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Sample records for carbohydrate conformation

  1. Shape: automatic conformation prediction of carbohydrates using a genetic algorithm

    Directory of Open Access Journals (Sweden)

    Rosen Jimmy

    2009-09-01

    Full Text Available Abstract Background Detailed experimental three dimensional structures of carbohydrates are often difficult to acquire. Molecular modelling and computational conformation prediction are therefore commonly used tools for three dimensional structure studies. Modelling procedures generally require significant training and computing resources, which is often impractical for most experimental chemists and biologists. Shape has been developed to improve the availability of modelling in this field. Results The Shape software package has been developed for simplicity of use and conformation prediction performance. A trivial user interface coupled to an efficient genetic algorithm conformation search makes it a powerful tool for automated modelling. Carbohydrates up to a few hundred atoms in size can be investigated on common computer hardware. It has been shown to perform well for the prediction of over four hundred bioactive oligosaccharides, as well as compare favourably with previously published studies on carbohydrate conformation prediction. Conclusion The Shape fully automated conformation prediction can be used by scientists who lack significant modelling training, and performs well on computing hardware such as laptops and desktops. It can also be deployed on computer clusters for increased capacity. The prediction accuracy under the default settings is good, as it agrees well with experimental data and previously published conformation prediction studies. This software is available both as open source and under commercial licenses.

  2. Prediction of conformationally dependent atomic multipole moments in carbohydrates.

    Science.gov (United States)

    Cardamone, Salvatore; Popelier, Paul L A

    2015-12-15

    The conformational flexibility of carbohydrates is challenging within the field of computational chemistry. This flexibility causes the electron density to change, which leads to fluctuating atomic multipole moments. Quantum Chemical Topology (QCT) allows for the partitioning of an "atom in a molecule," thus localizing electron density to finite atomic domains, which permits the unambiguous evaluation of atomic multipole moments. By selecting an ensemble of physically realistic conformers of a chemical system, one evaluates the various multipole moments at defined points in configuration space. The subsequent implementation of the machine learning method kriging delivers the evaluation of an analytical function, which smoothly interpolates between these points. This allows for the prediction of atomic multipole moments at new points in conformational space, not trained for but within prediction range. In this work, we demonstrate that the carbohydrates erythrose and threose are amenable to the above methodology. We investigate how kriging models respond when the training ensemble incorporating multiple energy minima and their environment in conformational space. Additionally, we evaluate the gains in predictive capacity of our models as the size of the training ensemble increases. We believe this approach to be entirely novel within the field of carbohydrates. For a modest training set size of 600, more than 90% of the external test configurations have an error in the total (predicted) electrostatic energy (relative to ab initio) of maximum 1 kJ mol(-1) for open chains and just over 90% an error of maximum 4 kJ mol(-1) for rings.

  3. Molecular Clustering Interrelationships and Carbohydrate Conformation in Hull and Seeds Among Barley Cultivars

    Energy Technology Data Exchange (ETDEWEB)

    N Liu; P Yu

    2011-12-31

    The objective of this study was to use molecular spectral analyses with the diffuse reflectance Fourier transform infrared spectroscopy (DRIFT) bioanlytical technique to study carbohydrate conformation features, molecular clustering and interrelationships in hull and seed among six barley cultivars (AC Metcalfe, CDC Dolly, McLeod, CDC Helgason, CDC Trey, CDC Cowboy), which had different degradation kinetics in rumen. The molecular structure spectral analyses in both hull and seed involved the fingerprint regions of ca. 1536-1484 cm{sup -1} (attributed mainly to aromatic lignin semicircle ring stretch), ca. 1293-1212 cm{sup -1} (attributed mainly to cellulosic compounds in the hull), ca. 1269-1217 cm{sup -1} (attributed mainly to cellulosic compound in the seeds), and ca. 1180-800 cm{sup -1} (attributed mainly to total CHO C-O stretching vibrations) together with an agglomerative hierarchical cluster (AHCA) and principal component spectral analyses (PCA). The results showed that the DRIFT technique plus AHCA and PCA molecular analyses were able to reveal carbohydrate conformation features and identify carbohydrate molecular structure differences in both hull and seeds among the barley varieties. The carbohydrate molecular spectral analyses at the region of ca. 1185-800 cm{sup -1} together with the AHCA and PCA were able to show that the barley seed inherent structures exhibited distinguishable differences among the barley varieties. CDC Helgason had differences from AC Metcalfe, MeLeod, CDC Cowboy and CDC Dolly in carbohydrate conformation in the seed. Clear molecular cluster classes could be distinguished and identified in AHCA analysis and the separate ellipses could be grouped in PCA analysis. But CDC Helgason had no distinguished differences from CDC Trey in carbohydrate conformation. These carbohydrate conformation/structure difference could partially explain why the varieties were different in digestive behaviors in animals. The molecular spectroscopy

  4. Enhanced conformational sampling of carbohydrates by Hamiltonian replica-exchange simulation.

    Science.gov (United States)

    Mishra, Sushil Kumar; Kara, Mahmut; Zacharias, Martin; Koca, Jaroslav

    2014-01-01

    Knowledge of the structure and conformational flexibility of carbohydrates in an aqueous solvent is important to improving our understanding of how carbohydrates function in biological systems. In this study, we extend a variant of the Hamiltonian replica-exchange molecular dynamics (MD) simulation to improve the conformational sampling of saccharides in an explicit solvent. During the simulations, a biasing potential along the glycosidic-dihedral linkage between the saccharide monomer units in an oligomer is applied at various levels along the replica runs to enable effective transitions between various conformations. One reference replica runs under the control of the original force field. The method was tested on disaccharide structures and further validated on biologically relevant blood group B, Lewis X and Lewis A trisaccharides. The biasing potential-based replica-exchange molecular dynamics (BP-REMD) method provided a significantly improved sampling of relevant conformational states compared with standard continuous MD simulations, with modest computational costs. Thus, the proposed BP-REMD approach adds a new dimension to existing carbohydrate conformational sampling approaches by enhancing conformational sampling in the presence of solvent molecules explicitly at relatively low computational cost.

  5. Carbohydrate conformation and lipid condensation in monolayers containing glycosphingolipid Gb3: influence of acyl chain structure.

    Science.gov (United States)

    Watkins, Erik B; Gao, Haifei; Dennison, Andrew J C; Chopin, Nathalie; Struth, Bernd; Arnold, Thomas; Florent, Jean-Claude; Johannes, Ludger

    2014-09-01

    Globotriaosylceramide (Gb3), a glycosphingolipid found in the plasma membrane of animal cells, is the endocytic receptor of the bacterial Shiga toxin. Using x-ray reflectivity (XR) and grazing incidence x-ray diffraction (GIXD), lipid monolayers containing Gb3 were investigated at the air-water interface. XR probed Gb3 carbohydrate conformation normal to the interface, whereas GIXD precisely characterized Gb3's influence on acyl chain in-plane packing and area per molecule (APM). Two phospholipids, 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE), were used to study Gb3 packing in different lipid environments. Furthermore, the impact on monolayer structure of a naturally extracted Gb3 mixture was compared to synthetic Gb3 species with uniquely defined acyl chain structures. XR results showed that lipid environment and Gb3 acyl chain structure impact carbohydrate conformation with greater solvent accessibility observed for smaller phospholipid headgroups and long Gb3 acyl chains. In general, GIXD showed that Gb3 condensed phospholipid packing resulting in smaller APM than predicted by ideal mixing. Gb3's capacity to condense APM was larger for DSPC monolayers and exhibited different dependencies on acyl chain structure depending on the lipid environment. The interplay between Gb3-induced changes in lipid packing and the lipid environment's impact on carbohydrate conformation has broad implications for glycosphingolipid macromolecule recognition and ligand binding.

  6. Carbohydrates

    Science.gov (United States)

    Carbohydrates are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar). Your body uses this ...

  7. Molecular architecture with carbohydrate functionalized β-peptides adopting 314-helical conformation

    Directory of Open Access Journals (Sweden)

    Nitin J. Pawar

    2014-04-01

    Full Text Available Carbohydrate recognition is essential in cellular interactions and biological processes. It is characterized by structural diversity, multivalency and cooperative effects. To evaluate carbohydrate interaction and recognition, the structurally defined attachment of sugar units to a rigid template is highly desired. β-Peptide helices offer conformationally stable templates for the linear presentation of sugar units in defined distances. The synthesis and β-peptide incorporation of sugar-β-amino acids are described providing the saccharide units as amino acid side chain. The respective sugar-β-amino acids are accessible by Michael addition of ammonia to sugar units derivatized as α,β-unsaturated esters. Three sugar units were incorporated in β-peptide oligomers varying the sugar (glucose, galactose, xylose and sugar protecting groups. The influence of sugar units and the configuration of sugar-β-amino acids on β-peptide secondary structure were investigated by CD spectroscopy.

  8. A reoptimized GROMOS force field for hexopyranose-based carbohydrates accounting for the relative free energies of ring conformers, anomers, epimers, hydroxymethyl rotamers, and glycosidic linkage conformers.

    Science.gov (United States)

    Hansen, Halvor S; Hünenberger, Philippe H

    2011-04-30

    This article presents a reoptimization of the GROMOS 53A6 force field for hexopyranose-based carbohydrates (nearly equivalent to 45A4 for pure carbohydrate systems) into a new version 56A(CARBO) (nearly equivalent to 53A6 for non-carbohydrate systems). This reoptimization was found necessary to repair a number of shortcomings of the 53A6 (45A4) parameter set and to extend the scope of the force field to properties that had not been included previously into the parameterization procedure. The new 56A(CARBO) force field is characterized by: (i) the formulation of systematic build-up rules for the automatic generation of force-field topologies over a large class of compounds including (but not restricted to) unfunctionalized polyhexopyranoses with arbritrary connectivities; (ii) the systematic use of enhanced sampling methods for inclusion of experimental thermodynamic data concerning slow or unphysical processes into the parameterization procedure; and (iii) an extensive validation against available experimental data in solution and, to a limited extent, theoretical (quantum-mechanical) data in the gas phase. At present, the 56A(CARBO) force field is restricted to compounds of the elements C, O, and H presenting single bonds only, no oxygen functions other than alcohol, ether, hemiacetal, or acetal, and no cyclic segments other than six-membered rings (separated by at least one intermediate atom). After calibration, this force field is shown to reproduce well the relative free energies of ring conformers, anomers, epimers, hydroxymethyl rotamers, and glycosidic linkage conformers. As a result, the 56A(CARBO) force field should be suitable for: (i) the characterization of the dynamics of pyranose ring conformational transitions (in simulations on the microsecond timescale); (ii) the investigation of systems where alternative ring conformations become significantly populated; (iii) the investigation of anomerization or epimerization in terms of free-energy differences

  9. Solution conformation of carbohydrates: a view by using NMR assisted by modeling.

    Science.gov (United States)

    Díaz, Dolores; Canales-Mayordomo, Angeles; Cañada, F Javier; Jiménez-Barbero, Jesús

    2015-01-01

    Structural elucidation of complex carbohydrates in solution is not a trivial task. From the NMR view point, the limited chemical shift dispersion of sugar NMR spectra demands the combination of a variety of NMR techniques as well as the employment of molecular modeling methods. Herein, a general protocol for assignment of resonances and determination of inter-proton distances within the saccharides by homonuclear and heteronuclear experiments (i.e., (1)H and (13)C) is described. In addition, several computational tools and procedures for getting a final ensemble of geometries that represent the structure in solution are presented.

  10. Computerized molecular modeling of carbohydrates

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    Computerized molecular modleing continues to increase in capability and applicability to carbohydrates. This chapter covers nomenclature and conformational aspects of carbohydrates, perhaps of greater use to carbohydrate-inexperienced computational chemists. Its comments on various methods and studi...

  11. Conformational Analysis of the Streptococcus pneumoniae Hyaluronate Lyase and Characterization of Its Hyaluronan-specific Carbohydrate-binding Module*

    Science.gov (United States)

    Suits, Michael D. L.; Pluvinage, Benjamin; Law, Adrienne; Liu, Yan; Palma, Angelina S.; Chai, Wengang; Feizi, Ten; Boraston, Alisdair B.

    2014-01-01

    For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a β-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl. PMID:25100731

  12. Counting carbohydrates

    Science.gov (United States)

    Carb counting; Carbohydrate-controlled diet; Diabetic diet; Diabetes-counting carbohydrates ... Many foods contain carbohydrates (carbs), including: Fruit and fruit juice Cereal, bread, pasta, and rice Milk and milk products, soy milk Beans, legumes, ...

  13. Understanding the differences in molecular conformation of carbohydrate and protein in endosperm tissues of grains with different biodegradation kinetics using advanced synchrotron technology

    Science.gov (United States)

    Yu, P.; Block, H. C.; Doiron, K.

    2009-01-01

    Conventional "wet" chemical analyses rely heavily on the use of harsh chemicals and derivatization, thereby altering native seed structures leaving them unable to detect any original inherent structures within an intact tissue sample. A synchrotron is a giant particle accelerator that turns electrons into light (million times brighter than sunlight) which can be used to study the structure of materials at the molecular level. Synchrotron radiation-based Fourier transform IR microspectroscopy (SR-FTIRM) has been developed as a rapid, direct, non-destructive and bioanalytical technique. This technique, taking advantage of the brightness of synchrotron light and a small effective source size, is capable of exploring the molecular chemistry within the microstructures of a biological tissue without the destruction of inherent structures at ultraspatial resolutions within cellular dimensions. This is in contrast to traditional 'wet' chemical methods, which, during processing for analysis, often result in the destruction of the intrinsic structures of feeds. To date there has been very little application of this technique to the study of plant seed tissue in relation to nutrient utilization. The objective of this study was to use novel synchrotron radiation-based technology (SR-FTIRM) to identify the differences in the molecular chemistry and conformation of carbohydrate and protein in various plant seed endosperms within intact tissues at cellular and subcellular level from grains with different biodegradation kinetics. Barley grain (cv. Harrington) with a high rate (31.3%/h) and extent (78%), corn grain (cv. Pioneer) with a low rate (9.6%/h) and extent of (57%), and wheat grain (cv. AC Barrie) with an intermediate rate (23%/h) and extent (72%) of ruminal DM degradation were selected for evaluation. SR-FTIRM evaluations were performed at the National Synchrotron Light Source at the Brookhaven National Laboratory (Brookhaven, NY). The molecular structure spectral analysis

  14. Understanding the Differences in Molecular Conformation of Carbohydrate and Protein in Endosperm Tissues of Grains with Different Biodegradation Kinetics Using Advanced Synchrotron Technology

    Energy Technology Data Exchange (ETDEWEB)

    Yu, P.; Block, H; Doiron, K

    2009-01-01

    Conventional 'wet' chemical analyses rely heavily on the use of harsh chemicals and derivatization, thereby altering native seed structures leaving them unable to detect any original inherent structures within an intact tissue sample. A synchrotron is a giant particle accelerator that turns electrons into light (million times brighter than sunlight) which can be used to study the structure of materials at the molecular level. Synchrotron radiation-based Fourier transform IR microspectroscopy (SR-FTIRM) has been developed as a rapid, direct, non-destructive and bioanalytical technique. This technique, taking advantage of the brightness of synchrotron light and a small effective source size, is capable of exploring the molecular chemistry within the microstructures of a biological tissue without the destruction of inherent structures at ultraspatial resolutions within cellular dimensions. This is in contrast to traditional 'wet' chemical methods, which, during processing for analysis, often result in the destruction of the intrinsic structures of feeds. To date there has been very little application of this technique to the study of plant seed tissue in relation to nutrient utilization. The objective of this study was to use novel synchrotron radiation-based technology (SR-FTIRM) to identify the differences in the molecular chemistry and conformation of carbohydrate and protein in various plant seed endosperms within intact tissues at cellular and subcellular level from grains with different biodegradation kinetics. Barley grain (cv. Harrington) with a high rate (31.3%/h) and extent (78%), corn grain (cv. Pioneer) with a low rate (9.6%/h) and extent of (57%), and wheat grain (cv. AC Barrie) with an intermediate rate (23%/h) and extent (72%) of ruminal DM degradation were selected for evaluation. SR-FTIRM evaluations were performed at the National Synchrotron Light Source at the Brookhaven National Laboratory (Brookhaven, NY). These results suggest

  15. Gene-Silencing-Induced Changes in Carbohydrate Conformation in Relation to Bioenergy Value and Carbohydrate Subfractions in Modeled Plant (Medicago sativa) with Down-Regulation of HB12 and TT8 Transcription Factors.

    Science.gov (United States)

    Li, Xinxin; Hannoufa, Abdelali; Zhang, Yonggen; Yu, Peiqiang

    2016-05-13

    Gene silencing with RNA interference (RNAi) technology may be capable of modifying internal structure at a molecular level. This structural modification could affect biofunctions in terms of biodegradation, biochemical metabolism, and bioactive compound availability. The objectives of this study were to (1) Detect gene silencing-induced changes in carbohydrate molecular structure in an alfalfa forage (Medicago sativa spp. sativa: alfalfa) with down-regulation of genes that encode transcription factors TT8 and HB12; (2) Determine gene silencing-induced changes in nutrient bioutilization and bioavailability in the alfalfa forage (Medicago sativa); and (3) Quantify the correlation between gene silencing-induced molecular structure changes and the nutrient bioutilization and bioavailability in animals of ruminants. The experimental treatments included: T1 = Non-transgenic and no-gene silenced alfalfa forage (code "NT"); T2 = HB12-RNAi forage with HB12 gene down regulation (code "HB12"); T3 = TT8-RNAi forage with TT8 gene down regulation (code "TT8"). The HB12 and TT8 gene silencing-induced molecular structure changes were determined by non-invasive and non-destructive advanced molecular spectroscopy in a middle infrared radiation region that focused on structural, non-structural and total carbohydrate compounds. The nutrient bioutilization and bioavailability of the modified forage were determined using NRC-2001 system in terms of total digestive nutrient (TDN), truly digestible fiber (tdNDF), non-fiber carbohydrate (tdNDF), fatty acid (tdFA), crude protein (tdCP) and bioenergy profiles (digestible energy, metabolizable energy, net energy) for ruminants. The carbohydrate subfractions were evaluated using the updated CNCPS 6.0 system. The results showed that gene silencing significantly affected tdNFC (42.3 (NT) vs. 38.7 (HB12) vs. 37.4% Dry Matter (TT8); p = 0.016) and tdCP (20.8 (NT) vs. 19.4 (HB12) vs. 22.3% DM (TT8); p = 0.009). The gene-silencing also affected

  16. Carbohydrate Analysis

    Science.gov (United States)

    Bemiller, James N.

    Carbohydrates are important in foods as a major source of energy, to impart crucial textural properties, and as dietary fiber which influences physiological processes. Digestible carbohydrates, which are converted into monosaccharides, which are absorbed, provide metabolic energy. Worldwide, carbohydrates account for more than 70% of the caloric value of the human diet. It is recommended that all persons should limit calories from fat (the other significant source) to not more than 30% and that most of the carbohydrate calories should come from starch. Nondigestible polysaccharides (all those other than starch) comprise the major portion of dietary fiber (Sect. 10.5). Carbohydrates also contribute other attributes, including bulk, body, viscosity, stability to emulsions and foams, water-holding capacity, freeze-thaw stability, browning, flavors, aromas, and a range of desirable textures (from crispness to smooth, soft gels). They also provide satiety. Basic carbohydrate structures, chemistry, and terminology can be found in references (1, 2).

  17. Carbohydrate Loading.

    Science.gov (United States)

    Csernus, Marilyn

    Carbohydrate loading is a frequently used technique to improve performance by altering an athlete's diet. The objective is to increase glycogen stored in muscles for use in prolonged strenuous exercise. For two to three days, the athlete consumes a diet that is low in carbohydrates and high in fat and protein while continuing to exercise and…

  18. Carbohydrate microarrays

    DEFF Research Database (Denmark)

    Park, Sungjin; Gildersleeve, Jeffrey C; Blixt, Klas Ola;

    2012-01-01

    In the last decade, carbohydrate microarrays have been core technologies for analyzing carbohydrate-mediated recognition events in a high-throughput fashion. A number of methods have been exploited for immobilizing glycans on the solid surface in a microarray format. This microarray-based technol...

  19. Carbohydrate malabsorption

    DEFF Research Database (Denmark)

    Rumessen, J J; Nordgaard-Andersen, I; Gudmand-Høyer, E

    1994-01-01

    Previous studies in small series of healthy adults have suggested that parallel measurement of hydrogen and methane resulting from gut fermentation may improve the precision of quantitative estimates of carbohydrate malabsorption. Systematic, controlled studies of the role of simultaneous hydrogen...

  20. Learning about Carbohydrates

    Science.gov (United States)

    ... What Happens in the Operating Room? Learning About Carbohydrates KidsHealth > For Kids > Learning About Carbohydrates A A ... of energy for the body. Two Types of Carbohydrates There are two major types of carbohydrates (or ...

  1. Carbohydrate Stereochemistry.

    Science.gov (United States)

    Shallenberger, Robert S.; Wienen, Wanda J.

    1989-01-01

    Treats the development of general stereochemical principles in historical fashion. Discusses work by Pasteur, van't Hoff, and Le Bel. Considers sugars by configuration, anomeric forms, ring forms, and conformational isomers. Presents numerous diagrams and thorough explanations. (MVL)

  2. Molecular simulations of carbohydrates and protein-carbohydrate interactions: motivation, issues and prospects.

    Science.gov (United States)

    Fadda, Elisa; Woods, Robert J

    2010-08-01

    The characterization of the 3D structure of oligosaccharides, their conjugates and analogs is particularly challenging for traditional experimental methods. Molecular simulation methods provide a basis for interpreting sparse experimental data and for independently predicting conformational and dynamic properties of glycans. Here, we summarize and analyze the issues associated with modeling carbohydrates, with a detailed discussion of four of the most recently developed carbohydrate force fields, reviewed in terms of applicability to natural glycans, carbohydrate-protein complexes and the emerging area of glycomimetic drugs. In addition, we discuss prospectives and new applications of carbohydrate modeling in drug discovery.

  3. Carbohydrates and Diabetes

    Science.gov (United States)

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Carbohydrates and Diabetes KidsHealth > For Teens > Carbohydrates and Diabetes A A A What's in this ... that you should keep track of how many carbohydrates (carbs) you eat. But what exactly are carbohydrates ...

  4. Carbohydrate Metabolism Disorders

    Science.gov (United States)

    ... you eat. Food is made up of proteins, carbohydrates, and fats. Chemicals in your digestive system (enzymes) ... metabolic disorder, something goes wrong with this process. Carbohydrate metabolism disorders are a group of metabolic disorders. ...

  5. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André

    2017-03-01

    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  6. Conformal house

    DEFF Research Database (Denmark)

    Ryttov, Thomas Aaby; Sannino, Francesco

    2010-01-01

    fixed point. As a consistency check we recover the previously investigated bounds of the conformal windows when restricting to a single matter representation. The earlier conformal windows can be imagined to be part now of the new conformal house. We predict the nonperturbative anomalous dimensions...... at the infrared fixed points. We further investigate the effects of adding mass terms to the condensates on the conformal house chiral dynamics and construct the simplest instanton induced effective Lagrangian terms...

  7. Carbohydrates in Supramolecular Chemistry.

    Science.gov (United States)

    Delbianco, Martina; Bharate, Priya; Varela-Aramburu, Silvia; Seeberger, Peter H

    2016-02-24

    Carbohydrates are involved in a variety of biological processes. The ability of sugars to form a large number of hydrogen bonds has made them important components for supramolecular chemistry. We discuss recent advances in the use of carbohydrates in supramolecular chemistry and reveal that carbohydrates are useful building blocks for the stabilization of complex architectures. Systems are presented according to the scaffold that supports the glyco-conjugate: organic macrocycles, dendrimers, nanomaterials, and polymers are considered. Glyco-conjugates can form host-guest complexes, and can self-assemble by using carbohydrate-carbohydrate interactions and other weak interactions such as π-π interactions. Finally, complex supramolecular architectures based on carbohydrate-protein interactions are discussed.

  8. Carbohydrates as food allergens

    OpenAIRE

    SOH, Jian Yi; Huang, Chiung Hui; Lee, Bee Wah

    2015-01-01

    The literature supports the notion that carbohydrate epitopes, on their own, do not contribute significantly to the induction of allergic reactions. They bind weakly to IgE antibodies and have been termed as cross reactive carbohydrate determinants. These epitopes cause confusion in in vitro IgE testing through nonspecific cross-reactivity. Coincident with the rising trends in food allergy prevalence, there has recently been reports of anaphylaxis induced by carbohydrate epitopes. There are t...

  9. Radioiodinated branched carbohydrates

    Science.gov (United States)

    Goodman, Mark M.; Knapp, Jr., Furn F.

    1989-01-01

    A radioiodinated branched carbohydrate for tissue imaging. Iodine-123 is stabilized in the compound by attaching it to a vinyl functional group that is on the carbohydrate. The compound exhibits good uptake and retention and is promising in the development of radiopharmaceuticals for brain, heart and tumor imaging.

  10. Carbohydrates as allergens.

    Science.gov (United States)

    Commins, Scott P

    2015-01-01

    Complex carbohydrates are effective inducers of Th2 responses, and carbohydrate antigens can stimulate the production of glycan-specific antibodies. In instances where the antigen exposure occurs through the skin, the resulting antibody production can contain IgE class antibody. The glycan-stimulated IgE may be non-specific but may also be antigen specific. This review focuses on the production of cross-reactive carbohydrate determinants, the recently identified IgE antibody response to a mammalian oligosaccharide epitope, galactose-alpha-1,3-galactose (alpha-gal), as well as discusses practical implications of carbohydrates in allergy. In addition, the biological effects of carbohydrate antigens are reviewed in setting of receptors and host recognition.

  11. Carbohydrates and Diabetes (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Carbohydrates and Diabetes KidsHealth > For Parents > Carbohydrates and Diabetes ... many kids with diabetes take to stay healthy. Carbohydrates and Blood Sugar The two main forms of ...

  12. Workers’ Conformism

    Directory of Open Access Journals (Sweden)

    Nikolay Ivantchev

    2013-10-01

    Full Text Available Conformism was studied among 46 workers with different kinds of occupations by means of two modified scales measuring conformity by Santor, Messervey, and Kusumakar (2000 – scale for perceived peer pressure and scale for conformism in antisocial situations. The hypothesis of the study that workers’ conformism is expressed in a medium degree was confirmed partly. More than a half of the workers conform in a medium degree for taking risk, and for the use of alcohol and drugs, and for sexual relationships. More than a half of the respondents conform in a small degree for anti-social activities (like a theft. The workers were more inclined to conform for risk taking (10.9%, then – for the use of alcohol, drugs and for sexual relationships (8.7%, and in the lowest degree – for anti-social activities (6.5%. The workers who were inclined for the use of alcohol and drugs tended also to conform for anti-social activities.

  13. CARBOHYDRATE-CONTAINING COMPOUNDS WHICH BIND TO CARBOHYDRATE BINDING RECEPTORS

    DEFF Research Database (Denmark)

    1995-01-01

    Carbohydrate-containing compounds which contain saccharides or derivatives thereof and which bind to carbohydrate binding receptors are useful in pharmaceutical products for treatment of inflammatory diseases and other diseases.......Carbohydrate-containing compounds which contain saccharides or derivatives thereof and which bind to carbohydrate binding receptors are useful in pharmaceutical products for treatment of inflammatory diseases and other diseases....

  14. Carbohydrates and Depression.

    Science.gov (United States)

    Wurtman, Richard J.; Wurtman, Judith J.

    1989-01-01

    Describes the symptoms, such as appetite change and mood fluctuation, basic mechanisms, and some treatments of Seasonal Affective Disorder (SAD), Carbohydrate-Craving Obesity (CCO) and Premenstrual Syndrome (PMS). Provides several tables and diagrams, and three reading references. (YP)

  15. Conformal Infinity

    Science.gov (United States)

    Frauendiener, Jörg

    2004-12-01

    The notion of conformal infinity has a long history within the research in Einstein's theory of gravity. Today, "conformal infinity" is related to almost all other branches of research in general relativity, from quantisation procedures to abstract mathematical issues to numerical applications. This review article attempts to show how this concept gradually and inevitably evolved from physical issues, namely the need to understand gravitational radiation and isolated systems within the theory of gravitation, and how it lends itself very naturally to the solution of radiation problems in numerical relativity. The fundamental concept of null-infinity is introduced. Friedrich's regular conformal field equations are presented and various initial value problems for them are discussed. Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.

  16. Conformal Infinity

    Directory of Open Access Journals (Sweden)

    Frauendiener Jörg

    2000-08-01

    Full Text Available The notion of conformal infinity has a long history within the research in Einstein's theory of gravity. Today, ``conformal infinity'' is related with almost all other branches of research in general relativity, from quantisation procedures to abstract mathematical issues to numerical applications. This review article attempts to show how this concept gradually and inevitably evolved out of physical issues, namely the need to understand gravitational radiation and isolated systems within the theory of gravitation and how it lends itself very naturally to solve radiation problems in numerical relativity. The fundamental concept of null-infinity is introduced. Friedrich's regular conformal field equations are presented and various initial value problems for them are discussed. Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.

  17. Conformal Infinity

    Directory of Open Access Journals (Sweden)

    Frauendiener Jörg

    2004-01-01

    Full Text Available The notion of conformal infinity has a long history within the research in Einstein's theory of gravity. Today, 'conformal infinity' is related to almost all other branches of research in general relativity, from quantisation procedures to abstract mathematical issues to numerical applications. This review article attempts to show how this concept gradually and inevitably evolved from physical issues, namely the need to understand gravitational radiation and isolated systems within the theory of gravitation, and how it lends itself very naturally to the solution of radiation problems in numerical relativity. The fundamental concept of null-infinity is introduced. Friedrich's regular conformal field equations are presented and various initial value problems for them are discussed. Finally, it is shown that the conformal field equations provide a very powerful method within numerical relativity to study global problems such as gravitational wave propagation and detection.

  18. Carbohydrate Mimetic Peptides for Pan Anti-Tumor Responses

    Directory of Open Access Journals (Sweden)

    Thomas eKieber-Emmons

    2014-06-01

    Full Text Available Molecular mimicry is fundamental to biology which transcends to many disciplines ranging from immune pathology to drug design. Structural characterization of molecular partners has provided insight into the origins and relative importance of complementarity in mimicry. Chemical complementarity is easy to understand; amino acid sequence similarity between peptides, for example, can lead to cross-reactivity triggering similar reactivity from their cognate receptors. However, conformational complementarity is difficult to decipher. Molecular mimicry of carbohydrates by peptides is often considered one of those. Extensive studies of innate and adaptive immune responses suggests the existence of carbohydrate mimicry, but the structural basis for this mimicry yields confounding details; peptides mimicking carbohydrates in some cases fail to exhibit both chemical and conformational mimicry. Deconvolution of these two types of complementarity in mimicry and its relationship to biological function can nevertheless lead to new therapeutics. Here, we discuss our experience in bringing a tumor-associated carbohydrate mimetic peptide to the clinic. Emphasis is placed on the rationale, the lessons learned from the methodologies to identify mimics, a perspective on the limitations of structural analysis, the biological consequences of mimicking tumor associated carbohydrate antigens and the notion of reverse engineering to develop carbohydrate mimetic peptides in vaccine design strategies to induce responses to pan-glycan antigens expressed on cancer cells.

  19. Carbohydrates in therapeutics.

    Science.gov (United States)

    Kilcoyne, Michelle; Joshi, Lokesh

    2007-07-01

    Awareness of the importance of carbohydrates in living systems and medicine is growing due to the increasing understanding of their biological and pharmacological relevance. Carbohydrates are ubiquitous and perform a wide array of biological roles. Carbohydrate-based or -modified therapeutics are used extensively in cardiovascular and hematological treatments ranging from inflammatory diseases and anti-thrombotic treatments to wound healing. Heparin is a well-known and widely used example of a carbohydrate-based drug but will not be discussed as it has been extensively reviewed. We will detail carbohydrate-based and -modified therapeutics, both those that are currently marketed or in various stages of clinical trials and those that are potential therapeutics based on promising preclinical investigations. Carbohydrate-based therapeutics include polysaccharide and oligosaccharide anti-inflammatory, anti-coagulant and anti-thrombotic agents from natural and synthetic sources, some as an alternative to heparin and others which were designed based on known structure-functional relationships. Some of these compounds have multiple biological effects, showing anti-adhesive, anti-HIV and anti-arthrithic activities. Small molecules, derivatives or mimetics of complement inhibitors, are detailed for use in limiting ischemia/ reperfusion injuries. Monosaccharides, both natural and synthetic, have been investigated for their in vivo anti-inflammatory and cardioprotective properties. Modification by glycosylation of natural products, or glycosylation-mimicking modification, has a significant effect on the parent molecule including increased plasma half-life and refining or increasing desired functions. It is hoped that this review will highlight the vast therapeutic potential of these natural bioactive molecules.

  20. Carbohydrates, pollinators, and cycads

    Science.gov (United States)

    Marler, Thomas E; Lindström, Anders J

    2015-01-01

    Cycad biology, ecology, and horticulture decisions are not supported by adequate research, and experiments in cycad physiology in particular have been deficient. Our recent report on free sugar content in a range of cycad taxa and tissues sets the stage for developing continued carbohydrate research. Growth and development of cycad pollen, mediation of the herbivory traits of specialist pollinators, and support of expensive strobilus behavioral traits are areas of cycad pollination biology that would benefit from a greater understanding of the role of carbohydrate relations. PMID:26479502

  1. DFT studies of the hydrated carbohydrate, glucose: optimization and DFTMD simulations of ten explicit waters superimposed with an implicit solvation method, COSMO

    Science.gov (United States)

    One of the most important and least understood properties of carbohydrates is their conformational profile in solution. The study of carbohydrates in solution is a most difficult computational problem, a result of the many soft conformational variables (hydroxyl groups) inherent in the structures of...

  2. Carbohydrate structure: the rocky road to automation.

    Science.gov (United States)

    Agirre, Jon; Davies, Gideon J; Wilson, Keith S; Cowtan, Kevin D

    2016-12-08

    With the introduction of intuitive graphical software, structural biologists who are not experts in crystallography are now able to build complete protein or nucleic acid models rapidly. In contrast, carbohydrates are in a wholly different situation: scant automation exists, with manual building attempts being sometimes toppled by incorrect dictionaries or refinement problems. Sugars are the most stereochemically complex family of biomolecules and, as pyranose rings, have clear conformational preferences. Despite this, all refinement programs may produce high-energy conformations at medium to low resolution, without any support from the electron density. This problem renders the affected structures unusable in glyco-chemical terms. Bringing structural glycobiology up to 'protein standards' will require a total overhaul of the methodology. Time is of the essence, as the community is steadily increasing the production rate of glycoproteins, and electron cryo-microscopy has just started to image them in precisely that resolution range where crystallographic methods falter most.

  3. Review: Use of residual dipolar couplings to determine the structure of carbohydrates.

    Science.gov (United States)

    Canales, A; Jiménez-Barbero, J; Martín-Pastor, M

    2012-12-01

    Solution nuclear magnetic resonance spectroscopy is especially useful in the carbohydrate field. The measurement of residual dipolar couplings provides long-range structural information, a valuable complement for the structural study of carbohydrates either in its free form or in the bound state to proteins. They permit to deduce the geometry and the flexibility of the glycosidic linkages, which have a major influence on the conformation of carbohydrates and their overall shape. This article reviews the current application of the residual dipolar couplings methodology to carbohydrates.

  4. Conformational Transitions

    Science.gov (United States)

    Czerminski, Ryszard; Roitberg, Adrian; Choi, Chyung; Ulitsky, Alexander; Elber, Ron

    1991-10-01

    Two computational approaches to study plausible conformations of biological molecules and the transitions between them are presented and discussed. The first approach is a new search algorithm which enhances the sampling of alternative conformers using a mean field approximation. It is argued and demonstrated that the mean field approximation has a small effect on the location of the minima. The method is a combination of the LES protocol (Locally Enhanced Sampling) and simulated annealing. The LES method was used in the past to study the diffusion pathways of ligands from buried active sites in myoglobin and leghemoglobin to the exterior of the protein. The present formulation of LES and its implementation in a Molecular Dynamics program is described. An application for side chain placement in a tetrapeptide is presented. The computational effort associated with conformational searches using LES grows only linearly with the number of degrees of freedom, whereas in the exact case the computational effort grows exponentially. Such saving is of course associated with a mean field approximation. The second branch of studies pertains to the calculation of reaction paths in large and flexible biological systems. An extensive mapping of minima and barriers for two different tetrapeptides is calculated from the known minima and barriers of alanine tetrapeptide which we calculated recently.1 The tetrapeptides are useful models for the formation of secondary structure elements since they are the shortest possible polymers of this type which can still form a complete helical turn. The tetrapeptides are isobutyryl-val(χ1=60)-ala-ala and isobutyryl-val(χ1=-60)-ala-ala. Properties of the hundreds of minima and of the hundreds intervening barriers are discussed. Estimates for thermal transition times between the many conformers (and times to explore the complete phase space) are calculated and compared. It is suggested that the most significant effect of the side chain size is

  5. Carbohydrates, Sugar, and Your Child

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Carbohydrates, Sugar, and Your Child KidsHealth > For Parents > Carbohydrates, Sugar, ... a 1-ounce equivalent. previous continue Sizing Up Sugar Foods that are high in added sugar (soda, ...

  6. Carbohydrate-Mimetic Peptides for Pan Anti-Tumor Responses

    Science.gov (United States)

    Kieber-Emmons, Thomas; Saha, Somdutta; Pashov, Anastas; Monzavi-Karbassi, Behjatolah; Murali, Ramachandran

    2014-01-01

    Molecular mimicry is fundamental to biology and transcends to many disciplines ranging from immune pathology to drug design. Structural characterization of molecular partners has provided insight into the origins and relative importance of complementarity in mimicry. Chemical complementarity is easy to understand; amino acid sequence similarity between peptides, for example, can lead to cross-reactivity triggering similar reactivity from their cognate receptors. However, conformational complementarity is difficult to decipher. Molecular mimicry of carbohydrates by peptides is often considered one of those. Extensive studies of innate and adaptive immune responses suggests the existence of carbohydrate mimicry, but the structural basis for this mimicry yields confounding details; peptides mimicking carbohydrates in some cases fail to exhibit both chemical and conformational mimicry. Deconvolution of these two types of complementarity in mimicry and its relationship to biological function can nevertheless lead to new therapeutics. Here, we discuss our experience examining the immunological aspects and implications of carbohydrate–peptide mimicry. Emphasis is placed on the rationale, the lessons learned from the methodologies to identify mimics, a perspective on the limitations of structural analysis, the biological consequences of mimicking tumor-associated carbohydrate antigens, and the notion of reverse engineering to develop carbohydrate-mimetic peptides in vaccine design strategies to induce responses to glycan antigens expressed on cancer cells. PMID:25071769

  7. Specific Carbohydrate Diet: Does It Work?

    Science.gov (United States)

    ... Specific Carbohydrate Diet (SCD) Go Back The Specific Carbohydrate Diet (SCD) Email Print + Share There is no ... diet that has received attention is the Specific Carbohydrate Diet. This diet limits poorly digestible carbohydrates to ...

  8. Carbohydrates, pollinators, and cycads

    OpenAIRE

    2015-01-01

    Cycad biology, ecology, and horticulture decisions are not supported by adequate research, and experiments in cycad physiology in particular have been deficient. Our recent report on free sugar content in a range of cycad taxa and tissues sets the stage for developing continued carbohydrate research. Growth and development of cycad pollen, mediation of the herbivory traits of specialist pollinators, and support of expensive strobilus behavioral traits are areas of cycad pollination biology th...

  9. Effects of Carbohydrate Consumption Case Study: carbohydrates in Bread

    Directory of Open Access Journals (Sweden)

    Neacsu N.A.

    2014-12-01

    Full Text Available Carbohydrates perform numerous roles in living organisms; they are an important source of energy. The body uses carbohydrates to make glucose which is the fuel that gives it energy and helps keep everything going. However, excess carbohydrate consumption has negative health effects. Bread is a basic product in our nutrition and it also is a product with a high content of carbohydrates. So, it is important to find out more information on bread and on the recommended bread type best for consumption.

  10. Carbohydrate mimetics and scaffolds: sweet spots in medicinal chemistry.

    Science.gov (United States)

    Cipolla, Laura; La Ferla, Barbara; Airoldi, Cristina; Zona, Cristiano; Orsato, Alexandre; Shaikh, Nasrin; Russo, Laura; Nicotra, Francesco

    2010-04-01

    Several glycoprocessing enzymes and glycoreceptors have been recognized as important targets for therapeutic intervention. This concept has inspired the development of important classes of therapeutics, such as anti-influenza drugs inhibiting influenza virus neuraminidase, anti-inflammatory drugs targeting lectin-sialyl-Lewis X interaction and glycosidase inhibitors against HIV, Gaucher's disease, hepatitis and cancer. These therapeutics are mainly carbohydrate mimics in which proper modifications permit stronger interactions with the target protein, higher stability, better pharmacokinetic properties and easier synthesis. Furthermore, the conformational rigidity and polyfunctionality of carbohydrates stimulate their use as scaffolds for the generation of libraries by combinatorial decoration with different pharmacophores. This mini-review will present examples of how to exploit carbohydrates mimics and scaffolds in drug research.

  11. Carbohydrate Microarrays in Plant Science

    DEFF Research Database (Denmark)

    Fangel, Jonatan Ulrik; Pedersen, H.L.; Vidal-Melgosa, S.

    2012-01-01

    industrially and nutritionally. Understanding the biological roles of plant glycans and the effective exploitation of their useful properties requires a detailed understanding of their structures, occurrence, and molecular interactions. Microarray technology has revolutionized the massively high......-throughput analysis of nucleotides, proteins, and increasingly carbohydrates. Using microarrays, the abundance of and interactions between hundreds and thousands of molecules can be assessed simultaneously using very small amounts of analytes. Here we show that carbohydrate microarrays are multifunctional tools...... for plant research and can be used to map glycan populations across large numbers of samples to screen antibodies, carbohydrate binding proteins, and carbohydrate binding modules and to investigate enzyme activities....

  12. Non-conformable, partial and conformable transposition

    DEFF Research Database (Denmark)

    König, Thomas; Mäder, Lars Kai

    2013-01-01

    Although member states are obliged to transpose directives into domestic law in a conformable manner and receive considerable time for their transposition activities, we identify three levels of transposition outcomes for EU directives: conformable, partially conformable and non-conformable...... and the Commission regarding a directive’s outcome, play a much more strategic role than has to date acknowledged in the transposition literature. Whereas disagreement of a member state delays conformable transposition, it speeds up non-conformable transposition. Disagreement of the Commission only prolongs...

  13. Impact of Dietary Carbohydrate and Protein Levels on Carbohydrate Metabolism

    Science.gov (United States)

    Lasker, Denise Ann

    2009-01-01

    The goal of this dissertation was to investigate the impact of changing dietary carbohydrate (CARB) intakes within recommended dietary guidelines on metabolic outcomes specifically associated with glycemic regulations and carbohydrate metabolism. This research utilized both human and animal studies to examine changes in metabolism across a wide…

  14. Conformal transformations and conformal invariance in gravitation

    CERN Document Server

    Dabrowski, Mariusz P; Blaschke, David B

    2008-01-01

    Conformal transformations are frequently used tools in order to study relations between various theories of gravity and Einstein relativity. Because of that, in this paper we discuss the rules of conformal transformations for geometric quantities in general relativity. In particular, we discuss the conformal transformations of the matter energy-momentum tensor. We thoroughly discuss the latter and show the subtlety of the conservation law (i.e., the geometrical Bianchi identity) imposed in one of the conformal frames in reference to the other. The subtlety refers to the fact that conformal transformation ``creates'' an extra matter term composed of the conformal factor which enters the conservation law. In an extreme case of the flat original spacetime the matter is ``created'' due to work done by the conformal transformation to bend the spacetime which was originally flat. We also discuss how to construct the conformally invariant gravity which, in the simplest version, is a special case of the Brans-Dicke t...

  15. Synthesis of carbohydrate-based surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Pemberton, Jeanne E.; Polt, Robin L.; Maier, Raina M.

    2016-11-22

    The present invention provides carbohydrate-based surfactants and methods for producing the same. Methods for producing carbohydrate-based surfactants include using a glycosylation promoter to link a carbohydrate or its derivative to a hydrophobic compound.

  16. Conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in conformal space

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The conformal geometry of regular hypersurfaces in the conformal space is studied.We classify all the conformal isoparametric hypersurfaces with two distinct conformal principal curvatures in the conformal space up to conformal equivalence.

  17. Decarbonylation and dehydrogenation of carbohydrates

    Science.gov (United States)

    Andrews, Mark A.; Klaeren, Stephen A.

    1991-01-01

    Carbohydrates, especially aldose or ketose sugars, including those whose carbonyl group is masked by hemi-acetal or hemi-ketal formation, are decarbonylated by heating the feed carbohydrate together with a transition metal complex in a suitable solvent. Also, primary alcohols, including sugar alditols are simultaneously dehydrogenated and decarbonylated by heating a mixture of rhodium and ruthenium complexes and the alcohol and optionally a hydrogen acceptor in an acceptable solvent. Such defarbonylation and/or dehydrogenation of sugars provides a convenient procedure for the synthesis of certain carbohydrates and may provide a means for the conversion of biomass into useful products.

  18. First steps towards conformationally selective artificial lectins: the chair-boat discrimination by molecularly imprinted polymers.

    Science.gov (United States)

    de Talancé, Vincent Lemau; Massinon, Olivier; Baati, Rachid; Wagner, Alain; Vincent, Stéphane P

    2012-11-07

    A series of molecularly imprinted polymers (MIPs) were prepared in the presence of a synthetic galactoside locked in a (1,4)B boat conformation. This study demonstrates that, depending on the polymerisation technique, an organic material can selectively bind a carbohydrate in a biologically relevant boat conformation.

  19. Carbohydrate microarrays in plant science.

    Science.gov (United States)

    Fangel, Jonatan U; Pedersen, Henriette L; Vidal-Melgosa, Silvia; Ahl, Louise I; Salmean, Armando Asuncion; Egelund, Jack; Rydahl, Maja Gro; Clausen, Mads H; Willats, William G T

    2012-01-01

    Almost all plant cells are surrounded by glycan-rich cell walls, which form much of the plant body and collectively are the largest source of biomass on earth. Plants use polysaccharides for support, defense, signaling, cell adhesion, and as energy storage, and many plant glycans are also important industrially and nutritionally. Understanding the biological roles of plant glycans and the effective exploitation of their useful properties requires a detailed understanding of their structures, occurrence, and molecular interactions. Microarray technology has revolutionized the massively high-throughput analysis of nucleotides, proteins, and increasingly carbohydrates. Using microarrays, the abundance of and interactions between hundreds and thousands of molecules can be assessed simultaneously using very small amounts of analytes. Here we show that carbohydrate microarrays are multifunctional tools for plant research and can be used to map glycan populations across large numbers of samples to screen antibodies, carbohydrate binding proteins, and carbohydrate binding modules and to investigate enzyme activities.

  20. Transition metals in carbohydrate chemistry

    DEFF Research Database (Denmark)

    Madsen, Robert

    1997-01-01

    This review describes the application of transition metal mediated reactions in carbohydrate synthesis. The different metal mediated transformations are divided into reaction types and illustrated by various examples on monosaccharide derivatives. Carbon-carbon bond forming reactions are further ...

  1. Carbohydrate drugs: current status and development prospect.

    Science.gov (United States)

    Zhang, Yan; Wang, Fengshan

    2015-04-01

    In recent years, there has been a great effort devoted to the investigation of the roles of carbohydrates in various essential biological processes and the development of carbohydrates to therapeutic drugs. This review summarizes the carbohydrate drugs which have been recorded in several pharmacopoeias, marketed, and under development. A prospect of the future development of carbohydrate drugs is discussed as well.

  2. A new era of carbohydrate modeling using cutting edge DFT methods

    Science.gov (United States)

    During the last several years we have seen vast improvements in the quality of carbohydrate simulations, including Density Functional Theory (DFT) structure determination and ab initio molecular dynamics studies of low energy conformers of mono-, di-, and larger saccharides at a level of theory that...

  3. Gender Differences in Carbohydrate Metabolism and Carbohydrate Loading

    Directory of Open Access Journals (Sweden)

    Willoughby Darryn

    2006-06-01

    Full Text Available Abstract Prior to endurance competition, many endurance athletes participate in a carbohydrate loading regimen in order to help delay the onset of fatigue. The "classic" regimen generally includes an intense glycogen depleting training period of approximately two days followed by a glycogen loading period for 3–4 days, ingesting approximately 60–70% of total energy intake as carbohydrates, while the newer method does not consist of an intense glycogen depletion protocol. However, recent evidence has indicated that glycogen loading does not occur in the same manner for males and females, thus affecting performance. The scope of this literature review will include a brief description of the role of estradiol in relation to metabolism and gender differences seen in carbohydrate metabolism and loading.

  4. Carbohydrates Through Animation: Preliminary Step

    Directory of Open Access Journals (Sweden)

    J.K. Sugai

    2004-05-01

    Full Text Available Methods of education are changing, so the educational tools must change too. The developmentof the systems of information and communication gave the opportunity to bring new technology tothe learning process. Modern education needs interactive programs that may be available to theacademic community, in order to ease the learning process and sharing of the knowledge. Then,an educational software on Carbohydrates is being developed using concept maps and FLASH-MXanimations program, and approached through six modules. The introduction of Carbohydrates wasmade by the module Carbohydrates on Nature, which shows the animations gures of a teacher andstudents, visiting a farm, identifying the carbohydrates found in vegetables, animals, and microor-ganisms, integrated by links containing short texts to help understanding the structure and functionof carbohydrates. This module was presented, as pilot experiment, to teachers and students, whichdemonstrated satisfaction, and high receptivity, by using animation and interactivitys program asstrategy to biochemistrys education. The present work is part of the project Biochemistry throughanimation, which is having continuity.

  5. Superspace conformal field theory

    Energy Technology Data Exchange (ETDEWEB)

    Quella, Thomas [Koeln Univ. (Germany). Inst. fuer Theoretische Physik; Schomerus, Volker [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-07-15

    Conformal sigma models and WZW models on coset superspaces provide important examples of logarithmic conformal field theories. They possess many applications to problems in string and condensed matter theory. We review recent results and developments, including the general construction of WZW models on type I supergroups, the classification of conformal sigma models and their embedding into string theory.

  6. Protecting groups in carbohydrate chemistry: influence on stereoselectivity of glycosylations.

    Science.gov (United States)

    Guo, Jian; Ye, Xin-Shan

    2010-10-20

    Saccharides are polyhydroxy compounds, and their synthesis requires complex protecting group manipulations. Protecting groups are usually used to temporarily mask a functional group which may interfere with a certain reaction, but protecting groups in carbohydrate chemistry do more than protecting groups usually do. Particularly, protecting groups can participate in reactions directly or indirectly, thus affecting the stereochemical outcomes, which is important for synthesis of oligosaccharides. Herein we present an overview of recent advances in protecting groups influencing stereoselectivity in glycosylation reactions, including participating protecting groups, and conformation-constraining protecting groups in general.

  7. Challenges with nonfiber carbohydrate methods.

    Science.gov (United States)

    Hall, M B

    2003-12-01

    Nonfiber carbohydrates (NFC) encompass a compositionally and nutritionally diverse group exclusive of those carbohydrates found in NDF. Their content in feeds has often been described as a single value estimated by difference as 100% of dry matter minus the percentages of CP, NDF (adjusted for CP in NDF), ether extract, and ash. A calculated value was used because of difficulties with assays for individual NFC, but it does not differentiate among nutritionally distinct NFC. Errors in NFC estimation can arise from not accounting for CP in NDF and when multipliers other than 6.25 are appropriate to estimate CP. Analyses that begin to distinguish among NFC are those for starch, soluble fiber (non-NDF, nonstarch polysaccharides), and low molecular weight carbohydrates (mono- and oligosaccharides). Many starch analyses quantify alpha-glucans through specific hydrolysis of alpha-(1 --> 4) and alpha-(1 --> 6) linkages in the glucan, and measurement of released glucose. Incomplete gelatinization and hydrolysis will lead to underestimation of starch content. Starch values are inflated by enzyme preparations that hydrolyze carbohydrates other than alpha-glucan, measurement of all released monosaccharides without specificity for glucose, and failure to exclude free glucose present in the unhydrolyzed sample. Soluble fiber analyses err in a fashion similar to NFC if estimation of CP requires multipliers other than 6.25, or if contaminants such as CP and starch have not been properly accounted. Depolymerization and incomplete precipitation can also decrease soluble fiber estimates. The low molecular weight carbohydrates have been defined as carbohydrates soluble in 78 to 80% ethanol, which separates them from polysaccharides. They can be measured in extracts using broad-spectrum colorimetric assays (phenol-sulfuric acid assay or reducing sugar analysis of acid hydrolyzed samples) or chromatographic methods. Limitations of the colorimetric assays include lack of differentiation

  8. Biosynthesis of intestinal microvillar proteins. Processing of N-linked carbohydrate is not required for surface expression

    DEFF Research Database (Denmark)

    Danielsen, Erik Michael; Cowell, G M

    1986-01-01

    . The proteinase inhibitor leupeptin partially restored the suppressed synthesis, indicating that the majority of the wrongly processed enzymes, probably because of conformational instability, become degraded soon after synthesis rather than being transported to the microvillar membrane.......Castanospermine, an inhibitor of glucosidase I, the initial enzyme in the trimming of N-linked carbohydrate, was used to study the importance of carbohydrate processing in the biosynthesis of microvillar enzymes in organ-cultured pig intestinal explants. For aminopeptidase N (EC 3...

  9. Biophysical studies on calcium and carbohydrate binding to carbohydrate recognition domain of Gal/GalNAc lectin from Entamoeba histolytica: insights into host cell adhesion.

    Science.gov (United States)

    Yadav, Rupali; Verma, Kuldeep; Chandra, Mintu; Mukherjee, Madhumita; Datta, Sunando

    2016-09-01

    Entamoeba histolytica, an enteric parasite expresses a Gal/GalNAc-specific lectin that contributes to its virulence by establishing adhesion to host cell. In this study, carbohydrate recognition domain of Hgl (EhCRD) was purified and biophysical studies were conducted to understand the thermodynamic basis of its binding to carbohydrate and Ca(++) Here, we show that carbohydrate recognition domain (CRD) of the lectin binds to calcium through DPN motif. To decipher the role of calcium in carbohydrate binding and host cell adhesion, biophysical and cell-based studies were carried out. We demonstrated that the presence of the cation neither change the affinity of the lectin for carbohydrates nor alters its conformation. Mutation of the calcium-binding motif in EhCRD resulted in complete loss of ability to bind calcium but retained its affinity for carbohydrates. Purified EhCRD significantly diminished adhesion of the amebic trophozoites to Chinese Hamster Ovary (CHO) cells as well as triggered red blood cell agglutination. The calcium-binding defective mutant abrogated amebic adhesion to CHO cells similar to the wild-type protein, but it failed to agglutinate RBCs suggesting a differential role of the cation in these two processes. This study provides the first molecular description of the role of calcium in Gal/GalNAc mediated host cell adhesion.

