WorldWideScience

Sample records for added tannic acid

  1. 21 CFR 184.1097 - Tannic acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tannic acid. 184.1097 Section 184.1097 Food and... Substances Affirmed as GRAS § 184.1097 Tannic acid. (a) Tannic acid (CAS Reg. No. 1401-55-4), or hydrolyzable gallotannin, is a complex polyphenolic organic structure that yields gallic acid and either glucose or quinic...

  2. Compound list: tannic acid [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available tannic acid TAN 00093 ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Human/in_vitro/tannic_acid....Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vitro/tannic_acid....Rat.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Single/tannic_acid...archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/tannic_acid.Rat.in_vivo.Liver.Repeat.zip ...

  3. Tannic acid degradation by Klebsiella strains isolated from goat feces

    Directory of Open Access Journals (Sweden)

    Arezoo Tahmourespour

    2016-03-01

    Full Text Available Background and Objectives: Tannins are toxic polyphenols that either bind and precipitate or condense proteins. The high tannin content of some plants is the preliminary limitation of using them as a ruminant feed. So, the aim of this study was the isolation and characterization of tannic acid degrading bacterial strains from goat feces before and after feeding on Pis- tachio-Soft Hulls as tannin rich diet (TRD.Materials and Methods: Bacterial strains capable of utilizing tannic acid as sole carbon and energy source were isolated and characterized from goat feces before and after feeding on TRD. Tannase activity, maximum tolerable concentration and biodegradation potential were assessed.Results: Four tannase positive isolates were identified as Klebsiella pneumoniae. Isolated strains showed the maximum tolerable concentration of 64g/L of tannin. The tannic acid degradation percentage at a concentration of 15.0 g/L reached a maximum of 68% after 24 h incubation, and more than 98% after 72 h incubation. The pH of the medium also decreased along with tannic acid utilization.Conclusions: It is obvious that TRD induced adaptive responses. Thus, while the bacteria were able to degrade and detoxify the tannic acids, they had to adapt in the presence of high concentrations of tannic acid. So, these isolates have an amazing potential for application in bioremediation, waste water treatment, also reduction of tannins antinutritional effects in animal feeds.Keywords: Biodegradation; Goat feces; Klebsiella strains; Tannic acid

  4. Cerium-tannic acid passivation treatment on galvamzed steel

    Institute of Scientific and Technical Information of China (English)

    LIU Guangming; YU Fei; YANG Liu; TIAN Jihong; DU Nan

    2009-01-01

    A novel cerium-tannic acid passivation treatment was performed on galvanized steel. The corrosion resistance of cerium-tannic passivated samples was tested by dropping test with 0.5 wt.% CuSO4 aqueous solution. The mass loss per unit area of passivated samples was measured after the corrosion in 0.5 mol/L NaCl + 0.005 mol/L H2SO4 at room temperature for 96 h. The electrochemical behaviors of cerium, tannic acid, and cerium-tannic acid passivated samples on galvanized steel in 0.5 mol/L NaCI solution were investigated by polarization curves and electrochemical impendence spectra. The corrosion equivalent circuit was established according to the impedance characteristics. The results show that cerium-tannic acid treated samples exhibit better corrosion resistance than the sole cerium or tannic acid treated samples under the same condition. The mechanism of synergistic effect for cerium-tannic acid passivation on galvanized steel was discussed.

  5. Tannic acid-mediated green synthesis of antibacterial silver nanoparticles.

    Science.gov (United States)

    Kim, Tae Yoon; Cha, Song-Hyun; Cho, Seonho; Park, Youmie

    2016-04-01

    The search for novel antibacterial agents is necessary to combat microbial resistance to current antibiotics. Silver nanoparticles (AgNPs) have been reported to be effective antibacterial agents. Tannic acid is a polyphenol compound from plants with antioxidant and antibacterial activities. In this report, AgNPs were prepared from silver ions by tannic acid-mediated green synthesis (TA-AgNPs). The reaction process was facile and involved mixing both silver ions and tannic acid. The absorbance at 423 nm in the UV-Visible spectra demonstrated that tannic acid underwent a reduction reaction to produce TA-AgNPs from silver ions. The synthetic yield of TA-AgNPs was 90.5% based on inductively coupled plasma mass spectrometry analysis. High-resolution transmission electron microscopy and atomic force microscopy images indicated that spherical-shaped TA-AgNPs with a mean particle size of 27.7-46.7 nm were obtained. Powder high-resolution X-ray diffraction analysis indicated that the TA-AgNP structure was face-centered cubic with a zeta potential of -27.56 mV. The hydroxyl functional groups of tannic acid contributed to the synthesis of TA-AgNPs, which was confirmed by Fourier transform infrared spectroscopy. The in vitro antibacterial activity was measured using the minimum inhibitory concentration (MIC) method. The TA-AgNPs were more effective against Gram-negative bacteria than Gram-positive bacteria. The MIC for the TA-AgNPs in all of the tested strains was in a silver concentration range of 6.74-13.48 μg/mL. The tannic acid-mediated synthesis of AgNPs afforded biocompatible nanocomposites for antibacterial applications.

  6. Enhanced functional properties of tannic acid after thermal hydrolysis

    Science.gov (United States)

    Thermal hydrolysis processing of fresh tannic acid was carried out in a closed reactor at four different temperatures (65, 100, 150 and 200°C). Pressures reached in the system were 1.3 and 4.8 MPa at 150 and 200°C, respectively. Hydrolysis products (gallic acid and pyrogallol) were separated and qua...

  7. EFFECT OF WATER EXTRACTS OF CAROB PODS, TANNIC ACID, AND THEIR DERIVATIVES ON THE MORPHOLOGY AND GROWTH OF MICROORGANISMS.

    Science.gov (United States)

    HENIS, Y; TAGARI, H; VOLCANI, R

    1964-05-01

    The effect of aqueous extracts of carob (Ceratonia siliqua) pods, gallotannic acid, gallic acid, and catechol on several microorganisms was studied. Carob pod extract and tannic acid showed a strong antimicrobial activity toward some cellulolytic bacteria. On the basis of tannin content, to which antimicrobial effect was related, carob pod extracts inhibited Cellvibrio fulvus and Clostridium cellulosolvens at 15 mug/ml, Sporocytophaga myxococcoides at 45 mug/ml, and Bacillus subtilis at 75 mug/ml. The inhibiting concentrations for tannic acid were found to be 12, 10, 45, and 30 mug/ml, respectively. Gallic acid and catechol were much less effective. Tannic acid and the tannin fraction of carob extract exerted both bacteriostatic and bactericidal effects on C. fulvus. Respiration of C. fulvus in the presence of bactericidal concentrations of tannic acid or tannin fraction of carob extract was inhibited less than 30%. A partial formation of "protoplasts" by C. fulvus was obtained after 2 hr of incubation in a growth medium to which 20% sucrose, 0.15% MgSO(4).7H(2)O, and 10 to 50 mug/ml of tannic acid or 500mug/ml of penicillin, or both, had been added. Tannic acid and the tannin fraction of carob extract protected C. fulvus from metabolic lysis in sucrose solution. Although the growth of other microorganisms tested was only slightly affected, the morphology of some of them was drastically changed in the presence of subinhibitory concentrations of carob pod extracts of tannic acid. It is suggested that the site of action of tannins on sensitive microorganisms is primarily the cell envelope.

  8. Adsorption and Desorption Behavior of Tannic Acid in Aqueous Solution on Polyaniline Adsorbent

    Institute of Scientific and Technical Information of China (English)

    WANG Jiahong; JI Yanfen; DING Shaolan; MA Hongrui; HAN Xiaojing

    2013-01-01

    Tannic acid is generally considered as one of polyphenolic pollutants,which may cause severe threats to the environment.In this study,polyaniline adsorbent was synthesized by chemical oxidation to remove tannic acid in aqueous solutions.The adsorption amount of tannic acid varied greatly with pH of solution and strong adsorption was at pH 5.8-6.7.Coexisting cations,such as Na+,K+,and Ca2+,can enhance the adsorption of tannic acid on polyaniline,which may be contributed to the electrostatic interaction between tannic acid and polyaniline.The adsorption process could be well described by Langmuir model and the maximum adsorption capacity was 117.65 mg·g-1 at 35 ℃ and pH 6.0.The thermodynamic parameters calculated from the adsorption isotherms indicate that the adsorption of tannic acid is spontaneous and endothermic process.The polyaniline saturated with tannic acid can be desorbed in alkaline solution and regenerated adsorbent can be used repeatedly with high adsorption capacity,which implies that polyaniline adsorbents have a great potential in water purification for the removal of tannic acid.

  9. Reviewing the Tannic Acid Mediated Synthesis of Metal Nanoparticles

    Directory of Open Access Journals (Sweden)

    Tufail Ahmad

    2014-01-01

    Full Text Available Metal nanoparticles harbour numerous exceptional physiochemical properties absolutely different from those of bulk metal as a function of their extremely small size and large superficial area to volume. Naked metal nanoparticles are synthesized by various physical and chemical methods. Chemical methods involving metal salt reduction in solution enjoy an extra edge over other protocols owing to their relative facileness and capability of controlling particle size along with the attribute of surface tailoring. Although chemical methods are the easiest, they are marred by the use of hazardous chemicals such as borohydrides. This has led to inclination of scientific community towards eco-friendly agents for the reduction of metal salts to form nanoparticles. Tannic acid, a plant derived polyphenolic compound, is one such agent which embodies characteristics of being harmless and environmentally friendly combined with being a good reducing and stabilizing agent. In this review, first various methods used to prepare metal nanoparticles are highlighted and further tannic acid mediated synthesis of metal nanoparticles is emphasized. This review brings forth the most recent findings on this issue.

  10. The role of tannic acid and sodium citrate in the synthesis of silver nanoparticles

    Science.gov (United States)

    Ranoszek-Soliwoda, Katarzyna; Tomaszewska, Emilia; Socha, Ewelina; Krzyczmonik, Pawel; Ignaczak, Anna; Orlowski, Piotr; Krzyzowska, Małgorzata; Celichowski, Grzegorz; Grobelny, Jaroslaw

    2017-08-01

    We describe herein the significance of a sodium citrate and tannic acid mixture in the synthesis of spherical silver nanoparticles (AgNPs). Monodisperse AgNPs were synthesized via reduction of silver nitrate using a mixture of two chemical agents: sodium citrate and tannic acid. The shape, size and size distribution of silver particles were determined by UV-Vis spectroscopy, dynamic light scattering (DLS) and scanning transmission electron microscopy (STEM). Special attention is given to understanding and experimentally confirming the exact role of the reagents (sodium citrate and tannic acid present in the reaction mixture) in AgNP synthesis. The oxidation and reduction potentials of silver, tannic acid and sodium citrate in their mixtures were determined using cyclic voltammetry. Possible structures of tannic acid and its adducts with citric acid were investigated in aqueous solution by performing computer simulations in conjunction with the semi-empirical PM7 method. The lowest energy structures found from the preliminary conformational search are shown, and the strength of the interaction between the two molecules was calculated. The compounds present on the surface of the AgNPs were identified using FT-IR spectroscopy, and the results are compared with the IR spectrum of tannic acid theoretically calculated using PM6 and PM7 methods. The obtained results clearly indicate that the combined use of sodium citrate and tannic acid produces monodisperse spherical AgNPs, as it allows control of the nucleation, growth and stabilization of the synthesis process. [Figure not available: see fulltext.

  11. Tannic Acid Preferentially Targets Estrogen Receptor-Positive Breast Cancer

    Directory of Open Access Journals (Sweden)

    Brian W. Booth

    2013-01-01

    Full Text Available Research efforts investigating the potential of natural compounds in the fight against cancer are growing. Tannic acid (TA belongs to the class of hydrolysable tannins and is found in numerous plants and foods. TA is a potent collagen cross-linking agent; the purpose of this study was to generate TA-cross-linked beads and assess the effects on breast cancer cell growth. Collagen beads were stable at body temperature following crosslinking. Exposure to collagen beads with higher levels of TA inhibited proliferation and induced apoptosis in normal and cancer cells. TA-induced apoptosis involved activation of caspase 3/7 and caspase 9 but not caspase 8. Breast cancer cells expressing the estrogen receptor were more susceptible to the effects of TA. Taken together the results suggest that TA has the potential to become an anti-ER+ breast cancer treatment or preventative agent.

  12. Interactions of hybrid gold-tannic acid nanoparticles with human serum albumin.

    Science.gov (United States)

    Sekowski, Szymon; Tomaszewska, Emilia; Soliwoda, Katarzyna; Celichowski, Grzegorz; Grobelny, Jaroslaw

    2017-01-01

    Nanoparticles present a wide spectrum of chemical, biological, and physical properties which result in their usage in many branches of science. We present an investigation of the interaction between human serum albumin and hybrid gold-tannic acid nanoparticles synthesized via a chemical reduction method. The results obtained demonstrate that tannic acid can be a very effective reducing and stabilizing agent and allows monodisperse hybrid gold nanomaterial to be obtained. The synthesized hybrid gold-tannic acid nanoparticles strongly interact with human serum albumin by formation of protein-corona complexes. The strength of the interaction with albumin depends on the number of tannic acid molecules on the surface of the nanoparticles and the presence of citric acid. Nanoparticles of large size and rich in tannic acid react more strongly with the protein [K SV = (8.00 ± 0.2) × 10(5) M(-1)] compared with smaller ones [K SV = (6.83 ± 0.5) × 10(4) M(-1)] containing citric acid and low concentration of tannic acid.

  13. Electrospun Polymer Nanofibers Reinforced by Tannic Acid/Fe+++ Complexes

    Directory of Open Access Journals (Sweden)

    Weiqiao Yang

    2016-09-01

    Full Text Available We report the successful preparation of reinforced electrospun nanofibers and fibrous mats of polyvinyl alcohol (PVA via a simple and inexpensive method using stable tannic acid (TA and ferric ion (Fe+++ assemblies formed by solution mixing and pH adjustment. Changes in solution pH change the number of TA galloyl groups attached to the Fe+++ from one (pH < 2 to two (3 < pH < 6 to three (pH < 7.4 and affect the interactions between PVA and TA. At pH ~ 5.5, the morphology and fiber diameter size (FDS examined by SEM are determinant for the mechanical properties of the fibrous mats and depend on the PVA content. At an optimal 8 wt % concentration, PVA becomes fully entangled and forms uniform nanofibers with smaller FDS (p < 0.05 and improved mechanical properties when compared to mats of PVA alone and of PVA with TA (p < 0.05. Changes in solution pH lead to beads formation, more irregular FDS and poorer mechanical properties (p < 0.05. The Fe+++ inclusion does not alter the oxidation activity of TA (p > 0.05 suggesting the potential of TA-Fe+++ assemblies to reinforce polymer nanofibers with high functionality for use in diverse applications including food, biomedical and pharmaceutical.

  14. Forward osmosis filtration for removal of organic foulants: Effects of combined tannic and alginic acids.

    Science.gov (United States)

    Wang, Lin; Zhang, Wanzhu; Chu, Huaqiang; Dong, Bingzhi

    2016-03-15

    The filtration performance of combined organic foulants by forward osmosis (FO) in active-layer-facing-the-draw-solution (AL-facing-DS) orientation was investigated systematically. Tannic acid and alginate were used as model organic foulants for polysaccharides and humic dissolved organic matters, respectively. The FO could reject combined and single tannic acid and alginate foulants effectively. The more severe fouling flux decline, accompanied with lower combined foulants' retention, was observed with increasing proportions of tannic acid in the combined foulants-containing feed, which was ascribed mainly to the more severe fouling resulting from tannic acid adsorption within the porous support layer of the FO membrane compared to minor alginate deposition on the membrane surface. It was found that the higher the initial flux level and cross flow velocity, the faster the flux decline with lower mixed foulants retention. It was also revealed that the calcium ions in a basic solution enhanced the combined fouling flux reduction and combined foulants retention. As the major constituent of the combined fouling layer, the adsorption of tannic acid might play a more significant role in the mixed fouling of the FO membrane, which was probably influenced by permeation drag caused by water flux and chemical interactions induced by feed solution pH and calcium ion concentration.

  15. Tannic acid modified silver nanoparticles show antiviral activity in herpes simplex virus type 2 infection.

    Directory of Open Access Journals (Sweden)

    Piotr Orlowski

    Full Text Available The interaction between silver nanoparticles and herpesviruses is attracting great interest due to their antiviral activity and possibility to use as microbicides for oral and anogenital herpes. In this work, we demonstrate that tannic acid modified silver nanoparticles sized 13 nm, 33 nm and 46 nm are capable of reducing HSV-2 infectivity both in vitro and in vivo. The antiviral activity of tannic acid modified silver nanoparticles was size-related, required direct interaction and blocked virus attachment, penetration and further spread. All tested tannic acid modified silver nanoparticles reduced both infection and inflammatory reaction in the mouse model of HSV-2 infection when used at infection or for a post-infection treatment. Smaller-sized nanoparticles induced production of cytokines and chemokines important for anti-viral response. The corresponding control buffers with tannic acid showed inferior antiviral effects in vitro and were ineffective in blocking in vivo infection. Our results show that tannic acid modified silver nanoparticles are good candidates for microbicides used in treatment of herpesvirus infections.

  16. Tannic Acid as a Bio-Based Modifier of Epoxy/Anhydride Thermosets

    OpenAIRE

    Xiaoma Fei; Fangqiao Zhao; Wei Wei; Jing Luo; Mingqing Chen; Xiaoya Liu

    2016-01-01

    Toughening an epoxy resin by bio-based modifiers without trade-offs in its modulus, mechanical strength, and other properties is still a big challenge. This paper presents an approach to modify epoxy resin with tannic acid (TA) as a bio-based feedstock. Carboxylic acid-modified tannic acid (TA–COOH) was first prepared through a simple esterification between TA and methylhexahydrophthalic anhydride, and then used as a modifier for the epoxy/anhydride curing system. Owing to the chemical modifi...

  17. Highly Efficient Catalysis of Azo Dyes Using Recyclable Silver Nanoparticles Immobilized on Tannic Acid-Grafted Eggshell Membrane

    National Research Council Canada - National Science Library

    Liu, Xiaojing; Liang, Miao; Liu, Mingyue; Su, Rongxin; Wang, Mengfan; Qi, Wei; He, Zhimin

    2016-01-01

    ...) immobilized in tannic acid-modified eggshell membrane (Tan-ESM). Tannic acid, as a typical plant polyphenol from oak wood, was first grafted onto ESM fibers to serve as both the reductant and the stabilizer during the synthesis of AgNPs...

  18. Lipogenesis and lipid peroxidation in rat testes after long-term treatment with sucrose and tannic acid in drinking water.

    Science.gov (United States)

    Mašek, T; Starčević, K

    2016-06-30

    We studied the influence of long-term treatment with sucrose and tannic acid in drinking water on the fatty acid profile and lipid peroxidation in rat testes. Male Wistar rats were supplemented with sucrose (30% w/v) or with sucrose and tannic acid (sucrose 30% w/v, tannic acid 0.1% w/v) in drinking water. The treatment with sucrose elevated blood glucose levels in the plasma (p stress and hyperglycaemia, but it did not improve pathological changes in the fatty acid composition of the testis.

  19. Tannic acid Catalyzed an Efficient Synthesis of 2,4,5-Triaryl-1H-Imidazole

    Directory of Open Access Journals (Sweden)

    Shitole Nana Vikram

    2013-05-01

    Full Text Available Tannic acid (C76H52O46 has been found to be an efficient catalyst for one-pot synthesis of 2,4,5-triaryl substituted imidazoles by the reaction of an arylaldehyde, benzyl/benzoin and an ammonium acetate. The short reaction time and excellent yields making this protocol practical and economically attractive.

  20. Interactions between Phosphoric/Tannic Acid and Different Forms of FeOOH

    Directory of Open Access Journals (Sweden)

    Lefu Mei

    2015-01-01

    Full Text Available Alpha, beta, gamma, and delta hydroxyl ferric oxides (FeOOH, as the most common rust layers on iron surface, play different roles in iron preservation. Using modern surface analysis technologies such as X-ray diffraction (XRD, infrared spectra (IR, X-ray photoelectron spectroscopy (XPS, and scanning electron microscopy (SEM, we studied the interactions between these four types of synthetic FeOOH and phosphoric and tannic acid of different concentrations and proportions. A 3% tannic acid + 10% phosphoric acid + FeOOH was the most suitable formula for rust stabilizer and its reaction products were made up of iron phosphate and chelate of iron and tannin. This research provided technical basis in distinguishing FeOOH and selecting rust layer stabilizer for the preservation of iron, especially iron cultural relics.

  1. Tannic Acid as a Bio-Based Modifier of Epoxy/Anhydride Thermosets

    Directory of Open Access Journals (Sweden)

    Xiaoma Fei

    2016-08-01

    Full Text Available Toughening an epoxy resin by bio-based modifiers without trade-offs in its modulus, mechanical strength, and other properties is still a big challenge. This paper presents an approach to modify epoxy resin with tannic acid (TA as a bio-based feedstock. Carboxylic acid-modified tannic acid (TA–COOH was first prepared through a simple esterification between TA and methylhexahydrophthalic anhydride, and then used as a modifier for the epoxy/anhydride curing system. Owing to the chemical modification, TA–COOH could easily disperse in epoxy resin and showed adequate interface interaction between TA–COOH and epoxy matrix, in avoid of phase separation. The use of TA–COOH in different proportions as modifier of epoxy/anhydride thermosets was studied. The results showed that TA–COOH could significantly improve the toughness with a great increase in impact strength under a low loading amount. Moreover, the addition of TA–COOH also simultaneously improved the tensile strength, elongation at break and glass transition temperature. The toughening and reinforcing mechanism was studied by scanning electron microscopy (SEM, dynamic mechanical analysis (DMA and thermal mechanical analysis (TMA, which should be owned to the synergistic effect of good interface interaction, aromatic structure, decreasing of cross linking density and increasing of free volume. This approach allows us to utilize the renewable tannic acid as an effective modifier for epoxy resin with good mechanical and thermal properties.

  2. Efficacy of tannins from Mimosa pudica and tannic acid in neutralizing cobra (Naja kaouthia venom

    Directory of Open Access Journals (Sweden)

    FY Sia

    2011-01-01

    Full Text Available In the present study, the effectiveness of Mimosa pudica tannins (MPT in neutralizing the lethality of Naja kaouthia venom was compared with commercially derived tannins. Preincubation of MPT with N. kaouthia venom maintained 100% survival of mice after 24 hours. The mouse group in which there was no preincubation, no protection against the effects of the venom was observed. M. pudica tannin was found to be more effective in neutralizing the lethality of N. kaouthia venom when compared to commercial tannic acid. Two protein spots were missing in the two-dimensional gel electrophoresis (2-DE of the MPT treated mouse indicating the down-regulation of venom proteins. The results from this study indicated that tannins obtained from M. pudica are better than tannic acid in neutralizing the lethality of N. kaouthia venom in vitro. However, further investigations are required to establish that M. pudica has potential for treating N. kaouthia snakebites.

  3. Effects of heat treatment on chitosan nanocomposite film reinforced with nanocrystalline cellulose and tannic acid.

    Science.gov (United States)

    Rubentheren, V; Ward, Thomas A; Chee, Ching Yern; Nair, Praveena; Salami, Erfan; Fearday, Christopher

    2016-04-20

    This article presents an analysis of the influence of heat treatment on chitosan nanocomposite film. A series of samples comprising: pure chitosan film, chitosan film embedded with nanocrystalline cellulose (NCC), chitosan film crosslinked with tannic acid and chitosan film with a blend of NCC and tannic acid were heat treated using a convection oven. Fourier-transform-infrared spectroscopy (FTIR) and X-ray diffraction test (XRD) shows the changes in chemical interaction of the heat treated films. The heat treated films show significant improvements in moisture absorption. Tensile strength and Young's Modulus were increased up to 7MPa and 259MPa, respectively when the samples were subjected to heat treatment. For the NCC particles, a transmission electron microscope (TEM) was used to inspect the structural properties of cellulose particle in suspension form.

  4. Effect of calcium, tannic acid, phytic acid and pectin over iron uptake in an in vitro Caco-2 cell model.

    Science.gov (United States)

    Andrews, M; Briones, L; Jaramillo, A; Pizarro, F; Arredondo, M

    2014-04-01

    Calcium, phytic acid, polyphenols and fiber are major inhibitors of iron absorption and they could be found in excess in some diets, thereby altering or modifying the iron nutrition status. The purpose of this study is to evaluate the effect of calcium, tannic acid, phytic acid, and pectin over iron uptake, using an in vitro model of epithelial cells (Caco-2 cell line). Caco-2 cells were incubated with iron (10-30 μM) with or without CaCl2 (500 and 1,000 μM) for 24 h. Then, cells were challenged with phytic acid (50-150 μM); pectin (50-150 nM) or tannic acid (100-500 μM) for another 24 h. Finally, (55)Fe (10 μM) uptake was determined. Iron dialyzability was studied using an in vitro digestion method. Iron uptake in cells pre-incubated with 20 and 30 μM Fe was inhibited by CaCl2 (500 μM). Iron uptake decreased in cells cultured with tannic acid (300 μM) and CaCl2 (500-1,000 μM) (two-way ANOVA, p = 0.002). Phytic acid also decreased iron uptake mainly when cells were treated with CaCl2 (1,000 μM) (two-way ANOVA; p phytic or tannic acid (T test p Phytic acid combined with calcium is a strong iron uptake inhibitor. Pectin slightly decreased iron uptake with or without calcium. Tannic acid showed an unexpected behavior, inducing an increase on iron uptake, despite its low Fe dialyzability.

  5. Tannic acid NPs - synthesis and immobilization onto a solid surface in a one-step process and their antibacterial and anti-inflammatory properties.

    Science.gov (United States)

    Perelshtein, Ilana; Ruderman, Elena; Francesko, Antonio; Fernandes, Margarida M; Tzanov, Tzanko; Gedanken, Aharon

    2014-11-01

    Tannic acid nanoparticles were synthesized from an aqueous solution without the use of stabilizers via a sonochemical process. In order to avoid the dissolution of the formed nanoparticles, the sonochemical reaction was performed in the presence of a cotton fabric: following their formation, the tannic acid nanoparticles were embedded into the cotton substrate in a one-step process. The bioactive properties of the tannic acid coated surface were examined towards the inhibition of myeloperoxidase and collagenase, two major enzymes related with inflammatory processes. In addition, the antibacterial activity of the tannic acid nanoparticles coated textiles was evaluated against Staphylococcus aureus and Pseudomonas aeruginosa.

  6. Effects of Tannic Acid, Green Tea and Red Wine on hERG Channels Expressed in HEK293 Cells.

    Directory of Open Access Journals (Sweden)

    Xi Chu

    Full Text Available Tannic acid presents in varying concentrations in plant foods, and in relatively high concentrations in green teas and red wines. Human ether-à-go-go-related gene (hERG channels expressed in multiple tissues (e.g. heart, neurons, smooth muscle and cancer cells, and play important roles in modulating cardiac action potential repolarization and tumor cell biology. The present study investigated the effects of tannic acid, green teas and red wines on hERG currents. The effects of tannic acid, teas and red wines on hERG currents stably transfected in HEK293 cells were studied with a perforated patch clamp technique. In this study, we demonstrated that tannic acid inhibited hERG currents with an IC50 of 3.4 μM and ~100% inhibition at higher concentrations, and significantly shifted the voltage dependent activation to more positive potentials (Δ23.2 mV. Remarkably, a 100-fold dilution of multiple types of tea (green tea, oolong tea and black tea or red wine inhibited hERG currents by ~90%, and significantly shifted the voltage dependent activation to more positive potentials (Δ30.8 mV and Δ26.0 mV, respectively. Green tea Lung Ching and red wine inhibited hERG currents, with IC50 of 0.04% and 0.19%, respectively. The effects of tannic acid, teas and red wine on hERG currents were irreversible. These results suggest tannic acid is a novel hERG channel blocker and consequently provide a new mechanistic evidence for understanding the effects of tannic acid. They also revealed the potential pharmacological basis of tea- and red wine-induced biology activities.

  7. Effects of Tannic Acid, Green Tea and Red Wine on hERG Channels Expressed in HEK293 Cells.

    Science.gov (United States)

    Chu, Xi; Guo, Yusong; Xu, Bingyuan; Li, Wenya; Lin, Yue; Sun, Xiaorun; Ding, Chunhua; Zhang, Xuan

    2015-01-01

    Tannic acid presents in varying concentrations in plant foods, and in relatively high concentrations in green teas and red wines. Human ether-à-go-go-related gene (hERG) channels expressed in multiple tissues (e.g. heart, neurons, smooth muscle and cancer cells), and play important roles in modulating cardiac action potential repolarization and tumor cell biology. The present study investigated the effects of tannic acid, green teas and red wines on hERG currents. The effects of tannic acid, teas and red wines on hERG currents stably transfected in HEK293 cells were studied with a perforated patch clamp technique. In this study, we demonstrated that tannic acid inhibited hERG currents with an IC50 of 3.4 μM and ~100% inhibition at higher concentrations, and significantly shifted the voltage dependent activation to more positive potentials (Δ23.2 mV). Remarkably, a 100-fold dilution of multiple types of tea (green tea, oolong tea and black tea) or red wine inhibited hERG currents by ~90%, and significantly shifted the voltage dependent activation to more positive potentials (Δ30.8 mV and Δ26.0 mV, respectively). Green tea Lung Ching and red wine inhibited hERG currents, with IC50 of 0.04% and 0.19%, respectively. The effects of tannic acid, teas and red wine on hERG currents were irreversible. These results suggest tannic acid is a novel hERG channel blocker and consequently provide a new mechanistic evidence for understanding the effects of tannic acid. They also revealed the potential pharmacological basis of tea- and red wine-induced biology activities.

  8. Physiological and Molecular Response of Prorocentrum minimum to Tannic Acid: An Experimental Study to Evaluate the Feasibility of Using Tannic Acid in Controling the Red Tide in a Eutrophic Coastal Water

    Directory of Open Access Journals (Sweden)

    Byungkwan Jeong

    2016-05-01

    Full Text Available Bioassay and gene expression experiments were conducted in order to evaluate the growth and physiology of Prorocentrum minimum isolated from a eutrophic coastal water in response to tannic acid. In the bioassay experiments, variations in abundance, chlorophyll (chl a concentration, maximum fluorescence (in vivo Fm, and photosynthetic efficiency (Fv/Fm were measured over the course of a seven-day incubation. Moreover, stress-related gene expression in both the control and an experimental (2.5 ppm TA treatment group was observed for 24 h and 48 h. The molecular markers used in this study were the heat shock proteins (Hsp70 and Hsp90 and cyclophilin (CYP. The findings show that P. minimum can thrive and grow at low concentrations (<2.5 ppm of tannic acid, and, above this concentration, cells begin to slow down development. In addition, TA concentration of 10 ppm halted photosynthetic activity. At the molecular level, treatment with tannic acid increased the expression of Hsp70, Hsp90, and CYP, and heat shock proteins are more upregulated than the cyclophilin gene. Exposure to tannic acid increased the expression of stress factors over time (48 h by 10- to 27-fold the expression level of the control group. These results suggest that tannic acid can be used to control harmful algal blooms such as those containing P. minimum in eutrophic coastal waters.

  9. Adsorption of tannic acid on polyelectrolyte monolayers determined in situ by streaming potential measurements.

    Science.gov (United States)

    Oćwieja, M; Adamczyk, Z; Morga, M

    2015-01-15

    Physicochemical characteristics of tannic acid (tannin) suspensions comprising its stability for a wide range of ionic strength and pH were thoroughly investigated using UV-vis spectrophotometry, dynamic light scattering and microelectrophoretic measurements. These studies allowed to determine the hydrodynamic diameter of the tannic acid that was 1.63 nm for the pH range 3.5-5.5. For pH above 6.0 the hydrodynamic diameter significantly decreased as a result of the tannin hydrolysis. The electrophoretic mobility measurements confirmed that tannic acid is negatively charged for these values of pH and ionic strength 10(-4)-10(-2) M. Therefore, in order to promote adsorption of tannin molecules on negatively charged mica, the poly(allylamine hydrochloride) (PAH) supporting monolayers were first adsorbed under diffusion transport conditions. The coverage of polyelectrolyte monolayers was regulated by changing bulk concentration of PAH and the adsorption time. The electrokinetic characteristics of bare and PAH-covered mica were determined using the streaming potential measurements. The zeta potential of these PAH monolayers was highly positive, equal to 46 mV for ionic strength of 10(-2) M. The kinetics of tannin adsorption on these PAH supporting monolayers was evaluated by the in situ the streaming potential measurements. The zeta potential of PAH monolayers abruptly decreases with the adsorption of tannin molecules that was quantitatively interpreted in terms of the three-dimensional electrokinetic model. The acid-base characteristics of tannin monolayers were acquired via the streaming potential measurements for a broad range of pH. The obtained results indicate that it is possible to control adsorption of tannin on positively charged surfaces in order to designed new multilayer structures of desirable electrokinetic properties and stability.

  10. Effect of tannic acid solution on collagen structures for dental restoration.

    Science.gov (United States)

    Natsir, N; Wakasa, K; Yoshida, Y; Satou, N; Shintani, H

    1999-08-01

    This study examined the effect of tannic acid solution on dissolution of dentine collagen and morphological aspects of tendon collagen. Using root dentine, which was cut off from bovine anterior tooth, dentine powders were obtained by the pulverization and lyophilization. They were subject to an application of 1, 3, 5 or 10% tannic acid (TA) solution for 1, 3, 6, 12 or 24 h. TA-treated dentine powders were treated with 40% phosphoric acid (PA) for 30 s at 20 degrees C and additionally with trypsin. Released hydroxyproline in Woessner's assay after a hydrolysis in 6 N HCl at 110 degrees C for 20 h was assumed to be dissolved dentine collagen. Released hydroxyproline in a control sample without acid treatment decreased from 100 to about 60% with increased TA concentration of 1 to 10%, and decreased with increased incubation times of 1 to 24 h when applied by 5% TA solution. Scanning electron microscopy results established the morphological effect of their surface characteristics due to such treatments as 40% PA for 30 s and 5% TA for 6 h, or 40% PA after 5% TA treatment, yielding collagen structures protected by TA to attack from phosphoric acid.

  11. Development and Preliminary Assessment of Hemoperfusion Cartridge with Tannic Acid for Toxic Proteins' Precipitation: An In Vitro Model

    Directory of Open Access Journals (Sweden)

    Valquíria Miwa Hanai Yoshida

    2016-09-01

    Full Text Available Charcoal hemoperfusion (CHP is one of the extracorporeal removal techniques that are used to remove toxins from the body. CHP generally is considered the preferred method for extracorporeal extraction of several toxins—toxins that are adsorbed by activated charcoal. Assessments of the tannic acid's protective effects on ophidian poisoning are associated with the toxic proteins' precipitation by tannic acid. The challenge in treating a snakebite lies in removing the injected poison with minimal damage to blood constituent proteins. An alternative is CHP, and this investigation proposed to develop a column for hemoperfuser cartridge, combining charcoal granules trapped between layers of polymeric material conjugated to tannic acid, using an in vitro model scaled to the Wistar rat, which can be tested in an animal model. The cartridge was evaluated using the 22 full factorial design, in duplicate, as a method to study the effects of granulated-charcoal size and tannic acid concentration on the hematologic profile (platelet and leukocyte counts and biochemical profile (total serum protein and albumin dosages of sheep blood. The results demonstrate that charcoal in hemoperfuser cartridge: (1 decreases the serum in sheep blood volume, as consequence, (2 increases the serum proteins' concentration, and (iii exerts slight influence on albumin. The inclusion of tannic acid in hemoperfuser column precipitates some of serum proteins and albumin, decreasing their concentrations in the plasma serum. In conclusion, based on these effects we can suggest the use of 0.02 g tannic acid concentration and 8–20 mesh granulated charcoal in hemoperfuser cartridge for precipitating toxic proteins from snake venoms.

  12. Improved Performance of Lipase Immobilized on Tannic Acid-Templated Mesoporous Silica Nanoparticles.

    Science.gov (United States)

    Jiang, Yanjun; Sun, Wenya; Zhou, Liya; Ma, Li; He, Ying; Gao, Jing

    2016-08-01

    Mesoporous silica nanoparticles were synthesized by using tannic acid as a pore-forming agent, which is an environmentally friendly, cheap, and non-surfactant template. SEM and TEM images indicated that the tannic acid-templated mesoporous silica nanoparticles (TA-MSNs) are monodisperse spherical-like particles with an average diameter of 195 ± 16 nm. The Brunauer-Emmett-Teller (BET) results showed that the TA-MSNs had a relatively high surface area (447 m(2)/g) and large pore volume (0.91 cm(3)/g), and the mean pore size was ca. 10.1 nm. Burkholderia cepacia lipase was immobilized on the TA-MSNs by physical adsorption for the first time, and the properties of immobilized lipase (BCL@TA-MSNs) were investigated. The BCL@TA-MSNs exhibited satisfactory thermal stability; strong tolerance to organic solvents such as methanol, ethanol, isooctane, n-hexane, and tetrahydrofuran; and high operational reusability when BCL@TA-MSNs were applied in esterification and transesterification reactions. After recycling 15 times in the transesterification reaction for biodiesel production, over 85 % of biodiesel yield can be maintained. With these desired characteristics, the TA-MSNs may provide excellent candidates for enzyme immobilization.

  13. Tannic acid mitigates the DMBA/croton oil-induced skin cancer progression in mice.

    Science.gov (United States)

    Majed, Ferial; Rashid, Summya; Khan, Abdul Quaiyoom; Nafees, Sana; Ali, Nemat; Ali, Rashid; Khan, Rehan; Hasan, Syed Kazim; Mehdi, Syed Jafar; Sultana, Sarwat

    2015-01-01

    Skin cancer is the most common malignancy in the world and also one of the major causes of death worldwide. The toxic environmental pollutant 7,12-dimethylbenz[a]anthracene (DMBA) is a skin-specific carcinogen. Tannic acid (TA) is reported to be effective against various types of chemical-induced toxicities and carcinogenesis as well. In the present study, we have evaluated the therapeutic potential of tannic acid in DMBA + croton oil-induced skin cancer in Swiss albino mice. Protective effect of TA against skin cancer was evaluated in terms of antioxidant enzymes activities, lipid peroxidation, histopathological changes and expression of inflammation and early tumour markers. DMBA + croton oil causes depletion of antioxidant enzymes (p croton oil-induced toxicity through a protective mechanism that involves the reduction of oxidative stress as well as COX-2, i-NOS, PCNA protein expression and level of proinflammatory cytokine such as IL-6 release at a very significant level (p croton oil-induced tumour promotional potential possibly by inhibiting oxidative and inflammatory responses and acts as antioxidant, anti-inflammatory and antiproliferative agent.

  14. Effects of Ascorbic Acid, Phytic Acid and Tannic Acid on Iron Bioavailability from Reconstituted Ferritin Measured by an In Vitro Digestion/Caco-2 Cell Model

    Science.gov (United States)

    The effects of ascorbic acid, phytate and tannic acid on Fe bioavailability from Fe supplied as ferritin was compared to FeSO4 using an in vitro digestion/Caco-2 cell model. Horse spleen ferritin (HSF) was chemically reconstituted into a plant-type ferritin (P-HSF). In the presence of ascorbic acid...

  15. Fe-tannic acid complex dye as photo sensitizer for different morphological ZnO based DSSCs

    Science.gov (United States)

    Çakar, Soner; Özacar, Mahmut

    2016-06-01

    In this paper we have synthesized different morphological ZnO nanostructures via microwave hydrothermal methods at low temperature within a short time. We described different morphologies of ZnO at different Zn(NO3)2/KOH mole ratio. The ZnO nanostructures were characterized via X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and UV-vis spectrophotometry. All ZnO structures have hexagonal wurtzite type structures. The FESEM images showed various morphologies of ZnO such as plate, rod and nanoparticles. Dye sensitized solar cells have been assembled by these different morphological structures photo electrode and tannic acid or Fe-tannic acid complex dye as sensitizer. We have achieved at maximum efficiencies of photovoltaic cells prepared with ZnO plate in all dye systems. The conversion efficiencies of dye sensitized solar cells are 0.37% and 1.00% with tannic acid and Fe-tannic acid complex dye, respectively.

  16. Effect of tannic acid-fish scale gelatin hydrolysate hybrid nanoparticles on intestinal barrier function and α-amylase activity.

    Science.gov (United States)

    Wu, Shao-Jung; Ho, Yi-Cheng; Jiang, Shun-Zhou; Mi, Fwu-Long

    2015-07-01

    Practical application of tannic acid is limited because it readily binds proteins to form insoluble aggregates. In this study, tannic acid was self-assembled with fish scale gelatin hydrolysates (FSGH) to form stable colloidal complex nanoparticles. The nanoparticles prepared from 4 mg ml(-1) tannic acid and 4 mg ml(-1) FSGH had a mean particle size of 260.8 ± 3.6 nm, and showed a positive zeta potential (20.4 ± 0.4 mV). The nanoparticles acted as effective nano-biochelators and free radical scavengers because they provided a large number of adsorption sites for interaction with heavy metal ions and scavenging free radicals. The maximum adsorption capacity for Cu(2+) ions was 123.5 mg g(-1) and EC50 of DPPH radical scavenging activity was 21.6 ± 1.2 μg ml(-1). Hydroxyl radical scavenging effects of the nanoparticles were investigated by electron spin resonance spectroscopy. The copper-chelating capacity and free radical scavenging activity of the nanoparticles were associated with their capacity to inhibit Cu(2+) ion-induced barrier impairment and hyperpermeability of Caco-2 intestinal epithelial tight junction (TJ). However, α-amylase inhibitory activity of the nanoparticles was significantly lower than that of free tannic acid. The results suggest that the nanoparticles can ameliorate Cu(2+) ion induced intestinal epithelial TJ dysfunction without severely inhibiting the activity of the digestive enzymes.

  17. Effect of tannic acid on corrosion of mild steel in boiler system. Boiler kei deno nanko no fushoku ni taisuru tanninsan no fushoku yokusei koka

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Y.; Imahama, T.; Wake, T. (Japan Organo Co. Ltd., Tokyo (Japan)); Sekine, I.; Kawase, T.; Shiromoto, T.; Yuasa, M. (Science University of Tokyo, Tokyo (Japan). Facutly of Science and Technology)

    1992-08-15

    Tannic acid was studied as a corrosion inhibitor in boiler system from the view points of safety and economy. Hydrolytic tannin extracted from gallnut was used as tannic acid and gallic acid, hydrazine and sodium sulfite were used as the reference samples. A mild steel (JIS SS 400) was used for the test steel. The following test were made in the comparative experiments: the measurement of polarization curve of the mild steel by electrochemical method, and the analyses of surface change of mild steel by using a scanning tunnelling microscope and the X ray photoelectron spectrography, etc. Tannic acid exhibits the corrosion inhibiting effect identical to those of reference samples under alkaline condition. Tannic acid has the inhibiting effect even under high temperature and pressure condition and the maximum inhibition efficiency is 97%. Tannic acid exhibits the adsorption type inhibition under the neutral condition. Under alkaline condition, tannic acid inhibits corrosion of steel not only as an effective oxygen scavenger but also an effective passivating effect forming Fe[sub 3]O[sub 4]. Tannic acid is concluded as an effective oxygen inhibitor. 17 refs., 11 figs.

  18. 添加单宁酸对青贮葛藤茎叶品质的影响%Effects of Tannic Acid Additive on the Quality of Kudzu Stem and Leaf Silage

    Institute of Scientific and Technical Information of China (English)

    杨冬梅; 陶双伦; 梁静; 李俊年

    2012-01-01

    To investigate the effect of tannic acid additive on the quality of kudzu silage, the sensory evaluation of kudzu silage added 3% and 4% tannic acid was carried out. Both nutrients and organic acid contents were assayed and the loss rate of dry matter in silage. Results showed that tannic acid could significantly decrease the loss rate of dry matter (P<0. 05) , while significantly increasing the concentrations of water soluble carbohydrate (WSC) and neutral detergent fiber (NDF) of kudzu silage (P<0. 05). Propionic acid and butyric acid were not detected in kudzu stem and leaf silage with added tannic acid. Kudzu stem and leaf silage with added tannic acid was light green and had an acid flavor. Results indicated that adding tannic acid in kudzu silage is favorable to maintain nutrients and improve the quality of silage.%为探讨添加单宁酸对青贮葛藤(Pueraria lobata(Willd.)Ohwi)茎叶品质的影响,以青绿葛藤茎叶为原料,添加3%和4%单宁酸青贮60 d后,对其进行感官鉴定,并进行有机酸、干物质损失率及营养成分的分析.结果表明:添加单宁酸的贮葛藤茎叶质地松散完整,具有酸香味,干物质损失率显著降低(P<0.05);可溶性碳水化合物和中性洗涤纤维含量显著增加(P<0.05);在添加单宁酸的青贮葛藤茎叶中,未检测出丙酸和丁酸.因此,葛藤青贮时添加单宁酸有利于营养物质的保持,可明显提高其品质.

  19. Ozonation of tannic acid to model biomass pretreatment for bioethanol production.

    Science.gov (United States)

    Peretz, Roi; Gerchman, Yoram; Mamane, Hadas

    2017-10-01

    Lignocellulosic biomass is a promising feedstock for ethanol production, but lignin, a polyphenol, hampers the use of enzymes for its saccharification; pretreatment is thus key to preparing such feedstock. Ozonation was previously demonstrated as an effective pretreatment, but claimed to be uneconomical due to the assumed need for lignin mineralization. We analyzed, for the first time, ozonation of highly concentrated tannic acid (TA) solution (60g/L) as a lignin model. Most of the TA disappeared within 3.5h, following triple-phase kinetics with two transition points: at 7min and 60min of ozonation for 0.4L ozone reactor. Maximal enzymatic activity was found at the first transition point, demonstrating that very short ozonation that results in partial decomposition of TA, is enough to remediate TA's negative effect on cellulase activity. Short ozonation could decrease energy input by up to 97%, making ethanol production more economically competitive. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Analysis of the Evolution of Tannic Acid Stabilized Gold Nanoparticles Using Mie Theory

    Directory of Open Access Journals (Sweden)

    Assia Rachida Senoudi

    2014-01-01

    Full Text Available Spherical gold nanoparticles (GNPs have been synthesized in aqueous solutions using sodium citrate (SC and tannic acid (TA as reducing and stabilizing agents. Upon addition of TA and compared to the GNP TA-free aqueous solutions, a reduction of the GNPs size and consequently a dramatic change of their optical properties have been observed and quantitatively analyzed using Mie theory. An increase in the concentration of TA reveals a modification of the colloidal solution refractive index that is evidenced by the shift in the peak position of the localized surface plasmon resonance (LSPR band. The variations of the peak absorbance with the TA concentration are examined in the low and high concentration regimes.

  1. Tannic acid assisted synthesis of flake-like hydroxyapatite nanostructures at room temperature

    Science.gov (United States)

    Vázquez, Maricela Santana; Estevez, O.; Ascencio-Aguirre, F.; Mendoza-Cruz, R.; Bazán-Díaz, L.; Zorrila, C.; Herrera-Becerra, R.

    2016-09-01

    A simple and non-expensive procedure was performed to synthesize hydroxyapatite (HAp) flake-like nanostructures, by using a co-precipitation method with tannic acid as stabilizing agent at room temperature and freeze drying. Samples were synthesized with two different salts, Ca(NO3)2 and CaCl2. X-ray diffraction analysis, Raman spectroscopy, scanning and transmission electron microscopy characterizations reveal Ca10(PO4)6(OH)2 HAp particles with hexagonal structure and P63/m space group in both cases. In addition, the particle size was smaller than 20 nm. The advantage of this method over the works reported to date lies in the ease for obtaining HAp particles with a single morphology (flakes), in high yield. This opens the possibility of expanding the view to the designing of new composite materials based on the HAp synthesized at room temperature.

  2. Hyaluronan/Tannic Acid Nanoparticles Via Catechol/Boronate Complexation as a Smart Antibacterial System.

    Science.gov (United States)

    Montanari, Elita; Gennari, Arianna; Pelliccia, Maria; Gourmel, Charlotte; Lallana, Enrique; Matricardi, Pietro; McBain, Andrew J; Tirelli, Nicola

    2016-12-01

    Nanoparticles based on hyaluronic acid (HA) are designed to deliver tannic acid (TA) as an antimicrobial agent. The presence of HA makes these particles potentially useful to target bacteria that colonize cells presenting HA membrane receptors (e.g. CD44), such as macrophages. HA bearing 3-aminophenyl boronic acid groups (HA-APBA) is reacted with TA, yielding nanoparticles with a size that decreases with decreasing HA molecular weight (e.g. 200 nm for 44 kDa, 400 nm for 737 kDa). The boronate esters make the nanoparticles stable at physiological pH, but their hydrolysis in an acidic environment (pH = 5) leads to swelling/solubilization, therefore potentially allowing TA release in endosomal compartments. We have assessed the nanoparticle toxicity profile (on RAW 264.7 macrophages) and their antimicrobial activity (on E. coli and on both methicillin-sensitive and -resistant S. aureus). The antibacterial effect of HA-APBA/TA nanoparticles was significantly higher than that of TA alone, and has very similar activity to TA coformulated with a reducing agent (ascorbic acid), which indicates both the nanoparticles to protect TA catechols from oxidation, and the effective release of TA after nanoparticle internalization. Therefore, there is potential for these nanoparticles to be used in stable, effective, and potentially targetable nanoparticle-based antimicrobial formulations.

  3. Highly Efficient Catalysis of Azo Dyes Using Recyclable Silver Nanoparticles Immobilized on Tannic Acid-Grafted Eggshell Membrane

    Science.gov (United States)

    Liu, Xiaojing; Liang, Miao; Liu, Mingyue; Su, Rongxin; Wang, Mengfan; Qi, Wei; He, Zhimin

    2016-10-01

    In this study, a facile one-step synthesis of a novel nanocomposite catalytic film was developed based on silver nanoparticles (AgNPs) immobilized in tannic acid-modified eggshell membrane (Tan-ESM). Tannic acid, as a typical plant polyphenol from oak wood, was first grafted onto ESM fibers to serve as both the reductant and the stabilizer during the synthesis of AgNPs. The morphology, constitution, and thermal stability of the resulting AgNPs@Tan-ESM composites were fully characterized to explain the excellent catalytic efficiency of AgNPs@Tan-ESM composites. These composite catalysts were applied to the degradation of azo dyes which exhibited the high catalytic activity toward Congo red and methyl orange according to the kinetic curves. More importantly, they can be easily recovered and reused for many times because of their good stability.

  4. Highly Efficient Catalysis of Azo Dyes Using Recyclable Silver Nanoparticles Immobilized on Tannic Acid-Grafted Eggshell Membrane.

    Science.gov (United States)

    Liu, Xiaojing; Liang, Miao; Liu, Mingyue; Su, Rongxin; Wang, Mengfan; Qi, Wei; He, Zhimin

    2016-12-01

    In this study, a facile one-step synthesis of a novel nanocomposite catalytic film was developed based on silver nanoparticles (AgNPs) immobilized in tannic acid-modified eggshell membrane (Tan-ESM). Tannic acid, as a typical plant polyphenol from oak wood, was first grafted onto ESM fibers to serve as both the reductant and the stabilizer during the synthesis of AgNPs. The morphology, constitution, and thermal stability of the resulting AgNPs@Tan-ESM composites were fully characterized to explain the excellent catalytic efficiency of AgNPs@Tan-ESM composites. These composite catalysts were applied to the degradation of azo dyes which exhibited the high catalytic activity toward Congo red and methyl orange according to the kinetic curves. More importantly, they can be easily recovered and reused for many times because of their good stability.

  5. A Study on Tannic Acid-doped Polypyrrole Films on Gold Electrodes for Selective Electrochemical Detection of Dopamine

    OpenAIRE

    Shouzhuo Yao; Yunlong Li; Zhili Li; Qingji Xie; Ling Jiang

    2005-01-01

    Tannic acid-doped polypyrrole (PPY/TA) films have been grown on gold electrodes for selective electrochemical detection of dopamine (DA). Electrochemical quartz crystal microbalance (EQCM) studies revealed that, in vivid contrast to perchlorate-doped polypyrrole films (PPY/ClO4 -), the redox switching of PPY/TA films in aqueous solutions involved only cation transport if the solution pH was greater than 3∼4. The PPY/TA Au electrodes also exhibited attractive permselectivity for electroactive ...

  6. Inactivation of human norovirus surrogates by benzalkonium chloride, potassium peroxymonosulfate, tannic acid, and gallic acid.

    Science.gov (United States)

    Su, Xiaowei; D'Souza, Doris H

    2012-09-01

    Novel methods to effectively disinfect contact surfaces and prevent human norovirus transmission are essential. The effect of benzalkonium chloride (BAC), potassium peroxymonosulfate (KPMS), tannic acid (TA), and gallic acid (GA) on enteric virus surrogates, murine norovirus (MNV-1), feline calicivirus (FCV-F9), and bacteriophage MS2 was studied. Viruses at high (∼7 log₁₀ PFU/mL) or low (∼5 log₁₀ PFU/mL) titers were mixed with equal volumes of BAC (0.2, 0.5, and 1 mg/mL), KPMS (5, 10, and 20 mg/mL), TA (0.02 and 0.2 mg/mL), GA (0.2, 0.4, and 0.8 mg/mL), or water and incubated for 2 h at room temperature. Viral infectivity after triplicate treatments was evaluated using plaque assays in duplicate. Low titers of FCV-F9 and MNV-1 were completely reduced, while low-titer MS2 was reduced by 1.7-1.8 log₁₀ PFU/mL with BAC at all three concentrations. High-titer FCV-F9 was reduced by 2.87, 3.08, and 3.25 log₁₀ PFU/mL, and high-titer MNV-1 was reduced by 1.55, 2.32, and 2.75 log₁₀ PFU/mL with BAC at 0.1, 0.25, and 0.5 mg/mL, respectively. High-titer MS2 was reduced by ∼2 log₁₀ PFU/mL with BAC at all three concentrations. KPMS at all three concentrations reduced high and low titers of FCV-F9 and MS2 and low-titer MNV-1 to undetectable levels, while high-titer MNV-1 was reduced by 0.92 and 3.44 log₁₀ PFU/mL with KMPS at 2.5 and 5 mg/mL, respectively. TA at 0.2 mg/mL only reduced high-titer FCV-F9 by 0.98 log₁₀ PFU/mL and low-titer FCV-F9 by 1.95 log₁₀ PFU/mL. GA at 0.1, 0.2, and 0.4 mg/mL reduced low-titer FCV-F9 by 2.50, 2.36, and 0.86 log₁₀ PFU/mL, respectively with negligible effects against high-titer FCV-F9. BAC and KPMS show promise to be used as broad-spectrum contact surface disinfectants for prevention of noroviral surrogate contamination.

  7. Biocompatible and biodegradable poly(Tannic Acid) hydrogel with antimicrobial and antioxidant properties.

    Science.gov (United States)

    Sahiner, Nurettin; Sagbas, Selin; Sahiner, Mehtap; Silan, Coskun; Aktas, Nahit; Turk, Mustafa

    2016-01-01

    A novel resourceful bulk poly(Tannic Acid) (p(TA)) hydrogel was prepared by crosslinking TA molecules with an epoxy crosslinker, trimethylolpropane triglycidyl ether (TMPGDE), in an autoclave at 90°C for 2h. The obtained p(TA) hydrogels were in disk form and have highly porous morphology. The swelling characteristics of p(TA) hydrogels were investigated in wound healing pH conditions of pH 5.4, 7.4, and 9 at 37.5°C, and the hydrogels showed good swelling and moisture content behavior. Especially, p(TA) hydrogels were found to be sensitive to pH 9 with 1669% maximum swelling. P(TA) hydrogels were completely degraded at pH 9 hydrolytically in 9 days. Total phenol contents and the effects of scavenging ABTS(+) radicals of degraded p(TA) hydrogels at pH 5.4, 7.4, and 9 were evaluated and calculated in terms of gallic acid equivalent and trolox equivalent antioxidant capacity, respectively, and found to be very effective. Moreover, degraded p(TA) hydrogels display strong antimicrobial behavior against gram positive Staphylococcus aureus, Bacillus subtilis, gram negative Pseudomonas aeruginosa bacteria strains and Candida albicans fungus strain. The WST-1 results indicated that bulk p(TA) hydrogels have no cyctotoxicity to the L929 fibroblast cell line in vitro.

  8. Tannic Acid as a Potential Modulator of Norfloxacin Resistance in Staphylococcus Aureus Overexpressing norA.

    Science.gov (United States)

    Diniz-Silva, Helena Taina; Cirino, Isis Caroline da Silva; Falcão-Silva, Vivyanne Dos Santos; Magnani, Marciane; de Souza, Evandro Leite; Siqueira-Júnior, José P

    2016-01-01

    Tannins have shown inhibitory effects against pathogenic bacteria, and these properties make tannins potential modifying agents in bacterial resistance. The minimum inhibitory concentration (MIC) of tannic acid (TA), gallic acid (GA) and norfloxacin (Nor) against Staphylococcus aureus SA-1119 (NorA-effluxing strain) was determined using broth microdilution tests. To assess the modulation of antibiotic resistance, the MIC of Nor was determined in growth media with or without TA or GA at a subinhibitory concentration (1/4 MIC). The checkerboard method was performed to obtain the fractional inhibitory concentration index (FICI) for the combined application of TA and Nor. TA displayed a weak inhibitory effect (MIC 512 μg/ml) against S. aureus SA-1119, while no inhibitory effect was displayed by GA (MIC >512 μg/ml). However, when TA was tested at a subinhibitory concentration in combination with Nor, the MIC of Nor against S. aureus SA-1119 decreased from 128 to 4 μg/ml (32-fold); this effect was not observed for GA. In the checkerboard assay, the MIC of TA and Nor decreased from 512 to 128 μg/ml (4-fold) and from 128 to 8 μg/ml (16-fold), respectively. The combination of TA and Nor presented an FICI as low as 0.31, which indicates a synergistic interaction. TA is a potential agent for increasing the clinical efficacy of Nor to control resistant S. aureus. © 2016 S. Karger AG, Basel.

  9. Influence of the addition orders of guar gum and tannic acid on sulfide flotation%古尔胶和鞣酸添加方式对硫化矿浮选的影响

    Institute of Scientific and Technical Information of China (English)

    邱仙辉; 孙传尧

    2014-01-01

    通过浮选实验研究了两种不同结构的有机抑制剂古尔胶和鞣酸以及这两种药剂与乙基黄药不同添加顺序对方铅矿、黄铜矿及黄铁矿浮选行为的影响。当先加入古尔胶时,古尔胶对三种硫化矿抑制作用较强;而古尔胶后于乙基黄药加入时,古尔胶对三种硫化矿的抑制作用明显减弱。鞣酸与乙基黄药不同的添加顺序不影响鞣酸对黄铁矿和方铅矿的抑制作用。紫外光谱研究表明,古尔胶对乙基黄药在三种硫化矿表面吸附没有影响,而鞣酸能够阻碍乙基黄药在硫化矿表面吸附。红外光谱研究表明,鞣酸通过化学作用吸附在方铅矿表面,因此能够抑制吸附了乙基黄药的硫化矿。%The effects of two types of organic depressants, guar gum and tannic acid, on the flotation of galena, chalcopyrite and pyrite were investigated using micro-flotation tests, and different addition orders of the two reagents and ethyl xanthate were also stud-ied. When guar gum is added first, its depression effect on sulfides is considerable;but when ethyl xanthate is added first, guar gum has little depression effect on sulfide flotation. Tannic acid depresses pyrite and galena whatever addition order of ethyl xanthate. The interaction between guar gum or tannic acid and ethyl xanthate on the sulfide surface was studied by UV spectroscopy. It is indicated that guar gum has no impact on the adsorption of ethyl xanthate on the sulfide surface, while tannic acid can prevent the adsorption of ethyl xanthate. Infrared spectroscopy analysis suggests that tannic acid adsorbs on the galena surface by chemical action, which is the reason that tannic acid can depress sulfides adsorbing ethyl xanthate.

  10. On the Analysis of the Moessbauer Spectra of the Rust Converted by Tannic and Phosphoric Acids

    Energy Technology Data Exchange (ETDEWEB)

    Barrero, C. A. [Universidad de Antioquia, Grupo de Estado Solido, Instituto de Fisica (Colombia); Rios, J. F. [Universidad de Antioquia, Grupo de Corrosion y Proteccion, Facultad de Ingenierias (Colombia); Morales, A. L. [Universidad de Antioquia, Grupo de Estado Solido, Instituto de Fisica (Colombia); Bohorquez, A.; Perez-Alcazar, G. [Universidad del Valle, Grupo de Metalurgia Fisica y Transiciones de Fase, Departamento de Fisica (Colombia)

    2003-06-15

    In previous work, we reported results on the action of rust converters based on a mixture of tannic and phosphoric acids, upon the rust formed on mild steel coupons. There, the rust before and after the application of converters were characterized by room-temperature Moessbauer spectroscopy, among other techniques. The present work is an extension of this one, and additional MS at 77 K, 130 K and 300 K for some samples are presented. Special emphasis is given to the methodology of analysis. Our results confirm previous findings that an important portion of the magnetite remains without conversion. New information was also derived: (i) the converters seem to affect more the magnetite octahedral (B) than the tetrahedral (A) sites; (ii) among the magnetite B sites, the Fe{sup 2+} is the most affected; (iii) at least 31% of magnetic goethite at 77 K is transformed by the converter; and (iv) the presence of an additional phase identified as ferrous phosphate, could be resolved unambiguously only at these lower temperatures.

  11. Adsorption removal of tannic acid from aqueous solution by polyaniline: Analysis of operating parameters and mechanism.

    Science.gov (United States)

    Sun, Chencheng; Xiong, Bowen; Pan, Yang; Cui, Hao

    2017-02-01

    Polyaniline (PANI) prepared by chemical oxidation was studied for adsorption removal of tannic acid (TA) from aqueous solution. Batch adsorption studies were carried out under different adsorbent dosages, pH, ionic strength, initial TA concentration and coexisting anions. Solution pH had an important impact on TA adsorption onto PANI with optimal removal in the pH range of 8-11. TA adsorption on PANI at three ionic strength levels (0.02, 0.2 and 2molL(-1) NaCl) could be well described by Langmuir model (monolayer adsorption process) and the maximum adsorption capacity was 230, 223 and 1023mgg(-1), respectively. Kinetic data showed that TA adsorption on PANI fitted well with pseudo-second-order model (controlled by chemical process). Among the coexisting anions tested, PO4(3-) significantly inhibited TA adsorption due to the enhancement of repulsive interaction. Continuous flow adsorption studies indicated good flexibility and adaptability of the PANI adsorbent under different flow rates and influent TA concentrations. The mechanism controlling TA adsorption onto PANI under different operating conditions was analyzed with the combination of electrostatic interactions, hydrogen bonding, π-π interactions and Van der Waals interactions. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Pickering Emulsion Gels Prepared by Hydrogen-Bonded Zein/Tannic Acid Complex Colloidal Particles.

    Science.gov (United States)

    Zou, Yuan; Guo, Jian; Yin, Shou-Wei; Wang, Jin-Mei; Yang, Xiao-Quan

    2015-08-26

    Food-grade colloidal particles and complexes, which are formed via modulation of the noncovalent interactions between macromolecules and natural small molecules, can be developed as novel functional ingredients in a safe and sustainable way. For this study was prepared a novel zein/tannic acid (TA) complex colloidal particle (ZTP) based on the hydrogen-bonding interaction between zein and TA in aqueous ethanol solution by using a simple antisolvent approach. Pickering emulsion gels with high oil volume fraction (φ(oil) > 50%) were successfully fabricated via one-step homogenization. Circular dichroism (CD) and small-angle X-ray scattering (SAXS) measurements, which were used to characterize the structure of zein/TA complexes in ethanol solution, clearly showed that TA binding generated a conformational change of zein without altering their supramolecular structure at pH 5.0 and intermediate TA concentrations. Consequently, the resultant ZTP had tuned near neutral wettability (θ(ow) ∼ 86°) and enhanced interfacial reactivity, but without significantly decreased surface charge. These allowed the ZTP to stabilize the oil droplets and further triggered cross-linking to form a continuous network among and around the oil droplets and protein particles, leading to the formation of stable Pickering emulsion gels. Layer-by-layer (LbL) interfacial architecture on the oil-water surface of the droplets was observed, which implied a possibility to fabricate hierarchical interface microstructure via modulation of the noncovalent interaction between hydrophobic protein and natural polyphenol.

