showed that acetylsalicylic acid inhibited the MMP-2 activity of B16F0 melanoma cells. Matrigel-based chemoinvasion assays showed that acetylsalicylic acid inhibited the invasion of B16F0 cells. Acetylsalicylic acid can inhibit PGF(2)alpha synthesis and PGF(2)alpha is a key stimulator of MMP-2 production. Our data showed that PGF(2)alpha treatment attenuated the acetylsalicylic acid-inhibited invasion of B16F0 cells. In animal experiments, acetylsalicylic acid reduced colorectal metastasis of B16F0 cells in C57BL/6J mice by 44%. Our results suggest that PGF(2)alpha is a therapeutic target for metastasis inhibition and acetylsalicylic acid may possess anti-metastasis ability.

  7. Huge Critical Current Density and Tailored Superconducting Anisotropy in SmFeAsO(0.8)F(0.15) by Low Density Columnar-Defect Incorporation

    NASA Astrophysics Data System (ADS)

    Welp, U.; Fang, L.; Jia, Y.; Mishra, V.; Chaparro, C.; Vlasko-Vlasov, V. K.; Koshelev, A. E.; Crabtree, G. W.; Zhu, S. F.; Zhigadlo, N. D.; Katrych, S.; Karpinski, J.; Kwok, W. K.

    2014-03-01

    SmFeAsO(0.8)F(0.15) is of great interest because it has the highest transition temperature of all the iron-based superconductors. We find that the introduction of a low density of correlated nano-scale defects enhances the critical current density up to 2 × 107A/cm2 at 5 K without any suppression in the high superconducting transition temperature of 50 K and amounting to 20 % of the theoretical depairing current density. We also observed a surprising reduction in the thermodynamic superconducting anisotropy from 8 to 4 upon irradiation. A model based on anisotropic electron scattering predicts that the superconducting anisotropy can be tailored via correlated defects in semi-metallic, fully gapped type II superconductors. - We acknowledge support by the Center for Emergent Superconductivity, an EFRC funded by the US DOE, Office of Basic Energy Sciences (LF, YJ, VM, AEK, WKK, GWC), by the DOE, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357 (CC, VKV, UW), by the EC Research Council project SuperIron (JK, SK), and by the Swiss National Science Foundation and the National Center of Competence in Research MaNEP (NDZ).

  8. Synthesis, physico-chemical investigations of Co(II), Ni(II) and Cu(II) complexes and their in vitro microbial, cytotoxic, DNA cleavage studies.

    PubMed

    Bagihalli, Gangadhar B; Patil, Sangamesh A

    2010-06-01

    A series of metal complexes of cobalt(II), nickel(II), and copper(II) have been synthesized with newly derived biologically active ligands. These ligands were synthesized by the condensation of 2-amino-4-phenyl-1,3-thiazole with 8-formyl-7-hydroxy- 4-methylcoumarin. The probable structure of the complexes has been proposed on the basis of analytical and spectroscopic data (IR, UV-Vis, ESR, FAB-mass, and thermoanalytical). Electrochemical study of the complexes is also reported. Elemental analysis of the complexes confined them to stoichiometry of the type ML(2).2H(2)O [M = Co(II), Ni(II), and Cu(II)]. The Schiff base and its metal(II) complexes have been screened for their antibacterial (Escherichia coli, Staphylococcus aureus, Staphylococcus pyogenes, and Pseudomonas aeruginosa) and antifungal activities (Aspergillus niger, Aspergillus flavus, and Cladosporium) by the MIC method. The brine shrimp bioassay was carried out to study their in vitro cytotoxic properties, and also the Schiff base and its metal(II) complexes have been studied for DNA cleavage.

  9. Tunneling break-junction spectroscopy on the superconductor NdFeAs(O0.9F0.1)

    NASA Astrophysics Data System (ADS)

    Ekino, Toshikazu; Sugimoto, Akira; Okabe, Hirotaka; Shohara, Kazuhiro; Ukita, Ryuichi; Akimitsu, Jun; Gabovich, Alexander M.

    2010-12-01

    Tunnel break-junction method has been adopted to study polycrystalline samples of iron-oxypnictide superconductor NdFeAs(O0.9F0.1) with Tc=48K. Measurements were carried out at 4.2 K. Break-junction (BJ) conductance versus voltage curves showed gap-edge peaks with the peak-to-peak distances V=4Δ/e=28-40mV at 4.2 K, where 2Δ(T) is the superconducting energy gap, e>0 is the elementary charge. This yields 2Δ(0)=14-20meV, so that the gap ratio 2Δ(0)/kBTc is about 4.1±0.7,kB being the Boltzmann constant. This ratio implies strong-coupling superconductivity in the framework of Bardeen-Cooper-Schrieffer theory, being, however, much smaller than that for high-Tc copper oxides. This suggests a significant difference in the pairing mechanism between those classes of materials.

  10. Structure of the cytosolic part of the subunit b-dimer of Escherichia coli F0F1-ATP synthase.

    PubMed

    Hornung, Tassilo; Volkov, Oleg A; Zaida, Tarek M A; Delannoy, Sabine; Wise, John G; Vogel, Pia D

    2008-06-01

    The structure of the external stalk and its function in the catalytic mechanism of the F(0)F(1)-ATP synthase remains one of the important questions in bioenergetics. The external stalk has been proposed to be either a rigid stator that binds F(1) or an elastic structural element that transmits energy from the small rotational steps of subunits c to the F(1) sector during catalysis. We employed proteomics, sequence-based structure prediction, molecular modeling, and electron spin resonance spectroscopy using site-directed spin labeling to understand the structure and interfacial packing of the Escherichia coli b-subunit homodimer external stalk. Comparisons of bacterial, cyanobacterial, and plant b-subunits demonstrated little sequence similarity. Supersecondary structure predictions, however, show that all compared b-sequences have extensive heptad repeats, suggesting that the proteins all are capable of packing as left-handed coiled-coils. Molecular modeling subsequently indicated that b(2) from the E. coli ATP synthase could pack into stable left-handed coiled-coils. Thirty-eight substitutions to cysteine in soluble b-constructs allowed the introduction of spin labels and the determination of intersubunit distances by ESR. These distances correlated well with molecular modeling results and strongly suggest that the E. coli subunit b-dimer can stably exist as a left-handed coiled-coil.

  11. Characteristics of low-latitude whistlers and their relation with f0F2 and magnetic activity

    SciTech Connect

    Bao, Z.; Wang, T.; Xu, J.; Chen, S.; Liang, B.

    1982-01-01

    Characteristics of low-latitude whistlers observed with instrumentation at three locations in China over a three-year period are discussed. The whistler maxima were always detected after midnight, local time, and none occurred during the daytime or evening. The rate of occurrence at the three sites was less than 1/min. A similarity was found between the diurnal variation of the median value of the critical frequency of the F2 region and that of the whistler dispersion. A set of algebraic equations was employed to calculate the electron concentration in the equatorial plane at the top of the propagation path (Neq) and the tube content (NT). The whistler dispersion and f0F2 (the critical frequency) were then converted into Neq and NT, resulting in calculated median values which agreed with satellite observations. Finally, a positive correlation was obtained between the daily variation of Kp and whistler dispersion, supporting the hypothesis that the whistler occurrence rate at low latitudes peaks one or two days after a geomagnetic storm day.

  12. Glueball nature of the σ /f0 (600) from ππ and γγ scatterings

    NASA Astrophysics Data System (ADS)

    Mennessier, G.; Narison, S.; Ochs, W.

    2008-07-01

    We estimate the I = 0 scalar meson σ /f0 (600) parameters from ππ and γγ scattering data below 700 MeV using an improved analytic K-matrix model. A fit of the hadronic data gives a complex pole mass Mσ = 422 - i 290MeV, while simultaneous best fits of the γγ →π+π- ,π0π0 data give a direct width of (0.13 ± 0.05)keV, a rescattering component of (2.7 ± 0.4)keV and a total (direct + rescattering) width of (3.9 ± 0.6)keV. “Running” these results to the physical real axis, the small “direct”γγ and the large hadronic widths at the “on-shell” mass are compatible with QCD spectral sum rules (QSSR) and some low-energy theorems (LET) expectations for an unmixed lowest mass glueball/gluonium σB of a mass around 1 GeV and a large OZI-violation decay into ππ.

  13. Global model of low-frequency chorus (fLHR<f<0.1fce) from multiple satellite observations

    PubMed Central

    Meredith, Nigel P; Horne, Richard B; Li, Wen; Thorne, Richard M; Sicard-Piet, Angélica

    2014-01-01

    Whistler mode chorus is an important magnetospheric emission, playing a dual role in the acceleration and loss of relativistic electrons in the Earth's outer radiation belt. Chorus is typically generated in the equatorial region in the frequency range 0.1–0.8 fce, where fce is the local electron gyrofrequency. However, as the waves propagate to higher latitudes, significant wave power can occur at frequencies below 0.1fce. Since this wave power is largely omitted in current radiation belt models, we construct a global model of low-frequency chorus, fLHR<f<0.1fce, using data from six satellites. We find that low-frequency chorus is strongest, with an average intensity of 200 pT2, in the prenoon sector during active conditions at midlatitudes (20°<|λm|<50°) from 4

  14. Characterization of oligomeric forms from mammalian F0F1ATP synthase by BN-PAGE: the role of detergents.

    PubMed

    Bisetto, Elena; Giorgio, Valentina; Di Pancrazio, Francesca; Mavelli, Irene; Lippe, Giovanna

    2007-12-01

    It is now widely accepted that F0F1ATPsynthase is present in membrane, beside as monomers, in homo-dimeric and higher homo-oligomeric forms, which probably play critical roles in determining mitochondrial morphology. One-step mild detergent extraction followed by blue native electrophoresis (BN-PAGE) is a very interesting tool for studying the native membrane protein assemblies which can be associated with second/third-dimensional SDS-PAGE, immunoblotting, in-gel enzyme activity staining and mass spectrometry analyses. By combining these techniques, we resolved monomers and higher oligomeric forms of ATPsynthase from bovine heart mitochondria. However, a critical point is the choice of the detergents, which strongly influence the protein pattern of BN-PAGE. By using Triton X-100 we obtained that, in spite of the same subunit composition, monomers have a much lower specific activity than dimers and the two forms have a different pattern of tyrosine phosphorylation, suggesting that monomers and dimers are functionally distinct in membrane. In addition, enzyme self-association appeared to occur independently from the binding to ATPsynthase of the inhibitor protein IF1. Dodecylmaltoside was optimal to extract the enzyme from single biopsy samples, allowing us to demonstrate that IF1 plays a central role in regulating the enzyme activity in heart in vivo. Only low concentration of digitonin maintained significant amounts of ATPsynthase oligomers, which seemed to retain intact their native catalytic properties.

  15. Piceatannol, a stilbene phytochemical, inhibits mitochondrial F0F1-ATPase activity by targeting the F1 complex.

    PubMed

    Zheng, J; Ramirez, V D

    1999-08-02

    Piceatannol is a stilbene phytochemical from the seeds of Euphorbia lagascae, previously identified as an antileukemic principle. Piceatannol is considered an inhibitor of several tyrosine kinases. We recently reported that resveratrol, another stilbene phytoalexin from grape seeds, was an inhibitor of ATP synthase. Here, we demonstrated that piceatannol potently inhibited the rat brain mitochondrial F0F1-ATPase activity in both solubilized and submitochondrial preparations (IC50 of 8-9 microM), while having relatively small effect on the Na(+), K(+)-ATPase activity of porcine cerebral cortex (no effect up to 7 microM). Piceatannol inhibited the ATPase activity of the purified rat liver F1 with IC50 of about 4 microM, while resveratrol was slightly less active (IC50 of about 14 microM). Our results indicate that piceatannol and resveratrol inhibit the F-type ATPase by targeting the F1 sector, which is located to the inner membrane of mitochondria and plasma membrane of normal endothelial cells and several cancer cell lines. This mechanism could potentially contribute to the multiple effects of these chemopreventive phytochemicals. Copyright 1999 Academic Press.

  16. A comprehensive investigation on adsorption of Ca (II), Cr (III) and Mg (II) ions by 3D porous nickel films.

    PubMed

    Lai, Chuan; Guo, Xiaogang; Xiong, Zhongshu; Liu, Changlu; Zhu, Hui; Wu, Mei; Zhang, Daixiong

    2016-02-01

    The present study reports the removal of Ca (II), Cr (III), Mg (II) ions from aqueous solution using 3D-porous nickel films (3DNFs) as a novel adsorbent material prepared by hydrogen bubble dynamic template (HBDT) method at room temperature. The structure morphology and the phase constitution of 3DNFs were characterized by FESEM, EDS and XRD. Adsorption process of Ca (II), Cr (III), Mg (II) ions was fast as the equilibrium was established within 30min, and the maximum adsorption at equilibrium was 44.1mg/g, 46.4mg/g and 32.7mg/g, respectively. The adsorption kinetics well fitted using a pseudo second-order kinetic model. The adsorption isotherm data of all the three metals fit well the Langmuir and Freundlich adsorption isotherm model. It was found out that kinetics of adsorption varies with initial concentration of metal ions. Thermodynamic parameters (i.e., the standard Gibbs free energies (ΔG), enthalpy change (ΔH), standard entropy change (ΔS)) were also evaluated. Thermodynamic analysis indicated that a high temperature is favored for the adsorption of metal ions by 3DNFs. These results suggest that 3DNFs have good potential application in effective adsorption of metal ions with satisfactory results.

  17. Investigation into solar type II radio bursts recorded by CALLISTO-BR

    NASA Astrophysics Data System (ADS)

    Silva, R. D. C.; Fernandes, F. C. R.; Selhorst, C. L.

    2012-04-01

    This work brings out the outcomes of investigation of two solar type II radio bursts observed on October 16, 2010 (19:12:54 UT) and on February 14, 2011 (15:27:05 UT) by CALLISTO-BR (Compound Astronomical Low frequency Low Cost Instrument for Spectroscopy and Transportable Observatory) spectrometer operating in the frequency range of 45-870 MHz. The first event comprises a burst with typical type II starting frequency and clues of partial reabsorption of the fundamental frequency band. The second one consists of a solar split-band type II radio burst with whole reabsorption of the fundamental frequency band. Both events were preceded by solar type III radio bursts. Among the physical parameters determined for the propagation of the associated shock and its region are: source speed of the order of 1127 ± 76 km s-1 and 889 ± 31 km s-1; electron number density of (5.17 ± 0.33) x 107 cm-3 and (2.46 ± 0.07) x 108cm-3; Alfvén speed of the order of 287 ± 11 km s-1 and 398 ± 911 km s-1; Mach number of 1.05 ± 0.01 and 1.12 ± 0.01; magnetic field strength of 0.95 ± 0.03 G and 2.85 ± 0.07 G; and temperature of (3.79 ± 1.02) x 107 K and (1.69 ± 0.39) x 107 K. The results, compared to those reported in the literature, are consistent. The source speed indeed outdoes the Alfvén speed with a density jump at the shock front which is suitable (< 4) for MHD (magnetohydrodynamic) shocks for both events.

  18. Early investigational therapeutics for gastrointestinal motility disorders: from animal studies to Phase II trials.

    PubMed

    Valentin, Nelson; Acosta, Andres; Camilleri, Michael

    2015-06-01

    The most common gastrointestinal disorders that include evidence of dysmotility include: gastroparesis, the lower functional gastrointestinal disorders associated with altered bowel function (such as chronic [functional] diarrhea, chronic idiopathic constipation) and opioid-induced constipation. These conditions, which are grouped as gastrointestinal motility and functional disorders, are characterized by abnormal motor, sensory or secretory functions that alter bowel function and result in a significant disease burden, since currently available treatments do not completely alleviate symptoms. New drugs are being developed for these disorders, targeting mechanisms involved in the pathophysiology of these diseases, specifically, motor function, intestinal secretion and bile acid modulation. The article provides a brief overview of motility disorders and the drugs approved and currently available for these indications. It also provides an evaluation of the efficacy, safety and possible mechanisms of the drugs currently under investigation for the treatment of gastroparesis, chronic diarrhea, chronic idiopathic constipation and opioid-induced constipation, based on animal to Phase II studies. Medications with complete Phase III trials are excluded from this discussion. Treatment of gastrointestinal motility disorders requires the understanding of the pathophysiological mechanisms, biomarkers to identify subgroups of these disorders and robust pharmacological studies from animal to Phase II studies. These are prerequisites for the development of efficacious medications and individualizing therapy in order to enhance the treatment of these patients.

  19. Clinical and genetic investigation of families with type II Waardenburg syndrome

    PubMed Central

    CHEN, YONG; YANG, FUWEI; ZHENG, HEXIN; ZHOU, JIANDA; ZHU, GANGHUA; HU, PENG; WU, WEIJING

    2016-01-01

    The present study aimed to investigate the molecular pathology of Waardenburg syndrome type II in three families, in order to provide genetic diagnosis and hereditary counseling for family members. Relevant clinical examinations were conducted on the probands of the three pedigrees. Peripheral blood samples of the probands and related family members were collected and genomic DNA was extracted. The coding sequences of paired box 3 (PAX3), microphthalmia-associated transcription factor (MITF), sex-determining region Y-box 10 (SOX10) and snail family zinc finger 2 (SNAI2) were analyzed by polymerase chain reaction and DNA sequencing. The heterozygous mutation, c.649_651delAGA in exon 7 of the MITF gene was detected in the proband and all patients of pedigree 1; however, no pathological mutation of the relevant genes (MITF, SNAI2, SOX10 or PAX3) was detected in pedigrees 2 and 3. The heterozygous mutation c.649_651delAGA in exon 7 of the MITF gene is therefore considered the disease-causing mutation in pedigree 1. However, there are novel disease-causing genes in Waardenburg syndrome type II, which require further research. PMID:26781036

  20. Early Investigational Therapeutics for Gastrointestinal Motility Disorders: From Animal Studies to Phase II Trials

    PubMed Central

    Valentin, Nelson; Acosta, Andres; Camilleri, Michael

    2015-01-01

    Introduction The most common gastrointestinal disorders which include evidence of dysmotility include: gastroparesis, the lower functional gastrointestinal disorders associated with altered bowel function [such as chronic (functional) diarrhea, chronic idiopathic constipation (CIC)], and opioid induced constipation (OIC). These conditions, which are grouped as gastrointestinal motility and functional disorders, are characterized by abnormal motor, sensory, or secretory functions that alter bowel function and result in a significant disease burden, since currently available treatments do not completely alleviate symptoms. New drugs are being developed for these disorders, targeting mechanisms involved in the pathophysiology of these diseases, specifically, motor function, intestinal secretion and bile acid modulation. Areas Covered The article provides a brief overview of motility disorders and the drugs approved and currently available for these indications. It also provides an evaluation of the efficacy, safety and possible mechanisms of the drugs currently under investigation for the treatment of gastroparesis, chronic diarrhea, CIC and OIC, based on animal to phase II studies. Medications with complete phase III trials are excluded from this discussion. Expert opinion Treatment of gastrointestinal motility disorders requires the understanding of the pathophysiological mechanisms, biomarkers to identify subgroups of these disorders, and robust pharmacological studies from animal to phase II studies. These are prerequisites for the development of efficacious medications and individualizing therapy in order to enhance the treatment of these patients. PMID:25971881

  1. Final Phase II Report : QuickSite{reg_sign} investigation, Centralia, Kansas.

    SciTech Connect

    LaFreniere, L.

    2004-04-01

    District No.3. Therefore, local residents are not drinking or using the contaminated groundwater detected at the former facility. The Environmental Research Division of Argonne National Laboratory is performing the investigation at Centralia on behalf of the CCC/USDA. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy (DOE). The CCC/USDA has entered into an interagency agreement with DOE, under which Argonne provides technical assistance to the CCC/USDA with environmental site characterization and remediation at its former grain storage facilities. At these former facilities, Argonne is applying its QuickSite{reg_sign} environmental site characterization methodology. QuickSite is Argonne's proprietary implementation system for the expedited site characterization process. This methodology has been applied successfully at a number of former CCC/USDA facilities in Nebraska and Kansas and has been adopted by the American Society for Testing and Materials (ASTM 1998) as standard practice for environmental site characterization. Argonne's investigations are conducted with a phased approach. Phase I focuses primarily on the investigation and evaluation of geology, hydrogeology, and hydrogeochemistry to identify potential contaminant pathways at a site. Phase II focuses on delineating the contamination present in both soil and aquifers along the potential migration pathways. Phase I of Argonne's investigation was conducted in March-April 2002. The results and findings of the Phase I investigation at Centralia were reported previously (Argonne 2003). This report documents the findings of the Phase II activities at Centralia. Section 1 provides a brief history of the area, a review of the Phase I results and conclusions, technical objectives for the Phase II investigation, and a brief description of the sections contained in this report. Section 2 describes the investigative methods used during the Phase

  2. Final Phase II report : QuickSite(R) investigation, Everest, Kansas.

    SciTech Connect

    LaFreniere, L. M.

    2003-11-01

    this reason, the CCC/USDA is conducting an environmental site investigation to determine the source(s) and extent of the carbon tetrachloride contamination at Everest and to assess whether the contamination requires remedial action. The investigation at Everest is being performed by the Environmental Research Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy (DOE). The CCC/USDA has entered into an interagency agreement with DOE, under which Argonne provides technical assistance to the CCC/USDA with environmental site characterization and remediation at its former grain storage facilities. At these facilities, Argonne is applying its QuickSite{reg_sign} environmental site characterization methodology. This methodology has been applied successfully at a number of former CCC/USDA facilities in Kansas and Nebraska and has been adopted by the American Society for Testing and Materials (ASTM 1998) as standard practice for environmental site characterization. Phase I of the QuickSite{reg_sign} investigation examined the key geologic, hydrogeologic, and hydrogeochemical relationships that define potential contaminant migration pathways at Everest (Argonne 2001). Phase II of the QuickSite{reg_sign} investigation at Everest was undertaken with the primary goal of delineating and improving understanding of the distribution of carbon tetrachloride contamination in groundwater at this site and the potential source area(s) that might have contributed to this contamination. To address this goal, four specific technical objectives were developed to guide the Phase II field studies. Sampling of near-surface soils at the former Everest CCC/USDA facility that was originally planned for Phase I had to be postponed until October 2000 because of access restrictions. Viable vegetation was not available for sampling then. This period is termed the first session of Phase II

  3. VIDA II: a computerised diagnostic recording system for veterinary investigation centres in Great Britain.

    PubMed

    Hall, S A; Dawson, P S; Davies, G

    1980-03-22

    "Veterinary Investigation Diagnosis Analysis" II is a computerised recording system for all the diagnoses made at 33 Government diagnostic laboratories in Great Britain. It was created in 1975 and the records of 150,000 specimens are stored on it each year. The system depends on an agreed list of 393 possible diagnoses (101 cattle, 96 sheep, 72 pigs, 71 birds and 53 for other species). Diagnostic records are sent each month to a computer centre which produces an annual record of all diagnoses made and a monthly record of the number of submissions and financial charges. The computer file can be interrogated from a terminal at the epidemiology unit Weybridge and the diagnostic records are available to research workers.

  4. Chip PCR. II. Investigation of different PCR amplification systems in microbabricated silicon-glass chips.

    PubMed Central

    Cheng, J; Shoffner, M A; Hvichia, G E; Kricka, L J; Wilding, P

    1996-01-01

    We examined PCR in silicon dioxide-coated silicon-glass chips (12 microl in volume with a surface to volume ratio of approximately 17.5 mm(2)/microl) using two PCR reagent systems: (i) the conventional reagent system using Taq DNA polymerase; (ii) the hot-start reagent system based on a mixture of TaqStart antibody and Taq DNA polymerase. Quantitative results obtained from capillary electrophoresis for the expected amplification products showed that amplification in microchips was reproducible (between batch coefficient of variation 7.71%) and provided excellent yields. We also used the chip for PCR directly from isolated intact human lymphocytes. The amplification results were comparable with those obtained using extracted human genomic DNA. This investigation is fundamental to the integration of sample preparation, polynucleotide amplification and amplicate detection on a microchip. PMID:8628666

  5. Evidence for the Synthesis of ATP by an F0F1 ATP Synthase in Membrane Vesicles from Halorubrum Saccharovorum

    NASA Technical Reports Server (NTRS)

    Faguy, David; Lawson, Darion; Hochstein, Lawrence I.; Chang, Sherwood (Technical Monitor)

    1996-01-01

    Vesicles prepared in a buffer containing ADP, Mg(2+) and Pi synthesized ATP at an initial rate of 2 nmols/min/mg protein after acidification of the bulk medium (pH 8 (right arrow) 4). The intravesicular ATP concentration reached a steady state after about 30 seconds and slowly declined thereafter. ATP synthesis was inhibited by low concentrations of dicyclohexylcarbodiimide and m-chlorophenylhydrazone indicating that synthesis took place in response to the proton gradient. NEM and PCMS, which inhibit vacuolar ATPases and the vacuolar-like ATPases of extreme halophiles, did not affect ATP synthesis, and, in fact, produced higher steady state levels of ATP. This suggested that two ATPase activities were present, one which catalyzed ATP synthesis and one that caused its hydrolysis. Azide, a specific inhibitor of F0F1 ATP Synthases, inhibited halobacterial ATP synthesis. The distribution of acridine orange as imposed by a delta pH demonstrated that azide inhibition was not due to the collapse of the proton gradient due to azide acting as a protonophore. Such an effect was observed, but only at azide concentrations higher than those that inhibited ATP synthesis. These results confirm the earler observations with cells of H. saccharovorum and other extreme halophiles that ATP synthesis is inconsistent with the operation of a vacuolar-like ATPase. Therefore, the observation that a vacuolar-like enzyme is responsible for ATP synthesis (and which serves as the basis for imputing ATP synthesis to the vacuolar-like ATPases of the extreme halophiles, and the Archaea in general) should be taken with some degree of caution.

  6. A BCS-like gap in the superconductor SmFeAsO0.85F0.15.

    PubMed

    Chen, T Y; Tesanovic, Z; Liu, R H; Chen, X H; Chien, C L

    2008-06-26

    Since the discovery of superconductivity in the high-transition-temperature (high-T(c)) copper oxides two decades ago, it has been firmly established that the CuO(2) plane is essential for superconductivity and gives rise to a host of other very unusual properties. A new family of superconductors with the general composition of LaFeAsO(1-x)F(x) has recently been discovered and the conspicuous lack of the CuO(2) planes raises the tantalizing question of a different pairing mechanism in these oxypnictides. The superconducting gap (its magnitude, structure, and temperature dependence) is intimately related to pairing. Here we report the observation of a single gap in the superconductor SmFeAsO(0.85)F(0.15) with T(c) = 42 K as measured by Andreev spectroscopy. The gap value of 2Delta = 13.34 +/- 0.3 meV gives 2Delta/k(B)T(c) = 3.68 (where k(B) is the Boltzmann constant), close to the Bardeen-Cooper-Schrieffer (BCS) prediction of 3.53. The gap decreases with temperature and vanishes at T(c) in a manner consistent with the BCS prediction, but dramatically different from that of the pseudogap behaviour in the copper oxide superconductors. Our results clearly indicate a nodeless gap order parameter, which is nearly isotropic in size across different sections of the Fermi surface, and are not compatible with models involving antiferromagnetic fluctuations, strong correlations, the t-J model, and the like, originally designed for the high-T(c) copper oxides.

  7. Evidence for the Synthesis of ATP by an F0F1 ATP Synthase in Membrane Vesicles from Halorubrum Saccharovorum

    NASA Technical Reports Server (NTRS)

    Faguy, David; Lawson, Darion; Hochstein, Lawrence I.; Chang, Sherwood (Technical Monitor)

    1996-01-01

    Vesicles prepared in a buffer containing ADP, Mg(2+) and Pi synthesized ATP at an initial rate of 2 nmols/min/mg protein after acidification of the bulk medium (pH 8 (right arrow) 4). The intravesicular ATP concentration reached a steady state after about 30 seconds and slowly declined thereafter. ATP synthesis was inhibited by low concentrations of dicyclohexylcarbodiimide and m-chlorophenylhydrazone indicating that synthesis took place in response to the proton gradient. NEM and PCMS, which inhibit vacuolar ATPases and the vacuolar-like ATPases of extreme halophiles, did not affect ATP synthesis, and, in fact, produced higher steady state levels of ATP. This suggested that two ATPase activities were present, one which catalyzed ATP synthesis and one that caused its hydrolysis. Azide, a specific inhibitor of F0F1 ATP Synthases, inhibited halobacterial ATP synthesis. The distribution of acridine orange as imposed by a delta pH demonstrated that azide inhibition was not due to the collapse of the proton gradient due to azide acting as a protonophore. Such an effect was observed, but only at azide concentrations higher than those that inhibited ATP synthesis. These results confirm the earler observations with cells of H. saccharovorum and other extreme halophiles that ATP synthesis is inconsistent with the operation of a vacuolar-like ATPase. Therefore, the observation that a vacuolar-like enzyme is responsible for ATP synthesis (and which serves as the basis for imputing ATP synthesis to the vacuolar-like ATPases of the extreme halophiles, and the Archaea in general) should be taken with some degree of caution.

  8. Acoustic measurement method in investigation of optical phenomena in a modulated CO II laser plasma

    NASA Astrophysics Data System (ADS)

    Wojaczek, Dorota A.; Plinski, Edward F.; Rosinski, Lukasz; Trawinski, Robert

    2007-02-01

    The paper describes the results of investigations of optical phenomena on an RF excited slab-waveguide CO II laser. The experiments are performed in two optical arrangements: two-mirror resonator and three-mirror one. The main purpose of the experiments is to check possibilities to observe the optical phenomena using a microphone. The laser plasma is modulated with a self-mixing signal in the three-mirror resonator. The response of the microphone is observed and analyzed. Detection of the laser signature phenomenon with the microphone is experimentally considered. The experiments are done at cw regime of the laser. The investigations are performed at pulse operation of the laser, as well. The response of the microphone is analyzed. It is checked how the laser pulse is reconstructed at a profile of the microphone signal. The output laser pulse with a mapped laser signature in the laser pulse profile is compared to the microphone signal shape. The presence of the laser signature at the acoustic signal is investigated.

  9. Upper limit for the cross-section of the overlapping scalar resonances f0(980) and a0(980) produced in proton proton collisions in the range of the reaction threshold

    NASA Astrophysics Data System (ADS)

    Moskal, P.; Adam, H.-H.; Budzanowski, A.; Czyzykiewicz, R.; Grzonka, D.; Janusz, M.; Jarczyk, L.; Kamys, B.; Khoukaz, A.; Kilian, K.; Kolf, C.; Kowina, P.; Lister, T.; Oelert, W.; Piskor-Ignatowicz, C.; Przerwa, J.; Quentmeier, C.; Rozek, T.; Santo, R.; Schepers, G.; Sefzick, T.; Siemaszko, M.; Smyrski, J.; Strzalkowski, A.; Täschner, A.; Winter, P.; Wolke, M.; Wüstner, P.; Zipper, W.

    2003-09-01

    Utilizing a missing mass technique we investigate the pp rightarrow ppX reaction scanning beam energies in the range permitting to create a mass close to that of the f0(980) and a0(980) scalar resonances, but still below the K+K- threshold where they decay dominantly into pipi and pieta mesons, respectively. Prior to the data analysis we introduce a notion of the close to threshold total cross-section for broad resonances. We estimated for the overlapping mesons a0 and f0 the total cross-section to be smaller than 430 nb at excess energy of Q = 5 MeV. The experiment has been performed at the Cooler Synchrotron (COSY) using the COSY-11 facility.

  10. Superconducting phase fluctuations in SmFeAsO0.8F0.2 from diamagnetism at a low magnetic field above Tc

    NASA Astrophysics Data System (ADS)

    Prando, G.; Lascialfari, A.; Rigamonti, A.; Romanó, L.; Sanna, S.; Putti, M.; Tropeano, M.

    2011-08-01

    Superconducting fluctuations (SFs) in SmFeAsO0.8F0.2 (characterized by superconducting transition temperature Tc≃52.3 K) are investigated by means of isothermal high-resolution dc magnetization measurements. The diamagnetic response above Tc to magnetic fields up to 1 T is similar to that previously reported for underdoped cuprate superconductors and justified in terms of metastable superconducting islands of nonzero order parameter lacking long-range coherence because of strong phase fluctuations. In the high-field regime (H≳1.5 T) scaling arguments predicted on the basis of the Ginzburg-Landau theory for conventional SFs are confirmed, at variance with what is observed in the low-field regime. This fact shows that two different phenomena are simultaneously present in the fluctuating diamagnetism, namely the phase SFs of novel character and the conventional SFs. High magnetic fields (1.5 T ≲H≪Hc2) are found to suppress the former while leaving unaltered the latter.

  11. The promoter of the operon encoding the F0F1 ATPase of Streptococcus pneumoniae is inducible by pH.

    PubMed

    Martín-Galiano, A J; Ferrándiz, M J; de la Campa, A G

    2001-09-01

    The genes encoding the subunits of the F0F1 membrane ATPase of Streptococcus pneumoniae were cloned and sequenced. The eight genes, transcribed to one mRNA, are organized in an operon encoding the c, a, b, delta, alpha, gamma, beta and epsilon subunits of 66, 238, 165, 178, 501, 292, 471 and 139 amino acid residues, respectively, that were expressed in an Escherichia coli system. To investigate the role of the ATPase in the regulation of the intracellular pH, the expression of the operon between pH 5.7 and 7.5 was studied. An increase in both the ATPase activity and the amount of the alpha and beta F1 subunits as shown by Western blot analysis was observed as the pH decreased. These increases were accompanied by an increase in the atp-specific mRNA, as shown by Northern blot and slot-blot analysis. Primer extension experiments and transcriptional fusions between the atp promoter and the reporter cat gene demonstrated that this pH-dependent increase in the mRNA was regulated at the level of initiation of transcription. Transcription of the operon occurs from a promoter with a consensus -35 box (TTGACA) and a -10 box (TACACT) that differs from the consensus (TATAAT). A point mutation at the -10 box of the promoter (change to TGCACT) avoided this increase, suggesting a role for this sequence in the pH-inducible regulation.

  12. Granularity and vortex dynamics in LaFeAsO0.92F0.08 probed by harmonics of the ac magnetic susceptibility

    NASA Astrophysics Data System (ADS)

    Polichetti, Massimiliano; Adesso, Maria G.; Zola, Danilo; Luo, Jianlin; Chen, G. F.; Li, Zheng; Wang, N. L.; Noce, Canio; Pace, Sandro

    2008-12-01

    Fundamental and higher harmonics of the ac magnetic susceptibility have been measured on LaFeAsO0.92F0.08 samples as a function of the temperature, at various amplitudes and frequencies of the ac magnetic field, with a small superimposed dc field parallel to the ac field. The granularity of the samples has been investigated and the intergrain and intragrain contributions have been clearly individuated looking at both the first and the third harmonics. The vortex dynamics has been also analyzed, and a comparison with the magnetic behavior of both the MgB2 and the cuprate superconductors has been performed. Some vortex dissipative phenomena, i.e., the thermally activated flux flow and the flux creep, have been detected in the presented experimental data, similar to what have been obtained on YBCO. Nevertheless, although the general behavior is similar, several differences have been also evidenced between these different classes of superconductors, mainly in the third harmonics. We infer that different vortex dynamics has to be included into the analysis of the magnetic response in this iron-based material.

  13. Investigation of the isotopic ratio 129I/I in petrified wood.

    PubMed

    Jabbar, Tania; Steier, Peter; Wallner, Gabriele; Cichocki, Otto; Sterba, Johannes H

    2013-06-01

    In fossil specimens, measurements of the natural isotopic ratio (129)I/I may provide a method to estimate the age of sample. The motivation for measuring the isotopic composition ((129)I/I) of petrified wood samples collected from Austria was to check this feasibility. Alkaline fusion together with anion exchange was used to extract iodine from the sample. Typical sample size for this study was 10-90 g. An atomic ratio as low as 10(-14) was determined using accelerator mass spectrometry (AMS). Uranium concentrations measured by instrumental neutron activation analysis (INAA) and α-spectrometry were found to be less than 3 mg kg(-1), therefore the contribution from fissiogenic (129)I was small and an estimation of ages was based on the decrease of the initial ratio (due to decay of the cosmogenic (129)I in a closed system) after subtraction of the fissiogenic (129)I. The value of the prenuclear ratio is crucial for the use of the (129)I system for dating purposes in the terrestrial environment. From the preanthropogenic (initial) ratio of 1.5 × 10(-12) of the hydrosphere and the results of the present study for the samples from Altenburg (1.05 × 10(-12)) and Fuerwald (6.16 × 10(-13)), respective ages of 8 ± 2.2 and 20.2 ± 2.2 million years were derived. Since samples were collected from a stratum deposited in the Upper Oligocene/Ergerien period (~25-30 million years ago), it can be concluded that these isotopic ratios do not show ages but an elapsed time since fossil wood was isolated from mineral rich water. Paleontological investigation shows that samples from Altenburg had mixed characteristics of old and modern Tertiary plants, thus an origin from a younger stratum re-sedimented with Oligocene cannot be excluded. However, the sample from Drasenhofen reflects that the (129)I/I system might not always be suitable for the dating of petrified wood sample due to fixation of anthropogenic (129)I into surface fractures.

  14. Photometric and Period Investigation of the Late F-type Overcontact Binary II UMa

    NASA Astrophysics Data System (ADS)

    Zhou, X.; Qian, S.-B.; Zhang, J.; Zhang, B.; Kreiner, J.

    2016-03-01

    II UMa is a late F-type (F5) contact binary with a close-in tertiary and a distant visual companion. According to the four-color (B V RcIc) light curves’ solutions of II UMa, it is a high fill-out (f = 86.6%) and low-mass ratio (q = 0.172) contact binary system, which indicates that it is at the late evolutionary stage of late-type tidal-locked binary stars. The masses of the primary star and secondary star are calculated to be {M}1=1.99{M}⊙ and {M}2=0.34{M}⊙ . The primary star has evolved from the zero-age main sequence, but it still appeared before the terminal-age main sequence, and the secondary star is even more evolved. Considering the mass ratio ({M}3/{M}1=0.67) obtained by spectroscopic observations, the mass of the close-in tertiary is estimated to be {M}3=1.34{M}⊙ . The period variations of the binary system are investigated for the first time. According to the observed-calculated (O-C) curve analysis, a continuous period increase at a rate of {dP}/{dt}=4.88× {10}-7 {day} {{yr}}-1 is determined. The parabolic variation in the O-C curve may be part of a cyclic period of change, or the combined period of change of a parabolic variation and a cyclic one. More instances of minimum light are needed to confirm this. The presence of the tertiary component may play an important role in the formation and evolution of this binary system by drawing angular momentum from the central system during the pre-contact stage.

  15. A Multi-wavelength Investigation of RCW175: An H II Region Harboring Spinning Dust Emission

    NASA Astrophysics Data System (ADS)

    Tibbs, C. T.; Paladini, R.; Compiègne, M.; Dickinson, C.; Alves, M. I. R.; Flagey, N.; Shenoy, S.; Noriega-Crespo, A.; Carey, S.; Casassus, S.; Davies, R. D.; Davis, R. J.; Molinari, S.; Elia, D.; Pestalozzi, M.; Schisano, E.

    2012-08-01

    Using infrared, radio continuum, and spectral observations, we performed a detailed investigation of the H II region RCW175. We determined that RCW175, which actually consists of two separate H II regions, G29.1-0.7 and G29.0-0.6, is located at a distance of 3.2 ± 0.2 kpc. Based on the observations we infer that the more compact G29.0-0.6 is less evolved than G29.1-0.7 and was possibly produced as a result of the expansion of G29.1-0.7 into the surrounding interstellar medium. We compute a star formation rate for RCW175 of (12.6 ± 1.9) × 10-5 M ⊙ yr-1, and identified six possible young stellar object candidates within its vicinity. Additionally, we estimate that RCW175 contains a total dust mass of 215 ± 53 M ⊙. RCW175 has previously been identified as a source of anomalous microwave emission (AME), an excess of emission at centimeter wavelengths often attributed to electric dipole radiation from the smallest dust grains. We find that the AME previously detected in RCW175 is not correlated with the smallest dust grains (polycyclic aromatic hydrocarbons or small carbonaceous dust grains), but rather with the exciting radiation field within the region. This is a similar result to that found in the Perseus molecular cloud, another region which harbors AME, suggesting that the radiation field may play a pivotal role in the production of this new Galactic emission mechanism. Finally, we suggest that these observations may hint at the importance of understanding the role played by the major gas ions in spinning dust models.

  16. Investigational drugs in phase II clinical trials for the treatment of neuroblastoma.

    PubMed

    Amoroso, Loredana; Haupt, Riccardo; Garaventa, Alberto; Ponzoni, Mirco

    2017-11-01

    Neuroblastoma (NB) is an embryonal tumor originating from undifferentiated neural crest cell, highly heterogeneous ranging from spontaneous regression to progression despite multimodal treatments. Approximately, 20% of patients are refractory to frontline therapy and 50% will relapse/progress after an initial response. The overall five year survival for high-risk neuroblastoma ranges from 35-45%. Despite enhanced understanding of NB biology and the addition of myeloablative chemotherapy, isotretinoin and immunotherapy, survival for high risk NB remains less than 50%. Areas covered: This review summarizes and gives a critical overview of phase II trials investigating therapies for relapsed-refractory and high risk neuroblastoma. Expert opinion: Several novel molecules have been developed and are currently under investigation for the treatment of NB. The trend of novel targeted agents is one towards individualized, tailored therapy, based on the molecular and biological differences that characterize tumors that seem similar based solely on histological analysis. The task of developing new molecules is particularly difficult for NB, given the recurrent development of new patterns of drug resistance. However, even if current research is focused towards identifying the best treatments for each children and young adult with a NB defined disease, a deeper knowledge of the molecular biology and genetics is needed.

  17. Kinetic and spectroscopic investigation of Co{sup II}, Ni{sup II}, and N-oxalylglycine inhibition of the Fe{sup II}/{alpha}-ketoglutarate dioxygenase, TauD

    SciTech Connect

    Kalliri, Efthalia; Grzyska, Piotr K.; Hausinger, Robert P. . E-mail: hausinge@msu.edu

    2005-12-09

    Co{sup II}, Ni{sup II}, and N-oxalylglycine (NOG) are well-known inhibitors of Fe{sup II}/{alpha}-ketoglutarate ({alpha}KG)-dependent hydroxylases, but few studies describe their kinetics and no spectroscopic investigations have been reported. Using taurine/{alpha}KG dioxygenase (TauD) as a paradigm for this enzyme family, time-dependent inhibition assays showed that Co{sup II} and Ni{sup II} follow slow-binding inhibition kinetics. Whereas Ni{sup II}-substituted TauD was non-chromophoric, spectroscopic studies of the Co{sup II}-substituted enzyme revealed a six-coordinate site (protein alone or with {alpha}KG) that became five-coordinate upon taurine addition. The Co{sup II} spectrum was not perturbed by a series of anions or oxidants, suggesting the Co{sup II} is inaccessible and could be used to stabilize the protein. NOG competed weakly (K {sub i} {approx} 290 {mu}M) with {alpha}KG for binding to TauD, with the increased electron density of NOG yielding electronic transitions for NOG-Fe{sup II}-TauD and taurine-NOG-Fe{sup II}-TauD at 380 nm ({epsilon} {sub 38} 90-105 M{sup -1} cm{sup -1}). The spectra of the NOG-bound TauD species did not change significantly upon oxygen exposure, arguing against the formation of an oxygen-bound state mimicking an early intermediate in catalysis.

  18. Topological and functional relationship of subunits F1-gamma and F0I-PVP(b) in the mitochondrial H+-ATP synthase.

    PubMed

    Gaballo, A; Zanotti, F; Solimeo, A; Papa, S

    1998-12-15

    Diamide treatment of the F0F1-ATP synthase in "inside out" submitochondrial particles (ESMP) in the absence of a respiratory Delta mu H+ as well as of isolated Fo reconstituted with F1 or F1-gamma subunit results in direct disulfide cross-linking between cysteine 197 in the carboxy-terminal region of the F0I-PVP(b) subunit and cysteine 91 at the carboxyl end of a small alpha-helix of subunit F1-gamma, both located in the stalk. The F0I-PVP(b) and F1-gamma cross-linking cause dramatic enhancement of oligomycin-sensitive decay of Delta mu H+. In ESMP and MgATP particles the cross-linking is accompanied by decoupling of respiratory ATP synthesis. These effects are consistent with the view that F0I-PVP(b) and F1-gamma are components of the stator and rotor of the proposed rotary motor, respectively. The fact that the carboxy-terminal region of F0I-PVP(b) and the short alpha-helix of F1-gamma can form a direct disulfide bridge shows that these two protein domains are, at least in the resting state of the enzyme, in direct contact. In isolated F0, diamide also induces cross-linking of OSCP with another subunit of F0, but this has no significant effect on proton conduction. When ESMP are treated with diamide in the presence of Delta mu H+ generated by respiration, neither cross-linking between F0I-PVP(b) and F1-gamma subunits nor the associated effects on proton conduction and ATP synthesis is observed. Cross-linking is restored in respiring ESMP by Delta mu H+ collapsing agents as well as by DCCD or oligomycin. These observations indicate that the torque generated by Delta mu H+ decay through Fo induces a relative motion and/or a separation of the F0I-PVP(b) subunit and F1-gamma which places the single cysteine residues, present in each of the two subunits, at a distance at which they cannot be engaged in disulfide bridging.

  19. Possible Involvement of F1F0-ATP synthase and Intracellular ATP in Keratinocyte Differentiation in normal skin and skin lesions

    PubMed Central

    Xiaoyun, Xie; Chaofei, Han; Weiqi, Zeng; Chen, Chen; Lixia, Lu; Queping, Liu; Cong, Peng; Shuang, Zhao; Juan, Su; Xiang, Chen

    2017-01-01

    The F1F0-ATP synthase, an enzyme complex, is mainly located on the mitochondrial inner membrane or sometimes cytomembrane to generate or hydrolyze ATP, play a role in cell proliferation. This study focused on the role of F1F0-ATP synthase in keratinocyte differentiation, and its relationship with intracellular and extracellular ATP (InATP and ExATP). The F1F0-ATP synthase β subunit (ATP5B) expression in various skin tissues and confluence-dependent HaCaT differentiation models was detected. ATP5B expression increased with keratinocyte and HaCaT cell differentiation in normal skin, some epidermis hyper-proliferative diseases, squamous cell carcinoma, and the HaCaT cell differentiation model. The impact of InATP and ExATP content on HaCaT differentiation was reflected by the expression of the differentiation marker involucrin. Inhibition of F1F0-ATP synthase blocked HaCaT cell differentiation, which was associated with a decrease of InATP content, but not with changes of ExATP. Our results revealed that F1F0-ATP synthase expression is associated with the process of keratinocyte differentiation which may possibly be related to InATP synthesis. PMID:28209970

  20. Excessive ATP hydrolysis in ischemic myocardium by mitochondrial F1F0-ATPase: effect of selective pharmacological inhibition of mitochondrial ATPase hydrolase activity.

    PubMed

    Grover, Gary J; Atwal, Karnail S; Sleph, Paul G; Wang, Feng-Li; Monshizadegan, Hossain; Monticello, Thomas; Green, David W

    2004-10-01

    Mitochondrial F(1)F(0)-ATPase normally synthesizes ATP in the heart, but under ischemic conditions this enzyme paradoxically causes ATP hydrolysis. Nonselective inhibitors of this enzyme (aurovertin, oligomycin) inhibit ATP synthesis in normal tissue but also inhibit ATP hydrolysis in ischemic myocardium. We characterized the profile of aurovertin and oligomycin in ischemic and nonischemic rat myocardium and compared this with the profile of BMS-199264, which only inhibits F(1)F(0)-ATP hydrolase activity. In isolated rat hearts, aurovertin (1-10 microM) and oligomycin (10 microM), at concentrations inhibiting ATPase activity, reduced ATP concentration and contractile function in the nonischemic heart but significantly reduced the rate of ATP depletion during ischemia. They also inhibited recovery of reperfusion ATP and contractile function, consistent with nonselective F(1)F(0)-ATPase inhibitory activity, which suggests that upon reperfusion, the hydrolase activity switches back to ATP synthesis. BMS-199264 inhibits F(1)F(0) hydrolase activity in submitochondrial particles with no effect on ATP synthase activity. BMS-199264 (1-10 microM) conserved ATP in rat hearts during ischemia while having no effect on preischemic contractile function or ATP concentration. Reperfusion ATP levels were replenished faster and necrosis was reduced by BMS-199264. ATP hydrolase activity ex vivo was selectively inhibited by BMS-199264. Therefore, excessive ATP hydrolysis by F(1)F(0)-ATPase contributes to the decline in cardiac energy reserve during ischemia and selective inhibition of ATP hydrolase activity can protect ischemic myocardium.

  1. Investigation on the interaction of newly designed potential antibacterial Zn(II) complexes with CT-DNA and HSA.

    PubMed

    Mansouri-Torshizi, Hassan; Khosravi, Fatemeh; Ghahghaei, Arezou; Shahraki, Somaye; Zareian-Jahromi, Sareh

    2017-08-22

    Two Zn(II) complexes of formula [Zn(bpy)(Gly)]NO3 (I) and [Zn(phen)(Gly)]NO3 (II) (where bpy = 2,2'-bipyridine, phen = 1,10-phenanthroline and Gly = glycine) were synthesized and characterized by elemental analysis, molar conductance measurements, UV-vis, FT-IR, and (1)H NMR spectra. The interaction ability of these complexes with calf thymus DNA was monitored using spectroscopic methods, including UV-vis absorption spectroscopy, ethidium bromide displacement, Fourier transform infrared, and electrophoretic mobility assay. Further, the human serum albumin interactions of complexes I and II were investigated using UV-vis absorption spectroscopy, fluorescence quenching, circular dichroism, and Fourier transform infrared. The results obtained from these analyses indicated that both complexes interact effectively with CT-DNA and HSA. The binding constant (Kb), the Stern-Volmer constant (Ksv), and the number of binding sites (n) at different temperatures were determined for CT-DNA and HSA. Also, the negative ΔH° and ΔS° values showed that both hydrogen bonds and van der Waals forces played major roles in the association of CT-DNA-Zn(II) and HSA-Zn(II) complex formation. The displacement experiments suggested that Zn(II)-complexes primarily bound to Sudlow's site II of HSA. The distance between the donor (HSA) and the acceptor (Zn(II) complexes) was estimated on the basis of the Forster resonance energy transfer (FRET) and the alteration of HSA secondary structure induced by the compounds were confirmed by FT-IR spectroscopy. The complexes follow the binding affinity order of I > II with DNA and II > I with HSA. Finally, Antibacterial activity of complexes I and II have been screened against gram positive and gram negative bacteria.

  2. Organic derivatives of tin (II/IV): Investigation of their structure

    NASA Astrophysics Data System (ADS)

    Szirtes, L.; Megyeri, J.; Kuzmann, E.; Beck, A.

