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Sample records for non-conservative aminoacid substitutions

  1. Amino-acid substitution in alpha-spectrin commonly coinherited with nondominant hereditary spherocytosis.

    PubMed

    Tse, W T; Gallagher, P G; Jenkins, P B; Wang, Y; Benoit, L; Speicher, D; Winkelmann, J C; Agre, P; Forget, B G; Marchesi, S L

    1997-03-01

    Nondominant hereditary spherocytosis (ndHS) is a disorder characterized in some patients by severe hemolytic anemia and marked deficiency of erythrocyte spectrin. This report describes the identification of a variant spectrin chain, alpha-spectrin Bughill or alpha(BH), that is associated with this disorder in a number of patients. Tryptic maps of spectrin from affected individuals revealed an acidic shift in isoelectric point of the alphaII domain peptides at 46 kD and 35 kD. A point mutation at codon 970 of the alpha-spectrin gene (GCT-->GAT), that changes the encoded amino acid from an alanine to an aspartic acid, was identified in genomic DNA of affected patients. The alpha(BH) variant was present in 8 patients with ndHS from five different kindreds but was absent in 4 patients from two other kindreds. The 8 ndHS patients with the alpha(BH) variant appeared to be homozygous for the alpha(BH) variant by analysis of peptide maps of limited tryptic digests of erythrocyte spectrin. However, following genomic DNA analysis, only 2 of these patients were true homozygotes, whereas 6 were found to be doubly heterozygous for the alpha(BH) allele and a second, presumably abnormal, alpha-spectrin gene. These results suggest that, in these 6 patients, the second alpha-spectrin allele is in fact associated with one or more genetic defect(s), causing decreased accumulation of alpha-spectrin. The pattern of transmission of the alpha(BH) allele in certain families suggests that the alpha(BH) amino-acid substitution is not itself responsible for ndHS but is more likely a polymorphic variant that, in some but not all cases, is in linkage disequilibrium with another uncharacterized alpha-spectrin gene defect that itself is a cause of ndHS. PMID:9067503

  2. Greater efficiency of photosynthetic carbon fixation due to single amino-acid substitution

    PubMed Central

    Paulus, Judith Katharina; Schlieper, Daniel; Groth, Georg

    2013-01-01

    The C4-photosynthetic carbon cycle is an elaborated addition to the classical C3-photosynthetic pathway, which improves solar conversion efficiency. The key enzyme in this pathway, phosphoenolpyruvate carboxylase, has evolved from an ancestral non-photosynthetic C3 phosphoenolpyruvate carboxylase. During evolution, C4 phosphoenolpyruvate carboxylase has increased its kinetic efficiency and reduced its sensitivity towards the feedback inhibitors malate and aspartate. An open question is the molecular basis of the shift in inhibitor tolerance. Here we show that a single-point mutation is sufficient to account for the drastic differences between the inhibitor tolerances of C3 and C4 phosphoenolpyruvate carboxylases. We solved high-resolution X-ray crystal structures of a C3 phosphoenolpyruvate carboxylase and a closely related C4 phosphoenolpyruvate carboxylase. The comparison of both structures revealed that Arg884 supports tight inhibitor binding in the C3-type enzyme. In the C4 phosphoenolpyruvate carboxylase isoform, this arginine is replaced by glycine. The substitution reduces inhibitor affinity and enables the enzyme to participate in the C4 photosynthesis pathway. PMID:23443546

  3. Case-control studies show that a non-conservative amino-acid change from a glutamine to arginine in the P2RX7 purinergic receptor protein is associated with both bipolar- and unipolar-affective disorders.

    PubMed

    McQuillin, A; Bass, N J; Choudhury, K; Puri, V; Kosmin, M; Lawrence, J; Curtis, D; Gurling, H M D

    2009-06-01

    Three linkage studies of bipolar disorder have implicated chromosome 12q24.3 with lod scores of over 3.0 and several other linkage studies have found lods between 2 and 3. Fine mapping within the original chromosomal linkage regions has identified several loci that show association with bipolar disorder. One of these is the P2RX7 gene encoding a central nervous system-expressed purinergic receptor. A non-synonymous single nucleotide polymorphism, rs2230912 (P2RX7-E13A, G allele) and a microsatellite marker NBG6 were both previously found to be associated with bipolar disorder (P=0.00071 and 0.008, respectively). rs2230912 has also been found to show association with unipolar depression. The effect of the polymorphism is non-conservative and results in a glutamine to arginine change (Gln460Arg), which is likely to affect P2RX7 dimerization and protein-protein interactions. We have confirmed the allelic associations between bipolar disorder and the markers rs2230912 (P2RX7-E13A, G allele, P=0.043) and NBG6 (P=0.010) in a London-based sample of 604 bipolar cases and 560 controls. When we combined these data with the published case-control studies of P2RX7 and mood disorder (3586 individuals) the association between rs2230912 (Gln460Arg) and affective disorders became more robust (P=0.002). The increase in Gln460Arg was confined to heterozygotes rather than homozygotes suggesting a dominant effect (odds ratio 1.302, CI=1.129-1.503). Although further research is needed to prove that the Gln460Arg change has an aetiological role, it is so far the most convincing mutation to have been found with a role for increasing susceptibility to bipolar and genetically related unipolar disorders.

  4. Structural and Functional Characteristics of Oxysterol 7α-Hydroxylase with Amino-Acid Substitution R486C and Their Relation to the Appearance of Neurodegenerative Diseases

    NASA Astrophysics Data System (ADS)

    Dichenko, Ya. V.; Yantsevich, A. V.; Usanov, S. A.

    2015-03-01

    The influence of the amino-acid substitution Arg486Cys on the conformational stability of recombinant cytochrome P450 7B1 (CYP7B1, oxysterol 7α-hydroxylase) was studied. The single base change was shown to decrease the free energy of the transition of the heme-protein from its native state to a denatured one, which pointed to a lower thermodynamic stability for the mutant form of the enzyme. This could be the cause of the metabolic disruption of neurosteroids and, as a consequence, the appearance of neurodegenerative diseases.

  5. LASER BIOLOGY AND MEDICINE: Application of laser fluorimetry for determining the influence of a single amino-acid substitution on the individual photophysical parameters of a fluorescent form of a fluorescent protein mRFP1

    NASA Astrophysics Data System (ADS)

    Banishev, A. A.; Vrzheshch, E. P.; Shirshin, E. A.

    2009-03-01

    Individual photophysical parameters of the chromophore of a fluorescent protein mRFP1 and its two mutants (amino-acid substitution at position 66 - mRFP1/ Q66C and mRFP1/Q66S proteins) are determined. For this purpose, apart from conventional methods of fluorimetry and spectrophotometry, nonlinear laser fluorimetry is used. It is shown that the individual extinction coefficients of the chromophore of proteins correlate (correlation coefficient above 0.9) with the volume of the substituted amino-acid residue at position 66 (similar to the positions of the absorption, fluorescence excitation and emission maxima).

  6. Application of laser fluorimetry for determining the influence of a single amino-acid substitution on the individual photophysical parameters of a fluorescent form of a fluorescent protein mRFP1

    SciTech Connect

    Banishev, A A; Vrzheshch, E P; Shirshin, E A

    2009-03-31

    Individual photophysical parameters of the chromophore of a fluorescent protein mRFP1 and its two mutants (amino-acid substitution at position 66 - mRFP1/ Q66C and mRFP1/Q66S proteins) are determined. For this purpose, apart from conventional methods of fluorimetry and spectrophotometry, nonlinear laser fluorimetry is used. It is shown that the individual extinction coefficients of the chromophore of proteins correlate (correlation coefficient above 0.9) with the volume of the substituted amino-acid residue at position 66 (similar to the positions of the absorption, fluorescence excitation and emission maxima). (laser biology and medicine)

  7. A Single Amino-Acid Substitution in the Sodium Transporter HKT1 Associated with Plant Salt Tolerance.

    PubMed

    Ali, Akhtar; Raddatz, Natalia; Aman, Rashid; Kim, Songmi; Park, Hyeong Cheol; Jan, Masood; Baek, Dongwon; Khan, Irfan Ullah; Oh, Dong-Ha; Lee, Sang Yeol; Bressan, Ray A; Lee, Keun Woo; Maggio, Albino; Pardo, Jose M; Bohnert, Hans J; Yun, Dae-Jin

    2016-07-01

    A crucial prerequisite for plant growth and survival is the maintenance of potassium uptake, especially when high sodium surrounds the root zone. The Arabidopsis HIGH-AFFINITY K(+) TRANSPORTER1 (HKT1), and its homologs in other salt-sensitive dicots, contributes to salinity tolerance by removing Na(+) from the transpiration stream. However, TsHKT1;2, one of three HKT1 copies in Thellungiella salsuginea, a halophytic Arabidopsis relative, acts as a K(+) transporter in the presence of Na(+) in yeast (Saccharomyces cerevisiae). Amino-acid sequence comparisons indicated differences between TsHKT1;2 and most other published HKT1 sequences with respect to an Asp residue (D207) in the second pore-loop domain. Two additional T salsuginea and most other HKT1 sequences contain Asn (n) in this position. Wild-type TsHKT1;2 and altered AtHKT1 (AtHKT1(N-D)) complemented K(+)-uptake deficiency of yeast cells. Mutant hkt1-1 plants complemented with both AtHKT1(N) (-) (D) and TsHKT1;2 showed higher tolerance to salt stress than lines complemented by the wild-type AtHKT1 Electrophysiological analysis in Xenopus laevis oocytes confirmed the functional properties of these transporters and the differential selectivity for Na(+) and K(+) based on the n/d variance in the pore region. This change also dictated inward-rectification for Na(+) transport. Thus, the introduction of Asp, replacing Asn, in HKT1-type transporters established altered cation selectivity and uptake dynamics. We describe one way, based on a single change in a crucial protein that enabled some crucifer species to acquire improved salt tolerance, which over evolutionary time may have resulted in further changes that ultimately facilitated colonization of saline habitats.

  8. A Single Amino-Acid Substitution in the Sodium Transporter HKT1 Associated with Plant Salt Tolerance1[OPEN

    PubMed Central

    Ali, Akhtar; Aman, Rashid; Park, Hyeong Cheol; Jan, Masood; Baek, Dongwon; Khan, Irfan Ullah; Oh, Dong-Ha; Lee, Sang Yeol; Bressan, Ray A.; Lee, Keun Woo; Maggio, Albino; Yun, Dae-Jin

    2016-01-01

    A crucial prerequisite for plant growth and survival is the maintenance of potassium uptake, especially when high sodium surrounds the root zone. The Arabidopsis HIGH-AFFINITY K+ TRANSPORTER1 (HKT1), and its homologs in other salt-sensitive dicots, contributes to salinity tolerance by removing Na+ from the transpiration stream. However, TsHKT1;2, one of three HKT1 copies in Thellungiella salsuginea, a halophytic Arabidopsis relative, acts as a K+ transporter in the presence of Na+ in yeast (Saccharomyces cerevisiae). Amino-acid sequence comparisons indicated differences between TsHKT1;2 and most other published HKT1 sequences with respect to an Asp residue (D207) in the second pore-loop domain. Two additional T. salsuginea and most other HKT1 sequences contain Asn (n) in this position. Wild-type TsHKT1;2 and altered AtHKT1 (AtHKT1N-D) complemented K+-uptake deficiency of yeast cells. Mutant hkt1-1 plants complemented with both AtHKT1N-D and TsHKT1;2 showed higher tolerance to salt stress than lines complemented by the wild-type AtHKT1. Electrophysiological analysis in Xenopus laevis oocytes confirmed the functional properties of these transporters and the differential selectivity for Na+ and K+ based on the n/d variance in the pore region. This change also dictated inward-rectification for Na+ transport. Thus, the introduction of Asp, replacing Asn, in HKT1-type transporters established altered cation selectivity and uptake dynamics. We describe one way, based on a single change in a crucial protein that enabled some crucifer species to acquire improved salt tolerance, which over evolutionary time may have resulted in further changes that ultimately facilitated colonization of saline habitats. PMID:27208305

  9. A Single Amino-Acid Substitution in the Sodium Transporter HKT1 Associated with Plant Salt Tolerance.

    PubMed

    Ali, Akhtar; Raddatz, Natalia; Aman, Rashid; Kim, Songmi; Park, Hyeong Cheol; Jan, Masood; Baek, Dongwon; Khan, Irfan Ullah; Oh, Dong-Ha; Lee, Sang Yeol; Bressan, Ray A; Lee, Keun Woo; Maggio, Albino; Pardo, Jose M; Bohnert, Hans J; Yun, Dae-Jin

    2016-07-01

    A crucial prerequisite for plant growth and survival is the maintenance of potassium uptake, especially when high sodium surrounds the root zone. The Arabidopsis HIGH-AFFINITY K(+) TRANSPORTER1 (HKT1), and its homologs in other salt-sensitive dicots, contributes to salinity tolerance by removing Na(+) from the transpiration stream. However, TsHKT1;2, one of three HKT1 copies in Thellungiella salsuginea, a halophytic Arabidopsis relative, acts as a K(+) transporter in the presence of Na(+) in yeast (Saccharomyces cerevisiae). Amino-acid sequence comparisons indicated differences between TsHKT1;2 and most other published HKT1 sequences with respect to an Asp residue (D207) in the second pore-loop domain. Two additional T salsuginea and most other HKT1 sequences contain Asn (n) in this position. Wild-type TsHKT1;2 and altered AtHKT1 (AtHKT1(N-D)) complemented K(+)-uptake deficiency of yeast cells. Mutant hkt1-1 plants complemented with both AtHKT1(N) (-) (D) and TsHKT1;2 showed higher tolerance to salt stress than lines complemented by the wild-type AtHKT1 Electrophysiological analysis in Xenopus laevis oocytes confirmed the functional properties of these transporters and the differential selectivity for Na(+) and K(+) based on the n/d variance in the pore region. This change also dictated inward-rectification for Na(+) transport. Thus, the introduction of Asp, replacing Asn, in HKT1-type transporters established altered cation selectivity and uptake dynamics. We describe one way, based on a single change in a crucial protein that enabled some crucifer species to acquire improved salt tolerance, which over evolutionary time may have resulted in further changes that ultimately facilitated colonization of saline habitats. PMID:27208305

  10. A single amino-acid substitution toggles chloride dependence of the alpha-amylase paralog amyrel in Drosophila melanogaster and Drosophila virilis species.

    PubMed

    Claisse, Gaëlle; Feller, Georges; Bonneau, Magalie; Da Lage, Jean-Luc

    2016-08-01

    In animals, most α-amylases are chloride-dependent enzymes. A chloride ion is required for allosteric activation and is coordinated by one asparagine and two arginine side chains. Whereas the asparagine and one arginine are strictly conserved, the main chloride binding arginine is replaced by a glutamine in some rare instances, resulting in the loss of chloride binding and activation. Amyrel is a distant paralogue of α-amylase in Diptera, which was not characterized biochemically to date. Amyrel shows both substitutions depending on the species. In Drosophila melanogaster, an arginine is present in the sequence but in Drosophila virilis, a glutamine occurs at this position. We have investigated basic enzymological parameters and the dependence to chloride of Amyrel of both species, produced in yeast, and in mutants substituting arginine to glutamine or glutamine to arginine. We found that the amylolytic activity of Amyrel is about thirty times weaker than the classical Drosophila α-amylase, and that the substitution of the arginine by a glutamine in D. melanogaster suppressed the chloride-dependence but was detrimental to activity. In contrast, changing the glutamine into an arginine rendered D. virilis Amyrel chloride-dependent, and interestingly, significantly increased its catalytic efficiency. These results show that the chloride ion is not mandatory for Amyrel but stimulates the reaction rate. The possible phylogenetic origin of the arginine/glutamine substitution is also discussed. PMID:27312592

  11. Non-conservative mass transfers in Algols

    NASA Astrophysics Data System (ADS)

    Erdem, A.; Öztürk, O.

    2014-06-01

    We applied a revised model for non-conservative mass transfer in semi-detached binaries to 18 Algol-type binaries showing orbital period increase or decrease in their parabolic O-C diagrams. The combined effect of mass transfer and magnetic braking due to stellar wind was considered when interpreting the orbital period changes of these 18 Algols. Mass transfer was found to be the dominant mechanism for the increase in orbital period of 10 Algols (AM Aur, RX Cas, DK Peg, RV Per, WX Sgr, RZ Sct, BS Sct, W Ser, BD Vir, XZ Vul) while magnetic braking appears to be the responsible mechanism for the decrease in that of 8 Algols (FK Aql, S Cnc, RU Cnc, TU Cnc, SX Cas, TW Cas, V548 Cyg, RY Gem). The peculiar behaviour of orbital period changes in three W Ser-type binary systems (W Ser, itself a prototype, RX Cas and SX Cas) is discussed. The empirical linear relation between orbital period (P) and its rate of change (dP/dt) was also revised.

  12. Tailoring GalNAcα1-3Galβ-specific lectins from a multi-specific fungal galectin: dramatic change of carbohydrate specificity by a single amino-acid substitution.

    PubMed

    Hu, Dan; Tateno, Hiroaki; Sato, Takashi; Narimatsu, Hisashi; Hirabayashi, Jun

    2013-07-15

    Galectins exhibit multiple roles through recognition of diverse structures of β-galactosides. However, this broad specificity often hinders their practical use as probes. In the present study we report a dramatic improvement in the carbohydrate specificity of a multi-specific fungal galectin from the mushroom Agrocybe cylindricea, which binds not only to simple β-galactosides, but also to their derivatives. Site-directed mutagenesis targeting five residues involved in β-galactose binding revealed that replacement of Asn46 with alanine (N46A) increased the binding to GalNAcα1-3Galβ-containing glycans, while eliminating binding to all other β-galactosides, as shown by glycoconjugate microarray analysis. Quantitative analysis by frontal affinity chromatography showed that the mutant N46A had enhanced affinity towards blood group A tetraose (type 2), A hexaose (type 1) and Forssman pentasaccharide with dissociation constants of 5.0 × 10⁻⁶ M, 3.8 × 10⁻⁶ M and 1.0 × 10⁻⁵ M respectively. Surprisingly, all the other mutants generated by saturation mutagenesis of Asn46 exhibited essentially the same specificity as N46A. Moreover, alanine substitution for Pro45, which forms the cis-conformation upon β-galactose binding, exhibited the same specificity as N46A. From a practical viewpoint, the derived N46A mutant proved to be unique as a specific probe to detect GalNAcα1-3Galβ-containing glycans by methods such as flow cytometry, cell staining and lectin microarray.

  13. Amino-acid contamination of aqueous hydrochloric acid.

    NASA Technical Reports Server (NTRS)

    Wolman, Y.; Miller, S. L.

    1971-01-01

    Considerable amino-acid contamination in commercially available analytical grade hydrochloric acid (37% HCl) was found. One bottle contained 8,300 nmol of amino-acids per liter. A bottle from another supplier contained 6,700 nmol per liter. The contaminants were mostly protein amino-acids and several unknowns. Data on the volatility of the amino-acids during HCl distillation were also obtained.

  14. Radiation reaction as a non-conservative force

    NASA Astrophysics Data System (ADS)

    Aashish, Sandeep; Haque, Asrarul

    2016-09-01

    We study a system of a finite size charged particle interacting with a radiation field by exploiting Hamilton’s principle for a non-conservative system recently introduced by Galley [1]. This formulation leads to the equation of motion of the charged particle that turns out to be the same as that obtained by Jackson [2]. We show that the radiation reaction stems from the non-conservative part of the effective action for a charged particle. We notice that a charge interacting with a radiation field modeled as a heat bath affords a way to justify that the radiation reaction is a non-conservative force. The topic is suitable for graduate courses on advanced electrodynamics and classical theory of fields.

  15. B Non-Conservation, Cold Dark Matter and Subpreon Model

    NASA Astrophysics Data System (ADS)

    Senju, H.

    1990-06-01

    In our model a weakly-interacting massive particle l_{s}(e) exists. The consideration of baryon number non-conserving processes which are assumed to originate in the subpreon physics shows an asymmetrical existence of it in the universe. Using the formalism of Griest and Seckel, it is shown that l_{s}(e) is a viable candidate of the cold dark matter.

  16. Helicity non-conserving form factor of the proton

    SciTech Connect

    Voutier, E.; Furget, C.; Knox, S.

    1994-04-01

    The study of the hadron structure in the high Q{sup 2} range contributes to the understanding of the mechanisms responsible for the confinement of quarks and gluons. Among the numerous experimental candidates sensitive to these mechanisms, the helicity non-conserving form factor of the proton is a privileged observable since it is controlled by non-perturbative effects. The authors investigate here the feasibility of high Q{sup 2} measurements of this form factor by means of the recoil polarization method in the context of the CEBAF 8 GeV facility. For that purpose, they discuss the development of a high energy proton polarimeter, based on the H({rvec p},pp) elastic scattering, to be placed at the focal plane of a new hadron spectrometer. It is shown that this experimental method significantly improves the knowledge of the helicity non-conserving form factor of the proton up to 10 GeV{sup 2}/c{sup 2}.

  17. Non-conservative perturbations of homoclinic snaking scenarios

    NASA Astrophysics Data System (ADS)

    Knobloch, Jürgen; Vielitz, Martin

    2016-01-01

    Homoclinic snaking refers to the continuation of homoclinic orbits to an equilibrium E near a heteroclinic cycle connecting E and a periodic orbit P. Typically homoclinic snaking appears in one-parameter families of reversible, conservative systems. Here we discuss perturbations of this scenario which are both non-reversible and non-conservative. We treat this problem analytically in the spirit of the work [3]. The continuation of homoclinic orbits happens with respect to both the original continuation parameter μ and the perturbation parameter λ. The continuation curves are parametrised by the dwelling time L of the homoclinic orbit near P. It turns out that λ (L) tends to zero while the μ vs. L diagram displays isolas or criss-cross snaking curves in a neighbourhood of the original snakes-and-ladder structure. In the course of our studies we adapt both Fenichel coordinates near P and the analysis of Shilnikov problems near P to the present situation.

  18. Non-conservative optical forces and Brownian vortexes

    NASA Astrophysics Data System (ADS)

    Sun, Bo

    Optical manipulation using optical tweezers has been widely adopted in physics, chemical engineering and biology. While most applications and fundamental studies of optical trapping have focused on optical forces resulting from intensity gradients, we have also explored the role of radiation pressure, which is directed by phase gradients in beams of light. Interestingly, radiation pressure turns out to be a non-conservative force and drives trapped objects out of thermodynamic equilibrium with their surrounding media. We have demonstrated the resulting nonequilibrium effects experimentally by tracking the thermally driven motions of optically trapped colloidal spheres using holographic video microscopy. Rather than undergoing equilibrium thermal fluctuations, as has been assumed for more than a quarter century, a sphere in an optical tweezer enters into a stochastic steady-state characterized by closed loops in its probability current density. These toroidal vortexes constitute a bias in the particle's otherwise random thermal fluctuations arising at least indirectly from a solenoidal component in the optical force. This surprising effect is a particular manifestation of a more general class of noise-driven machines that we call Brownian vortexes. This previously unrecognized class of stochastic heat engines operates on qualitatively different principles from such extensively studied nonequilibrium systems as thermal ratchets and Brownian motors. Among its interesting properties, a Brownian vortex can reverse its direction with changes in temperature or equivalent control parameters.

  19. Non-conservative evolution in Algols: where is the matter?

    NASA Astrophysics Data System (ADS)

    Deschamps, R.; Braun, K.; Jorissen, A.; Siess, L.; Baes, M.; Camps, P.

    2015-05-01

    Context. There is indirect evidence of non-conservative evolutions in Algols. However, the systemic mass-loss rate is poorly constrained by observations and generally set as a free parameter in binary-star evolution simulations. Moreover, systemic mass loss may lead to observational signatures that still need to be found. Aims: Within the "hotspot" ejection mechanism, some of the material that is initially transferred from the companion star via an accretion stream is expelled from the system due to the radiative energy released on the gainer's surface by the impacting material. The objective of this paper is to retrieve observable quantities from this process and to compare them with observations. Methods: We investigate the impact of the outflowing gas and the possible presence of dust grains on the spectral energy distribution (SED). We used the 1D plasma code Cloudy and compared the results with the 3D Monte-Carlo radiative transfer code Skirt for dusty simulations. The circumbinary mass-distribution and binary parameters were computed with state-of-the-art binary calculations done with the Binstar evolution code. Results: The outflowing material reduces the continuum flux level of the stellar SED in the optical and UV. Because of the time-dependence of this effect, it may help to distinguish between different ejection mechanisms. If present, dust leads to observable infrared excesses, even with low dust-to-gas ratios, and traces the cold material at large distances from the star. By searching for this dust emission in the WISE catalogue, we found a small number of Algols showing infrared excesses, among which the two rather surprising objects SX Aur and CZ Vel. We find that some binary B[e] stars show the same strong Balmer continuum as we predict with our models. However, direct evidence of systemic mass loss is probably not observable in genuine Algols, since these systems no longer eject mass through the hotspot mechanism. Furthermore, owing to its high

  20. Purification of a marsupial insulin: amino-acid sequence of insulin from the eastern grey kangaroo Macropus giganteus.

    PubMed

    Treacy, G B; Shaw, D C; Griffiths, M E; Jeffrey, P D

    1989-03-24

    Insulin has been purified from kangaroo pancreas by acidic ethanol extraction, diethyl ether precipitation and gel filtration. The amino-acid sequence of this, the first marsupial insulin to be studied, is reported. It differs from human insulin by only four amino-acid substitutions, all in regions of the molecule previously known to be variable. However, it should be noted that one of these, asparagine for threonine at A8, has not been reported before. Computer comparisons of all 43 insulin sequences reported to date with kangaroo insulin show it to be most closely related to a group of mammalian insulins (dog, pig, cow, human) known to be of high biological potency. The measurement of blood glucose lowering in the rabbit by kangaroo insulin is consistent with this conclusion. Comparisons of amino-acid sequences of other proteins with their kangaroo counterparts show a greater difference, in line with the time of divergence of marsupials. The limited differences observed in insulin and cytochrome c suggest that their structures need to be closely conserved in order to maintain function.

  1. The chlorinating behaviour of WCl₆ towards α-aminoacids.

    PubMed

    Bortoluzzi, Marco; Marchetti, Fabio; Murrali, Maria Grazia; Pampaloni, Guido; Zacchini, Stefano

    2015-05-14

    Cl/O interchange took place when WCl6 was allowed to interact with a series of α-aminoacids. The α-ammonium-acylchloride salts [NH2(CH2)3CHC(O)Cl][WOCl5], 1a, and [MeNH2CH2C(O)Cl][WOCl5], 1b, were afforded in ca. 55% yields from the reactions of WCl6 with, respectively, L-proline and sarcosine in CH2Cl2. By using other reaction media (hexane or CHCl3), the α-amino-acylchloride complexes WOCl4[O=C(Cl)CH(CH2)3NH2], 5a, and WOCl4[O=C(Cl)CH(R)NHR'] (R = H, R' = Me, 5b; R = R' = H, 5c; R = Me, R' = H, 5d) were isolated in moderate to good yields from WCl6 and, respectively, L-proline, sarcosine, glycine and L-alanine. The formation of 5a,b is basically the result of HCl release from the parent compounds 1a,b. 5a represents a key intermediate in the course of the reaction leading to (WOCl4)2[μ:κ(2)(O)-dkp], 2, dkp = (S,S)-octahydrodipyrrolo[1,2-a:1',2'-d]pyrazine-5,10-dione. 2 was optimally prepared from WCl6/L-proline under high temperature conditions. Hydrolytic treatment of 2 afforded the L-proline-derived 2,5-diketopiperazine (dkp), which was finally isolated with an overall yield of 70%. 1a,b were characterized by X-ray diffractometry, thus providing very rare examples of crystallographically characterized acylchloride derivatives of α-aminoacids. DFT calculations were extensively carried out in order to shed light on structural and mechanistic features.

  2. Amino-acid residues involved in the expression of the activity of Escherichia coli TolC.

    PubMed

    Yamanaka, Hiroyasu; Morisada, Naoyuki; Miyano, Masaya; Tsuge, Hideaki; Shinoda, Sumio; Takahashi, Eizo; Okamoto, Keinosuke

    2004-01-01

    The Escherichia coli TolC, composed of 471 amino-acid residues, functions as a channel tunnel in the transport of various molecules across the outer membrane. We found previously that Leu-412, the 60th amino-acid residue from the carboxy terminal end, was crucial to the transport activity of TolC. Leu-412 is located in a domain which protrudes from the main body of TolC into the periplasm. Subsequent study indicated that the hydrophobicity generated by Leu-412 played an important role in the activity of TolC (H. Yamanaka, T. Nomura, N. Morisada, S. Shinoda, and K. Okamoto, Microb. Pathog. 33: 81-89, 2002). We predicted that other hydrophobic amino-acid residues around Leu-412 were also involved in the expression of the activity of TolC. To test this possibility, we substituted several hydrophobic residues around Leu-412, (Leu-3, Val-6, Leu-212, Leu-213, Leu-223, and Leu-224), with serine and examined the activity of these mutant TolCs. The result showed that Leu-3 is involved in the activity of TolC, but the other residues are not. The involvement of Leu-3 was confirmed by the residue deletion experiment. A subsequent point-mutational analysis of the residue showed that a hydrophobic side chain is required at position 3 for TolC to express its activity. As the distance between the alpha-carbons of Leu-3 and Leu-412 is just 7.45 angstroms, hydrophobic interaction between the two leucine residues might be involved in the activity of TolC. PMID:15502403

  3. Inhomogeneous atmospheres - On transforming conservative multiple scattering to non-conservative multiple pseudo-scattering

    NASA Astrophysics Data System (ADS)

    Domke, H.

    2016-11-01

    The F- and K-integrals are used to transform the zeroth azimuthal Fourier component of the radiative transfer equation for conservative multiple scattering of polarized light in vertically inhomogeneous plane atmospheres into an equivalent transfer equation with a modified phase matrix corresponding to non-conservative pseudo-scattering. With symmetry properties of the original phase matrix to be retained, the modification generally includes two arbitrary scalar functions depending on optical depth. It is shown that the surface Green's function matrices for conservative scattering can be expressed in terms of surface Green's function matrices for non-conservative pseudo-scattering. Linear constraints are obtained for surface Green's functions for conservative scattering as well as for particular forms of non-conservative pseudo-scattering. Explicit formulae are derived for retrieving the solutions of standard problems like diffuse reflection and transmission, and also for Milne's problem, for conservative inhomogeneous atmospheres by means of appropriate solutions for non-conservative multiple pseudo-scattering. Numerical experiments performed by solving the nonlinear integral equations for the diffuse reflection functions of homogeneous semi-infinite atmospheres demonstrate that an acceleration of iterations by orders of magnitude can be achieved when the transformation to equivalent multiple pseudo-scattering is applied.

  4. Review on hydroxylamine, a precursor to amino-acids

    NASA Astrophysics Data System (ADS)

    Lemaire, Jean Louis

    2015-08-01

    Does life on earth come from interstellar space (IS)?It has been recently demonstrated that part of the terrestrial water is of IS origin [Cleeves et al. Science 2014]. This raises the question whether materials like amino-acids or their pre-biotic molecular precursors could have been formed and brought to earth in the same way than water. Another question is whether these molecules were formed in the gas phase or through reactions on the surface/volume of ice-covered grains. This may then have occurred in the vicinity of proto-stellar cores or deep into a pristine dense molecular clouds at very low temperatures.As far as bio-related molecules are concerned, chemistry with nitrogen-bearing molecules (like NH3 and NO) is involved. I review recent experimental work showing that hydroxylamine (NH2OH) could be formed either by surface or by volume reactions in conditions close to those prevailing in dense media. They use either electron-UV irradiation of water-ammonia ices [Zheng & Kaiser JCPA 2010] or successive hydrogenation of solid nitric oxide[Congiu, Fedoseev & al. ApJL.2012] or the simple oxidation of ammonia [He, Vidali, Lemaire & Garrod, ApJ, 2015] or the reaction of ammonia with hydroxyl radicals in a rare gas matrix [Zins & Krim, 2014, 69th ISMS]. A step further, the synthesis of the simplest amino-acids, glycine (NH2CH2COOH) and L- or D-alanine (NH2CH3CHCOOH) has already been obtained via reactions in the gas phase involving NH2OH+ [Blagojevic & al. MNRAS 2003].In addition to several earlier models demonstrating that the formation of all these molecules is possible in the gas phase, a new recent three-phase gas-grain chemical kinetics model of hot cores [Garrod ApJ 2013] shows that the results of ammonia oxidation we obtain are plausible by surface/volume reactions.Although none of the aforementioned molecules (except glycine in a sample of cometary origin) has been yet detected in the IS, they all are considered by many observers and modelers as likely

  5. An uncertainty inclusive un-mixing model to identify tracer non-conservativeness

    NASA Astrophysics Data System (ADS)

    Sherriff, Sophie; Rowan, John; Franks, Stewart; Fenton, Owen; Jordan, Phil; hUallacháin, Daire Ó.

    2015-04-01

    Sediment fingerprinting is being increasingly recognised as an essential tool for catchment soil and water management. Selected physico-chemical properties (tracers) of soils and river sediments are used in a statistically-based 'un-mixing' model to apportion sediment delivered to the catchment outlet (target) to its upstream sediment sources. Development of uncertainty-inclusive approaches, taking into account uncertainties in the sampling, measurement and statistical un-mixing, are improving the robustness of results. However, methodological challenges remain including issues of particle size and organic matter selectivity and non-conservative behaviour of tracers - relating to biogeochemical transformations along the transport pathway. This study builds on our earlier uncertainty-inclusive approach (FR2000) to detect and assess the impact of tracer non-conservativeness using synthetic data before applying these lessons to new field data from Ireland. Un-mixing was conducted on 'pristine' and 'corrupted' synthetic datasets containing three to fifty tracers (in the corrupted dataset one target tracer value was manually corrupted to replicate non-conservative behaviour). Additionally, a smaller corrupted dataset was un-mixed using a permutation version of the algorithm. Field data was collected in an 11 km2 river catchment in Ireland. Source samples were collected from topsoils, subsoils, channel banks, open field drains, damaged road verges and farm tracks. Target samples were collected using time integrated suspended sediment samplers at the catchment outlet at 6-12 week intervals from July 2012 to June 2013. Samples were dried (<40°C), sieved (125 µm) and analysed for mineral magnetic susceptibility, anhysteretic remanence and iso-thermal remanence, and geochemical elements Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn (following microwave-assisted acid digestion). Discriminant analysis was used to reduce the number of tracer numbers before un-mixing. Tracer non-conservativeness

  6. Increased intestinal amino-acid retention from the addition of carbohydrates to a meal.

    PubMed

    Deutz, N E; Ten Have, G A; Soeters, P B; Moughan, P J

    1995-12-01

    Carbohydrates, added to a protein meal, are known to enhance the efficiency of dietary protein utilisation. However, the respective roles of the gut and liver in relation to this enhanced efficiency are not known. Therefore, we studied amino-acid, ammonia, urea, glucose and lactate fluxes for 6 h across the portal drained viscera and liver in conscious, multi-catheterised pigs of approximately 25 kg body weight after receiving a protein meal with added carbohydrates, a pure protein meal or a control meal. Additional carbohydrate caused a net glucose efflux in the portal drained viscera and increased arterial blood insulin levels. The appearance of amino-acids in the portal blood declined by some 30%, in spite of the dietary true amino-acid digestibility being approximately 95%. Liver uptake of most amino-acids was lower and there was a lower liver urea production. Finally, there was a smaller postprandial increase in the arterial blood concentration for most of the amino-acids. The results of this study suggest that inclusion of maltodextrin in the diet increases the net retention of meal-derived amino-acids in the portal drained viscera. The lower urea production and liver amino-acid uptake suggest a lower nitrogen loss. The gut could be an important site for nitrogen retention induced by the addition of carbohydrates to a protein meal.

  7. Family number non-conservation induced by the supersymmetric mixing of scalar leptons

    SciTech Connect

    Levine, M.J.S.

    1987-08-01

    The most egregious aspect of (N = 1) supersymmetric theories is that each particle state is accompanied by a 'super-partner', a state with identical quantum numbers save that it differs in spin by one half unit. For the leptons these are scalars and are called ''sleptons'', or scalar leptons. These consist of the charged sleptons (selectron, smuon, stau) and the scalar neutrinos ('sneutrinos'). We examine a model of supersymmetry with soft breaking terms in the electroweak sector. Explicit mixing among the scalar leptons results in a number of effects, principally non-conservation of lepton family number. Comparison with experiment permits us to place constraints upon the model. 49 refs., 12 figs.

  8. Parameters of proteome evolution from histograms of amino-acid sequence identities of paralogous proteins

    PubMed Central

    Axelsen, Jacob Bock; Yan, Koon-Kiu; Maslov, Sergei

    2007-01-01

    Background The evolution of the full repertoire of proteins encoded in a given genome is mostly driven by gene duplications, deletions, and sequence modifications of existing proteins. Indirect information about relative rates and other intrinsic parameters of these three basic processes is contained in the proteome-wide distribution of sequence identities of pairs of paralogous proteins. Results We introduce a simple mathematical framework based on a stochastic birth-and-death model that allows one to extract some of this information and apply it to the set of all pairs of paralogous proteins in H. pylori, E. coli, S. cerevisiae, C. elegans, D. melanogaster, and H. sapiens. It was found that the histogram of sequence identities p generated by an all-to-all alignment of all protein sequences encoded in a genome is well fitted with a power-law form ~ p-γ with the value of the exponent γ around 4 for the majority of organisms used in this study. This implies that the intra-protein variability of substitution rates is best described by the Gamma-distribution with the exponent α ≈ 0.33. Different features of the shape of such histograms allow us to quantify the ratio between the genome-wide average deletion/duplication rates and the amino-acid substitution rate. Conclusion We separately measure the short-term ("raw") duplication and deletion rates rdup∗, rdel∗ which include gene copies that will be removed soon after the duplication event and their dramatically reduced long-term counterparts rdup, rdel. High deletion rate among recently duplicated proteins is consistent with a scenario in which they didn't have enough time to significantly change their functional roles and thus are to a large degree disposable. Systematic trends of each of the four duplication/deletion rates with the total number of genes in the genome were analyzed. All but the deletion rate of recent duplicates rdel∗ were shown to systematically increase with Ngenes. Abnormally flat shapes

  9. Spectroscopy with Laser-cooled Francium and Progress on Atomic Parity Non-conservation

    NASA Astrophysics Data System (ADS)

    Zhang, Jiehang

    Francium, the heaviest alkali, possesses a unique combination of structural simplicity and great sensitivity to effects such as atomic parity non-conservation (APNC). We report in this thesis our progress towards measuring weak-interaction physics in a low energy system: the francium atom. We have built a new generation of high-efficiency laser cooling and trapping facility at TRIUMF national laboratory in Canada. We constructed a precision science chamber and demonstrate francium atom transfer into the precision trap, where the electromagnetic field environments can be exquisitely controlled such that weak-interaction studies via optical and microwave excitations can take place. We perform laser spectroscopy measurements of the hyperfine structure and isotope shifts in a chain of francium isotopes near the neutron closed shell (N = 126), including both ground and isomeric nuclear states. These measurements provide a basis for benchmarking state of the art atomic theory, as well as future nuclear structure calculations in Fr, necessary for interpreting the weak-interaction studies. These developments lay important foundations for precision parity non-conservation measurements with francium.

  10. The amino-acid sequence of kangaroo pancreatic ribonuclease.

    PubMed

    Gaastra, W; Welling, G W; Beintema, J J

    1978-05-01

    Red kangaroo (Macropus rufus) ribonuclease was isolated from pancreatic tissue by affinity chromatography. The amino acid sequence was determined by automatic sequencing of overlapping large fragments and by analysis of shorter peptides obtained by digestion with a number of proteolytic enzymes. The polypeptide chain consists of 122 amino acid residues. Compared to other ribonucleases, the N-terminal residue and residue 114 are deleted. In other pancreatic ribonucleases position 114 is occupied by a cis proline residue in an external loop at the surface of the molecule. Other remarkable substitutions are the presence of a tyrosine residue at position 123 instead of a serine which forms a hydrogen bond with the pyrimidine ring of a nucleotide substrate, and a number of hydrophobichydrophilic interchanges in the sequence 51-55, which forms part of an alpha-helix in bovine ribonuclease and exhibits few substitutions in the placental mammals. Kangaroo ribonuclease contains no carbohydrate, although the enzyme possesses a recognition site for carbohydrate attachment in the sequence Asn-Val-Thr (62-64). The enzyme differs at about 35-40% of the positions from all other mammalian pancreatic ribonucleases sequenced to date, which is in agreement with the early divergence between the marsupials and the placental mammals. From fragmentary data a tentative sequence of red-necked wallaby (Macropus rufogriseus) pancreatic ribonuclease has been derived. Eight differences with the kangaroo sequence were found.

  11. The amino-acid sequence of kangaroo pancreatic ribonuclease.

    PubMed

    Gaastra, W; Welling, G W; Beintema, J J

    1978-05-01

    Red kangaroo (Macropus rufus) ribonuclease was isolated from pancreatic tissue by affinity chromatography. The amino acid sequence was determined by automatic sequencing of overlapping large fragments and by analysis of shorter peptides obtained by digestion with a number of proteolytic enzymes. The polypeptide chain consists of 122 amino acid residues. Compared to other ribonucleases, the N-terminal residue and residue 114 are deleted. In other pancreatic ribonucleases position 114 is occupied by a cis proline residue in an external loop at the surface of the molecule. Other remarkable substitutions are the presence of a tyrosine residue at position 123 instead of a serine which forms a hydrogen bond with the pyrimidine ring of a nucleotide substrate, and a number of hydrophobichydrophilic interchanges in the sequence 51-55, which forms part of an alpha-helix in bovine ribonuclease and exhibits few substitutions in the placental mammals. Kangaroo ribonuclease contains no carbohydrate, although the enzyme possesses a recognition site for carbohydrate attachment in the sequence Asn-Val-Thr (62-64). The enzyme differs at about 35-40% of the positions from all other mammalian pancreatic ribonucleases sequenced to date, which is in agreement with the early divergence between the marsupials and the placental mammals. From fragmentary data a tentative sequence of red-necked wallaby (Macropus rufogriseus) pancreatic ribonuclease has been derived. Eight differences with the kangaroo sequence were found. PMID:658039

  12. Effects of amino-acid mixtures on food utilization and growth in Tenebrio molitor L.

    PubMed

    Davis, G R

    1985-06-01

    Ten holidic diets, varying in amino-acid concentration or composition, were fed to larvae of Tenebrio molitor for four weeks at 27 +/- 0.25 degrees C and 65 +/- 5% r.h. Effects of diet on growth, food utilization and energy utilization were recorded for individual larvae. Differences in gains in fresh weight or in dry matter among larvae fed diets containing 0% to 5% of the amino-acid mixture were not demonstrated. However, larvae fed 10% or 20% of this mixture gained more than the former, but less than larvae fed a diet of ground whole wheat and brewer's yeast (9:1, w/w). When the amino-acid mixture was supplemented with alanine, aspartic acid, and serine, or with these three and asparagine, and was fed to larvae at the 10% level, growth was slower than with the unsupplemented mixture. Supplementation of the amino-acid mixture with the first three amino acids did not reduce larval growth when fed at the 20% level. Amounts of food and of energy utilized were positively correlated with larval fresh-weight and dry-matter gains. Energy utilization was negatively correlated with dietary amino-acid level. Food and energy utilization and larval growth were influenced by dietary amino acids, either metabolically or through phagostimulation.

  13. The FrPNC experiment at TRIUMF: Atomic parity non-conservation in francium

    NASA Astrophysics Data System (ADS)

    Aubin, S.; Gomez, E.; Behr, J. A.; Pearson, M. R.; Sheng, D.; Zhang, J.; Collister, R.; Melconian, D.; Flambaum, V. V.; Sprouse, G. D.; Orozco, L. A.; Gwinner, G.

    2012-09-01

    The FrPNC collaboration has begun the construction of an on-line laser cooling and trapping apparatus at TRIUMF to measure atomic parity non-conservation (PNC) and the nuclear anapole moment in a string of artificially produced francium isotopes. Atomic PNC experiments provide unique high precision tests of the electroweak sector of the Standard Model at very low energies. Furthermore, precision measurements of spin-dependent atomic PNC can determine nuclear anapole moments and probe the weak force within the nucleus. Francium is an excellent candidate for precision measurements of atomic PNC due to its simple electronic structure and enhanced parity violation: both the optical PNC and anapole moment signals are expected to be over an order of magnitude larger than in cesium.