  10. Carbohydrates of human immunodeficiency virus

    DEFF Research Database (Denmark)

    Hansen, J E

    1992-01-01

    Elucidation of the mechanism by which viral infection induces the appearance of carbohydrate neoantigens is highly important. Results from such studies could be expected to be significant for a general understanding of the regulation of glycosylation, and perhaps especially important for the unde...

  11. Racemic carbohydrates - fact or fiction?

    DEFF Research Database (Denmark)

    Senning, Alexander Erich Eugen

    2007-01-01

    Chemical Abstracts Service has developed unsound practices in the naming and handling of simple carbohydrates such as aldopentoses 1, aldohexoses 2, and ketohexoses 3. Typically, the common name glucose is sometimes, inappropriately, interpreted as meaning DL-glucose DL-2d. Thus, a considerable...

  12. Carbohydrate-based immune adjuvants

    Science.gov (United States)

    Petrovsky, Nikolai; Cooper, Peter D

    2011-01-01

    The role for adjuvants in human vaccines has been a matter of vigorous scientific debate, with the field hindered by the fact that for over 80 years, aluminum salts were the only adjuvants approved for human use. To this day, alum-based adjuvants, alone or combined with additional immune activators, remain the only adjuvants approved for use in the USA. This situation has not been helped by the fact that the mechanism of action of most adjuvants has been poorly understood. A relative lack of resources and funding for adjuvant development has only helped to maintain alum’s relative monopoly. To seriously challenge alum’s supremacy a new adjuvant has many major hurdles to overcome, not least being alum’s simplicity, tolerability, safety record and minimal cost. Carbohydrate structures play critical roles in immune system function and carbohydrates also have the virtue of a strong safety and tolerability record. A number of carbohydrate compounds from plant, bacterial, yeast and synthetic sources have emerged as promising vaccine adjuvant candidates. Carbohydrates are readily biodegradable and therefore unlikely to cause problems of long-term tissue deposits seen with alum adjuvants. Above all, the Holy Grail of human adjuvant development is to identify a compound that combines potent vaccine enhancement with maximum tolerability and safety. This has proved to be a tough challenge for many adjuvant contenders. Nevertheless, carbohydrate-based compounds have many favorable properties that could place them in a unique position to challenge alum’s monopoly over human vaccine usage. PMID:21506649

  13. Cationized Carbohydrate Gas-Phase Fragmentation Chemistry

    Science.gov (United States)

    Bythell, Benjamin J.; Abutokaikah, Maha T.; Wagoner, Ashley R.; Guan, Shanshan; Rabus, Jordan M.

    2016-11-01

    We investigate the fragmentation chemistry of cationized carbohydrates using a combination of tandem mass spectrometry, regioselective labeling, and computational methods. Our model system is D-lactose. Barriers to the fundamental glyosidic bond cleavage reactions, neutral loss pathways, and structurally informative cross-ring cleavages are investigated. The most energetically favorable conformations of cationized D-lactose were found to be similar. In agreement with the literature, larger group I cations result in structures with increased cation coordination number which require greater collision energy to dissociate. In contrast with earlier proposals, the B n -Y m fragmentation pathways of both protonated and sodium-cationized analytes proceed via protonation of the glycosidic oxygen with concerted glycosidic bond cleavage. Additionally, for the sodiated congeners our calculations support sodiated 1,6-anhydrogalactose B n ion structures, unlike the preceding literature. This affects the subsequent propensity of formation and prediction of B n /Y m branching ratio. The nature of the anomeric center (α/β) affects the relative energies of these processes, but not the overall ranking. Low-energy cross-ring cleavages are observed for the metal-cationized analytes with a retro-aldol mechanism producing the 0,2 A 2 ion from the sodiated forms. Theory and experiment support the importance of consecutive fragmentation processes, particularly for the protonated congeners at higher collision energies.

  14. Interactions of carbohydrates and proteins by fluorophore-assisted carbohydrate electrophoresis

    Indian Academy of Sciences (India)

    Gang-Liang Huang; Xin-Ya Mei; Peng-George Wang

    2006-06-01

    A sensitive, specific, and rapid method for the detection of carbohydrate-protein interactions is demonstrated by fluorophore-assisted carbohydrate electrophoresis (FACE). The procedure is simple and the cost is low. The advantage of this method is that carbohydrate-protein interactions can be easily displayed by FACE, and the carbohydrates do not need to be purified.

  15. Transitive conformal holonomy groups

    CERN Document Server

    Alt, Jesse

    2011-01-01

    For $(M,[g])$ a conformal manifold of signature $(p,q)$ and dimension at least three, the conformal holonomy group $\\mathrm{Hol}(M,[g]) \\subset O(p+1,q+1)$ is an invariant induced by the canonical Cartan geometry of $(M,[g])$. We give a description of all possible connected conformal holonomy groups which act transitively on the M\\"obius sphere $S^{p,q}$, the homogeneous model space for conformal structures of signature $(p,q)$. The main part of this description is a list of all such groups which also act irreducibly on $\\R^{p+1,q+1}$. For the rest, we show that they must be compact and act decomposably on $\\R^{p+1,q+1}$, in particular, by known facts about conformal holonomy the conformal class $[g]$ must contain a metric which is locally isometric to a so-called special Einstein product.

  16. Disorders of carbohydrate digestion and absorption.

    Science.gov (United States)

    Heitlinger, L A; Lebenthal, E

    1988-04-01

    The carbohydrate malabsorptive syndromes are frequently seen by pediatricians. The congenital deficiency states are quite rare, but adult type hypolactasia and lactose intolerance following rotavirus infection are recognized with increasing frequency by primary care physicians. Therapy for these disorders involves identification of the offending carbohydrate, removal of the carbohydrate from the diet, and exclusion of other entities that may result in carbohydrate malabsorption but not respond to its removal from the diet. Prognosis for both the primary and secondary carbohydrate malabsorption syndromes is excellent. Compliance with diets for those pediatric patients who will require lifelong therapy remains problematic.

  17. Carbohydrate Metabolism in Submariner Personnel

    Science.gov (United States)

    1983-06-01

    metabolism the Wilkerson Point System, for glucose values, used in conjunction with patterns of insulin response described by Kraft(4) serves as the means...amount of exercise and carbohydrate metabolism characteristics occurred in both submariners and non-submariners. An inverse relationship also seems to...individuals(7). In the present study a significant negative correlation was also found between exercise vs one and two hour postprandial glucose and two hour

  18. Carbohydrates Through Animation: Preliminary Step

    OpenAIRE

    J.K. Sugai; M.S.R. Figueiredo; ANTÔNIO, R. V.; P. M. Oliveira; V.A Cardoso; Ricardo, J.; Merino, E.; L.F Figueiredo; D.N. Heidrich

    2004-01-01

    Methods of education are changing, so the educational tools must change too. The developmentof the systems of information and communication gave the opportunity to bring new technology tothe learning process. Modern education needs interactive programs that may be available to theacademic community, in order to ease the learning process and sharing of the knowledge. Then,an educational software on Carbohydrates is being developed using concept maps and FLASH-MXanimations program, and approach...

  19. [Dosimetric evaluation of conformal radiotherapy: conformity factor].

    Science.gov (United States)

    Oozeer, R; Chauvet, B; Garcia, R; Berger, C; Felix-Faure, C; Reboul, F

    2000-01-01

    The aim of three-dimensional conformal therapy (3DCRT) is to treat the Planning Target Volume (PTV) to the prescribed dose while reducing doses to normal tissues and critical structures, in order to increase local control and reduce toxicity. The evaluation tools used for optimizing treatment techniques are three-dimensional visualization of dose distributions, dose-volume histograms, tumor control probabilities (TCP) and normal tissue complication probabilities (NTCP). These tools, however, do not fully quantify the conformity of dose distributions to the PTV. Specific tools were introduced to measure this conformity for a given dose level. We have extended those definitions to different dose levels, using a conformity index (CI). CI is based on the relative volumes of PTV and outside the PTV receiving more than a given dose. This parameter has been evaluated by a clinical study including 82 patients treated for lung cancer and 82 patients treated for prostate cancer. The CI was low for lung dosimetric studies (0.35 at the prescribed dose 66 Gy) due to build-up around the GTV and to spinal cord sparing. For prostate dosimetric studies, the CI was higher (0.57 at the prescribed dose 70 Gy). The CI has been used to compare treatment plans for lung 3DCRT (2 vs 3 beams) and prostate 3DCRT (4 vs 7 beams). The variation of CI with dose can be used to optimize dose prescription.

  20. Conformational stability of calreticulin

    DEFF Research Database (Denmark)

    Jørgensen, C.S.; Trandum, C.; Larsen, N.

    2005-01-01

    The conformational stability of calreticulin was investigated. Apparent unfolding temperatures (T-m) increased from 31 degrees C at pH 5 to 51 degrees C at pH 9, but electrophoretic analysis revealed that calreticulin oligomerized instead of unfolding. Structural analyses showed that the single C......-terminal a-helix was of major importance to the conformational stability of calreticulin....

  1. Conformational stability of calreticulin

    DEFF Research Database (Denmark)

    Jørgensen, Charlotte S; Trandum, Christa; Larsen, Nanna Brink

    2005-01-01

    The conformational stability of calreticulin was investigated. Apparent unfolding temperatures (Tm) increased from 31 degrees C at pH 5 to 51 degrees C at pH 9, but electrophoretic analysis revealed that calreticulin oligomerized instead of unfolding. Structural analyses showed that the single C......-terminal alpha-helix was of major importance to the conformational stability of calreticulin....

  2. A systematic study of chemogenomics of carbohydrates.

    Science.gov (United States)

    Gu, Jiangyong; Luo, Fang; Chen, Lirong; Yuan, Gu; Xu, Xiaojie

    2014-03-04

    Chemogenomics focuses on the interactions between biologically active molecules and protein targets for drug discovery. Carbohydrates are the most abundant compounds in natural products. Compared with other drugs, the carbohydrate drugs show weaker side effects. Searching for multi-target carbohydrate drugs can be regarded as a solution to improve therapeutic efficacy and safety. In this work, we collected 60 344 carbohydrates from the Universal Natural Products Database (UNPD) and explored the chemical space of carbohydrates by principal component analysis. We found that there is a large quantity of potential lead compounds among carbohydrates. Then we explored the potential of carbohydrates in drug discovery by using a network-based multi-target computational approach. All carbohydrates were docked to 2389 target proteins. The most potential carbohydrates for drug discovery and their indications were predicted based on a docking score-weighted prediction model. We also explored the interactions between carbohydrates and target proteins to find the pathological networks, potential drug candidates and new indications.

  3. Carbohydrates

    Science.gov (United States)

    ... products, and do not help you feel as satisfied. FIBER High-fiber foods include: Whole grains, such ... ADAM Health Solutions. About MedlinePlus Site Map FAQs Customer Support Get email updates Subscribe to RSS Follow ...

  4. Conformational energy calculations and proton nuclear overhauser enhancements reveal a unique conformation for blood group A oligosaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Bush, C.A.; Yan, Z.Y.; Rao, B.N.N.

    1986-10-01

    The H NMR spectra of a series of blood group A active oligosaccharides containing from four to ten sugar residues have been completely assigned, and quantitative nuclear Overhauser enhancements (NOE) have been measured between protons separated by known distances within the pyranoside ring. The observation of NOE between anomeric protons and those of the aglycon sugar as well as small effects between protons of distant rings suggests that the oligosaccharides have well-defined conformations. Conformational energy calculations were carried out on a trisaccharide, Fuc( -1 2)(GalNAc( -1 3))-GalUS -O-me, which models the nonreducing terminal fragments of the blood group A oligosaccharides. The results of calculations with three different potential energy functions which have been widely used in peptides and carbohydrates gave several minimum energy conformations. In NOE calculations from conformational models, the rotational correlation time was adjusted to fit T1's and intra-ring NOE. Comparison of calculated maps of NOE as a function of glycosidic dihedral angles showed that only a small region of conformational space was consistent with experimental data on a blood group A tetrasaccharide alditol. This conformation occurs at an energy minimum in all three energy calculations. Temperature dependence of the NOE implies that the oligosaccharides adopt single rigid conformations which do not change with temperature.

  5. Surface characterization of carbohydrate microarrays.

    Science.gov (United States)

    Scurr, David J; Horlacher, Tim; Oberli, Matthias A; Werz, Daniel B; Kroeck, Lenz; Bufali, Simone; Seeberger, Peter H; Shard, Alexander G; Alexander, Morgan R

    2010-11-16

    Carbohydrate microarrays are essential tools to determine the biological function of glycans. Here, we analyze a glycan array by time-of-flight secondary ion mass spectrometry (ToF-SIMS) to gain a better understanding of the physicochemical properties of the individual spots and to improve carbohydrate microarray quality. The carbohydrate microarray is prepared by piezo printing of thiol-terminated sugars onto a maleimide functionalized glass slide. The hyperspectral ToF-SIMS imaging data are analyzed by multivariate curve resolution (MCR) to discern secondary ions from regions of the array containing saccharide, linker, salts from the printing buffer, and the background linker chemistry. Analysis of secondary ions from the linker common to all of the sugar molecules employed reveals a relatively uniform distribution of the sugars within the spots formed from solutions with saccharide concentration of 0.4 mM and less, whereas a doughnut shape is often formed at higher-concentration solutions. A detailed analysis of individual spots reveals that in the larger spots the phosphate buffered saline (PBS) salts are heterogeneously distributed, apparently resulting in saccharide concentrated at the rim of the spots. A model of spot formation from the evaporating sessile drop is proposed to explain these observations. Saccharide spot diameters increase with saccharide concentration due to a reduction in surface tension of the saccharide solution compared to PBS. The multivariate analytical partial least squares (PLS) technique identifies ions from the sugars that in the complex ToF-SIMS spectra correlate with the binding of galectin proteins.

  6. EC declaration of conformity.

    Science.gov (United States)

    Donawa, M E

    1996-05-01

    The CE-marking procedure requires that manufacturers draw up a written declaration of conformity before placing their products on the market. However, some companies do not realize that this is a requirement for all devices. Also, there is no detailed information concerning the contents and format of the EC declaration of conformity in the medical device Directives or in EC guidance documentation. This article will discuss some important aspects of the EC declaration of conformity and some of the guidance that is available on its contents and format.

  7. Applications of synthetic carbohydrates to chemical biology.

    Science.gov (United States)

    Lepenies, Bernd; Yin, Jian; Seeberger, Peter H

    2010-06-01

    Access to synthetic carbohydrates is an urgent need for the development of carbohydrate-based drugs, vaccines, adjuvants as well as novel drug delivery systems. Besides traditional synthesis in solution, synthetic carbohydrates have been generated by chemoenzymatic methods as well as automated solid-phase synthesis. Synthetic oligosaccharides have proven to be useful for identifying ligands of carbohydrate-binding proteins such as C-type lectins and siglecs using glycan arrays. Furthermore, glyconanoparticles and glycodendrimers have been used for specific targeting of lectins of the immune system such as selectins, DC-SIGN, and CD22. This review focuses on how diverse carbohydrate structures can be synthetically derived and highlights the benefit of synthetic carbohydrates for glycobiology.

  8. New fabrication and applications of carbohydrate arrays.

    Science.gov (United States)

    Huang, Gangliang; Chen, Xin; Xiao, Feng

    2014-01-01

    Carbohydrate arrays are used as high-throughput screening platforms to study the carbohydrate-mediated recognition events for glycobiology. The polysaccharide arrays are easy to fabricate by non-covalently or covalently immobilizing polysaccharides onto array surfaces because polysaccharides have hydrophobic interactions. Oligosaccharides must be derived and covalently or non-covalently immobilized onto array surfaces to fabricate oligosaccharide arrays because they have hydrophilic interactions. At the moment, carbohydrate arrays are mainly used to study the carbohydrate-protein interactions and carbohydrate-binding lectins or antibodies, which are possible to be applied to clinics and diagnoses. This review mainly summed up the new fabrication strategies of carbohydrate arrays and their applications in recent four years.

  9. Low-carbohydrate nutrition and metabolism.

    Science.gov (United States)

    Westman, Eric C; Feinman, Richard D; Mavropoulos, John C; Vernon, Mary C; Volek, Jeff S; Wortman, James A; Yancy, William S; Phinney, Stephen D

    2007-08-01

    The persistence of an epidemic of obesity and type 2 diabetes suggests that new nutritional strategies are needed if the epidemic is to be overcome. A promising nutritional approach suggested by this thematic review is carbohydrate restriction. Recent studies show that, under conditions of carbohydrate restriction, fuel sources shift from glucose and fatty acids to fatty acids and ketones, and that ad libitum-fed carbohydrate-restricted diets lead to appetite reduction, weight loss, and improvement in surrogate markers of cardiovascular disease.

  10. Digestion of carbohydrates in the pig.

    Science.gov (United States)

    Drochner, W

    1993-01-01

    A review of carbohydrate digestion in the pig is given. The cascade of digestion in the mouth, stomach, small and large intestine is described. Principles of enzymatic and fermentative digestion according to new results with fistulated animals are discussed. The efficacy and quality of fermentation in the large intestine depending on level and quality of carbohydrates in the diet are demonstrated. Some aspects of energetical efficacy of hindgut digestion are discussed. Dietetic effects of carbohydrates are described.

  11. Regioselective azidotrimethylsilylation of carbohydrates and applications thereof.

    Science.gov (United States)

    L, Mallikharjuna Rao; Yousuf, Syed Khalid; Mukherjee, Debaraj; Taneja, Subhash Chandra

    2012-12-07

    Azidotrimethylsilylation of carbohydrates (monosaccharides and disaccharides) has been achieved in high yields under Mitsunobu conditions. The azidation of carbohydrates is effected at 0 °C essentially only at the primary alcoholic position in mono, di- and triols in protected/unprotected glycosides, whereas the remaining secondary hydroxyl groups got silylated. Surprisingly, no azidation of the secondary hydroxyls was observed in all the carbohydrate substrates. Applications of the methodology for the synthesis of amino sugars, triazoles and azasugars are reported.

  12. The effects of carbohydrate variation in isocaloric diets on glycogenolysis and gluconeogenesis in healthy men

    NARCIS (Netherlands)

    Bisschop, PH; Arias, AMP; Ackermans, MT; Endert, E; Pijl, H; Kuipers, F; Meijer, AJ; Sauerwein, HP; Romijn, JA

    2000-01-01

    To evaluate the effect of dietary carbohydrate content on postabsorptive glucose metabolism, we quantified gluconeogenesis and glycogenolysis after 11 days of high carbohydrate (85% carbohydrate), control (44% carbohydrate), and very low carbohydrate (2% carbohydrate) diets in six healthy men. Diets

  13. Animal culture: chimpanzee conformity?

    Science.gov (United States)

    van Schaik, Carel P

    2012-05-22

    Culture-like phenomena in wild animals have received much attention, but how good is the evidence and how similar are they to human culture? New data on chimpanzees suggest their culture may even have an element of conformity.

  14. Conformal expansions and renormalons

    CERN Document Server

    Gardi, E; Gardi, Einan; Grunberg, Georges

    2001-01-01

    The large-order behaviour of QCD is dominated by renormalons. On the other hand renormalons do not occur in conformal theories, such as the one describing the infrared fixed-point of QCD at small beta_0 (the Banks--Zaks limit). Since the fixed-point has a perturbative realization, all-order perturbative relations exist between the conformal coefficients, which are renormalon-free, and the standard perturbative coefficients, which contain renormalons. Therefore, an explicit cancellation of renormalons should occur in these relations. The absence of renormalons in the conformal limit can thus be seen as a constraint on the structure of the QCD perturbative expansion. We show that the conformal constraint is non-trivial: a generic model for the large-order behaviour violates it. We also analyse a specific example, based on a renormalon-type integral over the two-loop running-coupling, where the required cancellation does occur.

  15. Regioselective monodeprotection of peracetylated carbohydrates.

    Science.gov (United States)

    Filice, Marco; Guisan, Jose M; Terreni, Marco; Palomo, Jose M

    2012-10-01

    This protocol describes the regioselective deprotection of single hydroxyls in peracetylated monosaccharides and disaccharides by enzymatic or chemoenzymatic strategies. The introduction of a one-pot enzymatic step by using immobilized biocatalysts obviates the requirement to carry out tedious workups and time-consuming purifications. By using this straightforward protocol, different per-O-acetylated glycopyranosides (mono- or disaccharides, 1-substituted or glycals) can be transformed into a whole set of differentially monodeprotected 1-alcohols, 3-alcohols, 4-alcohols and 6-alcohols in high yields. These tailor-made glycosyl acceptors can then be used for stereoselective glycosylation for oligosaccharide and glycoderivative synthesis. They have been successfully used as building blocks to synthesize tailor-made di- and trisaccharides involved in the structure of lacto-N-neo-tetraose and precursors of the tumor-associated carbohydrate antigen T and the antitumoral drug peracetylated β-naphtyl-lactosamine. We are able to prepare a purified monoprotected carbohydrate in between 1 and 4 d. With this protocol, the small library of monodeprotected products can be synthesized in 1-2 weeks.

  16. Conformally Coupled Inflation

    Directory of Open Access Journals (Sweden)

    Valerio Faraoni

    2013-07-01

    Full Text Available A massive scalar field in a curved spacetime can propagate along the light cone, a causal pathology, which can, in principle, be eliminated only if the scalar couples conformally to the Ricci curvature of spacetime. This property mandates conformal coupling for the field driving inflation in the early universe. During slow-roll inflation, this coupling can cause super-acceleration and, as a signature, a blue spectrum of primordial gravitational waves.

  17. Delineating the conformal window

    DEFF Research Database (Denmark)

    Frandsen, Mads Toudal; Pickup, Thomas; Teper, Michael

    2011-01-01

    We identify and characterise the conformal window in gauge theories relevant for beyond the standard model building, e.g. Technicolour, using the criteria of metric confinement and causal analytic couplings, which are known to be consistent with the phase diagram of supersymmetric QCD from Seiberg...... duality. Using these criteria we find perturbation theory to be consistent throughout the predicted conformal window for several of these gauge theories and we discuss recent lattice results in the light of our findings....

  18. Conformism and Wealth Distribution

    OpenAIRE

    Mino, Kazuo; Nakamoto, Yasuhiro

    2014-01-01

    This paper explores the role of consumption externalities in a neoclassical growth model in which households have heterogeneous preferences. We fi?nd that the degree of conformism in consumption held by each household signifi?cantly affects the speed of convergence of the aggregate economy as well as the patterns of wealth distribution in the steady state equilibrium. In particular, a higher degree of consumption conformism accelerates the convergence speed of the economy towards the steady s...

  19. Quantum massive conformal gravity

    Energy Technology Data Exchange (ETDEWEB)

    Faria, F.F. [Universidade Estadual do Piaui, Centro de Ciencias da Natureza, Teresina, PI (Brazil)

    2016-04-15

    We first find the linear approximation of the second plus fourth order derivative massive conformal gravity action. Then we reduce the linearized action to separated second order derivative terms, which allows us to quantize the theory by using the standard first order canonical quantization method. It is shown that quantum massive conformal gravity is renormalizable but has ghost states. A possible decoupling of these ghost states at high energies is discussed. (orig.)

  20. Conformally coupled inflation

    CERN Document Server

    Faraoni, Valerio

    2013-01-01

    A massive scalar field in a curved spacetime can propagate along the light cone, a causal pathology, which can, in principle, be eliminated only if the scalar couples conformally to the Ricci curvature of spacetime. This property mandates conformal coupling for the field driving inflation in the early universe. During slow-roll inflation, this coupling can cause super-acceleration and, as a signature, a blue spectrum of primordial gravitational waves.

  1. Biochemical software: Carbohydrates on Laboratory

    Directory of Open Access Journals (Sweden)

    D.N. Heidrich

    2005-07-01

    Full Text Available Educators around  the  world  are  being  challenged  to  develop  and  design  better and  more  effective strategies for student learning  using a variety  of modern  resources.  In this  present  work, an educa- tional  hypermedia  software  was constructed as a support tool to biochemistry teaching.  Occurrence, structure, main  characteristics and  biological  function  of the  biomolecule  Carbohydrates were pre- sented  through  modules.  The  software was developed  using concept  maps,  ISIS-Draw,  and  FLASH- MX animation program.  The chapter  Carbohydrates on Laboratory illustrates experimental methods of carbohydrates characterization, through  animation of a laboratory scenery.   The  subject was de- veloped showing reactions  as Bial, Benedict, Selliwanoff, Barfoed, Phenol  Sulphuric,  and Iodines, and also enzymatic  reactions  as glucose oxidase and amylase.  There are also links with short texts  in order to help the understanding of the contents  and principles of laboratory practice  as well as background reactions. Application of the software to undergraduate students and high school teachers  showed an excellent  acceptance.   All of them  considered  the  software  a very good learning  tool.  Both  teachers and students welcomed this program  as it is more flexible, and allows the learning in a more individual rhythm. In addition, application of the software would be suitable  to a more effective learning  and it is less expensive than conventional experimental teaching.

  2. Wood adhesives containing proteins and carbohydrates

    Science.gov (United States)

    In recent years there has been resurgent interest in using biopolymers as sustainable and environmentally friendly ingredients in wood adhesive formulations. Among them, proteins and carbohydrates are the most commonly used. In this chapter, an overview is given of protein-based and carbohydrate-...

  3. Mastering ectomycorrhizal symbiosis: the impact of carbohydrates.

    Science.gov (United States)

    Nehls, Uwe

    2008-01-01

    Mycorrhiza formation is the consequence of a mutualistic interaction between certain soil fungi and plant roots that helps to overcome nutritional limitations faced by the respective partners. In symbiosis, fungi contribute to tree nutrition by means of mineral weathering and mobilization of nutrients from organic matter, and obtain plant-derived carbohydrates as a response. Support with easily degradable carbohydrates seems to be the driving force for fungi to undergo this type of interaction. As a consequence, the fungal hexose uptake capacity is strongly increased in Hartig net hyphae of the model fungi Amanita muscaria and Laccaria bicolor. Next to fast carbohydrate uptake and metabolism, storage carbohydrates are of special interest. In functional A. muscaria ectomycorrhizas, expression and activity of proteins involved in trehalose biosynthesis is mainly localized in hyphae of the Hartig net, indicating an important function of trehalose in generation of a strong carbon sink by fungal hyphae. In symbiosis, fungal partners receive up to approximately 19 times more carbohydrates from their hosts than normal leakage of the root system would cause, resulting in a strong carbohydrate demand of infected roots and, as a consequence, a more efficient plant photosynthesis. To avoid fungal parasitism, the plant seems to have developed mechanisms to control carbohydrate drain towards the fungal partner and link it to the fungus-derived mineral nutrition. In this contribution, current knowledge on fungal strategies to obtain carbohydrates from its host and plant strategies to enable, but also to control and restrict (under certain conditions), carbon transfer are summarized.

  4. Carbohydrate clearance receptors in transfusion medicine

    DEFF Research Database (Denmark)

    Sørensen, Anne Louise Tølbøll; Clausen, Henrik; Wandall, Hans H

    2012-01-01

    Complex carbohydrates play important functions for circulation of proteins and cells. They provide protective shields and refraction from non-specific interactions with negative charges from sialic acids to enhance circulatory half-life. For recombinant protein therapeutics carbohydrates are espe...

  5. Vacuum ultraviolet photoionization of carbohydrates and nucleotides

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Joong-Won, E-mail: jshin@govst.edu [Division of Science, Governors State University, University Park, Illinois 60484-0975 (United States); Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States); Bernstein, Elliot R., E-mail: erb@lamar.colostate.edu [Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523-1872 (United States)

    2014-01-28

    Carbohydrates (2-deoxyribose, ribose, and xylose) and nucleotides (adenosine-, cytidine-, guanosine-, and uridine-5{sup ′}-monophosphate) are generated in the gas phase, and ionized with vacuum ultraviolet photons (VUV, 118.2 nm). The observed time of flight mass spectra of the carbohydrate fragmentation are similar to those observed [J.-W. Shin, F. Dong, M. Grisham, J. J. Rocca, and E. R. Bernstein, Chem. Phys. Lett. 506, 161 (2011)] for 46.9 nm photon ionization, but with more intensity in higher mass fragment ions. The tendency of carbohydrate ions to fragment extensively following ionization seemingly suggests that nucleic acids might undergo radiation damage as a result of carbohydrate, rather than nucleobase fragmentation. VUV photoionization of nucleotides (monophosphate-carbohydrate-nucleobase), however, shows that the carbohydrate-nucleobase bond is the primary fragmentation site for these species. Density functional theory (DFT) calculations indicate that the removed carbohydrate electrons by the 118.2 nm photons are associated with endocyclic C–C and C–O ring centered orbitals: loss of electron density in the ring bonds of the nascent ion can thus account for the observed fragmentation patterns following carbohydrate ionization. DFT calculations also indicate that electrons removed from nucleotides under these same conditions are associated with orbitals involved with the nucleobase-saccharide linkage electron density. The calculations give a general mechanism and explanation of the experimental results.

  6. Derivatization Reaction of Carbohydrates with Urea as the Reagent and Fluorimetric Determination of Carbohydrates

    Institute of Scientific and Technical Information of China (English)

    YANG,Jing-He(杨景和); CAO,Xi-Hui(曹西慧); WANG,Min(王敏); WU,Xia(吴霞); SUN,Chang-Xia(孙长侠)

    2002-01-01

    It is found that in the presence of sulfuric acid carbohydrates condense with urea to afford the condensation products, which emit fluorescence. Under optimum conditions, the fluorescence intensities of system are proportional to the concentrations of carbohydrates. Based on this linear relationship,quantitative determination of kinds of carbohydrates has been made. Among an the carbohydrates tested, the sensitivity of α-rhamnose is the highest and its limits of detection reaches 3.5 × 10-8 mol/L. So α-rhamnose can be selectively determed in the presence of other carbohydrates. A interaction mechanism is also discussed.

  7. Industrial applications of marine carbohydrates.

    Science.gov (United States)

    Sudha, Prasad N; Aisverya, S; Nithya, R; Vijayalakshmi, K

    2014-01-01

    Biomaterials have been used increasingly in various fields, such as drug delivery, imaging, and tissue engineering. The main reason justifying the widespread use of biomaterials relies on its valuable and low-cost source of new drugs. Current research goals are focused on identifying more potent and specific compounds with antitumor, immunomodulatory, antihyperlipidemic, anticoagulant, and antiviral activities. The increasing knowledge of structural analysis and chemical modifications enables the use of these marine carbohydrates in a newer way for the human welfare. This chapter focuses on the recent developments related to industrial and biomedical applications using chitin, chitosan, alginate, agar, and carrageenan derivatives and reports the main advances published over the last 10-15 years.

  8. Nondigestible carbohydrates and mineral bioavailability.

    Science.gov (United States)

    Greger, J L

    1999-07-01

    Generally, fiber and compounds associated with fiber in cereal products (e.g., phytates) have been found to reduce the apparent absorption of minerals (such as calcium, magnesium, zinc and manganese) in humans, livestock and animal models. The effects of "soluble" forms of fiber (specifically pectins, gums, resistant starches, lactulose, oligofructose and inulin) on mineral absorption are more difficult to characterize. The addition of these soluble forms of fiber has been found in various studies to add viscosity to the gut contents, promote fermentation and the production of volatile fatty acids in the cecum, have a trophic effect on the ceca of animals and increase serum enteroglucagon concentrations. Thus it is not surprising that the addition of soluble forms of fiber to diets often has been found to improve absorption of minerals. This may reflect absorption of electrolytes from the large intestine. Future work should address the mechanisms by which ingestion of nondigestible carbohydrates improves mineral absorption in humans.

  9. Hot Conformal Gauge Theories

    DEFF Research Database (Denmark)

    Mojaza, Matin; Pica, Claudio; Sannino, Francesco

    2010-01-01

    in such a way that the theory develops a perturbative stable infrared fixed point at zero temperature. Due to large distance conformality we trade the coupling constant with its fixed point value and define a reduced free energy which depends only on the number of flavors, colors and matter representation. We...... show that the reduced free energy changes sign, at the second, fifth and sixth order in the coupling, when decreasing the number of flavors from the upper end of the conformal window. If the change in sign is interpreted as signal of an instability of the system then we infer a critical number...... of flavors. Surprisingly this number, if computed to the order g^2, agrees with previous predictions for the lower boundary of the conformal window for nonsupersymmetric gauge theories. The higher order results tend to predict a higher number of critical flavors. These are universal properties, i...

  10. Boundary Conformal Field Theory

    CERN Document Server

    Cardy, J L

    2004-01-01

    Boundary conformal field theory (BCFT) is simply the study of conformal field theory (CFT) in domains with a boundary. It gains its significance because, in some ways, it is mathematically simpler: the algebraic and geometric structures of CFT appear in a more straightforward manner; and because it has important applications: in string theory in the physics of open strings and D-branes, and in condensed matter physics in boundary critical behavior and quantum impurity models. In this article, however, I describe the basic ideas from the point of view of quantum field theory, without regard to particular applications nor to any deeper mathematical formulations.

  11. Conformal General Relativity

    CERN Document Server

    Pervushin, V

    2001-01-01

    The inflation-free solution of problems of the modern cosmology (horizon, cosmic initial data, Planck era, arrow of time, singularity,homogeneity, and so on) is considered in the conformal-invariant unified theory given in the space with geometry of similarity where we can measure only the conformal-invariant ratio of all quantities. Conformal General Relativity is defined as the $SU_c(3)\\times SU(2)\\times U(1)$-Standard Model where the dimensional parameter in the Higgs potential is replaced by a dilaton scalar field described by the negative Penrose-Chernikov-Tagirov action. Spontaneous SU(2) symmetry breaking is made on the level of the conformal-invariant angle of the dilaton-Higgs mixing, and it allows us to keep the structure of Einstein's theory with the equivalence principle. We show that the lowest order of the linearized equations of motion solves the problems mentioned above and describes the Cold Universe Scenario with the constant temperature T and z-history of all masses with respect to an obser...

  12. Conformal cloak for waves

    CERN Document Server

    Chen, Huanyang; Tyc, Tomas

    2011-01-01

    Conformal invisibility devices are only supposed to work within the validity range of geometrical optics. Here we show by numerical simulations and analytical arguments that for certain quantized frequencies they are nearly perfect even in a regime that clearly violates geometrical optics. The quantization condition follows from the analogy between the Helmholtz equation and the stationary Schrodinger equation.

  13. Conformal supermultiplets without superpartners

    CERN Document Server

    Jarvis, Peter

    2011-01-01

    We consider polynomial deformations of Lie superalgebras and their representations. For the class A(n-1,0) ~ sl(n/1), we identify families of superalgebras of quadratic and cubic type, consistent with Jacobi identities. For such deformed superalgebras we point out the possibility of zero step supermultiplets, carried on a single, irreducible representation of the even (Lie) subalgebra. For the conformal group SU(2,2) in 1+3-dimensional spacetime, such irreducible (unitary) representations correspond to standard conformal fields (j_1,j_2;d), where (j_1,j_2) is the spin and d the conformal dimension; in the massless class j_1 j_2=0, and d=j_1+j_2+1. We show that these repesentations are zero step supermultiplets for the superalgebra SU_(2)(2,2/1), the quadratic deformation of conformal supersymmetry SU(2,2/1). We propose to elevate SU_(2)(2,2/1) to a symmetry of the S-matrix. Under this scenario, low-energy standard model matter fields (leptons, quarks, Higgs scalars and gauge fields) descended from such confor...

  14. A CONFORMATIONAL ELASTICITY THEORY

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    A new statistical theory based on the rotational isomeric state model describing the chain conformational free energy has been proposed. This theory can be used to predict different tensions of rubber elongation for chemically different polymers, and the energy term during the elongation of natural rubber coincides with the experimental one.

  15. Conformational changes in biopolymers

    Science.gov (United States)

    Ivanov, Vassili

    2005-12-01

    Biopolymer conformational changes are involved in many biological processes. This thesis summarizes some theoretical and experimental approaches which I have taken at UCLA to explore conformational changes in biopolymers. The reversible thermal denaturation of the DNA double helix is, perhaps, the simplest example of biopolymer conformational change. I have developed a statistical mechanics model of DNA melting with reduced degrees of freedom, which allows base stacking interaction to be taken into account and treat base pairing and stacking separately. Unlike previous models, this model describes both the unpairing and unstacking parts of the experimental melting curves and explains the observed temperature dependence of the effective thermodynamic parameters used in models of the nearest neighbor type. I developed a basic kinetic model for irreversible thermal denaturation of F-actin, which incorporates depolymerization of F-actin from the ends and breaking of F-actin fiber in the middle. The model explains the cooperativity of F-actin thermal denaturation observed by D. Pavlov et al. in differential calorimetry measurements. CG-rich DNA sequences form left-handed Z-DNA at high ionic strength or upon binding of polyvalent ions and some proteins. I studied experimentally the B-to-Z transition of the (CG)6 dodecamer. Improvement of the locally linearized model used to interpret the data gives evidence for an intermediate state in the B-to-Z transition of DNA, contrary to previous research on this subject. In the past 15 years it has become possible to study the conformational changes of biomolecules using single-molecule techniques. In collaboration with other lab members I performed a single-molecule experiment, where we monitored the displacement of a micrometer-size bead tethered to a surface by a DNA probe undergoing the conformational change. This technique allows probing of conformational changes with subnanometer accuracy. We applied the method to detect

  16. Utilization of carbohydrates by radiation processing

    Energy Technology Data Exchange (ETDEWEB)

    Kume, T. E-mail: kume@taka.jaeri.go.jp; Nagasawa, N.; Yoshii, F

    2002-03-01

    Upgrading and utilization of carbohydrates such as chitosan, sodium alginate, carrageenan, cellulose, pectin have been investigated for recycling these bio-resources and reducing the environmental pollution. These carbohydrates were easily degraded by irradiation and various kinds of biological activities such as anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction, etc. were induced. On the other hand, some carbohydrate derivatives, carboxymethylcellulose and carboxymethylstarch, could be crosslinked under certain radiation condition and produce the biodegradable hydrogel for medical and agricultural use.

  17. Carbohydrate functionalized carbon nanotubes and their applications.

    Science.gov (United States)

    Gorityala, Bala Kishan; Ma, Jimei; Wang, Xin; Chen, Peng; Liu, Xue-Wei

    2010-08-01

    Carbon nanotubes (CNTs) have attracted tremendous attention in biomedical applications due to their molecular size and unique properties. This tutorial review summarizes the strategies to functionalize CNTs with bioactive carbohydrates, which improve their solubility, biocompatibility and biofunctionalities while preserving their desired properties. In addition, studies on the usage of carbohydrate functionalized CNTs to detect bacteria, to bind to specific lectins, to deliver glycomimetic drug molecules into cells and to probe cellular activities as biosensors are reviewed. Improvement in biocompatibility and introduction of bio-functionalities by integration of carbohydrate with CNTs are paving the way to glyconanotechnology and may provide new tools for glycobiological studies.

  18. Carbohydrate feeding and exercise: effect of beverage carbohydrate content.

    Science.gov (United States)

    Murray, R; Seifert, J G; Eddy, D E; Paul, G L; Halaby, G A

    1989-01-01

    The purpose of this study was to determine the effect of ingesting fluids of varying carbohydrate content upon sensory response, physiologic function, and exercise performance during 1.25 h of intermittent cycling in a warm environment (Tdb = 33.4 degrees C). Twelve subjects (7 male, 5 female) completed four separate exercise sessions; each session consisted of three 20 min bouts of cycling at 65% VO2max, with each bout followed by 5 min rest. A timed cycling task (1200 pedal revolutions) completed each exercise session. Immediately prior to the first 20 min cycling bout and during each rest period, subjects consumed 2.5 ml.kg BW-1 of water placebo (WP), or solutions of 6%, 8%, or 10% sucrose with electrolytes (20 mmol.l-1 Na+, 3.2 mmol.l-1 K+). Beverages were administered in double blind, counterbalanced order. Mean (+/- SE) times for the 1200 cycling task differed significantly: WP = 13.62 +/- 0.33 min, *6% = 13.03 +/- 0.24 min, 8% = 13.30 +/- 0.25 min, 10% = 13.57 +/- 0.22 min (* = different from WP and 10%, P less than 0.05). Compared to WP, ingestion of the CHO beverages resulted in higher plasma glucose and insulin concentrations, and higher RER values during the final 20 min of exercise (P less than 0.05). Markers of physiologic function and sensory perception changed similarly throughout exercise; no differences were observed among subjects in response to beverage treatments for changes in plasma concentrations of lactate, sodium, potassium, for changes in plasma volume, plasma osmolality, rectal temperature, heart rate, oxygen uptake, rating of perceived exertion, or for indices of gastrointestinal distress, perceived thirst, and overall beverage acceptance.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Workshop to establish databases of carbohydrate spectra

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The workshop was organized to formulate guidelines for establishing spectral databases of complex carbohydrates. The databases will enable the scientific community to avoid the great waste of research effort and funds that frequently occurs when carbohydrate chemists are forced to duplicate the structural characterization of previously characterized complex carbohydrates. Chemists waste their effort on repetitive characterizations because in the absence of spectral databases they are unaware they are analyzing a known molecule until they have completely determined its structure. Chemists will be able to avoid much of this wasted effort when the collections of mass and of nuclear magnetic resonance (NMR) spectra initiated at the workshop are subsequently developed into searchable databases. Then scientists only need query the databases with the spectrum or with information defining the spectrum of an unidentified carbohydrate to find out if it has been previously characterized.

  20. Carbohydrates in pig nutrition - Recent advances

    DEFF Research Database (Denmark)

    Knudsen, Knud Erik Bach; Lærke, Helle Nygaard; Ingerslev, Anne Krog

    2016-01-01

    The dietary carbohydrates are a diverse group of substances with a range of chemical, physical, and physiological properties. The primary chemical classification of carbohydrates is by molecular size (degree of polymerization [DP]), the type of linkage (α or β), and composition of individual...... in the small intestine. Some types of soluble NSP are found to interact with intestinal mucus and produce a layer that significantly delays the transport of lipid digestion products. Potentially, the same may be the case for proteinous compounds. The delay in the transport of the nutrients to the gut...... monomers. This approach divides carbohydrates into 3 main groups, sugars (DP1–2), oligosaccharides (DP3–9), and polysaccharides (DP ≥ 10), the latter being further divided into starch (α-1:4,1,6-D-glucans) and nonstarch polysaccharides (NSP). Dietary fiber (DF) recently has been defined as carbohydrate...

  1. A Conformal Extension Theorem based on Null Conformal Geodesics

    CERN Document Server

    Lübbe, Christian

    2008-01-01

    In this article we describe the formulation of null geodesics as null conformal geodesics and their description in the tractor formalism. A conformal extension theorem through an isotropic singularity is proven by requiring the boundedness of the tractor curvature and its derivatives to sufficient order along a congruence of null conformal geodesic. This article extends earlier work by Tod and Luebbe.

  2. Characterization of protein and carbohydrate mid-IR spectral features in crop residues

    Science.gov (United States)

    Xin, Hangshu; Zhang, Yonggen; Wang, Mingjun; Li, Zhongyu; Wang, Zhibo; Yu, Peiqiang

    2014-08-01

    To the best of our knowledge, a few studies have been conducted on inherent structure spectral traits related to biopolymers of crop residues. The objective of this study was to characterize protein and carbohydrate structure spectral features of three field crop residues (rice straw, wheat straw and millet straw) in comparison with two crop vines (peanut vine and pea vine) by using Fourier transform infrared spectroscopy (FTIR) technique with attenuated total reflectance (ATR). Also, multivariate analyses were performed on spectral data sets within the regions mainly related to protein and carbohydrate in this study. The results showed that spectral differences existed in mid-IR peak intensities that are mainly related to protein and carbohydrate among these crop residue samples. With regard to protein spectral profile, peanut vine showed the greatest mid-IR band intensities that are related to protein amide and protein secondary structures, followed by pea vine and the rest three field crop straws. The crop vines had 48-134% higher spectral band intensity than the grain straws in spectral features associated with protein. Similar trends were also found in the bands that are mainly related to structural carbohydrates (such as cellulosic compounds). However, the field crop residues had higher peak intensity in total carbohydrates region than the crop vines. Furthermore, spectral ratios varied among the residue samples, indicating that these five crop residues had different internal structural conformation. However, multivariate spectral analyses showed that structural similarities still exhibited among crop residues in the regions associated with protein biopolymers and carbohydrate. Further study is needed to find out whether there is any relationship between spectroscopic information and nutrition supply in various kinds of crop residue when fed to animals.

  3. The Origin of the Constant Carbohydrate Diet

    Directory of Open Access Journals (Sweden)

    Charles Herbert Read

    2009-01-01

    Full Text Available The Constant Carbohydrate diet, based entirely on carbohydrate exchanges, is now widely used in the dietary treatment of diabetes mellitus. Being based on sound scientific principles and simple in design, the Constant Carabohydrate diet is appropriate for all those having diabetes mellitus, young or old, no matter their ethncity. This report describes why and how it was developed in 1951. Its simplicity makes it adaptable to all ethnic diets.

  4. The Origin of the Constant Carbohydrate Diet

    Directory of Open Access Journals (Sweden)

    Read CharlesHerbert

    2008-01-01

    Full Text Available The Constant Carbohydrate diet, based entirely on carbohydrate exchanges, is now widely used in the dietary treatment of diabetes mellitus. Being based on sound scientific principles and simple in design, the Constant Carabohydrate diet is appropriate for all those having diabetes mellitus, young or old, no matter their ethncity. This report describes why and how it was developed in 1951. Its simplicity makes it adaptable to all ethnic diets.

  5. Conversion of carbohydrates to levulinic acid esters

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to the field of converting carbohydrates into levulinic acid, a platform chemical for many chemical end products. More specifically the invention relates to a method for converting carbohydrates such as mono-, di- or polysaccharides, obtained from for example biomass...... production into a suitable levulinic acid ester in the presence of a zeolite or zeotype catalyst and a suitable alcohol, and the ester may be further converted into levulinic acid if desired....

  6. Transportation Conformity Training and Presentations

    Science.gov (United States)

    EPA's OTAQ has provided multiple conformity training sessions in the past to assist state and local governments in implementing conformity requirements. As training information is prepared for other venues, it will be posted on this page.

  7. From integrable to conformal theory

    Energy Technology Data Exchange (ETDEWEB)

    Babelon, O. (Paris-6 Univ., 75 (France). Lab. de Physique Theorique et Hautes Energies)

    1990-12-01

    Working in the context of Toda field theory, we establish the relationship between their integrability properties and their conformal structure, thereby clarifying the role of the Yang-Baxter equation in conformal field theory. (orig.).

  8. Multiscale conformal pattern transfer

    Science.gov (United States)

    Lodewijks, Kristof; Miljkovic, Vladimir; Massiot, Inès; Mekonnen, Addis; Verre, Ruggero; Olsson, Eva; Dmitriev, Alexandre

    2016-06-01

    We demonstrate a method for seamless transfer from a parent flat substrate of basically any lithographic top-down or bottom-up pattern onto essentially any kind of surface. The nano- or microscale patterns, spanning macroscopic surface areas, can be transferred with high conformity onto a large variety of surfaces when such patterns are produced on a thin carbon film, grown on top of a sacrificial layer. The latter allows lifting the patterns from the flat parent substrate onto a water-air interface to be picked up by the host surface of choice. We illustrate the power of this technique by functionalizing broad range of materials including glass, plastics, metals, rough semiconductors and polymers, highlighting the potential applications in in situ colorimetry of the chemistry of materials, anti-counterfeit technologies, biomolecular and biomedical studies, light-matter interactions at the nanoscale, conformal photovoltaics and flexible electronics.

  9. Conformal Complementarity Maps

    CERN Document Server

    Barbón, José L F

    2013-01-01

    We study quantum cosmological models for certain classes of bang/crunch singularities, using the duality between expanding bubbles in AdS with a FRW interior cosmology and perturbed CFTs on de Sitter space-time. It is pointed out that horizon complementarity in the AdS bulk geometries is realized as a conformal transformation in the dual deformed CFT. The quantum version of this map is described in full detail in a toy model involving conformal quantum mechanics. In this system the complementarity map acts as an exact duality between eternal and apocalyptic Hamiltonian evolutions. We calculate the commutation relation between the Hamiltonians corresponding to the different frames. It vanishes only on scale invariant states.

  10. Conformational flexibility of aspartame.

    Science.gov (United States)

    Toniolo, Claudio; Temussi, Pierandrea

    2016-05-01

    L-Aspartyl-L-phenylalanine methyl ester, better known as aspartame, is not only one of the most used artificial sweeteners, but also a very interesting molecule with respect to the correlation between molecular structure and taste. The extreme conformational flexibility of this dipeptide posed a huge difficulty when researchers tried to use it as a lead compound to design new sweeteners. In particular, it was difficult to take advantage of its molecular model as a mold to infer the shape of the, then unknown, active site of the sweet taste receptor. Here, we follow the story of the 3D structural aspects of aspartame from early conformational studies to recent docking into homology models of the receptor. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 376-384, 2016.

  11. On conformal lenses

    CERN Document Server

    Chen, Huanyang; Li, Hui

    2011-01-01

    Plane mirror can make one object into two for observers on the object's side. Yet, there seems no way to achieve the same effect for observers from all directions. In this letter, we will design a new class of gradient index lenses from multivalued optical conformal mapping. We shall call them the conformal lenses. Such lenses can transform one source into two (or even many) omnidirectionally. Like the overlapped illusion optics does, they can even transform multiple sources into one. Rather than using negative index materials, implementation here only needs isotropic positive index materials like other gradient index lenses. One obvious drawback however, is that they have singular permittivity values which restrict them to functioning at one single frequency. This however, needs not be the case when applying transmutation methods, which enable the lenses to work in a broadband frequency range.

  12. Conformal boundaries of warped products

    DEFF Research Database (Denmark)

    Kokkendorff, Simon Lyngby

    2006-01-01

    In this note we prove a result on how to determine the conformal boundary of a type of warped product of two length spaces in terms of the individual conformal boundaries. In the situation, that we treat, the warping and conformal distortion functions are functions of distance to a base point....... The result is applied to produce examples of CAT(0)-spaces, where the conformal and ideal boundaries differ in interesting ways....

  13. Two Additional Remarks on Conformism

    OpenAIRE

    Schlicht, Ekkehart

    2014-01-01

    Abstract This note offers two comments on the article “Social Influences towards Conformism in Economic Experiments” by Hargreaves Heap that is to appear in the Economics e-Journal. One relates to the concept of conformism, the other lines out some phenomena where an explicit recognition of group processes, such as conformism, may be analytically helpful.

  14. Metabolic aspects of low carbohydrate diets and exercise

    OpenAIRE

    Peters Sandra; LeBlanc Paul

    2004-01-01

    Abstract Following a low carbohydrate diet, there is a shift towards more fat and less carbohydrate oxidation to provide energy to skeletal muscle, both at rest and during exercise. This review summarizes recent work on human skeletal muscle carbohydrate and fat metabolic adaptations to a low carbohydrate diet, focusing mainly on pyruvate dehydrogenase and pyruvate dehydrogenase kinase, and how these changes relate to the capacity for carbohydrate oxidation during exercise.

  15. Metabolic aspects of low carbohydrate diets and exercise

    Directory of Open Access Journals (Sweden)

    Peters Sandra

    2004-01-01

    Full Text Available Abstract Following a low carbohydrate diet, there is a shift towards more fat and less carbohydrate oxidation to provide energy to skeletal muscle, both at rest and during exercise. This review summarizes recent work on human skeletal muscle carbohydrate and fat metabolic adaptations to a low carbohydrate diet, focusing mainly on pyruvate dehydrogenase and pyruvate dehydrogenase kinase, and how these changes relate to the capacity for carbohydrate oxidation during exercise.

  16. Carbohydrate analysis of Acanthamoeba castellanii.

    Science.gov (United States)

    Dudley, Ricky; Jarroll, Edward L; Khan, Naveed Ahmed

    2009-08-01

    We analyzed biochemically Acanthamoeba castellanii trophozoites, intact cysts and cyst walls belonging to the T4 genotype using gas chromatography combined with mass spectrometry. Cyst walls were prepared by removing intracellular material from cysts by pre-treating them with sodium dodecyl sulphate (SDS) containing dithiothreitol, and then subjecting these to a series of sequential enzymatic digestions using amyloglucosidase, papain, DNase, RNase and proteinase K. The resulting "cyst wall" material was subsequently lyophilized and subjected to glycosyl composition analysis. Transmission electron microscopy confirmed the removal of intracystic material following enzymatic treatment. Our results showed that treated A. castellanii trophozoites, intact cysts and cyst walls contained various sugar moieties, of which a high percentage was galactose and glucose, in addition to small amounts of mannose, and xylose. Linkage analysis revealed several types of glycosidic linkages including the 1,4-linked glucosyl conformation, indicative of cellulose. Inhibitor studies suggested that, beside sugar synthesis, cytoskeletal re-arrangement and mitogen-activated protein kinase-mediated pathways are involved in A. castellanii encystment.

  17. Leaf growth is conformal

    Science.gov (United States)

    Alim, Karen; Armon, Shahaf; Shraiman, Boris I.; Boudaoud, Arezki

    2016-10-01

    Growth pattern dynamics lie at the heart of morphogenesis. Here, we investigate the growth of plant leaves. We compute the conformal transformation that maps the contour of a leaf at a given stage onto the contour of the same leaf at a later stage. Based on the mapping we predict the local displacement field in the leaf blade and find it to agree with the experimentally measured displacement field to 92%. This approach is applicable to any two-dimensional system with locally isotropic growth, enabling the deduction of the whole growth field just from observation of the tissue contour.

  18. Leaf growth is conformal

    CERN Document Server

    Alim, Karen; Shraiman, Boris I; Boudaoud, Arezki

    2016-01-01

    Growth pattern dynamics lie at the heart of morphogenesis. Here, we investigate the growth of plant leaves. We compute the conformal transformation that maps the contour of a leaf at a given stage onto the contour of the same leaf at a later stage. Based on the mapping we predict the local displacement field in the leaf blade and find it to agree with the experimentally measured displacement field to 92%. This approach is applicable to any two-dimensional system with locally isotropic growth, enabling the deduction of the whole growth field just from observation of the tissue contour.

  19. Conformance and Deviance

    DEFF Research Database (Denmark)

    Gjerdrum Pedersen, Esben Rahbek; Neergaard, Peter; Thusgaard Pedersen, Janni

    2013-01-01

    This paper analyses how large Danish companies are responding to new governmental regulation which requires them to report on corporate social responsibility (CSR). The paper is based on an analysis of 142 company annual reports required by the new Danish regulation regarding CSR reporting, plus ...... in CSR reporting practices. Finally, it is argued that non-conformance with the new regulatory requirements is not solely about conscious resistance but may also be caused by, for example, lack of awareness, resource limitations, misinterpretations, and practical difficulties....