  13. Effects of tannic acid on trypsin and leucine aminopeptidase activities in gypsy moth larval midgut

    Directory of Open Access Journals (Sweden)

    Mrdaković Marija

    2013-01-01

    Full Text Available The effects of allelochemical stress on genetic variations in the specific activities of gypsy moth digestive enzymes (trypsin and leucine aminopeptidase and relative midgut mass (indirect measure of food consumption, as well as variability in their plasticity, were investigated in fifth instar gypsy moths originating from two populations with different trophic adaptations (oak and locust-tree forests. Thirty-two full-sib families from the Quercus population and twenty-six full-sib families from the Robinia population were reared on an artificial diet with or without supplementation with tannic acid. Between population differences were observed as higher average specific activity of trypsin and relative midgut mass in larvae from the Robinia population. Significant broad-sense heritabilities were observed for the specific activity of trypsin in the control state, and for specific activity of leucine aminopeptidase in a stressful environment. Significantly lower heritability for relative midgut mass was recorded in larvae from the Robinia population reared under stressful conditions. Significant variability of trypsin plasticity in larvae from both populations and significant variability of leucine aminopeptidase plasticity in larvae from the Robinia population point to the potential for the evolution of enzyme adaptive plastic responses to the presence of stressor. Non-significant across-environment genetic correlations do not represent a constraint for the evolution of enzyme plasticity. [Projekat Ministarstva nauke Republike Srbije, br. 173027

  14. Formulation for Oral Delivery of Lactoferrin Based on Bovine Serum Albumin and Tannic Acid Multilayer Microcapsules

    Science.gov (United States)

    Kilic, Ece; Novoselova, Marina V.; Lim, Su Hui; Pyataev, Nikolay A.; Pinyaev, Sergey I.; Kulikov, Oleg A.; Sindeeva, Olga A.; Mayorova, Oksana A.; Murney, Regan; Antipina, Maria N.; Haigh, Brendan; Sukhorukov, Gleb B.; Kiryukhin, Maxim V.

    2017-03-01

    Lactoferrin (Lf) has considerable potential as a functional ingredient in food, cosmetic and pharmaceutical applications. However, the bioavailability of Lf is limited as it is susceptible to digestive enzymes in gastrointestinal tract. The shells comprising alternate layers of bovine serum albumin (BSA) and tannic acid (TA) were tested as Lf encapsulation system for oral administration. Lf absorption by freshly prepared porous 3 μm CaCO3 particles followed by Layer-by-Layer assembly of the BSA-TA shells and dissolution of the CaCO3 cores was suggested as the most efficient and harmless Lf loading method. The microcapsules showed high stability in gastric conditions and effectively protected encapsulated proteins from digestion. Protective efficiency was found to be 76 ± 6% and 85 ± 2%, for (BSA-TA)4 and (BSA-TA)8 shells, respectively. The transit of Lf along the gastrointestinal tract (GIT) of mice was followed in vivo and ex vivo using NIR luminescence. We have demonstrated that microcapsules released Lf in small intestine allowing 6.5 times higher concentration than in control group dosed with the same amount of free Lf. Significant amounts of Lf released from microcapsules were then absorbed into bloodstream and accumulated in liver. Suggested encapsulation system has a great potential for functional foods providing lactoferrin.

  15. Boron removal by a composite sorbent: Polyethylenimine/tannic acid derivative immobilized in alginate hydrogel beads.

    Science.gov (United States)

    Bertagnolli, Caroline; Grishin, Andrey; Vincent, Thierry; Guibal, Eric

    2017-03-21

    A novel composite material was prepared by the grafting of tannic acid on polyethylenimine (PEI), which allows an efficient sorption of boron (sorption capacity close to 0.89 mmol B g(-1)). The encapsulation of this chelating sorbent (finely crushed) facilitates its use (readily solid/liquid separation, use in fixed-bed columns) at the expense of a loss in sorption capacity (proportionally decreased by the introduction of alginate having poor efficiency for boron uptake). Sorption isotherms are modeled using the Langmuir equation, while the kinetic profiles are presented a good fit by pseudo-second order rate equation. In addition, the encapsulating matrix introduces supplementary resistance to intraparticle diffusion, especially when the resin is dried without control: freeze-drying partially limits this effect. The stability (at long-term storage) of the sorbent is improved when the sorbent is stored under nitrogen atmosphere. The presence of an excess of NaCl was investigated. The degradation of the hydrogel (by ion-exchange of Ca(II) with Na(I)) leads to a decrease in the sorption performance of composite material but the action of Ca(II) ions in the solutions re-stabilizes the hydrogel.

  16. Tannic acid and saponin for removing arsenic from brownfield soils: Mobilization, distribution and speciation.

    Science.gov (United States)

    Gusiatin, Zygmunt Mariusz

    2014-04-01

    Plant biosurfactants were used for the first time to remove As and co-existing metals from brownfield soils. Tannic acid (TA), a polyphenol, and saponin (SAP), a glycoside were tested. The soil washing experiments were performed in batch conditions at constant biosurfactant concentration (3%). Both biosurfactants differed in natural pH, surface tension, critical micelle concentration and content of functional groups. After a single washing, TA (pH 3.44) more efficiently mobilized As than SAP (pH 5.44). When both biosurfactants were used at the same pH (SAP adjusted to 3.44), arsenic mobilization was improved by triple washing. The process efficiency for TA and SAP was similar, and depending on the soil sample, ranged between 50%-64%. Arsenic mobilization by TA and SAP resulted mainly from decomposition of Fe arsenates, followed by Fe(3+) complexation with biosurfactants. Arsenic was efficiently released from reducible and partially from residual fractions. In all soils, As(V) was almost completely removed, whereas content of As(III) was decreased by 37%-73%. SAP and TA might be used potentially to remove As from contaminated soils. Copyright © 2014 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  17. Resonance Rayleigh scattering technique for simple and sensitive analysis of tannic acid with carbon dots

    Science.gov (United States)

    Shi, Ying; Yang, Liu; Zhu, Jinghui; Yang, Jidong; Liu, Shaopu; Qiao, Man; Duan, Ruilin; Hu, Xiaoli

    2017-02-01

    Carbon dots (CDs) are raising a substantial amount of attention owing to their many unique and novel physicochemical properties. Herein one-pot synthesized CDs, to the best of our knowledge, were first served as the robust nanoprobe for detection tannic acid (TA) based on resonance Rayleigh scattering technique. The as-prepared CDs can combine with TA via hydrogen bond, resulting in remarkable enhancement of scattering signal with no changes in the fluorescence of CDs. Therefore, a novel protocol for TA determination was established and this strategy allowed quantitative detection of TA in the linear range of 0.2-10.0 μmol L- 1 with an excellent detection limit of 9.0 nmol L- 1. Moreover, the CDs based nanoprobe can be applied to the determination of TA in water sample with satisfactory results. Our study can potentially influence our current views on CDs and particularly impressive and offers new insights into application of CDs beyond the traditional understanding of CDs.

  18. Bioinspired tannic acid-copper complexes as selective coating for nanofiltration membranes

    KAUST Repository

    Chakrabarty, Tina

    2017-04-27

    Bio-polyphenols that are present in tea, date fruits, chockolate and many other plants have been recognized as scaffold material for the manufacture of composite filtration membranes. These phenolic biomolecules possess abundant gallol (1,2,3-trihydroxyphenyl) and catechol (1,2-dihydroxyphenyl) functional groups, which allow the spontaneous formation of a thin polymerized layer at the right pH conditions. Here, we report a facile and cost-effective method to coat porous membranes via the complexation of tannic acid (TA) and cupric acetate (mono hydrate) through co-deposition. The modified membranes were investigated by XPS, ATR/FTIR, water contact angle, SEM and water permeance for a structural and morphological analysis. The obtained results reveal that the modified membranes with TA and cupric acetate (CuII) developed a thin skin layer, which showed excellent hydrophilicity with good water permeance. These membranes were tested with different molecular weight polyethylene glycols (PEG) in aqueous solution; the MWCO was around 600 Daltons.

  19. Tannic acid alleviates lead acetate-induced neurochemical perturbations in rat brain.

    Science.gov (United States)

    Ashafaq, Mohammad; Tabassum, Heena; Vishnoi, Shruti; Salman, Mohd; Raisuddin, Sheikh; Parvez, Suhel

    2016-03-23

    Oxidative stress has been projected as a promising mechanism involved in lead exposure. The lead predisposition catalyzes oxidative reactions and generates reactive oxygen species. The present study was carried out to investigate the effect of oral administration of tannic acid (TA) on behavioral deficit, antioxidative deterioration induced by lead acetate (LA) exposure on experimental rat brain. Male Wistar rats were treated with 50mg/kg body weight of LA and TA for three times a week for two weeks. Our data showed LA-induced profound elevation of ROS production and oxidative stress, as evidenced by increased levels of oxidative stress markers such as lipid peroxidation and protein carbonyl observed in LA treated rats, whereas significant depletion in the activity of non-enzymatic antioxidants, enzymatic antioxidants, neurotoxicity biomarker and histological changes were observed in LA treated rat brain. However, TA administration restored antioxidant status of brain significantly when compared to control. Our results demonstrate that TA exhibits potent antioxidant properties and suppresses oxidative damages in rat brain induced by LA treatment. These findings were further supported by the neurotoxicity biomarker and histopathological findings in the brain tissue showed that TA protected tissue from deleterious effects of LA exposure. It is concluded, these data suggest that LA induces oxidative stress and supplementation of TA has a powerful antioxidant effect, and it protected rat brain from poisonous effect of LA exposure in experimental rat.

  20. Increased adhesion between neutral lipid bilayers: interbilayer bridges formed by tannic acid.

    Science.gov (United States)

    Simon, S A; Disalvo, E A; Gawrisch, K; Borovyagin, V; Toone, E; Schiffman, S S; Needham, D; McIntosh, T J

    1994-06-01

    Tannic acid (TA) is a naturally occurring polyphenolic compound that aggregates membranes and neutral phosolipid vesicles and precipitates many proteins. This study analyzes TA binding to lipid membranes and the ensuing aggregation. The optical density of dispersions of phosphatidylcholine (PC) vesicles increased upon the addition of TA and electron micrographs showed that TA caused the vesicles to aggregate and form stacks of tightly packed disks. Solution calorimetry showed that TA bound to PC bilayers with a molar binding enthalpy of -8.3 kcal/mol and zeta potential measurements revealed that TA imparted a small negative charge to PC vesicles. Monolayer studies showed that TA bound to PC with a dissociation constant of 1.5 microM and reduced the dipole potential by up to 250 mV. Both the increase in optical density and decrease in dipole potential produced by TA could be reversed by the addition of polyvinylpyrrolidone, a compound that chelates TA by providing H-bond acceptor groups. NMR, micropipette aspiration, and x-ray diffraction experiments showed that TA incorporated into liquid crystalline PC membranes, increasing the area per lipid molecule and decreasing the bilayer thickness by 2 to 4%. 2H-NMR quadrupole splitting measurements also showed that TA associated with a PC molecule for times much less than 10(-4) s. In gel phase bilayers, TA caused the hydrocarbon chains from apposing monolayers to fully interdigitate. X-ray diffraction measurements of both gel and liquid crystalline dispersions showed that TA, at a critical concentration of about 1 mM, reduced the fluid spacing between adjacent bilayers by 8-10 A. These data place severe constraints on how TA can pack between adjacent bilayers and cause vesicles to adhere. We conclude that TA promotes vesicle aggregation by reducing the fluid spacing between bilayers by the formation of transient interbilayer bridges by inserting its digallic acid residues into the interfacial regions of adjacent bilayers

  1. 丹宁酸对糜蛋白酶活性的影响%Inhibition of Tannic Acid on Chymotrypsin

    Institute of Scientific and Technical Information of China (English)

    赵军

    2013-01-01

    Objective To study the inhibition of tannic acid (TA) on enzyme activity of chymotrypsin. Methods Activity of chymotrypsin was determined with benzyl-L-tyrosine ethyl ester as the substrate, Km and apparent Km values of chymotrypsin were calculated with or without TA existence. Results The affinity between BTEE and chymotrypsin did not change with TA in the substrate, while the affinity changed when TA was added into enzyme preparation. The value of Km was 0.037mmol/L for chymotrypsin. The inhibition type was anti-competitive inhibition. Conculsion The enzymatic activity of chymotrypsin is inhibited by TA. The inhibition type is anti-competitive inhibition.%  目的研究丹宁酸(TA)对糜蛋白酶(chymotrypsin)活性的影响。方法应用苯甲酰-L-酪氨酸乙酯(BTEE)为底物测定糜蛋白酶的活性,根据Lineweaver Burk方程计算米氏常数Km,判断TA对糜蛋白酶的抑制类型。结果将TA加入底物,测酶液活性时,TA对糜蛋白酶无抑制作用;将不同浓度TA加入酶液中,随着TA浓度升高,糜蛋白酶活性降低,说明此时TA对糜蛋白酶有抑制作用;Lineweaver Burk方程和双倒数作图,表明其抑制类型为反竞争抑制。结论丹宁酸对糜蛋白酶有抑制作用,其抑制类型为反竞争抑制。

  2. Multilayer Capsules of Bovine Serum Albumin and Tannic Acid for Controlled Release by Enzymatic Degradation.

    Science.gov (United States)

    Lomova, Maria V; Brichkina, Anna I; Kiryukhin, Maxim V; Vasina, Elena N; Pavlov, Anton M; Gorin, Dmitry A; Sukhorukov, Gleb B; Antipina, Maria N

    2015-06-10

    With the purpose to replace expensive and significantly cytotoxic positively charged polypeptides in biodegradable capsules formed via Layer-by-Layer (LbL) assembly, multilayers of bovine serum albumin (BSA) and tannic acid (TA) are obtained and employed for encapsulation and release of model drugs with different solubility in water: hydrophilic-tetramethylrhodamine-isothiocyanate-labeled BSA (TRITC-BSA) and hydrophobic 3,4,9,10-tetra-(hectoxy-carbonyl)-perylene (THCP). Hydrogen bonding is proposed to be predominant within thus formed BSA/TA films. The TRITC-BSA-loaded capsules comprising 6 bilayers of the protein and polyphenol are benchmarked against the shells composed of dextran sulfate (DS) and poly-l-arginine (PARG) on degradability by two proteolytic enzymes with different cleavage site specificity (i.e., α-chymotrypsin and trypsin) and toxicity for murine RAW264.7 macrophage cells. Capsules of both types possess low cytotoxicity taken at concentrations equal or below 50 capsules per cell, and evident susceptibility to α-chymotrypsin resulted in release of TRITC-BSA. While the BSA/TA-based capsules clearly display resistance to treatment with trypsin, the assemblies of DS/PARG extensively degrade. Successful encapsulation of THCP in the TRITC-BSA/TA/BSA multilayer is confirmed, and the release of the model drug is observed in response to treatment with α-chymotrypsin. The thickness, surface morphology, and enzyme-catalyzed degradation process of the BSA/TA-based films are investigated on a planar multilayer comprising 40 bilayers of the protein and polyphenol deposited on a silicon wafer. The developed BSA/TA-based capsules with a protease-specific degradation mechanism are proposed to find applications in personal care, pharmacology, and the development of drug delivery systems including those intravenous injectable and having site-specific release capability.

  3. Mitigated calcification of glutaraldehyde-fixed bovine pericardium by tannic acid in rats

    Institute of Scientific and Technical Information of China (English)

    WANG De; JIANG Hong; LI Jun; ZHOU Jian-ye; HU Sheng-shou

    2008-01-01

    Background Bioprosthetic heart valves derived from glutaraldehyde (Glut)-fixed xenografts have been widely used to replace diseased cardiac valves.However,calcification and degeneration are common following their implantation.Inflammation is closely associated with calcification of Glut-fixed xenografts via macrophage infiltration.Tannic acid (TA)possesses anti-inflammatory effects.This study was designed to investigate the anti-calcification of TA treatment on the Glut-fixed bovine pericardium (BP) in a rat subdermal model.Methods Fresh BP was divided into two groups (10 in each group) and separately subjected to different fixation procedures as follows:(1) Glut group:fixation with 0.6% Glut alone;(2) Glut/TA group:fixation with 0.6% Glut and subsequent 0.3% TA.Then the BP samples were subdermally implanted in juvenile male Sprague-Dawley rats and explanted 21 days after implantation.Each explanted BP sample was divided into three parts for calcium content analysis,von Kossa's staining and immunohistochemical staining,and reverse transcription-polymerase chain reaction study.Results The data from quantitative calcium analysis and von Kossa's staining showed that Glut-fixed BP developed significantly more calcification than Glut/TA-fixed BP ((90.3±32.5) mg/g dry weight vs (6.4±1.3) mg/g dry tissue,P<0.01).Immunostaining demonstrated lower matrix metalloproteinase-9 and tenascin-C expression as well as macrophage infiltration into Glut/TA-fixed BP than in its Glut-fixed counterpart (P<0.01 for all).Additionally,the reverse transcription-polymerase chain reaction study showed that higher levels of expression of matrix metalloproteinase-9 and tenascin-C mRNA occurred within Glut-fixed BP than within the Glut/TA-flxed ones (P<0.01 for all).Conclusion TA exerts excellent anti-calcification effects on Glut-fixed BP via inhibiting macrophage infiltration and expression of matrix metalloproteinase-9 and tenascin-C.

  4. A facile and effective immobilization of glucose oxidase on tannic acid modified CoFe2O4 magnetic nanoparticles.

    Science.gov (United States)

    Altun, Seher; Çakıroğlu, Bekir; Özacar, Münteha; Özacar, Mahmut

    2015-12-01

    This article presents a study of glucose oxidase (GOx) immobilization by employing tannic acid (TA) modified-CoFe2O4 (CFO) magnetic nanoparticles which demonstrates novel aspect for enzyme immobilization. By using the strong protein and tannic acid binding, GOx immobilization was carried out via physical adsorption in a simpler way compared with the other immobilization methods which require various chemicals and complicated procedures which is difficult, expensive, time-consuming, and destructive to the enzyme structure. CFO was synthesized by hydrothermal synthesis and modified with TA to immobilize GOx. The immobilized GOx demonstrated maximum catalytic activity at pH 6.5 and 45 °C. The samples were characterized by vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential, and fourier transform infrared spectroscopy (FTIR), all of which confirm the surface modification of CFO and GOx immobilization. Also, field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD) were performed to demonstrate the surface morphology and chemical structure of samples. According to the Lineweaver-Burk plot, GOx possessed lower affinity to glucose after immobilization, and the Michelis-Menten constant (KM) of immobilized and free GOx were found to be 50.05 mM and 28.00 mM, respectively. The immobilized GOx showed excellent reusability, and even after 8 consecutive activity assay runs, the immobilized GOx maintained ca. 60% of its initial activity.

  5. Tannic acid is a natural β-secretase inhibitor that prevents cognitive impairment and mitigates Alzheimer-like pathology in transgenic mice.

    Science.gov (United States)

    Mori, Takashi; Rezai-Zadeh, Kavon; Koyama, Naoki; Arendash, Gary W; Yamaguchi, Haruyasu; Kakuda, Nobuto; Horikoshi-Sakuraba, Yuko; Tan, Jun; Town, Terrence

    2012-02-24

    Amyloid precursor protein (APP) proteolysis is essential for production of amyloid-β (Aβ) peptides that form β-amyloid plaques in brains of Alzheimer disease (AD) patients. Recent focus has been directed toward a group of naturally occurring anti-amyloidogenic polyphenols known as flavonoids. We orally administered the flavonoid tannic acid (TA) to the transgenic PSAPP mouse model of cerebral amyloidosis (bearing mutant human APP and presenilin-1 transgenes) and evaluated cognitive function and AD-like pathology. Consumption of TA for 6 months prevented transgene-associated behavioral impairment including hyperactivity, decreased object recognition, and defective spatial reference memory, but did not alter nontransgenic mouse behavior. Accordingly, brain parenchymal and cerebral vascular β-amyloid deposits and abundance of various Aβ species including oligomers were mitigated in TA-treated PSAPP mice. These effects occurred with decreased cleavage of the β-carboxyl-terminal APP fragment, lowered soluble APP-β production, reduced β-site APP cleaving enzyme 1 protein stability and activity, and attenuated neuroinflammation. As in vitro validation, we treated well characterized mutant human APP-overexpressing murine neuron-like cells with TA and found significantly reduced Aβ production associated with less amyloidogenic APP proteolysis. Taken together, these results raise the possibility that dietary supplementation with TA may be prophylactic for AD by inhibiting β-secretase activity and neuroinflammation and thereby mitigating AD pathology.

  6. Natural xenobiotics to prevent cyanobacterial and algal growth in freshwater: contrasting efficacy of tannic acid, gallic acid, and gramine.

    Science.gov (United States)

    Laue, Pauline; Bährs, Hanno; Chakrabarti, Shumon; Steinberg, Christian E W

    2014-06-01

    Allelochemical action against planktonic phototrophs is one central issue in freshwater ecology and quality management. To determine some basic mechanisms of this toxic action, we exposed the coccal green alga, Desmodesmus armatus, and the coccal cyanobacterium, Microcystis aeruginosa, in a batch culture well-supplied with carbon dioxide to increasing concentrations of the polyphenols tannic acid and gallic acid and the alkaloid gramine. The phototrophs were checked after 2d and at the end of the culture for biomass-based growth rates, cell volume, maximum quantum yield of photosystem II (ΦPSIImax), chlorophyll a content (chla) after 2d and at the end of the culture, and lipid peroxidation only at the end of the culture. During the culture, the pH rose from 7.64 to 10.95, a pH characteristic of eutrophic freshwater bodies during nuisance algal blooms. All xenobiotics reduced the growth rate, ΦPSIImax, and chla during the first 2d with M. aeruginosa being more sensitive to the polyphenols than D. armatus. The efficacy of the polyphenols declined with increasing pH, indicating potential polymerization and corresponding reduced bioavailability of the polyphenols. In contrast to the polyphenols, gramine increased its toxic action over time, independent of the prevailing pH. All exposures caused slight to severe lipid peroxidation (LPO) in the phototrophs. Hence, one mechanism of growth inhibition may be oxidative stress-mediated reduction in photosynthesis. The presented results suggest that in successful field trials with leachate, the prevailing environmental conditions may inactivate polyphenols and xenobiotics other than polyphenols may be more effective.

  7. Variability among strains of Aspergillus section Nigri with capacity to degrade tannic acid isolated from extreme environments.

    Science.gov (United States)

    Lara-Victoriano, F; Veana, F; Hernández-Castillo, F D; Aguilar, C N; Reyes-Valdés, M H; Rodríguez-Herrera, R

    2017-01-01

    Tannins are polyphenolic compounds that cause astringent flavor and turbidity in food. Tannase is an enzyme that catalyzes the hydrolysis of tannins and is used in food industry. This study was conducted to determine the genetic variability and the tannase alleles variation in fungal strains isolated from soil and plants at five extreme areas of Coahuila, México. Two screening assays under 1 and 20 % of tannic acid were performed, with the isolations. In these assays, it was possible to identify 756 and 128 fungal strains, respectively. The major fungal variability was observed in "Cuatro Ciénegas" with 26 strains. The microorganisms were distributed in 11 groups, which correspond to Aspergillus section Nigri. AN7 and AN1 groups showed the major number of isolates from "Paila" and "Cuatro Ciénegas" locations, respectively. In the last location, the major diversity and specific richness were found. But in "Ojo Caliente," tannase allele conservations were observed.

  8. Adsorption of aluminum and lead from wastewater by chitosan-tannic acid modified biopolymers: Isotherms, kinetics, thermodynamics and process mechanism.

    Science.gov (United States)

    Badawi, M A; Negm, N A; Abou Kana, M T H; Hefni, H H; Abdel Moneem, M M

    2017-06-01

    Chitosan was reacted by tannic acid to obtain three modified chitosan biopolymer. Their chemical structures were characterized by FTIR and elemental analysis. The prepared biopolymers were used to adsorb Al(III) and Pb(II) metal ions from industrial wastewater. The factors affecting the adsorption process were biosorbent amount, initial concentration of metal ion and pH of the medium. The adsorption efficiency increased considerably with the increase of the biosorbent amount and pH of the medium. The adsorption process of biosorbent on different metal ions was fitted by Freundlich adsorption model. The adsorption kinetics was followed Pseudo-second-order kinetic model. The adsorption process occurred according to diffusion mechanism which was confirmed by the interparticle diffusion model. The modified biopolymers were efficient biosorbents for removal of Pb(II) and Al(III) metal ions from the medium. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Corrosion inhibition of mild steel in 1 M HCl solution by henna extract: A comparative study of the inhibition by henna and its constituents (Lawsone, Gallic acid, {alpha}-D-Glucose and Tannic acid)

    Energy Technology Data Exchange (ETDEWEB)

    Ostovari, A. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)], E-mail: A.Ostovari@gmail.com; Hoseinieh, S.M.; Peikari, M. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Shadizadeh, S.R. [Petroleum Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of); Hashemi, S.J. [Technical Inspection Engineering Department, Petroleum University of Technology, Abadan (Iran, Islamic Republic of)

    2009-09-15

    The inhibitive action of henna extract (Lawsonia inermis) and its main constituents (lawsone, gallic acid, {alpha}-D-Glucose and tannic acid) on corrosion of mild steel in 1 M HCl solution was investigated through electrochemical techniques and surface analysis (SEM/EDS). Polarization measurements indicate that all the examined compounds act as a mixed inhibitor and inhibition efficiency increases with inhibitor concentration. Maximum inhibition efficiency (92.06%) is obtained at 1.2 g/l henna extract. Inhibition efficiency increases in the order: lawsone > henna extract > gallic acid > {alpha}-D-Glucose > tannic acid. Also, inhibition mechanism and thermodynamic parameters are discussed.

  10. Colorimetric method for the detection of melamine using in-situ formed silver nanoparticles via tannic acid

    Science.gov (United States)

    Alam, Md. Fazle; Laskar, Amaj Ahmed; Ahmed, Shahbaz; Shaida, Mohd. Azfar; Younus, Hina

    2017-08-01

    Melamine toxicity has recently attracted worldwide attention as it causes renal failure and the death of humans and animals. Therefore, developing a simple, fast and sensitive method for the routine detection of melamine is the need of the hour. Herein, we have developed a selective colorimetric method for the detection of melamine in milk samples based upon in-situ formation of silver nanoparticles (AgNPs) via tannic acid. The AgNPs thus formed were characterized by UV-Visible spectrophotometer, transmission electron microscope (TEM), zetasizer and dynamic light scattering (DLS). The AgNPs were used to detect melamine under in vitro condition and in raw milk spiked with melamine. Under optimal conditions, melamine could be selectively detected in vitro within the concentration range of 0.05-1.4 μM with a limit of detection (LOD) of 0.01 μM, which is lower than the strictest melamine safety requirement of 1 ppm. In spiked raw milk, the recovery percentage range was 99.5-106.5% for liquid milk and 98.5-105.5% for powdered milk. The present method shows extreme selectivity with no significant interference with other substances like urea, glucose, glycine, ascorbic acid etc. This assay method does not utilize organic cosolvents, enzymatic reactions, light sensitive dye molecules and sophisticated instrumentation, thereby overcoming some of the limitations of the other conventional methods.

  11. Solid Polymer Electrolytes Based on Functionalized Tannic Acids from Natural Resources for All-Solid-State Lithium-Ion Batteries.

    Science.gov (United States)

    Shim, Jimin; Bae, Ki Yoon; Kim, Hee Joong; Lee, Jin Hong; Kim, Dong-Gyun; Yoon, Woo Young; Lee, Jong-Chan

    2015-12-21

    Solid polymer electrolytes (SPEs) for all-solid-state lithium-ion batteries are prepared by simple one-pot polymerization induced by ultraviolet (UV) light using poly(ethylene glycol) methyl ether methacrylate (PEGMA) as an ion-conducting monomeric unit and tannic acid (TA)-based crosslinking agent and plasticizer. The crosslinking agent and plasticizer based on natural resources are obtained from the reaction of TA with glycidyl methacrylate and glycidyl poly(ethylene glycol), respectively. Dimensionally stable free-standing SPE having a large ionic conductivity of 5.6×10(-4)  Scm(-1) at room temperature can be obtained by the polymerization of PEGMA into P(PEGMA) with a very small amount (0.1 wt %) of the crosslinking agent and 2.0 wt % of the plasticizer. The ionic conductivity value of SPE with a crosslinked structure is one order of magnitude larger than that of linear P(PEGMA) in the waxy state.

  12. Improvement of interfacial interactions using natural polyphenol-inspired tannic acid-coated nanoclay enhancement of soy protein isolate biofilms

    Science.gov (United States)

    Wang, Zhong; Kang, Haijiao; Zhang, Wei; Zhang, Shifeng; Li, Jianzhang

    2017-04-01

    In this study, a novel and economic surface modification technique for montmorillonite (MMT) nanosheets, a biocompatible coupling cross-linking agent, was developed on an attempt at improving the interfacial adhesion with soy protein isolate (SPI) matrix. Inspired by natural polyphenol, the "green dip-coating" method using tannic acid (TA) to surface-modify MMT (TA@MMT). SPI nanocomposite films modified with MMT or TA@MMT, as well as the control ones, were prepared via the casting method. The TA layer was successfully coated on the MMT surface through the (FeIII) ions coordination chemistry and the synthetic samples were characterized by the Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), and transmission electron microscopy (TEM). The compatibility and interfacial interactions between modified MMT and SPI matrix were greatly enhanced by the TA-FeIII coating on the MMT surface. The mechanical properties, water resistance, and thermal stability of the resultant biofilm were increased accordingly. Compared with that of the unmodified SPI film, the tensile strength of the nanocomposite films modified by the green dip-coating was increased by 113.3%. These SPI-based nanocomposite films showed the favorable potential in terms of food packing applications due to their efficient barriers to water vapor and UV and/or visible light.

  13. Tannic acid binding of cell surfaces in normal, premalignant, and malignant squamous epithelium of the human uterine cervix.

    Science.gov (United States)

    Davina, J H; Lamers, G E; van Haelst, U J; Kenemans, P; Stadhouders, A M

    1984-01-01

    Alterations in tannic acid (TA) binding capacity of cell surface carbohydrates in normal, premalignant, and malignant squamous epithelium of the human uterine cervix have been studied using electron microscopic visualization in combination with microdensitometric evaluation. While in normal epithelium there is distinct binding in four to five cell layers of the deep intermediate zone, cells of carcinoma in situ and invasive cancer lesions lack TA binding. In moderate dysplasia an intermediate reacting pattern is found. Deep intermediate cells in areas bordering the carcinoma in situ lesions do not show any binding, although their ultrastructure cannot be distinguished from similar cells in normal tissue. The TA deposition within the deep intermediate zone is probably related to the presence here of glycoprotein-containing membrane-coating granules. The finding that TA binding discriminates between cells in normal squamous epithelium and morphologically normal cells in juxtaposition with lesional areas in premalignant and malignant epithelium opens the possibility for a more reliable cytologic diagnosis of cervical epithelial neoplasia.

  14. A Study on Tannic Acid-doped Polypyrrole Films on Gold Electrodes for Selective Electrochemical Detection of Dopamine

    Directory of Open Access Journals (Sweden)

    Shouzhuo Yao

    2005-04-01

    Full Text Available Tannic acid-doped polypyrrole (PPY/TA films have been grown on goldelectrodes for selective electrochemical detection of dopamine (DA. Electrochemicalquartz crystal microbalance (EQCM studies revealed that, in vivid contrast toperchlorate-doped polypyrrole films (PPY/ClO4-, the redox switching of PPY/TA filmsin aqueous solutions involved only cation transport if the solution pH was greater than3~4. The PPY/TA Au electrodes also exhibited attractive permselectivity forelectroactive cations, namely, effectively blocking the electrochemical reactions ofanionic ferricyanide and ascorbic acid (AA while well retaining the electrochemicalactivities of hexaammineruthenium (III and dopamine as cationic species. A 500 HzPPY/TA film could effectively block the redox current of up to 5.0 mM AA. Thecoexistence of ascorbic acid in the measurement solution notably enhanced the currentsignal for dopamine oxidation, due probably to the chemical regeneration of dopaminethrough an ascorbic acid-catalyzed reduction of the electro-oxidation product ofdopamine (EC’ mechanism, and the greatest amplification was found at an ascorbic acidconcentration of 1.0 mM. The differential pulse voltammetry peak current for DAoxidation was linear with DA concentration in the range of 0 to 10 μM, with sensitivityof 0.125 and 0.268 μA/μM, as well as lower detection limit of 2.0 and 0.3 μM in a PBSsolution without AA and with 1.0 mM coexisting AA, respectively.

  15. Effects of Tannic Acid on Lipid and Protein Oxidation, Color, and Volatiles of Raw and Cooked Chicken Breast Meat during Storage

    Directory of Open Access Journals (Sweden)

    Marwan Al-Hijazeen

    2016-06-01

    Full Text Available The objective of this study was to determine the effect of tannic acid (TA on the oxidative stability and the quality characteristics of ground chicken breast meat. Five treatments including (1 control (none added, (2 2.5 ppm TA, (3 5 ppm TA, (4 10 ppm TA, and (5 5 ppm butylated hydroxyanisole (BHA were added to boneless, skinless ground chicken breast meat, and used for both raw and cooked meat studies. For the raw meat study, the ground chicken breast meat was packaged in oxygen-permeable bags and stored at 4 °C for 7 days. For the cooked study, raw ground meat samples were vacuum-packaged in oxygen-impermeable vacuum bags, cooked in-bag to the internal temperature of 75 °C, re-packaged in oxygen-permeable bags, and then stored. Both raw and cooked meats were analyzed for lipid and protein oxidation, color, and volatiles (cooked meat only at 0, 3, and 7 days of storage. Raw meats with 10 ppm of TA added had significantly (p ≤ 0.05 lower lipid and protein oxidation than other treatments during storage. In addition, TA at 10 ppm level maintained the highest color a*- and L*-values during storage. Cooked chicken breast meat with 5 and 10 ppm TA added produced significantly (p ≤ 0.05 lower amounts of off-odor volatiles than other treatments. Among the volatile compounds, the amount of hexanal increased rapidly during storage for cooked meat. However, meats with 5 and 10 ppm TA added showed the lowest amount of hexanal and other aldehydes related to lipid oxidation, indicating a strong antioxidant effect of TA in cooked chicken breast meat. Furthermore, the differences in aldehydes among the treatments were bigger in cooked than in raw meat, indicating that the antioxidant effect of TA in cooked meat was greater than that in raw meat. Therefore, TA at >5 ppm can be used as a good natural preservative in cooked chicken meat to maintain its quality during storage.

  16. TRANSFORMATION AND ALLELOPATHY OF NATURAL DISSOLVED ORGANIC CARBON AND TANNIC ACID ARE AFFECTED BY SOLAR RADIATION AND BACTERIA(1).

    Science.gov (United States)

    Bauer, Nadine; Zwirnmann, Elke; Grossart, Hans-Peter; Hilt, Sabine

    2012-04-01

    The aim of this study was to test whether abiotic and biotic factors may affect allelopathic properties. Therefore, we investigated how solar radiation and bacteria influence allelopathic effects of the plant-derived, polyphenolic tannic acid (TA) on microalgae. Using a block design, lake water samples with and without TA were exposed to solar radiation or kept in darkness with or without bacteria for 3 weeks. Dissolved organic carbon (DOC), specific size fractions of DOC analyzed by chromatography-organic carbon detection (LC-OCD), and concentrations of total phenolic compounds (TPC) were measured to follow the fate of TA in lake water with natural DOC exposed to photolytic and microbial degradation. DOC and TPC decreased in dark-incubated lake water with TA and bacteria indicating microbial degradation. In contrast, exposure to solar radiation of lake water with TA and bacteria did not decrease DOC. Chromatographic analyses documented an accumulation of DOC mean size fraction designated as humic substances (HS) in sunlit water samples with TA. The recalcitrance of the humic fraction indicates that photolytic degradation may contribute to a DOC less available for bacterial degradation. Subsequent growth tests with Desmodesmus armatus (Chodat) E. Hegewald showed low but reproducible difference in algal growth with lower algal growth rate cultured in photolytically and microbially degraded TA in lake water than cultured in respective dark treatments. This finding highlights the importance of photolytic processes and microbial degradation influencing allelopathic effects and may explain the high potential of allelochemicals for structuring the phytoplankton community composition in naturally illuminated surface waters. © 2012 Phycological Society of America.

  17. Influence of gallic and tannic acids on enzymatic activity and growth ...

    African Journals Online (AJOL)

    SERVER

    2008-02-19

    Feb 19, 2008 ... This enzymatic technique is based on the diffusion of the enzymatic fraction on an ... various ester of the gallic acid and glucose (Hodek et al.,. 2002). .... peroxydase in potato tuber resistance to soft rot caused by Erwinia.

  18. 热镀锌钢板钼酸盐—单宁酸钝化研究%Study of molybdate-tannic acid passivation on galvanised steel

    Institute of Scientific and Technical Information of China (English)

    于斐; 刘光明; 杨柳

    2012-01-01

    A combined molybdate - tannic auid passivation treatment on galvanised steel is studied in this paper. Copper decoration drop testa indicated that the combined molybdate - tannic acid paasivated samples showed better corrosion resistance than that of samples treated separately by molybdate or lannic acid. The electrochemical behaviours of the passivated samples were investigated using potentiodynamic polarisation and electrochemical impendence spectra in 0. 5 mol L‐1 NaCl solution and showed corrosion current densities of 4.95 × 10‐5, 9.80 × 10‐5and 1.47 × 10‐4A . cm‐2 respectively. Electrochemical impendence spectra also indicated that molybdate - tannic passivated samples exhibited worse corrosion resistance than that of molybdate paasivated samples. The mechanism of molybdate - tannic acid passivation on galvanised steel is discussed in brief.%采用钼酸盐一单宁酸复合钝化工艺对热镀锌钢板进行了钝化处理.硫酸铜点滴实验表明,采用钼酸盐—单宁酸复合钝化的镀锌钢板的耐蚀性与单一钼酸盐钝化的耐蚀性相当.测试了镀锌钢板在0.5mol/L的NaCl溶液中钝化前后的极化曲线、电化学交流阻抗谱.结果表明:经钼酸盐、单宁酸、钼酸盐—单宁酸钝化的样品腐蚀电流密度分别为4.95×10-5、9.80×10-5和1.47×10-4A cm-2.电化学阻抗谱表明,单宁酸加入钼酸盐中,其钝化样品耐蚀性能有所下降.简要探讨了钼酸盐—单宁酸复合钝化机理.

  19. Removal of Cr(VI) from low-temperature micro-polluted surface water by tannic acid immobilized powdered activated carbon.

    Science.gov (United States)

    Li, Weiguang; Gong, Xujin; Li, Xin; Zhang, Duoying; Gong, Hainan

    2012-06-01

    In this study, food-grade tannic acid-immobilized powdered activated carbon (TA-PAC) was prepared, and adsorption of Cr(VI) (0.500 mg/L) onto TA-PAC as a function of pH, contact time, adsorption capacities and adsorption isotherms at 280 K was investigated. The results indicated that the immobilization process introduced abundant acid functional groups. The adsorption capacity of TA-PAC was found to be pH-dependent, and the optimal pH value was found to be 4.0. The equilibrium time was 240 min for TA-PAC. Adsorption data for total chromium were modeled using both two-parameter and three-parameter isotherm models. Freundlich and linear forms of three-parameter models yielded the best results for all of the data. Desorption studies of immobilized material suggested that the immobilization of food-grade tannic acid is steady. The adsorption mechanism of Cr(VI) on TA-PAC was assumed to be a comprehensive process consisting of surface reduction of Cr(VI), esterification between catechol and chromate, and ion exchange.

  20. Effects of dietary tannic acid and vaccination on the course of coccidiosis in experimentally challenged broiler chicken.

    Science.gov (United States)

    Mansoori, Behzad; Modirsanei, Mehrdad

    2012-06-08

    An experiment was carried out to assess the influence of tannic acid (TA) on integrity of the intestine in broiler chicks vaccinated against coccidiosis and challenged with the disease. In a 2 × 2 factorial design, the trial had five groups of 10 chickens each, including positive (group 2) and negative (group 1) controls. The chickens were kept on wood shavings and fed a commercial maize and soybean-based starter-grower diet. From day 1, groups 3 and 5 received TA (10 g kg(-1)) in their diet. On day 4, birds of groups 4 and 5 were vaccinated orally against coccidiosis with anti-coccidial vaccine, Livacox T™. Each dose of the vaccine contained 300-500 sporulated oocysts of each of Eimeria acervulina, Eimeria maxima and Eimeria tenella. On day 18, all experimental groups except for the negative (group 1) were challenged with 10-fold dose of Livacox T™ to produce a mild coccidiosis infection. Faecal samples of individual birds were collected on day 23, and the number of faecal oocysts was determined. d-Xylose absorption test was also carried out on all birds on day 23. Immediately after d-xylose absorption test, all birds were killed humanely and the intestinal tract was removed, weighed and examined for gross lesions. Results showed that negative (group 1) and positive controls (group 2) had the highest and lowest levels of plasma d-xylose post-ingestion of the substrate, respectively. Vaccination and/or feeding TA raised the level of plasma d-xylose in infected birds, although this was not significant for TA-fed birds. Vaccination reduced but TA increased the total number of oocysts per gram of faeces. Birds of groups 2-5 had distinct intestinal lesions when compared with group 1. However, vaccination prevented intestinal lesions. Relative weights of intestinal parts were the lowest in group 1 and the highest in group 2. Vaccination but not TA reduced the relative weights of intestinal parts in infected birds. It was concluded that dietary tannins may reduce

  1. Study of the adsorption of Cr(VI) by tannic acid immobilised powdered activated carbon from micro-polluted water in the presence of dissolved humic acid.

    Science.gov (United States)

    Gong, Xujin; Li, Weiguang; Wang, Ke; Hu, Jinhua

    2013-08-01

    The adsorption of Cr(VI) (0.500 mg/L) onto food-grade tannic-acid immobilised powdered activated carbon (TA-PAC) in the presence of dissolved humic acid (DHA) was investigated at 280 K as a function of pH, along with the adsorption capacities and the adsorption isotherms for chromium ions. The results showed that the presence of DHA improved the adsorption capacities of Cr(VI) and its reduction product (Cr(III)) over a wide pH range (4.0-8.0). The main mechanism for metal-DHA complexation in the Cr(VI) system was the reduction of Cr(VI) followed by complexation between Cr(III) and DHA. The Freundlich isotherms yielded the best fits to all data (R(2)=0.9951, qm=5.639 mg/g) in the presence of DHA. The adsorption mechanisms of Cr(VI) onto TA-PAC in the presence of DHA were summarized into three categories: (i) binding by anion adsorption, (ii) Cr(VI) reduction followed by Cr(III) adsorption, and (iii) adsorption of Cr(III)-DHA complexes.

  2. 单宁酸的体外抑菌作用及其影响因素%Antimicrobial Activity of Tannic Acid in Vitro and Its Influencing Factors

    Institute of Scientific and Technical Information of China (English)

    郑正男; 谭俊杰; 吴帅; 丁利君; 郑希

    2015-01-01

    研究了单宁酸在体外的抑菌作用及其影响因素.采用滤纸片法和琼脂二倍稀释法测定了食品体系中常见腐败菌的抗菌活性和最小抑菌浓度,并用琼脂比较法在食品体系中不同的pH、氯化钠浓度、蔗糖浓度、金属离子和有机酸的条件下,进行抗菌影响因素筛选.结果表明,单宁酸对金黄色葡萄球菌和藤黄微球菌有很好的抑菌活性,其最小抑菌浓度分别为0.39 mg/mL和0.09 mg/mL,单宁酸在酸性条件下,并同时与柠檬酸或乳酸协同作用下,可加强单宁酸对食品中腐败菌的抑菌效果;而食品中的氯化钠浓度、蔗糖浓度和金属离子对其抗菌效果都没有不利作用.因此,与常见食品防腐剂山梨酸钾相比,单宁酸的最低抑菌浓度比较低.%In this paper the antibacterial effect of tannin in vitro and its influencing factors are investiga-ted.The minimal inhibitory concentration is measured through the agar dilution,and the antimicrobial properties are screened by filter disc method in food system.By using agar-comparing method,various antibacterial factors in food system such as pH value,sodium chloride concentration,sucrose concentra-tion,metal ions and organic acids,on its bacteriostatic effect are screened.The results show that tannins have good antibacterial activities on Staphylococcus aureus and Micrococcus luteus,MIC of which is 0.39 mg/mL and 0.09 mg/mL respectively.Under the condition of acid,or under the synergism of citric acid and lactic acid,the antibacterial effects of tannic acid on food spoilage organisms increase;and the bac-teriostatic effects are stable for NaCl,sucrose and metal ion.Compared with potassium sorbate,it seems to have a better effect on food and the MIC of which is lower than potassium sorbate.Tannins with organic acid together are more conducive to the antibacterial activity,which have a wide pH range.With added salt and sugar food,tannins can weaken the use of salt or sugar,and be

  3. Antimicrobial spray nanocoating of supramolecular Fe(III)-tannic acid metal-organic coordination complex: applications to shoe insoles and fruits.

    Science.gov (United States)

    Park, Ji; Choi, Sohee; Moon, Hee; Seo, Hyelin; Kim, Ji; Hong, Seok-Pyo; Lee, Bong; Kang, Eunhye; Lee, Jinho; Ryu, Dong; Choi, Insung S

    2017-08-01

    Numerous coating strategies are available to control the surface properties and confer new properties to substrates for applications in energy, environment, biosystems, etc., but most have the intrinsic limitations in the practical setting: (1) highly specific interactions between coating materials and target surfaces are required for stable and durable coating; (2) the coating of bulk substrates, such as fruits, is time-consuming or is not achievable in the conventional solution-based coating. In this respect, material-independent and rapid coating strategies are highly demanded. We demonstrate spray-assisted nanocoating of supramolecular metal-organic complexes of tannic acid and ferric ions. The spray coating developed is material-independent and extremely rapid (coating of commodity goods, such as shoe insoles and fruits, in the controlled fashion. For example, the spray-coated mandarin oranges and strawberries show significantly prolonged post-harvest shelf-life, suggesting practical potential in edible coating of perishable produce.

  4. 单宁酸磷脂复合物的制备及其理化性质研究%Study on preparation and physic-chemical properties of tannic acid-phospholipid complex

    Institute of Scientific and Technical Information of China (English)

    吴春; 冯海波

    2015-01-01

    Preparation of tannic acid -phospholipid complex was studied using tannic acid and soybean lecithin as materials .The effects of reactive temperature , reactive time , con-centration of react-ants and the ratio of reactants on preparation were investigated using sin-gle factor experiment , the optimal reaction conditions were determined by orthogonal test , and the physic -chemical properties of tannic acid -phospholipid complex and solubility were examined .The optimized conditions were obtained as follows:the reactive temperature was 60 ℃;the reactive time was 1.5 h;the concentration of reactants was 4 mg/mL, and the ratio of tannic acid to phospholipid was 2∶1 .IR and UV spectroscopic analysis showed that tannic acid and phospholipids did not form a new compound but a kind of complex com-bine through intermolecular force .Compared with tannic acid , solubility in water redused , but the octanol solubility improved obviously .%以单宁酸和大豆卵磷脂为原料制备单宁酸磷脂复合物.以单宁酸与磷脂的复合率为评价标准,通过单因素实验考察反应温度、反应时间、反应物初始质量浓度和投料比例对复合率的影响,由正交试验得到最优条件.研究了单宁酸磷脂复合物的理化性质及溶解性能.结果表明,单宁酸磷脂复合物的最佳制备工艺为:以乙醇为反应溶剂,反应温度为60℃,反应时间为1.5 h,单宁酸质量浓度为4 mg/mL,投料质量比例为2∶1.红外光谱和紫外光谱分析表明,单宁酸与磷脂未形成新的化合物而是通过分子间作用力形成的复合物.与单宁酸相比,复合物在水中溶解度有所降低,但在正辛醇中溶解性有明显改善.

  5. Effects of gallnut tannic acid on Streptococcus mutans plaque biofilm formation: An in vitro study%五倍子单宁酸影响变异链球菌生物膜形成的体外研究

    Institute of Scientific and Technical Information of China (English)

    李娜; 赵春苗; 程小刚; 李经纬; 付建军; 王晓娟; 唐荣银; 余擎

    2013-01-01

    AIM: To observe the effects of gallnut tannic acid on Streptococcus mutans plaque biofilm forma- tion in Bioflux System. METHODS: Streptococcus mutans was incubated in the observation zone of Bioflux200 System for 30 min, then BHIS solution (control group) , BHIS containing 8mg/mL or 16mg/mL Gallnut tannic acid, BHIS solution containing 2 g/L chlorhexidine (positive control group) were added to the inlet respectively. The bacteria were continuously cultured under 0. 8 dyne shear force for 12 h. The biofilm formation was observed under confocal laser scanning microscope after staining with LIVE/DEAD ? BacLightTM Bacterial Viability Kit. RESULTS; Complete plaque biofilm was formed in the control group, and most bacteria was live. No biofilm formation was observed in the 2 gallnut tanic acid treatment groups, only a few of sparsely distributed live and dead bacteria could be found. In the chlorhexidine group, no plaque biofilm formation was observed and only scattered dead bacteria could be seen. CONCLUSION ; Gallnut tannic acid can inhibit the Streptococcus mutans biofilm formation under shear force.%目的:在微流体系统(Bioflux System)中观察五倍子单宁酸对变异链球菌生物膜形成的影响作用.方法:Bioflux200系统中接种复苏的变异链球菌至观察区,静置30 min后,分别在各进孔加入BHIS液(对照组)、含五倍子单宁酸终末浓度分为8 mg/mL(实验1组)、16 mg/mL(实验2组)的BHIS液及含2 g/L洗必泰的BHIS液(阳性对照组);然后在0.8 dyne剪切力作用下连续培养12h;活菌死菌荧光染色剂(LIVE/DEAD(R)BacLightTM)染色后在激光共聚焦扫描显微镜下观察各组生物膜的形成情况.结果:对照组形成了较完整的菌斑生物膜且视野内多为活菌;两种浓度五倍子单宁酸组均无菌斑生物膜形成,只可观察到少量散在的死菌和活菌;洗必泰组亦无菌斑生物膜的形成,且视野内基本为散在的死菌存在.结论:一定浓度五倍子单宁

  6. Effect of EDTA and Tannic Acid on the Removal of Cd, Ni, Pb and Cu from Artificially Contaminated Soil by Althaea rosea Cavan.

    Science.gov (United States)

    Cay, Seydahmet; Uyanik, Ahmet; Engin, Mehmet Soner; Kutbay, Hamdi Guray

    2015-01-01

    In this study an ornamental plant of Althaea rosea Cavan was investigated for its potential use in the removal of Cd, Ni, Pb and Cu from an artificially contaminated soil. Effect of two different chelating agents on the removal has also been studied by using EDTA (ethylenediaminetetracetic acid) and TA (tannic acid). Both EDTA and TA have led to higher heavy metal concentration in shoots and leaves compared to control plants. However EDTA is generally known as an effective agent in metal solubilisation of soil, in this study, TA was found more effective to induce metal accumulation in Althaea rosea Cavan under the studied conditions. In addition to this, EDTA is toxic to some species and restraining the growth of the plants. The higher BCF (Bio Concentration Factor) and TF (Translocation Factor) values obtained from stems and leaves by the effects of the chemical enhancers (EDTA and TA) show that Althaea rosea Cavan is a hyper accumulator for the studied metals and may be cultivated to clean the contaminated soils.

  7. Dietary tannic acid modulate sodium balance in root voles (Microtus oeconomus)%食物单宁酸对根田鼠(Microtus oeconomus)钠平衡的作用

    Institute of Scientific and Technical Information of China (English)

    李俊年; 陶双伦; 刘季科

    2008-01-01

    验证了单宁酸能引起植食性哺乳动物钠平衡的假设.在两种食物蛋白质水平条件下,测定了摄食含0%,3%和6%单宁酸食物的根田鼠的钠平衡和肾上腺肾小球的大小.结果表明,食物单宁酸能显著影响根田鼠的钠平衡,钠的丢失主要通过尿液.同时,单宁酸能显著影响试验个体的肾上腺肾小球的体积.初步研究显示,植食性哺乳动物对摄入的植物次生化合物的解毒引起机体钠平衡失调,而非植物次生化合物的消化抑制作用所致.%This tested the hypotheis that tannic acid can cause an imbalance of ma mmmalian hebivors.The sodium balance and the size of the zona glomerulosa of the adrenal gland was measured in root voles fed a diet containing either low or high proteins supplemented with 0, 3, or 6% of tannic acid. Relative areas of adrenal regions (zona glomerulosa, combined zona fasciculata and zona reticularis (ZFZR)) of voles fed diets containing 6% of tannic acid were increased by 9% and 7.8% for low and high protein groups, respectively, compared with those in animals fed the control diets. ZFZR/cortex of voles fed a low or high protein diet containing 3% of tannic acid were increased by 14.31% and 6.5%, respectively, as compared with those of control groups. The results indicate that addition of tannic acid to a diet can significantly induce sodium excretion mainly through urine in root voles, which may affect sodium homeostasis. These results also suggest that detoxification rather than inhibition of digestibility may primarily contribute to the sodium imbalance of mammalian herbivores that are ingesting plant secondary compounds.

  8. Dopamine functionalized tannic-acid-templated mesoporous silica nanoparticles as a new sorbent for the efficient removal of Cu2+ from aqueous solution

    Science.gov (United States)

    Gao, Junkai; Lei, Hao; Han, Zhi; Shi, Qian; Chen, Yan; Jiang, Yanjun

    2017-03-01

    A simple, environmentally friendly and cost-effective nonsurfactant template method was used to synthesize tannic-acid-templated mesoporous silica nanoparticles (TMSNs), and then dopamine functionalized TMSNs (Dop-TMSNs) which was synthesized by a facile and biomimetic coating strategy, was developed as a new sorbent for the removal of Cu2+ from aqueous solution. The Dop-TMSNs were thoroughly characterized by SEM, TEM, BET, FT-IR and TGA, and the effects of contact time, initial pH, K+ and Na+ concentrations, co-existing polyvalent metal ions and adsorption-desorption cycle times on the sorption capacity of Dop-TMSNs were studied. It was demonstrated that the maximum adsorption capacity of Cu2+ by Dop-TMSNs was 58.7 mg/g at pH 5.5, and the sorption reached equilibrium within 180 min. Moreover, the K+ and Na+ concentrations had a very slight influence on the sorption process and the adsorption capacity of the Dop-TMSNs still remained 89.2% after recycling for four times. All the results indicated that the Dop-TMSNs could be utilized as an excellent sorbent for the sequestration of Cu2+.

  9. Tannic acid- and natural organic matter-coated magnetite as green Fenton-like catalysts for the removal of water pollutants

    Science.gov (United States)

    Nadejde, C.; Neamtu, M.; Hodoroaba, V.-D.; Schneider, R. J.; Paul, A.; Ababei, G.; Panne, U.

    2015-12-01

    The use of magnetic materials as heterogeneous catalysts has attracted increasing attention in the last years since they proved to be promising candidates for water treatment. In the present study, two types of surface-modified magnetite (Fe3O4) nanoparticles, coated with non-hazardous naturally occurring agents—either tannic acid (TA) or dissolved natural organic matter—were evaluated as magnetic heterogeneous catalysts. Chemical synthesis (co-precipitation) was chosen to yield the nanocatalysts due to its well-established simplicity and efficiency. Subsequently, the properties of the final products were fully assessed by various characterization techniques. The catalytic activity in heterogeneous oxidation of aqueous solutions containing a model pollutant, Bisphenol A (BPA), was comparatively studied. The effect of operational parameters (catalyst loading, H2O2 dosage, and UV light irradiation) on the degradation performance of the oxidation process was investigated. The optimum experimental parameters were found to be 1.0 g/L of catalysts and 10 mM H2O2, under UV irradiation. The highest mineralization rates were observed for Fe3O4-TA catalyst. More than 80 % of BPA was removed after 30 min of reaction time under the specified experimental conditions. The obtained results showed that the two catalysts studied here are suitable candidates for the removal of pollutants in wastewaters by means of heterogeneous reaction using a green sustainable treatment method.

  10. Water treatment by H2O2 and/or UV affects carbon nanotube (CNT) properties and fate in water and tannic acid solution.

    Science.gov (United States)

    Czech, Bożena; Oleszczuk, Patryk; Wiącek, Agnieszka Ewa; Barczak, Mariusz

    2015-12-01

    The objective of the study was to estimate how water treatment (stimulation of real conditions) by H2O2 and/or UV affects carbon nanotube (CNT) properties and fate (stability/aggregation) in water and tannic acid solution. The processes studied had only a slight effect on SBET, porosity, and surface composition of CNTs. There was a change in the morphology of CNTs. After H2O2 and/or UV treatment, CNTs underwent shortening, opening up of their ends, and exfoliation. Treatment with H2O2 increased the content of oxygen in CNTs. A decrease was observed in the surface charge and in the mobility of CNTs, which caused an increase in their stability. UV irradiation of CNTs led to an increased incidence of defects that were manifested by both an increase of zeta potential and an increased mobility of CNT, whereas the presence of H2O2 during UV irradiation had only a slight effect on the parameters of the porous structure of nanotubes.

  11. Inhibition of NADPH-cytochrome P450 reductase by tannic acid in rat liver microsomes and primary hepatocytes: methodological artifacts and application to ischemia-reperfusion injury.

    Science.gov (United States)

    Pillai, Venkateswaran C; Mehvar, Reza

    2011-08-01

    Tannic acid (TA) inhibits nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase (CPR) activity, which is measured by reduction of cytochrome c, in rat liver microsomes (RLMs). In the current study, we noticed that TA directly reduces cytochrome c in the absence of microsomes, thus confounding the CPR activity assay. A method is presented that measures CPR activity in the presence of TA by subtracting the cytochrome c reduction in the absence of NADPH (TA effect) from that in the presence of NADPH (TA plus CPR effect). The method was used to determine the inhibitory effect of TA in RLMs, recombinant CPR enzyme, and primary hepatocytes. Additionally, application of TA in a study of role of CPR in a primary rat hepatocyte model of ischemia-reperfusion (IR) was investigated. TA showed concentration-dependent, complete inhibition of CPR with half maximal inhibitory concentration (IC(50) ) values of 58.2 μM in RLMs and 54.6 and 275 μM in primary rat hepatocytes in the absence and presence of serum in the medium, respectively. Additionally, inhibition of CPR by TA was associated with a significant reduction in reactive oxygen species and cell death after IR injury. These data may be useful in future studies using TA as an inhibitor of CPR in microsomes and primary hepatocytes.

  12. Single-Step Assembly of Multifunctional Poly(tannic acid)-Graphene Oxide Coating To Reduce Biofouling of Forward Osmosis Membranes.

    Science.gov (United States)

    Hegab, Hanaa M; ElMekawy, Ahmed; Barclay, Thomas G; Michelmore, Andrew; Zou, Linda; Saint, Christopher P; Ginic-Markovic, Milena

    2016-07-13

    Graphene oxide (GO) nanosheets have antibacterial properties that have been exploited as a biocidal agent used on desalination membrane surfaces in recent research. Nonetheless, improved strategies for efficient and stable attachment of GO nanosheets onto the membrane surface are still required for this idea to be commercially viable. To address this challenge, we adopted a novel, single-step surface modification approach using tannic acid cross-linked with polyethylene imine as a versatile platform to immobilize GO nanosheets to the surface of polyamide thin film composite forward osmosis (FO) membranes. An experimental design based on Taguchi's statistical method was applied to optimize the FO processing conditions in terms of water and reverse solute fluxes. Modified membranes were analyzed using water contact angle, adenosine triphosphate bioluminescence, total organic carbon, Fourier transform infrared spectroscopy, ζ potential, X-ray photoelectron spectroscopy, transmission electron microscopy, and atomic force microscopy. These results show that membranes were modified with a nanoscale (<10 nm), smooth, hydrophilic coating that, compared to pristine membranes, improved filtration and significantly mitigated biofouling by 33% due to its extraordinary, synergistic antibacterial properties (99.9%).

  13. Tannic acid- and natural organic matter-coated magnetite as green Fenton-like catalysts for the removal of water pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Nadejde, C., E-mail: claudianadejde@gmail.com; Neamtu, M., E-mail: mariana.neamtu@uaic.ro [‘Alexandru Ioan Cuza’ University, Interdisciplinary Research Department – Field Science (Romania); Hodoroaba, V.-D.; Schneider, R. J.; Paul, A. [BAM Federal Institute for Materials Research and Testing (Germany); Ababei, G. [National Institute of Research and Development for Technical Physics (Romania); Panne, U. [BAM Federal Institute for Materials Research and Testing (Germany)

    2015-12-15

    The use of magnetic materials as heterogeneous catalysts has attracted increasing attention in the last years since they proved to be promising candidates for water treatment. In the present study, two types of surface-modified magnetite (Fe{sub 3}O{sub 4}) nanoparticles, coated with non-hazardous naturally occurring agents—either tannic acid (TA) or dissolved natural organic matter—were evaluated as magnetic heterogeneous catalysts. Chemical synthesis (co-precipitation) was chosen to yield the nanocatalysts due to its well-established simplicity and efficiency. Subsequently, the properties of the final products were fully assessed by various characterization techniques. The catalytic activity in heterogeneous oxidation of aqueous solutions containing a model pollutant, Bisphenol A (BPA), was comparatively studied. The effect of operational parameters (catalyst loading, H{sub 2}O{sub 2} dosage, and UV light irradiation) on the degradation performance of the oxidation process was investigated. The optimum experimental parameters were found to be 1.0 g/L of catalysts and 10 mM H{sub 2}O{sub 2}, under UV irradiation. The highest mineralization rates were observed for Fe{sub 3}O{sub 4}-TA catalyst. More than 80 % of BPA was removed after 30 min of reaction time under the specified experimental conditions. The obtained results showed that the two catalysts studied here are suitable candidates for the removal of pollutants in wastewaters by means of heterogeneous reaction using a green sustainable treatment method.