  14. Tracking channel-floodplain sediment exchange with conservative and non-conservative geochemical tracers

    NASA Astrophysics Data System (ADS)

    Belmont, Patrick; Stout, Justin

    2013-04-01

    Fine sediment is routed through landscapes and channel networks in a highly unsteady and non-uniform manner, potentially experiencing deposition and re-suspension many times during transport from source to sink. Developing a better understanding of sediment routing at the landscape scale is an intriguing challenge from a modeling perspective because it requires consideration of a multitude of processes that interact and vary in space and time. From an applied perspective, an improved understanding of sediment routing is essential for predicting how conservation and restoration practices within a watershed will influence water quality, to support land and water management decisions. Two key uncertainties in predicting sediment routing at the landscape scale are 1) determining the proportion of suspended sediment that is derived from terrestrial (soil) erosion versus channel (bank) erosion, and 2) constraining the proportion of sediment that is temporarily stored and re-suspended within the channel-floodplain complex. Sediment fingerprinting that utilizes a suite of conservative and non-conservative geochemical tracers associated with suspended sediment can provide insight regarding both of these key uncertainties. Here we present a model that tracks suspended sediment with associated conservative and non-conservative geochemical tracers. The model assumes that particle residence times are described by a bimodal distribution wherein some fraction of sediment is transported through the system in a relatively short time (< 1 year) and the remainder experiences temporary storage (of variable duration) within the channel-floodplain complex. We use the model to explore the downstream evolution of non-conservative tracers under equilibrium conditions (i.e., exchange between the channel and floodplain is allowed, but no net change in channel-floodplain storage can occur) to illustrate how the process of channel-floodplain storage and re-suspension can potentially bias

  15. Non-Conservation of Transverse Magnetization in Spin Diffusion in Trapped Boltzmann Gases

    SciTech Connect

    Ragan, R. J.; Mullin, W. J.

    2006-09-07

    Experiments in a mixture of two hyperfine states of trapped Bose gases show behavior analogous to a spin-1/2 system, including transverse spin waves and other familiar Leggett-Rice-type effects. We have derived the kinetic equations applicable to these systems, including the spin dependence of interparticle interactions in the collision integral. We find that the hydrodynamic diffusive modes cease to exist because interactions with different scattering lengths for up-up, up-down, and down-down spins lead to a spin-spin relaxation, that causes non-conservation of transverse magnetization. We give results for the quadrupole modes, the modes studied in experiments with equal scattering lengths. Instead of a linear dependence on relaxation time {tau} for the diffusive mode, we find a divergence at small {tau}. No such effect occurs in Fermi gases.

  16. Bidimensional nano-optomechanics and topological backaction in a non-conservative radiation force field.

    PubMed

    Gloppe, A; Verlot, P; Dupont-Ferrier, E; Siria, A; Poncharal, P; Bachelier, G; Vincent, P; Arcizet, O

    2014-11-01

    Optomechanics, which explores the fundamental coupling between light and mechanical motion, has made important advances in manipulating macroscopic mechanical oscillators down to the quantum level. However, dynamical effects related to the vectorial nature of the optomechanical interaction remain to be investigated. Here we study a nanowire with subwavelength dimensions coupled strongly to a tightly focused beam of light, enabling an ultrasensitive readout of the nanoresonator dynamics. We determine experimentally the vectorial structure of the optomechanical interaction and demonstrate that a bidimensional dynamical backaction governs the nanowire dynamics. Moreover, the spatial topology of the optomechanical interaction is responsible for novel canonical signatures of strong coupling between mechanical modes, which leads to a topological instability that underlies the non-conservative nature of the optomechanical interaction. These results have a universal character and illustrate the increased sensitivity of nanomechanical devices towards spatially varying interactions, opening fundamental perspectives in nanomechanics, optomechanics, ultrasensitive scanning force microscopy and nano-optics.

  17. Self-organization through dissipation in a non-conservative cellular-automaton model of earthquakes

    NASA Astrophysics Data System (ADS)

    Al-Kindy, F. H.; Main, I. G.

    2003-04-01

    Self-organizing systems are of particular interest from a thermodynamic perspective since they show the spontaneous emergence of pattern or order, in apparent contradiction of the second law of thermodynamics. Here we investigate self-organization in a non-conservative version of the Bak and Tang (BT) cellular-automaton model, and its dependence on dissipation for populations of synthetic earthquakes. The probability distributions of strain energy and radiated energy are used to calculate Shannon entropy S as a measure of disorder. As the conservation parameter α is decreased, the external entropy Se decreases as the internal entropy Si increases with Δ Se>0. This suggests that in the model, self-organization occurs at the expense of lowering the internal energy of the system through dissipation while increasing its entropy production globally. The results also show some similarities with recent analysis of real earthquake populations.

  18. Non-conservative evolution in short-period interacting binaries with the BINSTAR code

    NASA Astrophysics Data System (ADS)

    Deschamps, Romain; Siess, Lionel; Braun, Killian; Jorissen, Alain; Davis, Philip

    2014-09-01

    Systemic mass loss in interacting binaries such as of the Algol type has been inferred since the 1950s. There is indeed gathering indirect evidence indicating that some Algols follow non-conservative evolution, but still no direct detection of large mass outflows. As a result, little is known about the eventual ejection mechanism, the total amount of mass ejected or the specific angular momentum carried with this outflow. In order to reconcile stellar models and observations, we compute Algol models with the state-of-the-art binary star evolution code BINSTAR. We investigate systemic mass losses within the hotspot paradigm, where large outflows of material form from the accretion impact during the mass transfer phase. We then study the impact of this outflow on the spectral emission distribution of the system with the radiative transfer codes CLOUDY and SKIRT.

  19. Non-conservative GNSS satellite modeling: long-term orbit behavior

    NASA Astrophysics Data System (ADS)

    Rodriguez-Solano, C. J.; Hugentobler, U.; Steigenberger, P.; Sosnica, K.; Fritsche, M.

    2012-04-01

    Modeling of non-conservative forces is a key issue for precise orbit determination of GNSS satellites. Furthermore, mismodeling of these forces has the potential to explain orbit-related frequencies found in GPS-derived station coordinates and geocenter, as well as the observed bias in the SLR-GPS residuals. Due to the complexity of the non-conservative forces, usually they have been compensated by empirical models based on the real in-orbit behavior of the satellites. Recent studies have focused on the physical/analytical modeling of solar radiation pressure, Earth radiation pressure, thermal effects, antenna thrust, among different effects. However, it has been demonstrated that pure physical models fail to predict the real orbit behavior with sufficient accuracy. In this study we use a recently developed solar radiation pressure model based on the physical interaction between solar radiation and satellite, but also capable of fitting the GNSS tracking data, called adjustable box-wing model. Furthermore, Earth radiation pressure and antenna thrust are included as a priori acceleration. The adjustable parameters of the box-wing model are surface optical properties, the so-called Y-bias and a parameter capable of compensating for non-nominal orientation of the solar panels. Using the adjustable box-wing model a multi-year GPS/GLONASS solution has been computed, using a processing scheme derived from CODE (Center for Orbit Determination in Europe). This multi-year solution allows studying the long-term behavior of satellite orbits, box-wing parameters and geodetic parameters like station coordinates and geocenter. Moreover, the accuracy of GNSS orbits is assessed by using SLR data. This evaluation also allows testing, whether the current SLR-GPS bias could be further reduced.

  20. Non-Conservative Variational Approximation for Nonlinear Schrodinger Equations and its Applications

    NASA Astrophysics Data System (ADS)

    Rossi, Julia M.

    Recently, Galley [Phys. Rev. Lett. 110, 174301 (2013)] proposed an initial value problem formulation of Hamilton's principle applied to non-conservative systems. Here, we explore this formulation for complex partial differential equations of the nonlinear Schrodinger (NLS) type, using the non-conservative variational approximation (NCVA) outlined by Galley. We compare the formalism of the NCVA to two variational techniques used in dissipative systems; namely, the perturbed variational approximation and a generalization of the so-called Kantorovitch method. We showcase the relevance of the NCVA method by exploring test case examples within the NLS setting including combinations of linear and density dependent loss and gain. We also present an example applied to exciton-polariton condensates that intrinsically feature loss and a spatially dependent gain term. We also study a variant of the NLS used in optical systems called the Lugiato-Lefever (LL) model applied to (i) spontaneous temporal symmetry breaking instability in a coherently-driven optical Kerr resonator observed experimentally by Xu and Coen in Opt. Lett. 39, 3492 (2014) and (ii) temporal tweezing of cavity solitons in a passive loop of optical fiber pumped by a continuous-wave laser beam observed experimentally by Jang, Erkintalo, Coen, and Murdoch in Nat. Commun. 6, 7370 (2015). For application (i) we perform a detailed stability analysis and analyze the temporal bifurcation structure of stationary symmetric configurations and the emerging asymmetric states as a function of the pump power. For intermediate pump powers a pitchfork loop is responsible for the destabilization of symmetric states towards stationary asymmetric ones while at large pump powers we find the emergence of periodic asymmetric solutions via a Hopf bifurcation. For application (ii) we study the existence and dynamics of cavity solitons through phase-modulation of the holding beam. We find parametric regions for the manipulation of

  1. Basic amino-acid side chains regulate transmembrane integrin signalling.

    PubMed

    Kim, Chungho; Schmidt, Thomas; Cho, Eun-Gyung; Ye, Feng; Ulmer, Tobias S; Ginsberg, Mark H

    2011-12-18

    Side chains of Lys/Arg near transmembrane domain (TMD) membrane-water interfaces can 'snorkel', placing their positive charge near negatively charged phospholipid head groups; however, snorkelling's functional effects are obscure. Integrin β TMDs have such conserved basic amino acids. Here we use NMR spectroscopy to show that integrin β(3)(Lys 716) helps determine β(3) TMD topography. The α(ΙΙb)β(3) TMD structure indicates that precise β(3) TMD crossing angles enable the assembly of outer and inner membrane 'clasps' that hold the αβ TMD together to limit transmembrane signalling. Mutation of β(3)(Lys 716) caused dissociation of α(ΙΙb)β(3) TMDs and integrin activation. To confirm that altered topography of β(3)(Lys 716) mutants activated α(ΙΙb)β(3), we used directed evolution of β(3)(K716A) to identify substitutions restoring default state. Introduction of Pro(711) at the midpoint of β(3) TMD (A711P) increased α(ΙΙb)β(3) TMD association and inactivated integrin α(ΙΙb)β(3)(A711P,K716A). β(3)(Pro 711) introduced a TMD kink of 30 ± 1° precisely at the border of the outer and inner membrane clasps, thereby decoupling the tilt between these segments. Thus, widely occurring snorkelling residues in TMDs can help maintain TMD topography and membrane-embedding, thereby regulating transmembrane signalling.

  2. Mechanical damage to Escherichia coli cells in a model of amino-acid crystal fermentation.

    PubMed

    Okutani, Satoshi; Iwai, Takayoshi; Iwatani, Shintaro; Kondo, Kazuya; Osumi, Tsuyoshi; Tsujimoto, Nobuharu; Matsuno, Kiyoshi

    2012-04-01

    We investigated the mechanical damage to the Escherichia coli cell caused by polyvinyl chloride particles as a model of amino-acid crystal fermentation. Our results indicated that the glucose-consumption rate and the intracellular ATP concentration temporarily increased by the mechanical damage, and decreased after considerable damage had occurred on cell membrane. PMID:22153714

  3. Precision non-conservative force modelling for Low Earth Orbiting spacecraft

    NASA Astrophysics Data System (ADS)

    Sibthorpe, Anthony John

    Low Earth Orbiting spacecraft are used in various ways for remote observation and measurement of system Earth some classes of measurements are only useful when modelled in a spatial reference frame. As the position of a satellite at a particular epoch is used to provide a fixed point of reference, it is vital that we know these positions both accurately and precisely. Non-conservative forces, which change the energy state of a spacecraft system, can have a dramatic effect on the estimated position of a satellite if unmodelled or, as is often the case, are modelled only crudely. Downstream Earth observation data can inherit significant errors as a result. As an example of this, it has been recognised that apparent long wavelength signals can be introduced into interferometric synthetic aperture radar (SAR) images by orbit error. Such images are used to monitor surface deformation, and may provide an indication of strain accumulation as a pre-cursor to Earthquake activity. It makes sense therefore to better model these non-conservative forces, thus improving the quality of the Earth observation data. This project develops precise methodologies for modelling of solar radiation pressure / thermal re-radiation / eclipse modelling / Earth radiation pressure / spacecraft internal heat distribution / on-board instrument power output, and applies these techniques to the European Space Agency's ENVISAT satellite. This complicated satellite has necessitated the development of a significant number of new algorithms for dealing with a large number of geometric primitives. A graphical display tool, developed during this research, allows rapid model development and improved error checking. Resultant models are incorporated into the GEODYN II orbit determination software, developed at NASA's Goddard Space Flight Centre. Precise orbits computed using tracking data in combination with the newly developed force models are compared against precise orbits generated using nominal force

  4. Non-conservation of global charges in the Brane Universe and baryogenesis

    NASA Astrophysics Data System (ADS)

    Dvali, Gia; Gabadadze, Gregory

    1999-08-01

    We argue that global charges, such as baryon or lepton number, are not conserved in theories with the Standard Model fields localized on the brane which propagates in higher-dimensional space-time. The global-charge non-conservation is due to quantum fluctuations of the brane surface. These fluctuations create ``baby branes'' that can capture some global charges and carry them away into the bulk of higher-dimensional space. Such processes are exponentially suppressed at low-energies, but can be significant at high enough temperatures or energies. These effects can lead to a new, intrinsically high-dimensional mechanism of baryogenesis. Baryon asymmetry might be produced due either to ``evaporation'' into the baby branes, or creation of the baryon number excess in collisions of two Brane Universes. As an example we discuss a possible cosmological scenario within the recently proposed ``Brane Inflation'' framework. Inflation is driven by displaced branes which slowly fall on top of each other. When the branes collide inflation stops and the Brane Universe reheats. During this non-equilibrium collision baryon number can be transported from one brane to another one. This results in the baryon number excess in our Universe which exactly equals to the hidden ``baryon number'' deficit in the other Brane Universe. © 1999

  5. INTERACTING BINARIES WITH ECCENTRIC ORBITS. II. SECULAR ORBITAL EVOLUTION DUE TO NON-CONSERVATIVE MASS TRANSFER

    SciTech Connect

    Sepinsky, J. F.; Willems, B.; Kalogera, V.; Rasio, F. A.

    2009-09-10

    We investigate the secular evolution of the orbital semimajor axis and eccentricity due to mass transfer in eccentric binaries, allowing for both mass and angular momentum loss from the system. Adopting a delta function mass transfer rate at the periastron of the binary orbit, we find that, depending on the initial binary properties at the onset of mass transfer, the orbital semimajor axis and eccentricity can either increase or decrease at a rate linearly proportional to the magnitude of the mass transfer rate at periastron. The range of initial binary mass ratios and eccentricities that lead to increasing orbital semimajor axes and eccentricities broadens with increasing degrees of mass loss from the system and narrows with increasing orbital angular momentum loss from the binary. Comparison with tidal evolution timescales shows that the usual assumption of rapid circularization at the onset of mass transfer in eccentric binaries is not justified, irrespective of the degree of systemic mass and angular momentum loss. This work extends our previous results for conservative mass transfer in eccentric binaries and can be incorporated into binary evolution and population synthesis codes to model non-conservative mass transfer in eccentric binaries.

  6. Self-organized criticality occurs in non-conservative neuronal networks during `up' states

    NASA Astrophysics Data System (ADS)

    Millman, Daniel; Mihalas, Stefan; Kirkwood, Alfredo; Niebur, Ernst

    2010-10-01

    During sleep, under anaesthesia and in vitro, cortical neurons in sensory, motor, association and executive areas fluctuate between so-called up and down states, which are characterized by distinct membrane potentials and spike rates. Another phenomenon observed in preparations similar to those that exhibit up and down states-such as anaesthetized rats, brain slices and cultures devoid of sensory input, as well as awake monkey cortex-is self-organized criticality (SOC). SOC is characterized by activity `avalanches' with a branching parameter near unity and size distribution that obeys a power law with a critical exponent of about -3/2. Recent work has demonstrated SOC in conservative neuronal network models, but critical behaviour breaks down when biologically realistic `leaky' neurons are introduced. Here, we report robust SOC behaviour in networks of non-conservative leaky integrate-and-fire neurons with short-term synaptic depression. We show analytically and numerically that these networks typically have two stable activity levels, corresponding to up and down states, that the networks switch spontaneously between these states and that up states are critical and down states are subcritical.

  7. Rolling vs. Sliding: The inclusion of non-conservative work in the classic comparison

    NASA Astrophysics Data System (ADS)

    Chediak, Alex; Buehler, Terry

    2010-03-01

    A semester-long mechanics course typically covers moment of inertia, angular velocity, and rolling. A classic comparison is made between rolling without slipping and sliding without friction. In either case, no non-conservation work is performed---all the gravitational potential energy that the rolling or sliding object possesses at the top of the incline plane is converted into kinetic energy. In the case of the sliding object, the kinetic energy term is simply .5ex1 -.1em/ -.15em.25ex2 mv^2. In the case of the rolling object, the kinetic energy term is .5ex1 -.1em/ -.15em.25ex2 mv^2 + .5ex1 -.1em/ -.15em.25ex2 Iφ^2. The friction here is static not kinetic, so it does no mechanical work. Since the sliding object has no angular velocity, its linear velocity is greater than that of the rolling object, and it reaches the bottom of the track faster. But if a rolling and sliding object, each of the same material, were to race down an incline plane, which would win? The answer depends on the effective coefficient of friction, C. If C > μs, which will occur at angles approaching 90^o, the rolling object slips. And if C < μk, the rolling object has a greater linear acceleration and wins the race to the bottom. Experimental results to verify a theoretical model (including the dependency on incline angle) will also be presented.

  8. Rad51 Inhibits Translocation Formation by Non-Conservative Homologous Recombination in Saccharomyces cerevisiae

    PubMed Central

    Manthey, Glenn M.; Bailis, Adam M.

    2010-01-01

    Chromosomal translocations are a primary biological response to ionizing radiation (IR) exposure, and are likely to result from the inappropriate repair of the DNA double-strand breaks (DSBs) that are created. An abundance of repetitive sequences in eukaryotic genomes provides ample opportunity for such breaks to be repaired by homologous recombination (HR) between non-allelic repeats. Interestingly, in the budding yeast, Saccharomyces cerevisiae the central strand exchange protein, Rad51 that is required for DSB repair by gene conversion between unlinked repeats that conserves genomic structure also suppresses translocation formation by several HR mechanisms. In particular, Rad51 suppresses translocation formation by single-strand annealing (SSA), perhaps the most efficient mechanism for translocation formation by HR in both yeast and mammalian cells. Further, the enhanced translocation formation that emerges in the absence of Rad51 displays a distinct pattern of genetic control, suggesting that this occurs by a separate mechanism. Since hypomorphic mutations in RAD51 in mammalian cells also reduce DSB repair by conservative gene conversion and stimulate non-conservative repair by SSA, this mechanism may also operate in humans and, perhaps contribute to the genome instability that propels the development of cancer. PMID:20686691

  9. Comparison of the reduced dynamical orbit parametrization and precise non-conservative orbit force modeling for DORIS satellites

    NASA Astrophysics Data System (ADS)

    Stepanek, P.; Rodriguez-Solano, C.; Filler, V.; Hugentobler, U.

    2011-12-01

    The focus of the studies is the analysis of the comparison between two different approaches for LEO satellite orbit estimation employing DORIS measurements. The first one is the reduced-dynamical model, based on the orbit modeling by using the empirical and the pseudo-stochastic parameters. The second approach includes the attitude models and the CNES-developed satellite macromodels, with modeling of non-conservative acceleration, i.e., Sun radiation pressure, Earth radiation pressure and atmospheric drag. Both approaches are used at analysis centers providing DORIS solutions. The reduced-dynamical modeling is currently used by the GOP analysis center, which achieves similar accuracy of the free-network solutions as the other centers utilizing a precise non-conservative force modeling. The GOP works with a modified version of the Bernese GPS Software that has not included the non-conservative modeling. This limitation is now overcome by the new scientific modification of the software, which opens the unique possibility to compare both approaches by using the same software platform. We compare external and internal precision of the estimated orbits. We also analyze the individual satellite free-network DORIS solutions and time-series of derived parameters, i.e., station coordinates, TRF scale, the geocenter variations and the Earth rotation parameters. The studies highlight the main differences in the results that should answer the question whether the modeling of non-conservative forces including the CNES box-wing satellite models actually brings a significant improvement to the DORIS solutions.

  10. Non-conservative behavior of fluorescent dissolved organic matter (FDOM) within a subterranean estuary

    NASA Astrophysics Data System (ADS)

    Suryaputra, I. G. N. A.; Santos, I. R.; Huettel, M.; Burnett, W. C.; Dittmar, T.

    2015-11-01

    The role of submarine groundwater discharge (SGD) in releasing fluorescent dissolved organic matter (FDOM) to the coastal ocean and the possibility of using FDOM as a proxy for dissolved organic carbon (DOC) was investigated in a subterranean estuary in the northeastern Gulf of Mexico (Turkey Point, Florida). FDOM was continuously monitored for three weeks in shallow beach groundwater and in the adjacent coastal ocean. Radon (222Rn) was used as a natural groundwater tracer. FDOM and DOC correlated in groundwater and seawater samples, implying that FDOM may be a proxy of DOC in waters influenced by SGD. A mixing model using salinity as a seawater tracer revealed FDOM production in the high salinity region of the subterranean estuary. This production was probably a result of infiltration and transformation of labile marine organic matter in the beach sediments. The non-conservative FDOM behavior in this subterranean estuary differs from most surface estuaries where FDOM typically behaves conservatively. At the study site, fresh and saline SGD delivered about 1800 mg d-1 of FDOM (quinine equivalents) to the coastal ocean per meter of shoreline. About 11% of this input was related to fresh SGD, while 89% were related to saline SGD resulting from FDOM production within the shallow aquifer. If these fluxes are representative of the Florida Gulf Coast, SGD-derived FDOM fluxes would be equivalent to at least 18% of the potential regional riverine FDOM inputs. To reduce uncertainties related to the scarcity of FDOM data, further investigations of river and groundwater FDOM inputs in Florida and elsewhere are necessary.

  11. Tracing non-conservative mass transfer eras in close binaries from observed period variations

    NASA Astrophysics Data System (ADS)

    Nanouris, N.; Kalimeris, A.; Antonopoulou, E.; Rovithis-Livaniou, H.

    2013-09-01

    The pure information directly taken from the observed orbital evolution of eclipsing binary stars (centuries at most) is valuable for the study of many important physical mechanisms related to the stellar structure. Especially in the case of eclipsing binary systems, this may happen by monitoring their eclipse timing variations, i.e. by means of an O-C diagram analysis. As long as a binary system attains a semi-detached configuration, material begins to flow from the component that fills its Roche lobe toward its mate through the first Lagrangian (L1) point. Here, we examine two non conservative mass transfer (MT) paths. The MT process is then accompanied by mass and angular momentum loss from the system. In the first path, angular momentum is removed through a hot spot which re-emits part of the incoming material, and in the second, angular momentum is carried away via an outer Lagrangian point (L2/L3) due to the small accumulating efficiency of the accretion disk surrounding the gainer. Dealing with the less massive component as the donor in the latter path, it is shown that there is always a critical mass ratio over which the period is expected to decrease, contrary to what the fully conservative MT predicts. Consistent with our expectations, the critical values become progressively smaller as the degree of liberalism is gradually widened. The O-C diagram of several semi-detached systems, expecting to experience a liberal era, is individually examined aiming to estimate both the mass transfer and the mass loss rate.

  12. Non-Conserved Residues in Clostridium acetobutylicum tRNAAla Contribute to tRNA Tuning for Efficient Antitermination of the alaS T Box Riboswitch

    PubMed Central

    Liu, Liang-Chun; Grundy, Frank J.; Henkin, Tina M.

    2015-01-01

    The T box riboswitch regulates expression of amino acid-related genes in Gram-positive bacteria by monitoring the aminoacylation status of a specific tRNA, the binding of which affects the folding of the riboswitch into mutually exclusive terminator or antiterminator structures. Two main pairing interactions between the tRNA and the leader RNA have been demonstrated to be necessary, but not sufficient, for efficient antitermination. In this study, we used the Clostridium acetobutylicum alaS gene, which encodes alanyl-tRNA synthetase, to investigate the specificity of the tRNA response. We show that the homologous C. acetobutylicum tRNAAla directs antitermination of the C. acetobutylicum alaS gene in vitro, but the heterologous Bacillus subtilis tRNAAla (with the same anticodon and acceptor end) does not. Base substitutions at positions that vary between these two tRNAs revealed synergistic and antagonistic effects. Variation occurs primarily at positions that are not conserved in tRNAAla species, which indicates that these non-conserved residues contribute to optimal antitermination of the homologous alaS gene. This study suggests that elements in tRNAAla may have coevolved with the homologous alaS T box leader RNA for efficient antitermination. PMID:26426057

  13. Fermentation of Agave tequilana juice by Kloeckera africana: influence of amino-acid supplementations.

    PubMed

    Valle-Rodríguez, Juan Octavio; Hernández-Cortés, Guillermo; Córdova, Jesús; Estarrón-Espinosa, Mirna; Díaz-Montaño, Dulce María

    2012-02-01

    This study aimed to improve the fermentation efficiency of Kloeckera africana K1, in tequila fermentations. We investigated organic and inorganic nitrogen source requirements in continuous K. africana fermentations fed with Agave tequilana juice. The addition of a mixture of 20 amino-acids greatly improved the fermentation efficiency of this yeast, increasing the consumption of reducing sugars and production of ethanol, compared with fermentations supplemented with ammonium sulfate. The preference of K. africana for each of the 20 amino-acids was further determined in batch fermentations and we found that asparagine supplementation increased K. africana biomass production, reducing sugar consumption and ethanol production (by 30, 36.7 and 45%, respectively) over fermentations supplemented with ammonium sulfate. Therefore, asparagine appears to overcome K. africana nutritional limitation in Agave juice. Surprisingly, K. africana produced a high concentration of ethanol. This contrasts to poor ethanol productivities reported for other non-Saccharomyces yeasts indicating a relatively high ethanol tolerance for the K. africana K1 strain. Kloeckera spp. strains are known to synthesize a wide variety of volatile compounds and we have shown that amino-acid supplements influenced the synthesis by K. africana of important metabolites involved in the bouquet of tequila. The findings of this study have revealed important nutritional limitations of non-Saccharomyces yeasts fermenting Agave tequilana juice, and have highlighted the potential of K. africana in tequila production processes.

  14. Fermentation of Agave tequilana juice by Kloeckera africana: influence of amino-acid supplementations.

    PubMed

    Valle-Rodríguez, Juan Octavio; Hernández-Cortés, Guillermo; Córdova, Jesús; Estarrón-Espinosa, Mirna; Díaz-Montaño, Dulce María

    2012-02-01

    This study aimed to improve the fermentation efficiency of Kloeckera africana K1, in tequila fermentations. We investigated organic and inorganic nitrogen source requirements in continuous K. africana fermentations fed with Agave tequilana juice. The addition of a mixture of 20 amino-acids greatly improved the fermentation efficiency of this yeast, increasing the consumption of reducing sugars and production of ethanol, compared with fermentations supplemented with ammonium sulfate. The preference of K. africana for each of the 20 amino-acids was further determined in batch fermentations and we found that asparagine supplementation increased K. africana biomass production, reducing sugar consumption and ethanol production (by 30, 36.7 and 45%, respectively) over fermentations supplemented with ammonium sulfate. Therefore, asparagine appears to overcome K. africana nutritional limitation in Agave juice. Surprisingly, K. africana produced a high concentration of ethanol. This contrasts to poor ethanol productivities reported for other non-Saccharomyces yeasts indicating a relatively high ethanol tolerance for the K. africana K1 strain. Kloeckera spp. strains are known to synthesize a wide variety of volatile compounds and we have shown that amino-acid supplements influenced the synthesis by K. africana of important metabolites involved in the bouquet of tequila. The findings of this study have revealed important nutritional limitations of non-Saccharomyces yeasts fermenting Agave tequilana juice, and have highlighted the potential of K. africana in tequila production processes. PMID:21761236

  15. Amino-acid substitutions at codon 13 of the N-ras oncogene in human acute myeloid leukaemia

    NASA Astrophysics Data System (ADS)

    Bos, Johannes L.; Toksoz, Deniz; Marshall, Christopher J.; Verlaan-de Vries, Matty; Veeneman, Gerrit H.; van der Eb, Alex J.; van Boom, Jacques H.; Janssen, Johannes W. G.; Steenvoorden, Ada C. M.

    1985-06-01

    DNAs from four out of five patients with acute myeloid leukaemia (AML) tested by an in vivo selection assay in nude mice using transfected mouse NIH 3T3 cells were found to contain an activated N-ras oncogene. Using a set of synthetic oligonucleotide probes, we have detected a mutation at codon 13 in all four genes. The same codon is mutated in an additional AML DNA that is positive in the focus-formation assay on 3T3 cells. DNA from the peripheral blood of one patient in remission does not contain a codon 13 mutation.

  16. Multi-scale coarse-graining of non-conservative interactions in molecular liquids

    SciTech Connect

    Izvekov, Sergei Rice, Betsy M.

    2014-03-14

    A new bottom-up procedure for constructing non-conservative (dissipative and stochastic) interactions for dissipative particle dynamics (DPD) models is described and applied to perform hierarchical coarse-graining of a polar molecular liquid (nitromethane). The distant-dependent radial and shear frictions in functional-free form are derived consistently with a chosen form for conservative interactions by matching two-body force-velocity and three-body velocity-velocity correlations along the microscopic trajectories of the centroids of Voronoi cells (clusters), which represent the dissipative particles within the DPD description. The Voronoi tessellation is achieved by application of the K-means clustering algorithm at regular time intervals. Consistently with a notion of many-body DPD, the conservative interactions are determined through the multi-scale coarse-graining (MS-CG) method, which naturally implements a pairwise decomposition of the microscopic free energy. A hierarchy of MS-CG/DPD models starting with one molecule per Voronoi cell and up to 64 molecules per cell is derived. The radial contribution to the friction appears to be dominant for all models. As the Voronoi cell sizes increase, the dissipative forces rapidly become confined to the first coordination shell. For Voronoi cells of two and more molecules the time dependence of the velocity autocorrelation function becomes monotonic and well reproduced by the respective MS-CG/DPD models. A comparative analysis of force and velocity correlations in the atomistic and CG ensembles indicates Markovian behavior with as low as two molecules per dissipative particle. The models with one and two molecules per Voronoi cell yield transport properties (diffusion and shear viscosity) that are in good agreement with the atomistic data. The coarser models produce slower dynamics that can be appreciably attributed to unaccounted dissipation introduced by regular Voronoi re-partitioning as well as by larger

  17. Atomic parity non-conservation: the francium anapole project of the FrPNC collaboration at TRIUMF

    NASA Astrophysics Data System (ADS)

    Aubin, S.; Behr, J. A.; Collister, R.; Flambaum, V. V.; Gomez, E.; Gwinner, G.; Jackson, K. P.; Melconian, D.; Orozco, L. A.; Pearson, M. R.; Sheng, D.; Sprouse, G. D.; Tandecki, M.; Zhang, J.; Zhao, Y.

    2013-03-01

    We present a method for measuring the nuclear anapole in a string of francium isotopes. The anapole is a parity non-conserving electromagnetic moment that enables parity-forbidden transitions between ground state hyperfine levels of an atom. The experiment is run by the FrPNC collaboration and relies on a beam of artificially-produced francium from the ISAC facility at TRIUMF.

  18. Flow path functioning identified from fundamental dynamics in sub-hourly, non-conservative stream chemistry

    NASA Astrophysics Data System (ADS)

    Chappell, N. A.; Jones, T.

    2013-12-01

    Within upland streams, concentration & load of many solutes (e.g. H+, DOC) varies very rapidly through storm periods. The shape & features of concentration or load chemographs are an expression of the fundamental dynamics in hydrologic & biogeochemical delivery mechanisms integrated at basin scales. If storm-period chemographs are grossly under-sampled so that time-series does not represent the true chemograph shape, then numerical descriptors of this shape or of the dynamic relationship between controlling variables (e.g. rainfall) & the chemograph will be distorted from true values (Littlewood 1992 IH Rpt 117; Littlewood & Croke 2013 Hydrol Res). Distortions of these dynamic response characteristics or DRCs (model parameters) can then lead to misinterpretation of hydrologic & biogeochemical processes via errors in relative contributions of identified flow paths, rates of propagation along these paths etc. A transfer function (TF) approach can be used to illustrate minimum sampling intensities needed to avoid these errors. Given 15-min observations, CAPTAIN-RIV identification routines for continuous-time TFs give Time Constants (TCs) of only 2 hrs for fast components of responses of rainfall to H+ load in Llyn Brianne streams (Chappell et al 2013 BHS). Given that Time Series Analysis dictates a sampling intensity five times finer than the TC, sampling at 24 min intervals or shorter was needed & achieved in this example. Considerable work is now focused on modeling of chemically-conservative river constituents (namely chloride & water isotopes) to help determine differences in residence times, storage & other DRCs of rainfall-streamflow & associated solute paths (Hrachowitz et al 2013 Hydrol Earth Syst Sci). Comparatively little modeling has focused on high frequency (i.e. sub-hourly), non-conservative river solutes (e.g. H+, DOC). Modeling of these basin-integrated variables should be considered complementary to that for conservative solutes, given: (1) their

  19. Amino-acid sequence of a cooperative, dimeric myoglobin from the gastropod mollusc, Buccinum undatum L.

    PubMed

    Wen, D; Laursen, R A

    1994-10-19

    The complete amino-acid sequence of a dimeric myoglobin from the radular mussel of the gastropod mollusc, Buccinum undatum L. has been determined. The globin, which shows cooperative binding of oxygen, contains 146 amino acids, is N-terminal aminoacetylated, and has histidine residues at position 65 and 97, corresponding to the heme-binding histidines seen in mammalian myoglobins. It shows about 75% and 50% homology, respectively, with the dimeric molluscan myoglobins from Busycon canaliculatum and Cerithidea rhizophorarum, the former of which also shows weak cooperatively, but much less similarity to other species of myoglobin and hemoglobin.

  20. The Modeling of Time-Varying Stream Water Age Distributions: Preliminary Investigations with Non-Conservative Solutes

    NASA Astrophysics Data System (ADS)

    Wilusz, D. C.; Harman, C. J.; Ball, W. P.

    2014-12-01

    Modeling the dynamics of chemical transport from the landscape to streams is necessary for water quality management. Previous work has shown that estimates of the distribution of water age in streams, the transit time distribution (TTD), can improve prediction of the concentration of conservative tracers (i.e., ones that "follow the water") based on upstream watershed inputs. A major challenge however has been accounting for climate and transport variability when estimating TDDs at the catchment scale. In this regard, Harman (2014, in review) proposed the Omega modeling framework capable of using watershed hydraulic fluxes to approximate the time-varying TTD. The approach was previously applied to the Plynlimon research watershed in Wales to simulate stream concentration dynamics of a conservative tracer (chloride) including 1/f attenuation of the power spectra density. In this study we explore the extent to which TTDs estimated by the Omega model vary with the concentration of non-conservative tracers (i.e., ones whose concentrations are also affected by transformations and interactions with other phases). First we test the hypothesis that the TTD calibrated in Plynlimon can explain a large part of the variation in non-conservative stream water constituents associated with storm flow (acidity, Al, DOC, Fe) and base flow (Ca, Si). While controlling for discharge, we show a correlation between the percentage of water of different ages and constituent concentration. Second, we test the hypothesis that TTDs help explain variation in stream nitrate concentration, which is of particular interest for pollution control but can be highly non-conservative. We compare simulation runs from Plynlimon and the agricultural Choptank watershed in Maryland, USA. Following a top-down approach, we estimate nitrate concentration as if it were a conservative tracer and examine the structure of residuals at different temporal resolutions. Finally, we consider model modifications to

  1. Sensitivity test of a blue-detuned dipole trap designed for parity non-conservation measurements in Fr

    NASA Astrophysics Data System (ADS)

    Sheng, D.; Zhang, J.; Orozco, L. A.

    2012-04-01

    A dynamic blue-detuned optical dipole trap with stable 87Rb atoms produces a differential ac Stark shift of 18 Hz in the ground state hyperfine transition, and it preserves the ground state hyperfine superpositions for a long coherence time of 180 ms. The trapped atoms undergoing microwave Rabi oscillations are sensitive to a small signal, artificially generated with a second microwave source, phase locked to the first allowing a simple and effective method for determining signal-to-noise ratio limits through interference techniques. This provides an excellent means of calibrating sensitivity in experiments such as our ongoing Fr parity non-conservation measurement.

  2. Accurate Measurement of the Effects of All Amino-Acid Mutations on Influenza Hemagglutinin

    PubMed Central

    Doud, Michael B.; Bloom, Jesse D.

    2016-01-01

    Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We and others have combined high-throughput mutagenesis with deep sequencing to estimate the effects of large numbers of mutations to influenza genes. However, these measurements have suffered from substantial experimental noise due to a variety of technical problems, the most prominent of which is bottlenecking during the generation of mutant viruses from plasmids. Here we describe advances that ameliorate these problems, enabling us to measure with greatly improved accuracy and reproducibility the effects of all amino-acid mutations to an H1 influenza hemagglutinin on viral replication in cell culture. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm at much higher resolution the results of previous studies suggesting that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. We also show that other regions of hemagglutinin—including the stalk epitopes targeted by broadly neutralizing antibodies—have a much lower inherent capacity to tolerate point mutations. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution. PMID:27271655

  3. Polarization of M2 macrophages requires Lamtor1 that integrates cytokine and amino-acid signals

    PubMed Central

    Kimura, Tetsuya; Nada, Shigeyuki; Takegahara, Noriko; Okuno, Tatsusada; Nojima, Satoshi; Kang, Sujin; Ito, Daisuke; Morimoto, Keiko; Hosokawa, Takashi; Hayama, Yoshitomo; Mitsui, Yuichi; Sakurai, Natsuki; Sarashina-Kida, Hana; Nishide, Masayuki; Maeda, Yohei; Takamatsu, Hyota; Okuzaki, Daisuke; Yamada, Masaki; Okada, Masato; Kumanogoh, Atsushi

    2016-01-01

    Macrophages play crucial roles in host defence and tissue homoeostasis, processes in which both environmental stimuli and intracellularly generated metabolites influence activation of macrophages. Activated macrophages are classified into M1 and M2 macrophages. It remains unclear how intracellular nutrition sufficiency, especially for amino acid, influences on macrophage activation. Here we show that a lysosomal adaptor protein Lamtor1, which forms an amino-acid sensing complex with lysosomal vacuolar-type H+-ATPase (v-ATPase), and is the scaffold for amino acid-activated mTORC1 (mechanistic target of rapamycin complex 1), is critically required for M2 polarization. Lamtor1 deficiency, amino-acid starvation, or inhibition of v-ATPase and mTOR result in defective M2 polarization and enhanced M1 polarization. Furthermore, we identified liver X receptor (LXR) as the downstream target of Lamtor1 and mTORC1. Production of 25-hydroxycholesterol is dependent on Lamtor1 and mTORC1. Our findings demonstrate that Lamtor1 plays an essential role in M2 polarization, coupling immunity and metabolism. PMID:27731330

  4. Exploring the evolution of standard amino-acid alphabet: When genomics meets thermodynamics

    SciTech Connect

    Zhang, Hong-Yu . E-mail: zhanghy@sdut.edu.cn

    2007-08-03

    One of the most intriguing aspects of life is that despite the diversified apparent shapes, similar building blocks and infrastructures, such as standard amino acids and canonical genetic codes, are shared by most life on Earth. Thus, it is challenging to explore: why nature just selects these building blocks and strategies from numerous candidates to construct life? Was this deterministic or fortuitous? Thanks to the rapid progress in genomics, bioinformatics and synthetic biology, more and more basic principles underlying life design and construction were disclosed in the past decade. However, since the origin of early life is substantially a chemical process, to understand the enigma of life origin, chemists' efforts can not be neglected. In this paper, we focus on the evolution of standard amino-acid alphabet and indicate that chemistry, especially thermodynamics, is indeed critical to understanding the forming mechanisms of amino-acid alphabet. It is revealed that nature prefers low free energy and thus ubiquitous (cheap) small amino acids when beginning to build life, which is compatible with many recent findings from genomics and bioinformatics.

  5. Accurate Measurement of the Effects of All Amino-Acid Mutations on Influenza Hemagglutinin.

    PubMed

    Doud, Michael B; Bloom, Jesse D

    2016-01-01

    Influenza genes evolve mostly via point mutations, and so knowing the effect of every amino-acid mutation provides information about evolutionary paths available to the virus. We and others have combined high-throughput mutagenesis with deep sequencing to estimate the effects of large numbers of mutations to influenza genes. However, these measurements have suffered from substantial experimental noise due to a variety of technical problems, the most prominent of which is bottlenecking during the generation of mutant viruses from plasmids. Here we describe advances that ameliorate these problems, enabling us to measure with greatly improved accuracy and reproducibility the effects of all amino-acid mutations to an H1 influenza hemagglutinin on viral replication in cell culture. The largest improvements come from using a helper virus to reduce bottlenecks when generating viruses from plasmids. Our measurements confirm at much higher resolution the results of previous studies suggesting that antigenic sites on the globular head of hemagglutinin are highly tolerant of mutations. We also show that other regions of hemagglutinin-including the stalk epitopes targeted by broadly neutralizing antibodies-have a much lower inherent capacity to tolerate point mutations. The ability to accurately measure the effects of all influenza mutations should enhance efforts to understand and predict viral evolution. PMID:27271655

  6. Non-conservative behaviors of chromophoric dissolved organic matter in a turbid estuary: Roles of multiple biogeochemical processes

    NASA Astrophysics Data System (ADS)

    Yang, Liyang; Guo, Weidong; Hong, Huasheng; Wang, Guizhi

    2013-11-01

    Chromophoric dissolved organic matter (CDOM) may show notable non-conservative behaviors in many estuaries due to a variety of biogeochemical processes. The partition between CDOM and chromophoric particulate organic matter (CPOM) was examined in the Jiulong Estuary (China) using absorption and fluorescence spectroscopy, which was also compared with microbial and photochemical degradations. The absorption coefficient of water-soluble CPOM (aCPOM(280)) at ambient Milli-Q water pH (6.1) ranged from 0.11 to 7.94 m-1 in the estuary and was equivalent to 5-101% of CDOM absorption coefficient. The aCPOM(280) correlated significantly with the concentration of suspended particulate matter and was highest in the bottom water of turbidity maximum zone. Absorption spectral slope (S275-295) and slope ratio (SR) correlated positively with salinity for both CPOM and CDOM, suggesting decreases in the average molecular weight with increasing salinity. The adsorption of CDOM to re-suspended sediments (at 500 mg L-1) within 2 h was equivalent to 4-26% of the initial aCDOM(280). The adsorption of CDOM to particles was less selective with respect to various CDOM constituents, while the microbial degradation resulted decreases in S275-295 and SR of CDOM and preferential removal of protein-like components. The partition between CPOM and CDOM represented a rapid and important process for the non-conservative behavior of CDOM in turbid estuaries.

  7. Human miR-1271 is a miR-96 paralog with distinct non-conserved brain expression pattern

    PubMed Central

    Jensen, Kevin P.; Covault, Jonathan

    2011-01-01

    Recent deep-sequencing efforts have identified many novel non-conserved small RNAs that are expressed at low levels in certain mammalian cells. Whether these small RNAs are important for mammalian physiology is debatable, therefore we explored the function of one such RNA, human miR-1271. This small RNA is similar in sequence to miR-96, a highly conserved microRNA that when mutated causes hearing loss in humans and mice. Although the miR-1271 and miR-96 sequences differ slightly, our in vitro assays indicate that they have an identical regulatory activity. We have identified brain-expressed mRNAs from genes including, GPHN, RGS2, HOMER1 and KCC2, which share the same miR-96 and miR-1271 regulatory elements. Interestingly, human miR-1271 is expressed abundantly in brain tissue, where miR-96 is not highly expressed. The rodent miR-1271 precursor contains several sequence differences in the precursor stem, which appear to reduce the efficiency of microRNA processing. Our data indicate that although miR-1271 and miR-96 function identically in vitro, they function to some extent uniquely in vivo. Given the expression patterns and nature of the target genes, miR-1271 may have a significant, although non-conserved, role in regulating aspects of neural development or function in humans. PMID:20864449

  8. Solvent substitution

    SciTech Connect

    Not Available

    1990-01-01

    The DOE Environmental Restoration and Waste Management Office of Technology Development and the Air Force Engineering and Services Center convened the First Annual International Workshop on Solvent Substitution on December 4--7, 1990. The primary objectives of this joint effort were to share information and ideas among attendees in order to enhance the development and implementation of required new technologies for the elimination of pollutants associated with industrial use of hazardous and toxic solvents; and to aid in accelerating collaborative efforts and technology transfer between government and industry for solvent substitution. There were workshop sessions focusing on Alternative Technologies, Alternative Solvents, Recovery/Recycling, Low VOC Materials and Treatment for Environmentally Safe Disposal. The 35 invited papers presented covered a wide range of solvent substitution activities including: hardware and weapons production and maintenance, paint stripping, coating applications, printed circuit boards, metal cleaning, metal finishing, manufacturing, compliance monitoring and process control monitoring. This publication includes the majority of these presentations. In addition, in order to further facilitate information exchange and technology transfer, the US Air Force and DOE solicited additional papers under a general Call for Papers.'' These papers, which underwent review and final selection by a peer review committee, are also included in this combined Proceedings/Compendium. For those involved in handling, using or managing hazardous and toxic solvents, this document should prove to be a valuable resource, providing the most up-to-date information on current technologies and practices in solvent substitution. Individual papers are abstracted separated.