    2011-07-01

    The structures of tin(II)-oxalate, tin(IV)Na-EDTA and tin(IV)Na 8-inositol hexaphosphate were investigated using XRD analysis. Samples were identified using the Mössbauer study, thermal analysis and FTIR spectrometry. The Mössbauer study determined two different oxidation states of tin atoms, and consequently two different tin surroundings in the end products. The tin oxalate was found to be orthorhombic with space group Pnma, a=9.2066(3) Å, b=9.7590(1) Å, c=13.1848(5) Å, V=1184.62 Å 3 and Z=8. SnNa-EDTA was found to be monoclinic with space group P2 1/c 1, a=10.7544(3) Å, b=10.1455(3) Å, c=16.5130(6) Å, β=98.59(2)°, V=1781.50(4) Å 3 and Z=4. Sn(C 6H 6Na 8O 24P 6) was found to be amorphous.

  3. Carbonic Anhydrase Activators. Part 191 Spectroscopic and Kinetic Investigations for the Interaction of Isozymes I and II With Primary Amines

    PubMed Central

    Briganti, Fabrizio; Scozzafava, Andrea

    1997-01-01

    The interactions of Zn(II)- and Co(II)-substituted carbonic anhydrase (CA) isozymes I and II with amine type activators such as histamine, serotonin, phenetylamine dopamine and benzylhydrazine have been investigated kinetically, and spectroscopically. All of such activators are of the non-competitive type towards CO2 hydration and 4-nitrophenylacetate hydrolysis for both human isozymes (HCA I and HCA II). The electronic spectra of the adducts of Co(II)CA with amine activators are similar to the spectrum of the previously reported Co(II)CAII-phenol adduct, the only known competitive inhibitor towards CO2 hydration, where the phenol molecule binds into the hydrophobic pocket of the active site. This is a direct spectroscopic evidence that the activator molecules bind within the active site, but not directly to the metal ion. Recent X-ray crystallographic data for the adduct of HCA II with histamine show that the activator molecule is bound at the entrance of the active site cavity, near to residues His 64, Asn 62 and Gln 92, where actively aids in shuttling protons between the active site and the environment. Similar arrangements probably occur for the other activators reported in the present paper. PMID:18475791

  4. Investigation of II-VI Semiconductor Quantum Dots for Sensitized Solar Cell Applications

    NASA Astrophysics Data System (ADS)

    Horoz, Sabit

    Semiconductor nanocrystals, also referred to as quantum dots (QDs) which have advantages of low-cost, photostability, high molar extinction coefficients and size-dependent optical properties, have been the focus of great scientific and technological efforts in solar cells development. Due to the multi-electron generation effect, the theoretical maximum efficiency of quantum dots sensitized solar cells (QDSSCs) is much higher than that of dye sensitized solar cells (DSSCs). Thus QDSSCs have a clear potential to overtake the efficiency of other kinds of solar cells. Doped semiconductor QDs can not only retain nearly all advantages of intrinsic QDs, but also have additional absorption bands for improved efficiency. This approach is particularly important for wide band gap semiconductors, for example, zinc based QDs. Zinc based are desirable candidates as they are inexpensive, earth abundant and nontoxic. When doped, they can cover a broad range of visible spectrum. In my project, I aim at developing novel methods for the preparation of II-VI QDs and investigating the effects of doping on the properties and performances of QDSSCs. Cadmium selenide (CdSe), manganese doped cadmium selenide (Mn:CdSe), and manganese doped zinc sulfide (Mn:ZnS) QDs have been synthesized by laser ablation in water. The structural and luminescent properties of the QDs have been investigated. In addition, QDSSC performances of the samples have been measured using nanowire electrode made of ZnO and Zn2SnO 4. I have also successfully synthesized europium doped zinc sulfide (Eu:ZnS) and manganese doped cadmium sulfide (Mn:CdS) nanoparticles by wet chemical method, and analyzed structural, optical, and magnetic properties as well as the device performance of the nanoparticles.

  5. INVESTIGATING THE DEAROMATIVE REARRANGEMENT OF BIARYL PHOSPHINE-LIGATED PD(II) COMPLEXES

    PubMed Central

    Milner, Phillip J.; Maimone, Thomas J.; Su, Mingjuan; Chen, Jiahao; Müller, Peter; Buchwald, Stephen L.

    2012-01-01

    A series of monoligated L•PdII(Ar)X complexes (L = dialkyl biarylphosphine) have been prepared and studied in an effort to better understand an unusual dearomative rearrangement previously documented in these systems. Experimental and theoretical evidence suggest a concerted process involving the unprecedented PdII-mediated insertion of an aryl group into an unactivated arene. PMID:23153301

  6. Two-band superconductivity in LaFeAsO0.89F0.11 at very high magnetic fields.

    PubMed

    Hunte, F; Jaroszynski, J; Gurevich, A; Larbalestier, D C; Jin, R; Sefat, A S; McGuire, M A; Sales, B C; Christen, D K; Mandrus, D

    2008-06-12

    The recent synthesis of the superconductor LaFeAsO(0.89)F(0.11) with transition temperature T(c) approximately 26 K (refs 1-4) has been quickly followed by reports of even higher transition temperatures in related compounds: 41 K in CeFeAsO(0.84)F(0.16) (ref. 5), 43 K in SmFeAsO(0.9)F(0.1) (ref. 6), and 52 K in NdFeAsO(0.89)F(0.11) and PrFeAsO(0.89)F(0.11) (refs 7, 8). These discoveries have generated much interest in the mechanisms and manifestations of unconventional superconductivity in the family of doped quaternary layered oxypnictides LnOTMPn (Ln: La, Pr, Ce, Sm; TM: Mn, Fe, Co, Ni; Pn: P, As), because many features of these materials set them apart from other known superconductors. Here we report resistance measurements of LaFeAsO(0.89)F(0.11) at high magnetic fields, up to 45 T, that show a remarkable enhancement of the upper critical field B(c2) compared to values expected from the slopes dB(c2)/dT approximately 2 T K(-1) near T(c), particularly at low temperatures where the deduced B(c2)(0) approximately 63-65 T exceeds the paramagnetic limit. We argue that oxypnictides represent a new class of high-field superconductors with B(c2) values surpassing those of Nb(3)Sn, MgB(2) and the Chevrel phases, and perhaps exceeding the 100 T magnetic field benchmark of the high-T(c) copper oxides.

  7. Investigation of the Geoeffectiveness of CMEs Associated with IP Type II Radio Bursts

    NASA Astrophysics Data System (ADS)

    Vasanth, V.; Chen, Y.; Kong, X. L.; Wang, B.

    2015-06-01

    We perform a statistical analysis of the geoeffectiveness of coronal mass ejections (CMEs) that are associated with interplanetary (IP) type II bursts in Solar Cycle 23 during the period 1997 - 2008. About 47 % (109 out of 232) of IP type II bursts are found to be associated with geomagnetic storms. Of these 47 %, 27 % are associated with moderate, 14 % with intense, and 6 % with severe geomagnetic storms. We find that the IP type II bursts and their corresponding end frequencies can be used as indicators of CME geoeffectiveness: the lower the type II burst end frequency, the higher the possibility of having a stronger storm. In addition, we show that various combinations of CME remote-sensing and IP type II parameters can be used to improve geomagnetic storm forecasting.

  8. Vibrational dynamics of plant light-harvesting complex LHC II investigated by quasi- and inelastic neutron scattering

    NASA Astrophysics Data System (ADS)

    Golub, Maksym; Irrgang, Klaus-Dieter; Rusevich, Leonid; Pieper, Jörg

    2015-01-01

    Vibrational dynamics of the light-harvesting complex II (LHC II) from spinach was investigated by quasi- and inelastic neutron scattering (QENS and INS) at three different temperatures of 80, 160, and 285 K. QENS/INS spectra of solubilised LHC II and of the corresponding buffer solution were obtained separately and exhibit characteristic inelastic features. After subtraction of the buffer contribution, the INS spectrum of LHC II reveals a distinct Boson peak at ˜ 2.5 meV at 80 K that shifts towards lower energies if the temperature is increased to 285 K. This effect is interpreted in terms of a "softening" of the protein matrix along with the dynamical transition at ˜ 240 K. Our findings indicate that INS is a valuable method to obtain the density of vibrational states not only at cryogenic, but also at physiological temperatures.

  9. Dynamic investigation of DNA bending and wrapping by type II topoisomerases

    NASA Astrophysics Data System (ADS)

    Shao, Qing; Finzi, Laura; Dunlap, David

    2009-11-01

    Type II topoisomerases catalyze DNA decatenation and unwinding which is crucial for cell division, and therefore type II topoisomerases are some of the main targets of anti-cancer drugs. A recent crystal structure shows that, during the catalytic cycle, a yeast type II topoimerase can bend a 10 base pair DNA segment by up to 150 degrees. Bacterial gyrase, another type II topoisomerase, can wrap DNA into a tight 180 degree turn. Bending a stiff polymer like DNA requires considerable energy and could represent the rate limiting step in the catalytic (topological) cycle. Using modified deoxyribonucleotides in PCR reactions, stiffer DNA fragments have been produced and used as substrates for topoisomerase II-mediated relaxation of plectonemes introduced in single molecules using magnetic tweezers. The wrapping ability of gyrase decreases for diamino-purine-substituted DNA in which every base pair has three hydrogen-bonds. The overall rate of relaxation of plectonemes by recombinant human topoisomerase II alpha also decreases. These results reveal the dynamic properties of DNA bending and wrapping by type II topisomerases and suggest that A:T base pair melting is a rate determining step for bending and wrapping.

  10. Spectroscopic investigation of bis-appended 1,2,3-triazole probe for the detection of Cu(II) ion

    NASA Astrophysics Data System (ADS)

    Ghosh, Debanjana; Rhodes, Shannon; Winder, Domonique; Atkinson, Austin; Gibson, Jaclyn; Ming, Weihua; Padgett, Clifford; Landge, Shainaz; Aiken, Karelle

    2017-04-01

    A novel bis-1,4-disubstituted-1,2,3-triazole chemosensor, accessed with "Click Chemistry", was probed for its recognition of metal ions. The interaction of the sensor with various cation analytes was investigated by 1H-NMR, UV-Vis absorption and fluorescence spectroscopy. The bis-triazole is selective for Cu(II) with a detection limit in the micromolar concentration range and a clear to yellow colorimetric response that is exclusive to that ion is observed. The stoichiometry of probe to Cu(II), 2:1, was determined with Job's plots based on titration studies using UV-absorption and 1H-NMR spectroscopy. Computational and spectroscopic investigations revealed that the sensor binds to Cu(II) via its triazole units.

  11. Transepithelial corneal collagen crosslinking for keratoconus: qualitative investigation by in vivo HRT II confocal analysis.

    PubMed

    Caporossi, Aldo; Mazzotta, Cosimo; Baiocchi, Stefano; Caporossi, Tomaso; Paradiso, Anna Lucia

    2012-01-01

    This was a qualitative investigation of corneal microstructural modifications in keratoconic patients undergoing experimental transepithelial crosslinking (TE CXL). Ten patients with keratoconus intolerant to gas-permeable rigid contact lenses were enrolled. Corneal thickness was in the range 350-390 µm at the thinnest point measured by Visante AC optical coherence tomography system (Zeiss, Jena, Germany). All patients underwent TE CXL with 0.1% riboflavin-15% dextran solution supplemented with TRIS plus sodium EDTA (Ricrolin TE, Sooft Italia) according to Siena protocol. In vivo Heidelberg retinal tomograph II laser scanning confocal analysis (Rostock Cornea Module, Heidelberg, Germany) was performed with the following follow-up: preoperative and postoperative assessments at 1, 3, and 6 months. The following morphologic parameters were evaluated: epithelium, subepithelial, and anterior stroma nerve plexi, keratocytes apoptosis, stromal changes, and the endothelium. After TE CXL, epithelial cells showed apoptosis, with mosaic alterations gradually disappearing. Keratocytes apoptosis was variable, superficial, and uneven, with a maximum depth of penetration at about 140 µm, measured from the surface of epithelium. Treatment respected subepithelial and stromal nerves that did not disappear. No variation in cell count or endothelial mosaic was observed. In vivo confocal analysis of corneal modifications induced by TE CXL showed a limited apoptotic affect of this treatment, about one-third of classic epi-off crosslinking procedure. The TE CXL respected sub-basal and anterior stroma nerve fibers, resulting safe for corneal endothelium. According to limited penetration, its mid- to long-term efficacy needs to be determined in different clinical settings related to patient age and keratoconus progression.

  12. A spectroscopic investigation of the interaction between c-MYC DNA and tetrapyridinoporphyrazinatozinc(II).

    PubMed

    Hassani, Leila; Fazeli, Zahra; Safaei, Elham; Rastegar, Hossein; Akbari, Minoo

    2014-06-01

    The c-MYC gene plays an important role in the regulation of cell proliferation and growth and it is overexpressed in a wide variety of human cancers. Around 90% of c-MYC transcription is controlled by the nuclease-hypersensitive element III1 (NHE III1), whose 27-nt purine-rich strand has the ability to form a G-quadruplex structure under physiological conditions. Therefore, c-MYC DNA is an attractive target for drug design, especially for cancer chemotherapy. Here, the interaction of water-soluble tetrapyridinoporphyrazinatozinc(II) with 27-nt G-rich strand (G/c-MYC), its equimolar mixture with the complementary sequence (GC/c-MYC) and related C-rich oligonucleotide (C/c-MYC) is investigated. Circular dichroism (CD) measurements of the G-rich 27-mer oligonucleotide in 150 mM KCl, pH 7 demonstrate a spectral signature consistent with parallel G-quadruplex DNA. Furthermore, the CD spectrum of the GC rich oligonucleotide shows characteristics of both duplex and quadruplex structures. Absorption spectroscopy implies that the complex binding of G/c-MYC and GC/c-MYC is a two-step process; in the first step, a very small red shift and hypochromicity and in the second step, a large red shift and hyperchromicity are observed in the Q band. Emission spectra of zinc porphyrazine are quenched upon addition of three types of DNA. According to the results of spectroscopy, it can be concluded the dominant binding mode is probably, outside binding and end stacking.

  13. Fort Holabird Defense Investigative Service (DIS), Base Realignment and Closure (BRAC) Cleanup Plan (BCP), Version II

    DTIC Science & Technology

    1998-12-01

    Volatile Organic Compound WWII ................ World War II 0 40 DACA31-94-D-0064 A Fort Holabird DIS Base Realignment and Closure...was filled in around the time the larger Fort Holabird installation was created during World War I. The Fort Holabird DIS performed security...during World War II (WWII). After WWII, portions of Fort Holabird were reassigned or sold off piece by piece. In 1970 the Defense Department announced

  14. A preliminary investigation of the Topaz II reactor as a lunar surface power supply

    SciTech Connect

    Polansky, G.F.; Houts, M.G.

    1995-12-31

    Reactor power supplies offer many attractive characteristics for lunar surface applications. The Topaz II reactor resulted from an extensive development program in the former Soviet Union. Flight quality reactor units remain from this program and are currently under evaluation in the United States. This paper examines the potential for applying the Topaz II, originally developed to provide spacecraft power, as a lunar surface power supply.

  15. Phase II Investigation at the Former CCC/USDA Grain Storage Facility in Savannah, Missouri

    SciTech Connect

    LaFreniere, Lorraine M.

    2012-05-01

    contamination potentially associated with a number of former CCC/USDA grain storage facilities in Missouri. The site characterization at Savannah is being conducted on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. The investigation is being conducted in phases, so that information obtained and interpretations developed during each incremental stage can be used most effectively to guide subsequent phases of the program. Phase II objectives: Investigate the more detailed characteristics of groundwater flow in the vicinity of the former CCC/USDA facility and the contaminated Morgan and MoDOT private wells; Obtain additional information on the vertical and lateral distribution and concentrations of carbon tetrachloride in groundwater in the vicinity of the former CCC/USDA facility and the contaminated Morgan and MoDOT private wells; Investigate further for possible evidence of carbon tetrachloride in the subsurface (vadose zone) and deeper soils beneath the former CCC/USDA facility, as well as in the vicinity of the contaminated MoDOT private well.

  16. Nickel(II), copper(II) and zinc(II) metallo-intercalators: structural details of the DNA-binding by a combined experimental and computational investigation.

    PubMed

    Lauria, Antonino; Bonsignore, Riccardo; Terenzi, Alessio; Spinello, Angelo; Giannici, Francesco; Longo, Alessandro; Almerico, Anna Maria; Barone, Giampaolo

    2014-04-28

    We present a thorough characterization of the interaction of novel nickel(II) (1), copper(II) (2) and zinc(II) (3) Schiff base complexes with native calf thymus DNA (ct-DNA), in buffered aqueous solution at pH 7.5. UV-vis absorption, circular dichroism (CD) and viscometry titrations provided clear evidence of the intercalative mechanism of the three square-planar metal complexes, allowing us to determine the intrinsic DNA-binding constants (K(b)), equal to 1.3 × 10(7), 2.9 × 10(6), and 6.2 × 10(5) M(-1) for 1, 2 and 3, respectively. Preferential affinity, of one order of magnitude, toward AT compared to GC base pair sequences was detected by UV-vis absorption titrations of 1 with [poly(dG-dC)]2 and [poly(dA-dT)]2. Structural details of the intercalation site of the three metal complexes within [dodeca(dA-dT)]2 were obtained by molecular dynamics (MD) simulations followed by density functional theory/molecular mechanics (DFT/MM) calculations. The calculations revealed that three major intermolecular interactions contribute to the strong affinity between DNA and the three metal complexes: (1) the electrostatic attraction between the two positively charged triethylammoniummethyl groups of the metal complexes and the negatively charged phosphate groups of the DNA backbone; (2) the intercalation of the naphthalene moiety within the four nitrogen bases of the intercalation site; (3) the metal coordination by exocyclic donor atoms of the bases, specifically the carbonyl oxygen and amine nitrogen atoms. Remarkably, the Gibbs formation free energy calculated for the intercalation complexes of 1, 2 and 3 with [dodeca(dA-dT)]2 in the implicit water solution is in agreement with the experimental Gibbs free energy values obtained from the DNA-binding constants as ΔG° = -RT ln(K(b)). In particular, the DNA-binding affinity trend, 1 > 2 > 3, is reproduced. Finally, the first shell coordination distances calculated for the intercalation complex 3/[dodeca(dA-dT)]2 are in

  17. The adsorption behavior and mechanism investigation of Pb(II) removal by flocculation using microbial flocculant GA1.

    PubMed

    Feng, Jing; Yang, Zhaohui; Zeng, Guangming; Huang, Jing; Xu, Haiyin; Zhang, Yuanyuan; Wei, Shumei; Wang, Like

    2013-11-01

    In this work, microbial flocculant GA1 (MBFGA1) was used to remove Pb(II) ions from aqueous solution. A series of experimental parameters including initial pH, MBFGA1 dose, temperature and initial calcium ions concentration on Pb(II) uptake was evaluated. Meanwhile, the flocculation mechanism of MBFGA1 was investigated. The removal efficiency of Pb(II) reached up to 99.85% when MBFGA1 was added in two stages, separately. The results indicated that Pb(II) adsorption could be described by the Langmuir adsorption model, and being the monolayer capacity negatively affected with an increase in temperature. The adsorption process could be described by pseudo-second-order kinetic model. Fourier transform-infrared spectra and environmental scanning electron microscope analysis indicated that MBFGA1 had a large number of functional groups, which had strong capacity for removing Pb(II). The main mechanisms of Pb(II) removal by MBFGA1 could be charge neutralization and adsorption bridging.

  18. On the role of horizontal wind shears in the generation of F0.5 layers over the dip equatorial location of Thiruvananthapuram: A numerical simulation study

    NASA Astrophysics Data System (ADS)

    Mridula, N.; Pant, Tarun Kumar

    2017-03-01

    A numerical simulation is carried out to estimate the rate of convergence of ionization required to produce a F0.5 layer with peak plasma frequency (foF0.5) of 3.2 MHz from three different background layer densities, over Thiruvananthapuram (8.5°N; 77°E; dip latitude 0.5°N), a dip equatorial station in India. Further the simulation study is extended to understand the convergences required by considering the seasonal mean peak F0.5 layer frequencies also. One possible mechanism by which this convergence can be produced is by a horizontal shear in the meridional wind. The corresponding shears required to generate the layer with the above convergence conditions are estimated. It is found that gravity waves are capable of generating wind shears, leading to the pooling of ionization and the generation of the layer over the dip equator. A meridional wind with the gravity wave induced wind shear is numerically estimated. Finally, the short scale gravity waves of periods around 3-23 min have been inferred to be more efficient in generating the wind shear when compared to large scale horizontal waves leading to the generation of F0.5 layer.

  19. Pitch (F0) and formant profiles of human vowels and vowel-like baboon grunts: The role of vocalizer body size and voice-acoustic allometry

    NASA Astrophysics Data System (ADS)

    Rendall, Drew; Kollias, Sophie; Ney, Christina; Lloyd, Peter

    2005-02-01

    Key voice features-fundamental frequency (F0) and formant frequencies-can vary extensively between individuals. Much of the variation can be traced to differences in the size of the larynx and vocal-tract cavities, but whether these differences in turn simply reflect differences in speaker body size (i.e., neutral vocal allometry) remains unclear. Quantitative analyses were therefore undertaken to test the relationship between speaker body size and voice F0 and formant frequencies for human vowels. To test the taxonomic generality of the relationships, the same analyses were conducted on the vowel-like grunts of baboons, whose phylogenetic proximity to humans and similar vocal production biology and voice acoustic patterns recommend them for such comparative research. For adults of both species, males were larger than females and had lower mean voice F0 and formant frequencies. However, beyond this, F0 variation did not track body-size variation between the sexes in either species, nor within sexes in humans. In humans, formant variation correlated significantly with speaker height but only in males and not in females. Implications for general vocal allometry are discussed as are implications for speech origins theories, and challenges to them, related to laryngeal position and vocal tract length. .

  20. Vacuolar ATPases, like F1,F0-ATPases, show a strong dependence of the reaction velocity on the binding of more than one ATP per enzyme.

    PubMed Central

    Kasho, V N; Boyer, P D

    1989-01-01

    Recent studies with vacuolar ATPases have shown that multiple copies catalytic subunits are present and that these have definite sequence homology with catalytic subunits of the F1,F0-ATPases. Experiments are reported that assess whether the vacuolar ATPases may have the unusual catalytic cooperativity with sequential catalytic site participation as in the binding change mechanism for the F1,F0-ATPases. The extent of reversal of bound ATP hydrolysis to bound ADP and Pi as medium ATP concentration was lowered was determined by 18O-exchange measurements for yeast and neurospora vacuolar ATPases. The results show a pronounced increase in the extent of water oxygen incorporation into the Pi formed as ATP concentration is decreased to the micromolar range. The F1,F0-ATPase from neurospora mitochondria showed an even more pronounced modulation, similar to that of other F1-type ATPases. The vacuolar ATPases thus appear to have a catalytic mechanism quite analogous to that of the F1,F0-ATPases. PMID:2530585

  1. The roles of voice onset time and F0 in stop consonant voicing perception: Effects of masking noise and low-pass filtering

    PubMed Central

    Winn, Matthew B.; Chatterjee, Monita; Idsardi, William J.

    2013-01-01

    Purpose The contributions of voice onset time (VOT) and fundamental frequency (F0) were evaluated for the perception of voicing in syllable-initial stop consonants in words that were low-pass filtered and/or masked by speech-shaped noise. It was expected that listeners would rely less on VOT and more on F0 in these degraded conditions. Method Twenty young normal-hearing listeners identified modified natural speech tokens that varied by VOT and F0 in several conditions of low-pass filtering and masking noise. Stimuli included /b/-/p/ and /d/-/t/ continua that were presented in separate blocks. Identification results were modeled using mixed-effects logistic regression. Results When speech was filtered and/or masked by noise, listeners’ voicing perceptions were driven less by VOT and more by F0. Speech-shaped masking noise exerted greater effects on the /b/-/p/ contrast, while low-pass filtering exerted greater effects on the /d/-/t/ contrast, consistent with the acoustics of these contrasts. Conclusion Listeners can adjust their use of acoustic-phonetic cues in a dynamic way that is appropriate for challenging listening conditions; cues that are less influential in ideal conditions can gain priority in challenging conditions. PMID:23785185

  2. Interference phenomena in the decay Ds+→η π0π+ induced by the a00(980 )-f0(980 ) mixing

    NASA Astrophysics Data System (ADS)

    Achasov, N. N.; Shestakov, G. N.

    2017-08-01

    Using the data on the decay Ds+→f0(980 )π+→K+K-π+ , we estimate the amplitude of the process Ds+→[f0(980 )→(K+K-+K0K¯0)→a00(980 )] π+→η π0π+, caused by the mixing of a00(980 ) and f0(980 ) resonances that breaks the isotopic invariance due to the K+ and K0 meson mass difference. Effects of the interference of this amplitude with the amplitudes of the main mechanisms responsible for the decay Ds+→η π0π+ are analyzed. As such mechanisms, we examine the transition Ds+→η ρ+→η π0π+, which is observed in experiment, and the possible transition Ds+→(a00(980 )π++a0+(980 )π0) →η π0π+. It is shown that the rapidly varying phase of the a00(980 )-f0(980 ) transition amplitude strongly influences the interference curves.

  3. Interacting cytoplasmic loops of subunits a and c of Escherichia coli F1F0 ATP synthase gate H+ transport to the cytoplasm.

    PubMed

    Steed, P Ryan; Kraft, Kaitlin A; Fillingame, Robert H

    2014-11-25

    H(+)-transporting F1F0 ATP synthase catalyzes the synthesis of ATP via coupled rotary motors within F0 and F1. H(+) transport at the subunit a-c interface in transmembranous F0 drives rotation of a cylindrical c10 oligomer within the membrane, which is coupled to rotation of subunit γ within the α3β3 sector of F1 to mechanically drive ATP synthesis. F1F0 functions in a reversible manner, with ATP hydrolysis driving H(+) transport. ATP-driven H(+) transport in a select group of cysteine mutants in subunits a and c is inhibited after chelation of Ag(+) and/or Cd(+2) with the substituted sulfhydryl groups. The H(+) transport pathway mapped via these Ag(+)(Cd(+2))-sensitive Cys extends from the transmembrane helices (TMHs) of subunits a and c into cytoplasmic loops connecting the TMHs, suggesting these loop regions could be involved in gating H(+) release to the cytoplasm. Here, using select loop-region Cys from the single cytoplasmic loop of subunit c and multiple cytoplasmic loops of subunit a, we show that Cd(+2) directly inhibits passive H(+) transport mediated by F0 reconstituted in liposomes. Further, in extensions of previous studies, we show that the regions mediating passive H(+) transport can be cross-linked to each other. We conclude that the loop-regions in subunits a and c that are implicated in H(+) transport likely interact in a single structural domain, which then functions in gating H(+) release to the cytoplasm.

  4. Huge critical current density and tailored superconducting anisotropy in SmFeAsO0.8F0.15 by low-density columnar-defect incorporation

    NASA Astrophysics Data System (ADS)

    Fang, L.; Jia, Y.; Mishra, V.; Chaparro, C.; Vlasko-Vlasov, V. K.; Koshelev, A. E.; Welp, U.; Crabtree, G. W.; Zhu, S.; Zhigadlo, N. D.; Katrych, S.; Karpinski, J.; Kwok, W. K.

    2013-11-01

    Iron-based superconductors could be useful for electricity distribution and superconducting magnet applications because of their relatively high critical current densities and upper critical fields. SmFeAsO0.8F0.15 is of particular interest as it has the highest transition temperature among these materials. Here we show that by introducing a low density of correlated nano-scale defects into this material by heavy-ion irradiation, we can increase its critical current density to up to 2 × 107 A cm-2 at 5 K—the highest ever reported for an iron-based superconductor—without reducing its critical temperature of 50 K. We also observe a notable reduction in the thermodynamic superconducting anisotropy, from 8 to 4 upon irradiation. We develop a model based on anisotropic electron scattering that predicts that the superconducting anisotropy can be tailored via correlated defects in semimetallic, fully gapped type II superconductors.

  5. Phase II clinical trials on Investigational drugs for the Treatment of Pancreatic Cancers

    PubMed Central

    Kim, Edward J.; Semrad, Thomas J.; Bold, Richard J.

    2015-01-01

    Introduction Despite some recent advances in treatment options, pancreatic cancer remains a devastating disease with poor outcomes. In a trend contrary to most malignancies, both incidence and mortality continue to rise due to pancreatic cancer. The majority of patients present with advanced disease and there are no treatment options for this stage that have demonstrated a median survival greater than 1 year. As the penultimate step prior to phase III studies involving hundreds of patients, phase II clinical trials provide an early opportunity to evaluate the efficacy of new treatments that are desperately needed for this disease. Areas Covered This review covers the results of published phase II clinical trials in advanced pancreatic adenocarcinoma published within the past 5 years. The treatment results are framed in the context of the current standards of care and the historic challenge of predicting phase III success from phase II trial results. Expert opinion Promising therapies remain elusive in pancreatic cancer based on recent phase II clinical trial results. Optimization and standardization of clinical trial design in the phase II setting, with consistent incorporation of biomarkers, is needed to more accurately identify promising therapies that warrant phase III evaluation. PMID:25809274

  6. Investigation of intermediates and transition states in the catalytic mechanisms of active site substituted cobalt(II), nickel(II), zinc(II), and cadmium(II) horse liver alcohol dehydrogenase

    SciTech Connect

    Dunn, M.F.; Dietrich, H.; MacGibbon, A.K.H.; Koerber, S.C.; Zeppezauer, M.

    1982-01-12

    Active site substituted Co(II)-, Ni(II)-, and Cd(II)-horse liver alcohol dehydrogenase derivatives are compared to the native Zn(II)-enzyme with respect to the kinetic properties associated with the formation and decay of the intermediate observed in the reaction of the binary E-(NADH) complex with the intense substrate chromophore trans-4-(N,N-dimethylamino) cinnamaldehyde (DACA), lambda/sub max/ 398 nm (H/sub 2/O). All the metal ion subsituted enzymes were found to form intermediates with red-shifted spectra upon reaction with DACA and NADH. The magnitudes of (1) the red shifts, (2) the specific rate constants (k/sub off/) for dissociation of DACA from the intermediate, and (3) the hydride transfer rate constants (k /sub H/) were found to correlate with the expected order of the Lewis acid acidities (assuming tetrahedral coordination); i.e., Co(II) > Ni(II) greater than or equal to Zn(II) >> Cd(II). The k/sub H/ value for the Co(II)-E was found to be 1.4-fold greater than the value of 7.2 s/sup -1/ for Zn(II)-E, while the Cd(II)-E was40-fold lower. It is concluded that the close similarities in kinetic properties exhibited by Co(II)-, Ni(II)-, and Zn(II)-enzymes arise from the close similarities in coordination geometries and Lewis acid strengths which lead to highly similar transition states for the processes of intemediate formation and decay. (JMT)

  7. Investigating the Conditions of the Formation of a Type II Radio Burst on 2014 January 8

    NASA Astrophysics Data System (ADS)

    Su, W.; Cheng, X.; Ding, M. D.; Chen, P. F.; Ning, Z. J.; Ji, H. S.

    2016-10-01

    It is believed that type II radio bursts are generated by shock waves. In order to understand the generation conditions of type II radio bursts, we analyze the physical parameters of a shock front. The type II radio burst we selected was observed by the Siberian Solar Radio Telescope (SSRT) and Learmonth radio station and was associated with a limb coronal mass ejection (CME) occurring on 2014 January 8 observed by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory. The evolution of the CME in the inner corona presents a double-layered structure that propagates outward. We fit the outer layer (OL) of the structure with a partial circle and divide it into seven directions from -45° to 45° with an angular separation of 15°. We measure the OL speed along the seven directions and find that the speed in the direction of -15° with respect to the central direction is the fastest. We use the differential emission measure method to calculate the physical parameters at the OL at the moment when the type II radio burst was initiated, including the temperature (T), emission measure (EM), temperature ratio ({T}d/{T}{{u}}), compression ratio (X), and Alfvén Mach number (M A). We compare the quantities X and M A to those obtained from band-splitting in the radio spectrum, and find that this type II radio burst is generated at a small region of the OL that is located at the sector in the 45° direction. The results suggest that the generation of type II radio bursts (shocks) requires larger values of X and M A rather than simply a higher speed of the disturbance.

  8. Evolution of Overlapping Spreading Centers: A SeaMARC II Investigation

    DTIC Science & Technology

    1990-06-07

    be seen if ACIFIC OCEAN - ,,’- ... . magma actually flows laterally below ’. ’ the ridge axis, but significant evidence 100 A has been found to support... ocean ridges based primarily on SeaMARC II data from our ONR cruise,-3) creation of fin 150 mcontour interval maps for 8°-18°N merging SeaMARC II data...time period. 2) A marked variation in fault-facing direction with spreading rate is observed on the flanks of mid- ocean ridges. On slow and

  9. Investigation of equid paleodiet from Schöningen 13 II-4 through dental wear and isotopic analyses: Archaeological implications.

    PubMed

    Rivals, Florent; Julien, Marie-Anne; Kuitems, Margot; Van Kolfschoten, Thijs; Serangeli, Jordi; Drucker, Dorothée G; Bocherens, Hervé; Conard, Nicholas J

    2015-12-01

    The paleodietary traits of the equid population from Schöningen 13 II-4 were investigated through tooth mesowear and microwear analyses, as well as stable isotopic analyses. The mesowear pattern observed on the upper teeth indicates a low abrasion diet with a significant amount of browse in the diet of the horses. The tooth microwear analysis and the isotopic data confirm that the horses from Schöningen 13 II-4 were mixed feeders, like many populations from other Pleistocene localities in Northern and Eastern Europe. Microwear also provides information on seasonal changes in the diet of the horses and offers the possibility to test hypotheses about the presence of one or several horse populations. Our analysis determined that the assemblage of horse remains from Schöningen 13 II-4 resulted from multiple accumulation events, which took place at different periods of time.

  10. Spectroscopic, Structural, and Kinetic Investigation of the Ultrafast Spin Crossover in an Unusual Cobalt(II) Semiquinonate Radical Complex.

    PubMed

    Rupp, Fabian; Chevalier, Katharina; Graf, Michèle; Schmitz, Markus; Kelm, Harald; Grün, Anneken; Zimmer, Manuel; Gerhards, Markus; van Wüllen, Christoph; Krüger, Hans-Jörg; Diller, Rolf

    2017-02-10

    A comprehensive spectroscopic and structural investigation of [Co(II) (l-N4  tBu2 )(dbsq)][B(p-C6 H4 Cl)4 ] (1, l-N4  tBu2 =N,N'-di-tert-butyl-2,11-diaza[3.3](2,6)pyridinophane, dbsq(1-) =3,5-di-tert-butylsemiquinonate), the first known octahedral complex with a low-spin (ls) Co(II) semiquinonate ground state, is reported. Above 200 K, solids as well as solutions of 1 exhibit thermally induced spin-crossover (SCO) from the ls to the high-spin (hs) Co(II) semiquinonate state instead of the frequently observed valence tautomerism from ls Co(III) catecholate to hs Co(II) semiquinonate. DFT calculations demonstrate that the (closed shell) Co(III) catecholate suffers from a triplet instability leading to the ls Co(II) semiquinonate ground state. The thorough temperature-dependent spectroscopic study of the SCO enables a photophysical investigation. Thus, by selective photoexcitation of the ls fraction of 1 in solution at room temperature, ultrafast conversion to the hs state is observed using femtosecond electronic and IR-vibrational (infrared) transient absorption spectroscopy. The kinetics of the photocycle is described by a stretched exponential with τ=3.3-3.6 ps and β=0.52-0.54, representing an upper limit for the hs-ls relaxation time. This is, to our knowledge, the fastest interconversion ever determined for a SCO complex, and is attributed to the special situation that in 1 a Co(II) complex is coordinated to a π-radical ligand allowing very efficient coupling between the ls and hs spin states. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Quantitative investigation of copper(II) and zinc(II) complexes with S-carboxymethyl-L-cysteine and computer-simulated appraisal of their potential significance in vivo.

    PubMed

    Brumas, V; Venturini, M; Filella, M; Berthon, G

    1989-12-01

    S-carboxymethyl-L-cysteine (SCC) is a mucolytic agent extensively used in the treatment of respiratory tract disorders. Some of the undesirable side effects observed during SCC therapy being reminiscent of symptoms characteristic of copper and zinc imbalances, the objective of this paper was to test the possible interference of SCC with the metabolism of these two metals. Copper(II)- and zinc(II)-SCC complex equilibria have thus been investigated under physiological conditions by means of classical potentiometry combined with computer-assisted calculation techniques. Formation constants derived from these studies have then been used to simulate 1) the potential influence of SCC on the distribution of the above metals in blood plasma and 2) the extent to which gastrointestinal interactions between the drug and each metal ion in turn are likely to affect the bioavailability of each other. The results of these simulations show that 1) plasma therapeutic levels of SCC are not likely to induce dramatic changes in the distributions of copper(II) and zinc(II) low molecular weight fractions, 2) the gastrointestinal distribution of the drug is not affected by standard dietary doses of these metals, and 3) in contrast, therapeutic concentrations of SCC are capable of mobilizing significant fractions of both metals into tissue-diffusible electrically neutral complexes. In conclusion significant depletions of neither copper nor zinc are to be expected from oral administration of SCC. While the drug may to some extent facilitate the excretion of Cu2+ and Zn2+ ions from blood plasma, its gastrointestinal influence is, on the contrary, favorable to a better absorption of these two metals.

  12. Spectroscopic investigation of new water soluble Mn(II)(2) and Mg(II)(2) complexes for the substrate binding models of xylose/glucose isomerases.

    PubMed

    Patra, Ayan; Bera, Manindranath

    2014-01-30

    In methanol, the reaction of stoichiometric amounts of Mn(OAc)(2)·4H(2)O and the ligand H(3)hpnbpda [H(3)hpnbpda=N,N'-bis(2-pyridylmethyl)-2-hydroxy-1,3-propanediamine-N,N'-diacetic acid] in the presence of NaOH, afforded a new water soluble dinuclear manganese(II) complex, [Mn2(hpnbpda)(μ-OAc)] (1). Similarly, the reaction of Mg(OAc)(2)·4H(2)O and the ligand H3hpnbpda in the presence of NaOH, in methanol, yielded a new water soluble dinuclear magnesium(II) complex, [Mg2(hpnbpda)(μ-OAc)(H2O)2] (2). DFT calculations have been performed for the structural optimization of complexes 1 and 2. The DFT optimized structure of complex 1 shows that two manganese(II) centers are in a distorted square pyramidal geometry, whereas the DFT optimized structure of complex 2 reveals that two magnesium(II) centers adopt a six-coordinate distorted octahedral geometry. To understand the mode of substrate binding and the mechanistic details of the active site metals in xylose/glucose isomerases (XGI), we have investigated the binding interactions of biologically important monosaccharides d-glucose and d-xylose with complexes 1 and 2, in aqueous alkaline solution by a combined approach of FTIR, UV-vis, fluorescence, and (13)C NMR spectroscopic techniques. Fluorescence spectra show the binding-induced gradual decrease in emission of complexes 1 and 2 accompanied by a significant blue shift upon increasing the concentration of sugar substrates. The binding modes of d-glucose and d-xylose with complex 2 are indicated by their characteristic coordination induced shift (CIS) values in (13)C NMR spectra for C1 and C2 carbon atoms.

  13. Project PRE-Schooner II. Postshot Geologic and Engineering Properties Investigations

    DTIC Science & Technology

    1967-11-01

    rock medium. 9 1. 5 PROJECT LOCATION AND ACCESSIBILITY The Pre-Schooner II Event was located in Owyhee County of southwestern Idaho. The site is...Radiation Laboratory, Livermore. 11. L. M. Gard and J. W. Hasler; "Geology of Proposed Schooner Site, Bruneau River Area, Owyhee County, Idaho" USGS

  14. Diagnostic Indicators of Codependence: An Investigation Using the MCMI-II.

    ERIC Educational Resources Information Center

    Loughead, Teri A.; Spurlock, Vicki L.; Ting, Yuan-yu

    1998-01-01

    A paucity of empirical research exists concerning codependence. Diagnostic indicators for self-identified codependent individuals (N=37) are examined. Cluster analysis utilizing 22 MCMI-II diagnostic scales created three cluster groups. Participants exhibited a disordered avoidant and self-defeating coping style, accompanied by passive-aggressive,…

  15. Production of f 2(1270) and f 0(975) mesons by photons and hadrons of energy 65 175 GeV

    NASA Astrophysics Data System (ADS)

    Apsimon, R. J.; Atkinson, M.; Baake, M.; Bagdasarian, L. S.; Barberis, D.; Brodbeck, T. J.; Brook, N.; Charity, T.; Clegg, A. B.; Coyle, P.; Danaher, S.; Danagulian, S.; Davenport, M.; Dickinson, B.; Diekmann, B.; Donnachie, A.; Doyle, A. T.; Eades, J.; Ellison, R. J.; Fiedler, F.; Flower, P. S.; Foster, J. M.; Galbraith, W.; Galumian, P. I.; Gapp, C.; Gebert, F.; Hallewell, G.; Heinloth, K.; Henderson, R. C. W.; Hickman, M. T.; Hoeger, K. C.; Hofmann, R. P.; Holzkamp, A.; Holzkamp, S.; Hughes-Jones, R. E.; Ibbotson, M.; Jacob, H. P.; Joseph, D.; Keemer, N. R.; Kingler, J.; Körsgen, G.; Kolya, S. D.; Lafferty, G. D.; McCann, H.; McClatchey, R.; McManus, C.; Mercer, D.; Morris, J. A. G.; Morris, J. V.; Newton, D.; O'Connor, A.; Oedingen, R.; Oganesian, A. G.; Ottewell, P. J.; Paterson, C. N.; Paul, E.; Reid, D.; Rotscheidt, H.; Sharp, P. H.; Söldner-Rembold, S.; Thacker, N. A.; Thompson, L.; Thompson, R. J.; Waterhouse, J.; Weigend, A. S.; Wilson, G. W.

    1992-06-01

    Measurements are reported of inclusive f 2(1270) and f 0(975) production in γp, π± p and K ± p collisions at photon beam energies of 65 to 175 GeV and hadron beam energies of 80 and 140 GeV. The f 2 and f 0 mesons were found at masses of 1.250 GeV and 0.961 GeV respectively. Inclusive f 2 production at low x F was found to have a similar p T dependence for each beam type, whereas an additional pion-exchange contribution was found for production by pions at high x F. Cross sections are compared with those for ρ0 production and give no indication of a non-qbar q component in either f-meson state.

  16. Molecular models of the structural arrangement of subunits and the mechanism of proton translocation in the membrane domain of F(1)F(0) ATP synthase.

    PubMed

    Groth, G

    2000-05-31

    Subunit c of the proton-transporting ATP synthase of Escherichia coli forms an oligomeric complex in the membrane domain that functions in transmembrane proton conduction. The arrangement of subunit c monomers in this oligomeric complex was studied by scanning mutagenesis. On the basis of these studies and structural information on subunit c, different molecular models for the potential arrangement of monomers in the c-oligomer are discussed. Intersubunit contacts in the F(0) domain that have been analysed in the past by chemical modification and mutagenesis studies are summarised. Transient contacts of the c-oligomer with subunit a might play a crucial role in the mechanism of proton translocation. Schematic models presented by several authors that interpret proton transport in the F(0) domain by a relative rotation of the c-subunit oligomer against subunit a are reviewed against the background of the molecular models of the oligomer.

  17. Identification and validation of the mitochondrial F1F0-ATPase as the molecular target of the immunomodulatory benzodiazepine Bz-423.

    PubMed

    Johnson, Kathryn M; Chen, Xueni; Boitano, Anthony; Swenson, Lara; Opipari, Anthony W; Glick, Gary D

    2005-04-01

    Bz-423 is a 1,4-benzodiazepine that suppresses disease in lupus-prone mice by selectively killing pathogenic lymphocytes, and it is less toxic compared to current lupus drugs. Cells exposed to Bz-423 rapidly generate O(2)(-) within mitochondria, and this reactive oxygen species is the signal initiating apoptosis. Phage display screening revealed that Bz-423 binds to the oligomycin sensitivity conferring protein (OSCP) component of the mitochondrial F(1)F(0)-ATPase. Bz-423 inhibited the F(1)F(0)-ATPase in vitro, and reconstitution experiments demonstrated that inhibition was mediated by the OSCP. This target was further validated by generating cells with reduced OSCP expression using RNA interference and studying the sensitivity of these cells to Bz-423. Our findings help explain the efficacy and selectivity of Bz-423 for autoimmune lymphocytes and highlight the OSCP as a target to guide the development of novel lupus therapeutics.

  18. X-ray absorption and photoelectron spectroscopy investigation of selenite reduction by FeII-bearing minerals.

    PubMed

    Scheinost, Andreas C; Kirsch, Regina; Banerjee, Dipanjan; Fernandez-Martinez, Alejandro; Zaenker, Harald; Funke, Harald; Charlet, Laurent

    2008-12-12

    The long-lived radionuclide 79Se is one of the elements of concern for the safe storage of high-level nuclear waste, since clay minerals in engineered barriers and natural aquifer sediments strongly adsorb cationic species, but to lesser extent anions like selenate (SeVIO4(2-)) and selenite (SeIVO3(2-)). Previous investigations have demonstrated, however, that SeIV and SeVI are reduced by surface-associated FeII, thereby forming insoluble Se0 and Fe selenides. Here we show that the mixed FeII/III (hydr)oxides green rust and magnetite, and the FeII sulfide mackinawite reduce selenite rapidly (< 1 day) to FeSe, while the slightly slower reduction by the FeII carbonate siderite produces elemental Se. In the case of mackinawite, both S(-II) and FeII surface atoms are oxidized at a ratio of one to four by producing a defective mackinawite surface. Comparison of these spectroscopic results with thermodynamic equilibrium modeling provides evidence that the nature of reduction end product in these FeII systems is controlled by the concentration of HSe(-); Se0 forms only at lower HSe(-) concentrations related to slower HSeO3(-) reduction kinetics. Even under thermodynamically unstable conditions, the initially formed Se solid phases may remain stable for longer periods since their low solubility prevents the dissolution required for a phase transformation into more stable solids. The reduction by Fe2+-montmorillonite is generally much slower and restricted to a pH range, where selenite is adsorbed (pH < 7), stressing the importance of a heterogeneous, surface-enhanced electron transfer reaction. Although the solids precipitated by the redox reaction are nanocrystalline, their solubility remains below 6.3 x 10(-8) M. No evidence for aqueous metal selenide colloids nor for Se sorption to colloidal phases was found. Since FeII phases like the ones investigated here should be ubiquitous in the near field of nuclear waste disposals as well as in the surrounding aquifers

  19. Forward operation of adenine nucleotide translocase during F0F1-ATPase reversal: critical role of matrix substrate-level phosphorylation

    PubMed Central

    Chinopoulos, Christos; Gerencser, Akos A.; Mandi, Miklos; Mathe, Katalin; Töröcsik, Beata; Doczi, Judit; Turiak, Lilla; Kiss, Gergely; Konràd, Csaba; Vajda, Szilvia; Vereczki, Viktoria; Oh, Richard J.; Adam-Vizi, Vera

    2010-01-01

    In pathological conditions, F0F1-ATPase hydrolyzes ATP in an attempt to maintain mitochondrial membrane potential. Using thermodynamic assumptions and computer modeling, we established that mitochondrial membrane potential can be more negative than the reversal potential of the adenine nucleotide translocase (ANT) but more positive than that of the F0F1-ATPase. Experiments on isolated mitochondria demonstrated that, when the electron transport chain is compromised, the F0F1-ATPase reverses, and the membrane potential is maintained as long as matrix substrate-level phosphorylation is functional, without a concomitant reversal of the ANT. Consistently, no cytosolic ATP consumption was observed using plasmalemmal KATP channels as cytosolic ATP biosensors in cultured neurons, in which their in situ mitochondria were compromised by respiratory chain inhibitors. This finding was further corroborated by quantitative measurements of mitochondrial membrane potential, oxygen consumption, and extracellular acidification rates, indicating nonreversal of ANT of compromised in situ neuronal and astrocytic mitochondria; and by bioluminescence ATP measurements in COS-7 cells transfected with cytosolic- or nuclear-targeted luciferases and treated with mitochondrial respiratory chain inhibitors in the presence of glycolytic plus mitochondrial vs. only mitochondrial substrates. Our findings imply the possibility of a rescue mechanism that is protecting against cytosolic/nuclear ATP depletion under pathological conditions involving impaired respiration. This mechanism comes into play when mitochondria respire on substrates that support matrix substrate-level phosphorylation.—Chinopoulos, C., Gerencser, A. A., Mandi, M., Mathe, K., Töröcsik, B., Doczi, J., Turiak, L., Kiss, G., Konràd, C., Vajda, S., Vereczki, V., Oh, R. J., Adam-Vizi, V. Forward operation of adenine nucleotide translocase during F0F1-ATPase reversal: critical role of matrix substrate-level phosphorylation. PMID

  20. A spectroscopic investigation of captopril and the Cu(II) captopril system

    NASA Astrophysics Data System (ADS)

    Torreggiani, Armida; Taddei, Paola; Tosi, M. Raffaella; Tugnoli, Vitaliano

    2001-05-01

    A Raman and IR study of captopril (CpSH), a synthetic derivative of L-proline, and the Cu(II)-CpSH system at different pHs and metal/ligand ratios was carried out. The vibrational spectra suggested disulphide formation (CpSSCp) by the reduction of Cu(II) to Cu(I) and allowed the identification of the sites involved in metal coordination. Various complexes can be formed and the nature of the predominant species depends mainly on the pH. At pH 10 CpSH gives rise to two monomeric complexes with different structures depending on the metal/ligand ratio, whereas at acid pH a water-insoluble polymeric species predominates.

  1. Atomic Force Microscopy for Investigation of Ribosome-inactivating Proteins' Type II Tetramerization

    NASA Astrophysics Data System (ADS)

    Savvateev, M.; Kozlovskaya, N.; Moisenovich, M.; Tonevitsky, A.; Agapov, I.; Maluchenko, N.; Bykov, V.; Kirpichnikov, M.

    2003-12-01

    Biology of the toxins violently depends on their carbohydrate-binding centres' organization. Toxin tetramerization can lead to both increasing of lectin-binding centres' number and changes in their structural organization. A number and three-dimensional localization of such centres per one molecule strongly influence on toxins' biological properties. Ricin was used to obtain the AFM images of natural dimeric RIPsII structures as far as ricinus agglutinin was used for achievement of AFM images of natural tetrameric RIPsII forms. It is well-known that viscumin (60 kDa) has a property to form tetrameric structures dependently on ambient conditions and its concentration. Usage of the model dimer-tetramer based on ricin-agglutinin allowed to identify viscumin tetramers in AFM scans and to differ them from dimeric viscumin structures. Quantification analysis produced with the NT-MDT software allowed to estimate the geometrical parameters of ricin, ricinus agglutinin and viscumin molecules.

  2. F1F0-ATPase, early target of the radical initiator 2,2'-azobis-(2-amidinopropane) dihydrochloride in rat liver mitochondria in vitro.