  14. Efficacy of adding folic acid to foods.

    Science.gov (United States)

    Fajardo, Violeta; Varela-Moreiras, Gregorio

    2012-06-01

    In the past, food fortification along with nutritional education and the decrease in food costs relative to income have proven successful in eliminating common nutritional deficiencies. These deficiencies such as goiter, rickets, beriberi, and pellagra have been replaced with an entirely new set of "emergent deficiencies" that were not previously considered a problem [e.g., folate and neural tube defects (NTDs)]. In addition, the different nutrition surveys in so-called affluent countries have identified "shortfalls" of nutrients specific to various age groups and/or physiological status. Complex, multiple-etiology diseases, such as atherosclerosis, diabetes, cancer, and obesity have emerged. Food fortification has proven an effective tool for tackling nutritional deficiencies in populations; but today a more reasonable approach is to use food fortification as a means to support but not replace dietary improvement strategies (i. e. nutritional education campaigns). Folic acid (FA) is a potential relevant factor in the prevention of a number of pathologies. The evidence linking FA to NTD prevention led to the introduction of public health strategies to increase folate intakes: pharmacological supplementation, mandatory or voluntary fortification of staple foods with FA, and the advice to increase the intake of folate-rich foods. It is quite contradictory to observe that, regardless of these findings, there is only limited information on food folate and FA content. Data in Food Composition Tables and Databases are scarce or incomplete. Fortification of staple foods with FA has added difficulty to this task. Globally, the decision to fortify products is left up to individual food manufacturers. Voluntary fortification is a common practice in many countries. Therefore, the "worldwide map of vitamin fortification" may be analyzed. It is important to examine if fortification today really answers to vitamin requirements at different ages and/or physiological states. The

  15. A survey of a mistake of food poisoning caused by tannic acid iron%一起鞣酸铁误判食物中毒的调查报告

    Institute of Scientific and Technical Information of China (English)

    刘忠惠; 叶绿; 赛斌

    2013-01-01

    Objective An investigation of a misjudgment of food chemical reaction to be a food poison-ing was studied and the value of reference for clinicians and public health practitioners was suggested. Meth-ods Based on the on-site survey, the following experiment was practised: the sauerkrautsoup was made by mixing the similarly block of pickled cabbage and noodles, and was heated with pans made of different materi-als; the tea was made by boiling water and was put into different pans. Results Only the soup heated in wok became dark, which is because of the iron in the sauerkraut and the tannic acid in tea generating the tannin iron as precipitation, that made the lips, teeth, and tongue dark, and stomach feeling discomfort and having a burn-ing sensation. Conclusion This event was a mistake for a food poisoning which was actually a food chemical reaction caused by the tannic acid iron.%  目的对一起因食物化学反应误判为食物中毒的事件进行调查,以期对临床医师和公共卫生医师提供临床处理经验。方法根据事件现场调查,设计同等过程实验,将相同的酸菜和面块混合,用不同材质锅加热制成酸菜面块汤;把茶叶用开水泡成茶水,分别加入不同的锅内,进行实验室检验。结果用铁锅加热制作的汤颜色变黑,其他的不变色,即酸菜中的铁与茶叶中的鞣酸生成鞣酸铁沉淀,并导致人体口唇、牙齿、舌苔发黑,引起胃部不适和烧灼感。结论此次疑似食物中毒事件实质上是属于鞣酸铁引起的食物中毒误判。

  16. Decomposição fúngica de ácido tânico e outros compostos em efluente agroindustrial = Fungic decomposition of tannic acid and other compounds from agri-industrial effluent

    Directory of Open Access Journals (Sweden)

    Natalino Perovano Filho

    2011-04-01

    Full Text Available Durante o processamento da matéria-prima da indústria sucroalcooleira, gerase grande quantidade de efluentes com qualidades que impossibilitam seu lançamento em corpos de água sem o tratamento prévio. A biorremediação é usada para decompor resíduos orgânicos até um estado inócuo ou abaixo da concentração limite da legislação, tendo os fungos papel muito importante nessa estratégia por secretarem enzimas hidrolíticas. Neste trabalho, avaliou-se o comportamento de fungos isolados de resíduos da estação de tratamento de efluentes de uma indústria sucroalcooleira frente à degradação de fenóis como o ácido tânico e de outros compostos de efluentes agroindustriais suplementados com nutrientes específicos. Dentre diferentes isolados, aqueles identificados como Aspergillus sp.e Cladosporium sp. apresentaram as melhores taxas de produção de enzimas degradadoras de ácido tânico, como a lacase, por exemplo, enquanto Mucor sp. foi o que melhor removeu a Demanda Química de Oxigênio (DQO e o conteúdo de fenóis totais, seguido por Cladosporium sp., Phanerochaeta chrysosporium e Geotrichum candidum.During the processing of raw materials from the sugar-alcohol industry, large quantities of wastewater is produced, which is inappropriate to release into water bodies without previous suitable treatment. The bioremediation is used to decompose organic waste until an innocuous condition or to a concentration below the limit under legislation; moreover fungi have very important role in this strategy due to the secretion of hydrolytic enzymes. In the present study, we evaluated the behavior of fungi isolated from residuals of the waste treatment station from a sugar-alcohol industry in faceto the phenols degradation, as tannic acid and other compounds of agri-industrial wastewater supplemented with specific nutrients. Among different fungi, those identified as Aspergillus sp. and Cladosporium sp. presented the best rates of

  17. 鞣酸模板交联壳聚糖/凹凸棒粘土复合树脂的吸附性能%Adsorption Properties of Crosslinked Chitosan/Attapulgite Composite Resin with Tannic Acid as Template Molecule

    Institute of Scientific and Technical Information of China (English)

    吴洁; 张娟; 冯辉霞; 丁师杰; 许培

    2012-01-01

    以鞣酸(TA)为模板,采用乳化交联法制备了壳聚糖/凹凸棒粘土复合树脂(TA-CAR)。利用红外光谱(FT-IR)和扫描电镜(SEM)对树脂的结构和形态进行表征。结果表明,与非模板树脂相比,TA-CAR对TA的吸附量从185 mg/g提高到232 mg/g,且具有一定的吸附选择性,树脂的吸附等温线和动力学可以用Langmuir方程和伪二级动力学模型很好地拟合,TA-CAR较高的吸附能力归因于树脂中特异吸附位点的识别作用和表面吸附的协同作用。树脂的再生性能研究表明,凹土的加入不但提高了复合树脂的吸附量,而且显著改善了树脂的耐酸能力,可实现树脂的再生利用。%The crosslinked chitosan/attapulgite composite resin(TA-CAR) was prepared by emulsion cross-linking with tannic acid(TA) as template molecule.The structure and the morphology of the resin were characterized by FT-IR and SEM,respectively.Compared with non-template resin(185 mg/g),TA-CAR shows higher adsorption selectivity and higher adsorption capacity(232 mg/g) for TA at the same adsorption conditions.The study of adsorption kinetics and isotherms shows that the sorption processes are better fitted by the pseudo-second-order equation and the Langmuir equation,respectively.The higher adsorption capacity of TA-CAR maybe attribute to the synergistic effect of special recognition site and surface adsorption on the resin.Furthermore,the desorption study implies that the introduction of attapulgite not only improves the absorbability,but also enhances the acid resistance of the resin,which ensures the recyclable of the composite resin.

  18. Influence of the tannic and gallic acids on stability of betacyanins from red beetroot (Beta vulgaris L. crude extract. INFLUÊNCIA DOS ÁCIDOS TÂNICO E GÁLICO NA ESTABILIDADE DE BETACIANINAS DO EXTRATO BRUTO DE BETERRABA VERMELHA (Beta vulgaris L.

    Directory of Open Access Journals (Sweden)

    D. A. DRUNKLER

    2008-08-01

    Full Text Available The use of e natural colorants in the food industry is limited because to its low stability under preparation, processing and storage conditions. Techniques for natural colorant’s stabilization, such as copigmentation, have been used frequently in scientific researches. The betacyanins that belong to the groups of the betalain presents in the red beetroot and are used as colorant in food. Tannic and gallic acids were used in this study as a copigment of betacyanin crude extract from red beetroot (Beta vulgaris L.. Betacyanin stability was investigated with and without tannic and gallic acid under different storage conditions in 70% ethanol extract: concentrations of 0.925g/100mL and 0.462g/100mL, pH values 5.00±0.05 and 6.80±0.05 at temperature of 25±1ºC, in the dark and in the presence of oxygen. Results revealed that pH and tannic and gallic acid addition (p<0.05 increased significantly the betacyanins half-life time. The tannic and gallic acids provided significant increase in stability of the betacyanins pigments at both concentrations evaluated, at pH value of 5.00 ± 0.05, tannic acid being more effective.

    O uso dos corantes naturais na indústria alimentícia é limitado em função de sua baixa estabilidade frente às condições de preparação, processamento e estocagem. Técnicas de estabilização de corantes naturais, tais como a copigmentação, vem encontrando destaque em pesquisas científicas. As betacianinas (coloração vermelha violeta, pertencentes ao grupo de pigmentos naturais denominados betalaínas, são as que predominam na beterraba vermelha (Beta vulgaris L., sendo utilizadas como corante em alimentos. O objetivo do presente trabalho foi avaliar a estabilidade de betacianinas em extrato de beterraba (Beta vulgaris L. etanólico a 70% adicionadas dos ácidos orgânicos tânico e gálico, nas

  19. Efeito do ácido ascórbico em massa de pão na presença do ácido tânico = Effect of ascorbic acid in bread dough in the presence of tannic acid

    Directory of Open Access Journals (Sweden)

    Ana Leticia Gomes Saraiva

    2010-07-01

    Full Text Available Pães de farinha de trigo com adição do agente oxidante ácido ascórbico foram elaborados, tentando-se encontrar a concentração de ácido tânico que melhor retivesse o ácido ascórbico, sem afetar significativamente as características reológicas e os principaisatributos sensoriais do pão. Os pães foram elaborados com a formulação de pão-padrão. Na primeira etapa, determinou-se a concentração de ácido ascórbico que melhor proporcionasse estabilidade à massa de pão-padrão (300 ppm. Na etapa seguinte, foramutilizadas na formulação da massa-padrão três concentrações diferentes de ácido tânico: 0,10; 0,20 e 0,30%, com a finalidade de se verificar a concentração que melhor retivesse o ácido ascórbico. Os pães foram elaborados com a formulação-padrão. Após o resfriamentodos pães, foi avaliada a retenção de ácido ascórbico, presente no pão de acordo com a concentração previamente determinada. Os resultados indicaram que o pão elaborado com a massa de pão-padrão (300 ppm de ácido ascórbico apresentou concentração de ácido ascórbico de 41,50 mg 100 g-1 de pão.Wheat flour breads with the addition of oxidizing agent ascorbic acid were elaborated trying to find the concentrations of tannic acid that best retained the ascorbic acid without significantly affecting the rheologic characteristics and main sensorial attributes of bread. Inthe first stage, the concentration of ascorbic acid that best provided stability to the dough (300 ppm was determined. In the following stage, three different concentrations of tannic acid were used: 0.10, 0.20 and 0.30%, with the purpose of verifying the ascorbic acid retention in the dough. The breads were elaborated with the standard formulation. After the elaboration of the breads, the ascorbic acid retention was evaluated in the previously determined concentration. The results showed that the bread elaborated with standard dough (300 ppm of ascorbic acid, presented

  20. Estimating the acidity of transition metal hydride and dihydrogen complexes by adding ligand acidity constants.

    Science.gov (United States)

    Morris, Robert H

    2014-02-05

    A simple equation (pKa(THF) = ∑AL + Ccharge + Cnd + Cd6) can be used to obtain an estimate of the pKa of diamagnetic transition metal hydride and dihydrogen complexes in tetrahydrofuran, and, by use of conversion equations, in other solvents. It involves adding acidity constants AL for each of the ligands in the 5-, 6-, 7-, or 8-coordinate conjugate base complex of the hydride or dihydrogen complex along with a correction for the charge (Ccharge = -15, 0 or 30 for x = +1, 0 or -1 charge, respectively) and the periodic row of the transition metal (Cnd = 0 for 3d or 4d metal, 2 for 5d metal) as well as a correction for d(6) octahedral acids (Cd6 = 6 for d(6) metal ion in the acid, 0 for others) that are not dihydrogen complexes. Constants AL are provided for 13 commonly occurring ligand types; of these, nine neutral ligands are correlated with Lever's electrochemical ligand parameters EL. This method gives good estimates of the over 170 literature pKa values that range from less than zero to 50 with a standard deviation of 3 pKa units for complexes of the metals chromium to nickel, molybdenum, ruthenium to palladium, and tungsten to platinum in the periodic table. This approach allows a quick assessment of the acidity of hydride complexes found in nature (e.g., hydrogenases) and in industry (e.g., catalysis and hydrogen energy applications). The pKa values calculated for acids that have bulky or large bite angle chelating ligands deviate the most from this correlation. The method also provides an estimate of the base strength of the deprotonated form of the complex.

  1. Volatile fatty acids as an added value from biowaste.

    Science.gov (United States)

    den Boer, Emilia; Łukaszewska, Agnieszka; Kluczkiewicz, Władysław; Lewandowska, Daria; King, Kevin; Reijonen, Tero; Kuhmonen, Tero; Suhonen, Anssi; Jääskeläinen, Ari; Heitto, Anneli; Laatikainen, Reino; Hakalehto, Elias

    2016-12-01

    The aim of the present work was to provide proof of concept of employing a co-culture of K. mobilis and E. coli for producing short and medium chain volatile fatty acids (VFAs) from kitchen biowaste and potato peels. To this aim, experiments were carried out at pilot-scale installation with a bioreactor of 250L. Different feeding strategies were tested under microaerobic conditions, at pH 6.0-6.5 in order to enhance chain elongation. Acetic acid and ethanol were dominating products in the initial stages of the bioprocess, but in a relatively short time of approx. 20-22h from the process start accumulation of propionic acid took place followed by a chain elongation to butyric and valeric acids. The highest final products yield of 325mg/g TS was achieved for the substrate load of 99.1g TS/L (VS of 91.1g/L) and pH 6.5, with the productivity of 448mg/L/h. However, the highest average VFAs chain length (3.77C) was observed in the process run with the loading of 63.2g TS/L and pH 6.0. In this study, we demonstrated that the existing symbiosis of the co-culture of K. mobilis and E. coli favours formation and chain elongation of VFA, induced most likely by the enhanced ethanol formation. Our finding differs from the previous research which focus mostly on anaerobic conditions of VFAs production. The results provide good basis for further optimisation of VFAs production process.

  2. ADS genes for reducing saturated fatty acid levels in seed oils

    Science.gov (United States)

    Heilmann, Ingo H.; Shanklin, John

    2010-02-02

    The present invention relates to enzymes involved in lipid metabolism. In particular, the present invention provides coding sequences for Arabidopsis Desaturases (ADS), the encoded ADS polypeptides, and methods for using the sequences and encoded polypeptides, where such methods include decreasing and increasing saturated fatty acid content in plant seed oils.

  3. Mechanisms for lowering of interfacial tension in alkali/acidic oil systems; Effect of added surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J. Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Chemical Engineering)

    1992-08-01

    This paper reports that experimental studies are conducted in order to determine the physicochemical mechanism responsible for lowering of interfacial tension in alkali, surfactant, and surfactant-enhanced alkali/acidic oil systems. A well-defined model oil is chosen to examine the influence of various surfactants and surfactant mixtures, such as oleic acid and its ionic counterpart, sodium dodecyl sulfate, petroleum sulfonate, and isobutanol, on equilibrium interfacial tension. With added surfactant alone, the interfacial tension goes through an ultralow minimum with increasing acid concentration. This proves for the first time that the un-ionized acid species plays a major role in affecting interfacial tension, and the ionized acid species.

  4. Characterization of biodegradable film based on zein and oleic acid added with nanocarbonate

    Directory of Open Access Journals (Sweden)

    Wanessa Ximenes Ribeiro

    2015-10-01

    Full Text Available Zein oleic acid films added with 1, 2 and 3 % (w/w of nanocarbonate and 30 % glycerol as plasticizer, were produced and evaluated according to their structure and functional properties. Structural characteristics were analyzed by optical and scanning electron microscopy (SEM. Water solubility and mechanical properties were determined according to ASTM methods. The increase of nanocarbonate concentration increased water solubility and influenced the color and mechanical properties. Optical and SEM of film samples added with nanocarbonate, shown low amount of pores and great fat globules size.

  5. [Progress in engineering Escherichia coli for production of high-value added organic acids and alcohols].

    Science.gov (United States)

    Wang, Jiming; Liu, Wei; Xu, Xin; Zhang, Haibo; Xian, Mo

    2013-10-01

    Confronted with the gradual exhaustion of the earth's fossil energy resources and the grimmer environmental deterioration, the bio-based process to produce high-value added platform chemicals from renewable biomass is attracting growing interest. Escherichia coli has been chosen as a workhouse for the production of many valuable chemicals due to various advantages, such as clear genetic background, convenient to be genetically modified and good growth properties with low nutrient requirements. Rational strain development of E. coli achieved by metabolic engineering strategies has provided new processes for efficiently biotechnological production of various high-value chemical building blocks. This review focuses on recent progresses in metabolic engineering of E. coli that lead to efficient recombinant biocatalysts for production of high-value organic acids such as succinic acid, 3-hydroxypropanoic acid and glucaric acid as well as alcohols like glycerol and xylitol. Besides, this review also discusses several other platform chemicals, including 2,5-furan dicarboxylic acid, aspartic acid, glutamic acid, itaconic acid, levulinic acid, 3-hydroxy-gamma-butyrolactone and sorbitol, which have not been produced by E. coli until now.

  6. Composition and Fatty Acid Profile of Goat Meat Sausages with Added Rice Bran

    Directory of Open Access Journals (Sweden)

    Fatemeh Malekian

    2014-01-01

    Full Text Available A scientific consensus on the relationship between obesity, obesity related diseases, and diet has emerged. One of the factors is overconsumption of the red meats such as pork and beef. Goat meat has the potential to replace these traditionally consumed meats. Rice bran is a rich source of antioxidants such as vitamin E. In this study, goat meat sausages were formulated to contain 0, 1.5 or 3 percent stabilized rice bran. Proximate and fatty acid composition, α-tocopherol, cholesterol concentration, and antioxidant activities of cooked goat meat sausages containing varying percentages of rice bran were measured. Data were analyzed using a fixed effects model. The fat percentage in the goat meat sausages increased in response to increasing rice bran percentages (P<0.001. Saturated fatty acids concentration decreased linearly (P<0.01, while unsaturated fatty acids and omega-3 and omega-6 fatty acids increased linearly in response to increasing rice bran percentages (P<0.05. The concentration of α-tocopherol in sausages increased linearly in response to increasing rice bran percentages (P<0.01. Also, antioxidant activity increased linearly in sausages in response to added rice bran (P<0.01. The cholesterol concentration of sausages did not vary significantly in response to added rice bran.

  7. Effect of added surfactant on interfacial tension and spontaneous emulsification in alkali/acidic oil systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J.; Bernard, C.; Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Chemical Engineering)

    1994-05-01

    An experimental investigation of the buffered surfactant-enhanced alkaline flooding system chemistry was undertaken to determine the influence of various species present on interfacial tension as a function of pH and ionic strength. Phase behavior tests that monitor the extent of emulsification are sufficient to determine the region of low interfacial tension. Optimization of interfacial tension by adjustment of the ionic strength alone may not necessarily provide the lowest interfacial tension under the best conditions. The pH should be simultaneously optimized along with ionic strength to allow better control over attainment of low interfacial tension. The dominant mechanism by which added surfactant aids in the reduction of interfacial tension is the formation of mixed micelles with the ionized acid. Although added surfactant partitioning from the influence of the un-ionized acid and ionic strength will affect interfacial behavior, the formation of mixed micelles plays a dominant role. Middle-phase formation is possible with a low acid oil using a petroleum sulfonate at a proper pH and ionic strength.

  8. Fast enantioselective separation of clevidipine and a dihydropyridine substituted acid by SFC on Chiralpak AD.

    Science.gov (United States)

    Gyllenhaal, O

    2001-01-01

    Conditions for the fast separation of the enantiomers of a dihydropyridine substituted acid on a 50 x 4.6 mm ID short Chiralpak AD column with 2-propanol modified carbon dioxide as the mobile phase are presented. A high throughout of samples can be accomplished through the continuous sample loading of the loop of the injector. If a continuous data collection was used 10 separations could be performed in about 5 min with a precision of 0.6% RSD for the area ratio (n = 10). The parent drug clevidipine can also be analyzed and its enantiomeric composition determined after alkaline hydrolysis into its acid, either through hydrolysis followed by extraction to dichloromethane or by direct analysis of the hydrolysis media. About 1 min is required for each run. Using 0.1 M of methanolic sodium hydroxide 2 min are sufficient for the hydrolysis, and, including weighing, only 5 min are required to analyze clevidipine.

  9. Effect of added caffeic acid and tyrosol on the fatty acid and volatile profiles of camellia oil following heating.

    Science.gov (United States)

    Haiyan, Zhong; Bedgood, Danny R; Bishop, Andrea G; Prenzler, Paul D; Robards, Kevin

    2006-12-13

    Camellia oil is widely used in some parts of the world partly because of its high oxidative stability. The effect of heating a refined camellia oil for 1 h at 120 degrees C or 2 h at 170 degrees C with exogenous antioxidant, namely, caffeic acid and tyrosol, was studied. Parameters used to assess the effect of heating were peroxide and K values, volatile formation, and fatty acid profile. Of these, volatile formation was the most sensitive index of change as seen in the number of volatiles and the total area count of volatiles in gas chromatograms. Hexanal was generally the dominant volatile in treated and untreated samples with a concentration of 2.13 and 5.34 mg kg(-1) in untreated oils heated at 120 and 170 degrees C, respectively. The hexanal content was significantly reduced in heated oils to which tyrosol and/or caffeic acid had been added. Using volatile formation as an index of oxidation, tyrosol was the more effective antioxidant of these compounds. This is contradictory to generally accepted antioxidant structure-activity relationships. Changes in fatty acid profiles after heating for up to 24 h at 180 degrees C were not significant.

  10. Predicting Reaction Mechanisms and Potentials in Acid and Base from Self-Consistent Quantum Theory: H(ads) and OH(ads) Deposition on the Pt(111) Electrode.

    Science.gov (United States)

    Zhao, Meng; Anderson, Alfred B

    2016-02-18

    It has been shown recently that when reactants and products are well modeled within a comprehensive self-consistent theory for the electrochemical interface, accurate predictions are possible for reversible potentials, Urev, in acid electrolyte for reactions such as reduction of H(+)(aq) to form under potential deposited H(ads) and oxidation of an OH bond of H2O(ads) to deposit OH(ads). Predictions are based on calculated Gibbs energies for the reactant and product being equal at the reversible potential, which is the potential at the crossing point for reaction and product Gibbs energies, plotted as functions of electrode potential. In this Letter, it is demonstrated that the same capability holds for these reactions in basic electrolyte. This demonstration opens up the opportunity for predictions of reversible potentials and mechanisms for other electrocatalytic reactions in base.

  11. Salmonella fecal excretion control in broiler chickens by organic acids and essential oils blend feed added

    Directory of Open Access Journals (Sweden)

    A Borsoi

    2011-03-01

    Full Text Available Salmonellosis is an important disease with economic impact as it may affect animal performance and may result in foodborne disease in humans through the eggs and carcass contamination. Regarding the Salmonella control, it is possible to decrease its fecal excretion and the contamination of chicken carcasses by adding organic acids to the feed or drinking water at appropriate times. The aim of this study was to test a blend of organic acids and essential oils in broilers challenged with Salmonella Enteritidis (SE, and to verify the fecal excretion of Salmonella. Sixty broilers were placed in four groups. One group was the negative control. Another group was orally inoculated at 1 day-old with 10(5 CFU/mL of SE as a positive SE control. Two groups (T3 and T4 were orally inoculated at 1 day-old with 10(5 CFU/mL of SE and their feed was separately treated with 0.5 and 1% of organic acids and essential oils, respectively. To assess the fecal excretion of SE, cloacal swabs were collected from all birds at 2, 6, 13 and 20 days after inoculation. The T3 and T4 groups showed a reduction in fecal excretion of SE at 6 and 20 days after inoculation.

  12. Investigation on the levitation force behaviour of malic acid added bulk MgB{sub 2} superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Savaskan, B., E-mail: burcusavaskan@hotmail.com [Energy Systems Engineering, Faculty of Technology, Karadeniz Technical University, 61830 Of, Trabzon (Turkey); Taylan Koparan, E. [Department of Primary Education, Eregli Faculty of Education, Bulent Ecevit University, TR-67300 Zonguldak (Turkey); Celik, S. [Department of Physics, Faculty of Arts and Sciences, Recep Tayyip Erdogan University, 53100 Rize (Turkey); Ozturk, K.; Yanmaz, E. [Department of Physics, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon (Turkey)

    2014-07-15

    Highlights: • The effects of malic acid addition on the levitation force properties of bulk MgB{sub 2} has been first time investigated and reported. • The malic acid adding has a positive impact on the levitation properties. • 4 wt% and 6 wt% malic acid added samples exhibited a higher vertical and lateral force than pure sample. - Abstract: The effects of malic acid addition (from 0 to 15 wt% of the total MgB{sub 2}) on the levitation force properties of bulk MgB{sub 2} have been investigated. All samples were prepared from magnesium powder, amorphous boron powder, malic acid (C{sub 4}H{sub 6}O{sub 5}) and toluene (C{sub 7}H{sub 8}) by using two-step solid state reaction method. Vertical and lateral levitation force measurements that are under both zero-field-cooled (ZFC) and field-cooled (FC) regimes were carried out at different temperatures of 24, 28 and 32 K for samples with various adding level. It was found that the reasonable malic acid adding has a positive impact on the levitation properties. At 24 K and 28 K, the 4 wt% and 6 wt% malic acid added samples exhibits a higher levitation force than pure sample. In the case of the optimally additive 4 wt% sample, the maximum levitation force corresponds to 18.60 N, whereas the pure sample shows 16.95 N at 24 K for ZFC regime. In this study the enhancing effect of malic acid adding on the levitation force properties of MgB{sub 2} has been first time investigated and reported.

  13. Reversal of elution order for profen acid enantiomers in packed-column SFC on Chiralpak AD.

    Science.gov (United States)

    Gyllenhaal, Olle; Stefansson, Morgan

    2005-05-15

    Enantiomeric separations of four 2-substituted propionic acid drugs have been studied using packed-column supercritical fluid chromatography (SFC) with amylose tris(3,5-dimethylphenylcarbamate) coated on silica as support (Chiralpak AD). Under standard conditions (i.e., flow rate, 1.5 ml/min; column temperature, 30 degrees C; back-pressure, 150 bar), the order of elution could be reversed when the polar alcohol modifier methanol in carbon dioxide was replaced by 2-propanol for ibuprofen, ketoprofen, and naproxen. For flurbiprofen, with the highest selectivity factor, no reversal was observed, although selectivity was reduced significantly with higher alcohols. Naproxen and flurbiprofen were also investigated with 2-butanol and 2-pentanol. The former showed reversal of elution order but not the latter. For higher alcohol modifiers, including 2-propanol, the peak symmetry was poor but could be improved by addition of citric acid in the alcohol modifier. These results stress the importance to investigate enantiomer elution order during the development of enantioselective methods and when chromatographic conditions are optimized. Preliminary experiments with column temperatures over the range of -15 to 45 degrees C revealed that, in a few cases, reversal took place with a change in temperature only.

  14. The Organoleptic and Physic Characteristics and Lactic Acid Contents of Yoghurt with Commercial Starter Added Bifidobacteria bifidum

    Directory of Open Access Journals (Sweden)

    Tatik Khusniati

    2012-10-01

    Full Text Available Bifidobacteria bifidum is probiotic bacteria which inhibit negative bacteria in human ulcer. Adding B. bifidum in commercial yoghurt starter, may increase yoghurt quality. To know yoghurt quality, organoleptic and physic characteristics and lactic acidcontents of yoghurt with commercial starter added B. bifidum was observed. B. bifidum concentrations added were 1:4, 2:4, 3:4 (v/v. Organoleptic characteristics were conducted by 18 panelists, physics were visually detected and lactic acid contents were by titration method. The results show that accepted yoghurt characteristics were yoghurt with commercial starter added B. bifidum 1:4 (v/v, and fat yoghurt were more acceptable than that skim. The higher B. bifidum concentrations used, the stronger flavours (after expiry date and colours (at and after expiry date of yoghurt, while yoghurt homogenity decreased (at and after expiry date. Fat yoghurt flavours were stronger than that of skim. The higher B. bifidum concentrations and storage times, the higher yoghurt lactic acid contents. Lactic acid contents of fat yoghurt with various starters, were higher than that skim at storage 0-15 days. The fat yoghurt lactic acid contents were 0.99%-1.44%, while that skim were 0.95-1.20%. Based on organoleptic and physic characteristics and lactic acid contents, fat yoghurt were more acceptable that that skim.

  15. Reactions of enolisable ketones with dichloroisocyanuric acid in absence and presence of added chloride ions – a kinetic study

    Directory of Open Access Journals (Sweden)

    Y. L. Kumar

    2015-01-01

    Full Text Available Kinetics of reactions of enolisable ketones (S = acetone/2-butanone with dichloroisocyanuric acid (DCICA were studied in aqueous acetic acid and perchloric acid media in absence and presence of added chloride ions. The reactions were found to be pseudo zero order and pseudo first order on [DCICA] in absence and presence of chloride ions respectively. Both in presence and absence of chloride ions, first order and fractional order in substrate and perchloric acid were observed respectively. An increase in the rate of reaction was observed with an increase in chloride ion concentration as well as acetic acid composition. The results were interpreted in terms of probable mechanisms involving (i rate-determining enol formation from the conjugate acid of the ketone (SH+ in the absence of added chloride ions and (ii rate-determining interaction of SH+ with the most effective molecular chlorine species produced by the hydrolysis of DCICA (rather than a rate-determining interaction of enol with chlorine in the presence of added chloride ions, prior to the rapid steps of product formation. DOI: http://dx.doi.org/10.4314/bcse.v29i1.12

  16. Lipid and fatty acid metabolism in Ralstonia eutropha: relevance for the biotechnological production of value-added products.

    Science.gov (United States)

    Riedel, Sebastian L; Lu, Jingnan; Stahl, Ulf; Brigham, Christopher J

    2014-02-01

    Lipid and fatty acid metabolism has been well studied in model microbial organisms like Escherichia coli and Bacillus subtilis. The major precursor of fatty acid biosynthesis is also the major product of fatty acid degradation (β-oxidation), acetyl-CoA, which is a key metabolite for all organisms. Controlling carbon flux to fatty acid biosynthesis and from β-oxidation allows for the biosynthesis of natural products of biotechnological importance. Ralstonia eutropha can utilize acetyl-CoA from fatty acid metabolism to produce intracellular polyhydroxyalkanoate (PHA). R. eutropha can also be engineered to utilize fatty acid metabolism intermediates to produce different PHA precursors. Metabolism of lipids and fatty acids can be rerouted to convert carbon into other value-added compounds like biofuels. This review discusses the lipid and fatty acid metabolic pathways in R. eutropha and how they can be used to construct reagents for the biosynthesis of products of industrial importance. Specifically, how the use of lipids or fatty acids as the sole carbon source in R. eutropha cultures adds value to these biotechnological products will be discussed here.

  17. Treatment of Alzheimer's disease with anti-homocysteic acid antibody in 3xTg-AD male mice.

    Directory of Open Access Journals (Sweden)

    Tohru Hasegawa

    Full Text Available Alzheimer's disease (AD is an age-associated progressive neurodegenerative disorder with dementia, the exact pathogenic mechanisms of which remain unknown. We previously reported that homocysteic acid (HA may be one of the pathological biomarkers in the brain with AD and that the increased levels of HA may induce the accumulation of intraneuronal amyloid-beta (Abeta peptides. In this study, we further investigated the pathological role of HA in a mouse model of AD. Four-month-old prepathological 3xTg-AD mice exhibited higher levels of HA in the hippocampus than did age-matched nontransgenic mice, suggesting that HA accumulation may precede both Abeta and tau pathologies. We then fed 3-month-old 3xTg-AD mice with vitamin B6-deficient food for 3 weeks to increase the HA levels in the brain. Concomitantly, mice received either saline or anti-HA antibody intraventricularly via a guide cannula every 3 days during the course of the B6-deficient diet. We found that mice that received anti-HA antibody significantly resisted cognitive impairment induced by vitamin B6 deficiency and that AD-related pathological changes in their brains was attenuated compared with the saline-injected control group. A similar neuroprotective effect was observed in 12-month-old 3xTg-AD mice that received anti-HA antibody injections while receiving the regular diet. We conclude that increased brain HA triggers memory impairment and that this condition deteriorates with amyloid and leads to subsequent neurodegeneration in mouse models of AD.

  18. Berberine target key enzymes and amino acid inibitiors in AD treatment-----creation from berberine-based structure screening

    Directory of Open Access Journals (Sweden)

    Yau Lam

    2014-07-01

    Full Text Available The main components of berberine from coptis have a variety of pharmacological activity include the treatment of neurodegenerative diseases, Alzheimer’s disease (AD. The principle of berberine is inhibiting the lower activity of enzyme and amino acid to prevent (AD. Enzyme like acetylcholinesterase enzyme (AchE, butyrylcholinesterase enzyme (BchE and monoamine oxidase (MAO; Amino acid like beta-amyloid (Aβ. Unfortunately, the single chemical structures of berberine is no significance to regulation effect. As a part of our consideration, the review paper studies on chemically modified and synthesis from berberine-derivatives. Results show that the structures of (23, (10, (86, (52, and (61 have a potential effect for AchE, BuChE and Aβ-amyloid inhibitors for the first time. Especially in (23 and (52 also has better than two western medicine were compared.

  19. Value-added lipid production from brown seaweed biomass by two-stage fermentation using acetic acid bacterium and thraustochytrid.

    Science.gov (United States)

    Arafiles, Kim Hazel V; Iwasaka, Hiroaki; Eramoto, Yuri; Okamura, Yoshiko; Tajima, Takahisa; Matsumura, Yukihiko; Nakashimada, Yutaka; Aki, Tsunehiro

    2014-11-01

    Thraustochytrid production of polyunsaturated fatty acids and xanthophylls have been generally sourced from crop-derived substrates, making the exploration of alternative feedstocks attractive since they promise increased sustainability and lower production costs. In this study, a distinct two-stage fermentation system was conceptualized for the first time, using the brown seaweed sugar mannitol as substrate for the intermediary biocatalyst Gluconobacter oxydans, an acetic acid bacterium, along with the marine thraustochytrid Aurantiochytrium sp. to produce the value-added lipids and xanthophylls. Jar fermenter culture resulted in seaweed mannitol conversion to fructose with an efficiency of 83 % by G. oxydans and, after bacteriostasis with sea salts, production of astaxanthin and docosahexaenoic acid by Aurantiochytrium sp. KH105. Astaxanthin productivity was high at 3.60 mg/L/day. This new system, therefore, widens possibilities of obtaining more varieties of industrially valuable products including foods, cosmetics, pharmaceuticals, and biofuel precursor lipids from seaweed fermentation upon the use of suitable thraustochytrid strains.

  20. Microwave assisted conversion of microcrystalline cellulose into value added chemicals using dilute acid catalyst.

    Science.gov (United States)

    Ching, Teck Wei; Haritos, Victoria; Tanksale, Akshat

    2017-02-10

    One of the grand challenges of this century is to transition fuels and chemicals production derived from fossil feedstocks to renewable feedstocks such as cellulosic biomass. Here we describe fast microwave conversion of microcrystalline cellulose (MCC) in water, with dilute acid catalyst to produce valuable platform chemicals. Single 10min microwave assisted treatment was able to convert >60% of MCC, with >50mol% yield of desirable products such as glucose, HMF, furfural and levulinic acid. Recycling of residual MCC with make-up fresh MCC resulted in an overall conversion of >93% after 5 cycles while maintaining >60% conversion in each cycle. Addition of isopropanol (70%v/v) as a co-solvent increased the yields of HMF and levulinic acid. This work shows for the first time proof of concept for complete conversion of recalcitrant microcrystalline cellulose in mild conditions of low temperature, dilute acid and short residence time using energy efficient microwave technology.

  1. Survival of the functional yeast Kluyveromyces marxianus B0399 in fermented milk with added sorbic acid.

    Science.gov (United States)

    Tabanelli, G; Verardo, V; Pasini, F; Cavina, P; Lanciotti, R; Caboni, M F; Gardini, F; Montanari, C

    2016-01-01

    In this study, the survival of the functional yeast Kluyveromyces marxianus B0399 in an industrially produced fermented milk was evaluated. In particular, the yeast viability was assessed throughout the entire shelf-life of the product (30 d) to ensure the presence of the effective yeast dose (20 million viable cells for each serving of 125 g) while avoiding, by sorbic acid addition, yeast growth, which could affect product quality and stability. To find the best combination of yeast and sorbic acid concentration, 13 different combinations were tested, and then 2 of them were chosen for industrial production. In production at lower concentrations (30 million viable cells, 150 mg/kg of sorbic acid) the effective dose was maintained only at 4 and 6°C, whereas at higher dosages (70 million viable cells, 250 mg/kg of sorbic acid) the effect of temperature was less evident. In all the trials, the concentration of sorbic acid was not affected by microbial metabolism and remained stable throughout the entire shelf-life.

  2. Wheat straw hemicelluloses added with cellulose nanocrystals and citric acid. Effect on film physical properties.

    Science.gov (United States)

    Pereira, Paulo H F; Waldron, Keith W; Wilson, David R; Cunha, Arcelina P; Brito, Edy S de; Rodrigues, Tigressa H S; Rosa, Morsyleide F; Azeredo, Henriette M C

    2017-05-15

    Wheat straw has been used as a source of hemicelluloses (WSH) and cellulose nanocrystals (CNC) for the elaboration of biodegradable films. Different films have been formed by using WSH as a matrix and different contents of CNC and citric acid. The predominant hemicelluloses were arabinoxylans. CNC reinforced the films, improving tensile strength and modulus, water resistance and water vapor barrier. Citric acid, on the other hand, presented concomitant plasticizing and crosslinking effects (the latter also evidenced by FTIR), probably due to a crosslinking extension by glycerol. The use of 5.9wt% CNC and 30wt% citric acid was defined as optimal conditions, resulting in minimum water sensitivity and permeability, while maintaining a good combination of tensile properties. Under those conditions, the films presented enhanced modulus, elongation, water resistance, and barrier to water vapor when compared to the control WSH film, and might be used for wrapping or coating a variety of foods.

  3. Enhancement and modeling of microparticle-added Rhizopus oryzae lactic acid production.

    Science.gov (United States)

    Coban, Hasan Bugra; Demirci, Ali

    2016-02-01

    Lactic acid has a wide industrial application area and can be produced by fungal strains. However, excessive bulk growth form of fungi during the fermentations is a major problem, which limits the fermentation performance. Microparticles are excellent tools to prevent bulk fungal growth and provide homogenized fermentation broth to increase uniformity and the prediction performance of the models. Therefore, in this study, addition of aluminum oxide and talcum microparticles into fermentations was evaluated to enhance the production of lactic acid by Rhizopus oryzae. The results showed that the bulk fungal growth was prevented and the lactic acid concentration increased from 6.02 to 13.88 and 24.01 g/L, when 15 g/L of aluminum oxide or 10 g/L of talcum was used, respectively, in the shake-flask fermentations. Additionally, substrate concentration, pH, and agitation were optimized in the bioreactors using response surface methodology, and optimum values were determined as 126 g/L of glucose, 6.22 pH, and 387 rpm, respectively. Under these conditions, lactic acid production further increased to 75.1 ± 1.5 g/L with 10 g/L of talcum addition. Also, lactic acid production and glucose consumption in the batch fermentation were successfully modeled with modified Gompertz model and modified logistic model. RMSE and MAE values for lactic acid production were calculated as 2.279 and 1.498 for the modified Gompertz model; 3.6 and 4.056 for the modified logistic model. Additionally, modified logistic model predicted glucose consumption with -2.088 MAE and 2.868 RMSE, whereas these values were calculated as 2.035 and 3.946 for the modified Gompertz model.

  4. Mass Attenuation Coefficients of Binderless and Polylactic Acid Added Oil Palm Trunk Particleboard in the Diagnostic Energy Range

    Directory of Open Access Journals (Sweden)

    Mohana Baskaran

    2015-01-01

    Full Text Available Two types of oil palm trunk particleboards namely binderless and polylactic acid (PLA added board were manufactured with a target density of 1.0 g/cm3. The mass attenuation coefficients of the binderless and PLA added particleboards were determined by using X-ray fluorescence (XRF photons emanating from high purity metal plates. The energies of the XRF emitted from those metal plates were in the range of 16.59 keV– 25.26 keV. The experimental values of the mass attenuation coefficients of the binderless particleboards and the XCOM calculated values for water are comparable. These results suggest that binderless particleboards have the potential to be a phantom material at diagnostic photon energies.

  5. Technological, physicochemical and sensory characteristics of a Brazilian semi-hard goat cheese (coalho with added probiotic lactic acid bacteria

    Directory of Open Access Journals (Sweden)

    Maria Elieidy Gomes de Oliveira

    2012-12-01

    Full Text Available Over the past few years, the use of probiotics, which are capable of exerting beneficial effects on the composition of intestinal microbiota, has increased. Cheeses have been suggested as a better carrier of probiotic bacteria than other fermented milk products. The effect of added cultures of probiotic lactic acid bacteria on the quality of a Brazilian goat semi-hard cheese (coalho was assessed during 21 days of storage at 10 ºC as follows: C1, Lactococcus lactis subsp. lactis and L. lactis subsp. Cremoris (standard cheese; C2, Lactobacillus acidophilus (LA-5; C3, Lactobacillus paracasei (Lactobacillus casei-01; C4, BBifidobacterium lactis (BB12; and C5, L. acidophilus, L. paracasei and B. lactis. Differences in some physico-chemical, experimental texture and proteolysis parameters were found among the assessed cheeses. All of them presented high luminosity (L* with predominance of the yellow component (b*. Numbers of lactic acid bacteria in the cheeses were greater than 10(7 cfu g-1 during storage. Cheeses with the added probiotic strains alone and in co-culture were better accepted than cheeses without the probiotic strains. It is suggested that goat "coalho" cheese could be a potential carrier of probiotic lactic acid bacteria.

  6. Hydrophobically Modified Polyelectrolytes: V. Interaction of Fluorocarbon Modified Poly (acrylic acid) with Various Added Surfactants

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Hui(周晖); SONG,Guo-Qaiang(宋国强); GUO,Jin-Feng(郭金峰); ZHANG,Yun-xiang (章云祥); DIEING,Reinhold; MA,Lian(马莲); HAEUSSLING,Lukas

    2001-01-01

    The interactions between fiuorocarbon-medified pol(sodium acrylate) and various kinds of added surfactant have been studied by means of viscometric measurement. Association behavior was found in both hydrogenated and fluorinated anionic, nonionic and cationic surfactants. Among them, the interactions between fluorocarbon-modified poly ( sodium acrylate) and cationic surfactants are the strongest, owing to the cooperation of both electrostatic attractions and hydrophobic associations. The anionic surfactants have the weakest effects on the solution properties because of the existence of unfavorable electrostatic repulsion. The hydrophobic interactions between copolymers and fluorinated surfactants are much stronger than those between copolymers and hydrogenated surfactants.

  7. Partial characterization of chayotextle starch-based films added with ascorbic acid encapsulated in resistant starch.

    Science.gov (United States)

    Martínez-Ortiz, Miguel A; Vargas-Torres, Apolonio; Román-Gutiérrez, Alma D; Chavarría-Hernández, Norberto; Zamudio-Flores, Paul B; Meza-Nieto, Martín; Palma-Rodríguez, Heidi M

    2017-05-01

    Chayotextle starch was modified by subjecting it to a dual treatment with acid and heating-cooling cycles. This caused a decrease in the content of amylose, which showed values of 30.22%, 4.80%, 3.27% and 3.57% for native chayotextle starch (NCS), starch modified by acid hydrolysis (CMS), and CMS with one (CMS1AC) and three autoclave cycles (CMS3AC), respectively. The percentage of crystallinity showed an increase of 36.9%-62% for NCS and CMS3AC. The highest content of resistant starch (RS) was observed in CMS3AC (37.05%). The microcapsules were made with CMS3AC due to its higher RS content; the total content of ascorbic acid of the microcapsules was 82.3%. The addition of different concentrations of CMS3AC microcapsules (0%, 2.5%, 6.255% and 12.5%) to chayotextle starch-based films (CSF) increased their tensile strength and elastic modulus. The content of ascorbic acid and RS in CSF was ranged from 0% to 59.4% and from 4.84% to 37.05% in the control film and in the film mixed with CMS3AC microcapsules, respectively. Water vapor permeability (WVP) values decreased with increasing concentrations of microcapsules in the films. Microscopy observations showed that higher concentrations of microcapsules caused agglomerations due their poor distribution in the matrix of the films. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Crystal structure of nicotinic acid mononucleotide adenylyltransferase from Staphyloccocus aureus: structural basis for NaAD interaction in functional dimer.

    Science.gov (United States)

    Han, Seungil; Forman, Michael D; Loulakis, Pat; Rosner, Michelle H; Xie, Zhi; Wang, Hong; Danley, Dennis E; Yuan, Wei; Schafer, John; Xu, Zuoyu

    2006-07-21

    Bacterial nicotinic acid mononucleotide adenylyltransferase (NaMNAT; EC 2.7.7.18) encoded by the nadD gene, is essential for cell survival and is thus an attractive target for developing new antibacterial agents. The NaMNAT catalyzes the transfer of an adenylyl group of ATP to nicotinic acid mononucleotide (NaMN) to form nicotinic acid dinucleotide (NaAD). Two independently derived, high-resolution structures of Staphylococcus aureus NaMNAT-NaAD complexes establish the conserved features of the core dinucleotide-binding fold with other adenylyltransferases from bacteria to human despite a limited sequence conservation. The crystal structures reveal that the nicotinate carboxylates of NaAD are recognized by interaction with the main-chain amides of Thr85 and Tyr117, a positive helix dipole and two bridged-water molecules. Unlike other bacterial adenylyltransferases, where a partially conserved histidine residue interacts with the nicotinate ring, the Leu44 side-chain interacts with the nicotinate ring by van der Waals contact. Importantly, the S. aureus NaMNAT represents a distinct adenylyltransferase subfamily identifiable in part by common features of dimerization and substrate recognition in the loop connecting beta5 to beta6 (residues 132-146) and the additional beta6 strand. The unique beta6 strand helps orient the residues in the loop connecting beta5 to beta6 for substrate/product recognition and allows the beta7 strand structural flexibility to make key dimer interface interactions. Taken together, these structural results provide a molecular basis for understanding the coupled activity and recognition specificity for S. aureus NaMNAT and for rational design of selective inhibitors.

  9. Exploitation of sweet cherry (Prunus avium L.) puree added of stem infusion through fermentation by selected autochthonous lactic acid bacteria.

    Science.gov (United States)

    Di Cagno, Raffaella; Surico, Rosalinda Fortunata; Minervini, Giovanna; Rizzello, Carlo Giuseppe; Lovino, Raffaella; Servili, Maurizio; Taticchi, Agnese; Urbani, Sefania; Gobbetti, Marco

    2011-08-01

    Strains of Lactobacillus plantarum, Pediococcus acidilactici, Pediococcus pentosaceus and Leuconostoc mesenteroides subsp. mesenteroides were identified from 8 cultivars of sweet cherry by partial 16S rRNA gene sequence and subjected to typing by Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) analysis. Representative isolates from each species and each cultivar were screened based on the kinetics of growth on cherry puree added of (10%, v/v) stem infusion (CP-SI). A protocol for processing and storage of CP-SI, which included fermentation by selected autochthonous P. pentosaceus SWE5 and L. plantarum FP3 (started CP-SI) or spontaneous fermentation (unstarted CP-SI), was set up. Starters grew and remained viable at elevated cell numbers (ca. 9.0 log cfu g(-1)) during 60 days of storage at 4 °C. The number of presumptive lactic acid bacteria of the unstarted CP-SI did not exceed the value of ca. 3.0 log cfu g(-1). Consumption of carbohydrates (e.g., glucose and fructose) by starter lactic acid bacteria was limited as well as it was the lactic acid fermentation. Consumption of organic acids (e.g., malic acid) and free amino acids was evident, especially, throughout storage. Compared to CP-SI before processing, the concentrations of total phenolic compounds and anthocyanins did not vary in the started CP-SI. The concentration of anthocyanins slightly decreased in the unstarted CP-SI. The antioxidant activity, expressed as the scavenging activity toward DPPH radical, was found at highest level in the started CP-SI which approached that found in CP-SI before processing. During storage, viscosity and, especially, color indexes of started CP-SI were higher than those found in the unstarted CP-SI. Fermentation by autochthonous lactic acid bacteria seemed to also positively interfere with the sensory attributes of CP-SI.

  10. Sorbic and benzoic acid in non-preservative-added food products in Turkey.

    Science.gov (United States)

    Cakir, Ruziye; Cagri-Mehmetoglu, Arzu

    2013-01-01

    Sorbic acid (SA) and benzoic acid (BA) were determined in yoghurt, tomato and pepper paste, fruit juices, chocolates, soups and chips in Turkey by using high-pressure liquid chromatography (HPLC). Levels were compared with Turkish Food Codex limits. SA was detected only in 2 of 21 yoghurt samples, contrary to BA, which was found in all yoghurt samples but one, ranging from 10.5 to 159.9 mg/kg. Both SA and BA were detected also in 3 and 6 of 23 paste samples in a range of 18.1-526.4 and 21.7-1933.5 mg/kg, respectively. Only 1 of 23 fruit juices contained BA. SA was not detected in any chips, fruit juice, soup, or chocolate sample. Although 16.51% of the samples was not compliant with the Turkish Food Codex limits, estimated daily intake of BA or SA was below the acceptable daily intake.

  11. Composition and Fatty Acid Profile of Goat Meat Sausages with Added Rice Bran

    OpenAIRE

    Fatemeh Malekian; Margarita Khachaturyan; Sebhatu Gebrelul; Henson, James F.

    2014-01-01

    A scientific consensus on the relationship between obesity, obesity related diseases, and diet has emerged. One of the factors is overconsumption of the red meats such as pork and beef. Goat meat has the potential to replace these traditionally consumed meats. Rice bran is a rich source of antioxidants such as vitamin E. In this study, goat meat sausages were formulated to contain 0, 1.5 or 3 percent stabilized rice bran. Proximate and fatty acid composition, α-tocopherol, cholesterol concent...

  12. RETRACTED: Crystal growth and spectroscopic characterization of Aloevera amino acid added lithium sulfate monohydrate: A non-linear optical crystal

    Science.gov (United States)

    Manimekalai, R.; Antony Joseph, A.; Ramachandra Raja, C.

    2014-03-01

    This article has been retracted: please see Elsevier Policy on Article Withdrawal. This article has been retracted at the request of authors. According to the author we have reported Aloevera Amino Acid added Lithium sulphate monohydrate [AALSMH] crystal is a new nonlinear optical crystal. From the recorded high performance liquid chromatography spectrum, by matching the retention times with the known compounds, the amino acids present in our extract are identified as homocystine, isoleucine, serine, leucine and tyrosine. From the thin layer chromatography and colorimetric estimation techniques, presence of isoleucine was identified and it was also confirmed by NMR spectrum. From the above studies, we came to conclude that AALSMH is new nonlinear optical crystal. After further investigation, lattice parameter values of AALSMH are coinciding with lithium sulphate. Therefore we have decided to withdraw our paper. Sorry for the inconvenience and time spent.

  13. Promoted degradation of perfluorooctanic acid by persulfate when adding activated carbon.

    Science.gov (United States)

    Lee, Yu-Chi; Lo, Shang-Lien; Kuo, Jeff; Huang, Chin-Pao

    2013-10-15

    Treatment of persistent perfluorooctanoic acid (PFOA) in water using persulfate (PS) oxidation typically requires an elevated temperature or UV irradiation, which is energy-consuming. Under relatively low temperatures of 25-45°C, activated carbon (AC) activated PS oxidation of PFOA was evaluated for its potential of practical applications. With presence of AC in PS oxidation, PFOA removal efficiency at 25°C reached 682% with a high defluorination efficiency of 549% after 12h and few intermediates of short-chain perfluorinated carboxylic acids (PFCAs) were found. The removal and defluorination rates with the combined AC/PS system were approximately 12 and 19 times higher than those of the PS-only system, respectively. Activated carbon not only removes PFOA through adsorption, but also activates PS to form sulfate radicals that accelerate the decomposition and mineralization of PFOA. The activation energy for PS oxidation of PFOA was reduced from 668 to 261kJ/mol by the catalytic effect of AC, which implies a lower reaction temperature and a shorter reaction time would suffice. A 2-cycle schematic reaction mechanism was used to describe PS oxidation of PFOA with the generation of various intermediates and end-products.

  14. Effects of adding supplemental tallow to diets containing distillers dried grains with solubles on fatty acid digestibility in growing pigs.

    Science.gov (United States)

    Davis, J M; Urriola, P E; Baidoo, S K; Johnston, L J; Shurson, G C

    2015-01-01

    An experiment was conducted to measure the apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of fatty acids in diets containing 0 or 30% corn distillers dried grains with solubles (DDGS) and 0, 5, or 10% tallow. Barrows (n = 24; initial BW = 25 kg) were surgically fitted with a T-cannula at the distal ileum. Pigs (n = 4/diet) were randomly assigned to diets: corn-soybean meal control (CON), CON plus 5% tallow (5T0D), CON plus 10% tallow (10T0D), CON plus 30% DDGS (0T30D), CON plus 5% tallow and 30% DDGS (5T30D), and CON plus 10% tallow and 30% DDGS (10T30D). Eight replicates per treatment were achieved by randomizing diets among pigs for a second collection period. Each pig was fed their respective diet for a 5-d adaptation period followed by 3-d fecal collection and 2-d ileal digesta collection periods. The AID and ATTD of fatty acids was calculated using the index method and acid-insoluble ash as an indigestible marker. When tallow was added to diets with 0% DDGS, there was no effect on AID of palmitic acid (C16:0) or SFA, while AID of stearic acid (C18:0) was increased (66.87% for CON, 72.06% for 5T0D, and 76.81% for 10T0D; P tallow increased C16:0 (77.62% for 0T30D, 69.66% for 5T30D, and 68.43% for 10T30D), C18:0 (85.87% for 0T30D, 64.08% for 5T30D, and 61.25% for 10T30D), and SFA (79.88% for 0T30D, 68.23% for 5T30D, and 66.29% for 10T30D). The AID of MUFA was not affected when tallow was added to diets with 30% DDGS but actually increased in 5T0D and 10T0D. The amount of apparent ileal digested fatty acids increased with the addition of DDGS and tallow regardless of their digestibility. Amounts of ileal digested MUFA and PUFA increased when both DDGS (P tallow (P tallow was observed. Interactions between DDGS and tallow were observed for ATTD of all fatty acids (P tallow addition independent from the inclusion level of DDGS and it was a function the dietary concentration of the fatty acid. Adding tallow to corn-soybean based

  15. Compound amino acids added in media improved Solanum nigrum L. phytoremediating CD-PAHS contaminated soil.

    Science.gov (United States)

    Wei, Shuhe; Bai, Jiayi; Yang, Chuanjie; Zhang, Qianru; Knorrm, Klaus-Holger; Zhan, Jie; Gao, Qianhui

    2016-01-01

    Cd hyperaccumulator Solanum nigrum L. was a promising plant used to simultaneously remediate Cd-PAHs combined pollution soil through its extra accumulation capacity and rhizosphere degradation. This article compared the strengthening remediation role of cysteine (Cys), glycine (Gly) and glutamic acid (Glu) with EDTA and TW80. The results showed that the addition of 0.03 mmol L(-1) Cys, Gly, and Glu didn't significantly impact (p Cd concentration. Therefore, Cd capacity (µg pot(-1)) in shoots of S. nigrum was significantly increased (p Cd might lie in the addition of Cys, Gly, and Glu which reduced pH and increased extractable Cd concentration in rhizosphere and phytochelatines (PCs) concentration in leaves. As for the degradation of PAHs in rhizosphere, increased microorganism number might be play important role.

  16. Promoted degradation of perfluorooctanic acid by persulfate when adding activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yu-Chi [Research Center for Environmental Pollution Prevention and Control Technology, Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC (China); Lo, Shang-Lien, E-mail: sllo@ntuedu.tw [Research Center for Environmental Pollution Prevention and Control Technology, Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan, ROC (China); Kuo, Jeff [Department of Civil and Environmental Engineering, California State University, 800 North, State College Blvd., Fullerton (United States); Huang, Chin-Pao [Department of Civil and Environmental Engineering, University of Delaware, Newark, DE 19716 (United States)

    2013-10-15

    Highlights: • PFOA removal and defluorination with AC/PS are 12 and 19 times higher than PS only • AC can activate PS to accelerate the decomposition and mineralization of PFOA. • With AC/PS, a lower reaction temperature and a shorter reaction time would suffice • A 2-cycle schematic reaction mechanism was proposed to describe PS oxidation of PFOA. -- Abstract: Treatment of persistent perfluorooctanoic acid (PFOA) in water using persulfate (PS) oxidation typically requires an elevated temperature or UV irradiation, which is energy-consuming. Under relatively low temperatures of 25–45 °C, activated carbon (AC) activated PS oxidation of PFOA was evaluated for its potential of practical applications. With presence of AC in PS oxidation, PFOA removal efficiency at 25 °C reached 682% with a high defluorination efficiency of 549% after 12 h and few intermediates of short-chain perfluorinated carboxylic acids (PFCAs) were found. The removal and defluorination rates with the combined AC/PS system were approximately 12 and 19 times higher than those of the PS-only system, respectively. Activated carbon not only removes PFOA through adsorption, but also activates PS to form sulfate radicals that accelerate the decomposition and mineralization of PFOA. The activation energy for PS oxidation of PFOA was reduced from 668 to 261 kJ/mol by the catalytic effect of AC, which implies a lower reaction temperature and a shorter reaction time would suffice. A 2-cycle schematic reaction mechanism was used to describe PS oxidation of PFOA with the generation of various intermediates and end-products.

  17. Chemical properties of tannic extracts from bark of Pinus oocarpa and their use as adhesive

    Directory of Open Access Journals (Sweden)

    Michel Cardoso Vieira

    2014-03-01

    Full Text Available This work evaluated the properties of aqueous extracts obtained from the bark of Pinus oocarpa under addition of sodium sulfite and sodium bisulfite and the possibility of employment of tannins from the bark as an adhesive for bonding wood. After evaluation of the chemical properties of tannic extracts it was decided to employ the extraction with distilled water under addition of / 5% sodium sulfite to prepare for the tannin-formaldehyde adhesive. Adhesive phenol formaldehyde and urea-formaldehyde were modified with 10% tannin Pinus oocarpa and the effect of this addition on the quality of the adhesive was evaluated. The addition from the bark of Pinus oocarpa showed that it is possible to use pure tannin as an adhesive because of its good gluing characteristics. The addition of tannic extract to synthetic adhesives contributed to increase viscosity values. Thus the substitution of synthetic adhesives by tannins is possible only up to 10%.

  18. Wormlike micelles in mixed amino acid surfactant/nonionic surfactant aqueous systems and the effect of added electrolytes.

    Science.gov (United States)

    Shrestha, Rekha Goswami; Rodriguez-Abreu, Carlos; Aramaki, Kenji

    2009-01-01

    The formation of viscoelastic wormlike micelles in mixed amino acid surfactant/nonionic surfactant aqueous systems in the presence of different counterions and salts is reported, and the effects of the different electrolytes on the rheological behavior are discussed. N-dodecanoylglutamic acid (LAD) is neutralized with biologically relevant L-lysine and L-arginine to obtain anionic surfactants (LAD-Lys2, LAD-Arg2) which form aqueous micellar solutions at 25 degrees C. Addition of a nonionic surfactant, tri-ethyleneglycol mono n-tetradecyl ether (C14EO3), to the aqueous solutions of both LAD-Lys2 and LAD-Arg2 causes the zero-shear viscosity (eta(0)) to increase with C14EO3 concentration gradually at first, and then sharply, indicating one-dimensional growth of the aggregates and eventual formation of entangled wormlike micelles. Further addition of C14EO3 ultimately leads to phase separation of liquid crystals. Such a phase separation, which limits the maximum attainable viscosity, takes place at lower C14EO3 concentrations for LAD-Lys2 compared to LAD-Arg2 systems. It was found that the rheological behavior of micellar solutions is significantly affected by the addition of Na+X(-) salts (X = Cl(-), Br(-), I(-), NO3(-)). The maximum viscosities obtained for the systems with added salt are all higher than that of the salt-free system, and the onset of wormlike micelle formation shift towards lower nonionic surfactant concentrations upon addition of electrolyte. The maximum attainable thickening effect of anions increases in the order NO3(-)>I(-)>Br(-)>Cl(-). The effect of temperature was also investigated. Phase separation takes place at certain temperature, which depends on the type of anion in the added salt, and decreases in the order I(-)>NO3(-)>Br(-) approximately equal Cl(-), in agreement with Hofmeister's series in terms of amphiphile solubility. The thermoresponsive rheological behavior was also found to be highly dependent on the type of anion, and anomalous

  19. Adding silver and copper to hydrogen peroxide and peracetic acid in the disinfection of an advanced primary treatment effluent.

    Science.gov (United States)

    Orta De Velásquez, M T; Yáñez-Noguez, I; Jiménez-Cisneros, B; Luna Pabello, V M

    2008-11-01

    This paper evaluates the efficacy of hydrogen peroxide (HP) and peracetic acid (PAA) in the disinfection of an Advanced Primary Treatment (APT) effluent, and how said disinfection capacities can be enhanced by combining the oxidants with copper (Cu2+) and silver (Ag). The treatment sequence consisted of APT (adding chemicals to water to remove suspended solids by coagulation and flocculation), followed by disinfection with various doses of HP, HP+Cu2+, HP+Ag, PAA and PAA+Ag. Microbiological quality was determined by monitoring concentrations of fecal coliforms (FC), pathogenic bacteria (PB) and helminth eggs (HE) throughout the sequence. The results revealed that APT effluent still contains very high levels of bacteria as the treatment only removes 1-2 log of FC and PB, but the reduction in the number of viable helminth eggs was 83%. Subsequent disinfection stages demonstrated that both HP+Cu2+ and HP+Ag have a marked disinfection capacity for bacteria (3.9 and 3.4 log-inactivation, respectively). Peracetic acid on its own was already extremely efficient at disinfecting for bacteria, and the effect was enhanced when combining PAA with silver (PAA+Ag). The best result for HE removal was achieved by combining PAA with silver (PAA+Ag) at doses of 20 + 2.0 mg l(-1), respectively. The study concluded that the PAA+Ag and HP+Ag combinations were good alternatives for APT effluent disinfection, because the disinfected effluents met the standards in NOM-001-SEMARNAT-1996, Mexico's regulation governing the microbiological quality required in treated wastewater destined for unrestricted reuse in agricultural irrigation (< or =1 helminths per litre). Combining either of these disinfection treatments with a primary method such as APT, therefore, offers an effective and practical way of reducing the health risks normally associated with the reuse of wastewaters.

  20. Effect of fluoride varnish with added casein phosphopeptide-amorphous calcium phosphate on the acid resistance of the primary enamel.

    Science.gov (United States)

    Tuloglu, Nuray; Bayrak, Sule; Tunc, Emine Sen; Ozer, Fusun

    2016-09-26

    This study aimed to investigate the effects of a fluoride varnish with added Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) treatments on acid resistance of primary teeth enamel. Enamel specimens obtained from 40 primary incisors (for surface microhardness testing) and 40 primary molars (for demineralization depth measurement) were randomly divided into four groups (n = 10 incisors and 10 molars) each according to surface treatment: no treatment (control), MI varnish (1-8 % sodium fluoride and 1-5 % CPP-ACP), Clinpro White (1-5 % sodium fluoride and fluoride). Specimens were stored for 24 h in a moist environment. After varnish residues were removed, specimens were subjected to pH cycling. The effects of fluoride varnishes were evaluated according to surface microhardness, lesion depth and structural changes. Results were analyzed by ANOVA and Tukey's tests. The lowest changes in surface microhardness and lesion depth occurred in MI varnish group, followed by the Clinpro White, Duraphat and no treatment (control) group (for percentage of loss surface microhardness -20.80, -34.60, -57.80 and -73.40; for lesion depth values 23.60 μm ± 3.36, 29.85 μm ± 3.27, 40.37 μm ± 3.41 and 54.56 μm ± 4.16, respectively). Statistically significant differences in both surface microhardness and lesion depth were observed among all groups (P fluoride varnish containing CPP-ACP was more effective in increasing the acid resistance of primary enamel than other fluoride varnishes. However, further clinical research is needed to confirm these in vitro results.

  1. Biomineralization behavior of a vinylphosphonic acid-based copolymer added with polymerization accelerator in simulated body fluid

    Directory of Open Access Journals (Sweden)

    Ryo Hamai

    2015-12-01

    Full Text Available Apatite-polymer composites have been evaluated in terms of its potential application as bone substitutes. Biomimetic processes using simulated body fluid (SBF are well-known methods for preparation of such composites. They are reliant on specific functional groups to induce the heterogeneous apatite nucleation and phosphate groups possess good apatite-forming ability in SBF. Improving the degree of polymerization is important for obtaining phosphate-containing polymers, because the release of significant quantities of monomer or low molecular weight polymers can lead to suppression of the apatite formation. To date, there have been very few studies pertaining to the effect of adding a polymerization accelerator to the polymerization reaction involved in the formation of these composite materials under physiological conditions. In this study, we have prepared a copolymer from triethylene glycol dimethacrylate and vinylphosphonic acid (VPA in the presence of different amounts of sodium p-toluenesulfinate (p-TSS as a polymerization accelerator. The effects of p-TSS on the chemical durability and apatite formation of the copolymers were investigated in SBF. The addition of 0.1–1.0 wt% of p-TSS was effective for suppressing the dissolution of the copolymers in SBF, whereas larger amount had a detrimental effect. A calcium polyvinylphosphate instead of the apatite was precipitated in SBF.

  2. High dietary consumption of trans fatty acids decreases brain docosahexaenoic acid but does not alter amyloid-beta and tau pathologies in the 3xTg-AD model of Alzheimer's disease.