  20. Conformal fluid dynamics

    CERN Document Server

    Jarvis, P D

    2006-01-01

    We present a conformal theory of a dissipationless relativistic fluid in 2 space-time dimensions. The theory carries with it a representation of the algebra of 2-$D$ area-preserving diffeomorphisms in the target space of the complex scalar potentials. A complete canonical description is given, and the central charge of the current algebra is calculated. The passage to the quantum theory is discussed in some detail; as a result of operator ordering problems, full quantization at the level of the fields is as yet an open problem.

  1. Potential effect of ultrasound on carbohydrates.

    Science.gov (United States)

    Bera, Smritilekha; Mondal, Dhananjoy; Martin, Jacob T; Singh, Man

    2015-06-17

    The use of ultrasound has emerged as one of the most useful alternative energy sources for the synthesis of carbohydrate-derived biologically and pharmaceutically potential compounds. Spectacular advances have been made in the field of sonication-assisted organic reactions, which are known for producing superior yields, enhanced reactivity of the reactant, improved stereoselectivity, and shortened reaction times. Orthogonal protection-deprotection reactions and/or modification and manipulation of functional groups in carbohydrates are common synthetic steps in carbohydrate chemistry. These reaction steps can be driven by the ultrasonic energy generated by acoustic cavitation via the formation and subsequent collapse of ultrasound-induced bubbles. The ultrasound-assisted synthesis of differently functionalised monosaccharides is useful in a wide variety of applications of carbohydrate chemistry such as the glycosylation of oligosaccharides, one pot domino reactions, thioglycoside syntheses, azidoglycoside syntheses, 1,3-dipolar cycloaddition reactions, and syntheses of natural products. This review article covers ultrasound-mediated reactions on carbohydrates that have been described in the literature since 2000.

  2. Saturated fat, carbohydrate, and cardiovascular disease.

    Science.gov (United States)

    Siri-Tarino, Patty W; Sun, Qi; Hu, Frank B; Krauss, Ronald M

    2010-03-01

    A focus of dietary recommendations for cardiovascular disease (CVD) prevention and treatment has been a reduction in saturated fat intake, primarily as a means of lowering LDL-cholesterol concentrations. However, the evidence that supports a reduction in saturated fat intake must be evaluated in the context of replacement by other macronutrients. Clinical trials that replaced saturated fat with polyunsaturated fat have generally shown a reduction in CVD events, although several studies showed no effects. An independent association of saturated fat intake with CVD risk has not been consistently shown in prospective epidemiologic studies, although some have provided evidence of an increased risk in young individuals and in women. Replacement of saturated fat by polyunsaturated or monounsaturated fat lowers both LDL and HDL cholesterol. However, replacement with a higher carbohydrate intake, particularly refined carbohydrate, can exacerbate the atherogenic dyslipidemia associated with insulin resistance and obesity that includes increased triglycerides, small LDL particles, and reduced HDL cholesterol. In summary, although substitution of dietary polyunsaturated fat for saturated fat has been shown to lower CVD risk, there are few epidemiologic or clinical trial data to support a benefit of replacing saturated fat with carbohydrate. Furthermore, particularly given the differential effects of dietary saturated fats and carbohydrates on concentrations of larger and smaller LDL particles, respectively, dietary efforts to improve the increasing burden of CVD risk associated with atherogenic dyslipidemia should primarily emphasize the limitation of refined carbohydrate intakes and a reduction in excess adiposity.

  3. Carbohydrates and T cells: a sweet twosome.

    Science.gov (United States)

    Avci, Fikri Y; Li, Xiangming; Tsuji, Moriya; Kasper, Dennis L

    2013-04-01

    Carbohydrates as T cell-activating antigens have been generating significant interest. For many years, carbohydrates were thought of as T-independent antigens, however, more recent research had demonstrated that mono- or oligosaccharides glycosidically linked to peptides can be recognized by T cells. T cell recognition of these glycopeptides depends on the structure of both peptide and glycan portions of the antigen. Subsequently, it was discovered that natural killer T cells recognized glycolipids when presented by the antigen presenting molecule CD1d. A transformative insight into glycan-recognition by T cells occurred when zwitterionic polysaccharides were discovered to bind to and be presented by MHCII to CD4+ T cells. Based on this latter observation, the role that carbohydrate epitopes generated from glycoconjugate vaccines had in activating helper T cells was explored and it was found that these epitopes are presented to specific carbohydrate recognizing T cells through a unique mechanism. Here we review the key interactions between carbohydrate antigens and the adaptive immune system at the molecular, cellular and systems levels exploring the significant biological implications in health and disease.

  4. Hot Conformal Gauge Theories

    CERN Document Server

    Mojaza, Matin; Sannino, Francesco

    2010-01-01

    We compute the nonzero temperature free energy up to the order g^6 \\ln(1/g) in the coupling constant for vector like SU(N) gauge theories featuring matter transforming according to different representations of the underlying gauge group. The number of matter fields, i.e. flavors, is arranged in such a way that the theory develops a perturbative stable infrared fixed point at zero temperature. Due to large distance conformality we trade the coupling constant with its fixed point value and define a reduced free energy which depends only on the number of flavors, colors and matter representation. We show that the reduced free energy changes sign, at the second, fifth and sixth order in the coupling, when decreasing the number of flavors from the upper end of the conformal window. If the change in sign is interpreted as signal of an instability of the system then we infer a critical number of flavors. Surprisingly this number, if computed to the order g^2, agrees with previous predictions for the lower boundary o...

  5. Conformal invariant saturation

    CERN Document Server

    Navelet, H

    2002-01-01

    We show that, in onium-onium scattering at (very) high energy, a transition to saturation happens due to quantum fluctuations of QCD dipoles. This transition starts when the order alpha^2 correction of the dipole loop is compensated by its faster energy evolution, leading to a negative interference with the tree level amplitude. After a derivation of the the one-loop dipole contribution using conformal invariance of the elastic 4-gluon amplitude in high energy QCD, we obtain an exact expression of the saturation line in the plane (Y,L) where Y is the total rapidity and L, the logarithm of the onium scale ratio. It shows universal features implying the Balitskyi - Fadin - Kuraev - Lipatov (BFKL) evolution kernel and the square of the QCD triple Pomeron vertex. For large L, only the higher BFKL Eigenvalue contributes, leading to a saturation depending on leading log perturbative QCD characteristics. For initial onium scales of same order, however, it involves an unlimited summation over all conformal BFKL Eigen...

  6. Boronic acids for fluorescence imaging of carbohydrates.

    Science.gov (United States)

    Sun, Xiaolong; Zhai, Wenlei; Fossey, John S; James, Tony D

    2016-02-28

    "Fluorescence imaging" is a particularly exciting and rapidly developing area of research; the annual number of publications in the area has increased ten-fold over the last decade. The rapid increase of interest in fluorescence imaging will necessitate the development of an increasing number of molecular receptors and binding agents in order to meet the demand in this rapidly expanding area. Carbohydrate biomarkers are particularly important targets for fluorescence imaging given their pivotal role in numerous important biological events, including the development and progression of many diseases. Therefore, the development of new fluorescent receptors and binding agents for carbohydrates is and will be increasing in demand. This review highlights the development of fluorescence imaging agents based on boronic acids a particularly promising class of receptors given their strong and selective binding with carbohydrates in aqueous media.

  7. Nutraceutical and pharmacological implications of marine carbohydrates.

    Science.gov (United States)

    Pallela, Ramjee

    2014-01-01

    Current day's research has been focusing much on the potential pharmacological or nutraceutical agents of selective health benefits with less toxicity. As a consequence of increased demand of nutritional supplements of great medicinal values, development of therapeutic agents from natural sources, in particular, marine environment are being considered much important. A diverse array of marine natural products containing medicinally useful nutritional substances, i.e., marine nutraceuticals have been focused to the benefit of mankind. Carbohydrates, by being constituted in considerable amount of many marine organisms display several nutraceutical and pharmaceutical behavior to defend from various diseases. Moreover, the carbohydrates from algae as well as from shellfish wastes, like chitosan and its derivatives, showed tremendous applications in biology and biomedicine. In the current chapter, several of marine carbohydrates from various marine flora and fauna have been covered with their applications and prospects in the development of nutraceuticals and pharmaceuticals.

  8. Investigation of Carbohydrate Recognition via Computer Simulation

    Directory of Open Access Journals (Sweden)

    Quentin R. Johnson

    2015-04-01

    Full Text Available Carbohydrate recognition by proteins, such as lectins and other (biomolecules, can be essential for many biological functions. Recently, interest has arisen due to potential protein and drug design and future bioengineering applications. A quantitative measurement of carbohydrate-protein interaction is thus important for the full characterization of sugar recognition. We focus on the aspect of utilizing computer simulations and biophysical models to evaluate the strength and specificity of carbohydrate recognition in this review. With increasing computational resources, better algorithms and refined modeling parameters, using state-of-the-art supercomputers to calculate the strength of the interaction between molecules has become increasingly mainstream. We review the current state of this technique and its successful applications for studying protein-sugar interactions in recent years.

  9. Capillary electrophoresis-mass spectrometry of carbohydrates.

    Science.gov (United States)

    Zaia, Joseph

    2013-01-01

    The development of methods for capillary electrophoresis (CE) with on-line mass spectrometric detection (CE/MS) is driven by the need for accurate, robust, and sensitive glycomics analysis for basic biomedicine, biomarker discovery, and analysis of recombinant protein therapeutics. One important capability is to profile glycan mixtures with respect to the patterns of substituents including sialic acids, acetate, sulfate, phosphate, and other groups. There is additional need for an MS-compatible separation system capable of resolving carbohydrate isomers. This chapter summarizes applications of CS/MS to analysis of carbohydrates, glycoproteins, and glycopeptides that have appeared since 2008. Readers are referred to recent comprehensive reviews covering earlier publications.

  10. Synthesis of chiral dopants based on carbohydrates.

    Science.gov (United States)

    Tsuruta, Toru; Koyama, Tetsuo; Yasutake, Mikio; Hatano, Ken; Matsuoka, Koji

    2014-07-01

    Chiral dopants based on carbohydrates for nematic liquid crystals were synthesized from D-glucose, and their helical twisting power (HTP) values were evaluated. The chiral dopants induced helices in the host nematic liquid crystals. An acetyl derivative having an ether-type glycosidic linkage between carbohydrate and a mesogenic moiety showed the highest HTP value of 10.4 μm(-1), while an acetyl derivative having an anomeric ester-type linkage did not show any HTP. It was surprising that this molecule had no HTP despite the presence of chirality in the molecule. A relationship between HTP and specific rotation was not observed in this study.

  11. Development of a carbohydrate silylation method in ionic liquids for their gas chromatographic analysis.

    Science.gov (United States)

    Ruiz-Aceituno, L; Carrero-Carralero, C; Ramos, L; Martinez-Castro, I; Sanz, M L

    2013-07-17

    This paper reports on the feasibility of silylation of low molecular weight carbohydrates dissolved in different ionic liquids (ILs) for their further analysis by gas chromatography (GC). Derivatization reagents (nature and amounts), temperature and time of reaction and stirring conditions were evaluated for different carbohydrates (i.e., glucose, mannose, fructose and lactose) dissolved in 1-ethyl-3-methylimidazolium dicyanamide [EMIM][DCA]. Evaluation of conformational isomerism of glucose dissolved in [EMIM][DCA] revealed the effect of the time of dissolution in the equilibration of α- and β-furanoses (up to 3% and 6%, respectively, after 70 h of incubation) and that 21 h sufficed to obtain results similar to those provided by the reference method involving pyridine. Once optimized, the proposed derivatization procedure provided satisfactory yields (i.e., close to 100%) using 100 μL of trimethylsilylimidazole (TMSI) at mild conditions (25°C) for a relatively short time (1h) for most of the investigated carbohydrates. Under these experimental conditions, linear responses (i.e., R(2) better than 0.974) were obtained in the tested range of 0.25-1mg of the derivatized target compounds. Other reagents, such as N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA)+1% trimethylchlorosilane (TMCS), were successfully used under ultrasonic conditions for aldose monosaccharides and disaccharides derivatization, while BSTFA was useful for ketose monosaccharides. The possibility of using the proposed method for the derivatization of selected carbohydrates dissolved in different ILs and the efficiency of the method applied to the analysis of carbohydrates present in real samples (fruit juices) have also been investigated.

  12. Subtleties Concerning Conformal Tractor Bundles

    CERN Document Server

    Graham, C Robin

    2012-01-01

    The realization of tractor bundles as associated bundles in conformal geometry is studied. It is shown that different natural choices of principal bundle with normal Cartan connection corresponding to a given conformal manifold can give rise to topologically distinct associated tractor bundles for the same inducing representation. Consequences for homogeneous models and conformal holonomy are described. A careful presentation is made of background material concerning standard tractor bundles and equivalence between parabolic geometries and underlying structures.

  13. Dimensional Reduction for Conformal Blocks

    CERN Document Server

    Hogervorst, Matthijs

    2016-01-01

    We consider the dimensional reduction of a CFT, breaking multiplets of the d-dimensional conformal group SO(d+1,1) up into multiplets of SO(d,1). This leads to an expansion of d-dimensional conformal blocks in terms of blocks in d-1 dimensions. In particular, we obtain a formula for 3d conformal blocks as an infinite sum over 2F1 hypergeometric functions with closed-form coefficients.

  14. Loop Virasoro Lie conformal algebra

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Henan, E-mail: wuhenanby@163.com; Chen, Qiufan; Yue, Xiaoqing [Department of Mathematics, Tongji University, Shanghai 200092 (China)

    2014-01-15

    The Lie conformal algebra of loop Virasoro algebra, denoted by CW, is introduced in this paper. Explicitly, CW is a Lie conformal algebra with C[∂]-basis (L{sub i} | i∈Z) and λ-brackets [L{sub i} {sub λ} L{sub j}] = (−∂−2λ)L{sub i+j}. Then conformal derivations of CW are determined. Finally, rank one conformal modules and Z-graded free intermediate series modules over CW are classified.

  15. Reflections on Conformal Spectra

    CERN Document Server

    CERN. Geneva

    2015-01-01

    We use modular invariance and crossing symmetry of conformal field theory to reveal approximate reflection symmetries in the spectral decompositions of the partition function in two dimensions in the limit of large central charge and of the four-point function in any dimension in the limit of large scaling dimensions Δ0 of external operators. We use these symmetries to motivate universal upper bounds on the spectrum and the operator product expansion coefficients, which we then derive by independent techniques. Some of the bounds for four-point functions are valid for finite Δ0 as well as for large Δ0. We discuss a similar symmetry in a large spacetime dimension limit. Finally, we comment on the analogue of the Cardy formula and sparse light spectrum condition for the four-point function. (based on 1510.08772 with Kim & Ooguri). This seminar will be given via videolink

  16. Conformal frames in cosmology

    CERN Document Server

    Domènech, Guillem

    2016-01-01

    From higher dimensional theories, e.g. string theory, one expects the presence of non-minimally coupled scalar fields. We review the notion of conformal frames in cosmology and emphasize their physical equivalence, which holds at least at a classical level. Furthermore, if there is a field, or fields, which dominates the universe, as it is often the case in cosmology, we can use such notion of frames to treat our system, matter and gravity, as two different sectors. On one hand, the gravity sector which describes the dynamics of the geometry and on the other hand the matter sector which has such geometry as a playground. We use this interpretation to build a model where the fact that a curvaton couples to a particular frame metric could leave an imprint in the CMB.

  17. Reflections on Conformal Spectra

    CERN Document Server

    Kim, Hyungrok; Ooguri, Hirosi

    2015-01-01

    We use modular invariance and crossing symmetry of conformal field theory to reveal approximate reflection symmetries in the spectral decompositions of the partition function in two dimensions in the limit of large central charge and of the four-point function in any dimension in the limit of large scaling dimensions $\\Delta_0$ of external operators. We use these symmetries to motivate universal upper bounds on the spectrum and the operator product expansion coefficients, which we then derive by independent techniques. Some of the bounds for four-point functions are valid for finite $\\Delta_0$ as well as for large $\\Delta_0$. We discuss a similar symmetry in a large spacetime dimension limit. Finally, we comment on the analogue of the Cardy formula and sparse light spectrum condition for the four-point function.

  18. Separation and quantification of microalgal carbohydrates.

    Science.gov (United States)

    Templeton, David W; Quinn, Matthew; Van Wychen, Stefanie; Hyman, Deborah; Laurens, Lieve M L

    2012-12-28

    Structural carbohydrates can constitute a large fraction of the dry weight of algal biomass and thus accurate identification and quantification is important for summative mass closure. Two limitations to the accurate characterization of microalgal carbohydrates are the lack of a robust analytical procedure to hydrolyze polymeric carbohydrates to their respective monomers and the subsequent identification and quantification of those monosaccharides. We address the second limitation, chromatographic separation of monosaccharides, here by identifying optimum conditions for the resolution of a synthetic mixture of 13 microalgae-specific monosaccharides, comprised of 8 neutral, 2 amino sugars, 2 uronic acids and 1 alditol (myo-inositol as an internal standard). The synthetic 13-carbohydrate mix showed incomplete resolution across 11 traditional high performance liquid chromatography (HPLC) methods, but showed improved resolution and accurate quantification using anion exchange chromatography (HPAEC) as well as alditol acetate derivatization followed by gas chromatography (for the neutral- and amino-sugars only). We demonstrate the application of monosaccharide quantification using optimized chromatography conditions after sulfuric acid analytical hydrolysis for three model algae strains and compare the quantification and complexity of monosaccharides in analytical hydrolysates relative to a typical terrestrial feedstock, sugarcane bagasse.

  19. Genetics of carbohydrate accumulation in onion

    Science.gov (United States)

    Fructans are soluble carbohydrates composed of fructose chains attached to a basal sucrose molecule and act both as health-enhancing pro- and pre-biotics. In onion, higher fructan concentrations are correlated with greater soluble solids content, dry weights, and pungency. We analyzed dry weights ...

  20. General Properties, Occurrence, and Preparation of Carbohydrates

    Science.gov (United States)

    Robyt, John F.

    D-Glucose and its derivatives and analogues, N-acetyl-D-glucosamine, N-acetyl-D-muramic acid, D-glucopyranosyl uronic acid, and D-glucitol represent 99.9% of the carbohydrates on the earth. D-Glucose is found in the free state in human blood and in the combined state in disaccharides, sucrose, lactose, and α,α-trehalose, in cyclic dextrins, and in polysaccharides, starch, glycogen, cellulose, dextrans; N-acetyl-D-glucosamine and an analogue N-acetyl-D-muramic acid are found in bacterial cell wall polysaccharide, murein, along with teichoic acids made up of poly-glycerol or -ribitol phosphodiesters. Other carbohydrates, D-mannose, D-mannuronic acid, D-galactose, N-acetyl-D-galactosamine, D-galacturonic acid, D-iduronic acid, L-guluronic acid, L-rhamnose, L-fucose, D-xylose, and N-acetyl-D-neuraminic acid are found in glycoproteins, hemicelluloses, glycosaminoglycans, and polysaccharides of plant exudates, bacterial capsules, alginates, and heparin. D-Ribofuranose-5-phosphate is found in many coenzymes and is the backbone of RNAs (ribonucleic acid), and 2-deoxy-D-ribofuranose-5-phosphate is the backbone of DNA (deoxyribonucleic acid). D-Fructofuranose is found in sucrose, inulin, and levan. The general properties and occurrence of these carbohydrates and general methods of isolation and preparation of carbohydrates are presented.

  1. Selective carbohydrate utilization by lactobacilli and bifidobacteria

    NARCIS (Netherlands)

    Watson, D.; O'Connell Motherway, M.; Schoterman, M.H.C.; Neerven, van R.J.J.; Nauta, A.; Sinderen, van D.

    2013-01-01

    Aim - To evaluate the ability of specific carbohydrates, including commercially available products, to support the growth of representatives of two well-known groups of gut commensals, namely lactobacilli and bifidobacteria. Methods and Results - Sixty-eight bacterial strains, representing 29 human-

  2. Cell surface carbohydrates as prognostic markers in human carcinomas

    DEFF Research Database (Denmark)

    Dabelsteen, Erik

    1996-01-01

    Tumour development is usually associated with changes in cell surface carbohydrates. These are often divided into changes related to terminal carbohydrate structures, which include incomplete synthesis and modification of normally existing carbohydrates, and changes in the carbohydrate core...... structure. The latter includes chain elongation of both glycolipids and proteins, increased branching of carbohydrates in N-linked glycoproteins, and blocked synthesis of carbohydrates in O-linked mucin-like glycoproteins. In mature organisms, expression of distinct carbohydrates is restricted to specific...... cell types; within a given tissue, variation in expression may be related to cell maturation. Tumour-associated carbohydrate structures often reflect a certain stage of cellular development; most of these moieties are structures normally found in other adult or embryonic tissues. There is no unique...

  3. Replacement between conformity and counter-conformity in consumption decisions.

    Science.gov (United States)

    Chou, Ting-Jui; Chang, En-Chung; Dai, Qi; Wong, Veronica

    2013-02-01

    This study assessed, in a Chinese context, how self-esteem interacts with perceived similarity and uniqueness to yield cognitive dissonance, and whether the dissonance leads to self-reported conformity or counter-conformity behavior. Participants were 408 respondents from 4 major Chinese cities (M age = 33.0 yr., SD = 4.3; 48% men). Self-perceptions of uniqueness, similarity, cognitive dissonance, self-esteem and need to behave in conformity or counter-conformity were measured. A theoretical model was assessed in four situations, relating the ratings of self-esteem and perceived similarity/uniqueness to the way other people at a wedding were dressed, and the resultant cognitive dissonance and conformity/ counter-conformity behavior. Regardless of high or low self-esteem, all participants reported cognitive dissonance when they were told that they were dressed extremely similarly to or extremely differently from the other people attending the wedding. However, the conforming/counter-conforming strategies used by participants to resolve the cognitive dissonance differed. When encountering dissonance induced by the perceived extreme uniqueness of dress, participants with low self-esteem tended to say they would dress next time so as to conform with the way others were dressed, while those with high self-esteem indicated they would continue their counter-conformity in attire. When encountering dissonance induced by the perceived extreme similarity to others, both those with high and low self-esteem tended to say they would dress in an unorthodox manner to surprise other people in the future.

  4. Exercise and Regulation of Carbohydrate Metabolism.

    Science.gov (United States)

    Mul, Joram D; Stanford, Kristin I; Hirshman, Michael F; Goodyear, Laurie J

    2015-01-01

    Carbohydrates are the preferred substrate for contracting skeletal muscles during high-intensity exercise and are also readily utilized during moderate intensity exercise. This use of carbohydrates during physical activity likely played an important role during the survival of early Homo sapiens, and genes and traits regulating physical activity, carbohydrate metabolism, and energy storage have undoubtedly been selected throughout evolution. In contrast to the life of early H. sapiens, modern lifestyles are predominantly sedentary. As a result, intake of excessive amounts of carbohydrates due to the easy and continuous accessibility to modern high-energy food and drinks has not only become unnecessary but also led to metabolic diseases in the face of physical inactivity. A resulting metabolic disease is type 2 diabetes, a complex endocrine disorder characterized by abnormally high concentrations of circulating glucose. This disease now affects millions of people worldwide. Exercise has beneficial effects to help control impaired glucose homeostasis with metabolic disease, and is a well-established tool to prevent and combat type 2 diabetes. This chapter focuses on the effects of exercise on carbohydrate metabolism in skeletal muscle and systemic glucose homeostasis. We will also focus on the molecular mechanisms that mediate the effects of exercise to increase glucose uptake in skeletal muscle. It is now well established that there are different proximal signaling pathways that mediate the effects of exercise and insulin on glucose uptake, and these distinct mechanisms are consistent with the ability of exercise to increase glucose uptake in the face of insulin resistance in people with type 2 diabetes. Ongoing research in this area is aimed at defining the precise mechanism by which exercise increases glucose uptake and insulin sensitivity and the types of exercise necessary for these important health benefits.

  5. Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

    OpenAIRE

    Thomas Kieber-Emmons; Anastas Pashov; Behjatolah Monzavi-Karbassi; Fariba Jousheghany; Cecile Artaud; Leah Hennings

    2011-01-01

    Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- an...

  6. Counselor Identity: Conformity or Distinction?

    Science.gov (United States)

    McLaughlin, Jerry E.; Boettcher, Kathryn

    2009-01-01

    The authors explore 3 debates in other disciplines similar to counseling's identity debate in order to learn about common themes and outcomes. Conformity, distinction, and cohesion emerged as common themes. They conclude that counselors should retain their distinctive, humanistic approach rather than conforming to the dominant, medical approach.

  7. Water drives peptide conformational transitions

    CERN Document Server

    Nerukh, Dmitry

    2011-01-01

    Transitions between metastable conformations of a dipeptide are investigated using classical molecular dynamics simulation with explicit water molecules. The distribution of the surrounding water at different moments before the transitions and the dynamical correlations of water with the peptide's configurational motions indicate that water is the main driving force of the conformational changes.

  8. The effect of stereochemistry on carbohydrate hydration in aqueous solutions

    NARCIS (Netherlands)

    Galema, Saskia Alexandra

    1992-01-01

    Although-carbohydrates are widely used, not much is known about the stereochemical aspects of hydration of carbohydrates. For D-aldohexoses, for example, there are eight different stereoisomers. Just how the hydroxy topology of a carbohydrate molecule influences the hydration behaviour in water is r

  9. Imaging of conformational changes

    Energy Technology Data Exchange (ETDEWEB)

    Michl, Josef [Univ. of Colorado, Boulder, CO (United States)

    2016-03-13

    Control of intramolecular conformational change in a small number of molecules or even a single one by an application of an outside electric field defined by potentials on nearby metal or dielectric surfaces has potential applications in both 3-D and 2-D nanotechnology. Specifically, the synthesis, characterization, and understanding of designed solids with controlled built-in internal rotational motion of a dipole promises a new class of materials with intrinsic dielectric, ferroelectric, optical and optoelectronic properties not found in nature. Controlled rotational motion is of great interest due to its expected utility in phenomena as diverse as transport, current flow in molecular junctions, diffusion in microfluidic channels, and rotary motion in molecular machines. A direct time-resolved observation of the dynamics of motion on ps or ns time scale in a single molecule would be highly interesting but is also very difficult and has yet to be accomplished. Much can be learned from an easier but still challenging comparison of directly observed initial and final orientational states of a single molecule, which is the basis of this project. The project also impacts the understanding of surface-enhanced Raman spectroscopy (SERS) and single-molecule spectroscopic detection, as well as the synthesis of solid-state materials with tailored properties from designed precursors.

  10. Eikonalization of Conformal Blocks

    CERN Document Server

    Fitzpatrick, A Liam; Walters, Matthew T; Wang, Junpu

    2015-01-01

    Classical field configurations such as the Coulomb potential and Schwarzschild solution are built from the $t$-channel exchange of many light degrees of freedom. We study the CFT analog of this phenomenon, which we term the `eikonalization' of conformal blocks. We show that when an operator $T$ appears in the OPE $\\mathcal{O}(x) \\mathcal{O}(0)$, then the large spin $\\ell$ Fock space states $[TT \\cdots T]_{\\ell}$ also appear in this OPE with a computable coefficient. The sum over the exchange of these Fock space states in an $\\langle \\mathcal{O} \\mathcal{O} \\mathcal{O} \\mathcal{O} \\rangle$ correlator build the classical `$T$ field' in the dual AdS description. In some limits the sum of all Fock space exchanges can be represented as the exponential of a single $T$ exchange in the 4-pt correlator of $\\mathcal{O}$. Our results should be useful for systematizing $1/\\ell$ perturbation theory in general CFTs and simplifying the computation of large spin OPE coefficients. As examples we obtain the leading $\\log \\ell$...

  11. The Conformal Standard Model

    CERN Document Server

    Latosinski, Adam; Meissner, Krzysztof A; Nicolai, Hermann

    2015-01-01

    We present an extended version of the Conformal Standard Model (characterized by the absence of any new intermediate scales between the electroweak scale and the Planck scale) with an enlarged scalar sector coupling to right-chiral neutrinos in such a way that the scalar potential and the Yukawa couplings involving only right-chiral neutrinos are invariant under a new global symmetry SU(3)$_N$ which is broken explicitly only by the Yukawa interaction coupling right-chiral neutrinos and the electroweak lepton doublets. We point out four main advantages of such an enlargement, namely: (1) the economy of the (non-supersymmetric) Standard Model, and thus its observational success, is preserved; (2) thanks to the enlarged scalar sector the RG improved one-loop effective potential is everywhere positive with a stable global minimum, thereby avoiding the notorious instability of the Standard Model vacuum; (3) the pseudo-Goldstone bosons resulting from spontaneous breaking of the SU(3)$_N$ symmetry are natural Dark M...

  12. The center for plant and microbial complex carbohydrates at the University of Georgia Complex Carbohydrate Research Center

    Energy Technology Data Exchange (ETDEWEB)

    Albersheim, P.; Darvill, A.

    1991-08-01

    Research from the Complex Carbohydrates Research Center at the University of Georgia is presented. Topics include: Structural determination of soybean isoflavones which specifically induce Bradyrhizobium japonicum nodD1 but not the nodYABCSUIJ operon; structural analysis of the lipopolysaccharides (LPSs) from symbiotic mutants of Bradyrhizobium japonicum; structural characterization of lipooligosaccharides from Bradyrhizobium japonicum that are required for the specific nodulation of soybean; structural characterization of the LPSs from R. Leguminosarum biovar phaseoli, the symbiont of bean; characterization of bacteroid-specific LPS epitopes in R. leguminosarum biovar viciae; analysis of the surface polysaccharides of Rhizobium meliloti mutants whose lipopolysaccharides and extracellular polysaccharides can have the same function in symbiosis; characterization of a polysaccharide produced by certain Bradyrhizobium japonicum strains within soybean nodules; structural analysis of a streptococcal adhesin polysaccharide receptor; conformational studies of xyloglucan, the role of the fucosylated side chain in surface-specific cellulose-xyloglucan interactions; the structure of an acylated glucosamine oligosaccharide signal molecule (nod factor) involved in the symbiosis of Rhizobium leguminosarum biovar viciae with its host Vicia sativa; investigating membrane responses induced by oligogalacturonides in cultured cells; the polygalacturonase inhibitor protein; characterization of the self-incompatability glycoproteins from Petunia hybrida; investigation of the cell wall polysaccharide structures of Arabidopsis thaliana; and the glucan inhibition of virus infection of tabacco.

  13. Regular Submanifolds in Conformal Space Qnp

    Institute of Scientific and Technical Information of China (English)

    Changxiong NIE; Chuanxi WU

    2012-01-01

    The authors study the regular submanifolds in the conformal space Qnp and introduce the submanifold theory in the conformal space Qnp.The first variation formula of the Willmore volume functional of pseudo-Riemannian submanifolds in the conformal space Qnp is given.Finally,the conformal isotropic submanifolds in the conformal space Qnp are classified.

  14. Organotin-catalyzed highly regioselective thiocarbonylation of nonprotected carbohydrates and synthesis of deoxy carbohydrates in a minimum number of steps.

    Science.gov (United States)

    Muramatsu, Wataru; Tanigawa, Satoko; Takemoto, Yuki; Yoshimatsu, Hirofumi; Onomura, Osamu

    2012-04-16

    Nonprotected carbohydrates: The catalytic regioselective thiocarbonylation of carbohydrates by using organotin dichloride under mild conditions was demonstrated. The reaction afforded various deoxy saccharides in high yields and excellent regioselectivity in a minimum number of steps. The regioselectivity of the thiocarbonylation is attributed to the intrinsic character of the carbohydrates based on the stereorelationship of their hydroxy groups (see scheme).

  15. Daily training with high carbohydrate availability increases exogenous carbohydrate oxidation during endurance cycling.

    Science.gov (United States)

    Cox, Gregory R; Clark, Sally A; Cox, Amanda J; Halson, Shona L; Hargreaves, Mark; Hawley, John A; Jeacocke, Nikki; Snow, Rodney J; Yeo, Wee Kian; Burke, Louise M

    2010-07-01

    We determined the effects of varying daily carbohydrate intake by providing or withholding carbohydrate during daily training on endurance performance, whole body rates of substrate oxidation, and selected mitochondrial enzymes. Sixteen endurance-trained cyclists or triathletes were pair matched and randomly allocated to either a high-carbohydrate group (High group; n = 8) or an energy-matched low-carbohydrate group (Low group; n = 8) for 28 days. Immediately before study commencement and during the final 5 days, subjects undertook a 5-day test block in which they completed an exercise trial consisting of a 100 min of steady-state cycling (100SS) followed by a 7-kJ/kg time trial on two occasions separated by 72 h. In a counterbalanced design, subjects consumed either water (water trial) or a 10% glucose solution (glucose trial) throughout the exercise trial. A muscle biopsy was taken from the vastus lateralis muscle on day 1 of the first test block, and rates of substrate oxidation were determined throughout 100SS. Training induced a marked increase in maximal citrate synthase activity after the intervention in the High group (27 vs. 34 micromol x g(-1) x min(-1), P < 0.001). Tracer-derived estimates of exogenous glucose oxidation during 100SS in the glucose trial increased from 54.6 to 63.6 g (P < 0.01) in the High group with no change in the Low group. Cycling performance improved by approximately 6% after training. We conclude that altering total daily carbohydrate intake by providing or withholding carbohydrate during daily training in trained athletes results in differences in selected metabolic adaptations to exercise, including the oxidation of exogenous carbohydrate. However, these metabolic changes do not alter the training-induced magnitude of increase in exercise performance.

  16. Functionalized carbon nanomaterials derived from carbohydrates.

    Science.gov (United States)

    Jagadeesan, Dinesh; Eswaramoorthy, Muthusamy

    2010-02-01

    A tremendous growth in the field of carbon nanomaterials has led to the emergence of carbon nanotubes, fullerenes, mesoporous carbon and more recently graphene. Some of these materials have found applications in electronics, sensors, catalysis, drug delivery, composites, and so forth. The high temperatures and hydrocarbon precursors involved in their synthesis usually yield highly inert graphitic surfaces. As some of the applications require functionalization of their inert graphitic surface with groups like -COOH, -OH, and -NH(2), treatment of these materials in oxidizing agents and concentrated acids become inevitable. More recent works have involved using precursors like carbohydrates to produce carbon nanostructures rich in functional groups in a single-step under hydrothermal conditions. These carbon nanostructures have already found many applications in composites, drug delivery, materials synthesis, and Li ion batteries. The review aims to highlight some of the recent developments in the application of carbohydrate derived carbon nanostructures and also provide an outlook of their future prospects.

  17. Carbohydrate plasma expanders for passive tumor targeting

    DEFF Research Database (Denmark)

    Hoffmann, Stefan; Caysa, Henrike; Kuntsche, Judith

    2013-01-01

    The objective of this study was to investigate the suitability of carbohydrate plasma volume expanders as a novel polymer platform for tumor targeting. Many synthetic polymers have already been synthesized for targeted tumor therapy, but potential advantages of these carbohydrates include...... inexpensive synthesis, constant availability, a good safety profile, biodegradability and the long clinical use as plasma expanders. Three polymers have been tested for cytotoxicity and cytokine activation in cell cultures and conjugated with a near-infrared fluorescent dye: hydroxyethyl starches (HES 200 k......Da and HES 450 kDa) and dextran (DEX 500 kDa). Particle size and molecular weight distribution were determined by asymmetric flow field-flow fractionation (AF4). The biodistribution was investigated non-invasively in nude mice using multispectral optical imaging. The most promising polymer conjugate...

  18. Conformal Patterson-Walker metrics

    CERN Document Server

    Hammerl, Matthias; Šilhan, Josef; Taghavi-Chabert, Arman; Žádník, Vojtěch

    2016-01-01

    The classical Patterson-Walker construction of a split-signature (pseudo-)Riemannian structure from a given torsion-free affine connection is generalized to a construction of a split-signature conformal structure from a given projective class of connections. A characterization of the induced structures is obtained. We achieve a complete description of Einstein metrics in the conformal class formed by the Patterson-Walker metric. Finally, we describe all symmetries of the conformal Patterson-Walker metric. In both cases we obtain descriptions in terms of geometric data on the original structure.

  19. Multimodal CARS microscopy of structured carbohydrate biopolymers

    OpenAIRE

    Slepkov, Aaron D.; Ridsdale, Andrew; Pegoraro, Adrian F.; Moffatt, Douglas J.; Stolow, Albert

    2010-01-01

    We demonstrate the utility of multimodal coherent anti-Stokes Raman scattering (CARS) microscopy for the study of structured condensed carbohydrate systems. Simultaneous second-harmonic generation (SHG) and spectrally-scanned CARS microscopy was used to elucidate structure, alignment, and density in cellulose cotton fibers and in starch grains undergoing rapid heat-moisture swelling. Our results suggest that CARS response of the O-H stretch region (3000 cm−1–3400 cm−1), together with the comm...

  20. Small-Molecule Carbohydrate-Based Immunostimulants.

    Science.gov (United States)

    Marzabadi, Cecilia H; Franck, Richard W

    2017-02-03

    In this review, we discuss small-molecule, carbohydrate-based immunostimulants that target Toll-like receptor 4 (TLR-4) and cluster of differentiation 1D (CD1d) receptors. The design and use of these molecules in immunotherapy as well as results from their use in clinical trials are described. How these molecules work and their utilization as vaccine adjuvants are also discussed. Future applications and extensions for the use of these analogues as therapeutic agents will be outlined.

  1. Crystallisation and crystal forms of carbohydrate derivatives

    Science.gov (United States)

    Lennon, Lorna

    This thesis is focused on the synthesis and solid state analysis of carbohydrate derivatives, including many novel compounds. Although the synthetic chemistry surrounding carbohydrates is well established in the literature, the crystal chemistry of carbohydrates is less well studied. Therefore this research aims to improve understanding of the solid state properties of carbohydrate derivatives through gaining more information on their supramolecular bonding. Chapter One focuses on an introduction to the solid state of organic compounds, with a background to crystallisation, including issues that can arise during crystal growth. Chapter Two is based on glucopyranuronate derivatives which are understudied in terms of their solid state forms. This chapter reports on the formation of novel glucuronamides and utilising the functionality of the amide bond for crystallisation. TEMPO oxidation was completed to form glucopyranuronates by oxidation of the primary alcohol groups of glucosides to the carboxylic acid derivatives, to increase functionality for enhanced crystal growth. Chapter Three reports on the synthesis of glucopyranoside derivatives by O-glycosylation reactions and displays crystal structures, including a number of previously unsolved acetate protected and deprotected crystal structures. More complex glycoside derivatives were also researched in an aim to study the resultant supramolecular motifs. Chapter Four contains the synthesis of aryl cellobioside derivatives including the novel crystal structures that were solved for the acetate protected and deprotected compounds. Research was carried out to determine if 1-deoxycellodextrins could act as putative isostructures for cellulose. Our research displays the presence of isostructural references with 1-deoxycellotriose shown to be similar to cellulose III11, 1-deoxycellotetraose correlates with cellulose IV11 and 1-deoxycellopentose shows isostructurality similar to that of cellulose II. Chapter Five contains

  2. Direct synthesis of methyl phosphoramidates in carbohydrates.

    Science.gov (United States)

    Dhurandhare, Vijay M; Mishra, Girija Prasad; Lam, Sarah; Wang, Cheng-Chung

    2015-09-28

    A direct installation of a methyl phosphoramidate group by using methyl benzylphosphoramidochloridate into carbohydrates and amino acid is described. This one-step synthesis is efficient for both primary and secondary alcohols and exhibited excellent regioselectivity and functional group compatibility. Formation of a single diastereomer is observed in certain cases. The N-benzyl protecting group on methyl phosphoramidates is easily removed under mild conditions.

  3. Hearing Loss, Dizziness, and Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    Albernaz, Pedro L. Mangabeira

    2015-07-01

    Full Text Available Introduction Metabolic activity of the inner ear is very intense, and makes it sensitive to changes in the body homeostasis. This study involves a group of patients with inner ear disorders related to carbohydrate metabolism disturbances, including hearing loss, tinnitus, dizziness, and episodes of vertigo. Objectives To describe the symptoms of metabolic inner ear disorders and the examinations required to establish diagnoses. These symptoms are often the first to allow for an early diagnosis of metabolic disorders and diabetes. Methods Retrospective study of 376 patients with inner ear symptoms suggestive of disturbances of carbohydrate metabolism. The authors present patientś clinical symptoms and clinical evaluations, with emphasis on the glucose and insulin essays. Results Authors based their conclusions on otolaryngological findings, diagnostic procedures and treatment principles. They found that auditory and vestibular symptoms usually occur prior to other manifestations of metabolic changes, leading to an early diagnosis of hyperinsulinemia, intestinal sugar malabsorption or diabetes. Previously undiagnosed diabetes mellitus type II was found in 39 patients. Conclusions The identification of carbohydrate metabolism disturbances is important not only to minimize the patients' clinical symptoms, but also to help maintain their general health.

  4. UV-B radiation does not limit carbohydrate level and carbohydrate metabolism in cucumber leaves

    Directory of Open Access Journals (Sweden)

    Magdalena Rybus-Zając

    2014-08-01

    Full Text Available Cucumber is a vegetable exhibiting relatively high sensitivity to environmental stress factors. When it is grown outdoors, from early stages of development there is a real risk of exposure to elevated UV-B radiation. In order to explain the effects of time-dependent UV-B doses on carbohydrate level and metabolism, the photosynthetic activity, accumulation of carbohydrates and activities of carbohydrate-related enzymes were determined in the cucumber leaves. Elevated UV-B radiation led to an increase in the rate of photosynthesis, which was reflected by an increase in SPAD values. Higher photosynthetic activity resulted in an increase in levels of soluble sugars. In view of the above-mentioned results, radiation stress led to a UV-B time-dependent dose increase in the activity of two enzymes decomposing carbohydrate: invertase and glucosidase. Our results suggest that the exposure of cucumber plants to supplemental UV-B doses does not limit the availability of the photoassimilate. Carbohydrates are required to provide not only respiratory energy for protection, maintenance (and repair of plant activity and structure, but also provide biosynthetic carbon skeletons for secondary metabolite synthesis

  5. Logarithmic conformal field theory

    Science.gov (United States)

    Gainutdinov, Azat; Ridout, David; Runkel, Ingo

    2013-12-01

    Conformal field theory (CFT) has proven to be one of the richest and deepest subjects of modern theoretical and mathematical physics research, especially as regards statistical mechanics and string theory. It has also stimulated an enormous amount of activity in mathematics, shaping and building bridges between seemingly disparate fields through the study of vertex operator algebras, a (partial) axiomatisation of a chiral CFT. One can add to this that the successes of CFT, particularly when applied to statistical lattice models, have also served as an inspiration for mathematicians to develop entirely new fields: the Schramm-Loewner evolution and Smirnov's discrete complex analysis being notable examples. When the energy operator fails to be diagonalisable on the quantum state space, the CFT is said to be logarithmic. Consequently, a logarithmic CFT is one whose quantum space of states is constructed from a collection of representations which includes reducible but indecomposable ones. This qualifier arises because of the consequence that certain correlation functions will possess logarithmic singularities, something that contrasts with the familiar case of power law singularities. While such logarithmic singularities and reducible representations were noted by Rozansky and Saleur in their study of the U (1|1) Wess-Zumino-Witten model in 1992, the link between the non-diagonalisability of the energy operator and logarithmic singularities in correlators is usually ascribed to Gurarie's 1993 article (his paper also contains the first usage of the term 'logarithmic conformal field theory'). The class of CFTs that were under control at this time was quite small. In particular, an enormous amount of work from the statistical mechanics and string theory communities had produced a fairly detailed understanding of the (so-called) rational CFTs. However, physicists from both camps were well aware that applications from many diverse fields required significantly more

  6. Some Progress in Conformal Geometry

    Directory of Open Access Journals (Sweden)

    Sun-Yung A. Chang

    2007-12-01

    Full Text Available This is a survey paper of our current research on the theory of partial differential equations in conformal geometry. Our intention is to describe some of our current works in a rather brief and expository fashion. We are not giving a comprehensive survey on the subject and references cited here are not intended to be complete. We introduce a bubble tree structure to study the degeneration of a class of Yamabe metrics on Bach flat manifolds satisfying some global conformal bounds on compact manifolds of dimension 4. As applications, we establish a gap theorem, a finiteness theorem for diffeomorphism type for this class, and diameter bound of the $sigma_2$-metrics in a class of conformal 4-manifolds. For conformally compact Einstein metrics we introduce an eigenfunction compactification. As a consequence we obtain some topological constraints in terms of renormalized volumes.

  7. Graphene-based conformal devices.

    Science.gov (United States)

    Park, Yong Ju; Lee, Seoung-Ki; Kim, Min-Seok; Kim, Hyunmin; Ahn, Jong-Hyun

    2014-08-26

    Despite recent progress in bendable and stretchable thin-film transistors using novel designs and materials, the development of conformal devices remains limited by the insufficient flexibility of devices. Here, we demonstrate the fabrication of graphene-based conformal and stretchable devices such as transistor and tactile sensor on a substrate with a convoluted surface by scaling down the device thickness. The 70 nm thick graphene-based conformal devices displayed a much lower bending stiffness than reported previously. The demonstrated devices provided excellent conformal coverage over an uneven animal hide surface without the need for an adhesive. In addition, the ultrathin graphene devices formed on the three-dimensionally curved animal hide exhibited stable electrical characteristics, even under repetitive bending and twisting. The advanced performance and flexibility demonstrated here show promise for the development and adoption of wearable electronics in a wide range of future applications.

  8. National Automated Conformity Inspection Process -

    Data.gov (United States)

    Department of Transportation — The National Automated Conformity Inspection Process (NACIP) Application is intended to expedite the workflow process as it pertains to the FAA Form 81 0-10 Request...

  9. Solution conformation of C-linked antifreeze glycoprotein analogues and modulation of ice recrystallization.

    Science.gov (United States)

    Tam, Roger Y; Rowley, Christopher N; Petrov, Ivan; Zhang, Tianyi; Afagh, Nicholas A; Woo, Tom K; Ben, Robert N

    2009-11-01

    Antifreeze glycoproteins (AFGPs) are a unique class of proteins that are found in many organisms inhabiting subzero environments and ensure their survival by preventing ice growth in vivo. During the last several years, our laboratory has synthesized functional C-linked AFGP analogues (3 and 5) that possess custom-tailored antifreeze activity suitable for medical, commercial, and industrial applications. These compounds are potent inhibitors of ice recrystallization and do not exhibit thermal hysteresis. The current study explores how changes in the length of the amide-containing side chain between the carbohydrate moiety and the polypeptide backbone in 5 influences ice recrystallization inhibition (IRI) activity. Analogue 5 (n = 3, where n is the number of carbons in the side chain) was a potent inhibitor of ice recrystallization, while 4, 6, and 7 (n = 4, 2, and 1, respectively) exhibited no IRI activity. The solution conformation of the polypeptide backbone in C-linked AFGP analogues 4-7 was examined using circular dichroism (CD) spectroscopy. The results suggested that all of the analogues exhibit a random coil conformation in solution and that the dramatic increase in IRI activity observed with 5 is not due to a change in long-range solution conformation. Variable-temperature (1)H NMR studies on truncated analogues 26-28 failed to elucidate the presence of persistent intramolecular bonds between the amide in the side chain and the peptide backbone. Molecular dynamics simulations performed on these analogues also failed to show persistent intramolecular hydrogen bonds. However, the simulations did indicate that the side chain of IRI-active analogue 26 (n = 3) adopts a unique short-range solution conformation in which it is folded back onto the peptide backbone, orienting the more hydrophilic face of the carbohydrate moiety away from the bulk solvent. In contrast, the solution conformation of IRI-inactive analogues 25, 27, and 28 had fully extended side chains

  10. Carbohydrate-protein interactions and their biosensing applications.

    Science.gov (United States)

    Zeng, Xiangqun; Andrade, Cesar A S; Oliveira, Maria D L; Sun, Xue-Long

    2012-04-01

    Carbohydrate recognition is clearly present throughout nature, playing a major role in the initial attachment of one biological entity to another. The important question is whether these prevalent interactions could provide a real suitable alternative to the use of antibodies or nucleic acid for detection and identification. Currently, examples of carbohydrates being employed in biological detection systems are limited. The challenges of using carbohydrate recognition for detection mainly come from the weak affinity of carbohydrate-protein interactions, the lack of versatile carbohydrate scaffolds with well-defined structures, and the less developed high-information-content, real-time, and label-free assay technology. In this review, we focus on discussing the characteristics of carbohydrate-protein interactions in nature and the methods for carbohydrate immobilization based on surface coupling chemistry in terms of their general applicability for developing carbohydrate- and lectin-based label-free sensors. Furthermore, examples of innovative design of multivalent carbohydrate-protein interactions for sensor applications are given. We limit our review to show the feasibility of carbohydrate and lectin as recognition elements for label-free sensor development in several representative cases to formulate a flexible platform for their use as recognition elements for real-world biosensor applications.

  11. A step towards personalized sports nutrition: carbohydrate intake during exercise.

    Science.gov (United States)

    Jeukendrup, Asker

    2014-05-01

    There have been significant changes in the understanding of the role of carbohydrates during endurance exercise in recent years, which allows for more specific and more personalized advice with regard to carbohydrate ingestion during exercise. The new proposed guidelines take into account the duration (and intensity) of exercise and advice is not restricted to the amount of carbohydrate; it also gives direction with respect to the type of carbohydrate. Studies have shown that during exercise lasting approximately 1 h in duration, a mouth rinse or small amounts of carbohydrate can result in a performance benefit. A single carbohydrate source can be oxidized at rates up to approximately 60 g/h and this is the recommendation for exercise that is more prolonged (2-3 h). For ultra-endurance events, the recommendation is higher at approximately 90 g/h. Carbohydrate ingested at such high ingestion rates must be a multiple transportable carbohydrates to allow high oxidation rates and prevent the accumulation of carbohydrate in the intestine. The source of the carbohydrate may be a liquid, semisolid, or solid, and the recommendations may need to be adjusted downward when the absolute exercise intensity is low and thus carbohydrate oxidation rates are also low. Carbohydrate intake advice is independent of body weight as well as training status. Therefore, although these guidelines apply to most athletes, they are highly dependent on the type and duration of activity. These new guidelines may replace the generic existing guidelines for carbohydrate intake during endurance exercise.

  12. CONFORMANCE IMPROVEMENT USING GELS

    Energy Technology Data Exchange (ETDEWEB)

    Randall S. Seright

    2004-09-30

    This report describes work performed during the third and final year of the project, ''Conformance Improvement Using Gels.'' Corefloods revealed throughput dependencies of permeability reduction by polymers and gels that were much more prolonged during oil flow than water flow. This behavior was explained using simple mobility ratio arguments. A model was developed that quantitatively fits the results and predicts ''clean up'' times for oil productivity when production wells are returned to service after application of a polymer or gel treatment. X-ray computed microtomography studies of gels in strongly water-wet Berea sandstone and strongly oil-wet porous polyethylene suggested that oil penetration through gel-filled pores occurs by a gel-dehydration mechanism, rather than gel-ripping or gel-displacement mechanisms. In contrast, analysis of data from the University of Kansas suggests that the gel-ripping or displacement mechanisms are more important in more permeable, strongly water-wet sandpacks. These findings help to explain why aqueous gels can reduce permeability to water more than to oil under different conditions. Since cement is the most commonly used material for water shutoff, we considered when gels are preferred over cements. Our analysis and experimental results indicated that cement cannot be expected to completely fill (top to bottom) a vertical fracture of any width, except near the wellbore. For vertical fractures with apertures less than 4 mm, the cement slurry will simply not penetrate very far into the fracture. For vertical fractures with apertures greater than 4 mm, the slurry may penetrate a substantial distance into the bottom part of the fracture. However, except near the wellbore, the upper part of the fracture will remain open due to gravity segregation. We compared various approaches to plugging fractures using gels, including (1) varying polymer content, (2) varying placement (extrusion) rate

  13. To conform or not to conform: spontaneous conformity diminishes the sensitivity to monetary outcomes.

    Science.gov (United States)

    Yu, Rongjun; Sun, Sai

    2013-01-01

    When people have different opinions in a group, they often adjust their own attitudes and behaviors to match the group opinion, known as social conformity. The affiliation account of normative conformity states that people conform to norms in order to 'fit in', whereas the accuracy account of informative conformity posits that the motive to learn from others produces herding. Here, we test another possibility that following the crowd reduces the experienced negative emotion when the group decision turns out to be a bad one. Using event related potential (ERP) combined with a novel group gambling task, we found that participants were more likely to choose the option that was predominately chosen by other players in previous trials, although there was little explicit normative pressure at the decision stage and group choices were not informative. When individuals' choices were different from others, the feedback related negativity (FRN), an ERP component sensitive to losses and errors, was enhanced, suggesting that being independent is aversive. At the outcome stage, the losses minus wins FRN effect was significantly reduced following conformity choices than following independent choices. Analyses of the P300 revealed similar patterns both in the response and outcome period. Our study suggests that social conformity serves as an emotional buffer that protects individuals from experiencing strong negative emotion when the outcomes are bad.

  14. [Malabsorption of carbohydrates in children (author's transl)].

    Science.gov (United States)

    Vázquez, C; Escobar, H; Polanco, I; Codoceo, R; Vitoria, J C

    1975-01-01

    Physiological bases of digestion and absorption of carbohydrates are reviewed, as a preliminary step, in order to draw a general scheme of its patholophysiology. Clasification of different types of carbohydrate malabsorption is presented. Various exploration methods are discussed in terms of autors' own experiences. Relationship between a sugar screening test, faecal lactic acid contents and a simplified lactose tolerance test, is described in detail. Systematic diagnoses of these diseases are established. Different clinical pictures are reviewed. It is not yet well defined if a starch malabsorption can be caused by either a primary or secondary duodenal amylase deficiency. The clinical forms of congenital sucrose-isomaltose intolerance may be more attenuated than its classical form; incertain cases, secondary sucrose intolerance may also be present due to mucosa anatomic lesions. Maltose malabsorption has no clinical implications. As compared to other alpha-glycosidades, the trehalase activity has been not more affected by not using trehalose in feeding. Primary congenital lactase deficiency is not frequent, whereas secondary forms as much more usual and appear, in primary malabsorption syndromes and in the coeliac disease, very often along with clinical tolerance to lactose. In Spain, lactose nonabsorbers in 16.5% for adults 11.2% for adolescents and 18.3% for children, meaning, that it is being favored by environmental factors in the latter. The unspecified sugar malabsorption during the child's first year is still the most frequent cause of carbohydrate intolerance in children and, although certain progress has been achieved in its diagnosis and therapy, its pathogenic mechanism is not satisfactorily known yet.

