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Sample records for branched chain alpha-oxo

  1. Radiolabeled dimethyl branched long chain fatty acid for heart imaging

    Science.gov (United States)

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

    1988-08-16

    A radiolabeled long chain fatty acid for heart imaging that has dimethyl branching at one of the carbons of the chain which inhibits the extent to which oxidation can occur. The closer to the carboxyl the branching is positioned, the more limited the oxidation, thereby resulting in prolonged retention of the radiolabeled compound in the heart.

  2. Role of mitochondrial transamination in branched chain amino acid metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Hutson, S.M.; Fenstermacher, D.; Mahar, C.

    1988-03-15

    Oxidative decarboxylation and transamination of 1-/sup 14/C-branched chain amino and alpha-keto acids were examined in mitochondria isolated from rat heart. Transamination was inhibited by aminooxyacetate, but not by L-cycloserine. At equimolar concentrations of alpha-ketoiso(1-/sup 14/C)valerate (KIV) and isoleucine, transamination was increased by disrupting the mitochondria with detergent which suggests transport may be one factor affecting the rate of transamination. Next, the subcellular distribution of the aminotransferase(s) was determined. Branched chain aminotransferase activity was measured using two concentrations of isoleucine as amino donor and (1-/sup 14/C)KIV as amino acceptor. The data show that branched chain aminotransferase activity is located exclusively in the mitochondria in rat heart. Metabolism of extramitochondrial branched chain alpha-keto acids was examined using 20 microM (1-/sup 14/C)KIV and alpha-ketoiso(1-/sup 14/C)caproate (KIC). There was rapid uptake and oxidation of labeled branched chain alpha-keto acid, and, regardless of the experimental condition, greater than 90% of the labeled keto acid substrate was metabolized during the 20-min incubation. When a branched chain amino acid (200 microM) or glutamate (5 mM) was present, 30-40% of the labeled keto acid was transaminated while the remainder was oxidized. Provision of an alternate amino acceptor in the form of alpha-keto-glutarate (0.5 mM) decreased transamination of the labeled KIV or KIC and increased oxidation. Metabolism of intramitochondrially generated branched chain alpha-keto acids was studied using (1-/sup 14/C)leucine and (1-/sup 14/C)valine. Essentially all of the labeled branched chain alpha-keto acid produced by transamination of (1-/sup 14/C)leucine or (1-/sup 14/C)valine with a low concentration of unlabeled branched chain alpha-keto acid (20 microM) was oxidized.

  3. Infinitely dimensional control Markov branching chains in random environments

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    First of all we introduce the concepts of infinitely dimensional control Markov branching chains in random environments (β-MBCRE) and prove the existence of such chains, then we introduce the concepts of conditional generating functionals and random Markov transition functions of such chains and investigate their branching property. Base on these concepts we calculate the moments of the β-MBCRE and obtain the main results of this paper such as extinction probabilities, polarization and proliferation rate. Finally we discuss the classification ofβ-MBCRE according to the different standards.

  4. Branched-chain 2-keto acid decarboxylases derived from Psychrobacter.

    Science.gov (United States)

    Wei, Jiashi; Timler, Jacobe G; Knutson, Carolann M; Barney, Brett M

    2013-09-01

    The conversion of branched-chain amino acids to branched-chain acids or alcohols is an important aspect of flavor in the food industry and is dependent on the Ehrlich pathway found in certain lactic acid bacteria. A key enzyme in the pathway, the 2-keto acid decarboxylase (KDC), is also of interest in biotechnology applications to produce small branched-chain alcohols that might serve as improved biofuels or other commodity feedstocks. This enzyme has been extensively studied in the model bacterium Lactococcus lactis, but is also found in other bacteria and higher organisms. In this report, distinct homologs of the L. lactis KDC originally annotated as pyruvate decarboxylases from Psychrobacter cryohalolentis K5 and P. arcticus 273-4 were cloned and characterized, confirming a related activity toward specific branched-chain 2-keto acids derived from branched-chain amino acids. Further, KDC activity was confirmed in intact cells and cell-free extracts of P. cryohalolentis K5 grown on both rich and defined media, indicating that the Ehrlich pathway may also be utilized in some psychrotrophs and psychrophiles. A comparison of the similarities and differences in the P. cryohalolentis K5 and P. arcticus 273-4 KDC activities to other bacterial KDCs is presented. PMID:23826991

  5. Uptake of Branched-Chain Amino Acids by Streptococcus thermophilus

    OpenAIRE

    Akpemado, K. M.; Bracquart, P. A.

    1983-01-01

    The transport of branched-chain amino acids in Streptococcus thermophilus was energy dependent. The metabolic inhibitors of glycolysis and ATPase enzymes were active, but the proton-conducting uncouplers were not. Transport was optimal at temperatures of between 30 and 45°C and at pH 7.0 for the three amino acids leucine, valine, and isoleucine; a second peak existed at pH 5.0 with valine and isoleucine. By competition and kinetics studies, the branched-chain amino acids were found to share a...

  6. THE EXISTENCE AND MOMENTS OF CANONICAL BRANCHING CHAIN IN RANDOM ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    胡迪鹤

    2004-01-01

    The concepts of branching chain in random environmnet and canonical branching chain in random environment axe introduced. Moreover the existence of these chains is proved. Finally the exact formulas of mathematical expectation and variance of branching chain in random environment axe also given.

  7. Additional chain-branching pathways in the low-temperature oxidation of branched alkanes

    KAUST Repository

    Wang, Zhandong

    2015-12-31

    Chain-branching reactions represent a general motif in chemistry, encountered in atmospheric chemistry, combustion, polymerization, and photochemistry; the nature and amount of radicals generated by chain-branching are decisive for the reaction progress, its energy signature, and the time towards its completion. In this study, experimental evidence for two new types of chain-branching reactions is presented, based upon detection of highly oxidized multifunctional molecules (HOM) formed during the gas-phase low-temperature oxidation of a branched alkane under conditions relevant to combustion. The oxidation of 2,5-dimethylhexane (DMH) in a jet-stirred reactor (JSR) was studied using synchrotron vacuum ultra-violet photoionization molecular beam mass spectrometry (SVUV-PI-MBMS). Specifically, species with four and five oxygen atoms were probed, having molecular formulas of C8H14O4 (e.g., diketo-hydroperoxide/keto-hydroperoxy cyclic ether) and C8H16O5 (e.g., keto-dihydroperoxide/dihydroperoxy cyclic ether), respectively. The formation of C8H16O5 species involves alternative isomerization of OOQOOH radicals via intramolecular H-atom migration, followed by third O2 addition, intramolecular isomerization, and OH release; C8H14O4 species are proposed to result from subsequent reactions of C8H16O5 species. The mechanistic pathways involving these species are related to those proposed as a source of low-volatility highly oxygenated species in Earth\\'s troposphere. At the higher temperatures relevant to auto-ignition, they can result in a net increase of hydroxyl radical production, so these are additional radical chain-branching pathways for ignition. The results presented herein extend the conceptual basis of reaction mechanisms used to predict the reaction behavior of ignition, and have implications on atmospheric gas-phase chemistry and the oxidative stability of organic substances. © 2015 The Combustion Institute.

  8. Branched-chain fatty acid biosynthesis in a branched-chain amino acid aminotransferase mutant of Staphylococcus carnosus

    DEFF Research Database (Denmark)

    Beck, Hans Christian

    2005-01-01

    the amino acids valine, isoleucine, and leucine, and required the short branched chain acids 2-methylbutanoic acid or 2-methylpropanoic acid for growth in a defined medium. The isoleucine related metabolites, alpha-keto-beta-methylvaleric acid and 2-methylbutanal also served as growth factors. Growth...... was observed. Despite the deficiency in IlvE activity, the mutant strain was still able to produce the short chain carboxylic acids, 3-methylbutanoic acid and 2-methylpropanoic acid when cultivated in rich medium. Supplementation experiments employing deuterated glucose induced the valine biosynthetic pathway...

  9. The Laplace Functional and Moments for Markov Branching Chains in Random Environments

    Institute of Scientific and Technical Information of China (English)

    HU Di-he; ZHANG Shu-lin

    2005-01-01

    The concepts of random Markov matrix, Markov branching chain in random environment (MBCRE) and Laplace functional of Markov branching chain in random environment (LFMBCRE) are introduced. The properties of LFMBCRE and the explicit formulas of moments of MBCRE are given.

  10. Improved zeolite regeneration processes for preparing saturated branched-chain fatty acids

    Science.gov (United States)

    Ferrierite zeolite solid is an excellent catalyst for the skeletal isomerization of unsaturated linear-chain fatty acids (i.e., oleic acid) to unsaturated branched-chain fatty acids (i.e., iso-oleic acid) follow by hydrogenation to give saturated branched-chain fatty acids (i.e., isostearic acid). ...

  11. Catabolism of Branched Chain Amino Acids Supports Respiration but Not Volatile Synthesis in Tomato Fruits

    Institute of Scientific and Technical Information of China (English)

    Andrej Kochevenko; Wagner L.Araújo; Gregory S.Maloney; Denise M.Tieman; Phuc Thi Do; Mark G.Taylor; Harry J.Klee; Alisdair R.Fernie

    2012-01-01

    The branched-chain amino acid transaminases (BCATs) have a crucial role in metabolism of the branched-chain amino acids leucine,isoleucine,and valine.These enzymes catalyze the last step of synthesis and the initial step of degradation of these amino acids.Although the biosynthetic pathways of branched chain amino acids in plants have been extensively investigated and a number of genes have been characterized,their catabolism in plants is not yet completely understood.We previously characterized the branched chain amino acid transaminase gene family in tomato,revealing both the subcellular localization and kinetic properties of the enzymes encoded by six genes.Here,we examined possible functions of the enzymes during fruit development.We further characterized transgenic plants differing in the expression of branched chain amino acid transaminases 1 and 3,evaluating the rates of respiration in fruits deficient in BCAT1 and the levels of volatiles in lines overexpressing either BCAT1 or BCAT3.We quantitatively tested,via precursor and isotope feeding experiments,the importance of the branched chain amino acids and their corresponding keto acids in the formation of fruit volatiles.Our results not only demonstrate for the first time the importance of branched chain amino acids in fruit respiration,but also reveal that keto acids,rather than amino acids,are the likely precursors for the branched chain flavor volatiles.

  12. Catabolism of leucine to branched-chain fatty acids in Staphylococcus xylosus

    DEFF Research Database (Denmark)

    Beck, Hans Christian; Hansen, A M; Lauritsen, F R

    2004-01-01

    Staphylococcus xylosus is an important starter culture in the production of flavours from the branched-chain amino acids leucine, valine and isoleucine in fermented meat products. The sensorially most important flavour compounds are the branched-chain aldehydes and acids derived from the correspo...... the corresponding amino acids and this paper intends to perspectivate these flavour compounds in the context of leucine metabolism....

  13. Branched-chain amino acids and brain function.

    Science.gov (United States)

    Fernstrom, John D

    2005-06-01

    Branched-chain amino acids (BCAAs) influence brain function by modifying large, neutral amino acid (LNAA) transport at the blood-brain barrier. Transport is shared by several LNAAs, notably the BCAAs and the aromatic amino acids (ArAAs), and is competitive. Consequently, when plasma BCAA concentrations rise, which can occur in response to food ingestion or BCAA administration, or with the onset of certain metabolic diseases (e.g., uncontrolled diabetes), brain BCAA concentrations rise, and ArAA concentrations decline. Such effects occur acutely and chronically. Such reductions in brain ArAA concentrations have functional consequences: biochemically, they reduce the synthesis and the release of neurotransmitters derived from ArAAs, notably serotonin (from tryptophan) and catecholamines (from tyrosine and phenylalanine). The functional effects of such neurochemical changes include altered hormonal function, blood pressure, and affective state. Although the BCAAs thus have biochemical and functional effects in the brain, few attempts have been made to characterize time-course or dose-response relations for such effects. And, no studies have attempted to identify levels of BCAA intake that might produce adverse effects on the brain. The only "model" of very high BCAA exposure is a very rare genetic disorder, maple syrup urine disease, a feature of which is substantial brain dysfunction but that probably cannot serve as a useful model for excessive BCAA intake by normal individuals. Given the known biochemical and functional effects of the BCAAs, it should be a straightforward exercise to design studies to assess dose-response relations for biochemical and functional effects and, in this context, to explore for adverse effect thresholds. PMID:15930466

  14. THE CONSTRUCTION OF MULTITYPE CANONICAL MARKOV BRANCHING CHAINS IN RANDOM ENVIRONMENTS

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The investigation for branching processes has a long history by their strong physics background, but only a few authors have investigated the branching processes in random environments. First of all, the author introduces the concepts of the multitype canonical Markov branching chain in random environment (CMBCRE) and multitype Markov branching chain in random environment (MBCRE) and proved that CMBCRE must be MBCRE, and any MBCRE must be equivalent to another CMBCRE in distribution. The main results of this article are the construction of CMBCRE and some of its probability properties.

  15. Vibration Reduction of Open-chain Flexible Manipulators by Optimizing Independent Motions of Branch Links

    Institute of Scientific and Technical Information of China (English)

    Bian Yushu; Gao Zhihui; Yun Chao

    2008-01-01

    In order to suppress vibration in flexible manipulators, a new type of manipulator mechanism with controllable local degrees of freedom is proposed. This mechanism consists of a main chain and some branch links. The main chain is of a flexible open-chain configuration with an end-effector installed at its tip, and the rigid branch links are able to perform active movements. It is proved by kinematics and dynamic analysis that, the branch links bear no direct kinematic relation to the main chain, but their independent motions can strongly affect the dynamic behavior and performance of the flexible manipulator. Then comes a new idea of suppressing vibration, in which independent motions of the branch links are used to suppress the undesired vibration of the flexible main chain through dynamic coupling. On this basis, an optimal method for reducing vibration of flexible manipulators is proposed. Finally, the effectiveness of this method is verified by numerical simulations.

  16. Bounds of Deviation for Branching Chains in Random Environments

    Institute of Scientific and Technical Information of China (English)

    Wei Gang WANG

    2011-01-01

    We consider non-extinct branching processes in general random environments. Under the condition of means and second moments of each generation being bounded, we give the upper bounds and lower bounds for some form deviations of the process.

  17. Branched-chain amino acids for hepatic encephalopathy. Protocol for Cochrane Review

    DEFF Research Database (Denmark)

    Gluud, C; Koretz, RL

    2000-01-01

    Hepatic encephalopathy may be caused by a decreased plasma ratio of branched-chain amino acids (BCAA) to aromatic amino acids. Treatment with BCAA may therefore have a beneficial effect on patients with hepatic encephalopathy.......Hepatic encephalopathy may be caused by a decreased plasma ratio of branched-chain amino acids (BCAA) to aromatic amino acids. Treatment with BCAA may therefore have a beneficial effect on patients with hepatic encephalopathy....

  18. [Odd- and branched-chain fatty acids in milk fat--characteristic and health properties].

    Science.gov (United States)

    Adamska, Agata; Rutkowska, Jarosława

    2014-01-01

    This review analyzes the current state of knowledge on odd- and branched-chain fatty acids present in milk fat. Special attention is devoted to the characteristic, synthesis in ruminants, factors affecting their content in milk fat and pro-health properties of these compounds. The group of odd- and branched-chain fatty acids includes mainly saturated fatty acids with one or more methyl branches in the iso or anteiso position. These fatty acids are largely derived from ruminal bacteria and they have been transferred to ruminant tissue (milk and meat). For that reason they have been used as biomarkers of rumen fermentation. Odd- and branched-chain fatty acids are exogenous products for humans, and therefore have specific properties. The results of research from recent decades show that odd- and branched-chain fatty acids have anti-cancer activity. Branched-chain fatty acids may reduce the incidence of necrotizing enterocolitis. Additionally, these compounds have a beneficial effect on proper tissue function and on functioning and development of the infant gut, whereas odd-chain fatty acids are considered as biomarkers of milk fat intake by humans. So far, not all the mechanisms of activity of these compounds are known thoroughly. They should be more carefully studied for application of their biological effects in prevention and treatment. PMID:25228507

  19. Diketopyrrolopyrrole-based Conjugated Polymers Bearing Branched Oligo(Ethylene Glycol) Side Chains for Photovoltaic Devices.

    Science.gov (United States)

    Chen, Xingxing; Zhang, Zijian; Ding, Zicheng; Liu, Jun; Wang, Lixiang

    2016-08-22

    Conjugated polymers are essential for solution-processable organic opto-electronic devices. In contrast to the great efforts on developing new conjugated polymer backbones, research on developing side chains is rare. Herein, we report branched oligo(ethylene glycol) (OEG) as side chains of conjugated polymers. Compared with typical alkyl side chains, branched OEG side chains endowed the resulting conjugated polymers with a smaller π-π stacking distance, higher hole mobility, smaller optical band gap, higher dielectric constant, and larger surface energy. Moreover, the conjugated polymers with branched OEG side chains exhibited outstanding photovoltaic performance in polymer solar cells. A power conversion efficiency of 5.37 % with near-infrared photoresponse was demonstrated and the device performance could be insensitive to the active layer thickness.

  20. Mean span dimensions of ideal polymer chains containing branches and rings

    DEFF Research Database (Denmark)

    Wang, Yanwei; Teraoka, Iwao; Hansen, Flemming Yssing;

    2011-01-01

    We present a general method for calculating the mean span dimension of various branched and ringed polymers under the assumption of Gaussian chain statistics. The method allows a routine construction of an integral expression of the mean span dimension based on three base functions, determined...... for a connector, an arm and a loop, respectively. Applications of our method are shown to a variety of polymer architectures including star, two-branch-point, comb and various cyclic chains (eight-shaped, θ-shaped and several semicyclic chains). Comparing the mean span dimension with other commonly used molecular...

  1. Measuring chain digitisation maturity: An assessment of Dutch retail branches

    NARCIS (Netherlands)

    Plomp, M.G.A.; Batenburg, R.S.

    2010-01-01

    Purpose – The purpose of this article is to develop a validated measurement model and typology for chain digitisation maturity, defined as the degree of interorganisational collaboration through ICT. Design/methodology/approach – Through a literature (meta) study, 22 existing maturity models are fou

  2. Measuring chain digitisation maturity: an assessment of Dutch retail branches.

    NARCIS (Netherlands)

    Plomp, M.G.A.; Batenburg, R.S.

    2010-01-01

    The purpose of this article is to develop a validated measurement model and typology for chain digitisation maturity, defined as the degree of interorganisational collaboration through ICT. The advantages of interorganisational information systems (IOIS) seem to meet the challenges currently facing

  3. Communication: Role of short chain branching in polymer structure and dynamics

    Science.gov (United States)

    Kim, Jun Mo; Baig, Chunggi

    2016-02-01

    A comprehensive understanding of chain-branching effects, essential for establishing general knowledge of the structure-property-phenomenon relationship in polymer science, has not yet been found, due to a critical lack of knowledge on the role of short-chain branches, the effects of which have mostly been neglected in favor of the standard entropic-based concepts of long polymers. Here, we show a significant effect of short-chain branching on the structural and dynamical properties of polymeric materials, and reveal the molecular origins behind the fundamental role of short branches, via atomistic nonequilibrium molecular dynamics and mesoscopic Brownian dynamics by systematically varying the strength of the mobility of short branches. We demonstrate that the fast random Brownian kinetics inherent to short branches plays a key role in governing the overall structure and dynamics of polymers, leading to a compact molecular structure and, under external fields, to a lesser degree of structural deformation of polymer, to a reduced shear-thinning behavior, and to a smaller elastic stress, compared with their linear analogues. Their fast dynamical nature being unaffected by practical flow fields owing to their very short characteristic time scale, short branches would substantially influence (i.e., facilitate) the overall relaxation behavior of polymeric materials under various flowing conditions.

  4. Developmental Defects of Caenorhabditis elegans Lacking Branched-chain α-Ketoacid Dehydrogenase Are Mainly Caused by Monomethyl Branched-chain Fatty Acid Deficiency.

    Science.gov (United States)

    Jia, Fan; Cui, Mingxue; Than, Minh T; Han, Min

    2016-02-01

    Branched-chain α-ketoacid dehydrogenase (BCKDH) catalyzes the critical step in the branched-chain amino acid (BCAA) catabolic pathway and has been the focus of extensive studies. Mutations in the complex disrupt many fundamental metabolic pathways and cause multiple human diseases including maple syrup urine disease (MSUD), autism, and other related neurological disorders. BCKDH may also be required for the synthesis of monomethyl branched-chain fatty acids (mmBCFAs) from BCAAs. The pathology of MSUD has been attributed mainly to BCAA accumulation, but the role of mmBCFA has not been evaluated. Here we show that disrupting BCKDH in Caenorhabditis elegans causes mmBCFA deficiency, in addition to BCAA accumulation. Worms with deficiency in BCKDH function manifest larval arrest and embryonic lethal phenotypes, and mmBCFA supplementation suppressed both without correcting BCAA levels. The majority of developmental defects caused by BCKDH deficiency may thus be attributed to lacking mmBCFAs in worms. Tissue-specific analysis shows that restoration of BCKDH function in multiple tissues can rescue the defects, but is especially effective in neurons. Taken together, we conclude that mmBCFA deficiency is largely responsible for the developmental defects in the worm and conceivably might also be a critical contributor to the pathology of human MSUD.

  5. Oral branched-chain amino acids decrease whole-body proteolysis

    Science.gov (United States)

    Ferrando, A. A.; Williams, B. D.; Stuart, C. A.; Lane, H. W.; Wolfe, R. R.

    1995-01-01

    BACKGROUND: This study reports the effects of ingesting branched-chain amino acids (leucine, valine, and isoleucine) on protein metabolism in four men. METHODS: To calculate leg protein synthesis and breakdown, we used a new model that utilized the infusion of L-[ring-13C6]phenylalanine and the sampling of the leg arterial-venous difference and muscle biopsies. In addition, protein-bound enrichments provided for the direct calculation of muscle fractional synthetic rate. Four control subjects ingested an equivalent amount of essential amino acids (threonine, methionine, and histidine) to discern the effects of branched-chain amino acid nitrogen vs the effects of essential amino acid nitrogen. Each drink also included 50 g of carbohydrate. RESULTS: Consumption of the branched-chain and the essential amino acid solutions produced significant threefold and fourfold elevations in their respective arterial concentrations. Protein synthesis and breakdown were unaffected by branched-chain amino acids, but they increased by 43% (p < .05) and 36% (p < .03), respectively, in the group consuming the essential amino acids. However, net leg balance of phenylalanine was unchanged by either drink. Direct measurement of protein synthesis by tracer incorporation into muscle protein (fractional synthetic rate) revealed no changes within or between drinks. Whole-body phenylalanine flux was significantly suppressed by each solution but to a greater extent by the branched-chain amino acids (15% and 20%, respectively) (p < .001). CONCLUSIONS: These results suggest that branched-chain amino acid ingestion suppresses whole-body proteolysis in tissues other than skeletal muscle in normal men.

  6. Physiological covalent regulation of rat liver branched-chain alpha-ketoacid dehydrogenase

    International Nuclear Information System (INIS)

    A radiochemical assay was developed for measuring branched-chain alpha-ketoacid dehydrogenase activity of Triton X-100 extracts of freeze-clamped rat liver. The proportion of active (dephosphorylated) enzyme was determined by measuring enzyme activities before and after activation of the complex with a broad-specificity phosphoprotein phosphatase. Hepatic branched-chain alpha-ketoacid dehydrogenase activity in normal male Wistar rats was 97% active but decreased to 33% active after 2 days on low-protein (8%) diet and to 13% active after 4 days on the same diet. Restricting protein intake of lean and obese female Zucker rats also caused inactivation of hepatic branched-chain alpha-ketoacid dehydrogenase complex. Essentially all of the enzyme was in the active state in rats maintained for 14 days on either 30 or 50% protein diets. This was also the case for rats maintained on a commercial chow diet (minimum 23% protein). However, maintaining rats on 20, 8, and 0% protein diets decreased the percentage of the active form of the enzyme to 58, 10, and 7% of the total, respectively. Fasting of chow-fed rats for 48 h had no effect on the activity state of hepatic branched-chain alpha-ketoacid dehydrogenase, i.e., 93% of the enzyme remained in the active state compared to 97% for chow-fed rats. However, hepatic enzyme of rats maintained on 8% protein diet was 10% active before starvation and 83% active after 2 days of starvation. Thus, dietary protein deficiency results in inactivation of hepatic branched-chain alpha-ketoacid dehydrogenase complex, presumably as a consequence of low hepatic levels of branched-chain alpha-ketoacids

  7. Mathematical Modeling of the Process for Microbial Production of Branched Chained Amino Acids

    Directory of Open Access Journals (Sweden)

    Todorov K.

    2009-12-01

    Full Text Available This article deals with modelling of branched chained amino acids production. One of important branched chained amino acid is L-valine. The aim of the article is synthesis of dynamic unstructured model of fed-batch fermentation process with intensive droppings for L-valine production. The presented approach of the investigation includes the following main procedures: description of the process by generalized stoichiometric equations; preliminary data processing and calculation of specific rates for main kinetic variables; identification of the specific rates takes into account the dissolved oxygen tension; establishment and optimisation of dynamic model of the process; simulation researches. MATLAB is used as a research environment.

  8. Proteomic analysis of plasma after branched chain enriched mixture supplementation in mice

    OpenAIRE

    Brocca, Lorenza; Mascaro, Anna; D’Antona, Giuseppe

    2013-01-01

    Background Branched chain amino acid (BCAA) supplementation is a recently identified strategy to promote longevity in mice. A proteomic approach was used to identify proteins which are differentially expressed in the sera of mice following supplementation with selected branched chain amino acid enriched mixture (BCAAem). Findings 12 male mice (C57Bl6, 9 months-old) were randomly assigned to unsupplemented (Control, n = 6) and supplemented (BCAA, n = 6, 0.1 mg/gr/day in drink water for 4 weeks...

  9. Electron beam curable branched chain polyurethane acrylates for magnetic media coatings

    International Nuclear Information System (INIS)

    Electron beam curable binder resins have been studied to realize the high quality magnetic coatings. It was supposed that resins with a higher crosslink density could lead to magnetic coatings with higher abrasion resistance. Branched chain polyurethane acrylates show a higher degree of cure by irradiation with an electron beam in comparison with linear polyurethane acrylates. This paper describes the potential wear resistance between properties of magnetic coatings and the physical properties of the cured unpigmented branched chain polyurethane acrylates that were used as the binder resins. (author)

  10. High orientation of long chain branched poly (lactic acid) with enhanced blood compatibility and bionic structure.

    Science.gov (United States)

    Li, Zhengqiu; Ye, Lin; Zhao, Xiaowen; Coates, Phil; Caton-Rose, Fin; Martyn, Michasel

    2016-05-01

    Highly oriented poly (lactic acid) (PLA) with bionic microgrooves was fabricated through solid hot drawing technology for further improving the mechanical properties and blood biocompatibility of PLA. In order to enhance the melt strength and thus obtain high orientation degree, long chain branched PLA was prepared at first through a two-step ring-opening reaction during processing. Linear viscoelasticity combined with branch-on-branch model was used to predict probable compositions and chain topologies of the products, and it was found that the molecular weight of PLA increased and topological structures with star like chain with three arms and tree-like chain with two generations formed during reactive processing, and consequently draw ratio as high as1200% can be achieved during the subsequent hot stretching. With the increase of draw ratio, the tensile strength and orientation degree of PLA increased dramatically. Long chain branching and orientation could significantly enhance the blood compatibility of PLA by prolonging clotting time and decreasing platelet activation. Microgrooves can be observed on the surface of the oriented PLA which were similar to the intimal layer of blood vessel, and such bionic structure resulted from the formation of the oriented shish kebab-like crystals along the draw direction.

  11. Searching for low percolation thresholds within amphiphilic polymer membranes: The effect of side chain branching

    Science.gov (United States)

    Dorenbos, G.

    2015-06-01

    Percolation thresholds for solvent diffusion within hydrated model polymeric membranes are derived from dissipative particle dynamics in combination with Monte Carlo (MC) tracer diffusion calculations. The polymer backbones are composed of hydrophobic A beads to which at regular intervals Y-shaped side chains are attached. Each side chain is composed of eight A beads and contains two identical branches that are each terminated with a pendant hydrophilic C bead. Four types of side chains are considered for which the two branches (each represented as [C], [AC], [AAC], or [AAAC]) are splitting off from the 8th, 6th, 4th, or 2nd A bead, respectively. Water diffusion through the phase separated water containing pore networks is deduced from MC tracer diffusion calculations. The percolation threshold for the architectures containing the [C] and [AC] branches is at a water volume fraction of ˜0.07 and 0.08, respectively. These are much lower than those derived earlier for linear architectures of various side chain length and side chain distributions. Control of side chain architecture is thus a very interesting design parameter to decrease the percolation threshold for solvent and proton transports within flexible amphiphilic polymer membranes.

  12. Searching for low percolation thresholds within amphiphilic polymer membranes: The effect of side chain branching

    Energy Technology Data Exchange (ETDEWEB)

    Dorenbos, G., E-mail: dorenbos@ny.thn.ne.jp [Sano 1107-2, Belle Crea 502, Susono 410-1118 (Japan)

    2015-06-14

    Percolation thresholds for solvent diffusion within hydrated model polymeric membranes are derived from dissipative particle dynamics in combination with Monte Carlo (MC) tracer diffusion calculations. The polymer backbones are composed of hydrophobic A beads to which at regular intervals Y-shaped side chains are attached. Each side chain is composed of eight A beads and contains two identical branches that are each terminated with a pendant hydrophilic C bead. Four types of side chains are considered for which the two branches (each represented as [C], [AC], [AAC], or [AAAC]) are splitting off from the 8th, 6th, 4th, or 2nd A bead, respectively. Water diffusion through the phase separated water containing pore networks is deduced from MC tracer diffusion calculations. The percolation threshold for the architectures containing the [C] and [AC] branches is at a water volume fraction of ∼0.07 and 0.08, respectively. These are much lower than those derived earlier for linear architectures of various side chain length and side chain distributions. Control of side chain architecture is thus a very interesting design parameter to decrease the percolation threshold for solvent and proton transports within flexible amphiphilic polymer membranes.

  13. Enzymology of the branched-chain amino acid oxidation disorders: the valine pathway

    OpenAIRE

    Wanders, Ronald J.A.; Duran, Marinus; Loupatty, Ference J.

    2010-01-01

    Valine is one of the three branched-chain amino acids which undergoes oxidation within mitochondria. In this paper, we describe the current state of knowledge with respect to the enzymology of the valine oxidation pathway and the different disorders affecting oxidation.

  14. Enzymology of the branched-chain amino acid oxidation disorders: the valine pathway.

    Science.gov (United States)

    Wanders, Ronald J A; Duran, Marinus; Loupatty, Ference J

    2012-01-01

    Valine is one of the three branched-chain amino acids which undergoes oxidation within mitochondria. In this paper, we describe the current state of knowledge with respect to the enzymology of the valine oxidation pathway and the different disorders affecting oxidation.

  15. Metabolite production and kinetics of branched-chain aldehyde oxidation in Staphylococcus xylosus

    DEFF Research Database (Denmark)

    Beck, Hans Christian; Hansen, A.M.; Lauritsen, F.R.

    2002-01-01

    ,5-methylpyrazine, 2-phenylethylacetate, 2-methyltetrahydrothiophen-3-one, 3-(methylthio)-propanoic acid and 3-(methylthio)-propanal. The organoleptic metabolites derived from branched-chain amino acid catabolism; 2-methylpropanal from valine, 2-methylbutanal from isoleucine and 3-methylbutanal from leucine were...

  16. Effect of Cholesterol on the Branched-Chain Amino Acid Transport System of Streptococcus cremoris

    NARCIS (Netherlands)

    Zheng, Tan; Driessen, Arnold J.M.; Konings, Wilhelmus

    1988-01-01

    The effect of cholesterol on the activity of the branched-chain amino acid transport system of Streptococcus cremoris was studied in membrane vesicles of S. cremoris fused with liposomes made of egg yolk phosphatidylcholine, soybean phosphatidylethanolamine, and various amounts of cholesterol. Chole

  17. Surface Segregation and Bulk Thermodynamics in Blends of Long-Branched and Linear Chains

    Science.gov (United States)

    Martter, T. D.; Foster, M. D.; Xu, S.; Yoo, T.; Quirk, R. P.; Ohno, K.; Haddleton, D. M.; Hawker, C.; Majkrzak, C.; Butler, P.

    2001-03-01

    We have investigated the effect of regular long chain branching on bulk thermodynamics and surface segregation in blends of linear and branched polymers. Polystyrene and low vinyl content polybutadiene polymerized anionically have both been studied. The nonlocal thermodynamic interaction between the chains in the bulk can be characterized by a segment-segment interaction parameter, chi, measured using Small Angle Neutron Scattering. While chi is found to increase monotonically with the number of arms in the star for PS blends, this is not true for PB blends. In the case of the PB blends, isotopic effects play a more important role in determining the segregation behavior than in the case of the PS blends. Some experiments have also been performed to probe the effect of core chemistry on the bulk and surface behavior. Changing the type of long-branched component from star-branched to comb-branched, while the number of arms is kept constant, impacts both the bulk interaction and surface segregation. Acknowledgements: Collaborators were G. Lizzaraga, J. Hwang, C.C. Greenberg, S. Corona-Galvan, and E. Cloutet (Institute of Polymer Science at The University of Akron) and J.D. Demaree (Army Research Lab, AMSRL-WM-ME, APG, MD 21005).

  18. Plasma branched chain amino acid abnormalities in sake-treated rats.

    Directory of Open Access Journals (Sweden)

    Watanabe,Akiharu

    1985-02-01

    Full Text Available Plasma amino acid abnormalities in rats treated with large doses of sake and whisky for 3 days were investigated under adequate nutritional conditions. A significant decrease in plasma branched-chain amino acid (BCAA levels was observed in sake- but not whisky-treated rats. However, known factors affecting BCAA levels, such as serum insulin and plasma glucagon levels ahd BCAA-metabolizing enzyme (BCAA transaminase and branched chain alpha-ketoacid dehydrogenase activities in the liver and skeletal muscle, were not significantly altered in the sake group. Furthermore, ethanol-metabolizing enzyme (alcohol and aldehyde dehydrogenases and the microsomal ethanol-oxidizing system activities in the liver were not altered in the sake group. Other mechanisms need to be considered for explaining the diminished levels of plasma BCAA in sake-treated rats.

  19. Branched-Chain Aminotransferases Control TORC1 Signaling in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Joanne M Kingsbury

    2015-12-01

    Full Text Available The conserved target of rapamycin complex 1 (TORC1 integrates nutrient signals to orchestrate cell growth and proliferation. Leucine availability is conveyed to control TORC1 activity via the leu-tRNA synthetase/EGOC-GTPase module in yeast and mammals, but the mechanisms sensing leucine remain only partially understood. We show here that both leucine and its α-ketoacid metabolite, α-ketoisocaproate, effectively activate the yeast TORC1 kinase via both EGOC GTPase-dependent and -independent mechanisms. Leucine and α-ketoisocaproate are interconverted by ubiquitous branched-chain aminotransferases (BCAT, which in yeast are represented by the mitochondrial and cytosolic enzymes Bat1 and Bat2, respectively. BCAT yeast mutants exhibit severely compromised TORC1 activity, which is partially restored by expression of Bat1 active site mutants, implicating both catalytic and structural roles of BCATs in TORC1 control. We find that Bat1 interacts with branched-chain amino acid metabolic enzymes and, in a leucine-dependent fashion, with the tricarboxylic acid (TCA-cycle enzyme aconitase. BCAT mutation perturbed TCA-cycle intermediate levels, consistent with a TCA-cycle block, and resulted in low ATP levels, activation of AMPK, and TORC1 inhibition. We propose the biosynthetic capacity of BCAT and its role in forming multicomplex metabolons connecting branched-chain amino acids and TCA-cycle metabolism governs TCA-cycle flux to activate TORC1 signaling. Because mammalian mitochondrial BCAT is known to form a supramolecular branched-chain α-keto acid dehydrogenase enzyme complex that links leucine metabolism to the TCA-cycle, these findings establish a precedent for understanding TORC1 signaling in mammals.

  20. Milk Odd- and Branched-Chain Fatty Acids in Relation to the Rumen Fermentation Pattern

    NARCIS (Netherlands)

    Vlaeminck, B.; Fievez, V.; Tamminga, S.; Dewhurst, R.J.; Vuuren, van A.M.; Brabander, de D.; Demeyer, D.

    2006-01-01

    The objectives of this study were 1) to determine whether a relationship exists between molar proportions of volatile fatty acids in the rumen and milk odd-and branched-chain fatty acid concentrations (i.e., iso C13:0, anteiso C13:0, iso C14:0, C15:0, iso C15:0, anteiso C15:0, iso C16:0, C17:0, iso

  1. Internal logistics as a part of supply chain : case : Nokia-China, Dongguang Branch

    OpenAIRE

    Tian, Ran

    2009-01-01

    Internal logistics is one of the most important sections within enterprises, especially in the large manufacturing companies. It manages, arranges, plans and delivers the finished products. It is an indispensable part of the supply chain, as well as reflects the result of implementation company strategy. This study focuses on finding the possible ways to improve the operation process of Nokia-China internal logistics by looking into Nokia-China’s internal logistics in Dongguan Branch- Su...