    Science.gov (United States)

    Phivilay, A; Julien, C; Tremblay, C; Berthiaume, L; Julien, P; Giguère, Y; Calon, F

    2009-03-03

    Dietary consumption of trans fatty acids (TFA) has increased during the 20th century and is a suspected risk factor for cardiovascular diseases. More recently, high TFA intake has been associated with a higher risk of developing Alzheimer's disease (AD). To investigate the impact of TFA on an animal model genetically programmed to express amyloid-beta (Abeta) and tau pathological markers of AD, we have fed 3xTg-AD mice with either control (0% TFA/total fatty acid), high TFA (16% TFA) or very high TFA (43% TFA) isocaloric diets from 2 to 16 months of age. Effects of TFA on plasma hepatic enzymes, glucose and lipid profile were minimal but very high TFA intake decreased visceral fat of non-transgenic mice. Importantly, dietary TFA increased brain TFA concentrations in a dose-related manner. Very high TFA consumption substantially modified the brain fatty acid profile by increasing mono-unsaturated fatty acids and decreasing polyunsaturated fatty acids (PUFA). Very high TFA intake induced a shift from docosahexaenoic acid (DHA, 22:6n-3) toward n-6 docosapentaenoic acid (DPA, 22:5n-6) without altering the n-3:n-6 PUFA ratio in the cortex of both control and 3xTg-AD mice. Changes in levels of Abeta(40), Abeta(42), tau protein, phosphorylated tau protein and synaptic markers were not statistically significant in the three groups of 3xTg-AD mice, despite a trend toward decreased insoluble tau in very high TFA-fed 3xTg-AD animals. In summary, TFA intake modulated brain fatty acid profiles but had no significant effect on major brain neuropathological hallmarks of AD in an animal model.

  3. The effect of adding urea, manganese and linoleic acid to wheat straw and wood chips on lignin degradation by fungi and subsequent

    NARCIS (Netherlands)

    Kuijk, van S.J.A.; Sonnenberg, A.S.M.; Baars, J.J.P.; Hendriks, W.H.; Cone, J.W.

    2016-01-01

    The aim of this study was optimizing Ceriporiopsis subvermispora and Lentinula edodes pre-treatment of wheat straw and wood chips by adding urea, manganese and linoleic acid. Optimization was defined as more lignin degradation and an increase in in vitro gas produ

  4. Influence of organic acids or fermentable carbohydrates on feeding value of urea treated wheat straw for Nili-Ravi buffalo bulls fed ad libitum diets

    Directory of Open Access Journals (Sweden)

    Wang-Shik Lee

    2010-02-01

    Full Text Available Four Nili-Ravi Buffalo bulls were used to study the influence of urea treated wheat straw (UTWS ensiled with organic acids or fermentable carbohydrates on nutrients digestibility and nitrogen (N balance. Four diets each having 50% dry matter (DM from UTWS ensiled with acetic acid (AD, formic acid (FD, acidified molasses (MD or corn steep liquor (CD were fed to ruminally cannulated bulls in a 4×4 Latin square design. Higher ruminal ammonia N at 3 and 6 h post prandial was observed with AD and FD diets. However, at 12 h post parandial, ammonia N was higher with MD and CD diets. The digestibility was similar across all treatments. The N balance was higher in bulls fed CD and MD diets than those fed AD and FD diets. Ensiling UTWS with fermentable carbohydrates compared to organic acids increases the N fixation in the matrix of cell wall fiber thus slowing its release at ruminal level that enhanced the N synchronization with carbon skeleton (fiber fermentation and this consequently minimizes N loss from the rumen. These results indicate that the UTWS ensiled with fermentable carbohydrates is of better feeding value for ruminants than UTWS ensiled with organic acids.

  5. Bioconversion of α-linolenic acid into n-3 long-chain polyunsaturated fatty acid in hepatocytes and ad hoc cell culture optimisation.

    Directory of Open Access Journals (Sweden)

    Ramez Alhazzaa

    Full Text Available This study aimed to establish optimal conditions for a cell culture system that would allow the measurement of 18:3n-3 (ALA bioconversion into n-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA, and to determine the overall pathway kinetics. Using rat hepatocytes (FaO as model cells, it was established that a maximum 20:5n-3 (EPA production from 50 µM ALA initial concentration was achieved after 3 days of incubation. Next, it was established that a gradual increase in the ALA concentration from 0 up to 125 µM lead to a proportional increase in EPA, without concomitant increase in further elongated or desaturated products, such as 22:5n-3 (DPA and 22:6n-3 (DHA in 3 day incubations. Of interest, ALA bioconversion products were observed in the culture medium. Therefore, in vitro experiments disregarding the medium fatty acid content are underestimating the metabolism efficiency. The novel application of the fatty acid mass balance (FAMB method on cell culture system (cells with medium enabled quantifying the apparent enzymatic activities for the biosynthesis of n-3 LC-PUFA. The activity of the key enzymes was estimated and showed that, under these conditions, 50% (Km of the theoretical maximal (V max = 3654 µmol.g(-1 of cell protein.hour(-1 Fads2 activity on ALA can be achieved with 81 µM initial ALA. Interestingly, the apparent activity of Elovl2 (20:5n-3 elongation was the slowest amongst other biosynthesis steps. Therefore, the possible improvement of Elovl2 activity is suggested toward a more efficient DHA production from ALA. The present study proposed and described an ad hoc optimised cell culture conditions and methodology towards achieving a reliable experimental platform, using FAMB, to assist in studying the efficiency of ALA bioconversion into n-3 LC-PUFA in vitro. The FAMB proved to be a powerful and inexpensive method to generate a detailed description of the kinetics of n-3 LC-PUFA biosynthesis enzymes activities in vitro.

  6. Reason analysis of sulfuric acid reduction in sulfuric acid storage tank of acid-adding system and modification measures thereof%加酸系统硫酸减少的原因分析和改进措施

    Institute of Scientific and Technical Information of China (English)

    靳晋陵

    2013-01-01

    针对某电厂工业水系统停运期间发生加酸系统硫酸自动进入压力混合器造成硫酸储罐内的硫酸减少的事件,从系统流程、现场布置、设备状况等方面分析事故产生的根源.分析结果表明,工业水系统发生“回流”导致压力混合器产生“真空”进而引发加酸管路发生“虹吸”是造成储罐内硫酸减少的根本原因,针对事故产生的因素提出了加强设备巡检、做好加酸系统、压力混合器设备停运工作的技术措施和做好工业水停运期间全厂工业水用户的管理工作.%In view of the accident: sulfuric acid in acid-adding system automatically flowed into the pressure mixer and caused sulfuric acid reduction in the sulfuric acid storage tank which happened in a power plant during the outage period of industrial water system, the reasons that caused the said accident were analyzed from the aspects of process flow, site layout, equipment status and so on. The results showed that, the refluxing of industrial water system made pressure mixer vacuum, thus led the siphon phenomenon in acid-adding pipeline, which was the basic cause of the sulfuric acid reduction. According to the factors that may cause accident, some modification measures such as: strengthening equipment inspection, perfecting technical measures to ensure the safety of acid-adding system and pressure mixer, completing management mechamism of industrial water users during the outage period of industrial water system were proposed.

  7. Maslinic acid added to the diet increases growth and protein-turnover rates in the white muscle of rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Fernández-Navarro, Mónica; Peragón, Juan; Amores, Victoria; De La Higuera, Manuel; Lupiáñez, José Antonio

    2008-03-01

    Maslinic acid (2-alpha, 3-beta-dihydroxiolean-12-en-28-oic acid) is a triterpenoid compound present in fruit and leaves of Olea europaea that can be used as an additive in the diet of trout. The present work investigates the effects of maslinic acid on growth, protein-turnover rates and nucleic acid concentration in trout white muscle. Five groups of 180 trout of a mean body mass of 20 g were fed for 225 days with diets containing 0, 1, 5, 25 and 250 mg of maslinic acid per kg of diet. At the end of the experiment, white-muscle weight and protein-accumulation rate of trout fed with maslinic acid were higher than in control. The total content of DNA, RNA, and protein in trout fed with 25 and 250 mg of maslinic acid kg(-1) were significantly higher than in control. The protein:DNA ratio was also slightly higher than control. In the same groups of trout, fractional (K(S)) and absolute (A(S)) protein-synthesis rates increased to more than 80% over the control values while no differences were found in the fractional protein-degradation rate (K(D)). These results, similar to previous findings in liver, show that maslinic acid can act as a growth factor when added to a standard trout diet.

  8. Comment on the paper: "Crystal growth and spectroscopic characterization of Aloevera amino acid added lithium sulfate monohydrate: a non-linear optical crystal".

    Science.gov (United States)

    Srinivasan, Bikshandarkoil R

    2015-01-05

    The title paper (Manimekalai et al., 2014) reports a slow evaporation solution growth of a so called 'Aloevera amino acid added lithium sulfate monohydrate' (AALSMH) crystal. In this communication, many points of criticism, concerning the crystal growth, NMR spectrum and X-ray powder pattern of this so called AALSMH nonlinear optical crystal are highlighted. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Synergy of boric acid and added salts in the catalytic dehydration of hexoses to 5-hydroxymethylfurfural in water

    DEFF Research Database (Denmark)

    Hansen, Thomas Steen; Mielby, Jerrik Jørgen; Riisager, Anders

    2011-01-01

    Boric acid and salts showed a synergistic effect on the dehydration of concentrated aqueous sugar solutions to yield 5-hydroxymethylfurfural.......Boric acid and salts showed a synergistic effect on the dehydration of concentrated aqueous sugar solutions to yield 5-hydroxymethylfurfural....

  10. The Effect of Coenzyme Q10 and Lipoic Acid Added to the Feed of Hens on Physical Characteristics of Eggs

    Directory of Open Access Journals (Sweden)

    Dušan Terčič

    2011-10-01

    Full Text Available This study was designed to investigate whether inclusions of coenzyme Q10, alpha lipoic acid and their combination into diets of hens improve egg quality characteristics. Forty-eight, 33 weeks old Lohmann Brown hens were assigned randomly to four groups of 12 hens each and fed either a basal diet or basal diet supplemented with 2 g/kg coenzyme Q10, 0.4 g/kg alpha lipoic acid and 2 g/kg coenzyme Q10 plus 0.4 g/kg alpha lipoic acid. The diets were fed for 12 weeks. Eggs were weekly examined for interior or exterior quality characteristics. There were no effects of dietary treatments on egg shape index. Coenzyme Q10 supplementation resulted in a reduction in egg shell colour (darker shells and yolk colour (paler yolks and higher incidence of blood and meat spots, which reduce the internal quality of the egg. Alpha lipoic acid had no effect on egg weight, egg shell colour, egg shell density, egg shell weight, egg shell thickness, yolk colour, incidence of blood and meat spots but increased shell strength, albumen height and Haugh units values were noted. Egg shell strength for hens supplemented with alpha lipoic acid was greater than for control hens. The results of the experiment indicated that alpha lipoic acid supplementation to the diet of layers may be of practical value due to the increased egg shell strength and better albumen characteristics without any adverse effect on other egg quality traits.

  11. Effect of cooking on the chemical composition of low-salt, low-fat Wakame/olive oil added beef patties with special reference to fatty acid content.

    Science.gov (United States)

    López-López, I; Cofrades, S; Cañeque, V; Díaz, M T; López, O; Jiménez-Colmenero, F

    2011-09-01

    Changes in chemical composition, with special reference to fatty acids, as affected by cooking, were studied in low-salt (0.5%)/low-fat patties (10%) with added Wakame (3%) and partial or total replacement of pork backfat with olive oil-in-water emulsion. The addition of Wakame and olive oil-in-water emulsion improved (P cooking retention values of moisture, fat, fatty acids and ash, which were close to 100%. Partial and total replacement of animal fat with olive oil-in-water emulsion reduced (P cooked patties was affected by product formulation. Unlike the case of all animal fat patties, when olive oil was added the cooking process increased (P Cooked formulated patties with seaweed and partial or total replacement of pork backfat by oil-in-water emulsion and with seaweed added were less calorie-dense and had lower SFAs levels, while samples with olive oil had higher MUFAs levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. Effects of non-ionic surfactants on the interactions between cellulases and tannic acid

    DEFF Research Database (Denmark)

    Olsen, Søren Nymand; Bohlin, Christina Helena; Murphy, Leigh

    2011-01-01

    Addition of non-ionic surfactants (NIS) is known to accelerate enzymatic lignocellulose hydrolysis. The mechanism behind this accelerating effect is still not elucidated but has been hypothesized to originate from favorable NIS–lignin interactions which alleviate non-productive adsorption...

  13. Production of a value added compound from the H-acid waste water-Bioflocculants by Klebsiella pneumoniae.

    Science.gov (United States)

    Zhong, Chunying; Xu, Aihua; Wang, Buyun; Yang, Xianghui; Hong, Wentao; Yang, Baokun; Chen, Changhong; Liu, Hongtao; Zhou, Jiangang

    2014-10-01

    A novel strain (designated as ZCY-7) which could convert H-acid into bioflocculants was isolated from H-acid wastewater sludge. Conditions for bioflocculants production were optimized by response surface methodology (RSM) and determined to be inoculum size 9.65%, initial pH 7.0, and CODCr of the H-acid wastewater 520mg/L. The highest flocculating efficiency achieved for kaolin suspension was 95.1%, after 60h cultivation. The yielded bioflocculant was mainly composed of polysaccharide (82.4%) and protein (14.2%), and maintained its flocculating activity in 0.4% (w/w) kaolin suspensions over pH 2-8 and 20-80°C. Fourier transform infrared (FTIR) spectra showed that amino, amide and hydroxyl groups were present in the bioflocculant molecules. A viable alternative treatment technology of H-acid wastewater using this novel strain is suggested, which could largely reduce bioflocculants costs. In addition, flocculating mechanism investigation reveals that the bioflocculant could cause kaolin suspension instability by means of charge neutralization firstly and then promoted the aggregation of suspension particles by adsorption and bridge. It is evident from the results that H-acid wastewater could be used as a source to manufacture bioflocculants. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Bacterial and protozoal communities and fatty acid profile in the rumen of sheep fed a diet containing added tannins.

    Science.gov (United States)

    Vasta, Valentina; Yáñez-Ruiz, David R; Mele, Marcello; Serra, Andrea; Luciano, Giuseppe; Lanza, Massimiliano; Biondi, Luisa; Priolo, Alessandro

    2010-04-01

    This study evaluated the effects of tannins on ruminal biohydrogenation (BH) due to shifts in the ruminal microbial environment in sheep. Thirteen lambs (45 days of age) were assigned to two dietary treatments: seven lambs were fed a barley-based concentrate (control group) while the other six lambs received the same concentrate with supplemental quebracho tannins (9.57% of dry matter). At 122 days of age, the lambs were slaughtered, and the ruminal contents were subjected to fatty acid analysis and sampled to quantify populations of Butyrivibrio fibrisolvens, which converts C(18:2) c9-c12 (linoleic acid [LA]) to C(18:2) c9-t11 (rumenic acid [RA]) and then RA to C(18:1) t11 (vaccenic acid [VA]); we also sampled for Butyrivibrio proteoclasticus, which converts VA to C(18:0) (stearic acid [SA]). Tannins increased (P tannin-free diet. The concentration of SA was not affected by tannins. The SA/VA ratio was lower (P tannin-fed lambs than for the controls, suggesting that the last step of the BH process was inhibited by tannins. The B. proteoclasticus population was lower (-30.6%; P tannin-supplemented diet than in controls. These results suggest that quebracho tannins altered BH by changing ruminal microbial populations.

  15. Analytical, ultrastructural, autoradiographic and biochemical studies on [3H]dicarboxylic acid added to cultures of melanoma cells.

    Science.gov (United States)

    Ward, B J; Breathnach, A S; Robins, E J; Bhasin, Y; Ethridge, L; Passi, S; Nazzaro-Porro, M

    1984-07-01

    Lentigo maligna and malignant melanoma can be treated by dicarboxylic acids (C9 and C12), which are competitive inhibitors of tyrosinase. We therefore studied the intracellular location and possible sites of action of dodecanedioic acid (C12) in murine melanoma cells, using EM autoradiography and biochemical analysis of lipid extracts by HPLC. Significant levels of radioactivity were found in the mitochondria and in the nuclei but not in association with membranes of rough endoplasmic reticulum, Golgi-associated endoplasmic reticulum, or Golgi apparatus, and not in coated vesicles or melanosomes. Biochemical analysis revealed that the diacid underwent beta-oxidation, which occurs only in mitochondria. The results suggest that the toxicity of dicarboxylic acids in melanoma cells is not related to anti-tyrosinase activity but may be due to interference with oxidoreductase enzymes in the mitochondria and possibly to inhibition of DNA synthesis in the nucleus.

  16. Production of a value-added hydroxy fatty acid, 7,10-dihydroxy-8(E)-octadecenoic acid from high oleic safflower oil by Pseudomonas aeruginosa PR3

    Science.gov (United States)

    Hydroxy fatty acids (HFA), originally found in small amount mainly from plant systems, are good examples of the structurally modified lipids, rendering special properties such as higher viscosity and reactivity compared to normal fatty acids. Based on these properties, HFAs possess high industrial ...

  17. Preparation of value-added metal-organic frameworks (MOFs) using waste PET bottles as source of acid linker

    CSIR Research Space (South Africa)

    Dyosiba, Xoliswa

    2016-12-01

    Full Text Available Metal-organic frameworks (MOFs) have been considered with various novel applications and the development of cost-effective processes is essential for further practices. In this work, waste PET bottles were demonstrated as the source of acid linker...

  18. Thermal and mechanical properties of polylactic acid (PLA) and bagasse carboxymethyl cellulose (CMCB) composite by adding isosorbide diesters

    Science.gov (United States)

    Kamthai, Suthaphat; Magaraphan, Rathanawan

    2015-05-01

    An isosorbide diesters is one of isororbide types used as a plasticizer. The influence of this plasticizer on thermal and mechanical properties of polylactic acid and bagasse carboxymethyl cellulose (PLA/CMCB) composites was studied. PLA was blended with CMCB at 1%wt using various contents of isosorbide diesters (5, 10, 15 and 20%wt of PLA). The differential scanning calorimetric (DSC) and thermogravimetric (TGA) analyses indicated that the increment of isosorbide diesters concentration resulted in decreasing glass transition, melting and decomposition temperatures, as well as the reduction of storage modulus of PLA/CMCB composites. Moreover, the elongation of PLA/CMCB composites was significantly improved with increasing plasticizer content.

  19. The electrooxidation mechanism of formic acid on platinum and on lead ad-atoms modified platinum studied with the kinetic isotope effect

    Science.gov (United States)

    Bełtowska-Brzezinska, M.; Łuczak, T.; Stelmach, J.; Holze, R.

    2014-04-01

    Kinetics and mechanism of formic acid (FA) oxidation on platinum and upd-lead ad-atoms modified platinum electrodes have been studied using unlabelled and deuterated compounds. Poisoning of the electrode surface by CO-like species was prevented by suppression of dissociative chemisorption of FA due to a fast competitive underpotential deposition of lead ad-atoms on the Pt surface from an acidic solution containing Pb2+ cations. Modification of the Pt electrode with upd lead induced a catalytic effect in the direct electrooxidation of physisorbed FA to CO2. With increasing degree of H/D substitution, the rate of this reaction decreased in the order: HCOOH > DCOOH ≥ HCOOD > DCOOD. HCOOH was oxidized 8.5-times faster on a Pt/Pb electrode than DCOOD. This primary kinetic isotope effect proves that the C-H- and O-H-bonds are simultaneously cleaved in the rate determining step. A secondary kinetic isotope effect was found in the dissociative chemisorption of FA in the hydrogen adsorption-desorption range on a bare Pt electrode after H/D exchange in the C-H bond, wherein the influence of deuterium substitution in the O-H group was negligibly small. Thus the C-H bond cleavage is accompanied by the C-OH and not the O-H bond split in the FA decomposition, producing CO-like species on the Pt surface sites.

  20. Luminescence features from conical bubble collapse in 1,2 propanediol and its perturbation adding sulfuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Navarrete, M; Godinez, F A [Universidad Nacional Autonoma de Mexico, Ciudad Universitaria No. 3000, Col. Copilco Universidad, Delegacion de Coyoacan, Mexico, D. F. Codigo Postal 04360, Instituto de Ingenieria, Lab. de Fotofisica (Mexico); Sanchez, C [Universidad Nacional Autonoma de Mexico, Ciudad Universitaria No. 3000, Col. Copilco Universidad, Delegacion de Coyoacan, Mexico, D. F. Codigo Postal 04360, Lab. de Fotonica y Microondas (Mexico); Mejia, E V; Villagran, M, E-mail: mnm@pumas.iingen.unam.mx [Universidad Nacional Autonoma de Mexico, Ciudad Universitaria No. 3000, Col. Copilco Universidad, Delegacion de Coyoacan, Mexico, D. F. Codigo Postal 04360 (Mexico)

    2011-01-01

    A summary of experimental findings on the luminescence from bubble collapse, CBL, varying the gas inert bubble content, the driving pressure and perturbing the liquid piston with small quantities of sulfuric acid is presented. The temporal, spectral, and spatial characteristics of the luminescence regarding with dynamic features of collapse are also examinees. CBL was reproduced using Argon gas, and 1, 2-propanediol as liquid piston. In general, the pulse shape exhibits a large variety of profiles. The luminescence intensity was increased two-fold and the pulse width decreased almost to half when the liquid was disturbed with sulfuric acid. Spectrally, the Swan, CH and CN lines were observed at low volume of Ar gas and low driving pressure, lines of OH{sup 0}, Na*, K* always appear superimposed on an underlying continuum background. De-excitation of sodium atom at 589 nm and two satellites diffuse bands at {approx}554 nm and {approx}620 nm from alkali-metal-argon exciplexes was observed in both systems under certain conditions. All these findings point towards several sources of light emission that are generated during the compression time line, resulting in temporally and spatially inhomogeneous pulse. A mechanism for explain the bright CBL is broached.

  1. Development and quality of a Brazilian semi-hard goat cheese (coalho) with added probiotic lactic acid bacteria.

    Science.gov (United States)

    Garcia, Estefânia Fernandes; de Oliveira, Maria Elieidy Gomes; Queiroga, Rita de Cássia Ramos Do Egypto; Machado, Tamires Alcântara Dourado; de Souza, Evandro Leite

    2012-12-01

    The effects of the addition of different strains of lactic acid bacteria on different quality parameters of a Brazilian goat semi-hard cheese (coalho) were assessed during 7 days of storage (10°C) as follows: Control, Lactobacillus lactis subsp. lactis and L. lactis subsp. cremoris (standard); C2, L. acidophilus; C3, L. paracasei; C4, Bifidobacterium lactis; and C5, L. acidophilus, L. paracasei and B. lactis. There were no differences for the proteolysis index and depth of proteolysis among the assessed cheeses. The cheeses presented increase in hardness, gumminess and chewiness during the storage. Regarding the ability to melt, all evaluated cheeses showed a reduction in diameter. Cheeses presented high luminosity with predominance of the yellow component; and number of lactic bacteria greater than 10⁶-10⁷ cfu/g during the 7 days of storage. C5 had better sensory scores in the acceptance test, purchase intention and preference ranking test. Coalho goat cheese could be a potential carrier of probiotic lactic acid bacteria.

  2. Ad Libitum

    Index Scriptorium Estoniae

    2001-01-01

    20. mai. Segakoor Ad Libitum laulis Niguliste Muuseum-kontserdisaalis. Dirigendid Alice Pehk ja Kaie Viigipuu. Kaastegev Tiit Kiik (orel). Esitati koorimuusikat renessansist tänapäevani ning prantsuse orelimuusikat : [täistekst

  3. Novel ketone body therapy for managing Alzheimer's disease: An Editorial Highlight for Effects of a dietary ketone ester on hippocampal glycolytic and tricarboxylic acid cycle intermediates and amino acids in a 3xTgAD mouse model of Alzheimer's disease.

    Science.gov (United States)

    Puchowicz, Michelle A; Seyfried, Thomas N

    2017-03-15

    Read the highlighted article 'Effects of a dietary ketone ester on hippocampal glycolytic and tricarboxylic acid cycle intermediates and amino acids in a 3xTgAD mouse model of Alzheimer's disease' on doi: 10.1111/jnc.13958.

  4. Omega 3 fatty acids induce a marked reduction of apolipoprotein B48 when added to fluvastatin in patients with type 2 diabetes and mixed hyperlipidemia: a preliminary report

    Directory of Open Access Journals (Sweden)

    González-Santos Pedro

    2009-01-01

    Full Text Available Abstract Backgorund Mixed hyperlipidemia is common in patients with diabetes. Statins, the choice drugs, are effective at reducing lipoproteins that contain apolipoprotein B100, but they fail to exert good control over intestinal lipoproteins, which have an atherogenic potential. We describe the effect of prescription omega 3 fatty acids on the intestinal lipoproteins in patients with type 2 diabetes who were already receiving fluvastatin 80 mg per day. Methods Patients with type 2 diabetes and mixed hyperlipidemia were recruited. Fasting lipid profile was taken when patients were treated with diet, diet plus 80 mg of fluvastatin and diet plus fluvastatin 80 mg and 4 g of prescription omega 3 fatty acids. The intestinal lipoproteins were quantified by the fasting concentration of apolipoprotein B48 using a commercial ELISA. Results The addition of 4 g of prescription omega 3 was followed by significant reductions in the levels of triglycerides, VLDL triglycerides and the triglyceride/HDL cholesterol ratio, and an increase in HDL cholesterol (P Conclusion Our preliminary findings therefore suggest an additional benefit on postprandial atherogenic particles when omega 3 fatty acids are added to standard treatment with fluvastatin.

  5. Adding Ajax

    CERN Document Server

    Powers, Shelley

    2007-01-01

    Ajax can bring many advantages to an existing web application without forcing you to redo the whole thing. This book explains how you can add Ajax to enhance, rather than replace, the way your application works. For instance, if you have a traditional web application based on submitting a form to update a table, you can enhance it by adding the capability to update the table with changes to the form fields, without actually having to submit the form. That's just one example.Adding Ajax is for those of you more interested in extending existing applications than in creating Rich Internet Applica

  6. 添加丙酸和乳酸菌对杂交狼尾草青贮发酵品质的影响%Effect of adding propionic acid and lactic acid bacteria on fermentation quality of hybrid Pennisetum silage

    Institute of Scientific and Technical Information of China (English)

    王雁; 张新全; 杨富裕

    2012-01-01

    研究丙酸、乳酸茵和两者组合不同添加水平对杂交狼尾草(Pennisetum americanum×P.purpereurn)青贮发酵品质的影响。试验设对照(无添加)、乳酸菌(LAB)、0.2%丙酸、0.3%丙酸、0.4%丙酸、0.5%丙酸、0.2%丙酸+乳酸菌、0.3%丙酸+乳酸菌、0.4%丙酸+乳酸菌、0.5%丙酸+乳酸菌(占鲜质量比例)处理,青贮45d后开袋分析。结果表明,添加丙酸可以有效改善杂交狼尾草的青贮品质,最佳添加量为0.3%;添加乳酸茵有助于提高杂交狼尾草的有氧稳定性。%The experiment was conducted to investigate the effects of adding propionic acid, lactic acid bacteria and mixture of the two additions on the fermentation quality of hybrid Pennisetum silage. There were treatments as following, the control (no addition), Lactic acid bacteria addition (LAB), Propionic acid addition at 0. 2% (PA0.2), Propionic acid addition at 0. 3% (PA0.3), Propionic acid addition at 0. 4% (PR0. 4), Propionic acid addition at 0.5% (PA0.5), PA0.2 +LAB, PA0.3 +LAB, PA0.4 +LAB and PA0.5 +LAB (FM,%). After 45 days of ensiling, the ensiled forages were sampled and analyzed. The results showed that addition propionic acid could improve the fermentation quality of hybird P. silages, and adding Propionic acid at a rate of 0. 3% is the optimum for fermentation quality of hybrid Pennisetum.

  7. Studies on ice core records of dicarboxylic acids, ω-oxocarboxylic acids, pyruvic acid, α-dicarbonyls and fatty acids from southern Alaska since 1665 AD : A link to climate change in the Northern Hemisphere

    OpenAIRE

    Pokhrel, Ambarish

    2015-01-01

    Alaskan ice core (180 m long, 343 years) has been analyzed for a homologous series of normal (C2 - C11), branched chain (iC4 - iC6), unsaturated (maleic, fumaric, methylmaleic and phthalic), multifunctional dicarboxylic (malic, oxomalonic and 4- oxopimelic), ω-oxocarboxylic acids (ωC2 - ωC9), pyruvic acid, glyoxal and methylglyoxal using gas chromatography (GC/FID) and GC/mass spectrometry (GC/MS) to understand historical changes in water soluble organic aerosols. Similarly,...

  8. Action of human group IIa secreted phospholipase A2 on cell membranes. Vesicle but not heparinoid binding determines rate of fatty acid release by exogenously added enzyme.

    Science.gov (United States)

    Koduri, R S; Baker, S F; Snitko, Y; Han, S K; Cho, W; Wilton, D C; Gelb, M H

    1998-11-27

    Human group IIa phospholipase A2 (hIIa-PLA2) is a highly basic protein that is secreted from a number of cells during inflammation and may play a role in arachidonate liberation and in destruction of invading bacteria. It has been proposed that rodent group IIa PLA2 is anchored to cell surfaces via attachment to heparan sulfate proteoglycan and that this interaction facilitates lipolysis. hIIa-PLA2 contains 13 lysines, 2 histidines, and 10 arginines that fall into 10 clusters. A panel of 26 hIIa-PLA2 mutants were prepared in which 1-4 basic residues in each cluster were changed to glutamate or aspartate (charge reversal). A detailed analysis of the affinities of these mutants for anionic vesicles and for heparin and heparan sulfate in vitro and of the specific activities of these proteins for hydrolysis of vesicles in vitro and of living cell membranes reveal the following trends: 1) the affinity of hIIa-PLA2 for heparin and heparan sulfate is modulated not by a highly localized site of basic residues but by diffuse sites that partially overlap with the interfacial binding site. In contrast, only those residues on the interfacial binding site of hIIa-PLA2 are involved in binding to membranes; 2) the relative ability of these mutants to hydrolyze cellular phospholipids when enzymes were added exogenously to CHO-K1, NIH-3T3, and RAW 264.7 cells correlates with their relative in vitro affinity for vesicles and not with their affinity for heparin and heparan sulfate. 3) The rates of exogenous hIIa-PLA2-catalyzed fatty acid release from wild type CHO-K1 cells and two mutant lines, one lacking glycosaminoglycan and one lacking heparan sulfate, were similar. Thus basic residues that modulate interfacial binding are important for plasma membrane fatty acid release by exogenously added hIIa-PLA2. Binding of hIIa-PLA2 to cell surface heparan sulfate does not modulate plasma membrane phospholipid hydrolysis by exogenously added hIIa-PLA2.

  9. Effects of large doses of arachidonic acid added to docosahexaenoic acid on social impairment in individuals with autism spectrum disorders: a double-blind, placebo-controlled, randomized trial.

    Science.gov (United States)

    Yui, Kunio; Koshiba, Mamiko; Nakamura, Shun; Kobayashi, Yuji

    2012-04-01

    Autism spectrum disorders are a neurodevelopmental disorders with reduced cortical functional connectivity relating to social cognition. Polyunsaturated fatty acids arachidonic acid (ARA) and docosahexaenoic acid (DHA) may have key role in brain network maturation. In particularly, ARA is important in signal transduction related to neuronal maturation. Supplementation with larger ARA doses added to DHA may therefore mitigate social impairment. In a 16-week, double-blind, randomized, placebo-controlled trial, we evaluated the efficacy of supplementation with large doses of ARA added to DHA (n = 7) or placebo (n = 6) in 13 participants (mean age, 14.6 [SD, 5.9] years). To examine underlying mechanisms underlying the effect of our supplementation regimen, we examined plasma levels of antioxidants transferrin and superoxide dismutase, which are useful markers of signal transduction. The outcome measures were the Social Responsiveness Scale and the Aberrant Behavior Checklist-Community. Repeated-measures analysis of variance revealed that our supplementation regimen significantly improved Aberrant Behavior Checklist-Community-measured social withdrawal and Social Responsiveness Scale-measured communication. Treatment effect sizes were more favorable for the treatment group compared with the placebo group (communication: treatment groups, 0.87 vs, placebo, 0.44; social withdrawal: treatment groups, 0.88, vs placebo, 0.54). There was a significant difference in the change in plasma transferrin levels and a trend toward a significant difference in the change in plasma superoxide dismutase levels between the 2 groups. This preliminary study suggests that supplementation with larger ARA doses added to DHA improves impaired social interaction in individuals with autism spectrum disorder by up-regulating signal transduction.

  10. Adding Value to Goat Meat: Biochemical and Technological Characterization of Autochthonous Lactic Acid Bacteria to Achieve High-Quality Fermented Sausages

    Directory of Open Access Journals (Sweden)

    Miriam T. Nediani

    2017-05-01

    Full Text Available Quality and safety are important challenges in traditional fermented sausage technology. Consequently, the development of a tailored starter culture based on indigenous microbiota constitutes an interesting alternative. In the present study, spontaneously fermented goat meat sausages were created and analyzed using a physicochemical and microbiological approach. Thereafter 170 lactic acid bacteria (LAB strains were isolated and preliminary characterized by phenotypic assays. The hygienic and technological properties, and growth and fermentative potential of isolates using a goat-meat-based culture medium were evaluated. All strains proved to have bioprotective features due to their acidogenic metabolism. Almost all grew optimally in meat environments. LAB isolates presented proteolytic activity against meat proteins and enriched amino acid contents of the goat-meat-based model. The most efficient strains were four different Lactobacillus sakei isolates, as identified by genotyping and RAPD analysis. L. sakei strains are proposed as optimal candidates to improve the production of fermented goat meat sausages, creating a new added-value fermented product.

  11. Acute effects of breakfasts containing alpha-lactalbumin, or gelatin with or without added tryptophan, on hunger, 'satiety' hormones and amino acid profiles.

    Science.gov (United States)

    Nieuwenhuizen, Arie G; Hochstenbach-Waelen, Ananda; Veldhorst, Margriet A B; Westerterp, Klaas R; Engelen, Mariëlle P K J; Brummer, Robert-Jan M; Deutz, Nicolaas E P; Westerterp-Plantenga, Margriet S

    2009-06-01

    Proteins are the most satiating macronutrients. Tryptophan (TRP) may contribute to the satiating effect, as it serves as a precursor for the anorexigenic neurotransmitter serotonin. To address the role of TRP in the satiating properties of dietary protein, we compared three different breakfasts, containing either alpha-lactalbumin (high in TRP), gelatin (low in TRP) or gelatin with added TRP (gelatin+TRP, high in TRP), on appetite. Twenty-four subjects (22-29 kg/m2; aged 19-37 years) received a subject-specific breakfast at t = 0 with 10, 55 and 35 % energy from protein, carbohydrate and fat respectively in a randomised, single-blind design. Hunger, glucagon-like peptide (GLP)-1, ghrelin, amino acid concentrations and energy intake during a subsequent lunch were determined. Suppression of hunger was stronger 240 min after the breakfast with alpha-lactalbumin compared with gelatin and gelatin+TRP. Total plasma amino acid concentrations were lower with alpha-lactalbumin compared with gelatin with or without TRP (from t = 180-240 min). TRP concentrations were higher after alpha-lactalbumin than after gelatin with or without TRP from t = 0-100 min, whereas from t = 100-240 min, TRP concentrations were lower after gelatin than after alpha-lactalbumin and gelatin+TRP. The plasma ratio of TRP to other large neutral amino acids (LNAA) was, only at t = 100 min, lower after gelatin+TRP than after the other breakfasts. Plasma amino acid responses, TRP concentrations and TRP:LNAA ratios were not correlated with hunger. GLP-1 and ghrelin concentrations were similar for all diets. Energy intake during a subsequent lunch was similar for all diets. Summarised, an alpha-lactalbumin breakfast suppresses hunger more than a gelatin or gelatin+TRP breakfast. This cannot be explained by (possible) differences found in TRP concentrations and TRP:LNAA ratios in the breakfasts and in plasma, as well as in circulating total amino acids, GLP-1 and ghrelin.

  12. Laying hens can convert high doses of folic acid added to the feed into natural folates in eggs providing a novel source of food folate.

    Science.gov (United States)

    Hoey, Leane; McNulty, Helene; McCann, Elizabeth M E; McCracken, Kelvin J; Scott, John M; Marc, Barbara Blaznik; Molloy, Anne M; Graham, Ciaren; Pentieva, Kristina

    2009-01-01

    There are few good sources of natural food folates apart from green leafy vegetables and these may have a limited potential to increase folate status because of substantial losses that can occur during cooking. Fortified foods can overcome this but are controversial because of safety concerns regarding chronic exposure to high-dose folic acid (FA; the synthetic form). The aim of the present study was to develop eggs with an enriched natural folate content and minimal unmetabolised FA. Forty-eight, 30-week-old laying hens were randomised to receive the basal feed (formulated to provide 1 mg folate/kg feed) to which had been added one of the following FA levels (0, 2, 4, 8, 16, 32 mg/kg feed). Total folate was measured in eggs collected throughout the 12-week study period and the FA content estimated at 12 weeks. Results showed that the maximal egg folate content was achieved by adding 16 mg FA/kg feed. At this optimal dose, the total folate content per egg was 75 microg (compared with 32 microg in a regular egg) of which FA represented at most 10%, a level which would probably be converted into natural folates by humans after ingestion. The results demonstrate that it is possible to use synthetic FA at high doses to produce novel animal foods enriched with natural folates in a cost-efficient process. Such foods may be particularly relevant to European populations without access to FA fortification and therefore dependent on natural food folate sources for the primary prevention of folate-related disease.

  13. Development of alcoholic and malolactic fermentations in highly acidic and phenolic apple musts.

    Science.gov (United States)

    del Campo, Gloria; Berregi, Iñaki; Santos, José Ignacio; Dueñas, Maite; Irastorza, Ana

    2008-05-01

    This work reports the influence of the high acidity and high phenolic content in apple musts on the development of alcoholic and malolactic fermentations and on the final chemical and microbiological composition of the ciders. Four different musts were obtained by pressing several varieties and proportions of cider apples from the Basque Country (Northern Spain). Specially acidic and phenolic varieties were selected. Three musts were obtained in experimental stations and the fourth one, in a cider factory following usual procedures. The evolution of these musts was monitored during five months by measuring 18 parameters throughout eight samplings. In the most acidic of the three experimental musts, yeasts were added to complete the alcoholic fermentation. In the rest of the musts, alcoholic and malolactic fermentations took place spontaneously due to natural microflora and no chemical was added to control these processes. Malolactic fermentation (MLF) finished before alcoholic fermentation in the three tanks obtained in experimental stations, even in the most acidic and phenolic one (pH 3.18, 1.78 g tannic acid/l). After four months, these ciders maintained low levels of lactic acid bacteria (10(4)CFU/ml) and low content of acetic acid (cider factory, but MLF finished 10 days after alcoholic fermentation. Subsequently, this must maintained a high population of lactic acid bacteria (>10(6)CFU/ml), causing a higher production of acetic acid (>1.00 g/l) than in the other ciders. These results show the possible advantages of MLF finishing before alcoholic fermentation.

  14. Fatty acid patterns of dog erythrocyte membranes after feeding of a fish-oil based DHA-rich supplement with a base diet low in n-3 fatty acids versus a diet containing added n-3 fatty acids

    Directory of Open Access Journals (Sweden)

    Fuhrmann Herbert

    2011-10-01

    Full Text Available Abstract Background In dogs, increasing the tissue n-3 fatty acid (FA content is associated with potential benefit in some medical conditions, e.g. atopic dermatitis, cancer or heart disease. Therefore effectively and conveniently increasing tissue n-3 FA levels in dogs is of interest. Incorporation of dietary n-3 FA into cell membranes may be studied by FA analysis of erythrocyte membranes (EM, because of the correlation of its FA composition with the FA composition of other cells. Aim of the study was to determine whether an n-3 FA additive added to a control diet is as effective in increasing EM n-3 FA content as feeding an n-3 FA enriched diet. Furthermore the time course of the incorporation of dietary n-3 FA into canine EM was investigated. Methods Thirty dogs were randomly divided into three dietary groups with ten dogs per group. CONT got a dry dog food diet which did not contain EPA or DHA. FO got a dry dog food diet with a high EPA and DHA content. ADD got the CONT diet combined with an n-3 FA additive rich in DHA and EPA. After a feeding period of 12 weeks the additive was discontinued in ADD and these dogs were fed CONT diet for another four weeks to observe washout effects. Erythrocyte lipids were extracted from venous blood samples and their FA composition was determined by gas chromatography. The Mann-Whitney-U-test was used to detect significant differences between the different groups and time points. Results After one week the proportions of n-3 FA, DHA and EPA were already significantly increased in ADD and FO, apparently reaching a plateau within eight weeks. In our study DHA and not EPA was preferably incorporated into the EM. After discontinuing the administration of the additive in ADD, the n-3 FA values declined slowly without reaching baseline levels within four weeks. Conclusions In dogs, an increase of dietary n-3 FA content leads to a rapid inclusion of n-3 FA into EM, regardless of whether the n-3 FA are offered as

  15. 控制加酸量稳定中水碱度%Stabilizing Reclaimed Water Alkalinity by Controlling Quantity of Adding Acid

    Institute of Scientific and Technical Information of China (English)

    刘芹; 彭旭东

    2014-01-01

    In order to save water, usage of urban reclaimed water is expanding. At present, a lot of tech-nical personnel have studied the reclaimed water using in the technology of circulating cooling water in thermal power generation. This paper introduces how to control the adding acid quantity of the reclaimed water under the large alkalinity change and not to be accurately detected, then stabilizing the reclaimed water alkalinity.%为了节约水资源,城市中水的利用领域不断扩大。目前许多技术人员对中水在火力发电生产中用于循环冷却水技术进行了较多的研究。文章介绍了在中水碱度变化大,碱度无法在线准确检测下如何控制中水的加酸量,稳定中水的碱度。

  16. Effects of intraduodenal infusion of the branched-chain amino acid leucine on ad libitum eating, gut motor and hormone functions, and glycemia in healthy men.

    Science.gov (United States)

    Steinert, Robert E; Landrock, Maria F; Ullrich, Sina S; Standfield, Scott; Otto, Bärbel; Horowitz, Michael; Feinle-Bisset, Christine

    2015-10-01

    Branched-chain amino acids (BCAAs), particularly leucine, act as nutrient signals regulating protein synthesis and degradation as well as glucose metabolism. In addition, leucine has been demonstrated in animal experiments to modulate eating and energy homeostasis. We aimed to characterize the effects of physiologic and supraphysiologic loads of intraduodenal leucine on eating, gut hormone and motor functions, and blood glucose in humans. Twelve lean men were studied on 3 occasions in a randomized, double-blind order. Antropyloroduodenal motility, plasma ghrelin, cholecystokinin, glucagon-like peptide 1, peptide YY, insulin, glucagon, blood glucose, appetite perceptions, and gastrointestinal symptoms were measured during 90-min intraduodenal infusions of leucine at 0.15 kcal/min (total 3.3 g, 13.5 kcal), 0.45 kcal/min (total 9.9 g, 40.5 kcal), or saline (control). Ad libitum eating from a buffet lunch was quantified immediately after the infusions. Leucine at 0.45 kcal/min inhibited eating (energy intake by ∼13%, P eating are probably not primarily mediated by changes in gut motor and hormone functions, with perhaps the exception of cholecystokinin. Instead, increased plasma leucine concentrations may be a potential signal mediating the eating-inhibitory effect of leucine. The study was registered as a clinical trial with the Australia and New Zealand Clinical Trial Registry (www.anzctr.org.au) as ACTRN12613000899741. © 2015 American Society for Nutrition.

  17. Added value of smooth hypointense rim in the hepatobiliary phase of gadoxetic acid-enhanced MRI in identifying tumour capsule and diagnosing hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    An, Chansik; Han, Kyunghwa; Choi, Jin-Young; Park, Mi-Suk; Kim, Myeong-Jin [Yonsei University College of Medicine, Department of Radiology, Research Institute of Radiological Science, Seoul (Korea, Republic of); Rhee, Hyungjin [Yonsei University College of Medicine, Department of Pathology, Brain Korea 21 PLUS Project for Medical Science, Integrated Genomic Research Center for Metabolic Regulation, Seoul (Korea, Republic of); Park, Young-Nyun [Yonsei University College of Medicine, Department of Pathology, Brain Korea 21 PLUS Project for Medical Science, Integrated Genomic Research Center for Metabolic Regulation, Seoul (Korea, Republic of); Yonsei University College of Medicine, Severance Biomedical Science Institute, Seoul (Korea, Republic of); Park, Sumi [National Health Insurance Service Ilsan Hospital, Department of Radiology, Goyang (Korea, Republic of)

    2017-06-15

    To examine the added value of considering smooth hypointense rim in the hepatobiliary phase (HBP) of gadoxetic acid-enhanced MRI as capsule appearance for diagnosing tumour capsules and hepatocellular carcinoma (HCC). A total of 377 hepatic lesions (330 HCCs, 35 non-HCC malignancies and 12 benign) were included from 345 patients who underwent resection after MRI between January 2008 and December 2011. Two radiologists assessed the presence or absence of conventional capsule appearance and smooth hypointense rim in the HBP, and categorized each hepatic lesion according to the Liver Imaging Reporting and Data System. Difference in diagnostic performance was evaluated using the generalized estimating equation method. For identifying capsule, the sensitivity and accuracy of HBP hypointense rim were significantly higher than those of conventional capsule appearance (81.5 % vs. 57.8 % and 76.1 % vs. 59.4 %, respectively; P < 0.001). For diagnosing HCC, the sensitivity and accuracy of LR-5 or LR-5 V were significantly higher when the HBP hypointense rim was also considered capsule appearance (83 % vs. 72.7 % and 84.1 % vs. 75.1 %, respectively; P < 0.001), with the same specificity (91.5 %). Regarding smooth hypointense rim in the HBP as capsule appearance could improve the detection of tumour capsule and the diagnosis of HCC. (orig.)

  18. AD6 (8-monochloro-3-beta-diethylamino-ethyl-4-methyl-7-ethoxycarbonyl-meth oxy coumarin) inhibits the release of arachidonic acid in human platelets stimulated by thrombin

    Energy Technology Data Exchange (ETDEWEB)

    Porcellati, S.; Costantini, V.; Prosdocimi, M.; Pistolesi, R.; Porrovecchio, P.; Nenci, G.G.; Goracci, G.

    1987-07-01

    The coumarin derivative AD6 is known to inhibit platelet aggregation and release and it possesses vasodilatory properties on coronary arteries of laboratory animals. Furthermore, the inhibition of the production of TxB2 from endogenous substrates after stimulation of human platelets with collagen has been demonstrated. The present report demonstrates that AD6 inhibits the production of labeled arachidonic acid and diglycerides from phospholipids of platelets stimulated with thrombin. This effect is dose-dependent and is already evident at a concentration of the drug (25 microM) which is unable to prevent the aggregation. Apparently, AD6 inhibits the release of arachidonic acid from phosphatidylinositol and choline phosphoglycerides which are the main sources of the substrate for the synthesis of prostaglandins and thromboxanes.

  19. Delayed gastric emptying rate as a potential mechanism for lowered glycemia after eating sourdough bread: studies in humans and rats using test products with added organic acids or an organic salt.

    Science.gov (United States)

    Liljeberg, H G; Björck, I M

    1996-12-01

    The possible effects of organic acids or an organic salt on the rate of gastric emptying was studied to identify the cause for reduced postmeal responses of blood glucose and insulin to foods containing such components, eg, sourdough bread. Paracetamol was included in bread products with added lactic acid or sodium propionate and used as a marker for the rate of gastric emptying in healthy subjects. In parallel, postprandial glycemia, insulinemia, and satiety were evaluated. The influence of lactic acid, propionic acid, and sodium propionate was also studied in rats after they were tube-fed with glucose solutions. The bread products with lactic acid or sodium propionate both lowered blood glucose and insulin responses. The bread with sodium propionate also prolonged satiety. The reason for the lowered metabolic responses with sodium propionate was probably a lowered gastric emptying rate, as judged from reduced blood paracetamol concentrations; there was no such effect observed with bread with added lactic acid. A similar amount of lactic acid in solution tube-fed to rats did not affect the disappearance of glucose from the stomach. In contrast with the finding in humans, sodium propionate had no effect on the rate of gastric emptying in rats whereas an equimolar solution of propionic acid reduced gastric emptying rate in rats. Possibly, less of this acid was produced in the gastric contents after a bolus load of a sodium propionate solution (in rats) than in an eating situation. Also, the pH and/or the osmolarity may be important, and when provided in excessive amounts, lactic acid reduced the gastric emptying rate in rats. A hydrochloric acid solution of similar pH was much less effective in this respect.

  20. 耐盐乳酸菌添加对高盐稀态酱油风味的影响%The Impact of Adding Salt-tolerant Lactic Acid Bacteria on the Flavor of High-salt Liquid Soy Sauce

    Institute of Scientific and Technical Information of China (English)

    戚晨晨; 王猛; 沈艾彬

    2016-01-01

    In the fermentation process of high-salt liquid soy sauce,the addition of salt-tolerant lactic acid bacteria has a great influence on the final flavor components of soy sauce.Through adding salt-tolerant lactic acid bacteria on the 30th and 45th day of fermentation,research the content of total acids,saltless solids and flavor compounds.The results show that adding salt-tolerant lactic acid bacteria on the 45th day,the content of total acids,saltless solids and flavor compounds is higher than that adding and without adding salt-tolerant lactic acid bacteria on the 30th day.The research has laid a foundation for its future application in the industrial production of brewed soy sauce with good flavor.%高盐稀态酱油发酵过程中,耐盐乳酸菌的添加时间对于酱油最终风味成分的影响很大。通过分别在发酵30,45天添加耐盐乳酸菌、未添加乳酸菌发酵的酱油对照,研究总酸、无盐固形物、风味物质的含量。研究表明:发酵45天添加耐盐乳酸菌,总酸、无盐固形物、风味物质的含量均高于30天添加和未添加乳酸菌发酵的酱油对照,为其以后应用于工业生产酿造出风味良好的酱油打下基础。

  1. A study about the relevance of adding acetylsalicylic acid in primary prevention in subjects with type 2 diabetes mellitus: effects on some new emerging biomarkers of cardiovascular risk.

    Science.gov (United States)

    Derosa, Giuseppe; Mugellini, Amedeo; Pesce, Rosa M; D'Angelo, Angela; Maffioli, Pamela

    2015-07-30

    To evaluate the relevance of adding acetylsalicylic acid (ASA) in primary prevention in subjects with type 2 diabetes mellitus. 213 patients with type 2 diabetes mellitus and hypertension were randomized to amlodipine 5 mg, or amlodipine 5 mg + ASA 100 mg for 3 months (Phase A); then, if adequate blood pressure control was reached patients terminated the study; otherwise, amlodipine was up-titrated to 10 mg/day for further 3 months and compared to amlodipine 10 mg + ASA 100 mg (Phase B). We assessed at baseline, at the end of Phase A, and at the end of Phase B the levels of some new emerging biomarkers of cardiovascular risk including: high sensitivity C-reactive protein (Hs-CRP), adiponectin (ADN), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), myeloperoxidase (MPO), soluble CD40 ligand (sCDL40). Compared to baseline, at the end of Phase A, patients treated with amlodipine 5 mg + ASA 100 mg showed a statistically significant reduction of Hs-CRP (-15.0%), TNF-α (-21.7%), MPO (-9.7%), and sCDL40 (-15.7%), and a statistically significant increase of ADN (+15.0%). These values were significantly better than the ones obtained with amlodipine alone. Similarly, at the end of Phase B, amlodipine 10 mg + ASA significantly lowered Hs-CRP (-18.8%), TNF-α (-15.0%), MPO (-9.2%), and sCDL40 (-20.0%) and increased ADN (+11.8%), with a better effect compared to amlodipine alone. All biomarkers considered were significantly improved by ASA addition. These data suggest that the use of ASA in primary prevention could be useful in patients with type 2 diabetes mellitus and hypertension. ClinicalTrials.gov: NCT02064218.

  2. String Theory on AdS Spaces

    NARCIS (Netherlands)

    de Boer, J.

    2000-01-01

    In these notes we discuss various aspects of string theory in AdS spaces. We briefly review the formulation in terms of Green-Schwarz, NSR, and Berkovits variables, as well as the construction of exact conformal field theories with AdS backgrounds. Based on lectures given at the Kyoto YITP Workshop

  3. Online Ad Assignment with an Ad Exchange

    OpenAIRE

    Dvořák, Wolfgang; Henzinger, Monika

    2016-01-01

    Ad exchanges are becoming an increasingly popular way to sell advertisement slots on the internet. An ad exchange is basically a spot market for ad impressions. A publisher who has already signed contracts reserving advertisement impressions on his pages can choose between assigning a new ad impression for a new page view to a contracted advertiser or to sell it at an ad exchange. This leads to an online revenue maximization problem for the publisher. Given a new impression to sell decide whe...

  4. Aqueous thermal degradation of gallic acid

    Science.gov (United States)

    Snow Boles, Jennifer; Crerar, David A.; Grissom, Grady; Key, Tonalee C.

    1988-02-01

    Aqueous thermal degradation experiments show gallic acid, a naturally occurring aromatic carboxylic compound, decomposes rapidly at temperatures between 105° and 150°C, with an activation energy of 22.9 or 27.8 kcal/ mole, depending on pH of the starting solution. Pyrogallol is the primary product identified, indicating degradation via decarboxylation and a carbanion transition state. Relatively rapid degradation of vanillic, phthalic, ellagic and tannic acids has also been observed, suggesting that these and perhaps other aromatic acids could be short-lived in deep formation waters.

  5. Fatty acid patterns of dog erythrocyte membranes after feeding of a fish-oil based DHA-rich supplement with a base diet low in n-3 fatty acids versus a diet containing added n-3 fatty acids

    OpenAIRE

    Fuhrmann Herbert; Nielsen Leif; Stoeckel Katja; Bachmann Lisa

    2011-01-01

    Abstract Background In dogs, increasing the tissue n-3 fatty acid (FA) content is associated with potential benefit in some medical conditions, e.g. atopic dermatitis, cancer or heart disease. Therefore effectively and conveniently increasing tissue n-3 FA levels in dogs is of interest. Incorporation of dietary n-3 FA into cell membranes may be studied by FA analysis of erythrocyte membranes (EM), because of the correlation of its FA composition with the FA composition of other cells. Aim of ...

  6. Segmented Strings in $AdS_3$

    CERN Document Server

    Callebaut, Nele; Samberg, Andreas; Toldo, Chiara

    2015-01-01

    We study segmented strings in flat space and in $AdS_3$. In flat space, these well known classical motions describe strings which at any instant of time are piecewise linear. In $AdS_3$, the worldsheet is composed of faces each of which is a region bounded by null geodesics in an $AdS_2$ subspace of $AdS_3$. The time evolution can be described by specifying the null geodesic motion of kinks in the string at which two segments are joined. The outcome of collisions of kinks on the worldsheet can be worked out essentially using considerations of causality. We study several examples of closed segmented strings in $AdS_3$ and find an unexpected quasi-periodic behavior. We also work out a WKB analysis of quantum states of yo-yo strings in $AdS_3$ and find a logarithmic term reminiscent of the logarithmic twist of string states on the leading Regge trajectory.

  7. Polarised black holes in AdS

    Science.gov (United States)

    Costa, Miguel S.; Greenspan, Lauren; Oliveira, Miguel; Penedones, João; Santos, Jorge E.

    2016-06-01

    We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global AdS 4 with conformal boundary {S}2× {{{R}}}t. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic AdS behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an AdS soliton that includes the full backreaction of the electric field on the AdS geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both AdS soliton and black hole phases. The corresponding phase diagram generalizes the Hawking-Page phase transition. The AdS soliton dominates the low temperature phase and the black hole the high temperature phase, with a critical temperature that decreases as the external electric field increases. Finally, we consider the simple case of a free charged scalar field on {S}2× {{{R}}}t with conformal coupling. For a field in the SU(N ) adjoint representation we compare the phase diagram with the above gravitational system.

  8. Adding of ascorbic acid to the culture medium influences the antioxidant status and some biochemical parameters in the hen granulosa cells.

    Science.gov (United States)

    Capcarova, M; Kolesarova, A; Kalafova, A; Bulla, J; Sirotkin, A V

    2015-07-01

    The aim of the present study was to determine the activity of superoxide dismutase (SOD), total antioxidant status (TAS) of the hen granulosa cells, and selected biochemical parameters, including calcium, phosphorus, sodium, potassium, glucose, cholesterol, proteins, in the culture medium of granulosa cells after exposing them to ascorbic acid in vitro conditions. Ovarian granulosa cells of hens were incubated with various doses of ascorbic acid (E1 0.09 mg/ml, E2 0.13 mg/ml, E3 0.17 mg/ml, E4 0.33 mg/ml, E5 0.5 mg/ml). Ascorbic acid did not manifest antioxidant potential and higher doses of ascorbic acid (0.17; 0.33 and 0.5 mg/ml) decreased the activity of SOD in granulosa cells. Vitamin application resulted in a significantly (p<0.05) higher accumulation of Na+ and K+ in culture media of granulosa cells and decreased the concentration of glucose and proteins. These results indicate that ascorbic acid might be involved in the regulation of selected biochemical and physiological processes in ovarian granulosa cells.

  9. Polarised Black Holes in AdS

    CERN Document Server

    Costa, Miguel S.; Oliveira, Miguel; Penedones, João; Santos, Jorge E.

    2016-01-01

    We consider solutions in Einstein-Maxwell theory with a negative cosmological constant that asymptote to global $AdS_{4}$ with conformal boundary $S^{2}\\times\\mathbb{R}_{t}$. At the sphere at infinity we turn on a space-dependent electrostatic potential, which does not destroy the asymptotic $AdS$ behaviour. For simplicity we focus on the case of a dipolar electrostatic potential. We find two new geometries: (i) an $AdS$ soliton that includes the full backreaction of the electric field on the $AdS$ geometry; (ii) a polarised neutral black hole that is deformed by the electric field, accumulating opposite charges in each hemisphere. For both geometries we study boundary data such as the charge density and the stress tensor. For the black hole we also study the horizon charge density and area, and further verify a Smarr formula. Then we consider this system at finite temperature and compute the Gibbs free energy for both $AdS$ soliton and black hole phases. The corresponding phase diagram generalizes the Hawkin...

  10. Constructing Lifshitz solutions from AdS

    CERN Document Server

    Cassani, Davide

    2011-01-01

    Under general assumptions, we show that a gravitational theory in d+1 dimensions admitting an AdS solution can be reduced to a d-dimensional theory containing a Lifshitz solution with dynamical exponent z=2. Working in a d=4, N=2 supergravity setup, we prove that if the AdS background is N=2 supersymmetric, then the Lifshitz geometry preserves 1/4 of the supercharges, and we construct the corresponding Killing spinors. We illustrate these results in examples from supersymmetric consistent truncations of type IIB supergravity, enhancing the class of known 4-dimensional Lifshitz solutions of string theory. As a byproduct, we find a new AdS4 x S1 x T(1,1) solution of type IIB.

  11. Ad Hoc网络%Ad Hoc Network

    Institute of Scientific and Technical Information of China (English)

    王海涛

    2005-01-01

    首先介绍了Ad Hoc网络的基本概念、技术特点以及关键技术等,然后较为全面地归纳了Ad Hoc网络的典型应用,最后讨论了Ad Hoc网络的发展趋势和有待解决的问题.

  12. The effects of adding lactic acid bacteria and cellulase in oil palm (Elais guineensis Jacq.) frond silages on fermentation quality, chemical composition and in vitro digestibility

    NARCIS (Netherlands)

    Ebrahimi, Mahdi; Rajion, Mohamed Ali; Goh, Yong Meng; Farjam, Abdoreza Soleimani; Sazili, Awis Qurni; Schonewille, Jan Thomas

    2014-01-01

    The main objective of the current study was to evaluate whether oil palm frond (OPF) can be successfully ensiled without or with the additives cellulase or lactic acid bacteria (LAB). Thus, fresh OPF was ensiled either without additives or with cellulase or LAB or their combination. Ensiling was

  13. The effects of adding lactic acid bacteria and cellulase in oil palm (Elais guineensis Jacq.) frond silages on fermentation quality, chemical composition and in vitro digestibility

    NARCIS (Netherlands)

    Ebrahimi, Mahdi; Rajion, Mohamed Ali; Goh, Yong Meng; Farjam, Abdoreza Soleimani; Sazili, Awis Qurni; Schonewille, Jan Thomas

    2014-01-01

    The main objective of the current study was to evaluate whether oil palm frond (OPF) can be successfully ensiled without or with the additives cellulase or lactic acid bacteria (LAB). Thus, fresh OPF was ensiled either without additives or with cellulase or LAB or their combination. Ensiling was car

  14. Cost effectiveness of adding nucleic acid testing to hepatitis B, hepatitis C, and human immunodeficiency virus screening of blood donations in Zimbabwe

    NARCIS (Netherlands)

    Mafirakureva, Nyashadzaishe; Mapako, Tonderai; Khoza, Star; Emmanuel, Jean C.; Marowa, Lucy; Mvere, David; Postma, Maarten J.; van Hulst, Marinus

    2016-01-01

    BACKGROUNDThe aim of this study was to assess the cost effectiveness of introducing individual-donation nucleic acid testing (ID-NAT), in addition to serologic tests, compared with the exclusive use of serologic tests for the identification of hepatitis B virus (HBV), hepatitis C virus (HCV), and hu

  15. Effects of linseed and quercetin added to the diet of fattening lambs on the fatty acid profile and lipid antioxidant status of meat samples.

    Science.gov (United States)

    Andrés, S; Morán, L; Aldai, N; Tejido, M L; Prieto, N; Bodas, R; Giráldez, F J

    2014-06-01

    Thirty-two Merino lambs fed barley straw and a concentrate formulated either with palm oil (CTRL group) or with linseed (+LS group), both alone or supplemented with quercetin (+QCT group or +LS+QCT group) were used to assess the effects of these dietary supplements on meat quality attributes. After being slaughtered, the longissimus thoracis muscles were used to study the fatty acid (FA) profile in detail, whilst longissimus lumborum slices were stored under refrigerated conditions to determine the lipid stability. Linseed increased the content of highly unsaturated n-3 long-chain fatty acid (20:5n-3; 22:5n-3; 22:6n-3). Interestingly, a significant increment of rumenic acid content (9c,11t-18:2) was observed when this seed was administered together with dietary quercetin. Moreover, the feeding of quercetin resulted in a reduction in the proportion of saturated FA and a decrease in lipid peroxidation of meat when the lambs were fed linseed. In conclusion, from both a nutritional and a commercial (shelf-life) point of view, it may be useful to include a source of quercetin when lambs are fed linseed diets. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. AdS orbifolds and Penrose limits

    Energy Technology Data Exchange (ETDEWEB)

    Alishahiha, Mohsen; Sheikh-Jabbari, Mohammad M.; Tatar, Radu

    2002-12-09

    In this paper we study the Penrose limit of AdS{sub 5} orbifolds. The orbifold can be either in the pure spatial directions or space and time directions. For the AdS{sub 5}/{Lambda} x S{sup 5} spatial orbifold we observe that after the Penrose limit we obtain the same result as the Penrose limit of AdS{sub 5} x S{sup 5}/{Lambda}. We identify the corresponding BMN operators in terms of operators of the gauge theory on R x S{sup 3}/{Lambda}. The semi-classical description of rotating strings in these backgrounds have also been studied. For the spatial AdS orbifold we show that in the quadratic order the obtained action for the fluctuations is the same as that in S{sup 5} orbifold, however, the higher loop correction can distinguish between two cases.

  17. Effect of γ-amino Butyric Acid and Phytic Acid Content in Germinated Brown Rice by Adding Exogenous Phytase%外源植酸酶对发芽糙米γ一氨基丁酸和植酸含量的影响

    Institute of Scientific and Technical Information of China (English)

    刘玮; 曹龙奎

    2015-01-01

    Effects of adding exogenous phytase on germinated brown rice γ-amino butyric acid and phytic acid content were studied.γ-amino butyric acid content in germinated brown rice could be increase, and levels of phytase could be reduce by adding exogenous phytase, thus nutritional value of brown rice germination could be improve.%本文研究了添加外源植酸酶对发芽糙米γ一氨基丁酸和植酸含量的影响,通过添加外源植酸酶,可以增加发芽糙米γ一氨基丁酸含量,降低植酸酶含量,从而提高发芽糙米的营养价值。

  18. Superradiant instability in AdS

    CERN Document Server

    Ganchev, Bogdan

    2016-01-01

    The phenomenon of superradiance in the context of asymptotically global AdS spacetimes is investigated with particular accent on its effect on the stability of the systems under consideration. To this end, the concept of an asymptotically AdS spacetime is explained, together with its implications on the boundary conditions at $\\mathcal{I}$, as well as the Newman-Penrose-Teukolsky formalism, whereby the Teukolsky master equation in a most general form for Kerr-AdS is given. Furthermore, work done in the cases of RN-AdS and Kerr-AdS is laid out in a concise manner, putting emphasis on the important steps taken in determining the endpoint of the superradiant instability in the two configurations. For the former this turns out to be a black hole with reduced charge and a static charged scalar condensate around it, whereas for the latter two of the more probable outcomes are presented, both of which imply a violation of one of the cosmic censorships.