    PubMed Central

    Beauseigneur, F; Goubern, M; Chapey, M F; Gresti, J; Vergely, C; Tsoko, M; Demarquoy, J; Rochette, L; Clouet, P

    1996-01-01

    This study was designed to determine which enzyme activities were first impaired in mitochondria exposed to 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), a known radical initiator. EPR spin-trapping revealed generation of reactive oxygen species although malondialdehyde formation remained very low. With increasing AAPH concentrations, State-3 respiration was progressively depressed with unaltered ADP/O ratios. A top-down approach demonstrated that alterations were located at the phosphorylation level. As shown by inhibitor titrations, ATP/ADP translocase activity was unaffected in the range of AAPH concentrations used. In contrast, AAPH appeared to exert a deleterious effect at the level of F1F0-ATPase, comparable with dicyclohexylcarbodi-imide, which alters Fo proton channel. A comparison of ATP hydrolase activity in uncoupled and broken mitochondria reinforced this finding. In spite of its pro-oxidant properties, AAPH was shown to act as a dose-dependent inhibitor of cyclosporin-sensitive permeability transition initiated by Ca2+, probably as a consequence of its effect on F1F0-ATPase. Resveratrol, a potent antiperoxidant, completely failed to prevent the decrease in State-3 respiration caused by AAPH. The data suggest that AAPH, when used under mild conditions, acted as a radical initiator and was capable of damaging F1F0-ATPase, thereby slowing respiratory chain activity and reducing mitochondrial antioxidant defences. PMID:8973568

  3. F1F0-ATPase, early target of the radical initiator 2,2'-azobis-(2-amidinopropane) dihydrochloride in rat liver mitochondria in vitro.

    PubMed

    Beauseigneur, F; Goubern, M; Chapey, M F; Gresti, J; Vergely, C; Tsoko, M; Demarquoy, J; Rochette, L; Clouet, P

    1996-12-01

    This study was designed to determine which enzyme activities were first impaired in mitochondria exposed to 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), a known radical initiator. EPR spin-trapping revealed generation of reactive oxygen species although malondialdehyde formation remained very low. With increasing AAPH concentrations, State-3 respiration was progressively depressed with unaltered ADP/O ratios. A top-down approach demonstrated that alterations were located at the phosphorylation level. As shown by inhibitor titrations, ATP/ADP translocase activity was unaffected in the range of AAPH concentrations used. In contrast, AAPH appeared to exert a deleterious effect at the level of F1F0-ATPase, comparable with dicyclohexylcarbodi-imide, which alters Fo proton channel. A comparison of ATP hydrolase activity in uncoupled and broken mitochondria reinforced this finding. In spite of its pro-oxidant properties, AAPH was shown to act as a dose-dependent inhibitor of cyclosporin-sensitive permeability transition initiated by Ca2+, probably as a consequence of its effect on F1F0-ATPase. Resveratrol, a potent antiperoxidant, completely failed to prevent the decrease in State-3 respiration caused by AAPH. The data suggest that AAPH, when used under mild conditions, acted as a radical initiator and was capable of damaging F1F0-ATPase, thereby slowing respiratory chain activity and reducing mitochondrial antioxidant defences.

  4. Phylogenetic analyses of the homologous transmembrane channel-forming proteins of the F0F1-ATPases of bacteria, chloroplasts and mitochondria.

    PubMed

    Blair, A; Ngo, L; Park, J; Paulsen, I T; Saier, M H

    1996-01-01

    Sequences of the three integral membrane subunits (subunits a, b and c) of the F0 sector of the proton-translocating F-type (F0F1-) ATPases of bacteria, chloroplasts and mitochondria have been analysed. All homologous-sequenced proteins of these subunits, comprising three distinct families, have been identified by database searches, and the homologous protein sequences have been aligned and analysed for phylogenetic relatedness. The results serve to define the relationships of the members of each of these three families of proteins, to identify regions of relative conservation, and to define relative rates of evolutionary divergence. Of these three subunits, c-subunits exhibited the slowest rate of evolutionary divergence, b-subunits exhibited the most rapid rate of evolutionary divergence, and a-subunits exhibited an intermediate rate of evolutionary divergence. The results allow definition of the relative times of occurrence of specific events during evolutionary history, such as the intragenic duplication event that gave rise to large c-subunits in eukaryotic vacuolar-type ATPases after eukaryotes diverged from archaea, and the extragenic duplication of F-type ATPase b-subunits that occurred in blue-green bacteria before the advent of chloroplasts. The results generally show that the three F0 subunits evolved as a unit from a primordial set of genes without appreciable horizontal transmission of the encoding genetic information although a few possible exceptions were noted.

  5. Nonlinear optical investigation of the Tris(2‧,2-bipyridyl)iron(II) tetrafluoroborate using z-scan technique

    NASA Astrophysics Data System (ADS)

    Zidan, M. D.; Al-Ktaifani, M. M.; Allahham, A.

    2017-05-01

    Z-scan measurements were performed with a CW diode laser at 635 nm to investigate the nonlinear optical properties of Tris(2‧,2-bipyridyl)iron(II) tetrafluoroborate in ethanol at two concentrations. Theoretical fit was carried out to evaluate the nonlinear absorption coefficient (β) and the negative nonlinear refractive index (n2) for the studied complex. Furthermore, the ground-state absorption cross sections (σg), the excited-state absorption cross sections (σex) and thermo-optic coefficient were also estimated. The investigations show large NLO response, which is predominantly associated with substantial conjugation between the aromatic ring π-electron system and d-electron set metal center. The obtained results give a strong indication that Tris(2‧,2-bipyridyl)iron(II) tetrafluoroborate have a potential application in optical domain.

  6. Cultural Resources Investigations at Redstone Arsenal, Madison County, Alabama. Volume II.

    DTIC Science & Technology

    1980-01-01

    was an infant or child . Parts of broken pottery vessels were found with two of the burials. I As mentioned above, ceramics were relatively infrequent...ai-j- IL is also due to a certain amiount of I tI ’rt ie 1(a ao -- tilit- iV! t-ri i process does not porn i t an extant I ii tfel to !, -,I) Ip it

  7. Evolutionary behaviour of AGN: Investigations on BL Lac objects and Seyfert II galaxies

    NASA Astrophysics Data System (ADS)

    Beckmann, V.

    2000-12-01

    The evolution and nature of AGN is still one of the enigmatic questions in astrophysics. While large and complete Quasar samples are available, special classes of AGN, like BL Lac objects and Seyfert II galaxies, are still rare objects. In this work I present two new AGN samples. The first one is the HRX-BL Lac survey, resulting in a sample of X-ray selected BL Lac objects. This sample results from 223 BL Lac candidates based on a correlation of X-ray sources with radio sources. The identification of this sample is 98% complete. 77 objects have been identified as BL Lac objects and form the HRX-BL Lac complete sample, the largest homogeneous sample of BL Lac objects existing today. For this sample, redshifts are now known for 62 objects (81 %). In total I present 101 BL Lac objects in the enlarged HRX-BL Lac survey, for which redshift information is available for 84 objects. During the HRX-BL Lac survey I found several objects of special interest. 1ES 1517+656 turned out to be the brightest known BL Lac object in the universe. 1ES 0927+500 could be the first BL Lac object with a line detected in the X-ray region. RX J1211+2242 is probably the the counterpart of the up to now unidentified gamma-ray source 3EG J1212+2304. Additionally I present seven candidates for ultra high frequency peaked BL Lac objects. RX J1054+3855 and RX J1153+3517 are rare high redshift X-ray bright QSO or accreting binary systems with huge magnetic fields. For the BL Lac objects I suggest an unified scenario in which giant elliptical galaxies, formed by merging events of spiral galaxies at z > 2, start as powerful, radio dominated BL Lacs. As the jet gets less powerful, the BL Lacs start to get more X-ray dominated, showing less total luminosities (for z < 1). This effect is seen in the different evolutionary behavior detected in high and low frequency cut off BL Lac objects (HBL and LBL, respectively). The model of negative evolution is supported by assumptions about the energetic effects

  8. An Investigation Of The Metallicity Dependence Of The Sn Type Ii Mn Production

    NASA Astrophysics Data System (ADS)

    Kim, Yeunjin; Sobeck, J.; Frohlich, C.; Truran, J.

    2010-01-01

    Element abundance trends over the history of our Galaxy serve as important guides in establishing relative contributions from supernovae of Types Ia and II. In particular, spectroscopic studies have revealed a deficiency of manganese (Mn) relative to the abundances of neighboring iron-peak nuclei in metal-poor stars. However, more recent analyses of the observational data have found a constant Mn/Fe abundance ratio over a wide range of metallicity and hence, contradict these previous findings. In this project, we will study the nucleosynthetic yields of Type II supernovae as a function of metallicity by parameterizing the initial properties of the shock. We will compare our results with the two distinct manganese abundance trends identified above. Once we study the metallicity dependency of Type II yields as reflected in observations at lower metallicities, we will explore the constraints this imposes on Type Ia supernova contributions to Mn in different stellar and galactic populations. We acknowledge the financial support by the National Science Foundation for the Frontier Center Joint Institute for Nuclear Astrophysics (JINA). C.F. acknowledges an Enrico Fermi Fellowship.

  9. A qualitative investigation of hypomania and depression in bipolar II disorder.

    PubMed

    Fletcher, Kathryn; Parker, Gordon; Manicavasagar, Vijaya

    2013-12-01

    Psychological treatments may have differential impacts on bipolar (BP) sub-types, yet little is known about psychological processes in BP II disorder. We explored cognitive processes and behaviors mediating hypomania and depression in participants diagnosed with BP II disorder. Semi-structured interviews with 13 participants were analysed using interpretative phenomenological analysis. The majority were able to detect hypomanic and depressive prodromes, and describe behavioral responses to these mood states. Qualitative analyses revealed four theme clusters. Hypomania ascent beliefs described beliefs regarding identity, positioning hypomania as an enjoyable state preferable to depression. Hypomania descent beliefs referred to hypomania as a signal for depression, causing interpersonal difficulties. Beliefs about depression positioned depression as an abnormal, fearful state, impacting negatively interpersonally, occupationally and on self-perceptions. Finally, The impact of chronicity referred to shifts in coping strategies over time, moving from maladaptive to adaptive behavioral responses. Themes were interpreted within the framework of a cognitive model of BP disorder. Clinical implications for BP II disorder were discussed.

  10. Investigation of the strontium (Sr(II)) adsorption of an alginate microsphere as a low-cost adsorbent for removal and recovery from seawater.

    PubMed

    Hong, Hye-Jin; Ryu, Jungho; Park, In-Su; Ryu, Taegong; Chung, Kang-Sup; Kim, Byuong-Gyu

    2016-01-01

    In this paper, we investigated alginate microspheres as a low-cost adsorbent for strontium (Sr(II)) removal and recovery from seawater. Alginate microspheres have demonstrated a superior adsorption capacity for Sr(II) ions (≈110 mg/g). A Freundlich isotherm model fits well with the Sr(II) adsorption of an alginate microsphere. The mechanism of Sr(II) adsorption is inferred as an ion exchange reaction with Ca(II) ions. The effects of the solution pH and co-existing ions in seawater are also investigated. Except for a pH of 1-2, Sr(II) adsorption capacity is not affected by pH. However, increasing the seawater concentration of metal cations seriously decreases Sr(II) uptake. In particular, highly concentrated (15,000 mg/L) Na(I) ions significantly interfere with Sr(II) adsorption. Sr(II) desorption was performed using 0.1 M HCl and CaCl2. Both regenerants show an excellent desorption efficiency, but the FTIR spectrum reveals that the chemical structure of the microsphere is destroyed after repeated use of HCl. Conversely, CaCl2 successfully desorbed Sr(II) without damage, and the Sr(II) adsorption capacity does not decrease after three repeated uses. The alginate microsphere was also applied to the adsorption of Sr(II) in a real seawater medium. Because of inhibition by co-existing ions, the Sr(II) adsorption capacity was decreased and the adsorption rate was retarded compared with D.I. water. Although the Sr(II) adsorption capacity was decreased, the alginate microsphere still exhibited 17.8 mg/g of Sr(II) uptake in the seawater medium. Considering its excellent Sr(II) uptake in seawater and its reusability, an alginate microsphere is an appropriate cost-effective adsorbent for the removal and recovery of Sr(II) from seawater.

  11. Magnetotransport and thermal properties characterization of 55 K superconductor SmFeAsO0.85F0.15

    NASA Astrophysics Data System (ADS)

    Srivastava, Amit; Pal, Anand; Singh, Saurabh; Shekhar, C.; Singh, H. K.; Awana, V. P. S.; Srivastava, O. N.

    2013-09-01

    This report fairly underlines the magneto-transport, thermal properties characterization and bulk superconductivity in the FeAs-based SmFeAsO0.85F0.1. The phase formation and structure are confirmed by Rietveld analysis of room temperature powder X-ray diffraction (XRD) data. Electron microscopy was employed to unravel the micro structural details, such as perfection of the lattice and the grain morphology including size and boundaries. The electrical and magnetic measurements have been carried out to confirm the bulk superconductivity and understand the nature of electrical transport in the normal and superconducting state. The intra-grain critical current density (Jc) with applied magnetic field is calculated from isothermal DC magnetization (MH) plots using conventional Bean critical state model. Superconductivity is observed at transition temperature (Tc) above 55 K without HPHT (high pressure high temperature) synthesis route. The value of Jc is found to be around 5.26 × 104 A/cm2 at 5 K in zero field. The dependence of thermally activated flux flow energy (U/kB) on the applied magnetic field has been observed. AC susceptibility measurements were performed for 55 K superconducting SmFeAsO0.85F0.15 sample at various amplitude of applied AC drive field and its granular nature is confirmed. The parent compound SmFeAsO is found to be magnetic with Fe spin density wave (SDW) like order below 150 K, on the other hand the F doped SmFeAsO0.85F0.15 sample is bulk superconducting at below 55 K. Both Fe (SDW) at 150 K for SmFeAsO and 55 K superconductivity in case of SmFeAsO0.85F0.15 sample has confirmed by Specific heat [Cp(T)] measurement too. Further Sm orders anti-ferro-magnetically at 4.5 K for non-superconducting and at 3.5 K for superconducting samples, also the entropy change is reduced significantly for the later than the former. Summarily complete physical property characterization for both non-superconducting SmFeAsO and 55 K superconductor SmFeAsO0.85F0

  12. Cross-reconstitution of the F0F1-ATP synthases of chloroplasts and Escherichia coli with special emphasis on subunit delta.

    PubMed

    Engelbrecht, S; Deckers-Hebestreit, G; Altendorf, K; Junge, W

    1989-05-01

    F0F1-ATP synthases catalyse ATP formation from ADP and Pi by using the free energy supplied by the transmembrane electrochemical potential of the proton. The delta subunit of F1 plays an important role at the interface between the channel portion F0 and the catalytic portion F1. In chloroplasts it can plug the protonic conductance of CF0 and in Escherichia coli it is required for binding of EF1 to EF0. We wanted to know whether or not delta of one species was effective between F0 and F1 of the other species and vice versa. To this end the respective coupling membrane (thylakoids, everted vesicles from E. coli) was (partially) depleted of F1 and purified F1, F1(-delta), and delta were added in various combinations to the F1-depleted membranes. The efficiency or reconstitution was measured in thylakoids via the rate of phenazinemethosulfate-mediated cyclic photophosphorylation and in E. coli everted vesicles via the degree of 9-amino-6-chloro-2-methoxyacridine fluorescence quenching. Addition of CF1 to partially CF1-depleted thylakoid vesicles restored photophosphorylation to the highest extent. CF1(-delta)+chloroplast delta, EF1, EF1(-delta)+E. coli delta were also effective but to lesser extent. CF1(-delta)+E. coli delta and EF1(-delta)+chloroplast delta restored photophosphorylation to a small but still significant extent. With F1-depleted everted vesicles prepared by repeated EDTA treatment of E. coli membranes, addition of CF1, CF1 (-delta)+chloroplast delta and CF1(-delta)+E. coli delta gave approximately half the extent of 9-amino-6-chloro-2-methoxyacridine fluorescence quenching as compared to EF1 or EF1(-delta)+E. coli delta by energization of the vesicles with NADH, while Ef1(-delta)+chloroplast delta was ineffective. All 'mixed' combinations were probably reconstitutively active only by plugging the protonic leak through the exposed F0 (structural reconstitution) rather than by catalytic activity. Nevertheless, the cross-reconstitution is stunning in view

  13. Transcriptional analysis of the F0F1 ATPase operon of Corynebacterium glutamicum ATCC 13032 reveals strong induction by alkaline pH.

    PubMed

    Barriuso-Iglesias, Mónica; Barreiro, Carlos; Flechoso, Fabio; Martín, Juan F

    2006-01-01

    Corynebacterium glutamicum, a soil Gram-positive bacterium used for industrial amino acid production, was found to grow optimally at pH 7.0-9.0 when incubated in 5 litre fermenters under pH-controlled conditions. The highest biomass was accumulated at pH 9.0. Growth still occurred at pH 9.5 but at a reduced rate. The expression of the pH-regulated F0 F1 ATPase operon (containing the eight genes atpBEFHAGDC) was induced at alkaline pH. A 7.5 kb transcript, corresponding to the eight-gene operon, was optimally expressed at pH 9.0. The same occurred with a 1.2 kb transcript corresponding to the atpB gene. RT-PCR studies confirmed the alkaline pH induction of the F0 F1 operon and the existence of the atpI gene. The atpI gene, located upstream of the F0 F1 operon, was expressed at a lower level than the polycistronic 7.5 kb mRNA, from a separate promoter (P-atp1). Expression of the major promoter of the F0 F1 operon, designated P-atp2, and the P-atp1 promoter was quantified by coupling them to the pET2 promoter-probe vector. Both P-atp1 and P-atp2 were functional in C. glutamicum and Escherichia coli. Primer extension analysis identified one transcription start point inside each of the two promoter regions. The P-atp1 promoter fitted the consensus sequence of promoters recognized by the vegetative sigma factor of C. glutamicum, whereas the -35 and -10 boxes of P-atp2 fitted the consensus sequence for sigma(H)-recognized Mycobacterium tuberculosis promoters C(C)/(G)GG(A)/(G)AC 17-22 nt (C)/(G)GTT(C)/(G), known to be involved in expression of heat-shock and other stress-response genes. These results suggest that the F0 F1 operon is highly expressed at alkaline pH, probably using a sigma (H) RNA polymerase.

  14. Theoretical and Experimental Investigations of (I) Reaction Kinetics. (II) Theory of Liquids, and (III) Optical Rotation

    DTIC Science & Technology

    1975-02-14

    The "region of indifference" to a phase change with pressure in camphor has been found to decrease markedly with purification. Mini (continued on...for High Pressure Transitions in d- Camphor (TI-III) and Phosphorus (I-II)", by A. F. Gabrysh, A. Vanhook and H. Eyring, J. Phys. Chem. Solids, 25, 129...on the transformation in d- camphor and phosphorus. The so-called "region of ind;ffer’e,-e" rennrted as approximately .38 kilobars in phosphorus, was

  15. Investigations of the Binding of [Pt2(DTBPA)Cl2](II) and [Pt2(TPXA)Cl2](II) to DNA via Various Cross-Linking Modes

    PubMed Central

    Yue, Hongwei; Yang, Bo; Wang, Yan; Chen, Guangju

    2013-01-01

    We have constructed models for a series of platinum-DNA adducts that represent the binding of two agents, [Pt2(DTBPA)Cl2](II) and [Pt2(TPXA)Cl2](II), to DNA via inter- and intra-strand cross-linking, and carried out molecular dynamics simulations and DNA conformational dynamics calculations. The effects of trans- and cis-configurations of the centers of these di-nuclear platinum agents, and of different bridging linkers, have been investigated on the conformational distortions of platinum-DNA adducts formed via inter- and intra-strand cross-links. The results demonstrate that the DNA conformational distortions for the various platinum-DNA adducts with differing cross-linking modes are greatly influenced by the difference between the platinum-platinum distance for the platinum agent and the platinum-bound N7–N7 distance for the DNA molecule, and by the flexibility of the bridging linkers in the platinum agent. However, the effects of trans/cis-configurations of the platinum-centers on the DNA conformational distortions in the platinum-DNA adducts depend on the inter- and intra-strand cross-linking modes. In addition, we discuss the relevance of DNA base motions, including opening, shift and roll, to the changes in the parameters of the DNA major and minor grooves caused by binding of the platinum agent. PMID:24077126

  16. Upper Critical Field, Critical Current Density and Activation Energy of the New La1-xSmxO0.5F0.5BiS2 (x = 0.2, 0.8) Superconductors

    NASA Astrophysics Data System (ADS)

    Kalai Selvan, Ganesan; Singh Thakur, Gohil; Manikandan, Krishnan; Uwatoko, Yoshia; Haque, Zeba; Gupta, Laxmi Chand; Ganguli, Ashok Kumar; Arumugam, Sonachalam

    2015-12-01

    Critical current density (Jc), thermal activation energy (U0), and upper critical field (Hc2) of La1-xSmxO0.5F0.5BiS2 (x = 0.2, 0.8) superconductors are investigated from magnetic field dependent ρ(T) studies. The estimated upper critical field (Hc2) has low values of 1.04 T for x = 0.2 and 1.41 T for x = 0.8. These values are lower than Sm free LaO0.5F0.5BiS2 superconductor (1.9 T). The critical current density (Jc) is estimated to be 1.35 × 105 and 5.07 × 105 A/cm2 (2 K) for x = 0.2 and 0.8 respectively, using the Bean's model. The thermal activation energy (U0/kB) is 61 K for x = 0.2 and 140 K for x = 0.8 as calculated from Arrhenius plots at low magnetic field (1 T) and indicates a strong flux pinning potential which might be co-existing with applied magnetic field.

  17. Superconductivity in La1-x Sm x O0.5F0.5BiS2 (x  =  0.2, 0.8) under hydrostatic pressure

    NASA Astrophysics Data System (ADS)

    Kalai Selvan, G.; Thakur, Gohil S.; Manikandan, K.; Banerjee, A.; Haque, Zeba; Gupta, L. C.; Ganguli, Ashok K.; Arumugam, S.

    2016-07-01

    We have investigated the pressure effect on the newly discovered samarium-doped La1-x Sm x O0.5F0.5BiS2 superconductors. More than a threefold increase in T c (10.3 K) is observed with external pressure (at ~1.74 GPa at a rate of 4.08 K GPa-1) for x  =  0.2 composition. There is a concomitant large improvement in the quality of the superconducting transition. Beyond this pressure T c decreases monotonously at the rate of  -2.09 K GPa-1. In the x  =  0.8 sample, we do not observe any enhancement in T c with the application of pressure (up to 1.76 GPa). The semiconducting behavior observed in the normal-state resistivity of both samples is significantly subdued with the application of pressure which, if interpreted by invoking the thermal activation process, implies that the activation energy gap of the carriers is significantly reduced with pressure. We believe these observations should generate further interest in La1-x Sm x O0.5F0.5BiS2 superconductors.

  18. Structure and spectroscopic investigations of a bi-dentate N‧-[(4-ethylphenyl)methylidene]-4-hydroxybenzohydrazide and its Co(II), Ni(II), Cu(II) and Cd(II) complexes: Insights relevant to biological properties

    NASA Astrophysics Data System (ADS)

    Gopal Reddy, N. B.; Krishna, P. Murali; Shantha Kumar, S. S.; Patil, Yogesh P.; Nethaji, Munirathinam

    2017-06-01

    The present paper describes the synthesis of novel ligand, N‧-[(4-ethylphenyl)methylidene]-4-hydroxy benzohydrazide (HL) and its Co(II), Ni(II), Cu(II) and Cd(II) complexes. The ligand (HL) crystallizes in orthorhombic lattice in P212121 space group with a = 7.9941 (7) Å, b = 11.6154 (10) Å, c = 15.2278 (13) Å, α = β = γ = 90°. Spectroscopic data gives the strong evidence that ligand is coordinated through azomethine nitrogen and enolic oxygen with metal ion. The DNA binding studies revealed that the complexes bind to CT-DNA via intercalation/electrostatic interaction. All the targeted compounds showed more pronounced DNA cleavage activity in the presence of H2O2 and also inhibit the growth of in vitro antibacterial activity against Gram-positive and Gram-negative bacteria.

  19. SERS and DFT investigation of 1-(2-pyridylazo)-2-naphthol and its metal complexes with Al(III), Mn(II), Fe(III), Cu(II), Zn(II) and Pb(II)

    NASA Astrophysics Data System (ADS)

    Szabó, László; Herman, Krisztian; Mircescu, Nicoleta E.; Fălămaş, Alexandra; Leopold, Loredana F.; Leopold, Nicolae; Buzumurgă, Claudia; Chiş, Vasile

    The development of surface-enhanced Raman scattering (SERS) as a prospective analytical methodology for detection of metal ions was shown in recent years by several studies on metal complexes. In this work, 1-(2-pyridylazo)-2-naphthol (PAN) and its Al(III), Mn(II), Fe(III), Cu(II), Zn(II) and Pb(II) complexes were studied by FTIR, FT-Raman and surface enhanced Raman spectroscopies. Molecular geometry optimization, molecular electrostatic potential (MEP) distribution and vibrational frequencies calculations were performed using the hybrid B3LYP exchange-correlation functional for the PAN molecule and its bidentate complexes. The calculated MEP distributions indicated the atoms with highest electronegativity, the adsorption to the silver surface occurring through these atoms. Based on experimental and theoretical data we were able to identify unique and representative features, useful for the identification of each PAN-metal complex.

  20. SERS and DFT investigation of 1-(2-pyridylazo)-2-naphthol and its metal complexes with Al(III), Mn(II), Fe(III), Cu(II), Zn(II) and Pb(II).

    PubMed

    Szabó, László; Herman, Krisztian; Mircescu, Nicoleta E; Fălămaş, Alexandra; Leopold, Loredana F; Leopold, Nicolae; Buzumurgă, Claudia; Chiş, Vasile

    2012-07-01

    The development of surface-enhanced Raman scattering (SERS) as a prospective analytical methodology for detection of metal ions was shown in recent years by several studies on metal complexes. In this work, 1-(2-pyridylazo)-2-naphthol (PAN) and its Al(III), Mn(II), Fe(III), Cu(II), Zn(II) and Pb(II) complexes were studied by FTIR, FT-Raman and surface enhanced Raman spectroscopies. Molecular geometry optimization, molecular electrostatic potential (MEP) distribution and vibrational frequencies calculations were performed using the hybrid B3LYP exchange-correlation functional for the PAN molecule and its bidentate complexes. The calculated MEP distributions indicated the atoms with highest electronegativity, the adsorption to the silver surface occurring through these atoms. Based on experimental and theoretical data we were able to identify unique and representative features, useful for the identification of each PAN-metal complex.

  1. Thiocyanate-free cyclometalated ruthenium(II) sensitizers for DSSC: a combined experimental and theoretical investigation.

    PubMed

    Chitumalla, Ramesh Kumar; Gupta, Kankatala S V; Malapaka, Chandrasekhram; Fallahpour, Reza; Islam, Ashraful; Han, Liyuan; Kotamarthi, Bhanuprakash; Singh, Surya Prakash

    2014-02-14

    In an effort to bring out efficient thiocyanate-free dyes for dye sensitized solar cells (DSSC) we have designed, synthesized and characterized four novel cyclometalated ruthenium(II) dyes (M1 to M4) with superior photochemical properties. All dyes contain terpyridyl ligands (TPY) with carboxylic acids as anchoring groups and cyclometalated ligand (TPY-C) with substituents for fine tuning the electronic properties. We obtain a broad absorption band which extends up to 725 nm due to metal to ligand charge transfer (MLCT) when donating groups are used, which slightly blue-shifts when a withdrawing group is used. In addition to the CT, small HOMO-LUMO gaps are obtained from electrochemical measurements which indicate characteristics of an ideal sensitizer. All four dyes were used as sensitizers for DSSC and photoelectrochemical measurements were carried out. Reasonably good efficiency (7.1%) has been achieved for . We have carried out periodic-DFT studies of these dyes adsorbed on the (TiO2)38 cluster. They revealed that, in bidentate bridging mode the dyes preferably bind with the help of two carboxylic groups onto the TiO2. To the best of our knowledge we are the first to do DFT studies of thiocyanate free cyclometalated ruthenium(ii) dyes tethered to TiO2.

  2. Investigational drugs in phase I and phase II clinical trials for thalassemia.

    PubMed

    Motta, Irene; Scaramellini, Natalia; Cappellini, Maria Domenica

    2017-07-01

    Regular transfusion and iron chelation are the current treatment of severe forms of thalassemia. As a consequence of this demanding supportive treatment, there are several unmet therapeutic needs. Due to a deeper understanding in the pathophysiology of thalassemia, new therapeutic strategies have been developed that are now in pre-clinical and clinical trials. Areas covered: Activin receptor ligand traps (luspatercept and sotatercept), drugs targeting ineffective erythropoiesis, showed encouraging results in Phase I and II clinical trials. A phase III clinical trial is currently ongoing. Ruxolitinib, a Jak2 inhibitor, has been tested to limit stress erythropoiesis in a phase II clinical trial. In addition, improvement in iron chelation has been developed. Moreover, several trials of gene therapy are currently active in different countries with different lentiviral vectors. Expert opinion: The most promising molecules are the activin receptor ligand traps. Together with gene therapy these could be an alternative to bone marrow transplant, aiming towards a curative strategy. The main limit to gene therapy seems to be the conditioning regimen, thus an in vivo gene therapy would be more suitable. At pre-clinical level gene editing is showing extremely encouraging results.

  3. An Electrochemical Investigation of Fe(II) Dissolved in a Cryolite Melt

    NASA Astrophysics Data System (ADS)

    Jentoftsen, Trond E.; Dewing, Ernest W.; Lorentsen, Odd-Arne; Haarberg, Geir M.; Thonstad, Jomar

    2012-08-01

    Chronopotentiometric studies were made on a cryolite melt containing 3.0 wt pct Al2O3 and 0.466 wt pct Fe(II) at 1293 K (1020 °C). The diffusion coefficient calculated from the time of the principal chronopotentiometric transition decreased as the current density was increased, and at the same time, a second subsequent transition appeared. The diffusion coefficient calculated from this second transition was constant at 5.44 × 10-5 cm2 s-1. The results were interpreted to show that Fe(II) in the solution exists in two forms. Fe is deposited reversibly from an active form; its exchange current density must be >1 A cm-2. Deposition from the other form is irreversible, and it occurs directly only at high overpotentials, leading to the second transition. The equilibrium constant [active]/[inactive] = 5.4. When the equilibrium is displaced by electrolysis of the active form, the inactive form decomposes to replenish it with a rate constant of 0.9 s-1. The Tafel curve for the direct deposition of the inactive form shows a slope of 113 mV/decade, which is interpreted as n = 2 and a symmetry factor ≈1. The exchange current density is approximately 0.3 μA cm-2. The active and inactive forms are identified tentatively as FeF{3/-} and FeF{5/3-}, respectively.

  4. Spectral characteristic investigation on complex of Ni (II) with captopril and its analytical application

    NASA Astrophysics Data System (ADS)

    Wei, Xiaoling; Du, Liangwei; Li, Dongmei; Gong, Qi; Wang, Lisheng; Lin, Yu

    In this paper, Ni (II) reacting with captopril (CPT) can form complex in alkaline solution and the formed complex has a characteristic absorption peak at 340 nm. The absorbance of the Ni-CPT complex increases linearly with the increased concentration of captopril. The study also shows that ammonia has an obvious sensitizing effect on the absorbance. Based on the study, a new method for the determination of captopril is established. Experimental results show that the linear range of this method under optimum condition is 1.0-60 mg/L with correlation coefficient, detection limit and precision of 0.9999, 0.31 mg/L and 0.87%, respectively. The method used to determine captopril in commercial captopril tablets has a satisfactory result with the recoveries in the range of 99.0-103.6% and the relative standard deviation (RSD) in the range of 0.8-3.7%. We preliminarily study the reaction mechanism and demonstrate that the complex ratio of Ni (II) with captopril is 1:2 and the formation constant is 6.3 × 109.

  5. Spectral characteristic investigation on complex of Ni (II) with captopril and its analytical application.

    PubMed

    Wei, Xiaoling; Du, Liangwei; Li, Dongmei; Gong, Qi; Wang, Lisheng; Lin, Yu

    2012-08-01

    In this paper, Ni (II) reacting with captopril (CPT) can form complex in alkaline solution and the formed complex has a characteristic absorption peak at 340nm. The absorbance of the Ni-CPT complex increases linearly with the increased concentration of captopril. The study also shows that ammonia has an obvious sensitizing effect on the absorbance. Based on the study, a new method for the determination of captopril is established. Experimental results show that the linear range of this method under optimum condition is 1.0-60mg/L with correlation coefficient, detection limit and precision of 0.9999, 0.31mg/L and 0.87%, respectively. The method used to determine captopril in commercial captopril tablets has a satisfactory result with the recoveries in the range of 99.0-103.6% and the relative standard deviation (RSD) in the range of 0.8-3.7%. We preliminarily study the reaction mechanism and demonstrate that the complex ratio of Ni (II) with captopril is 1:2 and the formation constant is 6.3×10(9). Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Sorption of Nickel(II) on a Calcareous Aridisol Soil, China: Batch, XPS, and EXAFS Spectroscopic Investigations

    PubMed Central

    Qiang, Shirong; Han, Bin; Zhao, Xiaolan; Yang, Yunbo; Shao, Dadong; Li, Ping; Liang, Jianjun; Fan, Qiaohui

    2017-01-01

    The sorption of Ni(II) on a calcareous aridisol (CA) soil, one of the major soil types in northwestern China, was investigated using batch and extended X-ray absorption fine structure (EXAFS) approaches in a 0.01 mol/L NaClO4 solution at different pH values (6.0–10.0), temperatures (25–60 °C) and contact times (2–15 days). Under alkaline conditions, EXAFS analysis showed that the interatomic distances between Ni and O atoms (RNi-O) were approximately 2.04 Å with a typical coordination number (CN) of ~6.0 O atoms in the contact time range from 2 to 15 days. The RNi-Ni (~3.07 Å) suggested that the structure of the Ni(II) adsorbed on the CA soil was basically the same as that of Ni(OH)2(s), while the Ni-Al shell (RNi-Al ~3.16 Å) gradually formed and grew with the increasing contact time. Under weakly acidic conditions, the sorption mechanism of Ni(II) on the CA soil possibly included at least two processes: (i) a fast accumulation dominated by ion exchange and surface complexation and (ii) the formation of a Ni-Al LDH phase over the long term. A high temperature is beneficial to the fixation of Ni(II) on the CA soil and the formation of a Ni-Al LDH. PMID:28440287

  7. Sorption of Nickel(II) on a Calcareous Aridisol Soil, China: Batch, XPS, and EXAFS Spectroscopic Investigations

    NASA Astrophysics Data System (ADS)

    Qiang, Shirong; Han, Bin; Zhao, Xiaolan; Yang, Yunbo; Shao, Dadong; Li, Ping; Liang, Jianjun; Fan, Qiaohui

    2017-04-01

    The sorption of Ni(II) on a calcareous aridisol (CA) soil, one of the major soil types in northwestern China, was investigated using batch and extended X-ray absorption fine structure (EXAFS) approaches in a 0.01 mol/L NaClO4 solution at different pH values (6.0-10.0), temperatures (25-60 °C) and contact times (2-15 days). Under alkaline conditions, EXAFS analysis showed that the interatomic distances between Ni and O atoms (RNi-O) were approximately 2.04 Å with a typical coordination number (CN) of ~6.0 O atoms in the contact time range from 2 to 15 days. The RNi-Ni (~3.07 Å) suggested that the structure of the Ni(II) adsorbed on the CA soil was basically the same as that of Ni(OH)2(s), while the Ni-Al shell (RNi-Al ~3.16 Å) gradually formed and grew with the increasing contact time. Under weakly acidic conditions, the sorption mechanism of Ni(II) on the CA soil possibly included at least two processes: (i) a fast accumulation dominated by ion exchange and surface complexation and (ii) the formation of a Ni-Al LDH phase over the long term. A high temperature is beneficial to the fixation of Ni(II) on the CA soil and the formation of a Ni-Al LDH.

  8. A comparative investigation of the thermal unfolding of pseudoazurin in the Cu(II)-holo and apo form.

    PubMed

    Stirpe, Andrea; Sportelli, Luigi; Guzzi, Rita

    2006-12-05

    The contribution of the copper ion to the stability and to the unfolding pathway of pseudoazurin was investigated by a comparative analysis of the thermal unfolding of the Cu(II)-holo and apo form of the protein. The unfolding has been followed by calorimetry, fluorescence, optical density, and electron paramagnetic resonance (EPR) spectroscopy. The thermal transition of Cu(II)-holo pseudoazurin is irreversible and occurs between 60.0 and 67.3 degrees C, depending on the scan rate and technique used. The denaturation pathway of Cu(II)-holo pseudoazurin can be described by the Lumry-Eyring model: N --> U --> [corrected] F; the protein reversibly goes from the native (N) to the unfolded (U) state, and then irreversibly to the final (F) state. The simulation of the experimental calorimetric profiles, according to this model, allowed us to determine the thermodynamic and kinetic parameters of the two steps. The DeltaG value calculated for the Cu(II)-holo pseudoazurin is 39.2 kJ.mol(-1) at 25 degrees C. The sequence of events in the denaturation process of Cu(II)-holo pseudoazurin emergence starts with the disruption of the copper site and the hydrophobic core destabilization followed by the global protein unfolding. According to the EPR findings, the native type-1 copper ion shows type-2 copper features after the denaturation. The removal of the copper ion (apo form) significantly reduces the stability of the protein as evidenced by a DeltaG value of 16.5 kJ.mol(-1) at 25 degrees C. Moreover, the apo Paz unfolding occurs at 41.8 degrees C and is compatible with a two-state reversible process N --> [corrected] U.

  9. Metabolism of methandrostenolone in the horse: a gas chromatographic-mass spectrometric investigation of phase I and phase II metabolism.

    PubMed

    McKinney, A R; Ridley, D D; Suann, C J

    2001-12-05

    The phase I and phase II metabolism of the anabolic steroid methandrostenolone was investigated following oral administration to a standardbred gelding. In the phase I study, metabolites were isolated from the urine by solid-phase extraction, deconjugated by acid catalysed methanolysis and converted to their O-methyloxime trimethylsilyl derivatives. GC-MS analysis indicated the major metabolic processes to be sequential reduction of the A-ring and hydroxylation at C6 and C16. In the phase II study, unconjugated, beta-glucuronidated and sulfated metabolites were fractionated and deconjugated using a combination of liquid-liquid extraction, enzyme hydrolysis, solid-phase extraction and acid catalysed methanolysis. Derivatization followed by GC-MS analysis revealed extensive conjugation to both glucuronic and sulfuric acids, with only a small proportion of metabolites occurring in unconjugated form.

  10. Diaquachloro-tris(ethyl-p-Aminobenzoate)copper(II) Chloride: Synthesis, Characterization and In Vitro Investigation of Antibacterial Activity

    NASA Astrophysics Data System (ADS)

    Rahardjo, S. B.; Lestari, W. W.; Syaima, H.

    2017-07-01

    The new complex of [Cu(benz)3(H2O)2Cl]Cl has been synthesized in 1:4 mole ratio of CuCl2·2H2O and ethyl-p-aminobenzoate (benz) in ethanol at room temperature. The complex was characterized by UV-Vis and infrared spectroscopy, Atomic Absorption Spectroscopy (AAS), thermal analysis, magnetic measurement and molar conductivity. Infrared spectra indicated that benz was coordinated to the metal ion through nitrogen of primary amine group. Water molecules and chloride ion were also coordinated to Cu(II). CuCl2·2H2O, benz, and Cu(II) complex were screened for investigating in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli using a modified Kirby-Bauer method.

  11. Experimental investigation on the mechanism of chelation-assisted, copper(II) acetate-accelerated azide-alkyne cycloaddition.

    PubMed

    Kuang, Gui-Chao; Guha, Pampa M; Brotherton, Wendy S; Simmons, J Tyler; Stankee, Lisa A; Nguyen, Brian T; Clark, Ronald J; Zhu, Lei

    2011-09-07

    mediating a 2-picolylazide-involved AAC reaction than the fully reduced Cu(OAc)(2). Finally, the discontinuous kinetic behavior that has been observed by us and others in copper(I/II)-mediated AAC reactions is explained by the likely catalyst disintegration during the course of a relatively slow reaction. Complementing the prior mechanistic conclusions drawn by other investigators, which primarily focus on the copper(I)/alkyne interactions, we emphasize the kinetic significance of copper(I/II)/azide interaction. This work not only provides a mechanism accounting for the fast Cu(OAc)(2)-mediated AAC reactions involving chelating azides, which has apparent practical implications, but suggests the significance of mixed-valency dinuclear copper species in catalytic reactions where two copper centers carry different functions.

  12. Experimental Investigation on the Mechanism of Chelation-Assisted, Copper(II) Acetate-Accelerated Azide-Alkyne Cycloaddition

    PubMed Central

    Kuang, Gui-Chao; Guha, Pampa M.; Brotherton, Wendy S.; Simmons, J. Tyler; Stankee, Lisa A.; Nguyen, Brian T.; Clark, Ronald J.; Zhu, Lei

    2011-01-01

    mediating a 2-picolylazide-involved AAC reaction than the fully reduced Cu(OAc)2. Finally, the discontinuous kinetic behavior that has been observed by us and others in copper(I/II)-mediated AAC reactions is explained by the likely catalyst disintegration during the course of a relatively slow reaction. Complementing the prior mechanistic conclusions drawn by other investigators which primarily focus on the copper(I)/alkyne interactions, we emphasize the kinetic significance of copper(I/II)/azide interaction. This work not only provides a mechanism accounting for the fast Cu(OAc)2-mediated AAC reactions involving chelating azides, which has apparent practical implications, but suggests the significance of mixed-valency dinuclear copper species in catalytic reactions where two copper centers carry different functions. PMID:21809811

  13. Flight investigation of natural laminar flow on the Bellanca Skyrocket II

    NASA Technical Reports Server (NTRS)

    Holmes, B. J.; Obara, C. J.; Gregorek, G. M.; Hoffman, M. J.; Freuhler, R. J.

    1983-01-01

    Two major concerns have inhibited the use of natural laminar flow (NLF) for viscous drag reduction on production aircraft. These are the concerns of achieveability of NLF on practical airframe surfaces, and maintainability in operating environments. Previous research in this area left a mixture of positive and negative conclusions regarding these concerns. While early (pre-1950) airframe construction methods could not achieve NLF criteria for waviness, several modern construction methods (composites for example) can achieve the required smoothness. This paper presents flight experiment data on the achieveability and maintainability of NLF on a high-performance, single-propeller, composite airplane, the Bellanca Skyrocket II. The significant contribution of laminar flow to the performance of this airplane was measured. Observations of laminar flow in the propeller slipstream are discussed, as are the effects of insect contamination on the wing. These observations have resulted in a new appreciation of the operational feasibility for achieving and maintaining NLF on modern airframe surfaces.

  14. Paleotectonic investigations of the Mississippian System in the United States: Parts I and II

    USGS Publications Warehouse

    Craig, Lawrence C.; Connor, Carol Waite; Others,

    1979-01-01

    This professional paper is the fifth in a series of paleotectonic studies each covering a geologic system in the conterminous United States. Part I provides a region-by-region discussion of data concerning the Mississippian System and an explanation and documentation for the maps and sections contained in part III. Part II of the paper provides a summary of the Mississippian System, presents interregional interpretations permitted by this study, and includes sections on notable features of the system. The maps contained in the separate case as part III may be divided into two groups: (1) a sequence of factual or basic maps that shows, with a minimum of interpretation, the Mississippian System as it occurs today, and (2) interpretive maps that attempt a reasonable reconstruction of the original extent of the system, its tectonics, environment, and geography.

  15. Complex formation of Sn(II) with glycine: an IR, DTA/TGA and DFT investigation.

    PubMed

    Novikova, Galina V; Petrov, Alexander I; Staloverova, Natalya A; Samoilo, Alexander S; Dergachev, Ilya D; Shubin, Alexander A

    2015-01-25

    The novel Sn(Gly)2⋅H2O complex compound has been synthesized and characterized by TGA, IR and Raman spectroscopy. Molecular spectroscopy and ab initio simulation have given the evidence of glycine molecule being coordinated to Sn(II) as bidentate chelating ligand by oxygen atom of carboxyl group and nitrogen atom of amino group. Water molecule is bonded with amino and carboxylic groups by hydrogen bonds in the out sphere. The M06, TPSS, TPSSm, TPSSh and revTPSS density functionals have been tested for calculation of structural and vibrational data. The vibrational assignment of experimental IR and Raman and simulated spectra has been carried out. The TPSS and TPSSm density functionals and Def2-TZVP basis set have provided the most accurate results. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Investigations about Starting Cracks in DC-Casting of 6063-Type Billets Part II: Modelling Results

    NASA Astrophysics Data System (ADS)

    Jensen, E. K.; Schneider, W.

    Influence on starting crack tendency of varying a number of casting parameters has been studied by experiments, Part I (1), and by model calculations, Part II. Both studies point to starting block shape as a most important single factor in controlling starting cracks. By using the thermal model ALSIM-2 in analysing initial experimental results, the variable heat transfer towards the starting block was determined. This made possible a satisfactory model analysis of the starting phase and likewise the formulation of a useful cracking concept. Thus by using calculated and measured liquid pool depth curve in the starting phase of casting as a basis, an effective starting block shape was found. This new shape practically eliminates the starting crack problems in extrusion billets of the AA6063 type alloys.

  17. Investigation of edge ExB sheared flow development in the TJ-II stellarator

    NASA Astrophysics Data System (ADS)

    Pedrosa, M. Angeles; Alonso, Arturo; Chmyga, Alexander A.; Eliseev, Leonid; Estrada, Teresa; Krupnik, Ludmila; Melnikov, Alexander V.; Orozco, Roberto Octavio; Zweben, Stewart J.

    2005-10-01

    Experiments carried out by means of Langmuir probes in the TJ-II stellarator have shown that above a plasma density threshold the level of turbulence decreases with a concomitant development of ExB perpendicular sheared flow (i.e. naturally occurring shear layer). The effect of density on sheared flows has been observed in different plasma magnetic configurations and regimes [1, 2]. The reversal in the ExB rotation has been 2-D visualized using Ultra Fast Speed cameras. Estimated velocity of observed blobs, rotating predominantly in the perpendicular direction, is in the range of 10^3--10^4 m/s. Heavy Ion Beam Probe and reflectometry measurements also show a strong dependence of edge radial electric fields and plasma rotation with plasma density. [1] C. Hidalgo et al., Phys. Rev. E 70 (2004) 067402. [2] M.A. Pedrosa et al., Plasma Phys. Control. Fusion 47 (2005) 777.

  18. Speech Production in Parkinson's Disease: II. Acoustic and Electropalatographic Investigation of Sentence, Word and Segment Durations

    ERIC Educational Resources Information Center

    McAuliffe, Megan J.; Ward, Elizabeth C.; Murdoch, Bruce E.

    2006-01-01

    Previous investigations employing electropalatography (EPG) have identified articulatory timing deficits in individuals with acquired dysarthria. However, this technology is yet to be applied to the articulatory timing disturbance present in Parkinson's disease (PD). As a result, the current investigation aimed to use EPG to comprehensively…

  19. Liquid-crystalline dendrimer Cu(II) complexes and Cu(0) nanoclusters based on the Cu(II) complexes: An electron paramagnetic resonance investigation

    NASA Astrophysics Data System (ADS)

    Domracheva, N. E.; Mirea, A.; Schwoerer, M.; Torre-Lorente, L.; Lattermann, G.

    2007-07-01

    New nanostructured materials, namely, the liquid-crystalline copper(II) complexes that contain poly(propylene imine) dendrimer ligands of the first (ligand 1) and second (ligand 2) generations and which have a columnar mesophase and different copper contents (x = Cu/L), are investigated by EPR spectroscopy. The influence of water molecules and nitrate counterions on the magnetic properties of complex 2 (x = 7.3) is studied. It is demonstrated that water molecules can extract some of the copper ions from dendrimer complexes and form hexaaqua copper complexes with free ions. The dimer spectra of fully hydrated complex 2 (x = 7.3) are observed at temperatures T < 10 K. For this complex, the structure is identified and the distance between the copper ions is determined. It is shown that the nitrate counterion plays the role of a bridge between the hexaaqua copper(II) complex and the dendrimer copper(II) complex. The temperature-induced valence tautomerism attended by electron transport is revealed for the first time in blue dendrimer complexes 1 (x = 1.9) with a dimer structure. The activation energy for electron transport is estimated to be 0.35 meV. The coordination of the copper ion site (NO4) and the structural arrangement of green complexes 1 (x = 1.9) in the columnar mesophase are determined. Complexes of this type form linear chains in which nitrate counterions serve as bridges between copper centers. It is revealed that green complexes 1 (x = 1.9) dissolved in isotropic inert solvents can be oriented in the magnetic field (B 0 = 8000 G). The degree of orientation of these complexes is rather high (S z = 0.76) and close to that of systems with a complete ordering (S z = 1) in the magnetic field. Copper(0) nanoclusters prepared by reduction of complex 2 (x = 7.3) in two reducing agents (NaBH4, N2H4 · H2O) are examined. A model is proposed for a possible location of Cu(0) nanoclusters in a dendrimer matrix.

  20. Systematical investigation of binding interaction between novel ruthenium(II) arene complex with curcumin analogs and ctDNA.

    PubMed

    Huang, Shan; Liang, Yu; Huang, Chusheng; Su, Wei; Lei, Xiaolin; Liu, Yi; Xiao, Qi

    2016-11-01

    In this study, the interaction between a novel ruthenium(II) arene complex with curcumin analogs and calf thymus DNA (ctDNA) was investigated systematically by viscosity measurement, the DNA melting approach, multispectroscopic techniques and electrochemical methods. The absorption spectra of the ctDNA-drug complex showed a slight red shift and a weak hypochromic effect. The relative viscosity and melting temperature of ctDNA increased on addition of the drug. The evidence obtained from fluorescence competitive experiments indicated that the binding mode of the drug with ctDNA was intercalative. Using acridine orange (AO) as a fluorescence probe, the drug statically quenched the fluorescence of the ctDNA-AO complex, and hydrogen bonding and van der Waals interactions played vital roles in the binding interaction between the drug and ctDNA. The influences of ionic strength, chemical denaturants and pH on the binding interaction were also investigated. Circular dichroism and Fourier transform infrared spectra suggested that this drug might bond with the G-C base pairs of ctDNA and the right-handed B-form helicity of ctDNA remained after drug binding. The intercalative binding between the drug and ctDNA was further investigated using electrochemical techniques. All these results suggested that the biological activity of ctDNA was affected by ruthenium(II) arene complex with curcumin analogs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. a Gas Phase Investigation of CuOH(H_2O)+ and Cu(II) Oligoglycine Water Oxidation Catalysts

    NASA Astrophysics Data System (ADS)

    Marsh, Brett; Zhou, Jia; Garand, Etienne

    2014-06-01

    The abundance of copper and copper compounds within the crust of the Earth and the well characterized coordination chemistry of copper species has led to investigation of copper as a catalyst for several different chemical reactions. Among the most notable of these has been the application of copper containing compounds to water oxidation. The chemistry used in this reaction has thus far been dominated by expensive materials containing the rare metals ruthenium or iridium. In this presentation we study several copper species which have attracted interest in this field including CuOH(H_2O)n+ clusters and Cu(II) oligoglycine complexes. We find that in the case of CuOH(H_2O)n+ clusters that the undercoordinated CuOH(H_2O)+ cluster has a strong affinity towards activating D2 while the higher coordinated CuOH(H_2O)2+ and CuOH(H_2O)3+ clusters show no propensity for the activation of D2. In the case of the Cu(II) oligoglycine complexes we find that the charge environment strongly affects the diagnostic CO stretch frequencies, creating a clear spectroscopic fingerprint for assessing the charge and interactions within these systems. Despite the small size (6-12 atoms) of the CuOH(H_2O)n+ clusters electronic structure methods including DFT and MP2 give poor agreement with the experimental results while DFT calculations on the relatively large Cu(II) oligoglycine species show excellent agreement with experiment.