  9. Hydrolysed proteins in preterm formula: influence on plasma aminoacids, blood fatty acids and insulinaemia.

    PubMed

    Agosti, M; Pugni, L; Ramenghi, L A; Mosca, F; Marini, A

    2003-09-01

    The data from the present investigation differ from those of the previous study. The new version of hydrolysed protein formula did not induce changes in insulinaemia or in the insulinaemia/glycaemia ratio in pre- and postprandial samples when compared with the intact protein formula. The investigation also confirmed that branch chain aminoacids regulate insulin secretion and that the length of chain is insulinotropic for fatty acids, while the degree of unsaturation is not able to reduce insulin secretion in the newborn baby. This could be caused by stimulation of insulin output activated by the C20:5 n 3; the effects of fatty acids are probably related more to the variable composition of cell membrane than to the fatty acids circulating levels.

  10. Proliferative response of putative preneoplastic hepatocytes to triiodothyronine, aminoacids, glucagon and heparine.

    PubMed

    Estadella, M D; Pujol, M J; Domingo, J

    1988-03-01

    Proliferative advantage of putative preneoplastic hepatocytes measured as the ratio of tritiated thymidine incorporation into cells of hyperplastic nodules with respect to the incorporation in hepatocytes of extranodular liver has been found to be about 2 in rats treated according to 4 carcinogenesis protocols consisting in one or two cycles of diethylnitrosamine and phenobarbital administration. The proliferative response of hepatocytes in hyperplastic nodules to the intravenous infusion of triiodothyronine, amino-acids, glucagon, and heparine (TAGH) has been found higher or similar--except in one case--than the response of surrounding liver but the proliferative advantage of preneoplastic hepatocytes is lower after TAGH stimulation than in basal conditions in all cases. PMID:3383246

  11. Cytotoxicity and cellular uptake of ZnS:Mn nanocrystals biofunctionalized with chitosan and aminoacids

    NASA Astrophysics Data System (ADS)

    Sajimol Augustine, M.; Anas, Abdulaziz; Das, Ani V.; Sreekanth, S.; Jayalekshmi, S.

    2015-02-01

    Highly luminescent, manganese doped, zinc sulphide (ZnS:Mn) nanocrystals biofunctionalized with chitosan and various aminoacids such as L-citrulline, L-lysine, L-arginine, L-serine, L-histidine and glycine were synthesized by chemical capping co-precipitation method at room temperature, which is a simple and cost effective technique. The synthesized nanocrystals were structurally characterized by TEM, XRD, EDXS and FT-IR spectroscopy techniques. They possess high colloidal stability with strong orange red photoluminescence emission at 598 nm. The intensity of orange red emission has been observed to be maximum in L-citrulline capped ZnS:Mn nanocrystals in which the emission at 420 nm is effectively quenched by surface passivation due to capping. Taking into consideration the prospects of these highly luminescent, bio-compatible ZnS:Mn nanocrystals in bio-imaging applications, cytotoxicity studies were conducted to identify the capping combination which would accomplish minimum toxic effects. ZnS:Mn nanocrystals biofunctionalized with chitosan, L-citrulline, glycine, L-artginine, L-serine and L-histidine showed least toxicity up to 10 nM concentrations in mouse fibroblast L929 cells, which further confirms their cytocompatibility. Also the ZnS:Mn nanocrystals biofunctionalized with L-arginine showed maximum uptake in in vitro studies carried out in human embryonic kidney cells, HEK-293T, which shows the significant role of this particular amino acid in fetoplacental nutrition. The present study highlights the suitability of aminoacid conjugated ZnS:Mn nanocrystals, as promising candidates for biomedical applications.

  12. Vesicles from pH-regulated reversible gemini amino-acid surfactants as nanocapsules for delivery.

    PubMed

    Lv, Jing; Qiao, Weihong; Li, Zongshi

    2016-10-01

    Reversible transition from micelles to vesicles by regulating pH were realized by gemini amino-acid surfactants N,N'-dialkyl-N,N'-diacetate ethylenediamine. Measurement results of ζ-potential at different pH and DLS at varying solvents revealed that the protonation between H(+) and double NCH2COO(-) groups (generating NH(+)CH2COO(-)), expressed as pKa1 and pKa2, is the key driving force to control the aggregation behaviors of gemini surfactant molecule. Effect of pH on the bilayer structure was studied in detail by using steady-state fluorescence spectroscopy of hydrophobic pyrene and Coumarin 153 (C153) respectively and fluorescence resonance energy transfer (FRET) from C153 to Rhodamine 6G (R6G). Various pH-regulated and pH-reversible self-assemblies were obtained in one surfactant system. Vitamin D3 was encapsulated in vesicle bilayers to form nano-VD3-capsules as VD3 supplement agent for health care products. By using the electrostatic attraction between Ca(2+) and double -COO(-) groups, nano-VD3-capsules with Ca(2+) coated outermost layers were prepared as a formulation for VD3 and calcium co-supplement agent. DLS and TEM were performed to check stability and morphology of the nano-capsules. It is concluded that the pH-regulated gemini amino-acid surfactants can be used to construct colloidal systems for delivering hydrophobic drugs or nutritions without lipids at human physiological pH level. PMID:27419647

  13. Vesicles from pH-regulated reversible gemini amino-acid surfactants as nanocapsules for delivery.

    PubMed

    Lv, Jing; Qiao, Weihong; Li, Zongshi

    2016-10-01

    Reversible transition from micelles to vesicles by regulating pH were realized by gemini amino-acid surfactants N,N'-dialkyl-N,N'-diacetate ethylenediamine. Measurement results of ζ-potential at different pH and DLS at varying solvents revealed that the protonation between H(+) and double NCH2COO(-) groups (generating NH(+)CH2COO(-)), expressed as pKa1 and pKa2, is the key driving force to control the aggregation behaviors of gemini surfactant molecule. Effect of pH on the bilayer structure was studied in detail by using steady-state fluorescence spectroscopy of hydrophobic pyrene and Coumarin 153 (C153) respectively and fluorescence resonance energy transfer (FRET) from C153 to Rhodamine 6G (R6G). Various pH-regulated and pH-reversible self-assemblies were obtained in one surfactant system. Vitamin D3 was encapsulated in vesicle bilayers to form nano-VD3-capsules as VD3 supplement agent for health care products. By using the electrostatic attraction between Ca(2+) and double -COO(-) groups, nano-VD3-capsules with Ca(2+) coated outermost layers were prepared as a formulation for VD3 and calcium co-supplement agent. DLS and TEM were performed to check stability and morphology of the nano-capsules. It is concluded that the pH-regulated gemini amino-acid surfactants can be used to construct colloidal systems for delivering hydrophobic drugs or nutritions without lipids at human physiological pH level.

  14. ERK1 nucleocytoplasmic shuttling rate depends on specific N-terminal aminoacids

    SciTech Connect

    Marchi, Matilde; Pancrazi, Laura; Maffei, Margherita; Ratto, G. Michele; Costa, Mario

    2010-07-23

    Despite ERK1 and ERK2 were considered interchangeable isoforms for a long time, their roles are now emerging as only partially overlapping. We recently reported that the nucleocytoplasmic trafficking of GFP-tagged ERK1 is slower than that of ERK2, this difference being caused by a unique domain of ERK1 located at its N-terminus (ERK1-Nt). In the present report we further investigated this issue by asking which were the specific aminoacids involved in such process. By photobleaching strategy, we demonstrated that ERK1-Nt is a domain capable to slow down the nucleocytoplasmic shuttling rate even of a small cargo protein. ERK1-Nt was then dissected into three regions as follows: 1 (aa 1-9), 2 (aa 10-29) and 3, (aa 30-39) that were deleted or mutated at specific sites. Dynamic imaging assessment of the role played by each region in determining the shuttling rate revealed that: region 1 has no significant role, region 2 and specific aminoacids of region 3 (V{sub 31}, K{sub 33,} P{sub 36}) are critical, but singularly do not totally account for the difference in the shuttling rate between ERK1 and 2. Finally, we demonstrated that the nucleocytoplasmic shuttling rate of a passively diffusing protein (mRED) is inversely related to ERK1-Nt-GFP concentrations inside the cell, thus suggesting that ERK1-Nt-GFP occupies the nuclear pore perhaps because of an important affinity of ERK1-Nt for nucleoporins. In conclusion, ERK1-Nt is a domain able per se to confer a slower shuttling rate to a cargo protein. Specific regions within this domain were identified as responsible for this biophysical property.

  15. Sensory Substitution

    NASA Astrophysics Data System (ADS)

    Verrillo, Ronald T.

    The idea that the cutaneous surface may be employed as a substitute for the eyes and ears is by no means a modern notion. Although the sense of touch has long been considered as a surrogate for both the visual and auditory modalities, the focus of this chapter will be on the efforts to develop a tactile substitute for hearing, especially that of human speech. The visual system is our primary means of processing information about environmental space such as orientation, distance, direction and size. It is much less effective in making temporal discriminations. The auditory system is unparalleled in processing information that involves rapid sequences of temporal events, such as speech and music. The tactile sense is capable of processing both spatial and temporal information although not as effective in either domain as the eye or the ear.

  16. Hemoglobin substitutes.

    PubMed

    Anbari, Kevin K; Garino, Jonathan P; Mackenzie, Colin F

    2004-10-01

    Orthopaedic patients frequently require blood transfusions to treat peri-operative anemia. Research in the area of hemoglobin substitutes has been of great interest since it holds the promise of reducing the reliance on allogeneic blood transfusions. The three categories of hemoglobin substitutes are (1) cell-free, extracellular hemoglobin preparations made from human or bovine hemoglobin (hemoglobin-based oxygen carriers or HBOCs); (2) fluorine-substituted linear or cyclic carbon chains with a high oxygen-carrying capacity (perfluorocarbons); and (3) liposome-encapsulated hemoglobin. Of the three, HBOCs have been the most extensively studied and tested in preclinical and clinical trials that have shown success in diminishing the number of blood transfusions as well as an overall favorable side-effect profile. This has been demonstrated in vascular, cardiothoracic, and orthopaedic patients. HBOC-201, which is a preparation of cell-free bovine hemoglobin, has been approved for clinical use in South Africa. These products may well become an important tool for physicians treating peri-operative anemia in orthopaedic patients.

  17. An improved GRACE monthly gravity field solution by modeling the non-conservative acceleration and attitude observation errors

    NASA Astrophysics Data System (ADS)

    Chen, Qiujie; Shen, Yunzhong; Chen, Wu; Zhang, Xingfu; Hsu, Houze

    2016-06-01

    The main contribution of this study is to improve the GRACE gravity field solution by taking errors of non-conservative acceleration and attitude observations into account. Unlike previous studies, the errors of the attitude and non-conservative acceleration data, and gravity field parameters, as well as accelerometer biases are estimated by means of weighted least squares adjustment. Then we compute a new time series of monthly gravity field models complete to degree and order 60 covering the period Jan. 2003 to Dec. 2012 from the twin GRACE satellites' data. The derived GRACE solution (called Tongji-GRACE02) is compared in terms of geoid degree variances and temporal mass changes with the other GRACE solutions, namely CSR RL05, GFZ RL05a, and JPL RL05. The results show that (1) the global mass signals of Tongji-GRACE02 are generally consistent with those of CSR RL05, GFZ RL05a, and JPL RL05; (2) compared to CSR RL05, the noise of Tongji-GRACE02 is reduced by about 21 % over ocean when only using 300 km Gaussian smoothing, and 60 % or more over deserts (Australia, Kalahari, Karakum and Thar) without using Gaussian smoothing and decorrelation filtering; and (3) for all examples, the noise reductions are more significant than signal reductions, no matter whether smoothing and filtering are applied or not. The comparison with GLDAS data supports that the signals of Tongji-GRACE02 over St. Lawrence River basin are close to those from CSR RL05, GFZ RL05a and JPL RL05, while the GLDAS result shows the best agreement with the Tongji-GRACE02 result.

  18. Photochemical abiotic synthesis of amino-acid precursors from simulated planetary atmospheres by vacuum ultraviolet light

    NASA Astrophysics Data System (ADS)

    Takahashi, Jun-Ichi; Masuda, Hitomi; Kaneko, Takeo; Kobayashi, Kensei; Saito, Takeshi; Hosokawa, Teruo

    2005-07-01

    For the purpose of investigating the photon energy dependence of the photoinduced abiotic synthesis of organic molecules, gas mixtures that simulate typical planetary atmospheres, including a carbon source (CO or CH4), a nitrogen source (N2 or NH3), and H2O, were irradiated with synchrotron radiation through a vacuum-ultraviolet transmitting window. Three kinds of window material, fused silica, synthetic quartz, and MgF2, were used as a high-energy-cutting filter, whose absorption-edge energies are 6.4, 8.1, and 10.5 eV, respectively. Three types of gas mixture, Titan-type (CH4-N2-H2O), comet-type (CO-NH3-H2O), and primitive-Earth-type (CO-N2-H2O), were irradiated with vacuum-ultraviolet photons in the three energy ranges. After the irradiation, amino-acid formation yields in the acid-hydrolyzed solution of the product were measured with a high-performance liquid chromatograph method. From the Titan- and comet-type mixtures, amino acids were detected by irradiation with photons lower than 8.1 eV. For both mixtures, the averaged quantum yields of glycine generation in the photon energy region of 7-10.5 eV were of the order of 10-5, which was larger by about one order than that in the region 5-8 eV. On the other hand, from the primitive-Earth-type mixture, amino-acid formation was difficult to detect even with irradiation as high as 10.5 eV, even though amino acids were generated in comparable yields from the Titan- and comet-type mixtures by irradiation with soft x rays or proton beam, whose energies are much higher. These results suggest that the vacuum ultraviolet light is a more effective energy source for the generation of the precursors of bioorganic compounds in extraterrestrial environments than in primitive-Earth atmosphere.

  19. Solubility of xenon in amino-acid solutions. II. Nine less-soluble amino acids

    NASA Astrophysics Data System (ADS)

    Kennan, Richard P.; Himm, Jeffrey F.; Pollack, Gerald L.

    1988-05-01

    Ostwald solubility (L) of xenon gas, as the radioisotope 133Xe, has been measured as a function of solute concentration, at 25.0 °C, in aqueous solutions of nine amino acids. The amino-acid concentrations investigated covered much of their solubility ranges in water, viz., asparagine monohydrate (0-0.19 M), cysteine (0-1.16 M), glutamine (0-0.22 M), histidine (0-0.26 M), isoleucine (0-0.19 M), methionine (0-0.22 M), serine (0-0.38 M), threonine (0-1.4 M), and valine (0-0.34 M). We have previously reported solubility results for aqueous solutions of six other, generally more soluble, amino acids (alanine, arginine, glycine, hydroxyproline, lysine, and proline), of sucrose and sodium chloride. In general, L decreases approximately linearly with increasing solute concentration in these solutions. If we postulate that the observed decreases in gas solubility are due to hydration, the results under some assumptions can be used to calculate hydration numbers (H), i.e., the number of H2O molecules associated with each amino-acid solute molecule. The average values of hydration number (H¯) obtained at 25.0 °C are 15.3±1.5 for asparagine, 6.8±0.3 for cysteine, 11.5±1.1 for glutamine, 7.3±0.7 for histidine, 5.9±0.4 for isoleucine, 10.6±0.8 for methionine, 11.2±1.3 for serine, 7.7± 1.0 for threonine, and 6.6±0.6 for valine. We have also measured the temperature dependence of solubility L(T) from 5-40 °C for arginine, glycine, and proline, and obtained hydration numbers H¯(T) in this range. Between 25-40 °C, arginine has an H¯ near zero. This may be evidence for an attractive interaction between xenon and arginine molecules in aqueous solution.

  20. Photochemical abiotic synthesis of amino-acid precursors from simulated planetary atmospheres by vacuum ultraviolet light

    SciTech Connect

    Takahashi, Jun-ichi; Masuda, Hitomi; Kaneko, Takeo; Kobayashi, Kensei; Saito, Takeshi; Hosokawa, Teruo

    2005-07-15

    For the purpose of investigating the photon energy dependence of the photoinduced abiotic synthesis of organic molecules, gas mixtures that simulate typical planetary atmospheres, including a carbon source (CO or CH{sub 4}), a nitrogen source (N{sub 2} or NH{sub 3}), and H{sub 2}O, were irradiated with synchrotron radiation through a vacuum-ultraviolet transmitting window. Three kinds of window material, fused silica, synthetic quartz, and MgF{sub 2}, were used as a high-energy-cutting filter, whose absorption-edge energies are 6.4, 8.1, and 10.5 eV, respectively. Three types of gas mixture, Titan-type (CH{sub 4}-N{sub 2}-H{sub 2}O), comet-type (CO-NH{sub 3}-H{sub 2}O), and primitive-Earth-type (CO-N{sub 2}-H{sub 2}O), were irradiated with vacuum-ultraviolet photons in the three energy ranges. After the irradiation, amino-acid formation yields in the acid-hydrolyzed solution of the product were measured with a high-performance liquid chromatograph method. From the Titan- and comet-type mixtures, amino acids were detected by irradiation with photons lower than 8.1 eV. For both mixtures, the averaged quantum yields of glycine generation in the photon energy region of 7-10.5 eV were of the order of 10{sup -5}, which was larger by about one order than that in the region 5-8 eV. On the other hand, from the primitive-Earth-type mixture, amino-acid formation was difficult to detect even with irradiation as high as 10.5 eV, even though amino acids were generated in comparable yields from the Titan- and comet-type mixtures by irradiation with soft x rays or proton beam, whose energies are much higher. These results suggest that the vacuum ultraviolet light is a more effective energy source for the generation of the precursors of bioorganic compounds in extraterrestrial environments than in primitive-Earth atmosphere.

  1. Protein structure designability: The consequences of amino-acid alphabet and the underlying energy model

    NASA Astrophysics Data System (ADS)

    Buchler, Nicolas Emile G.

    2001-11-01

    It has been noted by scientists that certain native, protein structures occur more frequently than others in the Protein Data Bank. A variety of models have been developed to explain this phenomenon by considering protein structure "designability". A protein structure is more designable if a larger fraction of all possible sequences can fold into it. Such highly-designable structures are more likely to have been found and maintained through the process of evolution hence they are likely to be over-represented. Proteins are biopolymers and the key to designability lies with understanding the thermodynamic constraints of how a biologically relevant protein sequence folds into a native protein structure. We begin by discussing protein folding in the context of free energy landscapes and phase transitions. The role of protein evolution, critical transitions, such as "freezing" into the native state ( Tf), collapse into molten globules (Ttheta), and glassy phase transitions (Tg), folding-funnels, and free energy landscape measures is a well studied subject of protein folding both computationally and theoretically. In particular, the relationship between folding funnels and relevant phase transition temperatures (T f, Tg) can be related to free energy landscape measures, such as foldability F and energy gap Delta. Using the Random Energy Model, we analytically demonstrate the statistical relationship between F , Delta. Using simplified models of protein structure and interactions, we have explored the relationship between protein structure designability, foldability, interaction parameters, and amino-acid alphabet. We shed new light on which structures are expected to be highly designable, for which types of energy models (solvation or pair-contact), and why these structures are designable. Moreover, we can also understand why free energy landscape measures, such as foldability F and energy gap Delta, must be correlated to protein structure designability. We further

  2. Non-conservative characteristics of fluorescent tracers help to assess in-situ transport and attenuation of pesticides

    NASA Astrophysics Data System (ADS)

    Lange, Jens; Payraudeau, Sylvain; Imfeld, Gwenaël

    2016-04-01

    Traditionally, hydrological tracers are selected to behave as conservatively as possible, since most applications aim to investigate the transport of water or conservative solutes. Non-conservative tracer behavior is regarded as a limitation. However, the environmental behavior of organic pesticides is strictly non-conservative as their fate is affected by various processes, including sorption, photolysis and biochemical transformation in various environmental compartments. If tracers are used to study pesticides under these conditions, we believe that a paradigm shift is necessary: only a tracer that is affected by similar attenuation processes can realistically reproduce the overall behavior of a target pesticide. We present here two examples from two different environmental compartments: (i) agricultural soils and (ii) wetland systems. In both studies two organic fluorescent tracers (uranine, UR and sulforhodamine-B, SRB) and the salt tracer bromide (BR) were applied together with the chloroacetanilide herbicide S-metolachlor (S-MET). On an agricultural field, plot experiments were conducted under artificial and natural rainfall conditions. The use of BR overestimated both slow leaching and fast preferential transport of S-MET in the unsaturated zone, while UR/SRB were more realistic markers. Under artificial conditions, recovery rates of BR in a tile drain were twice as high as UR and one order of magnitude higher than SRB. Under natural conditions, BR concentrations in surface soils (0-1 cm) displayed larger variances during wetting and drying periods than UR, SRB and S-MET. BR also leached deeper (below 5 cm) than S-MET in the soil column. After 70 days, characteristic fluorescent peaks of UR and SRB gradually decreased in soil samples, while a new peak increased in another spectrum, which suggests the production of a potential transformation product. In two artificial wetland systems the impact of hydrological conditions (batch versus continuous-flow) on

  3. Structure and expression of the Drosophila ubiquitin-80-amino-acid fusion-protein gene.

    PubMed Central

    Barrio, R; del Arco, A; Cabrera, H L; Arribas, C

    1994-01-01

    In the fruitfly Drosophila, as in all eukaryotes examined so far, some ubiquitin-coding sequences appear fused to unrelated open reading frames. Two of these fusion genes have been previously described (the homologues of UBI1-UBI2 and UBI4 in yeast), and we report here the organization and expression of a third one, the DUb80 gene (the homologue of UBI3 in yeast). This gene encodes a ubiquitin monomer fused to an 80-amino-acid extension which is homologous with the ribosomal protein encoded by the UB13 gene. The 5' regulatory region of DUb80 shares common features with another ubiquitin fusion gene, DUb52, and with the ribosomal protein genes of Drosophila, Xenopus and mouse. We also find helix-loop-helix protein-binding sequences (E-boxes). The DUb80 gene is transcribed to a 0.9 kb mRNA which is particularly abundant under conditions of high protein synthesis, such as in ovaries and exponentially growing cells. Images Figure 3 Figure 4 PMID:8068011

  4. L-Aminoacid Oxidase from Bothrops leucurus Venom Induces Nephrotoxicity via Apoptosis and Necrosis

    PubMed Central

    Morais, Isabel C. O.; Pereira, Gustavo J. S.; Orzáez, M.; Jorge, Roberta J. B.; Bincoletto, Claudia; Toyama, Marcos H.; Monteiro, Helena S. A.; Smaili, Soraya S.; Pérez-Payá, Enrique; Martins, Alice M. C.

    2015-01-01

    Acute renal failure is a common complication caused by Bothrops viper envenomation. In this study, the nefrotoxicity of a main component of B. leucurus venom called L-aminoacid oxidase (LAAO-Bl) was evaluated by using tubular epithelial cell lines MDCK and HK-2 and perfused kidney from rats. LAAO-Bl exhibited cytotoxicity, inducing apoptosis and necrosis in MDCK and HK-2 cell lines in a concentration-dependent manner. MDCK apoptosis induction was accompanied by Ca2+ release from the endoplasmic reticulum, reactive oxygen species (ROS) generation and mitochondrial dysfunction with enhanced expression of Bax protein levels. LAAO-Bl induced caspase-3 and caspase-7 activation in both cell lines. LAAO-Bl (10 μg/mL) exerts significant effects on the isolated kidney perfusion increasing perfusion pressure and urinary flow and decreasing the glomerular filtration rate and sodium, potassium and chloride tubular transport. Taken together our results suggest that LAAO-Bl is responsible for the nephrotoxicity observed in the envenomation by snakebites. Moreover, the cytotoxic of LAAO-Bl to renal epithelial cells might be responsible, at least in part, for the nephrotoxicity observed in isolated kidney. PMID:26193352

  5. Partitioning of amino-acid analogues in a five-slab membrane model

    SciTech Connect

    Sengupta, D; Smith, Jeremy C; Ullmann, G. Matthias

    2008-09-01

    The positional preferences of the twenty amino-acid residues in a phospholipid bilayer are investigated by calculating the solvation free energy of the corresponding side chain analogues using a five-slab continuum electrostatic model. The side-chain analogues of the aromatic residues tryptophan and tyrosine are found to partition in the head-group region, due to compensation between the increase of the non-polar component of the solvation free energy at the boundary with the aqueous region and the decrease in the electrostatic component. The side chain analogue of phenylalanine differs from the other aromatic molecules by being able to partition in both the head-group region and the membrane core. This finding is consistent with experimental findings of the position of phenylalanine in membrane helices. Interestingly, the charged side-chain analogues of arginine and lysine are shown to prefer the head-group region in an orientation that allows the charged moiety to interact with the aqueous layer. The orientation adopted is similar to the 'snorkelling' effect seen in lysine and arginine residues in membrane helices. In contrast, the preference of the charged side-chain analogues of histidine (protonated) and aspartate (deprotonated) for the aqueous layer is shown to be due to a steep decrease in the electrostatic component of the solvation free energy at the boundary to the aqueous region. The calculations allow an understanding of the origins of side chain positioning in membranes and are thus useful in understanding membrane-protein:lipid thermodynamics.

  6. Substrate specificity and transport mechanism of amino-acid transceptor Slimfast from Aedes aegypti

    PubMed Central

    Boudko, Dmitri Y.; Tsujimoto, Hitoshi; Rodriguez, Stacy D.; Meleshkevitch, Ella A.; Price, David P.; Drake, Lisa L.; Hansen, Immo A.

    2015-01-01

    Anautogenous mosquitoes depend on vertebrate blood as nutrient source for their eggs. A highly efficient set of membrane transporters mediates the massive movement of nutrient amino acids between mosquito tissues after a blood meal. Here we report the characterization of the amino-acid transporter Slimfast (Slif) from the yellow-fever mosquito Aedes aegypti using codon-optimized heterologous expression. Slif is a well-known component of the target-of-rapamycin signalling pathway and fat body nutrient sensor, but its substrate specificity and transport mechanism were unknown. We found that Slif transports essential cationic and neutral amino acids with preference for arginine. It has an unusual dual-affinity mechanism with only the high affinity being Na+ dependent. Tissue-specific expression and blood meal-dependent regulation of Slif are consistent with conveyance of essential amino acids from gut to fat body. Slif represents a novel transport system and type of transceptor for sensing and transporting essential amino acids during mosquito reproduction. PMID:26449545

  7. Vitreous Substitutes

    PubMed Central

    Foster, William Joseph

    2008-01-01

    Modern vitreoretinal surgery is a young science. While tremendous developments have occurred in instrument design and technique since Machemer first described vitrectomy surgery in 1973[1], the application of advanced materials concepts to the development of intra-ocular compounds is a particularly exciting area of research. To date, the development of vitreous substitutes has played a significant role in enabling the dramatic and progressive improvement in surgical outcome, but perhaps no other area of research has the potential to further improve the treatment of retinal detachment and other retinal disorders. While prior research has focused solely upon the ability of a compound to re-attach the retina, future research should seek to enable the surgeon to inhibit the development of proliferative vitreoretinopathy and re-detachment, the integration of stem-cell therapies with surgical retina, long-term delivery of medications to the posterior segment, and the promotion of more rapid and complete visual rehabilitation. PMID:19343097

  8. Blood substitutes.

    PubMed

    Palmer, Andre F; Intaglietta, Marcos

    2014-07-11

    The toxic side effects of early generations of red blood cell substitutes have stimulated development of more safe and efficacious high-molecular-weight polymerized hemoglobins, poly(ethylene glycol)-conjugated hemoglobins, and vesicle-encapsulated hemoglobins. Unfortunately, the high colloid osmotic pressure and blood plasma viscosity of these new-generation materials limit their application to blood concentrations that, in general, are not sufficient for full restoration of oxygen-carrying and -delivery capacity. However, these materials may serve as oxygen therapeutics for treating tissues affected by ischemia and trauma, particularly when the therapeutics are coformulated with antioxidants. These new oxygen therapeutics also possess additional beneficial effects owing to their optimal plasma expansion properties, which induce systemic supraperfusion that increases endothelial nitric oxide production and improves tissue washout of metabolic wastes, further contributing to their therapeutic role.

  9. Evidence for non-conservative current-induced forces in the breaking of Au and Pt atomic chains.

    PubMed

    Sabater, Carlos; Untiedt, Carlos; van Ruitenbeek, Jan M

    2015-01-01

    This experimental work aims at probing current-induced forces at the atomic scale. Specifically it addresses predictions in recent work regarding the appearance of run-away modes as a result of a combined effect of the non-conservative wind force and a 'Berry force'. The systems we consider here are atomic chains of Au and Pt atoms, for which we investigate the distribution of break down voltage values. We observe two distinct modes of breaking for Au atomic chains. The breaking at high voltage appears to behave as expected for regular break down by thermal excitation due to Joule heating. However, there is a low-voltage breaking mode that has characteristics expected for the mechanism of current-induced forces. Although a full comparison would require more detailed information on the individual atomic configurations, the systems we consider are very similar to those considered in recent model calculations and the comparison between experiment and theory is very encouraging for the interpretation we propose. PMID:26734525

  10. Evidence for non-conservative current-induced forces in the breaking of Au and Pt atomic chains.

    PubMed

    Sabater, Carlos; Untiedt, Carlos; van Ruitenbeek, Jan M

    2015-01-01

    This experimental work aims at probing current-induced forces at the atomic scale. Specifically it addresses predictions in recent work regarding the appearance of run-away modes as a result of a combined effect of the non-conservative wind force and a 'Berry force'. The systems we consider here are atomic chains of Au and Pt atoms, for which we investigate the distribution of break down voltage values. We observe two distinct modes of breaking for Au atomic chains. The breaking at high voltage appears to behave as expected for regular break down by thermal excitation due to Joule heating. However, there is a low-voltage breaking mode that has characteristics expected for the mechanism of current-induced forces. Although a full comparison would require more detailed information on the individual atomic configurations, the systems we consider are very similar to those considered in recent model calculations and the comparison between experiment and theory is very encouraging for the interpretation we propose.

  11. Multicultural Challenges in Educational Policies within a Non-Conservative Scenario: The Case of the Emerging Reforms in Higher Education in Brazil

    ERIC Educational Resources Information Center

    Canen, Ana

    2005-01-01

    The article discusses the extent to which multiculturalism has had an impact in the emerging reforms in higher education in Brazil, against the backdrop of the rise of a new non-Conservative, Labour-oriented government whose political agenda is marked by a discursive stand against conservatism, neo-liberalism and neocolonialism. Building on a…

  12. ASC amino-acid transporter 2 (ASCT2) as a novel prognostic marker in non-small cell lung cancer

    PubMed Central

    Shimizu, K; Kaira, K; Tomizawa, Y; Sunaga, N; Kawashima, O; Oriuchi, N; Tominaga, H; Nagamori, S; Kanai, Y; Yamada, M; Oyama, T; Takeyoshi, I

    2014-01-01

    Background: ASC amino-acid transporter 2 (ASCT2) is a major glutamine transporter that has an essential role in tumour growth and progression. Although ASCT2 is highly expressed in various cancer cells, the clinicopathological significance of its expression in non-small cell lung cancer (NSCLC) remains unclear. Methods: One hundred and four patients with surgically resected NSCLC were evaluated as one institutional cohort. Tumour sections were stained by immunohistochemistry (IHC) for ASCT2, Ki-67, phospho-mTOR (mammalian target of rapamycin), and CD34 to assess the microvessel density. Two hundred and four patients with NSCLC were also validated by IHC from an independent cohort. Results: ASC amino-acid transporter 2 was expressed in 66% of patients, and was closely correlated with disease stage, lymphatic permeation, vascular invasion, CD98, cell proliferation, angiogenesis, and mTOR phosphorylation, particularly in patients with adenocarcinoma (AC). Moreover, two independent cohorts confirmed that ASCT2 was an independent marker for poor outcome in AC patients. Conclusions: ASC amino-acid transporter 2 expression has a crucial role in the metastasis of pulmonary AC, and is a potential molecular marker for predicting poor prognosis after surgery. PMID:24603303

  13. Theoretical Studies of Interactions between O-Phosphorylated and Standard Amino-Acid Side-Chain Models in Water

    PubMed Central

    Wiśniewska, Marta; Sobolewski, Emil; Ołdziej, Stanisław; Liwo, Adam; Scheraga, Harold A.; Makowski, Mariusz

    2015-01-01

    Phosphorylation is a common post-translational modification of the amino-acid side chains (serine, tyrosine, and threonine) that contain hydroxyl groups. The transfer of the negatively charged phosphate group from an ATP molecule to such amino-acid side chains leads to changes in the local conformations of proteins and the pattern of interactions with other amino-acid side-chains. A convenient characteristic of the side chain–side chain interactions in the context of an aqueous environment is the potential of mean force (PMF) in water. A series of umbrella-sampling molecular dynamic (MD) simulations with the AMBER force field were carried out for pairs of O-phosphorylated serine (pSer), threonine (pThr), and tyrosine, (pTyr) with natural amino acids in a TIP3P water model as a solvent at 298 K. The weighted-histogram analysis method was used to calculate the four-dimensional potentials of mean force. The results demonstrate that the positions and depths of the contact minima and the positions and heights of the desolvation maxima, including their dependence on the relative orientation depend on the character of the interacting pairs. More distinct minima are observed for oppositely charged pairs such as, e.g., O-phosphorylated side-chains and positively charged ones, such as the side-chains of lysine and arginine. PMID:26100791

  14. Simple, heart-smart substitutions

    MedlinePlus

    Coronary artery disease - heart smart substitutions; Atherosclerosis - heart smart substitutions; Cholesterol - heart smart substitutions; Coronary heart disease - heart smart substitutions; Healthy diet - heart ...

  15. Response theory of optical forces in two-port photonics systems: a simplified framework for examining conservative and non-conservative forces.

    PubMed

    Wang, Zheng; Rakich, Peter

    2011-10-24

    We extend the response theory of optical forces to general electromagnetic systems which can be treated as multi-port systems with multiple mechanical degrees of freedom. We demonstrate a fundamental link between the scattering properties of an optical system to its ability to produce conservative or non-conservative optical forces. Through the exploration of two nontrivial two-port systems, including an analytical Fabry-Perot interferometer and a more complex particle-in-a-waveguide structure, we show perfect agreement between the response theory and numerical first-principle calculations. We show that new insights into the origins of optical forces from the response theory provide clear means of understanding conservative and non-conservative forces in a regime where traditional gradient force picture fails.

  16. Glycine on silica: a model system for the study of adsorption and reactivity of aminoacids on extraterrestrial particulate

    NASA Astrophysics Data System (ADS)

    Lambert, J. F.; Stievano, L.; Costa, D.; Meng, M.; Lomenech, C.

    It is well known that a wide variety of organic compounds have been detected in extraterrestrial environments. Among them, simple aminoacids were often found in meteorites, comets and extraterrestrial particulates. Such materials, which are supposed to be formed and evolved in interstellar space, have therefore become of interest as possible sources for the development of Earth's first biosphere. In order to understand how organic matter can develop in such systems, and, in particular, how oligopeptides can be formed on the surface of such solids starting from simpler molecules, we decided to undertake a study of the adsorption and reactivity of simple aminoacids on finely divided oxide surfaces. Here we report, both from the theoretical and experimental point of view, on the mechanisms of formation of polypeptides starting from glycine, the simplest aminoacid, on the surface of silicon oxide. Glycine was adsorbed on the surface of well-characterised silica both from aqueous solutions under controlled pH and concentration, and from the gas phase. The adsorbed molecules were characterised using middle IR and UV-vis-NIR spectroscopies. The different preparation conditions resulted in different adsorption mechanisms at specific adsorption sites and different states of the adsorbed glycine in agreement with the DFT simulation data. The thermal reactivity of adsorbed/deposited glycine was then investigated by thermogravimetric analysis, in-situ diffuse reflectance IR spectroscopy, and thermoprogrammed desorption coupled with mass spectrometry. Adsorbed glycine molecules react to form peptide bonds at a temperature considerably lower than bulk crystalline α -glycine, mainly producing the cyclic dimer diketopiperazine. These findings are of relevance for the evaluation of prebiotic peptide synthesis scenarii.

  17. Synthetic amphibian peptides and short amino-acids derivatives against planktonic cells and mature biofilm of Providencia stuartii clinical strains.

    PubMed

    Ostrowska, Kinga; Kamysz, Wojciech; Dawgul, Małgorzata; Różalski, Antoni

    2014-01-01

    Over the last decade, the growing number of multidrug resistant strains limits the use of many of the currently available chemotherapeutic agents. Furthermore, bacterial biofilm, due to its complex structure, constitutes an effective barrier to conventional antibiotics. The in vitro activities of naturally occurring peptide (Citropin 1.1), chemically engineered analogue (Pexiganan), newly-designed, short amino-acid derivatives (Pal-KK-NH2, Pal-KKK-NH2, Pal-RRR-NH2) and six clinically used antimicrobial agents (Gatifloxacin, Ampicilin, Cefotaxime, Ceftriaxone, Cefuroxime and Cefalexin) were investigated against planktonic cells and mature biofilm of multidrug-resistant Providencia stuartii strains, isolated from urological catheters. The MICs, MBCs values were determined by broth microdilution technique. Inhibition of biofilm formation by antimicrobial agents as well as biofilm susceptibility assay were tested using a surrogate model based on the Crystal Violet method. The antimicrobial activity of amino-acids derivatives and synthetic peptides was compared to that of clinically used antibiotics. For planktonic cells, MICs of peptides and antibiotics ranged between 1 and 256 μg/ml and 256 and ≥ 2048 μg/ml, respectively. The MBCs values of Pexiganan, Citropin 1.1 and amino-acids derivatives were between 16 and 256 μg/ml, 64 and 256 μg/ml and 16 and 512 μg/ml, respectively. For clinically used antibiotics the MBCs values were above 2048 μg/ml. All of the tested peptides and amino-acids derivatives, showed inhibitory activity against P. stuartii biofilm formation, in relation to their concentrations. Pexiganan and Citropin 1.1 in concentration range 32 and 256 μg/ml caused both strong and complete suppression of biofilm formation. None of the antibiotics caused complete inhibition of biofilm formation process. The biofilm susceptibility assay verified the extremely poor antibiofilm activity of conventional antibiotics compared to synthetic peptides. The

  18. Synthetic amphibian peptides and short amino-acids derivatives against planktonic cells and mature biofilm of Providencia stuartii clinical strains.

    PubMed

    Ostrowska, Kinga; Kamysz, Wojciech; Dawgul, Małgorzata; Różalski, Antoni

    2014-01-01

    Over the last decade, the growing number of multidrug resistant strains limits the use of many of the currently available chemotherapeutic agents. Furthermore, bacterial biofilm, due to its complex structure, constitutes an effective barrier to conventional antibiotics. The in vitro activities of naturally occurring peptide (Citropin 1.1), chemically engineered analogue (Pexiganan), newly-designed, short amino-acid derivatives (Pal-KK-NH2, Pal-KKK-NH2, Pal-RRR-NH2) and six clinically used antimicrobial agents (Gatifloxacin, Ampicilin, Cefotaxime, Ceftriaxone, Cefuroxime and Cefalexin) were investigated against planktonic cells and mature biofilm of multidrug-resistant Providencia stuartii strains, isolated from urological catheters. The MICs, MBCs values were determined by broth microdilution technique. Inhibition of biofilm formation by antimicrobial agents as well as biofilm susceptibility assay were tested using a surrogate model based on the Crystal Violet method. The antimicrobial activity of amino-acids derivatives and synthetic peptides was compared to that of clinically used antibiotics. For planktonic cells, MICs of peptides and antibiotics ranged between 1 and 256 μg/ml and 256 and ≥ 2048 μg/ml, respectively. The MBCs values of Pexiganan, Citropin 1.1 and amino-acids derivatives were between 16 and 256 μg/ml, 64 and 256 μg/ml and 16 and 512 μg/ml, respectively. For clinically used antibiotics the MBCs values were above 2048 μg/ml. All of the tested peptides and amino-acids derivatives, showed inhibitory activity against P. stuartii biofilm formation, in relation to their concentrations. Pexiganan and Citropin 1.1 in concentration range 32 and 256 μg/ml caused both strong and complete suppression of biofilm formation. None of the antibiotics caused complete inhibition of biofilm formation process. The biofilm susceptibility assay verified the extremely poor antibiofilm activity of conventional antibiotics compared to synthetic peptides. The

  19. Prognostic significance of amino-acid transporter expression (LAT1, ASCT2, and xCT) in surgically resected tongue cancer

    PubMed Central

    Toyoda, M; Kaira, K; Ohshima, Y; Ishioka, N S; Shino, M; Sakakura, K; Takayasu, Y; Takahashi, K; Tominaga, H; Oriuchi, N; Nagamori, S; Kanai, Y; Oyama, T; Chikamatsu, K

    2014-01-01

    Background: Amino-acid transporters are necessary for the tumour cell growth and survival, and have a crucial role in the development and invasiveness of cancer cells. But, it remains unclear about the prognostic significance of L-type amino-acid transporter 1 (LAT1), system ASC amino-acid transporter-2 (ASCT2), and xCT expression in patients with tongue cancer. We conducted the clinicopathological study to investigate the protein expression of these amino-acid transporters in tongue cancer. Methods: Eighty-five patients with surgically resected tongue cancer were evaluated. Tumour sections were stained by immunohistochemistry for LAT1, ASCT2, xCT, 4F2hc/CD98hc (4F2hc), Ki-67, and microvessel density (MVD) determined by CD34, and p53. Results: L-type amino-acid transporter 1 and 4F2hc were highly expressed in 61% (52 out of 85) and 45% (38 out of 47), respectively. ASC amino-acid transporter-2 and xCT were positively expressed in 59% (50 out of 85) and 21% (18 out of 85), respectively. The expression of both LAT1 and ASCT2 was significantly associated with disease staging, lymph-node metastasis, lymphatic permeation, 4F2hc expression and cell proliferation (Ki-67). xCT expression indicated a significant association with advanced stage and tumour factor. By univariate analysis, disease staging, lymphatic permeation, vascular invasion, LAT1, ASCT2, 4F2hc, and Ki-67 had a significant relationship with overall survival. Multivariate analysis confirmed that LAT1 was an independent prognostic factor for predicting poor prognosis. Conclusions: L-type amino-acid transporter 1 and ASCT2 can serve as a significant prognostic factor for predicting worse outcome after surgical treatment and may have an important role in the development and aggressiveness of tongue cancer. PMID:24762957

  20. Nucleophilic Aromatic Substitution.

    ERIC Educational Resources Information Center

    Avila, Walter B.; And Others

    1990-01-01

    Described is a microscale organic chemistry experiment which demonstrates one feasible route in preparing ortho-substituted benzoic acids and provides an example of nucleophilic aromatic substitution chemistry. Experimental procedures and instructor notes for this activity are provided. (CW)

  1. A single amino-acid substitution allows endo-polygalacturonase of Fusarium verticillioides to acquire recognition by PGIP2 from Phaseolus vulgaris.

    PubMed

    Benedetti, Manuel; Andreani, Federico; Leggio, Claudia; Galantini, Luciano; Di Matteo, Adele; Pavel, Nicolae Viorel; De Lorenzo, Giulia; Cervone, Felice; Federici, Luca; Sicilia, Francesca

    2013-01-01

    Polygalacturonases (PGs) are secreted by phytopathogenic fungi to degrade the plant cell wall homogalacturonan during plant infection. To counteract Pgs, plants have evolved polygalacturonase-inhibiting proteins (PGIPs) that slow down fungal infection and defend cell wall integrity. PGIPs favour the accumulation of oligogalacturonides, which are homogalacturonan fragments that act as endogenous elicitors of plant defence responses. We have previously shown that PGIP2 from Phaseolus vulgaris (PvPGIP2) forms a complex with PG from Fusarium phyllophilum (FpPG), hindering the enzyme active site cleft from substrate. Here we analyse by small angle X-ray scattering (SAXS) the interaction between PvPGIP2 and a PG from Colletotrichum lupini (CluPG1). We show a different shape of the PG-PGIP complex, which allows substrate entry and provides a structural explanation for the different inhibition kinetics exhibited by PvPGIP2 towards the two isoenzymes. The analysis of SAXS structures allowed us to investigate the basis of the inability of PG from Fusarium verticilloides (FvPG) to be inhibited by PvPGIP2 or by any other known PGIP. FvPG is 92.5% identical to FpPG, and we show here, by both loss- and gain-of-function mutations, that a single amino acid site acts as a switch for FvPG recognition by PvPGIP2.