  19. Lorentzian AdS, Wormholes and Holography

    CERN Document Server

    Arias, Raul E; Silva, Guillermo A

    2011-01-01

    We investigate the structure of two point functions for the QFT dual to an asymptotically Lorentzian AdS-wormhole. The bulk geometry is a solution of 5-dimensional second order Einstein Gauss Bonnet gravity and causally connects two asymptotically AdS space times. We revisit the GKPW prescription for computing two-point correlation functions for dual QFT operators O in Lorentzian signature and we propose to express the bulk fields in terms of the independent boundary values phi_0^\\pm at each of the two asymptotic AdS regions, along the way we exhibit how the ambiguity of normalizable modes in the bulk, related to initial and final states, show up in the computations. The independent boundary values are interpreted as sources for dual operators O^\\pm and we argue that, apart from the possibility of entanglement, there exists a coupling between the degrees of freedom leaving at each boundary. The AdS_(1+1) geometry is also discussed in view of its similar boundary structure. Based on the analysis, we propose a ...

  20. The effects of adding lactic acid bacteria and cellulase in oil palm (Elais guineensis Jacq. frond silages on fermentation quality, chemical composition and in vitro digestibility

    Directory of Open Access Journals (Sweden)

    Mahdi Ebrahimi

    2014-07-01

    Full Text Available The main objective of the current study was to evaluate whether oil palm frond (OPF can be successfully ensiled without or with the additives cellulase or lactic acid bacteria (LAB. Thus, fresh OPF was ensiled either without additives or with cellulase or LAB or their combination. Ensiling was carried out by storing 2 kg samples in airtight glass jars at 25- 30°C for 12 weeks. Thereafter, the silage samples were subjected to proximate analyses, an in vitro digestibility assay and measures on selected indices of fermentation. Fermentation of OPF without additives appeared to be unsuccessful as both pH and ammonia content were too high (4.9 and 9.9%, respectively. In contrast, the use of cellulase or LAB resulted in silages with a pH<4.5 and ammonia fractions <8.4%, but the lowest values were found when both cellulase and LAB were used, i.e. pH=4.1 and ammonia fraction=6.7%. In vitro digestibility of dry matter was significantly higher in the cellulase treated silages. The process of ensiling was associated with both a significant decrease of the fat content of OPF and a significant change of the fatty acid profile. However, the proportions of major fatty acids (C16:0 and C18:2n-6 were not affected by the process of ensiling. In conclusion, the use of cellulase additive appears a practical tool to safeguard the process of fermentation. Using a cellulase enzyme or its combination with LAB improves the fermentation profile and increases the nutritional value of the OPF silage.

  1. Effect of adding amino acids residues in N- and C-terminus of Vip3Aa16 (L121I) toxin.

    Science.gov (United States)

    Sellami, Sameh; Cherif, Marwa; Jamoussi, Kaïs

    2016-06-01

    To study the importance of N- and C-terminus of Bacillus thuringiensis Vip3Aa16 (L121I) toxin (88 kDa), a number of mutants were generated. The addition of two (2R: RS) or eleven (11R: RSRPGHHHHHH) amino acid residues at the Vip3Aa16 (L121I) C-terminus allowed to an unappropriated folding illustrated by the abundant presence of the 62 kDa proteolytic form. The produced Vip3Aa16 (L121I) full length form was less detected when increasing the number of amino acids residues in the C-terminus. Bioassays demonstrated that the growth of the lepidopteran Ephestia kuehniella was slightly affected by Vip3Aa16 (L121I)-2R and not affected by Vip3Aa16 (L121I)-11R. Additionally, the fusion at the Vip3Aa16 (L121I) N-terminus of 39 amino acids harboring the E. coli OmpA leader peptide and the His-tag sequence allowed to the increase of protease sensitivity of Vip3Aa16 (L121I) full length form, as only the 62 kDa proteolysis form was detected. Remarkably, this fused protein produced in Escherichia coli (E. coli) was biologically inactive toward Ephestia kuehniella larvae. Thus, the N-terminus of the protein is required to the accomplishment of the insecticidal activity of Vip3 proteins. This report serves as guideline for the study of Vip3Aa16 (L121I) protein stability and activity.

  2. Performance of electrolyte for PVA added colloid lead-acid battery%含添加剂PVA的胶体铅酸电池电解质性能

    Institute of Scientific and Technical Information of China (English)

    马运法; 林本慧

    2014-01-01

    To improve the physical properties and electrochemical performance of gel electrolyte, gel electrolytes with different contents of polyving alcohol(PVA)were prepared. Test results of viscosity,strength and gelling time tests showed that viscosity was increased with increasing PVA content and increased significantly when the content was over 0.0050%. Gel strength was enhanced and gelling time was prolonged when adding PVA of 0.0025%and 0.0050%,and gel performance was improved. However,physical properties of the electrolyte could not be improved,when the content of PVA was further increased. Cyclic voltammetry and AC impedance spectroscopy test results showed that adding PVA of 0.0050% could improve the reaction current and power of electrode,increase the utilization of active material and oxygen evolution potential,suppress self-discharge and lower impedance of electrolyte , electrochemical reaction charge transfer resistance and capacitance.%为改善胶体电解质的物理性质,提高电化学性能,制备了不同聚乙烯醇(PVA)含量的胶体电解质,黏度、强度和胶凝时间测试结果表明,黏度随PVA含量的提高而增加,在含量0.0050%之后增加显著;加入0.0025%和0.0050% PVA,凝胶强度增大,胶凝时间延长,凝胶性能得到改善,但继续提高PVA含量对改善电解质的物理性质不利。循环伏安和交流阻抗测试结果表明,加入0.0050% PVA可提高电极的反应电流和电量,有利于提高活性物质的利用率、析氧过电位,抑制自放电,降低电解质的阻抗、电化学反应的电荷转移电阻和电容。

  3. Ice core profiles of saturated fatty acids (C12:0-C30:0) and oleic acid (C18:1) from southern Alaska since 1734 AD: A link to climate change in the Northern Hemisphere

    Science.gov (United States)

    Pokhrel, Ambarish; Kawamura, Kimitaka; Seki, Osamu; Matoba, Sumio; Shiraiwa, Takayuki

    2015-01-01

    An ice core drilled at Aurora Peak in southeast Alaska was analyzed for homologous series of straight chain fatty acids (C12:0-C30:0) including unsaturated fatty acid (oleic acid) using gas chromatography (GC/FID) and GC/mass spectrometry (GC/MS). Molecular distributions of fatty acids are characterized by even carbon number predominance with a peak at palmitic acid (C16:0, av. 20.3 ± SD. 29.8 ng/g-ice) followed by oleic acid (C18:1, 19.6 ± 38.6 ng/g-ice) and myristic acid (C14:0, 15.3 ± 21.9 ng/g-ice). The historical trends of short-chain fatty acids, together with correlation analysis with inorganic ions and organic tracers suggest that short-chain fatty acids (except for C12:0 and C15:0) were mainly derived from sea surface micro layers through bubble bursting mechanism and transported over the glacier through the atmosphere. This atmospheric transport process is suggested to be linked with Kamchatka ice core δD record from Northeast Asia and Greenland Temperature Anomaly (GTA). In contrast, long-chain fatty acids (C20:0-C30:0) are originated from terrestrial higher plants, soil organic matter and dusts, which are also linked with GTA. Hence, this study suggests that Alaskan fatty acids are strongly influenced by Pacific Decadal Oscillation/North Pacific Gyre Oscillation and/or extra tropical North Pacific surface climate and Arctic oscillation. We also found that decadal scale variability of C18:1/C18:0 ratios in the Aurora Peak ice core correlate with the Kamchatka ice core δD, which reflects climate oscillations in the North Pacific. This study suggests that photochemical aging of organic aerosols could be controlled by climate periodicity.

  4. Boson Stars in AdS

    CERN Document Server

    Buchel, Alex; Lehner, Luis

    2013-01-01

    We construct boson stars in global Anti de Sitter (AdS) space and study their stability. Linear perturbation results suggest that the ground state along with the first three excited state boson stars are stable. We evolve some of these solutions and study their nonlinear stability in light of recent work \\cite{Bizon:2011gg} arguing that a weakly turbulent instability drives scalar perturbations of AdS to black hole formation. However evolutions suggest that boson stars are nonlinearly stable and immune to the instability for sufficiently small perturbation. Furthermore, these studies find other families of initial data which similarly avoid the instability for sufficiently weak parameters. Heuristically, we argue that initial data families with widely distributed mass-energy distort the spacetime sufficiently to oppose the coherent amplification favored by the instability. From the dual CFT perspective our findings suggest that there exist families of rather generic initial conditions in strongly coupled CFT ...

  5. AdS solutions through transgression

    Energy Technology Data Exchange (ETDEWEB)

    Donos, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Gauntlett, J.P. [Imperial College, London (United Kingdom). Blackett Lab.]|[Imperial College, London (United Kingdom). The Institute for Mathematical Sciences; Kim, Nakwoo [Kyung Hee Univ., Seoul (Korea). Dept. of Physics and Research Inst. of Basic Science

    2008-07-15

    We present new classes of explicit supersymmetric AdS{sub 3} solutions of type IIB supergravity with non-vanishing five-form flux and AdS{sub 2} solutions of D=11 supergravity with electric four-form flux. The former are dual to two-dimensional SCFTs with (0,2) supersymmetry and the latter to supersymmetric quantum mechanics with two supercharges. We also investigate more general classes of AdS{sub 3} solutions of type IIB supergravity and AdS{sub 2} solutions of D=11 supergravity which in addition have non-vanishing three-form flux and magnetic four-form flux, respectively. The construction of these more general solutions makes essential use of the Chern-Simons or ''transgression'' terms in the Bianchi identity or the equation of motion of the field strengths in the supergravity theories. We construct infinite new classes of explicit examples and for some of the type IIB solutions determine the central charge of the dual SCFTs. The type IIB solutions with non-vanishing three-form flux that we construct include a two-torus, and after two T-dualities and an S-duality, we obtain new AdS3 solutions with only the NS fields being non-trivial. (orig.)

  6. Refined Holographic Entanglement Entropy for the AdS Solitons and AdS black Holes

    CERN Document Server

    Ishihara, Masafumi; Ning, Bo

    2012-01-01

    We consider the refinement of the holographic entanglement entropy on a disk region for the holographic dual theories to the AdS solitons and AdS black holes, including the corrected ones by the Gauss-Bonnet term. The AdS soliton is dual to a gapped system with an IR fixed-point. The refinement is obtained by extracting the UV-independent piece of the holographic entanglement entropy. We then study the renormalization group (RG) flow of the refinement by tuning the linear size of the chosen disk region. Our main results are (i) the RG flow of the refinement decreases monotonically for most of the cases; (ii) there is no topological entanglement entropy for AdS$_5$ soliton even with Gauss-Bonnet correction; (iii) for the AdS black holes, the refinement obeys the volume law at IR regime, and the transition between UV and IR regimes is a smooth crossover; however, the crossover will turn into phase transition by the Gauss-Bonnet correction; (iv) for the AdS solitons, there are discontinuous phase transitions bet...

  7. Predicting AD conversion

    DEFF Research Database (Denmark)

    Liu, Yawu; Mattila, Jussi; Ruiz, Miguel �ngel Mu�oz

    2013-01-01

    To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool) and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA) on MRI...

  8. An AdS Crunch in Supergravity

    Science.gov (United States)

    Hertog, Thomas

    2004-12-01

    We review some properties of N=8 gauged supergravity in four dimensions with modified, but AdS invariant boundary conditions on the m2 = -2 scalars. There is a one-parameter class of asymptotic conditions on these fields and the metric components, for which the full AdS symmetry group is preserved. The generators of the asymptotic symmetries are finite, but acquire a contribution from the scalar fields. For a large class of such boundary conditions, we find there exist black holes with scalar hair that are specified by a single conserved charge. Since Schwarschild-AdS is a solution too for all boundary conditions, this provides an example of black hole non-uniqueness. We also show there exist solutions where smooth initial data evolve to a big crunch singularity. This opens up the possibility of using the dual conformal field theory to obtain a fully quantum description of the cosmological singularity, and we report on a preliminary study of this.

  9. Adding more value to added-value

    DEFF Research Database (Denmark)

    Marian, Livia

    regulation. The results of a qualitative concept test reveal positive attitudes towards the proposed production process. The discussions about fewer standards being sufficient or about options “in-between” conventional and organic standards indicate that the difference in production processes is noticed, yet...... it is probably valued less than expected. The added attributes need to be thoroughly considered when developing and marketing “organic plus” products, as their effect on other product characteristics (e.g. high prices) can detract from their added value....

  10. 小麦粉中添加植酸对馒头品质的影响%Effects of Added Phytic Acid in Wheat Flour on Quality of Chinese Steamed Bread

    Institute of Scientific and Technical Information of China (English)

    吴澎; 陈建省; 段纯明; 田纪春

    2011-01-01

    As a new natural food additive, phytic acid is used as antioxidant, antiseptic, ferment accelerant and chelant in food industry. In the experiment, three kinds of wheat flour with three different gluten gradients were used and added with the phytic acid with the proportion of 0.005% ,0.025% ,0.05% ,0.1% ,0. 15% and 0.2% (phytic acid:wheat flour), and then were used to make Chinese steamed bread, so as to measure its structural features and evaluate the steamed bread. The result indicated that with the increase in the proportion of phytic acid, the textural properties of steamed breads had a little changes, while the volume and the total score of steamed breads reduced slightly, but the color of steamed breads improved slightly. Significant negative correlations were detected between hardness, cohesiveness, adhesiveness, chewiness, volume with the increase proportion of phytic acid, while no significant correlations were identified between other properties with the increase in the proportion of phytic acid. In conclusion,there was no significant influence of the addition of phytic acid on the quality of steamed bread.%植酸是一种新型的天然食品添加剂,作为抗氧化剂、防腐剂、发酵促进剂或螯合剂广泛用于食品工业.试验利用3个不同筋力梯度的小麦粉,按0.005%、0.025%、0.05%、0.1%、0.15%、0.20%(植酸与制造馒头小麦粉质量比)的比例添加植酸后制作馒头,测定其质构特性并做馒头感官评价试验.结果表明,随着植酸添加比例的增加,馒头的体积和评分值均有小幅度下降,但是无论馒头瓤和皮的色差都有小幅度的增白现象.硬度、黏着性、胶着性、咀嚼性和体积与植酸添加量呈显著线性负相关,其余性状与植酸添加量的相关性不显著.但总的来说,添加植酸对馒头的品质特性没有起到显著性的影响.

  11. Probing crunching AdS cosmologies

    Science.gov (United States)

    Kumar, S. Prem; Vaganov, Vladislav

    2016-02-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of {N}=8 supergravity on AdS4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã max. Radial geodesics connecting antipodal points necessarily have de Sitter energy Ɛ ≲ ã max, while geodesics with Ɛ > ã max terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outward" in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green's function has a branch point determined by ã max which corresponds to the lowest quasinormal frequency.

  12. The political attack ad

    Directory of Open Access Journals (Sweden)

    Palma Peña-Jiménez, Ph.D.

    2011-01-01

    Full Text Available During election campaigns the political spot has a clear objective: to win votes. This message is communicated to the electorate through television and Internet, and usually presents a negative approach, which includes a direct critical message against the opponent, rather than an exposition of proposals. This article is focused on the analysis of the campaign attack video ad purposely created to encourage the disapproval of the political opponent among voters. These ads focus on discrediting the opponent, many times, through the transmission of ad hominem messages, instead of disseminating the potential of the political party and the virtues and manifesto of its candidate. The article reviews the development of the attack ad since its first appearance, which in Spain dates back to 1996, when the famous Doberman ad was broadcast, and examines the most memorable campaign attack ads.

  13. Engineering E. coli for the biosynthesis of 3-hydroxy-γ-butyrolactone (3HBL) and 3,4-dihydroxybutyric acid (3,4-DHBA) as value-added chemicals from glucose as a sole carbon source.

    Science.gov (United States)

    Dhamankar, Himanshu; Tarasova, Yekaterina; Martin, Collin H; Prather, Kristala L J

    2014-09-01

    3-hydroxy-γ-butyrolactone (3HBL) is a versatile chiral synthon, deemed a top value-added chemical from biomass by the DOE. We recently reported the first biosynthetic pathway towards 3HBL and its hydrolyzed form, 3,4-dihydroxybutyric acid (3,4-DHBA) in recombinant Escherichia coli using glucose and glycolic acid as feedstocks and briefly described their synthesis solely from glucose. Synthesis from glucose requires integration of the endogenous glyoxylate shunt with the 3,4-DHBA/3HBL pathway and co-overexpression of seven genes, posing challenges with respect to expression, repression of the glyoxylate shunt and optimal carbon distribution between the two pathways. Here we discuss engineering this integration. While appropriate media and over-expression of glyoxylate shunt enzymes helped overcome repression, two orthogonal expression systems were employed to address the expression and carbon distribution challenge. Synthesis of up to 0.3g/L of 3HBL and 0.7g/L of 3,4-DHBA solely from glucose was demonstrated, amounting to 24% of the theoretical maximum.

  14. Probing crunching AdS cosmologies

    CERN Document Server

    Kumar, S Prem

    2015-01-01

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS_4, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor a_{max} . Radial geodesics connecting antipodal points necessarily have de Sitter energy E \\leq a_{max}, while geodesics with E > a_{max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved "outw...

  15. Holography of AdS vacuum bubbles

    Energy Technology Data Exchange (ETDEWEB)

    Barbon, J.L.F. [Instituto de Fisica Teorica IFT UAM/CSIC, Cantoblanco, Madrid 28049 (Spain); Rabinovici, E. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)

    2011-07-15

    We consider the fate of AdS vacua connected by tunneling events. A precise holographic dual of thin-walled Coleman-de Luccia bounces is proposed in terms of Fubini instantons in an unstable CFT. This proposal is backed by several qualitative and quantitative checks, including the precise calculation of the instanton action appearing in evaluating the decay rate. Big crunches manifest themselves as time dependent processes which reach the boundary of field space in a finite time. The infinite energy difference involved is identified on the boundary and highlights the ill-defined nature of the bulk setup. We propose a qualitative scenario in which the crunch is resolved by stabilizing the CFT, so that all attempts at crunching always end up shielded from the boundary by the formation of black hole horizons. In all these well defined bulk processes the configurations have the same asymptotics and are finite energy excitations.

  16. Twistor methods for AdS$_5$

    CERN Document Server

    Adamo, Tim; Williams, Jack

    2016-01-01

    We consider the application of twistor theory to five-dimensional anti-de Sitter space. The twistor space of AdS$_5$ is the same as the ambitwistor space of the four-dimensional conformal boundary; the geometry of this correspondence is reviewed for both the bulk and boundary. A Penrose transform allows us to describe free bulk fields, with or without mass, in terms of data on twistor space. Explicit representatives for the bulk-to-boundary propagators of scalars and spinors are constructed, along with twistor action functionals for the free theories. Evaluating these twistor actions on bulk-to-boundary propagators is shown to produce the correct two-point functions.

  17. AdS2 holographic dictionary

    Science.gov (United States)

    Cvetič, Mirjam; Papadimitriou, Ioannis

    2016-12-01

    We construct the holographic dictionary for both running and constant dilaton solutions of the two dimensional Einstein-Maxwell-Dilaton theory that is obtained by a circle reduction from Einstein-Hilbert gravity with negative cosmological constant in three dimensions. This specific model ensures that the dual theory has a well defined ultraviolet completion in terms of a two dimensional conformal field theory, but our results apply qualitatively to a wider class of two dimensional dilaton gravity theories. For each type of solutions we perform holographic renormalization, compute the exact renormalized one-point functions in the presence of arbitrary sources, and derive the asymptotic symmetries and the corresponding conserved charges. In both cases we find that the scalar operator dual to the dilaton plays a crucial role in the description of the dynamics. Its source gives rise to a matter conformal anomaly for the running dilaton solutions, while its expectation value is the only non trivial observable for constant dilaton solutions. The role of this operator has been largely overlooked in the literature. We further show that the only non trivial conserved charges for running dilaton solutions are the mass and the electric charge, while for constant dilaton solutions only the electric charge is non zero. However, by uplifting the solutions to three dimensions we show that constant dilaton solutions can support non trivial extended symmetry algebras, including the one found by Compère, Song and Strominger [1], in agreement with the results of Castro and Song [2]. Finally, we demonstrate that any solution of this specific dilaton gravity model can be uplifted to a family of asymptotically AdS2 × S 2 or conformally AdS2 × S 2 solutions of the STU model in four dimensions, including non extremal black holes. The four dimensional solutions obtained by uplifting the running dilaton solutions coincide with the so called `subtracted geometries', while those obtained

  18. Skil problemerne ad

    DEFF Research Database (Denmark)

    Kaspersen, Peter

    2007-01-01

    På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger.......På grundlag af evalueringer og forskning i gymnasiereformen 2005 foreslås det at skille problemerne ad i forskellige niveauer. Herved kan der arbejdes med niveaudelte løsninger....

  19. Probing crunching AdS cosmologies

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, S. Prem; Vaganov, Vladislav [Department of Physics, Swansea University,Singleton Park, Swansea SA2 8PP (United Kingdom)

    2016-02-03

    Holographic gravity duals of deformations of CFTs formulated on de Sitter spacetime contain FRW geometries behind a horizon, with cosmological big crunch singularities. Using a specific analytically tractable solution within a particular single scalar truncation of N=8 supergravity on AdS{sub 4}, we first probe such crunching cosmologies with spacelike radial geodesics that compute spatially antipodal correlators of large dimension boundary operators. At late times, the geodesics lie on the FRW slice of maximal expansion behind the horizon. The late time two-point functions factorise, and when transformed to the Einstein static universe, they exhibit a temporal non-analyticity determined by the maximal value of the scale factor ã{sub max}. Radial geodesics connecting antipodal points necessarily have de Sitter energy E≲ã{sub max}, while geodesics with E>ã{sub max} terminate at the crunch, the two categories of geodesics being separated by the maximal expansion slice. The spacelike crunch singularity is curved “outward” in the Penrose diagram for the deformed AdS backgrounds, and thus geodesic limits of the antipodal correlators do not directly probe the crunch. Beyond the geodesic limit, we point out that the scalar wave equation, analytically continued into the FRW patch, has a potential which is singular at the crunch along with complex WKB turning points in the vicinity of the FRW crunch. We then argue that the frequency space Green’s function has a branch point determined by ã{sub max} which corresponds to the lowest quasinormal frequency.

  20. Mobile ad hoc networking

    CERN Document Server

    John Wiley & Sons

    2004-01-01

    "Assimilating the most up-to-date information on research and development activities in this rapidly growing area, Mobile Ad Hoc Networking covers physical, data link, network, and transport layers, as well as application, security, simulation, and power management issues in sensor, local area, personal, and mobile ad hoc networks. Each of the book's sixteen chapters has been written by a top expert and discusses in-depth the most important topics in the field. Mobile Ad Hoc Networking is an excellent reference and guide for professionals seeking an in-depth examination of topics that also provides a comprehensive overview of the current state-of-the-art."--Jacket.

  1. Effects of fish oil and starch added to a diet containing sunflower-seed oil on dairy goat performance, milk fatty acid composition and in vivo delta9-desaturation of [13C]vaccenic acid.

    Science.gov (United States)

    Bernard, Laurence; Mouriot, Julien; Rouel, Jacques; Glasser, Frédéric; Capitan, Pierre; Pujos-Guillot, Estelle; Chardigny, Jean-Michel; Chilliard, Yves

    2010-08-01

    The potential benefits on human health have prompted an interest in developing nutritional strategies for specifically increasing rumenic acid (RA) in ruminant milk. The aims of the present study were to (i) compare two dietary treatments with lipid supplements on milk yield and composition, (ii) measure the in vivo delta9-desaturation of vaccenic acid (VA) to RA using 13C-labelled VA and (iii) determine the effect of the dietary treatments on this variable. Treatments were 90 g sunflower-seed oil (SO) per d or 60 g sunflower-seed oil and 30 g fish oil per d plus additional starch (SFO), in a grassland hay-based diet given to eight Alpine goats in a 2 x 2 cross-over design with 21 d experimental periods. Milk yield and composition were similar between treatments. Goats fed SFO had higher milk 6 : 0-16 : 0 concentration, lower milk sigmaC18 concentrations and showed no effect on milk VA and RA, compared with SO. At the end of the experiment, intravenous injection of 1.5 g [13C]VA followed by measurements of milk lipid 13C enrichment showed that in vivo 31.7 and 31.6 % of VA was delta9-desaturated into milk RA in the caprine with the SO and SFO treatments, respectively. The expression of genes encoding for delta9-desaturase (or stearoyl-CoA desaturase; SCD1, SCD5) in mammary tissues and four milk delta9-desaturation ratios were similar between treatments. In conclusion, the present study provides the first estimates of in vivo endogenous synthesis of RA (63-73 % of milk RA) from VA in goats, and shows no difference between the two lipid supplements compared.

  2. Antiproton-Decelerator (AD)

    CERN Multimedia

    Laurent Guiraud

    1998-01-01

    When the Low-Energy Antiproton Ring (LEAR) was stopped in 1996, because of its costly operation, a cheaper way of continuing low-energy antiproton physics was sought. The Antiproton-Collector (AC), added in 1987 to the Antiproton Accumulator (AA) to provide a tenfold intensity increase, was converted into the Antiproton-Decelerator (AD). Antiprotons from the target at 3.5 GeV/c are decelerated to 100 MeV/c, and fast-ejected to the experiments. Major changes were necessary. Above all, the conversion from a constant-field machine to one with a magnetic cycle, modulating the field by an impressive factor 35. New systems for stochastic and electron cooling had to be added. Beam diagnostics at an intensity of only 2E7 antiprotons was a challenge. In 2000, the AD began delivery of antiprotons to the experiments.

  3. Value Adding Management

    DEFF Research Database (Denmark)

    Jensen, Per Anker; Katchamart, Akarapong

    2011-01-01

    Purpose: To investigate how Facilities Management (FM) can add value and develop a management concept that can assist facilities managers in implementing value adding strategies and practices. Theory: The study is based on the management model for FM included in the European FM standards, recent...... theories on added value of FM and real estate and the related concept of Value Management from building projects. The study is related to the EuroFM research group on The Added Value of FM. Design/methodology/approach: The study outlines a preliminary theoretical based management concept, which...... is investigated, tested and discussed based on a case study of an international corporation. Findings: The study shows that the management model for FM creates a relevant starting point but also that stakeholder and relationship management is an essential aspect of Value Adding Management. The case study confirms...

  4. AdS_3: the NHEK generation

    CERN Document Server

    Bena, Iosif; Puhm, Andrea

    2015-01-01

    It was argued in arXiv:1203.4227 that the five-dimensional near-horizon extremal Kerr (NHEK) geometry can be embedded in String Theory as the infrared region of an infinite family of non-supersymmetric geometries that have D1, D5, momentum and KK monopole charges. We show that there exists a method to embed these geometries into asymptotically-AdS_3 x S^3/Z_N solutions, and hence to obtain infinite families of flows whose infrared is NHEK. This indicates that the CFT dual to the NHEK geometry is the IR fixed point of a Renormalization Group flow from a known local UV CFT and opens the door to its explicit construction.

  5. Iron bioavailability from a lipid-based complementary food fortificant mixed with millet porridge can be optimized by adding phytase and ascorbic acid but not by using a mixture of ferrous sulfate and sodium iron EDTA.

    Science.gov (United States)

    Cercamondi, Colin I; Egli, Ines M; Mitchikpe, Evariste; Tossou, Felicien; Hessou, Joamel; Zeder, Christophe; Hounhouigan, Joseph D; Hurrell, Richard F

    2013-08-01

    Home fortification with lipid-based nutrient supplements (LNSs) is a promising approach to improve bioavailable iron and energy intake of young children in developing countries. To optimize iron bioavailability from an LNS named complementary food fortificant (CFF), 3 stable isotope studies were conducted in 52 young Beninese children. Test meals consisted of millet porridge mixed with CFF and ascorbic acid (AA). Study 1 compared iron absorption from FeSO4-fortifed meals with meals fortified with a mixture of FeSO4 and NaFeEDTA. Study 2 compared iron absorption from FeSO4-fortifed meals without or with extra AA. Study 3 compared iron absorption from FeSO4-fortified meals with meals containing phytase added prior to consumption, once without or once with extra AA. Iron absorption was measured as erythrocyte incorporation of stable isotopes. In study 1, iron absorption from FeSO4 (8.4%) was higher than that from the mixture of NaFeEDTA and FeSO4 (5.9%; P porridge.

  6. 添加乳酸菌和菠萝皮对柱花草青贮品质的影响%Effects of adding lactic acid bacteria and pineapple peel on Stylosanthes silage quality

    Institute of Scientific and Technical Information of China (English)

    申成利; 陈明霞; 李国栋; 张建国

    2012-01-01

    柱花草是热带、亚热带的优质豆科牧草,蛋白含量高、营养品质好,为促进柱花草的加工利用,本试验研究了添加不同乳酸菌和菠萝皮对其青贮发酵品质和有氧稳定性的影响.青贮处理为CK(对照)、LQ(青贮宝)、LF(发酵乳杆菌)、LP(植物乳杆菌)、LS(鼠李糖乳杆菌)、B(20%菠萝皮)、BLQ(B+ LQ)、BLF(B+LF)、BLP(B+LP)、BLS(B+LS).添加处理后青贮60 d进行分析.结果表明,柱花草含有较少的可溶性碳水化合物和乳酸菌,自然青贮其pH超过5.0,发酵品质差;所有添加物都显著降低pH、增加乳酸含量(P<0.05),明显改善了柱花草青贮料的发酵品质.单独添加菠萝皮的丁酸和NH3-N含量显著高于所有单独添加乳酸菌(P<0.05),pH与LP以外的其他3种乳酸菌差异不显著(P>0.05).除LP的乙酸含量较高,丁酸含量较低外,4种乳酸菌对其他各个发酵指标的影响没有显著差异(P>0.05).本试验所用4种乳酸菌与菠萝皮混合添加,都进一步改善了柱花草青贮料的发酵品质,特别是BLP的青贮效果最佳,其pH值、乙酸和NH3-N含量低,乳酸含量及乳酸与乙酸比高.青贮袋开封后,包括对照在内的所有青贮料的有氧稳定性均较佳.%Stylosanthes is a legume forage which has high protein content and good nutritional quality in tropical and subtropical areas. To promote the utilization of Stylosanthes, the effects of adding lactic acid bacteria and pineapple peel on the silage fermentation quality and aerobic stability were studied after 60 days storage. The experimental treatments were CK (no additive), LQ (commercial inoculant) , LF (Lactobacillus fermentum) , LP (L. plantarum), LS (L. rhamnosus) , B (20% pineapple peel) , BLQ (B+LQ), BLF (B+LF) , BLP (B+ LP) , and BLS (B+LS). Stylosanthes silage had few water soluble carbohydrates and lactic acid bacteria, together with poor quality and a high pH (>5. 0) when there were no additives. All the additives

  7. Dynamic ad hoc networks

    CERN Document Server

    Rashvand, Habib

    2013-01-01

    Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s

  8. D-branes in Lorentzian AdS(3)

    CERN Document Server

    Israel, D

    2005-01-01

    We study the exact construction of D-branes in Lorentzian AdS(3). We start by defining a family of conformal field theories that gives a natural Euclidean version of the SL(2,R) CFT and does not correspond to H(3)+, the analytic continuation of AdS(3). We argue that one can recuperate the exact CFT results of Lorentzian AdS(3), upon an analytic continuation in the moduli space of these conformal field theories. Then we construct exact boundary states for various symmetric and symmetry-breaking D-branes in AdS(3).

  9. Localization on $AdS_2\\times S^1$

    CERN Document Server

    David, Justin R; Gupta, Rajesh Kumar; Narain, Kumar

    2016-01-01

    Conformal symmetry relates the metric on $AdS_2 \\times S^{1}$ to that of $S^3$. This implies that under a suitable choice of boundary conditions for fields on $AdS_2$ the partition function of conformal field theories on these spaces must agree which makes $AdS_2 \\times S^{1}$ a good testing ground to study localization on non-compact spaces. We study supersymmetry on $AdS_2\\times S^1$ and determine the localizing Lagrangian for ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2\\times S^1$. We evaluate the partition function of ${\\cal N}=2$ supersymmetric Chern-Simons theory on $AdS_2 \\times S^1$ using localization, where the radius of $S^1$ is $q$ times that of $AdS_2$. With boundary conditions on $AdS_2\\times S^1$ which ensure that all the physical fields are normalizable and lie in the space of square integrable wave functions in $AdS_2$, the result for the partition function precisely agrees with that of the theory on the $q$-fold covering of $S^3$.

  10. Microbial production of value-added nutraceuticals.

    Science.gov (United States)

    Wang, Jian; Guleria, Sanjay; Koffas, Mattheos A G; Yan, Yajun

    2016-02-01

    Nutraceuticals are important natural bioactive compounds that confer health-promoting and medical benefits to humans. Globally growing demands for value-added nutraceuticals for prevention and treatment of human diseases have rendered nutraceuticals a multi-billion dollar market. However, supply limitations and extraction difficulties from natural sources such as plants, animals or fungi, restrict the large-scale use of nutraceuticals. Metabolic engineering via microbial production platforms has been advanced as an eco-friendly alternative approach for production of value-added nutraceuticals from simple carbon sources. Microbial platforms like the most widely used Escherichia coli and Saccharomyces cerevisiae have been engineered as versatile cell factories for production of diverse and complex value-added chemicals such as phytochemicals, prebiotics, polysaccaharides and poly amino acids. This review highlights the recent progresses in biological production of value-added nutraceuticals via metabolic engineering approaches.

  11. Ads in Indonesia

    Directory of Open Access Journals (Sweden)

    Wulan Roro Retno

    2017-01-01

    Full Text Available Cosmetics industry created the beauty myth for women through advertising. A cosmetic ad in Indonesia has spread a new concept of white skin: East Asia beauty myth. The white concept of Asia white skin basically derived from colonial legacy. The purpose of the research was analyzing the beauty myth in Indonesia ads using postcolonial perspective. The principal result brought the discourse analysis and postcolonial perspective a new insight in communication research. Particularly on media and cultural studies. Major conclusions showed that the beauty myth since the Dutch colonial period never been change. The main concept is always in colonialism’s idea: “white is better”. The West is better than the East.

  12. Adding linear orders

    CERN Document Server

    Shelah, Saharon

    2011-01-01

    We address the following question: Can we expand an NIP theory by adding a linear order such that the expansion is still NIP? Easily, if acl(A)=A for all A, then this is true. Otherwise, we give counterexamples. More precisely, there is a totally categorical theory for which every expansion by a linear order has IP. There is also an \\omega-stable NDOP theory for which every expansion by a linear order interprets bounded arithmetic.

  13. AdS 3-manifolds and Higgs bundles

    DEFF Research Database (Denmark)

    Alessandrini, Daniele; Li, Qiongling

    2015-01-01

    In this paper we investigate the relationships between closed AdS 3-manifolds and Higgs bundles. We have a new way to construct AdS structures that allows us to see many of their properties explicitly, for example we can recover the very recent formula by Tholozan for the volumes. We also find...

  14. Pathologies in Lovelock AdS Black Branes and AdS/CFT

    CERN Document Server

    Takahashi, Tomohiro

    2011-01-01

    We study the pathologies in AdS black branes in Lovelock theory. More precisely, we examine the conditions that AdS black branes have the naked singularity, the ghost instability and the dynamical instability. From the point of view of the AdS/CFT correspondence, the pathologies in AdS black branes indicate the pathologies in the corresponding CFT. Hence, we need to be careful when we apply AdS/CFT in Lovelock theory to various phenomena such as the shear viscosity to entropy ratio in strongly coupled quantum filed theory.

  15. The effect of Ad

    Institute of Scientific and Technical Information of China (English)

    李小艳

    2010-01-01

    There is the trend that now people appreciate those who are slim and regard slim even thin people beautiful. The thinner a person is, the more beautiful. Women, born to pursuit beauty, try various means to follow the trend. We all watch TV, and find a lot of advertisements on diet. The effect of them is tremendous. We all know the fact that it is not at all the better mouse trap will catch mouse. The sales methods are more important. If an advertisement is very interesting and seemingly effective, people will be lured by the ad and then try some of the products.

  16. Management job ads

    DEFF Research Database (Denmark)

    2014-01-01

    The article asks whether it is not the responsibility of corporations to address the issue of women being underrepresented in Danish management jobs. In other words, it is argued that corporations should be encouraged to engage more actively in the recruitment of both men and women for management...... that this agreement reflects a high degree of conservatism in the system where men enjoy a considerable advantage and where procedures that ensure male dominance are perpetuated even in the linguistic and discursive construction of job ads....

  17. Eating ad Libitum

    DEFF Research Database (Denmark)

    Hillersdal, Line

    ask what make up food stuff and eaters in the meal tests? More specifically I explore a scientific testing of changes in taste preferences before and after weight-loss surgery using an ad libitum buffet with a selection of different foods and another testing the effect of exercise on appetite also...... an eater who: ”shouldn't restrain herself”. Practices of food and eating in the test meal I suggest, will allow us to tackle reductionism by showing the complex cultural context shaping clinical intervention....

  18. Value-Added Exchange Rates

    OpenAIRE

    Rudolfs Bems; Robert C. Johnson

    2012-01-01

    This paper updates the conceptual foundations for measuring real effective exchange rates (REERs) to allow for vertical specialization in trade. We derive a value-added REER describing how demand for the value added that a country produces changes as the price of its value added changes relative to competitors. We then compute this index for 42 countries from 1970-2009 using trade measured in value added terms and GDP deflators. There are substantial differences between value-added and conven...

  19. An $xp$ model on $AdS_2$ spacetime

    CERN Document Server

    Molina-Vilaplana, Javier

    2013-01-01

    In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, equal in magnitude, given by a harmonic oscillator with a zero point energy parameterized by the AdS radius, measured in units of a fundamental length of the model. We also construct the generators of the isometry group SO(2,1) of the AdS$_2$ spacetime, and discuss the relation with conformal quantum mechanics.

  20. 酸性天然凝胶电泳法研究HIV进入抑制剂ADS-J1的作用机制%Acid native polyacrylamide gel electrophoresis:a method for studying the mechanism of action of HIV entry inhibitor ADS-J1

    Institute of Scientific and Technical Information of China (English)

    毛芹超; 王洪涛; 李旭桂; 夏承来; 姜世勃; 刘叔文

    2010-01-01

    目的 ADS-J1是通过虚拟筛选从20 000个化合物中获得的靶向HIV gp41的小分子HIV进入抑制剂.该研究探讨ADS-J1与gp41的结合位点和作用机制.方法 采用酸性天然聚丙烯酰胺凝胶电泳技术(AN-PAGE),研究ADS-J1与衍生于gp41不同功能区的多肽的结合.结果 此前采用的天然聚丙烯酰胺凝胶电泳(N-PAGE)等方法,由于不能显示衍生于gp41的N-端多肽,未能确定ADS-J1的作用位点.该研究建立的AN-PAGE技术,能直接显示N-端多肽的条带,证实ADS-J1能与gp41的N-端螺旋重复序列(NHR)复合螺旋核中的深穴结合,从而抑制gp41六螺旋束结构的形成,而且深穴中第574位的赖氨酸残基(K574)与ADS-J1的抑制作用密切相关.结论 ADS-J1通过与gp41 NHR靶穴中的K574结合,抑制gp41六螺旋束结构的形成,从而抑制HIV进入靶细胞.此外,该研究建立的AN-PAGE技术,为研究靶向Ⅰ型包膜病毒的病毒进入抑制剂的作用机制提供了一个简便有效的实验方法.

  1. Wireless Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Hong-Chuan Yang

    2007-01-01

    Full Text Available We study the energy-efficient configuration of multihop paths with automatic repeat request (ARQ mechanism in wireless ad hoc networks. We adopt a cross-layer design approach and take both the quality of each radio hop and the battery capacity of each transmitting node into consideration. Under certain constraints on the maximum tolerable transmission delay and the required packet delivery ratio, we solve optimization problems to jointly schedule the transmitting power of each transmitting node and the retransmission limit over each hop. Numerical results demonstrate that the path configuration methods can either significantly reduce the average energy consumption per packet delivery or considerably extend the average lifetime of the multihop route.

  2. Dressing phases of AdS3/CFT2

    CERN Document Server

    Borsato, Riccardo; Sfondrini, Alessandro; Stefanski, Bogdan; Torrielli, Alessandro

    2013-01-01

    We determine the all-loop dressing phases of the AdS3/CFT2 integrable system related to type IIB string theory on AdS3 x S3 x T4 by solving the recently found crossing relations and studying their singularity structure. The two resulting phases present a novel structure with respect to the ones appearing in AdS5/CFT4 and AdS4/CFT3. In the strongly-coupled regime, their leading order reduces to the universal Arutyunov-Frolov-Staudacher phase as expected. We also compute their sub-leading order and compare it with recent one-loop perturbative results, and co

  3. Dressing phases of AdS3/CFT2

    Science.gov (United States)

    Borsato, Riccardo; Ohlsson Sax, Olof; Sfondrini, Alessandro; Stefański, Bogdan, Jr.; Torrielli, Alessandro

    2013-09-01

    We determine the all-loop dressing phases of the AdS3/CFT2 integrable system related to type IIB string theory on AdS3×S3×T4 by solving the recently found crossing relations and studying their singularity structure. The two resulting phases present a novel structure with respect to the ones appearing in AdS5/CFT4 and AdS4/CFT3. In the strongly coupled regime, their leading order reduces to the universal Arutyunov-Frolov-Staudacher phase as expected. We also compute their subleading order and compare it with recent one-loop perturbative results and comment on their weak-coupling expansion.

  4. Quantum Field Theory and Unification in AdS5

    CERN Document Server

    Randall, Lisa; Randall, Lisa; Schwartz, Matthew D.

    2001-01-01

    We consider gauge bosons in the bulk of AdS5 in a two-brane theory that addresses the hierarchy problem. We show such a theory can be consistent with gauge coupling unification at a high scale. We discuss subtleties in this calculation and show how to regulate consistently in a bounded AdS5 background. Our regularization is guided by the holographic dual of the calculation.

  5. Chaos and hydrodynamics near AdS$_2$

    CERN Document Server

    Jensen, Kristan

    2016-01-01

    We revisit AdS$_2$ holography with the Sachdev-Ye-Kitaev models in mind. Our main result is to rewrite a generic theory of gravity near an AdS$_2$ throat as a novel hydrodynamics coupled to the correlation functions of a conformal quantum mechanics. This gives a prescription for the computation of $n$-point functions in the dual quantum mechanics. We thereby find that the dual is maximally chaotic.

  6. 单宁酸与麦胶蛋白结合反应的研究%Study on the Complexation Interaction of Tannic Acid with Gliadin

    Institute of Scientific and Technical Information of China (English)

    寇正福; 刘坐镇; 邬行彦

    2003-01-01

    以单宁酸和麦胶蛋白分别作为引起啤酒浑浊的敏感多酚和敏感蛋白的模型物质,用分光光度法对影响单宁酸与麦胶蛋白结合反应的因素进行了研究.发现,麦胶蛋白的浓度影响单宁酸与麦胶蛋白结合的方式,也影响二者的结合比例.反应温度越低、反应时间越长,单宁酸与麦胶蛋白结合反应越完全.在很低的pH值时,单宁酸与麦胶蛋白结合能力很差,在pH4.0附近,单宁酸与麦胶蛋白结合反应较完全.低乙醇浓度下,随着乙醇浓度的上升,单宁酸与麦胶蛋白结合反应程度有所下降,而在较高乙醇浓度下却随之增大.

  7. Supersymmetry of AdS and flat IIB backgrounds

    Science.gov (United States)

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2015-02-01

    We present a systematic description of all warped AdS n × w M 10- n and IIB backgrounds and identify the a priori number of supersymmetries N preserved by these solutions. In particular, we find that the AdS n backgrounds preserve for n ≤ 4 and for 4 < n ≤ 6 supersymmetries and for suitably restricted. In addition under some assumptions required for the applicability of the maximum principle, we demonstrate that the Killing spinors of AdS n backgrounds can be identified with the zero modes of Dirac-like operators on M 10- n establishing a new class of Lichnerowicz type theorems. Furthermore, we adapt some of these results to backgrounds with fluxes by taking the AdS radius to infinity. We find that these backgrounds preserve for 2 < n ≤ 4 and for 4 < n ≤ 7 supersymmetries. We also demonstrate that the Killing spinors of AdS n × w M 10- n do not factorize into Killing spinors on AdS n and Killing spinors on M 10- n .

  8. ad hoc networks

    Directory of Open Access Journals (Sweden)

    Blanca Alicia Correa

    2007-01-01

    Full Text Available Los métodos de agrupamiento permiten que las MANET (redes móviles ad hoc presenten un mejor desempeño en cuanto a la rapidez de conexión, el enrutamiento y el manejo de la topología. En este trabajo se presenta una revisión sobre las técnicas de agrupamiento para MANET. Se introducen algunos temas preliminares que forman la base para el desarrollo de los algoritmos de agrupamiento, tales como: la topología de la red, el enrutamiento, la teoría de grafos y los algoritmos de movilidad. Adicionalmente, se describen algunas de las técnicas de agrupamiento más conocidas como Lowest-ID heuristic, Highest degree heuristic, DMAC (distributed mobility-adaptive clustering, WCA (weighted clustering algorithm, entre otros. El propósito central es ilustrar los conceptos principales respecto a las técnicas de agrupamiento en MANET.

  9. Action growth for AdS black holes

    Science.gov (United States)

    Cai, Rong-Gen; Ruan, Shan-Ming; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui

    2016-09-01

    Recently a Complexity-Action (CA) duality conjecture has been proposed, which relates the quantum complexity of a holographic boundary state to the action of a Wheeler-DeWitt (WDW) patch in the anti-de Sitter (AdS) bulk. In this paper we further investigate the duality conjecture for stationary AdS black holes and derive some exact results for the growth rate of action within the Wheeler-DeWitt (WDW) patch at late time approximation, which is supposed to be dual to the growth rate of quantum complexity of holographic state. Based on the results from the general D-dimensional Reissner-Nordström (RN)-AdS black hole, rotating/charged Bañados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a universal formula for the action growth expressed in terms of some thermodynamical quantities associated with the outer and inner horizons of the AdS black holes. And we leave the conjecture unchanged that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  10. AdS_5 Black Holes with Fermionic Hair

    CERN Document Server

    Burrington, B A; Sabra, W A; Burrington, Benjamin A.; Liu, James T.

    2004-01-01

    The study of new BPS objects in AdS_5 has led to a deeper understanding of AdS/CFT. To help complete this picture, and to fully explore the consequences of the supersymmetry algebra, it is also important to obtain new solutions with bulk fermions turned on. In this paper we construct superpartners of the 1/2 BPS black hole in AdS_5 using a natural set of fermion zero modes. We demonstrate that these superpartners, carrying fermionic hair, have conserved charges differing from the original bosonic counterpart. To do so, we find the R-charge and dipole moment of the new system, as well as the mass and angular momentum, defined through the boundary stress tensor. The complete set of superpartners fits nicely into a chiral representation of AdS_5 supersymmetry, and the spinning solutions have the expected gyromagnetic ratio, g=1.

  11. Complexity Growth for AdS Black Holes

    CERN Document Server

    Cai, Rong-Gen; Wang, Shao-Jiang; Yang, Run-Qiu; Peng, Rong-Hui

    2016-01-01

    We further investigate the Complexity-Action (CA) duality conjecture for stationary anti de-Sitter (AdS) black holes and derive some exact results for the growth rate of action within Wheeler-DeWitt (WDW) patch at late time approximation, which is dual to the growth rate of quantum complexity of holographic state. Based on the results from the general $D$-dimensional Reissner-Nordstr\\"{o}m (RN)-AdS black hole, rotating/charged Ba\\~{n}ados-Teitelboim-Zanelli (BTZ) black hole, Kerr-AdS black hole and charged Gauss-Bonnet-AdS black hole, we present a new complexity bound but leave unchanged the conjecture that the stationary AdS black hole in Einstein gravity is the fastest computer in nature.

  12. Drug: D04709 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D04709 Mixture, Drug Scopolia extract and tannic acid suppositories (JP16); Scopolia extract... and tannic acid (TN) Scopolia extract [DR:D04062], Tannic acid [DR:D01959] Therapeutic category: 2...nd anal organ agents 255 Hemorrhoidal preparations 2559 Others D04709 Scopolia extract and tannic acid suppositories (JP16) PubChem: 17398146 ...

  13. Constructing the AdS dual of a Fermi liquid: AdS Black holes with Dirac hair

    CERN Document Server

    \\vCubrović, Mihailo; Schalm, Koenraad

    2010-01-01

    We provide new evidence that the holographic dual to a strongly coupled charged Fermi Liquid has a non-zero fermion density in the bulk. We show that the pole-strength of the stable quasiparticle characterizing the Fermi surface is encoded in the spatially averaged AdS probability density of a single normalizable fermion wavefunction in AdS. Recalling Migdal's theorem which relates the pole strength to the Fermi-Dirac characteristic discontinuity in the number density at $\\ome_F$, we conclude that the AdS dual of a Fermi liquid is described by occupied on-shell fermionic modes in AdS. Encoding the occupied levels in the total probability density of the fermion field directly, we show that an AdS Reissner-Nordstr\\"{o}m black hole in a theory with charged fermions has a critical temperature, at which the system undergoes a first-order transition to a black hole with a non-vanishing profile for the bulk fermion field. Thermodynamics and spectral analysis confirm that the solution with non-zero AdS fermion-profil...

  14. 膨润土改善鸡粪厌氧消化产酸产甲烷特性%Improving production characteristics of methane and organic acid during anaerobic batch digestion of poultry manure by adding bentonite

    Institute of Scientific and Technical Information of China (English)

    潘君廷; 马俊怡; 郜天磊; 邱凌; 刘宏斌

    2016-01-01

    There were approximately 20 billion chickens in the world in 2010, with 23% of the chicken population found in China. In 2009, the rapid development of chicken farms in China resulted in the production of 126 million tons of poultry manure. If managed inappropriately, poultry manure can cause serious environmental problems by polluting water, air, and soil. Anaerobic digestion is a complex bioconversion process that can treat organic waste and generate biogas with a high methane content that can be used as renewable energy, hence reducing the consumption of fossil fuel and curtailing greenhouse gas emissions. Ca2+-betonite is an environmental friendly material and is widely used in compost, heavy metal removal, pollutant adsorption, etc. In order to investigate the effect of betonite addition on anaerobic digestion of poultry manure, an orthogonal experiment L8(23)was conducted to determine amount of poultry manure (organic loading rate (OLR)), amount of bentonite and inoculum concentration on characteristics of methane production and organic acid production during anaerobic batch digestion of poultry manure under mesophilic condition (35±1)℃. The results showed that bentonite addition could significantly increase methane production per VS by 22.72% and 27.72% with 3.0% and 1.5% betonite addition (based on poultry manure total solids), respectively compared to the control group under low OLR condition. Methane production from poultry manure with 3.0% or 1.5% betonite addition had no significant (P>0.05) difference under low OLR condition. Specifically, methane production could be very significantly (P<0.05) increased by adding betonite under high OLR condition. Methane production was increased by 78.68% and 55.41% with 3.0% and 1.5% betonite addition, respectively, compared to the control group under high OLR condition. Methane production from poultry manure with 3.0% or 1.5% betonite addition had significant (P<0.05) difference under high OLR condition. In the

  15. Global geometric properties of AdS space and the AdS/CFT correspondence

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Poisson kernels and relations between them for a massive scalar field in a unit ball Bn with Hua's metric and conformal flat metric are obtained by describing the Bn as a submanifold of an (n+1)-dimensional embedding space. Global geometric properties of the AdS space are discussed. We show that the(n+1)-dimensional AdS space AdSn+1 is isomorphic to RP1×Bn and boundary of the AdS is isomorphic to RP1×Sn-1. Bulk-boundary propagator and the AdS/CFT like correspondence are demonstrated based on these global geometric properties of the RP1×Bn.

  16. Different views of AEGIS / AD-6 Experiment (AD facility) AD-6

    CERN Multimedia

    Maximilien Brice

    2012-01-01

    Different views of AEGIS / AD-6 Experiment (AD facility) in July of 2012. The visible parts are the positron accumulator (blue structures on top of of the antiproton extraction line) and the 5T magnet which traps the antiprotons.

  17. AdS-Carroll Branes

    CERN Document Server

    Clark, T E

    2016-01-01

    Coset methods are used to determine the action of a co-dimension one brane (domain wall) embedded in (d+1)-dimensional AdS space in the Carroll limit in which the speed of light goes to zero. The action is invariant under the non-linearly realized symmetries of the AdS-Carroll spacetime. The Nambu-Goldstone field exhibits a static spatial distribution for the brane with a time varying momentum density related to the brane's spatial shape as well as the AdS-C geometry. The AdS-C vector field dual theory is obtained.

  18. Doubly Dynamic Self-Healing Materials Based on Oxime Click Chemistry and Boronic Acids.

    Science.gov (United States)

    Collins, Joe; Nadgorny, Milena; Xiao, Zeyun; Connal, Luke A

    2017-03-01

    The dynamic covalent characteristics of oxime and boronate ester bonds have been explored. A small excess of a competing aldehyde under acidic conditions resulted in oxime polymer degradation from high molecular weights (30 kDa) to low molecular weight oligomers (2.2 kDa). The dynamic nature of oxime bonds imparts oxime cross-linked hydrogels with self-healing properties and the incorporation of phenyl boronic acid groups into the hydrogel network provides a platform for hydrogel functionalization. The addition of a polyphenol (tannic acid) proves a facile means to incorporate a second, dynamic covalent cross-linking network through boronate ester formation which, owing to the increase in the degree of cross-linking, is found to be nearly double the hydrogel strength (storage modulus increased from 4.6 to 8.5 kPa). Finally, the tannic acid cross-linking network is selectively degraded returning the hydrogel storage modulus to its initial value and providing a means for the synthesis of materials with tunable mechanical properties. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Effects of Adding Fermented Green Juice and Sorbic Acid on the Fermentation Quafity of Hunnigreen Forage Sorghum Silage%添加绿汁发酵液和山梨酸对“大力士”饲用甜高粱青贮品质的影响研究

    Institute of Scientific and Technical Information of China (English)

    林仕欣; 高承芳; 刘远; 张晓佩; 李文杨; 董晓宁

    2012-01-01

    This study was carried out to evaluate the effects of adding fermented green juice and sorbic acid on the fermentation quality of Hunnigreen forage Sorghum silage. The treatments were as follows: control, PFJ addition, sorbic acid addition, PFJ + sorbic acid on the fresh weight basis of Hunnigreen forage Sorghum, respectively. The materials were ensiled at normal temperature and opened 60 days later. Then the fermentation quality and chemical composition of silages were analyzed. Based on results, adding PFJ, sorbic acid and PFJ+sorbic acid could significantly decreased pH, ammonia nitrogen content and the lost of gas and improved the lactic acid content, water soluble carbohydrate and dry matter recovery (P<0.05=. The results showed that adding PFJ, sorbic acid and PFJ+sorbic acid could significantly improved fermentation quality of Hunnigreen forage Sorghum silage.%为探讨绿汁发酵液和山梨酸对“大力士”饲用甜高粱青贮饲料品质的影响.试验设对照组、绿汁发酵液组、山梨酸组及绿汁发酵液+山梨酸组,常温下贮存60天后开窖取样,测定其发酵品质与化学成分.结果表明:添加绿汁发酵液、山梨酸及绿汁发酵液+山梨均可显著降低“大力士”饲用甜高粱青贮饲料的pH值、氨态氮含量和气体损失率(P<0.05),提高乳酸含量、水溶性碳水化合物含量和干物质回收率(P<0.05).表明添加绿汁发酵液、山梨酸及绿汁发酵液+山梨酸均可显著改善“大力士”饲用甜高粱的青贮品质.

  20. Inhibitory effect of ethanol, acetic acid, propionic acid and butyric acid on fermentative hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bo; Wan, Wei; Wang, Jianlong [Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084 (China)

    2008-12-15

    The inhibitory effect of added ethanol, acetic acid, propionic acid and butyric acid on fermentative hydrogen production by mixed cultures was investigated in batch tests using glucose as substrate. The experimental results showed that, at 35 C and initial pH 7.0, during the fermentative hydrogen production, the substrate degradation efficiency, hydrogen production potential, hydrogen yield and hydrogen production rate all trended to decrease with increasing added ethanol, acetic acid, propionic acid and butyric acid concentration from 0 to 300 mmol/L. The inhibitory effect of added ethanol on fermentative hydrogen production was smaller than those of added acetic acid, propionic acid and butyric acid. The modified Han-Levenspiel model could describe the inhibitory effects of added ethanol, acetic acid, propionic acid and butyric acid on fermentative hydrogen production rate in this study successfully. The modified Logistic model could describe the progress of cumulative hydrogen production. (author)

  1. Entanglement entropy for free scalar fields in AdS

    CERN Document Server

    Sugishita, Sotaro

    2016-01-01

    We compute entanglement entropy for free massive scalar fields in anti-de Sitter (AdS) space. The entangling surface is a minimal surface whose boundary is a sphere at the boundary of AdS. The entropy can be evaluated from the thermal free energy of the fields on a topological black hole by using the replica method. In odd-dimensional AdS, exact expressions of the Renyi entropy S_n are obtained for arbitrary n. We also evaluate 1-loop corrections coming from the scalar fields to holographic entanglement entropy. Applying the results, we compute the leading difference of entanglement entropy between two holographic CFTs related by a renormalization group flow triggered by a double trace deformation. The difference is proportional to the shift of a central charge under the flow.

  2. Microstates at the boundary of AdS

    CERN Document Server

    Mathur, Samir D

    2011-01-01

    The bound states of the D1D5 brane system have a known gravitational description: flat asymptotics, an anti-de Sitter region, and a 'cap' ending the AdS region. We construct perturbations that correspond to the action of chiral algebra generators on Ramond ground states of D1D5 branes. Abstract arguments in the literature suggest that the perturbation should be pure gauge in the AdS region; our perturbation indeed has this structure, with the nontrivial deformation of the geometry occurring at the 'neck' between the AdS region and asymptotic infinity. This 'non-gauge' deformation is needed to provide the nonzero energy and momentum carried by the perturbation. We also suggest implications this structure may have for the majority of microstates which live at the cap.

  3. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    CERN Document Server

    Evnin, Oleg

    2016-01-01

    We present a range of methods suitable for accurate evaluation of the leading asymptotics for integrals of products of Jacobi polynomials in limits when the degrees of some or all polynomials inside the integral become large. The structures in question have recently emerged in the context of effective descriptions of small amplitude perturbations in anti-de Sitter (AdS) spacetime. The limit of high degree polynomials corresponds in this situation to effective interactions involving extreme short-wavelength modes, whose dynamics is crucial for the turbulent instabilities that determine the ultimate fate of small AdS perturbations. We explicitly apply the relevant asymptotic techniques to the case of a self-interacting probe scalar field in AdS and extract a detailed form of the leading large degree behavior, including closed form analytic expressions for the numerical coefficients appearing in the asymptotics.

  4. Detailed ultraviolet asymptotics for AdS scalar field perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Jai-akson, Puttarak [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand)

    2016-04-11

    We present a range of methods suitable for accurate evaluation of the leading asymptotics for integrals of products of Jacobi polynomials in limits when the degrees of some or all polynomials inside the integral become large. The structures in question have recently emerged in the context of effective descriptions of small amplitude perturbations in anti-de Sitter (AdS) spacetime. The limit of high degree polynomials corresponds in this situation to effective interactions involving extreme short-wavelength modes, whose dynamics is crucial for the turbulent instabilities that determine the ultimate fate of small AdS perturbations. We explicitly apply the relevant asymptotic techniques to the case of a self-interacting probe scalar field in AdS and extract a detailed form of the leading large degree behavior, including closed form analytic expressions for the numerical coefficients appearing in the asymptotics.

  5. Asymptotically AdS spacetimes with a timelike Kasner singularity

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Jie [Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel)

    2016-07-21

    Exact solutions to Einstein’s equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution’s appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.

  6. Asymptotically AdS spacetimes with a timelike Kasner singularity

    Science.gov (United States)

    Ren, Jie

    2016-07-01

    Exact solutions to Einstein's equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution's appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.

  7. Revisiting the thermodynamic relations in AdS /CMT models

    Science.gov (United States)

    Hyun, Seungjoon; Park, Sang-A.; Yi, Sang-Heon

    2017-03-01

    Motivated by the recent unified approach to the Smarr-like relation of anti-de Sitter (AdS) planar black holes in conjunction with the quasilocal formalism on conserved charges, we revisit the quantum statistical and thermodynamic relations of hairy AdS planar black holes. By extending the previous results, we identify the hairy contribution in the bulk and show that the holographic computation can be improved so that it is consistent with the bulk computation. We argue that the first law can be retained in its universal form and that the relation between the on-shell renormalized Euclidean action and its free energy interpretation in gravity may also be undeformed even with the hairy contribution in hairy AdS black holes.

  8. Mapping AdS to dS and back

    CERN Document Server

    Di Dato, Adriana

    2014-01-01

    We derive a map between Einstein spaces of positive and negative curvature. Starting from a space of positive curvature with some dimensions compactified on a sphere and analytically continuing the number of compact dimensions, we obtain a space of negative curvature with a compact hyperbolic subspace, and vice versa. Prime examples of such spaces are de Sitter and Anti-de Sitter space, as well as black hole spacetimes with (A)dS asymptotics and perturbed versions thereof, which play an important role in holography. This map extends work done by Caldarelli et.al., who map asymptotically AdS spaces to Ricci-flat ones. A remarkable result is that the boundary of asymptotically AdS spaces is mapped to a brane in the bulk of de Sitter, and perturbations near the AdS boundary are sourced by a stress tensor confined to this brane. We also calculate the Brown-York stress tensor for the perturbed AdS metric, which turns out to be the negative of the stress tensor on the de Sitter brane.

  9. An $xp$ model on $AdS_2$ spacetime

    OpenAIRE

    2012-01-01

    In this paper we formulate the $xp$ model on the AdS$_2$ spacetime. We find that the spectrum of the Hamiltonian has positive and negative eigenvalues, whose absolute values are given by a harmonic oscillator spectrum, which in turn coincides with that of a massive Dirac fermion in AdS$_2$. We extend this result to generic $xp$ models which are shown to be equivalent to a massive Dirac fermion on spacetimes whose metric depend of the $xp$ Hamiltonian. Finally, we construct the generators of t...

  10. AdS5 magnetized solutions in minimal gauged supergravity

    Directory of Open Access Journals (Sweden)

    Jose Luis Blázquez-Salcedo

    2017-08-01

    Full Text Available We construct a generalization of the AdS charged rotating black holes with two equal magnitude angular momenta in five-dimensional minimal gauged supergravity. In addition to the mass, electric charge and angular momentum, the new solutions possess an extra-parameter associated with a non-zero magnitude of the magnetic potential at infinity. In contrast with the known cases, these new black holes possess a non-trivial zero-horizon size limit which describes a one parameter family of spinning charged solitons. All configurations reported in this work approach asymptotically an AdS5 spacetime in global coordinates and are free of pathologies.

  11. Diffusion and Chaos from near AdS$_2$ horizons

    CERN Document Server

    Blake, Mike

    2016-01-01

    We calculate the thermal diffusivity $D = \\kappa/c_{\\rho}$ and butterfly velocity $v_B$ in holographic models that flow to AdS$_2 \\times R^{d}$ fixed points in the infra-red. We show that both these quantities are governed by the same irrelevant deformation of AdS$_2$ and hence establish a simple relationship between them. When this deformation corresponds to a universal dilaton mode of dimension $\\Delta = 2$ then this relationship is always given by $D = v_B^2/(2 \\pi T)$.

  12. Gallic Acid Production with Mouldy Polyurethane Particles Obtained from Solid State Culture of Aspergillus niger GH1.

