39,020 research outputs found
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Investigation of structural changes of ortho- and para-cortical cells in bleached human hair by Differential Scanning Calorimetry
No full textInvestigation of structural changes of Ortho- and Para- Cortical cells in bleached human hair by Differential Scanning CalorimetryD. Zhang 1, F. J. Wortmann 1, G. Wortmann 1, E. Schulze zur Wiesche 2 1 School of Materials, University of Manchester, Manchester, UK1 TRI Princeton, NJ, USA2 Henkel AG &Co KGaA, Hamburg, GERAbstract: Using three Gaussian distributions, the deconvoluted DSC results for two bleached hair samples confirm that a stronger bleach causes a homogenous structural damage on both para- and ortho-cortex with prolonged bleaching time. The predominant structural damage for various heating rates is verified to only occur in the IF. α-helices in three cortical components are homogenously damaged on chemically damaged fibres. However, heating rates yield a homogenous effect on disulfide linkages of para- and ortho- cortex, regardless of any previous oxidation treatment. Key Words: Deconvolution, para-cortex, ortho-cortex, heating rates, bleachin
Investigation of structural changes of ortho- and para-cortical cells in bleached human hair by Differential Scanning Calorimetry
No full textInvestigation of structural changes of Ortho- and Para- Cortical cells in bleached human hair by Differential Scanning CalorimetryD. Zhang 1, F. J. Wortmann 1, G. Wortmann 1, E. Schulze zur Wiesche 2 1 School of Materials, University of Manchester, Manchester, UK1 TRI Princeton, NJ, USA2 Henkel AG &Co KGaA, Hamburg, GERAbstract: Using three Gaussian distributions, the deconvoluted DSC results for two bleached hair samples confirm that a stronger bleach causes a homogenous structural damage on both para- and ortho-cortex with prolonged bleaching time. The predominant structural damage for various heating rates is verified to only occur in the IF. α-helices in three cortical components are homogenously damaged on chemically damaged fibres. However, heating rates yield a homogenous effect on disulfide linkages of para- and ortho- cortex, regardless of any previous oxidation treatment. Key Words: Deconvolution, para-cortex, ortho-cortex, heating rates, bleachin
Thermal analysis and synergistic tools for the development of a semi-permanent hair straightening technology
No full textThis research was carried out with the objective to develop a thermal analysis protocol into a method of damage assessment and claims support for a new semi-permanent hair straightening technology. The investigation determined the effects of the treatment on hair fibre composition and properties using Modulated Differential Scanning Calorimetry (MDSC) [1], Fourier Transform Infrared Spectroscopy (FTIR) [2], Gel Electrophoresis (SDS-PAGE) [3] and curl retention tests [4]. The effects of the new cysteamine treatment are compared with effects of a standard thioglycolate treatment and the daily use of straightening irons. Virgin, Caucasian hair was treated once with each chemical treatment and washed every day for 84 days. In a parallel study, hair was washed and straightened repeatedly using a standardised protocol at 190oC for 84 days. Samples were taken after 2, 28, 56 and 84 days for analysis by MDSC in water, ATR- and Trans-FTIR. Separate samples were treated once and subjected to curl retention tests and protein analysis. DSC measurements in water yield the keratin denaturation enthalpy (ΔHD), which relates to the thermal stability of the keratin intermediate filaments (KIFs), and the denaturation temperature (TD), which relates to the properties of the keratin associated-proteins (KAPs). The results show that chemical and thermal straightening cause a reduction in α-helix content and matrix viscosity. FTIR measurements give information on the formation of cysteic acid in the cuticle cells and the cortex. ATR-FTIR showed that the cysteamine–based treatment produces less cysteic acid in the cuticle layers than the standard treatment. Curl retention and SDS-PAGE were used to show the variability in the efficacy of the cysteamine treatment related to the heterogeneity of human hair. The results from both tests show that an individual’s hair will react with the product to a different extent, depending on the extractability of the keratin protein groups.In conclusion, we deduce that all straightening techniques, chemical and thermal, have a pronounced effect on the structural and chemical properties of hair fibres. These effects can be used to further develop and optimize this and related products. DSC has been shown to be an integral synergistic technique for the investigation of changes to hair morphology.This research was supported by the UK Technology Strategy Board under the Knowledge Transfer Partnership scheme.Cyril Keattch Award, Thermal Methods Group, Royal Society of Chemistry, 2014.[1] F.J. Wortmann, G. Wortmann, J. Marsh, K. Meinert. J. Struct. Biol., 177 (2012) 553. [2] V. Signori, D. Lewis. Int. J. Cosmet. Sci., 19 (1997) 1-13.[3] A.M. Zalfen, G. Wortmann, F.J. Wortmann. SOEFW Journal, 131 (2005) 40.[4] F.J. Wortmann, M. Stapels, L. Chandra. J Appl.Polym.Sci., 113 (2009) 3336