  2. Chain branching detection by Cole–Cole modeling of rheological properties changes during PET mechanical recycling

    OpenAIRE

    Nait-Ali, K.L; Bergeret, A.; Ferry, L.; Colin, Xavier

    2012-01-01

    International audience; The detection of branched chains in thermally degraded thermoplastic polymers is far from simple, especially at a low conversion ratio, mainly because of the low sensitivity of commonly used laboratory analytical techniques. The objective of this article is to present an approach able to demonstrate the formation of such macromolecular structures during thermal degradation of molten PET at low oxygen partial pressures (typically for pressures lower than 9% of atmospher...

  3. Evolution of the biosynthesis of the branched-chain amino acids

    Science.gov (United States)

    Keefe, Anthony D.; Lazcano, Antonio; Miller, Stanley L.

    1995-06-01

    The origin of the biosynthetic pathways for the branched-chain amino acids cannot be understood in terms of the backwards development of the present acetolactate pathway because it contains unstable intermediates. We propose that the first biosynthesis of the branched-chain amino acids was by the reductive carboxylation of short branched chain fatty acids giving keto acids which were then transaminated. Similar reaction sequences mediated by nonspecific enzymes would produce serine and threonine from the abundant prebiotic compounds glycolic and lactic acids. The aromatic amino acids may also have first been synthesized in this way, e.g. tryptophan from indole acetic acid. The next step would have been the biosynthesis of leucine from α-ketoisovaleric acid. The acetolactate pathway developed subsequently. The first version of the Krebs cycle, which was used for amino acid biosynthesis, would have been assembled by making use of the reductive carboxylation and leucine biosynthesis enzymes, and completed with the development of a single new enzyme, succinate dehydrogenase. This evolutionary scheme suggests that there may be limitations to inferring the origins of metabolism by a simple back extrapolation of current pathways.

  4. Evolution of the biosynthesis of the branched-chain amino acids

    Science.gov (United States)

    Keefe, Anthony D.; Lazcano, Antonio; Miller, Stanley L.

    1995-01-01

    The origins of the biosynthetic pathways for the branched-chain amino acids cannot be understood in terms of the backwards development of the present acetolactate pathway because it contains unstable intermediates. We propose that the first biosynthesis of the branched-chain amino acids was by the reductive carboxylation of short branched chain fatty acids giving keto acids which were then transaminated. Similar reaction sequences mediated by nonspecific enzymes would produce serine and threomine from the abundant prebiotic compounds glycolic and lactic acids. The aromatic amino acids may also have first been synthesized in this way, e.g. tryptophan from indole acetic acid. The next step would have been the biosynthesis of leucine from alpha-ketoisovalerc acid. The acetolactate pathway developed subsequently. The first version of the Krebs cycle, which was used for amino acid biosynthesis, would have been assembled by making use fo the reductive carboxylation and leucine biosynthesis enzymes, and completed with the development of a single new enzyme, succinate dehydrogenase. This evolutionary scheme suggests that there may be limitations to inferring the origins of metabolism by a simple back extrapolation of current pathways.

  5. Metabolism of branched-chain amino acids in leg muscles from tail-cast suspended intact and adrenalectomized rats

    Science.gov (United States)

    Jaspers, Stephen R.; Henriksen, Erik; Jacob, Stephan; Tischler, Marc E.

    1989-01-01

    The effects of muscle unloading, adrenalectomy, and cortisol treatment on the metabolism of branched-chain amino acids in the soleus and extensor digitorum longus of tail-cast suspended rats were investigated using C-14-labeled lucine, isoleucine, and valine in incubation studies. It was found that, compared to not suspended controls, the degradation of branched-chain amino acids in hind limb muscles was accelerated in tail-cast suspended rats. Adrenalectomy was found to abolish the aminotransferase flux and to diminish the dehydrogenase flux in the soleus. The data also suggest that cortisol treatment increases the rate of metabolism of branched-chain amino acids at the dehydrogenase step.

  6. Ultrafast energy transfer from rigid, branched side-chains into a conjugated, alternating copolymer

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Graham B.; Rolczynski, Brian S.; Linkin, Alexander; McGillicuddy, Ryan D.; Engel, Gregory S., E-mail: gsengel@uchicago.edu [Department of Chemistry, The James Franck Institute, Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637 (United States); Lundin, Pamela M. [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States); A. R. Smith Department of Chemistry, Appalachian State University, 417 CAP Building, 525 Rivers Street, Boone, North Carolina 28608 (United States); Bao, Zhenan [Department of Chemical Engineering, Stanford University, Stauffer III, 381 North-South Mall, Stanford, California 94305 (United States)

    2014-01-21

    We present the synthesis and characterization of a benzodithiophene/thiophene alternating copolymer decorated with rigid, singly branched pendant side chains. We characterize exciton migration and recombination dynamics in these molecules in tetrahydrofuran solution, using a combination of static and time-resolved spectroscopies. As control experiments, we also measure electronic relaxation dynamics in isolated molecular analogues of both the side chain and polymer moieties. We employ semi-empirical and time-dependent density functional theory calculations to show that photoexcitation of the decorated copolymer using 395 nm laser pulses results in excited states primarily localized on the pendant side chains. We use ultrafast transient absorption spectroscopy to show that excitations are transferred to the polymer backbone faster than the instrumental response function, ∼250 fs.

  7. Self-assembly of long chain fatty acids: effect of a methyl branch.

    Science.gov (United States)

    Liljeblad, Jonathan F D; Tyrode, Eric; Thormann, Esben; Dublanchet, Ann-Claude; Luengo, Gustavo; Magnus Johnson, C; Rutland, Mark W

    2014-09-01

    The morphology and molecular conformation of Langmuir-Blodgett deposited and floating monolayers of a selection of straight chain (eicosanoic acid, EA), iso (19-methyl eicosanoic acid, 19-MEA), and anteiso (18-methyl eicosanoic acid, 18-MEA) fatty acids have been investigated by Vibrational Sum Frequency Spectroscopy (VSFS), AFM imaging, and the Langmuir trough. While the straight chain fatty acid forms smooth, featureless monolayers, all the branched chain fatty acids display 10-50 nm sized domains (larger for 19-MEA than the 18-MEA) with a homogeneous size distribution. A model is suggested to explain the domain formation and size in terms of the branched fatty acid packing properties and the formation of hemispherical caps at the liquid-air interface. No difference between the chiral (S) form and the racemic mixture of the 18-MEA is observed with any of the utilized techniques. The aliphatic chains of the straight chain fatty acids appear to be oriented perpendicular to the sample surface, based on an orientational analysis of VSFS data and the odd/even effect. In addition, the selection of the subphase (neat water or CdCl2 containing water buffered to pH 6.0) used for the LB-deposition has a profound influence on the monolayer morphology, packing density, compressibility, and conformational order. Finally, the orientation of the 19-MEA dimethyl moiety is estimated, and a strategy for performing an orientational analysis to determine the complete molecular orientation of the aliphatic chains of 19-MEA and 18-MEA is outlined and discussed. PMID:25045762

  8. Catabolism of Branched Chain Amino Acids Contributes Significantly to Synthesis of Odd-Chain and Even-Chain Fatty Acids in 3T3-L1 Adipocytes

    OpenAIRE

    Crown, Scott B.; Nicholas Marze; Antoniewicz, Maciek R

    2015-01-01

    The branched chain amino acids (BCAA) valine, leucine and isoleucine have been implicated in a number of diseases including obesity, insulin resistance, and type 2 diabetes mellitus, although the mechanisms are still poorly understood. Adipose tissue plays an important role in BCAA homeostasis by actively metabolizing circulating BCAA. In this work, we have investigated the link between BCAA catabolism and fatty acid synthesis in 3T3-L1 adipocytes using parallel 13C-labeling experiments, mass...

  9. Conversion of raw lignocellulosic biomass into branched long-chain alkanes through three tandem steps.

    Science.gov (United States)

    Li, Chunrui; Ding, Daqian; Xia, Qineng; Liu, Xiaohui; Wang, Yanqin

    2016-07-01

    Synthesis of branched long-chain alkanes from renewable biomass has attracted intensive interest in recent years, but the feedstock for this synthesis is restricted to platform chemicals. Here, we develop an effective and energy-efficient process to convert raw lignocellulosic biomass (e.g., corncob) into branched diesel-range alkanes through three tandem steps for the first time. Furfural and isopropyl levulinate (LA ester) were prepared from hemicellulose and cellulose fractions of corncob in toluene/water biphasic system with added isopropanol, which was followed by double aldol condensation of furfural with LA ester into C15 oxygenates and the final hydrodeoxygenation of C15 oxygenates into branched long-chain alkanes. The core point of this tandem process is the addition of isopropanol in the first step, which enables the spontaneous transfer of levulinic acid (LA) into the toluene phase in the form of LA ester through esterification, resulting in LA ester co-existing with furfural in the same phase, which is the basis for double aldol condensation in the toluene phase. Moreover, the acidic aqueous phase and toluene can be reused and the residues, including lignin and humins in aqueous phase, can be separated and carbonized to porous carbon materials. PMID:27241180

  10. Purification and characterization of a branched-chain amino acid aminotransferase from Lactobacillus paracasei subsp paracasei CHCC 2115

    DEFF Research Database (Denmark)

    Thage, B.V.; Rattray, F.P.; Laustsen, M.W.;

    2004-01-01

    Purification and characterization of an aminotransferase (AT) specific for the degradation of branched-chain amino acids from Lactobacillus paracasei subsp. paracasei CHCC 2115. Methods and Results: The purification protocol consisted of anion exchange chromatography, affinity chromatography...

  11. PGC-1α-mediated branched-chain amino acid metabolism in the skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Yukino Hatazawa

    Full Text Available Peroxisome proliferator-activated receptor (PPAR γ coactivator 1α (PGC-1α is a coactivator of various nuclear receptors and other transcription factors, which is involved in the regulation of energy metabolism, thermogenesis, and other biological processes that control phenotypic characteristics of various organ systems including skeletal muscle. PGC-1α in skeletal muscle is considered to be involved in contractile protein function, mitochondrial function, metabolic regulation, intracellular signaling, and transcriptional responses. Branched-chain amino acid (BCAA metabolism mainly occurs in skeletal muscle mitochondria, and enzymes related to BCAA metabolism are increased by exercise. Using murine skeletal muscle overexpressing PGC-1α and cultured cells, we investigated whether PGC-1α stimulates BCAA metabolism by increasing the expression of enzymes involved in BCAA metabolism. Transgenic mice overexpressing PGC-1α specifically in the skeletal muscle had increased the expression of branched-chain aminotransferase (BCAT 2, branched-chain α-keto acid dehydrogenase (BCKDH, which catabolize BCAA. The expression of BCKDH kinase (BCKDK, which phosphorylates BCKDH and suppresses its enzymatic activity, was unchanged. The amount of BCAA in the skeletal muscle was significantly decreased in the transgenic mice compared with that in the wild-type mice. The amount of glutamic acid, a metabolite of BCAA catabolism, was increased in the transgenic mice, suggesting the activation of muscle BCAA metabolism by PGC-1α. In C2C12 cells, the overexpression of PGC-1α significantly increased the expression of BCAT2 and BCKDH but not BCKDK. Thus, PGC-1α in the skeletal muscle is considered to significantly contribute to BCAA metabolism.

  12. Purification of a branched-chain keto acid dehydrogenase from Pseudomonas putida.

    OpenAIRE

    Sokatch, J R; McCully, V; Roberts, C M

    1981-01-01

    We purified branched-chain keto acid dehydrogenase to a specific activity of 10 mumol/min per mg of protein from Pseudomonas putida grown on valine. The purified enzyme was active with 2-ketoisovalerate, 2-ketoisocaproate, and 2-keto-3-methylvalerate in a ratio of 1.0:0.8:0.7 but showed no activity with either pyruvate or 2-ketoglutarate. There were four polypeptides in the purified enzyme (molecular weights, 49,000, 46,000, 39,000, and 37,000). The purified enzyme was deficient in the specif...

  13. Role of Branched-Chain Amino Acid Transport in Bacillus subtilis CodY Activity

    OpenAIRE

    Belitsky, Boris R.

    2015-01-01

    CodY is a branched-chain amino acid-responsive transcriptional regulator that controls the expression of several dozen transcription units in Bacillus subtilis. The presence of isoleucine, valine, and leucine in the growth medium is essential for achieving high activity of CodY and for efficient regulation of the target genes. We identified three permeases—BcaP, BraB, and BrnQ—that are responsible for the bulk of isoleucine and valine uptake and are also involved in leucine uptake. At least o...

  14. Instability Criterion of One-Dimensional Detonation Wave with Three-Step Chain Branching Reaction Model

    Institute of Scientific and Technical Information of China (English)

    TENG Hong-Hui; JIANG Zong-Lin

    2011-01-01

    @@ One-dimensional detonation waves are simulated with the three-step chain branching reaction model, and the instability criterion is studied.The ratio of the induction zone length and the reaction zone length may be used to decide the instability, and the detonation becomes unstable with the high ratio.However, the ratio is not invariable with different heat release values.The critical ratio, corresponding to the transition from the stable detonation to the unstable detonation, has a negative correlation with the heat release.An empirical relation of the Chapman-Jouguet Mach number and the length ratio is proposed as the instability criterion.

  15. SOLUTION CRYSTALLIZATION OF METALLOCENE SHORT CHAIN BRANCHED POLYETHYLENE: MORPHOLOGY AND MECHANISM

    Institute of Scientific and Technical Information of China (English)

    Qiang Fu; Rong-ni Du; Fang-Chyou Chiu

    2000-01-01

    Solution crystallization of metallocene short chain branched polyethylene (SCBPE) was carried out and very nice single crystals were obtained. Compared with single crystals grown from linear polyethylene, SCBPE single crystals are dirty due to intermolecular heterogeneity The crystal morphology changes with crystallization temperatures. Lozenge, truncated lozenge, hexagonal, rounded and elongated crystal morphologies have been found at much lower crystallization temperature than in linear polyethylene. The electron diffraction shows there is a possibility that the single crystals may have hexagonal packing in a crystallization temperature range. The lateral habits of single crystal are discussed based on roughening theories.

  16. A safety assessment of branched chain saturated alcohols when used as fragrance ingredients

    DEFF Research Database (Denmark)

    Belsito, D.; Bickers, D.; Bruze, M.;

    2010-01-01

    The Branched Chain Saturated Alcohol (BCSA) group of fragrance ingredients was evaluated for safety. In humans, no evidence of skin irritation was found at concentrations of 2-10%. Undiluted, 11 materials evaluated caused moderate to severe eye irritation. As current end product use levels are...... carcinogenicity study showed that 2-ethyl-1-hexanol is a weak inducer of liver tumors in female mice, however, the relevance of this effect and mode of action to humans is still a matter of debate. The Panel is of the opinion that there are no safety concerns regarding BCSA under the present levels of use and...

  17. Self-assembly of long chain fatty acids: Effect of a methyl branch

    DEFF Research Database (Denmark)

    Liljeblad, Jonathan F. D.; Tyrode, Eric; Thormann, Esben;

    2014-01-01

    to explain the domain formation and size in terms of the branched fatty acid packing properties and the formation of hemispherical caps at the liquid-air interface. No difference between the chiral (S) form and the racemic mixture of the 18-MEA is observed with any of the utilized techniques. The aliphatic...... chains of the straight chain fatty acids appear to be oriented perpendicular to the sample surface, based on an orientational analysis of VSFS data and the odd/even effect. In addition, the selection of the subphase (neat water or CdCl2 containing water buffered to pH 6.0) used for the LB-deposition has...

  18. A pilot, short-term dietary manipulation of branched chain amino acids has modest influence on fasting levels of branched chain amino acids

    Directory of Open Access Journals (Sweden)

    Nicole Landa Cavallaro

    2016-01-01

    Full Text Available Background: Elevated fasting levels of branched chain amino acids (BCAAs: valine, isoleucine, leucine in venous blood are associated with a variety of metabolic impairments, including increased risk of type 2 diabetes (T2D. Fasting BCAA levels are influenced by non-dietary factors. However, it is unknown whether fasting BCAAs can be altered through manipulation of dietary intake alone. Objective: To test whether a specific dietary intervention, using differences in BCAA intake, alters fasting BCAA levels independent of other factors. Design: Five healthy male volunteers underwent 4 days of a low and 4 days of a high BCAA content dietary intervention (ClinicalTrials.gov [NCT02110602]. All food and supplements were provided. Fasting BCAAs were measured from venous blood samples by mass spectrometry at baseline and after each intervention. Results: Diets were isocaloric; contained equal percentages of calories from carbohydrate, fats, and protein; and differed from each other in BCAA content (1.5±0.1 vs. 14.0±0.6 g for valine; 4.5±0.9 g vs. 13.8±0.5 g for isoleucine; 2.1±0.2 g vs. 27.1±1.0 g for leucine; p<0.0001 for all. Fasting valine was significantly lower (p=0.02 and fasting isoleucine and leucine were numerically lower following the low BCAA content vs. the high BCAA content diet levels. The inter-individual response to the dietary interventions was variable and not explained by adherence. Conclusion: Short-term dietary manipulation of BCAA intake led to modest changes in fasting levels of BCAAs. The approach from our pilot study can be expanded to test the metabolic implications of dietary BCAA manipulation.

  19. Metabolic switch during adipogenesis: From branched chain amino acid catabolism to lipid synthesis.

    Science.gov (United States)

    Halama, Anna; Horsch, Marion; Kastenmüller, Gabriele; Möller, Gabriele; Kumar, Pankaj; Prehn, Cornelia; Laumen, Helmut; Hauner, Hans; Hrabĕ de Angelis, Martin; Beckers, Johannes; Suhre, Karsten; Adamski, Jerzy

    2016-01-01

    Fat cell metabolism has an impact on body homeostasis and its proper function. Nevertheless, the knowledge about simultaneous metabolic processes, which occur during adipogenesis and in mature adipocytes, is limited. Identification of key metabolic events associated with fat cell metabolism could be beneficial in the field of novel drug development, drug repurposing, as well as for the discovery of patterns predicting obesity risk. The main objective of our work was to provide comprehensive characterization of metabolic processes occurring during adipogenesis and in mature adipocytes. In order to globally determine crucial metabolic pathways involved in fat cell metabolism, metabolomics and transcriptomics approaches were applied. We observed significantly regulated metabolites correlating with significantly regulated genes at different stages of adipogenesis. We identified the synthesis of phosphatidylcholines, the metabolism of even and odd chain fatty acids, as well as the catabolism of branched chain amino acids (BCAA; leucine, isoleucine and valine) as key regulated pathways. Our further analysis led to identification of an enzymatic switch comprising the enzymes Hmgcs2 (3-hydroxy-3-methylglutaryl-CoA synthase) and Auh (AU RNA binding protein/enoyl-CoA hydratase) which connects leucine degradation with cholesterol synthesis. In addition, propionyl-CoA, a product of isoleucine degradation, was identified as a putative substrate for odd chain fatty acid synthesis. The uncovered crosstalks between BCAA and lipid metabolism during adipogenesis might contribute to the understanding of molecular mechanisms of obesity and have potential implications in obesity prediction. PMID:26408941

  20. Infusion of branched-chain enriched amino acid solution in patients with hepatic encephalopathy.

    Science.gov (United States)

    Freund, H; Dienstag, J; Lehrich, J; Yoshimura, N; Bradford, R R; Rosen, H; Atamian, S; Slemmer, E; Holroyde, J; Fischer, J E

    1982-08-01

    Hospitalized patients with hepatic insufficiency often suffer from severe catabolic states and are in urgent need of nutritional support during their acute illness. Protein intolerence, however, remains a significant problem with respect to the provision of adequate nutrition, either enterally or parenterally. The following report is an anecdotal series of 63 consecutive patients in a large urban hospital treated prospectively with nutritional support using a prototype high branched-chain amino acid solution (FO80) given by technique of total parenteral nutrition by the subclavian or internal jugular route with hypertonic dextrose. Sixty-three patients, of which 42 had chronic liver disease (cirrhosis) with acute decompensation and 17 with acute hepatic injury as well as four with hepatorenal syndrome, are the subject of this report. All required intravenous nutritional support and were either intolerant to commercially available parenteral nutrition solutions or were in hepatic encephalopathy at the time they were initially seen. The cirrhotic patients had been hospitalized for a mean of 14.5 +/- 1.9 days before therapy, had a mean bilirubin of 13 mg/100 ml, and had been in coma for 4.8 +/- 0.7 days despite standard therapy. Patients with acute hepatitis had been in the hospital for 16.2 +/- 4.1 days before therapy, had a mean bilirubin of 25 mg/100 ml, and had been in coma 5.2 +/- 1.6 days before therapy. Routine tests of liver function, blood chemistries, amino acids, EEGs, and complex neurological testing including Reitan trailmaking tests were used in the evaluation of these patients. Up to 120 grams of synthetic amino acid solution with hypertonic dextrose was tolerated in these patients with improvement noted in encephalopathy of at least one grade in 87% of the patients with cirrhosis and 75% of the patients with hepatitis. Nitrogen balance was achieved when 75 to 80 grams of synthetic amino acids were administered. Survival was 45% in the cirrhotic group

  1. Decreased Consumption of Branched-Chain Amino Acids Improves Metabolic Health

    Directory of Open Access Journals (Sweden)

    Luigi Fontana

    2016-07-01

    Full Text Available Protein-restricted (PR, high-carbohydrate diets improve metabolic health in rodents, yet the precise dietary components that are responsible for these effects have not been identified. Furthermore, the applicability of these studies to humans is unclear. Here, we demonstrate in a randomized controlled trial that a moderate PR diet also improves markers of metabolic health in humans. Intriguingly, we find that feeding mice a diet specifically reduced in branched-chain amino acids (BCAAs is sufficient to improve glucose tolerance and body composition equivalently to a PR diet via metabolically distinct pathways. Our results highlight a critical role for dietary quality at the level of amino acids in the maintenance of metabolic health and suggest that diets specifically reduced in BCAAs, or pharmacological interventions in this pathway, may offer a translatable way to achieve many of the metabolic benefits of a PR diet.

  2. A Chiral, Photoluminescent, and Spin-Canted {Cu(I)Re(IV)2}n Branched Chain.

    Science.gov (United States)

    Martínez-Lillo, José; Armentano, Donatella; Fortea-Pérez, Francisco R; Stiriba, Salah-Eddine; De Munno, Giovanni; Lloret, Francesc; Julve, Miguel; Faus, Juan

    2015-05-18

    A new heteroleptic 1D Cu(I)-Re(IV) coordination polymer of the formula {Cu(I)Re(IV)Cl4(μ-Cl)(μ-pyz)[Re(IV)Cl4(μ-bpym)]}n·nMeNO2 (1; pyz = pyrazine, bpym = 2,2'-bipyrimidine) has been prepared through the Cu(I)-mediated self-assembly of two different Re(IV) metalloligands, namely, [ReCl5(pyz)](-) and [ReCl4(bpym)]. 1 consists of chiral branched chains with an overall rack-type architecture displaying photoemission and magnetic ordering. These results constitute a first step toward making new multifunctional magnetic materials based on mixed 3d-5d molecular systems.

  3. Tissue of origin dictates branched-chain amino acid metabolism in mutant Kras-driven cancers.

    Science.gov (United States)

    Mayers, Jared R; Torrence, Margaret E; Danai, Laura V; Papagiannakopoulos, Thales; Davidson, Shawn M; Bauer, Matthew R; Lau, Allison N; Ji, Brian W; Dixit, Purushottam D; Hosios, Aaron M; Muir, Alexander; Chin, Christopher R; Freinkman, Elizaveta; Jacks, Tyler; Wolpin, Brian M; Vitkup, Dennis; Vander Heiden, Matthew G

    2016-09-01

    Tumor genetics guides patient selection for many new therapies, and cell culture studies have demonstrated that specific mutations can promote metabolic phenotypes. However, whether tissue context defines cancer dependence on specific metabolic pathways is unknown. Kras activation and Trp53 deletion in the pancreas or the lung result in pancreatic ductal adenocarinoma (PDAC) or non-small cell lung carcinoma (NSCLC), respectively, but despite the same initiating events, these tumors use branched-chain amino acids (BCAAs) differently. NSCLC tumors incorporate free BCAAs into tissue protein and use BCAAs as a nitrogen source, whereas PDAC tumors have decreased BCAA uptake. These differences are reflected in expression levels of BCAA catabolic enzymes in both mice and humans. Loss of Bcat1 and Bcat2, the enzymes responsible for BCAA use, impairs NSCLC tumor formation, but these enzymes are not required for PDAC tumor formation, arguing that tissue of origin is an important determinant of how cancers satisfy their metabolic requirements. PMID:27609895

  4. Differential redox potential between the human cytosolic and mitochondrial branched-chain aminotransferase

    Institute of Scientific and Technical Information of China (English)

    Steven J. Coles; John T. Hancock; Myra E. Conway

    2012-01-01

    The human branched-chain aminotransferase (hBCAT) isoenzymes are CXXC motif redox sensitive homodimers central to glutamate metabolism in the central nervous system.These proteins respond differently to oxidation by H2O2,NO,and S-glutathionylation,suggesting that the redox potential is distinct between isoenzymes.Using various reduced to oxidized glutathione ratios (GSH:GSSG) to alter the redox environment,we demonstrate that hBCATc (cytosolic) has an overall redox potential that is 30 mV lower than hBCATm (mitochondrial).Furthermore,the CXXC motif of hBCATc was estimated to be 80 mV lower,suggesting that hBCATm is more oxidizing in nature.Western blot analysis revealed close correlations between hBCAT S-glutathionylation and the redox status of the assay environment,offering the hBCAT isoenzymes as novel biomarkers for cytosolic and mitochondrial oxidative stress.

  5. Dynamics of shock induced ignition in Fickett's model with chain-branching kinetics: influence of $\\chi$

    CERN Document Server

    Tang, Justin

    2012-01-01

    The problem of shock induced ignition by a piston is addressed in the framework of Fickett's model for reactive compressible flows, i.e., the reactive form of Burgers' equation. An induction-reaction two-step chain-branching model is used to study the coupling between the energy release and the compressible hydrodynamics occurring during the shock ignition transient leading to a detonation. Owing to the model's simplicity, the ignition and acceleration mechanism is explained using the two families of characteristics admitted by the model. The energy release along the particle paths provides the amplification of forward-travelling pressure waves. These waves pre-compress the medium in the induction layer ahead of the reaction zone, therefore changing the induction delays of successive particles. The variation of the induction delay provides the modulation of the amplification of the forward travelling pressure waves by controlling the residence time of the pressure waves in the reaction zone. A closed form ana...

  6. Molecular and phenotypic characteristics of seven novel mutations causing branched-chain organic acidurias.

    Science.gov (United States)

    Stojiljkovic, M; Klaassen, K; Djordjevic, M; Sarajlija, A; Brasil, S; Kecman, B; Grkovic, S; Kostic, J; Rodriguez-Pombo, P; Desviat, L R; Pavlovic, S; Perez, B

    2016-09-01

    Specific mitochondrial enzymatic deficiencies in the catabolism of branched-chain amino acids cause methylmalonic aciduria (MMA), propionic acidemia (PA) and maple syrup urine disease (MSUD). Disease-causing mutations were identified in nine unrelated branched-chain organic acidurias (BCOA) patients. We detected eight previously described mutations: p.Asn219Tyr, p.Arg369His p.Val553Glyfs*17 in MUT, p.Thr198Serfs*6 in MMAA, p.Ile144_Leu181del in PCCB, p.Gly288Valfs*11, p.Tyr438Asn in BCKDHA and p.Ala137Val in BCKDHB gene. Interestingly, we identified seven novel genetic variants: p.Leu549Pro, p.Glu564*, p.Leu641Pro in MUT, p.Tyr206Cys in PCCB, p.His194Arg, p.Val298Met in BCKDHA and p.Glu286_Met290del in BCKDHB gene. In silico and/or eukaryotic expression studies confirmed pathogenic effect of all novel genetic variants. Aberrant enzymes p.Leu549Pro MUT, p.Leu641Pro MUT and p.Tyr206Cys PCCB did not show residual activity in activity assays. In addition, activity of MUT enzymes was not rescued in the presence of vitamin B12 precursor in vitro which was in accordance with non-responsiveness or partial responsiveness of patients to vitamin B12 therapy. Our study brings the first molecular genetic data and detailed phenotypic characteristics for MMA, PA and MSUD patients for Serbia and the whole South-Eastern European region. Therefore, our study contributes to the better understanding of molecular landscape of BCOA in Europe and to general knowledge on genotype-phenotype correlation for these rare diseases. PMID:26830710

  7. The influence of precultivation parameters on the catabolism of branched-chain amino acids by Staphylococcus xylosus and Staphylococcus carnosus

    DEFF Research Database (Denmark)

    Olesen, Pelle Thonning; Stahnke, Louise Heller

    2003-01-01

    The influence of precultivation. parameters on the ability of Staphylococcus xylosus and Staphylococcus carnosus to convert branched-chain amino acids-leucine, isoleucine and valine-into volatile flavour compounds was investigated using resting cells in a defined reaction medium. The studied...... precultivation parameters were: growth phase, temperature, NaCl concentration and the concentration of leucine, isoleucine and valine (only for S. xylosus). Flavour compounds were sampled by automatic static headspace collection and separated/quantified using gas chromatography/flame ionization detection (GC....../FID).Main catabolic products from degradation of leucine, isoleucine and valine were the flavour intensive branched-chain acids: 2-and 3-methylbutanoic and 2-methylpropanoic acids. The precultivation parameters altered the production of the branched-chain acids significantly, but to various degrees for S. xylosus...

  8. Murine branched chain alpha-ketoacid dehydrogenase kinase; cDNA cloning, tissue distribution, and temporal expression during embryonic development.

    Science.gov (United States)

    Doering, C B; Coursey, C; Spangler, W; Danner, D J

    1998-06-01

    These studies were designed to demonstrate the structural and functional similarity of murine branched chain alpha-ketoacid dehydrogenase and its regulation by the complex-specific kinase. Nucleotide sequence and deduced amino acid sequence for the kinase cDNA demonstrate a highly conserved coding sequence between mouse and human. Tissue-specific expression in adult mice parallels that reported in other mammals. Kinase expression in female liver is influenced by circadian rhythm. Of special interest is the fluctuating expression of this kinase during embryonic development against the continuing increase in the catalytic subunits of this mitochondrial complex during development. The need for regulation of the branched chain alpha-ketoacid dehydrogenase complex by kinase expression during embryogenesis is not understood. However, the similarity of murine branched chain alpha-ketoacid dehydrogenase and its kinase to the human enzyme supports the use of this animal as a model for the human system. PMID:9611264

  9. Stereoselective synthesis of 2,2-bis(C-branched-chain) glucopyranosid-3-ulose via autoxidation reaction

    Institute of Scientific and Technical Information of China (English)

    LIU Hong-Min; ZHANG Fuyi; TAO Jing-Chao

    2004-01-01

    Many different approaches for synthesis of branched chain sugars have beenestablished,1 because they are very useful intermediates for synthesis of other non-sugar chiralmolecules, and usually occur in nature. Branched chain glycosidulose can be used for construction offive- and six-membered carbocyclic rings to which two chiral carbons of sugar are incorporated byintramolecular aldol condensation and Robinson annulation,2 Therefore they are useful in thesynthesis of natural products which consist of annulated carbohydrates or where a highlyfunctionalised enantiomerically pure cyclopentane or cyclohexane is required. Also, this type ofbranched chain sugar can be considered as the synthons of monoterpenoid natural products of theiridoid class which have the cyclopentan-(c)-pyran structure. In view of the importance of branchedchain glycosiduloses, it is desirable to have a general, convenient methodology to their synthesis.However, none of the literature methods was reported on their synthesis by a nuclephilic addition toa partially protected glycosidulose, due to the fact that these glycosiduloses are very difficult tosynthesize selectively and unstable;3 and what is more, one-step synthesis branched chainglycosidulose using this method is almost impossible.In this paper, we report on a general, convenient method for stereoselective syntheses of2,2-bis(C-branched-chain)glucopyranosid-3-uloses by the new reaction of 1 with various activemethylene compounds. The generality of this method was examined in detail. The optimumtemperature was 18-25℃. The solvent DMF was better than the others. In all cases he yields werehigher than 60%.All the 2,2-bis(C-branched-chain)glucopyranosid-3-uloses were characterized by X-raycrystallographic analyses. In addition, the important iintermediate in this reaction was isolated,which is the product of autoxidation of 1 at C-3 position. Thus the reaction mechanism for thesynthesis of 2,2-bis(C-branched-chain) glucopyranosid-3-uloses

  10. Branched-chain amino acid catabolism fuels adipocyte differentiation and lipogenesis.

    Science.gov (United States)

    Green, Courtney R; Wallace, Martina; Divakaruni, Ajit S; Phillips, Susan A; Murphy, Anne N; Ciaraldi, Theodore P; Metallo, Christian M

    2016-01-01

    Adipose tissue plays important roles in regulating carbohydrate and lipid homeostasis, but less is known about the regulation of amino acid metabolism in adipocytes. Here we applied isotope tracing to pre-adipocytes and differentiated adipocytes to quantify the contributions of different substrates to tricarboxylic acid (TCA) metabolism and lipogenesis. In contrast to proliferating cells, which use glucose and glutamine for acetyl-coenzyme A (AcCoA) generation, differentiated adipocytes showed increased branched-chain amino acid (BCAA) catabolic flux such that leucine and isoleucine from medium and/or from protein catabolism accounted for as much as 30% of lipogenic AcCoA pools. Medium cobalamin deficiency caused methylmalonic acid accumulation and odd-chain fatty acid synthesis. Vitamin B12 supplementation reduced these metabolites and altered the balance of substrates entering mitochondria. Finally, inhibition of BCAA catabolism compromised adipogenesis. These results quantitatively highlight the contribution of BCAAs to adipocyte metabolism and suggest that BCAA catabolism has a functional role in adipocyte differentiation. PMID:26571352

  11. Effect of branched-chain amino acid supplementation on the oxidized/reduced state of plasma albumin in rats with chronic liver disease

    OpenAIRE

    Kuwahata, Masashi; Kubota, Hiroyo; Katsukawa, Misaki; Ito, Shunsuke; Ogawa, Aki; Kobayashi, Yukiko; Nakamura, Yasushi; Kido, Yasuhiro

    2011-01-01

    We examined whether continuous supplementation with branched-chain amino acids phosphorylates ribosomal protein S6, a downstream effector of mammalian target of rapamycin, and improves hypoalbuminemia of rats with chronic liver disease. Sprague-Dawley rats were fed a casein diet (control group) or a branched-chain amino acid-supplemented casein diet (branched-chain amino acid group) for 11 weeks with repeated injections of carbon tetrachloride. Throughout this experimental period, no signific...

  12. Effects of glucose, glucose plus branched-chain amino acids, or placebo on bike performance over 100 km

    DEFF Research Database (Denmark)

    Madsen, Klavs; MacLean, David A; Kiens, Bente;

    1996-01-01

    This study was undertaken to determine the effects of ingesting either glucose (trial G) or glucose plus branched-chain amino acids (BCAA: trial B), compared with placebo (trial P), during prolonged exercise. Nine well-trained cyclists with a maximal oxygen uptake of 63.1 +/- 1.5 ml O2. min-1.kg-...

  13. Structural determination of ethylene-propylene-diene rubber (EPDM) containing high degree of controlled long-chain branching

    DEFF Research Database (Denmark)

    Mitra, Susanta; Jørgensen, Mikkel; Pedersen, Walther Batsberg;

    2009-01-01

    This work highlights an attempt to characterize the degree and nature of long-chain branching (LCB) in an unknown sample of ethylene-propylene-diene rubber (EPDM). Two EPDM rubbers selected for this study were comparable in comonomer compositions but significantly different with respect to molar ...