  2. An investigation of long-distance propagation of gravity waves under CAWSES India Phase II Programme

    NASA Astrophysics Data System (ADS)

    Parihar, N.; Taori, A.

    2015-05-01

    Coordinated measurements of airglow features from the mesosphere-lower thermosphere (MLT) region were performed at Allahabad (25.5° N, 81.9° E) and Gadanki (13.5° N, 79.2° E), India to study the propagation of gravity waves in 13-27° N latitude range during the period June 2009 to May 2010 under CAWSES (Climate And Weather of Sun Earth System) India Phase II Programme. At Allahabad, imaging observations of OH broadband emissions and OI 557.7 nm emission were made using an all-sky imager, while at Gadanki photometric measurements of OH (6, 2) Meinel band and O2 (0, 1) Atmospheric band emissions were carried out. On many occasions, the nightly observations reveal the presence of similar waves at both locations. Typically, the period of observed similar waves lay in the 2.2-4.5 h range, had large phase speeds (~ 77-331 m s-1) and large wavelengths (~ 1194-2746 km). The images of outgoing long-wave radiation activity of the National Oceanic and Atmospheric Administration (NOAA) and the high-resolution infrared images of KALPANA-1 satellite suggest that such waves possibly originated from some nearby convective sources. An analysis of their propagation characteristics in conjunction with SABER/TIMED temperature profiles and Horizontal Wind Model (HWM 2007) wind estimates suggest that the waves propagated over long distances (~ 1200-2000 km) in atmospheric ducts.

  3. Investigating the Apoptosis Ability of Ethylenediamine 8-Hydroxyquinolinato Palladium (II) Complex

    PubMed Central

    Mansouri-Torshizi, Hassan; Rezaei, Elham; Kamranfar, Farzaneh; Heidari Majd, Mostafa

    2016-01-01

    Purpose: High solubility, low renal toxicity and apoptosis-inducing ability of palladium complexes are the reasons for their synthesis. Methods: In vitro cytotoxic study of previously synthesized [Pd(en)(8HQ)]NO3 , was carried out on breast cancer MCF-7 cell lines and prostate cancer DU145 cell lines. DNA fragmentation indicative of apoptotic was also evaluated by TUNEL assay on DU145 cell line. Results: FT-IR spectra of final complex confirmed the existence of chelating ligands. The DU145 cells unlike the MCF-7 cells, demonstrated the significant influence of the Pd (II) complex. The IC50 values of [Pd(en)(8HQ)]NO3 and cisplatin on DU145 cells were 27 and 8.3 μM, respectively. Moreover, nearly 38% apoptosis was evident in DU145 cells after treatment with [Pd(en)(8HQ)]NO3. Conclusion: [Pd(en)(8HQ)]NO3 has great potential in DNA binding and induction of apoptosis; thus it can be used in the future against prostate cancer. PMID:27766230

  4. New investigations of the guanine trichloro cuprate(II) complex crystal

    NASA Astrophysics Data System (ADS)

    Fabijanić, Ivana; Matković-Čalogović, Dubravka; Pilepić, Viktor; Ivanišević, Irena; Mohaček-Grošev, Vlasta; Sanković, Krešimir

    2017-01-01

    Crystals of the guanine trichloro cuprate(II) complex, (HGua)2[Cu2Cl6]·2H2O (HGua = protonated guanine), were prepared and analysed by spectroscopic (IR, Raman) and computational methods. A new single-crystal X-ray diffraction analysis was conducted to obtain data with lower standard uncertainties than those in the previously published structure. Raman and IR spectroscopy and quantum-mechanical analysis gave us new insight into the vibrational states of the (HGua)2[Cu2Cl6]·2H2O crystal. The vibrational spectra of the crystal were assigned by performing a normal coordinate analysis for a free dimer with a centre of inversion as the only symmetry element. The stretching vibration observed at 279 cm-1 in the infrared spectrum corresponds to the N-Cu bond. The noncovalent interaction (NCI) plots and quantum theory of atoms in molecules (QTAIM) analysis of the electron density obtained from periodic DFT calculations elucidated the interactions that exist within the crystal structure. Closed-shell ionic attractions, as well as weak and medium strength hydrogen bonds, prevailed in the crystal packing.

  5. Investigation of HV/HR-CMOS technology for the ATLAS Phase-II Strip Tracker Upgrade

    NASA Astrophysics Data System (ADS)

    Fadeyev, V.; Galloway, Z.; Grabas, H.; Grillo, A. A.; Liang, Z.; Martinez-Mckinney, F.; Seiden, A.; Volk, J.; Affolder, A.; Buckland, M.; Meng, L.; Arndt, K.; Bortoletto, D.; Huffman, T.; John, J.; McMahon, S.; Nickerson, R.; Phillips, P.; Plackett, R.; Shipsey, I.; Vigani, L.; Bates, R.; Blue, A.; Buttar, C.; Kanisauskas, K.; Maneuski, D.; Benoit, M.; Di Bello, F.; Caragiulo, P.; Dragone, A.; Grenier, P.; Kenney, C.; Rubbo, F.; Segal, J.; Su, D.; Tamma, C.; Das, D.; Dopke, J.; Turchetta, R.; Wilson, F.; Worm, S.; Ehrler, F.; Peric, I.; Gregor, I. M.; Stanitzki, M.; Hoeferkamp, M.; Seidel, S.; Hommels, L. B. A.; Kramberger, G.; Mandić, I.; Mikuž, M.; Muenstermann, D.; Wang, R.; Zhang, J.; Warren, M.; Song, W.; Xiu, Q.; Zhu, H.

    2016-09-01

    ATLAS has formed strip CMOS project to study the use of CMOS MAPS devices as silicon strip sensors for the Phase-II Strip Tracker Upgrade. This choice of sensors promises several advantages over the conventional baseline design, such as better resolution, less material in the tracking volume, and faster construction speed. At the same time, many design features of the sensors are driven by the requirement of minimizing the impact on the rest of the detector. Hence the target devices feature long pixels which are grouped to form a virtual strip with binary-encoded z position. The key performance aspects are radiation hardness compatibility with HL-LHC environment, as well as extraction of the full hit position with full-reticle readout architecture. To date, several test chips have been submitted using two different CMOS technologies. The AMS 350 nm is a high voltage CMOS process (HV-CMOS), that features the sensor bias of up to 120 V. The TowerJazz 180 nm high resistivity CMOS process (HR-CMOS) uses a high resistivity epitaxial layer to provide the depletion region on top of the substrate. We have evaluated passive pixel performance, and charge collection projections. The results strongly support the radiation tolerance of these devices to radiation dose of the HL-LHC in the strip tracker region. We also describe design features for the next chip submission that are motivated by our technology evaluation.

  6. Investigation of the Iron(II) Release Mechanism of Human H-Ferritin as a Function of pH.

    PubMed

    Sala, Davide; Ciambellotti, Silvia; Giachetti, Andrea; Turano, Paola; Rosato, Antonio

    2017-09-25

    We investigated the kinetics of the release of iron(II) ions from the internal cavity of human H-ferritin as a function of pH. Extensive molecular dynamics simulations of the entire 24-mer ferritin provided atomic-level information on the release mechanism. Double protonation of His residues at pH 4 facilitates the removal of the iron ligands within the C3 channel through the formation of salt bridges, resulting in a significantly lower release energy barrier than pH 9.

  7. Investigation of the performance of an MoS2/I-/I2/C electrochemical solar cell

    NASA Astrophysics Data System (ADS)

    Audas, R.; Irwin, J. C.

    1981-11-01

    The performance of an electrochemical solar cell with a single crystal of MoS2 in an I(-)/I2 electrolyte has been investigated. An efficiency greater than 5% has been obtained by carefully cleaving the crystal to ensure a good quality surface, and by optimizing the electrolyte concentration. The cell performance has been compared to the predictions of a phenomenological model that incorporates a term representing a diffusion overvoltage. Excellent agreement with the experimental results has been obtained with two free parameters, representing the shunt and series resistance of the cell.

  8. Investigation of aerosol effects on shallow marine convection - Lidar measurements during NARVAL-I and NARVAL-II

    NASA Astrophysics Data System (ADS)

    Groß, Silke; Wirth, Martin; Gutleben, Manuel; Ewald, Florian; Kiemle, Christoph; Kölling, Tobias; Mayer, Bernhard

    2017-04-01

    Clouds and aerosols have a large impact on the Earth's radiation budget by scattering and absorption of solar and terrestrial radiation. Furthermore aerosols can modify cloud properties and distribution. Up to now no sufficient understanding in aerosol-cloud interaction and in climate feedback of clouds is achieved. Especially shallow marine convection in the trade wind regions show large uncertainties in climate feedback. Thus a better understanding of these shallow marine convective clouds and how aerosols affect these clouds, e.g. by changing the cloud properties and distribution, is highly demanded. During NARVAL-I (Next-generation airborne remote-sensing for validation studies) and NARVAL-II a set of active and passive remote sensing instruments, i.e. a cloud radar, an aerosol and water vapor lidar system, microwave radiometer, a hyper spectral imager (NARVAL-II only) and radiation measurements, were installed on the German research aircraft HALO. Measurements were performed out of Barbados over the tropical North-Atlantic region in December 2013 and August 2016 to study shallow trade wind convection as well as its environment in the dry and wet season. While no or only few aerosol layers were observed above the marine boundary layer during the dry season in December 2013, part of the measurement area was influenced by high aerosol load caused by long-range transport of Saharan dust during the NARVAL-II measurements in August 2016. Measurement flights during NARVAL-II were conducted the way that we could probed aerosol influenced regions as well as areas with low aerosol load. Thus the measurements during both campaigns provide the opportunity to investigate if and how the transported aerosol layers change the distribution and formation of the shallow marine convection by altering their properties and environment. In our presentation we will focus on the lidar measurements performed during NARVAL-I and NARVAL-II. We will give an overview of the measurements

  9. Low-temperature synthesis of SmFeAsO0.7F0.3 - δ wires with a high transport critical current density

    NASA Astrophysics Data System (ADS)

    Wang, Lei; Qi, Yanpeng; Wang, Dongliang; Gao, Zhaoshun; Zhang, Xianping; Zhang, Zhiyu; Wang, Chunlei; Ma, Yanwei

    2010-07-01

    Ag-sheathed SmFeAsO0.7F0.3 - δ (Sm-1111) superconducting wires were prepared by a one-step solid state reaction at temperatures as low as 850-900 °C, instead of commonly used temperatures of 1150-1250 °C. The x-ray diffraction pattern of the as-sintered samples is well indexed on the basis of the tetragonal ZrCuSiAs-type structure. We characterized the transport critical current density Jc of the SmFeAsO0.7F0.3 - δ wires in increasing and subsequently decreasing fields, by a resistive four-probe method. A transport Jc as high as ~ 1300 A cm - 2 at 4.2 K and self-field has been observed for the first time in Sm-1111 type polycrystalline superconductors. The Jc also shows a rapid depression in small applied fields as well as a magnetic-history dependence, indicating weak-linked grain boundaries. The low-temperature synthesis method can be very beneficial for fabricating the RE-1111 iron oxypnictides in a convenient and safe way.

  10. Pressure-induced phase transition in La1–xSmxO0.5F0.5BiS2

    DOE PAGES

    Fang, Y.; Yazici, D.; White, B. D.; ...

    2015-09-15

    Electrical resistivity measurements on La1–xSmxO0.5F0.5BiS2 (x = 0.1, 0.3, 0.6, 0.8) have been performed under applied pressures up to 2.6 GPa from 2 K to room temperature. The superconducting transition temperature Tc of each sample significantly increases at a Sm-concentration dependent pressure Pt, indicating a pressure-induced phase transition from a low-Tc to a high-Tc phase. At ambient pressure, Tc increases dramatically from 2.8 K at x = 0.1 to 5.4 K at x = 0.8; however, the Tc values at P > Pt decrease slightly with x and Pt shifts to higher pressures with Sm substitution. In the normal state,more » semiconducting-like behavior is suppressed and metallic conduction is induced with increasing pressure in all of the samples. Furthermore, these results suggest that the pressure dependence of Tc for the BiS2-based superconductors is related to the lattice parameters at ambient pressure and enable us to estimate the evolution of Tc for SmO0.5F0.5BiS2 under pressure.« less

  11. Studies on the mechanism of oxidative phosphorylation: effects of specific F0 modifiers on ligand-induced conformation changes of F1.

    PubMed

    Matsuno-Yagi, A; Yagi, T; Hatefi, Y

    1985-11-01

    Aurovertin is a fluorescent antibiotic that binds to the catalytic beta subunits of the mitochondrial F1-ATPase and inhibits ATP synthesis and hydrolysis. ATP, ADP, and membrane energization in submitochondrial particles (SMP) alter the fluorescence of F1-bound aurovertin. These fluorescence changes are considered to be in response to the conformation changes of F1-ATPase. This paper shows that the ATP-induced fluorescence change of aurovertin bound to SMP or complex V (purified ATP synthase complex F0-F1) is inhibited when these preparations are pretreated with oligomycin or N,N'-dicyclohexylcarbodiimide (DCCD). This inhibition is not seen with isolated F1-ATPase. These and other results have suggested that modifications of the DCCD-binding protein in the membrane sector (F0) of the ATP synthase complex are communicated to F1, thereby altering the binding characteristics of ATP to the beta subunits. By analogy, it is proposed that modifications (e.g., protonation/deprotonation) of the DCCD-binding protein effected by protonic energy alter the conformation of F1 and bring about the substrate/product binding changes that appear to be essential features of the mechanism and regulation of oxidative phosphorylation.

  12. Development of a novel biosensor based on F(0)F(1)-ATPase for the detection of 2-dodecylcyclobutanone in irradiated beef.

    PubMed

    Zhao, Yueliang; Ha, Yiming; Yue, Jiachang; Wang, Feng

    2015-12-01

    A novel biosensor regulated by the rotator of F0F1-ATPase was developed to analyze 2-dodecylcyclobutanone (2-DCB) to detect γ-ray irradiated beef rapidly. The biosensor was assembled by conjugating 2-DCB monoclonal antibodies with the "rotator" ε-subunit of F0F1-ATPase within chromatophores through an ε-subunit monoclonal antibody-biotin-avidin-biotin linker. The limit of detection (LOD) of 2-DCB was approximately 10(-8) μg/mL. The recovery ratio of 2-DCB from ground beef patties ranged from 75.1% to 116.4%. The intra-assay and inter-assay coefficients of variation were both <15.0%. The proposed method was validated by gas chromatography-mass spectrometry with high correlation. The biosensor was used to detect 2-DCB in ground beef patties with different fat contents (10%, 20%, and 30%) irradiated at 0.5, 1.0, 3.0, 5.0, and 7.0 kGy. The 2-DCB concentration linearly increased with the radiation dose in all the beef samples. 2-DCB concentration increased with fat levels in the three samples.

  13. Role of scalar dibaryon and f0(500 ) in the isovector channel of low-energy neutron-proton scattering

    NASA Astrophysics Data System (ADS)

    Deinet, Werner; Teilab, Khaled; Giacosa, Francesco; Rischke, Dirk H.

    2016-10-01

    We calculate the total and the differential cross section for n p scattering at low energies in the isospin I =1 channel within the so-called extended linear sigma model. This model contains conventional (pseudo)scalar and (axial-)vector mesons, as well as the nucleon and its chiral partner within the mirror assignment. In order to obtain good agreement with experimental data analysis results we need to consider two additional resonances: the lightest scalar state f0(500 ) and a dibaryon state with quantum numbers I =1 ,JP=0+ (also known as S10 resonance). The resonance f0(500 ) is coupled to nucleons in a chirally invariant way through the mirror assignment and is crucial for a qualitatively correct description of the shape of the differential cross section. On the other hand, the dibaryon is exchanged in the s channel and is responsible of the large cross section close to threshold. We compare our results to data analysis results performed by the said program of the CNS Data Analysis Center (in the following "said results").

  14. Multiple and reversible hydrogenases for hydrogen production by Escherichia coli: dependence on fermentation substrate, pH and the F(0)F(1)-ATPase.

    PubMed

    Trchounian, Karen; Poladyan, Anna; Vassilian, Anait; Trchounian, Armen

    2012-01-01

    Molecular hydrogen (H(2)) can be produced via hydrogenases during mixed-acid fermentation by bacteria. Escherichia coli possesses multiple (four) hydrogenases. Hydrogenase 3 (Hyd-3) and probably 4 (Hyd-4) with formate dehydrogenase H (Fdh-H) form two different H(2)-evolving formate hydrogen lyase (FHL) pathways during glucose fermentation. For both FHL forms, the hycB gene coding small subunit of Hyd-3 is required. Formation and activity of FHL also depends on the external pH ([pH](out)) and the presence of formate. FHL is related with the F(0)F(1)-ATPase by supplying reducing equivalents and depending on proton-motive force. Two other hydrogenases, 1 (Hyd-1) and 2 (Hyd-2), are H(2)-oxidizing enzymes during glucose fermentation at neutral and low [pH](out). They operate in a reverse, H(2)-producing mode during glycerol fermentation at neutral [pH](out). Hyd-1 and Hyd-2 activity depends on F(0)F(1). Moreover, Hyd-3 can also work in a reverse mode. Therefore, the operation direction and activity of all Hyd enzymes might determine H(2) production; some metabolic cross-talk between Hyd enzymes is proposed. Manipulating of different Hyd enzymes activity is an effective way to enhance H(2) production by bacteria in biotechnology. Moreover, a novel approach would be the use of glycerol as feedstock in fermentation processes leading to H(2) production, reduced fuels and other chemicals with higher yields than those obtained by common sugars.

  15. Molecular structures, charge distributions, and vibrational analyses of the tetracoordinate Cu(II), Zn(II), Cd(II), and Hg(II) bromide complexes of p-toluidine investigated by density functional theory in comparison with experiments

    NASA Astrophysics Data System (ADS)

    Bardakçı, Tayyibe; Kumru, Mustafa; Altun, Ahmet

    2016-07-01

    The Cu(II), Zn(II), Cd(II), and Hg(II) bromide complexes of p-toluidine have been studied with B3LYP calculations by using def2-TZVP basis set at the metal atoms and using def2-TZVP and 6-311G+(d,p) basis sets at the remaining atoms. Both basis set combinations give analogous results, which validate the use of quickly converging 6-311G+(d,p) basis set in future studies. The molecular structures, atomic charge and spin distributions, and harmonic vibrational frequencies of the complexes have been calculated. The Zn, Cd and Hg complexes have been found to have distorted tetrahedral environments around the metal atoms whereas Cu complex has a square planar geometry. The NBO charge analysis have been found more accurate and less misleading compared with the Mulliken scheme. The present vibrational spectra calculations allow accurate assignment of the vibrational bands, which otherwise assigned tentatively in previous experimental-only studies.

  16. MarsSedEx I and II: Experimental investigation of gravity effects on sedimentation on Mars

    NASA Astrophysics Data System (ADS)

    Kuhn, N. J.; Kuhn, B.; Gartmann, A.

    2014-12-01

    Sorting of sedimentary rocks is a proxy for the environmental conditions at the time of deposition, in particular the runoff that moved and deposited the material forming the rocks. Settling of sediment is strongly influenced by the gravity of a planetary body. As a consequence, sorting of a sedimentary rock varies with gravity for a given depth and velocity of surface runoff. Theoretical considerations for spheres indicate that sorting is less uniform on Mars than on Earth for runoff of identical depth. The effects of gravity on flow hydraulics limit the use of common, semi-empirical models developed to simulate particle settling in terrestrial environments, on Mars. Assessing sedimentation patterns on Mars, aimed at identifying strata potentially hosting traces of life, is potentially affected by such uncertainties. Using first-principle approaches, e.g. through Computational Fluid Dynamics, for calculating settling velocities on other planetary bodies requires a large effort and is limited by the values of boundary conditions, e.g. the shape of the particle. The degree of uncertainty resulting from the differences in gravity on Earth and Mars was therefore tested during three reduced-gravity flights, the MarsSedEx I and II missions, conducted in November 2012 and 2013. Nine types of sediment, ranging in size, shape and density were tested in custom-designed settling tubes during parabolas of Martian gravity lasting 20 to 25 seconds. Based on the observed settling velocities, the uncertainties of empirical relationships developed on Earth to assess particle settling on Mars are discussed. In addition, the potential effects of reduced gravity on patterns of erosion, transport and sorting of sediment, including the implications for identifying strata bearing traces of past life on are examined.

  17. A large Turkish kindred with syndactyly type II (synpolydactyly). 1. Field investigation, clinical and pedigree data.

    PubMed Central

    Sayli, B S; Akarsu, A N; Sayli, U; Akhan, O; Ceylaner, S; Sarfarazi, M

    1995-01-01

    A very large Turkish family with syndactyly type II (synpolydactyly (SPD)) is described, which originated from and is mainly concentrated in the village of Derbent, Afyon. The kindred consists of 425 subjects over seven generations, of whom 182 are affected. It appears that a founder effect in this village has led to this extensive kindred. This condition is inherited as an autosomal dominant trait with variable expressivity and an estimated penetrance of 96%. Penetrance is different between the upper (96%) and lower (69.5%) extremities. No excess of affected males or females or other associated features were documented in this condition. Variations in the involvement of one or both hands, upper or lower extremities, bone and soft tissue, as well as variation in the affected subjects of two successive generations were documented. We also noted that metacarpal and metatarsal involvement and middle phalangeal hypoplasia of the feet are the consistent features of SPD and, therefore, should be considered as characteristic of this phenotype. We observed four different phenotypes in various branches of the Derbent kindred: (1) subjects presenting typical features of SPD; (2) subjects exhibiting both pre- and post-axial polydactyly simultaneously; (3) persons manifesting postaxial polydactyly type A; and (4) subjects born to two affected parents with severe hand and foot deformities that have not been previously described in any other SPD families (that is, homozygotes). A total of 27 affected offspring were born to two such affected parents, of whom seven are expected to be homozygous for the SPD gene. This group is presented in an accompanying paper in this issue of the Journal. A molecular study is currently under way to identify the chromosomal location of the defective gene. Images PMID:7666393

  18. Randomized Phase II Study Investigating Pazopanib Versus Weekly Paclitaxel in Relapsed or Progressive Urothelial Cancer.

    PubMed

    Jones, Robert J; Hussain, Syed A; Protheroe, Andrew S; Birtle, Alison; Chakraborti, Prabir; Huddart, Robert A; Jagdev, Satinder; Bahl, Amit; Stockdale, Andrew; Sundar, Santhanam; Crabb, Simon J; Dixon-Hughes, Judith; Alexander, Laura; Morris, Anna; Kelly, Caroline; Stobo, Jon; Paul, James; Powles, Thomas

    2017-06-01

    Purpose Two previous single-arm trials have drawn conflicting conclusions regarding the activity of pazopanib in urothelial cancers after failure of platinum-based chemotherapy. Patients and Methods This randomized (1:1) open-label phase II trial compared the efficacy of pazopanib 800 mg orally with paclitaxel (80 mg/m(2) days 1, 8, and 15 every 28 days) in the second-line setting. The primary end point was overall survival (OS). Results Between August 2012 and October 2014, 131 patients, out of 140 planned, were randomly assigned. The study was terminated early on the recommendation of the independent data monitoring committee because of futility. Final analysis after the preplanned number of deaths (n = 110) occurred after a median follow-up of 18 months. One hundred fifteen deaths had occurred at the final data extract presented here. Median OS was 8.0 months for paclitaxel (80% CI, 6.9 to 9.7 months) and 4.7 months for pazopanib (80% CI, 4.2 to 6.4 months). The hazard ratio (HR) adjusted for baseline stratification factors was 1.28 (80% CI, 0.99 to 1.67; one-sided P = .89). Median progression-free survival was 4.1 months for paclitaxel (80% CI, 3.0 to 5.6 months) and 3.1 months for pazopanib (80% CI, 2.7 to 4.6 months; HR, 1.09; 80% CI, 0.85 to 1.40; one-sided P = .67). Discontinuations for toxicity occurred in 7.8% and 23.1% for paclitaxel and pazopanib, respectively. Conclusion Pazopanib did not have greater efficacy than paclitaxel in the second-line treatment of urothelial cancers. There was a trend toward superior OS for paclitaxel.

  19. Spectroscopic investigations on Cu(II) ions doped in alkali lead borotellurite glasses

    NASA Astrophysics Data System (ADS)

    Murali, A.; Lakshmana Rao, J.

    1999-10-01

    Electron paramagnetic resonance, optical absorption spectra, Raman spectra and physical properties of copper(II) ions in (85-x/2)R2B4O7-xPbO-yCuO-(15-x/2- y)TeO2 (x = 0,10; y = 0.1-1.5; R = Li, Na or K) glasses were studied. EPR spectra of all the glasses show resonance peaks characteristic of Cu2+ ions. The number of spins participating in the resonance was measured as a function of temperature and the activation energy was calculated. From the EPR and density measurements, the ratio of number of copper ions in +2 state to the total copper ions (i.e., N2/NT) was calculated. The paramagnetic susceptibility was calculated from the EPR data at various temperatures and the Curie constant was calculated from the 1/icons/Journals/Common/chi" ALT="chi" ALIGN="TOP"/>-T graph. The optical absorption spectra of all the samples show a broad absorption band; the position of the band maxima varies from 14 500 to 12 700 cm-1 for glasses with different alkali ions. The optical energy gap Eopt and Urbach energy icons/Journals/Common/Delta" ALT="Delta" ALIGN="TOP"/> E were calculated for all the glass samples from their ultraviolet edges. The optical energy gap varies between 3.4 and 2.7 eV and increases from Li to K glasses. Also, it was observed that as copper ion concentration is increased, Eopt decreases while icons/Journals/Common/Delta" ALT="Delta" ALIGN="TOP"/> E increases. This was explained as due to change in non-bridging oxygen content. Raman spectra of three samples were recorded at room temperature. The bands were assigned as due to various groups of boron.

  20. Investigating the Early Stages of Photosystem II Assembly in Synechocystis sp. PCC 6803

    PubMed Central

    Boehm, Marko; Romero, Elisabet; Reisinger, Veronika; Yu, Jianfeng; Komenda, Josef; Eichacker, Lutz A.; Dekker, Jan P.; Nixon, Peter J.

    2011-01-01

    Biochemical characterization of intermediates involved in the assembly of the oxygen-evolving Photosystem II (PSII) complex is hampered by their low abundance in the membrane. Using the cyanobacterium Synechocystis sp. PCC 6803, we describe here the isolation of the CP47 and CP43 subunits, which, during biogenesis, attach to a reaction center assembly complex containing D1, D2, and cytochrome b559, with CP47 binding first. Our experimental approach involved a combination of His tagging, the use of a D1 deletion mutant that blocks PSII assembly at an early stage, and, in the case of CP47, the additional inactivation of the FtsH2 protease involved in degrading unassembled PSII proteins. Absorption spectroscopy and pigment analyses revealed that both CP47-His and CP43-His bind chlorophyll a and β-carotene. A comparison of the low temperature absorption and fluorescence spectra in the QY region for CP47-His and CP43-His with those for CP47 and CP43 isolated by fragmentation of spinach PSII core complexes confirmed that the spectroscopic properties are similar but not identical. The measured fluorescence quantum yield was generally lower for the proteins isolated from Synechocystis sp. PCC 6803, and a 1–3-nm blue shift and a 2-nm red shift of the 77 K emission maximum could be observed for CP47-His and CP43-His, respectively. Immunoblotting and mass spectrometry revealed the co-purification of PsbH, PsbL, and PsbT with CP47-His and of PsbK and Psb30/Ycf12 with CP43-His. Overall, our data support the view that CP47 and CP43 form preassembled pigment-protein complexes in vivo before their incorporation into the PSII complex. PMID:21339295

  1. Individualizing Instruction in Large Undergraduate Biology Laboratories. II. Computers and Investigation

    ERIC Educational Resources Information Center

    Norberg, Ann Marie

    1975-01-01

    Describes the following uses of computers in college biology laboratories: (1) to organize and analyze research data and (2) to simulate biological systems. Also being developed are computer simulations to systematically prepare students for independent investigations. (See also SE 515 092.) (LS)

  2. Thinking through Text Comprehension II: Analysis of Verbal and Investigative Repertoires

    ERIC Educational Resources Information Center

    Sota, Melinda; Leon, Marta; Layng, T. V. Joe

    2011-01-01

    Reading comprehension can be considered a complex human performance involving two integrated repertoires: a verbal repertoire and an investigative (generative) repertoire. This paper describes an analysis of these repertoires in terms which can ultimately inform the design of programs to teach them, using the analysis and design of Headsprout[R]…

  3. Geologic and seismologic investigations for Rocky Flats Plant. Volume II. Appendices. Final report

    SciTech Connect

    Not Available

    1981-07-01

    This volume contains the results of a seismic refraction study of the Ralston Reservoir area, soil stratigraphic investigations, unit descriptions, an analysis of geodetic data, experimental models, seismological evaluation, a seismicity survey of the Northern Golden Fault, historical data for the November 7, 1882 earthquake, and a dendrochronology study. (ACR)

  4. Architecture of Kepler's Multi-transiting Systems: II. New investigations with twice as many candidates

    SciTech Connect

    Fabrycky, Daniel C.; Lissauer, Jack J.; Ragozzine, Darin; Rowe, Jason F.; Steffen, Jason H.; Agol, Eric; Barclay, Thomas; Batalha, Natalie; Borucki, William; Ciardi, David R.; Ford, Eric B.; Gautier, Thomas N.; Geary, John C.; Holman, Matthew J.; Jenkins, Jon M.; Li, Jie; Morehead, Robert C.; Morris, Robert L.; Shporer, Avi; Smith, Jeffrey C.; Still, Martin; Van Cleve, Jeffrey

    2014-07-16

    Having discovered 885 planet candidates in 361 multiple-planet systems, Kepler has made transits a powerful method for studying the statistics of planetary systems. The orbits of only two pairs of planets in these candidate systems are apparently unstable. This indicates that a high percentage of the candidate systems are truly planets orbiting the same star, motivating physical investigations of the population. Pairs of planets in this sample are typically not in orbital resonances. However, pairs with orbital period ratios within a few percent of a first-order resonance (e.g. 2:1, 3:2) prefer orbital spacings just wide of the resonance and avoid spacings just narrow of the resonance. Finally, we investigate mutual inclinations based on transit duration ratios. We infer that the inner planets of pairs tend to have a smaller impact parameter than their outer companions, suggesting these planetary systems are typically coplanar to within a few degrees.

  5. Archaeological Investigations, Navigation Pool II, Upper Mississippi River Basin. Volume 2. Data File

    DTIC Science & Technology

    1984-01-01

    successful Contractor will be provided a set of detailed tract maps for their uise. Finally, note that the abandoned town of Peru, Iowa, talls partially...the principal investigator through the maintenance of employee time records, travel and equipment expenditures , payroll records, and other...Engineer Office, Rock Island, IL under the direction of Major C.L. Hall . These maps portray the pool conditions immediately prior to construction of the

  6. Investigating rare events with nonequilibrium work measurements. II. Transition and reaction rates.

    PubMed

    Moradi, Mahmoud; Sagui, Celeste; Roland, Christopher

    2014-01-21

    We present a formalism for investigating transition pathways and transition probabilities for rare events in biomolecular systems. The formalism is based on combining Transition Path Theory with the results of nonequilibrium work relations, and shows that the equilibrium and nonequilibrium transition rates are in fact related. Aside from its fundamental importance, this allows for the calculation of relative equilibrium reaction rates with driven nonequilibrium simulations such as Steered Molecular Dynamics. The workings of the formalism are illustrated with a few typical numerical examples.

  7. Investigation of the Hazards Posed by Chemical Vapors Released in Marine Operations - Phase II.

    DTIC Science & Technology

    1983-04-01

    at San Antonio, Texas . 307 U.S. COAST GUARDf SOUTHWEST RESEARCH INSTITUTE, SAN ANTONIO, TEXAS , USA UNIVERSITY OF TEXAS SCHOOL OF PUBLIC HEALTH, HOUSTON... TEXAS , USA SUBJECT CONSENT FOR PARTICIPATION IN AN INVESTIGATION OF "HAZARDS POSED BY CHEMICAL VAPORS RELEASED IN MARINE OPERATIONS: TASK V...write to the following persons: Dr. Stanley M. Pier Mr. William J. Astleford 5326 Dora Street Southwest Research Institute Houston, Texas , 77005, USA

  8. Cluster II Wideband (WBD) Plasma Wave Investigation Mission Operations and Data Analysis

    NASA Technical Reports Server (NTRS)

    Gurnett, Donald A.

    2004-01-01

    This Summary of Research is being submitted to NASA Goddard Space Flight Center. A summary of the significant accomplishments of the Cluster Wideband (WBD) Plasma Wave Investigation team achieved during the period of the grant, October 1,2000 through January 14, 2004, and a listing of all of the publications that resulted from work carried out under the grant is presented. Also included is a listing of the numerous public outreach activities that took place during the period of the grant in which the Cluster mission and Cluster WBD science were discussed.

  9. Investigation of heat transfer due to isothermal heater in irregular porous cavity: Part II

    NASA Astrophysics Data System (ADS)

    Azeem, Soudagar, Manzoor Elahi M.

    2017-07-01

    The present work is undertaken to investigate the effect of isothermal block placed at center of left vertical surface of porous cavity. The block is heated with isothermal temperature and right vertical surface of cavity is maintained at lowest temperature in domain. Finite element method is used to convert the governing equations into a simpler form. It is found that the heat transfer behavior for present case is different from that of the case when isothermal block is placed at bottom or top of the cavity.

  10. A renal protocol for all ages and all indications: mercapto-acetyl-triglycine (MAG3) with simultaneous injection of furosemide (MAG3-F0): a 17-year experience.

    PubMed

    Sfakianakis, George N; Sfakianaki, Efrosyni; Georgiou, Mike; Serafini, Aldo; Ezuddin, Shabbir; Kuker, Russ; Zilleruelo, Gaston; Strauss, Jose; Abitbol, Carolyn; Chandar, Jayanthi; Seeherunvong, Wacharee; Bourgoignie, Jacque; Roth, David; Leveillee, Raymond; Bird, Vincent G; Block, Norman; Gosalbez, Rafael; Labbie, Andrew; Guerra, Jorge J; Yrizarry, Jose

    2009-05-01

    Current clinical requirements mandate the existence of a renal diuretic protocol, which is fast and easy, applicable in all ages and for all indications, convenient for both the patient and the technologist, and provides diagnostic as well as prognostic information. Seventeen years ago a 25-minute protocol, after oral hydration, with no bladder catheterization, and simultaneous injection of mercapto-acetyl-triglycine (MAG(3)) and furosemide (MAG(3)-F(0)), was initiated. It initially was used for the evaluation of drainage and emerged as a protocol to also evaluate the renal parenchyma. Results of this protocol have been published individually, per clinical application. MAG(3)-F(0) was instrumental in the evaluation and prognosis of congenital disorders. For obstruction, in the newborn, an increasing renogram mandates intervention, whereas a downsloping one predicts spontaneous resolution. In children or adults, preoperatively or postoperatively, when the cortex was visualized and drained normally, there was no obstruction, even if urine was retained within a dilated collecting system or an extrarenal pelvis. For diseases of the renal parenchyma, the protocol enabled the diagnosis of acute pyelonephritis (APN) revealing the "regional parenchymal dysfunction," diagnostic of APN. Diffuse parenchymal diseases were characterized by increased residual cortical activity (RCA), and their progression was manifested as a deterioration of RCA. End-stage renal disease was characterized by lack of accumulation and retention. Trauma and leaks were identified with specific patterns. In renovascular hypertension (RVH), an increase in RCA after angiotension-converting enzyme inhibitors is diagnostic of RVH and prognostic of the beneficial effect of angioplasty on hypertension. In renal colic, stratification was possible into (1) complete or severe obstruction requiring immediate intervention, (2) mild obstruction allowing waiting, (3) spontaneous decompression (stunned kidney), and

  11. Heat Transfer Investigation of Air Flow in Microtubes-Part II: Scale and Axial Conduction Effects.

    PubMed

    Lin, Ting-Yu; Kandlikar, Satish G

    2013-03-01

    In this paper, the scale effects are specifically addressed by conducting experiments with air flow in different microtubes. Three stainless steel tubes of 962, 308, and 83 μm inner diameter (ID) are investigated for friction factor, and the first two are investigated for heat transfer. Viscous heating effects are studied in the laminar as well as turbulent flow regimes by varying the air flow rate. The axial conduction effects in microtubes are experimentally explored for the first time by comparing the heat transfer in SS304 tube with a 910 μm ID/2005 μm outer diameter nickel tube specifically fabricated using an electrodeposition technique. After carefully accounting for the variable heat losses along the tube length, it is seen that the viscous heating and the axial conduction effects become more important at microscale and the present models are able to predict these effects accurately. It is concluded that neglecting these effects is the main source of discrepancies in the data reported in the earlier literature.

  12. Investigational phosphodiesterase inhibitors in phase I and phase II clinical trials for Alzheimer's disease.

    PubMed

    Prickaerts, Jos; Heckman, Pim R A; Blokland, Arjan

    2017-09-01

    Phosphodiesterase (PDE) inhibitors improve signaling pathways in brain circuits by increasing intracellular cyclic adenosine monophosphate (cAMP) and/or cyclic guanosine monophosphate (cGMP). In the last decade, the first clinical studies investigating selective PDE inhibitors in Alzheimer's disease (AD) have been initiated, based on their positive effects on cognitive processes and neuroprotection in numerous animal studies. Areas covered: This article reviews the clinical studies investigating the pro-cognitive/neuroprotective effects of PDE inhibitors in patients with AD, as well as in age-associated memory impaired elderly and patients with mild cognitive impairment (MCI), the prodromal stage of AD. PDE inhibitors will also be discussed with respect to adverse effects including safety and tolerability. Expert opinion: The limited available data of clinical studies with PDE inhibitors tested in different populations of AD patients do not allow the drawing of any concrete conclusion yet. Currently, studies with a PDE3 (cilostazol) or PDE9 inhibitor (BI 409,306) are still ongoing in patients with MCI or AD, respectively. Studies with PDE4 inhibitors (HT-0712, roflumilast and BPN14770) in healthy elderly and elderly with age-associated memory impairments indicate that the optimum dose and/or inhibiting the most relevant PDE isoform hold great promise when tested in the appropriate population of patients with MCI or AD eventually.

  13. NMR investigation of dynamic processes in complexes of nickel(II) and zinc(II) with iminodiacetate, n-methyliminodiacetate and n-ethyliminodiacetate

    SciTech Connect

    Wagner, M.R.

    1985-11-01

    Analysis of oxygen-17 bulk water relaxation rates with an aqueous solution of 1:1 Ni(II):ida reveals that two rate-limiting processes are involved with solvent exchange. Analysis of carbon-13 longitudinal relaxation rates of the bis-ligand complexes with zinc(II) are used to determine molecular tumbling rates and methyl rotation rates. The carbon-13 transverse relaxation rates for the carbons in the bis-ligand complex with Ni(II) are adequately fitted to the Solomon-Bloembergen equation. Three carboxylate carbon peaks are seen with the /sup 13/C spectrum of the 1:2 Ni(II):ida complex, which coalesce into a single peak above about 360 K. The mechanism and rate of ligand exchange are determined for the complexes Zn(II)L/sub 2//sup -2/ (L = mida, eida) in aqueous solution by total lineshape analysis of the proton spectrum at 500 MHz.

  14. Melting of oxidized nickel ores in a barbotage unit: II. Experimental investigations

    NASA Astrophysics Data System (ADS)

    Starykh, R. V.; Pakhomov, R. A.

    2016-07-01

    The possibility of efficient processing of oxidized nickel ores (ONOs) to form ferronickel in a barbotage unit (liquid bath melting (LBM), Vanyukov furnace) is corroborated theoretically and experimentally. The processing of the ONOs of the Buruktal deposit with the formation of ferronickel under the conditions that model melting in a barbotage unit is subjected to laboratory investigations. Wet or dried ore and its reduced cinder are melted. It is shown that melting of the reduced cinder of ONO can result in the formation of nickel-rich (up to 40% Ni) ferronickel upon the extraction of more than 91% nickel from the raw materials at a residual nickel content of <0.1% in a slag. Direct melting of the ore results in the formation of ferronickel with at most 18% Ni and a low degree of nickel extraction into ferronickel, which has high sulfur, phosphorus, and carbon contents in this case.

  15. EXAFS investigations of Zn(II) in concentrated aqueous hydroxide solutions

    SciTech Connect

    Pandya, K.I.; Russell, A.E.; McBreen, J.; O`Grady, W.E.

    1995-08-03

    The structure of the Zn{sup 2+} species in concentrated aqueous solutions of NaOH, KOH, RbOH, and CsOH was investigated with extended X-ray absorption fine structure (EXAFS) spectroscopy. The results show that the Zn{sup 2+} species exist in a tetrahedral configuration with a Zn-O bond distance of 1.96 x 0.01 A, independent of the cation of the hydroxide electrolyte. No evidence for higher Zn-H{sub 2}O coordination shells, aggregation of the Zn(OH){sub 4}{sup 2} tetrahedra, or Zn-Zn interactions were found. The necessity of including the multiple-scattering contributions to obtain a complete and correct EXAFS analysis is clearly shown. 34 refs., 10 figs., 5 tabs.

  16. Kinetic and thermodynamic investigations of Pb(II) and Cd(II) adsorption on nanoscale organo-functionalized SiO₂-Al₂O₃.

    PubMed

    Jazi, M Boroumand; Arshadi, M; Amiri, M J; Gil, A

    2014-05-15

    This paper reports the preparation of three new Schiff base ligands modified SiO2-Al2O3 mixed oxide adsorbents, and their use for removal of Pb(II) and Cd(II) from aqueous solutions. Equilibrium and kinetic models for Pb(II) and Cd(II) sorption were applied by considering the effect of the contact time, initial Pb(II) and Cd(II) concentrations, effect of temperature, and initial pH. The contact time to attain equilibrium for maximum adsorption was 120 min. These heterogeneous Schiff base ligands were found to be effective adsorbents for the removal of heavy metal ions from solution, with Si/Al-pr-NH-et-N=pyridine-2-carbaldehyde having a high adsorption capacity for Pb(II) and Cd(II) ions from aqueous solution. The adsorption of heavy metal ions has been studied in terms of pseudo-first- and -second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherms models have also been used to the equilibrium adsorption data. The adsorption kinetics followed the mechanism of the pseudo-second-order equation for all systems studied, confirming chemical sorption as the rate-limiting step of adsorption mechanisms and not involving mass transfer in solution, which were confirmed by techniques of DS UV-vis and FT-IR. The thermodynamic parameters (ΔG, ΔH and ΔS) indicated that the adsorption of Pb(II) and Cd(II) ions were feasible, spontaneous and endothermic between 25 and 80°C. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Evaluation of some biological tests as parameters for microbial activities in soils. II. Field investigations.

    PubMed

    Abd-El-Malek, Y; Monib, M; Rizk, S G; Shehata, S M

    1976-01-01

    Investigations were designed to study the effect of certain factors on the microbial activities in soil. The parameters, used as an index of the microbial activities, were total bacterial counts, dehydrogenase activity, oxidation of organic carbon, and CO2 evolved/7 days. Bahteem Farm clay soil was examined for determining the effects of depth, type of fertilization, and crop rotation on the microbial activities. It appears that the microbial activities, as indicated by the tested parameters, were more pronounced in the surface 15 cm-layer than in the subsurface layer (15-30 cm). Results of all the parameters tested showed markedly higher increases with farmyard manure than with nitrogenous fertilizer and in the control, without significant differences between the latter two. Moreover, the time of sampling had no effect on the results obtained for all parameters. Different types of rotations did not exert significant variation in total bacterial counts, though more than one crop per year increased the organic carbon content of soil and mostly the dehydrogenase activity, whereas the evolution of CO2 tended to decrease. At Gabal el-Asfar Farm, the effect of irrigation with sewage effluent, for long periods, on the microbial activities of sandy soil was investigated. Sewage water stimulated the total bacteria, raised the dehydrogenase activity, the organic carbon, and the production of CO2. In North El Tahreer and Mariut Sectors, the effect of both the type and age of cultivation on the microbial activities in the calcareous soils were examined. Cultivation raised the figures of all the tested parameters progressively with time of cultivation. It was also noticed that crops exerted more beneficial effects on microbial activities than orchards, and the dehydrogenase test was the most reliable parameter to reveal this fact.

  18. Vortex dynamics and irreversibility line in optimally doped SmFeAsO0.8F0.2 from ac susceptibility and magnetization measurements

    NASA Astrophysics Data System (ADS)

    Prando, G.; Carretta, P.; de Renzi, R.; Sanna, S.; Palenzona, A.; Putti, M.; Tropeano, M.

    2011-05-01

    Ac susceptibility and static magnetization measurements were performed in the optimally doped SmFeAsO0.8F0.2 superconductor. The field-temperature phase diagram of the superconducting state was drawn, and, in particular, the features of the flux lines were derived. The dependence of the intragrain depinning energy on the magnetic field intensity was derived in the thermally activated flux-creep framework, enlightening a typical 1/H dependence in the high-field regime. The intragrain critical current density was extrapolated in the zero-temperature and zero-magnetic-field limit, showing a remarkably high value Jc0(0)~2×107 A/cm2, which demonstrates that this material is rather interesting for potential future technological applications.

  19. Role of the a0(980), f0(980) resonances in η → 3π from the Khuri-Treiman formalism

    NASA Astrophysics Data System (ADS)

    Moussallam, B.; Albaladejo, M.

    2016-11-01

    The chiral expansion of the η → 3π decay amplitude at NLO fails to reproduce the recent high accuracy measurements of the Dalitz plot parameters. We reconsider the idea of employing the chiral expansion in an unphysical region surrounding the Adler zero and then deducing the amplitude in the physical region using the Khuri-Treiman dispersive formalism. We further present an extension of this formalism which takes into account KK¯ inelastic rescattering effects and thus provides a realistic description of the double a0(980), f0(980) resonance effect. We evaluate how the influence of these resonances propagates down to the low-energy decay region and show that it is significant, in particular for the η → 3π0 decay, and improve the agreement of the predicted Dalitz plot parameters with experiment.

  20. Study of action of cyclophosphamide and extract of mycelium of Pleurotus ostreatus in vivo on mice, bearing melanoma B16-F0-GFP

    NASA Astrophysics Data System (ADS)

    Meerovich, Irina G.; Yang, Meng; Jiang, Ping; Hoffman, Robert M.; Gerasimenya, Valery P.; Orlov, Alexander E.; Savitsky, Alexander P.; Popov, Vladimir O.

    2005-04-01

    In this work we studied in vivo the combined action of cyclophosphamide and the extract of mycelium of Pleurotus ostreatus on mice bearing melanoma B16-F0, expressing green fluorescent protein (GFP). This model allows to recognize small-size tumors and metastases, unrecognizable by other methods. It was found that combined administration of cyclophosphamide (300 mg/kg) and the extract of mycelium of Pleurotus ostreatus (100 mg/kg), administered for 10 days after cyclophosphamide injection, as well administration of cyclophosphamide alone, cause inhibition of tumor growth about 97%. It was shown that administration of the extract of mycelium of Pleurotus ostreatus alone leads to inhibition of tumor growth of 61%. It was found that in case of combined administration of cyclophosphamide and the extract of mycelium of Pleurotus ostreatus, leucopenia was less expressed than in case of administration of cyclophosphamide alone.

  1. Role of the local structure in superconductivity of LaO0.5F0.5BiS2-x Se x system.

    PubMed

    Paris, E; Mizuguchi, Y; Hacisalihoglu, M Y; Hiroi, T; Joseph, B; Aquilanti, G; Miura, O; Mizokawa, T; Saini, N L

    2017-04-12

    We have studied the local structure of LaO0.5F0.5BiS2-x Se x by Bi L1-edge extended x-ray absorption fine structure (EXAFS). We find a significant effect of Se substitution on the local atomic correlations with a gradual elongation of average in-plane Bi-S bondlength. The associated mean square relative displacement, measuring average local distortions in the BiS2 plane, hardly shows any change for small Se substitution, but decreases significantly for [Formula: see text]. The Se substitution appears to suppress the local distortions within the BiS2 plane that may optimize in-plane orbital hybridization and hence the superconductivity. The results suggest that the local structure of the BiS2-layer is one of the key ingredients to control the physical properties of the BiS2-based dichalcogenides.

  2. Role of the local structure in superconductivity of LaO0.5F0.5BiS2-x Se x system

    NASA Astrophysics Data System (ADS)

    Paris, E.; Mizuguchi, Y.; Hacisalihoglu, M. Y.; Hiroi, T.; Joseph, B.; Aquilanti, G.; Miura, O.; Mizokawa, T.; Saini, N. L.

    2017-04-01

    We have studied the local structure of LaO0.5F0.5BiS2-x Se x by Bi L1-edge extended x-ray absorption fine structure (EXAFS). We find a significant effect of Se substitution on the local atomic correlations with a gradual elongation of average in-plane Bi-S bondlength. The associated mean square relative displacement, measuring average local distortions in the BiS2 plane, hardly shows any change for small Se substitution, but decreases significantly for x≥slant 0.6 . The Se substitution appears to suppress the local distortions within the BiS2 plane that may optimize in-plane orbital hybridization and hence the superconductivity. The results suggest that the local structure of the BiS2-layer is one of the key ingredients to control the physical properties of the BiS2-based dichalcogenides.

  3. Optical Study of LaO0.9F0.1FeAs: Evidence for a Weakly Coupled Superconducting State

    NASA Astrophysics Data System (ADS)

    Drechsler, S.-L.; Grobosch, M.; Koepernik, K.; Behr, G.; Köhler, A.; Werner, J.; Kondrat, A.; Leps, N.; Hess, C.; Klingeler, R.; Schuster, R.; Büchner, B.; Knupfer, M.

    2008-12-01

    We have studied the reflectance of the recently discovered superconductor LaO0.9F0.1FeAs in a wide energy range from the far infrared to the visible regime. We report on the observation of infrared active phonons, the plasma edge, and possible interband transitions. On the basis of this data and the reported in-plane penetration depth λL(0)=254nm [H. Luetkens , Phys. Rev. Lett. 101, 097009 (2008)PRLTAO0031-900710.1103/PhysRevLett.101.097009] a disorder sensitive relatively small value of the total electron-boson coupling constant λtot=λe-ph+λe-sp˜0.6±0.35 can be estimated adopting an effective single-band picture.

  4. Orientation-selective incorporation of transmembrane F0F1 ATP synthase complex from micrococcus luteus in polymer-supported membranes.