    Science.gov (United States)

    Mata-Gómez, Marco; Mussatto, Solange I; Rodríguez, Raul; Teixeira, Jose A; Martinez, Jose L; Hernandez, Ayerim; Aguilar, Cristóbal N

    2015-06-01

    Gallic acid production in a batch bioreactor was evaluated using as catalytic material the mouldy polyurethane solids (MPS) obtained from a solid-state fermentation (SSF) bioprocess carried out for tannase production by Aspergillus niger GH1 on polyurethane foam powder (PUF) with 5 % (v/w) of tannic acid as inducer. Fungal biomass, tannic acid consumption and tannase production were kinetically monitored. SSF was stopped when tannase activity reached its maximum level. Effects of washing with distilled water and drying on the tannase activity of MPS were determined. Better results were obtained with dried and washed MPS retaining 84 % of the tannase activity. Maximum tannase activity produced through SSF after 24 h of incubation was equivalent to 130 U/gS with a specific activity of 36 U/mg. The methylgallate was hydrolysed (45 %) in an easy, cheap and fast bioprocess (30 min). Kinetic parameters of tannase self-immobilized on polyurethane particles were calculated to be 5 mM and 04.1 × 10(-2) mM/min for K M and V max, respectively. Results demonstrated that the MPS, with tannase activity, can be successfully used for the production of the antioxidant gallic acid from methyl-gallate substrate. Direct use of PMS to produce gallic acid can be advantageous as no previous extraction of enzyme is required, thus reducing production costs.

  13. Penrose inequality for asymptotically AdS spaces

    Energy Technology Data Exchange (ETDEWEB)

    Itkin, Igor [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel); Oz, Yaron, E-mail: yaronoz@post.tau.ac.il [Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978 (Israel)

    2012-02-28

    In general relativity, the Penrose inequality relates the mass and the entropy associated with a gravitational background. If the inequality is violated by an initial Cauchy data, it suggests a creation of a naked singularity, thus providing means to consider the cosmic censorship hypothesis. We propose a general form of Penrose inequality for asymptotically locally AdS spaces.

  14. Internet Advertising. Google AdWords versus Facebook Ads

    Directory of Open Access Journals (Sweden)

    Paul PAŞCU

    2014-05-01

    Full Text Available This article describes how to use the applications for Internet advertising, Google AdWords and Facebook Ads. Our attempt is to present the advantages and disadvantages of each of them, the costs and benefits, a useful aspect for companies that plan to start advertising campaigns on the Internet.

  15. Predicting AD conversion: comparison between prodromal AD guidelines and computer assisted PredictAD tool.

    Directory of Open Access Journals (Sweden)

    Yawu Liu

    Full Text Available To compare the accuracies of predicting AD conversion by using a decision support system (PredictAD tool and current research criteria of prodromal AD as identified by combinations of episodic memory impairment of hippocampal type and visual assessment of medial temporal lobe atrophy (MTA on MRI and CSF biomarkers.Altogether 391 MCI cases (158 AD converters were selected from the ADNI cohort. All the cases had baseline cognitive tests, MRI and/or CSF levels of Aβ1-42 and Tau. Using baseline data, the status of MCI patients (AD or MCI three years later was predicted using current diagnostic research guidelines and the PredictAD software tool designed for supporting clinical diagnostics. The data used were 1 clinical criteria for episodic memory loss of the hippocampal type, 2 visual MTA, 3 positive CSF markers, 4 their combinations, and 5 when the PredictAD tool was applied, automatically computed MRI measures were used instead of the visual MTA results. The accuracies of diagnosis were evaluated with the diagnosis made 3 years later.The PredictAD tool achieved the overall accuracy of 72% (sensitivity 73%, specificity 71% in predicting the AD diagnosis. The corresponding number for a clinician's prediction with the assistance of the PredictAD tool was 71% (sensitivity 75%, specificity 68%. Diagnosis with the PredictAD tool was significantly better than diagnosis by biomarkers alone or the combinations of clinical diagnosis of hippocampal pattern for the memory loss and biomarkers (p≤0.037.With the assistance of PredictAD tool, the clinician can predict AD conversion more accurately than the current diagnostic criteria.

  16. AdS5 backgrounds with 24 supersymmetries

    Science.gov (United States)

    Beck, S.; Gutowski, J.; Papadopoulos, G.

    2016-06-01

    We prove a non-existence theorem for smooth AdS 5 solutions with connected, compact without boundary internal space that preserve strictly 24 supersymmetries. In particular, we show that D = 11 supergravity does not admit such solutions, and that all such solutions of IIB supergravity are locally isometric to the AdS 5 × S 5 maximally supersymmetric background. Furthermore, we prove that (massive) IIA supergravity also does not admit such solutions, provided that the homogeneity conjecture for massive IIA supergravity is valid. In the context of AdS/CFT these results imply that if gravitational duals for strictly mathcal{N}=3 superconformal theories in 4-dimensions exist, they are either singular or their internal spaces are not compact.

  17. Coset construction of AdS particle dynamics

    CERN Document Server

    Heinze, Martin; Megrelidze, Luka

    2016-01-01

    We analyze dynamics of the AdS$_{N+1}$ particle realized on the coset SO$(2,N)/$SO$(1,N)$. Hamiltonian reduction provides the physical phase space in terms of the coadjoint orbit obtained by boosting a timelike element of ${\\frak so}(2,N)$. We show equivalence of this approach to geometric quantization and to the SO$(N)$ covariant oscillator description, for which the boost generators entail a complicated operator ordering. As an alternative scheme, we introduce dual oscillator variables and derive their algebra at the classical and the quantum level. This simplifies the calculations of the commutators for the boost generators and leads to unitary irreducible representations of ${\\frak so}(2,N)$ for all admissible values of the mass parameter. We furthermore discuss a SO$(N)$ covariant supersymmetric extensions of the oscillator quantization, with its realization for superparticles in AdS$_2$ and AdS$_3$ given by recent works.

  18. Sub-AdS Scale Locality in AdS$_3$/CFT$_2$

    CERN Document Server

    Belin, Alexandre; Jefferson, Robert A; Kabir, Laurens

    2016-01-01

    We investigate sub-AdS scale locality in a weakly coupled toy model of the AdS$_3$/CFT$_2$ correspondence. We find that this simple model has the correct density of states at low and high energies to be dual to Einstein gravity coupled to matter in AdS$_3$. Bulk correlation functions also have the correct behavior at leading order in the large $N$ expansion, but non-local effects emerge at order $1/N$. Our analysis leads to the conjecture that any large $N$ CFT$_2$ that is modular invariant and has the right low-energy density of states is dual to a gravitational theory with sub-AdS scale locality.

  19. Ultraviolet asymptotics for quasiperiodic AdS_4 perturbations

    CERN Document Server

    Craps, Ben; Jai-akson, Puttarak; Vanhoof, Joris

    2015-01-01

    Spherically symmetric perturbations in AdS-scalar field systems of small amplitude epsilon approximately periodic on time scales of order 1/epsilon^2 (in the sense that no significant transfer of energy between the AdS normal modes occurs) have played an important role in considerations of AdS stability. They are seen as anchors of stability islands where collapse of small perturbations to black holes does not occur. (This collapse, if it happens, typically develops on time scales of the order 1/epsilon^2.) We construct an analytic treatment of the frequency spectra of such quasiperiodic perturbations, paying special attention to the large frequency asymptotics. For the case of a self-interacting phi^4 scalar field in a non-dynamical AdS background, we arrive at a fairly complete analytic picture involving quasiperiodic spectra with an exponential suppression modulated by a power law at large mode numbers. For the case of dynamical gravity, the structure of the large frequency asymptotics is more complicated....

  20. Frozen yogurt with added inulin and isomalt.

    Science.gov (United States)

    Isik, U; Boyacioglu, D; Capanoglu, E; Erdil, D Nilufer

    2011-04-01

    The objective of this study was to produce a frozen yogurt containing low fat and no added sugar. Samples containing 5% polydextrose, 0.065% aspartame and acesulfame-K mixture, and different levels of inulin and isomalt (5.0, 6.5, and 8.0%) were produced at pilot scale and analyzed for their physical and chemical properties including proximate composition, viscosity, acidity, overrun, melting rate, heat shock stability, as well as sensory characteristics, and viability of lactic acid bacteria. With the addition of inulin and isomalt, viscosity increased by 19 to 52% compared with that of sample B (reduced-fat control). The average calorie values of samples substituted with sweeteners were about 43% lower than that of original sample. Low-calorie frozen yogurt samples melted about 33 to 48% slower than the reduced-fat control sample at 45 min. Based on quantitative descriptive profile test results, statistically significant differences among products were observed for hardness, iciness, foamy melting, whey separation, and sweetness characteristics. The results of principal component analysis showed that the sensory properties of the sample containing 6.5% inulin and 6.5% isomalt were similar to those of control. Lactic acid bacteria counts of frozen yogurt were found to be between 8.12 and 8.49 log values, 3 mo after the production. The overall results showed that it is possible to produce an attractive frozen yogurt product with the incorporation of inulin and isomalt with no added sugar and reduced fat.

  1. AdS nonlinear instability: moving beyond spherical symmetry

    CERN Document Server

    Dias, Oscar J C

    2016-01-01

    Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation [1,2]. We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied in [2]. In contrast with [2], we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied in [2]. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of [2]. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.

  2. Universal isolation in the AdS landscape

    Science.gov (United States)

    Danielsson, U. H.; Dibitetto, G.; Vargas, S. C.

    2016-12-01

    We study the universal conditions for quantum nonperturbative stability against bubble nucleation for pertubatively stable AdS vacua based on positive energy theorems. We also compare our analysis with the preexisting ones in the literature carried out within the thin-wall approximation. The aforementioned criterion is then tested in two explicit examples describing massive type IIA string theory compactified on S3 and S3×S3, respectively. The AdS landscape of both classes of compactifications is known to consist of a set of isolated points. The main result is that all critical points respecting the Breitenlohner-Freedman (BF) bound also turn out be stable at a nonperturbative level. Finally, we speculate on the possible universal features that may be extracted from the above specific examples.

  3. The Mixed Phase of Charged AdS Black Holes

    Directory of Open Access Journals (Sweden)

    Piyabut Burikham

    2016-01-01

    Full Text Available We study the mixed phase of charged AdS black hole and radiation when the total energy is fixed below the threshold to produce a stable charged black hole branch. The coexistence conditions for the charged AdS black hole and radiation are derived for the generic case when radiation particles carry charge. The phase diagram of the mixed phase is demonstrated for both fixed potential and charge ensemble. In the dual gauge picture, they correspond to the mixed phase of quark-gluon plasma (QGP and hadron gas in the fixed chemical potential and density ensemble, respectively. In the nuclei and heavy-ion collisions at intermediate energies, the mixed phase of exotic QGP and hadron gas could be produced. The mixed phase will condense and evaporate into the hadron gas as the fireball expands.

  4. Smoothed Transitions in Higher Spin AdS Gravity

    CERN Document Server

    Banerjee, Shamik; Hellerman, Simeon; Hijano, Eliot; Lepage-Jutier, Arnaud; Maloney, Alexander; Shenker, Stephen

    2012-01-01

    We consider CFTs conjectured to be dual to higher spin theories of gravity in AdS_3 and AdS_4. Two dimensional CFTs with W_N symmetry are considered in the lambda=0 (k --> infinity) limit, where they are conjectured to be described by continuous orbifolds. The torus partition function is computed, using reasonable assumptions, and equals that of a free field theory. We find no phase transition at temperatures of order one; the usual Hawking-Page phase transition is removed by the highly degenerate light states associated with conical defect states in the bulk. Three dimensional Chern-Simons-matter CFTs with vector-like matter are considered on T^3, where the dynamics is described by an effective theory for the eigenvalues of the holonomies. Likewise, we find no evidence for a Hawking-Page phase transition at large level k.

  5. Perturbative entanglement thermodynamics for AdS spacetime: Renormalization

    CERN Document Server

    Mishra, Rohit

    2015-01-01

    We study the effect of charged excitations in the AdS spacetime on the first law of entanglement thermodynamics. It is found that `boosted' AdS black holes give rise to a more general form of first law which includes chemical potential and charge density. To obtain this result we have to resort to a second order perturbative calculation of entanglement entropy for small size subsystems. At first order the form of entanglement law remains unchanged even in the presence of charged excitations. But the thermodynamic quantities have to be appropriately `renormalized' at the second order due to the corrections. We work in the perturbative regime where $T_{thermal}\\ll T_E$.

  6. Thermodynamics of Einstein-Proca AdS Black Holes

    CERN Document Server

    Liu, Hai-Shan; Pope, C N

    2014-01-01

    We study static spherically-symmetric solutions of the Einstein-Proca equations in the presence of a negative cosmological constant. We show that the theory admits solutions describing both black holes and also solitons in an asymptotically AdS background. Interesting subtleties can arise in the computation of the mass of the solutions and also in the derivation of the first law of thermodynamics. We make use of holographic renormalisation in order to calculate the mass, even in cases where the solutions have a rather slow approach to the asymptotic AdS geometry. By using the procedure developed by Wald, we derive the first law of thermodynamics for the black hole and soliton solutions. This includes a non-trivial contribution associated with the Proca "charge." The solutions cannot be found analytically, and so we make use of numerical integration techniques to demonstrate their existence.

  7. Note on classical string dynamics on AdS3

    Science.gov (United States)

    Bañados, Máximo; Ritz, Adam

    1999-12-01

    We consider bosonic strings propagating on Euclidean anti-de Sitter space (AdS3), and study in particular the realization of various worldsheet symmetries. We give a proper definition for the Brown-Henneaux asymptotic target space symmetry, when acting on the string action, and derive the Giveon-Kutasov-Seiberg worldsheet contour integral representation simply by using Noether's theorem. We show that making identifications in the target space is equivalent to the insertion of an (exponentiated) graviton vertex operator carrying the corresponding charge. Finally, we point out an interesting relation between 3D gravity and the dynamics of the worldsheet on AdS3. Both theories are described by an SL(2,C)/SU(2) Wess-Zumino-Witten (WZW) model, and we prove that the reduction conditions determined on one hand by worldsheet diffeomorphism invariance, and on the other by the Brown-Henneaux boundary conditions, are the same.

  8. Observing quantum gravity in asymptotically AdS space

    Science.gov (United States)

    Emelyanov, Slava

    2015-12-01

    The question is studied of whether an observer can discover quantum gravity in the semiclassical regime. It is shown that it is indeed possible to probe a certain quantum gravity effect by employing an appropriately designed detector. The effect is related to the possibility of having topologically inequivalent geometries in the path-integral approach at the same time. A conformal field theory (CFT) state which is expected to describe the eternal anti-de Sitter (AdS) black hole in the large-N limit is discussed. It is argued under certain assumptions that the black hole boundary should be merely a patch of the entire AdS boundary. This leads then to a conclusion that that CFT state is the ordinary CFT vacuum restricted to that patch. If existent, the bulk CFT operators can behave as the ordinary semiclassical quantum field theory in the large-N limit in the weak sense.

  9. Semiclassical Virasoro Blocks from AdS$_3$ Gravity

    CERN Document Server

    Hijano, Eliot; Perlmutter, Eric; Snively, River

    2015-01-01

    We present a unified framework for the holographic computation of Virasoro conformal blocks at large central charge. In particular, we provide bulk constructions that correctly reproduce all semiclassical Virasoro blocks that are known explicitly from conformal field theory computations. The results revolve around the use of geodesic Witten diagrams, recently introduced in arXiv:1508.00501, evaluated in locally AdS$_3$ geometries generated by backreaction of heavy operators. We also provide an alternative computation of the heavy-light semiclassical block -- in which two external operators become parametrically heavy -- as a certain scattering process involving higher spin gauge fields in AdS$_3$; this approach highlights the chiral nature of Virasoro blocks. These techniques may be systematically extended to compute corrections to these blocks and to interpolate amongst the different semiclassical regimes.

  10. AdS plane waves, entanglement and mutual information

    CERN Document Server

    Mukherjee, Debangshu

    2014-01-01

    $AdS$ plane wave backgrounds are dual to CFT excited states with energy momentum density $T_{++}=Q$. Building on previous work on entanglement entropy in these and nonconformal brane plane wave backgrounds, we first describe a phenomenological scaling picture for entanglement in terms of "entangling partons". We then study aspects of holographic mutual information in these backgrounds for two strip shaped subsystems, aligned parallel or orthogonal to the flux. We focus on the wide ($Ql^d\\gg 1$) and narrow ($Ql^d\\ll 1$) strip regimes. In the wide strip regime, mutual information exhibits growth with the individual strip sizes and a disentangling transition as the separation between the strips increases, whose behaviour is distinct from the ground and thermal states. In the narrow strip case, our calculations have parallels with "entanglement thermodynamics" for these $AdS$ plane wave deformations. We also discuss some numerical analysis.

  11. N=2 supersymmetric sigma-models in AdS

    CERN Document Server

    Butter, Daniel

    2011-01-01

    We construct the most general N=2 supersymmetric nonlinear sigma-model in four-dimensional anti-de Sitter (AdS) space in terms of N=1 chiral superfields. The target space is shown to be a non-compact hyperkahler manifold restricted to possess a special Killing vector field. A remarkable property of the sigma-model constructed is that the algebra of OSp(2|4) transformations is closed off the mass shell.

  12. Generalised structures for N=1 AdS backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Coimbra, André [Institut für Theoretische Physik & Center for Quantum Engineering and Spacetime Research,Leibniz Universität Hannover,Appelstraße 2, 30167 Hannover (Germany); Strickland-Constable, Charles [Institut de physique théorique, Université Paris Saclay, CEA, CNRS, Orme des Merisiers, F-91191 Gif-sur-Yvette (France)

    2016-11-16

    We expand upon a claim made in a recent paper [http://arxiv.org/abs/1411.5721] that generic minimally supersymmetric AdS backgrounds of warped flux compactifications of Type II and M theory can be understood as satisfying a straightforward weak integrability condition in the language of E{sub d(d)}×ℝ{sup +} generalised geometry. Namely, they are spaces admitting a generalised G-structure set by the Killing spinor and with constant singlet generalised intrinsic torsion.

  13. SUSY properties of warped AdS3

    Science.gov (United States)

    Jeong, Jaehoon; Colgáin, Eoin Ó.; Yoshida, Kentaroh

    2014-06-01

    We examine supersymmetric properties of null-warped AdS3, or alternatively Schrödinger geometries, dual to putative warped CFTs in two dimensions. We classify super Schrödinger subalgebras of the superalgebra psu(1, 1|2) ⊕ psu(1, 1|2), corresponding to the superconformal algebra of the AdS3 × S3 geometry. We comment on geometric realisations and provide a string theory description with enhanced supersymmetry in terms of intersecting D3-branes. For type IIB supergravity solutions based on T 1,1, we consider the relationship between five-dimensional Schrödinger solutions and their three-dimensional null-warped counterparts, corresponding to R symmetry twists. Finally, we study a family of null-warped AdS3 solutions in a setting where there is an ambiguity over the R symmetry and confirm that, for examples admitting a Kaluza-Klein (KK) reduction to three dimensions, the minimisation of a real superpotential of the three-dimensional gauged supergravity captures the central charge and R symmetry.

  14. N=2 AdS supergravity and supercurrents

    CERN Document Server

    Butter, Daniel

    2011-01-01

    We consider the minimal off-shell formulation for four-dimensional N=2 supergravity with a cosmological term, in which the second compensator is an improved tensor multiplet. We use it to derive a linearized supergravity action (and its dual versions) around the anti-de Sitter (AdS) background in terms of three N=2 off-shell multiplets: an unconstrained scalar superfield, vector and tensor multiplets. This allows us to deduce the structure of the supercurrent multiplet associated with those supersymmetric theories which naturally couple to the supergravity formulation chosen, with or without a cosmological term. Finally, our linearized N=2 AdS supergravity action is reduced to N=1 superspace. The result is a sum of two N=1 linearized actions describing (i) old minimal supergravity; and (ii) an off-shell massless gravitino multiplet. We also derive dual formulations for the massless N=1 gravitino multiplet in AdS. As a by-product of our consideration, we derive the consistent supergravity extension of the N=1 ...

  15. Effects of adding sulphuric acid on composting process of cattle manure and changes of main nutrients%添加硫酸对牛粪堆肥过程及其养分变化的影响

    Institute of Scientific and Technical Information of China (English)

    胡雨彤; 时连辉; 刘登民; 仝少伟; 魏美艳; 孙杰

    2014-01-01

    为研究不同浓度硫酸对畜禽粪便条垛式堆肥中pH值以及养分含量动态变化的影响,以牛粪和锯末为试验材料,以实验室常用浓硫酸稀释成不同浓度为添加物,在露天进行43 d的条垛式堆肥,测定堆肥过程中温度、水分、pH值、全量和速效养分含量,并以种子发芽指数测定堆肥效果。结果表明,在初始物料中添加0.2 mol/L、0.3 mol/L的硫酸对缩短堆肥高温上升期,降低堆肥pH和促进有机质分解,提高堆肥中全氮、全磷、全钾、有效磷、速效钾含量具有明显效果。其中添加0.2 mol/L硫酸堆体在堆肥43天时全氮、全钾、全磷、速效钾、有效磷与堆肥对照相比分别增加了19.51%、13.49%、6.07%、21.39%、9.03%。堆肥结束时各个处理发芽指数均达到80%以上,不会对植物造成毒害作用。整体来说,牛粪堆肥中添加0.2 mol/L的硫酸,堆肥效果最好。本研究为硫酸添加物应用于实际堆肥工程提供了理论依据。%In this study , to explore the effects of different concentrations of sulphuric acid on changes of pH and main nutrient elements during the windrow compost , an experiment of cattle manure composting was carried out for 43 days.Besides the control , three mixtures were treated with addition of different concentrations of sulphuric acid , 0.1 mol/L, 0.2 mol/L and 0.3 mol/L.The results show that during 43 days, the sulphuric acid addition treatments at 0.2 mol/L and 0.3 mol/L decrease the stage of initial high temperature , pH and carbon losses significantly, and increase the contents of total N , total K, total P, available potassium and available phosphorus effectively.The total N, total K, total P, available potassium and available phosphorus in the 0.2 mol/L sulphuric acid compost are increased by 19.51%, 13.49%, 6.07%, 21.39% and 9.03% respectively compared to the control in the 43 days.The germination index ( GI) value is over 80%at the

  16. Intellectual mobile Ad Hoc networks

    OpenAIRE

    Sova, Oleg; Romanjuk, Valeriy; Bunin, Sergey; Zhuk, Pavlo

    2012-01-01

    In this article intellectualization of Mobile Ad Hoc Networks resources management is offered. It was proposed decomposition of the primary goal of MANET functioning into easy subgoals, and fragment of the MANET node target structure is presented.

  17. Supergravity one-loop corrections on AdS7 and AdS3, higher spins and AdS/CFT

    Directory of Open Access Journals (Sweden)

    Matteo Beccaria

    2015-03-01

    Full Text Available As was shown earlier, the one-loop correction in 10d supergravity on AdS5×S5 corresponds to the contributions to the vacuum energy and 4d boundary conformal anomaly which are minus the values for one N=4 Maxwell supermultiplet, thus reproducing the subleading term in the N2−1 coefficient in the dual SU(N SYM theory. We perform similar one-loop computations in 11d supergravity on AdS7×S4 and 10d supergravity on AdS3×S3×T4. In the AdS7 case we find that the corrections to the 6d conformal anomaly a-coefficient and the vacuum energy are again minus the ones for one (2,0 tensor multiplet, suggesting that the total a-anomaly coefficient for the dual (2,0 theory is 4N3−9/4N−7/4 and thus vanishes for N=1. In the AdS3 case the one-loop correction to the vacuum energy or 2d central charge turns out to be equal to that of one free (4,4 scalar multiplet, i.e. is c=+6. This reproduces the subleading term in the central charge c=6(Q1Q5+1 of the dual 2d CFT describing decoupling limit of D5–D1 system. We also present the expressions for the 6d a-anomaly coefficient and vacuum energy contributions of general-symmetry higher spin field in AdS7 and consider their application to tests of vectorial AdS/CFT with the boundary conformal 6d theory represented by free scalars, spinors or rank-2 antisymmetric tensors.

  18. Entanglement Temperature and Perturbed AdS$_3$ Geometry

    CERN Document Server

    Levine, Gregory

    2015-01-01

    In analogy to the first law of thermodynamics, the increase in entanglement entropy $\\delta S$ of a conformal field theory (CFT) is proportional to the increase in energy, $\\delta E$, of the subsystem divided by an effective entanglement temperature, $T_E$. Extending this analogy, we study entanglement entropy when the subsystem is perturbed by applying an external field, expressed as a coupling to a local marginal operator in the CFT. We show that the resulting entropy change is associated with a change in the entanglement temperature itself, leading to an equation analogous to the Clausius relation. Using AdS/CFT duality we develop a relationship between a perturbation in the local entanglement temperature, $\\delta T_E(x)$ of the CFT and the perturbation of the bulk AdS metric. Using the AdS$_3$ minimal surface as a probe, we can construct bulk metric perturbations from an exact numerical computation of the entanglement temperature in a two dimensional $c=1$ boundary theory deformed by a marginal perturbati...

  19. Ultraviolet asymptotics and singular dynamics of AdS perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Craps, Ben [Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University, Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium); Vanhoof, Joris [Theoretische Natuurkunde, Vrije Universiteit Brussel, and The International Solvay Institutes, Pleinlaan 2, B-1050 Brussels (Belgium)

    2015-10-12

    Important insights into the dynamics of spherically symmetric AdS-scalar field perturbations can be obtained by considering a simplified time-averaged theory accurately describing perturbations of amplitude ε on time-scales of order 1/ε{sup 2}. The coefficients of the time-averaged equations are complicated expressions in terms of the AdS scalar field mode functions, which are in turn related to the Jacobi polynomials. We analyze the behavior of these coefficients for high frequency modes. The resulting asymptotics can be useful for understanding the properties of the finite-time singularity in solutions of the time-averaged theory recently reported in the literature. We highlight, in particular, the gauge dependence of this asymptotics, with respect to the two most commonly used gauges. The harsher growth of the coefficients at large frequencies in higher-dimensional AdS suggests strengthening of turbulent instabilities in higher dimensions. In the course of our derivations, we arrive at recursive relations for the coefficients of the time-averaged theory that are likely to be useful for evaluating them more efficiently in numerical simulations.

  20. Bioconversion technologies of crude glycerol to value added industrial products

    Directory of Open Access Journals (Sweden)

    Vijay Kumar Garlapati

    2016-03-01

    Full Text Available Crude glycerol that is produced as the by-product from biodiesel, has to be effectively utilized to contribute to the viability of biodiesel. Crude glycerol in large amounts can pose a threat to the environment. Therefore, there is a need to convert this crude glycerol into valued added products using biotechnological processes, which brings new revenue to biodiesel producers. Crude glycerol can serve as a feedstock for biopolymers, poly unsaturated fatty acids, ethanol, hydrogen and n-butanol production and as a raw material for different value added industrial products. Hence, in this review we have presented different bioconversion technologies of glycerol to value added industrial products.

  1. Coherent Cascade: Collapsing Solutions in Global AdS

    CERN Document Server

    Freivogel, Ben

    2015-01-01

    We analyze the gravitational dynamics of a classical scalar field that sometimes leads to blackhole formation in asymptotically AdS spacetime at the shortest nonlinear time scale. We present strong evidence that the dynamics is governed by a "coherent cascade", with all modes remaining in phase as the energy flows to higher frequencies into a power-law spectrum. Using a coherent phase ansatz, we analytically find these power-law solutions. We show how the particular power is determined by the scaling properties of the interaction coefficients. Our result agrees with existing numerical results in 4+1 dimensions, and makes predictions in higher dimensions.

  2. Configurational entropy of charged AdS black holes

    Science.gov (United States)

    Lee, Chong Oh

    2017-09-01

    When we consider charged AdS black holes in higher dimensional spacetime and a molecule number density along coexistence curves is numerically extended to higher dimensional cases. It is found that a number density difference of a small and large black holes decrease as a total dimension grows up. In particular, we find that a configurational entropy is a concave function of a reduced temperature and reaches a maximum value at a critical (second-order phase transition) point. Furthermore, the bigger a total dimension becomes, the more concave function in a configurational entropy while the more convex function in a reduced pressure.

  3. Internal Structure of Charged AdS Black Holes

    CERN Document Server

    Bhattacharjee, Srijit; Virmani, Amitabh

    2016-01-01

    When an electrically charged black hole is perturbed its inner horizon becomes a singularity, often referred to as the Poisson-Israel mass inflation singularity. Ori constructed a model of this phenomenon for asymptotically flat black holes, in which the metric can be determined explicitly in the mass inflation region. In this paper we implement the Ori model for charged AdS black holes. We find that the mass function inflates faster than the flat space case as the inner horizon is approached. Nevertheless, the mass inflation singularity is still a weak singularity: although spacetime curvature becomes infinite, tidal distortions remain finite on physical objects attempting to cross it.

  4. Duality invariance of s≥32 fermions in AdS

    Directory of Open Access Journals (Sweden)

    S. Deser

    2014-11-01

    Full Text Available We show that in D=4 AdS, s≥3/2 partially massless (PM fermions retain the duality invariances of their flat space massless counterparts. They have tuned ratios m2/M2≠0 that turn them into sums of effectively massless unconstrained helicity ±(s,⋯,32 excitations, shorn of the lowest (non-dual helicity ±12-rung and — more generally — of succeeding higher rung as well. Each helicity mode is separately duality invariant, like its flat space counterpart.

  5. Reentrant Phase Transitions in Rotating AdS Black Holes

    CERN Document Server

    Altamirano, Natacha; Mann, Robert B

    2013-01-01

    We study the thermodynamics of higher-dimensional singly spinning asymptotically AdS black holes in the canonical (fixed J) ensemble of extended phase space, where the cosmological constant is treated as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Along with the usual small/large black hole phase transition, we find a new phenomenon of reentrant phase transitions for all d>5 dimensions, in which a monotonic variation of the temperature yields two phase transitions from large to small and back to large black holes. This situation is similar to that seen in multicomponent liquids.

  6. Entanglement entropy and duality in AdS4

    Directory of Open Access Journals (Sweden)

    Ioannis Bakas

    2015-07-01

    Full Text Available Small variations of the entanglement entropy δS and the expectation value of the modular Hamiltonian δE are computed holographically for circular entangling curves in the boundary of AdS4, using gravitational perturbations with general boundary conditions in spherical coordinates. Agreement with the first law of thermodynamics, δS=δE, requires that the line element of the entangling curve remains constant. In this context, we also find a manifestation of electric–magnetic duality for the entanglement entropy and the corresponding modular Hamiltonian, following from the holographic energy–momentum/Cotton tensor duality.

  7. Most general AdS_3 boundary conditions

    CERN Document Server

    Grumiller, Daniel

    2016-01-01

    We consider the most general asymptotically anti-de Sitter boundary conditions in three-dimensional Einstein gravity with negative cosmological constant. The metric contains in total twelve independent functions, six of which are interpreted as chemical potentials (or non-normalizable fluctuations) and the other half as canonical boundary charges (or normalizable fluctuations). Their presence modifies the usual Fefferman-Graham expansion. The asymptotic symmetry algebra consists of two sl(2)_k current algebras, the levels of which are given by k=l/(4G_N), where l is the AdS radius and G_N the three-dimensional Newton constant.

  8. M-Theory solutions with AdS factors

    CERN Document Server

    Gauntlett, J P; Pakis, S; Waldram, D; Gauntlett, Jerome P.; Kim, Nakwoo; Pakis, Stathis; Waldram, Daniel

    2002-01-01

    Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of a n-dimensional anti-de Sitter (AdS) space, with n=2,3,4,5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.

  9. M-theory solutions with AdS factors

    Energy Technology Data Exchange (ETDEWEB)

    Gauntlett, Jerome P [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Kim, Nakwoo [Max-Planck-Institut fuer Gravitationsphysik, Albert-Einstein-Institut, Am Muehlenberg 1, D-14476 Golm (Germany); Pakis, Stathis [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom); Waldram, Daniel [Department of Physics, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)

    2002-08-07

    Solutions of D=7 maximal gauged supergravity are constructed with metrics that are a product of an n-dimensional anti-de Sitter (AdS) space, with n=2, 3, 4, 5, and certain Einstein manifolds. The gauge fields have the same form as in the recently constructed solutions describing the near-horizon limits of M5-branes wrapping supersymmetric cycles. The new solutions do not preserve any supersymmetry and can be uplifted to obtain new solutions of D=11 supergravity, which are warped and twisted products of the D=7 metric with a squashed four-sphere. Some aspects of the stability of the solutions are discussed.

  10. Heavy quark potential from deformed AdS5 models

    Science.gov (United States)

    Zhang, Zi-qiang; Hou, De-fu; Chen, Gang

    2017-04-01

    In this paper, we investigate the heavy quark potential in some holographic QCD models. The calculation relies on a modified renormalization scheme mentioned in a previous work of Albacete et al. After studying the heavy quark potential in Pirner-Galow model and Andreev-Zakharov model, we extend the discussion to a general deformed AdS5 case. It is shown that the obtained potential is negative definite for all quark-antiquark separations, differs from that using the usual renormalization scheme.

  11. AdS Chern-Simons Gravity induces Conformal Gravity

    CERN Document Server

    Aros, Rodrigo

    2013-01-01

    The leitmotif of this paper is the question of whether four- and higher even-dimensional Conformal Gravities do have a Chern-Simons pedigree. We show that Weyl gravity can be obtained as dimensional reduction of a five-dimensional Chern-Simons action for a suitable (gauged-fixed, tractor-like) five-dimensional AdS connection. The gauge-fixing and dimensional reduction program admits a readily generalization to higher dimensions for the case of certain conformal gravities obtained by contractions of the Weyl tensor.

  12. ESTABILIDAD DE ALMACENAMIENTO DE ENSILADOS BIOLÓGICOS A PARTIR DE RESIDUOS DE PESCADO INOCULADOS CON BACTERIAS ÁCIDO-LÁCTICAS STORAGE STABILITY OF BIOLOGICAL SILAGE FROM FISH REMAINS ADDED WITH LACTIC ACID BACTERIA CULTURE

    Directory of Open Access Journals (Sweden)

    Veloza Gómez Luis Carlos

    2009-04-01

    Full Text Available Se elaboraron cuatro muestras por triplicado de ensilados biológicos para alimentación animal a partir de residuos de pescado, utilizando melaza como fuente de carbohidratos para el crecimiento de cuatro cepas de bacterias ácido-lácticas (BAL aisladas de los mismos, sometidos a un tiempo de incubación de 72 horas y temperatura de 35 °C (±2 °C para acidificar el producto como método de conservación. A continuación los ensilados se almacenaron durante 180 días a temperatura ambiente para evaluar la estabilidad en anaquel, por medio de análisis químicos, composición química proximal, aminograma, recuentos microbiológicos y algunos de tipo organoléptico del producto terminado. Las cepas fueron eficientes en el proceso de fermentación, causando inhibición del crecimiento de microorganismos indeseables y aportando características organolépticas agradables. El ensilado elaborado con la cepa C14 provocó el descenso del pH en menos de 72 horas de incubación. Ninguno de los productos sufrió deterioro evidente durante el almacenamiento; presentaron porcentajes aceptables de proteína, grasa, cenizas, carbohidratos y aminoácidos, que hacen del producto una fuente utilizable en formulaciones de alimentos para animales.Four biological silages samples for animal feeding were made from fish remains in triplicate, using molasses like source of carbohydrate for the growth of four lactic acid bacteria (LAB strains isolated from those remains and incubated during 72 hours and temperature of 35°C (±2°C to acidify the product as preservation method. Then, the silages were storage for 180 days at room temperature to asses the shelf stability by conducting chemical, proximal chemical composition, amine assessment, microbiological counting and some sensory evaluation in final product. Bacteria cultures were efficient in fermentation process causing inhibition growth of undesirable bacteria and giving pleasant sensory characteristics. The

  13. Introducing ADS 2.0

    Science.gov (United States)

    Accomazzi, Alberto; Kurtz, M. J.; Henneken, E. A.; Grant, C. S.; Thompson, D.; Luker, J.; Chyla, R.; Murray, S. S.

    2014-01-01

    In the spring of 1993, the Smithsonian/NASA Astrophysics Data System (ADS) first launched its bibliographic search system. It was known then as the ADS Abstract Service, a component of the larger Astrophysics Data System effort which had developed an interoperable data system now seen as a precursor of the Virtual Observatory. As a result of the massive technological and sociological changes in the field of scholarly communication, the ADS is now completing the most ambitious technological upgrade in its twenty-year history. Code-named ADS 2.0, the new system features: an IT platform built on web and digital library standards; a new, extensible, industrial strength search engine; a public API with various access control capabilities; a set of applications supporting search, export, visualization, analysis; a collaborative, open source development model; and enhanced indexing of content which includes the full-text of astronomy and physics publications. The changes in the ADS platform affect all aspects of the system and its operations, including: the process through which data and metadata are harvested, curated and indexed; the interface and paradigm used for searching the database; and the follow-up analysis capabilities available to the users. This poster describes the choices behind the technical overhaul of the system, the technology stack used, and the opportunities which the upgrade is providing us with, namely gains in productivity and enhancements in our system capabilities.

  14. Rindler-AdS/CFT

    CERN Document Server

    Parikh, Maulik

    2012-01-01

    In anti-de Sitter space a highly accelerating observer perceives a Rindler horizon. The two Rindler wedges in AdS_{d+1} are holographically dual to an entangled conformal field theory that lives on two boundaries with geometry R x H_{d-1}. For AdS_3, the holographic duality is especially tractable, allowing quantum-gravitational aspects of Rindler horizons to be probed. We recover the thermodynamics of Rindler-AdS space directly from the boundary conformal field theory. We derive the temperature from the two-point function and obtain the Rindler entropy density precisely, including numerical factors, using the Cardy formula. We also probe the causal structure of the spacetime, and find from the behavior of the one-point function that the CFT "knows" when a source has fallen across the Rindler horizon. This is so even though, from the bulk point of view, there are no local signifiers of the presence of the horizon. Finally, we discuss an alternate foliation of Rindler-AdS which is dual to a CFT living in de Si...

  15. The CFT dual of AdS gravity with torsion

    CERN Document Server

    Klemm, Dietmar

    2007-01-01

    We consider the Mielke-Baekler model of three-dimensional AdS gravity with torsion, which has gravitational and translational Chern-Simons terms in addition to the usual Einstein-Hilbert action with cosmological constant. It is shown that the topological nature of the model leads to a finite Fefferman-Graham expansion. We derive the holographic stress tensor and the associated Ward identities and show that, due to the asymmetry of the left- and right-moving central charges, a Lorentz anomaly appears in the dual conformal field theory. Both the consistent and the covariant Weyl and Lorentz anomaly are determined, and the Wess-Zumino consistency conditions for the former are verified. Moreover we consider the most general solution with flat boundary geometry, which describes left-and right-moving gravitational waves on AdS_3 with torsion, and shew that in this case the holographic energy-momentum tensor is given by the wave profiles. The anomalous transformation laws of the wave profiles under diffeomorphisms p...

  16. AdS nonlinear instability: moving beyond spherical symmetry

    Science.gov (United States)

    Dias, Óscar J. C.; Santos, Jorge E.

    2016-12-01

    Anti-de Sitter (AdS) is conjectured to be nonlinear unstable to a weakly turbulent mechanism that develops a cascade towards high frequencies, leading to black hole formation (Dafermos and Holzegel 2006 Seminar at DAMTP (University of Cambridge) available at https://dpmms.cam.ac.uk/~md384/ADSinstability.pdf, Bizon and Rostworowski 2011 Phys. Rev. Lett. 107 031102). We give evidence that the gravitational sector of perturbations behaves differently from the scalar one studied by Bizon and Rostworowski. In contrast with Bizon and Rostworowski, we find that not all gravitational normal modes of AdS can be nonlinearly extended into periodic horizonless smooth solutions of the Einstein equation. In particular, we show that even seeds with a single normal mode can develop secular resonances, unlike the spherically symmetric scalar field collapse studied by Bizon and Rostworowski. Moreover, if the seed has two normal modes, more than one resonance can be generated at third order, unlike the spherical collapse of Bizon and Rostworowski. We also show that weak turbulent perturbative theory predicts the existence of direct and inverse cascades, with the former dominating the latter for equal energy two-mode seeds.

  17. AdS pure spinor superstring in constant backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Chandia, Osvaldo [Departamento de Ciencias, Facultad de Artes Liberales, Universidad Adolfo Ibáñez,Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez,Diagonal Las Torres 2640, Peñalolén, Santiago (Chile); Bevilaqua, L. Ibiapina [Escola de Ciências e Tecnologia, Universidade Federal do Rio Grande do Norte,Caixa Postal 1524, 59072-970, Natal, RN (Brazil); Vallilo, Brenno Carlini [Facultad de Ciencias Exactas, Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile)

    2014-06-05

    In this paper we study the pure spinor formulation of the superstring in AdS{sub 5}×S{sup 5} around point particle solutions of the classical equations of motion. As a particular example we quantize the pure spinor string in the BMN background.

  18. A special road to AdS vacua

    CERN Document Server

    Cassani, Davide; Marrani, Alessio; Morales, Jose F; Samtleben, Henning

    2010-01-01

    We apply the techniques of special Kaehler geometry to investigate AdS_4 vacua of general N=2 gauged supergravities underlying flux compactifications of type II theories. We formulate the scalar potential and its extremization conditions in terms of a triplet of prepotentials P_x and their special Kaehler covariant derivatives only, in a form that recalls the potential and the attractor equations of N=2 black holes. We propose a system of first order equations for the P_x which generalize the supersymmetry conditions and yield non-supersymmetric vacua. Special geometry allows us to recast these equations in algebraic form, and we find an infinite class of new N=0 and N=1 AdS_4 solutions, displaying a rich pattern of non-trivial charges associated with NSNS and RR fluxes. Finally, by explicit evaluation of the entropy function on the solutions, we derive a U-duality invariant expression for the cosmological constant and the central charges of the dual CFT's.

  19. AdS twistors for higher spin theory

    CERN Document Server

    Cederwall, M

    2004-01-01

    We construct spectra of supersymmetric higher spin theories in D=4, 5 and 7 from twistors describing massless (super-)particles on AdS spaces. A massless twistor transform is derived in a geometric way from classical kinematics. Relaxing the spin-shell constraints on twistor space gives an infinite tower of massless states of a ``higher spin particle'', generalising previous work of Bandos et al. This can generically be done in a number of ways, each defining the states of a distinct higher spin theory, and the method provides a systematic way of finding these. We reproduce known results in D=4, minimal supersymmetric 5- and 7-dimensional models, as well as supersymmetrisations of Vasiliev's Sp-models as special cases. In the latter models a dimensional enhancement takes place, meaning that the theory lives on a space of higher dimension than the original AdS space, and becomes a theory of doubletons. This talk was presented at the XIXth Max Born Symposium ``Fundamental Interactions and Twistor-Like Methods''...

  20. Enthalpy and the Mechanics of AdS Black Holes

    CERN Document Server

    Kastor, David; Traschen, Jennie

    2009-01-01

    We present geometric derivations of the Smarr formula for static AdS black holes and an expanded first law that includes variations in the cosmological constant. These two results are further related by a scaling argument based on Euler's theorem. The key new ingredient in the constructions is a two-form potential for the static Killing field. Surface integrals of the Killing potential determine the coefficient of the variation of the cosmological constant in the first law. This coefficient is proportional to a finite, effective volume for the region outside the AdS black hole horizon, which can also be interpreted as minus the volume excluded from a spatial slice by the black hole horizon. This effective volume also contributes to the Smarr formula. Since the cosmological constant is naturally thought of as a pressure, the new term in the first law has the form of effective volume times change in pressure that arises in the variation of the enthalpy in classical thermodynamics. This and related arguments sug...

  1. Quantum cat map dynamics on AdS$_2$

    CERN Document Server

    Axenides, Minos; Nicolis, Stam

    2016-01-01

    We present a toy model for the chaotic unitary scattering of single particle wave packets on the radial AdS$_2$ geometry of extremal BH horizons. Based on our recent work for the discretization of the AdS$_2$ space-time, which describes a finite and random geometry, by modular arithmetic, we investigate the validity of the eigenstate thermalization hypothesis (ETH), as well as that of the fast scrambling time bound conjecture (STB), for an observer with time evolution operator the quantum Arnol'd cat map (QACM). We find that the QACM, while possessing a linear spectrum, has eigenstates, which can be expressed in closed form, are found to be random and to satisfy the assumptions of the ETH.The implications are that the dynamics is described by a chaotic, unitary, single particle S-matrix, which completely delocalizes and randomizes initial gaussian wave packets . Applying results obtained by Dyson and Falk for the periods of the Arnol'd Cat Map(ACM),which are related to its mixing time, we also find that the t...

  2. Smooth Causal Patches for AdS Black Holes

    CERN Document Server

    Raju, Suvrat

    2016-01-01

    We review the paradox of low energy excitations about an AdS black hole. An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than $k T$ cannot create a significant excitation in a thermal system. When we carefully examine the position dependence of the boundary unitary operator that produces the excitation and the bulk observable necessary to detect the anomalously large effect, we find that they do not both fit in a single causal patch. This follows from a remarkable property of position space AdS correlators that we establish explicitly, and resolves the paradox in a generic state of the system, since no combination of observers can both create the excitation and observe its effect. As a special case of our analy...

  3. AdCell: Ad Allocation in Cellular Networks

    CERN Document Server

    Alaei, Saeed; Liaghat, Vahid; Pei, Dan; Saha, Barna

    2011-01-01

    With more than four billion usage of cellular phones worldwide, mobile advertising has become an attractive alternative to online advertisements. In this paper, we propose a new targeted advertising policy for Wireless Service Providers (WSPs) via SMS or MMS- namely {\\em AdCell}. In our model, a WSP charges the advertisers for showing their ads. Each advertiser has a valuation for specific types of customers in various times and locations and has a limit on the maximum available budget. Each query is in the form of time and location and is associated with one individual customer. In order to achieve a non-intrusive delivery, only a limited number of ads can be sent to each customer. Recently, new services have been introduced that offer location-based advertising over cellular network that fit in our model (e.g., ShopAlerts by AT&T) . We consider both online and offline version of the AdCell problem and develop approximation algorithms with constant competitive ratio. For the online version, we assume tha...

  4. Online Ad Slotting With Cancellations

    CERN Document Server

    Constantin, Florin; Muthukrishnan, S; Pal, Martin

    2008-01-01

    Many advertisers buy advertisements (ads) on the Internet or on traditional media and seek simple, online mechanisms to reserve ad slots in advance. Media publishers represent a vast and varying inventory, and they too seek automatic, online mechanisms for pricing and allocating such reservations. In this paper, we present and study a simple model for auctioning such ad slots in advance. Bidders arrive sequentially and report which slots they are interested in. The seller must decide immediately whether or not to grant a reservation. Our model allows a seller to accept reservations, but possibly cancel the allocations later and pay the bidder a cancellation compensation (bump payment). Our main result is an online mechanism to derive prices and bump payments that is efficient to implement. This mechanism has many desirable properties. It is individually rational; winners have an incentive to be honest and bidding one's true value dominates any lower bid. Our mechanism's efficiency is within a constant fractio...

  5. Adding momentum to supersymmetric geometries

    Energy Technology Data Exchange (ETDEWEB)

    Lunin, Oleg, E-mail: olunin@albany.edu [Department of Physics, University at Albany (SUNY), Albany, NY 12222 (United States); Mathur, Samir D., E-mail: mathur.16@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States); Turton, David, E-mail: turton.7@osu.edu [Department of Physics, Ohio State University, Columbus, OH 43210 (United States)

    2013-03-11

    We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a traveling wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T{sup 4}. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.

  6. Adding momentum to supersymmetric geometries

    CERN Document Server

    Lunin, Oleg; Turton, David

    2012-01-01

    We consider general supersymmetric solutions to minimal supergravity in six dimensions, trivially lifted to IIB supergravity. To any such solution we add a travelling-wave deformation involving the additional directions. The deformed solution is given in terms of a function which is harmonic in the background geometry. We also present a family of explicit examples describing microstates of the D1-D5 system on T^4. In the case where the background contains a large AdS region, the deformation is identified as corresponding to an action of a U(1) current of the D1-D5 orbifold CFT on a given state.

  7. Determination of endogenous concentration of γ-hydroxybutyric acid (GHB) in hair through an ad hoc GC-MS analysis: A study on a wide population and influence of gender and age.

    Science.gov (United States)

    Vaiano, Fabio; Serpelloni, Giovanni; Furlanetto, Sandra; Palumbo, Diego; Mari, Francesco; Fioravanti, Alessia; Bertol, Elisabetta

    2016-01-25

    γ-Hydroxybutyric acid (GHB) spread for recreational purposes or as "rape drug" represents a hard issue for forensic toxicologists due to its endogenous nature. It is clear that an actual and reliable discrimination between basal and exogenous levels is mandatory to achieve a correct evaluation of conscious/unconscious administration. This research aimed to study the GHB baseline in hair samples, collected from 150 volunteers, non-consumers of any drugs of abuse, in order to evaluate if a generic cut-off value could be accepted, also focusing on potential influences of gender and age. The analysis consisted of an overnight incubation with NaOH at 56 °C, liquid-liquid extraction with ethylacetate and trimethylsylil derivatization. Detection was carried out through gas chromatography-mass spectrometry in single ion monitoring (m/z 233, 234, 147 for GHB; m/z 239, 240 and 147 for GHB-d6). The endogenous amount in "blank" hair was estimated by the standard addition method. Concentration range was 0.279-2.839 ng/mg. In males, the average GHB levels were higher than in females (0.829 vs 0.596 ng/mg, respectively), especially in the first age category (50); in female, quite similar levels were registered throughout all the age categories (0.606 ng/mg, 50). Further study should be performed on GHB physiology in order to better understand these differences among ages and genders. Moreover, we demonstrated that for hair analysis a cut-off reference value is not strictly mandatory, underlining the great interpretative valence of segmental analysis.

  8. The Blocking Effect of Phenolic Acid on N—Nitrosomorholine Formation in vitro

    Institute of Scientific and Technical Information of China (English)

    LIPING; WANGHuai-Zhou; 等

    1994-01-01

    Phenolic acid(PAs) are widely found in many daily consumed vegetables and fruits.The inhibitory effects of PAs on N-nitrosomorpholine(NMOR)formation in vitro under simulated gastric juice condition were studied.The results showed that the inhibitory potncy of thirteen varieties of PAs differed greatly,which may be related to their chemical structures;the blockine rate(BR)of different kinds of PAs were as follows:caffeic acid,92.5%;tannic acid,90.0%;gallic acid,86.8%;sinapinic acid,86.2%;ferulic acid,81.1%;chlorogenic acid,69.4%;gentisic acid,69.2%;syringic acid,62.1%;protocatechuic acid,56.0%;p-coumaric acid,52.5%;vannilic acid,35.4%;moreover,p-hydroxybenzoic acid and m-coumaric acid had the least blocking effect or even slight catalyzing effect.The results also demonstrated that amounts of NMOR formed were negatively correlated with molar ratio of PAs to nitrite and that the optimum pH for inhibition was betwwen 2 and 3 .

  9. Value Added Products from Renewable Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Blum, Paul [Univ. of Nebraska, Lincoln, NE (United States)

    2014-07-31

    Cellulosic ethanol is an emerging biofuel that will make strong contributions to American domestic energy needs. In the US midwest the standard method for pretreatment of biomass uses hot acid to deconstruct lignocellulose. While other methods work, they are not in common use. Therefore it is necessary to work within this context to achieve process improvements and reductions in biofuel cost. Technology underlying this process could supplement and even replace commodity enzymes with engineered microbes to convert biomass-derived lignocellulose feedstocks into biofuels and valueadded chemicals. The approach that was used here was based on consolidated bioprocessing. Thermoacidophilic microbes belonging to the Domain Archaea were evaluated and modfied to promote deconvolution and saccharification of lignocellulose. Biomass pretreatment (hot acid) was combined with fermentation using an extremely thermoacidophilic microbial platform. The identity and fate of released sugars was controlled using metabolic blocks combined with added biochemical traits where needed. LC/MS analysis supported through the newly established Nebraska Bioenergy Facility provided general support for bioenergy researchers at the University of Nebraska. The primary project strategy was to use microbes that naturally flourish in hot acid (thermoacidophiles) with conventional biomass pretreatment that uses hot acid. The specific objectives were: to screen thermoacidophilic taxa for the ability to deconvolute lignocellulose and depolymerize associated carbohydrates; evaluate and respond to formation of “inhibitors” that arose during incubation of lignocellulose under heated acidic conditions; identify and engineer “sugar flux channeling and catabolic blocks” that redirect metabolic pathways to maximize sugar concentrations; expand the hydrolytic capacity of extremely thermoacidophilic microbes through the addition of deconvolution traits; and establish the Nebraska Bioenergy Facility (NBF

  10. Ad valorem versus unit taxes

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Sørensen, Allan

    2010-01-01

    a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...

  11. Added Value via SPI supplement

    Science.gov (United States)

    Supplement that indicates where to find the source data sets on the EPA system.This dataset is associated with the following publication:Bowden, J., K.D. Talgo, T. Spero , and C. Nolte. Assessing the Added Value of Dynamical Downscaling Using the Standardized Precipitation Index. ADVANCES IN METEOROLOGY. Hindawi Publishing Corporation, New York, NY, USA, 2016(8432064): 14 pages, (2016).

  12. Holographic properties in three-dimensional AdS soliton using $AdS_3/CFT_2$

    CERN Document Server

    Peng, Yan

    2016-01-01

    We study the holographic description of a superconductor by the $AdS_{3}/CFT_{2}$ correspondence. The system is constructed with a Maxwell field and a charged scalar field coupled in the (2+1)-dimensional AdS soliton background. With analytical methods, we obtain the exact expression for the critical chemical potential as $\\mu_{c} = 1 + \\sqrt{1+m^2}$, which has also been generalized to higher dimensions as $\\mu_c \\thickapprox a + \\sqrt{m^2-m_{BF}^2}$ in this work. Around the phase transition points, we find a correspondence between the value of the scalar field at the tip and the scalar operator at infinity. We also arrive at the classical second order phase transition threshold exponent $\\beta=\\frac{1}{2}$ as the same as the mean field theory near the critical chemical potential. As the condensation becomes heavier, we show surprisingly that superconducting phases exist only in a certain range of the chemical potential, which is very different from higher-dimensional cases. And for the small enough negative ...

  13. Brownian motion in AdS/CFT

    NARCIS (Netherlands)

    de Boer, J.; Hubeny, V.E.; Rangamani, M.; Shigemori, M.

    2009-01-01

    We study Brownian motion and the associated Langevin equation in AdS/CFT. The Brownian particle is realized in the bulk spacetime as a probe fundamental string in an asymptotically AdS black hole background, stretching between the AdS boundary and the horizon. The modes on the string are excited by

  14. Colliding waves on a string in AdS$_3$

    CERN Document Server

    Vegh, David

    2015-01-01

    This paper is concerned with the classical motion of a string in global AdS$_3$. The initially static string stretches between two antipodal points on the boundary circle. Both endpoints are perturbed which creates cusps at a steady rate. The cusps propagate towards the interior where they collide. The behavior of the string depends on the strength of forcing. Three qualitatively different phases can be distinguished: transparent, gray, and black. The transparent region is analogous to a standing wave. In the black phase, there is a horizon on the worldsheet and cusps never reach the other endpoint. The string keeps folding and its length grows linearly over time. In the gray phase, the string still grows linearly. However, cusps do cross to the other side. The transparent and gray regions are separated by a transition point where a logarithmic accumulation of cusps is numerically observed. A simple model reproduces the qualitative behavior of the string in the three phases.

  15. Bootstrapping Pure Quantum Gravity in AdS3

    CERN Document Server

    Bae, Jin-Beom; Lee, Sungjay

    2016-01-01

    The three-dimensional pure quantum gravity with negative cosmological constant is supposed to be dual to the extremal conformal field theory of central charge $c=24k$ in two dimensions. We employ the conformal bootstrap method to analyze the extremal CFTs, and find numerical evidence for the non-existence of the extremal CFTs for sufficiently large central charge ($k \\ge 20$). We also explore near-extremal CFTs, a small modification of extremal ones, and find similar evidence for their non-existence for large central charge. This indicates, under the assumption of holomorphic factorization, the pure gravity in the weakly curved AdS$_3$ do not exist as a consistent quantum theory.

  16. On jordanian deformations of AdS5 and supergravity

    Science.gov (United States)

    Hoare, Ben; van Tongeren, Stijn J.

    2016-10-01

    We consider various homogeneous Yang-Baxter deformations of the {{AdS}}5× {{{S}}}5 superstring that can be obtained from the η-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the η-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which implies that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which do correspond to supergravity solutions.

  17. On jordanian deformations of AdS_5 and supergravity

    CERN Document Server

    Hoare, Ben

    2016-01-01

    We consider various homogeneous Yang-Baxter deformations of the AdS_5 x S^5 superstring that can be obtained from the eta-deformed superstring and related models by singular boosts. The jordanian deformations we obtain in this way behave similarly to the eta-deformed model with regard to supergravity: T dualizing the classical sigma model it is possible to find corresponding solutions of supergravity, which, however, have dilatons that prevent T dualizing back. Hence the backgrounds of these jordanian deformations are not solutions of supergravity. Still, they do satisfy a set of recently found modified supergravity equations which should imply that the corresponding sigma models are scale invariant. The abelian models that we obtain by singular boosts do directly correspond to solutions of supergravity. In addition to our main results we consider contraction limits of our main example, which also do not correspond to supergravity solutions.

  18. Higher spins on AdS3 from the worldsheet

    Science.gov (United States)

    Ferreira, Kevin; Gaberdiel, Matthias R.; Jottar, Juan I.

    2017-07-01

    It was recently shown that the CFT dual of string theory on AdS3 × S3 × T 4, the symmetric orbifold of T 4, contains a closed higher spin subsector. Via holography, this makes precise the sense in which tensionless string theory on this background contains a Vasiliev higher spin theory. In this paper we study this phenomenon directly from the worldsheet. Using the WZW description of the background with pure NS-NS flux, we identify the states that make up the leading Regge trajectory and show that they fit into the even spin N=4 Vasiliev higher spin theory. We also show that these higher spin states do not become massless, except for the somewhat singular case of level k = 1 where the theory contains a stringy tower of massless higher spin fields coming from the long string sector.

  19. Thermodynamics of charged Lovelock: AdS black holes

    Science.gov (United States)

    Prasobh, C. B.; Suresh, Jishnu; Kuriakose, V. C.

    2016-04-01

    We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime.

  20. Jet physics from static charges in AdS space

    Science.gov (United States)

    Chien, Yang-Ting; Schwartz, Matthew D.; Simmons-Duffin, David; Stewart, Iain W.

    2012-02-01

    Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a “conformal gauge” which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain nonplanar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges’ imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.

  1. Jet Physics from Static Charges in AdS

    CERN Document Server

    Chien, Yang-Ting; Simmons-Duffin, David; Stewart, Iain W

    2011-01-01

    Soft interactions with high-energy jets are explored in radial coordinates which exploit the approximately conformal behavior of perturbative gauge theories. In these coordinates, the jets, approximated by Wilson lines, become static charges in Euclidean AdS. The anomalous dimension of the corresponding Wilson line operator is then determined by the potential energy of the charges. To study these Wilson lines we introduce a "conformal gauge" which does not have kinetic mixing between radial and angular directions, and show that a number of properties of Wilson lines are reproduced through relatively simple calculations. For example, certain non-planar graphs involving multiple Wilson lines automatically vanish. We also discuss the linear growth of the charges' imaginary potential energy with separation, and a relationship between Wilson line diagrams and Witten diagrams.

  2. An Investigation of AdS2 Backreaction and Holography

    CERN Document Server

    Engelsöy, Julius; Verlinde, Herman

    2016-01-01

    We investigate a dilaton gravity model in AdS2 proposed by Almheiri and Polchinski and develop an 1D effective description in terms of a dynamical boundary time with a Schwarzian derivative action. We show that the effective model is equivalent to a 1D version of Liouville theory, and investigate its dynamics and symmetries via a standard canonical framework. We include the coupling to arbitrary conformal matter and analyze the effective action in the presence of possible sources. We compute commutators of local operators at large time separation, and match the result with the time shift due to a gravitational shockwave interaction. We study a black hole evaporation process and comment on the role of entropy in this model.

  3. On Information Loss in AdS$_3$/CFT$_2$

    CERN Document Server

    Fitzpatrick, A Liam; Li, Daliang; Wang, Junpu

    2016-01-01

    We discuss information loss from black hole physics in AdS$_3$, focusing on two sharp signatures infecting CFT$_2$ correlators at large central charge $c$: 'forbidden singularities' arising from Euclidean-time periodicity due to the effective Hawking temperature, and late-time exponential decay in the Lorentzian region. We study an infinite class of examples where forbidden singularities can be resolved by non-perturbative effects at finite $c$, and we show that the resolution has certain universal features that also apply in the general case. Analytically continuing to the Lorentzian regime, we find that the non-perturbative effects that resolve forbidden singularities qualitatively change the behavior of correlators at times $t \\sim S_{BH}$, the black hole entropy. This may resolve the exponential decay of correlators at late times in black hole backgrounds. By Borel resumming the $1/c$ expansion of exact examples, we explicitly identify 'information-restoring' effects from heavy states that should correspo...

  4. Supersymmetry Properties of AdS Supergravity Backgrounds

    Science.gov (United States)

    Beck, Samuel; Gutowski, Jan; Papadopoulos, George

    2017-01-01

    Anti-de Sitter supergravity backgrounds are of particular interest in light of the AdS/CFT correspondence, which relates them to dual conformal field theories on the boundary of the anti-de Sitter space. We have investigated the forms of the supersymmetries these backgrounds preserve by solving the Killing spinor equations on the anti-de Sitter components of these spaces. We have found that a supersymmetric AdSn background necessarily preserves 2⌊n/2⌋ k supersymmetries for n 0 . Additionally, we have found that the Killing spinors of each background are exactly the zeroes of a Dirac-like operator constructed from the Killing spinor equations.

  5. Thermodynamics of charged Lovelock: AdS black holes

    Energy Technology Data Exchange (ETDEWEB)

    Prasobh, C.B.; Suresh, Jishnu; Kuriakose, V.C. [Cochin University of Science and Technology, Department of Physics, Cochin (India)

    2016-04-15

    We investigate the thermodynamic behavior of maximally symmetric charged, asymptotically AdS black hole solutions of Lovelock gravity. We explore the thermodynamic stability of such solutions by the ordinary method of calculating the specific heat of the black holes and investigating its divergences which signal second-order phase transitions between black hole states. We then utilize the methods of thermodynamic geometry of black hole spacetimes in order to explain the origin of these points of divergence. We calculate the curvature scalar corresponding to a Legendre-invariant thermodynamic metric of these spacetimes and find that the divergences in the black hole specific heat correspond to singularities in the thermodynamic phase space. We also calculate the area spectrum for large black holes in the model by applying the Bohr-Sommerfeld quantization to the adiabatic invariant calculated for the spacetime. (orig.)

  6. Adiabatic pumping solutions in global AdS

    Science.gov (United States)

    Carracedo, Pablo; Mas, Javier; Musso, Daniele; Serantes, Alexandre

    2017-05-01

    We construct a family of very simple stationary solutions to gravity coupled to a massless scalar field in global AdS. They involve a constantly rising source for the scalar field at the boundary and thereby we name them pumping solutions. We construct them numerically in D = 4. They are regular and, generically, have negative mass. We perform a study of linear and nonlinear stability and find both stable and unstable branches. In the latter case, solutions belonging to different sub-branches can either decay to black holes or to limiting cycles. This observation motivates the search for non-stationary exactly timeperiodic solutions which we actually construct. We clarify the role of pumping solutions in the context of quasistatic adiabatic quenches. In D = 3 the pumping solutions can be related to other previously known solutions, like magnetic or translationally-breaking backgrounds. From this we derive an analytic expression.

  7. Worldsheet dilatation operator for the AdS superstring

    Energy Technology Data Exchange (ETDEWEB)

    Ramírez, Israel [Departamento de Física, Universidad Técnica Federico Santa María,Casilla 110-V, Valparaíso (Chile); Institut für Mathematik und Institut für Physik, Humboldt-Universität zu Berlin,IRIS Haus, Zum Großen Windkanal 6, 12489 Berlin (Germany); Vallilo, Brenno Carlini [Departamento de Ciencias Físicas, Universidad Andres Bello,Republica 220, Santiago (Chile)

    2016-05-23

    In this work we propose a systematic way to compute the logarithmic divergences of composite operators in the pure spinor description of the AdS{sub 5}×S{sup 5} superstring. The computations of these divergences can be summarized in terms of a dilatation operator acting on the local operators. We check our results with some important composite operators of the formalism.