  2. Restoration of the contact surface in FORCE-type centred schemes II: Non-conservative one- and two-layer two-dimensional shallow water equations

    NASA Astrophysics Data System (ADS)

    Canestrelli, Alberto; Toro, Eleuterio F.

    2012-10-01

    Recently, a non-conservative well-balanced FORCE-type scheme has been proposed for solving multidimensional non-conservative equations such as the shallow water equations [4], the two-fluid flow model of Pitman and Le and the two- and three-dimensional Baer-Nunziato equations for compressible multiphase flows [17]. In the present paper the original scheme is first rewritten in a suitable form that allows easy manipulation of numerical fluxes. We then propose a modified scheme that provides a better resolution of contact waves for both one-layer and two-layer shallow water models. The improvement is particularly evident when an additional equation is solved for a passive solute. In this case, the original scheme does not satisfy the C-property for a uniformly distribute tracer, whereas the modified scheme provides a solution that is exact up to machine precision. Moreover, the modified scheme better resolves contact discontinuities, with an accuracy close to the one provided by a fully-upwind non-conservative ROE-type scheme accounting for the complete wave structure. When higher orders are achieved, the difference in accuracy between the various schemes is less pronounced. Moreover, the capability of the two-dimensional scheme to capture steady states is analyzed for both straight and meandering non-flat channels with non-zero friction, and for both one-layer and two-layer equations. Whereas the original first order FORCE scheme is able to correctly reproduce the longitudinal profile in the case of a straight channel even on a coarse mesh, when the channel is strongly meandering a modification of the scheme is necessary, otherwise a very refined mesh and a very high order of accuracy are needed, with a notable increase of computational time.

  3. An Evolutionary Strategy for All-Atom Folding of the 60-Amino-Acid Bacterial Ribosomal Protein L20

    PubMed Central

    Schug, A.; Wenzel, W.

    2006-01-01

    We have investigated an evolutionary algorithm for de novo all-atom folding of the bacterial ribosomal protein L20. We report results of two simulations that converge to near-native conformations of this 60-amino-acid, four-helix protein. We observe a steady increase of “native content” in both simulated ensembles and a large number of near-native conformations in their final populations. We argue that these structures represent a significant fraction of the low-energy metastable conformations, which characterize the folding funnel of this protein. These data validate our all-atom free-energy force field PFF01 for tertiary structure prediction of a previously inaccessible structural family of proteins. We also compare folding simulations of the evolutionary algorithm with the basin-hopping technique for the Trp-cage protein. We find that the evolutionary algorithm generates a dynamic memory in the simulated population, which leads to faster overall convergence. PMID:16565067

  4. Induced europium CPL for the selective signalling of phosphorylated amino-acids and O-phosphorylated hexapeptides.

    PubMed

    Neil, Emily R; Fox, Mark A; Pal, Robert; Parker, David

    2016-05-17

    Two bright, europium(iii) complexes based on an achiral heptadentate triazacyclononane ligand bearing two strongly absorbing chromophores have been evaluated for the selective emission and CPL signalling of various chiral O-phosphono-anions. Binding of O-phosphono-Ser and Thr gives rise to a strong induced CPL signature and a favoured Δ complex configuration is adopted. A similarly large induced CPL signal arises when [Eu·](2+) binds to lysophosphatidic acid (LPA), where the strong binding (log K 5.25 (295 K)) in methanol allowed its detection over the range 5 to 40 μM. Strong and chemoselective binding to the phosphorylated amino-acid residues was also observed with a set of four structurally related hexapeptides: in one case, the sign of the gem value in the ΔJ = 1 transition allowed differentiation between the binding to O-P-Ser and O-P-Tyr residues. PMID:27109001

  5. Amino-acid mutations to extend the biological half-life of a therapeutically valuable mutant of human butyrylcholinesterase.

    PubMed

    Fang, Lei; Hou, Shurong; Xue, Liu; Zheng, Fang; Zhan, Chang-Guo

    2014-05-01

    Cocaine is a widely abused and addictive drug without an FDA-approved medication. Our recently designed and discovered cocaine hydrolase, particularly E12-7 engineered from human butyrylcholinesterase (BChE), has the promise of becoming a valuable cocaine abuse treatment. An ideal anti-cocaine therapeutic enzyme should have not only a high catalytic efficiency against cocaine, but also a sufficiently long biological half-life. However, recombinant human BChE and the known BChE mutants have a much shorter biological half-life compared to the native human BChE. The present study aimed to extend the biological half-life of the cocaine hydrolase without changing its high catalytic activity against cocaine. Our strategy was to design possible amino-acid mutations that can introduce cross-subunit disulfide bond(s) and, thus, change the distribution of the oligomeric forms and extend the biological half-life. Three new BChE mutants (E364-532, E377-516, and E535) were predicted to have a more stable dimer structure with the desirable cross-subunit disulfide bond(s) and, therefore, a different distribution of the oligomeric forms and a prolonged biological half-life. The rational design was followed by experimental tests in vitro and in vivo, confirming that the rationally designed new BChE mutants, i.e. E364-532, E377-516, and E535, indeed had a remarkably different distribution of the oligomeric forms and prolonged biological half-life in rats from ∼7 to ∼13h without significantly changing the catalytic activity against (-)-cocaine. This is the first demonstration that rationally designed amino-acid mutations can significantly prolong the biological half-life of a high-activity enzyme without significantly changing the catalytic activity.

  6. Managing Substitute Teaching.

    ERIC Educational Resources Information Center

    Jones, Kevin R.

    1999-01-01

    This news brief presents information on managing substitute teaching. The information is based on issues discussed at a summit meeting which included public school administrators and personnel directors from around the nation. The main topics of concern focused around four core components related to the management of substitute teaching:…

  7. Apple Aminoacid Profile and Yeast Strains in the Formation of Fusel Alcohols and Esters in Cider Production.

    PubMed

    Eleutério Dos Santos, Caroline Mongruel; Pietrowski, Giovana de Arruda Moura; Braga, Cíntia Maia; Rossi, Márcio José; Ninow, Jorge; Machado Dos Santos, Tâmisa Pires; Wosiacki, Gilvan; Jorge, Regina Maria Matos; Nogueira, Alessandro

    2015-06-01

    The amino acid profile in dessert apple must and its effect on the synthesis of fusel alcohols and esters in cider were established by instrumental analysis. The amino acid profile was performed in nine apple musts. Two apple musts with high (>150 mg/L) and low (<75 mg/L) nitrogen content, and four enological yeast strains, were used in cider fermentation. The aspartic acid, asparagine and glutamic acid amino acids were the majority in all the apple juices, representing 57.10% to 81.95%. These three amino acids provided a high consumption (>90%) during fermentation in all the ciders. Principal component analysis (PCA) explained 81.42% of data variability and the separation of three groups for the analyzed samples was verified. The ciders manufactured with low nitrogen content showed sluggish fermentation and around 50% less content of volatile compounds (independent of the yeast strain used), which were mainly 3-methyl-1-butanol (isoamyl alcohol) and esters. However, in the presence of amino acids (asparagine, aspartic acid, glutamic acid and alanine) there was a greater differentiation between the yeasts in the production of fusel alcohols and ethyl esters. High contents of these aminoacids in dessert apple musts are essential for the production of fusel alcohols and most of esters by aromatic yeasts during cider fermentation. PMID:25920613

  8. A leptin derived 30-amino-acid peptide modified pegylated poly-L-lysine dendrigraft for brain targeted gene delivery.

    PubMed

    Liu, Yang; Li, Jianfeng; Shao, Kun; Huang, Rongqin; Ye, Liya; Lou, Jinning; Jiang, Chen

    2010-07-01

    The blood-brain barrier is the major obstacle that prevents diagnostic and therapeutic drugs being delivered to the central nervous systems in order to exert their effects. Specific ligand-receptor binding mediated endocytosis is one of the possible strategies to cross this barrier. A 30-amino-acid peptide (leptin30) derived from an endogenic hormone-leptin is exploited as brain-targeting ligand as it is reported to possess the same brain accumulation efficiency after intravenous injection. Dendrigraft poly-L-lysine (DGL) is used as non-viral gene vector in this study. DGL-PEG-Leptin30 was complexed with plasmid DNA yielding nanoparticles (NPs). The cellular uptake characteristic and mechanism were explored in brain capillary endothelial cells (BCECs) which express leptin receptors. Furthermore, brain parenchyma microglia cells such as BV-2 cells expressing leptin receptors could promote ligand-receptor mediated endocytosis leading to enhanced gene transfection ability of DGL-PEG-Leptin30/DNA NPs. The targeted NPs were proved to be transported across in vitro BBB model effectively and accumulate more in brains after i.v. resulting in a relatively high gene transfection efficiency both in vitro and in vivo. Besides, the NPs showed low cytotoxicity after in vitro transfection. Thus, DGL-PEG-Leptin30 provides a safe and noninvasive approach for the delivery of gene across the blood-brain barrier.

  9. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  10. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  11. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  12. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  13. 40 CFR 721.981 - Substituted naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... naphthalenyl-substituted azonaphthol chromium complex. 721.981 Section 721.981 Protection of Environment...-substituted naphthalenyl-substituted azonaphthol chromium complex. (a) Chemical substance and significant new... naphtholoazo-substituted naphthalenyl-substituted azonaphthol chromium complex (PMN P-93-1631) is subject...

  14. Synthesis of substituted pyrazines

    DOEpatents

    Pagoria, Philip F.; Zhang, Mao Xi

    2016-10-04

    A method for synthesizing a pyrazine-containing material according to one embodiment includes contacting an iminodiacetonitrile derivative with a base and a reagent selected from a group consisting of hydroxylamine, a hydroxylamine salt, an aliphatic primary amine, a secondary amine, an aryl-substituted alkylamine a heteroaryl-substituted alkyl amine, an alcohol, an alkanolamine and an aryl alcoholamine. Additional methods and several reaction products are presented. ##STR00001##

  15. The amino-acid sequence of the alpha-crystallin A chains of red kangaroo and Virginia opossum.

    PubMed

    De Jong, W W; Terwindt, E C

    1976-08-16

    The amino acid sequence of the A chain of the eye lens protein alpha-crystallin from the red kangaroo (Macropus rufus) was completely determined by manual Edman degradation of tryptic, thermolytic and cyanogen bromide peptides. The sequence of the alpha-crystallin A chain from the Virginia opossum (Didelphis marsupialis) was deduced from amino acid analyses and partial Edman degradation of peptides. The 173-residue A chains of kangaroo and opossum differ in six positions, whereas comparison with the bovine alpha-crystallin A chain reveals 17 and 22 substitutions, respectively. Most substitutions occur in the COOH-terminal part of the chain.

  16. The 30-Amino-Acid Deletion in the Nsp2 of Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus Emerging in China Is Not Related to Its Virulence▿

    PubMed Central

    Zhou, Lei; Zhang, Jialong; Zeng, Jingwen; Yin, Shuoyan; Li, Yanhua; Zheng, Linying; Guo, Xin; Ge, Xinna; Yang, Hanchun

    2009-01-01

    During the past 2 years, an atypical clinical outbreak, caused by a highly pathogenic porcine reproductive and respiratory syndrome virus (PRRSV) with a unique 30-amino-acid deletion in its Nsp2-coding region, was pandemic in China. In this study, we generated four full-length infectious cDNA clones: a clone of the highly virulent PRRSV strain JXwn06 (pWSK-JXwn), a clone of the low-virulence PRRSV strain HB-1/3.9 (pWSK-HB-1/3.9), a chimeric clone in which the Nsp2 region containing the 30-amino-acid deletion was replaced by the corresponding region of the low-virulence PRRSV strain HB-1/3.9 (pWSK-JXwn-HB1nsp2), and a mutated HB-1/3.9 clone with the same deletion in Nsp2 as JXwn06 (pWSK-HB1-ND30). We also investigated the pathogenicities of the rescued viruses (designated RvJXwn, RvJXwn-HB1nsp2, RvHB-1/3.9, and RvHB1-ND30, respectively) in specific-pathogen-free piglets in order to determine the role of the 30-amino-acid deletion in the virulence of the highly pathogenic PRRSV. All the rescued viruses could replicate stably in MARC-145 cells. Our findings indicated that RvJXwn-HB1nsp2 retained high virulence for piglets, like RvJXwn and the parental virus JXwn06, although the survival time of piglets infected with RvJXwn-HB1nsp2 was obviously prolonged. RvHB1-ND30 exhibited low virulence for piglets, like RvHB-1/3.9 and the parental virus HB-1/3.9. Therefore, we conclude that the 30-amino-acid deletion is not related to the virulence of the highly pathogenic PRRSV emerging in China. PMID:19244318

  17. Response of Fe-S cluster assembly machinery of Escherichia coli to mechanical stress in a model of amino-acid crystal fermentation.

    PubMed

    Okutani, Satoshi; Iwai, Takayoshi; Iwatani, Shintaro; Matsuno, Kiyoshi; Takahashi, Yasuhiro; Hase, Toshiharu

    2015-09-01

    During amino-acid crystal fermentation, mechanical stress on bacterial cells caused by crystal collision often impacts negatively on bacterial growth and amino-acid production. When Escherichia coli cells were cultivated under mechanical stress of polyvinyl chloride particles as a model of the crystal fermentation, activities of iron-sulfur (Fe-S) cluster-containing enzymes were apparently decreased. Based on an assumption that function of Fe-S cluster assembly machinery would be elevated to recover the enzyme activities in such stressed cells, we analyzed levels of various components of Fe-S cluster assembly machinery by western blotting. It was found that the expression of HscA, a chaperon component of the machinery, was up-regulated and that shorter forms of HscA with the N-terminal region truncated were accumulated, suggesting an important role of HscA against the mechanical stress. An overexpression of HscA gene in E. coli cells gave a positive effect on rescue of the stress-induced decrease of the activity of Fe-S cluster-containing enzyme. These results may provide a new strategy to alleviate the mechanical stress during the amino-acid crystal fermentation. PMID:25682519

  18. Response of Fe-S cluster assembly machinery of Escherichia coli to mechanical stress in a model of amino-acid crystal fermentation.

    PubMed

    Okutani, Satoshi; Iwai, Takayoshi; Iwatani, Shintaro; Matsuno, Kiyoshi; Takahashi, Yasuhiro; Hase, Toshiharu

    2015-09-01

    During amino-acid crystal fermentation, mechanical stress on bacterial cells caused by crystal collision often impacts negatively on bacterial growth and amino-acid production. When Escherichia coli cells were cultivated under mechanical stress of polyvinyl chloride particles as a model of the crystal fermentation, activities of iron-sulfur (Fe-S) cluster-containing enzymes were apparently decreased. Based on an assumption that function of Fe-S cluster assembly machinery would be elevated to recover the enzyme activities in such stressed cells, we analyzed levels of various components of Fe-S cluster assembly machinery by western blotting. It was found that the expression of HscA, a chaperon component of the machinery, was up-regulated and that shorter forms of HscA with the N-terminal region truncated were accumulated, suggesting an important role of HscA against the mechanical stress. An overexpression of HscA gene in E. coli cells gave a positive effect on rescue of the stress-induced decrease of the activity of Fe-S cluster-containing enzyme. These results may provide a new strategy to alleviate the mechanical stress during the amino-acid crystal fermentation.

  19. A New Pro-Prodrug Aminoacid-Based for Trans-Ferulic Acid and Silybin Intestinal Release

    PubMed Central

    Trombino, Sonia; Ferrarelli, Teresa; Cassano, Roberta

    2014-01-01

    The aim of this work was the preparation and characterization of a pro-prodrug able to simultaneously transport silybin, a drug possessing various pharmacological effects, and trans-ferulic acid, a known antioxidant. More specifically, l-phenylalanine-N-(4-hydroxy-3-methoxy-phenyl) prop-2-en-O-(2R,3R)-3,5,7-trihydroxy-2-((2R,3R)-3-(4-hydroxy-3-methoxyphenyl)-2-(hydroxymethyl)-2,3-dihydro-benzo-(1,4)-dioxin-6-yl)croman-4-one was synthesized by using the aminoacid l-phenylalanine (l-Phe) as carrier. Indeed, l-Phe is characterized by an intrinsic chemical reactivity due to the presence of an amino group, placed on the chiral center, and of a carboxylic group. The synthesis has been characterized first by adding silybin by means of carboxylic group and then, with the aim to confer antioxidant properties to this new carrier, by linking trans-ferulic acid to l-Phe via amino group. The so obtained derivative was then characterized by FT-IR, and 1H-NMR spectroscopies. Furthermore, its ability to inhibit lipid peroxidation induced by tert-butyl hydroperoxide in rat liver microsomes, was evaluated. The 1,1-diphenyl-2-picrylhydrazyl radical-scavenging effect, was also assessed. The release of silybin and trans-ferulic acid was determined in simulated gastric and intestinal fluids over the time. The results showed that the covalent bond between both (i) silybin; or (ii) trans-ferulic acid and the amino acid was degraded by enzymatic reactions. In addition, the pro-prodrug, showed strong antioxidant and scavenger activities. Due to these properties, this new pro-prodrug could be applied for the treatment of intestinal pathologies and it might improve the therapeutic potential of silybin which is strongly limited by its low solubility. PMID:25062426

  20. Measurement scheme for a ground-state parity non-conserving (PNC) measurement in a cesium atomic beam via two-pathway coherent control

    NASA Astrophysics Data System (ADS)

    Choi, Jungu; Elliott, Dan; Elliott's Lab Team

    2016-05-01

    We present a detailed analysis of an experimental setup for parity non-conserving (PNC) measurements in a cesium atomic beam. We employ a parallel-plate transmission line (PPTL) structure and highly reflective cylindrical mirrors to form a microwave cavity resonator to excite the PNC transitions in the cesium hyperfine ground states. In addition, a variable external dc field is applied to observe the Stark-induced transition, which would interfere with the PNC transition as the dc field amplitude changes. Finally, strong Raman lasers are used to excite the ground hyperfine transition. The Raman fields interfere with the weak transitions, and by varying the phase difference between the Raman fields and the microwave fields, we would infer the weak transition amplitudes from the signal modulation. The experimental setup requires maintaining coherent phase relations between all fields, well-characterized dc and rf field patterns, the two co-propagating Raman lasers, and suppression of the magnetic dipole contribution. Our analysis of the field modes supported by the PPTL structure indicates that with a moderate rf power and a few tens of seconds of data collection time, the PNC measurement of less than 3% uncertainty would be feasible.

  1. Well-balanced high-order centred schemes for non-conservative hyperbolic systems. Applications to shallow water equations with fixed and mobile bed

    NASA Astrophysics Data System (ADS)

    Canestrelli, Alberto; Siviglia, Annunziato; Dumbser, Michael; Toro, Eleuterio F.

    2009-06-01

    This paper concerns the development of high-order accurate centred schemes for the numerical solution of one-dimensional hyperbolic systems containing non-conservative products and source terms. Combining the PRICE-T method developed in [Toro E, Siviglia A. PRICE: primitive centred schemes for hyperbolic system of equations. Int J Numer Methods Fluids 2003;42:1263-91] with the theoretical insights gained by the recently developed path-conservative schemes [Castro M, Gallardo J, Parés C. High-order finite volume schemes based on reconstruction of states for solving hyperbolic systems with nonconservative products applications to shallow-water systems. Math Comput 2006;75:1103-34; Parés C. Numerical methods for nonconservative hyperbolic systems: a theoretical framework. SIAM J Numer Anal 2006;44:300-21], we propose the new PRICE-C scheme that automatically reduces to a modified conservative FORCE scheme if the underlying PDE system is a conservation law. The resulting first-order accurate centred method is then extended to high order of accuracy in space and time via the ADER approach together with a WENO reconstruction technique. The well-balanced properties of the PRICE-C method are investigated for the shallow water equations. Finally, we apply the new scheme to the shallow water equations with fix bottom topography and with variable bottom solving an additional sediment transport equation.

  2. The substitutability of reinforcers.

    PubMed

    Green, Leonard; Freed, Debra E

    1993-07-01

    Substitutability is a construct borrowed from microeconomics that describes a continuum of possible interactions among the reinforcers in a given situation. Highly substitutable reinforcers, which occupy one end of the continuum, are readily traded for each other due to their functional similarity. Complementary reinforcers, at the other end of the continuum, tend to be consumed jointly in fairly rigid proportion, and therefore cannot be traded for one another except to achieve that proportion. At the center of the continuum are reinforcers that are independent with respect to each other; consumption of one has no influence on consumption of another. Psychological research and analyses in terms of substitutability employ standard operant conditioning paradigms in which humans and nonhumans choose between alternative reinforcers. The range of reinforcer interactions found in these studies is more readily accommodated and predicted when behavior-analytic models of choice consider issues of substitutability. New insights are gained into such areas as eating and drinking, electrical brain stimulation, temporal separation of choice alternatives, behavior therapy, drug use, and addictions. Moreover, the generalized matching law (Baum, 1974) gains greater explanatory power and comprehensiveness when measures of substitutability are included. PMID:16812696

  3. The substitutability of reinforcers

    PubMed Central

    Green, Leonard; Freed, Debra E.

    1993-01-01

    Substitutability is a construct borrowed from microeconomics that describes a continuum of possible interactions among the reinforcers in a given situation. Highly substitutable reinforcers, which occupy one end of the continuum, are readily traded for each other due to their functional similarity. Complementary reinforcers, at the other end of the continuum, tend to be consumed jointly in fairly rigid proportion, and therefore cannot be traded for one another except to achieve that proportion. At the center of the continuum are reinforcers that are independent with respect to each other; consumption of one has no influence on consumption of another. Psychological research and analyses in terms of substitutability employ standard operant conditioning paradigms in which humans and nonhumans choose between alternative reinforcers. The range of reinforcer interactions found in these studies is more readily accommodated and predicted when behavior-analytic models of choice consider issues of substitutability. New insights are gained into such areas as eating and drinking, electrical brain stimulation, temporal separation of choice alternatives, behavior therapy, drug use, and addictions. Moreover, the generalized matching law (Baum, 1974) gains greater explanatory power and comprehensiveness when measures of substitutability are included. PMID:16812696

  4. Formation of wormlike micelle in a mixed amino-acid based anionic surfactant and cationic surfactant systems.

    PubMed

    Shrestha, Rekha Goswami; Shrestha, Lok Kumar; Aramaki, Kenji

    2007-07-01

    Formation of wormlike micelles in mixed anionic/cationic system without the addition of any salt has been studied. Amino-acid based anionic surfactant N-dodecylglutamic acid (LAD), which is practically immiscible with water at 25 degrees C upon neutralization by 2,2',2''-nitrilotriethanol (TEA) forms small micellar aggregates and the solution behaves like a Newtonian fluid. The rheological behavior of LAD/water/hexadecyltrimethylammonium bromide (CTAB) and LAD/water/dodecyltrimethylammonium bromide (DTAB) systems were investigated at different degrees of neutralization of the LAD depending on the concentration of the cationic surfactants and on temperature. Addition of CTAB to the dilute aqueous solution of the LAD-TEA-x (the neutralized product, where x represents the mole ratio of TEA) causes one dimensional micellar growth. After certain concentration the elongated micelles entangle forming a rigid network of viscoelastic wormlike micelles. Thus formed viscoelastic solutions follow Maxwellian behavior over a wide range of frequency and thus are considered to consist of transient network of wormlike micelles. By varying the degree of neutralization from 1:1 via 1:1.5 to 1:2 (molar ratio) phase and rheological behavior were modified in that the highly viscous region of viscoelastic wormlike micelles shifted to higher CTAB concentrations and no maxima in the zero-shear viscosity could be observed for the higher degree of neutralization of the LAD (1:1.5 and 1:2). However, the obtained rheological parameters showed scaling relationships that were consistent with the living polymer model. The zero-shear viscosity decays exponentially with temperature following Arrhenius behavior. The flow activation energy calculated from the Arrhenius plot is very close to the value reported for the typical wormlike micellar solution. In contrast to CTAB no formation of viscoelastic wormlike micelles could be observed with DTAB, although, the solution viscosity increases. The

  5. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  6. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  7. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  8. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  9. 40 CFR 721.10126 - Alkyl amino substituted triazine amino substituted benezenesulfonic acid reaction product with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo substituted phenyl azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato azo... substituted triazine amino substituted benezenesulfonic acid reaction product with naphthalenesulfonato...

  10. The Age of Substitutability

    ERIC Educational Resources Information Center

    Goeller, H. E.; Weinberg, Alvin M.

    1976-01-01

    Dwindling mineral resources might cause a shift from nonrenewable resources to renewable resources and inexhaustible elements such as iron and aluminum. Alternative energy sources such as breeder, fusion, solar, and geothermal power must be developed for production and recycling of materials. Substitution and, hence, living standards ultimately…

  11. Performing Substitute Teaching

    ERIC Educational Resources Information Center

    Bletzer, Keith V.

    2010-01-01

    Formal education is both a right and an obligation bestowed on young people in most all nations of the world. Teachers (adults) and students (youth) form a co-present dyadic contract that must be maintained within the classroom. Substitute teachers fill a role in sustaining the integrity of this teacher-student link, whenever teachers are absent.…

  12. Screening Substitute Teachers.

    ERIC Educational Resources Information Center

    Kakkuri, Mark

    2000-01-01

    The screening process a school district uses in hiring substitute teachers is critical to striking a balance between required qualifications and immediate need. Typically, screening involves at least one of the following: pre-screening, paper and pencil screening, interviews, and background checks, each of which is used to different degrees…

  13. Nanoflakes of an aminoacid-based chiral coordination polymer: Synthesis, optical and electrochemical properties, and application in electrochemical sensing of H{sub 2}O{sub 2}

    SciTech Connect

    Zhou, Bo; Liang, Li-Mei; Yao, Jie

    2015-03-15

    Nanoflakes of an aminoacid-based chiral coordination polymer (CP), [Cu{sub 2}(tyr){sub 2}(bipy)]{sub n}, were synthesized successfully in the presence of surfactant, as evidenced by the XRD and SEM results. UV–vis absorption spectrometry and fluorescence spectrometry were used to investigate the optical properties of the CP, which was found to be mainly attributed to the ligands, while the forming of the CP caused only slight change. On the other hand, Cu(II) ions acted as electrocatalytic active sites of the CP, as evidenced by cyclic voltammetry. The CP also showed good performance in the electrochemical sensing of H{sub 2}O{sub 2}: sensitivity of 85.6 mA mol{sup −1} L cm{sup −2}, linear range of 1.0×10{sup −5}–7.69×10{sup −3} M, detection limit of 1.0×10{sup −5} M (S/N=3), and fast response in mere 5 s. - Graphical abstract: Nanoflakes of an aminoacid-based chiral coordination polymer (CP), [Cu{sub 2}(tyr){sub 2}(bipy)]{sub n}, were synthesized successfully and showed good performance in the electrochemical sensing of H{sub 2}O{sub 2}. - Highlights: • Synthesis of nanoflakes of an aminoacid-based chiral CP. • Optical and electrochemical properties resulting respectively from ligands and Cu{sup II}. • Good performance in enzyme-free electrochemical sensing of H{sub 2}O{sub 2}.

  14. The 1.9 A Structure of the Branched-Chain Amino-Acid Transaminase (IlvE) from Mycobacterium tuberculosis

    SciTech Connect

    Tremblay, L.; Blanchard, J

    2009-01-01

    Unlike mammals, bacteria encode enzymes that synthesize branched-chain amino acids. The pyridoxal 5'-phosphate-dependent transaminase performs the final biosynthetic step in these pathways, converting keto acid precursors into {alpha}-amino acids. The branched-chain amino-acid transaminase from Mycobacterium tuberculosis (MtIlvE) has been crystallized and its structure has been solved at 1.9 {angstrom} resolution. The MtIlvE monomer is composed of two domains that interact to form the active site. The biologically active form of IlvE is a homodimer in which each monomer contributes a substrate-specificity loop to the partner molecule. Additional substrate selectivity may be imparted by a conserved N-terminal Phe30 residue, which has previously been observed to shield the active site in the type IV fold homodimer. The active site of MtIlvE contains density corresponding to bound PMP, which is likely to be a consequence of the presence of tryptone in the crystallization medium. Additionally, two cysteine residues are positioned at the dimer interface for disulfide-bond formation under oxidative conditions. It is unknown whether they are involved in any regulatory activities analogous to those of the human mitochondrial branched-chain amino-acid transaminase.

  15. A double amino-acid change in the HLA-A peptide-binding groove is associated with response to psychotropic treatment in patients with schizophrenia

    PubMed Central

    Le Clerc, S; Taing, L; Fond, G; Meary, A; Llorca, P-M; Blanc, O; Beaune, P; Rajagopal, K; Jamain, S; Tamouza, R; Zagury, J-F; Leboyer, M

    2015-01-01

    The choice of an efficient psychotropic treatment for patients with schizophrenia is a key issue to improve prognosis and quality of life and to decrease the related burden and costs. As for other complex disorders, response to drugs in schizophrenia is highly heterogeneous and the underlying molecular mechanisms of this diversity are still poorly understood. In a carefully followed-up cohort of schizophrenic patients prospectively treated with risperidone or olanzapine, we used a specially designed single-nucleotide polymorphism (SNP) array to perform a large-scale genomic analysis and identify genetic variants associated with response to psychotropic drugs. We found significant associations between response to treatment defined by the reduction in psychotic symptomatology 42 days after the beginning of treatment and SNPs located in the chromosome 6, which houses the human leukocyte antigen (HLA). After imputation of the conventional HLA class I and class II alleles, as well as the amino-acid variants, we observed a striking association between a better response to treatment and a double amino-acid variant at positions 62 and 66 of the peptide-binding groove of the HLA-A molecule. These results support the current notion that schizophrenia may have immune-inflammatory underpinnings and may contribute to pave the way for personalized treatments in schizophrenia. PMID:26218850

  16. The complete amino-acid sequence of the alpha and beta subunits of B-phycoerythrin from the rhodophytan alga Porphyridium cruentum.

    PubMed

    Sidler, W; Kumpf, B; Suter, F; Klotz, A V; Glazer, A N; Zuber, H

    1989-02-01

    Determination of the complete amino-acid sequence of the subunits of B-phycoerythrin from Porphyridium cruentum has shown that the alpha subunit contains 164 amino-acid residues and the beta subunit contains 177 residues. When the sequences of B- and C-phycoerythrins are aligned with those of other phycobiliproteins, it is obvious that B-phycoerythrin lacks a deletion at beta-21-22 present in C-phycoerythrin. However, relative to C-phycoerythrin from Fremyella diplosiphon (Calothrix) (Sidler, W., Kumpf, B., Rüdiger, W. and Zuber, H. (1986) Biol. Chem. Hoppe-Seyler 367, 627-642), B-phycoerythrin has deletions at beta-141k-o, beta-142, beta-143, beta-147 and beta-148. The four singly-linked phycoerythrobilins at positions alpha-84, alpha-143a, beta-84 and beta-155, and the doubly-linked phycoerythrobilin at position beta-50/61 are at sites homologous to the attachment sites in C-phycoerythrin. The aspartyl residues (alpha-87, beta-87, and beta-39), that interact with the bilins at alpha-84, beta-84, and beta-155 in C-phycocyanin, are found in the homologous positions in B-phycoerythrin. B-Phycoerythrin, in common with other phycobiliproteins, contains a N gamma-methylasparagine residue at position beta-72.

  17. Apoptotic Killing of Breast Cancer Cells by IgYs Produced Against a Small 21 Aminoacid Epitope of the Human TRAIL-2 Receptor.

    PubMed

    Amirijavid1, Shaghayegh; Entezari, Maliheh; Movafagh, Abolfazl; Hashemi, Mehrdad; Mosavi-Jarahi, Alireza; Dehghani, Hossein

    2016-01-01

    TRAIL, tumor necrosis factor (TNF)-related apoptosis-inducing ligand belongs to one of important cytokine superfamilIES, tumor necrosis factor (TNFα) . TRAIL-2 receptor agonists activate several cell signaling pathways in cells in different manners and could lead to apoptosis or necrosis. Agonistic egg yolk antibodies like IgY which have been developed in a selective manner could activate TRAIL death receptors such as TRAIL-2 (DR5) and thus apoptosis signaling. We here investigated induction of apoptosis in human breast cancer cells (MCF7 cell line) by an IgY produced against an 21 aminoacid epitope of the human TRAIL-2 receptor. As the first step a small peptide of 21 aminoacids choosen from the extracellular domain of DR5 protein was produced with a peptide synthesizer. After control assays and confirmation of the correct amino acid sequence, it was injected to hens immunized to achieve high affinity IgYs. At the next step, the produced IgYs were extracted and examined for specificity against DR5 protein by ELISA assay. Subsequently, the anticancer effect of such IgYs was determined by MTT assay in the MCF7 human breast cancer cell line. The produced peptides successfully immunized hens and the produced antibodies which accumulated in egg yolk specifically recognized the DR5 protein. IgYs exerted significant toxicity and killed MCF7 cells as shown by MTT assay. PMID:27165241

  18. Economic aspects of drug substitution

    PubMed Central

    Salehi, Hossein; Schweitzer, Stuart O.

    1985-01-01

    One of the major directions of health policy is the attempt to contain expenditures on pharmaceuticals by encouraging substitution of generic for brand name drug products. Yet, a major marketing survey of prescribing and dispensing patterns in California in 1977 found relatively little drug substitution occurring, and in fact substitution of more expensive products occurred more frequently than did substitution of less expensive products. This article tests alternative models of pharmacy dispensing behavior to better explain substitution patterns and it estimates price functions to measure the extent to which cost savings on generic products are passed on to consumers. PMID:10311162

  19. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ....-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic). 721.10214 Section 721.10214... Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic... identified generically as poly(oxyalkylenediyl),.alpha.-substituted...

  20. Explicit Substitutions and All That

    NASA Technical Reports Server (NTRS)

    Ayala-Rincon, Mauricio; Munoz, Cesar; Busnell, Dennis M. (Technical Monitor)

    2000-01-01

    Explicit substitution calculi are extensions of the Lambda-calculus where the substitution mechanism is internalized into the theory. This feature makes them suitable for implementation and theoretical study of logic-based tools such as strongly typed programming languages and proof assistant systems. In this paper we explore new developments on two of the most successful styles of explicit substitution calculi: the lambda(sigma)- and lambda(s(e))-calculi.

  1. Explicit Substitutions and All That

    NASA Technical Reports Server (NTRS)

    Ayala-Rincon, Mauricio; Munoz, Cesar

    2000-01-01

    Explicit substitution calculi are extensions of the lambda-calculus where the substitution mechanism is internalized into the theory. This feature makes them suitable for implementation and theoretical study of logic-based tools such as strongly typed programming languages and proof assistant systems. In this paper we explore new developments on two of the most successful styles of explicit substitution calculi: the lambda sigma- and lambda S(e)-calculi.

  2. Nanoflakes of an aminoacid-based chiral coordination polymer: Synthesis, optical and electrochemical properties, and application in electrochemical sensing of H2O2

    NASA Astrophysics Data System (ADS)

    Zhou, Bo; Liang, Li-Mei; Yao, Jie

    2015-03-01

    Nanoflakes of an aminoacid-based chiral coordination polymer (CP), [Cu2(tyr)2(bipy)]n, were synthesized successfully in the presence of surfactant, as evidenced by the XRD and SEM results. UV-vis absorption spectrometry and fluorescence spectrometry were used to investigate the optical properties of the CP, which was found to be mainly attributed to the ligands, while the forming of the CP caused only slight change. On the other hand, Cu(II) ions acted as electrocatalytic active sites of the CP, as evidenced by cyclic voltammetry. The CP also showed good performance in the electrochemical sensing of H2O2: sensitivity of 85.6 mA mol-1 L cm-2, linear range of 1.0×10-5-7.69×10-3 M, detection limit of 1.0×10-5 M (S/N=3), and fast response in mere 5 s.

  3. Practical use of chemical shift databases for protein solid-state NMR: 2D chemical shift maps and amino-acid assignment with secondary-structure information.

    PubMed

    Fritzsching, K J; Yang, Y; Schmidt-Rohr, K; Hong, Mei

    2013-06-01

    We introduce a Python-based program that utilizes the large database of (13)C and (15)N chemical shifts in the Biological Magnetic Resonance Bank to rapidly predict the amino acid type and secondary structure from correlated chemical shifts. The program, called PACSYlite Unified Query (PLUQ), is designed to help assign peaks obtained from 2D (13)C-(13)C, (15)N-(13)C, or 3D (15)N-(13)C-(13)C magic-angle-spinning correlation spectra. We show secondary-structure specific 2D (13)C-(13)C correlation maps of all twenty amino acids, constructed from a chemical shift database of 262,209 residues. The maps reveal interesting conformation-dependent chemical shift distributions and facilitate searching of correlation peaks during amino-acid type assignment. Based on these correlations, PLUQ outputs the most likely amino acid types and the associated secondary structures from inputs of experimental chemical shifts. We test the assignment accuracy using four high-quality protein structures. Based on only the Cα and Cβ chemical shifts, the highest-ranked PLUQ assignments were 40-60 % correct in both the amino-acid type and the secondary structure. For three input chemical shifts (CO-Cα-Cβ or N-Cα-Cβ), the first-ranked assignments were correct for 60 % of the residues, while within the top three predictions, the correct assignments were found for 80 % of the residues. PLUQ and the chemical shift maps are expected to be useful at the first stage of sequential assignment, for combination with automated sequential assignment programs, and for highly disordered proteins for which secondary structure analysis is the main goal of structure determination.

  4. Mutational analysis of Raf-1 cysteine rich domain: requirement for a cluster of basic aminoacids for interaction with phosphatidylserine.

    PubMed

    Improta-Brears, T; Ghosh, S; Bell, R M

    1999-08-01

    Activation of Raf-1 kinase is preceded by a translocation of Raf-1 to the plasma membrane in response to external stimuli. The membrane localization of Raf-1 is facilitated through its interaction with activated Ras and with membrane phospholipids. Previous evidence suggests that the interaction of Raf-1 with Ras is mediated by two distinct domains within the N-terminal region of Raf-1 comprising amino acid residues 51-131 and residues 139-184, the latter of which codes for a zinc containing cysteine-rich domain. The cysteine-rich domain of Raf-1 is also reported to associate with other proteins, such as 14-3-3, and for selectively binding acidic phospholipids, particularly phosphatidylserine (PS). In the present study, we have investigated the consequences of progressive deletions and point mutations within the cysteine-rich domain of Raf-1 on its ability to bind PS. A reduced interaction with PS was observed in vitro for all deletion mutants of Raf-1 expressed either as full-length proteins or as fragments containing the isolated cysteine-rich domain. In particular, the cluster of basic amino acids R143, K144, and K148 appeared to be critical for interaction with PS, since substitution of all three residues to alanine resulted in a protein that failed to interact with liposomes enriched for PS. Expression of Raf-1 in vivo, containing point mutations in the cysteine-rich domain resulted in a truncated polypeptide that lacked both the Ras and PS binding sites and could no longer translocate to the plasma membrane upon serum stimulation. These results indicate that the basic residues 143, 144 and 148 in the anterior half of Raf-1 cysteine-rich domain play a role in the association with the lipid bilayer and possibly in protein stability, therefore they might contribute to Raf-1 localization and subsequent activation.

  5. Protein sequences classification by means of feature extraction with substitution matrices

    PubMed Central

    2010-01-01

    Background This paper deals with the preprocessing of protein sequences for supervised classification. Motif extraction is one way to address that task. It has been largely used to encode biological sequences into feature vectors to enable using well-known machine-learning classifiers which require this format. However, designing a suitable feature space, for a set of proteins, is not a trivial task. For this purpose, we propose a novel encoding method that uses amino-acid substitution matrices to define similarity between motifs during the extraction step. Results In order to demonstrate the efficiency of such approach, we compare several encoding methods using some machine learning classifiers. The experimental results showed that our encoding method outperforms other ones in terms of classification accuracy and number of generated attributes. We also compared the classifiers in term of accuracy. Results indicated that SVM generally outperforms the other classifiers with any encoding method. We showed that SVM, coupled with our encoding method, can be an efficient protein classification system. In addition, we studied the effect of the substitution matrices variation on the quality of our method and hence on the classification quality. We noticed that our method enables good classification accuracies with all the substitution matrices and that the variances of the obtained accuracies using various substitution matrices are slight. However, the number of generated features varies from a substitution matrix to another. Furthermore, the use of already published datasets allowed us to carry out a comparison with several related works. Conclusions The outcomes of our comparative experiments confirm the efficiency of our encoding method to represent protein sequences in classification tasks. PMID:20377887

  6. Displacement, Substitution, Sublimation: A Bibliography.

    ERIC Educational Resources Information Center

    Pedrini, D. T.; Pedrini, Bonnie C.

    Sigmund Freund worked with the mechanisms of displacement, substitution, and sublimation. These mechanisms have many similarities and have been studied diagnostically and therapeutically. Displacement and substitution seem to fit in well with phobias, hysterias, somatiyations, prejudices, and scapegoating. Phobias, prejudices, and scapegoating…

  7. A novel skew analysis reveals substitution asymmetries linked to genetic code GC-biases and PolIII a-subunit isoforms

    PubMed Central

    Apostolou-Karampelis, Konstantinos; Nikolaou, Christoforos; Almirantis, Yannis

    2016-01-01

    Strand biases reflect deviations from a null expectation of DNA evolution that assumes strand-symmetric substitution rates. Here, we present strong evidence that nearest-neighbour preferences are a strand-biased feature of bacterial genomes, indicating neighbour-dependent substitution asymmetries. To detect such asymmetries we introduce an alignment free index (relative abundance skews). The profiles of relative abundance skews along coding sequences can trace the phylogenetic relations of bacteria, suggesting that the patterns of neighbour-dependent substitution strand-biases are not common among different lineages, but are rather species-specific. Analysis of neighbour-dependent and codon-site skews sheds light on the origins of substitution asymmetries. Via a simple model we argue that the structure of the genetic code imposes position-dependent substitution strand-biases along coding sequences, as a response to GC mutation pressure. Thus, the organization of the genetic code per se can lead to an uneven distribution of nucleotides among different codon sites, even when requirements for specific codons and amino-acids are not accounted for. Moreover, our results suggest that strand-biases in replication fidelity of PolIII α-subunit induce substitution asymmetries, both neighbour-dependent and independent, on a genome scale. The role of DNA repair systems, such as transcription-coupled repair, is also considered. PMID:27345720

  8. How Do Substitute Teachers Substitute? An Empirical Study of Substitute-Teacher Labor Supply

    ERIC Educational Resources Information Center

    Gershenson, Seth

    2012-01-01

    This paper examines the daily labor supply of a potentially important, but often overlooked, source of instruction in U.S. public schools: substitute teachers. I estimate a sequential binary-choice model of substitute teachers' job-offer acceptance decisions using data on job offers made by a randomized automated calling system. Importantly, this…

  9. The Replacement of 10 Non-Conserved Residues in the Core Protein of JFH-1 Hepatitis C Virus Improves Its Assembly and Secretion

    PubMed Central

    Etienne, Loïc; Blanchard, Emmanuelle; Boyer, Audrey; Desvignes, Virginie; Gaillard, Julien; Meunier, Jean-Christophe; Roingeard, Philippe; Hourioux, Christophe

    2015-01-01

    Hepatitis C virus (HCV) assembly is still poorly understood. It is thought that trafficking of the HCV core protein to the lipid droplet (LD) surface is essential for its multimerization and association with newly synthesized HCV RNA to form the viral nucleocapsid. We carried out a mapping analysis of several complete HCV genomes of all genotypes, and found that the genotype 2 JFH-1 core protein contained 10 residues different from those of other genotypes. The replacement of these 10 residues of the JFH-1 strain sequence with the most conserved residues deduced from sequence alignments greatly increased virus production. Confocal microscopy of the modified JFH-1 strain in cell culture showed that the mutated JFH-1 core protein, C10M, was present mostly at the endoplasmic reticulum (ER) membrane, but not at the surface of the LDs, even though its trafficking to these organelles was possible. The non-structural 5A protein of HCV was also redirected to ER membranes and colocalized with the C10M core protein. Using a Semliki forest virus vector to overproduce core protein, we demonstrated that the C10M core protein was able to form HCV-like particles, unlike the native JFH-1 core protein. Thus, the substitution of a few selected residues in the JFH-1 core protein modified the subcellular distribution and assembly properties of the protein. These findings suggest that the early steps of HCV assembly occur at the ER membrane rather than at the LD surface. The C10M-JFH-1 strain will be a valuable tool for further studies of HCV morphogenesis. PMID:26339783

  10. Vitreous substitutes: challenges and directions

    PubMed Central

    Gao, Qian-Ying; Fu, Yue; Hui, Yan-Nian

    2015-01-01

    The natural vitreous body has a fine structure and complex functions. The imitation of the natural vitreous body by vitreous substitutes is a challenging work for both researchers and ophthalmologists. Gases, silicone oil, heavy silicone oil and hydrogels, particularly the former two vitreous substitutes are clinically widely used with certain complications. Those, however, are not real artificial vitreous due to lack of structure and function like the natural vitreous body. This article reviews the situations, challenges, and future directions in the development of vitreous substitutes, particularly the experimental and clinical use of a new artificial foldable capsular vitreous body. PMID:26085987

  11. Substitution Rates under Stabilizing Selection

    PubMed Central

    Hastings, Alan

    1987-01-01

    Allelic substitutions under stabilizing phenotypic selection on quantitative traits are studied in Monte Carlo simulations of 8 and 16 loci. The results are compared and contrasted to analytical models based on work of M. Kimura for two and "infinite" loci. Selection strengths of S = 4Nes approximately four (which correspond to reasonable strengths of selection for quantitative characters) can retard substitution rates tenfold relative to rates under neutrality. An important finding is a strong dependence of per locus substitution rates on the number of loci. PMID:3609727

  12. Factor substitution in nursing homes.

    PubMed

    Cawley, John; Grabowski, David C; Hirth, Richard A

    2006-03-01

    This paper studies factor substitution in one important sector: the nursing home industry. Specifically, we measure the extent to which nursing homes substitute materials for labor when labor becomes relatively more expensive. From a policy perspective, factor substitution in this market is important because materials-intensive methods of care are associated with greater risks of morbidity and mortality among nursing home residents. Studying longitudinal data from 1991 to 2000 on nearly every nursing home in the United States, we use the method of instrumental variables (IV) to address measurement error in nursing home wages. The results from the IV models yield evidence of factor substitution: higher nursing home wages are associated with greater use of psychoactive drugs and lower quality.