  15. Carbohydrate metabolism of rats with biliary obstruction.

    Directory of Open Access Journals (Sweden)

    Kim,Hitoshi

    1990-08-01

    Full Text Available Carbohydrate metabolism of rats with obstructive jaundice caused by bile duct ligation was studied by intravenous glucose tolerance test (IVGTT and by liver perfusion. The altered levels of carbohydrate-metabolizing enzyme were examined in relation to the glucose metabolism of the cholestatic rats. In the IVGTT, the rate of fractional glucose removal was increased with increases in plasma insulin and glucagon and with a decrease in non-esterified fatty acid. In liver perfusion, neither the glucose uptake nor insulin extraction by the whole liver of icteric rats was different from the control. The increased rate of glucose removal in IVGTT may be due to enhanced glucose utilization by peripheral tissues resulting from hypersecretion of insulin. In liver perfusate supplemented with glucose, a decrease in the glucose uptake per unit liver weight was observed in relation to the lowered glucokinase activity. Formation of glycogen from glucose and of glucose from lactate was also impaired, indicating inhibition of the gluconeogenic system or relative hyperfunction of the glycolytic system, which may further contribute to the reduction in glycogen content. These metabolic disorders correlated well with the changes in activities of key carbohydrate-metabolizing enzymes, which showed a characteristic pattern consistent with the loss of differentiated hepatic functions. Uptake of glucose and its conversion to glycogen were reduced in the cholestatic liver in close association with altered activities of some of related enzymes. However, due to increased utilization by the peripheral tissues, the total amount of glucose utilized in the whole rat was not reduced.

  16. Carbohydrate nanotechnology: hierarchical assembly using nature's other information carrying biopolymers.

    Science.gov (United States)

    Han, Xu; Zheng, Yeting; Munro, Catherine J; Ji, Yiwen; Braunschweig, Adam B

    2015-08-01

    Despite their central role in directing some of the most complex biological processes, carbohydrates--nature's other information carrying biopolymer--have been largely ignored as building blocks for synthetic hierarchical assemblies. The non-stoichiometric binding and astronomical diversity characteristic of carbohydrates could lead to tantalizingly complex assembly algorithms, but these attributes simultaneously increase the difficulty of preparing carbohydrate assemblies and anticipating their behavior. Convergences in biotechnology, nanotechnology, polymer chemistry, surface science, and supramolecular chemistry have led to many recent important breakthroughs in glycan microarrays and synthetic carbohydrate receptors, where the idiosyncrasies of carbohydrate structure and binding are increasingly considered. We hope to inspire more researchers to consider carbohydrate structure, diversity, and binding as attractive tools for constructing synthetic hierarchical assemblies.

  17. Multimodal CARS microscopy of structured carbohydrate biopolymers

    Science.gov (United States)

    Slepkov, Aaron D.; Ridsdale, Andrew; Pegoraro, Adrian F.; Moffatt, Douglas J.; Stolow, Albert

    2010-01-01

    We demonstrate the utility of multimodal coherent anti-Stokes Raman scattering (CARS) microscopy for the study of structured condensed carbohydrate systems. Simultaneous second-harmonic generation (SHG) and spectrally-scanned CARS microscopy was used to elucidate structure, alignment, and density in cellulose cotton fibers and in starch grains undergoing rapid heat-moisture swelling. Our results suggest that CARS response of the O-H stretch region (3000 cm−1–3400 cm−1), together with the commonly-measured C-H stretch (2750 cm−1–2970 cm−1) and SHG provide potentially important structural information and contrast in these materials. PMID:21258555

  18. Multimodal CARS microscopy of structured carbohydrate biopolymers.

    Science.gov (United States)

    Slepkov, Aaron D; Ridsdale, Andrew; Pegoraro, Adrian F; Moffatt, Douglas J; Stolow, Albert

    2010-11-08

    We demonstrate the utility of multimodal coherent anti-Stokes Raman scattering (CARS) microscopy for the study of structured condensed carbohydrate systems. Simultaneous second-harmonic generation (SHG) and spectrally-scanned CARS microscopy was used to elucidate structure, alignment, and density in cellulose cotton fibers and in starch grains undergoing rapid heat-moisture swelling. Our results suggest that CARS response of the O-H stretch region (3000 cm(-1)-3400 cm(-1)), together with the commonly-measured C-H stretch (2750 cm(-1)-2970 cm(-1)) and SHG provide potentially important structural information and contrast in these materials.

  19. Carbohydrates/nucleosides/RNA-DNA-ligand interactions

    Energy Technology Data Exchange (ETDEWEB)

    Kaptein, R.; McConnell, B.; Serianni, A.S.; Silks, L.A. III

    1994-12-01

    Carbohydrate and nucleotide structural determination using modern spectroscopic techniques is dependent on our ability to label oligonucleotides and oligosaccharides with stable isotopes. Uniform Carbon 13 and Nitrogen 15 labeling of oligonucleotides is important to present-day efforts, which are focused on determining the structure of relatively small oligosaccharides and oligonucleotides, which form the elements of larger structures. Because of the relatively recent interest in three-dimensional structure, the development of techniques used to label them has lagged behind parallel techniques used to label peptides and proteins. Therefore, this group`s discussion focused primarily on problems faced today in obtaining oligonucleotides labeled uniformly with carbon 13 and nitrogen 15.

  20. A high-power carbohydrate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Ragnar [SuFuCell AB, Bytaregatan 23, SE 222 21 Lund (Sweden); Folkesson, Boerje [Bronsaaldersvaegen 21, SE-226 54 Lund (Sweden); Spaziante, Placido M. [Cellennium Co., Ltd., 14th Floor Gypsum Metropolitan Tower, 539 Sri Ayudhaya Rd., Bangkok 10400 (Thailand); Veerasai, Waret [Chemistry Department, Faculty of Science, Mahidol University, Bangkok 10400 (Thailand); Exell, Robert H.B. [Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 91 Prachauthit Rd., Bangmod, Tungkru, Bangkok 10140 (Thailand)

    2006-04-01

    This paper reports the development of a fuel cell consisting of a vanadium flow battery in which the vanadium ions are reduced by sugar (from a carbohydrate) to oxidation state +3 on one side of a membrane, and are oxidized to state +5 on the other side by oxygen. The theoretical upper limit to the conversion efficiency of the energy in sugar by this method under standard conditions is 54%. We have obtained efficiencies up to 45% in our laboratory tests. This way of using biomass for electricity production avoids the Carnot cycle losses in heat engines. (author)

  1. 40 CFR 93.154 - Conformity analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Conformity analysis. 93.154 Section 93...) DETERMINING CONFORMITY OF FEDERAL ACTIONS TO STATE OR FEDERAL IMPLEMENTATION PLANS Determining Conformity of General Federal Actions to State or Federal Implementation Plans § 93.154 Conformity analysis. Any...

  2. Group Cohesiveness, Deviation, Stress, and Conformity

    Science.gov (United States)

    1993-08-11

    Yuke1son, Weinberg & Jackson , 1984; Carron & Chelladurai, 1981). The classical studies of jury dynamics began to appear within the field of...1987), individuation was negatively correlated with conformity (Santee & Maslach , 1982). Conformity Paradi&ms Host studies of conformity have...appear to affect conformity rates independently of attraction . However, later ~tudies by Dittes and Kelley (1956) and Jackson and Saltzstein (1958

  3. Conformal Gravity Rotation Curves with a Conformal Higgs Halo

    CERN Document Server

    Horne, Keith

    2016-01-01

    We discuss the effect of a conformally coupled Higgs field on conformal gravity (CG) predictions for the rotation curves of galaxies. The Mannheim-Kazanas (MK) metric is a valid vacuum solution of CG's 4-th order Poisson equation only if the Higgs field has a particular radial profile, S(r)=S_0 a/(r+a), decreasing from S_0 at r=0 with radial scale length a. Since particle rest masses scale with S(r)/S_0, their world lines do not follow time-like geodesics of the MK metric g_{\\mu\

  4. New potentials for conformal mechanics

    CERN Document Server

    Papadopoulos, G

    2012-01-01

    We show that V=\\alpha x^2+\\beta x^{-2} arises as a potential of 1-dimensional conformal theories. This class of conformal models includes the DFF model \\alpha=0 and the harmonic oscillator \\beta=0. The construction is based on a different embedding of the conformal symmetry group into the time re-parameterizations from that of the DFF model and its generalizations. Depending on the range of the couplings $\\alpha, \\beta$, these models can have a ground state and a well-defined energy spectrum, and exhibit either a $SL(2,\\bR)$ or a SO(3) conformal symmetry. The latter group can also be embedded in Diff(S^1). We also present several generalizations of these models which include the Calogero models with harmonic oscillator couplings and non-linear models with suitable metric and potential couplings. In addition, we give the conditions on the couplings for a class of gaugetheories to admit a SL(2,\\bR) or SO(3) conformal symmetry. We present examples of such systems with general gauge groups and global symmetries t...

  5. Differences among Elite Female Rowers Regarding Carbohydrate Consumption at Rest

    OpenAIRE

    BADAU, Dana; TOMESCU, VALERIU; BADAU, Adela; MARTIN, Ștefan Adrian

    2016-01-01

    Backround: The objective of this study was interpreting the reported differences within carbohydrate consumption at rest, in female rowing groups. Method: We conducted a cross-sectional study, on a group of elite rowing athletes, monitoring carbohydrate consumption at rest. 34 subjects, divided in 3 groups of activities (senior, youth, junior) took part in this study being monitored through Cosmed Quark CPET device. Results: The average amount of carbohydrates consumed at rest among the group...

  6. Structure-function relations of carbohydrates by neoglycolipid arrays.

    Science.gov (United States)

    Huang, Gang-Liang; Huang, Hua-Liang; Zhang, Hou-Cheng; Wang, Peng-George

    2006-06-01

    The work presented herein is a new noncovalent glycoarray assembly method for microplates created by simply mixing together a carbohydrate and a tetradecylamine. alpha-D-Mannopyranoside, alpha-D-glucopyranoside, and alpha-D-galactopyranoside were utilized in model studies and product formations were detected by lectin binding. The method can be extended to study the steric hindrance effect of carbohydrate-protein interactions, namely the structure-function relations of carbohydrates.

  7. CARBOHYDRATE INGESTION AND EXERCISE: EFFECTS ON METABOLISM AND PERFORMANCE

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@KEY POINTS ■ Carbohydrate is the preferred fuel for most competitive sports;an inadequate supply of carbohydrate in the body often leads to poor performance. ■ Carbohydrate ingestion during exercise increases blood glucose availability and maintains the ability of the body to use carbohydrate as fuel during exercise.When carbohydrate is consumed during exercise,glucose uptake by muscles is increased,and the breakdown of glycogen in the liver into blood glucose is reduced,thus saving liver glycogen until late in exercise.The use of muscle glycogen for energy is generally unaffected by carbohydrate feeding.However,during prolonged running,the breakdown of muscle glycogen may be slowed because the supply of blood glucose is improved when carbohydrate is consumed.These metabolic responses underlie the performance benefit that accompanies carbohydrate ingestion during exercise. ■ There are some minor differences among glucose,sucrose,and maltodextrins in their effects on metabolism,but each of them can enhance performance when ingested in the appropriate quantity during exercise.Fructose alone is not an effective carbohydrate supplement because of its slow absorption and slow conversion by the body to glucose,but when small amounts of fructose are combined with other carbohydrates,fructose can be beneficial. ■ Ingesting carbohydrate at a rate of 30-60 grams per hour can improve exercise erformance.A good way to achieve this carbohydrate intake is to consume 600-to-1200 ml(20-to-40 oz)of a sports drink during each hour of exercise.Consuming carbohydrate in a beverage provides an added benefit of preventing potentially harmful effects of dehydration on performance.

  8. Carbohydrate-active enzymes from pigmented Bacilli: a genomic approach to assess carbohydrate utilization and degradation

    Directory of Open Access Journals (Sweden)

    Henrissat Bernard

    2011-09-01

    Full Text Available Abstract Background Spore-forming Bacilli are Gram-positive bacteria commonly found in a variety of natural habitats, including soil, water and the gastro-intestinal (GI-tract of animals. Isolates of various Bacillus species produce pigments, mostly carotenoids, with a putative protective role against UV irradiation and oxygen-reactive forms. Results We report the annotation of carbohydrate active enzymes (CAZymes of two pigmented Bacilli isolated from the human GI-tract and belonging to the Bacillus indicus and B. firmus species. A high number of glycoside hydrolases (GHs and carbohydrate binding modules (CBMs were found in both isolates. A detailed analysis of CAZyme families, was performed and supported by growth data. Carbohydrates able to support growth as the sole carbon source negatively effected carotenoid formation in rich medium, suggesting that a catabolite repression-like mechanism controls carotenoid biosynthesis in both Bacilli. Experimental results on biofilm formation confirmed genomic data on the potentials of B. indicus HU36 to produce a levan-based biofilm, while mucin-binding and -degradation experiments supported genomic data suggesting the ability of both Bacilli to degrade mammalian glycans. Conclusions CAZy analyses of the genomes of the two pigmented Bacilli, compared to other Bacillus species and validated by experimental data on carbohydrate utilization, biofilm formation and mucin degradation, suggests that the two pigmented Bacilli are adapted to the intestinal environment and are suited to grow in and colonize the human gut.

  9. The least-cost low-carbohydrate diet is expensive.

    Science.gov (United States)

    Raffensperger, John F

    2008-01-01

    This article describes the use of operations research methods to study the minimum possible cost of a low-carbohydrate diet. The study compares this cost to the minimum cost of a diet with no limitation on carbohydrate. The rationale for this study is the popularity of the low-carbohydrate diets and their perceived high cost. The method used was an operations research approach to find a set of least cost diets, varying the required carbohydrate. This method was chosen to avoid potential concerns with real diets that may be nutritionally deficient or could be had for a lower cost. The major finding is that the cheapest possible low-carbohydrate diet costs about triple the cost of the cheapest diet with no constraint on carbohydrate. Furthermore, the minimum cost of a diet low in both carbohydrate and fat is 5 to 10 times the cost of the cheapest diet, depending on the relative amounts of these nutrients. As carbohydrate and fat are constrained, cost increases dramatically and nonlinearly. The study identifies which nutrients had the greatest effect on cost for a low-carbohydrate and low-fat diet.

  10. Lectures on Conformal Field Theory

    CERN Document Server

    Qualls, Joshua D

    2015-01-01

    These lectures notes are based on courses given at National Taiwan University, National Chiao-Tung University, and National Tsing Hua University in the spring term of 2015. Although the course was offered primarily for graduate students, these lecture notes have been prepared for a more general audience. They are intended as an introduction to conformal field theories in various dimensions, with applications related to topics of particular interest: topics include the conformal bootstrap program, boundary conformal field theory, and applications related to the AdS/CFT correspondence. We assume the reader to be familiar with quantum mechanics at the graduate level and to have some basic knowledge of quantum field theory. Familiarity with string theory is not a prerequisite for this lectures, although it can only help.

  11. Conformal Anomalies and Gravitational Waves

    CERN Document Server

    Meissner, Krzysztof A

    2016-01-01

    We argue that the presence of conformal anomalies in gravitational theories can lead to observable modifications to Einstein's equations via the induced anomalous effective actions, whose non-localities can overwhelm the smallness of the Planck scale. The fact that no such effects have been seen in recent cosmological or gravitational wave observations therefore imposes strong restrictions on the field content of possible extensions of Einstein's theory: all viable theories should have vanishing conformal anomalies. We then show that, among presently known theories, a complete cancellation of conformal anomalies in $D=4$ for both the $C^2$ invariant and the Euler (Gauss-Bonnet) invariant $E_4$ can only be achieved for $N$-extended supergravities with $N\\geq 5$, as well as for M theory compactified to four dimensions.

  12. Conformal Mapping for Multiple Terminals

    CERN Document Server

    Wang, Weimin; Wang, Qiang; Ren, Hao

    2015-01-01

    Conformal mapping is an important mathematical tool in many physical and engineering fields, especially in electrostatics, fluid mechanics, classical mechanics, and transformation optics. However in the existing textbooks and literatures, it is only adopted to solve the problems which have only two terminals. Two terminals with electric potential differences, pressure difference, optical path difference, etc., can be mapped conformally onto a solvable structure, e.g., a rectangle, where the two terminals are mapped onto two opposite edges of the rectangle. Here we show a conformal mapping method for multiple terminals, which is more common in practical applications. Through accurate analysis of the boundary conditions, additional terminals or boundaries are folded in the inner of the mapped rectangle. Then the solution will not be influenced. The method is described in several typical situations and two application examples are detailed. The first example is an electrostatic actuator with three electrodes. A ...

  13. Renyi entropy and conformal defects

    Energy Technology Data Exchange (ETDEWEB)

    Bianchi, Lorenzo [Humboldt-Univ. Berlin (Germany). Inst. fuer Physik; Hamburg Univ. (Germany). II. Inst. fuer Theoretische Physik; Meineri, Marco [Scuola Normale Superiore, Pisa (Italy); Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada); Istituto Nazionale di Fisica Nucleare, Pisa (Italy); Myers, Robert C. [Perimeter Institute for Theoretical Physics, Waterloo, ON (Canada); Smolkin, Michael [California Univ., Berkely, CA (United States). Center for Theoretical Physics and Department of Physics

    2016-04-18

    We propose a field theoretic framework for calculating the dependence of Renyi entropies on the shape of the entangling surface in a conformal field theory. Our approach rests on regarding the corresponding twist operator as a conformal defect and in particular, we define the displacement operator which implements small local deformations of the entangling surface. We identify a simple constraint between the coefficient defining the two-point function of the displacement operator and the conformal weight of the twist operator, which consolidates a number of distinct conjectures on the shape dependence of the Renyi entropy. As an example, using this approach, we examine a conjecture regarding the universal coefficient associated with a conical singularity in the entangling surface for CFTs in any number of spacetime dimensions. We also provide a general formula for the second order variation of the Renyi entropy arising from small deformations of a spherical entangling surface, extending Mezei's results for the entanglement entropy.

  14. Renewable Hydrogen Carrier — Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

    Directory of Open Access Journals (Sweden)

    Y.-H. Percival Zhang

    2011-01-01

    Full Text Available The hydrogen economy presents an appealing energy future but its implementation must solve numerous problems ranging from low-cost sustainable production, high-density storage, costly infrastructure, to eliminating safety concern. The use of renewable carbohydrate as a high-density hydrogen carrier and energy source for hydrogen production is possible due to emerging cell-free synthetic biology technology—cell-free synthetic pathway biotransformation (SyPaB. Assembly of numerous enzymes and co-enzymes in vitro can create complicated set of biological reactions or pathways that microorganisms or catalysts cannot complete, for example, C6H10O5 (aq + 7 H2O (l à 12 H2 (g + 6 CO2 (g (PLoS One 2007, 2:e456. Thanks to 100% selectivity of enzymes, modest reaction conditions, and high-purity of generated hydrogen, carbohydrate is a promising hydrogen carrier for end users. Gravimetric density of carbohydrate is 14.8 H2 mass% if water can be recycled from proton exchange membrane fuel cells or 8.33% H2 mass% without water recycling. Renewable carbohydrate can be isolated from plant biomass or would be produced from a combination of solar electricity/hydrogen and carbon dioxide fixation mediated by high-efficiency artificial photosynthesis mediated by SyPaB. The construction of this carbon-neutral carbohydrate economy would address numerous sustainability challenges, such as electricity and hydrogen storage, CO2 fixation and long-term storage, water conservation, transportation fuel production, plus feed and food production.

  15. CARBOHYDRATE INTAKE CONSIDERATIONS FOR YOUNG ATHLETES

    Directory of Open Access Journals (Sweden)

    Veronica Montfort-Steiger

    2007-09-01

    Full Text Available Good nutritional practices are important for exercise performance and health during all ages. Athletes and especially growing children engaged in heavy training have higher energy and nutrient requirements compared to their non-active counterparts. Scientific understanding of sports nutrition for the young athlete is lacking behind the growing number of young athletes engaged in sports. Most of the sports nutrition recommendations given to athletic children and adolescents are based on adult findings due to the deficiency in age specific information in young athletes. Therefore, this review reflects on child specific sports nutrition, particularly on carbohydrate intake and metabolism that distinguishes the child athlete from the adult athlete. Children are characterised to be in an insulin resistance stage during certain periods of maturation, have different glycolytic/metabolic responses during exercise, have a tendency for higher fat oxidation during exercise and show different heat dissipation mechanisms compared to adults. These features point out that young athletes may need different nutritional advice on carbohydrate for exercise to those from adult athletes. Sport drinks for example may need to be adapted to children specific needs. However, more research in this area is warranted to clarify sports nutrition needs of the young athlete to provide better and healthy nutritional guidance to young athletes

  16. Impact of dietary polyphenols on carbohydrate metabolism.

    Science.gov (United States)

    Hanhineva, Kati; Törrönen, Riitta; Bondia-Pons, Isabel; Pekkinen, Jenna; Kolehmainen, Marjukka; Mykkänen, Hannu; Poutanen, Kaisa

    2010-03-31

    Polyphenols, including flavonoids, phenolic acids, proanthocyanidins and resveratrol, are a large and heterogeneous group of phytochemicals in plant-based foods, such as tea, coffee, wine, cocoa, cereal grains, soy, fruits and berries. Growing evidence indicates that various dietary polyphenols may influence carbohydrate metabolism at many levels. In animal models and a limited number of human studies carried out so far, polyphenols and foods or beverages rich in polyphenols have attenuated postprandial glycemic responses and fasting hyperglycemia, and improved acute insulin secretion and insulin sensitivity. The possible mechanisms include inhibition of carbohydrate digestion and glucose absorption in the intestine, stimulation of insulin secretion from the pancreatic beta-cells, modulation of glucose release from the liver, activation of insulin receptors and glucose uptake in the insulin-sensitive tissues, and modulation of intracellular signalling pathways and gene expression. The positive effects of polyphenols on glucose homeostasis observed in a large number of in vitro and animal models are supported by epidemiological evidence on polyphenol-rich diets. To confirm the implications of polyphenol consumption for prevention of insulin resistance, metabolic syndrome and eventually type 2 diabetes, human trials with well-defined diets, controlled study designs and clinically relevant end-points together with holistic approaches e.g., systems biology profiling technologies are needed.

  17. Impact of Dietary Polyphenols on Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    Kati Hanhineva

    2010-03-01

    Full Text Available Polyphenols, including flavonoids, phenolic acids, proanthocyanidins and resveratrol, are a large and heterogeneous group of phytochemicals in plant-based foods, such as tea, coffee, wine, cocoa, cereal grains, soy, fruits and berries. Growing evidence indicates that various dietary polyphenols may influence carbohydrate metabolism at many levels. In animal models and a limited number of human studies carried out so far, polyphenols and foods or beverages rich in polyphenols have attenuated postprandial glycemic responses and fasting hyperglycemia, and improved acute insulin secretion and insulin sensitivity. The possible mechanisms include inhibition of carbohydrate digestion and glucose absorption in the intestine, stimulation of insulin secretion from the pancreatic b-cells, modulation of glucose release from the liver, activation of insulin receptors and glucose uptake in the insulin-sensitive tissues, and modulation of intracellular signalling pathways and gene expression. The positive effects of polyphenols on glucose homeostasis observed in a large number of in vitro and animal models are supported by epidemiological evidence on polyphenol-rich diets. To confirm the implications of polyphenol consumption for prevention of insulin resistance, metabolic syndrome and eventually type 2 diabetes, human trials with well-defined diets, controlled study designs and clinically relevant end-points together with holistic approaches e.g., systems biology profiling technologies are needed.

  18. Social influence: compliance and conformity.

    Science.gov (United States)

    Cialdini, Robert B; Goldstein, Noah J

    2004-01-01

    This review covers recent developments in the social influence literature, focusing primarily on compliance and conformity research published between 1997 and 2002. The principles and processes underlying a target's susceptibility to outside influences are considered in light of three goals fundamental to rewarding human functioning. Specifically, targets are motivated to form accurate perceptions of reality and react accordingly, to develop and preserve meaningful social relationships, and to maintain a favorable self-concept. Consistent with the current movement in compliance and conformity research, this review emphasizes the ways in which these goals interact with external forces to engender social influence processes that are subtle, indirect, and outside of awareness.

  19. Nonlocal gravity: Conformally flat spacetimes

    CERN Document Server

    Bini, Donato

    2016-01-01

    The field equations of the recent nonlocal generalization of Einstein's theory of gravitation are presented in a form that is reminiscent of general relativity. The implications of the nonlocal field equations are studied in the case of conformally flat spacetimes. Even in this simple case, the field equations are intractable. Therefore, to gain insight into the nature of these equations, we investigate the structure of nonlocal gravity in two-dimensional spacetimes. While any smooth 2D spacetime is conformally flat and satisfies Einstein's field equations, only a subset containing either a Killing vector or a homothetic Killing vector can satisfy the field equations of nonlocal gravity.

  20. Epigenetic dominance of prion conformers.

    Directory of Open Access Journals (Sweden)

    Eri Saijo

    2013-10-01

    Full Text Available Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP primary structures interact with distinct prion conformations to influence pathogenesis, we produced transgenic (Tg mice expressing different sheep scrapie susceptibility alleles, varying only at a single amino acid at PrP residue 136. Tg mice expressing ovine PrP with alanine (A at (OvPrP-A136 infected with SSBP/1 scrapie prions propagated a relatively stable (S prion conformation, which accumulated as punctate aggregates in the brain, and produced prolonged incubation times. In contrast, Tg mice expressing OvPrP with valine (V at 136 (OvPrP-V136 infected with the same prions developed disease rapidly, and the converted prion was comprised of an unstable (U, diffusely distributed conformer. Infected Tg mice co-expressing both alleles manifested properties consistent with the U conformer, suggesting a dominant effect resulting from exclusive conversion of OvPrP-V136 but not OvPrP-A136. Surprisingly, however, studies with monoclonal antibody (mAb PRC5, which discriminates OvPrP-A136 from OvPrP-V136, revealed substantial conversion of OvPrP-A136. Moreover, the resulting OvPrP-A136 prion acquired the characteristics of the U conformer. These results, substantiated by in vitro analyses, indicated that co-expression of OvPrP-V136 altered the conversion potential of OvPrP-A136 from the S to

  1. Acute Effects of Carbohydrate Supplementation on Intermittent Sports Performance

    Directory of Open Access Journals (Sweden)

    Lindsay B. Baker

    2015-07-01

    Full Text Available Intermittent sports (e.g., team sports are diverse in their rules and regulations but similar in the pattern of play; that is, intermittent high-intensity movements and the execution of sport-specific skills over a prolonged period of time (~1–2 h. Performance during intermittent sports is dependent upon a combination of anaerobic and aerobic energy systems, both of which rely on muscle glycogen and/or blood glucose as an important substrate for energy production. The aims of this paper are to review: (1 potential biological mechanisms by which carbohydrate may impact intermittent sport performance; (2 the acute effects of carbohydrate ingestion on intermittent sport performance, including intermittent high-intensity exercise capacity, sprinting, jumping, skill, change of direction speed, and cognition; and (3 what recommendations can be derived for carbohydrate intake before/during exercise in intermittent sports based on the available evidence. The most researched intermittent sport is soccer but some sport-specific studies have also been conducted in other sports (e.g., rugby, field hockey, basketball, American football, and racquet sports. Carbohydrate ingestion before/during exercise has been shown in most studies to enhance intermittent high-intensity exercise capacity. However, studies have shown mixed results with regards to the acute effects of carbohydrate intake on sprinting, jumping, skill, change of direction speed, and cognition. In most of these studies the amount of carbohydrate consumed was ~30–60 g/h in the form of a 6%–7% carbohydrate solution comprised of sucrose, glucose, and/or maltodextrin. The magnitude of the impact that carbohydrate ingestion has on intermittent sport performance is likely dependent on the carbohydrate status of the individual; that is, carbohydrate ingestion has the greatest impact on performance under circumstances eliciting fatigue and/or hypoglycemia. Accordingly, carbohydrate ingestion before

  2. Molecular mechanics conformational analysis of tylosin

    Science.gov (United States)

    Ivanov, Petko M.

    1998-01-01

    The conformations of the 16-membered macrolide antibiotic tylosin were studied with molecular mechanics (AMBER∗ force field) including modelling of the effect of the solvent on the conformational preferences (GB/SA). A Monte Carlo conformational search procedure was used for finding the most probable low-energy conformations. The present study provides complementary data to recently reported analysis of the conformations of tylosin based on NMR techniques. A search for the low-energy conformations of protynolide, a 16-membered lactone containing the same aglycone as tylosin, was also carried out, and the results were compared with the observed conformation in the crystal as well as with the most probable conformations of the macrocyclic ring of tylosin. The dependence of the results on force field was also studied by utilizing the MM3 force field. Some particular conformations were computed with the semiempirical molecular orbital methods AM1 and PM3.

  3. Correct Representation of Conformational Equilibria.

    Science.gov (United States)

    Fulop, F.; And Others

    1983-01-01

    In representing conformational equilibria of compounds having only one chiral center, erroneous formulas showing different antipodes on the two sides of the equilibrium are rare. In contrast, with compounds having two or more chiral centers especially with saturated heterocycles, this erroneous representation occurs frequently in the chemical…

  4. Temperature: Human Regulating, Ants Conforming

    Science.gov (United States)

    Clopton, Joe R.

    2007-01-01

    Biological processes speed up as temperature rises. Procedures for demonstrating this with ants traveling on trails, and data gathered by students on the Argentine ant ("Linepithema humile") are presented. The concepts of temperature regulation and conformity are detailed with a focus on the processes rather than on terms that label the organisms.

  5. A tutorial on conformal prediction

    CERN Document Server

    Shafer, Glenn

    2007-01-01

    Conformal prediction uses past experience to determine precise levels of confidence in new predictions. Given an error probability $\\epsilon$, together with a method that makes a prediction $\\hat{y}$ of a label $y$, it produces a set of labels, typically containing $\\hat{y}$, that also contains $y$ with probability $1-\\epsilon$. Conformal prediction can be applied to any method for producing $\\hat{y}$: a nearest-neighbor method, a support-vector machine, ridge regression, etc. Conformal prediction is designed for an on-line setting in which labels are predicted successively, each one being revealed before the next is predicted. The most novel and valuable feature of conformal prediction is that if the successive examples are sampled independently from the same distribution, then the successive predictions will be right $1-\\epsilon$ of the time, even though they are based on an accumulating dataset rather than on independent datasets. In addition to the model under which successive examples are sampled indepen...

  6. Anomalous Dimensions of Conformal Baryons

    DEFF Research Database (Denmark)

    Pica, Claudio; Sannino, Francesco

    2016-01-01

    We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within...

  7. Exceptional and Spinorial Conformal Windows

    DEFF Research Database (Denmark)

    Mojaza, Matin; Pica, Claudio; Ryttov, Thomas

    2012-01-01

    We study the conformal window of gauge theories containing fermionic matter fields, where the gauge group is any of the exceptional groups with the fermions transforming according to the fundamental and adjoint representations and the orthogonal groups where the fermions transform according...

  8. Conformal Relativity: Theory and Observations

    CERN Document Server

    Pervushin, V; Zorin, A

    2005-01-01

    Theoretical and observational arguments are listed in favor of a new principle of relativity of units of measurements as the basis of a conformal-invariant unification of General Relativity and Standard Model by replacement of all masses with a scalar (dilaton) field. The relative units mean conformal observables: the coordinate distance, conformal time, running masses, and constant temperature. They reveal to us a motion of a universe along its hypersurface in the field space of events like a motion of a relativistic particle in the Minkowski space, where the postulate of the vacuum as a state with minimal energy leads to arrow of the geometric time. In relative units, the unified theory describes the Cold Universe Scenario, where the role of the conformal dark energy is played by a free minimal coupling scalar field in agreement with the most recent distance-redshift data from type Ia supernovae. In this Scenario, the evolution of the Universe begins with the effect of intensive creation of primordial W-Z-b...

  9. Conformal mapping for multiple terminals

    Science.gov (United States)

    Wang, Weimin; Ma, Wenying; Wang, Qiang; Ren, Hao

    2016-11-01

    Conformal mapping is an important mathematical tool that can be used to solve various physical and engineering problems in many fields, including electrostatics, fluid mechanics, classical mechanics, and transformation optics. It is an accurate and convenient way to solve problems involving two terminals. However, when faced with problems involving three or more terminals, which are more common in practical applications, existing conformal mapping methods apply assumptions or approximations. A general exact method does not exist for a structure with an arbitrary number of terminals. This study presents a conformal mapping method for multiple terminals. Through an accurate analysis of boundary conditions, additional terminals or boundaries are folded into the inner part of a mapped region. The method is applied to several typical situations, and the calculation process is described for two examples of an electrostatic actuator with three electrodes and of a light beam splitter with three ports. Compared with previously reported results, the solutions for the two examples based on our method are more precise and general. The proposed method is helpful in promoting the application of conformal mapping in analysis of practical problems.

  10. Anomalous Dimensions of Conformal Baryons

    DEFF Research Database (Denmark)

    Pica, Claudio; Sannino, Francesco

    2016-01-01

    We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small, within the $...

  11. The use of carbohydrates during exercise as an ergogenic aid.

    Science.gov (United States)

    Cermak, Naomi M; van Loon, Luc J C

    2013-11-01

    Carbohydrate and fat are the two primary fuel sources oxidized by skeletal muscle tissue during prolonged (endurance-type) exercise. The relative contribution of these fuel sources largely depends on the exercise intensity and duration, with a greater contribution from carbohydrate as exercise intensity is increased. Consequently, endurance performance and endurance capacity are largely dictated by endogenous carbohydrate availability. As such, improving carbohydrate availability during prolonged exercise through carbohydrate ingestion has dominated the field of sports nutrition research. As a result, it has been well-established that carbohydrate ingestion during prolonged (>2 h) moderate-to-high intensity exercise can significantly improve endurance performance. Although the precise mechanism(s) responsible for the ergogenic effects are still unclear, they are likely related to the sparing of skeletal muscle glycogen, prevention of liver glycogen depletion and subsequent development of hypoglycemia, and/or allowing high rates of carbohydrate oxidation. Currently, for prolonged exercise lasting 2-3 h, athletes are advised to ingest carbohydrates at a rate of 60 g·h⁻¹ (~1.0-1.1 g·min⁻¹) to allow for maximal exogenous glucose oxidation rates. However, well-trained endurance athletes competing longer than 2.5 h can metabolize carbohydrate up to 90 g·h⁻¹ (~1.5-1.8 g·min⁻¹) provided that multiple transportable carbohydrates are ingested (e.g. 1.2 g·min⁻¹ glucose plus 0.6 g·min⁻¹ of fructose). Surprisingly, small amounts of carbohydrate ingestion during exercise may also enhance the performance of shorter (45-60 min), more intense (>75 % peak oxygen uptake; VO(₂peak)) exercise bouts, despite the fact that endogenous carbohydrate stores are unlikely to be limiting. The mechanism(s) responsible for such ergogenic properties of carbohydrate ingestion during short, more intense exercise bouts has been suggested to reside in the central nervous

  12. A perspective on the primary and three-dimensional structures of carbohydrates.

    Science.gov (United States)

    Widmalm, Göran

    2013-08-30

    Carbohydrates, in more biologically oriented areas referred to as glycans, constitute one of the four groups of biomolecules. The glycans, often present as glycoproteins or glycolipids, form highly complex structures. In mammals ten monosaccharides are utilized in building glycoconjugates in the form of oligo- (up to about a dozen monomers) and polysaccharides. Subsequent modifications and additions create a large number of different compounds. In bacteria, more than a hundred monosaccharides have been reported to be constituents of lipopolysaccharides, capsular polysaccharides, and exopolysaccharides. Thus, the number of polysaccharide structures possible to create is huge. NMR spectroscopy plays an essential part in elucidating the primary structure, that is, monosaccharide identity and ring size, anomeric configuration, linkage position, and sequence, of the sugar residues. The structural studies may also employ computational approaches for NMR chemical shift predictions (CASPER program). Once the components and sequence of sugar residues have been unraveled, the three-dimensional arrangement of the sugar residues relative to each other (conformation), their flexibility (transitions between and populations of conformational states), together with the dynamics (timescales) should be addressed. To shed light on these aspects we have utilized a combination of experimental liquid state NMR techniques together with molecular dynamics simulations. For the latter a molecular mechanics force field such as our CHARMM-based PARM22/SU01 has been used. The experimental NMR parameters acquired are typically (1)H,(1)H cross-relaxation rates (related to NOEs), (3)JCH and (3)JCCtrans-glycosidic coupling constants and (1)H,(13)C- and (1)H,(1)H-residual dipolar couplings. At a glycosidic linkage two torsion angles ϕ and ψ are defined and for 6-substituted residues also the ω torsion angle is required. Major conformers can be identified for which highly populated states are

  13. Frankincense tapping reduces the carbohydrate storage of Boswellia trees

    NARCIS (Netherlands)

    Mengistu, T.; Sterck, F.J.; Fetene, M.; Bongers, F.

    2013-01-01

    Carbohydrates fixed by photosynthesis are stored in plant organs in the form of starch or sugars. Starch and sugars sum to the total non-structural carbohydrate pool (TNC) and may serve as intermediate pools between assimilation and utilization. We examined the impact of tapping on TNC concentration

  14. Carbohydrate-responsive gene expression in adipose tissue of rats

    Science.gov (United States)

    Although obesity is often associated with high fat diets, it can develop from a variety of meal patterns. Excessive intake of simple carbohydrates is one consistent eating behavior leading to obesity. However, the impact of over-consumption of diets with high carbohydrate-to-fat ratios (C/F) on body...

  15. The effect of carbohydrates on alpha-amylase activity measurements

    NARCIS (Netherlands)

    Baks, T.; Janssen, A.E.M.; Boom, R.M.

    2006-01-01

    The Ceralpha method can be used for ¿-amylase activity measurements during the hydrolysis of starch at high substrate concentrations (>40 wt.%). However, the results are affected by the carbohydrates present in the samples. The effect of carbohydrates on the Ceralpha ¿-amylase activity measuremen

  16. Genetic Analyses of Soluble Carbohydrate Concentrations in Onion Bulbs

    Science.gov (United States)

    Fructans are the primary soluble carbohydrate in onion (Allium cepa L.) bulbs and show significant correlations with dry weights and pungency. In this research, we estimated the genetic effects and interactions between two chromosome regions associated with higher amounts of soluble carbohydrates i...

  17. Chemical Changes in Carbohydrates Produced by Thermal Processing.

    Science.gov (United States)

    Hoseney, R. Carl

    1984-01-01

    Discusses chemical changes that occur in the carbohydrates found in food products when these products are subjected to thermal processing. Topics considered include browning reactions, starch found in food systems, hydrolysis of carbohydrates, extrusion cooking, processing of cookies and candies, and alterations in gums. (JN)

  18. Using structure to inform carbohydrate binding module function

    NARCIS (Netherlands)

    Abbott, D. Wade; Lammerts van Bueren, Alicia

    2014-01-01

    Generally, non-catalytic carbohydrate binding module (CBM) specificity has been shown to parallel the catalytic activity of the carbohydrate active enzyme (CAZyme) module it is appended to. With the rapid expansion in metagenomic sequence space for the potential discovery of new CBMs in addition to

  19. Dynamic fluctuations of protein-carbohydrate interactions promote protein aggregation.

    Directory of Open Access Journals (Sweden)

    Vladimir Voynov

    Full Text Available Protein-carbohydrate interactions are important for glycoprotein structure and function. Antibodies of the IgG class, with increasing significance as therapeutics, are glycosylated at a conserved site in the constant Fc region. We hypothesized that disruption of protein-carbohydrate interactions in the glycosylated domain of antibodies leads to the exposure of aggregation-prone motifs. Aggregation is one of the main problems in protein-based therapeutics because of immunogenicity concerns and decreased efficacy. To explore the significance of intramolecular interactions between aromatic amino acids and carbohydrates in the IgG glycosylated domain, we utilized computer simulations, fluorescence analysis, and site-directed mutagenesis. We find that the surface exposure of one aromatic amino acid increases due to dynamic fluctuations. Moreover, protein-carbohydrate interactions decrease upon stress, while protein-protein and carbohydrate-carbohydrate interactions increase. Substitution of the carbohydrate-interacting aromatic amino acids with non-aromatic residues leads to a significantly lower stability than wild type, and to compromised binding to Fc receptors. Our results support a mechanism for antibody aggregation via decreased protein-carbohydrate interactions, leading to the exposure of aggregation-prone regions, and to aggregation.

  20. Why use DFT methods in the study of carbohydrates?

    Science.gov (United States)

    The recent advances in density functional theory (DFT) and computer technology allow us to study systems with more than 100 atoms routinely. This makes it feasible to study large carbohydrate molecules via quantum mechanical methods, whereas in the past, studies of carbohydrates were restricted to ...

  1. Influence of dietary carbohydrate level on endocrine status and hepatic carbohydrate metabolism in the marine fish Sparus sarba.

    Science.gov (United States)

    Leung, L Y; Woo, Norman Y S

    2012-04-01

    Silver sea bream, Sparus sarba, were fed two diets of different carbohydrate levels (2 and 20% dextrin) for 4 weeks, and the effects on organ indices, liver composition, serum metabolite and hormone levels and gene expression profile of key enzymes of carbohydrate metabolism in the liver were investigated. By using real-time PCR, mRNA expression levels of carbohydrate metabolic enzymes including glucokinase (GK, glycolysis), glucose-6-phosphatase (G6Pase, gluconeogenesis), glycogen synthase (GS, glycogenesis), glycogen phosphorylase (GP, glycogenolysis) and glucose-6-phosphate dehydrogenase (G6PDH, pentose phosphate pathway) in liver of sea bream have been examined, and it was found that high dietary carbohydrate level increased mRNA level of GK but decreased mRNA levels of G6Pase and GP. However, mRNA levels of GS and G6PDH were not significantly influenced by dietary carbohydrate. Silver sea bream fed high dietary carbohydrate had higher hepatosomatic index (HSI), liver glycogen and protein, but there were no significant changes in gonadosomatic index (GSI), serum glucose and protein level, as well as liver lipid and moisture level. Pituitary growth hormone (GH) and hepatic insulin-like growth factor I (IGF-I) transcript abundance were assayed by real-time PCR, and it was found that both parameters remained unchanged in fish fed different dietary carbohydrate levels. Serum triiodothyronine (T(3)) and thyroxine (T(4)) were not significantly affected by dietary carbohydrate levels, but lower serum cortisol level was found in fish fed high dietary carbohydrate level. These results suggest that silver sea bream is able to adapt to a diet with high carbohydrate content (up to 20% dextrin), the consumption of which would lead to fundamental re-organization of carbohydrate metabolism resulting in hepatic glycogen deposition.

  2. A Simple and Clean Method for O-Isopropylidenation of Carbohydrates

    Energy Technology Data Exchange (ETDEWEB)

    Rong, Yuan Wei; Zhang, Qi Hua; Wang, Wei; Li, Bao Lin [Shaanxi Normal Univ., Xi' an (China)

    2014-07-15

    An efficient catalysis system for the synthesis of O-isopropylidene derivatives of sugars and polyhydroxy alcohols has been developed with sulfonated polystyrene cation exchange resin CAT600 as a catalyst. The key advantages of this protocol are simple workup, good yields and the recoverability, the innocuity and low cost of the catalyst. As a green, general and efficient reaction system, this method is expected to attract much attention for the preparation of various O-isopropylidene sugar derivatives in a large scale. Protection of hydroxyl functions by O-isopropylidenation is an important method in the field of carbohydrate chemistry. Due to its convenient application in synthetic, configurational and conformational studies, the O-isopropylidene derivatives of sugars play an important role in the research of building blocks, such as glycosyl acceptors and glycosyl donors. Additionally, these derivatives of sugars are important in the synthesis of various natural products.

  3. Structures of parasite calreticulins provide insights into their flexibility and dual carbohydrate/peptide-binding properties

    Science.gov (United States)

    Moreau, Christophe; Cioci, Gianluca; Iannello, Marina; Laffly, Emmanuelle; Chouquet, Anne; Ferreira, Arturo; Thielens, Nicole M.; Gaboriaud, Christine

    2016-01-01

    Calreticulin (CRT) is a multifaceted protein, initially discovered as an endoplasmic reticulum (ER) chaperone protein, that is essential in calcium metabolism. Various implications in cancer, early development and immunology have been discovered more recently for CRT, as well as its role as a dominant ‘eat-me’ prophagocytic signal. Intriguingly, cell-surface exposure/secretion of CRT is among the infective strategies used by parasites such as Trypanosoma cruzi, Entamoeba histolytica, Taenia solium, Leishmania donovani and Schistosoma mansoni. Because of the inherent flexibility of CRTs, their analysis by X-ray crystallography requires the design of recombinant constructs suitable for crystallization, and thus only the structures of two very similar mammalian CRT lectin domains are known. With the X-ray structures of two distant parasite CRTs, insights into species structural determinants that might be harnessed to fight against the parasites without affecting the functions of the host CRT are now provided. Moreover, although the hypothesis that CRT can exhibit both open and closed conformations has been proposed in relation to its chaperone function, only the open conformation has so far been observed in crystal structures. The first evidence is now provided of a complex conformational transition with the junction reoriented towards P-domain closure. SAXS experiments also provided additional information about the flexibility of T. cruzi CRT in solution, thus complementing crystallographic data on the open conformation. Finally, regarding the conserved lectin-domain structure and chaperone function, evidence is provided of its dual carbohydrate/protein specificity and a new scheme is proposed to interpret such unusual substrate-binding properties. These fascinating features are fully consistent with previous experimental observations, as discussed considering the broad spectrum of CRT sequence conservations and differences. PMID:27840680

  4. Fake Conformal Symmetry in Unimodular Gravity

    CERN Document Server

    Oda, Ichiro

    2016-01-01

    We study Weyl symmetry (local conformal symmetry) in unimodular gravity. It is shown that the Noether currents for both Weyl symmetry and global scale symmetry, identically vanish as in the conformally invariant scalar-tensor gravity. We clearly explain why in the class of conformally invariant gravitational theories, the Noether currents vanish by starting with the conformally invariant scalar-tensor gravity. Moreover, we comment on both classical and quantum-mechanical equivalences among Einstein's general relativity, the conformally invariant scalar-tensor gravity and the Weyl-transverse (WTDiff) gravity. Finally, we discuss the Weyl current in the conformally invariant scalar action and see that it is also vanishing.

  5. Fake conformal symmetry in unimodular gravity

    Science.gov (United States)

    Oda, Ichiro

    2016-08-01

    We study Weyl symmetry (local conformal symmetry) in unimodular gravity. It is shown that the Noether currents for both Weyl symmetry and global scale symmetry vanish exactly as in conformally invariant scalar-tensor gravity. We clearly explain why in the class of conformally invariant gravitational theories, the Noether currents vanish by starting with conformally invariant scalar-tensor gravity. Moreover, we comment on both classical and quantum-mechanical equivalences in Einstein's general relativity, conformally invariant scalar-tensor gravity, and the Weyl-transverse gravity. Finally, we discuss the Weyl current in the conformally invariant scalar action and see that it is also vanishing.

  6. [Carbohydrate absorption and malabsorption (author's transl)].

    Science.gov (United States)

    Caspary, W F

    1977-06-01

    Starch is digested intraluminally by alpha-amylase to maltose, maltotriose, and alpha-limit dextrins. These products, as well as the disaccharides sucrose and lactose, undergo enzymatic hydrolysis to monosaccharides at the brush border surface. The monosaccharides enter the absorbing cell by specific transport mechanisms ("carriers"). Primary carbohydrate (CH) intolerance is characterized by the congenital or acquired absence of individual brush border enzymes or of monosaccharide "carriers" without morphologic abnormalities of the intestinal villus: lactose, sucrose and trehalose intolerance and glucose-galactose malabsorption (brush border diseases). Secondary CH intolerance arises when surface digestion and absorption are reduced due to structural changes of the intestinal mucosa: e.g., decrease or absence of villi with sprue and reduction of the absorbing surface with intestinal resection. Watery diarrhea is the lead symptom. Many drugs delay or interfere with CH absorption. This action may be viewed either as an unwanted side effect or as a welcome therapeutic principle.

  7. Arabinogalactan proteins: focus on carbohydrate active enzymes

    Directory of Open Access Journals (Sweden)

    Eva eKnoch

    2014-06-01

    Full Text Available Arabinogalactan proteins (AGPs are a highly diverse class of cell surface proteoglycans that are commonly found in most plant species. AGPs play important roles in many cellular processes during plant development, such as reproduction, cell proliferation, pattern formation and growth, and in plant-microbe interaction. However, little is known about the molecular mechanisms of their function. Numerous studies using monoclonal antibodies that recognize different AGP glycan epitopes have shown the appearance of a slightly altered AGP glycan in a specific stage of development in plant cells. Therefore, it is anticipated that the biosynthesis and degradation of AGP glycan is tightly regulated during development. Until recently, however, little was known about the enzymes involved in the metabolism of AGP glycans. In this review, we summarize recent discoveries of carbohydrate active enzymes (CAZy; http://www.cazy.org/ involved in the biosynthesis and degradation of AGP glycans, and we discuss the biological role of these enzymes in plant development.

  8. Carbohydrate based materials for gamma radiation shielding

    Science.gov (United States)

    Tabbakh, F.; Babaee, V.; Naghsh-Nezhad, Z.

    2015-05-01

    Due to the limitation in using lead as a shielding material for its toxic properties and limitation in abundance, price or non-flexibility of other commonly used materials, finding new shielding materials and compounds is strongly required. In this conceptual study carbohydrate based compounds were considered as new shielding materials. The simulation of radiation attenuation is performed using MCNP and Geant4 with a good agreement in the results. It is found that, the thickness of 2 mm of the proposed compound may reduce up to 5% and 50% of 1 MeV and 35 keV gamma-rays respectively in comparison with 15% and 100% for the same thickness of lead.

  9. Glycosidases: a key to tailored carbohydrates.

    Science.gov (United States)

    Bojarová, Pavla; Kren, Vladimír

    2009-04-01

    In recent years, carbohydrate-processing enzymes have become the enzymes of choice in many applications thanks to their stereoselectivity and efficiency. This review presents recent developments in glycosidase-catalyzed synthesis via two complementary approaches: the use of wild-type enzymes with engineered substrates, and mutant glycosidases. Genetic engineering has recently produced glucuronyl synthases, an inverting xylosynthase and the first mutant endo-beta-N-acetylglucosaminidase. A thorough selection of enzyme strains and aptly modified substrates have resulted in rare glycostructures, such as N-acetyl-beta-galactosaminuronates, beta1,4-linked mannosides and alpha1,4-linked galactosides. The efficient selection of mutant enzymes is facilitated by high-throughput screening assays involving the co-expression of coupled enzymes or chemical complementation. Selective glycosidase inhibitors and highly specific glycosidases are finding attractive applications in biomedicine, biology and proteomics.

  10. Carbohydrate deficient transferrin (CDT) in alcoholic cirrhosis: a kinetic study

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Grønbaek, M; Møller, Søren

    1997-01-01

    concentration than controls with a low alcohol intake (detected between carbohydrate deficient transferrin in artery and liver vein or artery and renal vein, either in patients with alcoholic cirrhosis (n = 11) or in controls (n = 8......BACKGROUND/AIMS: Carbohydrate deficient transferrin has been introduced as a marker of excessive alcohol intake. The present study was undertaken in order to measure the circulating level of carbohydrate deficient transferrin in patients with alcoholic cirrhosis and to assess arteriovenous kinetics...... of carbohydrate deficient transferrin in liver and kidney. METHODS/RESULTS: The median value of serum carbohydrate deficient transferrin was 16.0 U/l in patients with alcoholic cirrhosis (n = 41), and this value was not significantly different from that of a normal control group (median 17.4 U/l, n = 55, ns...

  11. Carbohydrate CuAAC click chemistry for therapy and diagnosis.

    Science.gov (United States)

    He, Xiao-Peng; Zeng, Ya-Li; Zang, Yi; Li, Jia; Field, Robert A; Chen, Guo-Rong

    2016-06-24

    Carbohydrates are important as signaling molecules and for cellular recognition events, therefore offering scope for the development of carbohydrate-mimetic diagnostics and drug candidates. As a consequence, the construction of carbohydrate-based bioactive compounds and sensors has become an active research area. While the advent of click chemistry has greatly accelerated the progress of medicinal chemistry and chemical biology, recent literature has seen an extensive use of such approaches to construct functionally diverse carbohydrate derivatives. Here we summarize some of the progress, covering the period 2010 to mid-2015, in Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition CuAAC "click chemistry" of carbohydrate derivatives, in the context of potential therapeutic and diagnostic tool development.

  12. Defined presentation of carbohydrates on a duplex DNA scaffold.

    Science.gov (United States)

    Schlegel, Mark K; Hütter, Julia; Eriksson, Magdalena; Lepenies, Bernd; Seeberger, Peter H

    2011-12-16

    A new method for the spatially defined alignment of carbohydrates on a duplex DNA scaffold is presented. The use of an N-hydroxysuccinimide (NHS)-ester phosphoramidite along with carbohydrates containing an alkylamine linker allows for on-column labeling during solid-phase oligonucleotide synthesis. This modification method during solid-phase synthesis only requires the use of minimal amounts of complex carbohydrates. The covalently attached carbohydrates are presented in the major groove of the B-form duplex DNA as potential substrates for murine type II C-type lectin receptors mMGL1 and mMGL2. CD spectroscopy and thermal melting revealed only minimal disturbance of the overall helical structure. Surface plasmon resonance and cellular uptake studies with bone-marrow-derived dendritic cells were used to assess the capability of these carbohydrate-modified duplexes to bind to mMGL receptors.

  13. Methods for Shortening and Extending the Carbon Chain in Carbohydrates

    DEFF Research Database (Denmark)

    Monrad, Rune Nygaard

    2008-01-01

    Carbohydrates play a central role in a variety of physiological and pathological processes such as HIV, cancer and diabetes. The understanding of these processes and the development of specific therapeutic agents is relying on the ability to chemically synthesize unnatural sugars, glycoconjugates...... and carbohydrate mimetics. Such polyhydroxylated compounds are conveniently synthesized from carbohydrates, however, due to the scarcity of many sugars from nature, efficient methods for transformation of readily available carbohydrates into valuable chiral building blocks are required. The work presented...... in this thesis focuses on the development and application of transition metal mediated methods for shortening and extending the carbon chain in carbohydrates thereby providing access to lower and higher sugars.A new catalytic procedure for shortening unprotected sugars by one carbon atom has been developed...

  14. Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes

    DEFF Research Database (Denmark)

    Cockburn, Darrell; Wilkens, Casper; Dilokpimol, Adiphol

    2016-01-01

    Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical...... for the activity of their cognate enzyme, though they are not readily detected in the sequence of a protein, but normally require a crystal structure of a complex for their identification. A variety of methods, including affinity electrophoresis (AE), insoluble polysaccharide pulldown (IPP) and surface plasmon...... sites, but also for identifying new ones, even without structural data available. We further verify the chosen assays discriminate between known SBS/CBM containing enzymes and negative controls. Altogether 35 enzymes are screened for the presence of SBSs or CBMs and several novel binding sites...

  15. Dietary non-digestible carbohydrates and the resistance to intestinal infections

    NARCIS (Netherlands)

    Bruggencate, ten S.J.M.

    2004-01-01

    Keywords: Non-digestible carbohydrates, prebiotics, inulin, FOS, calcium, microflora, short-chain fatty acids, mucin, intestinal permeability, salmonella, infection, rat, humanDietary non-digestible carbohydrates and the resistance to intestinal infectionsNon-digestible carbohydrates (NDC) stimulate

  16. Carbohydrate-enriched cyanobacterial biomass as feedstock for bio-methane production through anaerobic digestion

    DEFF Research Database (Denmark)

    Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

    2013-01-01

    The anaerobic digestion performance using carbohydrate-enriched biomass of Arthrospira platensis was studied. The carbohydrate enrichment was achieved after the cultivation of A. platensis under phosphorus limitation conditions. Three biomass compositions (60%, 40% and 20% carbohydrates content) ...