  14. Regional myocardial extraction of a radioiodinated branched chain fatty acid during right ventricular pressure overload due to acute pulmonary hypertension

    International Nuclear Information System (INIS)

    To determine whether branched chain fatty acid extraction is reduced during right ventricular (RV) dysfunction due to acute pulmonary artery hypertension, studies were done in 6 anesthetized dogs. Regional branched chain fatty acid extraction was measured by comparing the myocardial uptake of I-125 labeled 15-[p-(iodophenyl)]-3-methylpentadecanoic acid (I-PDA) to myocardial blood flow. Acute pulmonary hypertension was induced by incremental intravenous injection of 100 micron diameter glass beads into six pentobarbital anesthetized, mechanically ventilated dogs. Myocardial blood flow was measured by radiolabeled microspheres both under baseline conditions and during pulmonary hypertension. Mean RV pressure rose from 12 +- 2 (mean +- SEM) to 30 +-3mmHg resulting in a 225 +- 16% increase in RV stroke work. RV ejection fraction, as assessed by gated blood pool scans fell from 39 +- 2 to 18 +- 2%. Left ventricular (LV) pressures, stroke work and ejection fraction were unchanged. Myocardial blood flow increased 132 + 59% in the RV free wall and 67 +- 22% in the RV septum. LV blood flow was unchanged. Despite increased RV work and myocardial blood flow, no differences were noted in the branched chain fatty acid extraction ratios among LV or RV free walls or septum. The authors conclude that early RV dysfunction associated with pulmonary artery hypertension is not due to inadequate myocardial blood flow or branched chain fatty acid extraction

  15. Production of C4 and C5 branched-chain alcohols by engineered Escherichia. coli.

    Science.gov (United States)

    Chen, Xiaoyan; Xu, Jingliang; Yang, Liu; Yuan, Zhenhong; Xiao, Shiyuan; Zhang, Yu; Liang, Cuiyi; He, Minchao; Guo, Ying

    2015-11-01

    Higher alcohols, longer chain alcohols, contain more than 3 carbon atoms, showed close energy advantages as gasoline, and were considered as the next generation substitution for chemical fuels. Higher alcohol biosynthesis by native microorganisms mainly needs gene expression of heterologous keto acid decarboxylase and alcohol dehydrogenases. In the present study, branched-chain α-keto acid decarboxylase gene from Lactococcus lactis subsp. lactis CICC 6246 (Kivd) and alcohol dehydrogenases gene from Zymomonas mobilis CICC 41465 (AdhB) were transformed into Escherichia coli for higher alcohol production. SDS-PAGE results showed these two proteins were expressed in the recombinant strains. The resulting strain was incubated in LB medium at 37 °C in Erlenmeyer flasks and much more 3-methyl-1-butanol (104 mg/L) than isobutanol (24 mg/L) was produced. However, in 5 g/L glucose-containing medium, the production of two alcohols was similar, 156 and 161 mg/L for C4 (isobutanol) and C5 (3-methyl-1-butanol) alcohol, respectively. Effects of fermentation factors including temperature, glucose content, and α-keto acid on alcohol production were also investigated. The increase of glucose content and the adding of α-keto acids facilitated the production of C4 and C5 alcohols. The enzyme activities of pure Kivd on α-ketoisovalerate and α-ketoisocaproate were 26.77 and 21.24 μmol min(-1) mg(-1), respectively. Due to its ability on decarboxylation of α-ketoisovalerate and α-ketoisocaproate, the recombinant E. coli strain showed potential application on isoamyl alcohol and isobutanol production.

  16. Catabolism of Branched Chain Amino Acids Contributes Significantly to Synthesis of Odd-Chain and Even-Chain Fatty Acids in 3T3-L1 Adipocytes.

    Directory of Open Access Journals (Sweden)

    Scott B Crown

    Full Text Available The branched chain amino acids (BCAA valine, leucine and isoleucine have been implicated in a number of diseases including obesity, insulin resistance, and type 2 diabetes mellitus, although the mechanisms are still poorly understood. Adipose tissue plays an important role in BCAA homeostasis by actively metabolizing circulating BCAA. In this work, we have investigated the link between BCAA catabolism and fatty acid synthesis in 3T3-L1 adipocytes using parallel 13C-labeling experiments, mass spectrometry and model-based isotopomer data analysis. Specifically, we performed parallel labeling experiments with four fully 13C-labeled tracers, [U-13C]valine, [U-13C]leucine, [U-13C]isoleucine and [U-13C]glutamine. We measured mass isotopomer distributions of fatty acids and intracellular metabolites by GC-MS and analyzed the data using the isotopomer spectral analysis (ISA framework. We demonstrate that 3T3-L1 adipocytes accumulate significant amounts of even chain length (C14:0, C16:0 and C18:0 and odd chain length (C15:0 and C17:0 fatty acids under standard cell culture conditions. Using a novel GC-MS method, we demonstrate that propionyl-CoA acts as the primer on fatty acid synthase for the production of odd chain fatty acids. BCAA contributed significantly to the production of all fatty acids. Leucine and isoleucine contributed at least 25% to lipogenic acetyl-CoA pool, and valine and isoleucine contributed 100% to lipogenic propionyl-CoA pool. Our results further suggest that low activity of methylmalonyl-CoA mutase and mass action kinetics of propionyl-CoA on fatty acid synthase result in high rates of odd chain fatty acid synthesis in 3T3-L1 cells. Overall, this work provides important new insights into the connection between BCAA catabolism and fatty acid synthesis in adipocytes and underscores the high capacity of adipocytes for metabolizing BCAA.

  17. Catabolism of Branched Chain Amino Acids Contributes Significantly to Synthesis of Odd-Chain and Even-Chain Fatty Acids in 3T3-L1 Adipocytes.

    Science.gov (United States)

    Crown, Scott B; Marze, Nicholas; Antoniewicz, Maciek R

    2015-01-01

    The branched chain amino acids (BCAA) valine, leucine and isoleucine have been implicated in a number of diseases including obesity, insulin resistance, and type 2 diabetes mellitus, although the mechanisms are still poorly understood. Adipose tissue plays an important role in BCAA homeostasis by actively metabolizing circulating BCAA. In this work, we have investigated the link between BCAA catabolism and fatty acid synthesis in 3T3-L1 adipocytes using parallel 13C-labeling experiments, mass spectrometry and model-based isotopomer data analysis. Specifically, we performed parallel labeling experiments with four fully 13C-labeled tracers, [U-13C]valine, [U-13C]leucine, [U-13C]isoleucine and [U-13C]glutamine. We measured mass isotopomer distributions of fatty acids and intracellular metabolites by GC-MS and analyzed the data using the isotopomer spectral analysis (ISA) framework. We demonstrate that 3T3-L1 adipocytes accumulate significant amounts of even chain length (C14:0, C16:0 and C18:0) and odd chain length (C15:0 and C17:0) fatty acids under standard cell culture conditions. Using a novel GC-MS method, we demonstrate that propionyl-CoA acts as the primer on fatty acid synthase for the production of odd chain fatty acids. BCAA contributed significantly to the production of all fatty acids. Leucine and isoleucine contributed at least 25% to lipogenic acetyl-CoA pool, and valine and isoleucine contributed 100% to lipogenic propionyl-CoA pool. Our results further suggest that low activity of methylmalonyl-CoA mutase and mass action kinetics of propionyl-CoA on fatty acid synthase result in high rates of odd chain fatty acid synthesis in 3T3-L1 cells. Overall, this work provides important new insights into the connection between BCAA catabolism and fatty acid synthesis in adipocytes and underscores the high capacity of adipocytes for metabolizing BCAA.

  18. Catabolism of Branched Chain Amino Acids Contributes Significantly to Synthesis of Odd-Chain and Even-Chain Fatty Acids in 3T3-L1 Adipocytes.

    Science.gov (United States)

    Crown, Scott B; Marze, Nicholas; Antoniewicz, Maciek R

    2015-01-01

    The branched chain amino acids (BCAA) valine, leucine and isoleucine have been implicated in a number of diseases including obesity, insulin resistance, and type 2 diabetes mellitus, although the mechanisms are still poorly understood. Adipose tissue plays an important role in BCAA homeostasis by actively metabolizing circulating BCAA. In this work, we have investigated the link between BCAA catabolism and fatty acid synthesis in 3T3-L1 adipocytes using parallel 13C-labeling experiments, mass spectrometry and model-based isotopomer data analysis. Specifically, we performed parallel labeling experiments with four fully 13C-labeled tracers, [U-13C]valine, [U-13C]leucine, [U-13C]isoleucine and [U-13C]glutamine. We measured mass isotopomer distributions of fatty acids and intracellular metabolites by GC-MS and analyzed the data using the isotopomer spectral analysis (ISA) framework. We demonstrate that 3T3-L1 adipocytes accumulate significant amounts of even chain length (C14:0, C16:0 and C18:0) and odd chain length (C15:0 and C17:0) fatty acids under standard cell culture conditions. Using a novel GC-MS method, we demonstrate that propionyl-CoA acts as the primer on fatty acid synthase for the production of odd chain fatty acids. BCAA contributed significantly to the production of all fatty acids. Leucine and isoleucine contributed at least 25% to lipogenic acetyl-CoA pool, and valine and isoleucine contributed 100% to lipogenic propionyl-CoA pool. Our results further suggest that low activity of methylmalonyl-CoA mutase and mass action kinetics of propionyl-CoA on fatty acid synthase result in high rates of odd chain fatty acid synthesis in 3T3-L1 cells. Overall, this work provides important new insights into the connection between BCAA catabolism and fatty acid synthesis in adipocytes and underscores the high capacity of adipocytes for metabolizing BCAA. PMID:26710334

  19. Attenuation of the protein wasting associated with bed rest by branched-chain amino acids

    Science.gov (United States)

    Stein, T. P.; Schluter, M. D.; Leskiw, M. J.; Boden, G.

    1999-01-01

    Bed rest is generally accepted as being an appropriate ground-based model for human spaceflight. The objectives of this study were to test the hypothesis that increasing the amount of branched-chain amino acids (BCAAs) in the diet could attenuate the protein loss associated with bed rest. Nineteen healthy subjects were randomized into two groups according to diet. During the 6 d of bed rest, the diets were supplemented with either 30 mmol/d each of three non-essential amino acids, glycine, serine, and alanine (control group), or with 30 mmol/d each of the BCAAs, leucine, isoleucine, and valine (BCAA group). Nutrition was supplied as a commercially available defined formula diet at a rate of 1.3 x REE. Nitrogen (N) balance and urinary 3-MeH excretion were determined for the 6 d. In our results, the urine-based estimate of N balance was 22.2 +/- 14.4 (n = 9) mg N.kg-1.d-1 and 60.5 +/- 10.1 mg (n = 8) N.kg-1.d-1 for the control and BCAA-supplemented groups, respectively (P < 0.05). Urinary 3-MeH excretion was unchanged in both groups with bed rest. We conclude that BCAA supplementation attenuates the N loss during short-term bed rest.

  20. Genetic analysis of pathway regulation for enhancing branched-chain amino acid biosynthesis in plants

    KAUST Repository

    Chen, Hao

    2010-08-01

    The branched-chain amino acids (BCAAs) valine, leucine and isoleucine are essential amino acids that play critical roles in animal growth and development. Animals cannot synthesize these amino acids and must obtain them from their diet. Plants are the ultimate source of these essential nutrients, and they synthesize BCAAs through a conserved pathway that is inhibited by its end products. This feedback inhibition has prevented scientists from engineering plants that accumulate high levels of BCAAs by simply over-expressing the respective biosynthetic genes. To identify components critical for this feedback regulation, we performed a genetic screen for Arabidopsis mutants that exhibit enhanced resistance to BCAAs. Multiple dominant allelic mutations in the VALINE-TOLERANT 1 (VAT1) gene were identified that conferred plant resistance to valine inhibition. Map-based cloning revealed that VAT1 encodes a regulatory subunit of acetohydroxy acid synthase (AHAS), the first committed enzyme in the BCAA biosynthesis pathway. The VAT1 gene is highly expressed in young, rapidly growing tissues. When reconstituted with the catalytic subunit in vitro, the vat1 mutant-containing AHAS holoenzyme exhibits increased resistance to valine. Importantly, transgenic plants expressing the mutated vat1 gene exhibit valine tolerance and accumulate higher levels of BCAAs. Our studies not only uncovered regulatory characteristics of plant AHAS, but also identified a method to enhance BCAA accumulation in crop plants that will significantly enhance the nutritional value of food and feed. © 2010 Blackwell Publishing Ltd.

  1. Defects in muscle branched-chain amino acid oxidation contribute to impaired lipid metabolism

    DEFF Research Database (Denmark)

    Lerin, Carles; Goldfine, Allison B; Boes, Tanner;

    2016-01-01

    OBJECTIVE: Plasma levels of branched-chain amino acids (BCAA) are consistently elevated in obesity and type 2 diabetes (T2D) and can also prospectively predict T2D. However, the role of BCAA in the pathogenesis of insulin resistance and T2D remains unclear. METHODS: To identify pathways related t...... catabolism may contribute to the development of insulin resistance by perturbing both amino acid and fatty acid metabolism and suggest that targeting BCAA metabolism may hold promise for prevention or treatment of T2D....... methylmalonyl-CoA mutase (Mut) and assessed the effects of altered BCAA flux on lipid and glucose homeostasis. RESULTS: Our data demonstrate perturbed BCAA metabolism and fatty acid oxidation in muscle from insulin resistant humans. Experimental alterations in BCAA flux in cultured cells similarly modulate...... fatty acid oxidation. Mut heterozygosity in mice alters muscle lipid metabolism in vivo, resulting in increased muscle triglyceride accumulation, increased plasma glucose, hyperinsulinemia, and increased body weight after high-fat feeding. CONCLUSIONS: Our data indicate that impaired muscle BCAA...

  2. CRYSTALLIZATION AND MECHANICAL PROPERTIES OF BLENDS OF METALLOCENE SHORT CHAIN BRANCHED POLYETHYLENE WITH CONVENTIONAL POLYOLEFINS

    Institute of Scientific and Technical Information of China (English)

    Ya Peng; Qiang Fu

    2004-01-01

    Metallocene-catalyzed short chain branched polyethylene (SCBPE) was blended with LDPE, HDPE, PS, EPDM and iPP in the weight proportions of 80 and 20. The crystallization and mechanical properties of these blends were studied by PLM, DSC and DMA. It has been observed in PLM that SCBPE/LDPE, SCBPE/HDPE and SCBPE/EPDM can form band spherulites whose band width and size are both smaller than that of the pure SCBPE. Tiny crystallites are observed in the completely immiscible SCBPE/PS blend. The crystallites in SCBPE/iPP are very small and only irregular spherulites are seen. The crystallization kinetics and mechanical properties of SCBPE are greatly affected by the second polyolefin, but in a different way, depending on the phase behavior and the modulus of the second components. SCBPE may be phase miscible in the melt with HDPE, LDPE and EPDM and co-crystallize together with HDPE or LDPE during cooling. A big change of crystal morphology and crystallization kinetics is seen in SCBPE/iPP blend compared with pure SCBPE and the lowest tanδ is also seen for this system. DMA results show that the tensile modulus of the blends has nothing to do with phase behavior,but only depends on the modulus of the second component.

  3. Associations between plasma branched-chain amino acids, β-aminoisobutyric acid and body composition.

    Science.gov (United States)

    Rietman, Annemarie; Stanley, Takara L; Clish, Clary; Mootha, Vamsi; Mensink, Marco; Grinspoon, Steven K; Makimura, Hideo

    2016-01-01

    Plasma branched-chain amino acids (BCAA) are elevated in obesity and associated with increased cardiometabolic risk. β-Aminoisobutyric acid (B-AIBA), a recently identified small molecule metabolite, is associated with decreased cardiometabolic risk. Therefore, we investigated the association of BCAA and B-AIBA with each other and with detailed body composition parameters, including abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). A cross-sectional study was carried out with lean (n 15) and obese (n 33) men and women. Detailed metabolic evaluations, including measures of body composition, insulin sensitivity and plasma metabolomics were completed. Plasma BCAA were higher (1·6 (se 0·08) (×10(7)) v. 1·3 (se 0·06) (×10(7)) arbitrary units; P = 0·005) in obese v. lean subjects. BCAA were positively associated with VAT (R 0·49; P = 0·0006) and trended to an association with SAT (R 0·29; P = 0·052). The association between BCAA and VAT, but not SAT, remained significant after controlling for age, sex and race on multivariate modelling (P insulin sensitivity (Matsuda index: R -0·50, P = 0·0004; glucose AUC: R 0·53, P  0·05). Plasma B-AIBA was associated with parameters of insulin sensitivity (Matsuda index R 0·36, P = 0·01; glucose AUC: R -0·30, P = 0·04). Plasma BCAA levels were positively correlated with VAT and markers of insulin resistance. The results suggest a possible complex role of adipose tissue in BCAA homeostasis and insulin resistance. PMID:27313851

  4. Plasma branched-chain amino acids and incident cardiovascular disease in the PREDIMED trial

    Science.gov (United States)

    Ruiz-Canela, Miguel; Toledo, Estefania; Clish, Clary B.; Hruby, Adela; Liang, Liming; Salas-Salvadó, Jordi; Razquin, Cristina; Corella, Dolores; Estruch, Ramón; Ros, Emilio; Fitó, Montserrat; Gómez-Gracia, Enrique; Arós, Fernando; Fiol, Miquel; Lapetra, José; Serra-Majem, Lluis; Martínez-González, Miguel A.; Hu, Frank B.

    2016-01-01

    Background The role of branched-chain amino acids (BCAAs) in cardiovascular disease (CVD) remains poorly understood. We hypothesized that baseline BCAA concentrations predict future risk of CVD and that a Mediterranean Diet (MedDiet) intervention may counteract this effect. Methods We developed a case-cohort study within the “PREvención con DIeta MEDiterránea” (PREDIMED), with 226 incident CVD cases and 781 non-cases. We used LC-MS/MS to measure plasma BCAAs (leucine, isoleucine and valine), both at baseline and after 1-year follow-up. The primary outcome was a composite of incident stroke, myocardial infarction, or cardiovascular death. Results After adjustment for potential confounders, baseline leucine and isoleucine concentrations were associated with higher CVD risk: the hazard ratios (HRs) for the highest vs. lowest quartile were 1.70 (95% confidence interval, 1.05–2.76) and 2.09 (1.27–3.44), respectively. Stronger associations were found for stroke. For both CVD and stroke, we found higher HRs across successive quartiles of BCAAs in the control group than in the MedDiet groups. Using stroke as the outcome, a significant interaction (P=0.009) between the baseline BCAA score and the intervention with MedDiet was observed. No significant effect of the intervention on 1-yr changes in BCAAs nor any association between 1-year changes in BCAAs and CVD were observed. Conclusions Higher concentrations of baseline BCAAs were associated with increased risk of CVD, especially stroke, in a high cardiovascular risk population. A Mediterranean-style diet had a negligible effect on 1-year changes in BCAAs, but it may counteract the harmful effects of BCAAs on stroke. PMID:26888892

  5. Comparative Genomics of Regulation of Fatty Acid and Branched-chain Amino Acid Utilization in Proteobacteria

    Energy Technology Data Exchange (ETDEWEB)

    Kazakov, Alexey E.; Rodionov, Dmitry A.; Arkin, Adam Paul; Dubchak, Inna; Gelfand, Mikhail S.; Alm, Eric

    2008-10-31

    Bacteria can use branched-chain amino acids (ILV, i.e. isoleucine, leucine, valine) and fatty acids (FA) as sole carbon and energy sources convering ILV into acetyl-CoA, propanoyl-CoA and propionyl-CoA, respectively. In this work, we used the comparative genomic approach to identify candidate transcriptional factors and DNA motifs that control ILV and FA utilization pathways in proteobacteria. The metabolic regulons were characterized based on the identification and comparison of candidate transcription factor binding sites in groups of phylogenetically related genomes. The reconstructed ILV/FA regulatory network demonstrates considerable variability and involves six transcriptional factors from the MerR, TetR and GntR families binding to eleven distinct DNA motifs. The ILV degradation genes in gamma- and beta-proteobacteria are mainly regulated by anovel regulator from the MerR family (e.g., LiuR in Pseudomonas aeruginosa) (40 species), in addition, the TetR-type regulator LiuQ was identified in some beta-proteobacteria (8 species). Besides the core set of ILV utilization genes, the LiuR regulon in some lineages is expanded to include genes from other metabolic pathways, such as the glyoxylate shunt and glutamate synthase in the Shewanella species. The FA degradation genes are controlled by four regulators including FadR in gamma-proteobacteria (34 species), PsrA in gamma- and beta-proteobacteria (45 species), FadP in beta-proteobacteria (14 species), and LiuR orthologs in alpha-proteobacteria (22 species). The remarkable variability of the regulatory systems associated with the FA degradation pathway is discussed from the functional and evolutionary points of view.

  6. Branched-chain amino acid supplementation during bed rest: effect on recovery

    Science.gov (United States)

    Stein, T. P.; Donaldson, M. R.; Leskiw, M. J.; Schluter, M. D.; Baggett, D. W.; Boden, G.

    2003-01-01

    Bed rest is associated with a loss of protein from the weight-bearing muscle. The objectives of this study are to determine whether increasing dietary branched-chain amino acids (BCAAs) during bed rest improves the anabolic response after bed rest. The study consisted of a 1-day ambulatory period, 14 days of bed rest, and a 4-day recovery period. During bed rest, dietary intake was supplemented with either 30 mmol/day each of glycine, serine, and alanine (group 1) or with 30 mmol/day each of the three BCAAs (group 2). Whole body protein synthesis was determined with U-(15)N-labeled amino acids, muscle, and selected plasma protein synthesis with l-[(2)H(5)]phenylalanine. Total glucose production and gluconeogenesis from alanine were determined with l-[U-(13)C(3)]alanine and [6,6-(2)H(2)]glucose. During bed rest, nitrogen (N) retention was greater with BCAA feeding (56 +/- 6 vs. 26 +/- 12 mg N. kg(-1). day(-1), P supplementation on either whole body, muscle, or plasma protein synthesis or the rate of 3-MeH excretion. Muscle tissue free amino acid concentrations were increased during bed rest with BCAA (0.214 +/- 0.066 vs. 0.088 +/- 0.12 nmol/mg protein, P glucose production and gluconeogenesis from alanine were unchanged with bed rest but were significantly reduced (P < 0.05) with the BCAA group in the recovery phase. In conclusion, the improved N retention during bed rest is due, at least in part, to accretion of amino acids in the tissue free amino acid pools. The amount accreted is not enough to impact protein kinetics in the recovery phase but does improve N retention by providing additional essential amino acids in the early recovery phase.

  7. Regulation of indole-3-acetic acid biosynthesis by branched-chain amino acids in Enterobacter cloacae UW5.

    Science.gov (United States)

    Parsons, Cassandra V; Harris, Danielle M M; Patten, Cheryl L

    2015-09-01

    The soil bacterium Enterobacter cloacae UW5 produces the rhizosphere signaling molecule indole-3-acetic acid (IAA) via the indolepyruvate pathway. Expression of indolepyruvate decarboxylase, a key pathway enzyme encoded by ipdC, is upregulated by the transcription factor TyrR in response to aromatic amino acids. Some members of the TyrR regulon may also be controlled by branched-chain amino acids and here we show that expression from the ipdC promoter and production of IAA are downregulated by valine, leucine and isoleucine. Regulation of the IAA synthesis pathway by both aromatic and branched-chain amino acids suggests a broader role for this pathway in bacterial physiology, beyond plant interactions.

  8. Purification, crystallization and preliminary X-ray crystallographic analysis of branched-chain aminotransferase from Deinococcus radiodurans

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chung-Der; Huang, Tien-Feng [Department of Physics, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Lin, Chih-Hao [Institute of Biological Chemistry, National Taiwan University, Taipei 110,Taiwan (China); Guan, Hong-Hsiang; Hsieh, Yin-Cheng [Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China); Institute of Bioinformatics and Structural Biology, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Lin, Yi-Hung; Huang, Yen-Chieh; Liu, Ming-Yih [Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China); Chang, Wen-Chang, E-mail: wchang@ntu.edu.tw [Institute of Biological Chemistry, National Taiwan University, Taipei 110,Taiwan (China); Chen, Chun-Jung, E-mail: wchang@ntu.edu.tw [Department of Physics, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China)

    2007-06-01

    The crystallization of branched-chain aminotransferase from D. radiodurans is described. The branched-chain amino-acid aminotransferase (BCAT), which requires pyridoxal 5′-phosphate (PLP) as a cofactor, is a key enzyme in the biosynthetic pathway of the hydrophobic amino acids leucine, isoleucine and valine. DrBCAT from Deinococcus radiodurans, which has a molecular weight of 40.9 kDa, was crystallized using the hanging-drop vapour-diffusion method. According to X-ray diffraction data to 2.50 Å resolution from a DrBCAT crystal, the crystal belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 56.37, b = 90.70, c = 155.47 Å. Preliminary analysis indicates the presence of two DrBCAT molecules in the asymmetric unit, with a solvent content of 47.52%.

  9. Effect of lipid supplementation on milk odd- and branched-chain fatty acids in dairy cows.

    Science.gov (United States)

    Baumann, E; Chouinard, P Y; Lebeuf, Y; Rico, D E; Gervais, R

    2016-08-01

    Eight ruminally fistulated, multiparous Holstein cows were arranged in a double 4×4 Latin square with 14-d periods to investigate the effects of lipid supplementation on performance, rumen parameters, the milk odd- and branched-chain fatty acid (OBCFA) profile, and the relationships between milk OBCFA and rumen parameters. Lipid supplementation is known to inhibit microbial growth in the rumen, decrease de novo microbial fatty acid synthesis, and increase the uptake of circulating fatty acids by the mammary gland; treatments were selected to isolate these effects on the milk OBCFA profile. The 4 treatments were (1) a lipid-free emulsion medium infused in the rumen (CTL), (2) soybean oil as a source of polyunsaturated fatty acids infused in the rumen (RSO), (3) saturated fatty acids (38% 16:0, 40% 18:0) infused in the rumen (RSF), and (4) saturated fatty acids infused in the abomasum (ASF). Fat supplements were provided continuously as emulsions at a rate of 450g/d. Preplanned contrasts compared CTL to RSO, RSO to RSF, and RSF to ASF. Infusing RSO slightly decreased ruminal pH, but did not affect volatile fatty acids profile and milk fat concentration as compared with CTL. The yields of energy-corrected milk, fat, and protein were greater with RSF compared with RSO. The concentration of odd-chain fatty acids was decreased by RSO, whereas even-chain iso fatty acids were not affected. Milk fat concentration of 17:0 + cis-9 17:1 was higher for RSF than for RSO, due to the saturated fatty acids supplement containing 2% 17:0 + cis-9 17:1. Limited differences were observed in the milk OBCFA profile between RSF and ASF. A multiple regression analysis yielded the following equation for predicting rumen pH based on milk fatty acids: pH=6.24 - (0.56×4:0) + (1.67 × iso 14:0) + (4.22 × iso 15:0) + (9.41×22:0). Rumen propionate concentration was negatively correlated with milk fat concentration of iso 14:0 and positively correlated with milk 15:0, whereas the acetate

  10. Bolus ingestion of individual branched-chain amino acids alters plasma amino acid profiles in young healthy men

    OpenAIRE

    Matsumoto, Takuya; Nakamura, Koichi; Matsumoto, Hideki; Sakai, Ryosei; Kuwahara, Tomomi; Kadota, Yoshihiro; Kitaura, Yasuyuki; SATO, JUICHI; Shimomura, Yoshiharu

    2014-01-01

    Physiological conditions in humans affect plasma amino acid profiles that might have potential for medical use. Because the branched-chain amino acids (BCAAs) leucine, isoleucine and valine are used as medicines and supplements, we investigated the acute effects of individual BCAAs (10–90 mg/kg body weight) or mixed BCAAs ingested as a bolus on plasma amino acid profiles in young healthy men. Plasma leucine levels rapidly increased and peaked around 30 min after leucine ingestion. Concentrati...

  11. Branched-chain amino acids attenuate early kidney injury in diabetic rats.

    Science.gov (United States)

    Mi, Na; Zhang, Xiu Juan; Ding, Yan; Li, Guo Hua; Wang, Wei Dong; Xian, Hui Xia; Xu, Jin

    2015-10-16

    Diabetic nephropathy (DN) is the most severe diabetic microvascular complication. The pathogenesis of diabetic nephropathy is complex, and oxidative stress plays an important role in the development of diabetic nephropathy. Elevated reactive oxygen species (ROS) levels activate various signaling pathways and influence the activities of transforming growth factor-β (TGF-β) and matrix metalloproteinase-9 (MMP-9), which contributes to glomerular hypertrophy. Branched-chain amino acids (BCAAs) are widely used in clinical treatment, and BCAAs can reduce the oxidative stress associated with the diabetic pancreas and some liver diseases. Thus, the aim of the present study was to determine whether BCAAs could attenuate oxidative stress in the kidneys of streptozotocin (STZ)-induced diabetic rats to prevent early diabetic kidney injury. Male Wistar rats were fed for two weeks with a normal chow diet or a high-fat diet in which 40% of calories were derived from fat. After this two-week period, the mice fed normal chow were injected with vehicle, while the high-fat diet group was injected intraperitoneally (i.p.) with 40 mg/kg STZ. The STZ-treated group was randomly divided into four subgroups that were treated with different doses of BCAAs or vehicle for two months by oral gavage. Plasma glucose, plasma creatinine, urinary protein and JNK, TGF-β, and MMP-9 mRNA and protein expression levels were measured in the rats. The ROS levels and proteinuria in the STZ-induced diabetic rats were significantly higher than those in the control groups. Moreover, early kidney injury occurred in the STZ-induced diabetic rats. However, BCAAs treatment decreased ROS levels, proteinuria and kidney injury. Moreover, JNK, TGF-β and MMP-9 mRNA and protein levels were significantly increased in the diabetic rats when compared with the control rats, and BCAAs treatment reversed these changes. Our results suggest that BCAAs counter oxidative stress in the kidneys of diabetic rats and alleviate

  12. Branching Processes and Evolution at the Ends of a Food Chain

    OpenAIRE

    Caldarelli, G.; Tebaldi, C.; A. L. Stella(GNSM, Univ. and INFN, Padova)

    1996-01-01

    In a critically self--organized model of punctuated equilibrium, boundaries determine peculiar scaling of the size distribution of evolutionary avalanches. This is derived by an inhomogeneous generalization of standard branching processes, extending previous mean field descriptions and yielding $\

  13. Origin of Broad Visible Emission from Branched Polysilane and Polygermane Chains

    Science.gov (United States)

    Watanabe, Akira; Sato, Takaaki; Matsuda, Minoru

    2001-11-01

    The emission properties of branched polysilane and polygermane are studied using time-resolved emission spectroscopy. As branched polymers, the organosilicon cluster (OSI) and organogermanium cluster (OGE) are investigated, which are prepared from tetrachlorosilane and tetrachlorogermane, respectively, and have a hyperbranched structure. The broad visible emissions of OSI and OGE are explained by the energy diagram based on a configuration coordinate model, and the excited states are attributed to a localized state around the branching point. The molecular orbital (MO) calculation suggested the formation of a localized state by the distortion around the branching point in the excited state. The potential barrier for the nonradiative relaxation process was determined from the temperature dependence of the emission lifetime.

  14. Enhanced production of branched-chain fatty acids by replacing β-ketoacyl-(acyl-carrier-protein) synthase III (FabH).

    Science.gov (United States)

    Jiang, Wen; Jiang, Yanfang; Bentley, Gayle J; Liu, Di; Xiao, Yi; Zhang, Fuzhong

    2015-08-01

    Branched-chain fatty acids (BCFAs) are important precursors for the production of advanced biofuels with improved cold-flow properties. Previous efforts in engineering type II fatty acid synthase (FAS) for BCFA production suffered from low titers and/or the co-production of a large amount of straight-chain fatty acids (SCFAs), making it nearly impossible for further conversion of BCFAs to branched biofuels. Synthesis of both SCFAs and BCFAs requires FabH, the only β-ketoacyl-(acyl-carrier-protein) synthase in Escherichia coli that catalyzes the initial condensation reaction between malonyl-ACP and a short-chain acyl-CoA. In this study, we demonstrated that replacement of the acetyl-CoA-specific E. coli FabH with a branched-chain-acyl-CoA-specific FabH directed the flux to the synthesis of BCFAs, resulting in a significant enhancement in BCFA titer compared to a strain containing both acetyl-CoA- and branched-chain-acyl-CoA-specific FabHs. We further demonstrated that the composition of BCFAs can be tuned by engineering the upstream pathway to control the supply of different branched-chain acyl-CoAs, leading to the production either even-chain-iso-, odd-chain-iso-, or odd-chain-anteiso-BCFAs separately. Overall, the top-performing strain from this study produced BCFAs at 126 mg/L, comprising 52% of the total free fatty acids. PMID:25788017

  15. Genes Involved in Formation and Attachment of a Two-Carbon Chain as a Component of Eurekanate, a Branched-Chain Sugar Moiety of Avilamycin A

    OpenAIRE

    Treede, Irina; Hauser, Gerd; Mühlenweg, Agnes; Hofmann, Carsten; Schmidt, Maraike; Weitnauer, Gabriele; Glaser, Steffen; Bechthold, Andreas

    2005-01-01

    Eurekanate belongs to the important class of branched-chain carbohydrates present in a wide variety of natural sources. It is a component of avilamycin A, a potent inhibitor of bacterial protein synthesis targeting the 50S ribosomal subunit. The present work provides experimental proof for the function of two genes of the avilamycin biosynthetic gene cluster, aviB1 and aviO2, that are both involved in avilamycin structure modification. The functions of both genes were identified by gene inact...

  16. Short branched-chain C6 carboxylic acids result in increased growth, novel 'unnatural' fatty acids and increased membrane fluidity in a Listeria monocytogenes branched-chain fatty acid-deficient mutant.

    Science.gov (United States)

    Sen, Suranjana; Sirobhushanam, Sirisha; Hantak, Michael P; Lawrence, Peter; Brenna, J Thomas; Gatto, Craig; Wilkinson, Brian J

    2015-10-01

    Listeria monocytogenes is a psychrotolerant food borne pathogen, responsible for the high fatality disease listeriosis, and expensive food product recalls. Branched-chain fatty acids (BCFAs) of the membrane play a critical role in providing appropriate membrane fluidity and optimum membrane biophysics. The fatty acid composition of a BCFA-deficient mutant is characterized by high amounts of straight-chain fatty acids and even-numbered iso fatty acids, in contrast to the parent strain where odd-numbered anteiso fatty acids predominate. The presence of 2-methylbutyrate (C5) stimulated growth of the mutant at 37°C and restored growth at 10°C along with the content of odd-numbered anteiso fatty acids. The C6 branched-chain carboxylic acids 2-ethylbutyrate and 2-methylpentanoate also stimulated growth to a similar extent as 2-methylbutyrate. However, 3-methylpentanoate was ineffective in rescuing growth. 2-Ethylbutyrate and 2-methylpentanoate led to novel major fatty acids in the lipid profile of the membrane that were identified as 12-ethyltetradecanoic acid and 12-methylpentadecanoic acid respectively. Membrane anisotropy studies indicated that growth of strain MOR401 in the presence of these precursors increased its membrane fluidity to levels of the wild type. Cells supplemented with 2-methylpentanoate or 2-ethylbutyrate at 10°C shortened the chain length of novel fatty acids, thus showing homeoviscous adaptation. These experiments use the mutant as a tool to modulate the membrane fatty acid compositions through synthetic precursor supplementation, and show how existing enzymes in L. monocytogenes adapt to exhibit non-native activity yielding unique 'unnatural' fatty acid molecules, which nevertheless possess the correct biophysical properties for proper membrane function in the BCFA-deficient mutant. PMID:26225744

  17. Volatile profiling reveals intracellular metabolic changes in Aspergillus parasiticus: veA regulates branched chain amino acid and ethanol metabolism

    Directory of Open Access Journals (Sweden)

    Roze Ludmila V

    2010-08-01

    Full Text Available Abstract Background Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine; we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions 1 Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2 VeA coordinates the

  18. Volatile profiling reveals intracellular metabolic changes in Aspergillus parasiticus: veA regulates branched chain amino acid and ethanol metabolism

    Science.gov (United States)

    2010-01-01

    Background Filamentous fungi in the genus Aspergillus produce a variety of natural products, including aflatoxin, the most potent naturally occurring carcinogen known. Aflatoxin biosynthesis, one of the most highly characterized secondary metabolic pathways, offers a model system to study secondary metabolism in eukaryotes. To control or customize biosynthesis of natural products we must understand how secondary metabolism integrates into the overall cellular metabolic network. By applying a metabolomics approach we analyzed volatile compounds synthesized by Aspergillus parasiticus in an attempt to define the association of secondary metabolism with other metabolic and cellular processes. Results Volatile compounds were examined using solid phase microextraction - gas chromatography/mass spectrometry. In the wild type strain Aspergillus parasiticus SU-1, the largest group of volatiles included compounds derived from catabolism of branched chain amino acids (leucine, isoleucine, and valine); we also identified alcohols, esters, aldehydes, and lipid-derived volatiles. The number and quantity of the volatiles produced depended on media composition, time of incubation, and light-dark status. A block in aflatoxin biosynthesis or disruption of the global regulator veA affected the volatile profile. In addition to its multiple functions in secondary metabolism and development, VeA negatively regulated catabolism of branched chain amino acids and synthesis of ethanol at the transcriptional level thus playing a role in controlling carbon flow within the cell. Finally, we demonstrated that volatiles generated by a veA disruption mutant are part of the complex regulatory machinery that mediates the effects of VeA on asexual conidiation and sclerotia formation. Conclusions 1) Volatile profiling provides a rapid, effective, and powerful approach to identify changes in intracellular metabolic networks in filamentous fungi. 2) VeA coordinates the biosynthesis of secondary

  19. Scientific Opinion on the safety and efficacy of branched-chain primary aliphatic alcohols/aldehydes/acids, acetals and esters with esters containing branched-chain alcohols and acetals containing branched-chain aldehydes (chemical group 2 when used as flavourings for all animal species

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP

    2012-10-01

    Full Text Available

    Chemical group 2 consists of branched-chain primary aliphatic alcohols/aldehydes/acids, acetals and esters with esters containing branched-chain alcohols and acetals containing branched-chain aldehydes, of which 34 are currently authorised for use as flavours in food. The use of 2-methylpropionic acid, isopentyl acetate, 3-methylbutyl butyrate and 2-methylbutyl acetate is safe at the proposed use level of 25 mg/kg complete feed for cattle, salmonids and non food producing animals and at 5 mg/kg complete feed for pigs and poultry. 2-Methylpropan-1-ol, isopentanol, 2-ethylhexan-1-ol, 2-methylpropanal, 3-methylbutanal, 2-methylbutyraldehyde, 3-methylbutyric acid, 2-methylvaleric acid, 2-ethylbutyric acid, 2-methylbutyric acid, 2-methylheptanoic acid, 4-methyloctanoic acid, isobutyl acetate, isobutyl butyrate, 3-methylbutyl propionate, 3-methylbutyl formate, glyceryl tributyrate, isobutyl isobutyrate, isopentyl isobutyrate, isobutyl isovalerate, isopentyl 2-methylbutyrate, 2-methylbutyl isovalerate and 2-methylbutyl butyrate are safe at the proposed use level of 5 mg/kg complete feed for all animal species. 3,7-Dimethyloctan-1-ol, 2-methylundecanal, 4-methylnonanoic acid, 3-methylbutyl hexanoate, 3-methylbutyl dodecanoate, 3-methylbutyl octanoate and 3-methylbutyl 3-methylbutyrate are safe at a maximum of 1.5 mg/kg complete feed for cattle, salmonids and non food-producing animals and of 1.0 mg/kg complete feed for pigs and poultry. No safety concern was identified for the consumer from the use of these compounds up to the highest safe level in feedingstuffs for all animal species. All compounds should be considered as irritants to skin, eyes and respiratory tract, and as skin sensitisers. The compounds do not pose a risk to the environment when used at concentrations considered safe for the target species. Since all compounds are used in food as flavourings, no further demonstration of efficacy is necessary.