  13. DESIGNING ENVIRONMENTALLY BENIGN SOLVENT SUBSTITUTES

    EPA Science Inventory

    Since the signing of 1987 Montreal Protocol, reducing and eliminating the use of harmful solvents has become an internationally imminent environmental protection mission. Solvent substitution is an effective way to achieve this goal. The Program for Assisting the Replacement of...

  14. Nucleophilic Substitution by Benzodithioate Anions.

    ERIC Educational Resources Information Center

    Bonnans-Plaisance, Chantal; Gressier, Jean-Claude

    1988-01-01

    Describes a two-session experiment designed to provide a good illustration of, and to improve student knowledge of, the Grignard reaction and nucleophilic substitution. Discusses the procedure, experimental considerations, and conclusion of this experiment. (CW)

  15. Blood substitutes based on nanobiotechnology.

    PubMed

    Chang, Thomas Ming Swi

    2006-08-01

    Stimulated by concerns of potential infective agents in donated blood, commercial enterprises have attempted to develop blood substitutes since the 1900s. After several years of development, a few of the many leads are showing promise. In this article, nanobiotechnological approaches that are now in phase III clinical trials are reviewed, followed by a discussion of how important basic knowledge gained is being used to develop new generations of blood substitutes based on nanobiotechnology.

  16. Electrophilic Substitution Reactions of Indoles

    NASA Astrophysics Data System (ADS)

    Sundberg, Richard J.

    The topic of this chapter is electrophilic substitution of indole and its derivatives. The indole ring is highly reactive at its 3-position toward protonation, halogenation, alkylation and acylation. Electrophilic substitution can be combined with inter- or intramolecular addition at C-2. Intramolecular alkylation by iminium ions (Pictet-Spengler reaction) is particularly useful. Enantioselectivity can be achieved in many conjugate addition reactions. These reactions have been applied to synthesis of both natural products and drugs.

  17. Nonallograft osteoconductive bone graft substitutes.

    PubMed

    Bucholz, Robert W

    2002-02-01

    An estimated 500,000 to 600,000 bone grafting procedures are done annually in the United States. Approximately (1/2) of these surgeries involve spinal arthrodesis whereas 35% to 40% are used for general orthopaedic applications. Synthetic bone graft substitutes currently represent only 10% of the bone graft market, but their share is increasing as experience and confidence in their use are accrued. Despite 15 to 20 years of clinical experience with various synthetic substitutes, there have been few welldesigned, controlled clinical trials of these implants. Synthetic bone graft substitutes consist of hydroxyapatite, tricalcium phosphate, calcium sulfate, or a combination of these minerals. Their fabrication technique, crystallinity, pore dimensions, mechanical properties, and resorption rate vary. All synthetic porous substitutes share numerous advantages over autografts and allografts including their unlimited supply, easy sterilization, and storage. However, the degree to which the substitute provides an osteoconductive structural framework or matrix for new bone ingrowth differs among implants. Disadvantages of ceramic implants include brittle handling properties, variable rates of resorption, poor performance in diaphyseal defects, and potentially adverse effects on normal bone remodeling. These inherent weaknesses have refocused their primary use to bone graft extenders and carriers for pharmaceuticals. The composition, histologic features, indications, and clinical experience of several of the synthetic bone graft substitutes approved for orthopaedic use in the United States are reviewed. PMID:11937865

  18. Exploring the structure of the 100 amino-acid residue long N-terminus of the plant antenna protein CP29.

    PubMed

    Shabestari, Maryam Hashemi; Wolfs, Cor J A M; Spruijt, Ruud B; van Amerongen, Herbert; Huber, Martina

    2014-03-18

    The structure of the unusually long (∼100 amino-acid residues) N-terminal domain of the light-harvesting protein CP29 of plants is not defined in the crystal structure of this membrane protein. We studied the N-terminus using two electron paramagnetic resonance (EPR) approaches: the rotational diffusion of spin labels at 55 residues with continuous-wave EPR, and three sets of distances with a pulsed EPR method. The N-terminus is relatively structured. Five regions that differ considerably in their dynamics are identified. Two regions have low rotational diffusion, one of which shows α-helical character suggesting contact with the protein surface. This immobile part is flanked by two highly dynamic, unstructured regions (loops) that cover residues 10-22 and 82-91. These loops may be important for the interaction with other light-harvesting proteins. The region around residue 4 also has low rotational diffusion, presumably because it attaches noncovalently to the protein. This section is close to a phosphorylation site (Thr-6) in related proteins, such as those encoded by the Lhcb4.2 gene. Phosphorylation might influence the interaction with other antenna complexes, thereby regulating the supramolecular organization in the thylakoid membrane.

  19. Elimination of infused branched-chain amino-acids from plasma of patients with non-obese type 2 diabetes mellitus.

    PubMed

    Marchesini, G; Bianchi, G P; Vilstrup, H; Capelli, M; Zoli, M; Pisi, E

    1991-04-01

    Increased plasma levels of branched-chain amino-acids (BCAA) have been demonstrated in poorly controlled diabetes mellitus, and related to absolute or relative insulin deficiency. To study the pathogenesis of this alteration, the elimination of BCAA from plasma was measured in 8 patients with non-obese type 2 diabetes mellitus and in 8 age-matched control subjects during steady-state BCAA concentrations induced by a primed-continuous infusion. Fasting BCAA levels were increased by 40-50% in patients with diabetes. The plasma clearances of valine, isoleucine, and leucine, calculated as infusion rate divided by steady-state concentration, were reduced by 20% in diabetics, despite 50% hyperinsulinemia (P < 0.01). Basal BCAA levels and BCAA clearance were negatively correlated (r(2) = 0.46 - 0.56). The endogenous basal appearance rates of BCAA, estimated by the basal concentrations multiplied by the plasma clearances, were normal in diabetics, and there was no difference in the apparent volumes of distribution of BCAA. The increased basal concentration of BCAA in poorly controlled type 2 diabetics (693 [SD 114; n = 8] mumol/l vs 479 [88; n = 8] in controls (P < 0.005) is attributable to changes in plasma clearances, without any change in the efflux of BCAA into plasma. This may be due to insulin resistance.

  20. Substitutes for leadership: test of a construct.

    PubMed

    Howell, J P; Dorfman, P W

    1981-12-01

    The study reported here examined the impact of leadership substitutes on subordinate job satisfaction and organizational commitment. Leadership substitutes, as suggested by Kerr (1977), replace or "act in the place of" a specific leader behavior. Multiple regression was used to test the validity and strength of potential substitutes. Results indicated mixed support for the substitutes construct. PMID:10253689

  1. Point substitutions in Japanese alloalbumins.

    PubMed

    Arai, K; Madison, J; Huss, K; Ishioka, N; Satoh, C; Fujita, M; Neel, J V; Sakurabayashi, I; Putnam, F W

    1989-08-01

    We have completed the structural study of five rare types of inherited albumin variants (alloalbumins) discovered in the Biochemical Genetics Study of 15,581 unrelated children in Hiroshima and Nagasaki. We have also identified the structural change in five other alloalbumin specimens detected during clinical electrophoresis of sera from Japanese living near Tokyo. Each of the five albumin variants from Nagasaki and Hiroshima has a single amino acid substitution. All of these substitutions differ, and none has been reported in non-Japanese populations. No instances of proalbumin variants or of albumin B (the most frequent alloalbumins in Caucasians) were detected in the children in Hiroshima and Nagasaki. However, one instance of a variant proalbumin and two examples of albumin B occurred in Japanese from the vicinity of Tokyo. In addition a previously unreported point substitution was found in albumin Tochigi, which is present in two unrelated persons from Tochigi prefecture. Four of the point mutations in the Japanese alloalbumins are in close proximity in a short segment of the polypeptide chain (residues 354-382) in which three additional point substitutions have been reported in diverse populations. These results, combined with earlier data, suggest that point substitutions are grouped in certain segments of the albumin molecule.

  2. Unified optical symbolic substitution processor

    NASA Astrophysics Data System (ADS)

    Casasent, David P.

    1990-07-01

    Symbolic substitution operations can be realized optically on a correlator. This is a very attractive and efficient architecture for symbolic substitution. It allows parallel multichannel realization with a fixed set of filters (on film or easily realized on low space bandwidth product spatial light modulators) using space and frequency-multiplexing or sequential filters. All basic logic, numeric and morphological image processing functions can be achieved by symbolic substitution. Moreover, all operations are possible on one multifunctional optical processor. Morphological operations are felt to be essential for ATR and pattern recognition preprocessing in clutter. They greatly improve the role for optics by allowing the same optical architecture to be used for low, medium and high level vision.

  3. Substitution systems and nonextensive statistics

    NASA Astrophysics Data System (ADS)

    García-Morales, V.

    2015-12-01

    Substitution systems evolve in time by generating sequences of symbols from a finite alphabet: At a certain iteration step, the existing symbols are systematically replaced by blocks of Nk symbols also within the alphabet (with Nk, a natural number, being the length of the kth block of the substitution). The dynamics of these systems leads naturally to fractals and self-similarity. By using B-calculus (García-Morales, 2012) universal maps for deterministic substitution systems both of constant and non-constant length, are formulated in 1D. It is then shown how these systems can be put in direct correspondence with Tsallis entropy. A 'Second Law of Thermodynamics' is also proved for these systems in the asymptotic limit of large words.

  4. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  5. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted...

  6. Insights into the influence of 5-HT2c aminoacidic variants with the inhibitory action of serotonin inverse agonists and antagonists.

    PubMed

    Galeazzi, Roberta; Massaccesi, Luca; Piva, Francesco; Principato, Giovanni; Laudadio, Emilioano

    2014-03-01

    Specific modulation of serotonin 5-HT(2C) G protein-coupled receptors may be therapeutic for obesity and neuropsychiatric disorders. The different efficacy of drugs targeting these receptors are due to the presence of genetic variants in population and this variability is still hard to predict. Therefore, in order to administer the more suitable drug, taking into account patient genotype, it is necessary to know the molecular effects of its gene nucleotide variations. In this work, starting from an accurate 3D model of 5-HT(2C), we focus on the prediction of the possible effect of some single nucleotide polymorphisms (SNPs) producing amino acidic changes in proximity of the 5-HT(2C) ligand binding site. Particularly we chose a set of 5-HT(2C) inverse agonists and antagonists which have high inhibitory activity. After prediction of the structures of the receptor-ligand complexes using molecular docking tools, we performed full atom molecular dynamics simulations in explicit lipid bilayer monitoring the interactions between ligands and trans-membrane helices of the receptor, trying to infer relations with their biological activity. Serotonin, as the natural ligand was chosen as reference compound to advance a hypothesis able to explain the receptor inhibition mechanism. Indeed we observed a different behavior between the antagonists and inverse agonist with respect to serotonin or unbounded receptor, which could be responsible, even if not directly, of receptor's inactivation. Furthermore, we analyzed five aminoacidic variants of 5HT(2C) receptor observing alterations in the interactions between ligands and receptor which give rise to changes of free energy values for every complex considered.

  7. A high load of non-neutral amino-acid polymorphisms explains high protein diversity despite moderate effective population size in a marine bivalve with sweepstakes reproduction.

    PubMed

    Harrang, Estelle; Lapègue, Sylvie; Morga, Benjamin; Bierne, Nicolas

    2013-02-01

    Marine bivalves show among the greatest allozyme diversity ever reported in Eukaryotes, putting them historically at the heart of the neutralist-selectionist controversy on the maintenance of genetic variation. Although it is now acknowledged that this high diversity is most probably a simple consequence of a large population size, convincing support for this explanation would require a rigorous assessment of the silent nucleotide diversity in natural populations of marine bivalves, which has not yet been done. This study investigated DNA sequence polymorphism in a set of 37 nuclear loci in wild samples of the flat oyster Ostrea edulis. Silent diversity was found to be only moderate (0.7%), and there was no departure from demographic equilibrium under the Wright-Fisher model, suggesting that the effective population size might not be as large as might have been expected. In accordance with allozyme heterozygosity, nonsynonymous diversity was comparatively very high (0.3%), so that the nonsynonymous to silent diversity ratio reached a value rarely observed in any other organism. We estimated that one-quarter of amino acid-changing mutations behave as neutral in O. edulis, and as many as one-third are sufficiently weakly selected to segregate at low frequency in the polymorphism. Finally, we inferred that one oyster is expected to carry more than 4800 non-neutral alleles (or 4.2 cM(-1)). We conclude that a high load of segregating non-neutral amino-acid polymorphisms contributes to high protein diversity in O. edulis. The high fecundity of marine bivalves together with an unpredictable and highly variable success of reproduction and recruitment (sweepstakes reproduction) might produce a greater decoupling between Ne and N than in other organisms with lower fecundities, and we suggest this could explain why a higher segregating load could be maintained for a given silent mutation effective size.

  8. A High Load of Non-neutral Amino-Acid Polymorphisms Explains High Protein Diversity Despite Moderate Effective Population Size in a Marine Bivalve With Sweepstakes Reproduction

    PubMed Central

    Harrang, Estelle; Lapègue, Sylvie; Morga, Benjamin; Bierne, Nicolas

    2013-01-01

    Marine bivalves show among the greatest allozyme diversity ever reported in Eukaryotes, putting them historically at the heart of the neutralist−selectionist controversy on the maintenance of genetic variation. Although it is now acknowledged that this high diversity is most probably a simple consequence of a large population size, convincing support for this explanation would require a rigorous assessment of the silent nucleotide diversity in natural populations of marine bivalves, which has not yet been done. This study investigated DNA sequence polymorphism in a set of 37 nuclear loci in wild samples of the flat oyster Ostrea edulis. Silent diversity was found to be only moderate (0.7%), and there was no departure from demographic equilibrium under the Wright-Fisher model, suggesting that the effective population size might not be as large as might have been expected. In accordance with allozyme heterozygosity, nonsynonymous diversity was comparatively very high (0.3%), so that the nonsynonymous to silent diversity ratio reached a value rarely observed in any other organism. We estimated that one-quarter of amino acid-changing mutations behave as neutral in O. edulis, and as many as one-third are sufficiently weakly selected to segregate at low frequency in the polymorphism. Finally, we inferred that one oyster is expected to carry more than 4800 non-neutral alleles (or 4.2 cM−1). We conclude that a high load of segregating non-neutral amino-acid polymorphisms contributes to high protein diversity in O. edulis. The high fecundity of marine bivalves together with an unpredictable and highly variable success of reproduction and recruitment (sweepstakes reproduction) might produce a greater decoupling between Ne and N than in other organisms with lower fecundities, and we suggest this could explain why a higher segregating load could be maintained for a given silent mutation effective size. PMID:23390609

  9. Substituted decision making: elder guardianship.

    PubMed

    Leatherman, Martha E; Goethe, Katherine E

    2009-11-01

    The goal of this column is to help experienced clinicians navigate the judicial system when they are confronted with requests for capacity evaluations that involve guardianship (conservatorship). The interface between the growing elderly medical population and increasing requests for substituted decision making is becoming more complex. This column will help practicing psychiatrists understand the medical, legal, and societal factors involved in adult guardianship. Such understanding is necessary in order to effectively perform guardianship evaluations and adequately inform courts, patients, and families about the psychiatric diagnoses central to substituted decision making.

  10. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Poly(oxyalkylenediyl),.alpha... Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic... identified generically as poly(oxyalkylenediyl),.alpha.-substituted...

  11. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxyalkylenediyl),.alpha... Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic... identified generically as poly(oxyalkylenediyl),.alpha.-substituted...

  12. 40 CFR 721.10214 - Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Poly(oxyalkylenediyl),.alpha... Poly(oxyalkylenediyl),.alpha.-substituted carbomonocycle-.omega.-substituted carbomonocycle (generic... identified generically as poly(oxyalkylenediyl),.alpha.-substituted...

  13. 'Vegetable' substitutes for diesel fuel

    SciTech Connect

    Not Available

    1981-07-22

    Research programs in the US, Brazil, South Africa and the Philippines on efforts to find a vegetable oil substitute for diesel fuel are reported. A narrowing price gap with diesel fuel and a favourable energy balance improve the prospects for such fuels. Much of the current work is centered on blends, rather than the use of the pure oil.

  14. No Substitute Teacher Left behind

    ERIC Educational Resources Information Center

    O'Connor, Kevin

    2009-01-01

    Schools and districts routinely recruit, retain, and support highly qualified teachers to ensure that students receive the best learning opportunities. However, even if one's school employs highly qualified full-time teachers, it is important to acknowledge that substitute teachers also have a significant impact on the education of students. One…

  15. Substitute Teaching: Sink or Swim.

    ERIC Educational Resources Information Center

    Duebber, Diane

    2000-01-01

    Advises new substitute teachers to be prepared, tote emergency activity folders, dress professionally (but wear flamingo earrings), be early, figure out the game plan, communicate expectations to students, enforce consequences, have a gimmick to reward cooperation, relish the teachable moment, leave the room tidy, and believe in themselves. (MLH)

  16. Estimating the Variability of Substitution Rates

    PubMed Central

    Bulmer, M.

    1989-01-01

    Suppose that amino acid or nucleotide data are available for a homologous gene in several species which diverged from a common ancestor at about the same time and that substitution rates between all pairs of species are calculated, correcting as necessary for multiple substitutions and for back and parallel substitutions. The variances and covariances of these corrected substitution rates are evaluated, and are used to construct a new test for uniformity (constancy of the molecular clock) and to find the best estimates of substitution rates in individual lineages with their standard errors. A substantial bias may arise if the effect of correcting the pairwise substitution rates is ignored. PMID:2599371

  17. Effect of ageing and ischemia on enzymatic activities linked to Krebs' cycle, electron transfer chain, glutamate and aminoacids metabolism of free and intrasynaptic mitochondria of cerebral cortex.

    PubMed

    Villa, Roberto Federico; Gorini, Antonella; Hoyer, Siegfried

    2009-12-01

    The effect of ageing and the relationships between the catalytic properties of enzymes linked to Krebs' cycle, electron transfer chain, glutamate and aminoacid metabolism of cerebral cortex, a functional area very sensitive to both age and ischemia, were studied on mitochondria of adult and aged rats, after complete ischemia of 15 minutes duration. The maximum rate (Vmax) of the following enzyme activities: citrate synthase, malate dehydrogenase, succinate dehydrogenase for Krebs' cycle; NADH-cytochrome c reductase as total (integrated activity of Complex I-III), rotenone sensitive (Complex I) and cytochrome oxidase (Complex IV) for electron transfer chain; glutamate dehydrogenase, glutamate-oxaloacetate-and glutamate-pyruvate transaminases for glutamate metabolism were assayed in non-synaptic, perikaryal mitochondria and in two populations of intra-synaptic mitochondria, i.e., the light and heavy mitochondrial fraction. The results indicate that in normal, steady-state cerebral cortex, the value of the same enzyme activity markedly differs according (a) to the different populations of mitochondria, i.e., non-synaptic or intra-synaptic light and heavy, (b) and respect to ageing. After 15 min of complete ischemia, the enzyme activities of mitochondria located near the nucleus (perikaryal mitochondria) and in synaptic structures (intra-synaptic mitochondria) of the cerebral tissue were substantially modified by ischemia. Non-synaptic mitochondria seem to be more affected by ischemia in adult and particularly in aged animals than the intra-synaptic light and heavy mitochondria. The observed modifications in enzyme activities reflect the metabolic state of the tissue at each specific experimental condition, as shown by comparative evaluation with respect to the content of energy-linked metabolites and substrates. The derangements in enzyme activities due to ischemia is greater in aged than in adult animals and especially the non-synaptic and the intra-synaptic light

  18. Interrelationships among biological activity, disulfide bonds, secondary structure, and metal ion binding for a chemically synthesized 34-amino-acid peptide derived from alpha-fetoprotein.

    PubMed

    MacColl, R; Eisele, L E; Stack, R F; Hauer, C; Vakharia, D D; Benno, A; Kelly, W C; Mizejewski, G J

    2001-10-01

    A 34-amino-acid peptide has been chemically synthesized based on a sequence from human alpha-fetoprotein. The purified peptide is active in anti-growth assays when freshly prepared in pH 7.4 buffer at 0.20 g/l, but this peptide slowly becomes inactive. This functional change is proven by mass spectrometry to be triggered by the formation of an intrapeptide disulfide bond between the two cysteine residues on the peptide. Interpeptide cross-linking does not occur. The active and inactive forms of the peptide have almost identical secondary structures as shown by circular dichroism (CD). Zinc ions bind to the active peptide and completely prevents formation of the inactive form. Cobalt(II) ions also bind to the peptide, and the UV-Vis absorption spectrum of the cobalt-peptide complex shows that: (1) a near-UV sulfur-to-metal-ion charge-transfer band had a molar extinction coefficient consistent with two thiolate bonds to Co(II); (2) the lowest-energy visible d-d transition maximum at 659 nm, also, demonstrated that the two cysteine residues are ligands for the metal ion; (3) the d-d molar extinction coefficient showed that the metal ion-ligand complex was in a distorted tetrahedral symmetry. The peptide has two cysteines, and it is speculated that the other two metal ion ligands might be the two histidines. The Zn(II)- and Co(II)-peptide complexes had similar peptide conformations as indicated by their ultraviolet CD spectra, which differed very slightly from that of the free peptide. Surprisingly, the cobalt ions acted in the reverse of the zinc ions in that, instead of stabilizing anti-growth form of the peptide, they catalyzed its loss. Metal ion control of peptide function is a saliently interesting concept. Calcium ions, in the conditions studied, apparently do not bind to the peptide. Trifluoroethanol and temperature (60 degrees C) affected the secondary structure of the peptide, and the peptide was found capable of assuming various conformations in solution

  19. Resonant photodissociation in substituted benzenes

    NASA Astrophysics Data System (ADS)

    Scarborough, Tim; McAcy, Collin; Foote, David; Uiterwaal, Cornelis

    2011-05-01

    Cyclic aromatic molecules are abundant in organic chemistry, with a wide variety of applications, including pharmacology, pollution studies and genetic research. Among the simplest of these molecules is benzene (C6H6) , with many relevant molecules being benzene-like with a single atomic substitution. In such a substitution, the substituent determines a characteristic perturbation of the electronic structure of the molecule. We discuss the substitution of halogens into the ring (C6H5X), and its effects on the dynamics of ionization and dissociation of the molecule without the focal volume effect. In particular, using 800-nm, 50-fs laser pulses, we present results in the dissociation of fluorobenzene, chlorobenzene, bromobenzene and iodobenzene into the phenyl ring (C6H5) and the atomic halogen, and the subsequent ionization of these fragments. The impact of the ``heavy atom effect'' on a 1 (π , π*) -->3 (n , σ*) singlet-triplet intersystem crossing will be emphasized. Currently under investigation is whether such a dissociation can be treated as an effective source of the neutral substituent. This material is based upon work supported by the National Science Foundation under Grant No. PHY-0355235.

  20. Ethynyl and substituted ethynyl-terminated polysulfones

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M. (Inventor)

    1984-01-01

    Ethynyl and substituted ethynyl-terminated polysulfones and a process for preparing the same are disclosed. These polysulfones are thermally cured to induce cross-linking and chain extension, producing a polymer system with improved solvent resistance and use temperature. Also disclosed are substituted 4-ethynylbenzoyl chlorides as precursors to the substituted ethynyl-terminated polysulfones and a process for preparing the same.

  1. Ethynyl and substituted ethynyl-terminated polysulfones

    NASA Technical Reports Server (NTRS)

    Hergenrother, P. M. (Inventor)

    1986-01-01

    Ethynyl and substituted ethynyl-terminated polysulfones and their synthesis are disclosed. These polysulfones are thermally cured to induce cross-linking and chain extension, producing a polymer system with improved solvent resistance and use temperatures. Also disclosed are substituted 4-ethynylbenzoyl chlorides as precursors to the substituted ethynyl-terminated polysulfones and a process for preparing the same.

  2. 40 CFR 721.9100 - Substituted quinoline.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted quinoline. 721.9100... Substances § 721.9100 Substituted quinoline. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted quinoline (PMN P-93-1183)...

  3. 40 CFR 721.9100 - Substituted quinoline.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted quinoline. 721.9100... Substances § 721.9100 Substituted quinoline. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted quinoline (PMN P-93-1183)...

  4. 40 CFR 721.5867 - Substituted phenol.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  5. 40 CFR 721.5867 - Substituted phenol.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  6. 24 CFR 221.252 - Substitute mortgagors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Cost Homes § 221.252 Substitute mortgagors. (a) Selling mortgagor. The mortgagee may effect the release... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 221.252... approval of a substitute mortgagor, as provided by this section. (b) Purchasing mortgagor. The...

  7. 40 CFR 721.5867 - Substituted phenol.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  8. 40 CFR 721.5867 - Substituted phenol.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  9. 40 CFR 721.5867 - Substituted phenol.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phenol. 721.5867 Section... Substances § 721.5867 Substituted phenol. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted phenol (PMNs P-89-1125,...

  10. Substitutes for School Nurses in Illinois

    ERIC Educational Resources Information Center

    Vollinger, Linda Jeno; Bergren, Martha Dewey; Belmonte-Mann, Frances

    2011-01-01

    The purpose of this descriptive study was to explore utilization of nurse substitutes in the school setting in Illinois. The literature described personnel who staff the school health office in the absence of the school nurse and the barriers to obtaining nurse substitutes. There were no empirical studies conducted on school nurse substitutes in…

  11. 40 CFR 721.323 - Substituted acrylamide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted acrylamide. 721.323... Substances § 721.323 Substituted acrylamide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted acrylamide (PMN P-90-1687)...

  12. 40 CFR 721.323 - Substituted acrylamide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted acrylamide. 721.323... Substances § 721.323 Substituted acrylamide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance generically identified as substituted acrylamide (PMN P-90-1687)...

  13. Expectations and Experiences of Substitute Teachers

    ERIC Educational Resources Information Center

    Duggleby, Patricia; Badali, Sal

    2007-01-01

    This article explores the expectations of support for and the experiences of substitute teachers in an urban school division in Saskatchewan. Data were collected in semistructured interviews with seven substitute teachers. The purpose of the study was to explore how substitute teachers frame their professional experiences and construct their roles…

  14. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  15. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  16. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  17. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  18. 40 CFR 721.6920 - Butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Butyl acrylate, polymer with... acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted silane. (a... butyl acrylate, polymer with substituted methyl styrene, methyl methacrylate, and substituted...

  19. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  20. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  1. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  2. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  3. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  4. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  5. 40 CFR 721.1555 - Substituted phenyl azo substituted benzenediazonium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... benzenediazonium salt. 721.1555 Section 721.1555 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1555 Substituted phenyl azo substituted benzenediazonium salt. (a... generically as a substituted phenyl azo substituted benzenediazonium salt (PMN P-92-652) is subject...

  6. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  7. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  8. 40 CFR 721.9545 - Substituted phenyl azo substituted sulfocarbopolycle, sodium salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sulfocarbopolycle, sodium salt. 721.9545 Section 721.9545 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.9545 Substituted phenyl azo substituted sulfocarbopolycle, sodium salt... identified generically as a substituted phenyl azo substituted sulfocarbopolycle, sodium salt (PMN...

  9. The ATF6-Met[67]Val substitution is associated with increased plasma cholesterol levels

    PubMed Central

    Meex, Steven J.R.; Weissglas-Volkov, Daphna; van der Kallen, Carla J.H.; Thuerauf, Donna J.; van Greevenbroek, Marleen M.J.; Schalkwijk, Casper G.; Stehouwer, Coen D.A.; Feskens, Edith J.M.; Heldens, Lonneke; Ayoubi, Torik A.; Hofker, Marten H.; Wouters, Bradly G.; Vlietinck, Robert; Sinsheimer, Janet S.; Taskinen, Marja-Riitta; Kuusisto, Johanna; Laakso, Markku; de Bruin, Tjerk W.A.; Pajukanta, Päivi; Glembotski, Christopher C.

    2009-01-01

    Objective Activating Transcription Factor 6 (ATF6) is a sensor of the endoplasmic reticulum stress response and regulates expression of several key lipogenic genes. We utilized a two-stage design to investigate whether ATF6 polymorphisms are associated with lipids in subjects at increased risk for cardiovascular disease (CVD). Methods and Results In stage 1, 13 tag-SNPs were tested for association in Dutch samples ascertained for Familial Combined Hyperlipidemia (FCHL) or increased risk for CVD (CVR). In stage 2, we further investigated the SNP with the strongest association from stage 1, a Methionine/Valine substitution at amino-acid 67, in Finnish FCHL families and in subjects with CVR from METSIM, a Finnish population-based cohort. The combined analysis of both stages reached region-wide significance (P=9×10−4), but this association was not seen in the entire METSIM cohort. Our functional analysis demonstrated that Valine at position 67 augments ATF6 protein and its targets Grp78 and Grp94 as well as increases luciferase expression through Grp78 promoter. Conclusions A common nonsynonymous variant in ATF6 increases ATF6 protein levels and is associated with cholesterol levels in subjects at increased risk for CVD, but this association was not seen in a population-based cohort. Further replication is needed to confirm this variant's role in lipids. PMID:19667116

  10. What happened to blood substitutes?

    PubMed

    Stowell, C P

    2005-11-01

    Concerns about the safety and adequacy of the blood supply have fostered twenty years of research into the so-called "blood substitutes" among them the oxygen carriers based on modified hemoglobin. Although none of these materials has yet been licensed for use in North America or Europe, the results of research and clinical trials have increased our understanding of oxygen delivery and its regulation. In particular, the examination of the basis for the vasoactivity observed with some of the hemoglobin based oxygen carriers has led to the insight that several colligative properties of hemoglobin solutions, such as their diffusion coefficient for oxygen, viscosity and colloid oncotic pressure, are important determinants of efficacy.

  11. Current status of erythrocyte substitutes.

    PubMed Central

    Biro, G. P.

    1983-01-01

    During the last two decades the search for alternatives to whole blood transfusions has led to promising developments in the field of erythrocyte substitutes. Hemoglobin solutions free of fragments of erythrocyte stroma and fluorocarbon emulsions are not blood-type-specific and appear likely to satisfy some proportion of our blood requirements. Both must be modified before becoming clinically useful. The oxygen affinity of the hemoglobin solution must be reduced and its intravascular persistence improved. Fluorocarbons cannot yet contribute significantly to the oxygen supply unless the patient breathes hyperbaric oxygen. Recent advances are leading to solutions for these problems. PMID:6344974

  12. Use This Test to Spruce Up Your Substitute Teacher Program.

    ERIC Educational Resources Information Center

    Sendor, Elizabeth

    1982-01-01

    Presents and interprets an 18-question test to determine how well a school's substitute teacher program functions. Topics covered include substitute teacher screening and preparation, lists of substitutes, lesson plans, staff and student evaluation of substitutes, substitutes' salaries, legal considerations, and making substitutes feel needed.…

  13. Formation of substituted oxa- and azarhodacyclobutanes.

    PubMed

    Dauth, Alexander; Rigling, Carla; Tsoung, Jennifer; Love, Jennifer A

    2013-12-01

    The preparation of substituted oxa- and azarhodacyclobutanes is reported. After exchange of ethylene with a variety of unsymmetrically and symmetrically substituted alkenes, the corresponding rhodium-olefin complexes were oxidized with H2O2 and PhINTs (Ts=p-toluenesulfonyl) to yield the substituted oxa- and azarhodacyclobutanes, respectively. Oxarhodacyclobutanes could be prepared with excellent selectivity for incorporation of the oxygen atom on the more substituted carbon atom of the alkene. At the same time, azarhodacyclobutanes showed good-to-excellent selectivity for heteroatom incorporation on the less substituted carbon. Furthermore, it was shown that steric modifications of the ancillary ligand have a significant influence on the selectivity of Rh-olefin complex formation as well as formation of the substituted azametallacycles.

  14. Trends in substitution models of molecular evolution

    PubMed Central

    Arenas, Miguel

    2015-01-01

    Substitution models of evolution describe the process of genetic variation through fixed mutations and constitute the basis of the evolutionary analysis at the molecular level. Almost 40 years after the development of first substitution models, highly sophisticated, and data-specific substitution models continue emerging with the aim of better mimicking real evolutionary processes. Here I describe current trends in substitution models of DNA, codon and amino acid sequence evolution, including advantages and pitfalls of the most popular models. The perspective concludes that despite the large number of currently available substitution models, further research is required for more realistic modeling, especially for DNA coding and amino acid data. Additionally, the development of more accurate complex models should be coupled with new implementations and improvements of methods and frameworks for substitution model selection and downstream evolutionary analysis. PMID:26579193

  15. Trends in substitution models of molecular evolution.

    PubMed

    Arenas, Miguel

    2015-01-01

    Substitution models of evolution describe the process of genetic variation through fixed mutations and constitute the basis of the evolutionary analysis at the molecular level. Almost 40 years after the development of first substitution models, highly sophisticated, and data-specific substitution models continue emerging with the aim of better mimicking real evolutionary processes. Here I describe current trends in substitution models of DNA, codon and amino acid sequence evolution, including advantages and pitfalls of the most popular models. The perspective concludes that despite the large number of currently available substitution models, further research is required for more realistic modeling, especially for DNA coding and amino acid data. Additionally, the development of more accurate complex models should be coupled with new implementations and improvements of methods and frameworks for substitution model selection and downstream evolutionary analysis. PMID:26579193

  16. Substituted Pyrrolo[2,3-d]pyrimidines as Cryptosporidium hominis Thymidylate Synthase Inhibitors

    PubMed Central

    Kumar, Vidya P.; Frey, Kathleen M.; Wang, Yiqiang; Jain, Hitesh K.; Gangjee, Aleem; Anderson, Karen S.

    2013-01-01

    Cryptosporidiosis, a gastrointestinal disease caused by a protozoan Cryptosporidium hominis is often fatal in immunocompromised individuals. There is little clinical data to show that the existing treatment by nitazoxanide and paromomycin is effective in immunocompromised individuals1, 2. Thymidylate synthase (TS) and dihydrofolate reductase (DHFR) are essential enzymes in the folate biosynthesis pathway and are well established as drug targets in cancer and malaria. A novel series of classical antifolates, 2-amino-4-oxo-5-substituted pyrrolo[2,3-d]pyrimidines have been evaluated as Cryptosporidium hominis thymidylate synthase (ChTS) inhibitors. Crystal structure in complex with the most potent compound, a 2’-chlorophenyl with a sulfur bridge with a Ki of 8.83 ± 0.67 nM is discussed in terms of several Van de Waals, hydrophobic and hydrogen bond interactions with the protein residues and the substrate analog 5-fluorodeoxyuridine monophosphate. Of these interactions, two interactions with the non-conserved residues (A287 and S290) offer an opportunity to develop ChTS specific inhibitors. Compound 6 serves as a lead compound for analog design and its crystal structure provides clues for the design of ChTS specific inhibitors. PMID:23927969

  17. Dehalogenation of aromatics by nucleophilic aromatic substitution.

    PubMed

    Sadowsky, Daniel; McNeill, Kristopher; Cramer, Christopher J

    2014-09-16

    Nucleophilic aromatic substitution has been implicated as a mechanism for both the biotic and abiotic hydrodehalogenation of aromatics. Two mechanisms for the aqueous dehalogenation of aromatics involving nucleophilic aromatic substitution with hydride as a nucleophile are investigated using a validated density functional and continuum solvation protocol. For chlorinated and brominated aromatics, nucleophilic addition ortho to carbon-halogen bonds via an anionic intermediate is predicted to be the preferred mechanism in the majority of cases, while concerted substitution is predicted to be preferred for most fluorinated aromatics. Nucleophilic aromatic substitution reactions with the hydroxide and hydrosulfide anions as nucleophiles are also investigated and compared.

  18. Design tool for symbolic substitution

    NASA Astrophysics Data System (ADS)

    Parthasarathi, Ranjani; Jhunjhunwala, Ashok

    1996-11-01

    A design tool that aids in designing, evaluating, and comparing various implementations of optical symbolic substitution is presented. A hierarchical, modular approach to design similar to that used in digital electronics is supported to facilitate the design of large complex systems. This tool is composed of a schematic capture unit, a simulator unit, and an evaluation unit. Starting with the definition of certain basic or integrated optical elements performing well-defined functions, a schematic capture unit helps to design specific functions. The simulator tool helps to verify the design and the evaluation tool determines its complexity. The usefulness of this design tool is demonstrated with an example design of a simple four- function arithmetic logic unit.

  19. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-substituted benzoquinoline nickel complex (generic). 721.5340 Section 721.5340 Protection of Environment...-substituted benzoquinoline nickel complex (generic). (a) Chemical substance and significant new uses subject...-substituted benzoquinoline nickel complex (PMN P-99-897) is subject to reporting under this section for...

  20. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-substituted benzoquinoline nickel complex (generic). 721.5340 Section 721.5340 Protection of Environment...-substituted benzoquinoline nickel complex (generic). (a) Chemical substance and significant new uses subject...-substituted benzoquinoline nickel complex (PMN P-99-897) is subject to reporting under this section for...

  1. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-substituted benzoquinoline nickel complex (generic). 721.5340 Section 721.5340 Protection of Environment...-substituted benzoquinoline nickel complex (generic). (a) Chemical substance and significant new uses subject...-substituted benzoquinoline nickel complex (PMN P-99-897) is subject to reporting under this section for...

  2. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-substituted benzoquinoline nickel complex (generic). 721.5340 Section 721.5340 Protection of Environment...-substituted benzoquinoline nickel complex (generic). (a) Chemical substance and significant new uses subject...-substituted benzoquinoline nickel complex (PMN P-99-897) is subject to reporting under this section for...

  3. 40 CFR 721.5340 - Substituted benzothiazole-azo-substituted benzoquinoline nickel complex (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-substituted benzoquinoline nickel complex (generic). 721.5340 Section 721.5340 Protection of Environment...-substituted benzoquinoline nickel complex (generic). (a) Chemical substance and significant new uses subject...-substituted benzoquinoline nickel complex (PMN P-99-897) is subject to reporting under this section for...

  4. 40 CFR 721.10497 - Substituted alkyl ester, hydrolysis products with silica and substituted silane (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkyl ester, hydrolysis... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10497 Substituted alkyl... alkyl ester, hydrolysis products with silica and substituted silane (PMNs P-06-276 and P-06-279)...

  5. 40 CFR 721.10497 - Substituted alkyl ester, hydrolysis products with silica and substituted silane (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... products with silica and substituted silane (generic). 721.10497 Section 721.10497 Protection of... ester, hydrolysis products with silica and substituted silane (generic). (a) Chemical substance and... alkyl ester, hydrolysis products with silica and substituted silane (PMNs P-06-276 and P-06-279)...

  6. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt (generic). 721.2577 Section 721.2577... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.2577 Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

  7. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt (generic). 721.2577 Section 721.2577... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.2577 Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

  8. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... significant new uses subject to reporting. (1) The chemical substances identified generically as...

  9. Oncogenicity of L-type amino-acid transporter 1 (LAT1) revealed by targeted gene disruption in chicken DT40 cells: LAT1 is a promising molecular target for human cancer therapy

    SciTech Connect

    Ohkawa, Mayumi; Ohno, Yoshiya; Masuko, Kazue; Takeuchi, Akiko; Suda, Kentaro; Kubo, Akihiro; Kawahara, Rieko; Okazaki, Shogo; Tanaka, Toshiyuki; Saya, Hideyuki; Seki, Masayuki; Enomoto, Takemi; Yagi, Hideki; Hashimoto, Yoshiyuki; Masuko, Takashi

    2011-03-25

    Highlights: {yields} We established LAT1 amino-acid transporter-disrupted DT40 cells. {yields} LAT1-disrupted cells showed slow growth and lost the oncogenicity. {yields} siRNA and mAb inhibited human tumor growth in vitro and in vivo. {yields} LAT1 is a promising target molecule for cancer therapy. -- Abstract: L-type amino-acid transporter 1 (LAT1) is the first identified light chain of CD98 molecule, disulfide-linked to a heavy chain of CD98. Following cDNA cloning of chicken full-length LAT1, we have constructed targeting vectors for the disruption of chicken LAT1 gene from genomic DNA of chicken LAT1 consisting of 5.4 kb. We established five homozygous LAT1-disrupted (LAT1{sup -/-}) cell clones, derived from a heterozygous LAT1{sup +/-} clone of DT40 chicken B cell line. Reactivity of anti-chicken CD98hc monoclonal antibody (mAb) with LAT1{sup -/-} DT40 cells was markedly decreased compared with that of wild-type DT40 cells. All LAT1{sup -/-} cells were deficient in L-type amino-acid transporting activity, although alternative-splice variant but not full-length mRNA of LAT1 was detected in these cells. LAT1{sup -/-} DT40 clones showed outstandingly slow growth in liquid culture and decreased colony-formation capacity in soft agar compared with wild-type DT40 cells. Cell-cycle analyses indicated that LAT1{sup -/-} DT40 clones have prolonged cell-cycle phases compared with wild-type or LAT1{sup +/-} DT40 cells. Knockdown of human LAT1 by small interfering RNAs resulted in marked in vitro cell-growth inhibition of human cancer cells, and in vivo tumor growth of HeLa cells in athymic mice was significantly inhibited by anti-human LAT1 mAb. All these results indicate essential roles of LAT1 in the cell proliferation and occurrence of malignant phenotypes and that LAT1 is a promising candidate as a molecular target of human cancer therapy.

  10. 37 CFR 1.125 - Substitute specification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... substitute specification includes no new matter. (c) A substitute specification submitted under this section must be submitted with markings showing all the changes relative to the immediate prior version of the specification of record. The text of any added subject matter must be shown by underlining the added text....

  11. 37 CFR 1.125 - Substitute specification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... substitute specification includes no new matter. (c) A substitute specification submitted under this section must be submitted with markings showing all the changes relative to the immediate prior version of the specification of record. The text of any added subject matter must be shown by underlining the added text....

  12. 5 CFR 1201.35 - Substituting parties.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Substituting parties. 1201.35 Section... AND PROCEDURES Procedures for Appellate Cases Parties, Representatives, and Witnesses § 1201.35 Substituting parties. (a) If an appellant dies or is otherwise unable to pursue the appeal, the processing...

  13. 5 CFR 1201.35 - Substituting parties.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Substituting parties. 1201.35 Section... AND PROCEDURES Procedures for Appellate Cases Parties, Representatives, and Witnesses § 1201.35 Substituting parties. (a) If an appellant dies or is otherwise unable to pursue the appeal, the processing...

  14. 24 CFR 235.206 - Substitute mortgagors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... MORTGAGE INSURANCE AND ASSISTANCE PAYMENTS FOR HOME OWNERSHIP AND PROJECT REHABILITATION Contract Rights and Obligations-Homes for Lower Income Families § 235.206 Substitute mortgagors. (a) Selling mortgagor... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors....

  15. Substitutes for Leadership: An Empirical Study.

    ERIC Educational Resources Information Center

    Howell, Jon P.; Dorfman, Peter W.

    The leadership substitutes hypothesis has been used to explain the occasional successes and frequent failures of leadership predictions. Three hypotheses were formulated to test the viability of the leadership substitutes concepts. Questionnaires were administered to hospital managers (N=63) and engineers (N=71). Instrumental and supportive leader…

  16. Carboranylmethylene-substituted phosphazenes and polymers thereof

    NASA Technical Reports Server (NTRS)

    Allcock, H. R.; Scopelianos, A. G. (Inventor)

    1984-01-01

    Carboranylmethylene-substituted cyclophosphazenes are described which can be thermally polymerized into carboranylmethylene-substituted phosphazene polymers. The polymers are useful as thermally stable coatings. Also, due to the characteristics of these polymers in acting as a ligand for transition metals, metalocarboranylmethylene phosphazene polymers are described which can act as immobilized catalyst systems, and are electrically conductive and superconductive.