    PubMed

    Tutus, Murat; Rossetti, Fernanda F; Schneck, Emanuel; Fragneto, Giovanna; Förster, Friedrich; Richter, Ralf; Nawroth, Thomas; Tanaka, Motomu

    2008-11-10

    We report the vectorial incorporation of a highly asymmetric F0F1 ATP synthase complex from Micrococcus luteus into polymer-supported membranes. Dynamic light scattering and cryo electron microscopy confirm that the use of weak surfactants (bile acid) allows for the non-disruptive protein incorporation into lipid vesicles. Spreading of vesicles with ATP synthase onto a cellulose support results in a homogeneous distribution of proteins, in contrast to a patchy image observed on bare glass slides. The orientation of ATP synthase can be identified using an antibody to the ATP binding site as well as from topographic profiles of the surface. The method to "align" transmembrane proteins in supported membranes would open a possibility to quantify protein functions in biomimetic model systems.

  5. Trajectory dependent energy loss in grazing collisions of keV He atoms from a LiF(0 0 1) surface

    NASA Astrophysics Data System (ADS)

    Lienemann, J.; Hülsewede, D.; Seifert, J.; Maass, K.; Busch, M.; Winter, H.

    2013-11-01

    Angular distributions for scattering of 12 keV He atoms from a LiF(0 0 1) surface under a grazing angle of incidence were recorded in coincidence with the projectile energy loss and the number of electrons emitted from the target surface during the collision. For scattering along the low indexed <1 1 0> and <1 0 0> directions of the crystal surface collisional rainbow peaks were observed. For scattering along a <1 1 0> direction the resulting rainbow peaks can be attributed to scattering from strings of anions which form active sites for charge exchange and emission of electrons. The data can be interpreted by trajectory computer simulations where charge transfer takes place from F- sites.

  6. Multiband superconductivity in LaFeAsO0.9F0.1 single crystals probed by high-field vortex torque magnetometry

    NASA Astrophysics Data System (ADS)

    Li, G.; Grissonnanche, G.; Gurevich, A.; Zhigadlo, N. D.; Katrych, S.; Bukowski, Z.; Karpinski, J.; Balicas, L.

    2011-06-01

    To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of the magnetic torque τ(θ) in the mixed state of LaO0.9F0.1FeAs single crystals as a function of temperature T and magnetic fields H up to 18 T. The paramagnetic contribution of the Fe ions is properly treated in order to extract the effective mass anisotropy parameter γ=(mc/mab)1/2 from τ(θ). We show that γ depends strongly on both T and H, reaching a maximum value of ~10 followed by a decrease toward values close to 1 as T is lowered. The observed field dependencies of the London penetration depth λab and γ suggest the onset of suppression of a superconducing gap at H≈Hc2/3.

  7. High magnetic field vortex torque magnetometry in SmFeAsO0.8F0.2 single crystals

    NASA Astrophysics Data System (ADS)

    Balicas, Luis; Gurevich, Alex; Jo, Younjung; Jaroszynski, Jan; Larbalestier, David; Liu, R. H.; Chen, H.; Chen, Xianhui H.; Zhigadlo, N. D.; Katrych, S.; Bukowski, Z.; Karpinski, J.

    2009-03-01

    To probe manifestations of multiband superconductivity in oxypnictides, we measured the angular dependence of magnetic torque τ(θ) in the mixed state of SmO0.8F0.2FeAs single crystals as functions of temperature T and high magnetic field H up to 30 T. We show that the effective mass anisotropy parameter γ extracted from τ(θ), can be greatly overestimated if the strong paramagnetism of Sm or Fe ions is not properly taken into account. The correctly extracted γ depends on both T and H, saturating at γ˜9 at lower temperatures. Neither the London penetration depth nor the superfluid density is affected by high fields fields up to the upper critical field. Our results indicate two strongly-coupled superconducting gaps of nearly equal magnitudes.

  8. Fluctuation conductivity and possible pseudogap state in FeAs-based superconductor EuFeAsO0.85F0.15

    NASA Astrophysics Data System (ADS)

    Solovjov, A. L.; Omelchenko, L. V.; Terekhov, A. V.; Rogacki, K.; Vovk, R. V.; Khlybov, E. P.; Chroneos, A.

    2016-07-01

    The study of excess conductivity σ \\prime (T) in the textured polycrystalline FeAs-based superconductor EuFeAsO0.85F0.15 ({T}{{c}}=11 {{K}}) prepared by the solid state synthesis is reported for the first time. The σ \\prime (T) analysis has been performed within the local pair (LP) model based on the assumption of the LPs formation in cuprate high-T c superconductors (cuprates) below the pseudogap (PG) temperature {T}* \\gg {T}{{c}}. Similarly to the cuprates, near {T}{{c}} σ \\prime (T) is adequately described by the 3D term of the Aslamasov-Larkin (AL) theory but the range of the 3D-AL fluctuations, {{Δ }}{T}3{{D}}, is relatively short. Above the crossover temperature {T}0≈ 11.7 {{K}} σ \\prime (T) is described by the 2D Maki-Thompson (MT) fluctuation term of the Hikami-Larkin theory. But enhanced 2D-MT fluctuation contribution being typical for the magnetic superconductors is observed. Within the LP model the PG parameter, {{{Δ }}}* (T), was determined for the first time. It is shown that {{{Δ }}}* (T) demonstrates the narrow maximum at {T}s≈ 160 {{K}} followed by the descending linear length down to {T}{SDW}={T}{NFe}≈ 133 {{K}}. Observed small {{Δ }}{T}3{{D}}, enlarged 2D σ \\prime (T) and linear {{{Δ }}}* (T) are considered to be the evidence of the enhanced magnetic interaction in EuFeAsO0.85F0.15. Importantly, the slop of the linear {{{Δ }}}* (T) and its length are found to be the same as it is revealed for SmFeAsO0.85. The results suggest both the similarity of the magnetic interaction processes in different Fe-pnictides and applicability of the LP model to the σ \\prime (T) analysis even in magnetic superconductors.

  9. Structural and functional investigations of biological catalysts for optimization of solar-driven H II production systems

    NASA Astrophysics Data System (ADS)

    King, Paul W.; Svedruzic, Drazenka; Cohen, Jordi; Schulten, Klaus; Seibert, Michael; Ghirardi, Maria L.

    2006-08-01

    Research efforts to develop efficient systems for H II production encompass a variety of biological and chemical approaches. For solar-driven H II production we are investigating an approach that integrates biological catalysts, the [FeFe] hydrogenases, with a photoelectrochemical cell as a novel bio-hybrid system. Structurally the [FeFe] hydrogenases consist of an iron-sulfur catalytic site that in some instances is electronically wired to accessory iron-sulfur clusters proposed to function in electron transfer. The inherent structural complexity of most examples of these enzymes is compensated by characteristics desired for bio-hybrid systems (i.e., low activation energy, high catalytic activity and solubility) with the benefit of utilizing abundant, less costly non-precious metals. Redesign and modification of [FeFe] hydrogenases is being undertaken to reduce complexity and to optimize structural properties for various integration strategies. The least complex examples of [FeFe] hydrogenase are found in the species of photosynthetic green algae and are being studied as design models for investigating the effects of structural minimization on substrate transfer, catalytic activity and oxygen sensitivity. Redesigning hydrogenases for effective use in bio-hybrid systems requires a detailed understanding of the relationship between structure and catalysis. To achieve better mechanistic understanding of [FeFe] hydrogenases both structural and dynamic models are being used to identify potential substrate transfer mechanisms which are tested in an experimental system. Here we report on recent progress of our investigations in the areas of [FeFe] hydrogenase overexpression, minimization and biochemical characterization.

  10. Macroscopic and microscopic investigation of Ni(II) sequestration on diatomite by batch, XPS, and EXAFS techniques.

    PubMed

    Sheng, Guodong; Yang, Shitong; Sheng, Jiang; Hu, Jun; Tan, Xiaoli; Wang, Xiangke

    2011-09-15

    Sequestration of Ni(II) on diatomite as a function of time, pH, and temperature was investigated by batch, XPS, and EXAFS techniques. The ionic strength-dependent sorption at pH < 7.0 was consistent with outer-sphere surface complexation, while the ionic strength-independent sorption at pH = 7.0-8.6 was indicative of inner-sphere surface complexation. EXAFS results indicated that the adsorbed Ni(II) consisted of ∼6 O at R(Ni-O) ≈ 2.05 Å. EXAFS analysis from the second shell suggested that three phenomena occurred at the diatomite/water interface: (1) outer-sphere and/or inner-sphere complexation; (2) dissolution of Si which is the rate limiting step during Ni uptake; and (3) extensive growth of surface (co)precipitates. Under acidic conditions, outer-sphere complexation is the main mechanism controlling Ni uptake, which is in good agreement with the macroscopic results. At contact time of 1 h or 1 day or pH = 7.0-8.0, surface coprecipitates occur concurrently with inner-sphere complexes on diatomite surface, whereas at contact time of 1 month or pH = 10.0, surface (co)precipitates dominate Ni uptake. Furthermore, surface loading increases with temperature increasing, and surface coprecipitates become the dominant mechanism at elevated temperature. The results are important to understand Ni interaction with minerals at the solid-water interface, which is helpful to evaluate the mobility of Ni(II) in the natural environment.

  11. Saturn's icy satellites investigated by Cassini-VIMS. II. Results at the end of nominal mission

    USGS Publications Warehouse

    Filacchione, G.; Capaccioni, F.; Clark, R.N.; Cuzzi, J.N.; Cruikshank, D.P.; Coradini, A.; Cerroni, P.; Nicholson, P.D.; McCord, T.B.; Brown, R.H.; Buratti, B.J.; Tosi, F.; Nelson, R.M.; Jaumann, R.; Stephan, K.

    2010-01-01

    We report the detailed analysis of the spectrophotometric properties of Saturn's icy satellites as derived by full-disk observations obtained by visual and infrared mapping spectrometer (VIMS) experiment aboard Cassini. In this paper, we have extended the coverage until the end of the Cassini's nominal mission (June 1st 2008), while a previous paper (Filacchione, G., and 28 colleagues [2007]. Icarus 186, 259-290, hereby referred to as Paper I) reported the preliminary results of this study. During the four years of nominal mission, VIMS has observed the entire population of Saturn's icy satellites allowing us to make a comparative analysis of the VIS-NIR spectral properties of the major satellites (Mimas, Enceladus, Tethys, Dione, Rhea, Hyperion, Iapetus) and irregular moons (Atlas, Prometheus, Pandora, Janus, Epimetheus, Telesto, Calypso, Phoebe). The results we discuss here are derived from the entire dataset available at June 2008 which consists of 1417 full-disk observations acquired from a variety of distances and inclinations from the equatorial plane, with different phase angles and hemispheric coverage. The most important spectrophotometric indicators (as defined in Paper I: I/F continua at 0.55 ??m, 1.822 ??m and 3.547 ??m, visible spectral slopes, water and carbon dioxide bands depths and positions) are calculated for each observation in order to investigate the disk-integrated composition of the satellites, the distribution of water ice respect to "contaminants" abundances and typical regolith grain properties. These quantities vary from the almost pure water ice surfaces of Enceladus and Calypso to the organic and carbon dioxide rich Hyperion, Iapetus and Phoebe. Janus visible colors are intermediate between these two classes having a slightly positive spectral slope. These results could help to decipher the origins and evolutionary history of the minor moons of the Saturn's system. We introduce a polar representation of the spectrophotometric

  12. Delta mu Na+ drives the synthesis of ATP via an delta mu Na(+)-translocating F1F0-ATP synthase in membrane vesicles of the archaeon Methanosarcina mazei Gö1.

    PubMed Central

    Becher, B; Müller, V

    1994-01-01

    Methanosarcina mazei Gö1 couples the methyl transfer from methyl-tetrahydromethanopterin to 2-mercaptoethanesulfonate (coenzyme M) with the generation of an electrochemical sodium ion gradient (delta mu Na+) and the reduction of the heterodisulfide of coenzyme M and 7-mercaptoheptanoylthreoninephosphate with the generation of an electrochemical proton gradient (delta muH+). Experiments with washed inverted vesicles were performed to investigate whether both ion gradients are used directly for the synthesis of ATP. delta mu Na+ and delta mu H+ were both able to drive the synthesis of ATP in the vesicular system. ATP synthesis driven by heterodisulfide reduction (delta mu H+) or an artificial delta pH was inhibited by the protonophore SF6847 but not by the sodium ionophore ETH157, whereas ETH157 but not SF6847 inhibited ATP synthesis driven by a chemical sodium ion gradient (delta pNa) as well as the methyl transfer reaction (delta mu Na+). Inhibition of the Na+/H+ antiporter led to a stimulation of ATP synthesis driven by the methyl transfer reaction (delta mu Na+), as well as by delta pNa. These experiments indicate that delta mu Na+ and delta mu H+ drive the synthesis of ATP via an Na(+)- and an H(+)-translocating ATP synthase, respectively. Inhibitor studies were performed to elucidate the nature of the ATP synthase(s) involved. delta pH-driven ATP synthesis was specifically inhibited by bafilomycin A1, whereas delta pNa-driven ATP synthesis was exclusively inhibited by 7-chloro-4-nitro-2-oxa-1,3-diazole, azide, and venturicidin. These results are evidence for the presence of an F(1)F(0)-ATP synthase in addition to the A(1)A(0)-ATP synthase in membranes of M. Mazei Gö1 and suggest that the F(1)F(0)-type enzyme is an Na+-translocating ATP synthase, whereas the A(1)A(0)-ATP synthase uses H+ as the coupling ion. PMID:8169202

  13. Investigation of Oxide Bifilms in Investment Cast Superalloy IN100: Part II. Characterization

    NASA Astrophysics Data System (ADS)

    Kaplan, Max A.; Fuchs, Gerhard E.

    2016-05-01

    Oxide bifilms are a proposed casting inclusion reported to have been observed in vacuum investment cast polycrystalline Ni-based superalloys. Ongoing research seeks to determine if current superalloy casting practices can result in the formation of oxide bifilms, and subsequently if it is possible to observe and characterize this phenomenon. The effect of casting atmosphere, turbulence, filtering, hot isostatic pressing, and heat treatment has been investigated to identify the critical parameters that have been reported to result in bifilm formation in Ni-based superalloy IN100. Scanning Auger microscopy (SAM), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HR-TEM) were utilized to characterize samples from each casting condition. In situ ultrahigh vacuum Auger fractography did not indicate the presence of bifilms on the fracture behavior of IN100 in any processing condition. SAM analysis identified a sulfur-enriched monolayer on the surface of dendritic casting porosity, and identified heterogeneous Ti oxycarbide inclusions in air cast IN100. SEM analysis also indicated the presence of Ti oxycarbide inclusions in air cast IN100, and determined that these inclusion structures consist of fine blocky external M(Ti, Mo)C carbide enveloping an internal core of alumina. HR-TEM analysis indicated that none of the oxycarbide inclusion interfaces exist as discontinuous unbound interfaces, and that the internal alumina core is an ultra-fine polycrystalline structure.

  14. High-resolution x-ray diffraction investigations of highly mismatched II-VI quantum wells

    NASA Astrophysics Data System (ADS)

    Passow, T.; Leonardi, K.; Stockmann, A.; Selke, H.; Heinke, H.; Hommel, D.

    1999-05-01

    High-resolution x-ray diffraction (HRXRD) was used to systematically investigate CdSe and ZnTe quantum wells one to three monolayers thick sandwiched between a ZnSe buffer and cap layer grown at different substrate temperatures. For comparison high-resolution transmission electron microscopy (HRTEM) measurements were performed which were evaluated by digital analysis of lattice images. The x-ray diffraction profiles show typically two main layer peaks. Their intensity ratio depends critically on the quantum well thickness and varies only weakly with the thickness of the ZnSe layers. The total Cd or Te content determined from comparisons of experimental and simulated (004) icons/Journals/Common/omega" ALT="omega" ALIGN="TOP"/>-2icons/Journals/Common/theta" ALT="theta" ALIGN="TOP"/> scans is well confirmed by the results from digital analysis of HRTEM lattice images. For quantum well thicknesses larger than 1.5 (ZnTe) or 2.0 (CdSe) monolayers, no simulation parameters could be found to achieve good agreement between theoretical and measured diffraction profiles. This transition is more clearly visible in diffraction profiles of asymmetrical reflections. By HRTEM measurements, this could be correlated to the occurrence of stacking faults at these thicknesses. The formation of quantum islands detected by HRTEM was not reflected in the HRXRD icons/Journals/Common/omega" ALT="omega" ALIGN="TOP"/>-2icons/Journals/Common/theta" ALT="theta" ALIGN="TOP"/> scans.

  15. Investigation of injury/illness data at a nuclear facility. Part II

    SciTech Connect

    Cournoyer, Michael E.; Garcia, Vincent E.; Sandoval, Arnold N.; George, Gerald L.; Gubernatis, David C.; Schreiber, Stephen B.

    2015-07-01

    At Los Alamos National Laboratory (LANL), there are several nuclear facilities, accelerator facilities, radiological facilities, explosives sites, moderate- and high-hazard non-nuclear facilities, biosciences laboratory, etc. The Plutonium Science and Manufacturing Directorate (ADPSM) provides special nuclear material research, process development, technology demonstration, and manufacturing capabilities. ADPSM manages the LANL Plutonium Facility. Within the Radiological Control Area at TA-55 (PF-4), chemical and metallurgical operations with plutonium and other hazardous materials are performed. LANL Health and Safety Programs investigate injury and illness data. In this study, statistically significant trends have been identified and compared for LANL, ADPSM, and PF-4 injury/illness cases. A previously described output metric is used to measures LANL management progress towards meeting its operational safety objectives and goals. Timelines are used to determine trends in Injury/Illness types. Pareto Charts are used to prioritize causal factors. The data generated from analysis of Injury/Illness data have helped identify and reduce the number of corresponding causal factors.

  16. Investigation of injury/illness data at a nuclear facility. Part II

    DOE PAGES

    Cournoyer, Michael E.; Garcia, Vincent E.; Sandoval, Arnold N.; ...

    2015-07-01

    At Los Alamos National Laboratory (LANL), there are several nuclear facilities, accelerator facilities, radiological facilities, explosives sites, moderate- and high-hazard non-nuclear facilities, biosciences laboratory, etc. The Plutonium Science and Manufacturing Directorate (ADPSM) provides special nuclear material research, process development, technology demonstration, and manufacturing capabilities. ADPSM manages the LANL Plutonium Facility. Within the Radiological Control Area at TA-55 (PF-4), chemical and metallurgical operations with plutonium and other hazardous materials are performed. LANL Health and Safety Programs investigate injury and illness data. In this study, statistically significant trends have been identified and compared for LANL, ADPSM, and PF-4 injury/illness cases. A previouslymore » described output metric is used to measures LANL management progress towards meeting its operational safety objectives and goals. Timelines are used to determine trends in Injury/Illness types. Pareto Charts are used to prioritize causal factors. The data generated from analysis of Injury/Illness data have helped identify and reduce the number of corresponding causal factors.« less

  17. Identification of Criticality in Neuronal Avalanches: II. A Theoretical and Empirical Investigation of the Driven Case

    PubMed Central

    2014-01-01

    The observation of apparent power laws in neuronal systems has led to the suggestion that the brain is at, or close to, a critical state and may be a self-organised critical system. Within the framework of self-organised criticality a separation of timescales is thought to be crucial for the observation of power-law dynamics and computational models are often constructed with this property. However, this is not necessarily a characteristic of physiological neural networks—external input does not only occur when the network is at rest/a steady state. In this paper we study a simple neuronal network model driven by a continuous external input (i.e. the model does not have an explicit separation of timescales from seeding the system only when in the quiescent state) and analytically tuned to operate in the region of a critical state (it reaches the critical regime exactly in the absence of input—the case studied in the companion paper to this article). The system displays avalanche dynamics in the form of cascades of neuronal firing separated by periods of silence. We observe partial scale-free behaviour in the distribution of avalanche size for low levels of external input. We analytically derive the distributions of waiting times and investigate their temporal behaviour in relation to different levels of external input, showing that the system’s dynamics can exhibit partial long-range temporal correlations. We further show that as the system approaches the critical state by two alternative ‘routes’, different markers of criticality (partial scale-free behaviour and long-range temporal correlations) are displayed. This suggests that signatures of criticality exhibited by a particular system in close proximity to a critical state are dependent on the region in parameter space at which the system (currently) resides. PMID:24872924

  18. Polarized XANES and EXAFS spectroscopic investigation into copper(II) complexes on vermiculite

    NASA Astrophysics Data System (ADS)

    Furnare, Luca J.; Vailionis, Arturas; Strawn, Daniel G.

    2005-11-01

    Interaction of heavy metals with clay minerals can dominate solid-solution reactions in soil, controlling the fate of the metals in the environment. In this study we used powdered and polarized extended X-ray absorption fine structure (EXAFS) spectroscopy and X-ray absorption near edge spectroscopy (XANES) to investigate Cu sorbed on Llano vermiculite and compare the results to reported Cu sorption mechanism on Wyoming (WY) smectite and reduced South African (SA) vermiculite. Analysis of the Cu K-edge spectra revealed that Cu sorbed on Llano vermiculite at high ionic strength ( I) has the greatest degree of covalent bond character, followed by Cu sorbed on montmorillonite at high I, and Cu sorbed on reduced SA vermiculite at high I. Cu sorbed on clay minerals at low I has the least covalent character. EXAFS data from Cu sorbed Ca- and K-equilibrated Llano vermiculites showed the presence of a second-shell Al, Si, or Mg backscatterer at 3.02 Å. This distance is consistent with Cu sorbing via a corner-sharing monodentate or bidentate bond. Polarized XANES and EXAFS results revealed that the angle between the Cu atom and the mineral sorption sites is 68° with respect to the [001] direction. From the bond angle and the persistence of the second-shell backscatterer when the interlayer is collapsed (K-equilibration), we conclude that Cu adsorption on the Llano vermiculite is not occurring in the interlayer but rather Cu is adsorbing onto the edges of the vermiculite. Results from this research provide evidence that Cu forms inner-sphere and outer-sphere complexes on clay minerals, and does not form the vast multinuclear surface precipitates that have been observed for Co, Zn, and Ni.

  19. Identification of Criticality in Neuronal Avalanches: II. A Theoretical and Empirical Investigation of the Driven Case.

    PubMed

    Hartley, Caroline; Taylor, Timothy J; Kiss, Istvan Z; Farmer, Simon F; Berthouze, Luc

    2014-01-01

    The observation of apparent power laws in neuronal systems has led to the suggestion that the brain is at, or close to, a critical state and may be a self-organised critical system. Within the framework of self-organised criticality a separation of timescales is thought to be crucial for the observation of power-law dynamics and computational models are often constructed with this property. However, this is not necessarily a characteristic of physiological neural networks-external input does not only occur when the network is at rest/a steady state. In this paper we study a simple neuronal network model driven by a continuous external input (i.e. the model does not have an explicit separation of timescales from seeding the system only when in the quiescent state) and analytically tuned to operate in the region of a critical state (it reaches the critical regime exactly in the absence of input-the case studied in the companion paper to this article). The system displays avalanche dynamics in the form of cascades of neuronal firing separated by periods of silence. We observe partial scale-free behaviour in the distribution of avalanche size for low levels of external input. We analytically derive the distributions of waiting times and investigate their temporal behaviour in relation to different levels of external input, showing that the system's dynamics can exhibit partial long-range temporal correlations. We further show that as the system approaches the critical state by two alternative 'routes', different markers of criticality (partial scale-free behaviour and long-range temporal correlations) are displayed. This suggests that signatures of criticality exhibited by a particular system in close proximity to a critical state are dependent on the region in parameter space at which the system (currently) resides.

  20. A phase II study of an investigational tetravalent influenza vaccine formulation combining MF59®

    PubMed Central

    Herbinger, Karl-Heinz; von Sonnenburg, Frank; Nothdurft, Hans Dieter; Perona, Pamela; Borkowski, Astrid; Fragapane, Elena; Nicolay, Uwe; Clemens, Ralf

    2014-01-01

    An investigational tetravalent vaccine combining pre-pandemic, MF59®-adjuvanted A/H5N1 vaccine with non-adjuvanted, trivalent, seasonal influenza vaccine has been developed, which has the potential to be used for pre-pandemic priming and to improve levels of compliance and coverage. It is important to determine whether the safety and immunogenicity of the combination vaccine is equivalent to that of the two separate vaccines when administered concomitantly. Healthy adults (n = 601) were randomly assigned to three vaccination groups to receive either: (1) tetravalent vaccine and placebo concomitantly (in separate arms) on Day 1, followed by A/H5N1 vaccine on Day 22; (2) A/H5N1 vaccine and placebo concomitantly on Day 1, followed by tetravalent vaccine on Day 22; or (3) A/H5N1 and seasonal vaccines concomitantly on Day 1, followed by A/H5N1 vaccine on Day 22. Antibody responses were measured using single radial hemolysis (SRH), haemagglutination inhibition (HI), and microneutralization (MN) assays on Days 1, 22, and 43. Solicited adverse reactions were recorded for seven days after vaccination. Spontaneous adverse events were recorded throughout the study. The tetravalent vaccine elicited antibody titers equivalent to those for separate A/H5N1 and seasonal vaccines, and sufficient to meet the European licensure criteria against A/H5N1 and all three seasonal strains. Local and systemic reactions were mainly mild to moderate. No vaccine-related serious adverse events occurred. These findings demonstrate that MF59-adjuvanted A/H5N1 and seasonal influenza vaccines had an acceptable safety profile and could be effectively administered as a tetravalent formulation, supporting the possibility of integrating pre-pandemic priming into seasonal influenza vaccination programs. PMID:24047817

  1. Status of volcanic hazard studies for the Nevada Nuclear Waste Storage Investigations. Volume II

    SciTech Connect

    Crowe, B.M.; Wohletz, K.H.; Vaniman, D.T.; Gladney, E.; Bower, N.

    1986-01-01

    Volcanic hazard investigations during FY 1984 focused on five topics: the emplacement mechanism of shallow basalt intrusions, geochemical trends through time for volcanic fields of the Death Valley-Pancake Range volcanic zone, the possibility of bimodal basalt-rhyolite volcanism, the age and process of enrichment for incompatible elements in young basalts of the Nevada Test Site (NTS) region, and the possibility of hydrovolcanic activity. The stress regime of Yucca Mountain may favor formation of shallow basalt intrusions. However, combined field and drill-hole studies suggest shallow basalt intrusions are rare in the geologic record of the southern Great Basin. The geochemical patterns of basaltic volcanism through time in the NTS region provide no evidence for evolution toward a large-volume volcanic field or increases in future rates of volcanism. Existing data are consistent with a declining volcanic system comparable to the late stages of the southern Death Valley volcanic field. The hazards of bimodal volcanism in this area are judged to be low. The source of a 6-Myr pumice discovered in alluvial deposits of Crater Flat has not been found. Geochemical studies show that the enrichment of trace elements in the younger rift basalts must be related to an enrichment of their mantle source rocks. This geochemical enrichment event, which may have been metasomatic alteration, predates the basalts of the silicic episode and is, therefore, not a young event. Studies of crater dimensions of hydrovolcanic landforms indicate that the worst case scenario (exhumation of a repository at Yucca Mountain by hydrovolcanic explosions) is unlikely. Theoretical models of melt-water vapor explosions, particularly the thermal detonation model, suggest hydrovolcanic explosion are possible at Yucca Mountain. 80 refs., 21 figs., 5 tabs.

  2. Investigation on aerodynamic characteristics of baseline-II E-2 blended wing-body aircraft with canard via computational simulation

    NASA Astrophysics Data System (ADS)

    Nasir, Rizal E. M.; Ali, Zurriati; Kuntjoro, Wahyu; Wisnoe, Wirachman

    2012-06-01

    Previous wind tunnel test has proven the improved aerodynamic charasteristics of Baseline-II E-2 Blended Wing-Body (BWB) aircraft studied in Universiti Teknologi Mara. The E-2 is a version of Baseline-II BWB with modified outer wing and larger canard, solely-designed to gain favourable longitudinal static stability during flight. This paper highlights some results from current investigation on the said aircraft via computational fluid dynamics simulation as a mean to validate the wind tunnel test results. The simulation is conducted based on standard one-equation turbulence, Spalart-Allmaras model with polyhedral mesh. The ambience of the flight simulation is made based on similar ambience of wind tunnel test. The simulation shows lift, drag and moment results to be near the values found in wind tunnel test but only within angles of attack where the lift change is linear. Beyond the linear region, clear differences between computational simulation and wind tunnel test results are observed. It is recommended that different type of mathematical model be used to simulate flight conditions beyond linear lift region.

  3. Experimental and theoretical investigation of a novel mononuclear copper(II) azido compound with tridentate (NNO) Schiff base

    NASA Astrophysics Data System (ADS)

    Karahan, Ahmet; Karabulut, Sedat; Dal, Hakan; Kurtaran, Raif; Leszczynski, Jerzy

    2015-08-01

    The tridentate (NNO) Schiff base (HL), has been prepared by the condensation of 2-(aminomethyl)pyridine with 5-chloro-salicylaldehyde. The mononuclear [N-(2-pyridylmethyl)-3-chloro-salicylaldiminato] (azido) copper(II) complex of general formula [Cu(L)(N3)] (1) has been synthesized by the treatment of HL and CuCl2·2H2O with sodium azide. The ligand and complex have been investigated by various methods including IR, TG-DTA and X-ray diffraction techniques. The complex crystallizes in monoclinic space group P21/c, with unit cell dimensions a = 6.7369(4), b = 11.6058(8), c = 17.1379(11) Å, β = 93.823(2)°. The distorted square-planar Cu(II) ion in complex is chelated by one imino N, one phenolic O and one pyridine N atoms of Schiff base ligand and one N atom of azide ion. The electrochemical behavior of the mononuclear copper azido complex was studied with cyclic voltammetry. Tautomer stability of the ligand and the complex has been determined by molecular modeling techniques. It has been concluded that the HL is more stable than its tautomeric form (THL) both as ligand and complex structures.

  4. Mechanistic Investigations of C-H Activations on Silica-Supported Co(ii) Sites in Catalytic Propane Dehydrogenation.

    PubMed

    Estes, Deven P

    2017-04-26

    Catalytic reactions involving C-H bond activations are central to the chemical industry. One such example, alkane dehydrogenation, has recently become very important due to shortfalls in propene production and a large supply of cheap propane. However, current technologies are inefficient and have only moderate selectivity. In order to understand how to improve currently used catalysts, we must know more about the mechanism by which propane is dehydrogenated. We show here that Co(ii) sites on silica are good catalysts for the dehydrogenation of propane, having high activity and selectivity that is reasonably stable over the course of 10 h. Mechanistic investigations of this catalyst show that the main activation mechanism is most likely C-H activation by 1,2 addition.

  5. Comparative analysis of 10 small molecules binding to carbonic anhydrase II by different investigators using Biacore technology.

    PubMed

    Papalia, Giuseppe A; Leavitt, Stephanie; Bynum, Maggie A; Katsamba, Phinikoula S; Wilton, Rosemarie; Qiu, Huawei; Steukers, Mieke; Wang, Siming; Bindu, Lakshman; Phogat, Sanjay; Giannetti, Anthony M; Ryan, Thomas E; Pudlak, Victoria A; Matusiewicz, Katarzyna; Michelson, Klaus M; Nowakowski, Agnes; Pham-Baginski, Anh; Brooks, Jonathan; Tieman, Bryan C; Bruce, Barry D; Vaughn, Michael; Baksh, Michael; Cho, Yun Hee; Wit, Mieke De; Smets, Alexandra; Vandersmissen, Johan; Michiels, Lieve; Myszka, David G

    2006-12-01

    In this benchmark study, 26 investigators were asked to characterize the kinetics and affinities of 10 sulfonamide inhibitors binding to the enzyme carbonic anhydrase II using Biacore optical biosensors. A majority of the participants collected data that could be fit to a 1:1 interaction model, but a subset of the data sets obtained from some instruments were of poor quality. The experimental errors in the k(a), k(d), and K(D) parameters determined for each of the compounds averaged 34, 24, and 37%, respectively. As expected, the greatest variation in the reported constants was observed for compounds with exceptionally weak affinity and/or fast association rates. The binding constants determined using the biosensor correlated well with solution-based titration calorimetry measurements. The results of this study provide insight into the challenges, as well as the level of experimental variation, that one would expect to observe when using Biacore technology for small molecule analyses.

  6. Structure and flexibility of the C-ring in the electromotor of rotary F(0)F(1)-ATPase of pea chloroplasts.

    PubMed

    Saroussi, Shai; Schushan, Maya; Ben-Tal, Nir; Junge, Wolfgang; Nelson, Nathan

    2012-01-01

    A ring of 8-15 identical c-subunits is essential for ion-translocation by the rotary electromotor of the ubiquitous F(O)F(1)-ATPase. Here we present the crystal structure at 3.4Å resolution of the c-ring from chloroplasts of a higher plant (Pisum sativum), determined using a native preparation. The crystal structure was found to resemble that of an (ancestral) cyanobacterium. Using elastic network modeling to investigate the ring's eigen-modes, we found five dominant modes of motion that fell into three classes. They revealed the following deformations of the ring: (I) ellipsoidal, (II) opposite twisting of the luminal circular surface of the ring against the stromal surface, and (III) kinking of the hairpin-shaped monomers in the middle, resulting in bending/stretching of the ring. Extension of the elastic network analysis to rings of different c(n)-symmetry revealed the same classes of dominant modes as in P. sativum (c(14)). We suggest the following functional roles for these classes: The first and third classes of modes affect the interaction of the c-ring with its counterparts in F(O), namely subunits a and bb'. These modes are likely to be involved in ion-translocation and torque generation. The second class of deformation, along with deformations of subunits γ and ε might serve to elastically buffer the torque transmission between F(O) and F(1).

  7. Targeted Mutagenesis in Atlantic Salmon (Salmo salar L.) Using the CRISPR/Cas9 System Induces Complete Knockout Individuals in the F0 Generation

    PubMed Central

    Edvardsen, Rolf B.; Leininger, Sven; Kleppe, Lene; Skaftnesmo, Kai Ove; Wargelius, Anna

    2014-01-01

    Understanding the biological function behind key proteins is of great concern in Atlantic salmon, both due to a high commercial importance and an interesting life history. Until recently, functional studies in salmonids appeared to be difficult. However, the recent discovery of targeted mutagenesis using the CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated) system enables performing functional studies in Atlantic salmon to a great extent. We used the CRISPR/Cas9 system to target two genes involved in pigmentation, tyrosinase (tyr) and solute carrier family 45, member 2 (slc45a2). Embryos were assayed for mutation rates at the 17 somite stage, where 40 and 22% of all injected embryos showed a high degree of mutation induction for slc45a2 and tyr, respectively. At hatching this mutation frequency was also visible for both targeted genes, displaying a graded phenotype ranging from complete lack of pigmentation to partial loss and normal pigmentation. CRISPRslc45a2/Cas9 injected embryos showing a complete lack of pigmentation or just a few spots of pigments also lacked wild type sequences when assaying more than 80 (slc45a2) sequence clones from whole embryos. This indicates that CRISPR/Cas9 can induce double-allelic knockout in the F0 generation. However, types and frequency of indels might affect the phenotype. Therefore, the variation of indels was assayed in the graded pigmentation phenotypes produced by CRISPR/Cas9-slc45a2. The results show a tendency for fewer types of indels formed in juveniles completely lacking pigmentation compared to juveniles displaying partial pigmentation. Another interesting observation was a high degree of the same indel type in different juveniles. This study shows for the first time successful use of the CRISPR/Cas9 technology in a marine cold water species. Targeted double-allelic mutations were obtained and, though the level of mosaicism has to be considered, we demonstrate that F0 fish can be used

  8. Targeted mutagenesis in Atlantic salmon (Salmo salar L.) using the CRISPR/Cas9 system induces complete knockout individuals in the F0 generation.

    PubMed

    Edvardsen, Rolf B; Leininger, Sven; Kleppe, Lene; Skaftnesmo, Kai Ove; Wargelius, Anna

    2014-01-01

    Understanding the biological function behind key proteins is of great concern in Atlantic salmon, both due to a high commercial importance and an interesting life history. Until recently, functional studies in salmonids appeared to be difficult. However, the recent discovery of targeted mutagenesis using the CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated) system enables performing functional studies in Atlantic salmon to a great extent. We used the CRISPR/Cas9 system to target two genes involved in pigmentation, tyrosinase (tyr) and solute carrier family 45, member 2 (slc45a2). Embryos were assayed for mutation rates at the 17 somite stage, where 40 and 22% of all injected embryos showed a high degree of mutation induction for slc45a2 and tyr, respectively. At hatching this mutation frequency was also visible for both targeted genes, displaying a graded phenotype ranging from complete lack of pigmentation to partial loss and normal pigmentation. CRISPRslc45a2/Cas9 injected embryos showing a complete lack of pigmentation or just a few spots of pigments also lacked wild type sequences when assaying more than 80 (slc45a2) sequence clones from whole embryos. This indicates that CRISPR/Cas9 can induce double-allelic knockout in the F0 generation. However, types and frequency of indels might affect the phenotype. Therefore, the variation of indels was assayed in the graded pigmentation phenotypes produced by CRISPR/Cas9-slc45a2. The results show a tendency for fewer types of indels formed in juveniles completely lacking pigmentation compared to juveniles displaying partial pigmentation. Another interesting observation was a high degree of the same indel type in different juveniles. This study shows for the first time successful use of the CRISPR/Cas9 technology in a marine cold water species. Targeted double-allelic mutations were obtained and, though the level of mosaicism has to be considered, we demonstrate that F0 fish can be used

  9. Ruthenium(II) and osmium(II) 1,2,3-triazolylidene organometallics: a preliminary investigation into the biological activity of 'click' carbene complexes.

    PubMed

    Kilpin, Kelly J; Crot, Stéphanie; Riedel, Tina; Kitchen, Jonathan A; Dyson, Paul J

    2014-01-21

    Taking advantage of the facile and versatile synthetic properties of 'click' 1,2,3-triazolylidene N-heterocyclic carbenes (tzNHC's), a range of new organometallic Ru(II) and Os(II) arene complexes containing functionalised tzNHC ligands, [M(η(6)-p-cymene)(tzNHC)Cl2] [M = Ru(II), Os(II)], have been synthesised and fully characterised, including the X-ray crystal structure of one of the Os(II) complexes. The tzNHC ligands remain coordinated to the metal centres under relevant physiological conditions, and following binding to the model protein, ubiquitin. The in vitro cytotoxicity of the compounds towards human ovarian cancer cells is dependent on the substituent on the tzNHC ligand but is generally <50 μM and in some cases <1 μM, whilst still retaining a high degree of selectivity towards cancer cells over healthy cells (1.85 μM in A2780 ovarian cancer cells versus 435 μM in human embryonic kidney cells in one case).

  10. Peripherally and non-peripherally tetra-benzothiazole substituted metal-free zinc (II) and lead (II) phthalocyanines: Synthesis, characterization, and investigation of photophysical and photochemical properties

    NASA Astrophysics Data System (ADS)

    Demirbaş, Ümit; Göl, Cem; Barut, Burak; Bayrak, Rıza; Durmuş, Mahmut; Kantekin, Halit; Değirmencioğlu, İsmail

    2017-02-01

    In this study, novel phthalonitrile compounds bearing 2-methylbenzo[d]thiazol-5-yloxy groups (4 and 5) and their peripherally and non-peripherally tetra-substituted metal-free (6 and 7), zinc (II) (8 and 9), and lead (II) (10 and 11) phthalocyanine derivatives were synthesized and characterized for the first time. These novel compounds showed extremely good solubility in most common organic solvents. The novel phthalocyanine compounds presented excellent results from photophysical and photochemical examinations in DMF solution. Especially, the singlet oxygen quantum yield (ΦΔ) values of the substituted zinc (II) phthalocyanines indicate that these compounds have significant potential as photosensitizers in cancer treatment by the photodynamic therapy (PDT) technique. The fluorescence quenching behaviour of these novel phthalocyanine compounds by 1,4-benzoquinone (BQ) was also examined in DMF solution.

  11. Complexation of heteroaromatic N-oxides with rhodium(II) tetracarboxylates in solution: DFT and NMR investigations

    NASA Astrophysics Data System (ADS)

    Głaszczka, Rafał; Jaźwiński, Jarosław

    2014-03-01

    Complexation of rhodium(II) tetraacetate and rhodium(II) tetrakistrifluoroacetate with a set of heteroaromatic N-oxides containing additional functional groups was investigated by means of density functional theory (DFT) calculations, and 1H, 13C and 15N nuclear magnetic resonance (NMR) spectroscopy in CDCl3 solutions. Chemical shifts for five N-oxides and their 1:1 adducts with rhodium tetraacetate were computed at the B3PW91/[6-311++G(2d,p), Stuttgart ECP)//B3LYP/[6-31G(2d), LANL2DZ] theory level applying IEF PCM (CHCl3) solvation model and taking into account various complexation modes and conformational variety. Calculated values were used for the estimation of complexation shifts Δδ (Δδ = δadduct - δligand). The largest negative complexation shift were estimated for heteroatoms bonded to Rh, from -37 to -70 ppm (N), from -100 to -160 ppm (O in NO group), from -13 to -23 ppm (O in OCH3 group), and from -12 to -22 ppm (Cl). For the remaining heteroatoms in adducts, the corresponding Δδ values ranged from -22 to +8.2 ppm (N), from +3 to +58 ppm (O) and from +6 to +51 ppm (Cl). The Δδ(1H) usually did not exceed 1 ppm, whereas Δδ(13C) varied from ca. -1 to +7 ppm. Some trends useful for the determination of the complexation site were extracted from calculated data sets. Theoretical findings were applied to analyse experimental NMR data.

  12. Phosphorylation of a peptide related to subunit c of the F0F1-ATPase/ATP synthase and relationship to permeability transition pore opening in mitochondria.

    PubMed

    Azarashvili, Tamara S; Tyynelä, Jaana; Odinokova, Irina V; Grigorjev, Pavel A; Baumann, Marc; Evtodienko, Yuri V; Saris, Nils-Erik L

    2002-08-01

    A phosphorylated polypeptide (ScIRP) from the inner membrane of rat liver mitochondria with an apparent molecular mass of 3.5 kDa was found to be immunoreactive with specific antibodies against subunit c of F0F1-ATPase/ATP synthase (Azarashvily, T. S., Tyynelä, J., Baumann, M., Evtodienko, Yu. V., and Saris, N.-E. L. (2000). Biochem. Biophys. Res. Commun. 270, 741-744. In the present paper we show that the dephosphorylation of ScIRP was promoted by the Ca2+-induced mitochondrial permeability transition (MPT) and prevented by cyclosporin A. Preincubation of ScIRP isolated in its dephosphorylated form with the mitochondrial suspension decreased the membrane potential (delta psiM) and the Ca2+-uptake capacity by promoting MPT. Incorporation of ScIRP into black-lipid membranes increased the membrane conductivity by inducing channel formation that was also suppressed by antibodies to subunit c. These data indicate that the phosphorylation level of ScIRP is influenced by the MPT pore state, presumably by stimulation of calcineurin phosphatase by the Ca2+ used to induce MPT. The possibility of ScIRP being part of the MPT pore assembly is discussed in view of its capability to induced channel activity.

  13. Production and characterization of a novel monoclonal antibody against Vibrio parahaemolyticus F0F1 ATP synthase's delta subunit and its application for rapid identification of the pathogen.

    PubMed

    Sakata, Junko; Kawatsu, Kentaro; Iwasaki, Tadashi; Tanaka, Katsuhiro; Takenaka, Shigeo; Kumeda, Yuko; Kodama, Hiroshi

    2012-01-01

    We raised monoclonal antibodies (MAbs) against Vibrio parahaemolyticus cell extracts. One of the MAbs, designated MAb-VP34, reacted in enzyme-linked immunosorbent assays (ELISAs) with 140 V. parahaemolyticus strains, regardless of serotype or origin. MAb-VP34 did not detectably react with 96 strains belonging to 27 other Vibrio species (except for Vibrio natriegens) or with 29 non-Vibrio species. These results show that MAb-VP34 is highly specific for V. parahaemolyticus. Western blotting and mass spectrometry analyses revealed that MAb-VP34 recognized V. parahaemolyticus F(0)F(1) ATP synthase's delta subunit. Using MAb-VP34, a rapid and simple immunodot blotting assay (VP-Dot) was developed to determine whether bacterial colonies growing on selective agar, represented V. parahaemolyticus. To evaluate VP-Dot, 20 V. parahaemolyticus strains and 19 non-related strains were tested. The results indicated that VP-Dot is a reliable tool for identification of V. parahaemolyticus colonies. The simple VP-Dot procedure took 40min, indicating that the MAb-VP34 based immunological method will greatly reduce labor, time, and costs required to verify V. parahaemolyticus colonies as compared with the conventional biochemical test.

  14. Biallelic mutations in the gene encoding eEF1A2 cause seizures and sudden death in F0 mice

    PubMed Central

    Davies, Faith C. J.; Hope, Jilly E.; McLachlan, Fiona; Nunez, Francis; Doig, Jennifer; Bengani, Hemant; Smith, Colin; Abbott, Catherine M.

    2017-01-01

    De novo heterozygous missense mutations in the gene encoding translation elongation factor eEF1A2 have recently been found to give rise to neurodevelopmental disorders. Children with mutations in this gene have developmental delay, epilepsy, intellectual disability and often autism; the most frequently occurring mutation is G70S. It has been known for many years that complete loss of eEF1A2 in mice causes motor neuron degeneration and early death; on the other hand heterozygous null mice are apparently normal. We have used CRISPR/Cas9 gene editing in the mouse to mutate the gene encoding eEF1A2, obtaining a high frequency of biallelic mutations. Whilst many of the resulting founder (F0) mice developed motor neuron degeneration, others displayed phenotypes consistent with a severe neurodevelopmental disorder, including sudden unexplained deaths and audiogenic seizures. The presence of G70S protein was not sufficient to protect mice from neurodegeneration in G70S/− mice, showing that the mutant protein is essentially non-functional. PMID:28378778

  15. From controversy to precision on the sigma meson: A review on the status of the non-ordinary f0(500) resonance

    NASA Astrophysics Data System (ADS)

    Peláez, José R.

    2016-11-01

    The existence and properties of the sigma meson have been controversial for almost six decades, despite playing a central role in the spontaneous chiral symmetry of QCD or in the nucleon-nucleon attraction. This controversy has also been fed by the strong indications that it is not an ordinary quark-antiquark meson. Here we review both the recent and old experimental data and the model independent dispersive formalisms which have provided precise determinations of its mass and width, finally settling the controversy and leading to its new name: f0(500) . We then provide a rather conservative average of the most recent and advanced dispersive determinations of its pole position √{sσ } = 449-16+22 - i(275 ± 12) . In addition, after comprehensive introductions, we will review within the modern perspective of effective theories and dispersion theory, its relation to chiral symmetry, unitarization techniques, its quark mass dependence, popular models, as well as the recent strong evidence, obtained from the QCD 1 /Nc expansion or Regge theory, for its non ordinary nature in terms of quarks and gluons.

  16. A Variable Temperature Synchrotron X-ray Diffraction Study of Colossal Magnetoresistant NdMnAsO0.95F0.05

    PubMed Central

    Wildman, E. J.; Mclaughlin, A. C.

    2016-01-01

    The recent discovery of high temperature superconductivity in Fe arsenides has invigorated research into transition metal pnictides. Colossal magnetoresistance (CMR) has recently been reported for NdMnAsO1-xFx for x = 0.05–0.08, with a maximum magnetoresistance achieved at low temperature (MR9T(3 K)) = −95%). This appears to be a novel mechanism of CMR, which is as a result of a second order phase transition in field from an insulating antiferromagnet to a semiconducting paramagnet. Here we report a variable temperature synchrotron X-ray powder diffraction study of the CMR oxypnictide NdMnAsO0.95F0.05 between 4 K–290 K. An excellent fit to the tetragonal unit cell with space group P4/nmm is obtained over the entire temperature range, with no change in crystal structure detected down to 4 K. A coupling of the lattice and magnetic order is observed, where subtle discontinuities in the temperature variation of a and the c/a ratio are apparent as the Nd spins order antiferromagnetically and the Mn moments reorient into the basal plane at TSR. The results suggest that very small changes in lattice parameters effect the coupling between lattice, electronic and magnetic degrees of freedom. PMID:26875693

  17. Information From the Voice Fundamental Frequency (F0) Region Accounts for the Majority of the Benefit When Acoustic Stimulation Is Added to Electric Stimulation

    PubMed Central

    Zhang, Ting; Dorman, Michael F.; Spahr, Anthony J.

    2013-01-01

    Objectives The aim of this study was to determine the minimum amount of low-frequency acoustic information that is required to achieve speech perception benefit in listeners with a cochlear implant in one ear and low-frequency hearing in the other ear. Design The recognition of monosyllabic words in quiet and sentences in noise was evaluated in three listening conditions: electric stimulation alone, acoustic stimulation alone, and combined electric and acoustic stimulation. The acoustic stimuli presented to the nonimplanted ear were either low-pass-filtered at 125, 250, 500, or 750 Hz, or unfiltered (wideband). Results Adding low-frequency acoustic information to electrically stimulated information led to a significant improvement in word recognition in quiet and sentence recognition in noise. Improvement was observed in the electric and acoustic stimulation condition even when the acoustic information was limited to the 125-Hz-low-passed signal. Further improvement for the sentences in noise was observed when the acoustic signal was increased to wideband. Conclusions Information from the voice fundamental frequency (F0) region accounts for the majority of the speech perception benefit when acoustic stimulation is added to electric stimulation. We propose that, in quiet, low-frequency acoustic information leads to an improved representation of voicing, which in turn leads to a reduction in word candidates in the lexicon. In noise, the robust representation of voicing allows access to low-frequency acoustic landmarks that mark syllable structure and word boundaries. These landmarks can bootstrap word and sentence recognition. PMID:20050394

  18. Extended chiral Khuri-Treiman formalism for η → 3π and the role of the a_0(980), f_0(980) resonances

    NASA Astrophysics Data System (ADS)

    Albaladejo, M.; Moussallam, B.

    2017-08-01

    Recent experiments on η → 3π decays have provided an extremely precise knowledge of the amplitudes across the Dalitz region which represent stringent constraints on theoretical descriptions. We reconsider an approach in which the low-energy chiral expansion is assumed to be optimally convergent in an unphysical region surrounding the Adler zero, and the amplitude in the physical region is uniquely deduced by an analyticity-based extrapolation using the Khuri-Treiman dispersive formalism. We present an extension of the usual formalism which implements the leading inelastic effects from the K\\bar{K} channel in the final-state π π interaction as well as in the initial-state η π interaction. The constructed amplitude has an enlarged region of validity and accounts in a realistic way for the influence of the two light scalar resonances f_0(980) and a_0(980) in the dispersive integrals. It is shown that the effect of these resonances in the low-energy region of the η → 3π decay is not negligible, in particular for the 3π ^0 mode, and improves the description of the energy variation across the Dalitz plot. Some remarks are made on the scale dependence and the value of the double quark mass ratio Q.

  19. The evacuation of British children during World War II: a preliminary investigation into the long-term psychological effects.