Thermal analysis and synergistic tools for the development of a semi-permanent hair straightening technology
No full textThis research was carried out with the objective to develop a thermal analysis protocol into a method of damage assessment and claims support for a new semi-permanent hair straightening technology. The investigation determined the effects of the treatment on hair fibre composition and properties using Modulated Differential Scanning Calorimetry (MDSC) [1], Fourier Transform Infrared Spectroscopy (FTIR) [2], Gel Electrophoresis (SDS-PAGE) [3] and curl retention tests [4]. The effects of the new cysteamine treatment are compared with effects of a standard thioglycolate treatment and the daily use of straightening irons. Virgin, Caucasian hair was treated once with each chemical treatment and washed every day for 84 days. In a parallel study, hair was washed and straightened repeatedly using a standardised protocol at 190oC for 84 days. Samples were taken after 2, 28, 56 and 84 days for analysis by MDSC in water, ATR- and Trans-FTIR. Separate samples were treated once and subjected to curl retention tests and protein analysis. DSC measurements in water yield the keratin denaturation enthalpy (ΔHD), which relates to the thermal stability of the keratin intermediate filaments (KIFs), and the denaturation temperature (TD), which relates to the properties of the keratin associated-proteins (KAPs). The results show that chemical and thermal straightening cause a reduction in α-helix content and matrix viscosity. FTIR measurements give information on the formation of cysteic acid in the cuticle cells and the cortex. ATR-FTIR showed that the cysteamine–based treatment produces less cysteic acid in the cuticle layers than the standard treatment. Curl retention and SDS-PAGE were used to show the variability in the efficacy of the cysteamine treatment related to the heterogeneity of human hair. The results from both tests show that an individual’s hair will react with the product to a different extent, depending on the extractability of the keratin protein groups.In conclusion, we deduce that all straightening techniques, chemical and thermal, have a pronounced effect on the structural and chemical properties of hair fibres. These effects can be used to further develop and optimize this and related products. DSC has been shown to be an integral synergistic technique for the investigation of changes to hair morphology.This research was supported by the UK Technology Strategy Board under the Knowledge Transfer Partnership scheme.Cyril Keattch Award, Thermal Methods Group, Royal Society of Chemistry, 2014.[1] F.J. Wortmann, G. Wortmann, J. Marsh, K. Meinert. J. Struct. Biol., 177 (2012) 553. [2] V. Signori, D. Lewis. Int. J. Cosmet. Sci., 19 (1997) 1-13.[3] A.M. Zalfen, G. Wortmann, F.J. Wortmann. SOEFW Journal, 131 (2005) 40.[4] F.J. Wortmann, M. Stapels, L. Chandra. J Appl.Polym.Sci., 113 (2009) 3336
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Thermal Analysis of Human Hair, Modified by Disulphide Bond Breakage and Variable Alkylation
No full textThermal analysis of human hair, modified by disulphide bond breakage and variable alkylation Ian Jinks1, Gabriele Wortmann1, Prem Paul2, Franz J. Wortmann11School of Materials, University of Manchester, Manchester M13 9PL, UK.2Unilever Research and Development, Port Sunlight, Wirral, CH63 3JW, UK.Human hair, like other α-keratinous fibres, is a highly complex biomaterial. For the analysis of its mechanical and thermal properties it is, however, well described by a two-phase structure, which contains as morphological components the highly-ordered, crystalline intermediate filaments (IFs) and the less-ordered, amorphous matrix. Unique to α-keratin fibres are disulphide bonds, predominately found within the fibre matrix, which are known to play an important role in the stability and often are responsible for the unique mechanical properties exhibited by α-keratin fibres when compared to similar biomaterials. These bonds are, for instance, the chemical and structural basis for permanent waving and straightening treatments.Breaking of disulphide bonds through reduction and their modification through variable alkylation were carried out on untreated, brown, European human hair using a sequential ‘one-bath’ procedure established by Maclaren and Sweetman [1,2,3]. The subsequent alkylation of the reduced disulphide bonds is designed to