  17. Substitute Teachers: Making Lost Days Count

    ERIC Educational Resources Information Center

    True, Charlene; Butler, Kyle; Sefton, Rachel

    2011-01-01

    As K-12 teachers and administrators grow increasingly concerned with issues of accountability, research-based methods, and intervention strategies, little discussion exists on the impact of substitute teachers in the classroom. In the rush to analyze test scores, are the days covered by substitute teachers even considered? Though districts are…

  18. Substitute Your Way to a Real Job

    ERIC Educational Resources Information Center

    Stephens, Cathy

    2013-01-01

    For some, substitute teaching is a career choice. However, for the majority of new teachers, it is often a necessary gateway to landing a first job. Either way, it is a great way to sharpen one's skills. This article presents tips from principals, teachers, and human resource directors to make the most of the substitute teaching experience…

  19. Educators Take Another Look at Substitutes

    ERIC Educational Resources Information Center

    Zubrzycki, Jaclyn

    2012-01-01

    The mythology surrounding the substitute teacher is not a pretty one: Paper airplanes, lost learning, bullying. But as schools collect more information about teacher absenteeism and its consequences, districts and schools are exploring ways to professionalize substitute teaching--or experiment with alternative ways of coping with teacher absences.…

  20. Synthesis of fluoro substituted quaterphenyl liquid crystals

    NASA Astrophysics Data System (ADS)

    Sasnouski, G.; Lapanik, V.; Bezborodov, V.; Dabrowski, R.; Dziaduszek, J.

    2014-08-01

    The improved approaches for the preparation of four ring quaterphenyl liquid crystalline compounds possessing fluoro substituted moieties have been developed. The key stage for the most synthetic schemes was the preparation of 3,6-diarylsubstituted cyclohex-2-en-1-ones via condensation of the corresponding aromatic Mannich salts with the fluoro substituted methyl benzyl ketone in the presence of base. The chlorination of these cyclohexenones with phosphorous pentachloride or methylation with methylmagnesium iodide followed oxidative aromatization allows the synthesis of final four ring fluoro substituted quaterphenyl liquid crystal (LC) compounds. Another approach provides for the condensation synthesis of bromo substituted intermediate terphenyls. They have been undergoing catalytic cross-coupling with the corresponding fluoro substituted phenyl boronic acid giving a wide range of quaterphenyl LC derivatives.

  1. Substitutional impurity in the graphene quantum dots

    NASA Astrophysics Data System (ADS)

    Sierański, K.; Szatkowski, J.

    2015-09-01

    The process of formation of the localized defect states due to substitutional impurity in sp2-bonded graphene quantum dot is considered using a simple tight-binding-type calculation. We took into account the interaction of the quantum dot atoms surrounding the substitutional impurity from the second row of elements. To saturate the external dangling sp2 orbitals of the carbon additionally 18 hydrogen atoms were introduced. The chemical formula of the quantum dot is H18C51X, where X is the symbol of substitutional atom. The position of the localized levels is determined relative to the host-atoms (C) εp energies. We focused on the effect of substitutional doping by the B, N and O on the eigenstate energies and on the total energy change of the graphene dots including for O the effect of lattice distorsion. We conclude that B, N, and O can form stable substitutional defects in graphene quantum dot.

  2. [Prophylaxis of dental caries using sugar substitutes].

    PubMed

    Eberle, G

    1984-12-01

    Among the three measures, which are capable of producing a preventive effect against caries only when applied combined, i.e. adequate fluoride supply, proper mouth hygiene and healthy nutrition, the latter is dealt with in greater detail. The use of sugar substitutes is discussed under the aspects of caries prevention, substitute composition and production technology as well as from a medical point of view. Among the presently available sugar substitutes with nutritive value are mentioned Xylite, Lycasine, Mannite, Sorbite, Palatinite, the non-calorific substitutes such as the natural Aspartame as well as the synthetic sweetening agents Saccharine and Cyclamate. The possibilities and limitations of using these sugar substitutes in the prevention of caries in adults and children are presented.

  3. Substituted Hydroxyapatites with Antibacterial Properties

    PubMed Central

    Kolmas, Joanna; Groszyk, Ewa; Kwiatkowska-Różycka, Dagmara

    2014-01-01

    Reconstructive surgery is presently struggling with the problem of infections located within implantation biomaterials. Of course, the best antibacterial protection is antibiotic therapy. However, oral antibiotic therapy is sometimes ineffective, while administering an antibiotic at the location of infection is often associated with an unfavourable ratio of dosage efficiency and toxic effect. Thus, the present study aims to find a new factor which may improve antibacterial activity while also presenting low toxicity to the human cells. Such factors are usually implemented along with the implant itself and may be an integral part of it. Many recent studies have focused on inorganic factors, such as metal nanoparticles, salts, and metal oxides. The advantages of inorganic factors include the ease with which they can be combined with ceramic and polymeric biomaterials. The following review focuses on hydroxyapatites substituted with ions with antibacterial properties. It considers materials that have already been applied in regenerative medicine (e.g., hydroxyapatites with silver ions) and those that are only at the preliminary stage of research and which could potentially be used in implantology or dentistry. We present methods for the synthesis of modified apatites and the antibacterial mechanisms of various ions as well as their antibacterial efficiency. PMID:24949423

  4. First principles investigation of substituted strontium hexaferrite

    NASA Astrophysics Data System (ADS)

    Dixit, Vivek

    This dissertation investigates how the magnetic properties of strontium hexaferrite change upon the substitution of foreign atoms at the Fe sites. Strontium hexaferrite, SrFe12O19, is a commonly used hard magnetic material and is produced in large quantities (around 500,000 tons per year). For different applications of strontium hexaferrite, its magnetic properties can be tuned by a proper substitution of the foreign atoms. Experimental screening for a proper substitution is a cost-intensive and time-consuming process, whereas computationally it can be done more efficiently. We used the 'density functional theory' a first principles based method to study substituted strontium hexaferrite. The site occupancies of the substituted atoms were estimated by calculating the substitution energies of different configurations. The formation probabilities of configurations were used to calculate the magnetic properties of substituted strontium hexaferrite. In the first study, Al-substituted strontium hexaferrite, SrFe12-x AlxO19 with x=0.5 and x=1.0 were investigated. It was found that at the annealing temperature the non-magnetic Al +3 ions preferentially replace Fe+3 ions from the 12 k and 2a sites. We found that the magnetization decreases and the magnetic anisotropy field increases as the fraction, x of the Al atoms increases. In the second study, SrFe12-xGaxO19 and SrFe12-xInxO19 with x=0.5 and x=1.0 were investigated. In the case of SrFe12-xGaxO19, the sites where Ga+3 ions prefer to enter are: 12 k, 2a, and 4f1. For SrFe12-xInxO19, In+3 ions most likely to occupy the 12k, 4f1 , and 4f2 sites. In both cases the magnetization was found to decrease slightly as the fraction of substituted atom increases. The magnetic anisotropy field increased for SrFe12-xGaxO 19, and decreased for SrFe12-xInxO19 as the concentration of substituted atoms increased. In the third study, 23 elements (M) were screened for their possible substitution in strontium hexaferrite, SrFe12-xMxO 19

  5. The terminal six amino-acids of the carboxy cytoplasmic tail of CD36 contain a functional domain implicated in the binding and capture of oxidized low-density lipoprotein.

    PubMed Central

    Malaud, Eric; Hourton, Delphine; Giroux, Louise Marie; Ninio, Ewa; Buckland, Robin; McGregor, John L

    2002-01-01

    CD36, a major adhesion molecule expressed by monocytes/macrophages, plays a key role in the binding and internalization of oxidized low-density lipoprotein (OxLDL). This adhesion molecule, a member of an important scavenger receptor family, contains a very short C-terminal cytoplasmic tail that is known to induce intracellular signalling events. However, the domains on the cytoplasmic tail involved in such signal transduction are unknown. In this study, we have investigated the functional components of the cytoplasmic tail by site-directed mutagenesis coupled with functional OxLDL and monoclonal antibody (mAb) binding studies. Seven truncated or punctual CD36 constructs, localized in the cytoplasmic tail, were produced by site-directed mutagenesis. Each construct was stably expressed in HEK293 cells. We used a quantitative and a qualitative method, labelling OxLDL with either iodine or rhodamine, to determine the functional importance of the cytoplasmic domains in OxLDL internalization. Results indicate that: (1) a deletion of the last amino-acid (construct K472STOP) significantly reduces, compared with wild-type, the binding, internalization and degradation of OxLDL; (2) truncation of the last six amino-acids (construct R467STOP) significantly reduces OxLDL binding; (3) the above two constructs (K472STOP and R467STOP) showed a reduced rate of OxLDL internalization compared with wild-type; (4) the binding and rate of internalization of an anti-CD36 monoclonal antibody (10/5) was not affected by the above mentioned mutants (K472STOP and R467STOP), compared with wild-type. This study shows, for the first time, a specific site on the CD36 cytoplasmic tail that is critical for the binding, endocytosis and targeting of OxLDL. PMID:12023894

  6. Modeling competitive substitution in a polyelectrolyte complex

    NASA Astrophysics Data System (ADS)

    Peng, B.; Muthukumar, M.

    2015-12-01

    We have simulated the invasion of a polyelectrolyte complex made of a polycation chain and a polyanion chain, by another longer polyanion chain, using the coarse-grained united atom model for the chains and the Langevin dynamics methodology. Our simulations reveal many intricate details of the substitution reaction in terms of conformational changes of the chains and competition between the invading chain and the chain being displaced for the common complementary chain. We show that the invading chain is required to be sufficiently longer than the chain being displaced for effecting the substitution. Yet, having the invading chain to be longer than a certain threshold value does not reduce the substitution time much further. While most of the simulations were carried out in salt-free conditions, we show that presence of salt facilitates the substitution reaction and reduces the substitution time. Analysis of our data shows that the dominant driving force for the substitution process involving polyelectrolytes lies in the release of counterions during the substitution.

  7. Modeling competitive substitution in a polyelectrolyte complex

    SciTech Connect

    Peng, B.; Muthukumar, M.

    2015-12-28

    We have simulated the invasion of a polyelectrolyte complex made of a polycation chain and a polyanion chain, by another longer polyanion chain, using the coarse-grained united atom model for the chains and the Langevin dynamics methodology. Our simulations reveal many intricate details of the substitution reaction in terms of conformational changes of the chains and competition between the invading chain and the chain being displaced for the common complementary chain. We show that the invading chain is required to be sufficiently longer than the chain being displaced for effecting the substitution. Yet, having the invading chain to be longer than a certain threshold value does not reduce the substitution time much further. While most of the simulations were carried out in salt-free conditions, we show that presence of salt facilitates the substitution reaction and reduces the substitution time. Analysis of our data shows that the dominant driving force for the substitution process involving polyelectrolytes lies in the release of counterions during the substitution.

  8. Amino acid substitutions in the thymidine kinase gene of induced acyclovir-resistant herpes simplex virus type 1

    NASA Astrophysics Data System (ADS)

    Hussin, Ainulkhir; Nor, Norefrina Shafinaz Md; Ibrahim, Nazlina

    2013-11-01

    Acyclovir (ACV) is an antiviral drug of choice in healthcare setting to treat infections caused by herpes viruses, including, but not limited to genital herpes, cold sores, shingles and chicken pox. Acyclovir resistance has emerged significantly due to extensive use and misuse of this antiviral in human, especially in immunocompromised patients. However, it remains unclear about the amino acid substitutions in thymidine (TK) gene, which specifically confer the resistance-associated mutation in herpes simplex virus. Hence, acyclovir-resistant HSV-1 was selected at high concentration (2.0 - 4.5 μg/mL), and the TK-gene was subjected to sequencing and genotypic characterization. Genotypic sequences comparison was done using HSV-1 17 (GenBank Accesion no. X14112) for resistance-associated mutation determination whereas HSV-1 KOS, HSV-1 473/08 and HSV clinical isolates sequences were used for polymorphism-associated mutation. The result showed that amino acid substitutions at the non-conserved region (UKM-1: Gln34Lys, UKM-2: Arg32Ser & UKM-5: Arg32Cys) and ATP-binding site (UKM-3: Tyr53End & UKM-4: Ile54Leu) of the TK-gene. These discoveries play an important role to extend another dimension to the evolution of acyclovir-resistant HSV-1 and suggest that selection at high ACV concentration induced ACV-resistant HSV-1 evolution. These findings also expand the knowledge on the type of mutations among acyclovir-resistant HSV-1. In conclusion, HSV-1 showed multiple strategies to exhibit acyclovir resistance, including amino acid substitutions in the TK gene.

  9. Sugar and sugar substitutes. Comparisons and indications.

    PubMed

    Alfin-Slater, R B; Pi-Sunyer, F X

    1987-08-01

    Public confusion and concern about the use of sugar and sugar substitutes are widespread. Physicians must be prepared to answer patients' inquiries about these substances. Some population groups should avoid certain sugar substitutes. In particular, pregnant women and young children should avoid saccharin, and phenylketonuric homozygous persons should avoid aspartame. In a varied, balanced diet, the use of aspartame and saccharin is one safe way for the general population to enjoy sweet foods with fewer calories and less cariogenic potential. Sugar substitutes may be helpful in dietary compliance for overweight and diabetic patients.

  10. Co-substitution of carbonate and fluoride in hydroxyapatite: Effect on substitution type and content

    NASA Astrophysics Data System (ADS)

    Zhu, Qing-Xia; Li, Ya-Ming; Han, Dan

    2015-04-01

    The nanosized hydroxyapatite substituted by fluoride and carbonate ions (CFHA) had been synthesized by aqueous precipitation method. CFHA had been considered as potential bone graft material for orthopedic and dental applications. The objective of this study was to determine the effects of simultaneously incorporated CO{3/2-} and F- on the substitution type and content. The morphologies of CFHAs were observed by TEM. The carbonate substitution type and content were characterized by FTIR. The fluoride contents were determined by F-selective electrode. The phase compositions and crystallinity of the samples were investigated by XRD. The fluoride and carbonate contents of CFHA increase with the dopant concentrations nonlinearly. The carbonate substitution has much more obvious effect on morphology compared with the fluoride substitution. The co-existence of CO{3/2-} and F- ions can influence the corresponding substitution fraction. The isomorphic substitution of sodium for calcium in the substitution process of CO{3/2-} can improve crystal degree and favor the B-type substitutions. Due to the closeness of the ion radii and equivalent substitution of F- and OH-, F- will occupy the OH- sites of HA crystals more easily, compelling most of the CO{3/2-} to be located in the B sites.

  11. Questioning nuclear waste substitution: a case study.

    PubMed

    Marshall, Alan

    2007-03-01

    This article looks at the ethical quandaries, and their social and political context, which emerge as a result of international nuclear waste substitution. In particular it addresses the dilemmas inherent within the proposed return of nuclear waste owned by Japanese nuclear companies and currently stored in the United Kingdom. The UK company responsible for this waste, British Nuclear Fuels Limited (BNFL), wish to substitute this high volume intermediate-level Japanese-owned radioactive waste for a much lower volume of much more highly radioactive waste. Special focus is given to ethical problems that they, and the UK government, have not wished to address as they move forward with waste substitution. The conclusion is that waste substitution can only be considered an ethical practice if a set of moderating conditions are observed by all parties. These conditions are listed and, as of yet, they are not being observed.

  12. Nutrient-substituted hydroxyapatites: synthesis and characterization

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.

    1999-01-01

    Incorporation of Mg, S, and plant-essential micronutrients into the structure of synthetic hydroxyapatite (HA) may be advantageous for closed-loop systems, such as will be required on Lunar and Martian outposts, because these apatites can be used as slow-release fertilizers. Our objective was to synthesize HA with Ca, P, Mg, S, Fe, Cu, Mn, Zn, Mo, B, and Cl incorporated into the structure, i.e., nutrient-substituted apatites. Hydroxyapatite, carbonate hydroxyapatite (CHA), nutrient-substituted hydroxyapatite (NHA), and nutrient-substituted carbonate hydroxyapatite (NCHA) were synthesized by precipitating from solution. Chemical and mineralogical analysis of precipitated samples indicated a considerable fraction of the added cations were incorporated into HA, without mineral impurities. Particle size of the HA was in the 1 to 40 nm range, and decreased with increased substitution of nutrient elements. The particle shape of HA was elongated in the c-direction in unsubstituted HA and NHA but more spherical in CHA and NCHA. The substitution of cations and anions in the HA structure was confirmed by the decrease of the d[002] spacing of HA with substitution of ions with an ionic radius less than that of Ca or P. The DTPA-extractable Cu ranged from 8 to 8429 mg kg-1, Zn ranged from 57 to 1279 mg kg-1, Fe from 211 to 2573 mg kg-1, and Mn from 190 to 1719 mg kg-1, depending on the substitution level of each element in HA. Nutrient-substituted HA has the potential to be used as a slow-release fertilizer to supply micronutrients, S, and Mg in addition to Ca and P.

  13. Chemical characterization of silicon-substituted hydroxyapatite.

    PubMed

    Gibson, I R; Best, S M; Bonfield, W

    1999-03-15

    Bioceramic specimens have been prepared by incorporating a small amount of silicon (0.4 wt %) into the structure of hydroxyapatite [Ca10(PO4)6(OH)2, HA] via an aqueous precipitation reaction to produce a silicon-substituted hydroxyapatite (Si-HA). The results of chemical analysis confirmed the proposed substitution of the silicon (or silicate) ion for the phosphorus (or phosphate) ion in hydroxyapatite. The Si-HA was produced by first preparing a silicon-substituted apatite (Si-Ap) by a precipitation process. A single-phase Si-HA was obtained by heating/calcining the as-prepared Si-Ap to temperatures above 700 degrees C; no secondary phases, such as tricalcium phosphate (TCP), tetracalcium phosphate (TeCP), or calcium oxide (CaO), were observed by X-ray diffraction analysis. Although the X-ray diffraction patterns of Si-HA and stoichiometric HA appeared to be identical, refinement of the diffraction data revealed some small structural differences between the two materials. The silicon substitution in the HA lattice resulted in a small decrease in the a axis and an increase in the c axis of the unit cell. This substitution also caused a decrease in the number of hydroxyl (OH) groups in the unit cell, which was expected from the proposed substitution mechanism. The incorporation of silicon in the HA lattice resulted in an increase in the distortion of the PO4 tetrahedra, indicated by an increase in the distortion index. Analysis of the Si-HA by Fourier transform infrared (FTIR) spectroscopy indicated that although the amount of silicon incorporated into the HA lattice was small, silicon substitution appeared to affect the FTIR spectra of HA, in particular the P-O vibrational bands. The results demonstrate that phase-pure silicon-substituted hydroxyapatite may be prepared using a simple precipitation technique.

  14. Improvement of the reverse tetracycline transactivator by single amino acid substitutions that reduce leaky target gene expression to undetectable levels

    PubMed Central

    Roney, Ian J.; Rudner, Adam D.; Couture, Jean-François; Kærn, Mads

    2016-01-01

    Conditional gene expression systems that enable inducible and reversible transcriptional control are essential research tools and have broad applications in biomedicine and biotechnology. The reverse tetracycline transcriptional activator is a canonical system for engineered gene expression control that enables graded and gratuitous modulation of target gene transcription in eukaryotes from yeast to human cell lines and transgenic animals. However, the system has a tendency to activate transcription even in the absence of tetracycline and this leaky target gene expression impedes its use. Here, we identify single amino-acid substitutions that greatly enhance the dynamic range of the system in yeast by reducing leaky transcription to undetectable levels while retaining high expression capacity in the presence of inducer. While the mutations increase the inducer concentration required for full induction, additional sensitivity-enhancing mutations can compensate for this effect and confer a high degree of robustness to the system. The novel transactivator variants will be useful in applications where tight and tunable regulation of gene expression is paramount. PMID:27323850

  15. A 10-amino-acid sequence in the N-terminal A/B domain of thyroid hormone receptor alpha is essential for transcriptional activation and interaction with the general transcription factor TFIIB.

    PubMed Central

    Hadzic, E; Desai-Yajnik, V; Helmer, E; Guo, S; Wu, S; Koudinova, N; Casanova, J; Raaka, B M; Samuels, H H

    1995-01-01

    The effects of the thyroid hormone (3,5,3'-triiodo-L-thyronine [T3]) on gene transcription are mediated by nuclear T3 receptors (T3Rs). alpha- and beta-isoform T3Rs (T3R alpha and -beta) are expressed from different genes and are members of a superfamily of ligand-dependent transcription factors that also includes the receptors for steroid hormones, vitamin D, and retinoids. Although T3 activates transcription by mediating a conformational change in the C-terminal approximately 220-amino-acid ligand-binding domain (LBD), the fundamental mechanisms of T3R-mediated transcriptional activation remain to be determined. We found that deletion of the 50-amino-acid N-terminal A/B domain of chicken T3R alpha (cT3R alpha) decreases T3-dependent stimulation of genes regulated by native thyroid hormone response elements about 10- to 20-fold. The requirement of the A/B region for transcriptional activation was mapped to amino acids 21 to 30, which contain a cluster of five basic amino acids. The A/B region of cT3R alpha is not required for T3 binding or for DNA binding of the receptor as a heterodimer with retinoid X receptor. In vitro binding studies indicate that the N-terminal region of cT3R alpha interacts efficiently with TFIIB and that this interaction requires amino acids 21 to 30 of the A/B region. In contrast, the LBD interacts poorly with TFIIB. The region of TFIIB primarily involved in the binding of cT3R alpha includes an amphipathic alpha helix contained within residues 178 to 201. Analysis using a fusion protein containing the DNA-binding domain of GAL4 and the entire A/B region of cT3R alpha suggests that this region does not contain an intrinsic activation domain. These and other studies indicate that cT3R alpha mediates at least some of its effects through TFIIB in vivo and that the N-terminal region of DNA-bound cT3R alpha acts to recruit and/or stabilize the binding of TFIIB to the transcription complex. T3 stimulation could then result from ligand

  16. A Sequential and Comprehensive Method for Effective Substitute Teaching

    ERIC Educational Resources Information Center

    Byer, John L.

    2008-01-01

    This article dealt with methods for making substitute teaching more effective. The purpose was to articulate a sequential method for maximizing the effectiveness of substitute teaching while providing substitutes with a comprehensive method for diligently and flexibly earning respect and using reflection to continually improve substitute teaching.…

  17. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  18. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  19. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). Link to an amendment published at 79 FR 34637, June 18, 2014. (a) Chemical... as substituted phenyl azo substituted phenyl esters (PMNs P-95-655, P-95-782 and P-95-871)...

  20. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  1. 40 CFR 721.3063 - Substituted phenyl azo substituted phenyl esters (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... phenyl esters (generic name). 721.3063 Section 721.3063 Protection of Environment ENVIRONMENTAL... esters (generic name). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as substituted phenyl azo substituted phenyl esters (PMNs...

  2. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic... phenyl) azo, sodium salt (PMN P-95-274) is subject to reporting under this section for the......

  3. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.5930 Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt...

  4. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.5930 Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt...

  5. 40 CFR 721.5930 - Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt (generic name). 721.5930 Section 721... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.5930 Phenylenebis[imino (chlorotriazinyl)imino(substituted naphthyl)azo(substituted phenyl)azo, sodium salt...

  6. Vitreous Substitutes: The Present and the Future

    PubMed Central

    Caprani, Simona Maria; Airaghi, Giulia; Bartalena, Luigi; Testa, Francesco; Mariotti, Cesare; Porta, Giovanni; Simonelli, Francesca

    2014-01-01

    Vitreoretinal surgery has advanced in numerous directions during recent years. The removal of the vitreous body is one of the main characteristics of this surgical procedure. Several molecules have been tested in the past to fill the vitreous cavity and to mimic its functions. We here review the currently available vitreous substitutes, focusing on their molecular properties and functions, together with their adverse effects. Afterwards we describe the characteristics of the ideal vitreous substitute. The challenges facing every ophthalmology researcher are to reach a long-term intraocular permanence of vitreous substitute with total inertness of the molecule injected and the control of inflammatory reactions. We report new polymers with gelification characteristics and smart hydrogels representing the future of vitreoretinal surgery. Finally, we describe the current studies on vitreous regeneration and cell cultures to create new intraocular gels with optimal biocompatibility and rheological properties. PMID:24877085

  7. Fluorinated oils as experimental vitreous substitutes.

    PubMed

    Miyamoto, K; Refojo, M F; Tolentino, F I; Fournier, G A; Albert, D M

    1986-07-01

    Two kinds of fluorinated oils (a fluorosilicone oil and a perfluoroether [Freon E15]) that have a higher density than water were evaluated as long-term vitreous substitutes. Vitreous compression using perfluoropropane gas was performed to create a space for the vitreous substitute in rabbit eyes. Two fluorosilicone oils (1000 and 10 000 centistokes) induced edema of the inner retinal layers and occasionally of the outer retinal layers regardless of viscosity or period of observation up to six months, but they were well tolerated clinically. Control eyes injected with silicone oils of comparable viscosities showed similar histopathologic findings. Freon E15 induced formation of bubbles and precipitates by one month after injection, and retinal disorganization, formation of preretinal membranes, and tractional retinal detachment by six months. Thus, Freon E15 proved to be unsuitable, but fluorosilicone oil is a possible high-density vitreous substitute.

  8. [Contingency management in opioid substitution treatment].

    PubMed

    Specka, M; Böning, A; Scherbaum, N

    2011-07-01

    The majority of opiate-dependent patients in substitution treatment show additional substance-related disorders. Concomitant use of heroin, alcohol, benzodiazepines or cocaine compromises treatment success. Concomitant drug use may be treated by using contingency management (CM) which is based on learning theory. In CM, abstinence from drugs, as verified by drug screenings, is reinforced directly and contingently. Reinforcers used in CM studies with substituted patients were, amongst others, vouchers and take-home privileges. Studies in the USA show a medium average effect of CM on drug consumption rates and abstinence. The effects decrease markedly after the end of the intervention. We discuss whether CM is applicable within the German substitution treatment system and how it can be combined with other interventions such as selective detoxification treatments or cognitive-behavioural programmes.

  9. Substituting telecommunications for travel - Feasible or desirable

    NASA Technical Reports Server (NTRS)

    Van Vleck, E. M.

    1974-01-01

    This paper reviews recent advances in telecommunications and examines the detailed structure of travel to estimate the feasibility of substituting telecommunications for various travel objectives. The impact of travel is analyzed from a social, economic, energy, and pollution standpoint to assess the desirability of substitution. Perhaps 35-50% of the nation's travel could, in theory, be replaced by very advanced telecommunications (such as a much improved large-screen teleconferencing network), but public resistance would be massive. Much economic dislocation would result since, for example, over 25% of retail sales are travel-related. The energy savings would be modest since only 25% of the nation's energy is consumed by transportation. However, all pollution would be reduced substantially since transportation accounts for 75% of the carbon monoxide, 60% of the hydrocarbon, and 55% of the nitrogen oxide pollution in the nation. Problems related to the implementation of large-scale substitution are discussed.

  10. Nonlinear self-adjointness through differential substitutions

    NASA Astrophysics Data System (ADS)

    Gandarias, M. L.

    2014-10-01

    It is known (Ibragimov, 2011; Galiakberova and Ibragimov, 2013) [14,18] that the property of nonlinear self-adjointness allows to associate conservation laws of the equations under study, with their symmetries. In this paper we show that, even when the equation is nonlinearly self-adjoint with a non differential substitution, finding the explicit form of the differential substitution can provide new conservation laws associated to its symmetries. By using the general theorem on conservation laws (Ibragimov, 2007) [11] and the property of nonlinear self-adjointness we find some new conservation laws for the modified Harry-Dym equation. By using a differential substitution we construct a conservation law for the Harry-Dym equation, which has not been derived before using Ibragimov method.

  11. Freeze substitution in 3 hours or less.

    PubMed

    McDonald, K L; Webb, R I

    2011-09-01

    Freeze substitution is a process for low temperature dehydration and fixation of rapidly frozen cells that usually takes days to complete. New methods for freeze substitution have been developed that require only basic laboratory tools: a platform shaker, liquid nitrogen, a metal block with holes for cryotubes and an insulated container such as an ice bucket. With this equipment, excellent freeze substitution results can be obtained in as little as 90 min for cells of small volume such as bacteria and tissue culture cells. For cells of greater volume or that have significant diffusion barriers such as cuticles or thick cell walls, one can extend the time to 3 h or more with dry ice. The 3-h method works well for all manner of specimens, including plants and Caenorhabditis elegans as well as smaller samples. Here, we present the basics of the techniques and some results from Nicotiana leaves, C. elegans adult worms, Escherichia coli and baby hamster kidney tissue culture cells.

  12. Graphane versus graphene: a computational investigation of the interaction of nucleobases, aminoacids, heterocycles, small molecules (CO2, H2O, NH3, CH4, H2), metal ions and onium ions.

    PubMed

    Umadevi, Deivasigamani; Narahari Sastry, G

    2015-11-11

    Graphane has emerged as a two-dimensional hydrocarbon with interesting physical properties and potential applications. Understanding the interaction of graphane with various molecules and ions is crucial to appreciate its potential applications. We investigated the interaction of nucleobases, aminoacids, saturated and unsaturated heterocycles, small molecules, metal ions and onium ions with graphane by using density functional theory calculations. The preferred orientations of these molecules and ions on the graphane surface have been analysed. The binding energies of graphane with these molecules have been compared with the corresponding binding energies of graphene. Our results reveal that graphane forms stable complexes with all the molecules and ions yet showing lesser binding affinity when compared to graphene. As an exemption, the preferential strong binding of H2O with graphane than graphene reveals the fact that graphane is more hydrophilic than graphene. Charge transfer between graphane and the molecules and ions have been found to be an important factor in determining the binding strength of the complexes. The effect of the interaction of these molecules and ions on the HOMO-LUMO energy gap of graphane has also been investigated.

  13. Resistance to cefepime and cefpirome due to a 4-amino-acid deletion in the chromosome-encoded AmpC beta-lactamase of a Serratia marcescens clinical isolate.

    PubMed

    Mammeri, Hedi; Poirel, Laurent; Bemer, Pascal; Drugeon, Henri; Nordmann, Patrice

    2004-03-01

    A multiresistant Serratia marcescens strain, HD, isolated from a patient with a urinary tract infection, was resistant to amino-, carboxy-, and ureidopenicillins, ceftazidime, and cefepime and was susceptible to cefotaxime and ceftriaxone, according to the guidelines of the NCCLS. No synergy was found between expanded-spectrum cephalosporins and clavulanic acid, according to the double-disk synergy test. The bla(AmpC) gene of the strain was amplified by PCR and cloned into Escherichia coli DH10B, giving rise to high-level resistance to ceftazidime, cefepime, and cefpirome. Sequencing analysis revealed that the bla(AmpC) gene from S. marcescens HD had a 12-nucleotide deletion compared to the bla(AmpC) gene from reference strain S. marcescens S3, leading to a 4-amino-acid deletion located in the H-10 helix of the beta-lactamase. Kinetic analysis showed that this enzyme significantly hydrolyzed ceftazidime, cefepime, and cefpirome. This work underlined that resistance to the latest expanded-spectrum cephalosporins may be mediated by structurally modified AmpC-type beta-lactamases.

  14. Resistance to Cefepime and Cefpirome Due to a 4-Amino-Acid Deletion in the Chromosome-Encoded AmpC β-Lactamase of a Serratia marcescens Clinical Isolate

    PubMed Central

    Mammeri, Hedi; Poirel, Laurent; Bemer, Pascal; Drugeon, Henri; Nordmann, Patrice

    2004-01-01

    A multiresistant Serratia marcescens strain, HD, isolated from a patient with a urinary tract infection, was resistant to amino-, carboxy-, and ureidopenicillins, ceftazidime, and cefepime and was susceptible to cefotaxime and ceftriaxone, according to the guidelines of the NCCLS. No synergy was found between expanded-spectrum cephalosporins and clavulanic acid, according to the double-disk synergy test. The blaAmpC gene of the strain was amplified by PCR and cloned into Escherichia coli DH10B, giving rise to high-level resistance to ceftazidime, cefepime, and cefpirome. Sequencing analysis revealed that the blaAmpC gene from S. marcescens HD had a 12-nucleotide deletion compared to the blaAmpC gene from reference strain S. marcescens S3, leading to a 4-amino-acid deletion located in the H-10 helix of the β-lactamase. Kinetic analysis showed that this enzyme significantly hydrolyzed ceftazidime, cefepime, and cefpirome. This work underlined that resistance to the latest expanded-spectrum cephalosporins may be mediated by structurally modified AmpC-type β-lactamases. PMID:14982755

  15. Resistance to cefepime and cefpirome due to a 4-amino-acid deletion in the chromosome-encoded AmpC beta-lactamase of a Serratia marcescens clinical isolate.

    PubMed

    Mammeri, Hedi; Poirel, Laurent; Bemer, Pascal; Drugeon, Henri; Nordmann, Patrice

    2004-03-01

    A multiresistant Serratia marcescens strain, HD, isolated from a patient with a urinary tract infection, was resistant to amino-, carboxy-, and ureidopenicillins, ceftazidime, and cefepime and was susceptible to cefotaxime and ceftriaxone, according to the guidelines of the NCCLS. No synergy was found between expanded-spectrum cephalosporins and clavulanic acid, according to the double-disk synergy test. The bla(AmpC) gene of the strain was amplified by PCR and cloned into Escherichia coli DH10B, giving rise to high-level resistance to ceftazidime, cefepime, and cefpirome. Sequencing analysis revealed that the bla(AmpC) gene from S. marcescens HD had a 12-nucleotide deletion compared to the bla(AmpC) gene from reference strain S. marcescens S3, leading to a 4-amino-acid deletion located in the H-10 helix of the beta-lactamase. Kinetic analysis showed that this enzyme significantly hydrolyzed ceftazidime, cefepime, and cefpirome. This work underlined that resistance to the latest expanded-spectrum cephalosporins may be mediated by structurally modified AmpC-type beta-lactamases. PMID:14982755

  16. [Substitution therapy tested against amphetamine dependence].

    PubMed

    Bloniecki Kallio, Victor; Guterstam, Joar; Franck, Johan

    2016-01-01

    Amphetamine dependence is relatively common in Sweden and it is the most frequently used substance among patients with intravenous drug abuse. Current treatment options are limited but recently substitution therapy with psychostimulant medication has been evaluated in several clinical trials. Such treatment is controversial in Sweden, perhaps due to the failure of experimental prescription of psychostimulants in the 1960s. Recent clinical trials however indicate that structured treatment programs with psychostimulants might have positive effects, although the results are inconsistent and the evidence base is still limited. Future research is needed in order to determine the potential role of substitution therapy for amphetamine dependence in clinical practice. PMID:26756343

  17. Generic Substitution Issues: Brand-generic Substitution, Generic-generic Substitution, and Generic Substitution of Narrow Therapeutic Index (NTI)/Critical Dose Drugs

    PubMed Central

    PAVELIU, Marian Sorin; BENGEA, Simona; PAVELIU, Fraga Silvia

    2011-01-01

    ABSTRACT Doctors accuse individual variability or lack of quality of generic drugs for adverse reactions or lack of efficacy. The variability of effect of generic substitution, although accepted by clinicians as possible, is little discussed or even understood by them. The situation is really serious in the case of generic substitution of drugs with narrow therapeutic index (NTI) or critical dose. In this paper we review the basic notions of variability and effectiveness of generic medication and change of attitude that would improve the use of these drugs. PMID:21977191

  18. Living skin substitutes: survival and function of fibroblasts seeded in a dermal substitute in experimental wounds.

    PubMed

    Lamme, E N; van Leeuwen, R T; Jonker, A; van Marle, J; Middelkoop, E

    1998-12-01

    The healing of full-thickness skin defects requires extensive synthesis and remodeling of dermal and epidermal components. Fibroblasts play an important role in this process and are being incorporated in the latest generation of artificial dermal substitutes. We studied the fate of fibroblasts seeded in our artificial elastin/collagen dermal substitute and the influence of the seeded fibroblasts on cell migration and dermal substitute degradation after transplantation to experimental full-thickness wounds in pigs. Wounds were treated with either dermal substitutes seeded with autologous fibroblasts or acellular substitutes. Seeded fibroblasts, labeled with a PKH-26 fluorescent cell marker, were detected in the wounds with fluorescence microscopy and quantitated with flow cytofluorometric analysis of single-cell suspensions of wound tissue. The cellular infiltrate was characterized for the presence of mesenchymal cells (vimentin), monocytes/macrophages, and vascular cells. Dermal substitute degradation was quantitated by image analysis of wound sections stained with Herovici's staining. In the wounds treated with the seeded dermal substitute, fluorescent PKH-26-labeled cells were detectable up to 6 d and were positive for vimentin but not for the macrophage antibody. After 5 d, flow cytofluorometry showed the presence of 3.1 (+/-0.9) x 10(6) (mean +/- SD, n = 7) PKH-26-positive cells in these wounds, whereas initially only 1 x 10(6) fluorescent fibroblasts had been seeded. In total, the percentage of mesenchymal cells minus the macrophages was similar after 5 d between wounds treated with the seeded and the acellular substitutes. In the wounds treated with the seeded substitute, however, 19.5% of the mesenchymal cells were of seeded origin. Furthermore, the rate of substitute degradation in the seeded wounds was significantly lower at 2-4 wk after wounding than in wounds treated with the acellular substitute. Vascular in-growth and the number of infiltrated

  19. Syntheses of novel substituted-boranophosphate nucleosides.

    PubMed

    Vyakaranam, Kamesh; Rana, Geeta; Spielvogel, Bernard F; Maguire, John A; Hosmane, Narayan S

    2002-01-01

    A number of substituted (borano) nucleic acids, 3'-[diethylphosphite(cyano, carboxy, or carbamoyl) borano] deoxynucleosides (3a-4c) and 5'-[diethylphosphite(cyano or carboxy) borano] deoxynucleosides (6a-7d) were prepared by a variety of synthetic procedures. The syntheses of the pyrophosphates (2a-2c), as precursors for 3a-4c, are also described. PMID:12484452

  20. Capillary Electrophoresis of Substituted Benzoic Acids

    ERIC Educational Resources Information Center

    Mills, Nancy S.; Spence, John D.; Bushey, Michelle M.

    2005-01-01

    A series of substituted benzoic acids (SBAs) are prepared by students. The pKa shift, a result of the electron-withdrawing or electron-donating characteristics of the subsistent is examined in reference to the electrophoretic migration behavior of benzoic acid.

  1. The Substitution-Elimination Mechanistic Disc Method

    ERIC Educational Resources Information Center

    Buonora, Paul T.; Yu Jin Lim

    2004-01-01

    A method designed to facilitate prediction of mechanism and products by developing critical thinking skills and reducing memorization is presented. The mechanistic disc method requiring students to utilize their understanding of charge stabilization, structural organic chemistry, and the fundamental mechanisms of aliphatic substitution and…

  2. 25 CFR 522.9 - Substitute approval.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to... the date of submission to the Chairman, a tribal ordinance or resolution shall be considered to...

  3. 25 CFR 522.9 - Substitute approval.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to... the date of submission to the Chairman, a tribal ordinance or resolution shall be considered to...

  4. 25 CFR 522.9 - Substitute approval.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to... the date of submission to the Chairman, a tribal ordinance or resolution shall be considered to...

  5. 25 CFR 522.9 - Substitute approval.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to... the date of submission to the Chairman, a tribal ordinance or resolution shall be considered to...

  6. 25 CFR 522.9 - Substitute approval.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR APPROVAL OF CLASS II AND CLASS III ORDINANCES AND RESOLUTIONS SUBMISSION OF GAMING ORDINANCE OR RESOLUTION § 522.9 Substitute approval. If the Chairman fails to... the date of submission to the Chairman, a tribal ordinance or resolution shall be considered to...

  7. Trends in Autism Prevalence: Diagnostic Substitution Revisited

    ERIC Educational Resources Information Center

    Coo, Helen; Ouellette-Kuntz, Helene; Lloyd, Jennifer E. V.; Kasmara, Liza; Holden, Jeanette J. A.; Lewis, M. E. Suzanne

    2008-01-01

    There has been little evidence to support the hypothesis that diagnostic substitution may contribute to increases in the administrative prevalence of autism. We examined trends in assignment of special education codes to British Columbia (BC) school children who had an autism code in at least 1 year between 1996 and 2004, inclusive. The proportion…

  8. The Approval Plan: Selection Aid, Selection Substitute

    ERIC Educational Resources Information Center

    Fenner, Audrey

    2004-01-01

    Approval plans are used by many libraries as an adjunct to title-by-title selection, and sometimes as a substitute for it. The author examines this approach to purchasing library materials, considering positive and negative effects approval plans may have on collection balance as well as on acquisitions budgets and workflow. The article also…

  9. The first arsenido-substituted niobocene derivative

    SciTech Connect

    Nikonov, G.I.; Lemenovskii, D.A.; Lorberth, J.

    1995-04-26

    Synthesis and structural characterization of arsenide substitued niobocene hydrides is reported. The direct substitution of the organic arsenides for hydride ligands is accomplished using halogenated arsenide precursors. NMR, IR, and X-ray crystallography is used in the structural characterization of these compounds. The molecular structure of Cp{sub 2}NbH{sub 2}AsEt{sub 2}is reported.

  10. Syntheses of novel substituted-boranophosphate nucleosides.

    PubMed

    Vyakaranam, Kamesh; Rana, Geeta; Spielvogel, Bernard F; Maguire, John A; Hosmane, Narayan S

    2002-01-01

    A number of substituted (borano) nucleic acids, 3'-[diethylphosphite(cyano, carboxy, or carbamoyl) borano] deoxynucleosides (3a-4c) and 5'-[diethylphosphite(cyano or carboxy) borano] deoxynucleosides (6a-7d) were prepared by a variety of synthetic procedures. The syntheses of the pyrophosphates (2a-2c), as precursors for 3a-4c, are also described.

  11. 24 CFR 203.258 - Substitute mortgagors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... December 15, 1989; or (2) In accordance with the Direct Endorsement program, where the underwriter of the... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Substitute mortgagors....

  12. 24 CFR 203.258 - Substitute mortgagors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... URBAN DEVELOPMENT MORTGAGE AND LOAN INSURANCE PROGRAMS UNDER NATIONAL HOUSING ACT AND OTHER AUTHORITIES... December 15, 1989; or (2) In accordance with the Direct Endorsement program, where the underwriter of the... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Substitute mortgagors....

  13. 21 CFR 882.5910 - Dura substitute.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dura substitute. 882.5910 Section 882.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... surrounding the brain). (b) Classification. Class II (performance standards)....

  14. 21 CFR 882.5910 - Dura substitute.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dura substitute. 882.5910 Section 882.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... surrounding the brain). (b) Classification. Class II (performance standards)....

  15. 21 CFR 882.5910 - Dura substitute.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dura substitute. 882.5910 Section 882.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... surrounding the brain). (b) Classification. Class II (performance standards)....

  16. 24 CFR 220.253 - Substitute mortgagors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... MORTGAGE INSURANCE AND INSURED IMPROVEMENT LOANS FOR URBAN RENEWAL AND CONCENTRATED DEVELOPMENT AREAS... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Substitute mortgagors. 220.253 Section 220.253 Housing and Urban Development Regulations Relating to Housing and Urban...

  17. 24 CFR 220.253 - Substitute mortgagors.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... MORTGAGE INSURANCE AND INSURED IMPROVEMENT LOANS FOR URBAN RENEWAL AND CONCENTRATED DEVELOPMENT AREAS... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Substitute mortgagors. 220.253 Section 220.253 Housing and Urban Development Regulations Relating to Housing and Urban...

  18. 24 CFR 220.253 - Substitute mortgagors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... MORTGAGE INSURANCE AND INSURED IMPROVEMENT LOANS FOR URBAN RENEWAL AND CONCENTRATED DEVELOPMENT AREAS... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Substitute mortgagors. 220.253 Section 220.253 Housing and Urban Development Regulations Relating to Housing and Urban...

  19. 24 CFR 220.253 - Substitute mortgagors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... MORTGAGE INSURANCE AND INSURED IMPROVEMENT LOANS FOR URBAN RENEWAL AND CONCENTRATED DEVELOPMENT AREAS... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Substitute mortgagors. 220.253 Section 220.253 Housing and Urban Development Regulations Relating to Housing and Urban...

  20. 24 CFR 220.253 - Substitute mortgagors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... MORTGAGE INSURANCE AND INSURED IMPROVEMENT LOANS FOR URBAN RENEWAL AND CONCENTRATED DEVELOPMENT AREAS... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Substitute mortgagors. 220.253 Section 220.253 Housing and Urban Development Regulations Relating to Housing and Urban...