    PubMed

    Foster, D; Davies, S; Steele, H

    2003-09-01

    The authors used attachment theory to hypothesize about the possible long-term psychological effects of evacuation during World War II, focusing on children who were evacuated unaccompanied by their parents. The study aimed to establish whether this experience had long-term effects on psychological well-being, and to investigate mediating and moderating factors. The study utilized a retrospective non-randomized design, comparing 169 former evacuees with 43 people who were children during the war but not evacuated. No differences between the groups were found in terms of demographic variables or exposure to war-related events. All participants completed a range of standardized self-report questionnaires. Findings indicated that former evacuees were more likely to have insecure attachment styles and lower levels of present psychological well-being. Satisfaction with, but not quantity of, current social support was found to mediate the relationship between attachment style and present psychological well-being. Conclusions are limited due to the method of measurement of attachment style, non-randomized design and method of recruitment. Nevertheless, findings offer an indication that the experience of evacuation is associated with long-term psychological vulnerability through its relationship with insecure attachment.

  20. Investigation of the inhibitory properties of some phenolic standards and bee products against human carbonic anhydrase I and II.

    PubMed

    Aygul, Imdat; Yaylaci Karahalil, Fatma; Supuran, Claudiu T

    2016-01-01

    Polyphenols are important secondary products of plants with the potential to inhibit carbonic anhydrases. The aim of this study was to investigate the inhibition effects of various phenolic standards, honey, propolis, and pollen species on human carbonic anhydrase I and II. The inhibition values (IC50) of the phenolics (gallic acid, protocatechuic acid, quercetin, catechin, tannic acid, and chrysin) ranged from 0.009 to 0.32 μg/mL, tannic acid emerging as the best inhibitor. The inhibition values of three different types of honey, heather, rhododendron, and chestnut ranged between 2.32 and 25.10 μg/mL, the chestnut honeys exhibiting the best inhibition. The ethanolic extracts of pollen and propolis exhibited good inhibitory properties, with IC50 values between 0.486 and 3.320 μg/mL. In order to evaluate the phenolic composition of bee products, phenolic profiles and total phenolic contents (TFC) were also measured. The inhibition ranking among the natural products studied was phenolic standards > propolis > pollen > honeys, and inhibition was related to TFC.

  1. A systematic investigation on biological activities of a novel double zwitterionic Schiff base Cu(II) complex

    NASA Astrophysics Data System (ADS)

    Thalamuthu, S.; Annaraj, B.; Neelakantan, M. A.

    2014-01-01

    Double zwitterionic amino acid Schiff base, o-vanillylidene-L-histidine (OVHIS) and its copper complex (CuOVHIS) have been synthesized and characterized. CuOVHIS has distorted octahedral geometry, and OVHIS coordinates the copper ion in a tetradentate manner (N2O2). The pKa of OVHIS in aqueous solution was studied by potentiometric and spectrophotometric methods. DNA binding behavior of the compounds was investigated using spectrophotometric, cyclic voltammetric, and viscosity methods. The efficacy of DNA cleaving nature was tested on pUC19 DNA. The in vitro biological activity was tested against various micro organisms. The effect of CuOVHIS on the surface feature of Escherichia coli was analyzed by SEM. DPPH assay studies revealed that CuOVHIS has higher antioxidant activity. OVHIS inhibits proliferation of HCT117 cells with half maximal inhibition (IC50) of 71.15 ± 0.67. Chelation of OVHIS with Cu(II) ion enhances the inhibition of proliferation action (IC50 = 53.14 ± 0.67).

  2. Polarographic investigation of Cu(II) complexes with N,N,N',N'-tetrakis-(2-hydroxypropyl)-ethylenediamine.

    PubMed

    Norkus, E; Vaskelis, A; Zakaité, I; Reklaitis, J

    1995-11-01

    During investigation of the formation of Cu(2+) ion complexes with N,N,N',N'-tetrakis-(2-hydroxypropyl)-ethylenediamine (Quadrol-Q) by means of constant current polarography (20 degrees C, ionic strength J = 3 mol l(-1)), the possibility of the formation of two complex compounds; CuQ(2+) and CuQ(2+)(2), was shown within the pH range from 6 to 8. The logarithms of the stability constants for these compounds are 10.6 +/- 0.5 and 14.6 +/- 0.4 respectively. Cu(II) complexation increases sharply when the pH increases from 8 to 10. It was shown that the data at a pH of greater than 10 are in accordance with the existence of the hydroxy complexes CuQ(OH)(2) and CuQ(2)(OH)(2), the logarithms of the stability constants being 26.9 +/- 0.5 and 29.1 +/- 0.3.

  3. A Preliminary Investigation of the Utility of the "Behavior Support Plan Quality Evaluation Guide II" for Use in Australia

    ERIC Educational Resources Information Center

    Webber, Lynne S.; McVilly, Keith R.; Fester, Tarryn; Zazelis, Telly

    2011-01-01

    Background: The quality of behaviour support plans (BSPs) can be an important influence on the quality of the support provided to people with disability who show challenging behaviours. The Behavior Support Plan Quality Evaluation Guide II (BSP-QE II) is one tool that may be useful in assessing the quality of behaviour support plans. It has…

  4. A combined experimental and theoretical investigation of a new imineoxime and its palladium(II) and platinum(II) complexes: Synthesis, structural characterization and spectroscopic properties

    NASA Astrophysics Data System (ADS)

    Kaya, Yunus; Icsel, Ceyda; Yilmaz, Veysel T.; Buyukgungor, Orhan

    2014-12-01

    A new imineoxime compound {(1E,2E)-(2-hydroxy-ethylimino)-naphthalene-2yl-ethanal oxime (heineoH)} and its palladium(II) and platinum(II) complexes ([M(heineo)2]) have been synthesized and characterized by IR, NMR, UV-vis, elemental analysis, mass spectra and X-ray single crystal diffraction. [Pt(heineo)2] was obtained as a single crystal, while [Pd(heineo)2] was synthesized as a polycrystalline powder. The X-ray diffraction analysis of the [Pt(heineo)2] indicated that the platinum(II) ion is coordinated by two heineo ligands in a distorted square-planar geometry. DFT (B3LYP/6-311++G(d,p) and LANL2DZ) calculations on the ligand and its complexes were carried out to correlate the geometry and vibrational and electronic properties. Additionally, heineoH is fluorescent in EtOH at room temperature, but the fluorescence is quenched in the case of the metal complexes.

  5. A combined experimental and theoretical investigation of a new imineoxime and its palladium(II) and platinum(II) complexes: synthesis, structural characterization and spectroscopic properties.

    PubMed

    Kaya, Yunus; Icsel, Ceyda; Yilmaz, Veysel T; Buyukgungor, Orhan

    2014-12-10

    A new imineoxime compound {(1E,2E)-(2-hydroxy-ethylimino)-naphthalene-2yl-ethanal oxime (heineoH)} and its palladium(II) and platinum(II) complexes ([M(heineo)2]) have been synthesized and characterized by IR, NMR, UV-vis, elemental analysis, mass spectra and X-ray single crystal diffraction. [Pt(heineo)2] was obtained as a single crystal, while [Pd(heineo)2] was synthesized as a polycrystalline powder. The X-ray diffraction analysis of the [Pt(heineo)2] indicated that the platinum(II) ion is coordinated by two heineo ligands in a distorted square-planar geometry. DFT (B3LYP/6-311++G(d,p) and LANL2DZ) calculations on the ligand and its complexes were carried out to correlate the geometry and vibrational and electronic properties. Additionally, heineoH is fluorescent in EtOH at room temperature, but the fluorescence is quenched in the case of the metal complexes.

  6. A Primary Investigation on Serum CTX-II Changes in Patients Infected with Brucellosis in Qinghai Plateau, China.

    PubMed

    Zhao, Zhi Jun; Li, Qiang; Zhou, Xin; Ma, Li; Xu, Li Qing; Yang, Pei Zhen; Meng, Xian Ya; Yu, Hui Zhen; Xu, Xiao Qing; Cao, Jian Ying

    2016-03-01

    Brucellosis is one of the most widespread zoonotic diseases, with the most frequent complication being osteoarticular changes. The aim of this study was to assess the changes of C-terminal telopeptide of type II collagen (CTX-II) in patients infected with brucellosis. A total of 84 brucellosis patients and 43 volunteers were selected and divided into brucellosis vs. control groups. Serum samples were subjected to serological tests for brucellosis, and CTX-II levels in all samples were measured simultaneously with ELISA. The results showed that serum CTX-II levels in human brucellosis were higher than those of healthy controls, without a statistically significant difference, but serum CTX-II levels in male patients were significantly higher than those of female patients (P<0.05). This finding could indicate the biological changes in the cartilage and bone in human brucellosis.

  7. Theoretical investigation, biological evaluation and VEGFR2 kinase studies of metal(II) complexes derived from hydrotris(methimazolyl)borate.

    PubMed

    Jayakumar, S; Mahendiran, D; Srinivasan, T; Mohanraj, G; Kalilur Rahiman, A

    2016-02-01

    The reaction of soft tripodal scorpionate ligand, sodium hydrotris(methimazolyl)borate with M(ClO4)2·6H2O [MMn(II), Ni(II), Cu(II) or Zn(II)] in methanol leads to the cleavage of B-N bond followed by the formation of complexes of the type [M(MeimzH)4](ClO4)2·H2O (1-4), where MeimzH=methimazole. All the complexes were fully characterized by spectro-analytical techniques. The molecular structure of the zinc(II) complex (4) was determined by X-ray crystallography, which supports the observed deboronation reaction in the scorpionate ligand with tetrahedral geometry around zinc(II) ion. The electronic spectra of complexes suggested tetrahedral geometry for manganese(II) and nickel(II) complexes, and square-planar geometry for copper(II) complex. Frontier molecular orbital analysis (HOMO-LUMO) was carried out by B3LYP/6-31G(d) to understand the charge transfer occurring in the molecules. All the complexes exhibit significant antimicrobial activity against Gram (-ve) and Gram (+ve) bacterial as well as fungal strains, which are quite comparable to standard drugs streptomycin and clotrimazole. The copper(II) complex (3) showed excellent free radical scavenging activity against DPPH in all concentration with IC50 value of 30μg/mL, when compared to the other complexes. In the molecular docking studies, all the complexes showed hydrophobic, π-π and hydrogen bonding interactions with BSA. The cytotoxic activity of the complexes against human hepatocellular liver carcinoma (HepG2) cells was assessed by MTT assay, which showed exponential responses toward increasing concentration of complexes.

  8. Investigation of irradiated rats DNA in the presence of Cu(II) chelates of amino acids Schiff bases.

    PubMed

    Karapetyan, N H; Torosyan, A L; Malakyan, M; Bajinyan, S A; Haroutiunian, S G

    2016-01-01

    The new synthesized Cu(II) chelates of amino acids Schiff bases were studied as a potential radioprotectors. Male albino rats of Wistar strain were exposed to X-ray whole-body irradiation at 4.8 Gy. This dose caused 30% mortality of the animals (LD30). The survival of animals exposed to radiation after preliminary administration of 10 mg/kg Cu(II)(Nicotinyl-L-Tyrosinate)2 or Cu(II)(Nicotinyl-L-Tryptophanate)2 prior to irradiation was registered about 80 and 100% correspondingly. Using spectrophotometric melting and agarose gel electrophoresis methods, the differences between the DNA isolated from irradiated rats and rats pretreated with Cu(II) chelates were studied. The fragments of DNA with different breaks were revealed in DNA samples isolated from irradiated animals. While, the repair of the DNA structure was observed for animals pretreated with the Cu(II) chelates. The results suggested that pretreatment of the irradiated rats with Cu(II)(Nicotinyl-L-Tyrosinate)2 and Cu(II)(Nicotinyl-L-Tryptophanate)2 compounds improves the liver DNA characteristics.

  9. Investigation of non-corrin cobalt(II)-containing sites in protein structures of the Protein Data Bank.

    PubMed

    Abriata, Luciano Andres

    2013-04-01

    Protein X-ray structures with non-corrin cobalt(II)-containing sites, either natural or substituting another native ion, were downloaded from the Protein Data Bank and explored to (i) describe which amino acids are involved in their first ligand shells and (ii) analyze cobalt(II)-donor bond lengths in comparison with previously reported target distances, CSD data and EXAFS data. The set of amino acids involved in Co(II) binding is similar to that observed for catalytic Zn(II) sites, i.e. with a large fraction of carboxylate O atoms from aspartate and glutamate and aromatic N atoms from histidine. The computed Co(II)-donor bond lengths were found to depend strongly on structure resolution, an artifact previously detected for other metal-donor distances. Small corrections are suggested for the target bond lengths to the aromatic N atoms of histidines and the O atoms of water and hydroxide. The available target distance for cysteine (Scys) is confirmed; those for backbone O and other donors remain uncertain and should be handled with caution in refinement and modeling protocols. Finally, a relationship between both Co(II)-O bond lengths in bidentate carboxylates is quantified.

  10. Mn(II) Binding and Subsequent Oxidation by the Multicopper Oxidase MnxG Investigated by Electron Paramagnetic Resonance Spectroscopy.

    PubMed

    Tao, Lizhi; Stich, Troy A; Butterfield, Cristina N; Romano, Christine A; Spiro, Thomas G; Tebo, Bradley M; Casey, William H; Britt, R David

    2015-08-26

    The dynamics of manganese solid formation (as MnOx) by the multicopper oxidase (MCO)-containing Mnx protein complex were examined by electron paramagnetic resonance (EPR) spectroscopy. Continuous-wave (CW) EPR spectra of samples of Mnx, prepared in atmosphere and then reacted with Mn(II) for times ranging from 7 to 600 s, indicate rapid oxidation of the substrate manganese (with two-phase pseudo-first-order kinetics modeled using rate coefficients of: k(1obs) = 0.205 ± 0.001 s(-1) and k(2obs) = 0.019 ± 0.001 s(-1)). This process occurs on approximately the same time scale as in vitro solid MnOx formation when there is a large excess of Mn(II). We also found CW and pulse EPR spectroscopic evidence for at least three classes of Mn(II)-containing species in the reaction mixtures: (i) aqueous Mn(II), (ii) a specifically bound mononuclear Mn(II) ion coordinated to the Mnx complex by one nitrogenous ligand, and (iii) a weakly exchange-coupled dimeric Mn(II) species. These findings provide new insights into the molecular mechanism of manganese mineralization.

  11. Measurements of Branching Fractions, Polarizations, and Direct CP-Violation Asymmetries in B to rho K* and B to f0(980) K* Decays

    SciTech Connect

    Aubert, B.

    2006-09-26

    The authors report searches for B-meson decays to the charmless final states {rho}K* and f{sub 0}(980)K* with a sample of 232 million B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at SLAC.

  12. Mean F0 values obtained through standard phrase pronunciation compared with values obtained from the normal work environment: a study on teacher and child voices performed in a preschool environment.

    PubMed

    Lindstrom, Fredric; Ohlsson, Ann-Christine; Sjöholm, Jonas; Waye, Kerstin Persson

    2010-05-01

    Mean fundamental frequency (F(0)) values are often used in research on vocal load. In this study, we examine how the mean F(0) differs when evaluated through pronouncing a standard phrase as compared to the mean F(0) obtained in a real work/play environment. We also examine how the F(0) values change throughout the day. The study was performed in a preschool, nine adult female preschool teachers and 11 children participated. The participants wore a digital recorder equipped with an accelerometer, which was attached to the neck. In the study, the participant first pronounced a standard phrase in a controlled environment; thereafter, the voice was recorded in the environment where both children and adults normally reside throughout the day, denoted by the work/play environment. For each participant, the procedure was repeated four times throughout the day. Analyses showed that the F(0) values of the children's and adult's voices were significantly higher when recorded in the work/play environment as compared to the controlled environment. The average difference was 36 Hz for adults and 24 Hz for children. Previous studies have shown an increase of F(0) over the day for teachers. In this study, an increase between morning and afternoon values was found amounting to 8 Hz for adults and 24 Hz for children. For the child population, this increase was statistically significant. However, the total changes over the day revealed a somewhat more complex scheme, with an increase of F(0) in the morning, a decrease during lunch, and finally an increase in the afternoon. This pattern was verified statistically for the joint child-adult population.

  13. An investigation on new ruthenium(II) hydrazone complexes as anticancer agents and their interaction with biomolecules.

    PubMed

    Alagesan, Mani; Bhuvanesh, Nattamai S P; Dharmaraj, Nallasamy

    2014-04-28

    A new set of ruthenium(II) hydrazone complexes [Ru(H)(CO)(PPh3)2(L)] (1) and [RuCl2(DMSO)2(HL)] (2), with triphenyl phosphine or DMSO as co-ligands was synthesized by reacting benzoyl pyridine furoic acid hydrazone (HL) with [Ru(H)(Cl)(CO)(PPh3)3] and [RuCl2(DMSO)4]. The single crystal X-ray data of complexes 1 and 2 revealed an octahedral geometry around the ruthenium ion in which the hydrazone is coordinated through ON and NN atoms in complexes 1 and 2 respectively. The interaction of the compounds with calf thymus DNA (CT-DNA) has been estimated by absorption and emission titration methods which indicated that the ligand and the complexes interacted with CT-DNA through intercalation. In addition, the DNA cleavage ability of these newly synthesized ruthenium complexes assessed by an agarose gel electrophoresis method demonstrated that complex 2 has a higher DNA cleavage activity than that of complex 1. The binding properties of the free ligand and its complexes with bovine serum albumin (BSA) protein have been investigated using UV-visible, fluorescence and synchronous fluorescence spectroscopic methods which indicated the stronger binding nature of the ruthenium complexes to BSA than the free hydrazone ligand. Furthermore, the cytotoxicity of the compounds examined in vitro on a human cervical cancer cell line (HeLa) and a normal mouse embryonic fibroblasts cell line (NIH 3T3) revealed that complex 2 exhibited a superior cytotoxicity than complex 1 to the cancer cells but was less toxic to the normal mouse embryonic fibroblasts under identical conditions.

  14. Investigation and Control of "Sphere-Like" Buckminsterfullerene C60 and "Disk-Like" Copper(II) Phthalocyanine

    NASA Astrophysics Data System (ADS)

    McAfee, Terry Richard

    Due to the growing global need for cheap, flexible, and portable electronics, numerous research groups from mechanical and electrical engineering, material science, chemistry, and physics have increasingly turned to organic electronics research over the last ˜5--10 years. Largely, the focus of researchers in this growing field have sought to obtain the next record holding device, allowing a heuristic approach of trial and error to become dominant focus of research rather than a fundamental understanding. Rather than working with the latest high performance organic semiconducting materials and film processing techniques, I have chosen to investigate and control the fundamental self-assembly interactions of organic photovoltaic thin films using simplified systems. Specifically, I focus on organic photovoltaic research using two of the oldest and well studies semiconducting materials, namely "sphere-like" electron donor material Buckminsterfullerene C60 and "disklike" electron acceptor material Copper(II) Phthalocyanine. I manufactured samples using the well-known technique of physical vapor deposition using a high vacuum chamber that I designed and built to accommodate my need of precise material deposition control, with codeposition capability. Films were characterized using microscopy and spectroscopy techniques locally at NCSU, including Atomic Force Microscopy, scanning tunneling microscopy, X-ray photoelectron spectroscopy, and Ultraviolet-visible spectroscopy, as well as at National Laboratory based synchrotron x-ray techniques, including Carbon and Nitrogen k-edge Total Electron Yield and Transmission Near Edge X-ray absorption fine structure spectroscopy, Carbon k-edge Resonant Soft x-ray Microscopy, Resonant Soft x-ray reflectivity, and Grazing Incidence Wide-Angle X-ray scattering.

  15. Theoretical investigations of the structures and electronic spectra of Zn(II) and Ni(II) complexes with cyclohexylamine-N-dithiocarbamate

    NASA Astrophysics Data System (ADS)

    Yu, Xiaohan; Wang, Na; He, Hongqing; Wang, Li

    2014-03-01

    The ground-state structures of two ligands cyclohexylamine-N-dithiocarbamate (L) and PPh3 and four complexes [Zn(L)2] (A), [Ni(L)2] (B), [Zn(L)2PPh3] (C), and [Ni(L)2PPh3] (D) are optimized by M06, B3LYP, and B3PW91 methods with the same mixed basis set. As compared with the experimental data of other complexes containing the Ni-P bond, the result obtained by M06/6-31+G(d)-LANL2DZ method is finally regarded as accurate and reliable for this project. Based on the optimized geometries, the compositions of molecular orbitals are analyzed and the absorption spectra are simulated. When one more ligand PPh3 is coordinated, the lowest-lying transition energy presents red-shift; while it shows blue-shift when the metal coordination center change from Ni to Zn with the same ligands. The detailed transition characters related with the absorption spectrum are assigned. In all the key transitions, it is hard to find the contribution from Zn atom. On the contrary, the d orbital of Ni atom contributes a lot for the HOMO and LUMO of complexes B and D. Consequently, the transition characters of Zn(II) and Ni(II) complexes are different.

  16. Subseabed disposal program annual report, January-December 1980. Volume II. Appendices (principal investigator progress reports). Part 1

    SciTech Connect

    Hinga, K.R.

    1981-07-01

    Volume II of the sixth annual report describing the progress and evaluating the status of the Subseabed Disposal Program contains the appendices referred to in Volume I, Summary and Status. Because of the length of Volume II, it has been split into two parts for publication purposes. Part 1 contains Appendices A-Q; Part 2 contains Appendices R-MM. Separate abstracts have been prepared for each appendix for inclusion in the Energy Data Base.

  17. Synthesis, crystal structure, spectroscopic investigations and DFT calculations of the copper(II) complex of 4-(Trifluoromethyl)pyridine-2-carboxylic acid

    NASA Astrophysics Data System (ADS)

    Vural, Hatice; Orbay, Metin

    2017-10-01

    A novel polymeric complex of Cu(II) ion, [Cu(tfpc)2]n [tfpc: 4-(Trifluoromethyl)pyridine-2-carboxylate] has been prepared and characterized spectroscopically (by FT-IR) and structurally (by single-crystal XRD). The geometry around the Cu(II) center can be described as square planar made by tfpc ligand having nitrogen and oxygen atoms. Additionally, the Cu(II) complex has a one-dimensional double-bridged polymeric structure in which Cu(II) ions are bridged by two oxygen atoms of adjacent planes. The crystal packing has been stabilized by Csbnd H⋯O intra and intermolecular hydrogen bonds. The molecular structure of the Cu(II) complex has been optimized using the Density Functional Theory (DFT) B3LYP, B3PW91 and PBEPBE levels with 6-311+G(d,p) basis set. The calculated electronic spectra have been explained using the time dependent DFT (TD-DFT) method by applying the polarized continuum model (PCM). The vibrational spectral data have been calculated and compared with experimental ones. The non-linear optical (NLO) properties of the title compound have been investigated using the DFT method with three different levels. Natural Bond Orbital (NBO) property of the Cu(II) complex has been performed by the B3LYP density functional and the 6-311+G(d,p) basis set.

  18. Co-sequestration of Zn(II) and phosphate by γ-Al2O3: From macroscopic to microscopic investigation.

    PubMed

    Ren, Xuemei; Tan, Xiaoli; Hayat, Tasawar; Alsaedi, Ahmed; Wang, Xiangke

    2015-10-30

    Little information is available concerning co-sorbing oxyanion and metal contaminants in the environment, yet in most metal-contaminated areas, co-contamination by phosphate is common. In this study, the mutual effects of phosphate and Zn(II) on their interaction with γ-Al2O3 are investigated by batch experiments and X-ray absorption fine structure spectroscopy (XAFS) technique. The results show that the co-sorption of phosphate on γ-Al2O3 modifies both the extent of Zn(II) sorption and the local atomic structures of sorbed Zn(II) ions. Multiple mechanisms are involved in Zn(II) retention in the presence of phosphate, including electrostatic interaction, binary and ternary surface complexation, and the formation of Zn(II)-phosphate polynuclear complexes. At pH 6.5, type III ternary surface complexation occurs concurrently with binary Zn-alumina surface complexation at low phosphate concentrations, whereas the formation of type III ternary surface complexes is promoted as the phosphate concentration increases. With further increasing phosphate concentration, Zn(II)-phosphate polynuclear complexes are formed. At pH 8.0, Zn dominantly forms type III ternary surface complexes in the presence of phosphate. The results of this study indicate the variability of Zn complexation on oxide surface and the importance of combining macroscopic observations with XAFS capable of determining metal complex formation mechanism for ternary system. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Investigation of a Cu(II)-poly(gamma-glutamic acid) complex in aqueous solution and its insulin-mimetic activity.

    PubMed

    Karmaker, Subarna; Saha, Tapan K; Sakurai, Hiromu

    2007-04-10

    The complexation between cupric ions (Cu(II)) and poly(gamma-glutamic acid) (gamma-PGA) in aqueous solutions (pH 3-11) has been studied by UV-visible absorption and electron spin resonance (ESR) techniques. Formation of the Cu(II)-gamma-PGA complex is confirmed by the observation of the blue shift of the absorption band in the visible region, anisotropic line shapes in the ESR spectrum at room temperature, and a computer simulation of the visible absorption spectrum of the complex. The structure of the Cu(II)-gamma-PGA complex, depending on the pH, has been determined. The in vitro insulin-mimetic activity of the Cu(II)-gamma-PGA complex is examined by determining both inhibition of free fatty acid release and glucose uptake in isolated rat adipocytes treated with epinephrine, in which the concentration of the Cu(II)-gamma-PGA complex for 50% inhibition of free fatty acid release is very similar to that of CuSO4. However, it is significantly lower than that of a previously reported insulin-mimetic bis(3-hydroxypicolinato)copper(II), [Cu(3hpic)2], complex.

  20. Investigation of the biosorption characteristics of lead(II) ions onto Symphoricarpus albus: Batch and dynamic flow studies.

    PubMed

    Akar, Sibel Tunali; Gorgulu, Asli; Anilan, Burcu; Kaynak, Zerrin; Akar, Tamer

    2009-06-15

    This work reports the results of the study for lead(II) binding by the natural and low cost biosorbent Symphoricarpus albus. Batch biosorption experiments demonstrated the high rate of lead(II) biosorption and the kinetic data were successfully described by a pseudo-second-order model. Biosorption of lead(II) onto S. albus biomass showed a pH-dependent profile and lead(II) biosorption was higher when pH or temperature was increased. As much as 88.5% removal of lead(II) is also possible in the multi-metal mixture. The Langmuir isotherm better fits the biosorption data and the monolayer biosorption capacity was 3.00 x 10(-4) mol g(-1) at 45 C. The biomass was characterized with FTIR and SEM analysis. Desorption studies revealed that the natural biomass could be regenerated using 10mM HNO(3) solution with about 99% recovery and reused in five biosorption-desorption cycles. Therefore, S. albus which is cheap, highly selective and easily regenerable seems to be a promising substrate to entrap lead(II) ions in aqueous solutions.

  1. Final phase I report and phase II work plan : QuickSite{reg_sign} investigation, Centralia, Kansas.

    SciTech Connect

    LaFreniere, L. M.

    2003-03-01

    /hydrogeologic model, objectives of the Phase I investigation, and a brief description of the sections contained in this report. Section 2 describes the investigative methods used during the Phase I investigation. Section 3 presents all of the data obtained during the investigation. Section 4 describes the interpretation of the pertinent data used to meet the technical objectives of the investigation, including the contaminant migration pathways in soil and groundwater. A summary of the findings is also provided in Section 4. Section 5 presents the conclusions of the investigation relative to the technical objectives and outlines recommendations for Phase II. To streamline the reporting process, materials from the Work Plan (Argonne 2002a) and relevant sections of the Master Work Plan (Argonne 2002b) are not repeated in detail in this report. Consequently, these documents must also be consulted to obtain the complete details of the Phase I investigative program.

  2. Preliminary Results of an Altitude-Wind-Tunnel Investigation of a TG-100A Gas Turbine-Propeller Engine II - Windmilling Characteristics

    NASA Technical Reports Server (NTRS)

    Conrad, E. W.; Durham, J. D.

    1947-01-01

    An investigation was conducted to determine the operational and performance characteristics of the TG-100A gas turbine-propeller engine II. Windmilling characteristics were deterined for a range of altitudes from 5000 to 35,000 feet, true airspeeds from 100 to 273 miles per hour, and propeller blade angles from 4 degrees to 46 degrees.

  3. TECHNICAL REPORT ON TECHNOLOGICALLY ENHANCED NATURALLY OCCURRING RADIOACTIVE MATERIALS FROM URANIUM MINING, VOLUME II: INVESTIGATION OF POTENTIAL HEALTH, GEOGRAPHIC, AND ENVIRONMENTAL ISSUES OF ABANDONED URANIUM MINES

    EPA Science Inventory

    Volume II investigates the potential radiogenic risks from abandoned uranium mines and evaluates which may pose the greatest hazards to members of the public and to the environment. The intent of this report is to identify who may be most likely to be exposed to wastes at small a...

  4. TECHNICAL REPORT ON TECHNOLOGICALLY ENHANCED NATURALLY OCCURRING RADIOACTIVE MATERIALS FROM URANIUM MINING, VOLUME II: INVESTIGATION OF POTENTIAL HEALTH, GEOGRAPHIC, AND ENVIRONMENTAL ISSUES OF ABANDONED URANIUM MINES

    EPA Science Inventory

    Volume II investigates the potential radiogenic risks from abandoned uranium mines and evaluates which may pose the greatest hazards to members of the public and to the environment. The intent of this report is to identify who may be most likely to be exposed to wastes at small a...

  5. Measurement of the ratio B (Bs0 → J / ψf0 (980)) / B (Bs0 → J / ψϕ (1020)) in pp collisions at √{ s} = 7 TeV

    NASA Astrophysics Data System (ADS)

    Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Bergauer, T.; Dragicevic, M.; Erö, J.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hartl, C.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Rabady, D.; Rahbaran, B.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Treberer-Treberspurg, W.; Waltenberger, W.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Alderweireldt, S.; Bansal, S.; Cornelis, T.; De Wolf, E. A.; Janssen, X.; Knutsson, A.; Lauwers, J.; Luyckx, S.; Ochesanu, S.; Rougny, R.; Van De Klundert, M.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D'Hondt, J.; Daci, N.; Heracleous, N.; Keaveney, J.; Lowette, S.; Maes, M.; Olbrechts, A.; Python, Q.; Strom, D.; Tavernier, S.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G. P.; Villella, I.; Caillol, C.; Clerbaux, B.; De Lentdecker, G.; Dobur, D.; Favart, L.; Gay, A. P. R.; Grebenyuk, A.; Léonard, A.; Mohammadi, A.; Perniè, L.; Randle-conde, A.; Reis, T.; Seva, T.; Thomas, L.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Zenoni, F.; Adler, V.; Beernaert, K.; Benucci, L.; Cimmino, A.; Costantini, S.; Crucy, S.; Fagot, A.; Garcia, G.; Mccartin, J.; Ocampo Rios, A. A.; Poyraz, D.; Ryckbosch, D.; Salva Diblen, S.; Sigamani, M.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Beluffi, C.; Bruno, G.; Castello, R.; Caudron, A.; Ceard, L.; Da Silveira, G. G.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Jafari, A.; Jez, P.; Komm, M.; Lemaitre, V.; Nuttens, C.; Pagano, D.; Perrini, L.; Pin, A.; Piotrzkowski, K.; Popov, A.; Quertenmont, L.; Selvaggi, M.; Vidal Marono, M.; Vizan Garcia, J. M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Aldá Júnior, W. L.; Alves, G. A.; Brito, L.; Correa Martins Junior, M.; Dos Reis Martins, T.; Molina, J.; Mora Herrera, C.; Pol, M. E.; Rebello Teles, P.; Carvalho, W.; Chinellato, J.; Custódio, A.; Da Costa, E. M.; De Jesus Damiao, D.; De Oliveira Martins, C.; Fonseca De Souza, S.; Malbouisson, H.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Prado Da Silva, W. L.; Santaolalla, J.; Santoro, A.; Sznajder, A.; Tonelli Manganote, E. J.; Vilela Pereira, A.; Bernardes, C. A.; Dogra, S.; Fernandez Perez Tomei, T. R.; Gregores, E. M.; Mercadante, P. G.; Novaes, S. F.; Padula, Sandra S.; Aleksandrov, A.; Genchev, V.; Hadjiiska, R.; Iaydjiev, P.; Marinov, A.; Piperov, S.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Vutova, M.; Dimitrov, A.; Glushkov, I.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Chen, M.; Cheng, T.; Du, R.; Jiang, C. H.; Plestina, R.; Romeo, F.; Tao, J.; Wang, Z.; Asawatangtrakuldee, C.; Ban, Y.; Liu, S.; Mao, Y.; Qian, S. J.; Wang, D.; Xu, Z.; Zhang, L.; Zou, W.; Avila, C.; Cabrera, A.; Chaparro Sierra, L. F.; Florez, C.; Gomez, J. P.; Gomez Moreno, B.; Sanabria, J. C.; Godinovic, N.; Lelas, D.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Kadija, K.; Luetic, J.; Mekterovic, D.; Sudic, L.; Attikis, A.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P. A.; Rykaczewski, H.; Bodlak, M.; Finger, M.; Finger, M.; Assran, Y.; Ellithi Kamel, A.; Mahmoud, M. A.; Radi, A.; Kadastik, M.; Murumaa, M.; Raidal, M.; Tiko, A.; Eerola, P.; Voutilainen, M.; Härkönen, J.; Karimäki, V.; Kinnunen, R.; Kortelainen, M. J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Wendland, L.; Talvitie, J.; Tuuva, T.; Besancon, M.; Couderc, F.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J. L.; Favaro, C.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Rander, J.; Rosowsky, A.; Titov, M.; Baffioni, S.; Beaudette, F.; Busson, P.; Chapon, E.; Charlot, C.; Dahms, T.; Dalchenko, M.; Dobrzynski, L.; Filipovic, N.; Florent, A.; Granier de Cassagnac, R.; Mastrolorenzo, L.; Miné, P.; Naranjo, I. N.; Nguyen, M.; Ochando, C.; Ortona, G.; Paganini, P.; Regnard, S.; Salerno, R.; Sauvan, J. B.; Sirois, Y.; Veelken, C.; Yilmaz, Y.; Zabi, A.; Agram, J.-L.; Andrea, J.; Aubin, A.; Bloch, D.; Brom, J.-M.; Chabert, E. C.; Collard, C.; Conte, E.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Goetzmann, C.; Le Bihan, A.-C.; Skovpen, K.; Van Hove, P.; Gadrat, S.; Beauceron, S.; Beaupere, N.; Bernet, C.; Boudoul, G.; Bouvier, E.; Brochet, S.; Carrillo Montoya, C. A.; Chasserat, J.; Chierici, R.; Contardo, D.; Courbon, B.; Depasse, P.; El Mamouni, H.; Fan, J.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Pequegnot, A. L.; Perries, S.; Ruiz Alvarez, J. D.; Sabes, D.

    2016-05-01

    A measurement of the ratio of the branching fractions of the Bs0 meson to J / ψf0 (980) and to J / ψϕ (1020) is presented. The J / ψ, f0 (980), and ϕ (1020) are observed through their decays to μ+μ-, π+π-, and K+K-, respectively. The f0 and the ϕ are identified by requiring |Mπ+π- - 974 MeV | < 50 MeV and |MK+K- - 1020 MeV | < 10 MeV. The analysis is based on a data sample of pp collisions at a centre-of-mass energy of 7 TeV, collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 5.3 fb-1. The measured ratio is B(Bs0 → J / ψf0) B (f0 →π+π-)/B (Bs0 → J / ψϕ) B (ϕ →K+K-) = 0.140 ± 0.008 (stat) ± 0.023 (syst), where the first uncertainty is statistical and the second is systematic.

  6. Investigation on M-class Flare-Associated Coronal Mass Ejections with and Without DH Type II Radio Bursts

    NASA Astrophysics Data System (ADS)

    Selvarani, G.; Shanmugaraju, A.; Vrsnak, Bojan; Lawrance, M. Bendict

    2017-06-01

    We perform a statistical analysis on 157 M-class soft X-ray flares observed during 1997 - 2014 with and without deca-hectometric (DH) type II radio bursts aiming at the reasons for the non-occurrence of DH type II bursts in certain events. All the selected events are associated with halo Coronal Mass Ejections (CMEs) detected by the Solar and Heliospheric Observatory (SOHO) / Large Angle Spectrometric and COronograph (LASCO). Out of 157 events, 96 (61%; "Group I") events are associated with a DH type II burst observed by the Radio and Plasma Wave (WAVES) experiment onboard the Wind spacecraft and 61 (39%; "Group II") events occur without a DH type II burst. The mean CME speed of Group I is 1022 km/s and that of Group II is 647 km/s. It is also found that the properties of the selected M-class flares such as flare intensity, rise time, duration and decay time are greater for the DH associated flares than the non-DH flares. Group I has a slightly larger number (56%) of western events than eastern events (44%), whereas Group II has a larger number of eastern events (62%) than western events (38%). We also compare this analysis with the previous study by Lawrance, Shanmugaraju, and Vršnak ( Solar Phys. 290, 3365L, 2015) concerning X-class flares and confirm that high-intensity flares (X-class and M-class) have the same trend in the CME and flare properties. Additionally we consider aspects like acceleration and the possibility of CME-streamer interaction. The average deceleration of CMEs with DH type II bursts is weaker (a = - 4.39 m/s2) than that of CMEs without a type II burst (a = -12.21 m/s2). We analyze the CME-streamer interactions for Group I events using the model proposed by Mancuso and Raymond ( Astron. Astrophys. 413, 363, 2004) and find that the interaction regions are the most probable source regions for DH type II radio bursts.

  7. Catalytic mechanism of heparinase II investigated by site-directed mutagenesis and the crystal structure with its substrate.

    PubMed

    Shaya, David; Zhao, Wenjing; Garron, Marie-Line; Xiao, Zhongping; Cui, Qizhi; Zhang, Zhenqing; Sulea, Traian; Linhardt, Robert J; Cygler, Miroslaw

    2010-06-25

    Heparinase II (HepII) is an 85-kDa dimeric enzyme that depolymerizes both heparin and heparan sulfate glycosaminoglycans through a beta-elimination mechanism. Recently, we determined the crystal structure of HepII from Pedobacter heparinus (previously known as Flavobacterium heparinum) in complex with a heparin disaccharide product, and identified the location of its active site. Here we present the structure of HepII complexed with a heparan sulfate disaccharide product, proving that the same binding/active site is responsible for the degradation of both uronic acid epimers containing substrates. The key enzymatic step involves removal of a proton from the C5 carbon (a chiral center) of the uronic acid, posing a topological challenge to abstract the proton from either side of the ring in a single active site. We have identified three potential active site residues equidistant from C5 and located on both sides of the uronate product and determined their role in catalysis using a set of defined tetrasaccharide substrates. HepII H202A/Y257A mutant lost activity for both substrates and we determined its crystal structure complexed with a heparan sulfate-derived tetrasaccharide. Based on kinetic characterization of various mutants and the structure of the enzyme-substrate complex we propose residues participating in catalysis and their specific roles.

  8. Catalytic Mechanism of Heparinase II Investigated by Site-directed Mutagenesis and the Crystal Structure with Its Substrate

    SciTech Connect

    Shaya, D.; Zhao, W; Garron, M; Xiao, Z; Cui, Q; Zhang, Z; Sulea, T; Linhardt, R; Cygler, M

    2010-01-01

    Heparinase II (HepII) is an 85-kDa dimeric enzyme that depolymerizes both heparin and heparan sulfate glycosaminoglycans through a {beta}-elimination mechanism. Recently, we determined the crystal structure of HepII from Pedobacter heparinus (previously known as Flavobacterium heparinum) in complex with a heparin disaccharide product, and identified the location of its active site. Here we present the structure of HepII complexed with a heparan sulfate disaccharide product, proving that the same binding/active site is responsible for the degradation of both uronic acid epimers containing substrates. The key enzymatic step involves removal of a proton from the C5 carbon (a chiral center) of the uronic acid, posing a topological challenge to abstract the proton from either side of the ring in a single active site. We have identified three potential active site residues equidistant from C5 and located on both sides of the uronate product and determined their role in catalysis using a set of defined tetrasaccharide substrates. HepII H202A/Y257A mutant lost activity for both substrates and we determined its crystal structure complexed with a heparan sulfate-derived tetrasaccharide. Based on kinetic characterization of various mutants and the structure of the enzyme-substrate complex we propose residues participating in catalysis and their specific roles.

  9. Solution structure investigation of Ru(II) complex ion pairs: quantitative NOE measurements and determination of average interionic distances.

    PubMed

    Zuccaccia, C; Bellachioma, G; Cardaci, G; Macchioni, A

    2001-11-07

    The structure of the Ru(II) ion pairs trans-[Ru(COMe)[(pz(2))CH(2)](CO)(PMe(3))(2)]X (X(-) = BPh(4)(-), 1a; BPh(3)Me(-), 1b; BPh(3)(n-Bu)(-), 1c; BPh(3)(n-Hex)(-), 1d; B(3, 5-(CF(3))(2)(C(6)H(3)))(4)(-), 1e; PF(6)(-), 1f; and BF(4)(-), 1g; pz = pyrazol-1-yl-ring) was investigated in solution from both a qualitative (chloroform-d, methylene chloride-d(2), nithromethane-d(3)) and quantitative (methylene chloride-d(2)) point of view by performing 1D- and 2D-NOE NMR experiments. In particular, the relative anion-cation localization (interionic structure) was qualitatively determined by (1)H-NOESY and (19)F, (1)H-HOESY (heteronuclear Overhauser effect spectroscopy) NMR experiments. The counteranion locates close to the peripheral protons of the bispyrazolyl ligand independent of its nature and that of the solvent. In complexes 1c and 1d bearing unsymmetrical counteranions, the aliphatic chain points away from the metal center as indicated by the absence of NOE between the terminal Me group and any cationic protons. An estimation of the average interionic distances in solution was obtained by the quantification of the NOE build-up versus the mixing time under the assumption that the interionic and intramolecular correlation times (tau(c)) are the same. Such an assumption was checked by the experimental measurements of tau(c) from both the dipolar contribution to the carbon-13 longitudinal relaxation time T(DD-1)and the comparison of the intramolecular and interionic cross relaxation rate constant (sigma) dependence on the temperature. Both the methodologies indicate that anion and cation have comparable tau(c) values. The determined correlation time values were compared with those obtained for the neutral trans-[Ru(COMe)[(pz(2))BH(2)](CO)(PMe(3))(2)] complex (2), isosteric with the cation of 1. They were significantly shorter (approximately 3.8 times), indicating that the main contribution to dipolar relaxation processes comes from the overall ion pair rotation. As a

  10. Protein Binding and the Electronic Properties of Iron(II) Complexes: An Electrochemical and Optical Investigation of Outer Sphere Effects

    SciTech Connect

    Barker, Kylie D.; Eckermann, Amanda L.; Sazinsky, Matthew H.; Hartings, Matthew R.; Abajian, Carnie; Georganopoulou, Dimitra; Ratner, Mark A.; Rosenzweig, Amy C.; Meade, Thomas J.

    2010-11-17

    Metalloenzymes and electron transfer proteins influence the electrochemical properties of metal cofactors by controlling the second-sphere environment of the protein active site. Properties that tune this environment include the dielectric constant, templated charge structure, van der Waals interactions, and hydrogen bonds. By systematically varying the binding of a redox-active ligand with a protein, we can evaluate how these noncovalent interactions alter the electronic structure of the bound metal complex. For this study, we employ the well-characterized avidin-biotin conjugate as the protein-ligand system, and have synthesized solvatochromic biotinylated and desthiobiotinylated iron(II) bipyridine tetracyano complexes ([Fe(BMB)(CN){sub 4}]{sup 2-} (1) and [Fe(DMB)(CN){sub 4}]{sup 2-} (2)). The binding affinities of 1 and 2 with avidin are 3.5 x 10{sup 7} M{sup -1} and 1.5 x 10{sup 6} M{sup -1}, respectively. The redox potentials of 1 and 2 (333 mV and 330 mV) shift to 193 mV and 203 mV vs Ag/AgCl when the complex is bound to avidin and adsorbed to a monolayer-coated gold electrode. Upon binding to avidin, the MLCT1 band red-shifts 20 nm for 1 and 10 nm for 2. Similarly, the MLCT2 band for 1 red-shifts 7 nm and the band for 2 red-shifts 6 nm. For comparison, the electronic properties of 1 and 2 were investigated in organic solvents, and similar shifts in the MLCT bands and redox potentials were observed. An X-ray crystal structure of 1 bound to avidin was obtained, and molecular dynamics simulations were performed to analyze the protein environment of the protein-bound transition metal complexes. Our studies demonstrate that changes in the binding affinity of a ligand-receptor pair influence the outer-sphere coordination of the ligand, which in turn affects the electronic properties of the bound complex.

  11. Part I. Inviscid, Swirling Flows and Vortex Breakdown. Part II. a Numerical Investigation of the Lundgren Turbulence Model.

    NASA Astrophysics Data System (ADS)

    Buntine, James Douglas

    Part I. A study of the behaviour of an inviscid, swirling fluid is performed. This flow can be described by the Squire-Long equation if the constraints of time -independence and axisymmetry are invoked. The particular case of flow through a diverging pipe is selected and a study is conducted to determine over what range of parameters (both pipe inlet conditions and geometry) does a (unique) solution exist. The work is performed with a view to understanding how the phenomenon of vortex breakdown develops. Experiments and previous numerical studies have indicated that the flow is sensitive to boundary conditions particularly at the pipe inlet. A "quasi-cylindrical" simplification of the Squire-Long equation is compared with the more complete model and shown to be able to account for most of its behaviour. An advantage of this latter representation is the relatively undetailed description of the flow geometry it requires in order to calculate a solution. "Criticality" or the ability of small disturbances to propagate upstream is related to results of the quasi -cylindrical and axisymmetric flow models. This leads to an examination of claims made by researchers such as Benjamin and Hall concerning the interrelationship between "failure" of the quasi-cylindrical model and the occurrence of a "critical" flow state. Other criteria for predicting the onset of vortex breakdown are considered in the context of the model employed, particularly those of Brown & Lopez and Spall, Gatski & Grosch. Part II. Lundgren (1982) developed an analytical model for homogeneous turbulence based on a collection of contracting spiral vortices each embedded in an axisymmetric strain field. Using asymptotic approximations he was able to deduce the Kolmogorov k^{-5/3} behaviour for inertial scales in the turbulence energy spectrum. Pullin & Saffman have enlarged upon his work to make a number of predictions about the behaviour of turbulence described by the model. This work investigates the

  12. Investigation of uptake and retention of atmospheric Hg(II) by boreal forest plants using stable Hg isotopes.

    PubMed

    Graydon, Jennifer A; St Louis, Vincent L; Hintelmann, Holger; Lindberg, Steve E; Sandilands, Ken A; Rudd, John W M; Kelly, Carol A; Tate, Michael T; Krabbenhoft, Dave P; Lehnherr, Igor

    2009-07-01

    Although there is now a general consensus among mercury (Hg) biogeochemists that increased atmospheric inputs of inorganic Hg(II) to lakes and watersheds can result in increased methylmercury (MeHg) concentrations in fish, researchers still lack kinetic data describing the movement of Hg from the atmosphere, through watershed and lake ecosystems, and into fish. The use of isotopically enriched Hg species in environmental studies now allows experimentally applied new Hg to be distinguished from ambient Hg naturally present in the system. Four different enriched stable Hg(II) isotope "spikes" were applied sequentially over four years to the ground vegetation of a microcatchment at the Experimental Lakes Area (ELA) in the remote boreal forest of Canada to examine retention of Hg(II) following deposition. Areal masses of the spikes and ambient THg (all forms of Hg in a sample) were monitored for eight years, and the pattern of spike retention was used to estimate retention of newly deposited ambient Hg within the ground vegetation pool. Fifty to eighty percent of applied spike Hg was initially retained by ground vegetation. The areal mass of spike Hg declined exponentially over time and was best described by a first-order process with constants(k) ranging between 9.7 x 10(-40 day(-1) and 11.6 x 10(-4) day(-1). Average halflife (t1/2) of spike Hg within the ground vegetation pool (+/-S.D.) was 704 +/- 52 days. This retention of new atmospheric Hg(II) by vegetation delays movement of new Hg(II) into soil, runoff, and finally into adjacent lakes. Ground-applied Hg(II) spikes were not detected in tree foliage and litterfall, indicating that stomatal and/or root uptake of previously deposited Hg (i.e., "recycled" from ground vegetation or soil Hg pools) were likely not large sources of foliar Hg under these experimental conditions.

  13. Investigation of uptake and retention of atmospheric Hg(II) by boreal forest plants using stable Hg isotopes

    USGS Publications Warehouse

    Graydon, J.A.; St. Louis, V.L.; Hintelmann, H.; Lindberg, S.E.; Sandilands, K.A.; Rudd, J.W.M.; Kelly, C.A.; Tate, M.T.; Krabbenhoft, D.P.; Lehnherr, I.

    2009-01-01

    Although there is now a general consensus among mercury (Hg) biogeochemists that increased atmospheric inputs of inorganic Hg(II) to lakes and watersheds can result in increased methylmercury (MeHg) concentrations in fish, researchers still lack kinetic data describing the movement of Hg from the atmosphere, through watershed and lake ecosystems, and into fish. The use of isotopically enriched Hg species in environmental studies now allows experimentally applied new Hg to be distinguished from ambient Hg naturally present in the system. Four different enriched stable Hg(II) isotope "spikes" were applied sequentially over four years to the ground vegetation of a microcatchment at the Experimental Lakes Area (ELA) in the remote boreal forest of Canada to examine retention of Hg(II) following deposition. Areal masses of the spikes and ambient THg (all forms of Hg in a sample) were monitored for eight years, and the pattern of spike retention was used to estimate retention of newly deposited ambient Hg within the ground vegetation pool. Fifty to eighty percent of applied spike Hg was initially retained by ground vegetation. The areal mass of spike Hg declined exponentially over time and was best described by a first-order process with constants (k) ranging between 9.7 ?? 10-4 day -1 and 11.6 ?? 10-4 day-1. Average half-life (t1/2) of spike Hg within the ground vegetation pool (??S.D.) was 704 ?? 52 days. This retention of new atmospheric Hg(II) by vegetation delays movement of new Hg(II) into soil, runoff, and finally into adjacent lakes. Ground-applied Hg(II) spikes were not detected in tree foliage and litterfall, indicating that stomatal and/or root uptake of previously deposited Hg (i.e., "recycled" from ground vegetation or soil Hg pools) were likely not large sources of foliar Hg under these experimental conditions. ?? 2009 American Chemical Society.

  14. Spectroscopic investigation into the interaction of a diazacyclam-based macrocyclic copper(ii) complex with bovine serum albumin.