  20. Neutral Pectin side chains of Amaranth (Amaranthus hypochondriacus) contain long, partially branched Arabinans and short galactans, both with terminal arabinopyranoses.

    Science.gov (United States)

    Wefers, Daniel; Tyl, Catrin E; Bunzel, Mirko

    2015-01-21

    Amaranth is a pseudocereal of high nutritional value, including a high dietary fiber content. Amaranth dietary fiber was suggested to contain large amounts of neutral rhamnogalacturonan I side chains. In this study, endo-arabinanase and endo-galactanase were used to liberate arabinan and galactan oligosaccharides from amaranth fiber. The liberated oligosaccharides were identified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and HPLC-MS(n) using standard compounds, which were isolated from amaranth, sugar beet, potato, and red clover sprouts and characterized by one- and two-dimensional NMR spectroscopy. It was demonstrated that insoluble amaranth arabinans have linear and branched areas, with the O-3 position being the dominant branching point. Minor amounts of branches at position O-2 and double substitution were also found. Amaranth arabinans were also demonstrated to contain terminal α-(1→5)-linked l-arabinopyranose units. In addition, it was evidenced that galactans from amaranth seeds are composed of β-(1→4)-linked d-galactopyranose units, which can also be terminated with l-arabinopyranose units. In direct comparison to structural elucidation of amaranth fiber by using methylation analysis, the advantage of the enzymatic approach over methylation analysis was demonstrated. PMID:25529336

  1. Neutral Pectin side chains of Amaranth (Amaranthus hypochondriacus) contain long, partially branched Arabinans and short galactans, both with terminal arabinopyranoses.

    Science.gov (United States)

    Wefers, Daniel; Tyl, Catrin E; Bunzel, Mirko

    2015-01-21

    Amaranth is a pseudocereal of high nutritional value, including a high dietary fiber content. Amaranth dietary fiber was suggested to contain large amounts of neutral rhamnogalacturonan I side chains. In this study, endo-arabinanase and endo-galactanase were used to liberate arabinan and galactan oligosaccharides from amaranth fiber. The liberated oligosaccharides were identified by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and HPLC-MS(n) using standard compounds, which were isolated from amaranth, sugar beet, potato, and red clover sprouts and characterized by one- and two-dimensional NMR spectroscopy. It was demonstrated that insoluble amaranth arabinans have linear and branched areas, with the O-3 position being the dominant branching point. Minor amounts of branches at position O-2 and double substitution were also found. Amaranth arabinans were also demonstrated to contain terminal α-(1→5)-linked l-arabinopyranose units. In addition, it was evidenced that galactans from amaranth seeds are composed of β-(1→4)-linked d-galactopyranose units, which can also be terminated with l-arabinopyranose units. In direct comparison to structural elucidation of amaranth fiber by using methylation analysis, the advantage of the enzymatic approach over methylation analysis was demonstrated.

  2. Sulfate-ion-assisted galvanic replacement tuning of silver dendrites to highly branched chains for effective SERS.

    Science.gov (United States)

    Zhang, Yunxia; Sun, Shaodong; Zhang, Xiaozhe; Tang, Linli; Song, Xiaoping; Yang, Zhimao

    2014-09-21

    Morphology is a primary part of designing metal nanocrystals and nanomaterials with controlled functional properties. Here, we demonstrate the potential of foreign sulfate ions to tune the silver dendrites to highly branched chains through a simple galvanic replacement reaction without introducing any organic surfactants. We further illustrate the underlying mechanism according to diffusion-limited aggregation (DLA) in the presence of sulfate ions. The special aspects of this simple synthetic strategy are the control of both the nucleation process and the subsequent crystal growth stage by using sulfate ions as the ionic surfactants thereby tuning the total surface energies on various crystal facets in solution and transforming crystal growth habits of the products. Moreover, the highly branched silver chains (HBSCs) with pure surfaces have been successfully employed as a Raman probe for surface-enhanced Raman spectroscopic analysis of rhodamine 6G (R6G). The particular morphology of those HBSCs also makes them find potential applications in biosensing, catalysis and optics. PMID:25084025

  3. The antifungal eugenol perturbs dual aromatic and branched-chain amino acid permeases in the cytoplasmic membrane of yeast.

    Directory of Open Access Journals (Sweden)

    Emad Darvishi

    Full Text Available Eugenol is an aromatic component of clove oil that has therapeutic potential as an antifungal drug, although its mode of action and precise cellular target(s remain ambiguous. To address this knowledge gap, a chemical-genetic profile analysis of eugenol was done using ∼4700 haploid Saccharomyces cerevisiae gene deletion mutants to reveal 21 deletion mutants with the greatest degree of susceptibility. Cellular roles of deleted genes in the most susceptible mutants indicate that the main targets for eugenol include pathways involved in biosynthesis and transport of aromatic and branched-chain amino acids. Follow-up analyses showed inhibitory effects of eugenol on amino acid permeases in the yeast cytoplasmic membrane. Furthermore, phenotypic suppression analysis revealed that eugenol interferes with two permeases, Tat1p and Gap1p, which are both involved in dual transport of aromatic and branched-chain amino acids through the yeast cytoplasmic membrane. Perturbation of cytoplasmic permeases represents a novel antifungal target and may explain previous observations that exposure to eugenol results in leakage of cell contents. Eugenol exposure may also contribute to amino acid starvation and thus holds promise as an anticancer therapeutic drug. Finally, this study provides further evidence of the usefulness of the yeast Gene Deletion Array approach in uncovering the mode of action of natural health products.

  4. Weight gain in anorexia nervosa does not ameliorate the faecal microbiota, branched chain fatty acid profiles, and gastrointestinal complaints

    Science.gov (United States)

    Mack, Isabelle; Cuntz, Ulrich; Grämer, Claudia; Niedermaier, Sabrina; Pohl, Charlotte; Schwiertz, Andreas; Zimmermann, Kurt; Zipfel, Stephan; Enck, Paul; Penders, John

    2016-01-01

    The gut microbiota not only influences host metabolism but can also affect brain function and behaviour through the microbiota-gut-brain axis. To explore the potential role of the intestinal microbiota in anorexia nervosa (AN), we comprehensively investigated the faecal microbiota and short-chain fatty acids in these patients before (n = 55) and after weight gain (n = 44) in comparison to normal-weight participants (NW, n = 55) along with dietary intake and gastrointestinal complaints. We show profound microbial perturbations in AN patients as compared to NW participants, with higher levels of mucin-degraders and members of Clostridium clusters I, XI and XVIII and reduced levels of the butyrate-producing Roseburia spp. Branched-chain fatty acid concentrations, being markers for protein fermentation, were elevated. Distinct perturbations in microbial community compositions were observed for individual restrictive and binge/purging AN-subtypes. Upon weight gain, microbial richness increased, however perturbations in intestinal microbiota and short chain fatty acid profiles in addition to several gastrointestinal symptoms did not recover. These insights provide new leads to modulate the intestinal microbiota in order to improve the outcomes of the standard therapy. PMID:27229737

  5. Characterization of a novel debranching enzyme from Nostoc punctiforme possessing a high specificity for long branched chains

    International Nuclear Information System (INIS)

    A novel debranching enzyme from Nostoc punctiforme PCC73102 (NPDE) exhibits hydrolysis activity toward both α-(1,6)- and α-(1,4)-glucosidic linkages. The action patterns of NPDE revealed that branched chains are released first, and the resulting maltooligosaccharides are then hydrolyzed. Analysis of the reaction with maltooligosaccharide substrates labeled with 14C-glucose at the reducing end shows that NPDE specifically liberates glucose from the reducing end. Kinetic analyses showed that the hydrolytic activity of NPDE is greatly affected by the length of the substrate. The catalytic efficiency of NPDE increased considerably upon using substrates that can occupy at least eight glycone subsites such as maltononaose and maltooctaosyl-α-(1,6)-β-cyclodextrin. These results imply that NPDE has a unique subsite structure consisting of -8 to +1 subsites. Given its unique subsite structure, side chains shorter than maltooctaose in amylopectin were resistant to hydrolysis by NPDE, and the population of longer side chains was reduced.

  6. Does Branched-Chain Amino Acids Supplementation Modulate Skeletal Muscle Remodeling through Inflammation Modulation? Possible Mechanisms of Action

    Directory of Open Access Journals (Sweden)

    Humberto Nicastro

    2012-01-01

    Full Text Available Skeletal muscle protein turnover is modulated by intracellular signaling pathways involved in protein synthesis, degradation, and inflammation. The proinflammatory status of muscle cells, observed in pathological conditions such as cancer, aging, and sepsis, can directly modulate protein translation initiation and muscle proteolysis, contributing to negative protein turnover. In this context, branched-chain amino acids (BCAAs, especially leucine, have been described as a strong nutritional stimulus able to enhance protein translation initiation and attenuate proteolysis. Furthermore, under inflammatory conditions, BCAA can be transaminated to glutamate in order to increase glutamine synthesis, which is a substrate highly consumed by inflammatory cells such as macrophages. The present paper describes the role of inflammation on muscle remodeling and the possible metabolic and cellular effects of BCAA supplementation in the modulation of inflammatory status of skeletal muscle and the consequences on protein synthesis and degradation.

  7. Effect of branched-chain fatty acids, 3-methylindole and 4-methylphenol on consumer sensory scores of grilled lamb meat.

    Science.gov (United States)

    Watkins, P J; Kearney, G; Rose, G; Allen, D; Ball, A J; Pethick, D W; Warner, R D

    2014-02-01

    Tenderness, flavour, overall liking and odour are important components of sheepmeat eating quality. Consumer assessment of these attributes has been made for carcasses from the Information Nucleus Flock (INF) of the Cooperative Research Centre for Sheep Industry Innovation. The concentrations of three branched chain fatty acids, 4-methyloctanoic (MOA), 4-ethyloctanoic (EOA) and 4-methylnonanoic acids (compounds related to 'mutton flavour' in cooked sheepmeat) and 3-methylindole and 4-methylphenol (compounds related to 'pastoral' flavour) were determined for 178 fat samples taken from INF carcasses. Statistical modelling revealed that both MOA and EOA impacted on the 'Like Smell' consumer sensory score of the cooked meat product (Pflavour. Obviously, reducing the effect of MOA and EOA on the odour of grilled lamb will improve consumer acceptance of the cooked product but other factors affecting the eating quality also need to be considered. PMID:22950976

  8. Ingestion of branched-chain amino acids and tryptophan during sustained exercise in man: failure to affect performance

    DEFF Research Database (Denmark)

    Van Hall, Gerrit; Raaymakers, J S; Saris, W H;

    1995-01-01

    1. An increased uptake of tryptophan in the brain may increase serotoninergic activity and recently has been suggested to be a cause of fatigue during prolonged exercise. The present study, therefore, investigates whether ingestion of tryptophan or the competing branched-chain amino acids (BCAAs......) affect performance. Ten endurance-trained male athletes were studied during cycle exercise at 70-75% maximal power output, while ingesting, ad random and double-blind, drinks that contained 6% sucrose (control) or 6% sucrose supplemented with (1) tryptophan (3 g l-1), (2) a low dose of BCAA (6 g l-1......) or (3) a high dose of BCAA (18 g l-1). 2. These treatments greatly increased the plasma concentration of the respective amino acids. Using the kinetic parameters of transport of human brain capillaries, BCAA supplements were estimated to reduce brain tryptophan uptake at exhaustion by 8-12%, while...

  9. YjeH Is a Novel Exporter of l-Methionine and Branched-Chain Amino Acids in Escherichia coli.

    Science.gov (United States)

    Liu, Qian; Liang, Yong; Zhang, Yun; Shang, Xiuling; Liu, Shuwen; Wen, Jifu; Wen, Tingyi

    2015-11-01

    Amino acid efflux transport systems have important physiological functions and play vital roles in the fermentative production of amino acids. However, no methionine exporter has yet been identified in Escherichia coli. In this study, we identified a novel amino acid exporter, YjeH, in E. coli. The yjeH overexpression strain exhibited high tolerance to the structural analogues of l-methionine and branched-chain amino acids, decreased intracellular amino acid levels, and enhanced export rates in the presence of a Met-Met, Leu-Leu, Ile-Ile, or Val-Val dipeptide, suggesting that YjeH functions as an exporter of l-methionine and the three branched-chain amino acids. The export of the four amino acids in the yjeH overexpression strain was competitively inhibited in relation to each other. The expression of yjeH was strongly induced by increasing cytoplasmic concentrations of substrate amino acids. Green fluorescent protein (GFP)-tagged YjeH was visualized by total internal reflection fluorescence microscopy to confirm the plasma membrane localization of YjeH. Phylogenetic analysis of transporters indicated that YjeH belongs to the amino acid efflux family of the amino acid/polyamine/organocation (APC) superfamily. Structural modeling revealed that YjeH has the typical "5 + 5" transmembrane α-helical segment (TMS) inverted-repeat fold of APC superfamily transporters, and its binding sites are strictly conserved. The enhanced capacity of l-methionine export by the overexpression of yjeH in an l-methionine-producing strain resulted in a 70% improvement in titer. This study supplements the transporter classification and provides a substantial basis for the application of the methionine exporter in metabolic engineering.

  10. Synthesis and aggregation behavior of 2-(4-butyloctyl) malonic acid in aqueous solution. The formation of physically and colloidally stable vesicles by a branched-chain malonate

    NARCIS (Netherlands)

    Groot, Rimke W. de; Wagenaar, Anno; Sein, Arjen; Engberts, Jan B.F.N.

    1995-01-01

    A new surfactant with a branched monoalkyl chain and a malonate headgroup has been synthesized: 2-(4-butyloctyl)malonic acid (BOMA). From the geometry of the surfactant, reflected in a packing parameter (P), it was anticipated that the surfactant would preferably aggregate in bilayers. This expectat

  11. In vitro transcriptional studies of the bkd operon of Pseudomonas putida: L-branched-chain amino acids and D-leucine are the inducers.

    Science.gov (United States)

    Madhusudhan, K T; Luo, J; Sokatch, J R

    1999-05-01

    BkdR is the transcriptional activator of the bkd operon, which encodes the four proteins of the branched-chain keto acid dehydrogenase multienzyme complex of Pseudomonas putida. In this study, hydroxyl radical footprinting revealed that BkdR bound to only one face of DNA over the same region identified in DNase I protection assays. Deletions of even a few bases in the 5' region of the BkdR-binding site greatly reduced transcription, confirming that the entire protected region is necessary for transcription. In vitro transcription of the bkd operon was obtained by using a vector containing the bkdR-bkdA1 intergenic region plus the putative rho-independent terminator of the bkd operon. Substrate DNA, BkdR, and any of the L-branched-chain amino acids or D-leucine was required for transcription. Branched-chain keto acids, D-valine, and D-isoleucine did not promote transcription. Therefore, the L-branched-chain amino acids and D-leucine are the inducers of the bkd operon. The concentration of L-valine required for half-maximal transcription was 2.8 mM, which is similar to that needed to cause half-maximal proteolysis due to a conformational change in BkdR. A model for transcriptional activation of the bkd operon by BkdR during enzyme induction which incorporates these results is presented. PMID:10217783

  12. Branched-chain amino acids increase arterial blood ammonia in spite of enhanced intrinsic muscle ammonia metabolism in patients with cirrhosis and healthy subjects

    DEFF Research Database (Denmark)

    Dam, Gitte; Keiding, Susanne; Munk, Ole Lajord;

    2011-01-01

    Branched-chain amino acids (BCAA) are used in attempts to reduce blood ammonia in patients with cirrhosis and intermittent hepatic encephalopathy based on the hypothesis that BCAA stimulate muscle ammonia detoxification. We studied the effects of an oral dose of BCAA on the skeletal muscle metabo...

  13. Rumen odd and branched chain fatty acids in relation to in vitro rumen volatile fatty acid productions and dietary characteristics of incubated substrates

    NARCIS (Netherlands)

    Vlaeminck, B.; Fievez, V.; Laar, van H.; Demeyer, D.

    2004-01-01

    A first aim of this batch in vitro experiment (21 h) was to use changes in odd and branched chain fatty acid (OBCFA) patterns to suggest shifts in microbial populations, associated with four types of incubated whole dairy cow diets. Principal component analysis suggested higher dietary starch increa

  14. Isovaleryl-homoserine lactone, an unusual branched-chain quorum-sensing signal from the soybean symbiont Bradyrhizobium japonicum.

    Science.gov (United States)

    Lindemann, Andrea; Pessi, Gabriella; Schaefer, Amy L; Mattmann, Margrith E; Christensen, Quin H; Kessler, Aline; Hennecke, Hauke; Blackwell, Helen E; Greenberg, E Peter; Harwood, Caroline S

    2011-10-01

    Many species of Proteobacteria communicate by using LuxI-LuxR-type quorum-sensing systems that produce and detect acyl-homoserine lactone (acyl-HSL) signals. Most of the known signals are straight-chain fatty acyl-HSLs, and evidence indicates that LuxI homologs prefer fatty acid-acyl carrier protein (ACP) over fatty acyl-CoA as the acyl substrate for signal synthesis. Two related LuxI homologs, RpaI and BtaI from Rhodopseudomonas palustris and photosynthetic stem-nodulating bradyrhizobia, direct production of the aryl-HSLs p-coumaroyl-HSL and cinnamoyl-HSL, respectively. Here we report that BjaI from the soybean symbiont Bradyrhizobium japonicum USDA110 is closely related to RpaI and BtaI and catalyzes the synthesis of isovaleryl-HSL (IV-HSL), a branched-chain fatty acyl-HSL. We show that IV-HSL induces expression of bjaI, and in this way IV-HSL functions like many other acyl-HSL quorum-sensing signals. Purified histidine-tagged BjaI was an IV-HSL synthase, which was active with isovaleryl-CoA but not detectably so with isovaleryl-ACP. This suggests that the RpaI-BtaI-BjaI subfamily of acyl-HSL synthases may use CoA- rather than ACP-linked substrates for acyl-HSL synthesis. The bjaI-linked bjaR(1) gene is involved in the response to IV-HSL, and BjaR(1) is sensitive to IV-HSL at concentrations as low as 10 pM. Low but sufficient levels of IV-HSL (about 5 nM) accumulate in B. japonicum culture fluid. The low levels of IV-HSL synthesis have likely contributed to the fact that the quorum-sensing signal from this bacterium has not been described elsewhere.

  15. The Supplementation of Branched-Chain Amino Acids, Arginine, and Citrulline Improves Endurance Exercise Performance in Two Consecutive Days

    Directory of Open Access Journals (Sweden)

    I-Shiung Cheng, Yi-Wen Wang, I-Fan Chen, Gi-Sheng Hsu, Chun-Fang Hsueh, Chen-Kang Chang

    2016-09-01

    Full Text Available The central nervous system plays a crucial role in fatigue during endurance exercise. Branched-chain amino acids (BCAA could reduce cerebral serotonin synthesis by competing with its precursor tryptophan for crossing the blood brain barrier. Arginine and citrulline could prevent excess hyperammonemia accompanied by BCAA supplementation. This study investigated the combination of BCAA, arginine, and citrulline on endurance performance in two consecutive days. Seven male and three female endurance runners ingested 0.17 g·kg-1 BCAA, 0.05 g·kg-1 arginine and 0.05 g·kg-1 citrulline (AA trial or placebo (PL trial in a randomized cross-over design. Each trial contained a 5000 m time trial on the first day, and a 10000 m time trial on the second day. The AA trial had significantly better performance in 5000 m (AA: 1065.7 ± 33.9 s; PL: 1100.5 ± 40.4 s and 10000 m (AA: 2292.0 ± 211.3 s; PL: 2375.6 ± 244.2 s. The two trials reported similar ratings of perceived exertion. After exercise, the AA trial had significantly lower tryptophan/BCAA ratio, similar NH3, and significantly higher urea concentrations. In conclusion, the supplementation could enhance time-trial performance in two consecutive days in endurance runners, possibly through the inhibition of cerebral serotonin synthesis by BCAA and the prevention of excess hyperammonemia by increased urea genesis.

  16. Branched-chain amino acids to tyrosine ratio value as a potential prognostic factor for hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Toru Ishikawa

    2012-01-01

    The prognosis of hepatocellular carcinoma (HCC) depends on tumor extension as well as hepatic function.Hepatic functional reserve is recognized as a factor affecting survival in the treatment of HCC; the ChildPugh classification system is the most extensively used method for assessing hepatic functional reserve in patients with chronic liver disease,using serum albumin level to achieve accurate assessment of the status of protein metabolism.However,insufficient attention has been given to the status of amino acid (AA) metabolism in chronic liver disease and HCC.Fischer's ratio is the molar ratio of branched-chain AAs (BCAAs:leucine,valine,isoleucine) to aromatic AAs (phenylalanine,tyrosine) and is important for assessing liver metabolism,hepatic functional reserve and the severity of liver dysfunction.Although this ratio is difficult to determine in clinical situations,BCAAs/tyrosine molar concentration ratio (BTR) has been proposed as a simpler substitute.BTR correlates with various liver function examinations,including markers of hepatic fibrosis,hepatic blood flow and hepatocyte function,and can thus be considered as reflecting the degree of hepatic impairment.This manuscript examines the literature to clarify whether BTR can serve as a prognostic factor for treatment of HCC.

  17. Branched-Chain Amino Acids as New Biomarkers of Major Depression - A Novel Neurobiology of Mood Disorder

    Science.gov (United States)

    Baranyi, Andreas; Amouzadeh-Ghadikolai, Omid; von Lewinski, Dirk; Rothenhäusler, Hans-Bernd; Theokas, Simon; Robier, Christoph; Mangge, Harald; Reicht, Gerhard; Hlade, Peter; Meinitzer, Andreas

    2016-01-01

    Background The proteinogenic branched-chain amino acids (BCAAs) valine, leucine and isoleucine might play an unrecognised crucial role in the development of depression through their activation of the mammalian target of rapamycin (mTor) pathway. The aim of this research project is to evaluate whether BCAAs are altered in patients with major depression and might thus be appropriate biomarkers for major depression. Methods The concentrations of valine, leucine and isoleucine were determined in 71 in-patients with major depression and 48 healthy controls by high-pressure liquid chromatography. Psychiatric and laboratory assessments were obtained at the time of in-patient admittance. Results The BCAAs are significantly decreased in patients with major depression in comparison with healthy subjects (valine: Mann-Whitney-U: 968.0; p Inventory (BDI-II) scores. Conclusions Our study results are strong evidence that in patients with major depression, BCAAs might be appropriate biomarkers for depression. Reduced activation of the mammalian target of rapamycin (mTor) due to a reduction of BCAAs might play a crucial unrecognised factor in the etiology of depression and may evoke depressive symptomatology and lower energy metabolism in patients with major depression. In the future, mTor and its up- and downstream signalling partners might be important targets for the development of novel antidepressants. PMID:27490818

  18. Branched-chain amino acid supplementation does not enhance athletic performance but affects muscle recovery and the immune system.

    Science.gov (United States)

    Negro, M; Giardina, S; Marzani, B; Marzatico, F

    2008-09-01

    Since the 1980's there has been high interest in branched-chain amino acids (BCAA) by sports nutrition scientists. The metabolism of BCAA is involved in some specific biochemical muscle processes and many studies have been carried out to understand whether sports performance can be enhanced by a BCAA supplementation. However, many of these researches have failed to confirm this hypothesis. Thus, in recent years investigators have changed their research target and focused on the effects of BCAA on the muscle protein matrix and the immune system. Data show that BCAA supplementation before and after exercise has beneficial effects for decreasing exercise-induced muscle damage and promoting muscle-protein synthesis. Muscle damage develops delayed onset muscle soreness: a syndrome that occurs 24-48 h after intensive physical activity that can inhibit athletic performance. Other recent works indicate that BCAA supplementation recovers peripheral blood mononuclear cell proliferation in response to mitogens after a long distance intense exercise, as well as plasma glutamine concentration. The BCAA also modifies the pattern of exercise-related cytokine production, leading to a diversion of the lymphocyte immune response towards a Th1 type. According to these findings, it is possible to consider the BCAA as a useful supplement for muscle recovery and immune regulation for sports events. PMID:18974721

  19. The influence of alternative pathways of respiration that utilize branched-chain amino acids following water shortage in Arabidopsis.

    Science.gov (United States)

    Pires, Marcel V; Pereira Júnior, Adilson A; Medeiros, David B; Daloso, Danilo M; Pham, Phuong Anh; Barros, Kallyne A; Engqvist, Martin K M; Florian, Alexandra; Krahnert, Ina; Maurino, Veronica G; Araújo, Wagner L; Fernie, Alisdair R

    2016-06-01

    During dark-induced senescence isovaleryl-CoA dehydrogenase (IVDH) and D-2-hydroxyglutarate dehydrogenase (D-2HGDH) act as alternate electron donors to the ubiquinol pool via the electron-transfer flavoprotein/electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF/ETFQO) pathway. However, the role of this pathway in response to other stresses still remains unclear. Here, we demonstrated that this alternative pathway is associated with tolerance to drought in Arabidopsis. In comparison with wild type (WT) and lines overexpressing D-2GHDH, loss-of-function etfqo-1, d2hgdh-2 and ivdh-1 mutants displayed compromised respiration rates and were more sensitive to drought. Our results demonstrated that an operational ETF/ETFQO pathway is associated with plants' ability to withstand drought and to recover growth once water becomes replete. Drought-induced metabolic reprogramming resulted in an increase in tricarboxylic acid (TCA) cycle intermediates and total amino acid levels, as well as decreases in protein, starch and nitrate contents. The enhanced levels of the branched-chain amino acids in loss-of-function mutants appear to be related to their increased utilization as substrates for the TCA cycle under water stress. Our results thus show that mitochondrial metabolism is highly active during drought stress responses and provide support for a role of alternative respiratory pathways within this response.

  20. INVERSION SYMMETRY, ARCHITECTURE AND DISPERSITY, AND THEIR EFFECTS ON THERMODYNAMICS IN BULK AND CONFINED REGIONS: FROM RANDOMLY BRANCHED POLYMERS TO LINEAR CHAINS, STARS AND DENDRIMERS

    Directory of Open Access Journals (Sweden)

    P.D.Gujrati

    2002-01-01

    Full Text Available Theoretical evidence is presented in this review that architectural aspects can play an important role, not only in the bulk but also in confined geometries by using our recursive lattice theory, which is equally applicable to fixed architectures (regularly branched polymers, stars, dendrimers, brushes, linear chains, etc. and variable architectures, i.e. randomly branched structures. Linear chains possess an inversion symmetry (IS of a magnetic system (see text, whose presence or absence determines the bulk phase diagram. Fixed architectures possess the IS and yield a standard bulk phase diagram in which there exists a theta point at which two critical lines C and C' meet and the second virial coefficient A2 vanishes. The critical line C appears only for infinitely large polymers, and an order parameter is identified for this criticality. The critical line C' exists for polymers of all sizes and represents phase separation criticality. Variable architectures, which do not possess the IS, give rise to a topologically different phase diagram with no theta point in general. In confined regions next to surfaces, it is not the IS but branching and monodispersity, which becomes important in the surface regions. We show that branching plays no important role for polydisperse systems, but become important for monodisperse systems. Stars and linear chains behave differently near a surface.

  1. Usefulness of Levocarnitine and/or Branched-Chain Amino Acids during Invasive Treatment for Hepatocellular Carcinoma.

    Science.gov (United States)

    Iwasa, Motoh; Sugimoto, Ryosuke; Ishihara, Tomoaki; Sekoguchi-Fujikawa, Noriko; Yoshikawa, Kyoko; Mifuji-Moroka, Rumi; Tanaka, Hideaki; Kobayashi, Yoshinao; Hasegawa, Hiroshi; Takei, Yoshiyuki

    2015-01-01

    Transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) are effective treatments for hepatocellular carcinoma (HCC). However, the extent of treatment depends on hepatic functional reserve. L-Carnitine is a vitamin-like substance and several reports have described the usefulness of L-carnitine supplementation in cases of cirrhosis, with confirmed effectiveness against refractory hepatic encephalopathy. On the other hand, we have previously reported that in patients who underwent TACE or RFA, administration of branched-chain amino acids (BCAAs) pre-intervention significantly reduced inflammatory reactions. We first determined serum levels of total, free, and acyl-carnitine before and at 7 d after performing TACE in 10 HCC patients. We administered levocarnitine (L-carnitine chloride, a biologically active form of carnitine) at 900 mg/d to 69 consecutive HCC patients hospitalized to undergo TACE and/or RFA, and compared changes in blood test values with those in 119 consecutive patients not administered this drug. Sixty-seven patients had a history of using BCAAs at the time of admission. We found that after 7 d of TACE, serum levels of total and acyl-carnitine are significantly decreased. On comparing the four groups, the carnitine+BCAA, carnitine-alone, and BCAA-alone groups showed significantly higher values for changes in NH3 when compared with the non-dosed group. The decrease in albumin (Alb) was significantly suppressed in the carnitine+BCAA and BCAA-alone groups. We also conducted the same examinations in a subset of patients classified as Child-Pugh class A, and noted the same trends. Administration of levocarnitine and/or BCAAs during invasive treatments reduced blood NH3 concentrations and suppressed decreases in Alb. PMID:26875483

  2. Branched-Chain Amino Acids as New Biomarkers of Major Depression - A Novel Neurobiology of Mood Disorder

    Science.gov (United States)

    Baranyi, Andreas; Amouzadeh-Ghadikolai, Omid; von Lewinski, Dirk; Rothenhäusler, Hans-Bernd; Theokas, Simon; Robier, Christoph; Mangge, Harald; Reicht, Gerhard; Hlade, Peter; Meinitzer, Andreas

    2016-01-01

    Background The proteinogenic branched-chain amino acids (BCAAs) valine, leucine and isoleucine might play an unrecognised crucial role in the development of depression through their activation of the mammalian target of rapamycin (mTor) pathway. The aim of this research project is to evaluate whether BCAAs are altered in patients with major depression and might thus be appropriate biomarkers for major depression. Methods The concentrations of valine, leucine and isoleucine were determined in 71 in-patients with major depression and 48 healthy controls by high-pressure liquid chromatography. Psychiatric and laboratory assessments were obtained at the time of in-patient admittance. Results The BCAAs are significantly decreased in patients with major depression in comparison with healthy subjects (valine: Mann-Whitney-U: 968.0; p <0.0001, leucine: Mann-Whitney-U: 1246.5; p = 0.013, isoleucine: Mann-Whitney-U: 1252.5; p = 0.014). Furthermore, as shown by Spearman's rank correlation coefficients, there is a significant negative correlation between valine, leucine and isoleucine concentrations and the Hamilton Depression Rating Scale (HAMD-17) as well as Beck Depression Inventory (BDI-II) scores. Conclusions Our study results are strong evidence that in patients with major depression, BCAAs might be appropriate biomarkers for depression. Reduced activation of the mammalian target of rapamycin (mTor) due to a reduction of BCAAs might play a crucial unrecognised factor in the etiology of depression and may evoke depressive symptomatology and lower energy metabolism in patients with major depression. In the future, mTor and its up- and downstream signalling partners might be important targets for the development of novel antidepressants. PMID:27490818

  3. Transient overshoot extensional rheology of long-chain branched polyethylenes: Experimental and numerical comparisons between filament stretching and cross-slot flow

    DEFF Research Database (Denmark)

    Hoyle, D.M.; Huang, Qian; Auhl, D.;

    2013-01-01

    This work analyses the high-strain extensional behavior of long-chain branched polyethylenes, employing two novel extensional rheometer devices, the filament stretching rheometer and the cross-slot extensional rheometer. The filament stretching rheometer uses an active feedback loop to control...... the imposed strain rate on a filament, allowing Hencky strains of around 7 to be reached. The cross-slot extensional rheometer uses optical birefringence patterns to determine the steady-state extensional viscosity from planar stagnation point flow. The two methods probe different strain-rate regimes...... and in this paper we demonstrate the agreement when the operating regimes overlap and explore the steady-state extensional viscosity in the full strain-rate regime that these two complimentary techniques offer. For long-chain branched materials, the cross-slot birefringence images show a double cusp pattern around...

  4. Valine, a Branched-Chain Amino Acid, Reduced HCV Viral Load and Led to Eradication of HCV by Interferon Therapy in a Decompensated Cirrhotic Patient

    OpenAIRE

    Kawaguchi, Takumi; Torimura, Takuji; Takata, Akio; Satomi, Susumu; Sata, Michio

    2012-01-01

    A decreased serum level of branched-chain amino acid (BCAA) is a distinctive metabolic disorder in patients with liver cirrhosis. Recently, BCAA has been reported to exert various pharmacological activities, and valine, which is a BCAA, has been shown to affect lipid metabolism and the immune system in in vivo experiments. However, the clinical impact of valine supplementation on viral hepatitis C virus (HCV) load has never been reported. Here, we first describe a case of HCV-related advanced...

  5. Branched-chain amino acids, arginine, citrulline alleviate central fatigue after 3 simulated matches in taekwondo athletes: a randomized controlled trial

    OpenAIRE

    Chen, I-Fan; Wu, Huey-June; Chen, Chung-Yu; Chou, Kuei-Ming; Chang, Chen-Kang

    2016-01-01

    Background The decline in cognitive performance has been shown after fatiguing exercise. Branched-chain amino acids (BCAA) have been suggested to alleviate exercise-induced central fatigue. Arginine and citrulline could remove the excess NH3 accumulation accompanied with BCAA supplementation by increasing nitric oxide biosynthesis and/or urea cycle. The purpose of this study is to investigate the effect of the combined supplementation of BCAA, arginine, and citrulline on central fatigue after...

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

    Energy Technology Data Exchange (ETDEWEB)

    Tremblay, L.; Blanchard, J

    2009-01-01

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

  7. Postruminal synthesis modifies the odd- and branched-chain fatty acid profile from the duodenum to milk.

    Science.gov (United States)

    Vlaeminck, B; Gervais, R; Rahman, M M; Gadeyne, F; Gorniak, M; Doreau, M; Fievez, V

    2015-07-01

    Milk odd- and branched-chain fatty acids (OBCFA) have been suggested as potential biomarkers for rumen function. The potential of milk OBCFA as a biomarker depends on whether their profile reflects the profile observed in the duodenum. The objective of this study was to evaluate whether the OBCFA profile in duodenum samples is reflected in plasma and milk. For this, 2 dairy cattle experiments were used. In experiment 1, 4 Holstein cows fitted with rumen and proximal duodenum cannulas were used in a 4×4 Latin square design. The treatments consisted of 2 nitrogen levels (143 vs. 110g of crude protein/kg of dry matter for high and low N, respectively) combined with either 1 of the 2 energy sources (i.e., starch from barley, corn, and wheat or fiber from soybean hulls and dehydrated beet pulp). In experiment 2, 4 Holstein cows fitted with rumen and proximal duodenum cannulas were used in a 3×3 Latin square design, with the treatments consisting of 3 diets: (1) RNB-, a diet with a crude protein content of 122g/kg of dry matter, predicted to provide protein digested in the small intestine according to the requirement of the animals, but with a shortage of rumen degradable protein; (2) RNB- to which 6g/d of niacin was added through inclusion in the mineral and vitamin premix, and (3) RNB- to which urea was added to balance rumen degradable N supply resulting in a CP content of 156g/kg of dry matter. In both experiments, samples of duodenal digesta, plasma, and milk were collected and analyzed for fatty acids. Additionally, lipids in plasma samples were separated in lipid classes and analyzed for fatty acids. The OBCFA profile in milk was enriched in 15:0, iso-17:0, anteiso-17:0, and cis-9-17:1 as compared with duodenal samples, and milk secretions even exceeded duodenal flows, which suggests occurrence of postruminal synthesis, such as de novo synthesis, desaturation, and elongation. The postruminal modification of the OBCFA profile might hamper the application of OBCFA

  8. The influence of environmental parameters on the catabolism of branched-chain amino acids by Staphylococcus xylosus and Staphylococcus carnosus

    DEFF Research Database (Denmark)

    Olesen, Pelle Thonning; Stahnke, Louise Heller

    2004-01-01

    Degradation of the amino acids leucine, isoleucine and valine into branched flavour compounds by Staphylococcus xylosus and Staphylococcus carnosus was studied using resting cell cultures added to a defined reaction medium under different environmental conditions relevant to sausage fermentation...... detection (GC/FID). Main volatile catabolic products of leucine, isoleucine and valine were 3-methylbutanoic, 2-methylbutanoic and 2-methylpropanoic acids, respectively. The generation of branched flavour compounds was influenced significantly by most of the investigated environmental parameters...