  8. Islands of stability and recurrence times in AdS

    CERN Document Server

    Green, Stephen R; Lehner, Luis; Liebling, Steven L

    2015-01-01

    We study the stability of anti-de Sitter (AdS) spacetime to spherically symmetric perturbations of a real scalar field in general relativity. Further, we work within the context of the "two time framework" (TTF) approximation, which describes the leading nonlinear effects for small amplitude perturbations, and is therefore suitable for studying the weakly turbulent instability of AdS---including both collapsing and non-collapsing solutions. We have previously identified a class of quasi-periodic (QP) solutions to the TTF equations, and in this work we analyze their stability. We show that there exist several families of QP solutions that are stable to linear order, and we argue that these solutions represent islands of stability in TTF. We extract the eigenmodes of small oscillations about QP solutions, and we use them to predict approximate recurrence times for generic non-collapsing initial data in the full (non-TTF) system. Alternatively, when sufficient energy is driven to high-frequency modes, as occurs ...

  9. Holographic reconstruction of AdS exchanges from crossing symmetry

    Science.gov (United States)

    Alday, Luis F.; Bissi, Agnese; Perlmutter, Eric

    2017-08-01

    Motivated by AdS/CFT, we address the following outstanding question in large N conformal field theory: given the appearance of a single-trace operator in the O× O OPE of a scalar primary O , what is its total contribution to the vacuum four-point function theories at leading order in 1/ N. Viewed holographically, this provides a field theory reconstruction of crossing-symmetric, four-point exchange amplitudes in AdS5. Our solution takes the form of a resummation of the large spin solution to the crossing equations, supplemented by corrections at finite spin, required by crossing. The method can be applied to the exchange of operators of arbitrary twist τ and spin s, although it vastly simplifies for even-integer twist, where we give explicit results. The output is the set of OPE data for the exchange of all double-trace operators {[OO]}_{n,ℓ } . We find that the double-trace anomalous dimensions γ n, ℓ are negative, monotonic and convex functions of ℓ, for all n and all ℓ > s. This constitutes a holographic signature of bulk causality and classical dynamics of even-spin fields. We also find that the "derivative relation" between double-trace anomalous dimensions and OPE coefficients does not hold in general, and derive the explicit form of the deviation in several cases. Finally, we study large n limits of γ n,ℓ, relevant for the Regge and bulk-point regimes.

  10. AdS/CFT Duality User Guide

    CERN Document Server

    Natsuume, Makoto

    2014-01-01

    This is the draft version of a textbook on "real-world" applications of the AdS/CFT duality for beginning graduate students in particle physics and for researchers in the other fields. The aim of this book is to provide background materials such as string theory, general relativity, nuclear physics, nonequilibrium physics, and condensed-matter physics as well as some key applications of the AdS/CFT duality in a single textbook. Contents: (1) Introduction, (2) General relativity and black holes, (3) Black holes and thermodynamics, (4) Strong interaction and gauge theories, (5) The road to AdS/CFT, (6) The AdS spacetime, (7) AdS/CFT - equilibrium, (8) AdS/CFT - adding probes, (9) Basics of nonequilibrium physics, (10) AdS/CFT - nonequilibrium, (11) Other AdS spacetimes, (12) Applications to quark-gluon plasma, (13) Basics of phase transition, (14) AdS/CFT - phase transition.

  11. Facilities Management and Added Value

    DEFF Research Database (Denmark)

    Jensen, Per Anker

    2010-01-01

    Aim: This paper aims to present different models of the concept of the added value of Facilities Management (FM), including the FM Value Map, which forms the basis of research group in EuroFM, and to present some of the results of this research collaboration. Approach and methodology: The paper...... on the aimed output) and the internal resource based view (with a focus on the input from FM and RE). Good relationship management and building on trust shows to be equally important as delivering the agreed services. In order to measure the multi-dimensional components of adding value both qualitative...... is based on literature reviews of the most influential journals within the academic fields of FM, Corporate Real Estate Management and Business to Business Marketing and discussions between participants of the research group working on a further exploration and testing of the FM Value Map. Conclusions...

  12. The PredictAD project

    DEFF Research Database (Denmark)

    Antila, Kari; Lötjönen, Jyrki; Thurfjell, Lennart;

    2013-01-01

    can be managed. Today the significance of early and precise diagnosis of AD is emphasized in order to minimize its irreversible effects on the nervous system. When new drugs and therapies enter the market it is also vital to effectively identify the right candidates to benefit from these. The main...... candidates and implement the framework in software. The results are currently used in several research projects, licensed to commercial use and being tested for clinical use in several trials....

  13. Scattering States in AdS/CFT

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, A.Liam; /Boston U.; Kaplan, Jared; /SLAC

    2012-02-14

    We show that suitably regulated multi-trace primary states in large N CFTs behave like 'in' and 'out' scattering states in the flat-space limit of AdS. Their transition matrix elements approach the exact scattering amplitudes for the bulk theory, providing a natural CFT definition of the flat space S-Matrix. We study corrections resulting from the AdS curvature and particle propagation far from the center of AdS, and show that AdS simply provides an IR regulator that disappears in the flat space limit.

  14. Holography in 3D AdS gravity with torsion

    CERN Document Server

    Blagojević, Milutin; Miskovic, Olivera; Olea, Rodrigo

    2013-01-01

    Basic aspects of the AdS/CFT correspondence are studied in the framework of 3-dimensional gravity with torsion. After choosing a consistent holographic ansatz, we formulate an improved approach to the Noether--Ward identities for the boundary theory. The method is applied first to the topological Mielke--Baekler model, and then to the more interesting (parity-preserving) 3-dimensional gravity with propagating torsion. In both cases, we find the finite holographic energy-momentum and spin currents and obtain the associated (anomalous) Noether--Ward identities.

  15. Towards Timelike Singularity via AdS Dual

    CERN Document Server

    Bhowmick, Samrat

    2016-01-01

    It is well known that Kasner geometry with spacelike singularity can be extended to bulk AdS-like geometry, furthermore one can study field theory on this Kasner space via its gravity dual. In this paper, we show that there exists a Kasner-like geometry with timelike singularity for which one can construct a dual gravity description. We then study various minimal surfaces including spacelike geodesics. Finally, we compute correlators of highly massive operators in the boundary field theory with a geodesic approximation.

  16. Canonical energy and hairy AdS black holes

    CERN Document Server

    Hyun, Seungjoon; Yi, Sang-Heon

    2016-01-01

    We propose the modified version of the canonical energy which was introduced originally by Hollands and Wald. Our construction depends only on the Euler-Lagrange expression of the system and thus is independent of the ambiguity in the Lagrangian. After some comments on our construction, we briefly mention on the relevance of our construction to the boundary information metric in the context of the AdS/CFT correspondence. We also study the stability of three-dimensional hairy extremal black holes by using our construction.

  17. 27 CFR 24.182 - Use of acid to correct natural deficiencies.

    Science.gov (United States)

    2010-04-01

    ... citric acid may be added to citrus fruit, juice or wine, only malic acid may be added to apples, apple juice or wine, and only citric acid or malic acid may be added to other fruit (including berries) or to... citric acid for other fruit (including berries). (d) Other use of acid. A winemaker desiring to use...

  18. Presence of non-fibrillar amyloid beta protein in skin biopsies of Alzheimer's disease (AD), Down's syndrome and non-AD normal persons

    DEFF Research Database (Denmark)

    Wen, G Y; Wisniewski, H M; Blondal, H

    1994-01-01

    A total of 66 skin biopsies from persons with Alzheimer's disease (AD) or Down's syndrome (DS) and from persons without AD were used in this study. The age range was from 7 to 89 years. Positive immunoreactivity of skin biopsies to monoclonal antibody 4G8, which is reactive to amino acid residue 17...

  19. Stability of Charged Global AdS$_4$ Spacetimes

    CERN Document Server

    Arias, Raúl; Serantes, Alexandre

    2016-01-01

    We study linear and nonlinear stability of asymptotically AdS$_4$ solutions in Einstein-Maxwell-scalar theory. After summarizing the set of static solutions we first examine thermodynamical stability in the grand canonical ensemble and the phase transitions that occur among them. In the second part of the paper we focus on nonlinear stability in the microcanonical ensemble by evolving radial perturbations numerically. We find hints of an instability corner for vanishingly small perturbations of the same kind as the ones present in the uncharged case. Collapses are avoided, instead, if the charge and mass of the perturbations come to close the line of solitons. Finally we examine the soliton solutions. The linear spectrum of normal modes is not resonant and instability turns on at extrema of the mass curve. Linear stability extends to nonlinear stability up to some threshold for the amplitude of the perturbation. Beyond that, the soliton is destroyed and collapses to a hairy black hole. The relative width of t...

  20. AdS crunches, CFT falls, and cosmological complexity

    CERN Document Server

    Barbón, José Luis

    2015-01-01

    This chapter discusses the holographic description of crunching AdS cosmologies. Crunching FRW models with hyperbolic spatial sections are dual to semiclassical condensates in deformed de Sitter (dS) CFTs. dS-invariant condensates with a sharply defined energy scale are induced by effective negative-definite relevant or marginal operators, which may or may not destabilize the CFT. This result is obtained by explicitly constructing a “complementarity map” for this model, given by a conformal transformation of the dS CFT into a static time-frame, which reveals the crunch as an infinite potential-energy fall in finite time. Quite generically, the crunch is associated with a finite-mass black hole if the dS O(d, 1) invariance is an accidental IR symmetry, broken to U(1) × O(d) in the UV. Any such regularization cuts off the eternity of dS spacetime. Equivalently, the dimension of the Hilbert space propagating into the crunch is finite only when dS is not eternal.

  1. F-theory and AdS3/CFT2

    Science.gov (United States)

    Couzens, Christopher; Lawrie, Craig; Martelli, Dario; Schäfer-Nameki, Sakura; Wong, Jin-Mann

    2017-08-01

    We construct supersymmetric AdS3 solutions in F-theory, that is Type IIB supergravity with varying axio-dilaton, which are holographically dual to 2d N=(0,4) superconformal field theories with small superconformal algebra. In F-theory these arise from D3-branes wrapped on curves in the base of an elliptically fibered Calabi-Yau threefold Y 3 and correspond to self-dual strings in the 6d N=(1,0) theory obtained from F-theory on Y 3. The non-trivial fibration over the wrapped curves implies a varying coupling of the N=4 Super-Yang-Mills theory on the D3-branes. We compute the holographic central charges and show that these agree with the field theory and with the anomalies of self-dual strings in 6d. We complement our analysis with a discussion of the dual M-theory solutions and a comparison of the central charges.

  2. On modular properties of the AdS3 CFT

    CERN Document Server

    Baron, Walter

    2010-01-01

    We study modular properties of the AdS3 WZNW model. Although the Euclidean partition function is modular invariant, the characters on the Euclidean torus are ill-defined and their modular transformations are unknown. We reconsider the characters defined on the Lorentzian torus, focusing on their structure as distributions. We find a generalized S matrix, depending on the sign of the real modular parameters, which has two diagonal blocks and one off-diagonal block, mixing discrete and continuous representations, that we fully determine. We then explore the relations among the modular transformations, the fusion algebra and the boundary states. We explicitly construct Ishibashi states for the maximally symmetric D-branes and show that the generalized S matrix defines the one-point functions associated to point-like and H2 branes as well as the fusion rules of the degenerate representations of SL(2,R) appearing in the open string spectrum of the point-like D-branes, through a generalized Verlinde theorem.

  3. The ADS All Sky Survey

    Science.gov (United States)

    Goodman, Alyssa

    We will create the first interactive sky map of astronomers' understanding of the Universe over time. We will accomplish this goal by turning the NASA Astrophysics Data System (ADS), widely known for its unrivaled value as a literature resource, into a data resource. GIS and GPS systems have made it commonplace to see and explore information about goings-on on Earth in the context of maps and timelines. Our proposal shows an example of a program that lets a user explore which countries have been mentioned in the New York Times, on what dates, and in what kinds of articles. By analogy, the goal of our project is to enable this kind of exploration-on the sky-for the full corpus of astrophysical literature available through ADS. Our group's expertise and collaborations uniquely position us to create this interactive sky map of the literature, which we call the "ADS All-Sky Survey." To create this survey, here are the principal steps we need to follow. First, by analogy to "geotagging," we will "astrotag," the ADS literature. Many "astrotags" effectively already exist, thanks to curation efforts at both CDS and NED. These efforts have created links to "source" positions on the sky associated with each of the millions of articles in the ADS. Our collaboration with ADS and CDS will let us automatically extract astrotags for all existing and future ADS holdings. The new ADS Labs, which our group helps to develop, includes the ability for researchers to filter article search results using a variety of "facets" (e.g. sources, keywords, authors, observatories, etc.). Using only extracted astrotags and facets, we can create functionality like what is described in the Times example above: we can offer a map of the density of positions' "mentions" on the sky, filterable by the properties of those mentions. Using this map, researchers will be able to interactively, visually, discover what regions have been studied for what reasons, at what times, and by whom. Second, where

  4. Noncommutative AdS2/CFT1 duality: The case of massless scalar fields

    Science.gov (United States)

    Pinzul, A.; Stern, A.

    2017-09-01

    We show how to construct correlators for the CFT1 which is dual to noncommutative AdS2 (n c AdS2). We do it explicitly for the example of the massless scalar field on Euclidean n c AdS2. n c AdS2 is the quantization of AdS2 that preserves all the isometries. It is described in terms of the unitary irreducible representations, more specifically discrete series representations, of s o (2 ,1 ). We write down symmetric differential representations for the discrete series and then map them to functions on the Moyal-Weyl plane. The Moyal-Weyl plane has a large distance limit which can be identified with the boundary of n c AdS2. Killing vectors can be constructed on n c AdS2 which reduce to the AdS2 Killing vectors near the boundary. We, therefore, conclude that n c AdS2 is asymptotically AdS2, and so the AdS /CFT correspondence should apply. For the example of the massless scalar field on Euclidean n c AdS2, the on-shell action, and resulting two-point function for the boundary theory, are computed to leading order in the noncommutativity parameter. The computation is nontrivial because nonlocal interactions appear in the Moyal-Weyl description. Nevertheless, the result is remarkably simple and agrees with that of the commutative scalar field theory, up to a rescaling.

  5. A study of the IR spectra of the copigments of malvin chloride with organic acids

    Directory of Open Access Journals (Sweden)

    ZORAN P. NEDIC

    2001-07-01

    Full Text Available The infrared spectra of the copigments of malvin with several organic acids: caffeic, ferulic, sinapic, chlorogenic, and tannic, were analyzed in order to elucidate the bonding of the molecules in the copigments. It was established that copigmentation is realized through hydrogen bonding between malvin molecules and the acids under study. The infrared spectra reveal that two groups of hydrogen bonds are formed, which include interactions of different molecular structures: hydroxy groups (bands around 3500 cm–1 and oxonium ions of the molecules (bands below 3000 cm–1. The formed hydrogen bonds were found to be of different strengths. The strengths of the hydrogen bonds were tentatively correlated with thermodynamic properties of the corresponding copigmentation reactions.

  6. [Enantioseparation behavior of chiral stationary phases AD, AS and OD].

    Science.gov (United States)

    Li, Liqun; Fan, Jun; Zhang, Jing; Chen, Xiaodong; Wang, Tai; He, Jianfeng; Zhang, Weiguang

    2016-01-01

    Over the past decades, HPLC enantioseparation with chiral stationary phases (CSPs) has been widely applied in chiral analysis and preparation of new pharmaceuticals, pesticides, food, etc. Herein, enantioseparation of 20 chiral compounds have been carried out on three polysaccharide-based CSPs (EnantioPak AD, AS and OD) with normal phases by HPLC, separately. The influences of skeletal structure and the kinds of derivative groups on separation behaviors of these CSPs have been studied in detail. As results indicated, except for compound 13, the other compounds were baseline separated on EnantioPak AD, with most of resolution over 2. 0; in addition, better separation for acidic or basic compounds was achieved through adding acidic/basic additives into the mobile phase of hexane-alcohol. For four aromatic alcohols (compounds 13-16), their retention in the EnantioPak AD column showed a weakening tendency with increase of carbon number in side chain group, and the reverse trend of their resolution was observed. Furthermore, EnantioPak AD showed much better separation performance for eight compounds (13-20) than the others. In short, these results have provided some references for further investigation of separation behavior and applications of polysaccharide-based CSPs.

  7. ACYLATION OF ACTIVATED AROMATICS WITHOUT ADDED ACID CATALYST. (R828130)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  8. Entanglement Entropy of AdS Black Holes

    Directory of Open Access Journals (Sweden)

    Maurizio Melis

    2010-11-01

    Full Text Available We review recent progress in understanding the entanglement entropy of gravitational configurations for anti-de Sitter gravity in two and three spacetime dimensions using the AdS/CFT correspondence. We derive simple expressions for the entanglement entropy of two- and three-dimensional black holes. In both cases, the leading term of the entanglement entropy in the large black hole mass expansion reproduces exactly the Bekenstein-Hawking entropy, whereas the subleading term behaves logarithmically. In particular, for the BTZ black hole the leading term of the entanglement entropy can be obtained from the large temperature expansion of the partition function of a broad class of 2D CFTs on the torus.

  9. Salivary protein levels as a predictor of perceived astringency in model systems and solid foods.

    Science.gov (United States)

    Fleming, Erin E; Ziegler, Gregory R; Hayes, John E

    2016-09-01

    Salivary protein difference value (SP D-value) is a quantitative measure of salivary protein replenishment, which reportedly relates to individual differences in perceived astringency. This in vitro measure is calculated as the difference in total salivary protein before (S1) and after (S2) stimulation with tannic acid, with a greater absolute value (S2-S1) indicating less protein replenishment. Others report that this measure predicts perceived astringency and liking of liquid model systems and beverages containing added polyphenols. Whether this relationship generalizes to astringent compounds other than polyphenols, or to solid foods is unknown. Here, the associations between SP D-values and perceived astringency and overall liking/disliking for alum and tannic acid (experiment 1) as well as solid chocolate-flavored compound coating with added tannic acid or grape seed extract (GSE) (experiment 2) were examined. In both experiments, participants (n=84 and 81, respectively) indicated perceived intensity of astringency, bitterness, sweetness, and sourness, and degree of liking of either aqueous solutions, or solid chocolate-flavored compound coating with added astringents. Data were analyzed via linear regression, and as discrete groups for comparison to prior work. Three discrete groups were formed based on first and third quartile splits of the SP D-value distribution: low (LR), medium (MR), and high responding (HR) individuals. In experiment 1, significantly higher mean astringency ratings were observed for the HR as compared to the LR/MR groups for alum and tannic acid, confirming and extending prior work. In experiment 2, significantly higher mean astringency ratings were also observed for HR as compared to LR groups in solid chocolate-flavored compound containing added tannic acid or GSE. Significant differences in liking were found between HR and LR groups for alum and tannic acid in water, but no significant differences in liking were observed for

  10. Determination of acetylsalicylic acid and salicylic acid in foods, using HPLC with fluorescence detection.

    OpenAIRE

    Venema, D.P.; Hollman, P.C.H.; Janssen, P.L.T.M.K.; Katan, M B

    1996-01-01

    We developed a specific and sensitive HPLC method with fluorescence detection for the determination of free acetylsalicylic acid, free salicylic acid, and free salicylic acid plus salicylic acid after alkaline hydrolysis (free-plus-bound) in foods. Acetylsalicylic acid was detected after postcolumn hydrolysis to salicylic acid. With the method for free acetylsalicylic acid and salicylic acid, recovery was 95-98␏or acetylsalicylic acid added to foods and 92-102␏or salicylic acid. Recovery of a...

  11. MUSICAL ARRANGEMENT OF MEDIA ADS

    Directory of Open Access Journals (Sweden)

    Chernyshov Alexander V.

    2015-01-01

    Full Text Available The music-compositional principles of commercial and political advertising and also the self-promotion of electronic media (radio, television, Internet are considered in this mediatext: from the elementary beeps, symbolic functions, emblems/logos and musical brands to the sound engineering technology to underscore the product's name and the complex synthesis between music and intra movements and color-light design of frames. Simultaneously examines, how the musical arrangement of ethereal advertising is involved in creation the emotional drama or bravado which reach the level of explicit or associative counterpoint 'music with the advertised object or subject' and which extend to expression of cultural image of all the broadcast channel. The article explores the works of the next genres like infomercial, teleshopping, film-ad, and autonomous commercials that have been produced in European countries or USA.

  12. Ad valorem versus unit taxes

    DEFF Research Database (Denmark)

    Schröder, Philipp J.H.; Sørensen, Allan

    2010-01-01

    Real-world industries are composed from heterogeneous firms and substantial intra-industry reallocations take place, i.e. high productivity firms squeeze out low productivity firms. Previous tax-tool comparisons have not included these central forces of industry structure. This paper examines...... a general equilibrium monopolistic competition model with heterogeneous firms and intra-industry reallocations. We show that the welfare superiority of ad valorem over unit taxes under imperfect competition is not only preserved but amplified. The additional difference between the tools arises because unit...... taxes distort relative prices, which in turn reduces average industry productivity through reallocations (the survival and increased market share of lower productivity firms). Importantly, numerical solutions of the model reveal that the relative welfare loss from using the unit tax increases...

  13. Adding timing to the VELO

    CERN Document Server

    Mitreska, Biljana

    2017-01-01

    The LHCb experiment is designed to perform high precision measurements of matter-antimatter asymmetries and searches for rare and forbidden decays, with the aim of discovering new and unexpected particles and forces. In 2030 the LHC beam intensity will increase by a factor of 50 compared to current operations. This means increased samples of the particles we need to study, but it also presents experimental challenges. In particular, with current technology it becomes impossible to differentiate the many (>50) separate proton-proton collisions which occur for each bunch crossing.\\\\ In this project a Monte Carlo simulation was developed to model the operation of a silicon pixel vertex detector surrounding the collision region at LHCb, under the conditions expected after 2030, after the second upgrade of the Vertex Locator(VELO).The main goal was studying the effect of adding '4D' detectors which save high-precision timing information, in addition to the usual three spatial coordinates, as charged particles pas...

  14. 超高效液相色谱法检测西红花中非法添加的染料金橙Ⅱ%QualitatiVe and Quantitative Determinaion of Illegally Added Acid Orange Ⅱ in Croci Stigma by UPLC

    Institute of Scientific and Technical Information of China (English)

    胡晓炜

    2011-01-01

    目的 建立检测中药西红花中非法添加的金橙Ⅱ的液质联用鉴别法和超高效液相色谱含量测定法.方法 用超高效液相色谱法分离中药西红花中非法添加的金橙Ⅱ,用离子阱进行定性鉴别,流动相为乙腈-0.01 mol/L醋酸铵溶液(30:70),离子化模式为ESI(+),碰撞能量为30 V;用超高效液相色谱法测定金橙Ⅱ含量,流动相为乙腈-0.0l mol/L醋酸铵溶液(30:70),检测波长484 nm.结果 在拟订的质谱条件下,金橙Ⅱ产生[M+H-Na]+分子离子峰,二级质谱的特征碎片离子明显;定量检测方面,进样量与峰面积的线性范围为5.435~745.0 ng,r=0.999 0,平均加样回收率为98.29%,RSD为1.25%(n=5).结论 液质联用法定性准确、可靠,液相色谱含量测定法简便、快速、准确.%Objective To establish an identification method of LC -MS/MS and a quantification method of ultra performance liquid chromatography - mass spectrometry(UPLC - MS/MS) for determining illegally added acid orange Ⅱin Croci Stigma. Methods Illegally added acid orange Ⅱ in Croci Stigma was separated by UPLC and the qualitative identification was performed by ion trap. The mobile phase was consisted of acetonitrile -0. 01 mol/L ammonium acetate (30 ∶ 70). The ionization mode was ESI(+ ) and MS/MS collision energy was 30 V. Then, the content of acid orange Ⅱwas determined by UPLC with the mobile phase of acetonitrile -O.Olmol/L ammomum acetate (30 ∶70) and the detection wavelength was 484 nm. Results Under the experimental condition of mass spectrum. acid orange Ⅱ produced the [M+H - Na] + molecular ion peaks and apparently revealed the characteristic fragment ion of second order mass spectrum. In the quantitative determination, the linearity between the sample size and the peak area was over the range of 5. 435 -745. 0 ng, r=0. 999 0. The average recovery rate was 98. 29% , RSD was 1. 25% ( n =5). Conclusion The LC -MS/MS method is accurate and fast for the

  15. Stringy Membranes in AdS/CFT

    CERN Document Server

    Axenides, Minos; Linardopoulos, Georgios

    2013-01-01

    We study membrane configurations in AdS_{7/4}xS^{4/7}. The membranes are wrapped around the compact manifold S^{4/7} and are dynamically equivalent to bosonic strings in AdS_5. We thus conveniently identify them as "stringy membranes". For the case of AdS_7xS^4, their construction is carried out by embedding the Polyakov action for classical bosonic strings in AdS_5, into the corresponding membrane action. Therefore, every string configuration in AdS_5 can be realized by an appropriately chosen stringy membrane in AdS_7xS^4. We discuss the possibility of this being also the case for stringy membranes in AdS_4xS^7/Z^k (k > 1 or k = 1). By performing a stability analysis to the constructed solutions, we find that the (membrane) fluctuations along their transverse directions are organized in multiple Lam\\'{e} stability bands and gaps in the space of parameters of the configurations. In this membrane picture, strings exhibit a single band/gap structure. Since the spectrum of quadratic fluctuations is important fo...

  16. Spiky strings in AdS_3 x S^1 and their AdS-pp-wave limits

    CERN Document Server

    Ishizeki, R; Tirziu, A; Tseytlin, A A

    2008-01-01

    We study a class of classical solutions for closed strings moving in AdS_3 x S^1 part of AdS_5 x S^5 with energy E and spin S in AdS_3 and angular momentum J and winding m in S^1. They have rigid shape with n spikes in AdS_3. We find that when J or m are non-zero, the spikes do not end in cusps. We consider in detail a special large n limit in which S ~ n^2, J ~ n, i.e. S >> J >> 1, with (E+S)/ n^2, (E-S)/ n, J/n, m/n staying finite. In that limit the spiky spinning string approaches the boundary of AdS_5. We show that the corresponding solution can be interpreted as describing a periodic-spike string moving in AdS_3 --pp-wave x S^1 background. The resulting expression for the string energy should represent a strong-coupling prediction for anomalous dimension of a class of dual gauge theory states in a particular thermodynamic limit of the SL(2) spin chain.

  17. Recurring Anomaly Detection System (ReADS)

    Data.gov (United States)

    National Aeronautics and Space Administration — Overview: ReADS can analyze text reports, such as aviation reports and problem or maintenance records. ReADS uses text clustering algorithms to group loosely related...

  18. TV Snack Ads Make Preschoolers Snack More

    Science.gov (United States)

    ... Sesame Street" interrupted by TV ads for a salty snack food ended up eating more of that ... watched the show with commercials for a popular salty snack. The ads depicted kids happily playing and ...

  19. The AdS/CFT/Unparticle Correspondence

    CERN Document Server

    Cacciapaglia, Giacomo; Terning, John

    2009-01-01

    We examine the correspondence between the anti-de Sitter (AdS) description of conformal field theories (CFTs) and the unparticle description of CFTs. We show how unparticle actions are equivalent to holographic boundary actions for fields in AdS, and how massive unparticles provide a new type of infrared cutoff that can be simply implemented in AdS by a soft breaking of conformal symmetry. We also show that processes involving scalar unparticles with dimensions d_s<2 or fermion unparticles with dimensions d_f<5/2 are insensitive to ultraviolet cutoff effects. Finally we show that gauge interactions for unparticles can be described by bulk gauge interactions in AdS and that they correspond to minimal gauging of the non-local effective action, and we compute the fermion unparticle production cross-section.

  20. TASI lectures on AdS/CFT

    CERN Document Server

    Penedones, Joao

    2017-01-01

    We introduce the AdS/CFT correspondence as a natural extension of QFT in a fixed AdS background. We start by reviewing some general concepts of CFT, including the embedding space formalism. We then consider QFT in a fixed AdS background and show that one can define boundary operators that enjoy very similar properties as in a CFT, except for the lack of a stress tensor. Including a dynamical metric in AdS generates a boundary stress tensor and completes the CFT axioms. We also discuss some applications of the bulk geometric intuition to strongly coupled QFT. Finally, we end with a review of the main properties of Mellin amplitudes for CFT correlation functions and their uses in the context of AdS/CFT.

  1. Drug: D04684 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available D04684 Mixture, Drug Aluminum potassium sulfate hydrate - tannic acid mixt; Zione (TN) Aluminum...nts 255 Hemorrhoidal preparations 2559 Others D04684 Aluminum potassium sulfate hydrate - tannic acid mixt PubChem: 17398138 ...

  2. Condom ads promote illicit sex.

    Science.gov (United States)

    Kippley, J F

    1994-01-01

    Written in 1987, this opinion was republished in the wake of US President Bill Clinton's AIDS prevention media campaign promoting condom use which began January 1994, targeted at young adults aged 18-25. The author staunchly opposes condom use even though he admits that people do not consider abstinence from sex to be a serious option for the prevention of HIV/STD infection. He believes that there is no moral use of sex with a condom and that condoms have always been a sign of immorality, be it prostitution, adultery, fornication, or marital contraception. Likewise, the author laments the success enjoyed by Planned Parenthood in achieving the social acceptance of marital contraception and sex outside of marriage. The complete social acceptance of homosexual activity, however, remains to be achieved. Magazines, newspapers, and television receive income in exchange for publishing or airing advertisements. Finding offensive advertisements which promote the use of condoms against HIV infection, the author recommends writing letters of complaint to the responsible media sources. If the television stations or publications in question continue to advertise condoms to the public, stop watching them or end one's subscriptions to the particular printed media. Such action taken collectively among many individuals will reduce product sales and income, and potentially sway corporate policy against condom ads.

  3. Security Ads in Mobile Apps

    Directory of Open Access Journals (Sweden)

    Manasvi Kalra,

    2016-02-01

    Full Text Available The apps consist of advertisements to promote their products. Not all of them are appropriate to resume. Therefore various algorithms have been used in order to block those apps from existence but none of them is completely successful. In our app we are using an antivirus which can by default block those spy apps and remove them from the web page. The algorithm which has been used makes use of various ant viruses in the background which detect irrelevant and intimate apps and then our algorithm will demolish them. Certain apps are non-trustworthy where one click can spy all the mobile data. They block those apps and works on security. We are working on secure ads for mobile apps. It can also work as a basic antivirus where it detects the viruses like malwares in any of your installed apps or downloads. It will create a popup of discarding or keeping it. Mobile applications can be downloaded from anywhere like amazon, googleplay, apps store etc. There is no rigorous verification of an application when it is uploaded to the market. One can easily develop a malicious application and upload it to the app market. The user itself is responsible for accepting the risk of an app available from secondary markets. Therefore, we have decided to develop this app to make the market more secure and bounded. In future, It will take the mobile market while consuming minimal additional resources and preserving user privacy.

  4. Material Developing for ADS Beam Window

    Institute of Scientific and Technical Information of China (English)

    XUYong-li; XUYuan-chao; LIHua-qing; NINGGuang-sheng; WANFa-rong; ZHAOFei

    2003-01-01

    The irradiation damage and the chemical interaction with the coolant for the ADS target and the structure materials are the key issues in ADS engineering. The developing of the materials that are irradiation and corrosion resistance is the important topic in ADS program in many countries. In this case,a topic of the material developing for the beam window has been proposed in our ADS program.

  5. Myths & Facts about Value-Added Analysis

    Science.gov (United States)

    TNTP, 2011

    2011-01-01

    This paper presents myths as well as facts about value-added analysis. These myths include: (1) "Value-added isn't fair to teachers who work in high-need schools, where students tend to lag far behind academically"; (2) "Value-added scores are too volatile from year-to-year to be trusted"; (3) "There's no research behind value-added"; (4) "Using…

  6. Automated Experiments on Ad Privacy Settings

    Directory of Open Access Journals (Sweden)

    Datta Amit

    2015-04-01

    Full Text Available To partly address people’s concerns over web tracking, Google has created the Ad Settings webpage to provide information about and some choice over the profiles Google creates on users. We present AdFisher, an automated tool that explores how user behaviors, Google’s ads, and Ad Settings interact. AdFisher can run browser-based experiments and analyze data using machine learning and significance tests. Our tool uses a rigorous experimental design and statistical analysis to ensure the statistical soundness of our results. We use AdFisher to find that the Ad Settings was opaque about some features of a user’s profile, that it does provide some choice on ads, and that these choices can lead to seemingly discriminatory ads. In particular, we found that visiting webpages associated with substance abuse changed the ads shown but not the settings page. We also found that setting the gender to female resulted in getting fewer instances of an ad related to high paying jobs than setting it to male. We cannot determine who caused these findings due to our limited visibility into the ad ecosystem, which includes Google, advertisers, websites, and users. Nevertheless, these results can form the starting point for deeper investigations by either the companies themselves or by regulatory bodies.

  7. 16 CFR 460.18 - Insulation ads.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Insulation ads. 460.18 Section 460.18 Commercial Practices FEDERAL TRADE COMMISSION TRADE REGULATION RULES LABELING AND ADVERTISING OF HOME INSULATION § 460.18 Insulation ads. (a) If your ad gives an R-value, you must give the type of insulation...

  8. Ad-Coop Positioning System (ACPS)

    DEFF Research Database (Denmark)

    Frattasi, Simone; Monti, Marco

    2008-01-01

    In this paper, we propose an innovative solution for positioning determination in 4G wireless networks by introducing the Ad-Coop Positioning System (ACPS). The ACPS is supported by a hybrid cellular ad-hoc architecture, where the cellular network has a centralized control over the ad...

  9. Supergravity on $AdS_{5/4}$ x Hopf Fibrations and Conformal Field Theories

    CERN Document Server

    Halyo, E

    2000-01-01

    We obtain three and four dimensional conformal field theories with less than maximal supersymmetry by using their supergravity duals. These supergravity theories are type II on $AdS_5 \\times CP^2$, IIA on $AdS_4 \\times CP^3$, IIB on $AdS_5 \\times S^5/Z_k$ and D=11 supergravity on $AdS_4 \\times S^7/Z_k$. They are obtained from the spherically compactified ten and eleven dimensional theories by either Hopf reduction or by winding the U(1) fiber over the base.

  10. Supergravity on $AdS_{5/4} \\times$ Hopf Fibrations and Conformal Field Theories

    OpenAIRE

    1998-01-01

    We obtain three and four dimensional conformal field theories with less than maximal supersymmetry by using their supergravity duals. These supergravity theories are type II on $AdS_5 \\times CP^2$, IIA on $AdS_4 \\times CP^3$, IIB on $AdS_5 \\times S^5/Z_k$ and D=11 supergravity on $AdS_4 \\times S^7/Z_k$. They are obtained from the spherically compactified ten and eleven dimensional theories by either Hopf reduction or by winding the U(1) fiber over the base.

  11. Value added liquid products from waste biomass pyrolysis using pretreatments.

    Science.gov (United States)

    Das, Oisik; Sarmah, Ajit K

    2015-12-15

    Douglas fir wood, a forestry waste, was attempted to be converted into value added products by pretreatments followed by pyrolysis. Four different types of pretreatments were employed, namely, hot water treatment, torrefaction, sulphuric acid and ammonium phosphate doping. Subsequently, pyrolysis was done at 500°C and the resulting bio-oils were analysed for their chemical composition using Karl Fischer titration, thermogravimetry, ion exchange, and gas chromatography. Pretreatment with acid resulted in the highest yield of bio-oil (~60%). The acid and salt pretreatments were responsible for drastic reduction in the lignin oligomers and enhancement of water content in the pyrolytic liquid. The quantity of xylose/mannose reduced as a result of pretreatments. Although, the content of fermentable sugars remained similar across all the pretreatments, the yield of levoglucosan increased. Pretreatment of the biomass with acid yielded the highest amount of levoglucosan in the bio-oil (13.21%). The acid and salt pretreatments also elevated the amount of acetic acid in the bio-oils. Addition of acid and salt to the biomass altered the interaction of cellulose-lignin in the pyrolysis regime. Application of pretreatments should be based on the intended end use of the liquid product having a desired chemical composition.

  12. Protein domain organisation: adding order

    Directory of Open Access Journals (Sweden)

    Kummerfeld Sarah K

    2009-01-01

    Full Text Available Abstract Background Domains are the building blocks of proteins. During evolution, they have been duplicated, fused and recombined, to produce proteins with novel structures and functions. Structural and genome-scale studies have shown that pairs or groups of domains observed together in a protein are almost always found in only one N to C terminal order and are the result of a single recombination event that has been propagated by duplication of the multi-domain unit. Previous studies of domain organisation have used graph theory to represent the co-occurrence of domains within proteins. We build on this approach by adding directionality to the graphs and connecting nodes based on their relative order in the protein. Most of the time, the linear order of domains is conserved. However, using the directed graph representation we have identified non-linear features of domain organization that are over-represented in genomes. Recognising these patterns and unravelling how they have arisen may allow us to understand the functional relationships between domains and understand how the protein repertoire has evolved. Results We identify groups of domains that are not linearly conserved, but instead have been shuffled during evolution so that they occur in multiple different orders. We consider 192 genomes across all three kingdoms of life and use domain and protein annotation to understand their functional significance. To identify these features and assess their statistical significance, we represent the linear order of domains in proteins as a directed graph and apply graph theoretical methods. We describe two higher-order patterns of domain organisation: clusters and bi-directionally associated domain pairs and explore their functional importance and phylogenetic conservation. Conclusion Taking into account the order of domains, we have derived a novel picture of global protein organization. We found that all genomes have a higher than expected

  13. Flat Currents of Green-Schwarz Superstring in AdS2 × S2 Background

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    From the κ symmetric action of ⅡB string in AdS2 × S2 background given by Zhou, we derive the equations of motion. By using the twisted dual transformation which was introduced by Hou, we construct the flat currents, conserving non-local charge with one free parameter, for the superstring in AdS2 × S2.

  14. Joule-Thomson expansion of the charged AdS black holes

    Science.gov (United States)

    Ökcü, Özgür; Aydıner, Ekrem

    2017-01-01

    In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in the T- P plane and determine the cooling-heating regions.

  15. Joule-Thomson Expansion of Charged AdS Black Holes

    CERN Document Server

    Ökcü, Özgür

    2016-01-01

    In this paper, we study Joule-Thomson effects for charged AdS black holes. We obtain inversion temperatures and curves. We investigate similarities and differences between van der Waals fluids and charged AdS black holes for the expansion. We obtain isenthalpic curves for both systems in $T-P$ plane and determine the cooling-heating regions.

  16. Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space.

    Science.gov (United States)

    Herdeiro, Carlos A R; Radu, Eugen

    2016-11-25

    We explicitly construct static black hole solutions to the fully nonlinear, D=4, Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.

  17. Static Einstein-Maxwell Black Holes with No Spatial Isometries in AdS Space

    Science.gov (United States)

    Herdeiro, Carlos A. R.; Radu, Eugen

    2016-11-01

    We explicitly construct static black hole solutions to the fully nonlinear, D =4 , Einstein-Maxwell-anti-de Sitter (AdS) equations that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon (section), but without isometries, and approach, asymptotically, global AdS spacetime. They are interpreted as bound states of a horizon with the Einstein-Maxwell-AdS solitons recently discovered, for appropriate boundary data. In sharp contrast to the uniqueness results for a Minkowski electrovacuum, the existence of these black holes shows that single, equilibrium, black hole solutions in an AdS electrovacuum admit an arbitrary multipole structure.

  18. Effects of ad placement and type on consumer responses to podcast ads.

    Science.gov (United States)

    Ritter, Eric A; Cho, Chang-Hoan

    2009-10-01

    The purpose of this study was to understand the effects of podcast ad placement and podcast ad type on consumers' perceived intrusiveness, perceived irritation, attitude toward the ad, and ad avoidance. Our 2 x 2 (traditional ad vs. sponsorship by beginning vs. middle) experimental study found that sponsorships generated better consumer responses than did traditional ads and that podcast ads placed at the beginning of audio podcasts yielded better consumer responses than those placed in the middle. Implications for marketers and advertisers are discussed.

  19. AdS perturbations, isometries, selection rules and the Higgs oscillator

    Energy Technology Data Exchange (ETDEWEB)

    Evnin, Oleg [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand); Theoretische Natuurkunde, Vrije Universiteit Brussel and The International Solvay Institutes,Pleinlaan 2, B-1050 Brussels (Belgium); Nivesvivat, Rongvoram [Department of Physics, Faculty of Science, Chulalongkorn University,Thanon Phayathai, Pathumwan, Bangkok 10330 (Thailand)

    2016-01-25

    Dynamics of small-amplitude perturbations in the global anti-de Sitter (AdS) spacetime is restricted by selection rules that forbid effective energy transfer between certain sets of normal modes. The selection rules arise algebraically because some integrals of products of AdS mode functions vanish. Here, we reveal the relation of these selection rules to AdS isometries. The formulation we discover through this systematic approach is both simpler and stronger than what has been reported previously. In addition to the selection rule considerations, we develop a number of useful representations for the global AdS mode functions, with connections to algebraic structures of the Higgs oscillator, a superintegrable system describing a particle on a sphere in an inverse cosine-squared potential, where the AdS isometries play the role of a spectrum-generating algebra.

  20. Appropriate adding time of concentrated monosodium glutamate wastewater as acidity adjusting and nitrogen loss control agent in high temperature composting%浓缩味精废液作为高温堆肥调酸保氮剂的适宜添加时间研究

    Institute of Scientific and Technical Information of China (English)

    孔海民; 刘丽; 李田宇; 汪继兵; 方萍

    2016-01-01

    Summary The pH rise of the compost mixture is one of the main causes for nitrogen volatilization loss in the composting process.As a consequence of organic degradation,accumulated ammonium nitrogen will trigger pH rise spontaneously.It is generally believed that ammonia nitrogen (NH 3) will volatilize once the pH of compost mixture exceeds 8.0.And the higher the pH is,the more the NH3 volatilization will be.In this way,the pH rise of mixture will result in substandard compost products,not only because its pH is out of the upper limit(pH=8.5)of the NY 525—2012 standard,but also significant decline of nutrition content due to NH3 volatilization.Hence,adjusting the pH of materials to control nitrogen loss becomes one of the hot issues in the organic fertilizer industry.A lot of chemical agents have been applied to adjust the pH in composting.However,most of them are difficult to implement efficiency and decrease production cost,let alone the dilution effects and imbalance of nutrition.The concentrated monosodium glutamate wastewater (CMGW) is an evaporative and concentrated liquid waste from discharged organic water in production of monosodium glutamate,characterized by rich nutrients and free heavy metal pollution.Previous studies have indicated that CMGW is a promising conditioning agent to adjust acidity and reduce NH 3 volatilization for composting,and the suggested optimum dosage is 2% of the mixture in mass. The appropriate adding time of CMGW for adjusting pH and decreasing nitrogen loss due to NH 3 volatilization in composting was further discussed in present study by a compost simulation experiment.The simulation experiment took place in a composting device(patent number:ZL 201010589910X)with the mixture of fresh pig manure and mushroom residues at a ratio of 3∶1 in mass,as well as 1% fermentation bacterial agent of the mixture.Three treatments were conducted as follows:1) M1 ,application of 2% CMGW before composting;2) M2 ,application of 2% CMGW at the

  1. Perceived threat of Alzheimer disease (AD): the role of personal experience with AD.

    Science.gov (United States)

    Suhr, Julie A; Kinkela, Jessica H

    2007-01-01

    The fear of developing Alzheimer disease (AD) is highly salient, particularly for biologic family members. The current study evaluated social/cognitive explanations for perceived AD threat beyond genetic relatedness, including personal experience with AD, belief in negative aging stereotypes, and performance on delayed memory tasks. Participants were 97 healthy older adults aged 50 to 85, self-referred for a free community memory screen. Results showed that, as expected, personal AD experience was related to perceived AD threat. Furthermore, consistent with expectations, AD experience moderated the relationship between perceived AD threat and other explanatory variables, including age, belief in negative aging stereotypes, and cognitive performance. In those with AD experience, whether genetic or not, younger age was associated with more perceived AD threat, but an inverse relationship was seen in those without AD experience. Those with genetic AD experience seem particularly vulnerable to the effects of negative age stereotype beliefs on perceived AD threat, and show an inverse relationship between their actual cognitive performance and their perception of personal AD threat. Results highlight the importance of considering personal experience with AD when assessing a person's self-reported concerns about AD or his/her own memory changes.

  2. Exploring antismoking ads: appeals, themes, and consequences.

    Science.gov (United States)

    Beaudoin, Christopher E

    2002-01-01

    In this study we seek a descriptive understanding of antismoking television advertising in light of the problem cigarette consumption poses for society today. We establish relationships between ad characteristics and whether ads have a youth or adult orientation, based on a content analysis of 197 antismoking television advertisements produced between 1991 and 1999. The study finds that youth-oriented ads have youth characters, sociability, and humor as common appeals, and social and short-term consequences. In contrast, adult-oriented ads relied on fear appeals and long-term, health-related consequences.

  3. Suspected acute coronary syndrome in the emergency room: Limited added value of heart type fatty acid binding protein point of care or ELISA tests: The FAME-ER (Fatty Acid binding protein in Myocardial infarction Evaluation in the Emergency Room) study.

    Science.gov (United States)

    Bank, Ingrid Em; Dekker, Marieke S; Hoes, Arno W; Zuithoff, Nicolaas Pa; Verheggen, Peter Whm; de Vrey, Evelyn A; Wildbergh, Thierry X; Timmers, Leo; de Kleijn, Dominique Pv; Glatz, Jan Fc; Mosterd, Arend

    2016-08-01

    Timely recognition of acute coronary syndrome remains a challenge as many biomarkers, including troponin, remain negative in the first hours following the onset of chest pain. We assessed the diagnostic accuracy of heart-type fatty acid binding protein (H-FABP), a cardiac biomarker with potential value immediately post symptom onset. Prospective monocentre diagnostic accuracy study of H-FABP bedside point of care (CardioDetect®) and ELISA tests in acute coronary syndrome suspected patients presenting within 24 hours of symptom onset to the emergency department, in addition to clinical findings, electrocardiography and the currently recommended biomarker high sensitivity troponin-T (hs-cTnT). The final diagnosis of acute coronary syndrome was adjudicated by two independent cardiologists, blinded to H-FABP results. Acute coronary syndrome was diagnosed in 149 (32.9%) of 453 unselected patients with suspected acute coronary syndrome (56% men, mean age 62.6 years). Negative predictive values were similar for H-FABP point of care and ELISA tests (79% vs. 78% respectively), but inferior to initial hs-cTnT (negative predictive value 86%). The addition of H-FABP point of care results to hs-cTnT increased the negative predictive value to 89%. In a multivariable logistic regression model, H-FABP point of care and ELISA tests yielded relevant diagnostic information in addition to clinical findings and ECG (likelihood ratio test pcoronary syndrome presenting to the emergency department, H-FABP testing improves diagnostic accuracy in addition to clinical findings and electrocardiography. H-FABP, however, has no additional diagnostic value when hs-cTnT measurements are also available. © The European Society of Cardiology 2015.

  4. Waste valorization by biotechnological conversion into added value products.

    Science.gov (United States)

    Liguori, Rossana; Amore, Antonella; Faraco, Vincenza

    2013-07-01

    Fossil fuel reserves depletion, global warming, unrelenting population growth, and costly and problematic waste recycling call for renewable resources of energy and consumer products. As an alternative to the 100 % oil economy, production processes based on biomass can be developed. Huge amounts of lignocellulosic wastes are yearly produced all around the world. They include agricultural residues, food farming wastes, "green-grocer's wastes," tree pruning residues, and organic and paper fraction of urban solid wastes. The common ways currently adopted for disposal of these wastes present environmental and economic disadvantages. As an alternative, processes for adding value to wastes producing high added products should be developed, that is the upgrading concept: adding value to wastes by production of a product with desired reproducible properties, having economic and ecological advantages. A wide range of high added value products, such as enzymes, biofuels, organic acids, biopolymers, bioelectricity, and molecules for food and pharmaceutical industries, can be obtained by upgrading solid wastes. The most recent advancements of their production by biotechnological processes are overviewed in this manuscript.

  5. From path integrals to tensor networks for the AdS /CFT correspondence

    Science.gov (United States)

    Miyaji, Masamichi; Takayanagi, Tadashi; Watanabe, Kento

    2017-03-01

    In this paper, we discuss tensor network descriptions of AdS /CFT from two different viewpoints. First, we start with a Euclidean path-integral computation of ground state wave functions with a UV cutoff. We consider its efficient optimization by making its UV cutoff position dependent and define a quantum state at each length scale. We conjecture that this path integral corresponds to a time slice of anti-de Sitter (AdS) spacetime. Next, we derive a flow of quantum states by rewriting the action of Killing vectors of AdS3 in terms of the dual two-dimensional conformal field theory (CFT). Both approaches support a correspondence between the hyperbolic time slice H2 in AdS3 and a version of continuous multiscale entanglement renormalization ansatz. We also give a heuristic argument about why we can expect a sub-AdS scale bulk locality for holographic CFTs.

  6. Green approach to corrosion inhibition of mild steel in two acidic solutions by the extract of Punica granatum peel and main constituents

    Energy Technology Data Exchange (ETDEWEB)

    Behpour, M., E-mail: m.behpour@kashanu.ac.ir [Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, I.R. 87317-51167 (Iran, Islamic Republic of); Ghoreishi, S.M.; Khayatkashani, M. [Department of Analytical Chemistry, Faculty of Chemistry, University of Kashan, Kashan, I.R. 87317-51167 (Iran, Islamic Republic of); Soltani, N. [Department of Chemistry, Payame Noor University (PNU), 19395-4697 Tehran (Iran, Islamic Republic of)

    2012-01-05

    Graphical abstract: Ellagic acid (EA) and tannic acid (TA) were studied as corrosion inhibitors. The electron density HOMO and LUMO of EA and TA were used to explain difference in behavior of them. Highlights: Black-Right-Pointing-Pointer The extract of Punica granatum (PG) and their main constituent (ellagic acid (EA)) are found to be good inhibitors for the corrosion of mild steel in 1 M H{sub 2}SO{sub 4} and 2 M HCl. Black-Right-Pointing-Pointer The electrochemical inhibitive mechanism is explained by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) results. Black-Right-Pointing-Pointer The adsorption of ALLOX on mild steel surface was found to accord with the Temkin adsorption isotherm. Black-Right-Pointing-Pointer The effect of temperature on the corrosion behavior of mild steel in 2 M HCl and 1 M H{sub 2}SO{sub 4} without and with the PG extract was studied. - Abstract: The effect of the extract of Punica granatum (PG) and their main constituents involve ellagic acid (EA) and tannic acid (TA), as mild steel corrosion inhibitor in 2 M HCl and 1 M H{sub 2}SO{sub 4} solutions was investigated by weight loss measurements. The results obtained from the weight loss measurements show that the inhibition efficiency of TA even in high concentration is very low. Thus, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) investigations were used for different concentrations of PG and EA and best concentration of TA. Potentiodynamic polarization curves indicated that PG and EA behave as mixed-type inhibitors. EIS measurements show an increase of the transfer resistance with increasing inhibitor concentration. The temperature effect on the corrosion behavior of steel without and with the PG extract was studied. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm.

  7. Justidrusamides A-D, new 2-aminobenzyl alcohol derivatives from Justicia gendarussa.

    Science.gov (United States)

    Kiren, Yuko; Deguchi, Jun; Hirasawa, Yusuke; Morita, Hiroshi; Prajogo, Bambang

    2014-10-01

    Justidrusamides A-D (1-4), four new alkaloids containing 2-aminobenzyl alcohol, succinic acid, and 2,3-dihydroxy-2-(1-hydroxyethyl) butanoic acid skeletons have been isolated from leaves of Justicia gendarussa, and their structures were elucidated using 2D NMR data and chemical means. This is the first report of a 2,3-dihydroxy-2-(1-hydroxyethyl) butanoic acid derivative in nature.

  8. Value added meat marketing around the globe

    DEFF Research Database (Denmark)

    Grebitus, Carola; Mueller Loose, Simone

    In highly competitive meat markets it is important to offer value added products to consumers. Thus, we need to understand which attributes are especially valued by consumers. This track session will contribute to a better understanding of consumer preferences for value added meats across differe...

  9. Status Report on the Antiproton Decelerator (AD)

    CERN Document Server

    Erikson, T; Möhl, D

    2001-01-01

    CERN's new Antiproton Decelerator (AD) has been delivering a 100 MeV/c antiproton beam to three experiments (ASACUSA, AHENA and ATRAP) since July 10th, 2000. In this status report, we summarise the initial performance of the AD, draw provisional conclusions from the first month of operation and finally give some prospects for the future.

  10. On circular strings in (AdS3 × S 3)ϰ

    Science.gov (United States)

    Banerjee, Aritra; Panigrahi, Kamal L.

    2016-09-01

    The so called one-parameter (often called ϰ) deformed AdS string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the (AdS3 × S 3) ϰ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the ϰ-deformed AdS3 and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.

  11. On circular strings in $(AdS_3 \\times S^3)_{\\varkappa}$

    CERN Document Server

    Banerjee, Aritra

    2016-01-01

    The so called one-parameter (often called $\\varkappa$) deformed $AdS$ string sigma models have attracted a lot of attention lately in the study of integrability in string theory. We construct various circular string solutions in the $(AdS_3 \\times S^3)_{\\varkappa}$ background and describe the characteristics of such solutions qualitatively. We study the Bohr-Sommerfeld like quantization for these string states to characterise the motion. Further we find a `long' string limit of such circular strings in the $\\varkappa$-deformed $AdS_3$ and find a novel dependence of the oscillation number on the energy in the next to leading order expansion.

  12. Various types of phase transitions in the AdS soliton background

    CERN Document Server

    Peng, Yan; Wang, Bin

    2011-01-01

    We study the basic holographic insulator and superconductor phase transition in the AdS soliton background by generalizing the spontaneous breaking of a global U(1) symmetry to occur via St$\\ddot{u}$ckelberg mechanism. We construct the soliton solutions with backreaction and examine the effects of the backreaction on the condensation of the scalar hair in the generalized St$\\ddot{u}$ckelberg Lagrangian. We disclose rich physics in various phase transitions. In addition to the AdS soliton configuration, we also examine the property of the phase transition in the AdS black hole background.

  13. Thermodynamic geometry and phase transitions of AdS braneworld black holes

    Science.gov (United States)

    Chaturvedi, Pankaj; Sengupta, Gautam

    2017-02-01

    The thermodynamics and phase transitions of charged RN-AdS and rotating Kerr-AdS black holes in a generalized Randall-Sundrum braneworld are investigated in the framework of thermodynamic geometry. A detailed analysis of the thermodynamics, stability and phase structures in the canonical and the grand canonical ensembles for these AdS braneworld black holes are described. The thermodynamic curvatures for both these AdS braneworld black holes are computed and studied as a function of the thermodynamic variables. Through this analysis we illustrate an interesting dependence of the phase structures on the braneworld parameter for these black holes.

  14. Google Advertising Tools Cashing in with AdSense and AdWords

    CERN Document Server

    Davis, Harold

    2010-01-01

    With this book, you'll learn how to take full advantage of Google AdWords and AdSense, the sophisticated online advertising tools used by thousands of large and small businesses. This new edition provides a substantially updated guide to advertising on the Web, including how it works in general, and how Google's advertising programs in particular help you make money. You'll find everything you need to work with AdWords, which lets you generate text ads to accompany specific search term results, and AdSense, which automatically delivers precisely targeted text and image ads to your website.

  15. Entropy of Warped Taub-NUT AdS Black String via the Brick Wall Method

    CERN Document Server

    Lee, Chong Oh

    2014-01-01

    When we consider five-dimensional warped Taub-NUT AdS black string with minimally coupled massive scalar field, we calculate an entropy by using the brick wall method. In extremely light effective mass, we find the entropy is proportional to an extra dimension wave number as well as quadratically divergent in a cutoff parameter. After taking zero NUT charge, we find the entropy of warped (AdS) Schwartzshield black hole string has a similar properties in as warped Taub-NUT AdS black string.

  16. Holographic complexity and fidelity susceptibility as holographic information dual to different volumes in AdS

    Directory of Open Access Journals (Sweden)

    N.S. Mazhari

    2017-03-01

    Full Text Available The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution, a solution with cylindrical symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not have any such dependence.

  17. Beyond the unitarity bound in AdS/CFT{sub (A)dS}

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Tomas [University of California, Santa Barbara (United States); Uhlemann, Christoph [Universitaet Wuerzburg (Germany)

    2012-07-01

    We study CFTs on dS and AdS spacetimes from a holographic perspective, in particular how the unitarity properties of the boundary theory are reflected in the bulk description. On geometries with an (A)dS conformal boundary we choose mass and boundary conditions for a Klein-Gordon field such that the corresponding CFT operator violates the unitarity bound. We analyze how the non-unitarity is reproduced in the bulk and discuss, for the case of an AdS boundary, prospects for multi-layered AdS/CFT-type dualities.

  18. Phase Transition and Clapeyon Equation of Black Hole in Higher Dimensional AdS Spacetime

    CERN Document Server

    Zhao, Hui-Hua; Ma, Meng-Sen; Zhao, Ren

    2014-01-01

    By Maxwell equal area law we study the phase transition in higher dimensional Anti-de Sitter (AdS) Reissner-Nordstr\\"{o}m (RN) black hole and Kerr black hole in this paper. The coexisting region of the two phases involved in the phase transition is found and the coexisting curves are shown in $P-T$ figures. We also analytically investigate the parameters which affect the coexisting curves. To better compare with ordinary thermodynamic systems, the Clapeyon equation is derived for higher dimensional AdS black holes. This paper can help to deepen the understanding of the phase transition and phase structure of AdS black holes.

  19. Boundary action of free AdS higher-spin gauge fields and the holographic correspondence

    CERN Document Server

    Joung, Euihun

    2011-01-01

    We determine the boundary terms of the free higher-spin action which reproduce the AdS Fronsdal equations in an AdS manifold with a finite distance boundary. The boundary terms are further constrained by the gauge invariance of the total action. We show that, for spins larger than two, no local boundary term can restore the full gauge symmetry, and the broken symmetry corresponds to higher-spin Weyl transformations on the boundary CFT. The boundary action is used for the evaluation of the on-shell higher-spin AdS action in terms of the boundary data given by a conformal higher-spin field.

  20. Geometric Finiteness, Holography and Quasinormal Modes for the Warped AdS_3 Black Hole

    CERN Document Server

    Gupta, Kumar S; Sen, Siddhartha; Sivakumar, M

    2009-01-01

    We show that there exists a precise kinematical notion of holography for the Euclidean warped $AdS_3$ black hole. This follows from the fact that the Euclidean warped $AdS_3$ black hole spacetime is a geometrically finite hyperbolic manifold. For such manifolds a theorem of Sullivan provides a one-to-one correspondence between the hyperbolic structure in the bulk and the conformal structure of its boundary. Using this theorem we obtain the holographic quasinormal modes for the warped $AdS_3$ black hole.

  1. An improved AFS phase for AdS3 string integrability

    CERN Document Server

    Abbott, Michael C

    2015-01-01

    We propose a number of modifications to the classical term in the dressing phase for integrable strings in AdS3 x S3 x S3 x S1, and check these against existing perturbative calculations, crossing symmetry, and the semiclassical limit of the Bethe equations. The principal change is that the phase for different masses should start with a term Q_1 Q_2, like the one-loop AdS3 dressing phase, rather than Q_2 Q_3 as for the original AdS5 AFS phase.

  2. Holographic Complexity and Fidelity Susceptibility as Holographic Information Dual to Different Volumes in AdS

    CERN Document Server

    Mazhari, N S; Bahamonde, Sebastian; Faizal, Mir; Myrzakulov, Ratbay

    2016-01-01

    The holographic complexity and fidelity susceptibility have been defined as new quantities dual to different volumes in AdS. In this paper, we will use these new proposals to calculate both of these quantities for a variety of interesting deformations of AdS. We obtain the holographic complexity and fidelity susceptibility for an AdS black hole, Janus solution and a solution with cylindrically symmetry, an inhomogeneous background and a hyperscaling violating background. It is observed that the holographic complexity depends on the size of the subsystem for all these solutions and the fidelity susceptibility does not any such dependence.

  3. [Rapid analysis of added ingredients in heroin].

    Science.gov (United States)

    Wang, Ji-fen; Yu, Jing; Guo, Xin; Sun, Xing-long; Wang, Ding-fang

    2011-07-01

    The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives were determined. Whether or not heroin can be detected in the sample with high concentration of added ingredients was studied using Raman spectroscopy. Similarly, in high purity of heroin, whether or not Raman spectroscopy can detect the added ingredients was tested. Through systematic experiments, the results showed that: using infrared spectroscopy and Raman spectroscopy to test the added ingredients of heroin is a rapid and effective method. Each has both advantages and disadvantages. We should select the appropriate method according to the actual cases.

  4. The concept of added value of FM

    DEFF Research Database (Denmark)

    2012-01-01

    Purpose: This chapter presents research perspectives and theoretical reflections on the concept of added value of FM from a variety of academic fields. Methodology: A literature review of the most influential journals within the academic fields of Facilities Management (FM), Corporate Real Estate...... conceptualization of the concept of added value of FM is of utmost importance for further research into the added value of FM and well-considered, evidence- based Value Adding Management in practice. Research limitations: Due to limited time not all FM-related journals could be included in the literature review...... Management (CREM) and Business to Business Marketing (B2B Marketing). Findings: The research shows different definitions and focus points, dependent on the academic field and the area of application. The different research perspectives explored a holistic view on the added value of FM by the integration...

  5. Inflation in AdS/CFT

    Energy Technology Data Exchange (ETDEWEB)

    Freivogel, Ben; /Stanford U., Phys. Dept. /LBL, Berkeley; Hubeny, Veronika E.; /LBL, Berkeley /Durham U., Dept. of Math.; Maloney, Alexander; /Stanford U., Phys. Dept.; Myers, Rob; /Perimeter Inst. Theor. Phys. /Waterloo U.; Rangamani, Mukund; /LBL, Berkeley /Durham U., Dept. of Math.; Shenker, Stephen; /Stanford U., Phys. Dept.

    2005-10-07

    We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.We study the realization of inflation within the AdS/CFT correspondence. We assume the existence of a string landscape containing at least one stable AdS vacuum and a (nearby) metastable de Sitter state. Standard arguments imply that the bulk physics in the vicinity of the AdS minimum is described by a boundary CFT. We argue that large enough bubbles of the dS phase, including those able to inflate, are described by mixed states in the CFT. Inflating degrees of freedom are traced over and do not appear explicitly in the boundary description. They nevertheless leave a distinct imprint on the mixed state. Analytic continuation allows us, in principle, to recover a large amount of nonperturbatively defined information about the inflating regime. Our work also shows that no scattering process can create an inflating region, even by quantum tunneling, since a pure state can never evolve into a mixed state under unitary evolution.

  6. A Grassmann Path From AdS$_3$ to Flat Space

    CERN Document Server

    Krishnan, Chethan; Roy, Shubho

    2013-01-01

    We show that interpreting the inverse AdS$_3$ radius $1/l$ as a Grassmann variable results in a formal map from gravity in AdS$_3$ to gravity in flat space. The underlying reason for this is the fact that $ISO(2,1)$ is the Inonu-Wigner contraction of $SO(2,2)$. We show how this works for the Chern-Simons actions, demonstrate how the general (Banados) solution in AdS$_3$ maps to the general flat space solution, and how the Killing vectors, charges and the Virasoro algebra in the Brown-Henneaux case map to the corresponding quantities in the BMS$_3$ case. Our results straightforwardly generalize to the higher spin case: the recently constructed flat space higher spin theories emerge automatically in this approach from their AdS counterparts. We conclude with a discussion of singularity resolution in the BMS gauge as an application.