  1. Implicit Semantic Perception in Object Substitution Masking

    ERIC Educational Resources Information Center

    Goodhew, Stephanie C.; Visser, Troy A. W.; Lipp, Ottmar V.; Dux, Paul E.

    2011-01-01

    Decades of research on visual perception has uncovered many phenomena, such as binocular rivalry, backward masking, and the attentional blink, that reflect "failures of consciousness". Although stimuli do not reach awareness in these paradigms, there is evidence that they nevertheless undergo semantic processing. Object substitution masking (OSM),…

  2. Multisensory perceptual learning and sensory substitution.

    PubMed

    Proulx, Michael J; Brown, David J; Pasqualotto, Achille; Meijer, Peter

    2014-04-01

    One of the most exciting recent findings in neuroscience has been the capacity for neural plasticity in adult humans and animals. Studies of perceptual learning have provided key insights into the mechanisms of neural plasticity and the changes in functional neuroanatomy that it affords. Key questions in this field of research concern how practice of a task leads to specific or general improvement. Although much of this work has been carried out with a focus on a single sensory modality, primarily visual, there is increasing interest in multisensory perceptual learning. Here we will examine how advances in perceptual learning research both inform and can be informed by the development and advancement of sensory substitution devices for blind persons. To allow 'sight' to occur in the absence of visual input through the eyes, visual information can be transformed by a sensory substitution device into a representation that can be processed as sound or touch, and thus give one the potential to 'see' through the ears or tongue. Investigations of auditory, visual and multisensory perceptual learning can have key benefits for the advancement of sensory substitution, and the study of sensory deprivation and sensory substitution likewise will further the understanding of perceptual learning in general and the reverse hierarchy theory in particular. It also has significant importance for the developing understanding of the brain in metamodal terms, where functional brain areas might be best defined by the computations they carry out rather than by their sensory-specific processing role. PMID:23220697

  3. Coal as a Substitute for Carbon Black

    NASA Technical Reports Server (NTRS)

    Kushida, R. O.

    1982-01-01

    New proposal shows sprayed coal powder formed by extrusion of coal heated to plastic state may be inexpensive substitute for carbon black. Carbon black is used extensively in rubber industry as reinforcing agent in such articles as tires and hoses. It is made from natural gas and petroleum, both of which are in short supply.

  4. 24 CFR 221.252 - Substitute mortgagors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... LOW COST AND MODERATE INCOME MORTGAGE INSURANCE-SAVINGS CLAUSE Contract Rights and Obligations-Low... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Substitute mortgagors. 221.252 Section 221.252 Housing and Urban Development Regulations Relating to Housing and Urban...

  5. Multisensory perceptual learning and sensory substitution.

    PubMed

    Proulx, Michael J; Brown, David J; Pasqualotto, Achille; Meijer, Peter

    2014-04-01

    One of the most exciting recent findings in neuroscience has been the capacity for neural plasticity in adult humans and animals. Studies of perceptual learning have provided key insights into the mechanisms of neural plasticity and the changes in functional neuroanatomy that it affords. Key questions in this field of research concern how practice of a task leads to specific or general improvement. Although much of this work has been carried out with a focus on a single sensory modality, primarily visual, there is increasing interest in multisensory perceptual learning. Here we will examine how advances in perceptual learning research both inform and can be informed by the development and advancement of sensory substitution devices for blind persons. To allow 'sight' to occur in the absence of visual input through the eyes, visual information can be transformed by a sensory substitution device into a representation that can be processed as sound or touch, and thus give one the potential to 'see' through the ears or tongue. Investigations of auditory, visual and multisensory perceptual learning can have key benefits for the advancement of sensory substitution, and the study of sensory deprivation and sensory substitution likewise will further the understanding of perceptual learning in general and the reverse hierarchy theory in particular. It also has significant importance for the developing understanding of the brain in metamodal terms, where functional brain areas might be best defined by the computations they carry out rather than by their sensory-specific processing role.

  6. 40 CFR 192.42 - Substitute provisions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Substitute provisions. 192.42 Section 192.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION... provide at least an equivalent level of protection for human health and the environment....

  7. 40 CFR 192.42 - Substitute provisions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Substitute provisions. 192.42 Section 192.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION... provide at least an equivalent level of protection for human health and the environment....

  8. 40 CFR 192.42 - Substitute provisions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Substitute provisions. 192.42 Section 192.42 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) RADIATION PROTECTION... provide at least an equivalent level of protection for human health and the environment....

  9. The Energy of Substituted Ethanes. Asymmetry Orbitals

    PubMed Central

    Salem, Lionel; Hoffmann, Roald; Otto, Peter

    1973-01-01

    The leading terms in the energy of a general substituted ethane are derived in explicit form as a function of the torsional angle θ, the substituent electronegativities, and their mutual overlaps. The energy is found to be the sum of all four overlaps between pairs of asymmetry orbitals, and satisfies the requisite symmetry properties. PMID:16592060

  10. Substitute or Complement?: Spousal Influence on Volunteering

    ERIC Educational Resources Information Center

    Rotolo, Thomas; Wilson, John

    2006-01-01

    Social scientists have documented the influence of family statuses on volunteering, ignoring intrafamily effects. Using newly issued data from the Current Population Survey on the volunteer behavior of 19,626 American couples, we test two competing theories concerning spousal influences on volunteering. Substitution theory predicts that spouses…

  11. 21 CFR 882.5910 - Dura substitute.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dura substitute. 882.5910 Section 882.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... surrounding the brain). (b) Classification. Class II (performance standards)....

  12. 21 CFR 882.5910 - Dura substitute.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dura substitute. 882.5910 Section 882.5910 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL... surrounding the brain). (b) Classification. Class II (performance standards)....

  13. Substitution treatment for opioid addicts in Germany

    PubMed Central

    Michels, Ingo Ilja; Stöver, Heino; Gerlach, Ralf

    2007-01-01

    Background After a long and controversial debate methadone maintenance treatment (MMT) was first introduced in Germany in 1987. The number of patients in MMT – first low because of strict admission criteria – increased considerably since the 1990s up to some 65,000 at the end of 2006. In Germany each general practitioner (GP), who has completed an additional training in addiction medicine, is allowed to prescribe substitution drugs to opioid dependent patients. Currently 2,700 GPs prescribe substitution drugs. Psychosocial care should be made available to all MMT patients. Results The results of research studies and practical experiences clearly indicate that patients benefit substantially from MMT with improvements in physical and psychological health. MMT proves successful in attaining high retention rates (65 % to 85 % in the first years, up to 50 % after more than seven years) and plays a major role in accessing and maintaining ongoing medical treatment for HIV and hepatitis. MMT is also seen as a vital factor in the process of social re-integration and it contributes to the reduction of drug related harms such as mortality and morbidity and to the prevention of infectious diseases. Some 10 % of MMT patients become drug-free in the long run. Methadone is the most commonly prescribed substitution medication in Germany, although buprenorphine is attaining rising importance. Access to MMT in rural areas is very patchy and still constitutes a problem. There are only few employment opportunities for patients participating in MMT, although regular employment is considered unanimously as a positive factor of treatment success. Substitution treatment in German prisons is heterogeneous in access and treatment modalities. Access is very patchy and the number of inmates in treatment is limited. Nevertheless, substitution treatment plays a substantial part in the health care system provided to drug users in Germany. Conclusion In Germany, a history of substitution

  14. Signalization and stimulus-substitution in Pavlov's theory of conditioning.

    PubMed

    García-Hoz, Víctor

    2003-11-01

    The concept of conditioning as signalization proposed by Ivan P. Pavlov (1927, 1928) is studied in relation to the theory of stimulus-substitution, which is also attributed to him. In the so-called theory of stimulus-substitution a distinction must be made between an empirical principle of substitution and an actual theory of substitution, which can adopt different forms. The Pavlovian theory of substitution--which conceives substitution as a substitution of the unconditioned stimulus (US) by the conditioned stimulus (CS) in the activation of the representation of the former--can be understood as an explanation or model of signalization. Signalization and substitution are answers to different questions, and the level of analysis to which signalization corresponds, is that which concerns the nature of conditioning as an operation of the animal in the environment.

  15. Signalization and stimulus-substitution in Pavlov's theory of conditioning.

    PubMed

    García-Hoz, Víctor

    2003-11-01

    The concept of conditioning as signalization proposed by Ivan P. Pavlov (1927, 1928) is studied in relation to the theory of stimulus-substitution, which is also attributed to him. In the so-called theory of stimulus-substitution a distinction must be made between an empirical principle of substitution and an actual theory of substitution, which can adopt different forms. The Pavlovian theory of substitution--which conceives substitution as a substitution of the unconditioned stimulus (US) by the conditioned stimulus (CS) in the activation of the representation of the former--can be understood as an explanation or model of signalization. Signalization and substitution are answers to different questions, and the level of analysis to which signalization corresponds, is that which concerns the nature of conditioning as an operation of the animal in the environment. PMID:14628703

  16. SUBSTITUTION OF CADMIUM CYANIDE ELECTROPLATING WITH ZINC CHLORIDE ELECTROPLATING

    EPA Science Inventory

    The study evaluated the zinc chloride electroplating process as a substitute for cadmium cyanide electroplating in the manufacture of industrial connectors and fittings at Aeroquip Corporation. The process substitution eliminates certain wastes, specifically cadmium and cyanide, ...

  17. Design of a thermophotovoltaic battery substitute

    NASA Astrophysics Data System (ADS)

    Doyle, Edward F.; Becker, Frederick E.; Shukla, Kailash C.; Fraas, Lewis M.

    1999-03-01

    Many military platforms that currently use the BA-5590 primary battery or the BB-390A/U rechargeable battery are limited in performance by low storage capacity and long recharge times. Thermo Power Corporation, with team members JX Crystals and Essential Research Inc. is developing an advanced thermophotovoltaic (TPV) battery substitute that will provide higher storage capacity, lower weight, and instantaneous recharging (by refueling). The TPV battery substitute incorporates several advanced design features including: an evacuated and sealed enclosure for the emitter and PV cells to minimize unwanted convection heat transfer from the emitter to PV cells; selective tungsten emitter with a well matched gallium antimonide PV cell receiver; optical filter to recycle nonconvertible radiant energy; and a silicon carbide thermal recuperator to recover thermal energy from exhaust gases.

  18. Generic substitution: issues for problematic drugs.

    PubMed

    Henderson, J D; Esham, R H

    2001-01-01

    The methodology and criteria for bioequivalence testing have been firmly established by the Food and Drug Administration (FDA). For certain drugs with a narrow therapeutic index (e.g., digoxin, levothyroxine, warfarin), generic substitution may not be advisable or even allowable, depending on the substitution laws of individual states. Digoxin and levothyroxine tablets are examples of drugs for which no New Drug Applications (NDAs) currently exist. However, commercially available generic products for both of these drugs have not been determined by the FDA to be therapeutically equivalent to the innovator products. Generic versions of warfarin have been approved by the FDA as being therapeutically equivalent to the innovator products, as have generic versions of the rescue inhaler albuterol. Yet, misinformation and myths persist regarding the adequacy and proven reliability of the FDA's determination of bioequivalence for these products.

  19. Synthesis of substituted [8]cycloparaphenylenes by [2 + 2 + 2] cycloaddition.

    PubMed

    Tran-Van, Anne-Florence; Huxol, Elena; Basler, Jonathan M; Neuburger, Markus; Adjizian, Jean-Joseph; Ewels, Chris P; Wegner, Hermann A

    2014-03-21

    A new modular approach to the smallest substituted cycloparaphenylenes (CPPs) is presented. This versatile method permits access to substituted CPPs, choosing the substituent at a late stage of the synthesis. Variously substituted [8]CPPs have been synthesized, and their properties analyzed. The structural characteristics of substituted CPPs are close to those of unsubstituted CPPs. However, their optoelectronic behavior differs remarkably due to the larger torsion angle between the phenyl units. PMID:24597661

  20. Multifunctional optical processor based on symbolic substitution

    SciTech Connect

    Casasent, D.P.; Botha, E.C. )

    1989-04-01

    The authors propose an optical multifunctional processor that can perform logic, numeric, pattern recognition, morphological, and inference operations. The ability to perform such diverse functions on one optical processor architecture is unique. The processor uses the technique of symbolic substitution and is based on an optical correlator architecture. Several inputs can be operated on in parallel, and different functions can be performed at one time, making it a multiple-instruction multiple-data processor.

  1. Oxidation of Terthiophene Substituted with Ferrocenyl Groups

    NASA Astrophysics Data System (ADS)

    Sato, Masa-aki; Kashiwagi, Shin-ichiro; Taniguchi, Hiroyuki; Hiroi, Masao

    1999-09-01

    Terthiophenes substituted with ferrocenyl or methyl groups were prepared by a palladium-catalyzed cross-coupling reaction. The oxidation processes and the oxidized states of the compounds were investigated by cyclic voltammetry, coulometry, and electronic absorption spectroscopy. The first oxidation of the ferrocenyl-terthiophenes took place on the ferrocene moiety; the resultant oxidized states spread over the terthiophene moiety. This implies the charge transfer from the ferricinium ion moiety to the terthiophene moiety.

  2. [Current aspects in red blood cell substitutes].

    PubMed

    Wang, Yanfeng; Pan, Jilun; Yu, Yaoting

    2004-06-01

    Red blood cell substitutes are a group of oxygen carriers designed to temporarily replace transfused blood. Current developing products include perfluorocarbon-based and hemoglobin-based oxygen carrier. Each product is unique in its limitations and advantages. A number of products are in advanced clinical trials and nearing market. When they are available for use it is likely that development will accelerate and even better products will substantially alleviate the world-wide shortage of blood for transfusion.

  3. Substituted barium ferrites; sources of anisotropy

    NASA Astrophysics Data System (ADS)

    Morrish, A. H.; Zhou, X. Z.; Yang, Zheng; Zeng, Hua-Xian

    1994-12-01

    The substituted barium ferrites BaFe12-2 xCo x Sn x O19 (0 ≤ x ≤ 1.4) and BaFe1-2xCo x O19 (0 ≤ x ≤ 0.9) have been studied. The site occupancies, as determined from Mössbauer spectra, have been used to interpret the changes in the magnetization and in the crystalline anisotropy.

  4. [Clastogenic activity of dietary sugar substitutes].

    PubMed

    Durnev, A D; Oreshchenko, A V; Kulakova, A V; Beresten', N F; Seredenin, S B

    1995-01-01

    The present paper describes the possible clastogenic activity of the following synthetic sugar substitutes, such as cyclamate in daily doses of 11 and 110 mg/kg, saccharin, 5 and 50 mg/kg, acesulfam, 15 and 150 mg/kg, sucralose, 15 and 150 mg/kg, aspartame, 40 and 400 mg/kg, orally given to C57Bl/6 mice during 5 days. No clastogenic activity was found in the compounds tested.

  5. Intersection Type Systems and Explicit Substitutions Calculi

    NASA Astrophysics Data System (ADS)

    Ventura, Daniel Lima; Ayala-Rincón, Mauricio; Kamareddine, Fairouz

    The λ-calculus with de Bruijn indices, called λ dB , assembles each α-class of λ-terms into a unique term, using indices instead of variable names. Intersection types provide finitary type polymorphism satisfying important properties like principal typing, which allows the type system to include features such as data abstraction (modularity) and separate compilation. To be closer to computation and to simplify the formalisation of the atomic operations involved in β-contractions, several explicit substitution calculi were developed most of which are written with de Bruijn indices. Although untyped and simply types versions of explicit substitution calculi are well investigated, versions with more elaborate type systems (e.g., with intersection types) are not. In previous work, we presented a version for λ dB of an intersection type system originally introduced to characterise principal typings for β-normal forms and provided the characterisation for this version. In this work we introduce intersection type systems for two explicit substitution calculi: the λσ and the λs e . These type system are based on a type system for λ dB and satisfy the basic property of subject reduction, which guarantees the preservation of types during computations.

  6. Variance estimation for nucleotide substitution models.

    PubMed

    Chen, Weishan; Wang, Hsiuying

    2015-09-01

    The current variance estimators for most evolutionary models were derived when a nucleotide substitution number estimator was approximated with a simple first order Taylor expansion. In this study, we derive three variance estimators for the F81, F84, HKY85 and TN93 nucleotide substitution models, respectively. They are obtained using the second order Taylor expansion of the substitution number estimator, the first order Taylor expansion of a squared deviation and the second order Taylor expansion of a squared deviation, respectively. These variance estimators are compared with the existing variance estimator in terms of a simulation study. It shows that the variance estimator, which is derived using the second order Taylor expansion of a squared deviation, is more accurate than the other three estimators. In addition, we also compare these estimators with an estimator derived by the bootstrap method. The simulation shows that the performance of this bootstrap estimator is similar to the estimator derived by the second order Taylor expansion of a squared deviation. Since the latter one has an explicit form, it is more efficient than the bootstrap estimator.

  7. Advancing safer alternatives through functional substitution.

    PubMed

    Tickner, Joel A; Schifano, Jessica N; Blake, Ann; Rudisill, Catherine; Mulvihill, Martin J

    2015-01-20

    To achieve the ultimate goal of sustainable chemicals management policy–the transition to safer chemicals, materials, products, and processes–current chemicals management approaches could benefit from a broader perspective. Starting with considerations of function, rather than characterizing and managing risks associated with a particular chemical, may provide a different, solutions-oriented lens to reduce risk associated with the uses of chemicals. It may also offer an efficient means, complementing existing tools, to reorient chemicals management approaches from time-intensive risk assessment and risk management based on single chemicals to comparative evaluation of the best options to fulfill a specific function. This article describes a functional approach to chemicals management we call “functional substitution” that encourages decision-makers to look beyond chemical by chemical substitution to find a range of alternatives to meet product performance. We define functional substitution, outline a rationale for greater use of this concept when considering risks posed by uses of chemicals, and provide examples of how functional approaches have been applied toward the identification of alternatives. We also discuss next steps for implementing functional substitution in chemical assessment and policy development.

  8. Magnetic properties of metal-substituted haematite

    NASA Astrophysics Data System (ADS)

    Wells, M. A.; Fitzpatrick, R. W.; Gilkes, R. J.; Dobson, J.

    1999-08-01

    Mineral and isothermal magnetic properties of Al-, Mn- and Ni-substituted haematites were characterized and their relationships evaluated in order to interpret better the results of magnetic analyses of soils and recent sediments. Aluminium, manganese and nickel haematites generally behaved as single-domain (SD) particles. The influence of incorporated Al on the magnetic behaviour of haematite was consistent with Al acting as a paramagnetic dilutent. Mass magnetic susceptibility (chi) and SIRM_800 decreased as the level of Al substitution increased. Incorporation of Mn and Ni increased chi, which could be associated with enhancement of the spin canting effect of haematite. The stability of SIRM_800 to demagnetization for Al-haematite appears to be related to a defect mechanism associated with the development of smaller crystallites arising from Al substitution. Magnetic domain rotation or flipping was probably inhibited, being blocked by structural defects during magnetization and demagnetization, and resulted in a low but stable partial SIRM (SIRM_800). %IRM/SIRM_800 demagnetization curves and estimated (B_o)_CR values of <=100 mT for Mn-haematite indicate pseudo-single-domain/multidomain-like behaviour despite Mn-haematite having particle and crystallite dimensions similar to Ni-haematite, which did not show this behaviour. Data indicate that parameters involving unsaturated, partial SIRM should be used with caution in magnetic studies of soils and sediments.

  9. 40 CFR 721.4365 - Substituted ethoxylated hydrocarbon (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted ethoxylated hydrocarbon... Specific Chemical Substances § 721.4365 Substituted ethoxylated hydrocarbon (generic). (a) Chemical... as Substituted ethoxylated hydrocarbon (PMN P-99-0313) is subject to reporting under this section...

  10. 40 CFR 721.4365 - Substituted ethoxylated hydrocarbon (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted ethoxylated hydrocarbon... Specific Chemical Substances § 721.4365 Substituted ethoxylated hydrocarbon (generic). (a) Chemical... as Substituted ethoxylated hydrocarbon (PMN P-99-0313) is subject to reporting under this section...

  11. 40 CFR 721.4365 - Substituted ethoxylated hydrocarbon (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted ethoxylated hydrocarbon... Specific Chemical Substances § 721.4365 Substituted ethoxylated hydrocarbon (generic). (a) Chemical... as Substituted ethoxylated hydrocarbon (PMN P-99-0313) is subject to reporting under this section...

  12. 40 CFR 721.4365 - Substituted ethoxylated hydrocarbon (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted ethoxylated hydrocarbon... Specific Chemical Substances § 721.4365 Substituted ethoxylated hydrocarbon (generic). (a) Chemical... as Substituted ethoxylated hydrocarbon (PMN P-99-0313) is subject to reporting under this section...

  13. 40 CFR 721.4365 - Substituted ethoxylated hydrocarbon (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted ethoxylated hydrocarbon... Specific Chemical Substances § 721.4365 Substituted ethoxylated hydrocarbon (generic). (a) Chemical... as Substituted ethoxylated hydrocarbon (PMN P-99-0313) is subject to reporting under this section...

  14. 40 CFR 721.3080 - Substituted phosphate ester (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phosphate ester (generic... Substances § 721.3080 Substituted phosphate ester (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted phosphate...

  15. 46 CFR 108.699 - Substitution of life preservers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Substitution of life preservers. 108.699 Section 108.699... AND EQUIPMENT Miscellaneous Equipment § 108.699 Substitution of life preservers. A work vest may not be substituted for a required life preserver— (a) For the life saving equipment requirements of...

  16. 46 CFR 108.699 - Substitution of life preservers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Substitution of life preservers. 108.699 Section 108.699... AND EQUIPMENT Miscellaneous Equipment § 108.699 Substitution of life preservers. A work vest may not be substituted for a required life preserver— (a) For the life saving equipment requirements of...

  17. 46 CFR 108.699 - Substitution of life preservers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Substitution of life preservers. 108.699 Section 108.699... AND EQUIPMENT Miscellaneous Equipment § 108.699 Substitution of life preservers. A work vest may not be substituted for a required life preserver— (a) For the life saving equipment requirements of...

  18. 17 CFR 10.32 - Substitution of parties.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Substitution of parties. 10.32... Parties and Limited Participation § 10.32 Substitution of parties. Upon motion and for good cause shown the Administrative Law Judge may order a substitution of parties....

  19. 76 FR 8666 - Substitution in Case of Death of Claimant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-15

    ... AFFAIRS 38 CFR Parts 3, 14, 20 RIN 2900-AN91 Substitution in Case of Death of Claimant AGENCY: Department... death of the claimant, request to be substituted for the claimant for the purposes of processing the... that they are submitted in response to ``RIN 2900-AN91--Substitution in Case of Death of...

  20. 40 CFR 721.843 - Substituted phenylazophenylazo phenol (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted phenylazophenylazo phenol... Specific Chemical Substances § 721.843 Substituted phenylazophenylazo phenol (generic). (a) Chemical... as substituted phenylazophenylazo, phenol (PMN P-00-0420) is subject to reporting under this...

  1. 40 CFR 721.843 - Substituted phenylazophenylazo phenol (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted phenylazophenylazo phenol... Specific Chemical Substances § 721.843 Substituted phenylazophenylazo phenol (generic). (a) Chemical... as substituted phenylazophenylazo, phenol (PMN P-00-0420) is subject to reporting under this...

  2. 40 CFR 721.10684 - Substituted benzenamine schiff base (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted benzenamine schiff base... Specific Chemical Substances § 721.10684 Substituted benzenamine schiff base (generic). (a) Chemical... as substituted benzenamine schiff base (PMN P-13-135) is subject to reporting under this section...

  3. 40 CFR 721.3764 - Fluorene substituted aromatic amine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fluorene substituted aromatic amine... Substances § 721.3764 Fluorene substituted aromatic amine. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a fluorene substituted...

  4. 40 CFR 721.3764 - Fluorene substituted aromatic amine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fluorene substituted aromatic amine... Substances § 721.3764 Fluorene substituted aromatic amine. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a fluorene substituted...

  5. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkyl substituted diaromatic... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  6. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkyl substituted diaromatic... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  7. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Alkyl substituted diaromatic... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  8. 40 CFR 721.575 - Substituted alkyl halide.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  9. 40 CFR 721.9572 - Substituted alkyl sulfonamide (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted alkyl sulfonamide (generic... Substances § 721.9572 Substituted alkyl sulfonamide (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  10. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkyl substituted diaromatic... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  11. 40 CFR 721.10087 - Substituted alkyl phosphine oxide (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted alkyl phosphine oxide... Specific Chemical Substances § 721.10087 Substituted alkyl phosphine oxide (generic). (a) Chemical... as substituted alkyl phosphine oxide (PMN P-06-332) is subject to reporting under this section...

  12. 40 CFR 721.10087 - Substituted alkyl phosphine oxide (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted alkyl phosphine oxide... Specific Chemical Substances § 721.10087 Substituted alkyl phosphine oxide (generic). (a) Chemical... as substituted alkyl phosphine oxide (PMN P-06-332) is subject to reporting under this section...

  13. 40 CFR 721.10087 - Substituted alkyl phosphine oxide (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkyl phosphine oxide... Specific Chemical Substances § 721.10087 Substituted alkyl phosphine oxide (generic). (a) Chemical... as substituted alkyl phosphine oxide (PMN P-06-332) is subject to reporting under this section...

  14. 40 CFR 721.575 - Substituted alkyl halide.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  15. 40 CFR 721.9572 - Substituted alkyl sulfonamide (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted alkyl sulfonamide (generic... Substances § 721.9572 Substituted alkyl sulfonamide (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  16. 40 CFR 721.10087 - Substituted alkyl phosphine oxide (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted alkyl phosphine oxide... Specific Chemical Substances § 721.10087 Substituted alkyl phosphine oxide (generic). (a) Chemical... as substituted alkyl phosphine oxide (PMN P-06-332) is subject to reporting under this section...

  17. 40 CFR 721.575 - Substituted alkyl halide.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  18. 40 CFR 721.9572 - Substituted alkyl sulfonamide (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkyl sulfonamide (generic... Substances § 721.9572 Substituted alkyl sulfonamide (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  19. 40 CFR 721.10087 - Substituted alkyl phosphine oxide (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted alkyl phosphine oxide... Specific Chemical Substances § 721.10087 Substituted alkyl phosphine oxide (generic). (a) Chemical... as substituted alkyl phosphine oxide (PMN P-06-332) is subject to reporting under this section...

  20. 40 CFR 721.9572 - Substituted alkyl sulfonamide (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted alkyl sulfonamide (generic... Substances § 721.9572 Substituted alkyl sulfonamide (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  1. 40 CFR 721.9572 - Substituted alkyl sulfonamide (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted alkyl sulfonamide (generic... Substances § 721.9572 Substituted alkyl sulfonamide (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  2. 40 CFR 721.840 - Alkyl substituted diaromatic hydrocarbons.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Alkyl substituted diaromatic... Specific Chemical Substances § 721.840 Alkyl substituted diaromatic hydrocarbons. (a) Chemical substance... alkyl substituted di-aro-matic hydrocarbons (PMN P-91-710) is subject to reporting under this...

  3. 40 CFR 721.575 - Substituted alkyl halide.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  4. 40 CFR 721.575 - Substituted alkyl halide.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted alkyl halide. 721.575... Substances § 721.575 Substituted alkyl halide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted alkyl halide (PMN P-83-1222)...

  5. 40 CFR 721.5965 - Substituted S-phenylthiazole (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted S-phenylthiazole (generic... Substances § 721.5965 Substituted S-phenylthiazole (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted...

  6. 40 CFR 721.1680 - Substituted benzoic acid (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted benzoic acid (generic... Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted benzoic acid (PMN...

  7. 40 CFR 721.5546 - Halogen substituted oxetanes (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Halogen substituted oxetanes (generic... Substances § 721.5546 Halogen substituted oxetanes (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogen substituted...

  8. 40 CFR 721.5546 - Halogen substituted oxetanes (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Halogen substituted oxetanes (generic... Substances § 721.5546 Halogen substituted oxetanes (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogen substituted...

  9. 40 CFR 721.5546 - Halogen substituted oxetanes (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Halogen substituted oxetanes (generic... Substances § 721.5546 Halogen substituted oxetanes (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogen substituted...

  10. 40 CFR 721.5546 - Halogen substituted oxetanes (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Halogen substituted oxetanes (generic... Substances § 721.5546 Halogen substituted oxetanes (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogen substituted...

  11. 40 CFR 721.5546 - Halogen substituted oxetanes (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Halogen substituted oxetanes (generic... Substances § 721.5546 Halogen substituted oxetanes (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as halogen substituted...

  12. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal...

  13. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal...

  14. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal...

  15. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal...

  16. 12 CFR 229.51 - General provisions governing substitute checks.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false General provisions governing substitute checks. 229.51 Section 229.51 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE... § 229.51 General provisions governing substitute checks. (a) Legal equivalence. A substitute check...

  17. 12 CFR 229.51 - General provisions governing substitute checks.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 3 2012-01-01 2012-01-01 false General provisions governing substitute checks. 229.51 Section 229.51 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE... § 229.51 General provisions governing substitute checks. (a) Legal equivalence. A substitute check...

  18. 12 CFR 229.51 - General provisions governing substitute checks.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false General provisions governing substitute checks. 229.51 Section 229.51 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE...) Substitute Checks § 229.51 General provisions governing substitute checks. (a) Legal equivalence....

  19. 12 CFR 229.51 - General provisions governing substitute checks.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 3 2014-01-01 2014-01-01 false General provisions governing substitute checks. 229.51 Section 229.51 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE...) Substitute Checks § 229.51 General provisions governing substitute checks. (a) Legal equivalence....

  20. Course Substitution Practices, Policies, and Implications for Students with Disabilities

    ERIC Educational Resources Information Center

    Forsbach-Rothman, Terri; Padro, Fernando F.; Rice-Mason, Jennifer

    2005-01-01

    Data from 65 colleges and universities across the United State were used to study course substitution practices for postsecondary students with disabilities. Data indicate that the majority of surveyed institutions (90.8%) allow course substitutions, yet only 50% had written policies directing substitution decisions. At responding institutions (N…

  1. 40 CFR 721.4594 - Substituted azo metal complex dye.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted azo metal complex dye. 721... Substances § 721.4594 Substituted azo metal complex dye. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted azo metal...

  2. 40 CFR 721.1680 - Substituted benzoic acid (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted benzoic acid (generic... Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted benzoic acid (PMN...

  3. 40 CFR 721.1680 - Substituted benzoic acid (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted benzoic acid (generic... Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted benzoic acid (PMN...

  4. 40 CFR 721.1680 - Substituted benzoic acid (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted benzoic acid (generic... Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted benzoic acid (PMN...

  5. 40 CFR 721.1680 - Substituted benzoic acid (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted benzoic acid (generic... Substances § 721.1680 Substituted benzoic acid (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted benzoic acid (PMN...

  6. 46 CFR 108.699 - Substitution of life preservers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Substitution of life preservers. 108.699 Section 108.699... AND EQUIPMENT Miscellaneous Equipment § 108.699 Substitution of life preservers. A work vest may not be substituted for a required life preserver— (a) For the life saving equipment requirements of...

  7. 46 CFR 108.699 - Substitution of life preservers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Substitution of life preservers. 108.699 Section 108.699... AND EQUIPMENT Miscellaneous Equipment § 108.699 Substitution of life preservers. A work vest may not be substituted for a required life preserver— (a) For the life saving equipment requirements of...

  8. 40 CFR 721.3080 - Substituted phosphate ester (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted phosphate ester (generic... Substances § 721.3080 Substituted phosphate ester (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted phosphate...

  9. 40 CFR 721.3080 - Substituted phosphate ester (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phosphate ester (generic... Substances § 721.3080 Substituted phosphate ester (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted phosphate...

  10. 40 CFR 721.3080 - Substituted phosphate ester (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phosphate ester (generic... Substances § 721.3080 Substituted phosphate ester (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted phosphate...

  11. 40 CFR 721.3080 - Substituted phosphate ester (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted phosphate ester (generic... Substances § 721.3080 Substituted phosphate ester (generic). (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted phosphate...

  12. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Haloalkyl substituted cyclic ethers... Substances § 721.3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  13. 40 CFR 721.3440 - Haloalkyl substituted cyclic ethers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Haloalkyl substituted cyclic ethers... Substances § 721.3440 Haloalkyl substituted cyclic ethers. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances haloalkyl substituted cyclic ethers (PMN P-85-368 and...

  14. 40 CFR 721.10043 - Dineopentyl-4-substituted phthalate (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Dineopentyl-4-substituted phthalate... Specific Chemical Substances § 721.10043 Dineopentyl-4-substituted phthalate (generic). (a) Chemical... as dineopentyl-4-substituted phthalate (PMN P-02-697) is subject to reporting under this section...

  15. 40 CFR 721.843 - Substituted phenylazophenylazo phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phenylazophenylazo phenol... Specific Chemical Substances § 721.843 Substituted phenylazophenylazo phenol (generic). (a) Chemical... as substituted phenylazophenylazo, phenol (PMN P-00-0420) is subject to reporting under this...

  16. 40 CFR 721.843 - Substituted phenylazophenylazo phenol (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted phenylazophenylazo phenol... Specific Chemical Substances § 721.843 Substituted phenylazophenylazo phenol (generic). (a) Chemical... as substituted phenylazophenylazo, phenol (PMN P-00-0420) is subject to reporting under this...

  17. 40 CFR 721.10384 - Substituted alkanolamine phenol (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted alkanolamine phenol... Specific Chemical Substances § 721.10384 Substituted alkanolamine phenol (generic). (a) Chemical substance... substituted alkanolamine phenol (PMN P-10-332) is subject to reporting under this section for the...

  18. 40 CFR 721.10508 - Alkene substituted Bis phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Alkene substituted Bis phenol (generic... Specific Chemical Substances § 721.10508 Alkene substituted Bis phenol (generic). (a) Chemical substance... alkene substituted bis phenol (PMN P-07-161) is subject to reporting under this section for...

  19. 40 CFR 721.10387 - Substituted bis-phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted bis-phenol (generic). 721... Substances § 721.10387 Substituted bis-phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted bis-phenol (PMN...

  20. 40 CFR 721.843 - Substituted phenylazophenylazo phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phenylazophenylazo phenol... Specific Chemical Substances § 721.843 Substituted phenylazophenylazo phenol (generic). (a) Chemical... as substituted phenylazophenylazo, phenol (PMN P-00-0420) is subject to reporting under this...

  1. 40 CFR 721.10386 - Substituted phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phenol (generic). 721... Substances § 721.10386 Substituted phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted phenol (PMN...

  2. 40 CFR 721.10387 - Substituted bis-phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted bis-phenol (generic). 721... Substances § 721.10387 Substituted bis-phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted bis-phenol (PMN...

  3. 40 CFR 721.10384 - Substituted alkanolamine phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted alkanolamine phenol... Specific Chemical Substances § 721.10384 Substituted alkanolamine phenol (generic). (a) Chemical substance... substituted alkanolamine phenol (PMN P-10-332) is subject to reporting under this section for the...

  4. 40 CFR 721.10384 - Substituted alkanolamine phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkanolamine phenol... Specific Chemical Substances § 721.10384 Substituted alkanolamine phenol (generic). (a) Chemical substance... substituted alkanolamine phenol (PMN P-10-332) is subject to reporting under this section for the...

  5. 40 CFR 721.10386 - Substituted phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phenol (generic). 721... Substances § 721.10386 Substituted phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted phenol (PMN...

  6. 40 CFR 721.10561 - Substituted phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted phenol (generic). 721... Substances § 721.10561 Substituted phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted phenol (PMN...

  7. 40 CFR 721.10561 - Substituted phenol (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted phenol (generic). 721... Substances § 721.10561 Substituted phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted phenol (PMN...

  8. 40 CFR 721.10386 - Substituted phenol (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted phenol (generic). 721... Substances § 721.10386 Substituted phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted phenol (PMN...

  9. 40 CFR 721.10508 - Alkene substituted Bis phenol (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Alkene substituted Bis phenol (generic... Specific Chemical Substances § 721.10508 Alkene substituted Bis phenol (generic). (a) Chemical substance... alkene substituted bis phenol (PMN P-07-161) is subject to reporting under this section for...

  10. 40 CFR 721.10387 - Substituted bis-phenol (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted bis-phenol (generic). 721... Substances § 721.10387 Substituted bis-phenol (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as substituted bis-phenol (PMN...

  11. 40 CFR 721.4258 - Substituted naphthalene hydrazide (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted naphthalene hydrazide... Specific Chemical Substances § 721.4258 Substituted naphthalene hydrazide (generic). (a) Chemical substance... substituted naphthalene hydrazide (PMN P-01-69) is subject to reporting under this section for the...

  12. 40 CFR 721.4258 - Substituted naphthalene hydrazide (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted naphthalene hydrazide... Specific Chemical Substances § 721.4258 Substituted naphthalene hydrazide (generic). (a) Chemical substance... substituted naphthalene hydrazide (PMN P-01-69) is subject to reporting under this section for the...

  13. 40 CFR 721.4258 - Substituted naphthalene hydrazide (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted naphthalene hydrazide... Specific Chemical Substances § 721.4258 Substituted naphthalene hydrazide (generic). (a) Chemical substance... substituted naphthalene hydrazide (PMN P-01-69) is subject to reporting under this section for the...

  14. 40 CFR 721.4258 - Substituted naphthalene hydrazide (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted naphthalene hydrazide... Specific Chemical Substances § 721.4258 Substituted naphthalene hydrazide (generic). (a) Chemical substance... substituted naphthalene hydrazide (PMN P-01-69) is subject to reporting under this section for the...

  15. 40 CFR 721.4258 - Substituted naphthalene hydrazide (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted naphthalene hydrazide... Specific Chemical Substances § 721.4258 Substituted naphthalene hydrazide (generic). (a) Chemical substance... substituted naphthalene hydrazide (PMN P-01-69) is subject to reporting under this section for the...

  16. 40 CFR 721.1747 - Substituted benzophenone (generic).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted benzophenone (generic... Substances § 721.1747 Substituted benzophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted benzophenone...

  17. 40 CFR 721.1747 - Substituted benzophenone (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted benzophenone (generic... Substances § 721.1747 Substituted benzophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted benzophenone...

  18. 40 CFR 721.1747 - Substituted benzophenone (generic).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted benzophenone (generic... Substances § 721.1747 Substituted benzophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted benzophenone...

  19. 40 CFR 721.1747 - Substituted benzophenone (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted benzophenone (generic... Substances § 721.1747 Substituted benzophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted benzophenone...

  20. 40 CFR 721.1747 - Substituted benzophenone (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted benzophenone (generic... Substances § 721.1747 Substituted benzophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted benzophenone...

  1. Substitute Addiction: A Concern for Researchers and Practitioners

    ERIC Educational Resources Information Center

    Sussman, Steve; Black, David S.

    2008-01-01

    An understanding of the role of substitute addictions remains unclear. This article examines the range and possible reward functions of substitute addictions. We suggest that prevention education and treatment need to take into account substitute addictions as an influential aspect of recovery. Research is needed to better understand the…

  2. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal...

  3. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal...

  4. 40 CFR 721.562 - Substituted alkylamine salt.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Substituted alkylamine salt. 721.562... Substances § 721.562 Substituted alkylamine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted alkylamine salt (PMN...

  5. 40 CFR 721.562 - Substituted alkylamine salt.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Substituted alkylamine salt. 721.562... Substances § 721.562 Substituted alkylamine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted alkylamine salt (PMN...

  6. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal...

  7. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal...

  8. 40 CFR 721.640 - Amine substituted metal salts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Amine substituted metal salts. 721.640... Substances § 721.640 Amine substituted metal salts. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substances identified generically as amine substituted metal...

  9. 40 CFR 721.562 - Substituted alkylamine salt.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted alkylamine salt. 721.562... Substances § 721.562 Substituted alkylamine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted alkylamine salt (PMN...

  10. 40 CFR 721.562 - Substituted alkylamine salt.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Substituted alkylamine salt. 721.562... Substances § 721.562 Substituted alkylamine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted alkylamine salt (PMN...

  11. 40 CFR 721.562 - Substituted alkylamine salt.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted alkylamine salt. 721.562... Substances § 721.562 Substituted alkylamine salt. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a substituted alkylamine salt (PMN...

  12. 49 CFR 383.77 - Substitute for driving skills tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 5 2010-10-01 2010-10-01 false Substitute for driving skills tests. 383.77... Substitute for driving skills tests. At the discretion of a State, the driving skill test as specified in... for a CDL, and substituted with either an applicant's driving record and previous passage of...

  13. 40 CFR 721.10708 - Zirconium substituted heteropolycyclic (generic).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Zirconium substituted heteropolycyclic... Specific Chemical Substances § 721.10708 Zirconium substituted heteropolycyclic (generic). (a) Chemical... as zirconium substituted heteropolycyclic (PMN P-13-152) is subject to reporting under this...

  14. 19 CFR 122.86 - Substitution of aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an...

  15. 19 CFR 122.86 - Substitution of aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an...

  16. 19 CFR 122.86 - Substitution of aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an...

  17. 19 CFR 122.86 - Substitution of aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an...

  18. 19 CFR 122.86 - Substitution of aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Substitution of aircraft. 122.86 Section 122.86... Substitution of aircraft. (a) Application. The residue cargo procedure applies when an airline must substitute aircraft to reach a destination due to weather conditions or operational factors which prevent an...

  19. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylamide-substituted epoxy. 721.320... Substances § 721.320 Acrylamide-substituted epoxy. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  20. 40 CFR 721.320 - Acrylamide-substituted epoxy.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Acrylamide-substituted epoxy. 721.320... Substances § 721.320 Acrylamide-substituted epoxy. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as acrylamide-substituted epoxy (PMN...

  1. [Substitution in psychogeriatrics. A comparative study in nursing homes and substitution projects in Drenthe].