  9. Determination of rate constants and branching ratios for TCE degradation by zero-valent iron using a chain decay multispecies model

    Science.gov (United States)

    Hwang, Hyoun-Tae; Jeen, Sung-Wook; Sudicky, Edward A.; Illman, Walter A.

    2015-06-01

    The applicability of a newly-developed chain-decay multispecies model (CMM) was validated by obtaining kinetic rate constants and branching ratios along the reaction pathways of trichloroethene (TCE) reduction by zero-valent iron (ZVI) from column experiments. Changes in rate constants and branching ratios for individual reactions for degradation products over time for two columns under different geochemical conditions were examined to provide ranges of those parameters expected over the long-term. As compared to the column receiving deionized water, the column receiving dissolved CaCO3 showed higher mean degradation rates for TCE and all of its degradation products. However, the column experienced faster reactivity loss toward TCE degradation due to precipitation of secondary carbonate minerals, as indicated by a higher value for the ratio of maximum to minimum TCE degradation rate observed over time. From the calculated branching ratios, it was found that TCE and cis-dichloroethene (cis-DCE) were dominantly dechlorinated to chloroacetylene and acetylene, respectively, through reductive elimination for both columns. The CMM model, validated by the column test data in this study, provides a convenient tool to determine simultaneously the critical design parameters for permeable reactive barriers and natural attenuation such as rate constants and branching ratios.

  10. Xanthomonas campestris FabH is required for branched-chain fatty acid and DSF-family quorum sensing signal biosynthesis.

    Science.gov (United States)

    Yu, Yong-Hong; Hu, Zhe; Dong, Hui-Juan; Ma, Jin-Cheng; Wang, Hai-Hong

    2016-01-01

    Xanthomonas campestris pv. campestris (Xcc), a Gram-negative phytopathogenic bacterium, causes black rot disease of cruciferous vegetables. Although Xcc has a complex fatty acid profile comprised of straight-chain fatty acids and branched-chain fatty acids (BCFAs), and encodes a complete set of genes required for fatty acid synthesis, there is still little known about the mechanism of BCFA synthesis. We reported that expression of Xcc fabH restores the growth of Ralstonia solanacearum fabH mutant, and this allows the R. solanacearum fabH mutant to produce BCFAs. Using in vitro assays, we demonstrated that Xcc FabH is able to condense branched-chain acyl-CoAs with malonyl-ACP to initiate BCFA synthesis. Moreover, although the fabH gene is essential for growth of Xcc, it can be replaced with Escherichia coli fabH, and Xcc mutants failed to produce BCFAs. These results suggest that Xcc does not have an obligatory requirement for BCFAs. Furthermore, Xcc mutants lost the ability to produce cis-11-methyl-2-dodecenoic acid, a diffusible signal factor (DSF) required for quorum sensing of Xcc, which confirms that the fatty acid synthetic pathway supplies the intermediates for DSF signal biosynthesis. Our study also showed that replacing Xcc fabH with E. coli fabH affected Xcc pathogenesis in host plants. PMID:27595587

  11. Direct determination of flavor relevant and further branched-chain fatty acids from sheep subcutaneous adipose tissue by gas chromatography with mass spectrometry.

    Science.gov (United States)

    Kaffarnik, Stefanie; Preuß, Siegfried; Vetter, Walter

    2014-07-11

    4-Methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid are key-flavor compounds of sheep and goat. Yet, the low amounts of these volatile branched-chain fatty acids (vBCFAs) in the fat of the ruminants hampered their determination on a routine basis. In this work we developed a gas chromatography/mass spectrometry selected ion monitoring (GC/MS-SIM) method for the direct determination of the vBCFAs as methyl esters, which were obtained after transesterification of subcutaneous adipose tissue of sheep. The excellent sensitivity of the GC/MS-SIM method (limit of quantification, LOQ, 3.6-4.8μg/g; limit of detection, LOD, 1.1-1.4μg/g for 4-Me-8:0, 4-Et-8:0 and 4-Me-9:0) enabled us to determine the three vBCFAs without an enrichment step. Subcutaneous adipose sheep tissue of three different breeds contained 23-88μg/g 4-methyloctanoic acid, 13-26μg/g 4-ethyloctanoic acid and ∼2.9-18μg/g 4-methylnonanoic acid. Since all fatty acids were present in the FAME fraction, the samples could be screened for further branched-chain FAMEs. After elimination of unsaturated fatty acids by hydrogenation (the presence of some unsaturated fatty acids could be verified by this measure), additional measurements in SIM and full scan modes of methyl esters and picolinyl esters enabled the determination of further 97 saturated fatty acids in the samples with eight to 20 carbons. The method is suited for routine analysis and may be useful to investigate the reasons for the abundance/absence of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid and further branched-chain fatty acids in sheep and goat.

  12. Effects of leucine supplementation and serum withdrawal on branched-chain amino acid pathway gene and protein expression in mouse adipocytes.

    Directory of Open Access Journals (Sweden)

    Abderrazak Kitsy

    Full Text Available The essential branched-chain amino acids (BCAA, leucine, valine and isoleucine, are traditionally associated with skeletal muscle growth and maintenance, energy production, and generation of neurotransmitter and gluconeogenic precursors. Recent evidence from human and animal model studies has established an additional link between BCAA levels and obesity. However, details of the mechanism of regulation of BCAA metabolism during adipogenesis are largely unknown. We interrogated whether the expression of genes and proteins involved in BCAA metabolism are sensitive to the adipocyte differentiation process, and responsive to nutrient stress from starvation or BCAA excess. Murine 3T3-L1 preadipocytes were differentiated to adipocytes under control conditions and under conditions of L-leucine supplementation or serum withdrawal. RNA and proteins were isolated at days 0, 4 and 10 of differentiation to represent pre-differentiation, early differentiation and late differentiation stages. Expression of 16 BCAA metabolism genes was quantified by quantitative real-time PCR. Expression of the protein levels of branched-chain amino acid transaminase 2 (Bcat2 and branched-chain alpha keto acid dehydrogenase (Bckdha was quantified by immunoblotting. Under control conditions, all genes displayed induction of gene expression during early adipogenesis (Day 4 compared to Day 0. Leucine supplementation resulted in an induction of Bcat2 and Bckdha genes during early and late differentiation. Western blot analysis demonstrated condition-specific concordance between gene and protein expression. Serum withdrawal resulted in undetectable Bcat2 and Bckdha protein levels at all timepoints. These results demonstrate that the expression of genes related to BCAA metabolism are regulated during adipocyte differentiation and influenced by nutrient levels. These results provide additional insights on how BCAA metabolism is associated with adipose tissue function and extends our

  13. Branched-chain amino acid requirements for enterally fed term neonates in the first month of life

    NARCIS (Netherlands)

    F. Maingay-de Groof (Femke); L. Huang; I. van Vliet (Ineke); G.J. Voortman (Gardi); H. Schierbeek (Henk); L.C.W. Roksnoer (Lodi); A. Vermes (Andras); C. Chen (Chao); Y. Huang (Ying); J.B. van Goudoever (Hans)

    2014-01-01

    textabstractBackground: Knowledge of essential amino acid requirements in infants is important because excessive intake of protein can lead to increased long-term morbidity such as obesity. A deficient intake may lead to suboptimal growth and impaired neurodevelopment. The current recommended branch

  14. In Vitro Transcriptional Studies of the bkd Operon of Pseudomonas putida: l-Branched-Chain Amino Acids and d-Leucine Are the Inducers

    OpenAIRE

    Madhusudhan, Kunapuli T.; Luo, Jinhe; Sokatch, John R.

    1999-01-01

    BkdR is the transcriptional activator of the bkd operon, which encodes the four proteins of the branched-chain keto acid dehydrogenase multienzyme complex of Pseudomonas putida. In this study, hydroxyl radical footprinting revealed that BkdR bound to only one face of DNA over the same region identified in DNase I protection assays. Deletions of even a few bases in the 5′ region of the BkdR-binding site greatly reduced transcription, confirming that the entire protected region is necessary for...

  15. Effects of Diets Supplemented with Branched-Chain Amino Acids on the Performance and Fatigue Mechanisms of Rats Submitted to Prolonged Physical Exercise

    OpenAIRE

    Inar Alves Castro; Eivor Martins Junior; Rogério Graça Pedrosa; Ivanir Santana de Oliveira Pires; Marcelo Macedo Rogero; Jonas Alves de Araújo Junior; Gina Falavigna; Julio Tirapegui

    2012-01-01

    This study aimed to determine the effects of diets chronically supplemented with branched-chain amino acids (BCAA) on the fatigue mechanisms of trained rats. Thirty-six adult Wistar rats were trained for six weeks. The training protocol consisted of bouts of swimming exercise (one hour a day, five times a week, for six weeks). The animals received a control diet (C) (n = 12), a diet supplemented with 3.57% BCAA (S1) (n = 12), or a diet supplemented with 4.76% BCAA (S2) (n = 12). On the last d...

  16. Evaluation of branched chain fatty acid, BMIPP (. beta. -methyl-. omega. -(p-iodophenyl)-pentadecanoic acid) for the myocardial imaging. Basic experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kawamura, Yasuaki; Morishita, Takeshi; Yamazaki, Junichi and others

    1988-11-01

    Iodine-123 labeled branched chain fatty acid BMIPP (/sup ..beta../-methyl-..omega..-(p-iodophenyl)-pentadecanoic acid) was evaluated for the myocardial imaging experimentally. /sup 123/I-BMIPP was accumulated in the heart at 2 - 4 minutes after injection and retention in the heart was remarkable at 30 minutes. In the acute canine infarction model, infarcted area was recognized as a defect. Furthermore, in comparison between /sup 123/I-BMIPP and /sup 201/Tl-Cl, discrepancy between these images was recognized in the ischemic and infarcted area. BMIPP is of use in not only cardiomyopathy and hypertension, but ischemic heart desease.

  17. Alpha-decay branching ratios to high-lying excited-states of the 242Cm→238pu→ 234U →230Th→226Rn decay chain

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jin-Juan; XU Chang; REN Zhong-Zhou

    2009-01-01

    We present a systematic calculation on the 0c-decay branching ratios to excited-states of an even-even α-decay chain 242Cm→238pu→234U →230Th→226Rn by the improved barrier penetration approach. The changes of the parities between the parent nuclei and the daughter nuclei are properly taken into account. The theoretical values are compared with the available experimental data and the deviation between them is within a factor of 5 in most cases.

  18. Low half-wave voltage Y-branch electro-optic polymer modulator based on side-chain polyurethane-imide

    Science.gov (United States)

    Tang, Jie; Wang, Long-De; Li, Ruo-Zhou; Zhang, Qiang; Zhang, Tong

    2016-06-01

    A Y-branch electro-optic (EO) polymer modulator has been designed and fabricated. High performance side-chain polyurethane-imide (PUI) with a high EO coefficient of larger than 50 pm/V and a moderate glass-transition temperature (Tg) of 206∘C is used as EO polymer core layer of the modulator. The fabricated phase modulator exhibits a low half-wave voltage of 1.94 V at 1550 nm in single arm modulation with 1 cm EO interaction length and 2 cm total length. The results show that the modulator fabricated by side-chain PUI EO materials possesses potential applications in low driving voltage and low cost optical systems.

  19. Branched chain enriched amino acid versus glucose treatment of hepatic encephalopathy. A double-blind study of 65 patients with cirrhosis

    DEFF Research Database (Denmark)

    Vilstrup, Hendrik; Gluud, C; Hardt, F;

    1990-01-01

    . In the glucose group ten died, three developed renal and two respiratory failure, and one remained encephalopathic. The coma score worsened in three of the patients who died in the amino acid group, but in all patients who died in the glucose group. The negative nitrogen balance on entry reversed in the amino......We studied the effects of infusion of a branched chain enriched amino acid mixture versus glucose on acute hepatic encephalopathy in patients with cirrhosis. Sixty-five patients were randomly treated with 1 g/kg per day of an amino acid mixture with 40% branched chain contents (32 patients......), or isocaloric glucose (33 patients) for a maximum of 16 days. The regimens further included glucose infusion to a total of 26.5 kcal/kg per day and lactulose. The patients took part in the study for 5-6 days. In each group 17 patients woke up. In the amino acid group eleven died and four developed renal failure...

  20. Solid-State Organization and Ambipolar Field-Effect Transistors of Benzothiadiazole-Cyclopentadithiophene Copolymer with Long Branched Alkyl Side Chains

    Directory of Open Access Journals (Sweden)

    Martin Baumgarten

    2013-06-01

    Full Text Available The solid-state organization of a benzothiadiazole-cyclopentadithiophene copolymer with long, branched decyl-tetradecyl side chains (CDT-BTZ-C14,10 is investigated. The C14,10 substituents are sterically demanding and increase the π-stacking distance to 0.40 nm from 0.37 nm for the same polymer with linear hexadecyls (C16. Despite the bulkiness, the C14,10 side chains tend to crystallize, leading to a small chain-to-chain distance between lamellae stacks and to a crystal-like microstructure in the thin film. Interestingly, field-effect transistors based on solution processed layers of CDT-BTZ-C14,10 show ambipolar behavior in contrast to CDT-BTZ-C16 with linear side chains, for which hole transport was previously observed. Due to the increased π-stacking distance, the mobilities are only 6 × 10−4 cm²/Vs for electrons and 6 × 10−5 cm²/Vs for holes, while CDT-BTZ-C16 leads to values up to 5.5 cm²/Vs. The ambipolarity is attributed to a lateral shift between stacked backbones provoked by the bulky C14,10 side chains. This reorganization is supposed to change the transfer integrals between the C16 and C14,10 substituted polymers. This work shows that the electronic behavior in devices of one single conjugated polymer (in this case CDT-BTZ can be controlled by the right choice of the substituents to place the backbones in the desired packing.

  1. Shock tube measurements of growth constants in the branched-chain ethane-carbon monoxide-oxygen system

    Science.gov (United States)

    Brokaw, R. S.; Brabbs, T. A.; Snyder, C. A.

    1985-01-01

    Exponential free radical growth constants have been measured for ethane carbon monoxide oxygen mixtures by monitoring the growth of oxygen atom concentration as manifested by CO flame band emission. Data were obtained over the temperature range of 1200 to 1700 K. The data were analyzed using an ethane oxidation mechanism involving seven elementary reaction steps. Calculated growth constants were close to experimental values at lower temperatures, up to about 1400 K, but at higher temperatures computed growth constants were considerably smaller than experiment. In attempts to explain these results additional branching reactions were added to the mechanism. However, these additional reactions did not appreciably change calculated growth constants.

  2. Control of the anchoring behavior of polymer-dispersed liquid crystals: effect of branching in the side chains of polyacrylates.

    Science.gov (United States)

    Zhou, Jian; Collard, David M; Park, Jung O; Srinivasarao, Mohan

    2002-08-28

    A temperature-driven anchoring transition in a polymer/nematic fluid composite that is far from the bulk nematic-isotropic transition temperature is reported. A series of poly(methylheptyl acrylates) were studied to probe the subtle effects of the side chain structure of the polymer on control of the anchoring. A polymer-dispersed liquid crystal film made from TL205 and 1-methylheptyl acrylate shows only planar anchoring over the temperature range studied, while the films made from TL205 and each of the other methylheptyl acrylates or n-heptyl acrylate show the homeotropic-to-planar anchoring transition at temperatures between 70 and 78 degrees C. An interfacial model is proposed in which the different conformation of the side chains is suggested as the cause for the dramatic difference in the observed anchoring behavior. PMID:12188649

  3. Suppression of Aflatoxin Biosynthesis in Aspergillus flavus by 2-Phenylethanol Is Associated with Stimulated Growth and Decreased Degradation of Branched-Chain Amino Acids

    Directory of Open Access Journals (Sweden)

    Perng-Kuang Chang

    2015-09-01

    Full Text Available The saprophytic soil fungus Aspergillus flavus infects crops and produces aflatoxin. Pichia anomala, which is a biocontrol yeast and produces the major volatile 2-phenylethanol (2-PE, is able to reduce growth of A. flavus and aflatoxin production when applied onto pistachio trees. High levels of 2-PE are lethal to A. flavus and other fungi. However, at low levels, the underlying mechanism of 2-PE to inhibit aflatoxin production remains unclear. In this study, we characterized the temporal transcriptome response of A. flavus to 2-PE at a subinhibitory level (1 μL/mL using RNA-Seq technology and bioinformatics tools. The treatment during the entire 72 h experimental period resulted in 131 of the total A. flavus 13,485 genes to be significantly impacted, of which 82 genes exhibited decreased expression. They included those encoding conidiation proteins and involved in cyclopiazonic acid biosynthesis. All genes in the aflatoxin gene cluster were also significantly decreased during the first 48 h treatment. Gene Ontology (GO analyses showed that biological processes with GO terms related to catabolism of propionate and branched-chain amino acids (valine, leucine and isoleucine were significantly enriched in the down-regulated gene group, while those associated with ribosome biogenesis, translation, and biosynthesis of α-amino acids were over-represented among the up-regulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG pathway analysis revealed that metabolic pathways negatively impacted among the down-regulated genes parallel to those active at 30 °C, a condition conducive to aflatoxin biosynthesis. In contrast, metabolic pathways positively related to the up-regulated gene group resembled those at 37 °C, which favors rapid fungal growth and is inhibitory to aflatoxin biosynthesis. The results showed that 2-PE at a low level stimulated active growth of A. flavus but concomitantly rendered decreased activities in branched-chain amino

  4. Suppression of Aflatoxin Biosynthesis in Aspergillus flavus by 2-Phenylethanol Is Associated with Stimulated Growth and Decreased Degradation of Branched-Chain Amino Acids.

    Science.gov (United States)

    Chang, Perng-Kuang; Hua, Sui Sheng T; Sarreal, Siov Bouy L; Li, Robert W

    2015-10-01

    The saprophytic soil fungus Aspergillus flavus infects crops and produces aflatoxin. Pichia anomala, which is a biocontrol yeast and produces the major volatile 2-phenylethanol (2-PE), is able to reduce growth of A. flavus and aflatoxin production when applied onto pistachio trees. High levels of 2-PE are lethal to A. flavus and other fungi. However, at low levels, the underlying mechanism of 2-PE to inhibit aflatoxin production remains unclear. In this study, we characterized the temporal transcriptome response of A. flavus to 2-PE at a subinhibitory level (1 μL/mL) using RNA-Seq technology and bioinformatics tools. The treatment during the entire 72 h experimental period resulted in 131 of the total A. flavus 13,485 genes to be significantly impacted, of which 82 genes exhibited decreased expression. They included those encoding conidiation proteins and involved in cyclopiazonic acid biosynthesis. All genes in the aflatoxin gene cluster were also significantly decreased during the first 48 h treatment. Gene Ontology (GO) analyses showed that biological processes with GO terms related to catabolism of propionate and branched-chain amino acids (valine, leucine and isoleucine) were significantly enriched in the down-regulated gene group, while those associated with ribosome biogenesis, translation, and biosynthesis of α-amino acids OPEN ACCESS Toxins 2015, 7 3888 were over-represented among the up-regulated genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that metabolic pathways negatively impacted among the down-regulated genes parallel to those active at 30 °C, a condition conducive to aflatoxin biosynthesis. In contrast, metabolic pathways positively related to the up-regulated gene group resembled those at 37 °C, which favors rapid fungal growth and is inhibitory to aflatoxin biosynthesis. The results showed that 2-PE at a low level stimulated active growth of A. flavus but concomitantly rendered decreased activities in

  5. Isovaleryl-homoserine lactone, an unusual branched-chain quorum-sensing signal from the soybean symbiont Bradyrhizobium japonicum

    OpenAIRE

    Lindemann, Andrea; Pessi, Gabriella; Schaefer, Amy L.; Mattmann, Margrith E.; Christensen, Quin H.; Kessler, Aline; Hennecke, Hauke; Blackwell, Helen E.; Greenberg, E. Peter; Harwood, Caroline S.

    2011-01-01

    Many species of Proteobacteria communicate by using LuxI-LuxR–type quorum-sensing systems that produce and detect acyl-homoserine lactone (acyl-HSL) signals. Most of the known signals are straight-chain fatty acyl-HSLs, and evidence indicates that LuxI homologs prefer fatty acid-acyl carrier protein (ACP) over fatty acyl-CoA as the acyl substrate for signal synthesis. Two related LuxI homologs, RpaI and BtaI from Rhodopseudomonas palustris and photosynthetic stem-nodulating bradyrhizobia, dir...

  6. 随机环境中受控分枝过程的稳定性%STABILITY OF CONTROLLED BRANCHING CHAINS IN RANDOM ENVIRONMENT

    Institute of Scientific and Technical Information of China (English)

    王伟刚; 胡迪鹤

    2009-01-01

    本文研究了控制函数独立同分布,并且第n代的繁殖情况取决于环境的随机环境中分枝过程.给出了该模型稳定的充分条件,当环境平稳遍历时,得到了过程几乎处处灭绝的充分条件.%We consider controlled branching chains in random environments, that the controlled functions are i.i.d. random variables and the reproduction of an individual in the n-th season depends on the environments. Some results on process stability are shown. The extinction probabilities are given when environments are stationary and ergodic.

  7. Stabilization of bacterially expressed erythropoietin by single site-specific introduction of short branched PEG chains at naturally occurring glycosylation sites.

    Science.gov (United States)

    Hoffmann, E; Streichert, K; Nischan, N; Seitz, C; Brunner, T; Schwagerus, S; Hackenberger, C P R; Rubini, M

    2016-05-24

    The covalent attachment of polyethylene glycol (PEG) to therapeutic proteins can improve their physicochemical properties. In this work we utilized the non-natural amino acid p-azidophenylalanine (pAzF) in combination with the chemoselective Staudinger-phosphite reaction to install branched PEG chains to recombinant unglycosylated erythropoietin (EPO) at each single naturally occurring glycosylation site. PEGylation with two short 750 or 2000 Da PEG units at positions 24, 38, or 83 significantly decreased unspecific aggregation and proteolytic degradation while biological activity in vitro was preserved or even increased in comparison to full-glycosylated EPO. This site-specific bioconjugation approach permits to analyse the impact of PEGylation at single positions. These results represent an important step towards the engineering of site-specifically modified EPO variants from bacterial expression with increased therapeutic efficacy. PMID:26776361

  8. A small-angle X-ray scattering study of the effect of chain architecture on the shear-induced crystallization of branched and linear poly(ethylene terephthalate)

    OpenAIRE

    Hanley, T.; Sutton, D.; Heeley, E; Moad, G.; KNOTT, R.

    2007-01-01

    The synchrotron-based small-angle X-ray scattering (SAXS) technique was used to investigate the shear-induced crystallization kinetics of branched/unbranched poly(ethylene terephthalate) (PET). Reactive extrusion of bottle-grade PET with the branching and chain-extension agents pyromellitic dianhydride and pentaerythritol results in enhanced rheological properties, such as higher melt strength and higher viscosity. In this study, six samples of PET were investigated: linear PET [intrinsic vis...

  9. Chain extension and branching of poly(L-lactic acid produced by reaction with a DGEBA-based epoxy resin

    Directory of Open Access Journals (Sweden)

    2007-11-01

    Full Text Available Dicarboxylated poly(L-lactic acid (PLLA was synthesized by reacting succinic anhydride with L-lactic acid prepolymer prepared by melt polycondensation. PLLA and epoxy resin based on diglycidyl ether of bisphenol A (DGEBA copolymers were prepared by chain extension of dicarboxylated PLLA with DGEBA. Infrared spectra confirmed the formation of dicarboxylated PLLA and PLLA/DGEBA copolymer. Influences of reaction temperature, reaction time, and the amount of DGEBA on the molecular weight and gel content of PLLA/DGEBA copolymer were studied. The viscosity average molecular weight of PLLA/DGEBA copolymer reached 87 900 when reaction temperature, reaction time, and mol ratio of dicarboxylated PLLA to DGEBA is 150°C, 30 min, and 1:1 respectively, while gel content of PLLA/DGEBA copolymer is almost zero.

  10. Aspectos atuais sobre aminoácidos de cadeia ramificada e exercício físico Current aspects of branched chain amino acid and exercise

    Directory of Open Access Journals (Sweden)

    Marcelo Macedo Rogero

    2008-12-01

    Full Text Available Em humanos saudáveis, nove aminoácidos são considerados essenciais, uma vez que não podem ser sintetizados endogenamente e, portanto, devem ser ingeridos por meio da dieta. Dentre os aminoácidos essenciais, se incluem os três aminoácidos de cadeia ramificada, ou seja, leucina, valina e isoleucina. Esses aminoácidos participam da regulação do balanço protéico corporal além de serem fonte de nitrogênio para a síntese de alanina e glutamina. No tocante à regulação da síntese protéica muscular, verifica-se que a leucina age estimulando a fase de iniciação da tradução do RNA-mensageiro em proteína, por mecanismos tanto dependentes quanto independentes de insulina. No que concerne ao exercício físico, supõe-se que esses aminoácidos estejam envolvidos na fadiga central, no balanço protéico muscular, na secreção de insulina, na modulação da imunocompetência, no aumento da performance de indivíduos que se exercitam em ambientes quentes e na diminuição do grau de lesão muscular. Nesse contexto, essa revisão aborda os aspectos atuais do metabolismo e da suplementação de aminoácidos de cadeia ramificada no exercício físico.In healthy humans, nine amino acids are considered to be essential once they cannot be endogenously synthesised and must therefore be ingested in the diet. Amongst the essential amino acids are the three branched chain amino acids, namely, leucine, valine and isoleucine. These amino acids participate in the regulation of protein balance in addition to being nitrogen sources for the synthesis of alanine and glutamine. As to the regulation of muscle protein synthesis, leucine acts in the stimulation of initiation of mRNA translation into protein, both through mechanisms that are dependent and independent of insulin. In the physiology of physical exercise, these branched amino acids play a role in central fatigue hypothesis, in muscle protein balance, in the secretion of insulin, in the

  11. Comparison of the Photovoltaic Characteristics and Nanostructure of Fullerenes Blended with Conjugated Polymers with Siloxane-Terminated and Branched Aliphatic Side Chains

    KAUST Repository

    Kim, Do Hwan

    2013-02-12

    All-organic bulk heterojunction solar cells based on blends of conjugated polymers with fullerenes have recently surpassed the 8% efficiency mark and are well on their way to the industrially relevant ∼15% threshold. Using a low band-gap conjugated polymer, we have recently shown that polymer side chain engineering can lead to dramatic improvement in the in-plane charge carrier mobility. In this article, we investigate the effectiveness of siloxy side chain derivatization in controlling the photovoltaic performance of polymer:[6,6]-phenyl-C[71]-butyric acid methyl ester (PC71BM) blends and hence its influence on charge transport in the out-of-plane direction relevant for organic solar cells. We find that, in neat blends, the photocurrent of the polymer with siloxy side chains (PII2T-Si) is 4 times greater than that in blends using the polymer with branched aliphatic side chains (PII2T-ref). This difference is due to a larger out-of-plane hole mobility for PII2T-Si brought about by a largely face-on crystallite orientation as well as more optimal nanoscale polymer:PC71BM mixing. However, upon incorporating a common processing additive, 1,8-diiodooctane (DIO), into the spin-casting blend solution and following optimization, the PII2T-ref:PC71BM OPV device performance undergoes a large improvement and becomes the better-performing device, almost independent of DIO concentration (>1%). We find that the precise amount of DIO plays a larger role in determining the efficiency of PII2T-Si:PC71BM, and even at its maximum, the device performance lags behind optimized PII2T-ref:PC71BM blends. Using a combination of atomic force microscopy and small- and wide-angle X-ray scattering, we are able to elucidate the morphological modifications associated with the DIO-induced changes in both the nanoscale morphology and the molecular packing in blend films. © 2012 American Chemical Society.

  12. SYNTHESIS AND AGGREGATION BEHAVIOR OF 2-(4-BUTYLOCTYL) MALONIC-ACID IN AQUEOUS-SOLUTION - THE FORMATION OF PHYSICALLY AND COLLOIDALLY STABLE VESICLES BY A BRANCHED-CHAIN MALONATE

    NARCIS (Netherlands)

    de Groot, R.W.; Wagenaar, A.; Sein, A; Engberts, J.B.F.N.

    1995-01-01

    A new surfactant with a branched monoalkyl chain and a malonate headgroup has been synthesized: 2-(4-butyloctyl)malonic acid (BOMA). From the geometry of the surfactant, reflected in a packing parameter (P), it was anticipated that the surfactant would preferably aggregate in bilayers. This expectat

  13. Whey protein supplementation does not alter plasma branched-chained amino acid profiles but results in unique metabolomics patterns in obese women enrolled in an 8-week weight loss trial

    Science.gov (United States)

    Background: It has been suggested that perturbations in branched-chain amino acid (BCAA) catabolism are associated with insulin resistance and contribute to elevated systemic BCAAs. Evidence in rodents suggests dietary protein rich in BCAAs can increase BCAA catabolism, but there is limited evidence...

  14. Growth of the salt-tolerant yeast Zygosaccharomyces rouxii in microtiter plates : effects of NaCl, pH and temperature on growth and fusel alcohol production from branched-chain amino acids

    NARCIS (Netherlands)

    Jansen, Michael; Veurink, Janine H.; Euverink, Gert-Jan W.; Dijkhuizen, Lubbert

    2003-01-01

    Zygosaccharomyces rouxii, a salt-tolerant yeast isolated from the soy sauce process, produces fusel alcohols (isoamyl alcohol, active amyl alcohol and isobutyl alcohol) from branched-chain amino acids (leucine, isoleucine and valine, respectively) via the Ehrlich pathway. Using a high-throughput scr

  15. Evidence that the branched-chain amino acid L-valine prevents exercise-induced release of 5-HT in rat hippocampus.

    Science.gov (United States)

    Gomez-Merino, D; Béquet, F; Berthelot, M; Riverain, S; Chennaoui, M; Guezennec, C Y

    2001-07-01

    The branched-chain amino acid L-valine competes with tryptophan for transport into the brain and has previously been shown to decrease brain 5-HT synthesis. The purpose of this study was to assess, using a combined venous catheterization and in vivo microdialysis method, the effect of pre-exercise L-valine administration on 5-hydroxytryptamine (5-HT) metabolism in the ventral hippocampus of rats submitted to an acute intensive treadmill running (120 min at 25 m x min(-1) followed by 150 min of recovery). The presented results include measurement of extracellular tryptophan (TRP), the 5-HT precursor, and extracellular 5-hydroxyindoleacetic acid (5-HIAA), the 5-HT metabolite. The data clearly demonstrate that exercise induces 5-HT release in the rat hippocampus: in control group, hippocampal 5-HT levels increase from 123.7 +/- 6.4% at the end of exercise to 133.9 +/- 6.4% after 60 min of recovery. Moreover, two hours of intensive running induced significant increases both in extracellular TRP levels (from 120 min of exercise to 30 min of recovery) and 5-HIAA levels (from 90 min of exercise to 90 min of recovery). Pre-exercise administration of L-valine prevents significantly the exercise-induced 5-HT release: 5-HT levels are maintained to baseline during exercise and recovery. With regard to the competitive effect of L-valine with TRP, we could observe a treatment-induced decrease in brain TRP levels (from 120 min of exercise to the end of recovery). Besides, L-valine does not prevent exercise-induced increase in 5-HIAA levels. The present study evidences that an acute intensive exercise stimulates 5-HT metabolism in the rat hippocampus, and that a pre-exercise administration of L-valine prevents, via a limiting effect on 5-HT synthesis, exercise-induced 5-HT release. This study provides some anwers to previous human and animal investigations, showing physiological and psychological benefits of branched-chain amino acids supplementation on performance. PMID:11510866

  16. CypD(-/-) hearts have altered levels of proteins involved in Krebs cycle, branch chain amino acid degradation and pyruvate metabolism.

    Science.gov (United States)

    Menazza, Sara; Wong, Renee; Nguyen, Tiffany; Wang, Guanghui; Gucek, Marjan; Murphy, Elizabeth

    2013-03-01

    Cyclophilin D (CypD) is a mitochondrial chaperone that has been shown to regulate the mitochondrial permeability transition pore (MPTP). MPTP opening is a major determinant of mitochondrial dysfunction and cardiomyocyte death during ischemia/reperfusion (I/R) injury. Mice lacking CypD have been widely used to study regulation of the MPTP, and it has been shown recently that genetic depletion of CypD correlates with elevated levels of mitochondrial Ca(2+). The present study aimed to characterize the metabolic changes in CypD(-/-) hearts. Initially, we used a proteomics approach to examine protein changes in CypD(-/-) mice. Using pathway analysis, we found that CypD(-/-) hearts have alterations in branched chain amino acid metabolism, pyruvate metabolism and the Krebs cycle. We tested whether these metabolic changes were due to inhibition of electron transfer from these metabolic pathways into the electron transport chain. As we found decreased levels of succinate dehydrogenase and electron transfer flavoprotein in the proteomics analysis, we examined whether activities of these enzymes might be altered. However, we found no alterations in their activities. The proteomics study also showed a 23% decrease in carnitine-palmitoyltransferase 1 (CPT1), which prompted us to perform a metabolomics analysis. Consistent with the decrease in CPT1, we found a significant decrease in C4/Ci4, C5-OH/C3-DC, C12:1, C14:1, C16:1, and C20:3 acyl carnitines in hearts from CypD(-/-) mice. In summary, CypD(-/-) hearts exhibit changes in many metabolic pathways and caution should be used when interpreting results from these mice as due solely to inhibition of the MPTP.

  17. Mechanism of toxicity of the branched-chain fatty acid phytanic acid, a marker of Refsum disease, in astrocytes involves mitochondrial impairment.

    Science.gov (United States)

    Reiser, Georg; Schönfeld, Peter; Kahlert, Stefan

    2006-01-01

    Phytanic acid is a saturated branched-chain fatty acid, which is formed by bacterial degradation of chlorophyll in the intestinal tract of ruminants. The methyl group in beta-position prevents degradation of phytanic acid by the beta-oxidation pathway. Therefore, degradation of phytanic acid is initiated by alpha-oxidation in peroxisomes. The inherited peroxisomal disorder Refsum disease is characterised by accumulation of phytanic acid. Unusually high concentrations of phytanic acid can be found in the plasma of Refsum disease patients, who suffer from neurodegeneration and muscle dystrophy. Phytanic acid has been suggested to be causally involved in the clinical symptoms. To elucidate the pathogenic mechanism, we investigated the influence of phytanic acid in rat hippocampal astrocytes by monitoring the cytosolic Ca(2+) concentration, the mitochondrial membrane potential (Deltapsi(m)), the generation of reactive oxygen species as well as the cellular ATP level. In response to phytanic acid (100 microM) cytosolic Ca(2+) was quickly increased. The phytanic acid-evoked Ca(2+) response was transient and involved activation of intracellular Ca(2+) stores. In isolated rat brain mitochondria, phytanic acid dissipated Deltapsi(m) in a reversible and dose-dependent manner. Moreover, phytanic acid released cytochrome c from mitochondria. Depending on the mitochondrial activity state, phytanic acid either stimulated or inhibited the electron flux within the respiratory chain. In addition, phytanic acid induced substantial generation of reactive oxygen species in isolated mitochondria as well as in intact cells. Phytanic acid caused cell death of astrocytes within a few hours of exposure. In conclusion, we suggest that phytanic acid initiates astrocyte cell death by activating the mitochondrial route of apoptosis.

  18. Branched-chain amino acids ameliorate fibrosis and suppress tumor growth in a rat model of hepatocellular carcinoma with liver cirrhosis.

    Directory of Open Access Journals (Sweden)

    Jung Hoon Cha

    Full Text Available PURPOSE: Recent studies have revealed that branched-chain amino acids (BCAA reduce the development of hepatocellular carcinoma (HCC in patients with obesity and hepatitis C virus infection by improving insulin resistance (IR. The aim of this study was to examine the anti-cancer and anti-fibrotic effects of BCAA on the development of diethylnitrosamine (DEN-induced HCC and liver cirrhosis in a rat model. METHODS: Male SD rats received weekly intraperitoneal injections of DEN (50 mg/kg of body weight for 16 weeks to induce HCC. They were fed a diet containing 3% casein, 3% or 6% BCAA for 13 weeks beginning 6 weeks after DEN administration. DEN was used to induce HCC through stepwise development from cirrhosis to HCC. The effect of BCAA was evaluated in tumor tissues by histopathologic analyses, reverse transcription-polymerase chain reaction, and Western blotting. RESULTS: The mean area and number of dysplastic nodules (DNs and tumors in the casein group tended to be larger than those in the BCAA group 16 weeks after DEN administration. The mean fibrotic area in the BCAA group was smaller than that in the casein group. The BCAA group showed decreased mRNA levels for markers of fibrosis, angiogenesis, and apoptosis inhibition. Compared with the casein group, the BCAA group had lower levels of α-smooth muscle actin, vascular endothelial growth factor, p-β-catenin, p-p38 mitogen-activated protein kinase, proliferating cell nuclear antigen, and caspase-3 protein expression, as well as a higher level of cleaved caspase-3 protein expression. CONCLUSIONS: BCAA supplementation of the diet ameliorated liver fibrosis and HCC development in a DEN-induced rat model of HCC with liver cirrhosis, but not in the IR model. These results provide a rationale for anti-fibrosis and chemoprevention using BCAA treatment for HCC with liver cirrhosis, as well as decreasing the ammonia level.