    PubMed

    Shahabadi, Nahid; Hakimi, Mohammad; Morovati, Teimoor; Hadidi, Saba; Moeini, Keyvan

    2017-02-01

    Cyclam-based ligands and their complexes are known to show antitumor activity. This study was undertaken to examine the interaction of a diazacyclam-based macrocyclic copper(II) complex with bovine serum albumin (BSA) under physiological conditions. The interactions of different metal-based drugs with blood proteins, especially those with serum albumin, may affect the concentration and deactivation of metal drugs, and thereby influence their availability and toxicity during chemotherapy. In this vein, several spectral methods including UV-vis absorption, fluorescence and circular dichroism (CD) spectroscopy techniques were used. Spectroscopic analysis of the fluorescence quenching confirmed that the Cu(II) complex quenched BSA fluorescence intensity by a dynamic mechanism. In order to further determine the quenching mechanism, an analysis of Stern-Volmer plots at various concentrations of BSA was carried out. It was found that the KSV value increased with the BSA concentration. It was suggested that the fluorescence quenching process was a dynamic quenching rather than a static quenching mechanism. Based on Förster's theory, the average binding distance between the Cu(II) complex and BSA (r) was found to be 4.98 nm; as the binding distance was less than 8 nm, energy transfer from BSA to the Cu(II) complex had a high possibility of occurrence. Thermodynamic parameters (positive ΔH and ΔS values) and measurement of competitive fluorescence with 1-anilinonaphthalene-8-sulphonic acid (1,8-ANS) indicated that hydrophobic interaction plays a major role in the Cu(II) complex interaction with BSA. A Job's plot of the results confirmed that there was one binding site in BSA for the Cu(II) complex (1:1 stoichiometry). The site marker competitive experiment confirmed that the Cu(II) complex was located in site I (subdomain IIA) of BSA. Finally, CD data indicated that interaction of the Cu(II) complex with BSA caused a small increase in the α-helical content. Copyright

  15. Investigation of the photophysical and photochemical properties of peripherally tetra-substituted water-soluble zwitterionic and cationic zinc(ii) phthalocyanines.

    PubMed

    Çolak, Senem; Durmuş, Mahmut; Yıldız, Salih Zeki

    2016-06-21

    In this study, 4-{4-[N-((3-dimethylamino)propyl)amide]phenoxy}phthalonitrile () and its zinc(ii) phthalocyanine derivative () were synthesized for the first time. 4-(N-((3-Dimethylamino)propyl)amide)phenoxy substituted zinc(ii) phthalocyanine () was converted to its water-soluble sulfobetaine (), betaine () and N-oxide () containing zwitterionic and quaternized cationic () derivatives. All newly synthesized compounds () were characterized by the combination of UV-vis, FT-IR, (1)H NMR, mass spectroscopy techniques and elemental analysis. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen quantum yields) properties were investigated in DMSO for all the synthesized zinc(ii) phthalocyanines () and in both DMSO and aqueous solutions for zwitterionic and cationic phthalocyanines () for the specification of their capability as photosensitizers in photodynamic therapy (PDT). The binding behavior of water soluble phthalocyanines () to the bovine serum albumin protein was also examined for the determination of their transportation ability in the blood stream.

  16. Synthesis, characterization and investigation of electrochemical and spectroelectrochemical properties of peripherally tetra 4-phenylthiazole-2-thiol substituted metal-free, zinc(II), copper(II) and cobalt(II) phthalocyanines

    NASA Astrophysics Data System (ADS)

    Demirbaş, Ümit; Akçay, Hakkı Türker; Koca, Atıf; Kantekin, Halit

    2017-08-01

    In this study novel peripherally tetra 4-phenylthiazole-2-thiol substituted metal-free phthalocyanine (4) and its zinc(II) (5), copper(II) (6) and cobalt(II) (7) derivatives were synthesized and characterized by a combination of various spectroscopic techniques such as FT-IR, 1H-NMR, UV-vis and MALDI-TOF mass. Electrochemical characterizations of metallo-phthalocyanine complexes were conducted by voltammetric and in situ spectroelectrochemical measurements. CoIIPc went [CoIIPc-2]/[CoIPc-2]1-, [CoIPc-2]1-/[CoIPc-3]2-, [CoIPc-3]2-/[CoIPc-4]3- and [CoIIPc-2]/[CoIIPc-2]1+ reduction and oxidation processes respectively. Differently ZnIIPc only showed four ligand-based reductions and two ligand based oxidation processes.

  17. Multiple Intelligences and ESL Teaching and Learning: An Investigation in KG II Classrooms in One Private School in Beirut, Lebanon

    ERIC Educational Resources Information Center

    Ghamrawi, Norma

    2014-01-01

    This study examined teachers' use of the Multiple Intelligences Theory on vocabulary acquisition by preschoolers during English as a second language (ESL) classes in a K-12 school in Lebanon. Eighty kindergartners (KG II, aged 5 years) and eight teachers constituted the sample. The study used mixed methods, including observations of videotaped…

  18. Spectrophotometric investigation on the kinetics of oxidation of adrenaline by dioxygen of μ-dioxytetrakis(histidinato)-dicobalt(II) complex

    NASA Astrophysics Data System (ADS)

    Rafiquee, M. Z. A.; Siddiqui, Masoom R.; Ali, Mohd. Sajid; Al-Lohedan, Hamad A.

    The cobalt(II)histidine complex binds molecular oxygen reversibly to form an oxygen adduct complex, μ-dioxytetrakis-(histidinato)dicobalt(II). The molecular oxygen can be released from the oxygenated complex by heating it or by passing N2, He or Ar gas through its solution. μ-Dioxytetrakis-(histidinato)dicobalt(II) complex oxidizes adrenaline into leucoadrenochrome at 25 °C while at higher temperature (>40 °C) adrenochrome with λmax at 490 nm is formed. The rate of formation of leucoadrenochrome was found to be independent of [bis(histidinato)cobalt(II)]. The rate of reaction for the formation of leucoadrenochrome and adrenochrome increased with the increase in [adrenaline] at its lower concentration but become independent at higher concentration. Similarly, the rate of formation of both leucoadrenochrome and adrenochrome was linearly dependent upon [NaOH]. The values of activation parameters i.e. ΔEa, ΔH‡ and ΔS‡ for the formation of leucoadrenochrome are reported.

  19. Multiple Intelligences and ESL Teaching and Learning: An Investigation in KG II Classrooms in One Private School in Beirut, Lebanon

    ERIC Educational Resources Information Center

    Ghamrawi, Norma

    2014-01-01

    This study examined teachers' use of the Multiple Intelligences Theory on vocabulary acquisition by preschoolers during English as a second language (ESL) classes in a K-12 school in Lebanon. Eighty kindergartners (KG II, aged 5 years) and eight teachers constituted the sample. The study used mixed methods, including observations of videotaped…

  20. Investigation of X-class Flare-Associated Coronal Mass Ejections with and without DH Type II Radio Bursts

    NASA Astrophysics Data System (ADS)

    Lawrance, M. Bendict; Shanmugaraju, A.; Vršnak, Bojan

    2015-11-01

    A statistical analysis of 135 out of 141 X-class flares observed during 1997 - 2012 with and without deca-hectometric (DH) type II radio bursts has been performed. It was found that 79 events (X-class flares and coronal mass ejections - Group I) were associated with DH type II radio bursts and 62 X-class flare events were not. Out of these 62 events without DH type IIs, 56 events (Group II) have location information, and they were selected for this study. Of these 56 events, only 32 were associated with CMEs. Most of the DH-associated X-class events ({˜} 79 %) were halo CMEs, in contrast to 14 % in Group II. The average CME speed of the X-class flares associated with DH type IIs is 1555 km s-1, which is nearly twice that of the X-class flare-associated CMEs without DH event (744 km s-1). The X-class flares associated with DH radio bursts have a mean flare intensity (3.63 × 10^{-4} W m^{-2}) that is 38 % greater than that of X-class flares without DH radio bursts (2.23 × 10^{-4} W m^{-2}). In addition to the greater intensity, it is also found that the the duration and rise time of flares associated with DH radio emission (DH flares) is more than twice than that of the flares without DH radio emission. When the events were further divided into two categories with respect to their source locations in eastern and western regions, 65 % of the events in the radio-loud category (with DH radio bursts) are from the western hemisphere and the remaining 35 % are from the eastern hemisphere. On the other hand, in the radio-quiet category (without DH radio bursts), nearly 60 % of the events are from the eastern hemisphere in contrast to those of the radio-loud category. It is found that 81 % of the events from eastern regions have flare durations > 30 min in the DH-flare category, in contrast to a nearly equal number from the western side for flare durations longer/shorter than 30 min. Similarly, the eastern events in the DH-flare category have a longer average rise-time of

  1. How do type II topoisomerases use ATP hydrolysis to simplify DNA topology beyond equilibrium? Investigating the relaxation reaction of non-supercoiling type II topoisomerases

    PubMed Central

    Stuchinskaya, Tanya; Mitchenall, Lesley A.; Schoeffler, Allyn J.; Corbett, Kevin D.; Berger, James M.; Bates, Andrew D.; Maxwell, Anthony

    2015-01-01

    DNA topoisomerases control the topology of DNA (e.g. the level of supercoiling) in all cells. Type IIA topoisomerases are ATP-dependent enzymes that have been shown to simplify the topology of their DNA substrates to a level beyond that expected at equilibrium (i.e. more relaxed than the product of relaxation by ATP-independent enzymes, such as type I topoisomerases, or a lower than equilibrium level of catenation). The mechanism of this effect is currently unknown, although several models have been suggested. We have analysed the DNA relaxation reactions of type II topoisomerases to further explore this phenomenon. We find that all type IIA topoisomerases tested exhibit the effect to a similar degree and that it is not dependent on the C-terminal domains of the enzymes. As recently reported, the type IIB topoisomerase, topo VI (which is only distantly related to the type IIA enzymes), does not exhibit topology simplification. We find that topology simplification is not significantly dependent on circle size in the range ~2–9 kbp, and is not altered by reducing the free energy available from ATP hydrolysis by varying the ATP:ADP ratio. A direct test of one model (DNA tracking, i.e. sliding of a protein clamp along DNA to trap supercoils) suggests that this is unlikely to be the explanation for the effect. We conclude that geometric selection of DNA segments by the enzymes is likely to be a primary source of the effect but that it is possible that other factors contribute. We also speculate whether topology simplification might simply be an evolutionary relic, with no adaptive significance. PMID:19094994

  2. How do type II topoisomerases use ATP hydrolysis to simplify DNA topology beyond equilibrium? Investigating the relaxation reaction of nonsupercoiling type II topoisomerases.

    PubMed

    Stuchinskaya, Tanya; Mitchenall, Lesley A; Schoeffler, Allyn J; Corbett, Kevin D; Berger, James M; Bates, Andrew D; Maxwell, Anthony

    2009-02-06

    DNA topoisomerases control the topology of DNA (e.g., the level of supercoiling) in all cells. Type IIA topoisomerases are ATP-dependent enzymes that have been shown to simplify the topology of their DNA substrates to a level beyond that expected at equilibrium (i.e., more relaxed than the product of relaxation by ATP-independent enzymes, such as type I topoisomerases, or a lower-than-equilibrium level of catenation). The mechanism of this effect is currently unknown, although several models have been suggested. We have analyzed the DNA relaxation reactions of type II topoisomerases to further explore this phenomenon. We find that all type IIA topoisomerases tested exhibit the effect to a similar degree and that it is not dependent on the supercoil-sensing C-terminal domains of the enzymes. As recently reported, the type IIB topoisomerase, topoisomerase VI (which is only distantly related to type IIA enzymes), does not exhibit topology simplification. We find that topology simplification is not significantly dependent on circle size in the range approximately 2-9 kbp and is not altered by reducing the free energy available from ATP hydrolysis by varying the ADP:ATP ratio. A direct test of one model (DNA tracking; i.e., sliding of a protein clamp along DNA to trap supercoils) suggests that this is unlikely to be the explanation for the effect. We conclude that geometric selection of DNA segments by the enzymes is likely to be a primary source of the effect, but that it is possible that other kinetic factors contribute. We also speculate whether topology simplification might simply be an evolutionary relic, with no adaptive significance.

  3. Differentiation-inducing and anti-proliferative activities of isoliquiritigenin and all-trans-retinoic acid on B16F0 melanoma cells: Mechanisms profiling by RNA-seq.

    PubMed

    Chen, Xiaoyu; Yang, Ming; Hao, Wenjin; Han, Jichun; Ma, Jun; Wang, Caixia; Sun, Shiguo; Zheng, Qiusheng

    2016-10-30

    Melanoma is a cancer that arises from melanocytes, specialized pigmented cells that are found predominantly in the skin. The incidence of malignant melanoma has significantly increased over the last decade. With the development of therapy, the survival rate of some kind of cancer has been improved greatly. But the treatment of melanoma remains unsatisfactory. Much of melanoma's resistance to traditional chemotherapy is believed to arise intrinsically, by virtue of potent growth and cell survival-promoting genetic alteration. Therefore, significant attention has recently been focused on differentiation therapy, as well as differentiation inducer compounds. In previous study, we found isoliquiritigenin (ISL), a natural product extracted from licorice, could induce B16F0 melanoma cell differentiation. Here we investigated the transcriptional response of melanoma differentiation process induced by ISL and all-trans-retinoic acid (RA). Results showed that 390 genes involves in 201 biochemical pathways were differentially expressed in ISL treatment and 304 genes in 193 pathways in RA treatment. Differential expressed genes (DGEs, fold-change (FC)≥10) with the function of anti-proliferative and differentiation inducing indicated a loss of grade malignancy characteristic. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis indicated glutathione metabolism, glycolysis/gluconeogenesis and pentose phosphate pathway were the top three relative pathway perturbed by ISL, and mitogen-activated protein kinase (MAPK) signaling pathway was the most important pathway in RA treatment. In the analysis of hierarchical clustering of DEGs, we discovered 72 DEGs involved in the process of drug action. We thought Cited1, Tgm2, Xaf1, Cd59a, Fbxo2, Adh7 may have critical role in the differentiation of melanoma. The evidence displayed herein confirms the critical role of reactive oxygen species (ROS) in melanoma pathobiology and provides evidence for future targets in the

  4. Synthesis, spectral characterization, structural investigation and antimicrobial studies of mononuclear Cu(II), Ni(II), Co(II), Zn(II) and Cd(II) complexes of a new potentially hexadentate N2O4 Schiff base ligand derived from salicylaldehyde

    NASA Astrophysics Data System (ADS)

    Keypour, Hassan; Shayesteh, Maryam; Rezaeivala, Majid; Chalabian, Firoozeh; Elerman, Yalcin; Buyukgungor, Orhan

    2013-01-01

    A new potentially hexadentate N2O4 Schiff base ligand, H2L derived from condensation reaction of an aromatic diamine and salicylaldehyde, and its metal complexes were characterized by elemental analyses, IR, UV-Vis, EI-MS, 1H and 13C NMR spectra, as well as conductance measurements. It has been originated that the Schiff base ligand with Cu(II), Ni(II), Co(II), Cd(II) and Zn(II) ions form mononuclear complexes on 1:1 (metal:ligand) stoichiometry. The conductivity data confirm the non-electrolytic nature of the complexes. Also the crystal structures of the complexes [ZnL] and [CoL] have also been determined by using X-ray crystallographic technique. The Zn(II) and Co(II) complexes show a tetrahedral configuration. Electronic absorption spectra of the Cu(II) and Ni(II) complexes suggest a square-planar geometry around the central metal ion. The synthesized compounds have antibacterial activity against the three Gram-positive bacteria: Bacillus cereus, Enterococcus faecalis and Listeria monocytogenes and also against the three Gram-negative bacteria: Salmonella paraB, Citrobacter freundii and Enterobacter aerogenes. The results showed that in some cases the antibacterial activity of complexes were more than nalidixic acid and amoxicillin as standards.

  5. Detecting proton flux across chromatophores driven by F0F1-ATPase using N-(fluorescein-5-thiocarbamoyl)-1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine, triethylammonium salt.

    PubMed

    Yuanbo, Cui; Fan, Zhang; Jiachang, Yue

    2005-09-01

    N-(Fluorescein-5-thiocarbamoyl)-1,2-dihexadecanoyl-sn-glycero-3-phosphoethanolamine, triethylammonium salt (F-DHPE) is a lipid fluorescence dye sensitive to pH changes and is used in this study for detecting proton flux through F0F1-ATPase within chromatophores driven by ATP hydrolysis. F-DHPE is easily labeled to the outer surface of chromatophores. In the range of pH 7.0 to 9.0, fluorescence intensity is sensitive to pH changes. The sensitivity is especially great in the range of pH 8.2 to 9.0, so pH 8.6 was chosen as the appropriate experimental condition. It is shown that added ATP not only acts as a fluorescence quencher but also can be hydrolyzed by F0F1-ATPase to pump protons into chromatophores, resulting in fluorescence restoration. A stimulator (NaSO3) and various types of inhibitors (NaN3, 5'-adenylyl imidodiphosphate [AMP-PNP], and N,N'-dicyclohexylcarbodiimide [DCCD]) of F0F1 confirmed that fluorescence restoration is caused by ATP-driven proton flux. When loaded with one antibody (anti-beta antibody) or two antibodies (anti-beta antibody and sheep to rabbit second antibody), F0F1-ATPase exhibits lower proton pumping activities, as indicated by fluorescence restoration. The possible mechanism of the inhibition of antibodies on proton pumping activity is discussed.

  6. Investigation of interaction between the Pt(II) ions and aminosilane-modified silica surface in heterogeneous system

    NASA Astrophysics Data System (ADS)

    Nowicki, Waldemar; Gąsowska, Anna; Kirszensztejn, Piotr

    2016-05-01

    UV-vis spectroscopy measurements confirmed the reaction in heterogeneous system between Pt(II) ions and ethylenediamine type ligand, n-(2-aminoethyl)-3-aminopropyl-trimethoxysilane, immobilized at the silica surface. The formation of complexes is a consequence of interaction between the amine groups from the ligand grafted onto SiO2 and ions of platinum. A potentiometric titration technique was to determine the stability constants of complexes of Pt(II) with immobilized insoluble ligand (SG-L), on the silica gel. The results show the formation of three surface complexes of the same type (PtHSG-L, Pt(HSG-L)2, PtSG-L) with SG-L ligand, in a wide range of pH for different Debye length. The concentration distribution of the complexes in a heterogeneous system is evaluated.

  7. MX Siting Investigation. Geotechnical Evaluation of Luke Bombing and Gunnery Range. Geotechnical Report, Lechuguilla Desert, Arizona. Volume II. Appendix A.

    DTIC Science & Technology

    1978-01-20

    2100-2190 mn sec) T256m) 9100 ft see (2960 mn’sec) 13000-f 4800 ft ’sec (3960-4510 mn sec) S00 18000 8000 20000 22000 Saco __ __ BODO __ __ __ SPREAD AA...on the depth scale. 6000 22000 24000 26000 1000 eoo K L LOCATION MAP 36 ______ 10 380 0 36:500,36 30 10 20 0 1002 NAUTICAL, 00E 0 10 20 NI LOll E AS...gi 4900 144 ?.;Co 701 7 tAT4 400 - iSO I17 -17 Qo C 2A 1 7 lp s 17 1AQ4 TT Wi *1* * a. * * hI *t **,#l A eli *1* it~ a.** * hl il h,),i * * ii i ii, a

  8. A dual nitrite isotopic investigation of chemodenitrification by mineral-associated Fe(II) and its production of nitrous oxide

    NASA Astrophysics Data System (ADS)

    Grabb, Kalina C.; Buchwald, Carolyn; Hansel, Colleen M.; Wankel, Scott D.

    2017-01-01

    Under anaerobic conditions, the environmental reduction of nitrate (NO3-) and nitrite (NO2-) to more reduced forms is widely regarded as being microbially catalyzed. However, the chemical reduction of oxidized nitrogen species by reduced iron (Fe(II)), whether mineral-bound or surface-associated, may also occur under environmentally relevant conditions. Here we examine the nitrogen (N) and oxygen (O) stable isotope dynamics of the chemical reduction of NO2- by mineral associated Fe(II) (chemodenitrification) and its production of the potent greenhouse gas nitrous oxide (N2O). By shedding light on factors controlling kinetics of the reaction and its corresponding dual isotopic expression in the reactant NO2- and product N2O, this work contributes to a growing body of work aiming to improve our ability to identify chemodenitrification in the environment. Consistent with previous studies, we find that while homogenous reactions between aqueous NO2- and Fe(II) were kinetically slow, heterogeneous reactions involving Fe(II)-containing minerals often catalyzed considerable nitrite loss. In particular, rapid reduction of NO2- was catalyzed by the Fe-rich smectite clay mineral nontronite as well as the mixed Fe(II)-Fe(III) oxyhydroxide phase green rust. These minerals serve as both a source of reduced iron within the mineral structure as well as a surface for promoting the reactivity of Fe(II). However, even in the presence of aqueous Fe(II), experiments with low-Fe and non-Fe containing minerals showed little to no NO2- loss, perhaps suggesting a more dominant role for structural iron during chemodenitrification. When catalyzed by nontronite and green rust, N and O isotope effects for chemodenitrification (15εcDNF and 18εcDNF) ranged from 2 to 11‰ and 4 to 10‰, respectively, with lower values generally observed at higher reaction rates. Higher reaction rates were also linked to higher molar yields of N2O (up to 31%), highlighting a strong potential for

  9. Complex formation of Sn(II) with L-cysteine: an IR, DTA/TGA and DFT investigation.

    PubMed

    Novikova, Galina V; Petrov, Alexander I; Staloverova, Natalya A; Shubin, Alexander A; Dergachev, Ilya D

    2014-03-25

    The novel complex of Sn(II) with L-cysteine (L-H2Cys) has been synthesized and characterized by elemental analysis, TGA and IR spectroscopy. Vibrational assignment and DFT/PBE0/def2-TZVP ab initio simulation give evidence of cysteine molecule being coordinated to Sn(II) as three-dentate chelating N,O,S-donor ligand. The four Perdew density functionals TPSS, PBE0, PBE, TPSSh have been tested to provide consistency of simulated and experimental IR spectra, the best result is provided by unweighted Hartree-Fock density functionals (PBE, TPSS). On the contrary, the Hartree-Fock weighted functionals (PBE0, TPPSh) provide the most accurate geometry optimization. Unharmonic frequencies are obtained via ab initio vibrational self-consistent field (PT2-VSCF) calculations at DFT/TPSS/Def2-TZVP level, the vibrational assignment of IR spectra has been carried out. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Single-crystal EPR investigation of Mn(II)-doped biomineral cobalt ammonium phosphate hexahydrate: a case of multiple substitutions

    NASA Astrophysics Data System (ADS)

    Deepa, S.; Natarajan, B.; Mithira, S.; Velavan, K.; Rao, P. S.

    2005-08-01

    Single-crystal electron paramagnetic resonance (EPR) study of Mn(II)-doped cobalt ammonium phosphate hexahydrate has been carried out at room temperature. The impurity shows more than 30 line pattern EPR spectra along the three crystallographic axes, suggesting the existence of more than one type of impurity ion in the host lattice. The spin Hamiltonian parameters, estimated from the three mutually orthogonal crystal rotations, are: site 1: g(xx) =1.989, g(yy) =1.994, g(zz) =1.999, A(xx) =-8.97, A(yy) =-9.52, A(zz) =-9.71 mT, D-xx =-8.09 mT, D-yy =-6.05 mT, D-zz =14.14 mT, site 2: g(xx) =1.988, g(yy) =2.009, g(zz) =2.019, A(xx) =-9.11 mT, A(yy) =-9.58 mT, A(zz) =-9.93 mT, D-xx =-6.61 mT, D-yy =-6.11 mT, D-zz =12.72 mT. The angular variation studies further reveal that the Mn(II) impurities enter the lattice substitutionally. The other Mn(II) sites which are at interstitial locations are difficult to follow due to their low intensity. The variation of zero-field splitting parameter with temperature indicates no phase transition. The observation of well-resolved Mn(II) spectrum at room temperature has been interpreted in terms of 'host spin-lattice relaxation narrowing mechanism.

  11. Vibrational investigation on the copper(II) binding mode of carcinine and its pH dependence

    NASA Astrophysics Data System (ADS)

    Torreggiani, Armida; Reggiani, Matteo; Manco, Immacolata; Tinti, Anna

    2007-05-01

    A comparative FT-Raman and FT-IR study of Carcinine (Carc), a natural imidazole dipeptide, and its complexes with Cu(II) ions was performed at different pH's. Both Raman and IR spectra present marker bands useful for the identification of the predominant complexes; in particular, Raman spectroscopy appears useful for identifying the metal-coordination site of the imidazole ring (N π or N τ atoms) of Carc. Free Carc shows a strong network of H-bonds and tautomer I (N τ-H) is the preferred form of the imidazolic ring (bands at 1578, 1292 and 988 cm -1). The presence of Cu(II) does not affect the tautomeric equilibrium at pH 7, whereas the deprotonation of both N-imidazolic nitrogens is strongly induced at higher pH. Under neutral and alkaline conditions the primary amino group takes part to the Cu(II) chelation, whereas all the peptidic moieties are involved in coordination only at pH 7. Thus, Carc acts as a tri-dentate ligand at neutral pH, mainly giving a monomeric complex, [CuLH -1], containing tautomer I, whereas an oligonuclear complex, probably [Cu 4L 4H -8], where metal-imidazolate ions connect different ligand molecules, predominates at alkaline pH.

  12. Altitude-Wind-Tunnel Investigation of a 4000-Pound-Thrust Axial-Flow Turbojet Engine. II - Operational Characteristics. II; Operational Characteristics

    NASA Technical Reports Server (NTRS)

    Fleming, William A.

    1948-01-01

    An investigation was conducted in the Cleveland altitude wind tunnel to determine the operational characteristics of an axial flow-type turbojet engine with a 4000-pound-thrust rating over a range of pressure altitudes from 5,000 to 50,OOO feet, ram pressure ratios from 1.00 to 1.86, and temperatures from 60 deg to -50 deg F. The low-flow (standard) compressor with which the engine was originally equipped was replaced by a high-flow compressor for part of the investigation. The effects of altitude and airspeed on such operating characteristics as operating range, stability of combustion, acceleration, starting, operation of fuel-control systems, and bearing cooling were investigated. With the low-flow compressor, the engine could be operated at full speed without serious burner unbalance at altitudes up to 50,000 feet. Increasing the altitude and airspeed greatly reduced the operable speed range of the engine by raising the minimum operating speed of the engine. In several runs with the high-flow compressor the maximum engine speed was limited to less than 7600 rpm by combustion blow-out, high tail-pipe temperatures, and compressor stall. Acceleration of the engine was relatively slow and the time required for acceleration increased with altitude. At maximum engine speed a sudden reduction in jet-nozzle area resulted in an immediate increase in thrust. The engine started normally and easily below 20,000 feet with each configuration. The use of a high-voltage ignition system made possible starts at a pressure altitude of 40,000 feet; but on these starts the tail-pipe temperatures were very high, a great deal of fuel burned in and behind the tail-pipe, and acceleration was very slow. Operation of the engine was similar with both fuel regulators except that the modified fuel regulator restricted the fuel flow in such a manner that the acceleration above 6000 rpm was very slow. The bearings did not cool properly at high altitudes and high engine speeds with a low

  13. $B^{0}_{s}$ Lifetime Measurement in the CP-odd Decay Channel $B^{0}_{s} \\to J/\\psi\\mbox{ }f_{0}(980)$

    SciTech Connect

    Abazov, V. M.

    2016-07-06

    Here, the lifetime of the Bs0 meson is measured in the decay channel Bs0→J/ψπ+π- with 880 ≤ Mπ+π- ≤ 1080 MeV/c2, which is mainly a CP-odd state and dominated by the f0(980) resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the Bs0 meson is measured to be τ(Bs0) = 1.70 ± 0.14(stat) ± 0.05(syst) ps. Neglecting CP violation in Bs0/$\\bar{B}$0s mixing, the measurement can be translated into the width of the heavy mass eigenstate of the Bs0, ΓH = 0.59 ± 0.05(stat) ± 0.02(syst) ps-1.

  14. $B^{0}_{s}$ Lifetime Measurement in the CP-odd Decay Channel $B^{0}_{s} \\to J/\\psi\\mbox{ }f_{0}(980)$

    SciTech Connect

    Abazov, V. M.

    2016-07-06

    Here, the lifetime of the Bs0 meson is measured in the decay channel Bs0→J/ψπ+π- with 880 ≤ Mπ+π- ≤ 1080 MeV/c2, which is mainly a CP-odd state and dominated by the f0(980) resonance. In 10.4 fb-1 of data collected with the D0 detector in Run II of the Tevatron, the lifetime of the Bs0 meson is measured to be τ(Bs0) = 1.70 ± 0.14(stat) ± 0.05(syst) ps. Neglecting CP violation in Bs0/$\\bar{B}$0s mixing, the measurement can be translated into the width of the heavy mass eigenstate of the Bs0, ΓH = 0.59 ± 0.05(stat) ± 0.02(syst) ps-1.

  15. Validated quantitation of angiotensin II receptor antagonists (ARA-II) in human plasma by liquid-chromatography-tandem mass spectrometry using minimum sample clean-up and investigation of ion suppression.

    PubMed

    Ferreirós, Nerea; Dresen, Sebastian; Alonso, Rosa María; Weinmann, Wolfgang

    2007-12-01

    For the quantitation of angiotensin II receptor antagonists (ARA-II) in human plasma, a method using liquid-chromatography (LC)-electrospray ionization tandem mass spectrometry (MS/MS) has been developed with respect to simple sample clean-up and investigation of ion suppression effects. For sample preparation, protein precipitation using zinc sulphate and methanol showed advantages in speed, recovery, and reproducibility over solid-phase extraction. A triple quadrupole mass spectrometer (Sciex API 365) with turbo ionspray source was used for detection of compounds with multireaction monitoring (MRM) of two transitions per compound. Suppression effects caused by endogenous matrix compounds were investigated by post-column infusion of analytes and LC analysis of precipitates of blank plasma samples and could be excluded. A validation was performed for the ARA-II drugs (valsartan, irbesartan, losartan and its active metabolite EXP 3174, eprosartan, candesartan, and telmisartan). The developed method showed good intra- and interday precision (<12% relative standard deviation) and accuracy (<11.5% bias) at different concentrations for all the studied compounds. The calculated lower limits of quantitation were between 7 and 13 ng/mL, and the compounds were stable during the analytical process. These rather expensive drugs against hypertension are prescribed with increasing numbers in Europe and the industrialized nations. Complications might arise from overdosage or metabolic disorders. However, drug monitoring is not usually performed. Because the therapeutic concentrations range from a few nanograms to hundreds of nanograms per milliliter for the different drugs, and they are not amenable to gas chromatography/MS analysis because of their high molecular weight and polarity, the LC-MS/MS method is the golden standard for therapeutic drug monitoring and for clinical and forensic toxicology of ARA-II drugs.

  16. DFT investigations of the reaction mechanism of diethyl carbonate synthesis catalyzed by Cu(I)/β or Pd(II)/β zeolites

    NASA Astrophysics Data System (ADS)

    Shen, Yongli; Wang, Shengping; Huang, Shouying; Li, Zhong; Ma, Xinbin

    2014-07-01

    Density functional theory (DFT) calculations are used to investigate the oxidative carbonylation of ethanol occurring on Cu(I)/β or Pd(II)/β. The thermochemistry and activation energy for all elementary steps involved in the formation of diethyl carbonate are presented. Upon calculation, we identify that the mechanisms for the formation of surface O atom are varying on different catalysts. Ethanol can react with the surface O atom to produce (C2H5O)(OH)-M/β (M = Cu+, Pd2+) species. And this intermediate can further react with carbon monoxide or ethanol to give monoethyl carbonate or di-ethoxied species ((C2H5O)2-M/β). Diethyl carbonate can form via two distinct reaction pathways: (I) ethanol reacts with monoethyl carbonate or (II) carbon monoxide inserts into di-ethoxide species. Upon calculation, we confirmed that both reaction pathways for the formation of DEC are accessible on Cu(I)/β catalyst, whereas only Path II is achievable on Pd(II)/β catalyst.

  17. Investigation of the maximum quantum yield of PS II in Haematococcus pluvialis cell cultures during growth: effects of chemical or high-intensity light treatment.

    PubMed

    Wang, Hui-Chih; Cho, Man-Gi; Riznichenko, Galina; Rubin, Andrey B; Lee, Ji-Hyun

    2011-09-02

    In this study, we investigated the increase in photosynthetic quantum yield that occurs in advance of increased microalgal growth. Haematococcus pluvialis was cultivated under normal conditions; the number of cells, the maximum quantum yield of photosystem II (F(v)/F(m)), and optical density were measured. We observed an increase in F(v)/F(m) approximately 72h prior to the cell growth phase. To confirm the relationship between photosynthetic yield and growth, samples were treated with several chemicals under high-intensity light illumination and control conditions to inhibit photosystem II and induce a decrease in the quantum photosynthetic yield. The samples were exposed to high-intensity light at an irradiance of 400μmol photonsm(-2)s(-1) for varied amount of time and were treated with chemicals such as 3-(3,4-dichlorophenyl)-1,1-dimethylurea, nigericin sodium salt and valinomycin. We observed that both the photooxidation of photosystem II reaction centers and the formation of transmembrane electrochemical gradients led to an initial decrease in fluorescence yield after the onset of high-intensity light illumination. We also observed that treatment of high-intensity light illuminated cells with antibiotics after adaptation to moderate light intensities caused a difference in photosynthetic activity. In conclusion, the maximum quantum yield of photosystem II is obtained prior to the cell growth phase and can therefore be used as a prediction parameter for cell growth. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. The design of phase II clinical trials testing cancer therapeutics: consensus recommendations from the clinical trial design task force of the national cancer institute investigational drug steering committee.

    PubMed

    Seymour, Lesley; Ivy, S Percy; Sargent, Daniel; Spriggs, David; Baker, Laurence; Rubinstein, Larry; Ratain, Mark J; Le Blanc, Michael; Stewart, David; Crowley, John; Groshen, Susan; Humphrey, Jeffrey S; West, Pamela; Berry, Donald

    2010-03-15

    The optimal design of phase II studies continues to be the subject of vigorous debate, especially studies of newer molecularly targeted agents. The observations that many new therapeutics "fail" in definitive phase III studies, coupled with the numbers of new agents to be tested as well as the increasing costs and complexity of clinical trials, further emphasize the critical importance of robust and efficient phase II design. The Clinical Trial Design Task Force (CTD-TF) of the National Cancer Institute (NCI) Investigational Drug Steering Committee (IDSC) has published a series of discussion papers on phase II trial design in Clinical Cancer Research. The IDSC has developed formal recommendations about aspects of phase II trial design that are the subject of frequent debate, such as endpoints (response versus progression-free survival), randomization (single-arm designs versus randomization), inclusion of biomarkers, biomarker-based patient enrichment strategies, and statistical design (e.g., two-stage designs versus multiple-group adaptive designs). Although these recommendations in general encourage the use of progression-free survival as the primary endpoint, randomization, inclusion of biomarkers, and incorporation of newer designs, we acknowledge that objective response as an endpoint and single-arm designs remain relevant in certain situations. The design of any clinical trial should always be carefully evaluated and justified based on characteristic specific to the situation.

  19. Chemical and cellular investigations of trans-ammine-pyridine-dichlorido-platinum(II), the likely metabolite of the antitumor active cis-diammine-pyridine-chorido-platinum(II).

    PubMed

    Xu, Dechen; Min, Yuanzeng; Cheng, Qinqin; Shi, Hongdong; Wei, Kaiju; Arnesano, Fabio; Natile, Giovanni; Liu, Yangzhong

    2013-12-01

    It has been proposed that the well-studied monofunctional platinum complex cis-[PtCl(NH3)2(py)](+) (cDPCP) forms DNA adducts similar to those of the trans platinum complex trans-[PtCl2(NH3)(py)] (ampyplatin, py=pyridine). Thus this latter could be the active form of cDPCP. Detailed studies on the mechanism of ampyplatin action were performed in this work. Results indicate that ampyplatin has significantly higher antiproliferative activity than cDPCP and is comparable to cisplatin. Cellular uptake experiments indicate that ampyplatin can be efficiently accumulated in A549 cancer cells. Binding of ampyplatin to DNA mainly produces monofunctional adducts; remarkably, these adducts can be recognized by the HMGB1 protein. Kinetic studies on the reaction with GMP indicate that the reactivity of ampyplatin is much lower than that of transplatin and is more similar to that of trans-[PtCl2{E-HN=C(Me)OMe}2] (trans-EE), a widely investigated antitumor active trans-oriented platinum complex. In addition, the hydrolysis of ampyplatin is significantly suppressed, whereas the hydrolysis of the mono-GMP adduct is highly enhanced. These results indicate that the mechanism of ampyplatin differs not only from that of antitumor inactive transplatin but also from that of antitumor active trans-EE and this could account for the remarkable activity of parent cDPCP.

  20. Measurements of branching fractions, polarizations, and direct CP-violation asymmetries in B -> rho0 K* and B -> f0(980) K* decays

    SciTech Connect

    del Amo Sanchez, P.; Lees, J.P.; Poireau, V.; Prencipe, E.; Tisserand, V.; Garra Tico, J.; Grauges, E.; Martinelli, M.; Milanes, D.A.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Brown, D.N.; Kerth, L.T.; Kolomensky, Yu.G.; Lynch, G.; Osipenkov, I.L.; Koch, H.; Schroeder, T.; /Ruhr U., Bochum /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UC, Riverside /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Dresden, Tech. U. /Ecole Polytechnique /Edinburgh U. /INFN, Ferrara /Ferrara U. /INFN, Ferrara /INFN, Ferrara /Ferrara U. /INFN, Ferrara /Frascati /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /INFN, Genoa /INFN, Genoa /Genoa U. /Indian Inst. Tech., Guwahati /Harvard U. /Harvey Mudd Coll. /Heidelberg U. /Humboldt U., Berlin /Imperial Coll., London /Iowa State U. /Iowa State U. /Johns Hopkins U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Mainz U., Inst. Kernphys. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT /McGill U. /INFN, Milan /Milan U. /INFN, Milan /INFN, Milan /Milan U. /Mississippi U. /Montreal U. /INFN, Naples /Naples U. /NIKHEF, Amsterdam /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /INFN, Padua /Padua U. /INFN, Padua /INFN, Padua /Padua U. /Paris U., VI-VII /INFN, Perugia /Perugia U. /INFN, Pisa /Pisa U. /INFN, Pisa /Pisa, Scuola Normale Superiore /INFN, Pisa /Pisa U. /INFN, Pisa /Princeton U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /INFN, Rome /INFN, Rome /Rome U. /Rostock U. /Rutherford /DAPNIA, Saclay /SLAC /South Carolina U. /Southern Methodist U. /Stanford U., Phys. Dept. /SUNY, Albany /Tel Aviv U. /Tennessee U. /Texas Nuclear Corp., Austin /Texas U., Dallas /INFN, Turin /Turin U. /INFN, Trieste /Trieste U. /Valencia U. /Victoria U. /Warwick U. /Wisconsin U., Madison

    2011-08-12

    We present measurements of the branching fractions, longitudinal polarization, and direct CP-violation asymmetries for the decays B{sup +} {yields} {rho}{sup 0}K*{sup +} and B{sup +} f{sub 0}(980)K*{sup +} with a sample of (467 {+-} 5) x 10{sup 6} B{bar B} pairs collected with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the SLAC National Accelerator Laboratory. We observe B{sup +} {yields} {rho}{sup 0}K*{sup +} with a significance of 5.3{sigma} and measure the branching fraction {Beta}(B{sup +} {yields} {rho}{sup 0}K*{sup +}) = (4.6 {+-} 1.0 {+-} 0.4) x 10{sup -6}, the longitudinal polarization f{sub L} = 0.78 {+-} 0.12 {+-} 0.03, and the CP-violation asymmetry A{sub CP} = 0.31 {+-} 0.13 {+-} 0.03. We observe B{sup +} {yields} f{sub 0}(980)K*{sup +} and measure the branching fraction {Beta}(B{sup +} {yields} f{sub 0}(980)K*{sup +}) x {Beta}(f{sub 0}(980) {yields} {pi}{sup +}{pi}{sup -}) = (4.2 {+-} 0.6 {+-} 0.3) x 10{sup -6} and the CP-violation asymmetry A{sub CP} = -0.15 {+-} 0.12 {+-} 0.03. The first uncertainty quoted is statistical and the second is systematic.

  1. Effects of maturase binding and Mg2+ concentration on group II intron RNA folding investigated by UV cross-linking.

    PubMed

    Noah, James W; Lambowitz, Alan M

    2003-11-04

    The Lactococcus lactis Ll.LtrB group II intron encodes a reverse transcriptase/maturase (LtrA protein) that promotes RNA splicing by stabilizing the catalytically active RNA structure. Here, we mapped 17 UV cross-links induced in both wild-type Ll.LtrB RNA and Ll.LtrB-Delta2486 RNA, which has a branch-point deletion that prevents splicing, and we used these cross-links to follow tertiary structure formation under different conditions in the presence or absence of the LtrA protein. Twelve of the cross-links are long-range, with six near known tertiary interaction sites in the active RNA structure. In a reaction medium containing 0.5 M NH(4)Cl, eight of the 17 cross-links were detected in the absence of Mg(2+) or the presence of EDTA, and all were detected at 5 mM Mg(2+), where efficient splicing requires the LtrA protein. The frequencies of all but four cross-links increased with increasing Mg(2+) concentrations, becoming maximal between 4 and 50 mM Mg(2+), where the intron is self-splicing. These findings suggest that a high Mg(2+) concentration induces self-splicing by globally stabilizing tertiary structure, including key tertiary interactions that are required for catalytic activity. Significantly, the binding of the maturase under protein-dependent splicing conditions (0.5 M NH(4)Cl and 5 mM Mg(2+)) increased the frequency of only nine cross-links, seven of which are long-range, suggesting that, in contrast to a high Mg(2+) concentration, LtrA promotes splicing by stabilizing critical tertiary structure interactions, while leaving other regions of the intron relatively flexible. This difference may contribute to the high rate of protein-dependent splicing, relative to the rate of self-splicing. The propensity of the intron RNA to form tertiary structure even at relatively low Mg(2+) concentrations raises the possibility that the maturase functions at least in part by tertiary structure capture. Finally, an abundant central wheel cross-link, present in >50% of

  2. Investigation of easy-plane magnetic anisotropy in P-ligand square-pyramidal Co(II) single ion magnets.

    PubMed

    Mondal, Amit Kumar; Jover, Jesús; Ruiz, Eliseo; Konar, Sanjit

    2017-05-09

    In this work we report two pentacoordinated Co(II)-P4X1 Single Ion Magnets (SIMs) based on P-donor ligands. The tetradentate ligand tris[2-(diphenylphosphino)ethyl]phosphine allows the obtention of the isostructural square pyramidal [Co(PP3)Cl]·ClO4 (1) and [Co(PP3)Br]·ClO4 (2) complexes. Consistent theoretical and experimental studies indicate that these complexes have a high spin (S = 3/2) ground state and suggest that the relaxation dynamics is governed by ground state quantum tunneling, whereas its temperature dependence is directed by optical or acoustic Raman processes.

  3. Effects of PEGylated lipid nanoparticles on the oral absorption of one BCS II drug: a mechanistic investigation.

    PubMed

    Zhang, Xingwang; Chen, Guijiang; Zhang, Tianpeng; Ma, Zhiguo; Wu, Baojian

    2014-01-01

    Lipid nanocarriers are becoming a versatile platform for oral delivery of lipophilic drugs. In this article, we aimed to explore the gastrointestinal behaviors of lipid nanoparticles and the effect of PEGylation on oral absorption of fenofibrate (FN), a Biopharmaceutics Classification System (BCS) II model drug. FN-loaded PEGylated lipid nanoparticles (FN-PLNs) were prepared by the solvent-diffusion method and characterized by particle size distribution, morphology, Fourier transform infrared spectroscopy, and drug release. Lipolytic experiments were performed to assess the resistance of lipid nanoparticles against pancreatic lipase. Pharmacokinetics was evaluated in rats after oral administration of FN preparations. The obtained FN-PLNs were 186.7 nm in size with an entrapment efficiency of >95%. Compared to conventional lipid nanoparticles, PLNs exhibited slower drug release in the lipase-containing medium, strikingly reduced mucin binding, and suppressed lipolysis in vitro. Further, oral absorption of FN was significantly enhanced using PLNs with relative bioavailability of 123.9% and 157.0% to conventional lipid nanoparticles and a commercial formulation (Lipanthyl(®)), respectively. It was demonstrated that reduced mucin trapping, suppressed lipolysis, and/or improved mucosal permeability were responsible for increased oral absorption. These results facilitated a better understanding of the in vivo fate of lipid nanoparticles, and suggested the potential of PLNs as oral carriers of BCS II drugs.

  4. ATR-FTIR spectroscopic investigation of the cis- and trans-bis-(α-amino acids) copper(II) complexes

    NASA Astrophysics Data System (ADS)

    Berestova, Tatyana V.; Kuzina, Lyudmila G.; Amineva, Natalya A.; Faizrakhmanov, Ilshat S.; Massalimov, Ismail A.; Mustafin, Akhat G.

    2017-06-01

    The crystalline phases of the trans-(a) and cis-(b)-isomers of bis-(α-amino acids) copper(II) complexes [Cu(bL)2] 1-5 (bL - bidentate ligand: gly (1), S-ala (2), R,S-val (3), (±)-thr (4), R,S-phe (5)) were studied by ATR-FTIR spectroscopy in the mid region IR spectrum. It was established that asymmetric νas(COO) and symmetric νs(COO) stretching vibrations of carboxylic groups of 1-5 are sensitive to change of the geometric structure and have a different maxima for the trans(a)- and cis(b)-isomers. It found that νas(COO) and νs(COO) stretching vibrations of cis-isomers are broadened and shifted to longer wavelengths (b) as compared with trans-isomers (a). Shown that peculiarities of crystal packing molecules of geometric isomers may affect on carboxylate stretching vibration bis-α-amino acids complexes copper(II) 1-5 a,b.

  5. Theoretical investigation of hydrogen bonding between water and platinum(II): an atom in molecule (AIM) study

    NASA Astrophysics Data System (ADS)

    Li, Yan; Zhang, Guiqiu; Chen, Dezhan

    2012-02-01

    Recently, Rizzato et al. [Angew. Chem. Int. Ed. 49, 7440 (2010)] [1] reported a hydrogen-bonding-like interaction between a water molecule and a d8 metal ion (PtII) based on neutron diffraction, and provided the first crystallographic evidence for this interaction. We studied the hydrogen bonding of the O-H ... Pt interaction theoretically using atoms in molecule (AIM) and natural bond orbital analysis (NBO) in the crystallographic geometries. The method used density functional theory (DFT) with the hybrid B3LYP function. For platinum atoms, we used the Los Alamos National Laboratory 2-Double-Zeta (LANL2DZ) basis set, and for the other atoms we used 6-311++G(d,p) basis sets. Criteria based on a topological analysis of the electron density were used in order to characterize the nature of interactions in the complexes. The main purpose of the present work is to provide an answer to the following questions: Why can a filled d orbital of square-planar d8 metal ions such as platinum(II) also act as hydrogen-bond acceptors? Can a study based on the electron charge density answer this question? A good correlation between the density at the intermolecular bond critical point and the energy interaction was found. The interaction is mainly closed-shell and there is some charge transfer in this system.

  6. Effects of PEGylated lipid nanoparticles on the oral absorption of one BCS II drug: a mechanistic investigation

    PubMed Central

    Zhang, Xingwang; Chen, Guijiang; Zhang, Tianpeng; Ma, Zhiguo; Wu, Baojian

    2014-01-01

    Lipid nanocarriers are becoming a versatile platform for oral delivery of lipophilic drugs. In this article, we aimed to explore the gastrointestinal behaviors of lipid nanoparticles and the effect of PEGylation on oral absorption of fenofibrate (FN), a Biopharmaceutics Classification System (BCS) II model drug. FN-loaded PEGylated lipid nanoparticles (FN-PLNs) were prepared by the solvent-diffusion method and characterized by particle size distribution, morphology, Fourier transform infrared spectroscopy, and drug release. Lipolytic experiments were performed to assess the resistance of lipid nanoparticles against pancreatic lipase. Pharmacokinetics was evaluated in rats after oral administration of FN preparations. The obtained FN-PLNs were 186.7 nm in size with an entrapment efficiency of >95%. Compared to conventional lipid nanoparticles, PLNs exhibited slower drug release in the lipase-containing medium, strikingly reduced mucin binding, and suppressed lipolysis in vitro. Further, oral absorption of FN was significantly enhanced using PLNs with relative bioavailability of 123.9% and 157.0% to conventional lipid nanoparticles and a commercial formulation (Lipanthyl®), respectively. It was demonstrated that reduced mucin trapping, suppressed lipolysis, and/or improved mucosal permeability were responsible for increased oral absorption. These results facilitated a better understanding of the in vivo fate of lipid nanoparticles, and suggested the potential of PLNs as oral carriers of BCS II drugs. PMID:25473287

  7. A first principles investigation of electron transfer between Fe(II) and U(VI) on insulating Al- vs. semiconducting Fe-oxide surfaces via the proximity effect

    NASA Astrophysics Data System (ADS)

    Taylor, S. D.; Marcano, M. C.; Becker, U.

    2017-01-01

    This study investigates how the intrinsic chemical and electronic properties of mineral surfaces and their associated electron transfer (ET) pathways influence the reduction of U(VI) by surface-associated Fe(II). Density functional theory (DFT), including the Hubbard U correction to the exchange-correlation functional, was used to investigate sorption/redox reactions and ET mechanisms between Fe(II) and U(VI) coadsorbed on isostructural, periodic (0 0 1) surfaces of the insulator corundum (α-Al2O3) vs. the semiconductor hematite (α-Fe2O3). Furthermore, the coadsorbed Fe(II) and U(VI) ions are spatially separated from one another on the surfaces (⩾5.9 Å) to observe whether electronic-coupling through the semiconducting hematite surface facilitates ET between the adsorbates, a phenomenon known as the proximity effect. The calculations show that the different chemical and electronic properties between the isostructural corundum and hematite (0 0 1) surfaces lead to considerably different ET mechanisms between Fe(II) and U(VI). ET on the insulating corundum (0 0 1) surface is limited by the adsorbates' structural configuration. When Fe(II) and U(VI) are spatially separated and do not directly interact with one another (e.g. via an inner-sphere complex), U(VI) reduction by Fe(II) cannot occur as there is no physical pathway enabling ET between the adsorbates. In contrast to the insulating corundum (0 0 1) surface, the hematite (0 0 1) surface can potentially participate in ET reactions due to the high number of electron acceptor sites from the Fe d-states near the Fermi level at the hematite surface. The adsorption of Fe(II) also introduces d-states near the Fermi level as well as shifts unoccupied d-states of the Fe cations at the hematite surface to lower energies, making the surface more conductive. In turn, electronic coupling through the surface can link the spatially separated adsorbates to one another and provide distinct ET pathways for an electron from Fe(II

  8. Fracture Behavior Investigation of a Typical Sandstone Under Mixed-Mode I/II Loading Using the Notched Deep Beam Bending Method

    NASA Astrophysics Data System (ADS)

    Luo, Y.; Ren, L.; Xie, L. Z.; Ai, T.; He, B.