  17. The case for low carbohydrate diets in diabetes management

    Directory of Open Access Journals (Sweden)

    McFarlane Samy I

    2005-07-01

    Full Text Available Abstract A low fat, high carbohydrate diet in combination with regular exercise is the traditional recommendation for treating diabetes. Compliance with these lifestyle modifications is less than satisfactory, however, and a high carbohydrate diet raises postprandial plasma glucose and insulin secretion, thereby increasing risk of CVD, hypertension, dyslipidemia, obesity and diabetes. Moreover, the current epidemic of diabetes and obesity has been, over the past three decades, accompanied by a significant decrease in fat consumption and an increase in carbohydrate consumption. This apparent failure of the traditional diet, from a public health point of view, indicates that alternative dietary approaches are needed. Because carbohydrate is the major secretagogue of insulin, some form of carbohydrate restriction is a prima facie candidate for dietary control of diabetes. Evidence from various randomized controlled trials in recent years has convinced us that such diets are safe and effective, at least in short-term. These data show low carbohydrate diets to be comparable or better than traditional low fat high carbohydrate diets for weight reduction, improvement in the dyslipidemia of diabetes and metabolic syndrome as well as control of blood pressure, postprandial glycemia and insulin secretion. Furthermore, the ability of low carbohydrate diets to reduce triglycerides and to increase HDL is of particular importance. Resistance to such strategies has been due, in part, to equating it with the popular Atkins diet. However, there are many variations and room for individual physician planning. Some form of low carbohydrate diet, in combination with exercise, is a viable option for patients with diabetes. However, the extreme reduction of carbohydrate of popular diets (

  18. Blood Triglycerides Levels and Dietary Carbohydrate Indices in Healthy Koreans

    Science.gov (United States)

    Kang, Ji Yeon

    2016-01-01

    Objectives: Previous studies have obtained conflicting findings regarding possible associations between indices measuring carbohydrate intake and dyslipidemia, which is an established risk factor of coronary heart disease. In the present study, we examined cross-sectional associations between carbohydrate indices, including the dietary glycemic index (GI), glycemic load (GL), total amount of carbohydrates, and the percentage of energy from carbohydrates, and a range of blood lipid parameters. Methods: This study included 1530 participants (554 men and 976 women) from 246 families within the Healthy Twin Study. We analyzed the associations using a generalized linear mixed model to control for familial relationships. Results: Levels of the Apo B were inversely associated with dietary GI, GL, and the amount of carbohydrate intake for men, but these relationships were not significant when fat-adjusted values of the carbohydrate indices were used. Triglyceride levels were positively associated with dietary GI and GL in women, and this pattern was more notable in overweight participants (body mass index [BMI] ≥25 kg/m2). However, total, low-density lipoprotein and high-density lipoprotein cholesterol levels were not significantly related with carbohydrate intake overall. Conclusions: Of the blood lipid parameters we investigated, only triglyceride levels were positively related with dietary carbohydrate indices among women participants in the Healthy Twin Study, with an interactive role observed for BMI. However, these associations were not observed in men, suggesting that the association between blood lipid levels and carbohydrate intake depends on the type of lipid, specific carbohydrate indices, gender, and BMI. PMID:27255074

  19. Conformal Gravity rotation curves with a conformal Higgs halo

    Science.gov (United States)

    Horne, Keith

    2016-06-01

    We discuss the effect of a conformally coupled Higgs field on conformal gravity (CG) predictions for the rotation curves of galaxies. The Mannheim-Kazanas (MK) metric is a valid vacuum solution of CG's fourth-order Poisson equation if and only if the Higgs field has a particular radial profile, S(r) = S0 a/(r + a), decreasing from S0 at r = 0 with radial scalelength a. Since particle rest masses scale with S(r)/S0, their world lines do not follow time-like geodesics of the MK metric gμν, as previously assumed, but rather those of the Higgs-frame MK metric tilde{g}_{μ ν }=Ω ^2 g_{μ ν }, with the conformal factor Ω(r) = S(r)/S0. We show that the required stretching of the MK metric exactly cancels the linear potential that has been invoked to fit galaxy rotation curves without dark matter. We also formulate, for spherical structures with a Higgs halo S(r), the CG equations that must be solved for viable astrophysical tests of CG using galaxy and cluster dynamics and lensing.

  20. Comparative analysis of carbohydrate active enzymes in Clostridium termitidis CT1112 reveals complex carbohydrate degradation ability.

    Directory of Open Access Journals (Sweden)

    Riffat I Munir

    Full Text Available Clostridium termitidis strain CT1112 is an anaerobic, gram positive, mesophilic, cellulolytic bacillus isolated from the gut of the wood-feeding termite, Nasutitermes lujae. It produces biofuels such as hydrogen and ethanol from cellulose, cellobiose, xylan, xylose, glucose, and other sugars, and therefore could be used for biofuel production from biomass through consolidated bioprocessing. The first step in the production of biofuel from biomass by microorganisms is the hydrolysis of complex carbohydrates present in biomass. This is achieved through the presence of a repertoire of secreted or complexed carbohydrate active enzymes (CAZymes, sometimes organized in an extracellular organelle called cellulosome. To assess the ability and understand the mechanism of polysaccharide hydrolysis in C. termitidis, the recently sequenced strain CT1112 of C. termitidis was analyzed for both CAZymes and cellulosomal components, and compared to other cellulolytic bacteria. A total of 355 CAZyme sequences were identified in C. termitidis, significantly higher than other Clostridial species. Of these, high numbers of glycoside hydrolases (199 and carbohydrate binding modules (95 were identified. The presence of a variety of CAZymes involved with polysaccharide utilization/degradation ability suggests hydrolysis potential for a wide range of polysaccharides. In addition, dockerin-bearing enzymes, cohesion domains and a cellulosomal gene cluster were identified, indicating the presence of potential cellulosome assembly.

  1. Comparative analysis of carbohydrate active enzymes in Clostridium termitidis CT1112 reveals complex carbohydrate degradation ability.

    Science.gov (United States)

    Munir, Riffat I; Schellenberg, John; Henrissat, Bernard; Verbeke, Tobin J; Sparling, Richard; Levin, David B

    2014-01-01

    Clostridium termitidis strain CT1112 is an anaerobic, gram positive, mesophilic, cellulolytic bacillus isolated from the gut of the wood-feeding termite, Nasutitermes lujae. It produces biofuels such as hydrogen and ethanol from cellulose, cellobiose, xylan, xylose, glucose, and other sugars, and therefore could be used for biofuel production from biomass through consolidated bioprocessing. The first step in the production of biofuel from biomass by microorganisms is the hydrolysis of complex carbohydrates present in biomass. This is achieved through the presence of a repertoire of secreted or complexed carbohydrate active enzymes (CAZymes), sometimes organized in an extracellular organelle called cellulosome. To assess the ability and understand the mechanism of polysaccharide hydrolysis in C. termitidis, the recently sequenced strain CT1112 of C. termitidis was analyzed for both CAZymes and cellulosomal components, and compared to other cellulolytic bacteria. A total of 355 CAZyme sequences were identified in C. termitidis, significantly higher than other Clostridial species. Of these, high numbers of glycoside hydrolases (199) and carbohydrate binding modules (95) were identified. The presence of a variety of CAZymes involved with polysaccharide utilization/degradation ability suggests hydrolysis potential for a wide range of polysaccharides. In addition, dockerin-bearing enzymes, cohesion domains and a cellulosomal gene cluster were identified, indicating the presence of potential cellulosome assembly.

  2. [Performance enhancement by carbohydrate intake during sport: effects of carbohydrates during and after high-intensity exercise].

    Science.gov (United States)

    Beelen, Milou; Cermak, Naomi M; van Loon, Luc J C

    2015-01-01

    Endogenous carbohydrate availability does not provide sufficient energy for prolonged moderate to high-intensity exercise. Carbohydrate ingestion during high-intensity exercise can therefore enhance performance.- For exercise lasting 1 to 2.5 hours, athletes are advised to ingest 30-60 g of carbohydrates per hour.- Well-trained endurance athletes competing for longer than 2.5 hours at high intensity can metabolise up to 90 g of carbohydrates per hour, provided that a mixture of glucose and fructose is ingested.- Athletes participating in intermittent or team sports are advised to follow the same strategies but the timing of carbohydrate intake depends on the type of sport.- If top performance is required again within 24 hours after strenuous exercise, the advice is to supplement endogenous carbohydrate supplies quickly within the first few hours post-exercise by ingesting large amounts of carbohydrate (1.2 g/kg/h) or a lower amount of carbohydrate (0.8 g/kg/h) with a small amount of protein (0.2-0.4 g/kg/h).

  3. Carbohydrate Content in the GDM Diet: Two Views: View 1: Nutrition Therapy in Gestational Diabetes: The Case for Complex Carbohydrates.

    Science.gov (United States)

    Hernandez, Teri L

    2016-05-01

    IN BRIEF Restriction of dietary carbohydrate has been the cornerstone for treatment of gestational diabetes mellitus (GDM). However, there is evidence that a balanced liberalization of complex carbohydrate as part of an overall eating plan in GDM meets treatment goals and may mitigate maternal adipose tissue insulin resistance, both of which may promote optimal metabolic outcomes for mother and offspring.

  4. Conformal Window and Correlation Functions in Lattice Conformal QCD

    Science.gov (United States)

    Iwasaki, Y.

    We discuss various aspects of Conformal Field Theories on the Lattice. We mainly investigate the SU(3) gauge theory with Nf degenerate fermions in the fundamental representation, employing the one-plaquette gauge action and the Wilson fermion action. First we make a brief review of our previous works on the phase structure of lattice gauge theories in terms of the gauge coupling constant and the quark mass. We thereby clarify the reason why we conjecture that the conformal window is 7 ≤ Nf ≤ 16. Secondly, we introduce a new concept, "conformal theories with IR cutof" and point out that any numerical simulation on a lattice is bounded by an IR cutoff ∧IR. Then we make predictions that when Nf is within the conformal window, the propagator of a meson G(t) behaves at large t, as G(t) = c exp (-mHt)/tα, that is, a modified Yukawa-type decay form, instead of the usual exponential decay form exp (-mHt), in the small quark mass region. This holds on an any lattice for any coupling constant g, as far as g is between 0 and g*, where g* is the IR fixed point. We verify that numerical results really satisfy the predictions for the Nf = 7 case and the Nf = 16 case. Thirdly, we discuss small number of flavors (Nf = 2 ˜ 6) QCD at finite temperatures. We point out theoretically and verify numerically that the correlation functions at T/Tc > 1 exhibit the characteristics of the conformal function with IR cutoff, an exponential decay with power correction. Investigating our numerical data by a new method which we call the "local-analysis" of propagators, we observe that the Nf = 7 case and the Nf = 2 at T ˜ 2Tc case are similar to each other, while the Nf = 16 case and the Nf = 2 at T = 102 ˜ 105Tc cases are similar to each other. Further, we observe our data are consistent with the picture that the Nf = 7 case and the Nf = 2 at T ˜ 2Tc case are close to the meson unparticle model. On the other hand, the Nf = 16 case and the Nf = 2 at T = 102 ˜ 105Tc cases are close to

  5. Conformal methods in general relativity

    CERN Document Server

    Valiente Kroon, Juan A

    2016-01-01

    This book offers a systematic exposition of conformal methods and how they can be used to study the global properties of solutions to the equations of Einstein's theory of gravity. It shows that combining these ideas with differential geometry can elucidate the existence and stability of the basic solutions of the theory. Introducing the differential geometric, spinorial and PDE background required to gain a deep understanding of conformal methods, this text provides an accessible account of key results in mathematical relativity over the last thirty years, including the stability of de Sitter and Minkowski spacetimes. For graduate students and researchers, this self-contained account includes useful visual models to help the reader grasp abstract concepts and a list of further reading, making this the perfect reference companion on the topic.

  6. Conformal gravity and "gravitational bubbles"

    CERN Document Server

    Berezin, V A; Eroshenko, Yu N

    2015-01-01

    We describe the general structure of the spherically symmetric solutions in the Weyl conformal gravity. The corresponding Bach equations are derived for the special type of metrics, which can be considered as the representative of the general class. The complete set of the pure vacuum solutions, consisting of two classes, is found. The first one contains the solutions with constant two-dimensional curvature scalar, and the representatives are the famous Robertson--Walker metrics. We called one of them the "gravitational bubbles", which is compact and with zero Weyl tensor. These "gravitational bubbles" are the pure vacuum curved space-times (without any material sources, including the cosmological constant), which are absolutely impossible in General Relativity. This phenomenon makes it easier to create the universe from "nothing". The second class consists of the solutions with varying curvature scalar. We found its representative as the one-parameter family, which can be conformally covered by the thee-para...

  7. Boundary terms of conformal anomaly

    Directory of Open Access Journals (Sweden)

    Sergey N. Solodukhin

    2016-01-01

    Full Text Available We analyze the structure of the boundary terms in the conformal anomaly integrated over a manifold with boundaries. We suggest that the anomalies of type B, polynomial in the Weyl tensor, are accompanied with the respective boundary terms of the Gibbons–Hawking type. Their form is dictated by the requirement that they produce a variation which compensates the normal derivatives of the metric variation on the boundary in order to have a well-defined variational procedure. This suggestion agrees with recent findings in four dimensions for free fields of various spins. We generalize this consideration to six dimensions and derive explicitly the respective boundary terms. We point out that the integrated conformal anomaly in odd dimensions is non-vanishing due to the boundary terms. These terms are specified in three and five dimensions.

  8. Boundary terms of conformal anomaly

    Energy Technology Data Exchange (ETDEWEB)

    Solodukhin, Sergey N., E-mail: Sergey.Solodukhin@lmpt.univ-tours.fr

    2016-01-10

    We analyze the structure of the boundary terms in the conformal anomaly integrated over a manifold with boundaries. We suggest that the anomalies of type B, polynomial in the Weyl tensor, are accompanied with the respective boundary terms of the Gibbons–Hawking type. Their form is dictated by the requirement that they produce a variation which compensates the normal derivatives of the metric variation on the boundary in order to have a well-defined variational procedure. This suggestion agrees with recent findings in four dimensions for free fields of various spins. We generalize this consideration to six dimensions and derive explicitly the respective boundary terms. We point out that the integrated conformal anomaly in odd dimensions is non-vanishing due to the boundary terms. These terms are specified in three and five dimensions.

  9. The Conformational Behaviour of Glucosamine

    Science.gov (United States)

    Peña, Isabel; Kolesniková, Lucie; Cabezas, Carlos; Bermúdez, Celina; Berdakin, Matías; Simao, Alcides; Alonso, José L.

    2014-06-01

    A laser ablation method has been successfully used to vaporize the bioactive amino monosaccharide D-glucosamine. Three cyclic α-4C1 pyranose forms have been identified using a combination of CP-FTMW and LA-MB-FTMW spectroscopy. Stereoelectronic hyperconjugative factors, like those associated with anomeric or gauche effects, as well as the cooperative OH\\cdotsO, OH\\cdotsN and NH\\cdotsO chains, extended along the entire molecule, are the main factors driving the conformational behavior. All observed conformers exhibit a counter-clockwise arrangement (cc) of the network of intramolecular hydrogen bonds. The results are compared with those recently obtained for D-glucose. J. L. Alonso, M. A. Lozoya, I. Peña, J. C. López, C. Cabezas, S. Mata, S. Blanco, Chem. Sci. 2014, 5, 515.

  10. Conformal Bootstrap in Mellin Space

    CERN Document Server

    Gopakumar, Rajesh; Sen, Kallol; Sinha, Aninda

    2016-01-01

    We propose a new approach towards analytically solving for the dynamical content of Conformal Field Theories (CFTs) using the bootstrap philosophy. This combines the original bootstrap idea of Polyakov with the modern technology of the Mellin representation of CFT amplitudes. We employ exchange Witten diagrams with built in crossing symmetry as our basic building blocks rather than the conventional conformal blocks in a particular channel. Demanding consistency with the operator product expansion (OPE) implies an infinite set of constraints on operator dimensions and OPE coefficients. We illustrate the power of this method in the epsilon expansion of the Wilson-Fisher fixed point by computing operator dimensions and, strikingly, OPE coefficients to higher orders in epsilon than currently available using other analytic techniques (including Feynman diagram calculations). Our results enable us to get a somewhat better agreement of certain observables in the 3d Ising model, with the precise numerical values that...

  11. Monogenic Functions in Conformal Geometry

    Directory of Open Access Journals (Sweden)

    Michael Eastwood

    2007-08-01

    Full Text Available Monogenic functions are basic to Clifford analysis. On Euclidean space they are defined as smooth functions with values in the corresponding Clifford algebra satisfying a certain system of first order differential equations, usually referred to as the Dirac equation. There are two equally natural extensions of these equations to a Riemannian spin manifold only one of which is conformally invariant. We present a straightforward exposition.

  12. All N=4 Conformal Supergravities

    CERN Document Server

    Butter, Daniel; de Wit, Bernard; Sahoo, Bindusar

    2016-01-01

    All N=4 conformal supergravities in four space-time dimensions are constructed. These are the only N=4 supergravity theories whose actions are invariant under off-shell supersymmetry. They are encoded in terms of a holomorphic function that is homogeneous of zeroth degree in scalar fields that parametrize an SU(1,1)/U(1) coset space. When this function equals a constant the Lagrangian is invariant under continuous SU(1,1) transformations.

  13. Conformal theory of galactic halos

    CERN Document Server

    Nesbet, R K

    2011-01-01

    Current cosmological theory describes an isolated galaxy as an observable central galaxy, surrounded by a large spherical halo attributed to dark matter. Galaxy formation by condensation of mass-energy out of a primordial uniform background is shown here to leave a scar, observed as a centripetal gravitational field halo in anomalous galactic rotation and in gravitational lensing. Conformal theory accounts for the otherwise counterintuitive centripetal effect.

  14. Anomalous Dimensions of Conformal Baryons

    CERN Document Server

    Pica, Claudio

    2016-01-01

    We determine the anomalous dimensions of baryon operators for the three color theory as function of the number of massless flavours within the conformal window to the maximum known order in perturbation theory. We show that the anomalous dimension of the baryon is controllably small for a wide range of number of flavours. We also find that this is always smaller than the anomalous dimension of the fermion mass operator. These findings challenge the partial compositeness paradigm.

  15. Exceptional and Spinorial Conformal Windows

    CERN Document Server

    Mojaza, Matin; Ryttov, Thomas A; Sannino, Francesco

    2012-01-01

    We study the conformal window of gauge theories containing fermionic matter fields, where the gauge group is any of the exceptional groups with the fermions transforming according to the fundamental and adjoint representations and the orthogonal groups where the fermions transform according to a spinorial representation. We investigate the phase diagram using a purely perturbative four loop analysis, the all-orders beta function and the ladder approximation.

  16. Holographic multiverse and conformal invariance

    Energy Technology Data Exchange (ETDEWEB)

    Garriga, Jaume [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08193 Barcelona (Spain); Vilenkin, Alexander, E-mail: jaume.garriga@ub.edu, E-mail: vilenkin@cosmos.phy.tufts.edu [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, 212 College Ave., Medford, MA 02155 (United States)

    2009-11-01

    We consider a holographic description of the inflationary multiverse, according to which the wave function of the universe is interpreted as the generating functional for a lower dimensional Euclidean theory. We analyze a simple model where transitions between inflationary vacua occur through bubble nucleation, and the inflating part of spacetime consists of de Sitter regions separated by thin bubble walls. In this model, we present some evidence that the dual theory is conformally invariant in the UV.

  17. Octonionic geometry and conformal transformations

    CERN Document Server

    Gogberashvili, Merab

    2016-01-01

    We describe space-time using split octonions over the reals and use their group of automorphisms, the non-compact form of Cartan's exceptional Lie group G2, as the main geometrical group of the model. It is studied connections of the G2-rotations of octonionic 8D space with the conformal transformations in 4D Minkowski space-time. It is shown that the dimensional constant needed in these analysis naturally gives the observed value of the cosmological constant.

  18. Electrophysiological precursors of social conformity.

    Science.gov (United States)

    Shestakova, Anna; Rieskamp, Jörg; Tugin, Sergey; Ossadtchi, Alexey; Krutitskaya, Janina; Klucharev, Vasily

    2013-10-01

    Humans often change their beliefs or behavior due to the behavior or opinions of others. This study explored, with the use of human event-related potentials (ERPs), whether social conformity is based on a general performance-monitoring mechanism. We tested the hypothesis that conflicts with a normative group opinion evoke a feedback-related negativity (FRN) often associated with performance monitoring and subsequent adjustment of behavior. The experimental results show that individual judgments of facial attractiveness were adjusted in line with a normative group opinion. A mismatch between individual and group opinions triggered a frontocentral negative deflection with the maximum at 200 ms, similar to FRN. Overall, a conflict with a normative group opinion triggered a cascade of neuronal responses: from an earlier FRN response reflecting a conflict with the normative opinion to a later ERP component (peaking at 380 ms) reflecting a conforming behavioral adjustment. These results add to the growing literature on neuronal mechanisms of social influence by disentangling the conflict-monitoring signal in response to the perceived violation of social norms and the neural signal of a conforming behavioral adjustment.

  19. Objective interpretation as conforming interpretation

    Directory of Open Access Journals (Sweden)

    Lidka Rodak

    2011-12-01

    Full Text Available The practical discourse willingly uses the formula of “objective interpretation”, with no regards to its controversial nature that has been discussed in literature.The main aim of the article is to investigate what “objective interpretation” could mean and how it could be understood in the practical discourse, focusing on the understanding offered by judicature.The thesis of the article is that objective interpretation, as identified with textualists’ position, is not possible to uphold, and should be rather linked with conforming interpretation. And what this actually implies is that it is not the virtue of certainty and predictability – which are usually associated with objectivity- but coherence that makes the foundation of applicability of objectivity in law.What could be observed from the analyses, is that both the phenomenon of conforming interpretation and objective interpretation play the role of arguments in the interpretive discourse, arguments that provide justification that interpretation is not arbitrary or subjective. With regards to the important part of the ideology of legal application which is the conviction that decisions should be taken on the basis of law in order to exclude arbitrariness, objective interpretation could be read as a question “what kind of authority “supports” certain interpretation”? that is almost never free of judicial creativity and judicial activism.One can say that, objective and conforming interpretation are just another arguments used in legal discourse.

  20. Conformal window and Landau singularities

    CERN Document Server

    Grunberg, G

    2001-01-01

    A physical characterization of Landau singularities is emphasized, which should trace the lower boundary N_f^* of the conformal window in QCD and supersymmetric QCD. A natural way to disentangle ``perturbative'' from ``non-perturbative'' contributions below N_f^* is suggested. Assuming an infrared fixed point is present in the perturbative part of the QCD coupling even in some range below N_f^* leads to the condition gamma(N_f^*)=1, where gamma is the critical exponent. Using the Banks-Zaks expansion, one gets 4conformal window. Some evidence for such a fixed point in QCD is provided through a modified Banks-Zaks expansion. Conformal window amplitudes, which contain power contributions, are show...

  1. 40 CFR 51.854 - Conformity analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Conformity analysis. 51.854 Section 51... FOR PREPARATION, ADOPTION, AND SUBMITTAL OF IMPLEMENTATION PLANS Determining Conformity of General Federal Actions to State or Federal Implementation Plans § 51.854 Conformity analysis. Link to...

  2. 40 CFR 52.2133 - General conformity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false General conformity. 52.2133 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS (CONTINUED) South Carolina § 52.2133 General conformity. The General Conformity regulations adopted into the South Carolina State Implementation Plan...

  3. 40 CFR 52.938 - General conformity.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false General conformity. 52.938 Section 52...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Kentucky § 52.938 General conformity. The General Conformity regulations were submitted on November 10, 1995, and adopted into the Kentucky...

  4. MIXED SELF-CONFORMAL MULTIFRACTAL MEASURES

    Institute of Scientific and Technical Information of China (English)

    Meifeng Dai

    2009-01-01

    Mixed multifractal analysis studies the simultaneous scaling behavior of finitely many measures. A self-conformal measure is a measure invariant under a set of conformal mappings. In this paper, we provide a description of the mixed multifractal theory of finitely many self-conformal measures.

  5. Recent Advances in Computational Conformal Geometry

    OpenAIRE

    Gu, Xianfeng David; Luo, Feng; Yau, Shing-Tung

    2009-01-01

    Computational conformal geometry focuses on developing the computational methodologies on discrete surfaces to discover conformal geometric invariants. In this work, we briefly summarize the recent developments for methods and related applications in computational conformal geometry. There are two major approaches, holomorphic differentials and curvature flow. Holomorphic differential method is a linear method, which is more efficient and robust to triangulations with lower qua...

  6. On the cohomology of Leibniz conformal algebras

    Science.gov (United States)

    Zhang, Jiao

    2015-04-01

    We construct a new cohomology complex of Leibniz conformal algebras with coefficients in a representation instead of a module. The low-dimensional cohomology groups of this complex are computed. Meanwhile, we construct a Leibniz algebra from a Leibniz conformal algebra and prove that the category of Leibniz conformal algebras is equivalent to the category of equivalence classes of formal distribution Leibniz algebras.

  7. Characterization of carbohydrates in rainwater from the southeastern North Carolina.

    Science.gov (United States)

    Mullaugh, Katherine M; Byrd, Jade N; Avery, G Brooks; Mead, Ralph N; Willey, Joan D; Kieber, Robert J

    2014-07-01

    Carbohydrates have been widely reported in atmospheric aerosols, but have not previously been quantified in rainwater. We have identified and quantified a series of 11 specific compounds including monosaccharides (glucose, fructose, arabinose, galactose and pinitol), disaccharides (sucrose and trehalose), sugar alcohols (arabitol, dulcitol and mannitol) and the anhydrosaccharide levoglucosan. Rainwater analyzed in this study includes 52 distinct precipitation events in Wilmington, NC between June 2011 and October 2012. Our analysis indicates carbohydrates typically contribute carbohydrates reached as high as 5.8 μM, with glucose and sucrose typically being the predominant species. The distribution of carbohydrates exhibited a distinct seasonal pattern, with higher concentrations of most carbohydrates, especially sucrose, in spring and summer, driven primarily by increased biogenic inputs during the growing season. Concentrations of carbohydrates were an order of magnitude higher in storms of terrestrial origin compared to marine events, further supporting a terrestrial biogenic origin of most species. Sequential sampling of Hurricane Irene showed significant quantities of carbohydrates present at the end of the storm when air mass back trajectories traversed over land. The highest level of levoglucosan, a compound associated with biomass burning, was detected in rain with an air mass back trajectory that traveled over a region affected by wildfires. When compared to aerosol concentrations reported by others, the sugar concentrations in rain demonstrate wet deposition is an important removal mechanism of this water-soluble and bioavailable fraction of atmospheric particulate organic matter.

  8. Assessing Bacterial Interactions Using Carbohydrate-Based Microarrays

    Directory of Open Access Journals (Sweden)

    Andrea Flannery

    2015-12-01

    Full Text Available Carbohydrates play a crucial role in host-microorganism interactions and many host glycoconjugates are receptors or co-receptors for microbial binding. Host glycosylation varies with species and location in the body, and this contributes to species specificity and tropism of commensal and pathogenic bacteria. Additionally, bacterial glycosylation is often the first bacterial molecular species encountered and responded to by the host system. Accordingly, characterising and identifying the exact structures involved in these critical interactions is an important priority in deciphering microbial pathogenesis. Carbohydrate-based microarray platforms have been an underused tool for screening bacterial interactions with specific carbohydrate structures, but they are growing in popularity in recent years. In this review, we discuss carbohydrate-based microarrays that have been profiled with whole bacteria, recombinantly expressed adhesins or serum antibodies. Three main types of carbohydrate-based microarray platform are considered; (i conventional carbohydrate or glycan microarrays; (ii whole mucin microarrays; and (iii microarrays constructed from bacterial polysaccharides or their components. Determining the nature of the interactions between bacteria and host can help clarify the molecular mechanisms of carbohydrate-mediated interactions in microbial pathogenesis, infectious disease and host immune response and may lead to new strategies to boost therapeutic treatments.

  9. Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity.

    Directory of Open Access Journals (Sweden)

    Alicja K Warda

    Full Text Available We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with 11 additional B. cereus reference genomes to provide an overview of the different types of carbohydrate transporters and utilization systems found in B. cereus strains. The combined application of API tests, defined growth media experiments and comparative genomics enabled us to link the carbohydrate utilisation capacity of 22 B. cereus strains with their genome content and in some cases to the panC phylogenetic grouping. A core set of carbohydrates including glucose, fructose, maltose, trehalose, N-acetyl-glucosamine, and ribose could be used by all strains, whereas utilisation of other carbohydrates like xylose, galactose, and lactose, and typical host-derived carbohydrates such as fucose, mannose, N-acetyl-galactosamine and inositol is limited to a subset of strains. Finally, the roles of selected carbohydrate transporters and utilisation systems in specific niches such as soil, foods and the human host are discussed.

  10. Hydrogen and methane breath tests for evaluation of resistant carbohydrates

    DEFF Research Database (Denmark)

    Rumessen, J J

    1992-01-01

    This review considers in detail the background, principles, techniques, limitations and advantages of the hydrogen and methane breath tests. Resistant food carbohydrates, defined as dietary carbohydrates partly or totally escaping small intestinal assimilation, are fermented in the human colon...... carbohydrates. Methane breath tests may supplement the information gained from hydrogen measurements, but further evaluations are needed. The hydrogen breath technique is rapid, simple and non-invasive as well as non-radioactive. It may be carried out in a large number of intact individuals under physiological...

  11. Simple mucin-type carbohydrate antigens in major salivary glands

    DEFF Research Database (Denmark)

    Therkildsen, M H; Mandel, U; Thorn, J

    1994-01-01

    -defined monoclonal antibodies (MAb) on frozen and paraffin-embedded normal salivary gland tissue from 22 parotid, 14 submandibular, six sublingual, and 13 labial glands to elucidate the simple mucin-type glycosylation pattern in relation to cyto- and histodifferentiation. The investigated carbohydrate structures......Simple mucin-type carbohydrate antigens Tn, sialosyl-Tn and T are often markers of neoplastic transformation and have very limited expression in normal tissues. We performed an immunohistological study of simple mucin-type carbohydrate antigens, including H and A variants, with well...... antigens indicates that these structures may be of value as markers of salivary gland tumors....

  12. PREPARATION OF CHEMICALLY WELL-DEFINED CARBOHYDRATE DENDRIMER CONJUGATES

    DEFF Research Database (Denmark)

    2004-01-01

    A method for the synthesis of dendrimer conjugates having a well-defined chemical structure, comprising one or more carbohydrate moieties and one or more immunomodulating substances coupled to a dendrimer, is presented. First, the carbohydrate is bound to the dendrimer in a chemoselective manner....... Subsequently, the immunomodulating substance is also bound in a chemoselective manner, to give a dendrimer conjugate with a well-defined structure and connectivity and containing a precise, pre-determined ratio of carbohydrate to immunomodulating substance. The invention also relates to novel dendrimer...

  13. Carbohydrate – protein complex of the waste of climacoptera obtusifolia

    Directory of Open Access Journals (Sweden)

    G. Seitimova

    2013-05-01

    Full Text Available Extract from Climacoptera obtusifolia family Chenopodiaceae has antidiabetic activity. For the first time carbohydrate-protein complex of the waste from Climacoptera obtusifolia was studied. It was found that the quantity of extractive substances with 80% ethanol in aerial part – 52;6% and in the waste – 12;35%. The technique of separation of the carbohydrate-protein complex from the waste from Climacoptera obtusifolia is developed by means of classical and physical-chemical methods. The composition of carbohydrate-protein complex was identified: oligosaccharide; polysaccharide and two glycoproteins.

  14. Carbohydrate metabolism and its regulatory hormones in anorexia nervosa.

    Science.gov (United States)

    Casper, R C

    1996-04-16

    Findings of studies of carbohydrate metabolism in anorexia nervosa are reviewed. Topics covered included fasting blood sugar concentrations; serum insulin concentrations, insulin receptor binding activity, insulin sensitivity, and insulin resistance; plasma ketone bodies and free fatty acids; glucose tolerance tests; growth hormone, cortisol, intestinal hormones, and norepinephrine. Metabolic changes reported in anorexia nervosa are similar to those found in human and animal studies of states of caloric and carbohydrate restriction. Restoration of normal body weight is associated with normalization of virtually all measures. It is concluded that published studies offer no conclusive evidence for a syndrome-specific impairment in carbohydrate metabolism in anorexia nervosa.

  15. Saturated fat, carbohydrates and cardiovascular disease.

    Science.gov (United States)

    Kuipers, R S; de Graaf, D J; Luxwolda, M F; Muskiet, M H A; Dijck-Brouwer, D A J; Muskiet, F A J

    2011-09-01

    The dietary intake of saturated fatty acids (SAFA) is associated with a modest increase in serum total cholesterol, but not with cardiovascular disease (CVD). Replacing dietary SAFA with carbohydrates (CHO), notably those with a high glycaemic index, is associated with an increase in CVD risk in observational cohorts, while replacing SAFA with polyunsaturated fatty acids (PUFA) is associated with reduced CVD risk. However, replacing a combination of SAFA and trans-fatty acids with n-6 PUFA (notably linoleic acid) in controlled trials showed no indication of benefit and a signal toward increased coronary heart disease risk, suggesting that n-3 PUFA may be responsible for the protective association between total PUFA and CVD. High CHO intakes stimulate hepatic SAFA synthesis and conservation of dietary SAFA . Hepatic de novo lipogenesis from CHO is also stimulated during eucaloric dietary substitution of SAFA by CHO with high glycaemic index in normo-insulinaemic subjects and during hypocaloric high-CHO/low-fat diets in subjects with the metabolic syndrome. The accumulation of SAFA stimulates chronic systemic low-grade inflammation through its mimicking of bacterial lipopolysaccharides and÷or the induction of other pro-inflammatory stimuli. The resulting systemic low-grade inflammation promotes insulin resistance, reallocation of energy-rich substrates and atherogenic dyslipidaemia that concertedly give rise to increased CVD risk. We conclude that avoidance of SAFA accumulation by reducing the intake of CHO with high glycaemic index is more effective in the prevention of CVD than reducing SAFA intake per se.

  16. Relation between the secondary structure of carbohydrate residues of alpha1-acid glycoprotein (orosomucoid) and the fluorescence of the protein.

    Science.gov (United States)

    Albani, Jihad R

    2003-05-01

    We studied in this work the relation that exists between the secondary structure of the glycans of alpha(1)-acid glycoprotein and the fluorescence of the Trp residues of the protein. We calculated for that the efficiency of quenching and the radiative and non-radiative constants. Our results indicate that the glycans display a spatial structure that is modified upon asialylation. The asialylated conformation is closer to the protein matrix than the sialylated form, inducing by that a decrease in the fluorescence parameters of the Trp residues. In fact, the mean quantum yield of Trp residues in sialylated and asialylated alpha(1)-acid glycoprotein are 0.0645 and 0.0385, respectively. Analysis of the fluorescence emission of alpha(1)-acid glycoprotein as the result of two contributions (surface and hydrophobic domains) indicates that quantum yields of both classes of Trp residues are lower when the protein is in the asialylated form. Also, the mean fluorescence lifetime of Trp residues decreases from 2.285 ns in the sialylated protein to 1.948 ns in the asialylated one. The radiative rate constant k(r) of the Trp residues in the sialylated alpha(1)-acid glycoprotein is higher than that in the asialylated protein. Thus, the carbohydrate residues are closer to the Trp residues in the absence of sialic acid. The modification of the spatial conformation of the glycans upon asialylation is confirmed by the decrease of the fluorescence lifetimes of Calcofluor, a fluorophore that binds to the carbohydrate residues. Finally, thermal intensity quenching of Calcofluor bound to alpha(1)-acid glycoprotein shows that the carbohydrate residues have slower residual motions in the absence of sialic acid residues.

  17. Families and degenerations of conformal field theories

    Energy Technology Data Exchange (ETDEWEB)

    Roggenkamp, D.

    2004-09-01

    In this work, moduli spaces of conformal field theories are investigated. In the first part, moduli spaces corresponding to current-current deformation of conformal field theories are constructed explicitly. For WZW models, they are described in detail, and sigma model realizations of the deformed WZW models are presented. The second part is devoted to the study of boundaries of moduli spaces of conformal field theories. For this purpose a notion of convergence of families of conformal field theories is introduced, which admits certain degenerated conformal field theories to occur as limits. To such a degeneration of conformal field theories, a degeneration of metric spaces together with additional geometric structures can be associated, which give rise to a geometric interpretation. Boundaries of moduli spaces of toroidal conformal field theories, orbifolds thereof and WZW models are analyzed. Furthermore, also the limit of the discrete family of Virasoro minimal models is investigated. (orig.)

  18. Gauge Choice in Conformal Gravity

    Science.gov (United States)

    Sultana, Joseph; Kazanas, Demosthenes

    2017-01-01

    In a recent paper (MNRAS 458, 4122 (2016)) K. Horne examined the effect of a conformally coupled scalar field (referred to as Higgs field) on the Mannheim-Kazanas metric gμν, i.e. the static spherically symmetric metric within the context of conformal gravity (CG), and studied its effect on the rotation curves of galaxies. He showed that for a Higgs field of the form S(r) = S0a/(r + a), where a is a radial length scale, the equivalent Higgs-frame Mannheim-Kazanas metric tilde{g}_{μ ν } = Ω ^2 g_{μ ν }, with Ω = S(r)/S0, lacks the linear γr term, which has been employed in the fitting of the galactic rotation curves without the need to invoke dark matter. In this brief note we point out that the representation of the Mannheim-Kazanas metric in a gauge where it lacks the linear term has already been presented by others, including Mannheim and Kazanas themselves, without the need to introduce a conformally coupled Higgs field. Furthermore, Horne argues that the absence of the linear term resolves the issue of light bending in the wrong direction, i.e. away from the gravitating mass, if γr > 0 in the Mannheim-Kazanas metric, a condition necessary to resolve the galactic dynamics in the absence of dark matter. In this case we also point out that the elimination of the linear term is not even required because the sign of the γr term in the metric can be easily reversed by a simple gauge transformation, and also that the effects of this term are indeed too small to be observed.

  19. The biological bases of conformity.

    Science.gov (United States)

    Morgan, T J H; Laland, K N

    2012-01-01

    Humans are characterized by an extreme dependence on culturally transmitted information and recent formal theory predicts that natural selection should favor adaptive learning strategies that facilitate effective copying and decision making. One strategy that has attracted particular attention is conformist transmission, defined as the disproportionately likely adoption of the most common variant. Conformity has historically been emphasized as significant in the social psychology literature, and recently there have also been reports of conformist behavior in non-human animals. However, mathematical analyses differ in how important and widespread they expect conformity to be, and relevant experimental work is scarce, and generates findings that are both mutually contradictory and inconsistent with the predictions of the models. We review the relevant literature considering the causation, function, history, and ontogeny of conformity, and describe a computer-based experiment on human subjects that we carried out in order to resolve ambiguities. We found that only when many demonstrators were available and subjects were uncertain was subject behavior conformist. A further analysis found that the underlying response to social information alone was generally conformist. Thus, our data are consistent with a conformist use of social information, but as subjects' behavior is the result of both social and asocial influences, the resultant behavior may not be conformist. We end by relating these findings to an embryonic cognitive neuroscience literature that has recently begun to explore the neural bases of social learning. Here conformist transmission may be a particularly useful case study, not only because there are well-defined and tractable opportunities to characterize the biological underpinnings of this form of social learning, but also because early findings imply that humans may possess specific cognitive adaptations for effective social learning.

  20. The Biological Bases of Conformity

    Directory of Open Access Journals (Sweden)

    Thomas Joshau Henry Morgan

    2012-06-01

    Full Text Available Humans are characterized by an extreme dependence on culturally transmitted information and recent formal theory predicts that natural selection should favour adaptive learning strategies that facilitate effective use of social information in decision making. One strategy that has attracted particular attention is conformist transmission, defined as the disproportionately likely adoption of the most common variant. Conformity has historically been emphasized as significant in the social psychology literature, and recently there have also been reports of conformist behaviour in nonhuman animals. However, mathematical analyses differ in how important and widespread they expect conformity to be, and relevant experimental work is scarce, and generates findings that are both mutually contradictory and inconsistent with the predictions of the models. We review the relevant literature considering the causation, function, history and ontogeny of conformity and describe a computer-based experiment on human subjects that we carried out in order to resolve ambiguities. We found that only when many demonstrators were available and subjects were uncertain was subject behaviour conformist. A further analysis found that the underlying response to social information alone was generally conformist. Thus, our data are consistent with a conformist use of social information, but as subject’s behaviour is the result of both social and asocial influences, the resultant behaviour may not be conformist. We end by relating these findings to an embryonic cognitive neuroscience literature that has recently begun to explore the neural bases of social learning. Here conformist transmission may be a particularly useful case study, not only because there are well-defined and tractable opportunities to characterize the biological underpinnings of this form of social learning, but also because early findings imply that humans may possess specific cognitive adaptations for

  1. Conformance Testing: Measurement Decision Rules

    Science.gov (United States)

    Mimbs, Scott M.

    2010-01-01

    The goal of a Quality Management System (QMS) as specified in ISO 9001 and AS9100 is to provide assurance to the customer that end products meet specifications. Measuring devices, often called measuring and test equipment (MTE), are used to provide the evidence of product conformity to specified requirements. Unfortunately, processes that employ MTE can become a weak link to the overall QMS if proper attention is not given to the measurement process design, capability, and implementation. Documented "decision rules" establish the requirements to ensure measurement processes provide the measurement data that supports the needs of the QMS. Measurement data are used to make the decisions that impact all areas of technology. Whether measurements support research, design, production, or maintenance, ensuring the data supports the decision is crucial. Measurement data quality can be critical to the resulting consequences of measurement-based decisions. Historically, most industries required simplistic, one-size-fits-all decision rules for measurements. One-size-fits-all rules in some cases are not rigorous enough to provide adequate measurement results, while in other cases are overly conservative and too costly to implement. Ideally, decision rules should be rigorous enough to match the criticality of the parameter being measured, while being flexible enough to be cost effective. The goal of a decision rule is to ensure that measurement processes provide data with a sufficient level of quality to support the decisions being made - no more, no less. This paper discusses the basic concepts of providing measurement-based evidence that end products meet specifications. Although relevant to all measurement-based conformance tests, the target audience is the MTE end-user, which is anyone using MTE other than calibration service providers. Topics include measurement fundamentals, the associated decision risks, verifying conformance to specifications, and basic measurement

  2. Carbohydrate biomarkers for future disease detection and treatment

    Institute of Scientific and Technical Information of China (English)

    REID; Suazette

    2010-01-01

    Carbohydrates are considered as one of the most important classes of biomarkers for cell types,disease states,protein functions,and developmental states.Carbohydrate"binders"that can specifically recognize a carbohydrate biomarker can be used for developing novel types of site specific delivery methods and imaging agents.In this review,we present selected examples of important carbohydrate biomarkers and how they can be targeted for the development of therapeutic and diagnostic agents.Examples are arranged based on disease categories including(1) infectious diseases,(2) cancer,(3) inflammation and immune responses,(4) signal transduction,(5) stem cell transformation,(6) embryo development,and(7) cardiovascular diseases,though some issues cross therapeutic boundaries.

  3. Nonstructural carbohydrates and return bloom potential differ among cranberry cultivars

    Science.gov (United States)

    explain low fruit set and biennial bearing tendencies of cranberry (Vaccinium macrocarpon). Yet, comparisons of nonstructural carbohydrate concentrations during critical phenological stages across cultivars that differ in biennial bearing tendencies and return bloom potential are lacking, particular...

  4. Toward TeV Conformality

    Energy Technology Data Exchange (ETDEWEB)

    Appelquist, T; Avakian, A; Babich, R; Brower, R C; Cheng, M; Clark, M A; Cohen, S D; Fleming, G T; Kiskis, J; Neil, E T; Osborn, J C; Rebbi, C; Schaich, D; Soltz, R; Vranas, P

    2009-11-30

    We study the chiral condensate <{bar {psi}}{psi}> for an SU(3) gauge theory with N{sub f} massless Dirac fermions in the fundamental representation when N{sub f} is increased from 2 to 6. For N{sub f} = 2, our lattice simulations of <{bar {psi}}{psi}>/F{sup 3}, where F is the Nambu-Goldstone-boson decay constant, agree with the measured QCD value. For N{sub f} = 6, this ratio shows significant enhancement, presaging an even larger enhancement anticipated as N{sub f} increases further, toward the critical value for transition from confinement to infrared conformality.

  5. From conformal to Einstein gravity

    Science.gov (United States)

    Anastasiou, Giorgos; Olea, Rodrigo

    2016-10-01

    We provide a simple derivation of the equivalence between Einstein and conformal gravity (CG) with Neumann boundary conditions given by Maldacena. As Einstein spacetimes are Bach flat, a generic solution to CG would contain both Einstein and non-Einstein parts. Using this decomposition of the spacetime curvature in the Weyl tensor makes manifest the equivalence between the two theories, both at the level of the action and the variation of it. As a consequence, we show that the on-shell action for critical gravity in four dimensions is given uniquely in terms of the Bach tensor.

  6. From Conformal to Einstein Gravity

    CERN Document Server

    Anastasiou, Giorgos

    2016-01-01

    We provide a simple derivation of the equivalence between Einstein and Conformal Gravity (CG) with Neumann boundary conditions given by Maldacena. As Einstein spacetimes are Bach flat, a generic solution to CG would contain both Einstein and non-Einstein part. Using this decomposition of the spacetime curvature in the Weyl tensor, makes manifest the equivalence between the two theories, both at the level of the action and the variation of it. As a consequence, we show that the on-shell action for Critical Gravity in four dimensions is given uniquely in terms of the Bach tensor.

  7. Effect of the carbohydrate moiety on the secondary structure of beta 2-glycoprotein. I. Implications for the biosynthesis and folding of glycoproteins.

    Science.gov (United States)

    Walsh, M T; Watzlawick, H; Putnam, F W; Schmid, K; Brossmer, R

    1990-07-01

    By use of six highly purified exoglycosidases with well-defined specificity, the oligosaccharide units of human plasma beta 2-glycoprotein I (beta 2I) were modified by sequential enzymatic degradation. The released monosaccharides (NeuAc, Gal, GlcNAc, and Man) were quantified, and the carbohydrate compositions of the resulting glycoprotein (gp) derivatives were determined. The gp was found to be both partially sialylated and galactosylated. These findings which are in agreement with earlier reports suggest that the carbohydrate moiety of beta 2I possesses more bi- than tri-antennas, probably three of the former and two of the latter carbohydrate units. Circular dichroic (CD) spectra of native beta 2I and its derivatives were measured in aqueous buffer and 2-chloroethanol (2-CE). Analysis of these spectra for elements of secondary structure showed beta 2I and most of the derivatives to contain predominantly beta-sheet and beta-turn structures. The lack of alpha-helical structures in aqueous buffer was noted. Removal of a large portion of the carbohydrate moiety did not alter the CD spectra or secondary structure of beta 2I in either aqueous buffer or in 2-CE. However, after enzymatic removal of approximately 96% of the carbohydrate moiety, large significant changes in the spectra and secondary structures were observed. In aqueous buffer a shift in the wavelength minimum occurred, accompanied by an increase in the magnitude of the molar ellipticity and the amount of beta-turn, with a reduction in random coil. One-third of the amino acids which were originally in random coil conformation assumed beta-turns after removal of 96% of the carbohydrate moiety.(ABSTRACT TRUNCATED AT 250 WORDS)

  8. Sensitive carbohydrate detection using surface enhanced Raman tagging.

    Science.gov (United States)

    Vangala, Karthikeshwar; Yanney, Michael; Hsiao, Cheng-Te; Wu, Wells W; Shen, Rong-Fong; Zou, Sige; Sygula, Andrzej; Zhang, Dongmao

    2010-12-15

    Glycomic analysis is an increasingly important field in biological and biomedical research as glycosylation is one of the most important protein post-translational modifications. We have developed a new technique to detect carbohydrates using surface enhanced Raman spectroscopy (SERS) by designing and applying a Rhodamine B derivative as the SERS tag. Using a reductive amination reaction, the Rhodamine-based tag (RT) was successfully conjugated to three model carbohydrates (glucose, lactose, and glucuronic acid). SERS detection limits obtained with a 633 nm HeNe laser were ∼1 nM in concentration for all the RT-carbohydrate conjugates and ∼10 fmol in total sample consumption. The dynamic range of the SERS method is about 4 orders of magnitude, spanning from 1 nM to 5 μM. Ratiometric SERS quantification using isotope-substituted SERS internal references allows comparative quantifications of carbohydrates labeled with RT and deuterium/hydrogen substituted RT tags, respectively. In addition to enhancing the SERS detection of the tagged carbohydrates, the Rhodamine tagging facilitates fluorescence and mass spectrometric detection of carbohydrates. Current fluorescence sensitivity of RT-carbohydrates is ∼3 nM in concentration while the mass spectrometry (MS) sensitivity is about 1 fmol, achieved with a linear ion trap electrospray ionization (ESI)-MS instrument. Potential applications that take advantage of the high SERS, fluorescence, and MS sensitivity of this SERS tagging strategy are discussed for practical glycomic analysis where carbohydrates may be quantified with a fluorescence and SERS technique and then identified with ESI-MS techniques.

  9. The role of carbohydrates in infection strategies of enteric pathogens.

    Science.gov (United States)

    Kato, Kentaro; Ishiwa, Akiko

    2015-03-01

    Enteric pathogens cause considerable public health concerns worldwide including tropical regions. Here, we review the roles of carbohydrates in the infection strategies of various enteric pathogens including viruses, bacteria and protozoa, which infect the epithelial lining of the human and animal intestine. At host cell entry, enteric viruses, including norovirus, recognize mainly histo-blood group antigens. At the initial step of bacterial infections, carbohydrates also function as receptors for attachment. Here, we describe the function of carbohydrates in infection by Salmonella enterica and several bacterial species that produce a variety of fimbrial adhesions. During invasion by enteropathogenic protozoa, apicomplexan parasites utilize sialic acids or sulfated glycans. Carbohydrates serve as receptors for infection by these microbes; however, their usage of carbohydrates varies depending on the microbe. On the surface of the mucosal tissues of the gastrointestinal tract, various carbohydrate moieties are present and play a crucial role in infection, representing the site of infection or route of access for most microbes. During the infection and/or invasion process of the microbes, carbohydrates function as receptors for various microbes, but they can also function as a barrier to infection. One approach to develop effective prophylactic and therapeutic antimicrobial agents is to modify the drug structure. Another approach is to modify the mode of inhibition of infection depending on the individual pathogen by using and mimicking the interactions with carbohydrates. In addition, similarities in mode of infection may also be utilized. Our findings will be useful in the development of new drugs for the treatment of enteric pathogens.

  10. Validation of lignocellulosic biomass carbohydrates determination via acid hydrolysis.

    Science.gov (United States)

    Zhou, Shengfei; Runge, Troy M

    2014-11-04

    This work studied the two-step acid hydrolysis for determining carbohydrates in lignocellulosic biomass. Estimation of sugar loss based on acid hydrolyzed sugar standards or analysis of sugar derivatives was investigated. Four model substrates (starch, holocellulose, filter paper and cotton) and three levels of acid/material ratios (7.8, 10.3 and 15.4, v/w) were studied to demonstrate the range of test artifacts. The method for carbohydrates estimation based on acid hydrolyzed sugar standards having the most satisfactory carbohydrate recovery and relative standard deviation. Raw material and the acid/material ratio both had significant effect on carbohydrate hydrolysis, suggesting the acid to have impacts beyond a catalyst in the hydrolysis. Following optimal procedures, we were able to reach a carbohydrate recovery of 96% with a relative standard deviation less than 3%. The carbohydrates recovery lower than 100% was likely due to the incomplete hydrolysis of substrates, which was supported by scanning electron microscope (SEM) images.

  11. Simulation of carbohydrates, from molecular docking to dynamics in water.

    Science.gov (United States)

    Sapay, Nicolas; Nurisso, Alessandra; Imberty, Anne

    2013-01-01

    Modeling of carbohydrates is particularly challenging because of the variety of structures resulting for the high number of monosaccharides and possible linkages and also because of their intrinsic flexibility. The development of carbohydrate parameters for molecular modeling is still an active field. Nowadays, main carbohydrates force fields are GLYCAM06, CHARMM36, and GROMOS 45A4. GLYCAM06 includes the largest choice of compounds and is compatible with the AMBER force fields and associated. Furthermore, AMBER includes tools for the implementation of new parameters. When looking at protein-carbohydrate interaction, the choice of the starting structure is of importance. Such complex can be sometimes obtained from the Protein Data Bank-although the stereochemistry of sugars may require some corrections. When no experimental data is available, molecular docking simulation is generally used to the obtain protein-carbohydrate complex coordinates. As molecular docking parameters are not specifically dedicated to carbohydrates, inaccuracies should be expected, especially for the docking of polysaccharides. This issue can be addressed at least partially by combining molecular docking with molecular dynamics simulation in water.

  12. Bacterial, plant, and fungal carbohydrate structure databases: daily usage.

    Science.gov (United States)

    Toukach, Philip V; Egorova, Ksenia S

    2015-01-01

    Natural carbohydrates play important roles in living systems and therefore are used as diagnostic and therapeutic targets. The main goal of glycomics is systematization of carbohydrates and elucidation of their role in human health and disease. The amount of information on natural carbohydrates accumulates rapidly, but scientists still lack databases and computer-assisted tools needed for orientation in the glycomic information space. Therefore, freely available, regularly updated, and cross-linked databases are demanded. Bacterial Carbohydrate Structure Database (Bacterial CSDB) was developed for provision of structural, bibliographic, taxonomic, NMR spectroscopic, and other related information on bacterial and archaeal carbohydrate structures. Its main features are (1) coverage above 90%, (2) high data consistence (above 90% of error-free records), and (3) presence of manually verified bibliographic, NMR spectroscopic, and taxonomic annotations. Recently, CSDB has been expanded to cover carbohydrates of plant and fungal origin. The achievement of full coverage in the plant and fungal domains is expected in the future. CSDB is freely available on the Internet as a web service at http://csdb.glycoscience.ru. This chapter aims at showing how to use CSDB in your daily scientific practice.

  13. Carbohydrate-based nanoparticles for potential applications in medicine.

    Science.gov (United States)

    Marradi, Marco; García, Isabel; Penadés, Soledad

    2011-01-01

    Although carbohydrates are essential for life, the development of medical tools based on these important biomolecules is significantly slower than those based on proteins or nucleic acids. This chapter deals with the applications of nanoparticles decorated with carbohydrates and discusses the perspectives of their use in the field of medicine. The review is divided into two sections: diagnosis and therapy. Within these topics, the focus will be on two main types of systems: carbohydrate-coated metallic nanoparticles in which the carbohydrate ligands are "covalently" linked to a nanosized metallic cluster and polysaccharide-encapsulated metallic cores. The former glyconanoparticles (GNPs) represent a powerful chemical tool in the field of glycobiology as a specific carbohydrate can be selected to exert a concrete biological function and profile carbohydrate-based interactions. Up to now, these GNPs have been mainly used as potential anti-adhesion agents against pathogens. The opportunity of inserting multifunctionality and changing the nucleus size/material is giving birth to new targeted systems for imaging and therapy. On the other hand, nonmetallic polysaccharide-based nanoparticles have been successfully used as drug delivery carriers in addition to molecular imaging.