  19. Expression, purification, crystallization and preliminary X-ray analysis of a novel N-substituted branched-chain l-amino-acid dioxygenase from Burkholderia ambifaria AMMD

    International Nuclear Information System (INIS)

    Diffraction data were collected to a limiting resolution of 2.4 Å from a crystal of selenomethionyl-labelled SadA, an l-amino-acid dioxygenase. Ferrous ion- and α-ketoglutarate-dependent dioxygenase from Burkholderia ambifaria AMMD (SadA) catalyzes the C3-hydroxylation of N-substituted branched-chain l-amino acids, especially N-succinyl-l-leucine, coupled to the conversion of α-ketoglutarate to succinate and CO2. SadA was expressed in Escherichia coli, purified and crystallized using the sitting-drop vapour-diffusion method at 293 K. Crystals of selenomethionine-substituted SadA were obtained using a reservoir solution containing PEG 3000 as the precipitant at pH 9.5 and diffracted X-rays to 2.4 Å resolution. The crystal belonged to space group P212121, with unit-cell parameters a = 49.3, b = 70.9, c = 148.2 Å. The calculated Matthews coefficient (VM = 2.1 Å3 Da−1, 41% solvent content) suggested that the crystal contains two molecules per asymmetric unit

  20. The Refsum disease marker phytanic acid, a branched chain fatty acid, affects Ca2+ homeostasis and mitochondria, and reduces cell viability in rat hippocampal astrocytes.

    Science.gov (United States)

    Kahlert, Stefan; Schönfeld, Peter; Reiser, Georg

    2005-02-01

    The saturated branched chain fatty acid, phytanic acid, a degradation product of chlorophyll, accumulates in Refsum disease, an inherited peroxisomal disorder with neurological clinical features. To elucidate the pathogenic mechanism, we investigated the influence of phytanic acid on cellular physiology of rat hippocampal astrocytes. Phytanic acid (100 microM) induced an immediate transient increase in cytosolic Ca2+ concentration, followed by a plateau. The peak of this biphasic Ca2+ response was largely independent of extracellular Ca2+, indicating activation of cellular Ca2+ stores by phytanic acid. Phytanic acid depolarized mitochondria without causing in situ swelling of mitochondria. The slow decrease of mitochondrial potential is not consistent with fast and simultaneous opening of the mitochondrial permeability transition pore. However, phytanic acid induced substantial generation of reactive oxygen species. Phytanic acid caused astroglia cell death after a few hours of exposure. We suggest that the cytotoxic effect of phytanic acid seems to be due to a combined action on Ca2+ regulation, mitochondrial depolarization, and increased ROS generation in brain cells.

  1. High Leucine Diets Stimulate Cerebral Branched-Chain Amino Acid Degradation and Modify Serotonin and Ketone Body Concentrations in a Pig Model.

    Science.gov (United States)

    Wessels, Anna G; Kluge, Holger; Hirche, Frank; Kiowski, Andreas; Schutkowski, Alexandra; Corrent, Etienne; Bartelt, Jörg; König, Bettina; Stangl, Gabriele I

    2016-01-01

    In addition to its role as an essential protein component, leucine (Leu) displays several other metabolic functions such as activation of protein synthesis. This property makes it an interesting amino acid for the therapy of human muscle atrophy and for livestock production. However, Leu can stimulate its own degradation via the branched-chain keto acid dehydrogenase complex (BCKDH). To examine the response of several tissues to excessive Leu, pigs were fed diets containing two- (L2) and four-fold (L4) higher Leu contents than the recommended amount (control). We found that the L4 diet led to a pronounced increase in BCKDH activity in the brain (2.5-fold, P pancreas, skeletal muscle, adipose tissue and intestinal mucosa. The L2 diet had only weak effects on BCKDH activity. Both high Leu diets reduced the concentrations of free valine and isoleucine in nearly all tissues. In the brain, high Leu diets modified the amount of tryptophan available: for serotonin synthesis. Compared to the controls, pigs treated with the high Leu diets consumed less food, showed increased plasma concentrations of 3-hydroxybutyrate and reduced levels of circulating serotonin. In conclusion, excessive Leu can stimulate BCKDH activity in several tissues, including the brain. Changes in cerebral tryptophan, along with the changes in amino acid-derived metabolites in the plasma may limit the use of high Leu diets to treat muscle atrophy or to increase muscle growth. PMID:26930301

  2. Effects of diets supplemented with branched-chain amino acids on the performance and fatigue mechanisms of rats submitted to prolonged physical exercise.

    Science.gov (United States)

    Falavigna, Gina; Alves de Araújo, Jonas; Rogero, Marcelo Macedo; Pires, Ivanir Santana de Oliveira; Pedrosa, Rogério Graça; Martins, Eivor; Alves de Castro, Inar; Tirapegui, Julio

    2012-11-01

    This study aimed to determine the effects of diets chronically supplemented with branched-chain amino acids (BCAA) on the fatigue mechanisms of trained rats. Thirty-six adult Wistar rats were trained for six weeks. The training protocol consisted of bouts of swimming exercise (one hour a day, five times a week, for six weeks). The animals received a control diet (C) (n = 12), a diet supplemented with 3.57% BCAA (S1) (n = 12), or a diet supplemented with 4.76% BCAA (S2) (n = 12). On the last day of the training protocol, half the animals in each group were sacrificed after one hour of swimming (1H), and the other half after a swimming exhaustion test (EX). Swimming time until exhaustion was increased by 37% in group S1 and reduced by 43% in group S2 compared to group C. Results indicate that the S1 diet had a beneficial effect on performance by sparing glycogen in the soleus muscle (p rats subjected to a swimming test to exhaustion. However, this is a dose-dependent effect, since chronic ingestion of elevated quantities of BCAA led to a reduction in performance. PMID:23201847

  3. Different Lipopolysaccharide Branched-Chain Amino Acids Modulate Porcine Intestinal Endogenous β-Defensin Expression through the Sirt1/ERK/90RSK Pathway.

    Science.gov (United States)

    Ren, Man; Zhang, Shihai; Liu, Xutong; Li, Shenghe; Mao, Xiangbing; Zeng, Xiangfang; Qiao, Shiyan

    2016-05-01

    Nutritional induction of endogenous antimicrobial peptide expression is considered a promising approach to inhibit the outgrowth and infection of pathogenic microbes in mammals. The present study investigated possible regulation of porcine epithelial β-defensins in response to branched-chain amino acids (BCAA) in vivo and in vitro. BCAA treatment increased relative mRNA expression of jejunal and ileal β-defensins in weaned piglets. In IPEC-J2 cells, isoleucine, leucine, and valine could stimulate β-defensin expression, possibly associated with stimulation of ERK1/2 phosphorylation. Inhibition of Sirt1 and ERK completely blocked the activation of ERK and 90RSK protein by isoleucine, simultaneously decreasing defensin expression. BCAA stimulate expression of porcine intestinal epithelial β-defensins with isoleucine the most, potent possibly through activation of the Sirt1/ERK/90RSK signaling pathway. The β-defensins regulation of lipopolysaccharide was related with an ERK-independent pathway. BCAA modulation of endogenous defensin might be a promising approach to enhance disease resistance and intestinal health in young animals and children. PMID:27083206

  4. High-Speed Microdialysis-Capillary Electrophoresis Assays for Measuring Branched Chain Amino Acid Uptake in 3T3-L1 cells.

    Science.gov (United States)

    Harstad, Rachel K; Bowser, Michael T

    2016-08-16

    We have developed a high-throughput microdialysis-capillary electrophoresis (MD-CE) assay for monitoring branched chain amino acid (BCAA) uptake/release dynamics in 3T3-L1 cells. BCAAs (i.e., isoleucine, leucine, and valine) and their downstream metabolites (i.e., alanine, glutamine, and glutamate) are important indicators of adipocyte lipogenesis. To perform an analysis, amino acids were sampled using microdialysis, fluorescently labeled in an online reaction, separated using CE, and detected using laser-induced fluorescence (LIF) in a sheath flow cuvette. Separation conditions were optimized for the resolution of the BCAAs isoleucine, leucine, and valine, as well as 13 other amino acids, including ornithine, alanine, glutamine, and glutamate. CE separations were performed in <30 s, and the temporal resolution of the online MD-CE assay was <60 s. Limits of detection (LOD) were 400, 200, and 100 nM for isoleucine, leucine, and valine, respectively. MD-CE dramatically improved throughput in comparison to traditional offline CE methods, allowing 8 replicates of 15 samples (i.e., 120 analyses) to be assayed in <120 min. The MD-CE assay was used to assess the metabolism dynamics of 3T3-L1 cells over time, confirming the utility of the assay. PMID:27398773

  5. Branched-Chain Amino Acid Supplementation in Combination with Voluntary Running Improves Body Composition in Female C57BL/6 Mice.

    Science.gov (United States)

    Platt, Kristen M; Charnigo, Richard J; Shertzer, Howard G; Pearson, Kevin J

    2016-01-01

    Exercise is an inexpensive intervention that may be used to reduce obesity and its consequences. In addition, many individuals who regularly exercise utilize dietary supplements to enhance their exercise routine and to accelerate fat loss or increase lean mass. Branched-chain amino acids (BCAAs) are a popular supplement and have been shown to produce a number of beneficial effects in rodent models and humans. Therefore, we hypothesized that BCAA supplementation would protect against high fat diet (HFD)-induced glucose intolerance and obesity in mice with and without access to exercise. We subjected 80 female C57BL/6 mice to a paradigm of HFD feeding, exercise in the form of voluntary wheel running, and BCAA supplementation in the drinking water for 16 weeks (n = 10 per group). Body weight was monitored weekly, while food and water consumption were recorded twice weekly. During the 5th, 10th, and 15th weeks of treatment, glucose tolerance and body composition were analyzed. Exercise significantly improved glucose tolerance in both control-fed and HFD-fed mice. BCAA supplementation, however, did not significantly alter glucose tolerance in any treatment group. While BCAA supplements did not improve lean to fat mass ratio in sedentary mice, it significantly augmented the effects of exercise on this parameter. PMID:26716948

  6. Efficient synthesis of D-branched-chain amino acids and their labeled compounds with stable isotopes using D-amino acid dehydrogenase.

    Science.gov (United States)

    Akita, Hironaga; Suzuki, Hirokazu; Doi, Katsumi; Ohshima, Toshihisa

    2014-02-01

    D-Branched-chain amino acids (D-BCAAs) such as D-leucine, D-isoleucine, and D-valine are known to be peptide antibiotic intermediates and to exhibit a variety of bioactivities. Consequently, much effort is going into achieving simple stereospecific synthesis of D-BCAAs, especially analogs labeled with stable isotopes. Up to now, however, no effective method has been reported. Here, we report the establishment of an efficient system for enantioselective synthesis of D-BCAAs and production of D-BCAAs labeled with stable isotopes. This system is based on two thermostable enzymes: D-amino acid dehydrogenase, catalyzing NADPH-dependent enantioselective amination of 2-oxo acids to produce the corresponding D-amino acids, and glucose dehydrogenase, catalyzing NADPH regeneration from NADP(+) and D-glucose. After incubation with the enzymes for 2 h at 65°C and pH 10.5, 2-oxo-4-methylvaleric acid was converted to D-leucine with an excellent yield (>99 %) and optical purity (>99 %). Using this system, we produced five different D-BCAAs labeled with stable isotopes: D-[1-(13)C,(15)N]leucine, D-[1-(13)C]leucine, D-[(15)N]leucine, D-[(15)N]isoleucine, and D-[(15)N]valine. The structure of each labeled D-amino acid was confirmed using time-of-flight mass spectrometry and nuclear magnetic resonance analysis. These analyses confirmed that the developed system was highly useful for production of D-BCAAs labeled with stable isotopes, making this the first reported enzymatic production of D-BCAAs labeled with stable isotopes. Our findings facilitate tracer studies investigating D-BCAAs and their derivatives. PMID:23661083

  7. Exercise-induced muscle damage is reduced in resistance-trained males by branched chain amino acids: a randomized, double-blind, placebo controlled study

    Directory of Open Access Journals (Sweden)

    Howatson Glyn

    2012-07-01

    Full Text Available Abstract Background It is well documented that exercise-induced muscle damage (EIMD decreases muscle function and causes soreness and discomfort. Branched-chain amino acid (BCAA supplementation has been shown to increase protein synthesis and decrease muscle protein breakdown, however, the effects of BCAAs on recovery from damaging resistance training are unclear. Therefore, the aim of this study was to examine the effects of a BCAA supplementation on markers of muscle damage elicited via a sport specific bout of damaging exercise in trained volunteers. Methods Twelve males (mean ± SD age, 23 ± 2 y; stature, 178.3 ± 3.6 cm and body mass, 79.6 ± 8.4 kg were randomly assigned to a supplement (n = 6 or placebo (n = 6 group. The damaging exercise consisted of 100 consecutive drop-jumps. Creatine kinase (CK, maximal voluntary contraction (MVC, muscle soreness (DOMS, vertical jump (VJ, thigh circumference (TC and calf circumference (CC were measured as markers of muscle damage. All variables were measured immediately before the damaging exercise and at 24, 48, 72 and 96 h post-exercise. Results A significant time effect was seen for all variables. There were significant group effects showing a reduction in CK efflux and muscle soreness in the BCAA group compared to the placebo (P Conclusion The present study has shown that BCAA administered before and following damaging resistance exercise reduces indices of muscle damage and accelerates recovery in resistance-trained males. It seems likely that BCAA provided greater bioavailablity of substrate to improve protein synthesis and thereby the extent of secondary muscle damage associated with strenuous resistance exercise. Clinical Trial Registration Number: NCT01529281.

  8. Content and Composition of Branched-Chain Fatty Acids in Bovine Milk Are Affected by Lactation Stage and Breed of Dairy Cow.

    Directory of Open Access Journals (Sweden)

    Melissa L Bainbridge

    Full Text Available Dairy products contain bioactive fatty acids (FA and are a unique dietary source of an emerging class of bioactive FA, branched-chain fatty acids (BCFA. The objective of this study was to compare the content and profile of bioactive FA in milk, with emphasis on BCFA, among Holstein (HO, Jersey (JE, and first generation HO x JE crossbreeds (CB across a lactation to better understand the impact of these factors on FA of interest to human health. Twenty-two primiparous cows (n = 7 HO, n = 7 CB, n = 8 JE were followed across a lactation. All cows were fed a consistent total mixed ration (TMR at a 70:30 forage to concentrate ratio. Time points were defined as 5 days in milk (DIM, 95 DIM, 185 DIM, and 275 DIM. HO and CB had a higher content of n-3 FA at 5 DIM than JE and a lower n-6:n-3 ratio. Time point had an effect on the n-6:n-3 ratio, with the lowest value observed at 5 DIM and the highest at 185 DIM. The content of vaccenic acid was highest at 5 DIM, yet rumenic acid was unaffected by time point or breed. Total odd and BCFA (OBCFA were higher in JE than HO and CB at 185 and 275 DIM. Breed affected the content of individual BCFA. The content of iso-14:0 and iso-16:0 in milk was higher in JE than HO and CB from 95 to 275 DIM. Total OBCFA were affected by time point, with the highest content in milk at 275 DIM. In conclusion, HO and CB exhibited a higher content of several bioactive FA in milk than JE. Across a lactation the greatest content of bioactive FA in milk occurred at 5 DIM and OBCFA were highest at 275 DIM.

  9. Content and Composition of Branched-Chain Fatty Acids in Bovine Milk Are Affected by Lactation Stage and Breed of Dairy Cow.

    Science.gov (United States)

    Bainbridge, Melissa L; Cersosimo, Laura M; Wright, André-Denis G; Kraft, Jana

    2016-01-01

    Dairy products contain bioactive fatty acids (FA) and are a unique dietary source of an emerging class of bioactive FA, branched-chain fatty acids (BCFA). The objective of this study was to compare the content and profile of bioactive FA in milk, with emphasis on BCFA, among Holstein (HO), Jersey (JE), and first generation HO x JE crossbreeds (CB) across a lactation to better understand the impact of these factors on FA of interest to human health. Twenty-two primiparous cows (n = 7 HO, n = 7 CB, n = 8 JE) were followed across a lactation. All cows were fed a consistent total mixed ration (TMR) at a 70:30 forage to concentrate ratio. Time points were defined as 5 days in milk (DIM), 95 DIM, 185 DIM, and 275 DIM. HO and CB had a higher content of n-3 FA at 5 DIM than JE and a lower n-6:n-3 ratio. Time point had an effect on the n-6:n-3 ratio, with the lowest value observed at 5 DIM and the highest at 185 DIM. The content of vaccenic acid was highest at 5 DIM, yet rumenic acid was unaffected by time point or breed. Total odd and BCFA (OBCFA) were higher in JE than HO and CB at 185 and 275 DIM. Breed affected the content of individual BCFA. The content of iso-14:0 and iso-16:0 in milk was higher in JE than HO and CB from 95 to 275 DIM. Total OBCFA were affected by time point, with the highest content in milk at 275 DIM. In conclusion, HO and CB exhibited a higher content of several bioactive FA in milk than JE. Across a lactation the greatest content of bioactive FA in milk occurred at 5 DIM and OBCFA were highest at 275 DIM. PMID:26930646

  10. Effects of Diets Supplemented with Branched-Chain Amino Acids on the Performance and Fatigue Mechanisms of Rats Submitted to Prolonged Physical Exercise

    Directory of Open Access Journals (Sweden)

    Inar Alves de Castro

    2012-11-01

    Full Text Available This study aimed to determine the effects of diets chronically supplemented with branched-chain amino acids (BCAA on the fatigue mechanisms of trained rats. Thirty-six adult Wistar rats were trained for six weeks. The training protocol consisted of bouts of swimming exercise (one hour a day, five times a week, for six weeks. The animals received a control diet (C (n = 12, a diet supplemented with 3.57% BCAA (S1 (n = 12, or a diet supplemented with 4.76% BCAA (S2 (n = 12. On the last day of the training protocol, half the animals in each group were sacrificed after one hour of swimming (1H, and the other half after a swimming exhaustion test (EX. Swimming time until exhaustion was increased by 37% in group S1 and reduced by 43% in group S2 compared to group C. Results indicate that the S1 diet had a beneficial effect on performance by sparing glycogen in the soleus muscle (p < 0.05 and by inducing a lower concentration of plasma ammonia, whereas the S2 diet had a negative effect on performance due to hyperammonemia (p < 0.05. The hypothalamic concentration of serotonin was not significantly different between the 1H and EX conditions. In conclusion, chronic BCAA supplementation led to increased performance in rats subjected to a swimming test to exhaustion. However, this is a dose-dependent effect, since chronic ingestion of elevated quantities of BCAA led to a reduction in performance.

  11. Effect of chronic supplementation with branched-chain amino acids on the performance and hepatic and muscle glycogen content in trained rats.

    Science.gov (United States)

    de Araujo, Jonas A; Falavigna, Gina; Rogero, Marcelo M; Pires, Ivanir S O; Pedrosa, Rogerio G; Castro, Inar A; Donato, Jose; Tirapegui, Julio

    2006-08-29

    The objective of this study was to evaluate the effects of a diet supplemented with branched-chain amino acids (BCAA; 3.57% and 4.76%) on the performance and glycogen metabolism of trained rats. Thirty-six adult male Wistar rats received the control diet (AIN-93M) (n=12) and two diets supplemented with BCAA (S1: AIN-93M+3.57% BCAA, n=12, and S2: AIN-93M+4.76% BCAA, n=12) for 6 weeks. The training protocol consisted of bouts of swimming exercise (60 min day(-1)) for 6 weeks at intensities close to the lactate threshold. On the last day of the experiment, all groups were trained for 1 h (1H) or were submitted to the exhaustion test (EX). The time to exhaustion did not differ between groups. The groups submitted to the exhaustion test presented a reduction in plasma glucose and an increase in plasma ammonia and blood lactate concentrations compared to the 1H condition. In the 1H condition, hepatic glycogen concentration was significantly higher in group S2 compared to the control diet and S1 groups (132% and 44%, respectively). Group S2 in the 1H condition presented a higher muscle glycogen concentration (45%) compared to the control diet group. In the EX condition, a significantly higher hepatic glycogen concentration was observed for group S2 compared to the control diet and S1 groups (262% and 222%, respectively). Chronic supplementation with BCAA promoted a higher hepatic and muscle glycogen concentration in trained animals, with this effect being dose dependent. PMID:16698042

  12. Intake of branched-chain or essential amino acids attenuates the elevation in muscle levels of PGC-1α4 mRNA caused by resistance exercise.

    Science.gov (United States)

    Samuelsson, Hedvig; Moberg, Marcus; Apró, William; Ekblom, Björn; Blomstrand, Eva

    2016-07-01

    The transcriptional coactivator peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α is recognized as the master regulator of mitochondrial biogenesis. However, recently a novel isoform, PGC-1α4, that specifically regulates muscle hypertrophy was discovered. Because stimulation of mechanistic target of rapamycin complex 1 (mTORC1) activity is tightly coupled to hypertrophy, we hypothesized that activation of this pathway would upregulate PGC-1α4. Eight male subjects performed heavy resistance exercise (10 × 8-12 repetitions at ∼75% of 1 repetition maximum in leg press) on four different occasions, ingesting in random order a solution containing essential amino acids (EAA), branched-chain amino acids (BCAA), leucine, or flavored water (placebo) during and after the exercise. Biopsies were taken from the vastus lateralis muscle before and immediately after exercise, as well as following 90 and 180 min of recovery. Signaling through mTORC1, as reflected in p70S6 kinase phosphorylation, was stimulated to a greater extent by the EAA and BCAA than the leucine or placebo supplements. Unexpectedly, intake of EAA or BCAA attenuated the stimulatory effect of exercise on PGC-1α4 expression by ∼50% (from a 10- to 5-fold increase with BCAA and EAA, P Muscle glycogen levels were reduced and AMP-activated protein kinase α2 activity and phosphorylation of p38 mitogen-activated protein kinase enhanced to the same extent with all four supplements. In conclusion, induction of PGC-1α4 does not appear to regulate the nutritional (BCAA or EAA)-mediated activation of mTORC1 in human muscle. PMID:27245337

  13. Analysis of the LIV System of Campylobacter jejuni Reveals Alternative Roles for LivJ and LivK in Commensalism beyond Branched-Chain Amino Acid Transport ▿

    OpenAIRE

    Ribardo, Deborah A.; Hendrixson, David R.

    2011-01-01

    Campylobacter jejuni is a leading cause of diarrheal disease in humans and an intestinal commensal in poultry and other agriculturally important animals. These zoonotic infections result in significant amounts of C. jejuni present in the food supply to contribute to disease in humans. We previously found that a transposon insertion in Cjj81176_1038, encoding a homolog of the Escherichia coli LivJ periplasmic binding protein of the leucine, isoleucine, and valine (LIV) branched-chain amino aci...

  14. Effects of supplementation with branched-chain amino acids to low-protein diets on expression of genes related to lipid metabolism in skeletal muscle of growing pigs.

    Science.gov (United States)

    Duan, Yehui; Duan, Yangmiao; Li, Fengna; Li, Yinghui; Guo, Qiuping; Ji, Yujiao; Tan, Bie; Li, Tiejun; Yin, Yulong

    2016-09-01

    Branched-chain amino acids (BCAA), including leucine (Leu), isoleucine (Ile), and valine (Val), play critical roles in energy homeostasis and lipid metabolism in addition to their other functions, such as in protein metabolism. This study investigated the effects of different dietary BCAA ratios on the intramuscular fat (IMF) content and fatty acid composition in different location of skeletal muscles, including the longissimus dorsi (LD), biceps femoris (BF), and psoas major (PM) muscles of growing pigs, and also examined the mRNA expression levels of genes involved in lipid metabolism in these muscle tissues. The experiment was performed on 40 growing pigs (Large White × Landrace) with a similar initial weight (9.85 ± 0.35 kg). The pigs were randomly assigned to one of five diets: diet A was a positive control and contained 20 % crude protein (CP) with a Leu:Ile:Val ratio of 1:0.51:0.63 according to the recommendation of the National Research Council (NRC); for diets B to E, the CP level was reduced to 17 %, and the Leu:Ile:Val ratios were 1:1:1, 1:0.75:0.75, 1:0.51:0.63, and 1:0.25:0.25, respectively. No significant difference was observed in the average feed intake and feed efficiency of the pigs fed the low protein diet (17 % CP) with BCAA treatments relative to the positive control. However, there was a tendency for increased feed efficiency of the 1:0.75:0.75 group compared with the 1:1:1 group (P = 0.09). The BCAA ratio of 1:0.75:0.75 (17 % CP) increased the IMF content of BF muscle (P protein level had different effects on the fatty acid composition of the LD, BF, and PM muscles. The BCAA ratio of 1:0.51:0.63-1:0.75:0.75 (17 % CP) significantly lowered the ratio of n-6 to n-3 polyunsaturated fatty acid in these muscles compared with the positive control group (20 % CP). This effect was associated with an increase in mRNA expression levels of acetyl-CoA carboxylase, lipoprotein lipase, fatty acid transport protein, and fatty acid binding

  15. Total branched-chain amino acids requirement in patients with maple syrup urine disease by use of indicator amino acid oxidation with L-[1-13C]phenylalanine.

    Science.gov (United States)

    Riazi, Roya; Rafii, Mahroukh; Clarke, Joe T R; Wykes, Linda J; Ball, Ronald O; Pencharz, Paul B

    2004-07-01

    Maple syrup urine disease (MSUD) is an autosomal recessive disorder caused by defects in the mitochondrial multienzyme complex branched-chain alpha-keto acid dehydrogenase (BCKD; EC 1.2.4.4), responsible for the oxidative decarboxylation of the branched-chain ketoacids (BCKA) derived from the branched-chain amino acids (BCAA) leucine, valine, and isoleucine. Deficiency of the enzyme results in increased concentrations of the BCAA and BCKA in body cells and fluids. The treatment of the disease is aimed at keeping the concentration of BCAA below the toxic concentrations, primarily by dietary restriction of BCAA intake. The objective of this study was to determine the total BCAA requirements of patients with classical MSUD caused by marked deficiency of BCKD by use of the indicator amino acid oxidation (IAAO) technique. Five MSUD patients from the MSUD clinic of The Hospital for Sick Children participated in the study. Each was randomly assigned to different intakes of BCAA mixture (0, 20, 30, 50, 60, 70, 90, 110, and 130 mg.kg(-1).day(-1)), in which the relative proportion of BCAA was the same as that in egg protein. Total BCAA requirement was determined by measuring the oxidation of l-[1-(13)C]phenylalanine to (13)CO(2). The mean total BCAA requirement was estimated using a two-phase linear regression crossover analysis, which showed that the mean total BCAA requirement was 45 mg.kg(-1).day(-1), with the safe level of intake (upper 95% confidence interval) at 62 mg.kg(-1).day(-1). This is the first time BCAA requirements in patients with MSUD have been determined directly.

  16. Structure of pestalotan, a highly branched (1----3)-beta-D-glucan elaborated by Pestalotia sp. 815, and the enhancement of its antitumor activity by polyol modification of the side chains.

    Science.gov (United States)

    Misaki, A; Kawaguchi, K; Miyaji, H; Nagae, H; Hokkoku, S; Kakuta, M; Sasaki, T

    1984-07-01

    Pestalotia sp. 815, a newly isolated fungus, produces extracellularly a highly (1----6)-branched (1----3)-beta-D-glucan in high yield when grown in a D-glucose-containing medium. This extracellular glucan, designated "Pestalotan", has [alpha]25D-0.1 degree (c 0.5, M NaOH) and a molecular weight greater than 2 X 10(6). Chemical and enzymic studies indicated that pestalotan has a very highly branched structure containing a back-bone chain of beta-D-(1----3)-linked D-glucosyl residues, and three out of five D-glucosyl residues are substituted at O-6, mostly with single D-glucosyl groups, and a very few with short beta-(1----6)-linked oligosaccharide units. This D-glucan becomes water-insoluble after isolation from the culture filtrate followed by dehydration, and shows moderate growth-inhibitory activities against mouse-implanted tumors. However, when the D-glucosyl groups of the side chains were modified by periodate oxidation and borohydride reduction, the resulting, still water-insoluble, D-glucan polyol exhibited potent antitumor activities, confirming that the attachment of many polyhydroxy groups to the beta-D-(1----3)-linked D-glucan back-bone gives a remarkable enhancement effect on the antitumor activity of the branched D-glucan. Prolonged treatment of the D-glucan polyol by ultrasonic irradiation afforded a low-molecular-weight D-glucan polyol (SD-pestalotan polyol), without alteration of its chemical structure. The water-soluble, SD-pestalotan polyol, having a molecular weight of 4.7 X 10(5), exhibited remarkable antitumor activities against both allogeneic and syngeneic, mouse-implanted tumors, at small dosages (1-5 mg/kg for 10 days) by intraperitoneal administration. A comparison of values of the molecular weight of SD-pestalotan polyol, estimated by 3-MPa l.c. for the aqueous solution and the dimethyl sulfoxide solution, strongly suggested that the D-glucan polyol must form a triple-chain conformation in aqueous solution. PMID:6547877

  17. Linear, branched and network polysilanes with thienyl/furyl substituted sila-alkyl side chains and their applications for the synthesis of fluorescent silver nanoparticles/clusters

    Indian Academy of Sciences (India)

    Ravi Shankar; Usharani Sahoo; Vandana Shahi; Manchal Chaudhary

    2012-11-01

    The scope of Wurtz coupling and catalytic dehydrocoupling methods for the synthesis of functional polysilanes of compositions, [RR'Si] (linear), [(PhMeSi)-co-(RSi)1−] (branched) and [RSi] (network) [R = Et3SiCH2CH2, 2-Fu/2-ThMe2SiCH2CH2 (Fu = Furyl, Th = Thienyl), -Hex or Ph; R' = H or Me] is presented. By virtue of -delocalized silicon backbone and variable HOMO-LUMO band gap energies, these polymers are found to be promising candidates as reducing agents for Ag(I) ions in toluene/cyclo-hexane and provide a simple approach for ‘size-controlled’ synthesis of silver nanoparticles (AgNPs) as well as fluorescent polymer-silver nanocomposites.

  18. Branching out

    CERN Document Server

    Biggins, J D

    2010-01-01

    Results on the behaviour of the rightmost particle in the $n$th generation in the branching random walk are reviewed and the phenomenon of anomalous spreading speeds, noticed recently in related deterministic models, is considered. The relationship between such results and certain coupled reaction-diffusion equations is indicated.

  19. Protein Characterization of Na+-Independent System L Amino Acid Transporter 3 in Mice : A Potential Role in Supply of Branched-Chain Amino Acids under Nutrient Starvation

    OpenAIRE

    Fukuhara, Daisuke; Kanai, Yoshikatsu; Chairoungdua, Arthit; Babu, Ellappan; Bessho, Fumio; Kawano, Toshio; Akimoto, Yoshihiro; Endou, Hitoshi; Yan, Kunimasa

    2007-01-01

    We recently cloned the human Na+-independent system L neutral amino acid transporter LAT3. The aim of the present study was to characterize the molecular nature of mouse LAT3 at the protein level. Isolated mouse LAT3 showed 83% identity to human LAT3. Xenopus oocytes injected with mouse LAT3 cRNA showed the same functional property as human LAT3. Reverse transcriptase-polymerase chain reaction revealed apparent transcripts of mouse LAT3 in the liver, skeletal muscle, and pancreas, an expressi...

  20. The influence of the branched-chain fatty acids pristanic acid and Refsum disease-associated phytanic acid on mitochondrial functions and calcium regulation of hippocampal neurons, astrocytes, and oligodendrocytes.

    Science.gov (United States)

    Rönicke, Sabine; Kruska, Nicol; Kahlert, Stefan; Reiser, Georg

    2009-11-01

    Pristanic acid and phytanic acid are branched-chain fatty acids, which play an important role in diseases with peroxisomal impairment, like Refsum disease (MIM 266500), Zellwegers syndrome and alpha-methylacyl-CoA racemase deficiency (MIM 604489). Several studies revealed that the toxic activity of phytanic acid is mediated by multiple mitochondrial dysfunctions. However, the action of pristanic acid on brain cells is still completely unknown. Here, we exposed astrocytes, oligodendrocytes and neurons in mixed culture to pristanic acid and phytanic acid to analyse cellular consequences. Pristanic acid exerts a strong cytotoxic activity on brain cells, displayed by dramatic Ca2+ deregulation, in situ mitochondrial depolarization and cell death. Interestingly, pristanic acid strongly induced generation of reactive oxygen species (ROS), whereas phytanic acid exerts weaker effects on ROS production. In conclusion, pristanic acid as well as phytanic acid induced a complex array of toxic activities with mitochondrial dysfunction and Ca2+ deregulation.

  1. Multiple shape-memory behavior and thermal-mechanical properties of peroxide cross-linked blends of linear and short-chain branched polyethylenes

    Directory of Open Access Journals (Sweden)

    2008-07-01

    Full Text Available Thermally induced shape-memory effect (SME in tensile mode was investigated in binary and ternary blends of two ethylene-1-octene copolymers with a degree of branching of 30 and 60 CH3/1000C and/or nearly linear polyethylene cross-linked after melt mixing with 2 wt% of liquid peroxide 2,5-dimethyl-2,5-di-(tert.butylperoxy-hexane at 190°C. The average cross-link density estimated by means of the Mooney-Rivlin equation on the basis of tensile test data was characterized between 130 and 170 mol•m–3 depending on the blend composition. Thermal analysis points out multiple crystallization and melting behavior of blends caused by the existence of several polyethylene crystal populations with different perfection, size and correspondingly different melting temperature of crystallites. That agrees well with the diversity of blends phase morphology characterized by atomic force microscopy. However, triple- and quadruple-SME could be observed only after two- and accordingly three-step programming of binary and tertiary blends, respectively, at suitable temperatures and strains. Compared to performances obtained for the same blend after single-step programming above the maximal melting temperature the significantly poorer characteristics of SME like strain fixity and strain recovery ratio as well as recovery strain rate occurred after multi-step programming.

  2. Mechanical properties of branched actin filaments

    CERN Document Server

    Razbin, Mohammadhosein; Benetatos, Panayotis; Zippelius, Annette

    2015-01-01

    Cells moving on a two dimensional substrate generate motion by polymerizing actin filament networks inside a flat membrane protrusion. New filaments are generated by branching off existing ones, giving rise to branched network structures. We investigate the force-extension relation of branched filaments, grafted on an elastic structure at one end and pushing with the free ends against the leading edge cell membrane. Single filaments are modeled as worm-like chains, whose thermal bending fluctuations are restricted by the leading edge cell membrane, resulting in an effective force. Branching can increase the stiffness considerably; however the effect depends on branch point position and filament orientation, being most pronounced for intermediate tilt angles and intermediate branch point positions. We describe filament networks without cross-linkers to focus on the effect of branching. We use randomly positioned branch points, as generated in the process of treadmilling, and orientation distributions as measur...

  3. Solubility of n-butane and 2-methylpropane (isobutane) in 1-alkyl-3-methylimidazolium-based ionic liquids with linear and branched alkyl side-chains.

    Science.gov (United States)

    Pison, Laure; Shimizu, Karina; Tamas, George; Lopes, José Nuno Canongia; Quitevis, Edward L; Gomes, Margarida F Costa

    2015-11-11

    The solubility of n-butane and 2-methylpropane (isobutane) in three ionic liquids - 1-(2-methylpropyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [(2mC3)C1im][Ntf2], 1-(3-methylbutyl)-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [(3mC4)C1im][Ntf2] and 1-methyl-3-pentylimidazolium bis(trifluoromethylsulfonyl)imide [C5C1im][Ntf2] - has been measured at atmospheric pressure from 303 to 343 K. Isobutane is less soluble than n-butane in all the ionic liquids. Henry's constant values range from 13.8 × 10(5) Pa for n-butane in [C5C1im][Ntf2] at 303 K to 64.5 × 10(5) Pa for isobutane in [(2mC3)C1im][Ntf2] at 343 K. The difference in solubility between the two gases can be explained by a more negative enthalpy of solvation for n-butane. A structural analysis of the pure solvents and of the solutions of the gases, probed by molecular dynamics simulations, could explain the differences found in the systems: (i) the nonpolar domains of the ionic liquids accommodate better the long and more flexible n-butane solute; (ii) the small differences in solubility of each gas in the ionic liquids with the same number of carbon atoms in the alkyl side-chains are explained by the absence of large structural differences in the pure solvents. In all cases, the structural analysis of the four ionic liquids confirms that the studied gases can act as probes of the molecular structure of the ionic liquids, the simulations being always compatible with the experimental solubility data.