prevent re-oxidation to reform the bonds, allowing fibre properties to be analysed. This modification was also intended to further investigate the premise put forward by Hall and Wolfram [4] that hair fibre stability could be restored after disulphide bond reduction through high molecular weight alkylation. This study attempts to determine the effects of disulphide bond reduction and alkylation with groups of different sizes and shapes on the thermal properties of human hair using differential scanning calorimetry (DSC) by, namely, investigating the humidity-dependent glass transition temperature Tg [5] as well as denaturation temperatures TD and enthalpies, ΔHD in water [6].Disulphide reduction and alkylation are shown to have a severe effect on the matrix, where both disulphide bond cleavage and plasticisation by the introduced alkyl chains contribute to the observed decrease in the humidity-dependent glass transition. The effect increases with the alkyl group chain length. Sizeable changes in the IF stability and integrity are shown by substantial reductions in denaturation enthalpies. However, it appears that at high water contents hydrophobic interactions between the alkyl chains are sufficient to kinetically impede the unfolding of the IFs to a similar extent as an untreated matrix. This is shown by a largely unchanged denaturation temperature after modification.[1] B. J. Sweetman and J. A. Maclaren, “Reduction of Wool Keratin by Tertiary Phosphines” Aust. J. Chem., 19 (1966) 2347–2354.[2] J. A. Maclaren, D. J. Kilpatrick, and A. Kirkpatrick, “Reduced Wool Fibres, their Preparation and Alkylation” Aust. J. Biol. Sci., 21 (1968) 805–813.[3] J. A. Maclaren and B. J. Sweetman, “Preparation of Reduced and S-Alkylated Wool Keratins Using Tri-N-Butylphosphine” Aust. J. Chem., 19 (1966) 2355–2360.[4] K. E. Hall and L. J. Wolfram, “Application of Theory of Hydrophobic Bonds to Hair Treatments” J. Soc. Cosmet. Chem., 28 (1977) 231–241. [5] F.J. Wortmann, M. Stapels, R. Elliot, and L. Chandra, “The Effect of Water on the Glass Transition of Human Hair” Biopolymers 81 (2006) 371-375.[6] F.J. Wortmann, C. Popescu, and G. Sendelbach, “Effects of Reduction on the Denaturation Kinetics of Human Hair” Biopolymers 89 (2008) 600-605
Thermal Analysis of Human Hair, Modified by Disulphide Bond Breakage and Variable Alkylation
No full textThermal analysis of human hair, modified by disulphide bond breakage and variable alkylation Ian Jinks1, Gabriele Wortmann1, Prem Paul2, Franz J. Wortmann11School of Materials, University of Manchester, Manchester M13 9PL, UK.2Unilever Research and Development, Port Sunlight, Wirral, CH63 3JW, UK.Human hair, like other α-keratinous fibres, is a highly complex biomaterial. For the analysis of its mechanical and thermal properties it is, however, well described by a two-phase structure, which contains as morphological components the highly-ordered, crystalline intermediate filaments (IFs) and the less-ordered, amorphous matrix. Unique to α-keratin fibres are disulphide bonds, predominately found within the fibre matrix, which are known to play an important role in the stability and often are responsible for the unique mechanical properties exhibited by α-keratin fibres when compared to similar biomaterials. These bonds are, for instance, the chemical and structural basis for permanent waving and straightening treatments.Breaking of disulphide bonds through reduction and their modification through variable alkylation were carried out on untreated, brown, European human hair using a sequential ‘one-bath’ procedure established by Maclaren and Sweetman [1,2,3]. The subsequent alkylation of the reduced disulphide bonds is designed to prevent re-oxidation to reform the bonds, allowing fibre properties to be analysed. This modification was also intended to further investigate the premise put forward by Hall and Wolfram [4] that hair fibre stability could be restored after disulphide bond reduction through high molecular weight alkylation. This study attempts to determine the effects of disulphide bond reduction and alkylation with groups of different sizes and shapes on the thermal properties of human hair using differential scanning calorimetry (DSC) by, namely, investigating the humidity-dependent glass transition temperature Tg [5] as well as denaturation temperatures TD and enthalpies, ΔHD in water [6].Disulphide reduction and alkylation are shown to have a severe effect on the matrix, where both disulphide bond cleavage and plasticisation by the introduced alkyl chains contribute to the observed decrease in the humidity-dependent glass transition. The effect increases with the alkyl group chain length. Sizeable changes in the IF stability and integrity are shown by substantial reductions in denaturation enthalpies. However, it appears that at high water contents hydrophobic interactions between the alkyl chains are sufficient to kinetically impede the unfolding of the IFs to a similar extent as an untreated matrix. This is shown by a largely unchanged denaturation temperature after modification.