  14. Signal Amplification by Glyco-qPCR for Ultrasensitive Detection of Carbohydrates: Applications in Glycobiology**

    OpenAIRE

    Kwon, Seok Joon; Lee, Kyung Bok; Solakyildirim, Kemal; Masuko, Sayaka; Ly, Mellisa; Zhang, Fuming; Li, Lingyun; Dordick, Jonathan S.; Robert J Linhardt

    2012-01-01

    Tiny amounts of carbohydrates (ca. 1 zmol) can be detected quantitatively by a real-time method based on the conjugation of carbohydrates with DNA markers (see picture). The proposed method (glyco-qPCR) provides uniform, ultrasensitive detection of carbohydrates, which can be applied to glycobiology, as well as carbohydrate-based drug discovery.

  15. Unique conformer selection of human growth-regulatory lectin galectin-1 for ganglioside GM1 versus bacterial toxins.

    Science.gov (United States)

    Siebert, Hans-Christian; André, Sabine; Lu, Shan-Yun; Frank, Martin; Kaltner, Herbert; van Kuik, J Albert; Korchagina, Elena Y; Bovin, Nicolai; Tajkhorshid, Emad; Kaptein, Robert; Vliegenthart, Johannes F G; von der Lieth, Claus-Wilhelm; Jiménez-Barbero, Jesús; Kopitz, Jürgen; Gabius, Hans-Joachim

    2003-12-23

    Endogenous lectins induce effects on cell growth by binding to antennae of natural glycoconjugates. These complex carbohydrates often present more than one potential lectin-binding site in a single chain. Using the growth-regulatory interaction of the pentasaccharide of ganglioside GM(1) with homodimeric galectin-1 on neuroblastoma cell surfaces as a model, we present a suitable strategy for addressing this issue. The approach combines NMR spectroscopic and computational methods and does not require isotope-labeled glycans. It involves conformational analysis of the two building blocks of the GM(1) glycan, i.e., the disaccharide Galbeta1-3GalNAc and the trisaccharide Neu5Acalpha2-3Galbeta1-4Glc. Their bound-state conformations were determined by transferred nuclear Overhauser enhancement spectroscopy. Next, measurements on the lectin-pentasaccharide complex revealed differential conformer selection regarding the sialylgalactose linkage in the tri- versus pentasaccharide (Phi and Psi value of -70 degrees and 15 degrees vs 70 degrees and 15 degrees, respectively). To proceed in the structural analysis, the characteristic experimentally detected spatial vicinity of a galactose unit and Trp68 in the galectin's binding site offered a means, exploiting saturation transfer from protein to carbohydrate protons. Indeed, we detected two signals unambiguously assigned to the terminal Gal and the GalNAc residues. Computational docking and interaction energy analyses of the entire set of ligands supported and added to experimental results. The finding that the ganglioside's carbohydrate chain is subject to differential conformer selection at the sialylgalactose linkage by galectin-1 and GM(1)-binding cholera toxin (Phi and Psi values of -172 degrees and -26 degrees, respectively) is relevant for toxin-directed drug design. In principle, our methodology can be applied in studies aimed at blocking galectin functionality in malignancy and beyond glycosciences.

  16. Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

    Energy Technology Data Exchange (ETDEWEB)

    Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas, E-mail: tke@uams.edu [Winthrop P. Rockefeller Cancer Institute and Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR 72205 (United States)

    2011-11-11

    Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

  17. Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

    Directory of Open Access Journals (Sweden)

    Thomas Kieber-Emmons

    2011-11-01

    Full Text Available Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs. To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I, and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses.

  18. Carbohydrate Mimetic Peptides Augment Carbohydrate-Reactive Immune Responses in the Absence of Immune Pathology

    Science.gov (United States)

    Hennings, Leah; Artaud, Cecile; Jousheghany, Fariba; Monzavi-Karbassi, Behjatolah; Pashov, Anastas; Kieber-Emmons, Thomas

    2011-01-01

    Among the most challenging of clinical targets for cancer immunotherapy are Tumor Associated Carbohydrate Antigens (TACAs). To augment immune responses to TACA we are developing carbohydrate mimetic peptides (CMPs) that are sufficiently potent to activate broad-spectrum anti-tumor reactivity. However, the activation of immune responses against terminal mono- and disaccharide constituents of TACA raises concerns regarding the balance between “tumor destruction” and “tissue damage”, as mono- and disaccharides are also expressed on normal tissue. To support the development of CMPs for clinical trial testing, we demonstrate in preclinical safety assessment studies in mice that vaccination with CMPs can enhance responses to TACAs without mediating tissue damage to normal cells expressing TACA. BALB/c mice were immunized with CMPs that mimic TACAs reactive with Griffonia simplicifolia lectin 1 (GS-I), and tissue reactivity of serum antibodies were compared with the tissue staining profile of GS-I. Tissues from CMP immunized mice were analyzed using hematoxylin and eosin stain, and Luxol-fast blue staining for myelination. Western blots of membranes from murine mammary 4T1 cells, syngeneic with BALB/c mice, were also compared using GS-I, immunized serum antibodies, and naive serum antibodies. CMP immunization enhanced glycan reactivities with no evidence of pathological autoimmunity in any immunized mice demonstrating that tissue damage is not an inevitable consequence of TACA reactive responses. PMID:24213131

  19. Magnesium and disturbances in carbohydrate metabolism.

    Science.gov (United States)

    Mooren, Frank C

    2015-09-01

    Magnesium is actively involved in a number of metabolic reactions as an important co-factor, with special emphasis on carbohydrate metabolism. After a brief overview of the regulation of intra- and extracellular magnesium, the present review first describes the regulatory role of magnesium in important metabolic pathways involved in energy metabolism and glycaemic control. Next the clinical significance of hypomagnesaemic conditions with regard to the management of glucose in prediabetic stages, such as insulin resistance/impaired glucose tolerance and in type 2 diabetes mellitus are characterized. Cross-sectional as well as longitudinal studies suggest that a reduced dietary magnesium intake serves as a risk factor for the incidence of both impaired glucose regulation and type 2 diabetes. Mechanisms that might be responsible for diabetes-associated hypomagnesaemia are discussed. Furthermore, the role of hypomagnesaemia in the development and progression of chronic diabetic complications are addressed. Finally, the available literature on the effects of magnesium supplementation on glycaemic control parameters during prediabetic conditions (preventive approach) as well as type 2 diabetes mellitus (therapeutic approach) are reviewed systematically. There is considerable evidence that chronic magnesium supplementation may delay the progression from impaired glucose regulation to type 2 diabetes; however, the effects of oral magnesium supplementation as an adjunct therapy for type 2 diabetes are quite heterogeneous with respect to the various measures of glycaemic control. The results of this review suggest a requirement for critical consideration of the pros and cons of magnesium replacement therapy, based on variables such as magnesium status, stage of disease and glycaemic control.

  20. Holography and Conformal Anomaly Matching

    CERN Document Server

    Cabo-Bizet, Alejandro; Narain, K S

    2013-01-01

    We discuss various issues related to the understanding of the conformal anomaly matching in CFT from the dual holographic viewpoint. First, we act with a PBH diffeomorphism on a generic 5D RG flow geometry and show that the corresponding on-shell bulk action reproduces the Wess-Zumino term for the dilaton of broken conformal symmetry, with the expected coefficient aUV-aIR. Then we consider a specific 3D example of RG flow whose UV asymptotics is normalizable and admits a 6D lifting. We promote a modulus \\rho appearing in the geometry to a function of boundary coordinates. In a 6D description {\\rho} is the scale of an SU(2) instanton. We determine the smooth deformed background up to second order in the space-time derivatives of \\rho and find that the 3D on-shell action reproduces a boundary kinetic term for the massless field \\tau= log(\\rho) with the correct coefficient \\delta c=cUV-cIR. We further analyze the linearized fluctuations around the deformed background geometry and compute the one-point functions ...

  1. A conformal block Farey tail

    CERN Document Server

    Maloney, Alexander; Ng, Gim Seng

    2016-01-01

    We investigate the constraints of crossing symmetry on CFT correlation functions. Four point conformal blocks are naturally viewed as functions on the upper-half plane, on which crossing symmetry acts by PSL(2,Z) modular transformations. This allows us to construct a unique, crossing symmetric function out of a given conformal block by averaging over PSL(2,Z). In some two dimensional CFTs the correlation functions are precisely equal to the modular average of the contributions of a finite number of light states. For example, in the two dimensional Ising and tri-critical Ising model CFTs, the correlation functions of identical operators are equal to the PSL(2,Z) average of the Virasoro vacuum block; this determines the 3 point function coefficients uniquely in terms of the central charge. The sum over PSL(2,Z) in CFT2 has a natural AdS3 interpretation as a sum over semi-classical saddle points, which describe particles propagating along rational tangles in the bulk. We demonstrate this explicitly for the corre...

  2. Modified carbohydrate-chitosan compounds, methods of making the same and methods of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, Richard A; Pawlak, Joel J; Salam, Abdus; El-Tahlawy, Khaled Fathy

    2015-03-10

    Compositions of matter are provided that include chitosan and a modified carbohydrate. The modified carbohydrate includes a carbohydrate component and a cross linking agent. The modified carbohydrate has increased carboxyl content as compared to an unmodified counterpart carbohydrate. A carboxyl group of the modified carbohydrate is covalently bonded with an amino group of chitosan. The compositions of matter provided herein may include cross linked starch citrate-chitosan and cross linked hemicellulose citrate-chitosan, including foams thereof. These compositions yield excellent absorbency and metal chelation properties. Methods of making cross linked modified carbohydrate-chitosan compounds are also provided.

  3. Conformal submanifold geometry I-III

    CERN Document Server

    Burstall, Francis E

    2010-01-01

    In Part I, we develop the notions of a Moebius structure and a conformal Cartan geometry, establish an equivalence between them; we use them in Part II to study submanifolds of conformal manifolds in arbitrary dimension and codimension. We obtain Gauss-Codazzi-Ricci equations and a conformal Bonnet theorem characterizing immersed submanifolds of the conformal n-sphere. These methods are applied in Part III to study constrained Willmore surfaces, isothermic surfaces, Guichard surfaces and conformally-flat submanifolds with flat normal bundle, and their spectral deformations, in arbitrary codimension. The high point of these applications is a unified theory of Moebius-flat submanifolds, which include Guichard surfaces and conformally flat hypersurfaces.

  4. Simulating Protein Conformations through Global Optimization

    CERN Document Server

    Mucherino, A; Pardalos, P M

    2008-01-01

    Many researches have been working on the protein folding problem from more than half century. Protein folding is indeed one of the major unsolved problems in science. In this work, we discuss a model for the simulation of protein conformations. This simple model is based on the idea of imposing few geometric requirements on chains of atoms representing the backbone of a protein conformation. The model leads to the formulation of a global optimization problem, whose solutions correspond to conformations satisfying the desired requirements. The global optimization problem is solved by the recently proposed Monkey Search algorithm. The simplicity of the optimization problem and the effectiveness of the used meta-heuristic search allowed the simulation of a large set of high-quality conformations. We show that, even though only few geometric requirements are imposed, some of the simulated conformation results to be similar (in terms of RMSD) to conformations real proteins actually have in nature.

  5. Conformal symmetries of FRW accelerating cosmologies

    Energy Technology Data Exchange (ETDEWEB)

    Kehagias, A. [Physics Division, National Technical University of Athens, 15780 Zografou Campus, Athens (Greece); Department of Theoretical Physics and Center for Astroparticle Physics (CAP) 24 quai E. Ansermet, CH-1211 Geneva 4 (Switzerland); Riotto, A. [Department of Theoretical Physics and Center for Astroparticle Physics (CAP) 24 quai E. Ansermet, CH-1211 Geneva 4 (Switzerland)

    2014-07-15

    We show that any accelerating Friedmann–Robertson–Walker (FRW) cosmology with equation of state w<−1/3 (and therefore not only a de Sitter stage with w=−1) exhibits three-dimensional conformal symmetry on future constant-time hypersurfaces if the bulk theory is invariant under bulk conformal Killing vectors. We also offer an alternative derivation of this result in terms of conformal Killing vectors and show that long wavelength comoving curvature perturbations of the perturbed FRW metric are just conformal Killing motions of the FRW background. We then extend the boundary conformal symmetry to the bulk for accelerating cosmologies. Our findings indicate that one can easily generate perturbations of scalar fields which are not only scale invariant, but also fully conformally invariant on super-Hubble scales. Measuring a scale-invariant power spectrum for the cosmological perturbation does not automatically imply that the universe went through a de Sitter stage.

  6. Axial symmetry and conformal Killing vectors

    CERN Document Server

    Mars, M; Mars, Marc; Senovilla, Jose M.M.

    1993-01-01

    Axisymmetric spacetimes with a conformal symmetry are studied and it is shown that, if there is no further conformal symmetry, the axial Killing vector and the conformal Killing vector must commute. As a direct consequence, in conformally stationary and axisymmetric spacetimes, no restriction is made by assuming that the axial symmetry and the conformal timelike symmetry commute. Furthermore, we prove that in axisymmetric spacetimes with another symmetry (such as stationary and axisymmetric or cylindrically symmetric spacetimes) and a conformal symmetry, the commutator of the axial Killing vector with the two others mush vanish or else the symmetry is larger than that originally considered. The results are completely general and do not depend on Einstein's equations or any particular matter content.

  7. Conformational changes in glycine tri- and hexapeptide

    DEFF Research Database (Denmark)

    Yakubovich, Alexander V.; Solov'yov, Ilia; Solov'yov, Andrey V.

    2006-01-01

    conformations and calculated the energy barriers for transitions between them. Using a thermodynamic approach, we have estimated the times of the characteristic transitions between these conformations. The results of our calculations have been compared with those obtained by other theoretical methods...... also investigated the influence of the secondary structure of polypeptide chains on the formation of the potential energy landscape. This analysis has been performed for the sheet and the helix conformations of chains of six amino acids....

  8. Conformal Invariance and Quantum Nature of Particles

    CERN Document Server

    Salehi, H; Salehi, Hadi; Bisabr, Yousef

    2003-01-01

    We investigate a gravitational model whose vacuum sector is invariant under conformal transformations. In this model, matter is taken to be coupled with a metric which is different but conformally related to the metric appearing explicitly in the vacuum sector. It is then show that the effect of a conformal symmetry breaking would lead to a particle concept. In particular, a correspondence between quantum nature of the particles and the gravitational interaction of matter is established.

  9. Multiple conformations of proteins in native state

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Examples of protein sequences that can adopt multiple native states are recently accumulated. Characterization of the protein multiple conformations will have important implications for our understanding of the relationship between structure and function, and their folding kinetics. In present review, the experimental evidence for the existence of multiple conformations in the native state of proteins, the molecular basis and the biological significance of multiple conformations of proteins are focused.

  10. TASI Lectures on the Conformal Bootstrap

    CERN Document Server

    Simmons-Duffin, David

    2016-01-01

    These notes are from courses given at TASI and the Advanced Strings School in summer 2015. Starting from principles of quantum field theory and the assumption of a traceless stress tensor, we develop the basics of conformal field theory, including conformal Ward identities, radial quantization, reflection positivity, the operator product expansion, and conformal blocks. We end with an introduction to numerical bootstrap methods, focusing on the 2d and 3d Ising models.

  11. The center for plant and microbial complex carbohydrates at the University of Georgia Complex Carbohydrate Research Center. Annual report, September 15, 1990--December 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Albersheim, P.; Darvill, A.

    1991-08-01

    Research from the Complex Carbohydrates Research Center at the University of Georgia is presented. Topics include: Structural determination of soybean isoflavones which specifically induce Bradyrhizobium japonicum nodD1 but not the nodYABCSUIJ operon; structural analysis of the lipopolysaccharides (LPSs) from symbiotic mutants of Bradyrhizobium japonicum; structural characterization of lipooligosaccharides from Bradyrhizobium japonicum that are required for the specific nodulation of soybean; structural characterization of the LPSs from R. Leguminosarum biovar phaseoli, the symbiont of bean; characterization of bacteroid-specific LPS epitopes in R. leguminosarum biovar viciae; analysis of the surface polysaccharides of Rhizobium meliloti mutants whose lipopolysaccharides and extracellular polysaccharides can have the same function in symbiosis; characterization of a polysaccharide produced by certain Bradyrhizobium japonicum strains within soybean nodules; structural analysis of a streptococcal adhesin polysaccharide receptor; conformational studies of xyloglucan, the role of the fucosylated side chain in surface-specific cellulose-xyloglucan interactions; the structure of an acylated glucosamine oligosaccharide signal molecule (nod factor) involved in the symbiosis of Rhizobium leguminosarum biovar viciae with its host Vicia sativa; investigating membrane responses induced by oligogalacturonides in cultured cells; the polygalacturonase inhibitor protein; characterization of the self-incompatability glycoproteins from Petunia hybrida; investigation of the cell wall polysaccharide structures of Arabidopsis thaliana; and the glucan inhibition of virus infection of tabacco.

  12. Carbohydrate Supplementation Influences Serum Cytokines after Exercise under Hypoxic Conditions

    Directory of Open Access Journals (Sweden)

    Aline Venticinque Caris

    2016-11-01

    Full Text Available Introduction: Exercise performed at the hypoxia equivalent of an altitude of 4200 m is associated with elevated inflammatory mediators and changes in the Th1/Th2 response. By contrast, supplementation with carbohydrates has an anti-inflammatory effect when exercise is performed under normoxic conditions. The objective of this study was to evaluate the effect of carbohydrate supplementation on cytokines and cellular damage markers after exercise under hypoxic conditions at a simulated altitude of 4200 m. Methods: Seven adult male volunteers who exercised for 60 min at an intensity of 50% VO2Peak were randomly evaluated under three distinct conditions; normoxia, hypoxia and hypoxia + carbohydrate supplementation. Blood samples were collected at rest, at the end of exercise and after 60 min of recovery. To evaluate hypoxia + carbohydrate supplementation, volunteers received a solution of 6% carbohydrate (maltodextrin or a placebo (strawberry-flavored Crystal Light®; Kraft Foods, Northfield, IL, USA every 20 min during exercise and recovery. Statistical analyses comprised analysis of variance, with a one-way ANOVA followed by the Tukey post hoc test with a significance level of p < 0.05. Results: Under normoxic and hypoxic conditions, there was a significant increase in the concentration of IL-6 after exercise and after recovery compared to at rest (p < 0.05, while in the hypoxia + carbohydrate group, there was a significant increase in the concentration of IL-6 and TNF-α after exercise compared to at rest (p < 0.05. Furthermore, under this condition, TNF-α, IL-2 and the balance of IL-2/IL-4 were increased after recovery compared to at rest (p < 0.05. Conclusion: We conclude that carbohydrate supplementation modified the IL-6 and TNF-α serum concentrations and shifted the IL-2/IL-4 balance towards Th1 in response without glycemic, glutaminemia and cell damage effects.

  13. Conformal invariance conserved quantity of Hamilton systems

    Institute of Scientific and Technical Information of China (English)

    Cai Jian-Le; Luo Shao-Kai; Mei Feng-Xiang

    2008-01-01

    This paper studies conformal invariance and comserved quantRies of Hamilton system.The definition and the determining equation of conformal invariance for Hamilton system are provided.The relationship between the conformal invariance and the Lie symmetry are discussed,and the necessary and sufficient condition that the conformal invariance would be the Lie symmetry of the system under the infinitesimal one-parameter transformation group is deduced.It gives the conserved quantities of the system and an example for illustration.

  14. Conformal Anomaly and Large Scale Gravitational Coupling

    CERN Document Server

    Salehi, H

    2000-01-01

    We present a model in which the breackdown of conformal symmetry of a quantum stress-tensor due to the trace anomaly is related to a cosmological effect in a gravitational model. This is done by characterizing the traceless part of the quantum stress-tensor in terms of the stress-tensor of a conformal invariant classical scalar field. We introduce a conformal frame in which the anomalous trace is identified with a cosmological constant. In this conformal frame we establish the Einstein field equations by connecting the quantum stress-tensor with the large scale distribution of matter in the universe.

  15. Conformal and projective symmetries in Newtonian cosmology

    CERN Document Server

    Duval, Christian; Horvathy, Peter

    2016-01-01

    Definitions of non-relativistic conformal transformations are considered both in the Newton-Cartan and in the Kaluza-Klein-type Eisenhart/Bargmann geometrical frameworks. The symmetry groups that come into play are exemplified by the cosmological, and also the Newton-Hooke solutions of Newton's gravitational field equations. It is shown, in particular, that the maximal symmetry group of the standard cosmological model is isomorphic to the 13-dimensional conformal-Newton-Cartan group whose conformal-Bargmann extension is explicitly worked out. Attention is drawn to the appearance of independent space and time dilations, it contrast with the Schr{\\"o}dinger group or the Conformal Galilei Algebra.

  16. Rotational Spectroscopy Unveils Eleven Conformers of Adrenaline

    Science.gov (United States)

    Cabezas, C.; Cortijo, V.; Mata, S.; Lopez, J. C.; Alonso, J. L.

    2013-06-01

    Recent improvements in our LA-MB-FTMW instrumentation have allowed the characterization of eleven and eight conformers for the neurotransmitters adrenaline and noradrenaline respectively. The observation of this rich conformational behavior is in accordance with the recent observation of seven conformers for dopamine and in sharp contrast with the conformational reduction proposed for catecholamines. C. Cabezas, I. Peña, J. C. López, J. L. Alonso J. Phys. Chem. Lett. 2013, 4, 486. H. Mitsuda, M. Miyazaki, I. B. Nielsen, P. Carcabal,C. Dedonder, C. Jouvet, S. Ishiuchi, M. Fujii J. Phys. Chem. Lett. 2010, 1, 1130.

  17. Conformable eddy current array delivery

    Science.gov (United States)

    Summan, Rahul; Pierce, Gareth; Macleod, Charles; Mineo, Carmelo; Riise, Jonathan; Morozov, Maxim; Dobie, Gordon; Bolton, Gary; Raude, Angélique; Dalpé, Colombe; Braumann, Johannes

    2016-02-01

    The external surface of stainless steel containers used for the interim storage of nuclear material may be subject to Atmospherically Induced Stress Corrosion Cracking (AISCC). The inspection of such containers poses a significant challenge due to the large quantities involved; therefore, automating the inspection process is of considerable interest. This paper reports upon a proof-of-concept project concerning the automated NDT of a set of test containers containing artificially generated AISCCs. An Eddy current array probe with a conformable padded surface from Eddyfi was used as the NDT sensor and end effector on a KUKA KR5 arc HW robot. A kinematically valid cylindrical raster scan path was designed using the KUKA|PRC path planning software. Custom software was then written to interface measurement acquisition from the Eddyfi hardware with the motion control of the robot. Preliminary results and analysis are presented from scanning two canisters.

  18. Electromagnetic characterization of conformal antennas

    Science.gov (United States)

    Volakis, John L.; Kempel, Leo C.; Alexanian, Angelos; Jin, J. M.; Yu, C. L.; Woo, Alex C.

    1992-01-01

    The ultimate objective of this project is to develop a new technique which permits an accurate simulation of microstrip patch antennas or arrays with various feed, superstrate and/or substrate configurations residing in a recessed cavity whose aperture is planar, cylindrical or otherwise conformed to the substructure. The technique combines the finite element and boundary integral methods to formulate a system suitable for solution via the conjugate gradient method in conjunction with the fast Fourier transform. The final code is intended to compute both scattering and radiation patterns of the structure with an affordable memory demand. With upgraded capabilities, the four included papers examined the radar cross section (RCS), input impedance, gain, and resonant frequency of several rectangular configurations using different loading and substrate/superstrate configurations.

  19. A conformal model of gravitons

    CERN Document Server

    Donoghue, John F

    2016-01-01

    In the description of general covariance, the vierbein and the Lorentz connection can be treated as independent fundamental fields. With the usual gauge Lagrangian, the Lorentz connection is characterized by an asymptotically free running coupling. When running from high energy, the coupling gets large at a scale which can be called the Planck mass. If the Lorentz connection is confined at that scale, the low energy theory can have the Einstein Lagrangian induced at low energy through dimensional transmutation. However, in general there will be new divergences in such a theory and the Lagrangian basis should be expanded. I construct a conformally invariant model with a larger basis size which potentially may have the same property.

  20. Gravitomagnetic effects in conformal gravity

    CERN Document Server

    Said, Jackson Levi; Adami, Kristian Zarb

    2014-01-01

    Gravitomagnetic effects are characterized by two phenomena: first, the geodetic effect which describes the precession of the spin of a gyroscope in a free orbit around a massive object, second, the Lense-Thirring effect which describes the precession of the orbital plane about a rotating source mass. We calculate both these effects in the fourth-order theory of conformal Weyl gravity for the test case of circular orbits. We show that for the geodetic effect a linear term arises which may be interesting for high radial orbits, whereas for the Lense-Thirring effect the additional term has a diminishing effect for most orbits. Circular orbits are also considered in general leading up to a generalization of Kepler's third law.

  1. Approaching Conformality with Ten Flavors

    Energy Technology Data Exchange (ETDEWEB)

    Appelquist, Thomas; Brower, Richard C.; Buchoff, Michael I.; Cheng, Michael; Cohen, Saul D.; Fleming, George T.; Kiskis, Joe; Lin, Meifeng; Na, Heechang; Neil, Ethan T.; Osborn, James C.

    2012-04-01

    We present first results for lattice simulations, on a single volume, of the low-lying spectrum of an SU(3) Yang-Mills gauge theory with N{sub f} = 10 light fermions in the fundamental representation. Fits to the fermion mass dependence of various observables are found to be globally consistent with the hypothesis that this theory is within or just outside the strongly-coupled edge of the conformal window, with mass anomalous dimension {gamma}* {approx} 1 over the range of scales simulated. We stress that we cannot rule out the possibility of spontaneous chiral-symmetry breaking at scales well below our infrared cutoff. We discuss important systematic effects, including finite-volume corrections, and consider directions for future improvement.

  2. Approaching Conformality with Ten Flavors

    CERN Document Server

    Appelquist, Thomas; Buchoff, Michael I; Cheng, Michael; Cohen, Saul D; Fleming, George T; Kiskis, Joe; Lin, Meifeng; Na, Heechang; Neil, Ethan T; Osborn, James C; Rebbi, Claudio; Schaich, David; Schroeder, Chris; Voronov, Gennady; Vranas, Pavlos

    2012-01-01

    We present first results for lattice simulations, on a single volume, of the low-lying spectrum of an SU(3) Yang-Mills gauge theory with ten light fermions in the fundamental representation. Fits to the fermion mass dependence of various observables are found to be globally consistent with the hypothesis that this theory is within or just outside the strongly-coupled edge of the conformal window, with mass anomalous dimension approximately equal to 1 over the range of scales simulated. We stress that we cannot rule out the possibility of spontaneous chiral-symmetry breaking at scales well below our infrared cutoff. We discuss important systematic effects, including finite-volume corrections, and consider directions for future improvement.

  3. Predicting water-soluble carbohydrates and ethanol-soluble carbohydrates in cool-season grasses with near-infrared reflectance spectroscopy

    Science.gov (United States)

    Grazing animals may require a high or low total nonstructural carbohydrate diet for optimal health and production. Understanding how nonstructural carbohydrates fluctuate in Kentucky pastures and being able to quantify and monitor nonstructural carbohydrates in a timely manner will greatly aid in m...

  4. Selectivity switch in the catalytic functionalization of nonprotected carbohydrates: selective synthesis in the presence of anomeric and structurally similar carbohydrates under mild conditions.

    Science.gov (United States)

    Muramatsu, Wataru; Takemoto, Yuki

    2013-03-15

    A catalytic process for the chemo- and regioselective functionalization of nonprotected carbohydrates has been developed. This novel process allows selective thiocarbonylation, acylation, and sulfonylation of a particular hydroxy group in a particular carbohydrate in the simultaneous presence of structurally similar carbohydrates such as anomers. In addition, the chemoselectivity can be switched by regulating only the length of the alkyl chain in the organotin catalyst.

  5. Pharmaceutical, cosmeceutical, and traditional applications of marine carbohydrates.

    Science.gov (United States)

    Ahmed, Abdul Bakrudeen Ali; Adel, Mohaddeseh; Karimi, Pegah; Peidayesh, Mahvash

    2014-01-01

    Marine carbohydrates are most important organic molecules made by photosynthetic organisms. It is very essential for humankind: the role in being an energy source for the organism and they are considered as an important dissolve organic compound (DOC) in marine environment's sediments. Carbohydrates found in different marine environments in different concentrations. Polysaccharides of carbohydrates play an important role in various fields such as pharmaceutical, food production, cosmeceutical, and so on. Marine organisms are good resources of nutrients, and they are rich carbohydrate in sulfated polysaccharide. Seaweeds (marine microalgae) are used in different pharmaceutical industries, especially in pharmaceutical compound production. Seaweeds have a significant amount of sulfated polysaccharides, which are used in cosmeceutical industry, besides based on the biological applications. Since then, traditional people, cosmetics products, and pharmaceutical applications consider many types of seaweed as an important organism used in food process. Sulfated polysaccharides containing seaweed have potential uses in the blood coagulation system, antiviral activity, antioxidant activity, anticancer activity, immunomodulating activity, antilipidepic activity, etc. Some species of marine organisms are rich in polysaccharides such as sulfated galactans. Various polysaccharides such as agar and alginates, which are extracted from marine organisms, have several applications in food production and cosmeceutical industries. Due to their high health benefits, compound-derived extracts of marine polysaccharides have various applications and traditional people were using them since long time ago. In the future, much attention is supposed to be paid to unraveling the structural, compositional, and sequential properties of marine carbohydrate as well.

  6. GlycoCT-a unifying sequence format for carbohydrates.

    Science.gov (United States)

    Herget, S; Ranzinger, R; Maass, K; Lieth, C-W V D

    2008-08-11

    As part of the EUROCarbDB project (www.eurocarbdb.org) we have carefully analyzed the encoding capabilities of all existing carbohydrate sequence formats and the content of publically available structure databases. We have found that none of the existing structural encoding schemata are capable of coping with the full complexity to be expected for experimentally derived structural carbohydrate sequence data across all taxonomic sources. This gap motivated us to define an encoding scheme for complex carbohydrates, named GlycoCT, to overcome the current limitations. This new format is based on a connection table approach, instead of a linear encoding scheme, to describe the carbohydrate sequences, with a controlled vocabulary to name monosaccharides, adopting IUPAC rules to generate a consistent, machine-readable nomenclature. The format uses a block concept to describe frequently occurring special features of carbohydrate sequences like repeating units. It exists in two variants, a condensed form and a more verbose XML syntax. Sorting rules assure the uniqueness of the condensed form, thus making it suitable as a direct primary key for database applications, which rely on unique identifiers. GlycoCT encompasses the capabilities of the heterogeneous landscape of digital encoding schemata in glycomics and is thus a step forward on the way to a unified and broadly accepted sequence format in glycobioinformatics.

  7. Phosphorous Nutritional Level, Carbohydrate Reserves and Flower Quality in Olives

    Science.gov (United States)

    Erel, Ran; Yermiyahu, Uri; Yasuor, Hagai; Cohen Chamus, Dan; Schwartz, Amnon; Ben-Gal, Alon; Dag, Arnon

    2016-01-01

    The olive tree is generally characterized by relatively low final fruit set consequential to a significant rate of undeveloped pistils, pistil abortion, and flower and fruitlet abscission. These processes are acknowledged to be governed by competition for resources between the developing vegetative and reproductive organs. To study the role of phosphorus (P) nutritional level on reproductive development, trees were grown under four levels of P for three years in large containers. Phosphorus nutritional level was positively related to rate of reproductive bud break, inflorescence weight, rate of hermaphrodite flowers, pistil weight, fruitlet persistence, fruit set and the consequential total number of fruits. The positive impact of P nutrition on the productivity parameters was not related to carbohydrate reserves or to carbohydrate transport to the developing inflorescence. Phosphorous deficient trees showed significant impairment of assimilation rate, and yet, carbohydrates were accumulated in inflorescences at levels comparable to or higher than trees receiving high P. In contrast to female reproductive organs, pollen viability was consistently higher in P deficient trees, possibly due to the enhanced carbohydrate availability. Overall, the positive effect of P on female reproductive development was found to be independent of the total carbohydrate availability. Hence, P is speculated to have a direct influence on reproductive processes. PMID:27907133

  8. Interaction of carbohydrates with alcohol dehydrogenase: Effect on enzyme activity.

    Science.gov (United States)

    Jadhav, Swati B; Bankar, Sandip B; Granström, Tom; Ojamo, Heikki; Singhal, Rekha S; Survase, Shrikant A

    2015-09-01

    Alcohol dehydrogenase was covalently conjugated with three different oxidized carbohydrates i.e., glucose, starch and pectin. All the carbohydrates inhibited the enzyme. The inhibition was studied with respect to the inhibition rate constant, involvement of thiol groups in the binding, and structural changes in the enzyme. The enzyme activity decreased to half of its original activity at the concentration of 2 mg/mL of pectin, 4 mg/mL of glucose and 10 mg/mL of starch within 10 min at pH 7. This study showed oxidized pectin to be a potent inhibitor of alcohol dehydrogenase followed by glucose and starch. Along with the aldehyde-amino group interaction, thiol groups were also involved in the binding between alcohol dehydrogenase and carbohydrates. The structural changes occurring on binding of alcohol dehydrogenase with oxidized carbohydrates was also confirmed by fluorescence spectrophotometry. Oxidized carbohydrates could thus be used as potential inhibitors of alcohol dehydrogenase.

  9. In vivo and in vitro pollen maturation in Lilium: influence of carbohydrates

    Directory of Open Access Journals (Sweden)

    Christophe Clement

    2014-01-01

    Full Text Available The purpose of this study was to develop a protocol for in vitro conform pollen maturation, as a model to study the involvement of carbohydrates on pollen maturation in Lilium. In vivo and in vitro pollen maturations were followed and compared by transmission electron microscopy, and several in vitro parameters were tested in terms of carbohydrate physiology. In vivo, pollen maturation was initiated at the vacuolated microspore stage, and consisted of two successive phases. The first phase was characterized by reactivation of microspore organelles, followed by microspore mitosis, starch synthesis and vacuole breakdown. During the second phase, starch was progressively degraded whereas lipid and phytine reserves accumulated. In vivo, pollen maturation occured within 14 days and pollen germination rate was 73.6 ± 2.2%. We then attempted to realise in vitro pollen maturation starting from the vacuolated microspore stage. The best results were obtained with flower buds cultivated at 26oC, in 100 µmol/m2/s light, with a 16h/8h photoperiod on a modified Heller's medium supplemented with NAA (10-2 mg/l and sucrose (M/6. In these conditions, pollen maturation occured within 7 days only. In vitro matured pollen is cytologically comparable to in vivo developed pollen grains and the germination rate was 72.4 ± 3.7%. When flower buds were cultivated in the dark, the germination rate decreased, but this could be compensated by providing high sucrose concentrations (1M in the medium. Further, photosynthesis inhibitors had the same effect on pollen maturation than the darkness, strongly suggesting that photosynthesis occurs in the flower bud and is important for pollen maturation in Lilium.

  10. Conformal Higgs, or techni-dilaton- composite Higgs near conformality

    CERN Document Server

    Yamawaki, Koichi

    2010-01-01

    In contrast to the folklore that Technicolor (TC) is a "Higgsless theory", we shall discuss existence of a composite Higgs boson, Techni-Dilaton (TD), a pseudo-Nambu-Goldstone boson of the scale invariance in the Scale-invariant/Walking/Conformal TC (SWC TC) which generates a large anomalous dimension $\\gamma_m \\simeq 1$ in a wide region from the dynamical mass $m$ $= {\\cal O}$ (TeV) of the techni-fermion all the way up to the intrinsic scale $\\Lambda_{\\rm TC}$ of the SWC TC (analogue of $\\Lambda_{\\rm QCD}$), where $\\Lambda_{\\rm TC} $ is taken typically as the scale of the Extended TC scale $\\Lambda_{\\rm ETC}$: $\\Lambda_{\\rm TC} \\simeq \\Lambda_{\\rm ETC}\\sim10^3$ TeV $ (\\gg m)$. All the techni-hadrons have mass on the same order ${\\cal O} (m)$, which in SWC TC is extremely smaller than the intrinsic scale $\\Lambda_{\\rm TC} \\simeq \\Lambda_{\\rm ETC} $, in sharp contrast to QCD where both are of the same order. The mass of TD arises from the {\\it non-perturbative scale anomaly} associated with the techni-fermion ...

  11. Solution conformation and flexibility of capsular polysaccharides from Neisseria meningitidis and glycoconjugates with the tetanus toxoid protein

    Science.gov (United States)

    Abdelhameed, Ali Saber; Morris, Gordon A.; Almutairi, Fahad; Adams, Gary G.; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E.

    2016-10-01

    The structural integrity of meningococcal native, micro-fluidized and activated capsular polysaccharides and their glycoconjugates – in the form most relevant to their potential use as vaccines (dilute solution) - have been investigated with respect to their homogeneity, conformation and flexibility. Sedimentation velocity analysis showed that the polysaccharide size distributions were generally bimodal with some evidence for higher molar mass forms at higher concentration. Weight average molar masses Mw where lower for activated polysaccharides. Conjugation with tetanus toxoid protein however greatly increased the molar mass and polydispersity of the final conjugates. Glycoconjugates had an approximately unimodal log-normal but broad and large molar mass profiles, confirmed by sedimentation equilibrium “SEDFIT MSTAR” analysis. Conformation analysis using HYDFIT (which globally combines sedimentation and viscosity data), “Conformation Zoning” and Wales-van Holde approaches showed a high degree of flexibility – at least as great as the unconjugated polysaccharides, and very different from the tetanus toxoid (TT) protein used for the conjugation. As with the recently published finding for Hib-TT complexes, it is the carbohydrate component that dictates the solution behaviour of these glycoconjugates, although the lower intrinsic viscosities suggest some degree of compaction of the carbohydrate chains around the protein.

  12. Asymptotic symmetry algebra of conformal gravity

    CERN Document Server

    Irakleidou, M

    2016-01-01

    We compute asymptotic symmetry algebras of conformal gravity. Due to more general boundary conditions allowed in conformal gravity in comparison to those in Einstein gravity, we can classify the corresponding algebras. The highest algebra for non-trivial boundary conditions is five dimensional and it leads to global geon solution with non-vanishing charges.

  13. An extension theorem for conformal gauge singularities

    CERN Document Server

    Tod, Paul

    2007-01-01

    We analyse conformal gauge, or isotropic, singularities in cosmological models in general relativity. Using the calculus of tractors, we find conditions in terms of tractor curvature for a local extension of the conformal structure through a cosmological singularity and prove a local extension theorem.

  14. 14 CFR 17.45 - Conforming amendments.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Conforming amendments. 17.45 Section 17.45 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION PROCEDURAL RULES PROCEDURES FOR PROTESTS AND CONTRACTS DISPUTES Finality and Review § 17.45 Conforming amendments. The...

  15. 40 CFR 52.138 - Conformity procedures.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Conformity procedures. 52.138 Section...) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Arizona § 52.138 Conformity procedures. (a) Purpose. The... plans for metropolitan transportation planning organizations (MPOs) to use when determining...

  16. DIMENSIONS FOR RANDOM SELF-CONFORMAL SETS

    Institute of Scientific and Technical Information of China (English)

    Liu Yanyan; Wu Jun

    2003-01-01

    A set is called regular if its Hausdorff dimension and upper box-counting dimension coincide.In this paper,we prove that the random self-conformal set is regular almost surely.Also we determine the dimensions for a class of random self-conformal sets.

  17. Regular conformal system for Einstein equations

    Energy Technology Data Exchange (ETDEWEB)

    Choquet-Bruhat, Y.; Novello, M.

    1987-06-21

    We give a system of partial differential equations satisfied by a metric g conformal to an Einstein metric and by the conformal factor ..omega.., regular system in the sense that it does not contain negative powers of ..omega... We use the ideas of Friedrich but we obtain here a hyperbolic system in the sense of Leray, by a different method.

  18. The conformal approach to asymptotic analysis

    CERN Document Server

    Nicolas, Jean-Philippe

    2015-01-01

    This essay was written as an extended version of a talk given at a conference in Strasbourg on "Riemann, Einstein and geometry", organized by Athanase Papadopoulos in September 2014. Its aim is to present Roger Penrose's approach to asymptotic analysis in general relativity, which is based on conformal geometric techniques, focusing on historical and recent aspects of two specialized topics~: conformal scattering and peeling.

  19. Conformity to Peer Pressure in Preschool Children

    Science.gov (United States)

    Haun, Daniel B. M.; Tomasello, Michael

    2011-01-01

    Both adults and adolescents often conform their behavior and opinions to peer groups, even when they themselves know better. The current study investigated this phenomenon in 24 groups of 4 children between 4;2 and 4;9 years of age. Children often made their judgments conform to those of 3 peers, who had made obviously erroneous but unanimous…

  20. Separation of carbohydrates using hydrophilic interaction liquid chromatography.

    Science.gov (United States)

    Fu, Qing; Liang, Tu; Li, Zhenyu; Xu, Xiaoyong; Ke, Yanxiong; Jin, Yu; Liang, Xinmiao

    2013-09-20

    A strategy was developed to rapidly evaluate chromatographic properties of hydrophilic interaction chromatography (HILIC) columns for separating carbohydrates. Seven HILIC columns (Silica, Diol, TSK Amide-80, XAmide, Click Maltose, Click β-CD, and Click TE-Cys columns) were evaluated by using three monosaccharide and seven disaccharides as probes. The influence of column temperature on the peak shape and tautomerization of carbohydrates, as well as column selectivity were investigated. The influence of surface charge property on the retention was also studied by using glucose, glucuronic acid, and glucosamine, which indicated that buffer salt concentration and pH value in mobile phase was necessary to control the ionic interactions between ionic carbohydrates and HILIC columns. According to evaluation results, the XAmide column was selected as an example to establish experimental schemes for separation of complex mixtures of oligosaccharide.

  1. Dietary carbohydrate restriction as the first approach in diabetes management

    DEFF Research Database (Denmark)

    Feinman, Richard D; Pogozelski, Wendy K; Astrup, Arne;

    2015-01-01

    , in combination with the continued success of low-carbohydrate diets in the treatment of diabetes and metabolic syndrome without significant side effects, point to the need for a reappraisal of dietary guidelines. The benefits of carbohydrate restriction in diabetes are immediate and well documented. Concerns...... side effects comparable with those seen in many drugs. Here we present 12 points of evidence supporting the use of low-carbohydrate diets as the first approach to treating type 2 diabetes and as the most effective adjunct to pharmacology in type 1. They represent the best-documented, least......The inability of current recommendations to control the epidemic of diabetes, the specific failure of the prevailing low-fat diets to improve obesity, cardiovascular risk, or general health and the persistent reports of some serious side effects of commonly prescribed diabetic medications...

  2. The role of carbohydrate in dietary prescription for weight loss

    DEFF Research Database (Denmark)

    Astrup, Arne

    to be shown whether a low-glycemic index diet provides benefits beyond this. Low-carbohydrate diets may be an option for inducing weight loss in obese patients, but a very low intake of carbohydrate-rich foods is not commensurate with a healthy and palatable diet in the long term. However, there is evidence......The optimal diet for prevention of weight gain, obesity, metabolic syndrome, and type 2 diabetes is fat-reduced, fibre-rich, high in lowenergy density carbohydrates (fruit, vegetables, and whole grain products), and intake of energy-containing drinks is restricted. The reduction of the total fat...... content of ad libitum diets produces weight loss in both the short-term and over periods as long as 7 years. A fat-reduced diet, combined with physical activity, reduces all risk factors for cardiovascular disease, and reduces the incidence of type 2 diabetes. The combination of reduction of dietary fat...

  3. Structure-property relationships and biocompatibility of carbohydrate crosslinked polyurethanes.

    Science.gov (United States)

    Solanki, Archana; Mehta, Jayen; Thakore, Sonal

    2014-09-22

    Biocompatible and biodegradable polyurethanes (PUs) based on castor oil and polypropylene glycols (PPGs) were prepared using various carbohydrate crosslinkers: monosaccharide (glucose), disaccharide (sucrose) and polysaccharides (starch and cellulose). The mechanical and thermal properties were investigated and interpreted on the basis of SEM study. The advantage of incorporating various carbohydrates is to have tunable mechanical properties and biodegradability due to variety in their structure. The glass transition temperature and sorption behavior were dominated by the type of polyol than by the type of crosslinker. All the PUs were observed to be biodegradable as well as non-cytotoxic as revealed by MTT assay in normal lung cell line L132. The study supports the suitability of carbohydrates as important components of biocompatible PUs for development of biomedical devices.

  4. Derivatization of carbohydrates for GC and GC-MS analyses.

    Science.gov (United States)

    Ruiz-Matute, A I; Hernández-Hernández, O; Rodríguez-Sánchez, S; Sanz, M L; Martínez-Castro, I

    2011-05-15

    GC and GC-MS are excellent techniques for the analysis of carbohydrates; nevertheless the preparation of adequate derivatives is necessary. The different functional groups that can be found and the diversity of samples require specific methods. This review aims to collect the most important methodologies currently used, either published as new procedures or as new applications, for the analysis of carbohydrates. A high diversity of compounds with diverse functionalities has been selected: neutral carbohydrates (saccharides and polyalcohols), sugar acids, amino and iminosugars, polysaccharides, glycosides, glycoconjugates, anhydrosugars, difructose anhydrides and products resulting of Maillard reaction (osuloses, Amadori compounds). Chiral analysis has also been considered, describing the use of diastereomers and derivatives to be eluted on chiral stationary phases.

  5. Food sources of carbohydrates in a European cohort of adults

    DEFF Research Database (Denmark)

    Wirfält, E.; McTaggart, A.; Pala, V.

    2002-01-01

    OBJECTIVE: To describe the average consumption of carbohydrate-providing food groups among study centres of the European Prospective Investigation into Cancer and Nutrition (EPIC). METHODS: Of the 27 redefined EPIC study centres, 19 contributed subjects of both genders and eight centres female...... participants only (men, women, after exclusion of subjects under 35 and over 74 years of age from the original 36 900 total). Dietary data were obtained using the 24-hour recall methodology using the EPIC-SOFT software. The major sources of dietary carbohydrate were identified, and 16 food groups were examined....... RESULTS: The 10 food groups contributing most carbohydrate were bread; fruit; milk and milk products; sweet buns, cakes and pies; potato; sugar and jam; pasta and rice; vegetables and legumes; crispbread; and fruit and vegetable juices. Consumption of fruits as well as vegetables and legumes was higher...

  6. Neoglycoproteins as carbohydrate antigens: synthesis, analysis, and polyclonal antibody response.

    Science.gov (United States)

    Kerékgyártó, Márta; Fekete, Anikó; Szurmai, Zoltán; Kerékgyártó, János; Takács, László; Kurucz, István; Guttman, András

    2013-08-01

    The analysis and polyclonal antibody response for newly synthesized maltose-BSA conjugate neoglycoproteins is described. In this first proof of concept study, a simple carbohydrate antigen, maltose, was linked to BSA by reductive amination. An aglycone spacer was utilized to conserve the intact annular maltose structure and to promote the accessibility of the carbohydrate immunogen hapten during immunization. The neoglycoproteins were investigated by CGE and the number of conjugated maltose residues was determined by MALDI-TOF MS. The neoglycoproteins were then evaluated by immunization of BALB/c mice and the polyclonal antibody response was tested by ELISA as evidence for the presence of sugar-containing epitope-specific antibodies. Selective antibody binding was demonstrated to the synthesized neoglycoproteins with different (low and high) glycosylation degrees suggesting the possible use of this approach to generate antibodies. Moreover, the polyclonal antibody response was not inhibited by maltose or other simple carbohydrates to confirm presence of the neoglycoprotein-specific antibodies.

  7. Dietary carbohydrate restriction as the first approach in diabetes management

    DEFF Research Database (Denmark)

    Feinman, Richard D; Pogozelski, Wendy K; Astrup, Arne;

    2015-01-01

    , in combination with the continued success of low-carbohydrate diets in the treatment of diabetes and metabolic syndrome without significant side effects, point to the need for a reappraisal of dietary guidelines. The benefits of carbohydrate restriction in diabetes are immediate and well documented. Concerns......The inability of current recommendations to control the epidemic of diabetes, the specific failure of the prevailing low-fat diets to improve obesity, cardiovascular risk, or general health and the persistent reports of some serious side effects of commonly prescribed diabetic medications...... side effects comparable with those seen in many drugs. Here we present 12 points of evidence supporting the use of low-carbohydrate diets as the first approach to treating type 2 diabetes and as the most effective adjunct to pharmacology in type 1. They represent the best-documented, least...

  8. Digestion kinetics of carbohydrate fractions of citrus by-products.

    Science.gov (United States)

    Lashkari, Saman; Taghizadeh, Akbar

    2015-01-01

    The present experiment was carried out to determine the digestion kinetics of carbohydrate fractions of citrus by-products. Grapefruit pulp (GP), lemon pulp (LE), lime pulp (LI) and orange pulp (OP) were the test feed. Digestion kinetic of whole citrus by-products and neutral detergent fiber (NDF) fraction and acid detergent fiber (ADF) fractions of citrus by-products were measured using the in vitro gas production technique. Fermentation kinetics of the neutral detergent soluble carbohydrates (NDSC) fraction and hemicelluloses were calculated using a curve subtraction. The fermentation rate of whole was the highest for the LE (p fractions. There was no significant difference among potential gas production (A) volumes of whole test feeds (p fractions of citrus by-products have high potential for degradability. It could also be concluded that carbohydrate fractions of citrus by-products have remarkable difference in digestion kinetics and digestive behavior.

  9. Microalgal carbohydrates: an overview of the factors influencing carbohydrates production, and of main bioconversion technologies for production of biofuels.

    Science.gov (United States)

    Markou, Giorgos; Angelidaki, Irini; Georgakakis, Dimitris

    2012-11-01

    Microalgal biomass seems to be a promising feedstock for biofuel generation. Microalgae have relative high photosynthetic efficiencies, high growth rates, and some species can thrive in brackish water or seawater and wastewater from the food- and agro-industrial sector. Today, the main interest in research is the cultivation of microalgae for lipids production to generate biodiesel. However, there are several other biological or thermochemical conversion technologies, in which microalgal biomass could be used as substrate. However, the high protein content or the low carbohydrate content of the majority of the microalgal species might be a constraint for their possible use in these technologies. Moreover, in the majority of biomass conversion technologies, carbohydrates are the main substrate for production of biofuels. Nevertheless, microalgae biomass composition could be manipulated by several cultivation techniques, such as nutrient starvation or other stressed environmental conditions, which cause the microalgae to accumulate carbohydrates. This paper attempts to give a general overview of techniques that can be used for increasing the microalgal biomass carbohydrate content. In addition, biomass conversion technologies, related to the conversion of carbohydrates into biofuels are discussed.

  10. Preparation of water-soluble glycoconjugated poly(acrylamide) for NMR analyses of carbohydrate-carbohydrate interactions

    Science.gov (United States)

    Xuan, Trinh Anh; Trung, Phan Nghia; Dinh, Bui Long; Yamaguchi, Takumi; Kato, Koichi

    2014-05-01

    Oligosaccharide chains of glycoconjugates are important biopolymers not only as carriers of information in cell-cell interactions but also as markers of cellular differentiation, aging, and malignant alteration. Molecular interactions where carbohydrates are involved are usually considered as weak interactions, so the study and evaluation of these interactions is still in its infancy. The evidences and studies of carbohydrate-carbohydrate interactions (CCI) will be confirming the importance of this mechanism for specific cell adhesion and communication. Their development will go hand in hand with the development of new and more sensitive techniques to study weak interactions. Recently, synthetic glycopolymers with functions similar to those of such natural carbohydrates and with specific pendant saccharide moieties were used as a solution for enhancement CCI when forming polyvalent interactions. Carbohydrates are ubiquitous components of cell wall membranes and occur as glycolipids, glycoproteins, proteoglycans, and capsular polysaccharides. As such they can participate in forefront intramolecular and intracellular events. Apart from their recognized roles in the physicochemical properties of glycolipids and glycoproteins. In this study, we designed trisaccharide monomers for free radical polymerization. Subsequently, the trisaccharide unit for chemical conjugation was synthesized from galactosamine in good yield. For further NMR analyses of CCI, glycopolymers composed of these sugar derivatives will be provided.

  11. A geodesic model in conformal superspace

    CERN Document Server

    Gomes, Henrique de A

    2016-01-01

    In this paper, I look for the most general geometrodynamical symmetries compatible with spatial relational principles. I argue that they lead either to a completely static Universe, or one embodying spatial conformal diffeomorphisms. Demanding locality for an action compatible with these principles severely limits its form, both for the gravitational part as well as all matter couplings. The simplest and most natural choice for pure gravity has two propagating physical degrees of freedom (and no refoliation-invariance). The system has a geometric interpretation as a geodesic model in infinite dimensional conformal superspace. Conformal superspace is a stratified manifold, with different strata corresponding to different isometry groups. Choosing space to be (homeomorphic to) $S^3$, conformal superspace has a preferred stratum with maximal stabilizer group. This stratum consists of a single point -- corresponding to the conformal geometry of the round 3-sphere. This is the most homogeneous non-degenerate geome...

  12. Finite Conformal Quantum Gravity and Nonsingular Spacetimes

    CERN Document Server

    Modesto, Leonardo

    2016-01-01

    We explicitly prove that a class of finite quantum gravitational theories (in odd as well as in even dimension) is actually a range of anomaly-free conformally invariant theories in the spontaneously broken phase of the conformal Weyl symmetry. At classical level we show how the Weyl conformal invariance is likely able to tame the spacetime singularities that plague not only Einstein gravity, but also local and weakly non-local higher derivative theories. This latter statement is rigorously proved by a singularity theorem that applies to a large class of weakly non-local theories. Following the seminal paper by Narlikar and Kembhavi, we provide an explicit construction of singularity-free black hole exact solutions conformally equivalent to the Schwarzschild metric. Furthermore, we show that the FRW cosmological solutions and the Belinski, Khalatnikov, Lifshitz (BKL) spacetimes, which exactly solve the classical equations of motion, are conformally equivalent to regular spacetimes. Finally, we prove that the ...