  4. Research Progress in Synthesis of the Branched-chain of Antibacterial Agent Gemifloxacin%抗菌剂吉米沙星支链的合成研究进展

    Institute of Scientific and Technical Information of China (English)

    刘巧云; 陈文华

    2011-01-01

    吉米沙星是一种新型喹诺酮类抗菌剂,其支链是影响其药效的最重要部分,对药理活性有决定性影响。文章综述了吉米沙星支链的合成方法,并对各种方法进行比较分析,总结出各自的优缺点。采用氧化剂法合成吉米沙星支链,反应条件温和,总收率最高可达39.6%,三废污染少。此工艺中的中间体3(4-氰基-1-(N-叔丁氧羰基)吡咯烷-3-酮)还原成中间体4’(4-氨甲基-1-(N-叔丁氧羰基)吡咯烷-3-醇)时,宜采用硼氢化物-氯化盐为还原剂;中间体5,(4-(N-叔丁氧羰基)氨甲基-1-(N-叔丁氧羰基)吡咯烷-3-醇)氧化成中间体6(4-(N-叔丁氧羰基)氨甲基-1-(N-叔丁氧羰基)吡咯烷-3-酮)时,宜采用Jones试剂为氧化剂,收率及纯度高,易于操作。%Gemifloxacin is one of the new quinolone antibacterial agents. The branched-chain of it is the most important part of the efficacy, which has the decisive influence to the pharmacology activity. Synthetic methods of the branched-chain have been reviewed, these methods have been analyzed and compared with each other, and the merits and defects of each method have been presented. It's better to use oxidation methods to synthesize the branched-chain then non- oxidation methods with milder conditions, low in the pollution of the environment and an overall yield of 39.6%. In the methods, it is suitable to use borohydride-chlorizated salts when intermediate 3 (4-cyano- 1-(N-t-butoxycarbony)pyrrolidin-3-keton) is reduced to 4 (4-aminomethyl- 1-(N-t-butoxycarbony)pyrrolidin-3-alcohol ) and to use Jones reagent when intermediate 5' (4-(N-t-butoxycarbony)aminomethyl- 1-(N-t-butoxycarbony)pyrrolidin-3-alcohol) is oxidezed to 6 (4-(N-t-butoxycarbony)aminomethyl- 1-(N-t-butoxycarbony)pyrrolidin-3-keton) with high yield, good purity and easy operation.

  5. 缝合神经的指固有动脉背支血管链皮瓣修复指远端皮肤缺损%Repair of fingertip defect with proper digital artery lateral cutaneous branch-chain flap accompanied with dorsal digital nerve or dorsal branch of proper digital nerve coaptation

    Institute of Scientific and Technical Information of China (English)

    孙涛; 魏鹏; 周丹亚; 胡瑞斌; 滕晓峰; 陈宏

    2011-01-01

    Objective To explore the effect of using proper digital artery lateral cutaneous branch-chain flap with dorsal digital nerves or dorsal branch of proper digital nerye for repairing of fingertip defect.Methods From December 2008 to November 2009, 24 cases (26 digits) of fingertip defect were treated with proper digital artery lateral cutaneous branch-chain flap.The flap was designed on the lateral side of the proximal phalanx of the injured finger with its long axis running on the lateral midline of the finger.The vascular pedicle was 0.8 to 1.0 cm wide.The pivot point was at the distal 1/3 of the middle phalanx upon which the flap was reversed to repair the defect of the fingertip.The dorsal digital nerve or dorsal branch of proper digital nerve was included in the flap and coapted with the nerve in the wound to reconstruct sensation of the injured finger.Results All 26 flaps survived.Postoperative follow-up period was 6 to 8 months.All these flaps recovered with satisfying and quality, excellent sensation with 4 to 8 mm two-point discrimination.ROM of the interphalangeal joint of the injured finger was good.Conclusion Proper digital artery lateral cutaneous branchchain flap transfer with nerve coaptation is an ideal method for repairing fingertip defect.The surgery is simple.Reliable blood supply can be achieved without sacrificing the proper digital artery.Coaptation of the nerve restores sensation at the fingertip.There is minor donor site damage and very few complications.%目的 探讨缝合神经的指固有动脉背支血管链皮瓣修复指远端皮肤缺损的疗效.方法 2008年12月至2009年11月,对24例26指指远端皮肤缺损患者,以指固有动脉背侧支形成的血管链为血供,于近节指体侧方设计皮瓣,皮瓣轴线为指体侧方中线,皮瓣蒂宽0.8~1.0cm,皮瓣转折点为中节指体中远端,逆行转移修复指远端皮肤缺损,皮瓣携带指固有神经背侧支或指背神经与创面指神经断端进行缝合

  6. Synthesis, characterization and lubricating effect of long chain branched polydimethylsiloxane-g-polyethylene copolymers%长支链型PDMS-g-PE共聚物的制备及其增塑润滑作用

    Institute of Scientific and Technical Information of China (English)

    金震; 范宏

    2016-01-01

    Long chain branched polydimethylsiloxane-g-polyethylene (PDMS-g-PE) copolymers were synthesized by hydrosilylation reaction between polymethylhydrosiloxane and vinyl terminated PE macromonomer. The structure and properties were characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance spectroscopy (1H NMR), high temperature gel permeation chromatography (HT-GPC) and differential scanning calorimetry (DSC). The effect of the hydrogen content of polymethylhydrosiloxane on the copolymer structure and properties was investigated. It was found that the molecular weight of PDMS-g-PE increased with the hydrogen content of polymethylhydrosiloxane since more PE macromonomers were grafted onto the polydimethylsiloxane main chains. The glass transition temperature (Tg) of PDMS-g-PE was extremely low, indicating the excellent molecular chain flexibility. PDMS-g-PE with more PE branched chains showed higher melting temperature (Tm) and higher melting enthalpy (ΔHm). PDMS-g-PE was used as flow modifier for HDPE. When 2% PDMS-g-PE was added to HDPE, the melting flow rate (MFR) increased by 21%, the elongation at break improved significantly and the impact strength improved a little, while the tensile strength and elastic modulus decreased slightly.%通过低含氢硅油与末端双键聚乙烯大单体的硅氢加成反应,制备了长支链型聚硅氧烷-聚乙烯接枝共聚物(PDMS-g-PE)。采用傅里叶变换红外光谱(FT-IR)、核磁共振波谱(1H NMR)、高温凝胶渗透色谱(HT-GPC)和差示扫描量热分析(DSC)表征了共聚物的结构与性能。考察了硅油含氢量对共聚物结构和热性能的影响,并将其用作HDPE的流动改性剂,研究了其增塑润滑改性效果。结果表明,硅油含氢量越高,能加成上的PE支链越多,PDMS-g-PE的分子量越大。PDMS-g-PE的聚硅氧烷主链具有极低的玻璃化温度(Tg),显示出优异的分子链柔顺性。聚

  7. Phytanic acid and pristanic acid, branched-chain fatty acids associated with Refsum disease and other inherited peroxisomal disorders, mediate intracellular Ca2+ signaling through activation of free fatty acid receptor GPR40.

    Science.gov (United States)

    Kruska, Nicol; Reiser, Georg

    2011-08-01

    The accumulation of the two branched-chain fatty acids phytanic acid and pristanic acid is known to play an important role in several diseases with peroxisomal impairment, like Refsum disease, Zellweger syndrome and α-methylacyl-CoA racemase deficiency. Recent studies elucidated that the toxic activity of phytanic acid and pristanic acid is mediated by multiple mitochondrial dysfunctions, generation of reactive oxygen species and Ca2+ deregulation via the InsP3-Ca2+ signaling pathway in glial cells. However, the exact signaling mechanism through which both fatty acids mediate toxicity is still under debate. Here, we studied the ability of phytanic acid and pristanic acid to activate the free fatty acid receptor GPR40, a G-protein-coupled receptor, which was described to be involved in the Ca2+ signaling of fatty acids. We treated HEK 293 cells expressing the GPR40 receptor with phytanic acid or pristanic acid. This resulted in a significant increase in the intracellular Ca2+ level, similar to the effect seen after treatment with the synthetic GPR40 agonist GW9508. Furthermore, we demonstrate that the GPR40 activation might be due to an interaction of the carboxylate moiety of fatty acids with the receptor. Our findings indicate that the phytanic acid- and pristanic acid-mediated Ca2+ deregulation can involve the activation of GPR40. Therefore, we suppose that activation of GPR40 might be part of the signaling cascade of the toxicity of phytanic and pristanic acids.

  8. Branched-Chain Amino Acids as Pharmacological Nutrients in Chronic Liver Disease%支链氨基酸作为药理营养素在慢性肝病治疗中的应用

    Institute of Scientific and Technical Information of China (English)

    王芃; 谢青

    2011-01-01

    Branched-chain amino acids (BCAAs) are a group of essential amino acids including valine, leucine and isoleucine. A low ratio of plasma BCAAs to aromatic amino acids is a physiological hallmark of liver cirrhosis. Recent studies on BCAAs have revealed that, in addition to their role as protein constituents, they may have a role as pharmacological nutrients for patients with chronic liver disease. This review summarizes the possible effects of BCAAs on albumin synthesis and insulin resistance from clinical and basic viewpoints. Meanwhile, the newly discovered clinical impact of BCAAs on the prognosis and quality of life of patients with hepatocellular carcinoma and liver cirrhosis are reviewed.%支链氨基酸是一组包括缬氨酸、亮氨酸和异亮氨酸等的人体必需氨基酸.支链氨基酸除了其蛋白质成分的作用,可能对慢性肝病患者具有药理营养素作用.本文从基础研究和临床角度对支链氨基酸在合成白蛋白和胰岛素抵抗作用上可能产生的影响,以及对肝癌和肝硬化患者的生活质量和预后的临床作用作一综述.

  9. Insights into the Mechanism of Homeoviscous Adaptation to Low Temperature in Branched-Chain Fatty Acid-Containing Bacteria through Modeling FabH Kinetics from the Foodborne Pathogen Listeria monocytogenes.

    Science.gov (United States)

    Saunders, Lauren P; Sen, Suranjana; Wilkinson, Brian J; Gatto, Craig

    2016-01-01

    The psychrotolerant foodborne pathogen Listeria monocytogenes withstands the stress of low temperatures and can proliferate in refrigerated food. Bacteria adapt to growth at low temperatures by increasing the production of fatty acids that increase membrane fluidity. The mechanism of homeoviscous increases in unsaturated fatty acid amounts in bacteria that predominantly contain straight-chain fatty acids is relatively well understood. By contrast the analogous mechanism in branched-chain fatty acid-containing bacteria, such as L. monocytogenes, is poorly understood. L. monocytogenes grows at low temperatures by altering its membrane composition to increase membrane fluidity, primarily by decreasing the length of fatty acid chains and increasing the anteiso to iso fatty acid ratio. FabH, the initiator of fatty acid biosynthesis, has been identified as the primary determinant of membrane fatty acid composition, but the extent of this effect has not been quantified. In this study, previously determined FabH steady-state parameters and substrate concentrations were used to calculate expected fatty acid compositions at 30°C and 10°C. FabH substrates 2-methylbutyryl-CoA, isobutyryl-CoA, and isovaleryl-CoA produce the primary fatty acids in L. monocytogenes, i.e., anteiso-odd, iso-even, and iso-odd fatty acids, respectively. In vivo concentrations of CoA derivatives were measured, but not all were resolved completely. In this case, estimates were calculated from overall fatty acid composition and FabH steady-state parameters. These relative substrate concentrations were used to calculate the expected fatty acid compositions at 10°C. Our model predicted a higher level of anteiso lipids at 10°C than was observed, indicative of an additional step beyond FabH influencing fatty acid composition at low temperatures. The potential for control of low temperature growth by feeding compounds that result in the production of butyryl-CoA, the precursor of SCFAs that rigidify the

  10. 补充支链氨基酸对运动能力影响的研究进展%Research Development on Branched-Chain Amino Acid Supplement And Exercise Capacity

    Institute of Scientific and Technical Information of China (English)

    唐芳; 张蕴琨

    2012-01-01

    As necessary amino acids,Branched-chain amino acid(BCAA)is closely related to our exercise abilities.on the one hand,BCAA supplement can reduce protein catabolism,and promote gluconeogenesis,Therefore,the strength and anaerobic exercise capacity were improved.On the one hand,The ability of BCAA oxidation and decomposition in vivo to produce ATP is more efficiently than other amino acids.Branched-chain amino acid supplement can reduce the / ratio,and decrease the formation of 5-HT to provide energy reserving endurance exercise.However,some academics also suggested that the BCAA has no effect on exercise capacity and even have a negative impact,mainly because a large number of BCAA supplement may lead to blood ammonia elevated,thereby affecting exercise capacity,Therefore,scholars focus on the dose of BCAA during BCAA supplement.However,because of the complexity of the exercise test,the dose of BCAA supplement,the concentration of BCAA and the ratio of leucine,isoleucine and valine(Val) have no determine,how to supply BCAA reasonablly need further research Meanwhile,the mechanism of BCAA involved in glucose metabolism is not clear.In addition,during a long time,the effects of BCAA supplement on exercise capacity is still no conclusive.Following with application of micro-dialysis and other new technology,these problems will be solved.%支链氨基酸(BCAA)作为人体必需氨基酸,与人体的运动能力密切相关。一方面,补充BCAA能减少蛋白质的分解代谢,并促进糖异生,可以提高力量和无氧运动能力。另一方面,支链氨基酸在体内氧化分解产生ATP的效率高于其他氨基酸,补充BCAA可以降低[游离色氨酸(f-Trp)]/[BCAA]的比值,减少5-羟色胺(5-HT)形成,为机体长时间耐力运动提供能量。但是学术界也有人认为支链氨基酸对运动能力没有影响甚至会产生负面影响,主要原因是大量补充支链氨基酸会引起血氨升高,进而影响运动能力,故

  11. A Rapid and Sensitive UPLC-MS/MS-Method for the Separation and Quantification of Branched-Chain Amino Acids from Dried Blood Samples of Patients with Maple Syrup Urine Disease (MSUD

    Directory of Open Access Journals (Sweden)

    Ralph Fingerhut

    2016-06-01

    Full Text Available Newborn screening for MSUD is a special challenge since patients with MSUD can metabolically decompensate rapidly without adequate treatment within the first two weeks of life. However, the screening method does not detect the actual marker metabolite (alloisoleucine specifically, but only as part of the group of the other isobaric amino acids leucine, isoleucine and hydroxyproline. We describe a sensitive and rapid second-tier UPLC-MS/MS method to determine branched-chain amino acids from the initial extraction of the screening sample. Quantification is based on a seven-point calibration curve. Reference ranges (mean ± SD in µmol/L were determined from 179 normal, not pre-selected samples from the newborn screening: leucine: 72 ± 27; isoleucine: 37 ± 19; valine: 98 ± 46; hydroxyproline: 23 ± 13. The concentration of alloisoleucine was below the detection limit in about 55% of the cases, and the highest concentration was 1.9 µmol/L. In all 30 retrospectively studied screening samples from patients with confirmed MSUD the concentration of alloisoleucine was significantly increased. In 238 samples with false-positive newborn screening due to a significant increase in the combined concentration of leucine + isoleucine + alloisoleucine + hydroxyproline (400 to >4000 µmol/L, alloisoleucine was below 6.5 µmol/L (n = 57 or not detectable (n = 181. The application of this assay markedly reduces the false-positive rate and the associated anxiety and costs. It is also suitable for routinely monitoring blood spots of patients with MSUD.

  12. 基于图像处理的分支链氨基酸菌体形状识别%Bacterium Body Shape Recognition of Branched Chain Amino Acid Based on Image Processing

    Institute of Scientific and Technical Information of China (English)

    李达; 丁莉莎; 马雷; 王以忠; 陈宁

    2012-01-01

      提出了一种用于分支链氨基酸发酵过程中菌体形状识别的方法。该方法基于菌体的图像,充分利用菌体的形状特征,将菌体图像的面积作为第一步识别特征,然后将菌体中心的位置作为第二步识别特征,最后对菌体图像进行编码作为第三步识别特征。实验表明,该方法可以对分支链氨基酸发酵过程中的菌体形状进行准确快速的识别。%  A method of recognizing body shapes of bacteria during fermentation process of branched chain amino acid (BCAA) was proposed, which is based on the images of bacteria. In order to ful y make use of shape properties of bacteria, the areas of bacteria were used for the first-step recognition. Then, the positions of the centers of bacterium images were used for the second-step recognition. Final y, the images of bacteria were coded for the third-step recognition. Recognition experiments were conducted with satisfied results to show the proposed method recognizes the shapes of bacteria during fermentation process of BCAA correctly and fast.

  13. Supplementation of branched-chain amino acids to a reduced-protein diet improves growth performance in piglets: involvement of increased feed intake and direct muscle growth-promoting effect.

    Science.gov (United States)

    Zheng, Liufeng; Wei, Hongkui; Cheng, Chuanshang; Xiang, Quanhang; Pang, Jiaman; Peng, Jian

    2016-06-01

    The aim of this study was to investigate whether supplementing branched-chain amino acids (AA) (BCAA) along with a reduced-protein diet increases piglet growth, and whether elevated feed intake and muscle growth-promoting effect contribute to this improvement. In Expt 1, twenty-eight weanling piglets were randomly fed one of the following four diets: a positive control (PC) diet, a reduced-protein negative control (NC) diet, an NC diet supplemented with BCAA to the same levels as in the PC diet (test 1 (T1)) and an NC diet supplemented with a 2-fold dose of BCAA in T1 diet (test 2 (T2)) for 28 d. In Expt 2, twenty-one weanling piglets were randomly assigned to NC, T1 and pair-fed T1 (P) groups. NC and T1 diets were the same as in Expt 1, whereas piglets in the P group were individually pair-fed with the NC group. In Expt 1, the NC group had reduced piglet growth and feed intake compared with the PC group, which were restored in T1 and T2 groups, but no differences were detected between T1 and T2 groups. In Expt 2, T1 and P groups showed increases in growth and mass of some muscles compared with the NC group. Increased feed intake after BCAA supplementation was associated with increased mRNA expressions of agouti-related peptide and co-express neuropeptide Y (NPY) and phosphorylation of mammalian target of rapamycin (mTOR) and ribosomal protein S6 kinase 1 (S6K1), as well as decreased mRNA expressions of melanocortin-4 receptor and cocaine- and amphetamine-regulated transcript and phosphorylation of eukaryotic initiation factor 2α in the hypothalamus. No differences were observed among PC, T1 and T2 groups except for higher NPY mRNA expression in the T2 group than in the PC group (Expt 1). Phosphorylation of mTOR and S6K1 in muscle was enhanced after BCAA supplementation, which was independent of change in feed intake (Expt 2). In conclusion, supplementing BCAA to reduced-protein diets increases feed intake and muscle mass, and contributes to better growth

  14. Study on Rheological Property and Foam Morphology of Linear and Long Chain Branching PP/NaCl Blends%线性和长支链聚丙烯/氯化钠共混物的流变性能及发泡形态的研究

    Institute of Scientific and Technical Information of China (English)

    黄锦涛; 何光建; 廖霞; 张海琛

    2012-01-01

    Linear and long chain branching PP/NaCl composites were prepared. The rheological behav-ior , thermal properties and foam morphology of them were studied by rheological test, DSC and supercritical carbon dioxide foaming technology. Rheological test confirmed that under UV irradiation branching was a-chieved, and the long-chain branching structure was not changed by adding NaCl. The more NaCl added, the smaller the extensional viscosity. The results of DSC revealed that with the introducing of long chain branching, the melting range of the PP broadened and the crystallization temperature increased. Adding NaCl could make the crystallization temperature decreasing, and little change in melting point. The foam morpholo-gies of long chain branching polypropylene were more uniform. Open-pore Foams can be obtained by porogen, the more content of porogen, the higher degree of open-pore was.%制备了线性和长支链聚丙烯/氯化钠(NaCl)共混物,通过流变仪、差示扫描量热仪(DSC)及超临界二氧化碳发泡方法研究了共混物的流变性能、热性能及发泡形态.流变结果表明,紫外辐照挤出改性后的聚丙烯(PP)样品都接入了长支链,NaCl的加入没有改变长支链结构,且NaCl加入得越多,拉伸黏度越小.通过DSC可知,随着长支链的引入,聚丙烯的熔程变宽,结晶温度有所提升,而NaCl的加入使得结晶温度下降,熔点变化不大.通过紫外辐照反应挤出改性引入长支链可有效改善PP的发泡形态.加入致孔剂可制得开孔材料,开孔程度随着致孔剂的含量的增大而增大.

  15. Branched polynomial covering maps

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    2002-01-01

    A Weierstrass polynomial with multiple roots in certain points leads to a branched covering map. With this as the guiding example, we formally define and study the notion of a branched polynomial covering map. We shall prove that many finite covering maps are polynomial outside a discrete branch...... set. Particular studies are made of branched polynomial covering maps arising from Riemann surfaces and from knots in the 3-sphere. (C) 2001 Elsevier Science B.V. All rights reserved....

  16. Quantification of branching in model three-arm star polyethylene

    KAUST Repository

    Ramachandran, Ramnath

    2012-01-24

    The versatility of a novel scaling approach in quantifying the structure of model well-defined 3-arm star polyethylene molecules is presented. Many commercial polyethylenes have long side branches, and the nature and quantity of these branches varies widely among the various forms. For instance, low-density polyethylene (LDPE) is typically a highly branched structure with broad distributions in branch content, branch lengths and branch generation (in hyperbranched structures). This makes it difficult to accurately quantify the structure and the inherent structure-property relationships. To overcome this drawback, model well-defined hydrogenated polybutadiene (HPB) structures have been synthesized via anionic polymerization and hydrogenation to serve as model analogues to long-chain branched polyethylene. In this article, model 3-arm star polyethylene molecules are quantified using the scaling approach. Along with the long-chain branch content in polyethylene, the approach also provides unique measurements of long-chain branch length and hyperbranch content. Such detailed description facilitates better understanding of the effect of branching on the physical properties of polyethylene. © 2012 American Chemical Society.

  17. Processability improvement of polyolefins through radiation-induced branching

    Science.gov (United States)

    Cheng, Song; Phillips, Ed; Parks, Lewis

    2010-03-01

    Radiation-induced long-chain branching for the purpose of improving melt strength and hence the processability of polypropylene (PP) and polyethylene (PE) is reviewed. Long-chain branching without significant gel content can be created by low dose irradiation of PP or PE under different atmospheres, with or without multifunctional branching promoters. The creation of long-chain branching generally leads to improvement of melt strength, which in turn may be translated into processability improvement for specific applications in which melt strength plays an important role. In this paper, the changes of the melt flow rate and the melt strength of the irradiated polymer and the relationship between long-chain branching and melt strength are reviewed. The effects of the atmosphere and the branching promoter on long-chain branching vs. degradation are discussed. The benefits of improved melt strength on the processability, e.g., sag resistance and strain hardening, are illustrated. The implications on practical polymer processing applications such as foams and films are also discussed.

  18. Melons are branched polymers

    CERN Document Server

    Gurau, Razvan

    2013-01-01

    Melonic graphs constitute the family of graphs arising at leading order in the 1/N expansion of tensor models. They were shown to lead to a continuum phase, reminiscent of branched polymers. We show here that they are in fact precisely branched polymers, that is, they possess Hausdorff dimension 2 and spectral dimension 4/3.

  19. ANALYSIS OF BRANCHING DISTRIBUTION IN POLYETHYLENES BY DIFFERENTIAL SCANNING CALORIMETRY

    Institute of Scientific and Technical Information of China (English)

    Robert Shanks; Fei Chen; Gandara Amarasinghe

    2003-01-01

    Short chain branching has been characterized using thermal fractionation, a stepwise isothermal crystallization technique, followed by a melting analysis scan using differential scanning calorimetry. Short chain branching distribution was also characterized by a continuous slow cooling crystallization, followed by a melting analysis scan. Four different polyethylenes were studied: Ziegler-Natta gas phase, Ziegler-Natta solution, metallocene, constrained-geometry single site catalyzed polyethylenes. The branching distribution was calculated from a calibration of branch content with melting temperature. The lamellar thickness was calculated based on the thermodynamic melting temperature of each polyethylene and the surface free energy of the crystal face. The branching distribution and lamellar thickness distribution were used to calculate weight average branch content, mean lamellar thickness, and a branch dispersity index. The results for the branch content were in good agreement with the known comonomer content of the polyethylenes. A limitation was that high branch content polyethylenes did not reach their potential crystallization at ambient temperatures. Cooling to sub-ambient was necessary to equilibrate the crystallization, but melting temperature versus branch content was not applicable after cooling to below ambient because the calibration data were not performed in this way.

  20. Structural analysis of the sialylated N- and O-linked carbohydrate chains of recombinant human erythropoietin expressed in Chinese hamster ovary cells. Sialylation patterns and branch location of dimeric N-acetyllactosamine units

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Hokke, C.H.; Bergwerff, A.A.; Dedem, G.W.K. van; Kamerling, J.P.

    1995-01-01

    The N-linked carbohydrate chains of recombinant human erythropoietin expressed in CHO cells were quantitatively released with peptide-N4-(N-acetyl-beta-glucosaminyl)asparagine amidase F, separated from the remaining O-glycoprotein by gel-permeation chromatography, and subsequently fractionated via F

  1. Materials Test Branch

    Science.gov (United States)

    Gordon, Gail

    2012-01-01

    The Materials Test Branch resides at Marshall Space Flight Center's Materials and Processing laboratory and has a long history of supporting NASA programs from Mercury to the recently retired Space Shuttle. The Materials Test Branch supports its customers by supplying materials testing expertise in a wide range of applications. The Materials Test Branch is divided into three Teams, The Chemistry Team, The Tribology Team and the Mechanical Test Team. Our mission and goal is to provide world-class engineering excellence in materials testing with a special emphasis on customer service.

  2. Branching processes in biology

    CERN Document Server

    Kimmel, Marek

    2015-01-01

    This book provides a theoretical background of branching processes and discusses their biological applications. Branching processes are a well-developed and powerful set of tools in the field of applied probability. The range of applications considered includes molecular biology, cellular biology, human evolution and medicine. The branching processes discussed include Galton-Watson, Markov, Bellman-Harris, Multitype, and General Processes. As an aid to understanding specific examples, two introductory chapters, and two glossaries are included that provide background material in mathematics and in biology. The book will be of interest to scientists who work in quantitative modeling of biological systems, particularly probabilists, mathematical biologists, biostatisticians, cell biologists, molecular biologists, and bioinformaticians. The authors are a mathematician and cell biologist who have collaborated for more than a decade in the field of branching processes in biology for this new edition. This second ex...

  3. Koenigs function and branching processes

    CERN Document Server

    Chikilev, O G

    2001-01-01

    An explicit solution of time-homogeneous pure birth branching processes is described. It gives alternative extensions for the negative binomial distribution (branching processes with immigration) and for the Furry-Yule distribution (branching processes without immigration).

  4. 指固有动脉皮支血管链逆行侧方皮瓣修复手指软组织缺损%Flap Pedicled with Lateral Vascular Chain of Cutaneous Branch of Digital Artery to Repair the Soft Tissue Defect of the Distal Finger

    Institute of Scientific and Technical Information of China (English)

    李超; 王浩; 潘朝晖

    2014-01-01

    目的:探讨指固有动脉皮支血管链逆行侧方皮瓣修复手指远端软组织缺损的效果。方法以指固有动脉背侧皮支上行支、下行支形成的链式吻合供血,在手指近节侧方切取皮瓣。皮瓣的轴线是手指侧方中线,皮瓣旋转点为中节指体中远端,皮瓣的蒂部宽度为0.5~1.0cm。皮瓣携带指背神经与创面指神经断端进行缝合修复,重建手指感觉。逆行移位皮瓣修复指端创面32例。结果32例皮瓣全部成活。术后随访6个月~1年,皮瓣外形与正常相近,弹性、色泽良好。缺损饱满而不臃肿,质地柔软,有排汗功能,两点辨别觉达5~9 mm。结论采用指固有动脉皮支血管链逆行侧方皮瓣一期修复指端缺损,疗程短,效果好,操作简单,血供可靠,不牺牲指固有动脉、神经,供区损伤小,术后并发症少,并且能重建皮瓣感觉,是一种理想的手术修复方法。%Objective To explore the effect of flap pedicled with lateral vascular chain of cutaneous branch of digital artery to re -pair the soft tissue defect of the distal finger .Methods The flap based on the dorsal cutaneous branch of digital artery ,the ascending branch and the descending branch formation of supply vascular chain in the finger's lateral.The axis of the flap was finger lateral midline , the rotation point of flap was the middle finger of the distal , and the pedicle width of flap was 0.5~1.0cm.Flap repaird dorsal nerve and stump nerve , reconstructed of the finger's feeling.Retrograde transposition of flap in 32 cases to repair finger end .Results All flaps survived in 32 cases. After followed up for 6 months~1 years,flap had the normal close,elastic,good colour.Defect was full and not bloated , and soft texture,had the function that discharge sweat ,two-point discrimination Jueda 5~9mm.Conclusion Flap pedicled with lateral vascular chain of cutane-ous branch of digital artery to repair the

  5. 链转移剂单体存在下自由基NaSCN溶液聚合制备支化聚丙烯腈%Preparation of Branched Polyacrylonitrile via Free Radical Polymerization in NaSCN Solution with a Chain Transfer Monomer

    Institute of Scientific and Technical Information of China (English)

    张岩; 崔逸; 黄文艳; 薛小强; 杨宏军; 蒋必彪

    2014-01-01

    Branched polyacrylonitrile (BPAN) was prepared by traditional radical polymerization in the presence of 2-(3-mercaptopropionyloxy)ethyl methacrylate (MMPOE) as the chain transfer monomer. Vinyl acetate (VAc) was introduced as the second monomer, and the polymerization was initiated using 2,2'-azobisisobutyronitrile (AIBN) and carried out in 45% NaSCN solution. The influence of chain transfer monomer dosage on the copolymerization was investigated. Gas chromatography (GC), proton nuclear magnetic resonance (1H-NMR), triple-detection gel-permeation chromatography (TD-GPC), and rotation rheometer were used to determine the monomer conversion, molecular weight and viscosity of the resulted branched polymer. The results show that, PAN with high degree of branching was prepared and the degree of branching increases when the dosage of MMPOE increases, while the molecular weight decreases gradually with the increase of MMPOE dosage because of chain transfer reaction. The zero-shear viscosity of branched PAN solution with 15.7%solid content is only 12.7%of their linear counterpart with the same molecular weight at 25℃.%以偶氮二异丁腈(AIBN)为引发剂,醋酸乙烯酯(VAc)为第二单体,甲基丙烯酸-3-巯基丙酰氧基乙酯(MMPOE)为链转移剂单体,45%硫氰酸钠(NaSCN)水溶液为溶剂,进行常规自由基共聚反应合成支化聚丙烯腈(BPAN);研究了链转移剂单体含量对聚合物的影响。通过气相色谱(GC)、核磁共振氢谱(1H-NMR)、三检测凝胶渗透色谱(TD-GPC)、旋转流变仪分别对聚合反应过程和聚合产物进行了表征分析。结果表明:在NaSCN水溶液体系中,以MMPOE为链转移剂单体制得了较高支化程度的支化PAN,其支化程度随MMPOE含量的增加而提高,分子量随MMPOE含量的增加而降低;25℃下,15.7%固体含量的支化PAN溶液的零剪切黏度(η0=3.52 Pa·s)仅为其同分子量的线型聚合物溶液黏度(η0=27.7 Pa·s)的12.7%。

  6. Synthesis of branched polysaccharides with tunable degree of branching

    NARCIS (Netherlands)

    Ciric, Jelena; Loos, Katja

    2013-01-01

    An in vitro enzyme-catalyzed tandem reaction using the enzymes phosphorylase b from rabbit muscle and Deinococcus geothermalis glycogen branching enzyme (Dg GBE) to obtain branched polyglucans with tunable degree of branching (2% divided by 13%) is presented. The tunable degree of branching is obtai

  7. Choice of Bond Dissociation Enthalpies on which to Base the Stabilization Energies of Simple Radicals: DH(R-H)is Preferred because DH(R-Me) is Perturbed by Changes in Chain Branching

    Energy Technology Data Exchange (ETDEWEB)

    Poutsma, Marvin L [ORNL

    2008-01-01

    The relative stabilization energies of radicals, SE(R ), along the simple series methyl/ethyl/i-propyl/t-butyl are known to vary in spread and even direction dependent on which dissociation enthalpies, DH(R-X), they are based on. Using a highly electronegative X is recognized as unwise, but it is not clear whether a choice of X = Me or X = R might not be preferred over the almost universal use of R = H. The enthalpies of isomerization of C4 radical pairs that vary only in the substitution pattern at the radical center but not in carbon skeleton illustrate that R = H is indeed the better choice. Comparisons in the context of recent predictive models for alkane and radical stability indicate that, while relative DH(R-H) values highlight the desired difference in substitution pattern at the radical center, relative DH(R-Me) values are perturbed by differences in skeletal branching or protobranching which are well-known to affect thermochemistry. As a result, SE(R ) values derived from relative DH(R-Me) values are consistently too small. The same pattern is illustrated for prim, sec, and tert allylic and benzylic radicals (larger SE(R )) and for the parent vinyl, phenyl, and ethynyl radicals (negative SE(R )).

  8. Fuzzy branching temporal logic.

    Science.gov (United States)

    Moon, Seong-ick; Lee, Kwang H; Lee, Doheon

    2004-04-01

    Intelligent systems require a systematic way to represent and handle temporal information containing uncertainty. In particular, a logical framework is needed that can represent uncertain temporal information and its relationships with logical formulae. Fuzzy linear temporal logic (FLTL), a generalization of propositional linear temporal logic (PLTL) with fuzzy temporal events and fuzzy temporal states defined on a linear time model, was previously proposed for this purpose. However, many systems are best represented by branching time models in which each state can have more than one possible future path. In this paper, fuzzy branching temporal logic (FBTL) is proposed to address this problem. FBTL adopts and generalizes concurrent tree logic (CTL*), which is a classical branching temporal logic. The temporal model of FBTL is capable of representing fuzzy temporal events and fuzzy temporal states, and the order relation among them is represented as a directed graph. The utility of FBTL is demonstrated using a fuzzy job shop scheduling problem as an example. PMID:15376850

  9. Right bundle branch block

    DEFF Research Database (Denmark)

    Bussink, Barbara E; Holst, Anders Gaarsdal; Jespersen, Lasse;

    2013-01-01

    AimsTo determine the prevalence, predictors of newly acquired, and the prognostic value of right bundle branch block (RBBB) and incomplete RBBB (IRBBB) on a resting 12-lead electrocardiogram in men and women from the general population.Methods and resultsWe followed 18 441 participants included.......5%/2.3% in women, P Right bundle branch block was associated with significantly...... increased all-cause and cardiovascular mortality in both genders with age-adjusted hazard ratios (HR) of 1.31 [95% confidence interval (CI), 1.11-1.54] and 1.87 (95% CI, 1.48-2.36) in the gender pooled analysis with little attenuation after multiple adjustment. Right bundle branch block was associated...

  10. 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.

  11. Tracheobronchial Branching Anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Min Ji; Kim, Young Tong; Jou, Sung Shick [Soonchunhyang University, Cheonan Hospital, Cheonan (Korea, Republic of); Park, A Young [Soonchunhyang University College of Medicine, Asan (Korea, Republic of)

    2010-04-15

    There are various congenital anomalies with respect to the number, length, diameter, and location of tracheobronchial branching patterns. The tracheobronchial anomalies are classified into two groups. The first one, anomalies of division, includes tracheal bronchus, cardiac bronchus, tracheal diverticulum, pulmonary isomerism, and minor variations. The second one, dysmorphic lung, includes lung agenesis-hypoplasia complex and lobar agenesis-aplasia complex

  12. Multimode geodesic branching components

    Science.gov (United States)

    Schulz, D.; Voges, E.

    1983-01-01

    Geodesic branching components are investigated for multimode guided wave optics. Geodesic structures with particular properties, e.g. focussing star couplers, are derived by a synthesis technique based on a theorem of Toraldo di Francia. Experimentally, the geodesic surfaces are printed on acrylic glass and are spin-coated with organic film waveguides.

  13. Size-exclusion chromatography (SEC) of branched polymers and polysaccharides

    OpenAIRE

    Gaborieau, Marianne; Castignolles, Patrice

    2010-01-01

    Branched polymers are among the most important polymers, ranging from polyolefins to polysaccharides. Branching plays a key role in the chain dynamics. It is thus very important for application properties such as mechanical and adhesive properties and digestibility. It also plays a key role in viscous properties, and thus in the mechanism of the separation of these polymers in size-exclusion chromatography (SEC). Critically reviewing the literature, particularly on SEC of polyolefins, polyacr...

  14. Single-chain antibody-fragment M6P-1 possesses a mannose 6-phosphate monosaccharide-specific binding pocket that distinguishes N-glycan phosphorylation in a branch-specific manner†.