  7. Quantum corrections to supergravity on AdS2×S2

    Science.gov (United States)

    Larsen, Finn; Lisbão, Pedro

    2015-04-01

    We compute the off-shell spectrum of supergravity on AdS2×S2 by explicit diagonalization of the equations of motion for an effective AdS2 theory where all fields are dualized to scalars and spin-1/2 fermions. We classify all bulk modes as physical, gauge violating, and pure gauge then compute the physical spectrum by explicit cancellation of unphysical modes. We identify boundary modes as physical fields on S2 that are formally pure gauge but with gauge function that is non-normalizable on AdS2. As an application we compute the leading quantum correction to AdS2×S2 as a sum over physical fields including boundary states. The result agrees with a previous computation by Sen [1] where unphysical modes were canceled by ghosts.

  8. Impaired cognition in depression and Alzheimer (AD: a gradient from depression to depression in AD

    Directory of Open Access Journals (Sweden)

    Narahyana Bom de Araujo

    2014-09-01

    Full Text Available Objective To assess cognition in major depressed (MD, Alzheimer's disease (AD, and depression in AD elderly. Method Subjects were evaluated by Mini Mental, Rey Auditory Verbal Learning Test, Rey Complex Figure, Digit Span, Similarities, Trail Making A/B, Verbal Fluency and Stroop. One-way ANOVA and multivariate models were used to compare the performance of each group on neuropsychological tests. Results We evaluated 212 subjects. Compared to MD, attention, working memory, processing speed and recall showed significantly better in controls. Controls showed significantly higher performance in all cognitive measures, except in attention compared to AD. Verbal fluency, memory, processing speed and abstract reasoning in MD was significantly higher compared to AD. AD was significantly better in general cognitive state than depression in AD. All other cognitive domains were similar. Conclusion A decreasing gradient in cognition appeared from the control to depression in AD, with MD and AD in an intermediate position.

  9. Study of ADS-B Data Evaluation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jun; LIU Wei; ZHU Yanbo

    2011-01-01

    In western China,the terrain and meteorological conditions are so complex that it is not suitable to construct new radar stations.Automatic dependent surveillance-broadcast(ADS-B) is a totally new surveillance method,so before practically applied and operated in China,abundant tests and evaluations are necessary to validate the performance of ADS-B and guarantee the operational security.During the flight tests,we collect the data of radar,ADS-B and high accuracy position and compare the performance of ADS-B with radar based on high accuracy position.To solve the asynchronous problem among radar data,ADS-B data and real-time kinematic(RTK) data caused by different update rates,this article proposes the technique of synchronizing multi-surveil- lance data by extrapolating from the data of low update rate to high update rate according to velocity and heading.Meanwhile,because radar data,ADS-B data and RTK data are expressed in different coordinates and cannot be compared each other,this article provides a method to unifying the coordinates of multi-surveillance data.By the analysis and evaluation,we can conclude that the performance of ADS-B is better than radar.

  10. Supergravity background of the lambda-deformed AdS_3 x S^3 supercoset

    CERN Document Server

    Chervonyi, Yuri

    2016-01-01

    We construct the solution of type IIB supergravity describing the integrable lambda-deformation of the AdS_3 x S^3 supercoset. While the geometry corresponding to the deformation of the bosonic coset has been found in the past, our background is more natural for studying superstrings, and several interesting features distinguish our solution from its bosonic counterpart. We also report progress towards constructing the lambda-deformation of the AdS_5 x S^5 supercoset.

  11. Ad Hoc Network Securing Policy%Ad hoc网络安全策略

    Institute of Scientific and Technical Information of China (English)

    刘志远; 张曼曼

    2006-01-01

    本文首先介绍了Ad hoc网络的产生、定义、特点和应用,然后在探讨Ad hoc网络的安全需求的基础上,着重分析了移动Ad hoc网络易于遭受的攻击,最后讨论并提出了Ad Hoc网络的一些安全策略.

  12. Yangian of AdS_3/CFT_2 and its deformation

    CERN Document Server

    Regelskis, Vidas

    2015-01-01

    We construct highest-weight modules and a Yangian extension of the centrally extended superalgebra appearing in the worldsheet scattering associated with the AdS_3 /CFT_2 duality, and show a link to the Yangian of AdS_5/CFT_4. We also consider a quantum deformation of this superalgebra, its modules and a quantum affine extension of the Drinfeld-Jimbo type which describes deformed worldsheet scattering.

  13. Advanced oxidation (H₂O₂ and/or UV) of functionalized carbon nanotubes (CNT-OH and CNT-COOH) and its influence on the stabilization of CNTs in water and tannic acid solution.

    Science.gov (United States)

    Czech, Bożena; Oleszczuk, Patryk; Wiącek, Agnieszka

    2015-05-01

    The properties of carbon nanotubes (CNTs) functionalized with -OH and -COOH groups during simulated water treatment with H2O2 and/or UV were tested. There following properties of CNTs were investigated: specific surface area, elemental composition (CHN), dynamic light scattering, Raman spectroscopy, X-ray photoelectron spectroscopy and changes in the CNTs structure were observed using transmission electron microscopy. Treatment of CNTs with H2O2 and/or UV affected their properties. This effect, however, was different depending on the functionalization of CNTs and also on the factor used (UV and/or H2O2). H2O2 plays a key role as a factor modifying the surface of CNT-OHs, whereas the properties of CNT-COOHs were most affected by UV rays. A shortening of the nanotubes, exfoliation, the opening of their ends, and changes in the surface charge were observed as a result of the action of UV and/or H2O2. The changes in observed parameters may influence the stability of the aqueous suspensions of CNTs.

  14. Half BPS states in AdS_5 x Y^{p,q}

    CERN Document Server

    Gava, Edi; Milanesi, Giuseppe; O'Loughlin, Martin

    2008-01-01

    We study a class of solutions of IIB Supergravity which are asymptotically AdS_5 x Y^{p,q}. They have an R x SO(4) x SU(2) x U(1) isometry and preserve half of the 8 supercharges of the background geometry. They are described by a set of second order differential equations that we have found and analysed in a previous paper, where we studied 1/8 BPS states in the maximally supersymmetric AdS_5 x S^5 background. These geometries correspond to certain chiral primary operators of the N=1 superconformal quiver theories, dual to IIB theory on AdS_5 x Y^{p,q}. We also show how to recover the AdS_5 x Y^{p,q} backgrounds by suitably doubling the number of preserved supersymmetries. We then solve the differential equations perturbatively in a large AdS_5 radius expansion, imposing asymptotic AdS_5 x Y^{p,q} boundary conditions. We compute the global baryonic and mesonic charges, including the R-charge. As for the computation of the mass, i.e. the conformal dimension D of the dual field theory operators, which is notor...

  15. Service placement in ad hoc networks

    CERN Document Server

    Wittenburg, Georg

    2012-01-01

    Service provisioning in ad hoc networks is challenging given the difficulties of communicating over a wireless channel and the potential heterogeneity and mobility of the devices that form the network. Service placement is the process of selecting an optimal set of nodes to host the implementation of a service in light of a given service demand and network topology. The key advantage of active service placement in ad hoc networks is that it allows for the service configuration to be adapted continuously at run time. ""Service Placement in Ad Hoc Networks"" proposes the SPi service placement fr

  16. Value added meat marketing around the globe

    DEFF Research Database (Denmark)

    Grebitus, Carola; Mueller Loose, Simone

    In highly competitive meat markets it is important to offer value added products to consumers. Thus, we need to understand which attributes are especially valued by consumers. This track session will contribute to a better understanding of consumer preferences for value added meats across different...... countries and simultaneously address different stages of the food chain by acknowledging factors such as breeding, forage (fat content), meat cuts as well as product labelling and packaging. Comparing consumers’ choices for value added pork and beef across different countries is the main theme and focus...

  17. Trust Based Routing in Ad Hoc Network

    Science.gov (United States)

    Talati, Mikita V.; Valiveti, Sharada; Kotecha, K.

    Ad Hoc network often termed as an infrastructure-less, self- organized or spontaneous network.The execution and survival of an ad-hoc network is solely dependent upon the cooperative and trusting nature of its nodes. However, this naive dependency on intermediate nodes makes the ad-hoc network vulnerable to passive and active attacks by malicious nodes and cause inflict severe damage. A number of protocols have been developed to secure ad-hoc networks using cryptographic schemes, but all rely on the presence of trust authority. Due to mobility of nodes and limitation of resources in wireless network one interesting research area in MANET is routing. This paper offers various trust models and trust based routing protocols to improve the trustworthiness of the neighborhood.Thus it helps in selecting the most secure and trustworthy route from the available ones for the data transfer.

  18. Introduction to AdS-CFT

    CERN Document Server

    Nastase, Horatiu

    2007-01-01

    These lectures present an introduction to AdS-CFT, and are intended both for begining and more advanced graduate students, which are familiar with quantum field theory and have a working knowledge of their basic methods. Familiarity with supersymmetry, general relativity and string theory is helpful, but not necessary, as the course intends to be as self-contained as possible. I will introduce the needed elements of field and gauge theory, general relativity, supersymmetry, supergravity, strings and conformal field theory. Then I describe the basic AdS-CFT scenario, of ${\\cal N}=4 $ Super Yang-Mills's relation to string theory in $AdS_5\\times S_5$, and applications that can be derived from it: 3-point functions, quark-antiquark potential, finite temperature and scattering processes, the pp wave correspondence and spin chains. I also describe some general properties of gravity duals of gauge theories.

  19. Heat kernels on cone of AdS2 and k-wound circular Wilson loop in AdS5 × S5 superstring

    Science.gov (United States)

    Bergamin, R.; Tseytlin, A. A.

    2016-04-01

    We compute the one-loop world-sheet correction to partition function of {{AdS}}5× {{{S}}}5 superstring that should be representing k-fundamental circular Wilson loop in planar limit. The 2d metric of the minimal surface ending on k-wound circle at the boundary is that of a cone of AdS2 with deficit 2π (1-k). We compute the determinants of 2d fluctuation operators by first constructing heat kernels of scalar and spinor Laplacians on the cone using the Sommerfeld formula. The final expression for the k-dependent part of the one-loop correction has simple integral representation but is different from earlier results.

  20. Profiling value added position in FM

    DEFF Research Database (Denmark)

    Katchamart, Akarapong

    organizations can best add value. Based on comprehensive literature studies and 7 case studies of private and public organisations from Denmark, Holland, Hong Kong and Thailand, the dissertation analyses, how FM organizations can best create added value. From the analyses the following four value added...... - FM organizations influence the business productivities and outcome Each type of value added requires specific conditions and contingencies involved. This research thus offers a visual aid tool, “FM product-process matrix”, to assist practitioners to indicate their existing circumstances and contexts...... the unarticulated notions of added value from FM organization and activities. It will broaden the managerial perception and discussion on FM provision ´s abilities and capabilities. The results are besides the field of FM also of relevance for management of other service industries and functions....

  1. Heat kernels on cone of $AdS_2$ and $k$-wound circular Wilson loop in $AdS_5 \\times S^5$ superstring

    CERN Document Server

    Bergamin, R

    2015-01-01

    We compute the one-loop world-sheet correction to partition function of $AdS_5 \\times S^5$ superstring that should be representing $k$-fundamental circular Wilson loop in planar limit. The 2d metric of the minimal surface ending on $k$-wound circle at the boundary is that of a cone of $AdS_2$ with deficit $2\\pi (1-k)$. We compute determinants of 2d fluctuation operators by first constructing heat kernels of scalar and spinor Laplacians on the cone using the Sommerfeld formula. The final expression for the k-dependent part of the one-loop correction has simple integral representation but is different from earlier results.

  2. Multilevel security model for ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Wang Changda; Ju Shiguang

    2008-01-01

    Modern battlefield doctrine is based on mobility, flexibility, and rapid response to changing situations.As is well known, mobile ad hoc network systems are among the best utilities for battlefield activity. Although much research has been done on secure routing, security issues have largely been ignored in applying mobile ad hoc network theory to computer technology. An ad hoc network is usually assumed to be homogeneous, which is an irrational assumption for armies. It is clear that soldiers, commanders, and commanders-in-chief should have different security levels and computation powers as they have access to asymmetric resources. Imitating basic military rank levels in battlefield situations, how multilevel security can be introduced into ad hoc networks is indicated, thereby controlling restricted classified information flows among nodes that have different security levels.

  3. The Tetrahedral Zamolodchikov Algebra and the {AdS_5× S^5} S-matrix

    Science.gov (United States)

    Mitev, Vladimir; Staudacher, Matthias; Tsuboi, Zengo

    2017-08-01

    The S-matrix of the {AdS_5× S^5} string theory is a tensor product of two centrally extended su{(2|2)\\ltimes R^2 S-matrices, each of which is related to the R-matrix of the Hubbard model. The R-matrix of the Hubbard model was first found by Shastry, who ingeniously exploited the fact that, for zero coupling, the Hubbard model can be decomposed into two XX models. In this article, we review and clarify this construction from the AdS/CFT perspective and investigate the implications this has for the {AdS_5× S^5} S-matrix.

  4. The Tetrahedron Zamolodchikov Algebra and the AdS5 x S5 S-matrix

    CERN Document Server

    Mitev, Vladimir; Tsuboi, Zengo

    2012-01-01

    The S-matrix of the AdS5 x S5 string theory is a tensor product of two centrally extended su(2|2) S-matrices, each of which is related to the R-matrix of the Hubbard model. The R-matrix of the Hubbard model was first found by Shastry, who ingeniously exploited the fact that, for zero coupling, the Hubbard model can be decomposed into two XX models. In this article, we review and clarify this construction from the AdS/CFT perspective and investigate the implications this has for the AdS5 x S5 S-matrix.

  5. Adding stress plot function to NASTRAN

    Science.gov (United States)

    Katoh, S.

    1978-01-01

    Stress plot function was developed and added to the NASTRAN level 15.5. Computed stress distribution can be displayed by this function, with vectors showing the principal stresses of the finite elements over the specified portions of the structure. NASTRAN is reviewed in the aspect of plotting capabilities. Stress tensor field is examined in preparation of stress display. Then the stress plot function as added to the NASTRAN is described. A sample plotout by this function is shown.

  6. Evaluation of co-added astronomical images

    Science.gov (United States)

    Nasyrova, M.; Vítek, S.

    2017-07-01

    The co-adding, averaging, or stacking of data are popular techniques to improve scientific outcomes in astronomy, especially in the case of extraction of very faint sources. These methods allow to increase the signal-to-noise ratio and to decrease the point spread function width, which improves the accuracy of segmentation. This paper deals with a brief review of image co-adding algorithms and their evaluation regarding improving the qualitative parameters of the image data.

  7. AdS-Sliced Flavor Branes and Adding Flavor to the Janus Solution

    CERN Document Server

    Clark, Adam B; Newman, George M; Rommal, Andrea

    2014-01-01

    We implement D7 flavor branes in AdS-sliced coordinates on $AdS_5\\times S^5$ with the ansatz that the brane fluctuates only in the warped ($\\mu$) direction in this slicing, which is particularly appropriate for studying the Janus solution. The natural field theory dual in this slicing is $\\mathcal{N}=4$ super Yang-Mills on two copies of $AdS_4$. Branes extending from $\\mu=\\pm\\pi/2$ can end at different locations, giving rise to quarks with piecewise constant mass on each $AdS_4$ half-space, jumping discontinuously between them. A second class of flavor brane solutions exists in this coordinate system, dubbed "continuous" flavor branes, that extend across the entire range of $\\mu$. We propose that the correct dual interpretation of "disconnected" flavor brane in this ansatz is a quark hypermultiplet with constant mass on one of the AdS$_4$ half-spaces with totally reflecting boundary conditions at the boundary of AdS$_4$; whereas the dual interpretation of a continuous flavor brane has totally transparent boun...

  8. Integrable strings for AdS/CFT

    CERN Document Server

    Borsato, Riccardo

    2016-01-01

    In this PhD thesis we review some aspects of integrable models related to string backgrounds or their deformations. In the first part we develop methods to obtain exact results in the AdS3/CFT2 correspondence. We consider the AdS_3 x S^3 x T^4 background with pure Ramond-Ramond flux and we find the all-loop worldsheet S-matrix by exploiting the symmetries of the model in light-cone gauge. As we naturally include the massless modes on the worldsheet, we derive the full set of Bethe-Yang equations. In the massive sector we give also a spin-chain description and we write down solutions compatible with crossing for the scalar factors which are not constrained by simmetries. In the second part of the thesis we consider the so-called "eta-deformation" of the superstring on AdS_5 x S^5. We first discuss the effects of the deformation at the level of the bosonic sigma-model, and we match the tree-level worldsheet scattering processes to the expansion of the q-deformed S-matrix. To identify the missing Ramond-Ramond f...

  9. Brick Walls and AdS/CFT

    CERN Document Server

    Kay, Bernard S

    2011-01-01

    We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other 'fixed-background' approaches to holography) and in mainstream 'Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the viewpoint of QFT in curved spacetime -- in the framework of 't Hooft's 'brick wall' model -- with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein Gordon field in the Hartle-Hawking-Israel state on 1+2-Schwarzschild AdS (BTZ) has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the 'correspondence principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to...

  10. Gauge Symmetries and Holographic Anomalies of Chern-Simons and Transgression AdS Gravity

    CERN Document Server

    Mora, Pablo

    2014-01-01

    We review the issue of gauge and gravitational anomalies with backgrounds, maybe offering a new outlook on some aspects of these questions. We compute the holographic anomalies of hypothetical theories dual, in the sense of the AdS-CFT correspondence, to Chern-Simons AdS gravities. Those anomalies are either gauge anomalies associated to the AdS gauge group of the theory or diffeomorphism anomalies, with each kind related to the other. As a result of using suitable action principles por Chern-Simons AdS gravities, coming from Transgression forms, we obtain finite results without the need for further regularization. Our results are of potential interest for Lovelock gravity theories, as it has been shown that the boundary terms dictated by the transgressions for Chern-Simons gravities are also suitable to regularize Lovelock theories. The Wess-Zumino consistency condition ensures that anomalies of the generic form computed here should appear for these and other theories.

  11. AdS5×S(5) mirror model as a string sigma model.

    Science.gov (United States)

    Arutyunov, Gleb; van Tongeren, Stijn J

    2014-12-31

    Doing a double Wick rotation in the world sheet theory of the light cone AdS5×S(5) superstring results in an inequivalent, so-called mirror theory that plays a central role in the field of integrability in the AdS-CFT correspondence. We show that this mirror theory can be interpreted as the light cone theory of a free string on a different background. This background is related to dS5×H(5) by a double T-duality, and has hidden supersymmetry. The geometry can also be extracted from an integrable deformation of the AdS5×S(5) sigma model, and we prove the observed mirror duality of these deformed models at the bosonic level as a byproduct. While we focus on AdS5×S(5), our results apply more generally.

  12. On Thermodynamics of AdS Black Holes in M-Theory

    CERN Document Server

    Belhaj, A; Moumni, H EL; Masmar, K; Sedra, M B

    2015-01-01

    Motivated by a recent work on asymptotically AdS_4 black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2 and M5-branes. Concretely, we consider AdS black holes in AdS_{p+2}\\times S^{11-p-2}, where p=2,5 by interpreting the number of M2 (and M5-branes) as a thermodynamical variable. We study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then, we compute the thermodynamical curvatures from the Quevedo metric for M2 and M5-branes geometries to reconsider the stability of such black objects. The Quevedo metric singularities recover similar stability results provided by the phase transition program.

  13. Quality Characteristics of Stirred Yoghurt Added with Fermented Red Pepper.

    Science.gov (United States)

    Yu, Mi-Sang; Kim, Jeong-Mee; Lee, Chi-Ho; Son, Yoon-Jeong; Kim, Soo-Ki

    2014-01-01

    Pungency of hot pepper has limited its usage even though it shows various health beneficial effects. This study was conducted to develop the novel yoghurt containing hot pepper with diminishing pungency and aimed to examine the quality characteristics of yoghurt prepared with fermented red pepper. Hot pepper was first fermented with Bacillus licheniformis SK1230 to reduce the pungency of capsaicin. We then examined the quality, sensory characteristics, and antioxidant activity of yoghurt containing the fermented red pepper. The titratable acidity of this yoghurt increased whereas the viscosity decreased with increasing amounts of added red pepper. The total polyphenol content increased in proportion to the amount of added red pepper. The antioxidant activity significantly increased with the addition of red pepper (p<0.05). Color evaluation showed that the L value decreased whereas the a and b values increased significantly with the amount of red pepper added (p<0.05). In the sensory evaluation, yoghurt prepared with higher amounts of fermented red pepper received lower scores. However, yoghurt containing fermented red pepper at a concentration of 0.05% received higher scores for taste, flavor, and overall acceptability than yoghurt prepared with non-fermented pepper. Therefore, it can be concluded that the application of red pepper fermented by Bacillus licheniformis SK1230 gives beneficial feature to the preparation of yoghurt.

  14. Presence of non-fibrillar amyloid beta protein in skin biopsies of Alzheimer's disease (AD), Down's syndrome and non-AD normal persons

    DEFF Research Database (Denmark)

    Wen, G Y; Wisniewski, H M; Blondal, H;

    1994-01-01

    A total of 66 skin biopsies from persons with Alzheimer's disease (AD) or Down's syndrome (DS) and from persons without AD were used in this study. The age range was from 7 to 89 years. Positive immunoreactivity of skin biopsies to monoclonal antibody 4G8, which is reactive to amino acid residue 17....../38 (37%) non-AD control cases. The Fisher exact probability test revealed a significant difference (P = 0.0415 one-tailed) in immunoreactivity between AD and age-matched controls. There was also a significant difference (P = 0.0152 one-tailed; P = 0.0200 two-tailed) between DS and age-matched control...

  15. CHOICE OF EFFICIENT METHOD OF ADDING FLOUR FROM BUCKWHEAT BRAN

    Directory of Open Access Journals (Sweden)

    E. I. Ponomareva

    2015-01-01

    Full Text Available Nowadays the production of functional bakery products for therapeutic and preventive nutrition is of current importance. The problem of providing the population with functional products can be solved by enriching the recipes with vitamins, dietary fiber, micro and macronutrients. At the chair of "Technology of baking, confectionery, pasta and grain processing" of Voronezh State University of Engineering Technologies the recipe of no-salt bread from mixture of baker’s first grade wheat flour and whole-grain wheat with adding buckwheat bran flour, that increases the nutrition value of the product, has been developed. Flour from buckwheat bran is characterized by a high-scale balance of the content of essential amino acids, good digestibility, rich in vitamins (especially B vitamins, PP, dietary fiber, minerals (potassium, calcium, magnesium, iron. The use of buckwheat flour from the bran in bread production stimulates the creation of favorable intestinal microflora, normalizes blood sugar level, and excretes toxins, toxic salts and heavy metals from the body. We have conducted a research on how to make the rational choice of method of adding buckwheat bran flour enricher into dough from a mixture of first grade wheat flour and whole-grain wheat, compressed yeast and potable water, thus ensuring high and stable physical and chemical characteristics and the quality of the end product. Also, we have discovered that the bakery product prepared on tight sponge with addition of enricher has much better organoleptical properties in comparison with the others. Bread is characterized by a pleasant taste and flavour, elastic porous crumb. It has been found that the consumption of 100 g of a mixture of no-salt bread from first grade wheat flour and whole-grain with adding buckwheat bran flour will provide enough daily intake of protein 10.7%, fat 1.5%, carbohydrates 10.4% dietary fiber 16.3%, amino acids 2.5 14.0%. No-salt bread is recommended to people

  16. Higher spin contributions to holographic fluid dynamics in AdS5/CFT4

    Science.gov (United States)

    Lee, Seungjin; Polyakov, Dimitri

    2014-08-01

    We calculate the graviton's β function in the AdS string-theoretic sigma model, perturbed by vertex operators for Vasiliev's higher spin gauge fields in AdS5. The result is given by βmn=Rmn+4Tmn(g ,u) (with the AdS radius set to 1 and the graviton polarized along the AdS5 boundary), with the matter stress-energy tensor given by that of conformal holographic fluid in d =4, evaluated at the temperature given by T =1/π. The stress-energy tensor is given by Tmn=gmn+4umun+∑NTmn(N) where u is the vector excitation satisfying u2=-1 and N is the order of the gradient expansion in the dissipative part of the tensor. We calculate the contributions up to N =2. The higher spin excitations contribute to the β function, ensuring the overall Weyl covariance of the matter stress tensor. We conjecture that the structure of gradient expansion in d =4 conformal hydrodynamics at higher orders is controlled by the higher spin operator algebra in AdS5.

  17. Interpolating from Bianchi Attractors to Lifshitz and AdS Spacetimes

    CERN Document Server

    Kachru, Shamit; Saha, Arpan; Samanta, Rickmoy; Trivedi, Sandip P

    2013-01-01

    We construct classes of smooth metrics which interpolate from Bianchi attractor geometries of Types II, III, VI and IX in the IR to Lifshitz or $AdS_2 \\times S^3$ geometries in the UV. While we do not obtain these metrics as solutions of Einstein gravity coupled to a simple matter field theory, we show that the matter sector stress-energy required to support these geometries (via the Einstein equations) does satisfy the weak, and therefore also the null, energy condition. Since Lifshitz or $AdS_2 \\times S^3$ geometries can in turn be connected to $AdS_5$ spacetime, our results show that there is no barrier, at least at the level of the energy conditions, for solutions to arise connecting these Bianchi attractor geometries to $AdS_5$ spacetime. The asymptotic $AdS_5$ spacetime has no non-normalizable metric deformation turned on, which suggests that furthermore, the Bianchi attractor geometries can be the IR geometries dual to field theories living in flat space, with the breaking of symmetries being either sp...

  18. Closed string tachyons on AdS orbifolds and dual Yang-Mills instantons

    Energy Technology Data Exchange (ETDEWEB)

    Hikida, Y. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Iizuka, N. [California Univ., Santa Barbara, CA (United States). Kavli Inst. for Theoretical Physics

    2007-06-15

    We study the condensation of localized closed string tachyons on AdS orbifolds both from the bulk and boundary theory viewpoints. We first extend the known results for AdS{sub 5}/Z{sub k} to AdS{sub 3}/Z{sub k} case, and we proposed that the AdS{sub 3}/Z{sub k} decays into AdS{sub 3}/Z{sub k'} with k{sup '} < k. From the bulk viewpoint, we obtain a time-dependent gravity solution describing the decay of AdS orbifold numerically. From the dual gauge theory viewpoint, we calculated the Casimir energies of gauge theory vacua and it is found that their values are exactly the same as the masses of dual geometries, even though they are in different parameter regimes of 't Hooft coupling. We also consider AdS{sub 5} orbifold. The decay of AdS{sub 5}/Z{sub k} is dual to the transition between the vacua of dual gauge theory on R{sub t} x S{sup 3}/Z{sub k}. We constructed the instanton solutions describing the transitions by making use of instanton solutions on R{sub t} x S{sup 2}. (orig.)

  19. Implementation of Recursion Relations in Gluon Scattering Amplitude Calculations in AdS4 /CFT3

    Science.gov (United States)

    Dokmetzoglou, Nikolaos; Kharel, Savan

    2017-01-01

    The Anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence is a duality between a theory of gravity in curved-space (AdS) and a conformally-invariant quantum field theory in flat-space (CFT). Scattering amplitudes are observables associated with the probability of the interaction of a given assembly of particles. Gluons, being the exchange particles associated with the strong nuclear force, which holds quarks together to form protons, are abundant byproducts of fundamental particle collisions. Thus, studying gluon scattering amplitudes is an effective way of deepening our understanding of these observables in AdS/CFT. Traditionally, Feynman diagrams have been used to calculate such scattering amplitudes. In this project, we use factorization properties and recursion relations to simplify these calculations. More specifically, we calculate multiple (different helicity combinations) four-point gluon scattering amplitudes in AdS4 /CFT3 (4-D AdS and 3-D CFT) as sums of products of three-point amplitudes. And then we calculate a five-point gluon scattering amplitude in AdS4 /CFT3 by decomposing it into a sum of products of these four-point and three-point amplitudes. Finally we comment on useful identities for checking these amplitudes. This work was supported by a Weinstein Davidson College Research Initiative Summer Research grant.

  20. Extended supersymmetric sigma models in AdS_4 from projective superspace

    CERN Document Server

    Butter, Daniel; Lindstrom, Ulf; Tartaglino-Mazzucchelli, Gabriele

    2012-01-01

    There exist two superspace approaches to describe N=2 supersymmetric nonlinear sigma models in four-dimensional anti-de Sitter (AdS_4) space: (i) in terms of N=1 AdS chiral superfields, as developed in arXiv:1105.3111 and arXiv:1108.5290; and (ii) in terms of N=2 polar supermultiplets using the AdS projective-superspace techniques developed in arXiv:0807.3368. The virtue of the approach (i) is that it makes manifest the geometric properties of the N=2 supersymmetric sigma-models in AdS_4. The target space must be a non-compact hyperkahler manifold endowed with a Killing vector field which generates an SO(2) group of rotations on the two-sphere of complex structures. The power of the approach (ii) is that it allows us, in principle, to generate hyperkahler metrics as well as to address the problem of deformations of such metrics. Here we show how to relate the formulation (ii) to (i) by integrating out an infinite number of N=1 AdS auxiliary superfields and performing a superfield duality transformation. We al...

  1. AdS and Lifshitz scalar hairy black holes in Gauss-Bonnet gravity

    Science.gov (United States)

    Chen, Bin; Fan, Zhong-Ying; Zhu, Lu-Yao

    2016-09-01

    We consider Gauss-Bonnet (GB) gravity in general dimensions, which is nonminimally coupled to a scalar field. By choosing a scalar potential of the type V (ϕ )=2 Λ0+1/2 m2ϕ2+γ4ϕ4 , we first obtain large classes of scalar hairy black holes with spherical/hyperbolic/planar topologies that are asymptotic to locally anti- de Sitter (AdS) space-times. We derive the first law of black hole thermodynamics using Wald formalism. In particular, for one class of the solutions, the scalar hair forms a thermodynamic conjugate with the graviton and nontrivially contributes to the thermodynamical first law. We observe that except for one class of the planar black holes, all these solutions are constructed at the critical point of GB gravity where there exist unique AdS vacua. In fact, a Lifshitz vacuum is also allowed at the critical point. We then construct many new classes of neutral and charged Lifshitz black hole solutions for an either minimally or nonminimally coupled scalar and derive the thermodynamical first laws. We also obtain new classes of exact dynamical AdS and Lifshitz solutions which describe radiating white holes. The solutions eventually become AdS or Lifshitz vacua at late retarded times. However, for one class of the solutions, the final state is an AdS space-time with a globally naked singularity.

  2. The Impact of Ad Characteristics on Adolescents’ Attitudes Towards Antismoking Ads

    Directory of Open Access Journals (Sweden)

    Domen Bajde

    2008-03-01

    Full Text Available Smoking exerts a considerable burden not only on those who smoke but just as well on society at large. In response, governments and institutions often resort to advertising which aims to discourage smoking. Unfortunately, our knowledge of the workings of antismoking advertising is detrimentally limited. In particular, the literature delving into the impact of antismoking ad characteristics (e. g., ad content, valence, intensity on the overall effectiveness of antismoking advertising is scarce and contradictory. This empirical study aims to enhance the knowledge of antismoking advertising by presenting results of the survey involving Slovene adolescents. The adolescents were first exposed to advertisements of different antismoking ad contents (for the purpose of this study the term ‘ad content’ refers to types of appeals used in antismoking advertising, ad valence and intensity, and later invited to respond to a number of questions measuring their attitudes toward the ads, their attitudes toward smoking, their intentions to smoke, etc. The results indicate that while the different intensity and valence of ads produce varying attitudes toward the ads, we could not confirm these differences based on ad content. Also, we found that adolescent smokers respond to antismoking ads differently than do their nonsmoking peers. Our findings offer several important implications for antismoking advertisers and the research community interested in the workings of antismoking advertising.

  3. On the Thermodynamic Geometry and Critical Phenomena of AdS Black Holes

    CERN Document Server

    Sahay, Anurag; Sengupta, Gautam

    2010-01-01

    In this paper, we study various aspects of the equilibrium thermodynamic state space geometry of AdS black holes. We first examine the Reissner-Nordstrom-AdS (RN-AdS) and the Kerr-AdS black holes. In this context, the state space scalar curvature of these black holes are analysed in various regions of their thermodynamic parameter space. This provides important new insights into the structure and significance of the scalar curvature. We further investigate critical phenomena, and the behaviour of the scalar curvature near criticality, for KN-AdS black holes in two mixed ensembles, introduced and elucidated in our earlier work arXiv:1002.2538 [hep-th]. The critical exponents are identical to those in the RN-AdS and Kerr-AdS cases in the canonical ensemble. This suggests an universality in the scaling behaviour near critical points of AdS black holes. Our results further highlight qualitative differences in the thermodynamic state space geometry for electric charge and angular momentum fluctuations of these.

  4. Comment on "AdS nonlinear instability: moving beyond spherical symmetry" [Class. Quantum Grav. 33 23LT01 (2016)

    CERN Document Server

    Rostworowski, Andrzej

    2016-01-01

    We argue that if the degeneracy of the spectrum of linear perturbations of AdS is properly taken into account, there are globally regular, time-periodic, asymptotically AdS solutions (geons) bifurcating from each linear eigenfrequency of AdS.

  5. Brick walls and AdS/CFT

    Science.gov (United States)

    Kay, Bernard S.; Ortíz, L.

    2014-05-01

    We discuss the relationship between the bulk-boundary correspondence in Rehren's algebraic holography (and in other `fixed-background', QFT-based, approaches to holography) and in mainstream string-theoretic `Maldacena AdS/CFT'. Especially, we contrast the understanding of black-hole entropy from the point of view of QFT in curved spacetime—in the framework of 't Hooft's `brick wall' model—with the understanding based on Maldacena AdS/CFT. We show that the brick-wall modification of a Klein-Gordon field in the Hartle-Hawking-Israel state on dimensional Schwarzschild AdS has a well-defined boundary limit with the same temperature and entropy as the brick-wall-modified bulk theory. One of our main purposes is to point out a close connection, for general AdS/CFT situations, between the puzzle raised by Arnsdorf and Smolin regarding the relationship between Rehren's algebraic holography and mainstream AdS/CFT and the puzzle embodied in the `complementarity principle' proposed by Mukohyama and Israel in their work on the brick-wall approach to black hole entropy. Working on the assumption that similar results will hold for bulk QFT other than the Klein-Gordon field and for Schwarzschild AdS in other dimensions, and recalling the first author's proposed resolution to the Mukohyama-Israel puzzle based on his `matter-gravity entanglement hypothesis', we argue that, in Maldacena AdS/CFT, the algebra of the boundary CFT is isomorphic only to a proper subalgebra of the bulk algebra, albeit (at non-zero temperature) the (GNS) Hilbert spaces of bulk and boundary theories are still the `same'—the total bulk state being pure, while the boundary state is mixed (thermal). We also argue from the finiteness of its boundary (and hence, on our assumptions, also bulk) entropy at finite temperature, that the Rehren dual of the Maldacena boundary CFT cannot itself be a QFT and must, instead, presumably be something like a string theory.

  6. Ad Hoc Access Gateway Selection Algorithm

    Science.gov (United States)

    Jie, Liu

    With the continuous development of mobile communication technology, Ad Hoc access network has become a hot research, Ad Hoc access network nodes can be used to expand capacity of multi-hop communication range of mobile communication system, even business adjacent to the community, improve edge data rates. For mobile nodes in Ad Hoc network to internet, internet communications in the peer nodes must be achieved through the gateway. Therefore, the key Ad Hoc Access Networks will focus on the discovery gateway, as well as gateway selection in the case of multi-gateway and handover problems between different gateways. This paper considers the mobile node and the gateway, based on the average number of hops from an average access time and the stability of routes, improved gateway selection algorithm were proposed. An improved gateway selection algorithm, which mainly considers the algorithm can improve the access time of Ad Hoc nodes and the continuity of communication between the gateways, were proposed. This can improve the quality of communication across the network.

  7. Higher spin holography and the AdS string sigma model

    Science.gov (United States)

    Polyakov, Dimitri

    2013-05-01

    We analyse the cubic spin-3 interaction in AdS space using the higher spin extension of the string-theoretic sigma-model constructed in our previous work, whose low energy limit is described by the AdS vacuum solution. We find that, in the leading order of the cosmological constant, the spin-3 correlator on the AdS4 string theory side reproduces the structure of the three-point function of composite operators, quadratic in free fields, in the dual d = 3 vector model. The cancellation of holography violating terms in d = 3 is related to the value of the Liouville background charge in d = 4. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Higher spin theories and holography’.

  8. Vacuum type space-like string surfaces in AdS_3 x S^3

    CERN Document Server

    Dorn, Harald; Kalousios, Chrysostomos; Megrelidze, Luka; Wuttke, Sebastian

    2010-01-01

    We construct and classify all space-like minimal surfaces in AdS_3 x S^3 which globally admit coordinates with constant induced metric on both factors. Up to O(2,2) x O(4) transformations all these surfaces, except one class, are parameterized by four real parameters. The classes of surfaces correspond to different regions in this parameter space and show quite different boundary behavior. Our analysis uses a direct construction of the string coordinates via a group theoretical treatment based on the map of AdS_3 x S^3 to SL(2,R) x SU(2). This is complemented by a cross check via standard Pohlmeyer reduction. After embedding in AdS_5 x S^5 we calculate the regularized area for solutions with a boundary spanned by a four point scattering s-channel momenta configuration.

  9. A note on vectorial AdS5/CFT4 duality for spin- j boundary theory

    Science.gov (United States)

    Bae, Jin-Beom; Joung, Euihun; Lal, Shailesh

    2016-12-01

    The vectorial holographic correspondences between higher-spin theories in AdS5 and free vector models on the boundary are extended to the cases where the latter is described by free massless spin- j field. The dual higher-spin theory in the bulk does not include gravity and can only be defined on rigid AdS5 background with S 4 boundary. We discuss various properties of these rather special higher-spin theories and calculate their one-loop free energies. We show that the result is proportional to the same quantity for spin- j doubleton treated as if it is a AdS5 field. Finally, we consider even more special case where the boundary theory itself is given by an infinite tower of massless higher-spin fields.

  10. Vacuum energy in Einstein-Gauss-Bonnet AdS gravity

    CERN Document Server

    Kofinas, G; Kofinas, Georgios; Olea, Rodrigo

    2006-01-01

    A finite action principle for Einstein-Gauss-Bonnet AdS gravity is presented. The boundary term, which is different for even and odd dimensions, is a functional of the boundary metric, intrinsic curvature and extrinsic curvature. For even dimensions, the boundary term corresponds to the maximal Chern form of the spacetime, and the asymptotic AdS condition for the curvature suffices for the well-posedness of this action. For odd dimensions, the action is stationary under a boundary condition on the variation of the extrinsic curvature. The background-independent Noether charges associated to asymptotic symmetries are found and the Euclidean continuation of the action correctly describes the black hole thermodynamics in the canonical ensemble. In particular, this procedure leads to a covariant formula for the vacuum energy in odd-dimensional asymptotically AdS spacetimes.

  11. A Stochasticity Threshold in Holography and and the Instability of AdS

    CERN Document Server

    Basu, Pallab; Saurabh, Ayush

    2014-01-01

    We give strong numerical evidence that a self-interacting probe scalar field in AdS, with only a few modes turned on initially, will undergo fast thermalization only if it is above a certain energetic threshold. Below the threshold the energy stays close to constant in a few modes for a very long time instead of cascading quickly. This indicates the existance of a Strong Stochasticity Threshold (SST) in holography. The idea of SST is familiar from certain statistical mechanical systems, and we suggest that it exists also in AdS gravity. This would naturally reconcile the generic non-linear instability of AdS observed by Bizon and Rostworowski, with the Fermi-Pasta-Ulam-Tsingou-like quasi-periodocity noticed recently for some classes of initial conditions. We show that our simple set-up captures many of the relevant features of the full gravity-scalar system.

  12. Banados and SUSY: On Supersymmetry and Minimal Surfaces of Locally AdS3 Geometries

    CERN Document Server

    Colgáin, E Ó

    2016-01-01

    We extend the classification of supersymmetric locally AdS$_3$ geometries, beyond BTZ black holes, to the Ba\\~nados geometries, noting that supersymmetries are in one-to-one correspondence with solutions to the Hill differential condition. We show that the number of global supersymmetries is an orbit invariant quantity and identify geometries with zero, one, two, three and four global supersymmetries. As an application of our classification, we exploit supersymmetry, which is preserved locally in the bulk, to determine space-like co-dimension two surfaces in AdS$_3$. In the process, we by-pass geodesics or mappings of AdS$_3$, neither of which have an analogue in higher dimensions, to recover known Hubeny-Rangamani-Takayanagi surfaces. Our findings suggest supersymmetry can be exploited to find extremal surfaces in holographic entanglement entropy.

  13. Quark confinement due to creation of micro AdS black holes in quarkonium model

    CERN Document Server

    Taki, Mehran

    2016-01-01

    We use the solution of the Dirac equation for quarkonium atom in the 4D Anti de sitter (AdS$_{4}$) space to investigate the effect of the large negative cosmological constant on the phenomenon of quark confinement. We do the required calculations in the AdS$_{4}$ space to indicate that large cosmological constant can describe the quark confinement. In fact using the coulomb potential in Dirac equation while we employ the AdS metric will additionally lead us to a linear potential in the quark-antiquark interaction which can be considered to explain the quark confinement. This confining term is arising essentially from the geometrical features of the space. On the other hand the origin of the large cosmological constant can be justified by assuming the appearance of micro black holes in the recent hadronic collision process which is now current, for instance, at the LHC project.

  14. QCD condensates and holographic Wilson loops for asymptotically AdS spaces

    Science.gov (United States)

    Quevedo, R. Carcasses; Goity, J. L.; Trinchero, R. C.

    2014-02-01

    The minimization of the Nambu-Goto action for a surface whose contour defines a circular Wilson loop of radius a placed at a finite value of the coordinate orthogonal to the boundary is considered. This is done for asymptotically anti-de Sitter (AdS) spaces. The condensates of even dimension n =2 through 10 are calculated in terms of the coefficient of an in the expansion of the on-shell subtracted Nambu-Goto action for small a. The subtraction employed is such that it presents no conflict with conformal invariance in the AdS case and need not introduce an additional infrared scale for the case of confining geometries. It is shown that the UV value of the condensates is universal in the sense that they only depend on the first coefficients of the difference with the AdS case.

  15. Photon gas thermodynamics in dS and AdS momentum spaces

    CERN Document Server

    Gorji, M A; Nozari, K; Vakili, B

    2016-01-01

    In this paper, we study thermostatistical properties of a photon gas in the framework of two deformed special relativity models defined by the cosmological coordinatizations of the de Sitter (dS) and anti-de Sitter (AdS) momentum spaces. The dS model is a doubly special relativity theory in which an ultraviolet length scale is invariant under the deformed Lorentz transformations. For the case of AdS model, however, the Lorentz symmetry breaks at the high energy regime. We show that the existence of a maximal momentum in dS momentum space leads to maximal pressure and temperature at the thermodynamical level while maximal internal energy and entropy arise for the case of the AdS momentum space due to the existence of a maximal kinematical energy. These results show the thermodynamical duality of these models much similar to their well-known kinematical duality.

  16. On thermodynamics of AdS black holes in M-theory

    Energy Technology Data Exchange (ETDEWEB)

    Belhaj, A. [Universite Sultan Moulay Slimane, Departement de Physique, LIRST, Faculte Polydisciplinaire, Beni Mellal (Morocco); Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Chabab, M.; Masmar, K. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); El Moumni, H. [Cadi Ayyad University, High Energy Physics and Astrophysics Laboratory, FSSM, Marrakesh (Morocco); Universite Ibn Zohr, Departement de Physique, Faculte des Sciences, Agadir (Morocco); Sedra, M.B. [Universite Ibn Tofail, Departement de Physique, LASIMO, Faculte des Sciences, Kenitra (Morocco)

    2016-02-15

    Motivated by recent work on asymptotically AdS{sub 4} black holes in M-theory, we investigate the thermodynamics and thermodynamical geometry of AdS black holes from M2- and M5-branes. Concretely, we consider AdS black holes in AdS{sub p+2} x S{sup 11-p-2}, where p = 2,5 by interpreting the number of M2- (and M5-branes) as a thermodynamical variable. More precisely, we study the corresponding phase transition to examine their stabilities by calculating and discussing various thermodynamical quantities including the chemical potential. Then we compute the thermodynamical curvatures from the Quevedo metric for M2- and M5-branes geometries to reconsider the stability of such black holes. The Quevedo metric singularities recover similar stability results provided by the phase-transition program. It has been shown that similar behaviors are also present in the limit of large N. (orig.)

  17. Thermal stability analysis of nonlinearly charged asymptotic AdS black hole solutions

    Science.gov (United States)

    Dehghani, M.; Hamidi, S. F.

    2017-08-01

    In this paper, the four-dimensional nonlinearly charged black hole solutions have been considered in the presence of the power Maxwell invariant electrodynamics. Two new classes of anti-de Sitter (AdS) black hole solutions have been introduced according to different amounts of the parameters in the nonlinear theory of electrodynamics. The conserved and thermodynamical quantities of either of the black hole classes have been calculated from geometrical and thermodynamical approaches, separately. It has been shown that the first law of black hole thermodynamics is satisfied for either of the AdS black hole solutions we just obtained. Through the canonical and grand canonical ensemble methods, the black hole thermal stability or phase transitions have been analyzed by considering the heat capacities with the fixed black hole charge and fixed electric potential, respectively. It has been found that the new AdS black holes are stable if some simple conditions are satisfied.

  18. QCD Condensates and Holographic Wilson Loops for Asymptotically AdS Spaces

    Energy Technology Data Exchange (ETDEWEB)

    Quevedo, R. Carcasses [Instituto Balseiro, Centro Atomico Bariloche, 8400 San Carlos de Bariloche (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina); Goity, Jose L. [Hampton University, Hampton, VA 23668 (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Trinchero, Roberto C. [Instituto Balseiro, Centro Atomico Bariloche, 8400 San Carlos de Bariloche (Argentina); CONICET, Rivadavia 1917, 1033 Buenos Aires (Argentina)

    2014-02-01

    The minimization of the Nambu-Goto (NG) action for a surface whose contour defines a circular Wilson loop of radius a placed at a finite value of the coordinate orthogonal to the border is considered. This is done for asymptotically AdS spaces. The condensates of dimension n = 2, 4, 6, 8, and 10 are calculated in terms of the coefficients in the expansion in powers of the radius a of the on-shell subtracted NG action for small a->0. The subtraction employed is such that it presents no conflict with conformal invariance in the AdS case and need not introduce an additional infrared scale for the case of confining geometries. It is shown that the UV value of the gluon condensates is universal in the sense that it only depends on the first coefficients of the difference with the AdS case.

  19. Sensorial, biochemical and microbiological evaluations of guacamole, an avocado based product, under cold storage and added with ascorbic acidAvaliações sensoriais, bioquímicas e microbiológicas do guacamole, um produto à base de abacate, sob armazenamento a frio e com adição de ácido ascórbico

    Directory of Open Access Journals (Sweden)

    Lídia Raquel de Carvalho

    2011-07-01

    Full Text Available The elaboration of avocado products for commercialization keeping their characteristics of fresh product has been limited. The cut avocado darkens quickly and their sensorial characteristics are modified with the storage. In the present research, the sensorial parameters, microbiological stability, and peroxidase and polyphenoloxidase activity were evaluated in guacamole added with ascorbic acid and conserved under low temperature, by using avocado variety Hass. Products were conditioned in polyethylene+nylon packages with and without vacuum application; then, they were subjected to the slow and fast freezing (-18ºC and stored in freezer (-18ºC. Evaluations were performed at the moment of elaboration of the product (t0 and at 3, 7 and 30 days post-storage. At t30, samples were kept under refrigeration (4 ±1oC and evaluated at 3, 5 and 7 days. After the 30 days of storage, –18 ºC under freezing, followed by thawing and keeping at 4±1ºC for 7 days, the notes for the sensorial parameters decreased. The peroxidase activity was totally inhibited in the elaborated product and the polifenol oxidase activity considerably decreased in the guacamole (20.07 mM catechol/g fresh matter relative to those in the fruit (58.31 mM catechol/g fresh matter, however with no significant variation during storage (at -18ºC. The samples were microbiologically stable under the conditions of the present study. The addition of ascorbic acid contributed to the conservation of the frozen avocado product by decreasing the enzymatic activity. However, the sensorial parameters are prejudiced under thawing and storage at 4 ±1oC.A elaboração de produtos de abacate para comercialização mantendo suas características de produto fresco é limitada, já que o fruto cortado escurece rapidamente e suas características sensoriais são modificadas com o armazenamento. Na presente pesquisa, avaliaram-se os parâmetros sensoriais, estabilidade microbiológica e atividade de

  20. The Synthesis of Multiple Polyaspartic Acid Water Treatment Agent and Study on Scale Inhibitor Performance of Calcium Carbonate%多元聚天冬氨酸水处理剂的合成及阻碳酸钙垢性能研究

    Institute of Scientific and Technical Information of China (English)

    杨玉华; 徐建宝; 王小龙; 苟振中

    2013-01-01

    以马来酸酐和碳酸铵为原料,热缩制备了绿色阻垢剂聚天冬氨酸(PASP),并用红外光谱对聚合物进行了表征.研制了一种无磷多元的绿色阻垢剂,其组成为聚天冬氨酸(PASP)、单宁酸(Tanic acid)和葡萄糖酸钠(Sodium gluconate).通过正交试验确定了该复合药剂的最佳配比.通过碳酸钙沉积法对PASP及其复合产品的阻垢性能进行了对比.结果表明:与PASP、Tanic acid或Sodium gluconate中的任意一种单剂以及PASP与Tanic acid或Sodium gluconate的二元复合水处理剂相比,PASP的三元复合水处理剂具有很好的阻碳酸钙垢的效果.当质量比,m(PASP)∶m(Tanic acid)∶m(Sodium gluconate)=1∶2∶3,总加量为24 mg·L-1时,阻垢率可达99.4%.实验结果为聚天冬氨酸的工业应用提供了参考价值.%As a green scale inhibitor,polyaspartic acid (PASP) was synthesized by thermal polymerization processes of maleic anhydride and ammonium carbonate and was characterized by means of infrared spectrometry (IR).A kind of green scale inhibitor was developed,and the main composition included PASP,tannic acid and sodium glucorote.The best ratio of this product was determined by orthogonal experiment.Scale inhibition performance of PASP and its compound products was compared by scale inhibition method against CaCO3.The results indicated that compared with single agent and the binary compound water treatment agent which was prepared by PASP with tannic acid or sodium gluconate,an excellent scale inhibitor against CaCO3 was obtained by ternary compound water treatment agent of PASP.When the mars ratio was m(PASP) ∶m(Tannic acid) ∶m(Sodium gluconate)=1∶2∶3,the scale inhibition rate can almost reach to 99.4%,and the total concentration was 24mg/L.The experimental results provided a valuable reference for industrial application of polyaspartic acid.

  1. Wireless Ad Hoc Networks%无线特定网络--Ad Hoc网络

    Institute of Scientific and Technical Information of China (English)

    张筱; 张光昭

    2001-01-01

    Ad Hoc网络是一种没有固定结构的无线移动网络.介绍了移动Ad Hoc网络(MANETs)的主要特点和与传统有线分组交换网相比的特性,讨论了应用于Ad Hoc网络的路由机制和所需面临的问题.

  2. Secure Clustering in Vehicular Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Zainab Nayyar

    2015-09-01

    Full Text Available A vehicular Ad-hoc network is composed of moving cars as nodes without any infrastructure. Nodes self-organize to form a network over radio links. Security issues are commonly observed in vehicular ad hoc networks; like authentication and authorization issues. Secure Clustering plays a significant role in VANETs. In recent years, various secure clustering techniques with distinguishing feature have been newly proposed. In order to provide a comprehensive understanding of these techniques are designed for VANETs and pave the way for the further research, a survey of the secure clustering techniques is discussed in detail in this paper. Qualitatively, as a result of highlighting various techniques of secure clustering certain conclusions are drawn which will enhance the availability and security of vehicular ad hoc networks. Nodes present in the clusters will work more efficiently and the message passing within the nodes will also get more authenticated from the cluster heads.

  3. Introduction to AdS/CFT correspondence

    CERN Document Server

    Nastase, Horatiu

    2015-01-01

    Providing a pedagogical introduction to the rapidly developing field of AdS/CFT correspondence, this is one of the first texts to provide an accessible introduction to all the necessary concepts needed to engage with the methods, tools and applications of AdS/CFT. Without assuming anything beyond an introductory course in quantum field theory, it begins by guiding the reader through the basic concepts of field theory and gauge theory, general relativity, supersymmetry, supergravity, string theory and conformal field theory, before moving on to give a clear and rigorous account of AdS/CFT correspondence. The final section discusses the more specialised applications, including QCD, quark-gluon plasma and condensed matter. This book is self-contained and learner-focused, featuring numerous exercises and examples. It is essential reading for both students and researchers across the fields of particle, nuclear and condensed matter physics.

  4. Online Stochastic Ad Allocation: Efficiency and Fairness

    CERN Document Server

    Feldman, Jon; Korula, Nitish; Mirrokni, Vahab S; Stein, Cliff

    2010-01-01

    We study the efficiency and fairness of online stochastic display ad allocation algorithms from a theoretical and practical standpoint. In particular, we study the problem of maximizing efficiency in the presence of stochastic information. In this setting, each advertiser has a maximum demand for impressions of display ads that will arrive online. In our model, inspired by the concept of free disposal in economics, we assume that impressions that are given to an advertiser above her demand are given to her for free. Our main theoretical result is to present a training-based algorithm that achieves a (1-\\epsilon)-approximation guarantee in the random order stochastic model. In the corresponding online matching problem, we learn a dual variable for each advertiser, based on data obtained from a sample of impressions. We also discuss different fairness measures in online ad allocation, based on comparison to an ideal offline fair solution, and develop algorithms to compute "fair" allocations. We then discuss sev...

  5. Data Confidentiality in Mobile Ad hoc Networks

    CERN Document Server

    Aldabbas, Hamza; Janicke, Helge; Al-Bayatti, Ali; 10.5121/ijwmn.2012.4117

    2012-01-01

    Mobile ad hoc networks (MANETs) are self-configuring infrastructure-less networks comprised of mobile nodes that communicate over wireless links without any central control on a peer-to-peer basis. These individual nodes act as routers to forward both their own data and also their neighbours' data by sending and receiving packets to and from other nodes in the network. The relatively easy configuration and the quick deployment make ad hoc networks suitable the emergency situations (such as human or natural disasters) and for military units in enemy territory. Securing data dissemination between these nodes in such networks, however, is a very challenging task. Exposing such information to anyone else other than the intended nodes could cause a privacy and confidentiality breach, particularly in military scenarios. In this paper we present a novel framework to enhance the privacy and data confidentiality in mobile ad hoc networks by attaching the originator policies to the messages as they are sent between nod...

  6. Rotating Rindler-AdS space

    Science.gov (United States)

    Parikh, Maulik; Samantray, Prasant; Verlinde, Erik

    2012-07-01

    If the Hamiltonian of a quantum field theory is taken to be a timelike isometry, the vacuum state remains empty for all time. We search for such stationary vacua in anti-de Sitter space. By considering conjugacy classes of the Lorentz group, we find interesting one-parameter families of stationary vacua in three-dimensional anti-de Sitter space. In particular, there exists a family of rotating Rindler vacua, labeled by the rotation parameter β, which are related to the usual Rindler vacuum by nontrivial Bogolubov transformations. Rotating Rindler-AdS space possesses not only an observer-dependent event horizon but even an observer-dependent ergosphere. We also find rotating vacua in global AdS provided a certain region of spacetime is excluded.

  7. Rotating Rindler-AdS Space

    CERN Document Server

    Parikh, Maulik; Verlinde, Erik

    2011-01-01

    If the Hamiltonian of a quantum field theory is taken to be a timelike isometry, the vacuum state remains empty for all time. We search for such stationary vacua in anti-de Sitter space. By considering conjugacy classes of the Lorentz group, we find interesting one-parameter families of stationary vacua in three-dimensional anti-de Sitter space. In particular, there exists a family of rotating Rindler vacua, labeled by the rotation parameter beta, which are related to the usual Rindler vacuum by non-trivial Bogolubov transformations. Rotating Rindler-AdS space possesses not only an observer-dependent event horizon but even an observer-dependent ergosphere. We also find rotating vacua in global AdS provided a certain region of spacetime is excluded.

  8. AD Ejection Line Studies and Optics Improvements

    CERN Document Server

    Belochitskii, P

    2013-01-01

    This paper is a summary of the work we made to understand and improve the AD ejection line optics. In 2011 significant differences were noticed between the optical properties of the AD ejection line and the MAD model. Investigations started to find out the sources of discrepancy. Better understanding of the ejection line optics was obtained and corrections were applied to the model of ejection line. The beam delivery to the experiments is better understood now. The results obtained might be useful as well for the optics design of AD to ELENA transfer line. Potential problems with the fringing field model in MAD were pointed out, when bending magnets with large bending angles and small bending radius are involved.

  9. New Features in the ADS Abstract Service

    Science.gov (United States)

    Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Kurtz, M. J.; ReyBacaicoa, V.; Murray, S. S.

    2001-11-01

    The ADS Abstract Service contains over 2.3 million references in four databases: Astronomy/Astrophysics/Planetary Sciences, Instrumentation, Physics/Geophysics, and Preprints. We provide abstracts and articles free to the astronomical community for all major and many smaller astronomy journals, PhD theses, conference proceedings, and technical reports. These four databases can be queried either separately of jointly. The ADS also has scanned 1.3 million pages in 180,000 articles in the ADS Article Service. This literature archive contains all major Astronomy journals and many smaller journals, as well as conference proceedings, including the abstract books from all the LPSCs back to volume 2. A new feature gives our users the ability to see list of articles that were also read by the readers of a given article. This is a powerful tool to find out what current articles are relevant in a particular field of study. We have recently expanded the citation and reference query capabilities. It allows our users to select papers for which they want to see references or citations and then retrieve these citations/references. Another new capability is the ability to sort a list of articles by their citation count. As usual, users should be reminded that the citations in ADS are incomplete because we do not obtain reference lists from all publishers. In addition, we cannot match all references (e.g. in press, private communications, author errors, some conference papers, etc.). Anyone using the citations for analysis of publishing records should keep this in mind. More work on expanding the citation and reference features is planned over the next year. ADS Home Page http://ads.harvard.edu/

  10. Flowing along the edge: spinning up black holes in AdS spacetimes with test particles

    CERN Document Server

    Rocha, Jorge V

    2014-01-01

    We investigate the consequences of throwing point particles into odd-dimensional Myers-Perry black holes in asymptotically anti-de Sitter (AdS) backgrounds. We restrict our attention to the case in which the angular momenta of the background geometry are all equal. This process allows us to test the generalization of the weak cosmic censorship conjecture to asymptotically AdS spacetimes in higher dimensions. We find no evidence for overspinning in D = 5, 7, 9 and 11 dimensions. Instead, test particles carrying the maximum possible angular momentum that still fall into an extremal rotating black hole generate a flow along the curve of extremal solutions.

  11. The generalization of charged AdS black hole specific volume and number density

    Science.gov (United States)

    Wang, Zi-Liang; He, Miao; Fang, Chao; Sun, Dao-Quan; Deng, Jian-Bo

    2017-04-01

    In this paper, by proposing a generalized specific volume, we restudy the P- V criticality of charged AdS black holes in the extended phase space. The results show that most of the previous conclusions can be generalized without change, but the ratio {\\tilde{ρ }}_c should be 3 {\\tilde{α }}/16 in general case. Further research on the thermodynamical phase transition of black hole leads us to a natural interpretation of our assumption, and more black hole properties can be generalized. Finally, we study the number density for charged AdS black hole in higher dimensions, the results show the necessity of our assumption.

  12. Double-trace deformations and entanglement entropy in AdS

    Science.gov (United States)

    Miyagawa, Taiki; Shiba, Noburo; Takayanagi, Tadashi

    2016-01-01

    We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions.

  13. Double-trace deformations and entanglement entropy in AdS

    Energy Technology Data Exchange (ETDEWEB)

    Miyagawa, Taiki [Department of Physics, Kyoto University (Japan); Shiba, Noburo [Yukawa Institute for Theoretical Physics (YITP), Kyoto University (Japan); Takayanagi, Tadashi [Yukawa Institute for Theoretical Physics (YITP), Kyoto University (Japan); Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), University of Tokyo, Kashiwa, Chiba (Japan)

    2016-01-15

    We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Double-Trace Deformations and Entanglement Entropy in AdS

    CERN Document Server

    Miyagawa, Taiki; Takayanagi, Tadashi

    2016-01-01

    We compute the bulk entanglement entropy of a massive scalar field in a Poincare AdS with the Dirichlet and Neumann boundary condition when we trace out a half space. Moreover, by taking into account the quantum back reaction to the minimal surface area, we calculate how much the entanglement entropy changes under a double-trace deformation of a holographic CFT. In the AdS3/CFT2 setup, our result agrees with the known result in 2d CFTs. In higher dimensions, our results offer holographic predictions.

  15. Superradiance Instability of Small Rotating AdS Black Holes in Arbitrary Dimensions

    CERN Document Server

    Delice, Özgür

    2015-01-01

    We investigate the stability of $D$ dimensional singly rotating Myers-Perry-AdS black holes under superradiance against scalar field perturbations. It is well known that small four dimensional rotating or charged AdS black holes are unstable against superradiance instability of a scalar field. Recent works extended the existence of this instability to five dimensional rotating charged AdS black holes or static charged AdS Black holes in arbitrary dimensions. In this work we analytically prove that, rotating small AdS black holes in arbitrary dimensions also show superradiance instability irrespective of the value of the (positive) angular momentum quantum number. To do this we solve the Klein-Gordon equation in the slow rotation, low frequency limit. By using the asymptotic matching technique, we are able to calculate the real and imaginary parts of the correction terms to the frequency of the scalar field due to the presence of the black hole, confirming the presence of superradiance instability. We see that...

  16. Horizon Conformal Field Theories from $AdS_2$ Black Holes

    CERN Document Server

    Halyo, Edi

    2015-01-01

    We show that the very near horizon region of nonextreme black holes, which can be described by horizon CFTs, are related to $AdS_2$ Rindler spaces. The latter are $AdS_2$ black holes with specific masses and can be described by states of either $D=1$ or $D=2$ CFTs. The central charges of these CFTs and the conformal weights of their states that correspond to the nonextreme black holes exactly match those predicted by the horizon CFTs, providing supporting evidence for this description.

  17. Vehicular ad hoc network security and privacy

    CERN Document Server

    Lin, X

    2015-01-01

    Unlike any other book in this area, this book provides innovative solutions to security issues, making this book a must read for anyone working with or studying security measures. Vehicular Ad Hoc Network Security and Privacy mainly focuses on security and privacy issues related to vehicular communication systems. It begins with a comprehensive introduction to vehicular ad hoc network and its unique security threats and privacy concerns and then illustrates how to address those challenges in highly dynamic and large size wireless network environments from multiple perspectives. This book is richly illustrated with detailed designs and results for approaching security and privacy threats.

  18. iAd Production Beginner's Guide

    CERN Document Server

    Collier, Ben

    2012-01-01

    This beginner's guide focuses on getting you through all the major learning points in a smooth, logical order. You'll also see how to avoid some common pitfalls. This book is for brands, advertisers and developers who want to create compelling, emotive, iAd advertisements that generate revenue and increase brand awareness. You don't need previous experience of creating adverts or apps for iPhone and iPad, as you'll be taken through the entire process to make motion-rich, beautiful ads.

  19. Intermittently connected mobile ad hoc networks

    CERN Document Server

    Jamalipour, Abbas

    2011-01-01

    In the last few years, there has been extensive research activity in the emerging area of Intermittently Connected Mobile Ad Hoc Networks (ICMANs). By considering the nature of intermittent connectivity in most real word mobile environments without any restrictions placed on users' behavior, ICMANs are eventually formed without any assumption with regard to the existence of a end-to-end path between two nodes wishing to communicate. It is different from the conventional Mobile Ad Hoc Networks (MANETs), which have been implicitly viewed as a connected graph with established complete paths betwe

  20. QCD condensates in ADS/QCD

    DEFF Research Database (Denmark)

    Bechi, Jacopo

    2009-01-01

    This paper focuses on some issues about condensates and renormalization in AdS/QCD models. In particular we consider the consistency of the AdS/QCD approach for scale dependent quantities as the chiral condensate questioned in some recent papers and the 4D meaning of the 5D cosmological constant...... in a model in which the QCD is dual to a 5D gravity theory. We will be able to give some arguments that the cosmological constant is related to the QCD gluon condensate....