  13. Conformant Planning via Symbolic Model Checking

    CERN Document Server

    Cimatti, A; 10.1613/jair.774

    2011-01-01

    We tackle the problem of planning in nondeterministic domains, by presenting a new approach to conformant planning. Conformant planning is the problem of finding a sequence of actions that is guaranteed to achieve the goal despite the nondeterminism of the domain. Our approach is based on the representation of the planning domain as a finite state automaton. We use Symbolic Model Checking techniques, in particular Binary Decision Diagrams, to compactly represent and efficiently search the automaton. In this paper we make the following contributions. First, we present a general planning algorithm for conformant planning, which applies to fully nondeterministic domains, with uncertainty in the initial condition and in action effects. The algorithm is based on a breadth-first, backward search, and returns conformant plans of minimal length, if a solution to the planning problem exists, otherwise it terminates concluding that the problem admits no conformant solution. Second, we provide a symbolic representation ...

  14. On Combinatorial Expansions of Conformal Blocks

    CERN Document Server

    Marshakov, A; Morozov, A

    2009-01-01

    In a recent paper (arXiv:0906.3219) the representation of Nekrasov partition function in terms of nontrivial two-dimensional conformal field theory has been suggested. For non-vanishing value of the deformation parameter \\epsilon=\\epsilon_1+\\epsilon_2 the instanton partition function is identified with a conformal block of Liouville theory with the central charge c = 1+ 6\\epsilon^2/\\epsilon_1\\epsilon_2. If reversed, this observation means that the universal part of conformal blocks, which is the same for all two-dimensional conformal theories with non-degenerate Virasoro representations, possesses a non-trivial decomposition into sum over sets of the Young diagrams, different from the natural decomposition studied in conformal field theory. We provide some details about this intriguing new development in the simplest case of the four-point correlation functions.

  15. Solvent structure improves docking prediction in lectin-carbohydrate complexes.

    Science.gov (United States)

    Gauto, Diego F; Petruk, Ariel A; Modenutti, Carlos P; Blanco, Juan I; Di Lella, Santiago; Martí, Marcelo A

    2013-02-01

    Recognition and complex formation between proteins and carbohydrates is a key issue in many important biological processes. Determination of the three-dimensional structure of such complexes is thus most relevant, but particularly challenging because of their usually low binding affinity. In silico docking methods have a long-standing tradition in predicting protein-ligand complexes, and allow a potentially fast exploration of a number of possible protein-carbohydrate complex structures. However, determining which of these predicted complexes represents the correct structure is not always straightforward. In this work, we present a modification of the scoring function provided by AutoDock4, a widely used docking software, on the basis of analysis of the solvent structure adjacent to the protein surface, as derived from molecular dynamics simulations, that allows the definition and characterization of regions with higher water occupancy than the bulk solvent, called water sites. They mimic the interaction held between the carbohydrate -OH groups and the protein. We used this information for an improved docking method in relation to its capacity to correctly predict the protein-carbohydrate complexes for a number of tested proteins, whose ligands range in size from mono- to tetrasaccharide. Our results show that the presented method significantly improves the docking predictions. The resulting solvent-structure-biased docking protocol, therefore, appears as a powerful tool for the design and optimization of development of glycomimetic drugs, while providing new insights into protein-carbohydrate interactions. Moreover, the achieved improvement also underscores the relevance of the solvent structure to the protein carbohydrate recognition process.

  16. Digestible and indigestible carbohydrates: interactions with postprandial lipid metabolism.

    Science.gov (United States)

    Lairon, Denis; Play, Barbara; Jourdheuil-Rahmani, Dominique

    2007-04-01

    The balance between fats and carbohydrates in the human diet is still a matter of very active debate. Indeed, the processing of ordinary mixed meals involves complex processes within the lumen of the upper digestive tract for digestion, in the small intestine mucosa for absorption and resecretion, and in peripheral tissues and in the circulation for final handling. The purpose of this review is to focus on available knowledge on the interactions of digestible or indigestible carbohydrates with lipid and lipoprotein metabolism in the postprandial state. The observations made in humans after test meals are reported and interpreted in the light of recent findings on the cellular and molecular levels regarding possible interplays between carbohydrates and lipid moieties in some metabolic pathways. Digestible carbohydrates, especially readily digestible starches or fructose, have been shown to exacerbate and/or delay postprandial lipemia, whereas some fiber sources can lower it. While interactions between dietary fibers and the process of lipid digestion and absorption have been studied mainly in the last decades, recent studies have shown that dietary carbohydrate moieties (e.g., glucose) can stimulate the intestinal uptake of cholesterol and lipid resecretion. In addition to the well-known glucose/fructose transporters, a number of transport proteins have recently been involved in intestinal lipid processing, whose implications in such interactions are discussed. The potential importance of postprandial insulinemia in these processes is also evaluated in the light of recent findings. The interactions of carbohydrates and lipid moieties in the postprandial state may result from both acute and chronic effects, both at transcriptional and posttranscriptional levels.

  17. KINETICS OF DELIGNIFICATION AND CARBOHYDRATE DEGRADATION DURING OXYGEN BLEACHING

    Institute of Scientific and Technical Information of China (English)

    K. L Nguyen

    2004-01-01

    Carbohydrate degradation during oxygen bleaching is associated with cleavage reactions. It is apparent that the loss of the cellulose DP (degree ofpolymisation)is strongly affected by the extent of the delignification. A strong linear correlation can be established between the DP of cellulose chains and the residual lignin in the pulp. The Nuclear Growth concept and Percolation Theory for heterogenous system can be combined to formulate kinetic models for both the delignification and the degradation of carbohydrate. The models prediction is statistically robust and can be applied to different pulps at different bleaching conditions.

  18. Transgenic Mice Convert Carbohydrates to Essential Fatty Acids

    OpenAIRE

    Pai, Victor J.; Bin Wang; Xiangyong Li; Lin Wu; Kang, Jing X.

    2014-01-01

    Transgenic mice (named “Omega mice”) were engineered to carry both optimized fat-1 and fat-2 genes from the roundworm Caenorhabditis elegans and are capable of producing essential omega-6 and omega-3 fatty acids from saturated fats or carbohydrates. When maintained on a high-saturated fat diet lacking essential fatty acids or a high-carbohydrate, no-fat diet, the Omega mice exhibit high tissue levels of both omega-6 and omega-3 fatty acids, with a ratio of ∼1∶1. This study thus presents an in...

  19. Diagnosing and Treating Intolerance to Carbohydrates in Children

    Directory of Open Access Journals (Sweden)

    Roberto Berni Canani

    2016-03-01

    Full Text Available Intolerance to carbohydrates is relatively common in childhood, but still poorly recognized and managed. Over recent years it has come to the forefront because of progresses in our knowledge on the mechanisms and treatment of these conditions. Children with intolerance to carbohydrates often present with unexplained signs and symptoms. Here, we examine the most up-to-date research on these intolerances, discuss controversies relating to the diagnostic approach, including the role of molecular analysis, and provide new insights into modern management in the pediatric age, including the most recent evidence for correct dietary treatment.

  20. Importance of low carbohydrate diets in diabetes management

    Directory of Open Access Journals (Sweden)

    Hall RM

    2016-03-01

    Full Text Available Rosemary M Hall, Amber Parry Strong, Jeremy D KrebsCentre for Endocrine, Diabetes and Obesity Research, Capital and Coast District Health Board, Wellington, New Zealand Abstract: Dietary strategies are fundamental in the management of diabetes. Historically, strict dietary control with a low carbohydrate diet was the only treatment option. With increasingly effective medications, the importance of dietary change decreased. Recommendations focused on reducing dietary fat to prevent atherosclerotic disease, with decreasing emphasis on the amount and quality of carbohydrate. As the prevalence of obesity and diabetes escalates, attention has returned to the macronutrient composition of the diet. Very low carbohydrate diets (VLCD's have demonstrated effective initial weight loss and improvement in glycemic control, but difficult long-term acceptability and worsening lipid profile. Modifications to the very low carbohydrate (VLC have included limiting saturated fat and increasing carbohydrate (CHO and protein. Reducing saturated fat appears pivotal in reducing low-density lipoprotein (LDL cholesterol and may mitigate adverse effects of traditional VLCD's. Increased dietary protein enhances satiety, reduces energy intake, and improves glycemic homeostasis, but without sustained improvements in glycemic control or cardiovascular risk over and above the effect of weight loss. Additionally, recent studies in type 1 diabetes mellitus suggest promising benefits to diabetes control with low carbohydrate diets, without concerning effects on ketosis or hypoglycemia. Dietary patterns may highlight pertinent associations. For example, Mediterranean-style and paleolithic-type diets, low in fat and carbohydrate, are associated with reduced body weight and improved glycemic and cardiovascular outcomes in type 2 diabetes mellitus (T2DM. A feature of these dietary patterns is low refined CHO and sugar and higher fiber, and it is possible that increasing sugar

  1. Carbohydrate nanocarriers in biomedical applications: functionalization and construction.

    Science.gov (United States)

    Kang, Biao; Opatz, Till; Landfester, Katharina; Wurm, Frederik R

    2015-11-21

    The specific targeting of either tumor cells or immune cells in vivo by carefully designed and appropriately surface-functionalized nanocarriers may become an effective therapeutic treatment for a variety of diseases. Carbohydrates, which are prominent biomolecules, have shown their outstanding ability in balancing the biocompatibility, stability, biodegradability, and functionality of nanocarriers. The recent applications of sugar (mono/oligosaccharides and/or polysaccharides) for the development of nanomedicines are summarized in this review, including the application of carbohydrates for the surface-functionalization of various nanocarriers and for the construction of the nanocarrier itself. Current problems and challenges are also addressed.

  2. Permeable conformal walls and holography

    Science.gov (United States)

    Bachas, Constantin; de Boer, Jan; Dijkgraaf, Robbert; Ooguri, Hirosi

    2002-06-01

    We study conformal field theories in two dimensions separated by domain walls, which preserve at least one Virasoro algebra. We develop tools to study such domain walls, extending and clarifying the concept of `folding' discussed in the condensed-matter literature. We analyze the conditions for unbroken supersymmetry, and discuss the holographic duals in AdS3 when they exist. One of the interesting observables is the Casimir energy between a wall and an anti-wall. When these separate free scalar field theories with different target-space radii, the Casimir energy is given by the dilogarithm function of the reflection probability. The walls with holographic duals in AdS3 separate two sigma models, whose target spaces are moduli spaces of Yang-Mills instantons on T4 or K3. In the supergravity limit, the Casimir energy is computable as classical energy of a brane that connects the walls through AdS3. We compare this result with expectations from the sigma-model point of view.

  3. Permeable conformal walls and holography

    CERN Document Server

    Bachas, C P; Dijkgraaf, R; Ooguri, H

    2002-01-01

    We study conformal field theories in two dimensions separated by domain walls, which preserve at least one Virasoro algebra. We develop tools to study such domain walls, extending and clarifying the concept of `folding' discussed in the condensed-matter literature. We analyze the conditions for unbroken supersymmetry, and discuss the holographic duals in AdS3 when they exist. One of the interesting observables is the Casimir energy between a wall and an anti-wall. When these separate free scalar field theories with different target-space radii, the Casimir energy is given by the dilogarithm function of the reflection probability. The walls with holographic duals in AdS3 separate two sigma models, whose target spaces are moduli spaces of Yang-Mills instantons on T4 or K3. In the supergravity limit, the Casimir energy is computable as classical energy of a brane that connects the walls through AdS3. We compare this result with expectations from the sigma-model point of view.

  4. Conforming Morse-Smale Complexes.

    Science.gov (United States)

    Gyulassy, Attila; Günther, David; Levine, Joshua A; Tierny, Julien; Pascucci, Valerio

    2014-12-01

    Morse-Smale (MS) complexes have been gaining popularity as a tool for feature-driven data analysis and visualization. However, the quality of their geometric embedding and the sole dependence on the input scalar field data can limit their applicability when expressing application-dependent features. In this paper we introduce a new combinatorial technique to compute an MS complex that conforms to both an input scalar field and an additional, prior segmentation of the domain. The segmentation constrains the MS complex computation guaranteeing that boundaries in the segmentation are captured as separatrices of the MS complex. We demonstrate the utility and versatility of our approach with two applications. First, we use streamline integration to determine numerically computed basins/mountains and use the resulting segmentation as an input to our algorithm. This strategy enables the incorporation of prior flow path knowledge, effectively resulting in an MS complex that is as geometrically accurate as the employed numerical integration. Our second use case is motivated by the observation that often the data itself does not explicitly contain features known to be present by a domain expert. We introduce edit operations for MS complexes so that a user can directly modify their features while maintaining all the advantages of a robust topology-based representation.

  5. Cosmology in Conformally Flat Spacetime

    Science.gov (United States)

    Endean, Geoffrey

    1997-04-01

    A possible solution to cosmological age and redshift-distance difficulties has recently been proposed by applying the appropriate conformally flat spacetime (CFS) coordinates to the standard solution of the field equations in a standard dust model closed universe. Here it is shown that CFS time correctly measures the true age of the universe, thus answering a major theoretical objection to the proposal. It is also shown that the CFS interpretation leads to a strong Copernican principle and is in all other respects wholly self-consistent. The deceleration parameter q0 is related to t0, the present age of the universe divided by L, the scale length of its curvature (an absolute constant). The values of q0 and L are approximately 5/6 and 9.2 × 109 yr, respectively. It is shown that the universe started everywhere simultaneously, with no recession velocity until the effects of its closed topology became significant. Conclusions to the contrary in standard theory (the big bang) stem from a different definition of recession velocity. The theoretical present cosmological mass density is quantified as 4.4 × 10-27 kg m-3 approximately, thus greatly reducing, in a closed universe, the observational requirement to find hidden mass. It is also shown that the prediction of standard theory, for a closed universe, of collapse toward a big crunch termination, will not in fact take place.

  6. 47 CFR 2.1072 - Limitation on Declaration of Conformity.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Limitation on Declaration of Conformity. 2.1072... Conformity § 2.1072 Limitation on Declaration of Conformity. (a) The Declaration of Conformity signifies that...'s rules. (b) A Declaration of Conformity by the responsible party is effective until a...

  7. Representation of target-bound drugs by computed conformers: implications for conformational libraries

    Directory of Open Access Journals (Sweden)

    Goede Andrean

    2006-06-01

    Full Text Available Abstract Background The increasing number of known protein structures provides valuable information about pharmaceutical targets. Drug binding sites are identifiable and suitable lead compounds can be proposed. The flexibility of ligands is a critical point for the selection of potential drugs. Since computed 3D structures of millions of compounds are available, the knowledge of their binding conformations would be a great benefit for the development of efficient screening methods. Results Integration of two public databases allowed superposition of conformers for 193 approved drugs with 5507 crystallised target-bound counterparts. The generation of 9600 drug conformers using an atomic force field was carried out to obtain an optimal coverage of the conformational space. Bioactive conformations are best described by a conformational ensemble: half of all drugs exhibit multiple active states, distributed over the entire range of the reachable energy and conformational space. A number of up to 100 conformers per drug enabled us to reproduce the bound states within a similarity threshold of 1.0 Å in 70% of all cases. This fraction rises to about 90% for smaller or average sized drugs. Conclusion Single drugs adopt multiple bioactive conformations if they interact with different target proteins. Due to the structural diversity of binding sites they adopt conformations that are distributed over a broad conformational space and wide energy range. Since the majority of drugs is well represented by a predefined low number of conformers (up to 100 this procedure is a valuable method to compare compounds by three-dimensional features or for fast similarity searches starting with pharmacophores. The underlying 9600 generated drug conformers are downloadable from the Super Drug Web site 1. All superpositions are visualised at the same source. Additional conformers (110,000 of 2400 classified WHO-drugs are also available.

  8. Conformational elasticity theory of chain molecules

    Institute of Scientific and Technical Information of China (English)

    YANG; Xiaozhen

    2001-01-01

    This paper develops a conformational elasticity theory of chain molecules, which is based on three key points: (ⅰ) the molecular model is the rotational isomeric state (RIS) model; (ⅱ) the conformational distribution function of a chain molecule is described by a function of two variables, the end-to-end distance of a chain conformation and the energy of the conformation; (ⅲ) the rule of changes in the chain conformational states during deformation is that a number of chain conformations would vanish. The ideal deformation behavior calculated by the theory shows that the change in chain conformations is physically able to make the upward curvature of the stress-strain curve at the large-scale deformation of natural rubber. With the theory, different deformation behaviors between polymers with different chemical structures can be described, the energy term of the stress in the deformations can be predicted, and for natural rubber the fraction of the energy term is around 13%, coinciding with the experimental results.

  9. Dynamic Conformations of Nucleosome Arrays in Solution from Small-Angle X-ray Scattering

    Science.gov (United States)

    Howell, Steven C.

    Chromatin conformation and dynamics remains unsolved despite the critical role of the chromatin in fundamental genetic functions such as transcription, replication, and repair. At the molecular level, chromatin can be viewed as a linear array of nucleosomes, each consisting of 147 base pairs (bp) of double-stranded DNA (dsDNA) wrapped around a protein core and connected by 10 to 90 bp of linker dsDNA. Using small-angle X-ray scattering (SAXS), we investigated how the conformations of model nucleosome arrays in solution are modulated by ionic condition as well as the effect of linker histone proteins. To facilitate ensemble modeling of these SAXS measurements, we developed a simulation method that treats coarse-grained DNA as a Markov chain, then explores possible DNA conformations using Metropolis Monte Carlo (MC) sampling. This algorithm extends the functionality of SASSIE, a program used to model intrinsically disordered biological molecules, adding to the previous methods for simulating protein, carbohydrates, and single-stranded DNA. Our SAXS measurements of various nucleosome arrays together with the MC generated models provide valuable solution structure information identifying specific differences from the structure of crystallized arrays.

  10. Micro-Spectroscopic Imaging of Lignin-Carbohydrate Complexes in Plant Cell Walls and Their Migration During Biomass Pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Yining; Zhao, Shuai; Wei, Hui; Tucker, Melvin P.; Johnson, David K.; Himmel, Michael E.; Mosier, Nathan S.; Meilan, Richard; Ding, Shi-You

    2015-04-27

    In lignocellulosic biomass, lignin is the second most abundant biopolymer. In plant cell walls, lignin is associated with polysaccharides to form lignin-carbohydrate complexes (LCC). LCC have been considered to be a major factor that negatively affects the process of deconstructing biomass to simple sugars by cellulosic enzymes. Here, we report a micro-spectroscopic approach that combines fluorescence lifetime imaging microscopy and Stimulated Raman Scattering microscopy to probe in situ lignin concentration and conformation at each cell wall layer. This technique does not require extensive sample preparation or any external labels. Using poplar as a feedstock, for example, we observe variation of LCC in untreated tracheid poplar cell walls. The redistribution of LCC at tracheid poplar cell wall layers is also investigated when the chemical linkages between lignin and hemicellulose are cleaved during pretreatment. Our study would provide new insights into further improvement of the biomass pretreatment process.

  11. Conformation-dependent DNA attraction

    Science.gov (United States)

    Li, Weifeng; Nordenskiöld, Lars; Zhou, Ruhong; Mu, Yuguang

    2014-05-01

    Understanding how DNA molecules interact with other biomolecules is related to how they utilize their functions and is therefore critical for understanding their structure-function relationships. For a long time, the existence of Z-form DNA (a left-handed double helical version of DNA, instead of the common right-handed B-form) has puzzled the scientists, and the definitive biological significance of Z-DNA has not yet been clarified. In this study, the effects of DNA conformation in DNA-DNA interactions are explored by molecular dynamics simulations. Using umbrella sampling, we find that for both B- and Z-form DNA, surrounding Mg2+ ions always exert themselves to screen the Coulomb repulsion between DNA phosphates, resulting in very weak attractive force. On the contrary, a tight and stable bound state is discovered for Z-DNA in the presence of Mg2+ or Na+, benefiting from their hydrophobic nature. Based on the contact surface and a dewetting process analysis, a two-stage binding process of Z-DNA is outlined: two Z-DNA first attract each other through charge screening and Mg2+ bridges to phosphate groups in the same way as that of B-DNA, after which hydrophobic contacts of the deoxyribose groups are formed via a dewetting effect, resulting in stable attraction between two Z-DNA molecules. The highlighted hydrophobic nature of Z-DNA interaction from the current study may help to understand the biological functions of Z-DNA in gene transcription.Understanding how DNA molecules interact with other biomolecules is related to how they utilize their functions and is therefore critical for understanding their structure-function relationships. For a long time, the existence of Z-form DNA (a left-handed double helical version of DNA, instead of the common right-handed B-form) has puzzled the scientists, and the definitive biological significance of Z-DNA has not yet been clarified. In this study, the effects of DNA conformation in DNA-DNA interactions are explored by

  12. Spectra of conformal sigma models

    Energy Technology Data Exchange (ETDEWEB)

    Tlapak, Vaclav

    2015-04-15

    In this thesis the spectra of conformal sigma models defined on (generalized) symmetric spaces are analysed. The spaces where sigma models are conformal without the addition of a Wess-Zumino term are supermanifolds, in other words spaces that include fermionic directions. After a brief review of the general construction of vertex operators and the background field expansion, we compute the diagonal terms of the one-loop anomalous dimensions of sigma models on semi-symmetric spaces. We find that the results are formally identical to the symmetric case. However, unlike for sigma models on symmetric spaces, off diagonal terms that lead to operator mixing are also present. These are not computed here. We then present a detailed analysis of the one-loop spectrum of the supersphere S{sup 3} {sup vertical} {sup stroke} {sup 2} sigma model as one of the simplest examples. The analysis illustrates the power and simplicity of the construction. We use this data to revisit a duality with the OSP(4 vertical stroke 2) Gross-Neveu model that was proposed by Candu and Saleur. With the help of a recent all-loop result for the anomalous dimension of (1)/(2)BPS operators of Gross-Neveu models, we are able to recover the entire zero-mode spectrum of the supersphere model. We also argue that the sigma model constraints and its equations of motion are implemented correctly in the Gross-Neveu model, including the one-loop data. The duality is further supported by a new all-loop result for the anomalous dimension of the ground states of the sigma model. However, higher-gradient operators cannot be completely recovered. It is possible that this discrepancy is related to a known instability of the sigma model. The instability of sigma models is due to symmetry preserving high-gradient operators that become relevant at arbitrarily small values of the coupling. This feature has been observed long ago in one-loop calculations of the O(N)-vector model and soon been realized to be a generic

  13. Topological conformal defects with tensor networks

    Science.gov (United States)

    Hauru, Markus; Evenbly, Glen; Ho, Wen Wei; Gaiotto, Davide; Vidal, Guifre

    2016-09-01

    The critical two-dimensional classical Ising model on the square lattice has two topological conformal defects: the Z2 symmetry defect Dɛ and the Kramers-Wannier duality defect Dσ. These two defects implement antiperiodic boundary conditions and a more exotic form of twisted boundary conditions, respectively. On the torus, the partition function ZD of the critical Ising model in the presence of a topological conformal defect D is expressed in terms of the scaling dimensions Δα and conformal spins sα of a distinct set of primary fields (and their descendants, or conformal towers) of the Ising conformal field theory. This characteristic conformal data {Δα,sα}D can be extracted from the eigenvalue spectrum of a transfer matrix MD for the partition function ZD. In this paper, we investigate the use of tensor network techniques to both represent and coarse grain the partition functions ZDɛand ZD σ of the critical Ising model with either a symmetry defect Dɛ or a duality defect Dσ. We also explain how to coarse grain the corresponding transfer matrices MDɛand MD σ, from which we can extract accurate numerical estimates of {Δα,sα}Dɛ and {Δα,sα}Dσ. Two key ingredients of our approach are (i) coarse graining of the defect D , which applies to any (i.e., not just topological) conformal defect and yields a set of associated scaling dimensions Δα, and (ii) construction and coarse graining of a generalized translation operator using a local unitary transformation that moves the defect, which only exist for topological conformal defects and yields the corresponding conformal spins sα.

  14. Conformal dynamical equivalence and applications

    Science.gov (United States)

    Spyrou, N. K.

    2011-02-01

    The "Conformal Dynamical Equivalence" (CDE) approach is briefly reviewed, and some of its applications, at various astrophysical levels (Sun, Solar System, Stars, Galaxies, Clusters of Galaxies, Universe as a whole), are presented. According to the CDE approach, in both the Newtonian and general-relativistic theories of gravity, the isentropic hydrodynamic flows in the interior of a bounded gravitating perfect-fluid source are dynamically equivalent to geodesic motions in a virtual, fully defined fluid source. Equivalently, the equations of hydrodynamic motion in the former source are functionally similar to those of the geodesic motions in the latter, physically, fully defined source. The CDE approach is followed for the dynamical description of the motions in the fluid source. After an observational introduction, taking into account all the internal physical characteristics of the corresponding perfect-fluid source, and based on the property of the isentropic hydrodynamic flows (quite reasonable for an isolated physical system), we examine a number of issues, namely, (i) the classical Newtonian explanation of the celebrated Pioneer-Anomaly effect in the Solar System, (ii) the possibility of both the attractive gravity and the repulsive gravity in a non-quantum Newtonian framework, (iii) the evaluation of the masses - theoretical, dynamical, and missing - and of the linear dimensions of non-magnetized and magnetized large-scale cosmological structures, (iv) the explanation of the flat-rotation curves of disc galaxies, (v) possible formation mechanisms of winds and jets, and (vi) a brief presentation of a conventional approach - toy model to the dynamics of the Universe, characterized by the dominant collisional dark matter (with its subdominant luminous baryonic "contamination"), correctly interpreting the cosmological observational data without the need of the notions dark energy, cosmological constant, and universal accelerating expansion.

  15. Conformal invariance in quantum field theory

    CERN Document Server

    Todorov, Ivan T; Petkova, Valentina B

    1978-01-01

    The present volume is an extended and up-to-date version of two sets of lectures by the first author and it reviews more recent work. The notes aim to present a self-contained exposition of a constructive approach to conformal invariant quantum field theory. Other parts in application of the conformal group to quantum physics are only briefly mentioned. The relevant mathematical material (harmonic analysis on Euclidean conformal groups) is briefly summarized. A new exposition of physical applications is given, which includes an explicit construction of the vacuum operator product expansion for the free zero mass fields.

  16. The decomposition of global conformal invariants

    CERN Document Server

    Alexakis, Spyros

    2012-01-01

    This book addresses a basic question in differential geometry that was first considered by physicists Stanley Deser and Adam Schwimmer in 1993 in their study of conformal anomalies. The question concerns conformally invariant functionals on the space of Riemannian metrics over a given manifold. These functionals act on a metric by first constructing a Riemannian scalar out of it, and then integrating this scalar over the manifold. Suppose this integral remains invariant under conformal re-scalings of the underlying metric. What information can one then deduce about the Riemannian scalar? Dese

  17. Conformational and Vibrational Studies of Triclosan

    Science.gov (United States)

    Özişik, Haci; Bayari, S. Haman; Saǧlam, Semran

    2010-01-01

    The conformational equilibrium of triclosan (5-chloro-2-(2, 4-dichlorophenoxy) phenol) have been calculated using density functional theory (DFTe/B3LYP/6-311++G(d, p)) method. Four different geometries were found to correspond to energy minimum conformations. The IR spectrum of triclosan was measured in the 4000-400 cm-1 region. We calculated the harmonic frequencies and intensities of the most stable conformers in order to assist in the assignment of the vibrational bands in the experimental spectrum. The fundamental vibrational modes were characterized depending on their total energy distribution (TED%) using scaled quantum mechanical (SQM) force field method.

  18. Static validation of licence conformance policies

    DEFF Research Database (Denmark)

    Hansen, Rene Rydhof; Nielson, Flemming; Nielson, Hanne Riis

    2008-01-01

    Policy conformance is a security property gaining importance due to commercial interest like Digital Rights Management. It is well known that static analysis can be used to validate a number of more classical security policies, such as discretionary and mandatory access control policies, as well...... as communication protocols using symmetric and asymmetric cryptography. In this work we show how to develop a Flow Logic for validating the conformance of client software with respect to a licence conformance policy. Our approach is sufficiently flexible that it extends to fully open systems that can admit new...

  19. Conformal Gravity: Dark Matter and Dark Energy

    Directory of Open Access Journals (Sweden)

    Robert K. Nesbet

    2013-01-01

    Full Text Available This short review examines recent progress in understanding dark matter, dark energy, and galactic halos using theory that departs minimally from standard particle physics and cosmology. Strict conformal symmetry (local Weyl scaling covariance, postulated for all elementary massless fields, retains standard fermion and gauge boson theory but modifies Einstein–Hilbert general relativity and the Higgs scalar field model, with no new physical fields. Subgalactic phenomenology is retained. Without invoking dark matter, conformal gravity and a conformal Higgs model fit empirical data on galactic rotational velocities, galactic halos, and Hubble expansion including dark energy.

  20. Conformal field theory on the plane

    CERN Document Server

    Ribault, Sylvain

    2014-01-01

    We provide an introduction to conformal field theory on the plane in the conformal bootstrap approach. We introduce the main ideas of the bootstrap approach to quantum field theory, and how they apply to two-dimensional theories with local conformal symmetry. We describe the mathematical structures which appear in such theories, from the Virasoro algebra and its representations, to the BPZ equations and their solutions. As examples, we study a number of models: Liouville theory, (generalized) minimal models, free bosonic theories, the $H_3^+$ model, and the $SU_2$ and $\\widetilde{SL}_2(\\mathbb{R})$ WZW models.

  1. Willmore energy estimates in conformal Berger spheres

    Energy Technology Data Exchange (ETDEWEB)

    Barros, Manuel, E-mail: mbarros@ugr.es [Departamento de Geometria y Topologia, Facultad de Ciencias Universidad de Granada, 1807 Granada (Spain); Ferrandez, Angel, E-mail: aferr@um.es [Departamento de Matematicas, Universidad de Murcia Campus de Espinardo, 30100 Murcia (Spain)

    2011-07-15

    Highlights: > The Willmore energy is computed in a wide class of surfaces. > Isoperimetric inequalities for the Willmore energy of Hopf tori are obtained. > The best possible lower bound is achieved on isoareal Hopf tori. - Abstract: We obtain isoperimetric inequalities for the Willmore energy of Hopf tori in a wide class of conformal structures on the three sphere. This class includes, on the one hand, the family of conformal Berger spheres and, on the other hand, a one parameter family of Lorentzian conformal structures. This allows us to give the best possible lower bound of Willmore energies concerning isoareal Hopf tori.

  2. Conformable Fractional Nikiforov—Uvarov Method

    Science.gov (United States)

    Karayer, H.; Demirhan, D.; Büyükkılıç, F.

    2016-07-01

    We introduce conformable fractional Nikiforov—Uvarov (NU) method by means of conformable fractional derivative which is the most natural definition in non-integer calculus. Since, NU method gives exact eigenstate solutions of Schrödinger equation (SE) for certain potentials in quantum mechanics, this method is carried into the domain of fractional calculus to obtain the solutions of fractional SE. In order to demonstrate the applicability of the conformable fractional NU method, we solve fractional SE for harmonic oscillator potential, Woods—Saxon potential, and Hulthen potential.

  3. Conformal blocks in the QCD Pomeron formalism

    CERN Document Server

    Navelet, H

    1996-01-01

    The conformal invariance properties of the QCD Pomeron in the transverse plane allow us to give an explicit analytical expression for the conformal eigenvectors in the mixed representation in terms of two conformal blocks, each block being the product of an holomorphic times an antiholomorphic function. This property is used to give an exact expression for various functions of interest, the Pomeron amplitude in both momentum and impact-parameter variables, the QCD dipole multiplicities and dipole-dipole cross-sections in the whole parameter space, and we recover the expression of the four-point gluon Green function given recently by Lipatov

  4. QCD, conformal invariance and the two Pomerons

    CERN Document Server

    Munier, S

    1998-01-01

    Using the solution of the BFKL equation including the leading and subleading conformal spin components, we show how the conformal invariance underlying the leading log (1/x) expansion of perturbative QCD leads to elastic amplitudes described by two effective Pomeron singularities. One Pomeron is the well-known "hard" BFKL leading singularity while the new one appears from a shift of the higher conformal spin BFKL singularities from subleading to leading position. This new effective singularity is compatible with the "soft" Pomeron and thus, together with the "hard" Pomeron, meets at large $Q^{2}$ the "double Pomeron" solution which has been recently conjectured by Donnachie and Landshoff.

  5. Syntheses of Novel Highly Symmetric Carbohydrates Bearing Diacylhydrazine Framework

    Institute of Scientific and Technical Information of China (English)

    YANG Bo; ZHANG Shu-sheng; LI Hui-xiang; LI Ji-zhi; JIAO Kui

    2005-01-01

    Several novel highly symmetric carbohydrates bearing a diacylhydrazine framework have been synthesized via a five-step procedure by utilizing D-glucose, D-galactose and D-xylose as the starting materials, respectively. The target compounds have been characterized with IR, 1H NMR and elemental analysis.

  6. Science Study Aids 3: Carbohydrates - Nature's Energy Source.

    Science.gov (United States)

    McConnell, Bill

    This publication is the third of a series of seven supplementary investigative materials for use in secondary science classes providing up-to-date research-related investigations. This unit is structured for grade levels 7 through 12. It is concerned with the role of carbohydrates as important nutrients for consumers. This guide will enable…

  7. Horizontal transfer of carbohydrate metabolism genes into ectomycorrhizal Amanita

    NARCIS (Netherlands)

    Chaib De Mares, Maryam; Hess, Jaqueline; Floudas, Dimitrios; Lipzen, Anna; Choi, Cindy; Kennedy, Megan; Grigoriev, Igor V.; Pringle, Anne

    2015-01-01

    - The genus Amanita encompasses both symbiotic, ectomycorrhizal fungi and asymbiotic litter decomposers; all species are derived from asymbiotic ancestors. Symbiotic species are no longer able to degrade plant cell walls. The carbohydrate esterases family 1 (CE1s) is a diverse group of enzymes invol

  8. Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs

    Science.gov (United States)

    Necrotizing enterocolitis (NEC) remains the most severe gastrointestinal disorder in preterm infants. It is associated with the initiation of enteral nutrition and may be related to immature carbohydrate digestive capacity. We tested the hypothesis that a formula containing maltodextrin vs. lactose ...

  9. Protective group strategies in carbohydrate and peptide chemistry

    NARCIS (Netherlands)

    Ali, Asghar

    2010-01-01

    Protecting groups play a key role in the synthesis of complex natural products.This holds especially true for the synthesis of oligosaccharides, of which the monomeric carbohydrate building blocks usually contain up to five different hydroxyl functions. The discrimination of these hydroxyl functions

  10. Non-structural carbohydrates in woody plants compared among laboratories

    NARCIS (Netherlands)

    Quentin, Audrey G.; Pinkard, Elizabeth A.; Ryan, Michael G.; Tissue, David T.; Baggett, Scott L.; Adams, Henry D.; Maillard, Pascale; Marchand, Jacqueline; Landhäusser, Simon M.; Lacointe, André; Gibon, Yves; Anderegg, William R.L.; Asao, Shinichi; Atkin, Owen K.; Bonhomme, Marc; Claye, Caroline; Chow, Pak S.; Clément-Vidal, Anne; Davies, Noel W.; Dickman, Turin L.; Dumbur, Rita; Ellsworth, David S.; Falk, Kristen; Galiano, Lucía; Grünzweig, José M.; Hartmann, Henrik; Hoch, Günter; Hood, Sharon; Jones, Joanna E.; Koike, Takayoshi; Kuhlmann, Iris; Lloret, Francisco; Maestro, Melchor; Mansfield, Shawn D.; Martínez-Vilalta, Jordi; Maucourt, Mickael; McDowell, Nathan G.; Moing, Annick; Muller, Bertrand; Nebauer, Sergio G.; Niinemets, Ülo; Palacio, Sara; Piper, Frida; Raveh, Eran; Richter, Andreas; Rolland, Gaëlle; Rosas, Teresa; Joanis, Brigitte Saint; Sala, Anna; Smith, Renee A.; Sterck, Frank; Stinziano, Joseph R.; Tobias, Mari; Unda, Faride; Watanabe, Makoto; Way, Danielle A.; Weerasinghe, Lasantha K.; Wild, Birgit; Wiley, Erin; Woodruff, David R.

    2015-01-01

    Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to environmental conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked whether NSC estimates in the recent lite

  11. Protease-induced solubilisation of carbohydrates from brewers' spent grain

    NARCIS (Netherlands)

    Faulds, C.B.; Collins, S.; Robertson, J.A.; Treimo, J.; Eijsink, V.G.H.; Hinz, S.W.A.; Schols, H.A.; Buchert, J.; Waldron, K.W.

    2009-01-01

    The impact of microbial proteases on the release of carbohydrates from BSG was studied. The proteases were able to release the non-cellulosic glucose, a portion of feruloylated arabinoxylan and over 50% of the protein from brewers' spent grain (BSG) after 24 h hydrolysis. The non-cellulosic glucose

  12. Hydrolysis of Brewers' Spent Grain by Carbohydrate Degrading Enzymes

    NARCIS (Netherlands)

    Forssell, P.; Kontkanen, H.; Schols, H.A.; Hinz, S.W.A.; Eijsink, V.G.H.; Treimo, J.; Robertson, J.A.; Waldron, K.W.; Faulds, C.B.; Buchert, J.

    2008-01-01

    In this work four commercial cellulase-hemicellulase mixtures with different activity profiles were used for solubilization of carbohydrates from brewers' spent grain (BSG). After the enzyme treatment, both the solubilised fraction and the unhydrolysed residue were characterized. Treatment with 5,00

  13. Transporter’s evolution and carbohydrate metabolic clusters

    NARCIS (Netherlands)

    Plantinga, Titia H.; Does, Chris van der; Driessen, Arnold J.M.

    2004-01-01

    The yiaQRS genes of Escherichia coli K-12 are involved in carbohydrate metabolism. Clustering of homologous genes was found throughout several unrelated bacteria. Strikingly, all four bacterial transport protein classes were found, conserving transport function but not mechanism. It appears that dur

  14. Carbohydrate-related enzymes of important Phytophthora plant pathogens

    NARCIS (Netherlands)

    Brouwer, Henk; Coutinho, Pedro M; Henrissat, Bernard; de Vries, Ronald P; van den Brink, J.

    2014-01-01

    Carbohydrate-Active enZymes (CAZymes) form particularly interesting targets to study in plant pathogens. Despite the fact that many CAZymes are pathogenicity factors, oomycete CAZymes have received significantly less attention than effectors in the literature. Here we present an analysis of the CAZy

  15. Carbohydrate Staple Food Modulates Gut Microbiota of Mongolians in China

    Science.gov (United States)

    Li, Jing; Hou, Qiangchuan; Zhang, Jiachao; Xu, Haiyan; Sun, Zhihong; Menghe, Bilige; Zhang, Heping

    2017-01-01

    Gut microbiota is a determining factor in human physiological functions and health. It is commonly accepted that diet has a major influence on the gut microbial community, however, the effects of diet is not fully understood. The typical Mongolian diet is characterized by high and frequent consumption of fermented dairy products and red meat, and low level of carbohydrates. In this study, the gut microbiota profile of 26 Mongolians whom consumed wheat, rice and oat as the sole carbohydrate staple food for a week each consecutively was determined. It was observed that changes in staple carbohydrate rapidly (within a week) altered gut microbial community structure and metabolic pathway of the subjects. Wheat and oat favored bifidobacteria (Bifidobacterium catenulatum, Bifodobacteriumbifidum, Bifidobacterium adolescentis); whereas rice suppressed bifidobacteria (Bifidobacterium longum, Bifidobacterium adolescentis) and wheat suppresses Lactobaciilus, Ruminococcus and Bacteroides. The study exhibited two gut microbial clustering patterns with the preference of fucosyllactose utilization linking to fucosidase genes (glycoside hydrolase family classifications: GH95 and GH29) encoded by Bifidobacterium, and xylan and arabinoxylan utilization linking to xylanase and arabinoxylanase genes encoded by Bacteroides. There was also a correlation between Lactobacillus ruminis and sialidase, as well as Butyrivibrio crossotus and xylanase/xylosidase. Meanwhile, a strong concordance was found between the gastrointestinal bacterial microbiome and the intestinal virome. Present research will contribute to understanding the impacts of the dietary carbohydrate on human gut microbiome, which will ultimately help understand relationships between dietary factor, microbial populations, and the health of global humans. PMID:28377764

  16. Carbohydrates: How Carbs Fit into a Healthy Diet

    Science.gov (United States)

    ... You probably have also heard talk about the glycemic index. The glycemic index classifies carbohydrate-containing foods according to their potential ... sugar level. Weight-loss diets based on the glycemic index typically recommend limiting foods that are higher on ...

  17. DFT solvation studies of carbohydrates: implicit and explicit solvation

    Science.gov (United States)

    Solvents play a role in carbohydrate structure. Therefore, it is important to include solvation effects in calculations to allow a more realistic comparison with experimental data. A possible way to include solvation effects is to use implicit solvation models such as COSMO and PCM. Another avenu...

  18. Polysaccharide Biocatalysis : From Synthesizing Carbohydrate Standards to Establishing Characterization Methods

    NARCIS (Netherlands)

    Ciric, Jelena; Petrovic, Dejan M.; Loos, Katja

    2014-01-01

    Starch, glycogen, and cellulose are all around us. They are eaten and used on a daily basis but they are not understood completely. Even though these carbohydrates are simple, concerning their repeating unit, they are hard to characterize. In order to try to understand as much as possible about thei

  19. Cerebral carbohydrate cost of physical exertion in humans

    DEFF Research Database (Denmark)

    Dalsgaard, Mads K; Ogoh, Shigehiko; Dawson, Ellen A

    2004-01-01

    Above a certain level of cerebral activation the brain increases its uptake of glucose more than that of O(2), i.e., the cerebral metabolic ratio of O(2)/(glucose + 12 lactate) decreases. This study quantified such surplus brain uptake of carbohydrate relative to O(2) in eight healthy males who p...

  20. [Carbohydrate metabolism in the brain in comatose states].

    Science.gov (United States)

    Khapiĭ, Kh Kh; Gruzman, A B

    1990-01-01

    The article confirms an earlier discovered phenomenon that during comas and in post-coma periods the brain releases glucose and consumes lactate. It is suggested that the phenomenon is based on glucogenesis taking place in the brain from non-carbohydrate glucose precursors, which is phylogenetically predetermined and biologically expedient.

  1. Linking Bacillus cereus genotypes and carbohydrate utilization capacity

    NARCIS (Netherlands)

    Warda, Alicja K.; Siezen, Roland J.; Boekhorst, Jos; Wells-Bennik, Marjon H.J.; Jong, de Anne; Kuipers, Oscar P.; Nierop Groot, Masja N.; Abee, Tjakko

    2016-01-01

    We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together wi

  2. Linking Bacillus cereus Genotypes and Carbohydrate Utilization Capacity

    NARCIS (Netherlands)

    Warda, Alicja K.; Siezen, Roland J.; Boekhorst, Jos; Wells-Bennik, Marjon H.J.; Jong, de Anne; Kuipers, Oscar P.; Nierop Groot, Masja N.; Abee, Tjakko

    2016-01-01

    We characterised carbohydrate utilisation of 20 newly sequenced Bacillus cereus strains isolated from food products and food processing environments and two laboratory strains, B. cereus ATCC 10987 and B. cereus ATCC 14579. Subsequently, genome sequences of these strains were analysed together with

  3. Solid state conformational classification of eight-membered rings

    DEFF Research Database (Denmark)

    Pérez, J.; García, L.; Kessler, M.;

    2005-01-01

    A statistical classification of the solid state conformation in the title complexes using data retrieved from the Cambridge Structural Database (CSD) has been made. Phosphate and phosphinate complexes show a chair conformation preferably. In phosphonate complexes, the most frequent conformations...

  4. Differences in carbohydrate profiles in batch culture grown planktonic and biofilm cells of Amphora rostrata Wm. Sm

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Bhosle, N.B.

    modes of growth, the concentration of total carbohydrates, carbohydrate fractions, neutral carbohydrates, uronic acids and amino sugars in planktonic and biofilm cells of Amphora rostrata were measured. The results showed that the distribution...

  5. [Self-conciousness and conformity: moderating effects of conformity motives and task-interest].

    Science.gov (United States)

    Oshimi, T

    2000-10-01

    This study investigated the relationship between self-consciousness and conforming behavior, with conformity motives and task-interest as their moderator variables. One hundred fifty-six (156) participants were asked to imagine themselves in a hypothetical conforming situation, and estimate the probability of their conforming behavior and various conformity motives behind it, as well as their interest in the task. They also completed Self-Consciousness Scale. Among low task-interest participants, those high on private self-consciousness conformed more than the low if either motive for avoidance of isolation or motive for fairness was high, while those high on public self-consciousness conformed more than the low if motive for avoidance of isolation was high. Among high task-interest participants, those high on private self-consciousness conformed less than the low, while those high on public self-consciousness conformed more than the low if motive for fairness was high. The relationship between conformity motives and standards of behavior was discussed.

  6. Physiological aspects of energy metabolism and gastrointestinal effects of carbohydrates.

    Science.gov (United States)

    Elia, M; Cummings, J H

    2007-12-01

    The energy values of carbohydrates continue to be debated. This is because of the use of different energy systems, for example, combustible, digestible, metabolizable, and so on. Furthermore, ingested macronutrients may not be fully available to tissues, and the tissues themselves may not be able fully to oxidize substrates made available to them. Therefore, for certain carbohydrates, the discrepancies between combustible energy (cEI), digestible energy (DE), metabolizable energy (ME) and net metabolizable energy (NME) may be considerable. Three food energy systems are in use in food tables and for food labelling in different world regions based on selective interpretation of the digestive physiology and metabolism of food carbohydrates. This is clearly unsatisfactory and confusing to the consumer. While it has been suggested that an enormous amount of work would have to be undertaken to change the current ME system into an NME system, the additional changes may not be as great as anticipated. In experimental work, carbohydrate is high in the macronutrient hierarchy of satiation. However, studies of eating behaviour indicate that it does not unconditionally depend on the oxidation of one nutrient, and argue against the operation of a simple carbohydrate oxidation or storage model of feeding behaviour to the exclusion of other macronutrients. The site, rate and extent of carbohydrate digestion in, and absorption from the gut are key to understanding the many roles of carbohydrate, although the concept of digestibility has different meanings. Within the nutrition community, the characteristic patterns of digestion that occur in the small (upper) vs large (lower) bowel are known to impact in contrasting ways on metabolism, while in the discussion of the energy value of foods, digestibility is defined as the proportion of combustible energy that is absorbed over the entire length of the gastrointestinal tract. Carbohydrates that reach the large bowel are fermented to

  7. [Systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography].

    Science.gov (United States)

    Fu, Qing; Wang, Jun; Liang, Tu; Xu, Xiaoyong; Jin, Yu

    2013-11-01

    A systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography (HILIC) was performed. The influences of mobile phase, stationary phase and buffer salt on the retention of carbohydrates were investigated. According to the results, the retention time of carbohydrates decreased as the proportion of acetonitrile in mobile phase decreased. Increased time of carbohydrates was observed as the concentration of buffer salt in mobile phase increased. The retention behavior of carbohydrates was also affected by organic solvent and HILIC stationary phase. Furthermore, an appropriate retention equation was used in HILIC mode. The retention equation lnk = a + blnC(B) + cC(B) could quantitatively describe the retention factors of carbohydrates of plant origin with good accuracy: the relative error of the predicted time to actual time was less than 0.3%. The evaluation results could provide guidance for carbohydrates to optimize the experimental conditions in HILIC method development especially for carbohydrate separation

  8. Water and carbohydrate content at leafs of plants used in medicine during vegetation

    Directory of Open Access Journals (Sweden)

    Zhivetev M.A.

    2011-12-01

    Full Text Available Increase of carbohydrate content with cryoprotective function to the end of vegetation period was shown. The accumulation of carbohydrates in plants on Lake Baikal shores region was greater than it in Irkutsk region.

  9. Dietary advices on carbohydrate intake for pregnant women with type 1 diabetes

    DEFF Research Database (Denmark)

    Roskjær, Ann B; Andersen, Jens Rikardt; Ronneby, Helle;

    2015-01-01

    of Medicine (IOM) is generally recommended. A low-glycaemic index diet is considered safe, and has shown, positive effects on the glycaemic control and pregnancy outcomes for both healthy women, those with type 2 diabetic and gestational diabetes (GDM). In general, carbohydrate counting does improve glycaemic...... control in type 1 diabetes. A moderately low carbohydrate diet with a carbohydrate content of 40% of the calories results in better glycaemic control and comparable obstetric outcomes in type 2 diabetes and GDM when compared to a diet with a higher carbohydrate content, and is regarded safe in diabetic...... pregnancy. In type 1 diabetes pregnancy, a moderately low carbohydrate diet with 40% carbohydrates has been suggested; however, a minimum intake of 175 g carbohydrate daily is recommended. Despite limited evidence the combination of a low-glycaemic index diet with a moderately low carbohydrate intake, using...

  10. Dietary carbohydrate composition can change waste production and biofilter load in recirculating aquaculture systems

    NARCIS (Netherlands)

    Meriac, A.; Eding, E.H.; Schrama, J.W.; Kamstra, A.; Verreth, J.A.J.

    2014-01-01

    This study investigated the effect of dietary carbohydrate composition on the production, recovery and degradability of fecal waste from rainbow trout (Oncorhynchus mykiss) in recirculating aquaculture systems (RAS). Dietary carbohydrate composition was altered by substituting starch with non-starch

  11. Nickel-catalyzed proton-deuterium exchange (HDX) procedures for glycosidic linkage analysis of complex carbohydrates

    Science.gov (United States)

    The structural analysis of complex carbohydrates typically requires the assignment of three parameters: monosaccharide composition, the position of glycosidic linkages between monosaccharides, and the position and nature of non-carbohydrate substituents. The glycosidic linkage positions are often de...

  12. Characterization and optimization of carbohydrate production from an indigenous microalga Chlorella vulgaris FSP-E.

    Science.gov (United States)

    Ho, Shih-Hsin; Huang, Shu-Wen; Chen, Chun-Yen; Hasunuma, Tomohisa; Kondo, Akihiko; Chang, Jo-Shu

    2013-05-01

    In this study, three indigenous microalgae isolates were examined for their ability to produce carbohydrates. Among them, Chlorella vulgaris FSP-E displayed relatively high cell growth rate and carbohydrate content. The carbohydrate productivity of C. vulgaris FSP-E was further improved by using engineering strategies. The results show that using an appropriate light intensity and inoculum size could effectively promote cell growth and carbohydrate productivity. Nitrogen starvation triggered the accumulation of carbohydrates in the microalga, achieving a carbohydrate content of 51.3% after 4-day starvation. Under the optimal conditions, the highest biomass and carbohydrate productivity were 1.437 and 0.631 g L(-1) d(-1), respectively. This performance is better than that reported in most related studies. Since glucose accounted for nearly 93% of the carbohydrates accumulated in C. vulgaris FSP-E, the microalga is an excellent feedstock for bioethanol fermentation.

  13. Nitrogen and phosphorus removal coupled with carbohydrate production by five microalgae cultures cultivated in biogas slurry.

    Science.gov (United States)

    Tan, Fen; Wang, Zhi; Zhouyang, Siyu; Li, Heng; Xie, Youping; Wang, Yuanpeng; Zheng, Yanmei; Li, Qingbiao

    2016-12-01

    In this study, five microalgae strains were cultured for their ability to survive in biogas slurry, remove nitrogen resources and accumulate carbohydrates. It was proved that five microalgae strains adapted in biogas slurry well without ammonia inhibition. Among them, Chlorella vulgaris ESP-6 showed the best performance on carbohydrate accumulation, giving the highest carbohydrate content of 61.5% in biogas slurry and the highest ammonia removal efficiency and rate of 96.3% and 91.7mg/L/d respectively in biogas slurry with phosphorus and magnesium added. Additionally, the absence of phosphorus and magnesium that can be adverse for biomass accumulation resulted in earlier timing of carbohydrate accumulation and magnesium was firstly recognized and proved as the influence factor for carbohydrate accumulation. Microalgae that cultured in biogas slurry accumulated more carbohydrate in cell, making biogas slurry more suitable medium for the improvement of carbohydrate content, thus can be regarded as a new strategy to accumulate carbohydrate.

  14. Recovery from Cycling Exercise: Effects of Carbohydrate and Protein Beverages

    Directory of Open Access Journals (Sweden)

    Christopher J. Womack

    2012-06-01

    Full Text Available The effects of different carbohydrate-protein (CHO + Pro beverages were compared during recovery from cycling exercise. Twelve male cyclists (VO2peak: 65 ± 7 mL/kg/min completed ~1 h of high-intensity intervals (EX1. Immediately and 120 min following EX1, subjects consumed one of three calorically-similar beverages (285–300 kcal in a cross-over design: carbohydrate-only (CHO; 75 g per beverage, high-carbohydrate/low-protein (HCLP; 45 g CHO, 25 g Pro, 0.5 g fat, or low-carbohydrate/high-protein (LCHP; 8 g CHO, 55 g Pro, 4 g fat. After 4 h of recovery, subjects performed subsequent exercise (EX2; 20 min at 70% VO2peak + 20 km time-trial. Beverages were also consumed following EX2. Blood glucose levels (30 min after beverage ingestion differed across all treatments (CHO > HCLP > LCHP; p < 0.05, and serum insulin was higher following CHO and HCLP ingestion versus LCHP. Peak quadriceps force, serum creatine kinase, muscle soreness, and fatigue/energy ratings measured pre- and post-exercise were not different between treatments. EX2 performance was not significantly different between CHO (48.5 ± 1.5 min, HCLP (48.8 ± 2.1 min and LCHP (50.3 ± 2.7 min. Beverages containing similar caloric content but different proportions of carbohydrate/protein provided similar effects on muscle recovery and subsequent exercise performance in well-trained cyclists.

  15. Quality of Vegetable Waste Silages Treated with Various Carbohydrate Sources

    Directory of Open Access Journals (Sweden)

    R. Ridwan

    2013-08-01

    Full Text Available The aim of this research was to evaluate the quality of vegetable waste silages, using rice bran, onggok (cassava flour waste and pollard as carbohydrate sources. Vegetable waste was collected from local traditional market, consisted of corn husk, chinese cabbage and cabbage. Research was held in randomized block design consisted of six treatments with 3 replications. Treatments were (T1 vegetable waste + rice bran, (T2 vegetable waste + rice bran + rice straw, (T3 vegetable waste + onggok, (T4 vegetable waste + onggok + rice straw, (T5 vegetable waste + pollard, (T6 vegetable waste + pollard + rice straw. Lactobacillus plantarum 1A-2 was used as innoculant. The quality of silages was evaluated by measuring pH, temperature, population of lactic acid bacteria and lactic acid production. Nutrient characteristic was determined by proximate and fiber analysis. Results showed that pH of silages were not affected by treatments, but silage treated with rice bran, with or without rice straw addition, had higher temperature compared with others (29 oC or 28.3 oC. The highest population of lactic acid bacteria (1.65 x 109 cfu/g was found in silage using rice straw and onggok (T4, but the highest lactic acid production (0.41% was measured in silage using rice straw and rice bran (T2. In general, the use of rice bran as carbohydrate sources gave the highest lactic acid production followed by pollard and onggok. Different carbohydrate source gave different nutrients characteristic. Although the result was not significantly different, silage with highest protein content was measured in silage with pollard as carbohydrate source, followed with rice bran and onggok. The result showed that all carbohydrate sources used in this experiment can be used as silage ingredient resulting in good vegetable waste silage.