    PubMed

    Schreurs, M

    1995-02-01

    Due to a strong increase of the ageing population in the Netherlands there is a growing need for care for psychogeriatric patients. The shortage of beds in psychogeriatric nursing homes has led to the development of substitute care in residential homes for the elderly and in community centers. If substitution is realized in these substitute care projects in the sense that alternative services are delivered for patients who would otherwise have been admitted to nursing homes, the level of impairment and disruptive behaviour should be of the same level in nursing homes and substitute care projects. Groups of patients of three nursing homes, three day-treatment facilities, eight day-care-projects in residential homes for the elderly and seven centers for day-care in the community were compared. Sociodemographic characteristics, behaviour and care-patterns of all 670 patients who were in care on the first of October of 1992 in these services were investigated. An assessment-scale for elderly patients, based on the Stockton Geriatric Rating Scale, was used to investigate behaviour. Substitute care appears to be possible for a limited and specific group of patients. Substitution for the severely disturbed patients (over 40% of the nursing home patients) does not seem to be possible. Due to the development of substitute care for psychogeriatric patients in residential homes for the elderly and centers for day-care in the community, services seem to develop towards more specific and specialized care. We recommend the foundation of a psychogeriatric case register, which allows the study of the transfer of patients across facilities.(ABSTRACT TRUNCATED AT 250 WORDS)

  2. Genomics and blood substitutes for 21st century Europe ("EuroBloodSubstitutes").

    PubMed

    Lowe, Kenneth C

    2006-01-01

    Blood transfusion is a medical intervention practised throughout the world. Blood is a biologically active material that can transmit diseases (e.g., HIV/AIDS and, perhaps, vCJD). People are becoming increasingly concerned about blood safety, despite improved screening and processing. Consequently, they are reluctant to donate blood or receive transfusions. Such problems can be solved by the development and incorporation into transfusion practices of so-called "blood substitutes" to replace some blood uses. The EuroBloodSubstitutes Project is funded by the European Union Framework 6 Programme to develop a technological platform for producing novel haem proteins and blood substitute components using micro-organisms (bacteria, fungi, yeast) as "cell factories." The Project will focus on bacteria (Escherichia coli), yeast (Pichia pastoris) and, longer-term, filamentous fungi (Aspergillus niger), all organisms used to synthesize commercially important products. The multi-centre Consortium consists of the Universities of (1) Nottingham (UK), (2) Essex (UK), (3) Denmark Technical (Denmark), (4) Lund (Sweden), (5) Milan (Italy), (6) Nancy (France), (7) Parma (Italy), (8) Rome "La Sapienza" (Italy), (9) Semmelweis (Hungary), together with (10) Alligator Bioscience, AB (Sweden), (11) LCC Engineering & Trading GmbH (Switzerland), (12) Scottish National Blood Transfusion Service (UK), and (13) Sanquin Bloodbank (The Netherlands). The EuroBloodSubstitutes Project will be informed by lay and professional stakeholders (e.g., clinicians, blood donors, patient groups, prescribers and policy makers). Outcomes of the Project are (1) the production of an information pack, decision aids and physician training aids, giving balanced overviews of the benefits and risks of transfusion of blood or potential substitutes, and (2) an interactive web site (http//:www.eurobloodsubstitutes.com) for information dissemination. This will improve knowledge and address misunderstandings about

  3. Cationic Gold Clusters Ligated with Differently Substituted Phosphines: Effect of Substitution on Ligand Reactivity and Binding

    SciTech Connect

    Johnson, Grant E.; Olivares, Astrid M.; Hill, David E.; Laskin, Julia

    2015-01-01

    We present a systematic study of the effect of the number of methyl (Me) and cyclohexyl (Cy) functional groups in monodentate phosphine ligands on the solution-phase synthesis of ligated sub-nanometer gold clusters and their gas-phase fragmentation pathways. Small mixed ligand cationic gold clusters were synthesized using ligand exchange reactions between pre-formed triphenylphosphine ligated (PPh3) gold clusters and monodentate Me- and Cy-substituted ligands in solution and characterized using electrospray ionization mass spectrometry (ESI-MS) and collision-induced dissociation (CID) experiments. Under the same experimental conditions, larger gold-PPh3 clusters undergo efficient exchange of unsubstituted PPh3 ligands for singly Me- and Cy-substituted PPh2Me and PPh2Cy ligands. The efficiency of ligand exchange decreases with an increasing number of Me or Cy groups in the substituted phosphine ligands. CID experiments performed for a series of ligand-exchanged gold clusters indicate that loss of a neutral Me-substituted ligand is preferred over loss of a neutral PPh¬3 ligand while the opposite trend is observed for Cy-substituted ligands. The branching ratio of the competing ligand loss channels is strongly correlated with the electron donating ability of the phosphorous lone pair as determined by the relative proton affinity of the ligand. The results indicate that the relative ligand binding energies increase in the order PMe3 < PPhMe2 < PPh2Me < PPh3< PPh2Cy < PPhCy2< PCy3. Furthermore, the difference in relative ligand binding energies increases with the number of substituted PPh3-mMem or PPh3-mCym ligands (L) exchanged onto each cluster. This study provides the first experimental determination of the relative binding energies of ligated gold clusters containing differently substituted monophosphine ligands, which are important to controlling their synthesis and reactivity in solution. The results also indicate that ligand substitution is an important

  4. Gas phase nitrosation of substituted benzenes

    NASA Astrophysics Data System (ADS)

    Dechamps, Noémie; Gerbaux, Pascal; Flammang, Robert; Bouchoux, Guy; Nam, Pham-Cam; Nguyen, Minh-Tho

    2004-03-01

    Using a combination of tandem mass spectrometric experiments (ion-molecule reactions, collisional activation, neutralization-reionization, MS/MS/MS) and theoretical calculations, protonated substituted benzenes are demonstrated to readily react with neutral t-butyl nitrite by the formation of stable complexes linking ionized nitric oxide to the benzene derivatives. The overall process is proposed to involve the concomitant elimination of neutral 2-methyl-2-propanol. Proton-bound dimers are proposed to intervene as the key-intermediates in these reactions, which also competitively produce protonated t-butyl nitrite. All the experiments were performed in a single hybrid tandem mass spectrometer of sector-quadrupole-sector configuration.

  5. Fluid vitreous substitutes in vitreo retinal surgery.

    PubMed

    Saxena, S; Gopal, L

    1996-12-01

    Advances in the surgical instrumentation and vitreoretinal techniques have allowed intraoperative reapproximation of retina to a more normal position. The use of intravitreally injected liquid materials (viscoelastic liquids, liquid perfluorocarbons and silicone oil), as adjunctive agents to vitreo-retinal surgery play an important role in facilitating retinal reattachment. These materials are used as intraoperative instruments to re-establish intraocular volume, assist in separating membranes adherent to the retina, manipulate retinal detachments and mechanically flatten detached retina. Over the longer term, silicone oil maintains intraocular tamponade. One should be cognizant of the potential uses, benefits and risks of each of these vitreous substitutes.

  6. Drop-in substitute for dichlorodifluoromethane refrigerant

    SciTech Connect

    Goble, G.H.

    1993-06-01

    A method for producing refrigeration in a refrigeration system designed for a dichlorodifluoromethane refrigerant is described, comprising drop-in substituting for said dichlorodifluoromethane a ternary mixture of about 2 to 20 weight percent isobutane, about 21 to 51 weight percent 1-chloro-1,1-difluoroethane, and about 41 to 71 weight percent chlorodifluoromethane, with the weight percentages of said components being weight percentages of the overall mixture; condensing said ternary mixture; and thereafter evaporating said ternary mixture in the vicinity of a body to be cooled.

  7. Stereoselective Formation of Fully Substituted Ketone Enolates.

    PubMed

    Haimov, Elvira; Nairoukh, Zackaria; Shterenberg, Alexander; Berkovitz, Tiran; Jamison, Timothy F; Marek, Ilan

    2016-04-25

    The application of stereochemically defined acyclic fully substituted enolates of ketones to the enantioselective synthesis of quaternary carbon stereocenters would be highly valuable. Herein, we describe an approach leading to the formation of several new stereogenic centers through a combined metalation-addition of a carbonyl-carbamoyl transfer to reveal in situ stereodefined α,α-disubstituted enolates of ketone as a single stereoisomer. This approach could produce a series of aldol and Mannich products from enol carbamate with excellent diastereomeric ratios. PMID:27027778

  8. [Generic and biosimilar drug substitution: a panacea?].

    PubMed

    Daly, M J; Guignard, B; Nendaz, M

    2015-10-14

    Drugs are the third largest source of expenditure under Switzerland's compulsory basic health insurance. Generics, the price of which should be at least 30 per cent less than the cost of the original drugs, can potentially allow substantial savings. Their approval requires bioequivalence studies and their use is safe, although some factors may influence patients' and physicians' acceptance. The increased substitution of biosimilar drugs for more expensive biotech drugs should allow further cost savings. In an attempt to extend the monopoly granted by the original drug patent, some pharmaceutical companies implement "evergreening" strategies including small modifications of the original substance for which the clinical benefit is not always demonstrated. PMID:26665661

  9. Generic substitution, financial interests, and imperfect agency.

    PubMed

    Rischatsch, Maurus; Trottmann, Maria; Zweifel, Peter

    2013-06-01

    Policy makers around the world seek to encourage generic substitution. In this paper, the importance of prescribing physicians' imperfect agency is tested using the fact that some Swiss jurisdictions allow physicians to dispense drugs on their own account (physician dispensing, PD) while others disallow it. We estimate a model of physician drug choice with the help of drug claim data, finding a significant positive association between PD and the use of generics. While this points to imperfect agency, generics are prescribed more often to patients with high copayments or low incomes.

  10. Constant-Elasticity-of-Substitution Simulation

    NASA Technical Reports Server (NTRS)

    Reiter, G.

    1986-01-01

    Program simulates constant elasticity-of-substitution (CES) production function. CES function used by economic analysts to examine production costs as well as uncertainties in production. User provides such input parameters as price of labor, price of capital, and dispersion levels. CES minimizes expected cost to produce capital-uncertainty pair. By varying capital-value input, one obtains series of capital-uncertainty pairs. Capital-uncertainty pairs then used to generate several cost curves. CES program menu driven and features specific print menu for examining selected output curves. Program written in BASIC for interactive execution and implemented on IBM PC-series computer.

  11. LEAD SUBSTITUTION AND ELIMINATION STUDY, PART II

    SciTech Connect

    T. MARTINEZ; M. COURNOYER

    2001-01-01

    Within the Nuclear Materials Technology Division of Los Alamos National Laboratory, lead is used as shielding for a variety of operations, including actinide chemistry, weapons production, radiochemistry, and analytical chemistry. In this study, waste minimization issues associated with replacing lead shielding with non-hazardous materials are addressed. These include institutional program available to support this effort, the hazards and accompanying controls grouped with lead shielding, operations that use lead bricks and how this effects the selection of the substitute. Life cycle management issues are also examined. As a final step, an approach to get buy-in from both technical and budget minded employees is presented.

  12. Acceptability of blood and blood substitutes.

    PubMed

    Ferguson, E; Prowse, C; Townsend, E; Spence, A; Hilten, J A van; Lowe, K

    2008-03-01

    Alternatives to donor blood have been developed in part to meet increasing demand. However, new biotechnologies are often associated with increased perceptions of risk and low acceptance. This paper reviews developments of alternatives and presents data, from a field-based experiment in the UK and Holland, on the risks and acceptance of donor blood and alternatives (chemical, genetically modified and bovine). UK groups perceived all substitutes as riskier than the Dutch. There is a negative association between perceived risk and acceptability. Solutions to increasing acceptance are discussed in terms of implicit attitudes, product naming and emotional responses.

  13. Stereoselective Formation of Fully Substituted Ketone Enolates.

    PubMed

    Haimov, Elvira; Nairoukh, Zackaria; Shterenberg, Alexander; Berkovitz, Tiran; Jamison, Timothy F; Marek, Ilan

    2016-04-25

    The application of stereochemically defined acyclic fully substituted enolates of ketones to the enantioselective synthesis of quaternary carbon stereocenters would be highly valuable. Herein, we describe an approach leading to the formation of several new stereogenic centers through a combined metalation-addition of a carbonyl-carbamoyl transfer to reveal in situ stereodefined α,α-disubstituted enolates of ketone as a single stereoisomer. This approach could produce a series of aldol and Mannich products from enol carbamate with excellent diastereomeric ratios.

  14. [Generic and biosimilar drug substitution: a panacea?].

    PubMed

    Daly, M J; Guignard, B; Nendaz, M

    2015-10-14

    Drugs are the third largest source of expenditure under Switzerland's compulsory basic health insurance. Generics, the price of which should be at least 30 per cent less than the cost of the original drugs, can potentially allow substantial savings. Their approval requires bioequivalence studies and their use is safe, although some factors may influence patients' and physicians' acceptance. The increased substitution of biosimilar drugs for more expensive biotech drugs should allow further cost savings. In an attempt to extend the monopoly granted by the original drug patent, some pharmaceutical companies implement "evergreening" strategies including small modifications of the original substance for which the clinical benefit is not always demonstrated.

  15. Interactions between light and vitreous fluid substitutes.

    PubMed

    Azzolini, C; Docchio, F; Brancato, R; Trabucchi, G

    1992-10-01

    To determine the interactions between light and vitreous fluid substitutes, we studied the absorption and fluorescence properties of the following fluids that are commonly used in vitreoretinal surgery: Ringer's solution, balanced salt citrate-buffered solution, balanced salt bicarbonate-buffered solution, hydroxypropyl methylcellulose ophthalmic solution, hyaluronate sodium, perfluorocarbons, silicone oil, and fluorosilicone oil. The absorption spectra for all the fluids peaked in the UV-C (reference range <280 nm) and UV-B (reference range from 315 to 280 nm) regions of the spectrum, with little or no absorption in the visible region of the spectrum (from 400 to 700 nm). Emission of almost all of the fluids occurred mainly in the 300- to 360-nm region, with fairly low-quantum efficiency. The limited light absorption properties of the fluids calls for caution during transpupillary and intraocular laser photocoagulation to avoid excessive retinal damage, mainly when the laser power is increased during treatment. Transmission of incoherent light (environmental and ophthalmic artificial light) through highly transparent vitreous fluid substitutes may lead in time to dangerous light exposure, particularly in aphakic eyes. The emitted fluorescence in these fluids generates a minimal risk of long-term damage.

  16. Chemical substitution in the undergraduate chemistry curriculum

    NASA Astrophysics Data System (ADS)

    Brook, Bryan David

    A recommended method for source reduction of pollutants is chemical substitution, in which hazardous materials are substituted for less hazardous materials. Here lab experiments and demonstrations were designed using household chemicals. The advantages include easy accessibility to low cost materials and minimal waste in comparison to traditional experiments. Students also showed more interest in performing experiments using familiar products. A Handbook of Household Chemicals was created. Using chemicals in the Handbook, qualitative and quantitative experiments are described that only require simple equipment. In addition, chemicals are identified in a quantitative analysis experiment with applications for upper level classes. Experiments requiring the use of water condensers were modified using an ice cooled condenser. The condenser, developed in our laboratory, is useful for distillation and reflux experiments where running water is not practical. Finally, demonstrations were designed for an overhead projector to be used in large classrooms. The experiments and demos can be used in any secondary school, college or university. The laboratory exercises can also accompany long distance learning and Internet chemistry courses. Several experiments using consumer products have been incorporated into the Pennsylvania Department of Education Science In Motion project. The program provides a van equipped with instruments and chemicals to be taken to local schools. Overall, the experiments discussed here provide a safe and low-cost alternative to traditional experiments.

  17. Coal to gas substitution using coal?!

    NASA Astrophysics Data System (ADS)

    Kempka, Thomas; Schlüter, Ralph

    2010-05-01

    Substitution of carbon-intensive coal with less carbon-intensive natural gas for energy production is discussed as one main pillar targeting reduction of antrophogenic greenhouse gas emissions by means of climate change mitigation. Other pillars are energy efficiency, renewable energies, carbon capture and storage as well as further development of nuclear energy. Taking into account innovative clean coal technologies such as UCG-CCS (underground coal gasification with carbon capture and storage), in which coal deposits are developed using directional drilling technologies and subsequently converted into a synthesis gas of high calorific value, the coupled conceptual approach can provide a synergetic technology for coal utilization and mitigation of carbon emissions. This study aims at the evaluation of UCǴ s carbon mitigation potentials and the review of the economical boundary conditions. The analytical models applied within this study are based on data available from world-wide UCG projects and extensive laboratory studies. In summary, scenarios considering costs and carbon storage potentials are economically feasible and thus competitive with less carbon-intensive energy generation technologies such as natural gas. Thus, coal to gas substitution can be one of the coal based options.

  18. Electronic Structure of Ethynyl Substituted Cyclobutadienes

    NASA Astrophysics Data System (ADS)

    Emmert, Frank Lee Emmert, III; Thompson, Stephanie J.; Slipchenko, Lyudmila V.

    2011-06-01

    We investigated the effects of ethynyl substitution on the electronic structure of cyclobutadiene. These species are involved in Bergman Cyclization reactionsand are possible intermediates in the formation of fullerenes and graphite sheets. Prediction of the electronic energy of cyclobutadiene is challenging for single-reference ab initio methods such as HF, MP2 or DFT because of Jahn-Teller distortions and the diradical character of the singlet state. We determined the vertical and adiabatic singlet-triplet energy splittings, the natural charges and spin densities in substituted cyclobutadienes, using the equations of motion spin flip coupled cluster with single and double excitations (EOM-SF-CCSD) method that accurately describes diradical states. The adiabatic singlet-triplet gaps decrease upon substituent addition, but the singlet state is always lower in energy. However, we found that the results are affected by spin-contamination of the reference state and deteriorate when an unrestricted HF reference is employed. O. L. Chapman, C. L. McIntosh, J. Pacansky, "Cyclobutadiene" J. Am. Chem. Soc. 1973, 95, (2), 614-617. N. S. Goroff, "Mechanism of Fullerene Formation." Acc. Chem. Res. 1996, 29, (2), 77-83. L.V. Slipchenko and A.I. Krylov, "Singlet-triplet gaps in diradicals by the Spin-Flip approach: A benchmark study", J. Chem. Phys. 2002, 117, 4694-4708.

  19. Pharmacology of Ativisha, Musta and their substitutes.

    PubMed

    Nagarajan, M; Kuruvilla, Gina R; Kumar, K Subrahmanya; Venkatasubramanian, Padma

    2015-01-01

    The Ayurvedic literature during the medieval period suggests the use of Musta (Cyperus rotundus), a common weed, as a pratinidhi dravya (substitute) for Ativisha (Aconitum heterophyllum), an endangered species. Contemporary Ayurvedic practice also uses Cryptocoryne spiralis, (known as Naattu Atividayam in South India) and Nagaramusta (Cyperus scariosus) as substitutes for Ativisha and Musta, respectively. This article reviews published literature on the pharmacology of the above four species. Both A. heterophyllum and C. rotundus are reported to possess antiinflammatory, antipyretic, antibacterial and antidiarrhoeal properties, while antiinflammatory and antibacterial activities are attributed to C. scariosus. No reports exist on the bioactivity of Cryptocoryne spiralis. It is interesting to note that other than the veerya which is different, the biological properties of Ativisha and Musta are similar according to Ayurvedic classification of dravyaguna. This is also supported by modern pharmacological studies, which show that, both A. heterophyllum and C. rotundus have antidiarrheal, antipyretic, antiinflammatory, antihyperlipidemic and hypoglycemic activities. However, the similarities between the discussed species cannot be attributed to their phytochemical composition or taxonomical classification as these are quite distinct. The dravyaguna method of classifying materials, which we are calling as "pharmaco-taxonomy", offers a unique way of classifying those plant materials which lack similarity at the botanical or chemical level, but are similar at the level of biological functions.

  20. Pharmacology of Ativisha, Musta and their substitutes

    PubMed Central

    Nagarajan, M.; Kuruvilla, Gina R.; Kumar, K. Subrahmanya; Venkatasubramanian, Padma

    2015-01-01

    The Ayurvedic literature during the medieval period suggests the use of Musta (Cyperus rotundus), a common weed, as a pratinidhi dravya (substitute) for Ativisha (Aconitum heterophyllum), an endangered species. Contemporary Ayurvedic practice also uses Cryptocoryne spiralis, (known as Naattu Atividayam in South India) and Nagaramusta (Cyperus scariosus) as substitutes for Ativisha and Musta, respectively. This article reviews published literature on the pharmacology of the above four species. Both A. heterophyllum and C. rotundus are reported to possess antiinflammatory, antipyretic, antibacterial and antidiarrhoeal properties, while antiinflammatory and antibacterial activities are attributed to C. scariosus. No reports exist on the bioactivity of Cryptocoryne spiralis. It is interesting to note that other than the veerya which is different, the biological properties of Ativisha and Musta are similar according to Ayurvedic classification of dravyaguna. This is also supported by modern pharmacological studies, which show that, both A. heterophyllum and C. rotundus have antidiarrheal, antipyretic, antiinflammatory, antihyperlipidemic and hypoglycemic activities. However, the similarities between the discussed species cannot be attributed to their phytochemical composition or taxonomical classification as these are quite distinct. The dravyaguna method of classifying materials, which we are calling as “pharmaco-taxonomy”, offers a unique way of classifying those plant materials which lack similarity at the botanical or chemical level, but are similar at the level of biological functions. PMID:26167002

  1. Pharmacology of Ativisha, Musta and their substitutes.

    PubMed

    Nagarajan, M; Kuruvilla, Gina R; Kumar, K Subrahmanya; Venkatasubramanian, Padma

    2015-01-01

    The Ayurvedic literature during the medieval period suggests the use of Musta (Cyperus rotundus), a common weed, as a pratinidhi dravya (substitute) for Ativisha (Aconitum heterophyllum), an endangered species. Contemporary Ayurvedic practice also uses Cryptocoryne spiralis, (known as Naattu Atividayam in South India) and Nagaramusta (Cyperus scariosus) as substitutes for Ativisha and Musta, respectively. This article reviews published literature on the pharmacology of the above four species. Both A. heterophyllum and C. rotundus are reported to possess antiinflammatory, antipyretic, antibacterial and antidiarrhoeal properties, while antiinflammatory and antibacterial activities are attributed to C. scariosus. No reports exist on the bioactivity of Cryptocoryne spiralis. It is interesting to note that other than the veerya which is different, the biological properties of Ativisha and Musta are similar according to Ayurvedic classification of dravyaguna. This is also supported by modern pharmacological studies, which show that, both A. heterophyllum and C. rotundus have antidiarrheal, antipyretic, antiinflammatory, antihyperlipidemic and hypoglycemic activities. However, the similarities between the discussed species cannot be attributed to their phytochemical composition or taxonomical classification as these are quite distinct. The dravyaguna method of classifying materials, which we are calling as "pharmaco-taxonomy", offers a unique way of classifying those plant materials which lack similarity at the botanical or chemical level, but are similar at the level of biological functions. PMID:26167002

  2. JROTC as a Substitute for PE: Really?

    PubMed Central

    Lounsbery, Monica A. F.; Holt, Kathryn A.; Monnat, Shannon A.; McKenzie, Thomas L.; Funk, Brian

    2014-01-01

    Purpose Even though physical education (PE) is an evidence-based strategy for providing and promoting physical activity, alternative programs such as Junior Reserve Officer Training Corps (JROTC) are commonly substituted for PE in many states. The purpose of this study was to compare student physical activity and lesson contexts during high school PE and JROTC sessions. Method SOFIT (System for Observing Fitness Instruction Time) was used to assess PE and JROTC sessions (N=38 each) in 4 high schools that provided both programs. Data were analyzed using t-tests, negative binomial regression, and logistic regression. Results Students engaged in significantly more moderate to vigorous physical activity during PE than JROTC sessions and they were significantly less sedentary. Significant differences between the two program types were also found among lesson contexts. Conclusions PE and JROTC provide substantially different content and contexts and students in them engage in substantially different amounts of moderate to vigorous physical activity. Students in JROTC, and perhaps other alternative programs, are less likely to accrue health-supporting physical activity and engage in fewer opportunities to be physically fit and motorically skilled. Policies and practices for providing substitutions for PE should be carefully examined. PMID:25141093

  3. Sugar substitutes: Health controversy over perceived benefits

    PubMed Central

    Tandel, Kirtida R.

    2011-01-01

    Sugar is an inseparable part of the food we consume. But too much sugar is not ideal for our teeth and waistline. There have been some controversial suggestions that excessive sugar may play an important role in certain degenerative diseases. So artificial sweeteners or artificially sweetened products continue to attract consumers. A sugar substitute (artificial sweetener) is a food additive that duplicates the effect of sugar in taste, but usually has less food energy. Besides its benefits, animal studies have convincingly proven that artificial sweeteners cause weight gain, brain tumors, bladder cancer and many other health hazards. Some kind of health related side effects including carcinogenicity are also noted in humans. A large number of studies have been carried out on these substances with conclusions ranging from “safe under all conditions” to “unsafe at any dose”. Scientists are divided in their views on the issue of artificial sweetener safety. In scientific as well as in lay publications, supporting studies are often widely referenced while the opposing results are de-emphasized or dismissed. So this review aims to explore the health controversy over perceived benefits of sugar substitutes. PMID:22025850

  4. Sugar substitutes: Health controversy over perceived benefits.

    PubMed

    Tandel, Kirtida R

    2011-10-01

    Sugar is an inseparable part of the food we consume. But too much sugar is not ideal for our teeth and waistline. There have been some controversial suggestions that excessive sugar may play an important role in certain degenerative diseases. So artificial sweeteners or artificially sweetened products continue to attract consumers. A sugar substitute (artificial sweetener) is a food additive that duplicates the effect of sugar in taste, but usually has less food energy. Besides its benefits, animal studies have convincingly proven that artificial sweeteners cause weight gain, brain tumors, bladder cancer and many other health hazards. Some kind of health related side effects including carcinogenicity are also noted in humans. A large number of studies have been carried out on these substances with conclusions ranging from "safe under all conditions" to "unsafe at any dose". Scientists are divided in their views on the issue of artificial sweetener safety. In scientific as well as in lay publications, supporting studies are often widely referenced while the opposing results are de-emphasized or dismissed. So this review aims to explore the health controversy over perceived benefits of sugar substitutes.

  5. Muon-Substituted Malonaldehyde: Transforming a Transition State into a Stable Structure by Isotope Substitution.

    PubMed

    Goli, Mohammad; Shahbazian, Shant

    2016-02-12

    Isotope substitutions are usually conceived to play a marginal role on the structure and bonding pattern of molecules. However, a recent study [Angew. Chem. Int. Ed. 2014, 53, 13706-13709; Angew. Chem. 2014, 126, 13925-13929] further demonstrates that upon replacing a proton with a positively charged muon, as the lightest radioisotope of hydrogen, radical changes in the nature of the structure and bonding of certain species may take place. The present report is a primary attempt to introduce another example of structural transformation on the basis of the malonaldehyde system. Accordingly, upon replacing the proton between the two oxygen atoms of malonaldehyde with the positively charged muon a serious structural transformation is observed. By using the ab initio nuclear-electronic orbital non-Born-Oppenheimer procedure, the nuclear configuration of the muon-substituted species is derived. The resulting nuclear configuration is much more similar to the transition state of the proton transfer in malonaldehyde rather than to the stable configuration of malonaldehyde. The comparison of the "atoms in molecules" (AIM) structure of the muon-substituted malonaldehyde and the AIM structure of the stable and the transition-state configurations of malonaldehyde also unequivocally demonstrates substantial similarities of the muon-substituted malonaldehyde to the transition state. PMID:26749489

  6. Muon-Substituted Malonaldehyde: Transforming a Transition State into a Stable Structure by Isotope Substitution.

    PubMed

    Goli, Mohammad; Shahbazian, Shant

    2016-02-12

    Isotope substitutions are usually conceived to play a marginal role on the structure and bonding pattern of molecules. However, a recent study [Angew. Chem. Int. Ed. 2014, 53, 13706-13709; Angew. Chem. 2014, 126, 13925-13929] further demonstrates that upon replacing a proton with a positively charged muon, as the lightest radioisotope of hydrogen, radical changes in the nature of the structure and bonding of certain species may take place. The present report is a primary attempt to introduce another example of structural transformation on the basis of the malonaldehyde system. Accordingly, upon replacing the proton between the two oxygen atoms of malonaldehyde with the positively charged muon a serious structural transformation is observed. By using the ab initio nuclear-electronic orbital non-Born-Oppenheimer procedure, the nuclear configuration of the muon-substituted species is derived. The resulting nuclear configuration is much more similar to the transition state of the proton transfer in malonaldehyde rather than to the stable configuration of malonaldehyde. The comparison of the "atoms in molecules" (AIM) structure of the muon-substituted malonaldehyde and the AIM structure of the stable and the transition-state configurations of malonaldehyde also unequivocally demonstrates substantial similarities of the muon-substituted malonaldehyde to the transition state.

  7. Sucrose substitutes and their role in caries prevention.

    PubMed

    Matsukubo, Takashi; Takazoe, Ichiro

    2006-06-01

    Many non- or low-cariogenic sucrose substitutes are currently available and are found as ingredients of a variety of candy, chewing gum, and drinks. Recently the role of sugar alcohols in promoting remineralisation of enamel has attracted much attention. Thus, the dental profession needs to understand the general characteristics and features of sugar substitutes to provide advice on oral health to patients as well as the general public. There are two critical requirements for sucrose substitutes, namely, being nutritionally appropriate and not being detrimental to the overall general health of the individual. The use of a greater variety of confectionary containing sucrose substitutes and the development of new substitutes with high nutritional value are essential in the battle against caries. In this paper we review in detail the characteristics of sucrose substitutes currently in use, their role in caries prevention and promotion of oral health.

  8. Design, Syntheses, and Biological Evaluation of 14-Heteroaromatic Substituted Naltrexone Derivatives: Pharmacological Profile Switch from Mu Opioid Receptor Selectivity to Mu/Kappa Opioid Receptor Dual Selectivity

    PubMed Central

    Yuan, Yunyun; Zaidi, Saheem A.; Elbegdorj, Orgil; Aschenbach, Lindsey C. K.; Li, Guo; Stevens, David L.; Scoggins, Krista L.; Dewey, William L.; Selley, Dana E.; Zhang, Yan

    2015-01-01

    Based on a mu opioid receptor (MOR) homology model and the “isosterism” concept, three generations of 14-heteroaromatically substituted naltrexone derivatives were designed, synthesized, and evaluated as potential MOR selective ligands. The first generation ligands appeared to be MOR selective, whereas the second and the third generation ones showed MOR/kappa opioid receptor (KOR) dual selectivity. Docking of ligands 2 (MOR selective) and 10 (MOR/KOR dual selective) to the three opioid receptor crystal structures revealed a non-conserved residue facilitated “hydrogen bonding network” that could be responsible for their distinctive selectivity profiles. The MOR/KOR dual selective ligand 10 showed no agonism and acted as a potent antagonist in the tail flick assay. It also produced less severe opioid withdrawal symptoms than naloxone in morphine dependent mice. In conclusion, ligand 10 may serve as a novel lead compound to develop MOR/KOR dual selective ligands, which might possess unique therapeutic value for opioid addiction treatment. PMID:24144240

  9. Towards the development of hemerythrin-based blood substitutes.

    PubMed

    Mot, Augustin C; Roman, Alina; Lupan, Iulia; Kurtz, Donald M; Silaghi-Dumitrescu, Radu

    2010-08-01

    Hemerythrin is proposed as an alternative to hemoglobin-based blood substitutes. In contrast to hemoglobin, hemerythrin exhibits negligible reactivity towards oxidative and nitrosative stress agents (peroxide, nitric oxide, nitrite). Protocols for attachment of polyethylene glycol and glutaraldehyde cross-linking of Hr are described. These derivatizations appear to have favorable effects on O(2) affinity and autoxidation rates for use in blood substitutes. Based on lessons learned from hemoglobin-based blood substitutes, these derivatizations should also help limit extravasation and antigenicity of a hemerythrin-based blood substitute.

  10. Substitutions between Water and other Agricultural Inputs - An Empirical Analysis

    NASA Astrophysics Data System (ADS)

    Cai, X.; You, J.

    2005-12-01

    Increasing concerns about water availability, environmental water requirement and water quality have led to an increased importance of quantitative assessments of the substitution between water and other agricultural inputs at the margin for agricultural and environmental policy analysis. This paper explores the potential substitutions between water and other agricultural inputs in irrigated agriculture through an empirical study. The study include (1) an analysis based on a crop production function for net substitution at the crop field and farm levels; and (2) a numerical study for gross substitution in the context of water allocation in river basins thorough an integrated hydrologic-economic river basin model. Along with the empirical analysis and numerical illustrations, we discuss several theoretical issues relevant to substitutions between water and other inputs, such as (1) selection of indicators of elasticity of substitution, depending on farmers' concerns on yield, production, or profit; (2) appropriateness of net or gross substitution analysis, which is relevant to the spatial scale of the analysis (field, district or region), as well as farmers' concerns; and (3) output impact of substitutions. Water is both a natural resource and an economic input, and the constraints on water include those from both physical and socio-economic aspects. Therefore, the output impact of the substitution between water and other inputs should be extended from a pure economic concept to the context of integrated hydrologic-economic systems.

  11. Substitute consent in women with psychosis.

    PubMed

    Seeman, Mary V

    2014-11-01

    When treating patients with schizophrenia, substitute consent for treatment is often needed because of the patient's decisional incapacity. The goal of this article is to illustrate the potential problems involved in surrogate decision-making in a mental health service for women. A composite case vignette that highlights these issues is presented. The vignette was developed based on files from a women's clinic for psychosis and a selective literature review. The quality of the relationship between marriage partners and the possibility of pregnancy, motherhood, and child custody disputes all complicate the ethics of next- of-kin surrogate decision-making. The concept of "best interests" (the mother's or the child's) is not straightforward. A related ethical issue is whether/when to disclose psychiatric information to spouses. It is hoped that this paper will engender further discussion in medicine, cultural studies, ethics, and the law. PMID:25406056

  12. Sucrose and sucrose substitutes. Industrial considerations.

    PubMed

    Mackay, D A

    1978-01-01

    The problem of reducing the sugar content of sugary foods is presented from the food manufacturer's point of view. The distinction is made between the need for artificial sweeteners and the more pressing need for bulking agents with at least some of the technological properties of sugar. In view of the considerable sales success of sugarless confections, accounting for over an estimated 30,000,000 lbs. of sorbitol per annum, the clouded prospect for more general sugar substitution in other food categories is discussed with especial reference to the consequent problems in product claims and nomenclature, and the enormous expense of proving safety and dental claims. Finally, an overview of the competitive consumer and regulatory pressures is given, with an urgent appeal to the dental profession to take the initiative for guiding the food processor to dentally improved foods.

  13. Nanobiotechnology for hemoglobin-based blood substitutes.

    PubMed

    Chang, T M S

    2009-04-01

    Nanobiotechnology is the assembling of biological molecules into nanodimension complexes. This has been used for the preparation of polyhemoglobin formed by the assembling of hemoglobin molecules into a soluble nanodimension complex. New generations of this approach include the nanobiotechnological assembly of hemoglobin, catalase, and superoxide dismutase into a soluble nanodimension complex. This acts as an oxygen carrier and an antioxidant for those conditions with potential for ischemiareperfusion injuries. Another recent novel approach is the assembling of hemoglobin and fibrinogen into a soluble nanodimension polyhemoglobin-fibrinogen complex that acts as an oxygen carrier with platelet-like activity. This is potentially useful in cases of extensive blood loss requiring massive replacement using blood substitutes, resulting in the need for the replacement of platelets and clotting factors. A further step is the preparation of nanodimension artificial red blood cells that contain hemoglobin and all the enzymes present in red blood cells.

  14. Hazardous Solvent Substitution Data System tutorial

    SciTech Connect

    Twitchell, K.E.; Skinner, N.L.

    1993-07-01

    This manual is the tutorial for the Hazardous Solvent Substitution Data System (HSSDS), an online, comprehensive system of information on alternatives to hazardous solvents and related subjects. The HSSDS data base contains product information, material safety data sheets, toxicity reports, usage reports, biodegradable data, product chemical element lists, and background information on solvents. HSSDS use TOPIC{reg_sign} to search for information based on a query defined by the user. TOPIC provides a full text retrieval of unstructured source documents. In this tutorial, a series of lessons is provided that guides the user through basic steps common to most queries performed with HSSDS. Instructions are provided for both window-based and character-based applications.

  15. High pressure chemistry of substituted acetylenes

    SciTech Connect

    Chellappa, Raja; Dattelbaum, Dana; Sheffield, Stephen; Robbins, David

    2011-01-25

    High pressure in situ synchrotron x-ray diffraction experiments were performed on substituted polyacetylenes: tert-butyl acetylene [TBA: (CH{sub 3}){sub 3}-C{triple_bond}CH] and ethynyl trimethylsilane [ETMS: (CH{sub 3}){sub 3}-Si{triple_bond}CH] to investigate pressure-induced chemical reactions. The starting samples were the low temperature crystalline phases which persisted metastably at room temperature and polymerized beyond 11 GPa and 26 GPa for TBA and ETMS respectively. These reaction onset pressures are considerably higher than what we observed in the shockwave studies (6.1 GPa for TBA and 6.6 GPa for ETMS). Interestingly, in the case of ETMS, it was observed with fluid ETMS as starting sample, reacts to form a semi-crystalline polymer (crystalline domains corresponding to the low-T phase) at pressures less than {approx}2 GPa. Further characterization using vibrational spectroscopy is in progress.

  16. Elf Atochem boosts production of CFC substitutes

    SciTech Connect

    Not Available

    1992-05-01

    To carve out a larger share of the market for acceptable chlorofluorocarbon substitutes, Elf Atochem (Paris) is expanding its production of HFC-134a, HCFC-141b and HCFC-142b in the U.S. and in France. This paper reports that the company is putting the finishing touches on a plant at its Pierre-Benite (France) facility, to bring 9,000 m.t./yr (19.8 million lb) of HFC-134a capacity on-line by September. Construction is scheduled to begin next year at the company's Calvert City, Ky., plant, where a 15,000-m.t./yr (33-million-lb) unit for HFC-134a will come onstream by 1995.

  17. Non-conservation of Carter in black hole spacetimes

    NASA Astrophysics Data System (ADS)

    Grant, Alexander; Flanagan, Éanna É.

    2015-08-01

    Freely falling point particles in the vicinity of Kerr black holes are subject to a conservation law, that of their Carter constant. We consider the conjecture that this conservation law is a special case of a more general conservation law, valid for arbitrary processes obeying local energy momentum conservation. Under some fairly general assumptions we prove that the conjecture is false: there is no conservation law for conserved stress-energy tensors on the Kerr background that reduces to conservation of Carter for a single point particle.

  18. Scalar dissipation rates in non-conservative transport systems

    PubMed Central

    Engdahl, Nicholas B.; Ginn, Timothy R.; Fogg, Graham E.

    2014-01-01

    This work considers how the inferred mixing state of diffusive and advective-diffusive systems will vary over time when the solute masses are not constant over time. We develop a number of tools that allow the scalar dissipation rate to be used as a mixing measure in these systems without calculating local concentration gradients. The behavior of dissipation rates are investigated for single and multi-component kinetic reactions and a commonly studied equilibrium reaction. The scalar dissipation rate of a tracer experiencing first order decay can be determined exactly from the decay constant and the dissipation rate of a passive tracer, and the mixing rate of a conservative component is not the superposition of the solute specific mixing rates. We then show how the behavior of the scalar dissipation rate can be determined from a limited subset of an infinite domain. Corrections are derived for constant and time dependent limits of integration the latter is used to approximate dissipation rates in advective-diffusive systems. Several of the corrections exhibit similarities to the previous work on mixing, including non-Fickian mixing. This illustrates the importance of accounting for the effects that reaction systems or limited monitoring areas may have on the inferred mixing state. PMID:23584457

  19. Identification of a cys-ser substitution in the 5-HT{sub 2C} (HTR2C) receptor gene and allelic association to violent behavior and alcoholism

    SciTech Connect

    Lappalainen, J.; Ozaki, N.; Goldman, D.

    1994-09-01

    Several lines of evidence suggest that brain serotonergic functions, including behavioral and neurochemical responses to 5-HT{sub 2C} agonist, are abnormal in some individuals with alcoholism and aggressive behaviors. The aim of the present study was to identify coding sequence variants in the human 5-HT{sub 2C} receptor gene which may cause abnormal or variant function of this receptor. Using SSCP analysis, a non-conservative cys-ser substitution was found in the 5-HT{sub 2C} receptor (designated 5-HT{sub 2Ccys} and 5-HT{sub 2Cser}). The polymorphism was typed in CEPH families to genetically map the gene. To test for association of the variant to alcoholism, violent behavior and serotonin function, the 5-HT{sub 2C} genotypes of 151 non-related Finnish male alcoholic violent offenders and impulsive fire setters and 127 Finnish psychiatrically interviewed healthy male volunteers were determined. CSF 5-HIAA concentrations were available for 74 alcoholic violent offenders and 25 healthy volunteers. Linkage analysis placed the 5-HT{sub 2C} gene on Xq21, a region that has been previously shown to contain genes for several mental retardation syndromes. The 5-HT{sub 2Ccys}/5-HT{sub 2Cser} genotype frequencies in alcoholic violent offenders and controls differed significantly (0.90/0.10 and 0.82/0.18, respectively, P=0.048). The association was found to be strongest in the violent offenders who did not fulfill the criteria for antisocial personality disorder (5-HT{sub 2Ccys}/5-HT{sub 2Cser} 0.93/0.07, p=0.021). No association was found between CSF 5-HIAA concentrations and 5-HT{sub 2C} genotype. These results implicate a 5-HT{sub 2C} receptor amino acid substitution in predisposition to alcohol abuse and violent behavior in a subgroup of alcoholics.

  20. 31 CFR 240.3 - Electronic checks and substitute checks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 2 2011-07-01 2011-07-01 false Electronic checks and substitute... OF CHECKS DRAWN ON THE UNITED STATES TREASURY General Provisions § 240.3 Electronic checks and substitute checks. (a) Legal equivalence of electronic checks. An electronic check for which a...

  1. 40 CFR 721.1738 - Substituted benzotriazole (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted benzotriazole (generic name). 721.1738 Section 721.1738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.1738 Substituted benzotriazole (generic name). (a) Chemical...

  2. 40 CFR 721.1700 - Halonitrobenzoic acid, substituted (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Halonitrobenzoic acid, substituted (generic name). 721.1700 Section 721.1700 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1700 Halonitrobenzoic acid, substituted (generic name). (a)...

  3. 40 CFR 721.1738 - Substituted benzotriazole (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted benzotriazole (generic name). 721.1738 Section 721.1738 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.1738 Substituted benzotriazole (generic name). (a) Chemical...

  4. 40 CFR 721.2527 - Substituted diphenylazo dye (generic name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Substituted diphenylazo dye (generic name). 721.2527 Section 721.2527 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.2527 Substituted diphenylazo dye (generic name). (a) Chemical...

  5. 40 CFR 721.2527 - Substituted diphenylazo dye (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Substituted diphenylazo dye (generic name). 721.2527 Section 721.2527 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.2527 Substituted diphenylazo dye (generic name). (a) Chemical...

  6. 40 CFR 721.1700 - Halonitrobenzoic acid, substituted (generic name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Halonitrobenzoic acid, substituted (generic name). 721.1700 Section 721.1700 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Specific Chemical Substances § 721.1700 Halonitrobenzoic acid, substituted (generic name). (a)...

  7. 36 CFR 223.189 - Prohibitions against substitution.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Relief Act of 1990 Program § 223.189 Prohibitions against substitution. (a) Direct substitution... Section 490(a) of the Act (16 U.S.C. 620b), an exemption to the prohibition in § 223.189(a)(1)(B) of this... Act of 1990 (16 U.S.C. 620, et seq.). The prohibition in this paragraph does not apply to...

  8. 46 CFR 502.43 - Substitution of parties.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 9 2010-10-01 2010-10-01 false Substitution of parties. 502.43 Section 502.43 Shipping FEDERAL MARITIME COMMISSION GENERAL AND ADMINISTRATIVE PROVISIONS RULES OF PRACTICE AND PROCEDURE Parties § 502.43 Substitution of parties. In appropriate circumstances, the Commission or presiding officer...

  9. Nucleophilic substitution reaction for post-functionalization of polyoxometalates

    SciTech Connect

    Yin, Panchao; Li, Qiang; Zhang, Jin; Wang, Longsheng; Hao, Jian; Wei, Yongge

    2015-07-06

    In this study, a hexamolybdate-based organic inorganic hybrid molecule containing a chloralkane fragment is synthesized and its Cl atom can be substituted by iodine and nitrate through nucleophilic substitution reactions in high yields, which provide a post-functionalization protocol to bring in various additional functional groups into polyoxometalate-based hybrid materials under mild conditions.

  10. 12 CFR 229.53 - Substitute check indemnity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Substitute check indemnity. 229.53 Section 229.53 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC) Substitute Checks §...

  11. 12 CFR 229.52 - Substitute check warranties.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Substitute check warranties. 229.52 Section 229.52 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC) Substitute Checks §...

  12. 12 CFR 229.51 - General provisions governing substitute checks.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false General provisions governing substitute checks. 229.51 Section 229.51 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC) Substitute...

  13. 76 FR 39062 - Substitution in Case of Death of Claimant

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ... proposed rule, ``Substitution in Case of Death of Claimant'' (76 FR 8666), published in the Federal... Case of Death of Claimant'' (76 FR 8666), published in the Federal Register on February 15, 2011, in... AFFAIRS 38 CFR Parts 3, 14, and 20 RIN 2900-AN91 Substitution in Case of Death of Claimant...

  14. 16 CFR 301.35 - Substitution of labels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.35 Substitution of labels. (a) Persons authorized under the provisions of section 3(e) of the act to substitute labels affixed to fur... said fur product for record purposes is inserted thereon without interfering with or obscuring in...

  15. 16 CFR 301.35 - Substitution of labels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.35 Substitution of labels. (a) Persons authorized under the provisions of section 3(e) of the act to substitute labels affixed to fur... said fur product for record purposes is inserted thereon without interfering with or obscuring in...

  16. 16 CFR 301.35 - Substitution of labels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.35 Substitution of labels. (a) Persons authorized under the provisions of section 3(e) of the act to substitute labels affixed to fur... said fur product for record purposes is inserted thereon without interfering with or obscuring in...

  17. 16 CFR 301.35 - Substitution of labels.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.35 Substitution of labels. (a) Persons authorized under the provisions of section 3(e) of the act to substitute labels affixed to fur... said fur product for record purposes is inserted thereon without interfering with or obscuring in...

  18. 16 CFR 301.35 - Substitution of labels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AND REGULATIONS UNDER FUR PRODUCTS LABELING ACT Regulations § 301.35 Substitution of labels. (a) Persons authorized under the provisions of section 3(e) of the act to substitute labels affixed to fur... said fur product for record purposes is inserted thereon without interfering with or obscuring in...

  19. The role of carbon fibre as a flexor tendon substitute.

    PubMed

    Rawlins, R

    1983-06-01

    Experiments have been carried out on Rhesus monkeys to determine the effectiveness of carbon fibre as a flexor tendon substitute. Though the strength, flexibility and capacity to induce a neotendon make carbon fibre an ideal flexor tendon substitute, induction of fibrosis and accompanying increase in bulk of the implant resulted in failure.

  20. [Innovative wound therapy and skin substitutes for burns].

    PubMed

    Vogt, P M; Kolokythas, P; Niederbichler, A; Knobloch, K; Reimers, K; Choi, C Y

    2007-04-01

    The success of modern burn therapy is based mainly on special burn intensive care, topical treatment, early eschar excision, and wound closure by immediate skin grafting or skin substitutes. This paper describes the current state of wound care and skin substitutes in burn therapy.