    2017-08-01

    The brittle fracture behavior of rocks under mixed-mode loading is important in rock engineering. First, a new configuration called the notched deep beam (NDB) specimen was introduced for the fracture testing of rock materials under mixed-mode I/II loading, and a series of finite element analyses were performed to calibrate the dimensionless fracture parameters (i.e., Y I, Y II and T^{*}). The results showed that an NDB specimen subjected to three-point bending is able to generate pure mode I loading, pure mode II loading, and any mixed-mode loading in between. Then, several NDB specimens made of sandstone were used to investigate the brittle fracture behavior of rock under mixed-mode I/II loading. The fracture surfaces were theoretically described using a statistical method, and the results indicated that all the fracture surfaces generated under different mixed-mode loading were statistically identical; to some extent, these results experimentally showed that only tensile fracture occurs under mixed-mode I/II loading. The obtained fracture strengths were then analyzed using several brittle fracture criteria. The empirical criterion, maximum energy release rate criterion, generalized maximum tangential stress (GMTS) criterion, and improved R-criterion accurately predicted the fracture strength envelope of the sandstone. Finally, based on the concepts of point stress and mean stress, the micro-crack zones (MCZs) under different mixed-mode loading were theoretically estimated based on the MTS and GMTS criteria. The critical radius of MCZ in the crack propagation direction was not a constant for all mixed-mode loading conditions regardless of whether the T-stress was considered. This result suggests that the size of the core region used to predict the crack initiation direction and fracture strength based on the GMTS criterion should be chosen more carefully.

  9. An investigation of climate patterns on Earth-like planets using the NASA GISS global climate model II

    NASA Astrophysics Data System (ADS)

    Elowitz, Robert Mark

    To determine the capability of NASA's GISS GCM-II global climate model, the user-friendly EdGCM interface to the 3-D climate model code was evaluated by simulating global climate patterns that Earth-like planets may experience. The simulation scenarios involved different greenhouse gas emissions trends, planetary orbital parameters, and solar irradiance variations. It is found that the EdGCM interface to the GCM-II 3-D climate model is capable of studying climate patterns on hypothetical Earth-like planets, with some limitations involved. Studying extreme climate patterns on Earth-like planets as a function of planetary obliquity, orbital eccentricity, atmospheric composition, solar irradiance variations, and location with the host star's habitable zone is needed to determine whether such planets are habitable for life as we know it. Studying the behavior of climate on hypothetical Earth-like planet also provides insight into the future climate of our own planet. A database of climate models based on hypothetical Earth-like worlds will provide a valuable resource to the astrobiology community in support of future detections of exoplanets with masses, sizes, and composition similar to Earth. At present, most studies involved the use of 1-D, or 2-D climate models to explore planetary climate on Earth-like planets. This is due to the difficulty of using very complex 3-D climate model codes that typically have poor user interfaces or interfaces that are very difficult to use. EdGCM provides scientists with a user-friendly interface to a full 3-D climate model capable of simulating the climate on Earth-like planets. However, EdGCM is extremely limited in studying global climate on exo-Earth planets outside our solar system. The user is able to change the simulation initial conditions, including different greenhouse gas concentrations and their associated trends, solar irradiance and its trend over time, planetary obliquity and orbit eccentricity, and heliocentric

  10. Air-Pollution and Cardiometabolic Diseases (AIRCMD): a prospective study investigating the impact of air pollution exposure and propensity for type II diabetes.

    PubMed

    Sun, Zhichao; Mukherjee, Bhramar; Brook, Robert D; Gatts, Geoffrey A; Yang, Fumo; Sun, Qinghua; Brook, Jeffrey R; Fan, Zhongjie; Rajagopalan, Sanjay

    2013-03-15

    There is a paucity of prospective cohort studies investigating the impact of environmental factors on the development of cardiometabolic (CM) disorders like type II diabetes (T2DM). The objective of the Air-Pollution and Cardiometabolic Diseases (AIRCMD) study is to investigate the impact of personal level air pollution measures [personal black carbon (BC)/sulfate measures] and ambient fine particulate matter [(PM2.5)/NO2] levels on propensity to type II diabetes in Beijing, China. Subjects with metabolic syndrome will undergo four repeated study visits within each season over a one year period following an initial screening visit. At each study visit, subjects will be monitored for sub-acute exposure to personal and ambient measures of air-pollution exposure and will undergo a series of functional CM outcomes. The primary endpoints include independent associations between integrated 5-day mean exposure to PM2.5 and BC and homeostasis model assessment of insulin resistance (HOMA-IR) measures, 24-hour mean diastolic and mean arterial pressure and endothelial-dependent vasodilatation. The secondary endpoints will explore the mechanistic explanation for a causal relationship between exposures and propensity for type II diabetes and will include additional functional outcomes such as arterial compliance, heart rate variability and plasma adipokines. The novel aspects of the study include the launch of infrastructure for future translational investigations in highly polluted urbanized environments and the creation of novel methodologies for linking personalized exposure measurements with functional CM outcomes. We believe that AIRCMD will allow for unprecedented new investigations into the association between environmental risk factors and CM disorders.

  11. Reactivity of dicoordinated stannylones (Sn0) versus stannylenes (SnII): an investigation using DFT-based reactivity indices.

    PubMed

    Broeckaert, Lies; Frenking, Gernot; Geerlings, Paul; De Proft, Frank

    2013-10-07

    The reactivity of dicoordinated Sn(0) compounds, stannylones, is probed using density functional theory (DFT)-based reactivity indices and compared with the reactivity of dicoordinated Sn(II) compounds, stannylenes. For the former compounds, the influence of different types of electron-donating ligands, such as cyclic and acyclic carbenes, stannylenes and phosphines, on the reactivity of the central Sn atom is analyzed in detail. Sn(0) compounds are found to be relatively soft systems with a high nucleophilicity, and the plots of the Fukui function f(-) for an electrophilic attack consistently predict the highest reactivity on the Sn atom. Next, complexes of dicoordinated Sn compounds with different Lewis acids of variable hardness are computed. In a first part, the double-base character of stannylones is demonstrated in interactions with the hardest Lewis acid H(+). Both the first and second proton affinities (PAs) are high and are well correlated with the atomic charge on the Sn atom, probing its local hardness. These observations are also in line with electrostatic potential plots that demonstrate that the tin atom in Sn(0) compounds bears a higher negative charge in comparison to Sn(II) compounds. Stannylones and stannylenes can be distinguished from each other by the partial charges at Sn and by various reactivity indices. It also becomes clear that there is a smooth transition between the two classes of compounds. We furthermore demonstrate both from DFT-based reactivity indices and from energy decomposition analysis, combined with natural orbitals for chemical valence (EDA-NOCV), that the monocomplexed stannylones are still nucleophilic and as reactive towards a second Lewis acid as towards the first one. The dominating interaction is a strong σ-type interaction from the Sn atom towards the Lewis acid. The interaction energy is higher for complexes with the cation Ag(+) than with the non-charged electrophiles BH(3), BF(3), and AlCl(3).

  12. DFT investigation of Ni(II) adsorption onto MA-DTPA/PVDF chelating membrane in the presence of coexistent cations and organic acids.

    PubMed

    Song, Laizhou; Zhao, Xiaodan; Fu, Jie; Wang, Xiuli; Sheng, Yiping; Liu, Xiaowei

    2012-01-15

    Melamine-diethylenetriaminepentaacetic acid/polyvinylidene fluoride (MA-DTPA/PVDF) chelating membrane bearing polyaminecarboxylate groups was used to remove Ni(II) from nickel plating effluents. Adsorption experiments were conducted to study the adsorption of the membrane towards Ni(II) in Ni(II)-Ca(II), Ni(II)-NH(4)(+), Ni(II)-Fe(III) binary systems, and Ni(II)-lactic acid, Ni(II)-succinic acid and Ni(II)-citric acid complex systems. For the ternary nickel plating processes, the effects of 3d transition metals including Fe(II), Co(II), Cu(II) and Zn(II) on Ni(II) adsorption were evaluated. The influences of the aforementioned coexistent cations and organic acids were elucidated by the continuum solvation model (COSMO)-corrected density functional theory (DFT) method. Geometries and complexation energies were analyzed for metal-MA-DTPA and Ni(II)-organic acid complexes. DFT results accord with the experimental data, indicating that DFT is helpful to evaluate the complexation between the membrane and metal cations. The coexistent Ca(II) tends to form more stable complex with MA-DTPA ligand than NH(4)(+) and Fe(III), and can interfere with the formation of Ni(II)-MA-DTPA complex. The complexing sequence of 3d metals with MA-DTPA ligand is Zn(II)). Therefore, both Fe(II) and Cu(II) have the considerable competition with Ni(II). The stabilities of Ni(II)-organic acid complexes follow the order of lactic acidII)-MA-DTPA complex.

  13. A novel mutation in the alpha-helix 1 of the C subunit of the F(1)/F(0) ATPase responsible for optochin resistance of a Streptococcus pneumoniae clinical isolate.

    PubMed

    Cogné, N; Claverys, J; Denis, F; Martin, C

    2000-10-01

    Previously reported mutations involved in optochin resistance of Streptococcus pneumoniae clinical isolates changed residues 48, 49 or 50, in the transmembrane alpha-helix 2 of the F(1)/F(0) ATPase subunit. We report here an unusual mutation which changes the sequence of the transmembrane alpha-helix 1 of the AtpC subunit. This mutation involves a Gly to Ser substitution resulting from a G to A transition at codon 14 of the atpC gene.

  14. Conventional s-Wave Superconductivity in BiS2-Based NdO0.71F0.29BiS2 Revealed by Thermal Transport Measurements

    NASA Astrophysics Data System (ADS)

    Yamashita, Takuya; Tokiwa, Yoshifumi; Terazawa, Daiki; Nagao, Masanori; Watauchi, Satoshi; Tanaka, Isao; Terashima, Takahito; Matsuda, Yuji

    2016-07-01

    To study the superconducting gap structure of BiS2-based layered compound NdO0.71F0.29BiS2 (Tc = 5 K), we measured the thermal conductivity κ, which is a sensitive probe of low-energy quasiparticle spectrum. In the absence of a magnetic field, residual linear term in the thermal conductivity κ0/T at T → 0 is vanishingly small, indicating that the residual normal fluid, which is expected for nodal superconductors, is absent. Moreover, the applied magnetic field hardly affects thermal conductivity in wide range of the vortex state, indicating the absence of Doppler shifted quasiparticles. These results provide evidence that NdO0.71F0.29BiS2 is a fully gapped superconductor. The obtained gap structure, along with the robustness of the superconductivity against the impurity, suggest a conventional s-wave superconducting state in NdO0.71F0.29BiS2.

  15. Anisotropy and Vortex Pinning of Heavy Ion irradiated SmFeAsO0.8F0.15 and BaFe2(As1-xPx)2 Crystals

    NASA Astrophysics Data System (ADS)

    Kwok, Wai-Kwong; Fang, Lei; Chaparro, Carlos; Jia, Ying; Welp, Ulrich; Koshelev, Alexei; Xu, Shaofei; Crabtree, George; Karpinski, Janusz

    2012-02-01

    We report specific heat and magnetization measurements on SmFeAsO0.8F0.15 and BaFe2(As1-xPx)2 single crystals irradiated with high energy heavy ions of 1.4GeV Pb to dose matching fields up to 4 Tesla. We find a nearly one half reduction in the superconducting anisotropy and doubling of the irreversibility field in SmFeAsO0.8F0.15 after irradiation and virtually no change in the zero-field superconducting transition temperature. In both SmFeAsO0.8F0.15 and BaFe2(As1-xPx)2 crystals, we find a substantial increase in the critical current determined from SQUID and micro-Hall probe magnetization measurements. Pinning force analysis on proton and heavy ion irradiated pristine overdoped BaFe2(As1-xPx)2 crystals indicates presence of induced δTc-type pinning defects in these samples.

  16. Pressure-induced phase transitions and correlation between structure and superconductivity in iron-based superconductor Ce(O(0.84)F(0.16))FeAs.

    PubMed

    Zhao, Jinggeng; Liu, Haozhe; Ehm, Lars; Dong, Dawei; Chen, Zhiqiang; Liu, Qingqing; Hu, Wanzheng; Wang, Nanlin; Jin, Changqing

    2013-07-15

    High-pressure angle-dispersive X-ray diffraction experiments on iron-based superconductor Ce(O(0.84)F(0.16))FeAs were performed up to 54.9 GPa at room temperature. A tetragonal to tetragonal isostructural phase transition starts at about 13.9 GPa, and a new high-pressure phase has been found above 33.8 GPa. At pressures above 19.9 GPa, Ce(O(0.84)F(0.16))FeAs completely transforms to a high-pressure tetragonal phase, which remains in the same tetragonal structure with a larger a-axis and smaller c-axis than those of the low-pressure tetragonal phase. The structure analysis shows a discontinuity in the pressure dependences of the Fe-As and Ce-(O, F) bond distances, as well as the As-Fe-As and Ce-(O, F)-Ce bond angles in the transition region, which correlates with the change in T(c) of this compound upon compression. The isostructural phase transition in Ce(O(0.84)F(0.16))FeAs leads to a drastic drop in the superconducting transition temperature T(c) and restricts the superconductivity at low temperature. For the 1111-type iron-based superconductors, the structure evolution and following superconductivity changes under compression are related to the radius of lanthanide cations in the charge reservoir layer.

  17. Electronic anisotropy from magneto-transport near Tc in SmFeAs(O0.7F0.25) and (Ba,Rb)Fe2As2 single crystals

    NASA Astrophysics Data System (ADS)

    Moll, Philip; Kunze, Karsten; Bukowski, Zbigniew; Zhigadlo, Nikolai; Karpinski, Janusz; Batlogg, Bertram

    2009-03-01

    We derived thermally activated flux flow (TAFF) activation energies Ea(H) and the upper critical fields Hc2(T) parallel to the c-axis and in the Lorentz-force free configuration (H || ab || j) of SmFeAs(O0.7F0.25) and (Ba,Rb)Fe2As2 single crystals from resistance measurements and compare them to the ones reported for other REFeAs(OF). A perfectly rectangular rod (67x11x4 μm), aligned with the crystal axes, was cut from a larger SmFeAs(O0.7F0.25) single crystal (˜ 200 μm) by a Focused Ion Beam (FIB) which allowed us to precisely control its geometry factor L/A = 0.89 1/μm. The FIB was also used to deposit 4 Pt contacts. We found a slope of Hc2, 50% (T), parallel to the c-axis, of 1.9 T/K for SmFeAs(O0.7F0.25) and 3.7 T/K for (Ba,Rb)Fe2As2 near Tc. The electronic anisotropy, derived from magneto-transport, is significantly larger in the REFeAs(OF) crystals than in (Ba,Rb)Fe2As2.

  18. Theoretical investigation of GaAsBi/GaAsN tunneling field-effect transistors with type-II staggered tunneling junction

    NASA Astrophysics Data System (ADS)

    Wang, Yibo; Liu, Yan; Han, Genquan; Wang, Hongjuan; Zhang, Chunfu; Zhang, Jincheng; Hao, Yue

    2017-06-01

    We investigate GaAsBi/GaAsN system for the design of type-II staggered hetero tunneling field-effect transistor (hetero-TFET). Strain-symmetrized GaAsBi/GaAsN with effective lattice match to GaAs exhibits a type-II band lineup, and the effective bandgap EG,eff at interface is significantly reduced with the incorporation of Bi and N elements. The band-to-band tunneling (BTBT) rate and drive current of GaAsBi/GaAsN hetero-TFETs are boosted due to the utilizing of the type-II staggered tunneling junction with the reduced EG,eff. Numerical simulation shows that the drive current and subthreshold swing (SS) characteristics of GaAsBi/GaAsN hetero-TFETs are remarkably improved by increasing Bi and N compositions. The dilute content GaAs0.85Bi0.15/GaAs0.92N0.08 staggered hetero-nTFET achieves 7.8 and 550 times higher ION compared to InAs and In0.53Ga0.47As homo-TFETs, respectively, at the supply voltage of 0.3 V. GaAsBi/GaAsN heterostructure is a potential candidate for high performance TFET.

  19. Investigation of simultaneous biosorption of copper(II) and chromium(VI) on dried Chlorella vulgaris from binary metal mixtures: Application of multicomponent adsorption isotherms

    SciTech Connect

    Aksu, Z.; Acikel, U.; Kutsal, T.

    1999-02-01

    Although the biosorption of single metal ions to various kinds of microorganisms has been extensively studied and the adsorption isotherms have been developed for only the single metal ion situation, very little attention has been given to the bioremoval and expression of adsorption isotherms of multimetal ions systems. In this study the simultaneous biosorption of copper(II) and chromium(VI) to Chlorella vulgaris from a binary metal mixture was studied and compared with the single metal ion situation in a batch stirred system. The effects of pH and single- and dual-metal ion concentrations on the equilibrium uptakes were investigated. In previous studies the optimum biosorption pH had been determined as 4.0 for copper(II) and as 2.0 for chromium(VI). Multimetal ion biosorption studies were performed at these two pH values. It was observed that the equilibrium uptakes of copper(II) or chromium(VI) ions were changed due to the biosorption pH and the presence of other metal ions. Adsorption isotherms were developed for both single- and dual-metal ions systems at these two pH values, and expressed by the mono- and multicomponent Langmuir and Freundlich adsorption models. Model parameters were estimated by nonlinear regression. It was seen that the adsorption equilibrium data fitted very well to the competitive Freundlich model in the concentration ranges studied.

  20. Investigation of antitumor potential of Ni(II) complexes with tridentate PNO acylhydrazones of 2-(diphenylphosphino)benzaldehyde and monodentate pseudohalides.

    PubMed

    Čobeljić, Božidar; Milenković, Milica; Pevec, Andrej; Turel, Iztok; Vujčić, Miroslava; Janović, Barbara; Gligorijević, Nevenka; Sladić, Dušan; Radulović, Siniša; Jovanović, Katarina; Anđelković, Katarina

    2016-04-01

    Square-planar azido Ni(II) complex with condensation product of 2-(diphenylphosphino)benzaldehyde and Girard's T reagent was synthesized and its crystal structure was determined. Cytotoxic activity of the azido complex and previously synthesized isothiocyanato, cyanato and chlorido Ni(II) complexes with this ligand was examined on six tumor cell lines (HeLa, A549, K562, MDA-MB-453, MDA-MB-361 and LS-174) and two normal cell line (MRC-5 and BEAS-2B). All the investigated nickel(II) complexes were cytotoxic against all tumor cell lines. The newly synthesized azido complex showed selectivity to HeLa and A549 tumor cell lines compared to the normal cells (for A549 IC50 was similar to that of cisplatin). Azido complex interferes with cell cycle phase distribution of A549 and HeLa cells and possesses nuclease activity towards supercoiled DNA. The observed selectivity of the azido complex for some tumor cell lines can be connected with its strong DNA damaging activity.

  1. Theoretical investigation of the magnetic exchange interactions in copper(II) oxides under chemical and physical pressures.

    PubMed

    Rocquefelte, Xavier; Schwarz, Karlheinz; Blaha, Peter

    2012-01-01

    It remains a challenge to understand the unconventional mechanisms that cause high-T(C) superconductivity in cuprate superconductors, high-T(C) multiferroicity in CuO, or low-dimensional magnetism in the spin-Peierls transition compounds such as CuGeO(3). A common feature of all these copper oxide compounds (containing Cu(2+) ions) is the presence of large magnetic superexchange interactions J. It is a general strategy to apply chemical and/or physical pressure in order to tune these exotic properties. Here we show theoretically, for the first time, the impact of physical pressure on J on CuO, for which we predict a strong enhancement of the low-dimensionality of the magnetic interactions and the spin-frustration at high-pressures. Such modifications are expected to strongly influence the multiferroic properties of CuO. We finally demonstrate that PBE0 hybrid DFT calculations provide reliable J values for a wide range of copper(II) oxides compounds, i.e. CuGeO(3), BaCu(2)Si(2)O(7), BaCu(2)Ge(2)O(7), and La(2)CuO(4).

  2. Level II Cultural Resource investigation for the Texoma Distribution Enhancements project, Cameron and Calcasieu Parishes, Louisiana: Final report

    SciTech Connect

    LeeDecker, C. H.; Holland, C. C.

    1987-10-01

    A Level II Cultural Resource Survey was completed for the Texoma Distribution Enhancements project, located in Cameron and Calcasieu Parishes, Louisiana. The 13-mile pipeline extends from Strategic Petroleum Reserve No. 3 to a terminus near Vincent Landing. Located in Louisiana's southwest coastal zone, the pipeline will traverse extensive marsh lands as well as upland prairie terrace areas. Present land use within the project area consists primarily of undeveloped marsh land and cattle range. The study methods included background research, intensive pedestrian survey with systematic shovel testing, a boat survey, and laboratory analysis of recovered artifact collections. One historic site, 16CU205, was identified during the field survey, and it was tested for National Register eligibility. The site is assignable to the Industrialization and Modernization (1890-1940) Cultural Unit. Archaeological testing indicates that it is a rural residence or farmstead, with a house and one outbuilding within the proposed right-of-way. The site lacks significant historical association and sufficient archaeological integrity to merit inclusion on the National Register of Historic Places. Four standing structures were also identified during the field survey. The structures are agricultural outbuildings, less than 40 years in age, that possess no architectural distinction or historical association. They have been documented photographically and by scaled plan drawings, but do not merit additional study prior to their destruction. 24 refs., 15 figs., 3 tabs.

  3. Investigate the ultrasound energy assisted adsorption mechanism of nickel(II) ions onto modified magnetic cobalt ferrite nanoparticles: Multivariate optimization.

    PubMed

    Mehrabi, Fatemeh; Alipanahpour Dil, Ebrahim

    2017-07-01

    In present study, magnetic cobalt ferrite nanoparticles modified with (E)-N-(2-nitrobenzylidene)-2-(2-(2-nitrophenyl)imidazolidine-1-yl) ethaneamine (CoFe2O4-NPs-NBNPIEA) was synthesized and applied as novel adsorbent for ultrasound energy assisted adsorption of nickel(II) ions (Ni(2+)) from aqueous solution. The prepared adsorbent characterized by Fourier transforms infrared spectroscopy (FT-IR), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and X-ray diffraction (XRD). The dependency of adsorption percentage to variables such as pH, initial Ni(2+) ions concentration, adsorbent mass and ultrasound time were studied with response surface methodology (RSM) by considering the desirable functions. The quadratic model between the dependent and independent variables was built. The proposed method showed good agreement between the experimental data and predictive value, and it has been successfully employed to adsorption of Ni(2+) ions from aqueous solution. Subsequently, the experimental equilibrium data at different concentration of Ni(2+) ions and 10mg amount of adsorbent mass was fitted to conventional isotherm models like Langmuir, Freundlich, Tempkin, Dubinin-Radushkevich and it was revealed that the Langmuir is best model for explanation of behavior of experimental data. In addition, conventional kinetic models such as pseudo-first and second-order, Elovich and intraparticle diffusion were applied and it was seen that pseudo-second-order equation is suitable to fit the experimental data. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Emerging drugs for antipsychotic-induced tardive dyskinesia: investigational drugs in Phase II and Phase III clinical trials.

    PubMed

    Lockwood, Jonathan Tomas; Remington, Gary

    2015-09-01

    Antipsychotic drugs (APs) represent the mainstay of treatment for schizophrenia and other forms of psychosis. Tardive dyskinesia (TD) is a motor disorder associated with the ongoing use of APs and is characterized by involuntary, repetitive movements that are potentially irreversible. Current treatment is wanting, due in part to our limited understanding of the mechanisms underlying TD. Risk of TD associated with APs appears linked to continuous blockade of dopamine D2 receptors in the basal ganglia. Proposed mechanisms include increased dopamine activation of D2 receptors caused by supersensitivity and neurodegeneration of dopamine-producing neurons due to biochemical changes incurred by ongoing AP exposure. Existing treatments are designed to reverse or prevent the neurochemical/biological changes caused by dopamine D2 receptor blockade and include vesicular monoamine transporter (VMAT) inhibitors, antioxidants, compounds with serotonin receptor agonism as well as antagonism, GABA agonists and cholinergic agents. Randomized, controlled trials in Phase II and Phase III (ClinicalTrials.org/ClinicalTrialsRegister.eu) are summarized and discussed. Effective adjunctive treatment for the symptoms of TD will depend on gaining a better understanding of the neurological changes induced by chronic dopamine D2 receptor antagonism from APs.

  5. Preliminary Results of Nene II Engine Altitude-chamber Performance Investigation. 2; Altitude Performance using 18.41-inch Diameter-jet Nozzle

    NASA Technical Reports Server (NTRS)

    Armstron, J. C.; Wilsted, H. D.; Vincent, K. R.

    1948-01-01

    An investigation is being conducted to determine the altitude performance characteristics of the Nene II engine and its components. The present paper presents preliminary results obtained using a jet nozzle of 18.41 inches in diameter, giving an area equal to 96.4 percent of the area of the standard jet nozzle of this engine. The test results presented are for conditions simulating altitudes from seal level to 50,000 feet and ram-pressure ratios from 1.00 to 2.70. The ram pressure ratios correspond to flight Mach numbers between zero and 1.28.

  6. Toxicity of Cu (II) to the green alga Chlorella vulgaris: a perspective of photosynthesis and oxidant stress.

    PubMed

    Chen, Zunwei; Song, Shufang; Wen, Yuezhong; Zou, Yuqin; Liu, Huijun

    2016-09-01

    The toxic effects of Cu (II) on the freshwater green algae Chlorella vulgaris and its chloroplast were investigated by detecting the responses of photosynthesis and oxidant stress. The results showed that Cu (II) arrested the growth of C. vulgaris and presented in a concentration- and time-dependent trend and the SRichards 2 model fitted the inhibition curve best. The chlorophyll fluorescence parameters, including qP, Y (II), ETR, F v /F m , and F v /F 0, were stimulated at low concentration of Cu (II) but declined at high concentration, indicating the photosystem II (PSII) of C. vulgaris was destroyed by Cu (II). The chloroplasts were extracted, and the Hill reaction activity (HRA) of chloroplast was significantly decreased with the increasing Cu (II) concentration under both illuminating and dark condition, and faster decline speed was observed under dark condition. Activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were also significantly decreased at high concentration Cu (II), companied with a large number of reactive oxygen species (ROS) production. All these results indicated a severe oxidative stress on algal cells occurred as well as the effect on photosynthesis, thus inhibiting the growth of algae, which providing sights to evaluate the phytotoxicity of Cu (II).

  7. Recent innovations in the USA National Cancer Institute-sponsored investigator initiated Phase I and II anticancer drug development

    PubMed Central

    Bando, Hideaki; Takebe, Naoko

    2015-01-01

    Exciting recent advancements in deep-sequencing technology have enabled a rapid and cost-effective molecular characterization of patient-derived tumor samples. Incorporating these innovative diagnostic technologies into early clinical trials could significantly propel implementation of precision medicine by identifying genetic markers predictive of sensitivity to agents. It may also markedly accelerate drug development and subsequent regulatory approval of novel agents. Particularly noteworthy, a high-response rate in a Phase II trial involving a biomarker-enriched patient cohort could result in a regulatory treatment approval in rare histologies, which otherwise would not be a candidate for a large randomized clinical trial. Furthermore, even if a trial does not meet its statistical endpoint, tumors from a few responders should be molecularly characterized as part of the new biomarker-mining processes. In order to accommodate patient screening and accelerate the accrual process, institutions conducting early clinical trials need to be a part of a multi-institution clinical trials network. Future clinical trial design will incorporate new biomarkers discovered by a ‘phenotype-to-genotype’ effort with an appropriate statistical design. To help advance such changes, the National Cancer Institute has recently reformed the existing early phase clinical trials network. A new clinical trial network, the Experimental Therapeutics Clinical Trials Network (ET-CTN), was begun and, in addition to its pre-existing infrastructure, an up-to-date clinical trial registration system, clinical trial monitoring system including electronic database and a central Institutional Review Board were formed. Ultimately, these reforms support identifying the most appropriate therapy for each tumor type by incorporating state-of-the-art molecular diagnostic tools into early clinical trials. PMID:26423340

  8. NMR investigations of dinuclear, single-anion bridged copper(II) metallacycles: structure and antiferromagnetic behavior in solution.

    PubMed

    Reger, Daniel L; Pascui, Andrea E; Pellechia, Perry J; Ozarowski, Andrew

    2013-11-04

    The nuclear magnetic resonance (NMR) spectra of single-anion bridged, dinuclear copper(II) metallacycles [Cu2(μ-X)(μ-L)2](A)3 (L(m) = m-bis[bis(1-pyrazolyl)methyl]benzene: X = F(-), A = BF4(-); X = Cl(-), OH(-), A = ClO4(-); L(m)* = m-bis[bis(3,5-dimethyl-1-pyrazolyl)methyl]benzene: X = CN(-), F(-), Cl(-), OH(-), Br(-), A = ClO4(-)) have relatively sharp (1)H and (13)C NMR resonances with small hyperfine shifts due to the strong antiferromagnetic superexchange interactions between the two S = 1/2 metal centers. The complete assignments of these spectra, except X = CN(-), have been made through a series of NMR experiments: (1)H-(1)H COSY, (1)H-(13)C HSQC, (1)H-(13)C HMBC, T1 measurements and variable-temperature (1)H NMR. The T1 measurements accurately determine the Cu···H distances in these molecules. In solution, the temperature dependence of the chemical shifts correlate with the population of the paramagnetic triplet (S = 1) and diamagnetic singlet (S = 0) states. This correlation allows the determination of antiferromagnetic exchange coupling constants, -J (Ĥ = -JŜ1Ŝ2), in solution for the L(m) compounds 338(F(-)), 460(Cl(-)), 542(OH(-)), for the L(m)* compounds 128(CN(-)), 329(F(-)), 717(Cl(-)), 823(OH(-)), and 944(Br(-)) cm(-1), respectively. These values are of similar magnitudes to those previously measured in the solid state (-Jsolid = 365, 536, 555, 160, 340, 720, 808, and 945 cm(-1), respectively). This method of using NMR to determine -J values in solution is an accurate and convenient method for complexes with strong antiferromagnetic superexchange interactions. In addition, the similarity between the solution and solid-state -J values of these complexes confirms the information gained from the T1 measurements: the structures are similar in the two states.

  9. Response to Discussion of "Investigation of Oxide Bifilms in Investment Cast Superalloy IN100 Part I and II"

    NASA Astrophysics Data System (ADS)

    Kaplan, M. A.; Fuchs, G. E.

    2017-10-01

    In his most recent letter (Campbell in Met Trans A, 2017), Professor Campbell provides additional comments on Kaplan and Fuchs papers "Oxides Bifilms in Superalloy: IN100, Parts I and II (Met Trans A 47A:2346-2361, 2016; Met Trans A 47A:2362-2375, 2016) and on their response to his initial comments (Met Trans A 47A:3806-3809, 2016). In this recent submission, Campbell provides some very interesting thoughts on why bifilms were not observed by Kaplan and Fuchs and creates a new theory for the formation of defects referred to as bifilms. However, Campbell again provides no evidence to substantiate the presence of bifilms in Ni-base superalloys or his newly theorized mechanism. The vast majority of Campbell's comments are based solely on the re-interpretation of the photomicrographs and the data reported in the literature, including those presented by Kaplan and Fuchs (Met Trans A 47A:2346-2361, 2016; Met Trans A 47A:2362-2375, 2016). Campbell claims that bifilms are present throughout Ni-base superalloys, even though no one else has reported the presence of bifilms in Ni-base superalloys. In re-interpreting the data and images, Campbell ignores the extensive surface characterization results reported by Kaplan and Fuchs (Met Trans A 47A:2346-2361, 2016; Met Trans A 47A:2362-2375, 2016) that clearly indicate that there are no oxide films or bifilms on the fracture surfaces examined. Please note that this discussion of Campbell's most recent letter will be limited to Ni-base superalloys, since that is the subject of the research reported by Kaplan and Fuchs.

  10. Recent innovations in the USA National Cancer Institute-sponsored investigator initiated Phase I and II anticancer drug development.

    PubMed

    Bando, Hideaki; Takebe, Naoko

    2015-11-01

    Exciting recent advancements in deep-sequencing technology have enabled a rapid and cost-effective molecular characterization of patient-derived tumor samples. Incorporating these innovative diagnostic technologies into early clinical trials could significantly propel implementation of precision medicine by identifying genetic markers predictive of sensitivity to agents. It may also markedly accelerate drug development and subsequent regulatory approval of novel agents. Particularly noteworthy, a high-response rate in a Phase II trial involving a biomarker-enriched patient cohort could result in a regulatory treatment approval in rare histologies, which otherwise would not be a candidate for a large randomized clinical trial. Furthermore, even if a trial does not meet its statistical endpoint, tumors from a few responders should be molecularly characterized as part of the new biomarker-mining processes. In order to accommodate patient screening and accelerate the accrual process, institutions conducting early clinical trials need to be a part of a multi-institution clinical trials network. Future clinical trial design will incorporate new biomarkers discovered by a 'phenotype-to-genotype' effort with an appropriate statistical design. To help advance such changes, the National Cancer Institute has recently reformed the existing early phase clinical trials network. A new clinical trial network, the Experimental Therapeutics Clinical Trials Network (ET-CTN), was begun and, in addition to its pre-existing infrastructure, an up-to-date clinical trial registration system, clinical trial monitoring system including electronic database and a central Institutional Review Board were formed. Ultimately, these reforms support identifying the most appropriate therapy for each tumor type by incorporating state-of-the-art molecular diagnostic tools into early clinical trials.

  11. AN INVESTIGATION OF THE TRAINING AND SKILL REQUIREMENTS OF INDUSTRIAL MACHINERY MAINTENANCE WORKERS. VOLUME II. FINAL REPORT.

    ERIC Educational Resources Information Center

    LYNN, FRANK

    THE APPENDIXES FOR "AN INVESTIGATION OF THE TRAINING AND SKILL REQUIREMENTS OF INDUSTRIAL MACHINERY MAINTENANCE WORKERS, FINAL REPORT, VOLUME I" (VT 004 006) INCLUDE (1) TWO LETTERS FROM PLANT ENGINEERS STRESSING THE IMPORTANCE OF TRAINING MACHINERY MAINTENANCE WORKERS, (2) A DESCRIPTION OF THE MAINTENANCE TRAINING SURVEY, A SAMPLE QUESTIONNAIRE,…

  12. Investigating Students' Mental Models and Knowledge Construction of Microscopic Friction. II. Implications for Curriculum Design and Development

    ERIC Educational Resources Information Center

    Corpuz, Edgar D.; Rebello, N. Sanjay

    2011-01-01

    Our previous research showed that students' mental models of friction at the atomic level are significantly influenced by their macroscopic ideas. For most students, friction is due to the meshing of bumps and valleys and rubbing of atoms. The aforementioned results motivated us to further investigate how students can be helped to improve their…

  13. Investigating Students' Mental Models and Knowledge Construction of Microscopic Friction. II. Implications for Curriculum Design and Development

    ERIC Educational Resources Information Center

    Corpuz, Edgar D.; Rebello, N. Sanjay

    2011-01-01

    Our previous research showed that students' mental models of friction at the atomic level are significantly influenced by their macroscopic ideas. For most students, friction is due to the meshing of bumps and valleys and rubbing of atoms. The aforementioned results motivated us to further investigate how students can be helped to improve their…

  14. An Investigation of Factors Relating to Retention of Student-Athletes Participating in NCAA Division II Athletics

    ERIC Educational Resources Information Center

    Weiss, Stephen M.; Robinson, Tracey L.

    2013-01-01

    Most studies investigating retention of college students have broadly looked at the entire student population. Few attempts have been made to determine if there are specific issues related to the retention of student-athletes. Factors involved in retaining student-athletes were examined by surveying two groups of participants currently enrolled or…

  15. Excited State Investigation of a New Ru(II) Complex for Dual Reactivity with Low Energy Light

    PubMed Central

    Knoll, J. D.; Albani, B. A.; Turro, C.

    2015-01-01

    The new complex [Ru(tpy)(Me2dppn)(py)]2+ efficiently photodissociates py in CH3CN with Φ500 = 0.053(1) induced by steric bulk from methyl substituents and produces 1O2 with ΦΔ = 0.69(9) from its long-lived 3ππ* excited state. The unique excited state processes that result in dual reactivity were investigated using ultrafast transient absorption spectroscopy. PMID:25912170

  16. An Investigation of the Ranger V-770-8 Engine Installation for the Edo XOSE-1 Airplane II : Aerodynamics

    NASA Technical Reports Server (NTRS)

    Dennard, John S.

    1945-01-01

    Investigations were made to determine the cowling and cooling characteristics of the Ranger V-770-8 engine installation in an observation seaplane. Final cowl configurations possessed ample engine and oil-cooler pressure drops for cooling in the critical normal-power climb condition with any of the three baffle configurations tested. The indicated critical Mach number of the cowling was found to be 0.70 as determined by the pressure on the lower lip of the inlet.

  17. Investigation of the difficulties associated with the use of lead telluride and other II - IV compounds for thin film thermistors

    NASA Technical Reports Server (NTRS)

    Mclennan, W. D.

    1975-01-01

    The fabrication of thermistors was investigated for use as atmospheric temperature sensors in meteorological rocket soundings. The final configuration of the thin film thermistor is shown. The composition and primary functions of the six layers of the sensor are described. A digital controller for thin film deposition control is described which is capable of better than .1 A/sec rate control. The computer program modules for digital control of thin film deposition processing are included.

  18. Synthesis, Spectral Characterization, SEM, Antimicrobial, Antioxidative Activity Evaluation, DNA Binding and DNA Cleavage Investigation of Transition Metal(II) Complexes Derived from a tetradentate Schiff base bearing thiophene moiety.

    PubMed

    Abdel Aziz, Ayman A; Seda, Sabry H

    2017-03-01

    A novel series of Co(II), Ni(II), Cu(II) and Zn(II) mononuclear complexes have been synthesized involving a potentially tetradentate Schiff base ligand, which was obtained by condensation of 2-aminophenol with 2,5-thiophene-dicarboxaldehyde. The complexes were synthesized via reflux reaction of methanolic solution of the appropriate Schiff base ligand with one equivalent of corresponding metal acetate salt. Based on different techniques including micro analysis, FT-IR, NMR, UV-Vis, ESR, ESI-mass and conductivity measurements, four-coordinated geometry was assigned for all complexes. Spectroscopic data have shown that, the reported Schiff base coordinated to metal ions as a dibasic tetradentate ligand through the phenolic oxygen and the azomethine nitrogen. The antimicrobial activities of the parent ligand and its complexes were investigated by using the agar disk diffusion method. Antioxidation properties of the novel complexes were investigated and it was found that all the complexes have good radical scavenging properties. The binding of complexes to calf thymus DNA (CT-DNA) was investigated by absorption, emission and viscosity measurements. Binding studies have shown that all the complexes interacted with CT-DNA via intercalation mode and the binding affinity varies with relative order as Cu(II) complex > Co(II) complex > Zn(II) complex > Ni(II) complex. Furthermore, DNA cleavage properties of the metal complexes were also investigated. The results suggested the possible utilization of novel complexes for pharmaceutical applications.

  19. Female Sex Pheromone of the Cone Moth, Dioryctria mendacella: Investigation of Synergism between Type I and Type II Pheromone Components.

    PubMed

    Hall, David R; Farman, Dudley; Domínguez, Juan C; Pajares, Juan A

    2017-05-01

    Polyunsaturated hydrocarbons (Type II pheromone components) have been reported to be synergists for unsaturated acetates, alcohols or aldehydes (Type I components) in the sex pheromones of several species of Lepidoptera. However, there is some debate over whether the active components are the hydrocarbons themselves or more volatile degradation products. Extracts of pheromone glands of adult females of the cone moth, Dioryctria mendacella (Lepidoptera: Pyralidae), contain (Z,E)-9,11-tetradecadienyl acetate (ZE9,11-14:Ac) and at least ten times as much (Z,Z,Z,Z,Z)-3,6,9,12,15-pentacosapentaene (ZZZZZ3,6,9,12,15-25:H). The former elicits a strong electroantennogram response from males while no response could be recorded to the latter. In field trapping tests, both compounds were individually unattractive to male D. mendacella moths, but blends of the two compounds containing at least a 10:1 ratio of ZZZZZ3,6,9,12,15-25:H : ZE9,11-14:Ac were highly attractive. The relatively involatile hydrocarbon was shown to be released from the dispensers used and no significant degradation could be detected. Furthermore, blends of ZE9,11-14:Ac and analogs of ZZZZZ3,6,9,12,15-25:H with fewer carbons and/or double bonds that might be expected to produce similar degradation products to ZZZZZ3,6,9,12,15-25:H were unattractive. This indicated a specific response to the hydrocarbon itself, further substantiated by the observation that related hydrocarbons did not interfere with the activity of ZZZZZ3,6,9,12,15-25:H. Thus a three-step conversion of fish oil was used to produce a blend of unsaturated hydrocarbons containing ZZZZZ3,6,9,12,15-25:H as the major component, albeit only 30% of the total, and a blend of this material with ZE9,11-14:Ac was as attractive to male D. mendacella moths as blends with an equivalent amount of the purified material. This mixture of unsaturated hydrocarbons is much cheaper to produce than the pure pentaene, and may be useful in lures for other species

  20. The PICASSO project: MT Investigation in Southern Spain and Morocco - Results of phase I and outlook on phase II

    NASA Astrophysics Data System (ADS)

    Kiyan, D.; Schmoldt, J.; Jones, A. G.; Hogg, C.; Rosell, O.

    2009-12-01

    PICASSO (Project to Investigate Convective Alboran Sea System Overturn) is an international, multi-disciplinary project that aims to improve knowledge of the internal structure and plate-tectonic processes in the highly complex three-dimensional region formed by the collision of the African and European plate under the effect of the Mediterranean plate motion. The first phase of the DIAS magnetotelluric (MT) component of the PICASSO project was carried out in Southern Spain from Sept.-Nov., 2007 focused on the investigation of the internal structure of the Betic Mountain Chain and the Iberian Basement. Two different types of magnetotelluric (MT) equipment - broadband (BBMT) and long period (LMT) MT - were used along a profile from the outskirts of Madrid to the Mediterranean Sea through the Betic Mountain Chain. The modified acquisition design of one of the equipment types (the LVIV LEMI long period system), with separate recording of each telluric channel, allowed for advanced investigation of the acquired dataset. The data were processed using four different robust algorithms, and the different responses have been compared. A distinct separation can be made between the Betics region of Alpine orogeny in the south and the Variscan Iberian Massif beneath the north of the profile in terms of their inherent electric conductivity characteristics. Models derived by two-dimensional inversions of regional responses, after removing distortion effects, from this first phase show a remarkably complex subsurface structure beneath the region of the External Betic Chain. Strike direction varies along the profile and with depth due to the intricate morphology, and its choice has significant impact on the responses to be modelled and thereby provides a challenging framework for MT data interpretation. The second phase of PICASSO aims to shed light onto the origin of the Atlas Mountain Chain and test hypotheses for its missing mantle root derived from heat flow, gravity, geoid

  1. Coumarins in the gaseous phase. II. Investigation of stimulated emission from coumarin vapors in the range 470--540 nm

    SciTech Connect

    Logunov, O.A.; Startsev, A.V.; Stoilov, Y.Y.

    1981-06-01

    An investigation was made of the spectral and time characteristics of lasers utilizing coumarin 7 (C7, C153, C30, 7-diethylamino-3(2'-benzoxazolyl)-coumarin, and C6 vapors mixed with buffer gases (approx.35 atm) and kept at 200 /sup 0/C. The lasing efficiency in the region of 500 nm exceeded 6% and the threshold pump intensities were below 0.3 MW/cm/sup 2/, so that it should be possible to construct efficient cw and pulsed tunable gas lasers emitting in the blue-green part of the spectrum.

  2. Numerical investigations with a hybrid isentropic-sigma model. I - Normal-mode characteristics. II - The inclusion of moist processes

    NASA Technical Reports Server (NTRS)

    Pierce, R. B.; Johnson, Donald R.; Reames, Fred M.; Zapotocny, Tom H.; Wolf, Bart J.

    1991-01-01

    The normal-mode characteristics of baroclinically amplifying disturbances were numerically investigated in a series of adiabatic simulations by a hybrid isentropic-sigma model, demonstrating the effect of coupling an isentropic-coordinate free atmospheric domain with a sigma-coordinate PBL on the normal-mode characteristics. Next, the normal-mode model was modified by including a transport equation for water vapor and adiabatic heating by condensation. Simulations with and without a hydrological component showed that the overall effect of latent heat release is to markedly enhance cyclogenesis and frontogenesis.

  3. Investigations in Time and of Space Using the FIRST Survey: Radio Source Variability and the Evolution of FR II Quasars

    NASA Astrophysics Data System (ADS)

    Thyagarajan, Nithyanandan

    than with Friedmann models. These earlier results can be attributed to a combination of selection effects, sample definition problems, and inconsistencies in analysis. However, some recent and more successful analyses have still failed to distinguish among different Friedmann models. A catalog of ∼ 680 FR II quasars was constructed from the FIRST sources with redshifts taken from the SDSS spectroscopic QSO catalog and a similar sized sample from the SDSS photometric QSO catalog which are the largest quasar compilations to date. Using statistical analyses, no evidence for intrinsic evolution of sizes with redshift is found. A static Euclidean model for the universe is clearly ruled out. However, new degeneracies between parameters in the multi-dimensional χ2-surface are found which can only be resolved with additional, independent information. Notable differences are found between the spectroscopic and photometric samples raising questions about the nature and origin of these populations.

  4. Physical Investigations of Small Particles: (I) Aerosol Particle Charging and Flux Enhancement and (II) Whispering Gallery Mode Sensing

    NASA Astrophysics Data System (ADS)

    Lopez-Yglesias, Xerxes

    of the molecule and the electromagnetic interaction between the molecule and particle, especially for the neutral particle case, are completely ignored, or, as is often the case for a permanent dipole vapor species, strongly underestimated. Comparing our model to these classical models we determine an "enhancement factor" to characterize how important the addition of these physical parameters and processes is to the understanding of particle nucleation and growth. Part II: Whispering gallery mode (WGM) optical biosensors are capable of extraordinarily sensitive specific and non-specific detection of species suspended in a gas or fluid. Recent experimental results suggest that these devices may attain single-molecule sensitivity to protein solutions in the form of stepwise shifts in their resonance wavelength, lambdaR, but present sensor models predict much smaller steps than were reported. This study examines the physical interaction between a WGM sensor and a molecule adsorbed to its surface, exploring assumptions made in previous efforts to model WGM sensor behavior, and describing computational schemes that model the experiments for which single protein sensitivity was reported. The resulting model is used to simulate sensor performance, within constraints imposed by the limited material property data. On this basis, we conclude that nonlinear optical effects would be needed to attain the reported sensitivity, and that, in the experiments for which extreme sensitivity was reported, a bound protein experiences optical energy fluxes too high for such effects to be ignored.

  5. Mechanical energy dissipation induced by sloshing and wave breaking in a fully coupled angular motion system. II. Experimental investigation

    NASA Astrophysics Data System (ADS)

    Bouscasse, B.; Colagrossi, A.; Souto-Iglesias, A.; Cercos-Pita, J. L.

    2014-03-01

    In Paper I of this series [B. Bouscasse, A. Colagrossi, A. Souto-Iglesias, and J. L. C. Pita, "Mechanical energy dissipation induced by sloshing and wave breaking in a fully coupled angular motion system. I. Theoretical formulation and numerical investigation," Phys. Fluids 26, 033103 (2014)], a theoretical and numerical model for a driven pendulum filled with liquid was developed. The system was analyzed in the framework of tuned liquid dampers and hybrid mass liquid dampers (HMLD) theory. In this paper, in order to measure the energy dissipation resulting from shallow water sloshing, an experimental investigation is conducted. Accurate evaluations of energy transfers are obtained through the recorded kinematics of the system. A set of experiments is conducted with three different liquids: water, sunflower oil, and glycerine. Coherently with the results of Paper I, the energy dissipation obtained when the tank is filled with water can mainly be explained by the breaking waves. For all three liquids, the effects of varying the external excitation amplitude are discussed.

  6. Research on air sprays and unique foam application methods. Phase II report. Laboratory investigation of foam systems

    SciTech Connect

    Not Available

    1982-06-01

    The objective of this study is to assess the effectiveness of air sprays and foam systems for dust control on longwall double-drum shearer faces. Laboratory testing has been conducted using foam systems and promising results have been obtained. Upon Bureau approval, underground testing will be scheduled to assess the effectiveness of foam systems under actual operating conditions. Laboratory testing of air sprays is being conducted at present. This report presents the results of the laboratory testing of foam systems. Specifically, the results obtained on the evaluation of selected foaming agents are presented, the feasibility investigation of flushing foam through the shearer-drum are demonstrated, and conceptual layout of the foam system on the shearer is discussed. The laboratory investigation of the selected foaming agents reveal that the Onyx Microfoam, Onyx Maprosyl and DeTer Microfoam foaming agents have higher expansion ratios compared to the others tested. Flushing foam through the shearer drum is entirely feasible and could be a viable technique for dust suppression on longwall faces.

  7. Statistical investigation of simulated intestinal fluid composition on the equilibrium solubility of biopharmaceutics classification system class II drugs.

    PubMed

    Khadra, Ibrahim; Zhou, Zhou; Dunn, Claire; Wilson, Clive G; Halbert, Gavin

    2015-01-25

    A drug's solubility and dissolution behaviour within the gastrointestinal tract is a key property for successful administration by the oral route and one of the key factors in the biopharmaceutics classification system. This property can be determined by investigating drug solubility in human intestinal fluid (HIF) but this is difficult to obtain and highly variable, which has led to the development of multiple simulated intestinal fluid (SIF) recipes. Using a statistical design of experiment (DoE) technique this paper has investigated the effects and interactions on equilibrium drug solubility of seven typical SIF components (sodium taurocholate, lecithin, sodium phosphate, sodium chloride, pH, pancreatin and sodium oleate) within concentration ranges relevant to human intestinal fluid values. A range of poorly soluble drugs with acidic (naproxen, indomethacin, phenytoin, and piroxicam), basic (aprepitant, carvedilol, zafirlukast, tadalafil) or neutral (fenofibrate, griseofulvin, felodipine and probucol) properties have been investigated. The equilibrium solubility results determined are comparable with literature studies of the drugs in either HIF or SIF indicating that the DoE is operating in the correct space. With the exception of pancreatin, all of the factors individually had a statistically significant influence on equilibrium solubility with variations in magnitude of effect between the acidic and basic or neutral compounds and drug specific interactions were evident. Interestingly for the neutral compounds pH was the factor with the second largest solubility effect. Around one third of all the possible factor combinations showed a significant influence on equilibrium solubility with variations in interaction significance and magnitude of effect between the acidic and basic or neutral compounds. The least number of significant media component interactions were noted for the acidic compounds with three and the greatest for the neutral compounds at seven

  8. Year 6 Post-Remediation Biomonitoring and Phase II Source Investigation at the United Heckathorn Superfund Site, Richmond, California

    SciTech Connect

    Kohn, Nancy P.; Evans, Nathan R.

    2004-04-02

    The Heckathorn Superfund Site in Richmond, California, encompasses the property of the former United Heckathorn pesticide packaging plant and the adjacent waterway, Lauritzen Channel. The site was used from 1945 to 1966 by several operators to produce various agricultural chemicals. The site was placed on the National Priorities List of Superfund sites in 1990, which resulted in the removal of pesticide-contaminated soil from the upland portion of the site and dredging the marine portion of the site. Post-remediation marine monitoring and associated studies conducted through 2002 indicate that the contamination in the channel continues to pose a significant risk to biota and human health. This report documents continued marine monitoring and source investigation studies conducted in 2003.

  9. Dependence on the F0F1-ATP synthase for the activities of