  16. Transcriptional regulation of the carbohydrate utilization network in Thermotoga maritima

    Directory of Open Access Journals (Sweden)

    Dmitry A Rodionov

    2013-08-01

    Full Text Available Hyperthermophilic bacteria from the Thermotogales lineage can produce hydrogen by fermenting a wide range of carbohydrates. Previous experimental studies identified a large fraction of genes committed to carbohydrate degradation and utilization in the model bacterium Thermotoga maritima. Knowledge of these genes enabled comprehensive reconstruction of biochemical pathways comprising the carbohydrate utilization network. However, transcriptional factors (TFs and regulatory mechanisms driving this network remained largely unknown. Here, we used an integrated approach based on comparative analysis of genomic and transcriptomic data for the reconstruction of the carbohydrate utilization regulatory networks in 11 Thermotogales genomes. We identified DNA-binding motifs and regulons for 19 orthologous TFs in the Thermotogales. The inferred regulatory network in T. maritima contains 181 genes encoding TFs, sugar catabolic enzymes and ABC-family transporters. In contrast to many previously described bacteria, a transcriptional regulation strategy of Thermotoga does not employ global regulatory factors. The reconstructed regulatory network in T. maritima was validated by gene expression profiling on a panel of mono- and disaccharides and by in vitro DNA-binding assays. The observed upregulation of genes involved in catabolism of pectin, trehalose, cellobiose, arabinose, rhamnose, xylose, glucose, galactose, and ribose showed a strong correlation with the UxaR, TreR, BglR, CelR, AraR, RhaR, XylR, GluR, GalR, and RbsR regulons. Ultimately, this study elucidated the transcriptional regulatory network and mechanisms controlling expression of carbohydrate utilization genes in T. maritima. In addition to improving the functional annotations of associated transporters and catabolic enzymes, this research provides novel insights into the evolution of regulatory networks in Thermotogales.

  17. Whey or Casein Hydrolysate with Carbohydrate for Metabolism and Performance in Cycling.

    Science.gov (United States)

    Oosthuyse, T; Carstens, M; Millen, A M E

    2015-07-01

    The protein type most suitable for ingestion during endurance exercise is undefined. This study compared co-ingestion of either 15 g/h whey or casein hydrolysate with 63 g/h fructose: maltodextrin (0.8:1) on exogenous carbohydrate oxidation, exercise metabolism and performance. 2 h postprandial, 8 male cyclists ingested either: carbohydrate-only, carbohydrate-whey hydrolysate, carbohydrate-casein hydrolysate or placebo-water in a crossover, double-blind design during 2 h of exercise at 60%W max followed by a 16-km time trial. Data were evaluated by magnitude-based inferential statistics. Exogenous carbohydrate oxidation, measured from (13)CO2 breath enrichment, was not substantially influenced by co-ingestion of either protein hydrolysate. However, only co-ingestion of carbohydrate-casein hydrolysate substantially decreased (98% very likely decrease) total carbohydrate oxidation (mean±SD, 242±44; 258±47; 277±33 g for carbohydrate-casein, carbohydrate-whey and carbohydrate-only, respectively) and substantially increased (93% likely increase) total fat oxidation (92±14; 83±27; 73±19 g) compared with carbohydrate-only. Furthermore, only carbohydrate-casein hydrolysate ingestion resulted in a faster time trial (-3.6%; 90% CI: ±3.2%) compared with placebo-water (95% likely benefit). However, neither protein hydrolysate enhanced time trial performance when compared with carbohydrate-only. Under the conditions of this study, ingesting carbohydrate-casein, but not carbohydrate-whey hydrolysate, favourably alters metabolism during prolonged moderate-strenuous cycling without substantially altering cycling performance compared with carbohydrate-only.

  18. Carbohydrate derived energy and gross energy absorption in preterm infants fed human milk or formula.

    OpenAIRE

    Curtis, M.; Senterre, J; Rigo, J; Putet, G.

    1986-01-01

    Significant production of breath hydrogen has been shown in premature infants, suggesting limited intestinal capacity for digestion of carbohydrate. To evaluate net absorption of carbohydrate 24 three day balance studies were carried out in seven preterm infants fed pasteurised banked human milk and in 17 preterm infants fed a formula containing 75% lactose and 25% glucose polymers. Because carbohydrate reaching the colon may be converted to organic acids by bacterial flora, carbohydrate net ...

  19. The Conformational Behaviour of the Odorant Dihydrocarveol

    Science.gov (United States)

    Loru, Donatella; Jarman, Natasha; Sanz, M. Eugenia

    2016-06-01

    The odorant dihydrocarveol (C10H18O) has been investigated in the gas phase using a 2-8 GHz chirped-pulse Fourier transform microwave spectrometer. Dihydrocarveol was purchased as a mixture of n-, iso-, neo-, and neoiso- isomers. The sample was placed in a bespoke heating nozzle at about 85°C and seeded in Ne at 5 bar. Three conformers were observed and their rotational constants were determined. By comparing the experimental rotational constants with those calculated ab initio the three conformers were identified as belonging to n-dihydrocarveol. In all three conformers the isopropenyl group is in equatorial position with respect to the six-membered ring, and the OH group maintains the same configuration. The conformers differ in the orientation of the isopropenyl group.

  20. Synthesis and conformational features of sym ,',"-triarylguanidines

    Indian Academy of Sciences (India)

    Kanniyappan Gopi; Brijesh Rathi; Natesan Thirupathi

    2010-03-01

    A one pot reaction involving sym ,'-diarylthiourea and the respective arylamine in the presence of aq. KOH in nitrobenzene at ≥ 105°C afforded sym ,',"-triarylguanidine in fair to good yield and the products have been characterized. Sym ,',"-tri(4-tolyl)guanidine possesses (7) anti-anti conformation, sym ,',"-tri(2-tolyl)guanidine (8) and sym ,',"-tris(2,4-xylyl)guanidine (11) each possess anti-anti conformation whereas sym ,',"-tris(2-anisyl)guanidine possesses (9) syn-anti conformation as determined by single crystal X-ray diffraction data. The observed conformations appear to result from a subtle balance between steric factor associated with the aryl substituent and multiple electronic factors namely - conjugation/negative hyperconjugation and non-covalent interactions in the crystal lattice.

  1. A probabilistic model of RNA conformational space

    DEFF Research Database (Denmark)

    Frellsen, Jes; Moltke, Ida; Thiim, Martin

    2009-01-01

    The increasing importance of non-coding RNA in biology and medicine has led to a growing interest in the problem of RNA 3-D structure prediction. As is the case for proteins, RNA 3-D structure prediction methods require two key ingredients: an accurate energy function and a conformational sampling...... procedure. Both are only partly solved problems. Here, we focus on the problem of conformational sampling. The current state of the art solution is based on fragment assembly methods, which construct plausible conformations by stringing together short fragments obtained from experimental structures. However...... efficient sampling of RNA conformations in continuous space, and with associated probabilities. We show that the model captures several key features of RNA structure, such as its rotameric nature and the distribution of the helix lengths. Furthermore, the model readily generates native-like 3-D...

  2. Social conformity despite individual preferences for distinctiveness.

    Science.gov (United States)

    Smaldino, Paul E; Epstein, Joshua M

    2015-03-01

    We demonstrate that individual behaviours directed at the attainment of distinctiveness can in fact produce complete social conformity. We thus offer an unexpected generative mechanism for this central social phenomenon. Specifically, we establish that agents who have fixed needs to be distinct and adapt their positions to achieve distinctiveness goals, can nevertheless self-organize to a limiting state of absolute conformity. This seemingly paradoxical result is deduced formally from a small number of natural assumptions and is then explored at length computationally. Interesting departures from this conformity equilibrium are also possible, including divergence in positions. The effect of extremist minorities on these dynamics is discussed. A simple extension is then introduced, which allows the model to generate and maintain social diversity, including multimodal distinctiveness distributions. The paper contributes formal definitions, analytical deductions and counterintuitive findings to the literature on individual distinctiveness and social conformity.

  3. Conformal higher-order viscoelastic fluid mechanics

    CERN Document Server

    Fukuma, Masafumi

    2012-01-01

    We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics. We then elaborately study the transient time scales at which the strain almost relaxes and becomes proportional to the gradients of velocity. We particularly show that a conformal second-order fluid with all possible parameters in the constitutive equations can be obtained without breaking the hypothesis of local thermodynamic equilibrium, if the conformal fluid is defined as the long time limit of a conformal second-order viscoelastic system. We also discuss how local thermodynamic equilibrium could be understood in the context of the fluid/gravity correspondence.

  4. Conformal higher-order viscoelastic fluid mechanics

    Science.gov (United States)

    Fukuma, Masafumi; Sakatani, Yuho

    2012-06-01

    We present a generally covariant formulation of conformal higher-order viscoelastic fluid mechanics with strain allowed to take arbitrarily large values. We give a general prescription to determine the dynamics of a relativistic viscoelastic fluid in a way consistent with the hypothesis of local thermodynamic equilibrium and the second law of thermodynamics. We then elaborately study the transient time scales at which the strain almost relaxes and becomes proportional to the gradients of velocity. We particularly show that a conformal second-order fluid with all possible parameters in the constitutive equations can be obtained without breaking the hypothesis of local thermodynamic equilibrium, if the conformal fluid is defined as the long time limit of a conformal second-order viscoelastic system. We also discuss how local thermodynamic equilibrium could be understood in the context of the fluid/gravity correspondence.

  5. Conformally covariant parametrizations for relativistic initial data

    Science.gov (United States)

    Delay, Erwann

    2017-01-01

    We revisit the Lichnerowicz-York method, and an alternative method of York, in order to obtain some conformally covariant systems. This type of parametrization is certainly more natural for non constant mean curvature initial data.

  6. Conformal Symmetries of Adiabatic Modes in Cosmology

    CERN Document Server

    Hinterbichler, Kurt; Khoury, Justin

    2012-01-01

    We remark on the existence of non-linearly realized conformal symmetries for scalar adiabatic perturbations in cosmology. These conformal symmetries are present for any cosmological background, beyond any slow-roll or quasi-de Sitter approximation. The dilatation transformation shifts the curvature perturbation by a constant, and corresponds to the well-known symmetry under spatial rescaling. We argue that the scalar sector is also invariant under special conformal transformations, which shift the curvature perturbation by a term linear in the spatial coordinates. We discuss whether these conformal symmetries can be extended to include tensor perturbations. Tensor modes introduce their own set of non-linearly realized symmetries. We identify an infinite set of large gauge transformations which maintain the transverse, traceless gauge condition, while shifting the tensor mode non-trivially.

  7. Structure of The Planar Galilean Conformal Algebra

    Science.gov (United States)

    Gao, Shoulan; Liu, Dong; Pei, Yufeng

    2016-08-01

    In this paper, we compute the low-dimensional cohomology groups of the planar Galilean conformal algebra introduced by Bagchi and Goparkumar. Consequently we determine its derivations, central extensions, and automorphisms.

  8. Film dosimetry in conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Danciu, C.; Proimos, B.S. [Patras Univ. (Greece). Dept. of Medical Physics

    1995-12-01

    Dosimetry, through a film sandwiched in a transverse cross-section of a solid phantom, is a method of choice in Conformal Radiotherapy because: (a) the blackness (density) of the film at each point offers a measure of the total dose received at that point, and (b) the film is easily calibrated by exposing a film strip in the same cross-section, through a stationary field. The film must therefore have the following properties: (a) it must be slow, in order not to be overexposed, even at a therapeutic dose of 200 cGy, and (b) the response of the film (density versus dose curve) must be independent of the photon energy spectrum. A few slow films were compared. It was found that the Kodak X-Omat V for therapy verification was the best choice. To investigate whether the film response was independent of the photon energy, response curves for six depths, starting from the depth of maximum dose to the depth of 25 cm, in solid phantom were derived. The vertical beam was perpendicular to the anterior surface of the phantom, which was at the distance of 100 cm from the source and the field was 15x15 cm at that distance. This procedure was repeated for photon beams emitted by a Cobalt-60 unit, two 6 MV and 15 MV Linear Accelerators, as well as a 45 MV Betatron. For each of those four different beams the film response was the same for all six depths. The results, as shown in the diagrams, are very satisfactory. The response curve under a geometry similar to that actually applied, when the film is irradiated in a transverse cross-section of the phantom, was derived. The horizontal beam was almost parallel (angle of 85) to the plane of the film. The same was repeated with the central ray parallel to the film (angle 90) and at a distance of 1.5 cm from the horizontal film. The field size was again 15x15 at the lateral entrance surface of the beam. The response curves remained the same, as when the beam was perpendicular to the films.

  9. Evaluation of certain crop residues for carbohydrate and protein fractions by cornell net carbohydrate and protein system

    Directory of Open Access Journals (Sweden)

    Venkateswarulu Swarna

    2015-06-01

    Full Text Available Four locally available crop residues viz., jowar stover (JS, maize stover (MS, red gram straw (RGS and black gram straw (BGS were evaluated for carbohydrate and protein fractions using Cornell Net Carbohydrate and Protein (CNCP system. Lignin (% NDF was higher in legume straws as compared to cereal stovers while Non-structural carbohydrates (NSC (% DM followed the reverse trend. The carbohydrate fractions A and B1 were higher in BGS while B2 was higher in MS as compared to other crop residues. The unavailable cell wall fraction (C was higher in legume straws when compared to cereal stovers. Among protein fractions, B1 was higher in legume straws when compared to cereal stovers while B2 was higher in cereal stovers as compared to legume straws. Fraction B3 largely, bypass protein was highest in MS as compared to other crop residues. Acid detergent insoluble crude protein (ADICP (% CP or unavailable protein fraction C was lowest in MS and highest in BGS. It is concluded that MS is superior in nutritional value for feeding ruminants as compared to other crop residues.

  10. Conformal transformation of tetrads and spin connection

    CERN Document Server

    Chakrabarty, Subhasish

    2016-01-01

    We investigate the conformal transformation of vierbein-Einstein-Palatini (VEP) action in terms of tetrads $e^I_\\mu$ and spin connection $A^{IJ}_\\mu$. The transformation of tetrads is obtained from that of the spacetime metric whereas that of the spin connection is not unique off-shell. When the connection can be completely expressed in terms of the tetrads, its transformation follows from that of the tetrads. We also construct the conformally invariant scalar field in the VEP formalism.

  11. On the stochastic dynamics of molecular conformation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    An important functioning mechanism of biological macromolecules is the transition between different conformed states due to thermal fluctuation. In the present paper, a biological macromolecule is modeled as two strands with side chains facing each other, and its stochastic dynamics including the statistics of stationary motion and the statistics of conformational transition is studied by using the stochastic averaging method for quasi Hamiltonian systems. The theoretical results are confirmed with the results from Monte Carlo simulation.

  12. Testing conformal mapping with kitchen aluminum foil

    CERN Document Server

    Haas, S; Crivelli, P

    2016-01-01

    We report an experimental verification of conformal mapping with kitchen aluminum foil. This experiment can be reproduced in any laboratory by undergraduate students and it is therefore an ideal experiment to introduce the concept of conformal mapping. The original problem was the distribution of the electric potential in a very long plate. The correct theoretical prediction was recently derived by A. Czarnecki (Can. J. Phys. 92, 1297 (2014)).

  13. On Useful Conformal Tranformations In General Relativity

    CERN Document Server

    Carneiro, D F; De Lima, A G; Shapiro, I L

    2004-01-01

    Local conformal transformations are known as a useful tool in various applications of the gravitational theory, especially in cosmology. We describe some new aspects of these transformations, in particular using them for derivation of Einstein equations for the cosmological and Schwarzschild metrics. Furthermore, the conformal transformation is applied for the dimensional reduction of the Gauss-Bonnet topological invariant in $d=4$ to the spaces of lower dimensions.

  14. On useful conformal tranformations in general relativity

    Science.gov (United States)

    Carneiro, D. F.; Freiras, E. A.; Gonçalves, B.; de Lima, A. G.; Shapiro, I.

    2004-12-01

    Local conformal transformations are known as a useful tool in various applications of the gravitational theory, especially in cosmology. We describe some new aspects of these transformations, in particular using them for derivation of Einstein equations for the cosmological and Schwarzschild metrics. Furthermore, the conformal transformation is applied for the dimensional reduction of the Gauss-Bonnet topological invariant in $d=4$ to the spaces of lower dimensions.

  15. The conformal transformation of the night sky

    Science.gov (United States)

    Minguzzi, E.

    2016-12-01

    We give a simple differential geometric proof of the conformal transformation of the night sky under change of observer. The proof does not use the four dimensionality of spacetime or spinor methods. Furthermore, it really shows that the result does not depend on Lorentz transformations. This approach, by giving a transparent covariant expression to the conformal factor, shows that in most situations it is possible to define a thermal sky metric independent of the observer.

  16. Social influences towards conformism in economic experiments

    OpenAIRE

    Hargreaves Heap, Shaun P.

    2014-01-01

    This paper reviews some of the economic experimental evidence on conformism. There is nothing to match the early psychology experiments where subjects were often swayed by the behaviour of others to an extraordinary degree, but there is plenty of evidence of conformism. This seems built-in to our sociality either because we have preferences for conversation or status which are activated by the knowledge of what others do, or because other people face relevantly similar decisions to our own an...

  17. Conformally Invariant Spinorial Equations in Six Dimensions

    CERN Document Server

    Batista, Carlos

    2016-01-01

    This work deals with the conformal transformations in six-dimensional spinorial formalism. Several conformally invariant equations are obtained and their geometrical interpretation are worked out. Finally, the integrability conditions for some of these equations are established. Moreover, in the course of the article, some useful identities involving the curvature of the spinorial connection are attained and a digression about harmonic forms and more general massless fields is made.

  18. Effective Conformal Descriptions of Black Hole Entropy

    Directory of Open Access Journals (Sweden)

    Steven Carlip

    2011-07-01

    Full Text Available It is no longer considered surprising that black holes have temperatures and entropies. What remains surprising, though, is the universality of these thermodynamic properties: their exceptionally simple and general form, and the fact that they can be derived from many very different descriptions of the underlying microscopic degrees of freedom. I review the proposal that this universality arises from an approximate conformal symmetry, which permits an effective “conformal dual” description that is largely independent of the microscopic details.

  19. 21 CFR 172.866 - Synthetic glycerin produced by the hydrogenolysis of carbohydrates.

    Science.gov (United States)

    2010-04-01

    ... of carbohydrates. 172.866 Section 172.866 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... produced by the hydrogenolysis of carbohydrates. Synthetic glycerin produced by the hydrogenolysis of carbohydrates may be safely used in food, subject to the provisions of this section: (a) It shall contain not...

  20. Sports Nutrition for the Primary Care Physician: The Importance of Carbohydrate.

    Science.gov (United States)

    Wheeler, Keith B.

    1989-01-01

    Discusses the relationship between nutrition and fatigue and how carbohydrates and timing of carbohydrate consumption can affect fatigued athletes. Nutrition plays a significant role in successful training and competition. Key concerns are the specific needs of athletes for carbohydrates before, during, and after exercise. (Author/SM)

  1. Carbohydrate-Loading: A Safe and Effective Method of Improving Endurance Performance.

    Science.gov (United States)

    Beeker, Richard T.; Israel, Richard G.

    Carbohydrate-loading prior to distance events is a common practice among endurance athletes. The purposes of this paper are to review previous research and to clarify misconceptions which may exist concerning carbohydrate-loading. The most effective method of carbohydrate-loading involves a training run of sufficient intensity and duration to…

  2. Virtual Issue: Carbohydrates in the 21(st) Century: Synthesis and Applications.

    Science.gov (United States)

    Fairbanks, Antony J

    2015-12-01

    Creative with carbohydrates! This Virtual Issue on Carbohydrates in the 21 (st) Century: Synthesis and Applications highlights current research in the carbohydrate field in which synthesis underpins the development of novel applications of sugar-based materials in medicine, diagnostics, and as antiinfectives.

  3. Virtual Issue: Carbohydrates in the 21st Century: Synthesis and Applications†

    OpenAIRE

    Antony J. Fairbanks

    2015-01-01

    Creative with carbohydrates! This Virtual Issue on Carbohydrates in the 21 st Century: Synthesis and Applications highlights current research in the carbohydrate field in which synthesis underpins the development of novel applications of sugar‐based materials in medicine, diagnostics, and as antiinfectives.

  4. Effect of Carbohydrate Ingestion on Ratings of Perceived Exertion during a Marathon.

    Science.gov (United States)

    Utter, Alan C.; Kang, Jie; Robertson, Robert J.; Nieman, David C.; Chaloupka, Edward C.; Suminski, Richard R.; Piccinni, Cristiana R.

    2002-01-01

    Investigated the effects of carbohydrate substrate availability on ratings of perceived exertion (RPE) and hormonal regulation during a competitive marathon. Data on marathon runners randomly assigned to receive carbohydrate or placebo indicated that those who ingested carbohydrate rather than placebo beverages were able to run at a higher…

  5. Randomized clinical trial comparing an oral carbohydrate beverage with placebo before laparoscopic cholecystectomy

    DEFF Research Database (Denmark)

    Bisgaard, T; Kristiansen, V B; Hjortsø, N C;

    2004-01-01

    .5 per cent carbohydrate-rich beverage the evening before operation (100 g carbohydrate) and another 400 ml (50 g carbohydrate) 2 h before initiation of anaesthesia, or the same volume of a placebo beverage. The primary endpoint was general well-being the day after operation. Patients were evaluated from...

  6. Novel anti-carbohydrate autoantibodies in patients with inflammatory bowel disease: are they useful for clinical practice?

    Science.gov (United States)

    Malickova, Karin; Lukas, Milan; Donoval, Robert; Sandova, Petra; Janatkova, Ivana

    2006-01-01

    The objective of this study was to test the diagnostic accuracy of novel anti-carbohydrate assays in patients with inflammatory bowel disease, namely in Crohn's disease. These carbohydrate assays are based on oligosaccharide chitobioside carbohydrate - anti-chitobioside carbohydrate antibodies (ACCA), laminaribioside carbohydrate anti-laminaribioside carbohydrate antibodies (ALCA), and mannobioside carbohydrate - anti-mannobioside carbohydrate antibodies (AMCA). We compared these assays with the anti-Saccharomyces cerevisiae antibodies (ASCA) assay. The results of this study suggest that ASCA are still the best serological marker for Crohn's disease. Further studies are required to explore the clinical utility of ACCA, ALCA and AMCA.

  7. Conformational proofreading: the impact of conformational changes on the specificity of molecular recognition.

    Directory of Open Access Journals (Sweden)

    Yonatan Savir

    Full Text Available To perform recognition, molecules must locate and specifically bind their targets within a noisy biochemical environment with many look-alikes. Molecular recognition processes, especially the induced-fit mechanism, are known to involve conformational changes. This raises a basic question: Does molecular recognition gain any advantage by such conformational changes? By introducing a simple statistical-mechanics approach, we study the effect of conformation and flexibility on the quality of recognition processes. Our model relates specificity to the conformation of the participant molecules and thus suggests a possible answer: Optimal specificity is achieved when the ligand is slightly off target; that is, a conformational mismatch between the ligand and its main target improves the selectivity of the process. This indicates that deformations upon binding serve as a conformational proofreading mechanism, which may be selected for via evolution.

  8. On being loud and proud: non-conformity and counter-conformity to group norms.

    Science.gov (United States)

    Hornsey, Matthew J; Majkut, Louise; Terry, Deborah J; McKimmie, Blake M

    2003-09-01

    Most experiments on conformity have been conducted in relation to judgments of physical reality; surprisingly few papers have experimentally examined the influence of group norms on social issues with a moral component. In response to this, participants were told that they were either in a minority or in a majority relative to their university group in terms of their attitudes toward recognition of gay couples in law (Expt 1: N = 205) and a government apology to Aborigines (Expt 2: N = 110). In both experiments, it was found that participants who had a weak moral basis for their attitude conformed to the group norm on private behaviours. In contrast, those who had a strong moral basis for their attitude showed non-conformity on private behaviours and counter-conformity on public behaviours. Incidences of non-conformity and counter-conformity are discussed with reference to theory and research on normative influence.

  9. Controlling complex networks with conformity behavior

    Science.gov (United States)

    Wang, Xu-Wen; Nie, Sen; Wang, Wen-Xu; Wang, Bing-Hong

    2015-09-01

    Controlling complex networks accompanied by common conformity behavior is a fundamental problem in social and physical science. Conformity behavior that individuals tend to follow the majority in their neighborhood is common in human society and animal communities. Despite recent progress in understanding controllability of complex networks, the existent controllability theories cannot be directly applied to networks associated with conformity. Here we propose a simple model to incorporate conformity-based decision making into the evolution of a network system, which allows us to employ the exact controllability theory to explore the controllability of such systems. We offer rigorous theoretical results of controllability for representative regular networks. We also explore real networks in different fields and some typical model networks, finding some interesting results that are different from the predictions of structural and exact controllability theory in the absence of conformity. We finally present an example of steering a real social network to some target states to further validate our controllability theory and tools. Our work offers a more realistic understanding of network controllability with conformity behavior and can have potential applications in networked evolutionary games, opinion dynamics and many other complex networked systems.

  10. Conformal symmetry and light flavor baryon spectra

    CERN Document Server

    Kirchbach, M

    2010-01-01

    The degeneracy among parity pairs systematically observed in the N and Delta spectra is interpreted as signature for conformal symmetry realization in the light flavor baryon sector in consequence of AdS/CFT. The case is made by showing that all the observed N and Delta resonances with masses below 2500 MeV distribute fairly well over the first levels of a unitary representation of the conformal group, a representation that covers the spectrum of a quark-diquark system, placed directly on the AdS_5 cone, conformally compactified to R^1*S^3. The free geodesic motion on the S^3 manifold is described by means of the scalar conformal equation there, which is of the Klein-Gordon type. The equation is then gauged by the "curved" Coulomb potential that has the form of a cotangent function. Conformal symmetry is not exact, this because the gauge potential slightly modifies the conformal centrifugal barrier of the free geodesic motion. Thanks to this, the degeneracy between P11-S11 pairs from same level is relaxed, wh...

  11. Conformational properties of oxazoline-amino acids

    Science.gov (United States)

    Staś, Monika; Broda, Małgorzata A.; Siodłak, Dawid

    2016-04-01

    Oxazoline-amino acids (Xaa-Ozn) occur in natural peptides of potentially important bioactivity. The conformations of the model compounds: Ac-(S)-Ala-Ozn(4R-Me), Ac-(S)-Ala-Ozn(4S-Me), and (gauche+, gauche-, anti) Ac-(S)-Val-Ozn(4R-Me) were studied at meta-hybrid M06-2X/6-311++G(d,p) method including solvent effect. Boc-L-Ala-L-Ozn-4-COOMe and Boc-L-Val-L-Ozn-4-COOMe were synthesized and studied by FT-IR and NMR-NOE methods. The conformations in crystal state were gathered from the Cambridge Structural Data Base. The main conformational feature of the oxazoline amino acids is the conformation β2 (ϕ,ψ ∼ -161°, -6°), which predominates in weakly polar environment and still is accessible in polar surrounding. The changes of the conformational preferences towards the conformations αR (ϕ,ψ ∼ -70°, -15°) and then β (ϕ,ψ ∼ -57°, -155°) are observed with increase of the environment polarity.

  12. Foliar carbohydrate differs betweenPicea crassifolia and Sabina przewalskii with the altitudinal variation of Qilian Mountains, China

    Institute of Scientific and Technical Information of China (English)

    ManXiao Zhang; HuiJuan Pei; YouFu Zhang; Tuo Chen; GuangXiu Liu

    2015-01-01

    Nonstructural carbohydrates (NSC) and nitrogen metabolism strongly influence growth and development in plants. The biosynthesis of cellulose and lignin (structural carbohydrates, SC) depends largely on the supply of NSC. We desire to examine which hypothesis, carbon limitation or growth limitation, best fits the alpine plant response between NSC, SC, carbon (C), nitrogen (N) and altitude. We compared the foliar concentrations of carbohydrates, C and N between the leaves ofPicea crassifolia (lower-elevation tree-line species) andSabina przewalskii (high-elevation tree-line species) in their response to changing elevation. Our site was located in the mid-northern area of Qilian Mountains, China. We found that foliar soluble sugar (SG)concentrations were significantly higher inP. crassifolia than inS. przewalskiiat the 2,700–3,400 m level. Foliar NSC levels inP. crassifolia increased at the 2,700–3,100 m level, indicating that growth was limited gradually resulting in a surplus of NSC (to conform to GLH), subsequently decreasing at the 3,100–3,400 m level, the assimilation declined leading to C deficit (to conform to CLH). SC (SC metabolism disorders at 3,100–3,400 m), C, N and starch were significantly lower inP. crassifolia than inS. przewalskii. Conversely, foliar SG concentration shows a fall-rise trend with increasing elevation forS. przewalskii. SC concentration inS. przewalskii leaves decreased with an increase of elevation and has a significantly positive correlation to N concentration marking the assimilation of plants. Therefore, the high-elevation tree-line species (S. przewalskii) utilize or store more foliar SG leading to a decrease of SG concentration for survival and growth/regrowth in an adverse environment, higher total C, N, SC, starch contents and lower NSC level. Also, their change trends along the elevational gradient in leaves ofS. przewalskii indicate better assimilation strategies for SG use under environmental stress compared to

  13. Effect of the secondary structure of carbohydrate residues of alpha 1-acid glycoprotein (orosomucoid) on the local dynamics of Trp residues.

    Science.gov (United States)

    Albani, Jihad René

    2004-01-01

    We studied in this work the relation between the secondary structure of the carbohydrate residues of alpha1-acid glycoprotein and the local motions of Trp residues of the protein. We measured for this purpose the fluorescence emission intensity and anisotropy of the Trp residues between -46 and +30 degrees of the sialylated and asialylated protein. Our results indicate that, in both forms, the global profile of the emission intensity with temperature shows that Trp residues display static and collisional interaction with the neighboring amino acids. However, the profile of the asialylated form is more structured than that observed for the sialylated protein. The Y-plot analysis of the emission-anisotropy results indicated that the frictional resistance to rotation of the surface Trp residue is less important in the sialylated protein than in the asialylated form. This result is in good agreement with the fact that, in the asialylated conformation, the carbohydrate residues are closer to the protein surface than in the sialylated form, thereby increasing the contact of the surface Trp residue with the neighboring amino acids. Also, the interaction between the carbohydrate residues and the surface Trp residue contributes to the modification of the frictional resistance to rotation of the fluorophore.

  14. Method for improving separation of carbohydrates from wood pulping and wood or biomass hydrolysis liquors

    Science.gov (United States)

    Griffith, William Louis; Compere, Alicia Lucille; Leitten, Jr., Carl Frederick

    2010-04-20

    A method for separating carbohydrates from pulping liquors includes the steps of providing a wood pulping or wood or biomass hydrolysis pulping liquor having lignin therein, and mixing the liquor with an acid or a gas which forms an acid upon contact with water to initiate precipitation of carbohydrate to begin formation of a precipitate. During precipitation, at least one long chain carboxylated carbohydrate and at least one cationic polymer, such as a polyamine or polyimine are added, wherein the precipitate aggregates into larger precipitate structures. Carbohydrate gel precipitates are then selectively removed from the larger precipitate structures. The method process yields both a carbohydrate precipitate and a high purity lignin.

  15. A glycoconjugate of Haemophilus influenzae Type b capsular polysaccharide with tetanus toxoid protein: hydrodynamic properties mainly influenced by the carbohydrate.

    Science.gov (United States)

    Abdelhameed, Ali Saber; Adams, Gary G; Morris, Gordon A; Almutairi, Fahad M; Duvivier, Pierre; Conrath, Karel; Harding, Stephen E

    2016-02-26

    Three important physical properties which may affect the performance of glycoconjugate vaccines against serious disease are molar mass (molecular weight), heterogeneity (polydispersity), and conformational flexibility in solution. The dilute solution behaviour of native and activated capsular polyribosylribitol (PRP) polysaccharides extracted from Haemophilus influenzae type b (Hib), and the corresponding glycoconjugate made by conjugating this with the tetanus toxoid (TT) protein have been characterized and compared using a combination of sedimentation equilibrium and sedimentation velocity in the analytical ultracentrifuge with viscometry. The weight average molar mass of the activated material was considerably reduced (Mw ~ 0.24 × 10(6) g.mol(-1)) compared to the native (Mw ~ 1.2 × 10(6) g.mol(-1)). Conjugation with the TT protein yielded large polydisperse structures (of Mw ~ 7.4 × 10(6) g.mol(-1)), but which retained the high degree of flexibility of the native and activated polysaccharide, with frictional ratio, intrinsic viscosity, sedimentation conformation zoning behaviour and persistence length all commensurate with highly flexible coil behaviour and unlike the previously characterised tetanus toxoid protein (slightly extended and hydrodynamically compact structure with an aspect ratio of ~3). This non-protein like behaviour clearly indicates that it is the carbohydrate component which mainly influences the physical behaviour of the glycoconjugate in solution.

  16. Carbohydrates in diversity-oriented synthesis: challenges and opportunities.

    Science.gov (United States)

    Lenci, E; Menchi, G; Trabocchi, A

    2016-01-21

    Over the last decade, Diversity-Oriented Synthesis (DOS) has become a new paradigm for developing large collections of structurally diverse small molecules as probes to investigate biological pathways, and to provide a larger array of the chemical space. Drug discovery and chemical biology are taking advantage of DOS approaches to exploit highly-diverse and complex molecular platforms, producing advances in both target and ligand discovery. In this view, carbohydrates are attractive building blocks for DOS libraries, due to their stereochemical diversity and high density of polar functional groups, thus offering many possibilities for chemical manipulation and scaffold decoration. This review will discuss research contributions and perspectives on the application of carbohydrate chemistry to explore the accessible chemical space through appendage, stereochemical and scaffold diversity.

  17. Template free synthesis of natural carbohydrates functionalised fluorescent silver nanoclusters.

    Science.gov (United States)

    Ebrahiminezhad, Alireza; Berenjian, Aydin; Ghasemi, Younes

    2016-06-01

    Template-assisted synthesis is one of the most recognised techniques for fabrication of silver nanoclusters (AgNCs). However, this process is time consuming, toxic and expensive. In this study, the authors report a completely novel approach for the green and facile synthesis of AgNCs using Matricaria chamomilla, without any additional template. Fluorescent and colloidally stable AgNCs with average particle size of 2.4 nm were successfully produced. They found that carbohydrates from Matricaria chamomilla act as an ideal template to generate fluorescent AgNCs. Moreover, oxygen-bearing functional groups were validated to be the active groups for anchoring and reducing of Ag(+) ions. The novel carbohydrate coating method makes the prepared nanoclusters completely hydrophilic and stable in aqueous matrices.

  18. Carbohydrate-based cancer vaccines: target cancer with sugar bullets.

    Science.gov (United States)

    Liu, Chang-Cheng; Ye, Xin-Shan

    2012-08-01

    With the booming development of glycobiology and glycochemistry, more and more structures of tumor-associated carbohydrate antigens (TACAs) are identified. Their broad expression and high specificity in cancer make them important targets to develop cancer vaccines or immunotherapies. However, most of the TACAs are T cell-independent antigens, they cannot elicit a powerful enough immune response to prevent or treat cancer. Immunotolerance and immunosuppression are more easily induced due to their endogenous properties and the declining immunity of the patients. This review summarizes the recent efforts to overcome these obstacles: coupling the carbohydrate antigens to proper carriers such as proteins or some small molecule carriers, and chemically modifying the structures of the TACAs to enhance the immunogenicity of TACAs and break the immunotolerance.

  19. Does caffeine alter muscle carbohydrate and fat metabolism during exercise?

    DEFF Research Database (Denmark)

    Graham, Terry E; Battram, Danielle S; Dela, Flemming

    2008-01-01

    and carbohydrate metabolism. While caffeine certainly mobilizes fatty acids from adipose tissue, rarely have measures of the respiratory exchange ratio indicated an increase in fat oxidation. However, this is a difficult measure to perform accurately during exercise, and small changes could be physiologically......Caffeine, an adenosine receptor antagonist, has been studied for decades as a putative ergogenic aid. In the past 2 decades, the information has overwhelmingly demonstrated that it indeed is a powerful ergogenic aid, and frequently theories have been proposed that this is due to alterations in fat...... important. The few studies examining human muscle metabolism directly have also supported the fact that there is no change in fat or carbohydrate metabolism, but these usually have had a small sample size. We combined the data from muscle biopsy analyses of several similar studies to generate a sample size...

  20. Effects of polymeric carbohydrates on growth and development

    DEFF Research Database (Denmark)

    Knudsen, Knud Erik Bach

    , metabolized and net energy); available energy relative to protein is crucial for performance and carcass quality; second, the proportion of starch to NSP will influence rate and type of metabolites (glucose vs. SCFA) deriving from carbohydrate assimilation, and finally, type of starch (types A, B, and C......The main objective of the presentation is to provide insight into the role of polymeric carbohydrates in growth and development of pigs. Polymeric carbohydrates—starch and non-starch polysaccharides (NSP)—quantitatively represent the largest portion of the diets for pigs and are therefore...... by the microflora in the large intestine. Starch degradation leads to the release of glucose which is absorbed by an active absorption process that triggers the release of insulin from the pancreas, whereas the fermentation of NSP to short-chain fatty acids (SCFA: acetate, propionate and butyrate) occurs...

  1. Natural Cytotoxicity Receptors: Pattern Recognition and Involvement of Carbohydrates

    Directory of Open Access Journals (Sweden)

    Angel Porgador

    2005-01-01

    Full Text Available Natural cytotoxicity receptors (NCRs, expressed by natural killer (NK cells, trigger NK lysis of tumor and virus-infected cells on interaction with cell-surface ligands of these target cells. We have determined that viral hemagglutinins expressed on the surface of virus-infected cells are involved in the recognition by the NCRs, NKp44 and NKp46. Recognition of tumor cells by the NCRs NKp30 and NKp46 involves heparan sulfate epitopes expressed on the tumor cell membrane. Our studies provide new evidence for the identity of the ligands for NCRs and indicate that a broader definition should be applied to pathological patterns recognized by innate immune receptors. Since nonmicrobial endogenous carbohydrate structures contribute significantly to this recognition, there is an imperative need to develop appropriate tools for the facile sequencing of carbohydrate moieties.

  2. High throughput screening of starch structures using carbohydrate microarrays

    DEFF Research Database (Denmark)

    Tanackovic, Vanja; Rydahl, Maja Gro; Pedersen, Henriette Lodberg

    2016-01-01

    In this study we introduce the starch-recognising carbohydrate binding module family 20 (CBM20) from Aspergillus niger for screening biological variations in starch molecular structure using high throughput carbohydrate microarray technology. Defined linear, branched and phosphorylated...... maltooligosaccharides, pure starch samples including a variety of different structures with variations in the amylopectin branching pattern, amylose content and phosphate content, enzymatically modified starches and glycogen were included. Using this technique, different important structures, including amylose content...... and branching degrees could be differentiated in a high throughput fashion. The screening method was validated using transgenic barley grain analysed during development and subjected to germination. Typically, extreme branching or linearity were detected less than normal starch structures. The method offers...

  3. Simple mucin-type carbohydrate antigens in pleomorphic adenomas

    DEFF Research Database (Denmark)

    Therkildsen, M H; Mandel, U; Christensen, M

    1993-01-01

    Simple mucin-type carbohydrate structures, T, Tn and sialosyl-Tn, are regarded as general markers of carcinomas in several epithelial tissues as a result of incomplete synthesis with precursor accumulation. The structures have a very limited distribution in normal tissues and secretions, including...... saliva and salivary glands. The expression of simple mucin-type carbohydrate structures and ABH(O) variants was studied in paraffin-embedded and frozen tissue sections from 37 pleomorphic adenomas with associated normal parotid tissue, using immunohistology and a panel of MAbs with well......-defined specificity for T, Tn, sialosyl-Tn, and blood group H and A variants hereof. The immature Tn and sialosyl-Tn antigen structures were expressed in the epithelial ductular structures of the tumors, whereas they were almost absent from normal parotid tissue, indicating aberrant glycosylation with accumulation...

  4. Vaccines based on the cell surface carbohydrates of pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Jones Christopher

    2005-01-01

    Full Text Available Glycoconjugate vaccines, in which a cell surface carbohydrate from a micro-organism is covalently attached to an appropriate carrier protein are proving to be the most effective means to generate protective immune responses to prevent a wide range of diseases. The technology appears to be generic and applicable to a wide range of pathogens, as long as antibodies against surface carbohydrates help protect against infection. Three such vaccines, against Haemophilus influenzae type b, Neisseria meningitidis Group C and seven serotypes of Streptococcus pneumoniae, have already been licensed and many others are in development. This article discusses the rationale for the development and use of glycoconjugate vaccines, the mechanisms by which they elicit T cell-dependent immune responses and the implications of this for vaccine development, the role of physicochemical methods in the characterisation and quality control of these vaccines, and the novel products which are under development.

  5. Normal Roles for Dietary Fructose in Carbohydrate Metabolism

    Directory of Open Access Journals (Sweden)

    Maren R. Laughlin

    2014-08-01

    Full Text Available Although there are many well-documented metabolic effects linked to the fructose component of a very high sugar diet, a healthy diet is also likely to contain appreciable fructose, even if confined to that found in fruits and vegetables. These normal levels of fructose are metabolized in specialized pathways that synergize with glucose at several metabolic steps. Glucose potentiates fructose absorption from the gut, while fructose catalyzes glucose uptake and storage in the liver. Fructose accelerates carbohydrate oxidation after a meal. In addition, emerging evidence suggests that fructose may also play a role in the secretion of insulin and GLP-1, and in the maturation of preadipocytes to increase fat storage capacity. Therefore, fructose undergoing its normal metabolism has the interesting property of potentiating the disposal of a dietary carbohydrate load through several routes.

  6. P. Mackay on Conformism, Non-Conformism and Anti-Conformism in the Culture of the United States, ed. by A. Balasopoulos et al.

    OpenAIRE

    2009-01-01

    Conformism, Non-Conformism and Anti-Conformism in the Culture of the United States. European Views of the United States. Vol. 1. Eds. Antonis Balasopoulos, Gesa Mackenthun and Theodora Tsimpouki. Heidelberg: Universitätverlag, 2008. pp. 330. ISBN 978-3-8253-5479-4.   This volume comes out of the 2006 EAAS Conference hosted by the University of Cyprus. The book explores expressions of conformism, non-conformism, and anti-conformism in American culture from the nineteenth century to the presen...

  7. P. Mackay on Conformism, Non-Conformism and Anti-Conformism in the Culture of the United States, ed. by A. Balasopoulos et al.

    Directory of Open Access Journals (Sweden)

    2009-02-01

    Full Text Available Conformism, Non-Conformism and Anti-Conformism in the Culture of the United States. European Views of the United States. Vol. 1. Eds. Antonis Balasopoulos, Gesa Mackenthun and Theodora Tsimpouki. Heidelberg: Universitätverlag, 2008. pp. 330. ISBN 978-3-8253-5479-4.  This volume comes out of the 2006 EAAS Conference hosted by the University of Cyprus. The book explores expressions of conformism, non-conformism, and anti-conformism in American culture from the nineteenth century to the present....

  8. Low-carbohydrate diets and prostate cancer: how low is "low enough"?

    Science.gov (United States)

    Masko, Elizabeth M; Thomas, Jean A; Antonelli, Jodi A; Lloyd, Jessica C; Phillips, Tameika E; Poulton, Susan H; Dewhirst, Mark W; Pizzo, Salvatore V; Freedland, Stephen J

    2010-09-01

    Previous studies indicate that carbohydrate intake influences prostate cancer biology, as mice fed a no-carbohydrate ketogenic diet (NCKD) had significantly smaller xenograft tumors and longer survival than mice fed a Western diet. As it is nearly impossible for humans to consume and maintain NCKD, we determined whether diets containing 10% or 20% carbohydrate kcal showed similar tumor growth as NCKD. A total of 150 male severe combined immunodeficient mice were fed a Western diet ad libitum, injected with the human prostate cancer cell line LAPC-4, and then randomized 2 weeks later to one of three arms: NCKD, 10% carbohydrate, or 20% carbohydrate diets. Ten mice not injected were fed an ad libitum low-fat diet (12% fat kcal) serving as the reference in a modified-paired feeding protocol. Mice were sacrificed when tumors reached 1,000 mm(3). Despite consuming extra calories, all mice receiving low-carbohydrate diets were significantly lighter than those receiving a low-fat diet (P Diet did not affect survival (P = 0.34). There were no differences in serum insulin-like growth factor-I or insulin-like growth factor binding protein-3 at sacrifice among the low-carbohydrate arms (P = 0.07 and P = 0.55, respectively). Insulin was significantly lower in the 20% carbohydrate arm (P = 0.03). LAPC-4 xenograft mice fed a low-carbohydrate diet (10-20% carbohydrate kcal) had similar survival as mice consuming NCKD (0% carbohydrate kcal).

  9. KINETICS OF DELIGNIFICATION AND CARBOHYDRATE DEGRADATION DURING OXYGEN BLEACHING

    Institute of Scientific and Technical Information of China (English)

    K.LNguyen

    2004-01-01

    Carbohydrate degradation during oxygen bleaching isassociated with cleavage reactions. It is apparent thatthe loss of the cellulose DPis strongly affected by(degree ofpolymisation) the extent of thedelignification. A strong linear correlation can beestablished between the DP of cellulose chains andthe residual lignin in the pulp. The Nuclear Growthconcept and Percolation Theory for heterogenoussystem can be combined to formulate kinetic modelsfor both the delignification and the degradation ofcarbohydrate. The models prediction is statisticallyrobust and can be applied to different pulps atdifferent bleachin~ conditions.

  10. Impeded Carbohydrate Metabolism in Rice Plants under Submergence Stress

    Institute of Scientific and Technical Information of China (English)

    Malay Kumar ADAK; Nirmalya GHOSH; Dilip Kumar DASGUPTA; Sudha GUPTA

    2011-01-01

    The detrimental effects of submergence on physiological performances of some rice varieties with special references to carbohydrate metabolisms and their allied enzymes during post-flowering stages have been documented and clarified in the present investigation.It was found that photosynthetic rate and concomitant translocation of sugars into the panicles were both related to the yield.The detrimental effects of the complete submergence were recorded in generation of sucrose,starch,sucrose phosphate synthase and phosphorylase activity in the developing panicles of the plants as compared to those under normal or control (i.e.non-submerged) condition.The accumulation of starch was significantly lower in plants under submergence and that was correlated with ADP-glucose pyrophosphorylase activity.Photosynthetic rate was most affected under submergence in varying days of post-flowering and was also related to the down regulation of Ribulose bisphosphate carboxylase activity.However,under normal or control condition,there recorded a steady maintenance of photosynthetic rate at the post-flowering stages and significantly higher values of Ribulose bisphosphate carboxylase activity.Still,photosynthetic rate of the plants under both control and submerged conditions had hardly any significant correlation with sugar accumulation and other enzymes of carbohydrate metabolism like invertase with grain yield.Finally,plants under submergence suffered significant loss of yield by poor grain filling which was related to impeded carbohydrate metabolism in the tissues.It is evident that loss of yield under submergence is attributed both by lower sink size or sink capacity (number of panicles,in this case) as well as subdued carbohydrate metabolism in plants and its subsequent partitioning into the grains.

  11. Distribution of particulate carbohydrate species in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B; Bhosle, N.B; Gopalakrishna, V.V

    carbohydrate (TPCHO) and total particulate uronic acids (TPURA). The concentrations of POC, TPCHO and TPURA varied from 4.80 to 29.12, 0.85 to 4.24, 0.09 to 0.91 mu M C, respectively. The TPCHO-C and TPURA-C accounted for 6.6-32.5 % and 0.87-3.65 % of POC...

  12. Carbohydrate metabolism in the mosquito pathogen Bacillus sphaericus 2362.

    OpenAIRE

    Russell, B L; Jelley, S A; Yousten, A A

    1989-01-01

    Bacillus sphaericus 2362 is pathogenic for mosquito larvae and is being considered for large-scale production as a larvicide. The inability of the bacteria to metabolize carbohydrates requires that they be grown on proteinaceous media. This bacterium was found to be unable to transport glucose or sucrose into the cell, and it lacked glucokinase and hexokinase activity. In addition, it lacked phosphoglucose isomerase, phosphofructokinase, and glucose 6-phosphate dehydrogenase, which are early ...

  13. Carbohydrate maldigestion induces necrotizing enterocolitis in preterm pigs.

    Science.gov (United States)

    Thymann, Thomas; Møller, Hanne K; Stoll, Barbara; Støy, Ann Cathrine F; Buddington, Randal K; Bering, Stine B; Jensen, Bent B; Olutoye, Oluyinka O; Siggers, Richard H; Mølbak, Lars; Sangild, Per T; Burrin, Douglas G

    2009-12-01

    Necrotizing enterocolitis (NEC) remains the most severe gastrointestinal disorder in preterm infants. It is associated with the initiation of enteral nutrition and may be related to immature carbohydrate digestive capacity. We tested the hypothesis that a formula containing maltodextrin vs. a formula containing lactose as the principal source of carbohydrate would predispose preterm pigs to a higher NEC incidence. Cesarean-derived preterm pigs were given total parenteral nutrition for 48 h followed by total enteral nutrition with a lactose-based (n = 11) or maltodextrin-based (n = 11) formula for 36 h. A higher incidence (91% vs. 27%) and severity (score of 3.3 vs. 1.8) of NEC were observed in the maltodextrin than in the lactose group. This higher incidence of NEC in the maltodextrin group was associated with significantly lower activities of lactase, maltase, and aminopeptidase; reduced villus height; transiently reduced in vivo aldohexose uptake; and reduced ex vivo aldohexose uptake capacity in the middle region of the small intestine. Bacterial diversity was low for both diets, but alterations in bacterial composition and luminal concentrations of short-chain fatty acids were observed in the maltodextrin group. In a second study, we quantified net portal absorption of aldohexoses (glucose and galactose) during acute jejunal infusion of a maltodextrin- or a lactose-based formula (n = 8) into preterm pigs. We found lower net portal aldohexose absorption (4% vs. 42%) and greater intestinal recovery of undigested carbohydrate (68% vs. 27%) in pigs acutely perfused with the maltodextrin-based formula than those perfused with the lactose-based formula. The higher digestibility of the lactose than the maltodextrin in the formulas can be attributed to a 5- to 20-fold higher hydrolytic activity of tissue-specific lactase than maltases. We conclude that carbohydrate maldigestion is sufficient to increase the incidence and severity of NEC in preterm pigs.

  14. Maximizing Immune Response to Carbohydrate Antigens on Breast Tumors

    Science.gov (United States)

    2005-08-01

    Emmons, Ph.D. CONTRACTING ORGANIZATION: University of Arkansas for Medical Sciences Little Rock, Arkansas 72205 REPORT DATE: August 2005 TYPE OF REPORT...SUBTITLE 5a. CONTRACT NUMBER Maximizing Immune Response to Carbohydrate Antigens on Breast Tumors 5b. GRANT NUMBER DAMD17-01-1-0366 5c. PROGRAM...binding affinities of peptide and carbohyd- Hollingsworth, M. A. 1997. Oligosaccharides expressed on MUCl rate with I-A’ will be illuminating. However

  15. Polycations. 17. Synthesis and properties of polycationic derivatives of carbohydrates.

    Science.gov (United States)

    Thomas, Marie; Montenegro, Diego; Castaño, Alejandra; Friedman, Laura; Leb, Jay; Huang, Mia Lace; Rothman, Leah; Lee, Heidi; Capodiferro, Craig; Ambinder, Daniel; Cere, Eva; Galante, Jessica; Rizzo, JaimeLee; Melkonian, Karin; Engel, Robert

    2009-09-08

    In our continuing investigation of polycationic salts for purposes of antimicrobial action, ion-channel blocking, and construction of ionic liquids, we have prepared several series of polycationic salts derived from carbohydrate precursors. These salts are currently being investigated for optimal efficacy as antibacterials and antifungals, as well as for other applications. The syntheses of such series of salts are described here along with preliminary antibacterial testing results and a discussion of their properties indicating their potential utility for several purposes.

  16. Glass transition phenomena applied to powdered amorphous food carbohydrates

    OpenAIRE

    Ronkart, Sebastien N; Blecker, Christophe; Deroanne, Claude; Paquot, Michel

    2009-01-01

    Glass transition phenomena applied to powdered amorphous food carbohydrates. During these last fifteen years, some food technologists and scientists have become aware of the importance of the glass transition, a thermal property of glassy or amorphous material, in food preparation processes. Recent studies have successfully correlated this fundamental notion to technofunctional changes within the powder. The aim of this paper is to present in a non exhaustive manner the relationship between g...

  17. A randomized trial of preoperative oral carbohydrates in abdominal surgery

    OpenAIRE

    Sada, Fatos; Krasniqi, Avdyl; Hamza, Astrit; Gecaj-Gashi, Agreta; Bicaj, Besnik; Kavaja, Floren

    2014-01-01

    Background Carbohydrate-rich liquid drinks (CRLDs) have been recommended to attenuate insulin resistance by shortening the preoperative fasting interval. The aim of our study the effect of preoperative oral administration of CRLDs on the well-being and clinical status of patients. Methods A randomized, double blind, prospective study of patients undergoing open colorectal operations (CR) and open cholecyctectomy (CH) was conducted. Patients were divided into three groups: study, placebo, and ...

  18. Systematic review and meta-analysis of dietary carbohydrate restriction in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Snorgaard, Ole; Poulsen, Grith Møller; Andersen, Henning K

    2017-01-01

    Objective: Nutrition therapy is an integral part of selfmanagement education in patients with type 2 diabetes. Carbohydrates with a low glycemic index are recommended, but the ideal amount of carbohydrate in the diet is unclear. We performed a meta-analysis comparing diets containing low...... to moderate amounts of carbohydrate (LCD) (energy percentage below 45%) to diets containing high amounts of carbohydrate (HCD) in subjects with type 2 diabetes. Research design and methods: We systematically reviewed Cochrane library databases, EMBASE, and MEDLINE in the period 2004–2014 for guidelines, meta...... to moderate carbohydrate diets have greater effect on glycemic control in type 2 diabetes compared with high-carbohydrate diets in the first year of intervention. The greater the carbohydrate restriction, the greater glucose lowering, a relationship that has not been demonstrated earlier. Apart from...

  19. Structures of W(2.2 Lie conformal algebra

    Directory of Open Access Journals (Sweden)

    Yuan Lamei

    2016-01-01

    . In this paper, we study conformal derivations, central extensions and conformal modules for this Lie conformal algebra. Also, we compute the cohomology of this Lie conformal algebra with coefficients in its modules. In particular, we determine its cohomology with trivial coefficients both for the basic and reduced complexes.

  20. Warped products and conformal boundaries of CAT(0)-Spaces

    DEFF Research Database (Denmark)

    Buckley, S.M.; Kokkendorff, Simon Lyngby

    2008-01-01

    We discuss the conformal boundary of a warped product of two length spaces and provide a method to calculate this in terms of the individual conformal boundaries. This technique is then applied to produce CAT(0)-spaces with complicated conformal boundaries. Finally, we prove that the conformal...