[1] B. J. Sweetman and J. A. Maclaren, “Reduction of Wool Keratin by Tertiary Phosphines” Aust. J. Chem., 19 (1966) 2347–2354.[2] J. A. Maclaren, D. J. Kilpatrick, and A. Kirkpatrick, “Reduced Wool Fibres, their Preparation and Alkylation” Aust. J. Biol. Sci., 21 (1968) 805–813.[3] J. A. Maclaren and B. J. Sweetman, “Preparation of Reduced and S-Alkylated Wool Keratins Using Tri-N-Butylphosphine” Aust. J. Chem., 19 (1966) 2355–2360.[4] K. E. Hall and L. J. Wolfram, “Application of Theory of Hydrophobic Bonds to Hair Treatments” J. Soc. Cosmet. Chem., 28 (1977) 231–241. [5] F.J. Wortmann, M. Stapels, R. Elliot, and L. Chandra, “The Effect of Water on the Glass Transition of Human Hair” Biopolymers 81 (2006) 371-375.[6] F.J. Wortmann, C. Popescu, and G. Sendelbach, “Effects of Reduction on the Denaturation Kinetics of Human Hair” Biopolymers 89 (2008) 600-605
Thermal Analysis of Human Hair, Modified by Disulphide Bond Breakage and Variable Alkylation
No full textThermal analysis of human hair, modified by disulphide bond breakage and variable alkylation Ian Jinks1, Gabriele Wortmann1, Prem Paul2, Franz J. Wortmann11School of Materials, University of Manchester, Manchester M13 9PL, UK.2Unilever Research and Development, Port Sunlight, Wirral, CH63 3JW, UK.Human hair, like other α-keratinous fibres, is a highly complex biomaterial. For the analysis of its mechanical and thermal properties it is, however, well described by a two-phase structure, which contains as morphological components the highly-ordered, crystalline intermediate filaments (IFs) and the less-ordered, amorphous matrix. Unique to α-keratin fibres are disulphide bonds, predominately found within the fibre matrix, which are known to play an important role in the stability and often are responsible for the unique mechanical properties exhibited by α-keratin fibres when compared to similar biomaterials. These bonds are, for instance, the chemical and structural basis for permanent waving and straightening treatments.Breaking of disulphide bonds through reduction and their modification through variable alkylation were carried out on untreated, brown, European human hair using a sequential ‘one-bath’ procedure established by Maclaren and Sweetman [1,2,3]. The subsequent alkylation of the reduced disulphide bonds is designed to prevent re-oxidation to reform the bonds, allowing fibre properties to be analysed. This modification was also intended to further investigate the premise put forward by Hall and Wolfram [4] that hair fibre stability could be restored after disulphide bond reduction through high molecular weight alkylation. This study attempts to determine the effects of disulphide bond reduction and alkylation with groups of different sizes and shapes on the thermal properties of human hair using differential scanning calorimetry (DSC) by, namely, investigating the humidity-dependent glass transition temperature Tg [5] as well as denaturation temperatures TD and enthalpies, ΔHD in water [6].Disulphide reduction and alkylation are shown to have a severe effect on the matrix, where both disulphide bond cleavage and plasticisation by the introduced alkyl chains contribute to the observed decrease in the humidity-dependent glass transition. The effect increases with the alkyl group chain length. Sizeable changes in the IF stability and integrity are shown by substantial reductions in denaturation enthalpies. However, it appears that at high water contents hydrophobic interactions between the alkyl chains are sufficient to kinetically impede the unfolding of the IFs to a similar extent as an untreated matrix. This is shown by a largely unchanged denaturation temperature after modification.[1] B. J. Sweetman and J. A. Maclaren, “Reduction of Wool Keratin by Tertiary Phosphines” Aust. J. Chem., 19 (1966) 2347–2354.[2] J. A. Maclaren, D. J. Kilpatrick, and A. Kirkpatrick, “Reduced Wool Fibres, their Preparation and Alkylation” Aust. J. Biol. Sci., 21 (1968) 805–813.[3] J. A. Maclaren and B. J. Sweetman, “Preparation of Reduced and S-Alkylated Wool Keratins Using Tri-N-Butylphosphine” Aust. J. Chem., 19 (1966) 2355–2360.[4] K. E. Hall and L. J. Wolfram, “Application of Theory of Hydrophobic Bonds to Hair Treatments” J. Soc. Cosmet. Chem., 28 (1977) 231–241. [5] F.J. Wortmann, M. Stapels, R. Elliot, and L. Chandra, “The Effect of Water on the Glass Transition of Human Hair” Biopolymers 81 (2006) 371-375.[6] F.J. Wortmann, C. Popescu, and G. Sendelbach, “Effects of Reduction on the Denaturation Kinetics of Human Hair” Biopolymers 89 (2008) 600-605
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