    Science.gov (United States)

    Blackler, Ryan J; Evans, Dylan W; Smith, David F; Cummings, Richard D; Brooks, Cory L; Braulke, Thomas; Liu, Xinyu; Evans, Stephen V; Müller-Loennies, Sven

    2016-02-01

    The acquisition of mannose 6-phosphate (Man6P) on N-linked glycans of lysosomal enzymes is a structural requirement for their transport from the Golgi apparatus to lysosomes mediated by the mannose 6-phosphate receptors, 300 kDa cation-independent mannose 6-phosphate receptor (MPR300) and 46 kDa cation-dependent mannose 6-phosphate receptor (MPR46). Here we report that the single-chain variable domain (scFv) M6P-1 is a unique antibody fragment with specificity for Man6P monosaccharide that, through an array-screening approach against a number of phosphorylated N-glycans, is shown to bind mono- and diphosphorylated Man6 and Man7 glycans that contain terminal αMan6P(1 → 2)αMan(1 → 3)αMan. In contrast to MPR300, scFv M6P-1 does not bind phosphodiesters, monophosphorylated Man8 or mono- or diphosphorylated Man9 structures. Single crystal X-ray diffraction analysis to 2.7 Å resolution of Fv M6P-1 in complex with Man6P reveals that specificity and affinity is achieved via multiple hydrogen bonds to the mannose ring and two salt bridges to the phosphate moiety. In common with both MPRs, loss of binding was observed for scFv M6P-1 at pH values below the second pKa of Man6P (pKa = 6.1). The structures of Fv M6P-1 and the MPRs suggest that the change of the ionization state of Man6P is the main driving force for the loss of binding at acidic lysosomal pH (e.g. lysosome pH ∼ 4.6), which provides justification for the evolution of a lysosomal enzyme transport pathway based on Man6P recognition. PMID:26503547

  15. Electrochemical Energy Storage Branch

    Science.gov (United States)

    1985-01-01

    The activities of the Electrochemical Energy Storage Branch are highlighted, including the Technology Base Research and the Exploratory Technology Development and Testing projects within the Electrochemical Energy Storage Program for the 1984 fiscal year. General Headquarters activities are presented first; and then, a summary of the Director Controlled Milestones, followed by other major accomplishments. A listing of the workshops and seminars held during the year is also included.

  16. Tau leptonic branching ratios

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Garrido, L; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    A sample of 62249 \\tau-pair events is selected from data taken with the ALEPH detector in 1991, 1992 and 1993. The measurement of the branching fractions for \\tau decays into electrons and muons is presented with emphasis on the study of systematic effects from selection, particle identification and decay classification. Combined with the most recent ALEPH determination of the \\tau lifetime, these results provide a relative measurement of the leptonic couplings in the weak charged current for transverse W bosons.

  17. Modeling branching in cereals

    OpenAIRE

    Jochem B. Evers; Vos, Jan

    2013-01-01

    Cereals and grasses adapt their structural development to environmental conditions and the resources available. The primary adaptive response is a variable degree of branching, called tillering in cereals. Especially for heterogeneous plant configurations the degree of tillering varies per plant. Functional–structural plant modeling (FSPM) is a modeling approach allowing simulation of the architectural development of individual plants, culminating in the emergent behavior at the canopy level....

  18. Partial branching enzyme treatment increases the low glycaemic property and α-1,6 branching ratio of maize starch.

    Science.gov (United States)

    Li, Xingfeng; Miao, Ming; Jiang, Huan; Xue, Jiangchao; Jiang, Bo; Zhang, Tao; Gao, Yaqi; Jia, Yingmin

    2014-12-01

    Partial branching enzyme treatment was used to modulate the starch fine chain structure responsible for a high content of slowly digestible starch fraction. Normal maize starch modified using branching enzyme for 4h showed a maximum slowly digestible starch content of 23.90%. The branching enzyme hydrolysis decreased the amylose content from 32.8% to 12.8%. The molecular weight distribution of enzyme-treated starches showed a larger proportion of low molecular weight fractions appeared in the enzyme treated starch sample compare to native starch. The number of shorter chains (DP30) from 20.11% to 11.95%. (1)H NMR spectra showed an increase of α-1,6 branching ratio from 4.7% to 9.4% during enzyme treatment. The increase in the amount of shorter chains and more α-1,6 linkages likely contribute to their slow digestion property. These results suggest that starches treated with partial branching enzyme synthesis a novel branched structure with slowly digestible character.

  19. Synthesis and Characterization of Branched Poly(ester urea)s with Different Branch Density

    Science.gov (United States)

    Yu, Jiayi; Becker, Matthew

    2015-03-01

    A new class of L-phenylalanine-based poly(ester urea)s (PEU) was developed that possess tunable mechanical properties, water uptake ability and degradation rates. Our preliminary data has shown that 1,6-hexanediol L - phenylalanine-based poly(ester urea)s possesses an elastic modulus nearly double that of poly(lactic acid). My work details the synthesis of a series of L - phenylalanine-based poly(ester urea)s possessing a variation in diol chain length and in branch density and shows how these subtle structural differences influence the mechanical properties and in vitro biodegradation rates. The elastic moduli span a range of values that overlap with several currently clinically available degradable polymers. Increasingly the diol chain lengths increases the amount of flexible segment in the chemical structure, which results in reduced elastic modulus values and increased values of elongation at break. Increasing the amount of branch monomer incorporated into the system reduces the molecular entanglement, which also results in decreased elastic modulus values and increased values of elongation at break. The L - phenylalanine-based poly(ester urea)s also exhibited a diol length dependent degradation process that varied between 1-5 % over 16 weeks. Compared with PLLA, PEUs degrade more quickly and the rate can be tuned by changing the diol chain length. PEUs absorb more water and the water uptake ability can be tuned by changing the branch density. This work was supported by Akron Functional Materials Center.

  20. Thermal Energy Conversion Branch

    Science.gov (United States)

    Bielozer, Matthew C.; Schreiber, Jeffrey, G.; Wilson, Scott D.

    2004-01-01

    The Thermal Energy Conversion Branch (5490) leads the way in designing, conducting, and implementing research for the newest thermal systems used in space applications at the NASA Glenn Research Center. Specifically some of the most advanced technologies developed in this branch can be broken down into four main areas: Dynamic Power Systems, Primary Solar Concentrators, Secondary Solar Concentrators, and Thermal Management. Work was performed in the Dynamic Power Systems area, specifically the Stirling Engine subdivision. Today, the main focus of the 5490 branch is free-piston Stirling cycle converters, Brayton cycle nuclear reactors, and heat rejection systems for long duration mission spacecraft. All space exploring devices need electricity to operate. In most space applications, heat energy from radioisotopes is converted to electrical power. The Radioisotope Thermoelectric Generator (RTG) already supplies electricity for missions such as the Cassini Spacecraft. The focus of today's Stirling research at GRC is aimed at creating an engine that can replace the RTG. The primary appeal of the Stirling engine is its high system efficiency. Because it is so efficient, the Stirling engine will significantly reduce the plutonium fuel mission requirements compared to the RTG. Stirling is also being considered for missions such as the lunar/Mars bases and rovers. This project has focused largely on Stirling Engines of all types, particularly the fluidyne liquid piston engine. The fluidyne was developed by Colin D. West. This engine uses the same concepts found in any type of Stirling engine, with the exception of missing mechanical components. All the working components are fluid. One goal was to develop and demonstrate a working Stirling Fluidyne Engine at the 2nd Annual International Energy Conversion Engineering Conference in Providence, Rhode Island.

  1. Combustion Branch Website Development

    Science.gov (United States)

    Bishop, Eric

    2004-01-01

    The NASA combustion branch is a leader in developing and applying combustion science to focused aerospace propulsion systems concepts. It is widely recognized for unique facilities, analytical tools, and personnel. In order to better communicate the outstanding research being done in this Branch to the public and other research organization, a more substantial website was desired. The objective of this project was to build an up-to-date site that reflects current research in a usable and attractive manner. In order to accomplish this, information was requested from all researchers in the Combustion branch, on their professional skills and on the current projects. This information was used to fill in the Personnel and Research sections of the website. A digital camera was used to photograph all personnel and these photographs were included in the personnel section as well. The design of the site was implemented using the latest web standards: xhtml and external css stylesheets. This implementation conforms to the guidelines recommended by the w3c. It also helps to ensure that the web site is accessible by disabled users, and complies with Section 508 Federal legislation (which mandates that all Federal websites be accessible). Graphics for the new site were generated using the gimp (www.gimp.org) an open-source graphics program similar to Adobe Photoshop. Also, all graphics on the site were of a reasonable size (less than 20k, most less than 2k) so that the page would load quickly. Technologies such as Macromedia Flash and Javascript were avoided, as these only function on some clients which have the proper software installed or enabled. The website was tested on different platforms with many different browsers to ensure there were no compatibility issues. The website was tested on windows with MS IE 6, MSIE 5 , Netscape 7, Mozilla and Opera. On a Mac, the site was tested with MS IE 5 , Netscape 7 and Safari.

  2. Branch formation during organ development

    Science.gov (United States)

    Gjorevski, Nikolce; Nelson, Celeste M.

    2010-01-01

    Invertebrates and vertebrates use branching morphogenesis to build epithelial trees to maximize the surface area of organs within a given volume. Several molecular regulators of branching have recently been discovered, a number of which are conserved across different organs and species. Signals that control branching at the cellular and tissue levels are also starting to emerge, and are rapidly unveiling the physical nature of branch development. Here we discuss the molecular, cellular and physical processes that govern branch formation and highlight the major outstanding questions in the field. PMID:20890968

  3. Effects of Branched Chain Amino Acids or Fatty Acid Supplementation on in Vitro Fermentation of Corn Straw and Bacterial Diversity%添加支链氨基酸或支链脂肪酸对玉米秸秆体外瘤胃发酵和细菌多样性的影响

    Institute of Scientific and Technical Information of China (English)

    张慧玲; 李林; 陈勇; 许晓莉; 杨玉霞

    2012-01-01

    In vitro culture technique was adopted to study the effects of branched-chain amino acid (BCAA) or branched-chain volatile fatty acid (BCVFA) on fermentation of corn straw. Results showed that the concentration of total volatile fatty acid,acetic acid,propanoic acid,and butyric acid,and the degradation of dry matter (DM) and neutral detergent fiber (NDF) were not affected by 2 mmol/L BCAA or BCVFA supplementation. Compared with the BCVFA,BCAA supplementation tended to increase the concentrations of total volatile fatty acid (TVFA). Supplementation of valine (Val) and isobutyric acid increased the concentrations of isobutyric acid in the ruminal fluid by 2. 85 and 3. 12 fold ( P <0. 05). Addition of leucine (Leu) ,isovaleric acid,isoleucine (He) and 2-methylbutyric acid increased the concentration of isovaleric acid in the ruminal fluid by 2. 20 - 2. 50 fold ( P <0. 05). Compared with the BCVFA,supplementation of Val,Leu and He increased the concentration of valeric acid in ruminal fluid by 27. 69% ( P < 0. 05) ,25. 68% ( P <0. 05) and 39. 34% ( P <0. 05) respectively. Final pH decreased and degradation of DM and NDF of corn straw increased and the concentrations of TVFA,acetic acid,propanoic acid and butyric acid tended to increase by 4 mmol/L BCAA or BCVFA supplementation. Addition of isovaleric acid, He and 2-methylbutyric acid increased the concentrations of propanoic acid by 29. 94% ( P < 0. 05), 26. 31% ( P <0. 05) and 25. 00% ( P'<0. 05) respectively. Supplementation of Val and isobutyric acid increased the concentrations of isobutyric acid in the ruminal fluid by 5. 30 and 5. 45 fold ( P <0. 05). Addition of 4 mmol/L Leu,isovaleric acid,He and 2-methylbutyric acid increased the concentration of isovaleric acid in the ruminal fluid by 3. 76 — 4. 20 fold ( P <0. 05). Compared with the BCVFA, supplementation of 4 mmol/L Val,Leu and He increased the concentration of valeric acid in ruminal fluid by 22. 92% ( P < 0.05), 33. 33% (P<0. 05) and 55. 00% ( P <0. 05

  4. Periexercise coingestion of branched-chain amino acids and carbohydrate in men does not preferentially augment resistance exercise-induced increases in phosphatidylinositol 3 kinase/protein kinase B-mammalian target of rapamycin pathway markers indicative of muscle protein synthesis.

    Science.gov (United States)

    Ferreira, Maria Pontes; Li, Rui; Cooke, Matthew; Kreider, Richard B; Willoughby, Darryn S

    2014-03-01

    The effects of a single bout of resistance exercise (RE) in conjunction with periexercise branched-chain amino acid (BCAA) and carbohydrate (CHO) ingestion on skeletal muscle signaling markers indicative of muscle protein synthesis were determined. It was hypothesized that CHO + BCAA would elicit a more profound effect on these signaling markers compared with CHO. Twenty-seven males were randomly assigned to CHO, CHO + BCAA, or placebo (PLC) groups. Four sets of leg presses and leg extensions were performed at 80% 1 repetition maximum. Supplements were ingested 30 minutes and immediately before and after RE. Venous blood and muscle biopsy samples were obtained immediately before supplement ingestion and 0.5, 2, and 6 hours after RE. Serum insulin and glucose and phosphorylated levels of muscle insulin receptor substrate 1 (IRS-1), protein kinase B, mammalian target of rapamycin, phosphorylated 70S6 kinase, and 4E binding protein 1 were assessed. Data were analyzed by 2-way repeated-measures analysis of variance. Significant group × time interactions were observed for glucose and insulin (P protein kinase B (P = .031), mammalian target of rapamycin (P = .003), and phosphorylated 70S6 kinase (P = .001). Carbohydrate and CHO + BCAA supplementation significantly increased IRS-1 compared with PLC (P = .002). However, periexercise coingestion of CHO and BCAA did not augment RE-induced increases in skeletal muscle signaling markers indicative of muscle protein synthesis when compared with CHO.

  5. Starbucks Branches Out

    Institute of Scientific and Technical Information of China (English)

    Charies; Wang

    2006-01-01

    With 59 cafes in Beijing and Tianjin, Beijing Meida Coffee Co. Ltd. is an authorized licensee of Starbucks Coffee International Inc., a wholly-owned subsidiary of Seattle-based Starbucks Corp. Meida President Charles Wang spoke about the coffee chain's profits in China and its future plans in an interview with Beijing Review reporter Lan Xinzhen.

  6. Changes in fatty acid branching and unsaturation of Streptomyces griseus and Brevibacterium fermentans as a response to growth temperature.

    OpenAIRE

    Suutari, M; Laakso, S

    1992-01-01

    Streptomyces griseus showed three different modes of changing fatty acids in response to temperature change. In Brevibacterium fermentans, two such responses were found. The responses involved changes in fatty acid branching, unsaturation, or chain length, depending on growth temperature range. Changes in unsaturation of branched-chain acids were characteristic at low growth temperatures.

  7. Hydrocarbon metabolism by Brevibacterium erythrogenes: normal and branched alkanes.

    Science.gov (United States)

    Pirnik, M P; Atlas, R M; Bartha, R

    1974-09-01

    Branched- and straight-chain alkanes are metabolized by Brevibacterium erythrogenes by means of two distinct pathways. Normal alkanes (e.g., n-pentadecane) are degraded, after terminal oxidation, by the beta-oxidation system operational in fatty acid catabolism. Branched alkanes like pristane (2,6,10,14-tetramethylpentadecane) and 2-methylundecane are degraded as dicarboxylic acids, which also undergo beta-oxidation. Pristane-derived intermediates are observed to accumulate, with time, as a series of dicarboxylic acids. This dicarboxylic acid pathway is not observed in the presence of normal alkanes. Release of (14)CO(2) from [1-(14)C]pristane is delayed, or entirely inhibited, in the presence of n-hexadecane, whereas CO(2) release from n-hexadecane remains unaffected. These results suggest an inducible dicarboxylic acid pathway for degradation of branched-chain alkanes. PMID:4852318

  8. Path-valued branching processes and nonlocal branching superprocesses

    CERN Document Server

    Li, Zenghu

    2012-01-01

    A family of continuous-state branching processes with immigration are constructed as the solution flow of a stochastic equation system driven by time-space noises. The family can be regarded as an inhomogeneous increasing path-valued branching process with immigration. Two nonlocal branching immigration superprocesses can be defined from the flow. We identify explicitly the branching and immigration mechanisms of those processes. The results provide new perspectives into the tree-valued Markov processes of Aldous and Pitman [Ann. Inst. H. Poincare Probab. Statist. 34 (1998), 637--686] and Abraham and Delmas [Ann. Probab. To appear].

  9. The branched-chain amino acid requerement in neonates

    NARCIS (Netherlands)

    F. Maingay-de Groof (Femke)

    2012-01-01

    textabstractGrowth during the earliest stages of life is an important determinant of an individual’s later health and risk of chronic disease. Substantial evidence shows that growth in the first 2 years of life, especially high early weight gain, is associated with adverse health outcomes later in l

  10. Branched-chain amino acids for people with hepatic encephalopathy

    DEFF Research Database (Denmark)

    Gluud, Lise Lotte; Dam, Gitte; Les, Iñigo;

    2015-01-01

    ), lactulose (two trials), or neomycin (two trials). In 15 trials, all participants had cirrhosis. Based on the combined Cochrane Hepato-Biliary Group score, we classed seven trials as low risk of bias and nine trials as high risk of bias (mainly due to lack of blinding or for-profit funding). In a random...... not identify predictors of the intervention effect in the subgroup, sensitivity, or meta-regression analyses. In sensitivity analyses that excluded trials with a lactulose or neomycin control, BCAA had a beneficial effect on hepatic encephalopathy (RR 0.76, 95% CI 0.63 to 0.92). Additional sensitivity analyses...... found no difference between BCAA and lactulose or neomycin (RR 0.66, 95% CI 0.34 to 1.30). AUTHORS' CONCLUSIONS: In this updated review, we included five additional trials. The analyses showed that BCAA had a beneficial effect on hepatic encephalopathy. We found no effect on mortality, quality of life...

  11. Branched-chain amino acids for people with hepatic encephalopathy

    DEFF Research Database (Denmark)

    Gluud, Lise Lotte; Dam, Gitte; Les, Iñigo;

    2015-01-01

    ), lactulose (two trials), or neomycin (two trials). In 15 trials, all participants had cirrhosis. We classed seven trials as low risk of bias and nine trials as high risk of bias (mainly due to lack of blinding or for-profit funding). In a random-effects meta-analysis of mortality, we found no difference...... in the subgroup, sensitivity, or meta-regression analyses. In sensitivity analyses that excluded trials with a lactulose or neomycin control, BCAA had a beneficial effect on hepatic encephalopathy (RR 0.76, 95% CI 0.63 to 0.92). Additional sensitivity analyses found no difference between BCAA and lactulose...... or neomycin (RR 0.66, 95% CI 0.34 to 1.30). AUTHORS' CONCLUSIONS: In this updated review, we included five additional trials. The analyses showed that BCAA had a beneficial effect on hepatic encephalopathy. We found no effect on mortality, quality of life, or nutritional parameters, but we need additional...

  12. Branched chain amino acids requirements and metabolism in pigs

    DEFF Research Database (Denmark)

    Assadi Soumeh, Elham

    2015-01-01

    reasons: first, BCAA share the same enzymes in their catabolic pathways, and there is an interaction among them in a way that excess Leu for example increases the catabolism of them all and changes the requirements. Second, BCAA are not only building blocks of protein biosynthesis, but are also involved......, and Leu requirements in ratio to Lys for pigs after weaning and second, to study the metabolic profile in blood and urine of pigs fed with different BCAA in the diet, and finally, to identify the biomarkers of BCAA, when pigs were fed with the optimum dietary BCAA level to support the best growth...... of the last “-omics”, is a global analysis and interpretation of metabolome in specific health or nutritional status. Non-targeted metabolomics is used for screening the metabolic profile, and the metabolic signature could be used for hypothesis generation. The results of a non-targeted LC-MS metabolomics...

  13. Quiver Varieties and Branching

    Directory of Open Access Journals (Sweden)

    Hiraku Nakajima

    2009-01-01

    Full Text Available Braverman and Finkelberg recently proposed the geometric Satake correspondence for the affine Kac-Moody group Gaff [Braverman A., Finkelberg M., arXiv:0711.2083]. They conjecture that intersection cohomology sheaves on the Uhlenbeck compactification of the framed moduli space of Gcpt-instantons on $R^4/Z_r$ correspond to weight spaces of representations of the Langlands dual group $G_{aff}^{vee}$ at level $r$. When $G = SL(l$, the Uhlenbeck compactification is the quiver variety of type $sl(r_{aff}$, and their conjecture follows from the author's earlier result and I. Frenkel's level-rank duality. They further introduce a convolution diagram which conjecturally gives the tensor product multiplicity [Braverman A., Finkelberg M., Private communication, 2008]. In this paper, we develop the theory for the branching in quiver varieties and check this conjecture for $G = SL(l$.

  14. Falling chains

    Science.gov (United States)

    Wong, Chun Wa; Yasui, Kosuke

    2006-06-01

    The one-dimensional fall of a folded chain with one end suspended from a rigid support and a chain falling from a resting heap on a table is studied. Because their Lagrangians contain no explicit time dependence, the falling chains are conservative systems. Their equations of motion are shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is incorrect because it neglects the energy gained when a link leaves a subchain. The maximum chain tension measured by Calkin and March for the falling folded chain is given a simple if rough interpretation. Other aspects of the falling folded chain are briefly discussed.

  15. Methods and Technologies Branch (MTB)

    Science.gov (United States)

    The Methods and Technologies Branch focuses on methods to address epidemiologic data collection, study design and analysis, and to modify technological approaches to better understand cancer susceptibility.

  16. REPAIR OF FINGER SOFT TISSUE DEFECT WITH ISLAND FLAP BASED ON VASCULAR CHAIN OF CUTANEOUS BRANCH OF DORSAL METACARPAL ARTERY%指蹼动脉分支蒂掌背链状血管皮瓣修复手指软组织缺损

    Institute of Scientific and Technical Information of China (English)

    张文静; 张文龙; 焦成; 刘亚静

    2013-01-01

    Objective To investigate the operative procedure and the clinical results of the island flap based on the vascular chain of the cutaneous branch of dorsal metacarpal artery for repairing finger soft tissue defect. Methods Between January 2008 and March 2012, 28 cases of tissue defect of fingers (32 fingers) were repaired with the island flaps based on the vascular chain of the cutaneous branch of dorsal metacarpal artery. There were 20 males (23 fingers) and 8 females (9 fingers), with an average age of 29.5 years (range, 14-67 years). The injury causes included 14 cases of crush injury, 6 cases of pressing injury, 5 cases of cutting injury, and 3 cases of avulsion injury. The locations included 10 index fingers, 13 long fingers, 6 ring fingers, and 3 little fingers. There were 9 defects of proximal segment, 12 defects of middle segment, and 11 defects of distal segment. The area of defect ranged from 1.0 cm x 0.8 cm to 5.2 cm x 3.5 cm. The disease duration was 1 hour to 15 days. The area of flaps ranged from 1.2 cm × 1.0 cm to 5.5 cm × 3.8 cm. The donors were closed by suture or were repaired with skin graft. Results Tense blister occurred in 3 cases, which was cured after dressing change; the other flaps survived. Wound obtained primary healing. Twenty-five patients (27 fingers) were followed up 6-25 months (mean, 16.8 months). The flaps had soft texture and satisfactory appearance. Two point discrimination was 6-9 mm (mean, 7.7 mm) at 6 months after operation. The total active movement of fingers was 105-230° (mean, 204.6°). The results were excellent in 17 fingers, good in 8 fingers, and fair in 2 fingers with an excellent and good rate of 92.6%. Conclusion The island flap based on the vascular chain of the cutaneous branch of dorsal metacarpal artery has the advantages of the deverting point from the dorsal point to the palm, the extended vessel pedicle, and expanded operation indications, so it is not necessary to cut the dorsal metacarpal artery. It can

  17. Tau hadronic branching ratios

    CERN Document Server

    Buskulic, Damir; De Bonis, I; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Odier, P; Pietrzyk, B; Ariztizabal, F; Chmeissani, M; Crespo, J M; Efthymiopoulos, I; Fernández, E; Fernández-Bosman, M; Gaitan, V; Martínez, M; Orteu, S; Pacheco, A; Padilla, C; Palla, Fabrizio; Pascual, A; Perlas, J A; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Farilla, A; Gelao, G; Girone, M; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Natali, S; Nuzzo, S; Ranieri, A; Raso, G; Romano, F; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Bonvicini, G; Cattaneo, M; Comas, P; Coyle, P; Drevermann, H; Engelhardt, A; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Jacobsen, R; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Markou, C; Martin, E B; Mato, P; Minten, Adolf G; Miquel, R; Oest, T; Palazzi, P; Pater, J R; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schneider, O; Tejessy, W; Tomalin, I R; Venturi, A; Wachsmuth, H W; Wiedenmann, W; Wildish, T; Witzeling, W; Wotschack, J; Ajaltouni, Ziad J; Bardadin-Otwinowska, Maria; Barrès, A; Boyer, C; Falvard, A; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rossignol, J M; Saadi, F; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Kyriakis, A; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Passalacqua, L; Rougé, A; Rumpf, M; Tanaka, R; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Delfino, M C; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Pepé-Altarelli, M; Dorris, S J; Halley, A W; ten Have, I; Knowles, I G; Lynch, J G; Morton, W T; O'Shea, V; Raine, C; Reeves, P; Scarr, J M; Smith, K; Smith, M G; Thompson, A S; Thomson, F; Thorn, S; Turnbull, R M; Becker, U; Braun, O; Geweniger, C; Graefe, G; Hanke, P; Hepp, V; Kluge, E E; Putzer, A; Rensch, B; Schmidt, M; Sommer, J; Stenzel, H; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Colling, D J; Dornan, Peter J; Konstantinidis, N P; Moneta, L; Moutoussi, A; Nash, J; San Martin, G; Sedgbeer, J K; Stacey, A M; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Bowdery, C K; Brodbeck, T J; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Whelan, E P; Williams, M I; Galla, A; Greene, A M; Kleinknecht, K; Quast, G; Raab, J; Renk, B; Sander, H G; Wanke, R; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Bencheikh, A M; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Diaconu, C A; Etienne, F; Thulasidas, M; Nicod, D; Payre, P; Rousseau, D; Talby, M; Abt, I; Assmann, R W; Bauer, C; Blum, Walter; Brown, D; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Jakobs, K; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Wolf, G; Alemany, R; Boucrot, J; Callot, O; Cordier, A; Courault, F; Davier, M; Duflot, L; Grivaz, J F; Heusse, P; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Musolino, G; Nikolic, I A; Park, H J; Park, I C; Schune, M H; Simion, S; Veillet, J J; Videau, I; Abbaneo, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Rizzo, G; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Triggiani, G; Vannini, C; Verdini, P G; Walsh, J; Betteridge, A P; Blair, G A; Bryant, L M; Cerutti, F; Gao, Y; Green, M G; Johnson, D L; Medcalf, T; Mir, L M; Perrodo, P; Strong, J A; Bertin, V; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Edwards, M; Maley, P; Norton, P R; Thompson, J C; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Marx, B; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Beddall, A; Booth, C N; Boswell, R; Cartwright, S L; Combley, F; Dawson, I; Köksal, A; Letho, M; Newton, W M; Rankin, C; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Feigl, E; Grupen, Claus; Lutters, G; Minguet-Rodríguez, J A; Rivera, F; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Ragusa, F; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Bellantoni, L; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Harton, J L; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Schmitt, M; Scott, I J; Sharma, V; Turk, J; Walsh, A M; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1996-01-01

    From 64492 selected \\tau-pair events, produced at the Z^0 resonance, the measurement of the tau decays into hadrons from a global analysis using 1991, 1992 and 1993 ALEPH data is presented. Special emphasis is given to the reconstruction of photons and \\pi^0's, and the removal of fake photons. A detailed study of the systematics entering the \\pi^0 reconstruction is also given. A complete and consistent set of tau hadronic branching ratios is presented for 18 exclusive modes. Most measurements are more precise than the present world average. The new level of precision reached allows a stringent test of \\tau-\\mu universality in hadronic decays, g_\\tau/g_\\mu \\ = \\ 1.0013 \\ \\pm \\ 0.0095, and the first measurement of the vector and axial-vector contributions to the non-strange hadronic \\tau decay width: R_{\\tau ,V} \\ = \\ 1.788 \\ \\pm \\ 0.025 and R_{\\tau ,A} \\ = \\ 1.694 \\ \\pm \\ 0.027. The ratio (R_{\\tau ,V} - R_{\\tau ,A}) / (R_{\\tau ,V} + R_{\\tau ,A}), equal to (2.7 \\pm 1.3) \\ \\%, is a measure of the importance of Q...

  18. Unwrapping Chains

    CERN Document Server

    Cambou, A D; Hamm, E; Hanna, J A; Menon, N; Santangelo, C D; Walsh, L

    2012-01-01

    A loop of chain can move along its own tangents, maintaining a steady shape. An open-ended chain undergoing a nontrivial motion must change its shape. One consequence is that chains pulled around objects will fail to follow the contours of the objects, unwrapping themselves instead. This short note accompanies a fluid dynamics video submission (83068) to the APS DFD Gallery of Fluid Motion 2012.

  19. Falling chains

    CERN Document Server

    Wong, C W; Wong, Chun Wa; Yasui, Kosuke

    2006-01-01

    The one-dimensional falling motion of a bungee chain suspended from a rigid support and of a chain falling from a resting heap on a table is studied. Their Lagrangians are found to contain no explicit time dependence. As a result, these falling chains are conservative systems. Each of their Lagrange's equations of motion is shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show in particular that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is incorrect because it neglects the energy gained when the transferred link is emitted by the emitting subchain. The maximum chain tension measured by Calkin and March for the falling bungee chain is given a simple if rough interpretation. In the simplified one-dimensional treatment, the kinetic energy of the center of mass of the falling bungee chain is found to be converted by the chain tension at the rigid support into the internal kinetic energy of the chain. However, as t...

  20. Size-exclusion chromatography (SEC) of branched polymers and polysaccharides.

    Science.gov (United States)

    Gaborieau, Marianne; Castignolles, Patrice

    2011-02-01

    Branched polymers are among the most important polymers, ranging from polyolefins to polysaccharides. Branching plays a key role in the chain dynamics. It is thus very important for application properties such as mechanical and adhesive properties and digestibility. It also plays a key role in viscous properties, and thus in the mechanism of the separation of these polymers in size-exclusion chromatography (SEC). Critically reviewing the literature, particularly on SEC of polyolefins, polyacrylates and starch, we discuss common pitfalls but also highlight some unexplored possibilities to characterize branched polymers. The presence of a few long-chain branches has been shown to lead to a poor separation in SEC, as evidenced by multiple-detection SEC or multidimensional liquid chromatography. The local dispersity can be large in that case, and the accuracy of molecular weight determination achieved by current methods is poor, although hydrodynamic volume distributions offer alternatives. In contrast, highly branched polymers do not suffer from this extensive incomplete separation in terms of molecular weight. PMID:20967430

  1. Separation of complex branched polymers by size-exclusion chromatography probed with multiple detection.

    Science.gov (United States)

    Gaborieau, Marianne; Nicolas, Julien; Save, Maud; Charleux, Bernadette; Vairon, Jean-Pierre; Gilbert, Robert G; Castignolles, Patrice

    2008-05-01

    Size-exclusion chromatography (SEC) separates polymers by hydrodynamic volume (the universal calibration principle). Molecular weights can be determined using viscometry (relying on universal calibration) and light scattering (independent of universal calibration). In the case of complex branched polyacrylates with tetrahydrofuran as eluent, universal calibration is valid, although the separation in term of molecular weight is incomplete: a given elution slice contains a range of molecular weights, described in terms of a 'local polydispersity'. The local polydispersity index decreases when the number of branches per chain increases and complete separation is reached for highly branched chains. PMID:18378255

  2. Continuous-state branching processes

    CERN Document Server

    Li, Zenghu

    2012-01-01

    These notes were used in a short graduate course on branching processes the author gave in Beijing Normal University. The following main topics are covered: scaling limits of Galton--Watson processes, continuous-state branching processes, extinction probabilities, conditional limit theorems, decompositions of sample paths, martingale problems, stochastic equations, Lamperti's transformations, independent and dependent immigration processes. Some of the results are simplified versions of those in the author's book "Measure-valued branching Markov processes" (Springer, 2011). We hope these simplified results will set out the main ideas in an easy way and lead the reader to a quick access of the subject.

  3. The Observation on Clinical Application of Sugar, Whey Protein, and Branched- Chain Amino Acids Supplement for Athletes%运动员补糖、支链氨基酸和乳清蛋白的临床应用观察

    Institute of Scientific and Technical Information of China (English)

    胡斌; 侯菊花; 张立新

    2012-01-01

    Objective: To observe the supplement of sugar drinks, whey protein, bran6hed - chain amino acids and other substances on the stage of the heavy load training to maintain or improve physical function and fatigue recovery. Methods : Arranged 10 athletes in the 30d Sanda physical training phase of the winter training stage, ac- cording to the nutritional supplement program for energy supplement, Selected the indexes of the output of the total body anaerobic power, maximum power, fatigue index, a ability to pull oxygen paddle time, power, paddle fre- quency, biochemical indicators of blood lactate (LA) blood urea nitrogen (BUN), glucose (GL), creatine ki- nase (CK) as the observation, Alternative 10 teammates as the control group, and observed the different before and after the training. Results: The total output power, maximum power after the training had significantly in- creased (P 〈 0.01 ) than before added of the observed team. Compared with the control group after added the ath- letes fatigue index and the paddle frequency was also improved significantly (P 〈 O. 05), and after -school train- ing blood glucose levels also had significantly increased (P 〈 0.05). The blood BUN and the recovery had signif- icant improvement (P 〈0. 001 ) more than the control groups after added whey protein, branched- chain amino acids. Conclusion: The training period added sugar, whey protein, branched -chain amino acids and substances such as energy, could significantly improve the athlete's aerobic capacity and anaerobic exercise performance, could significantly delayed the occurrence of exercise - induced fatigue and accelerate recovery of the exercise - induced fatigue.%目的:观察补充糖饮料、支链氨基酸和乳清蛋白等能量物质对阶段性大运动量训练维持或提高运动员身体机能和疲劳恢复的影响。方法:根据冬训阶段性训练计划安排,对10名散打运动员在30d的体能训

  4. Left bundle-branch block

    DEFF Research Database (Denmark)

    Risum, Niels; Strauss, David; Sogaard, Peter;

    2013-01-01

    The relationship between myocardial electrical activation by electrocardiogram (ECG) and mechanical contraction by echocardiography in left bundle-branch block (LBBB) has never been clearly demonstrated. New strict criteria for LBBB based on a fundamental understanding of physiology have recently...

  5. Radiation effects on branched polysilanes

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, K.; Seki, S.; Tagawa, S. [Osaka Univ., Ibaraki (Japan). Inst. of Scientific and Industrial Research; Shibata, H.; Iwai, T. [Tokyo Univ. (Japan). Research Center for Nuclear Science and Technology

    2000-03-01

    We observed crosslinking and scission caused by gamma radiation in linear and branched polysilanes which have from 5% to 33% of the branching points. The crosslinking reactions become predominant for the irradiation with branching density increasing. The cleavage did not take place exclusively at the branching points and branching polysilanes are sensitive to radiation extraordinary as compared with linear polysilane from a careful study of the radiolysis products of a series of polysilanes. This is due to the increasing Si {center_dot} contributing to the crosslinking reaction and that they are not resonance-stabilized by double bonds as the reaction mechanism in the irradiated polysilanes. However, the gelation curve in linear PMPS irradiated by 2 MeV He{sup +} is almost consistent with that in branching PMPS, indicating that the size of chemical track is responsible for the gel fraction. The crosslinking G value for high molecular weight PMPS irradiated by 2 MeV He{sup +} was drastically decreased as compared with that for low molecular weight. It suggests that there are a large number of intramolecular crosslinking points for high molecular weight PMPS. (author)

  6. 补充支链氨基酸对失眠老年大鼠行为和糖代谢的影响%Effects of branched-chain amino acids supplementation on behaviour and glucose metabolism in aged rats subjected to in- somnia(

    Institute of Scientific and Technical Information of China (English)

    欧阳儒颖; 张济生; 蔡懿灵

    2014-01-01

    Objectives To explore the effects of branched-chain amino acids( BCAA) supplementation on behaviour and glucose metabolism in aged rats subjected to isomnia.Methods Experimental model of isomnia was established by use of sleep deprivation method(flower pot),thirty aged male rats were divided into five groups randomly:C(control)group, 6h(6 hours sleep per day) group, 6hB(6 hours sleep per day and fed fodder enriched with BCAA)group,4h(4 hours sleep per day)group and 4hB group.Re-sults Time of resting on the center lattic,number of make-up and number of excrete were significantly increased in experimental groups compared with C group(PC group>4h group(P0.05).Conpared with C group,the level of FPG in experimential groups were increased apparently (P4h (P<0.05).Conclusions supplementation of BCAA may ameliorates behavior and glucose metabolism in aged rats subjected to isomnia.%目的:探讨补充支链氨基酸( branched-chain amino acids,BCAA)对失眠老年大鼠行为和糖代谢的影响。方法采用小平台水环境的睡眠剥夺方法建立动物失眠模型,30只雄性老年大鼠随机分为对照组( C组)、6h组(每天6小时睡眠组)、6hB组(每天睡眠6小时,进食添加BCAA的饲料),4h组(每天睡眠4小时),4hB组(每天睡眠4小时,进食添加BCAA的饲料)。结果实验组大鼠的修饰行为次数、中央格停留时间、粪便颗粒数均高于C组,差异具有显著性( P<0.05)。且修饰行为次数、中央格停留时间4hB组<4h组(P<0.05);旷场实验得分6h组>C组>4h组,差异具有显著性(P<0.05)。但旷场实验得分、粪便颗粒数6h组与6hB组,4h组与4hB组比较无差异(P>0.05)。与C组比较,实验组的FPG水平显著升高(P<0.05);但4hB组<4h组(P<0.05)。与C组比较4h组和4hB组的血清INS水平显著升高(P<0.05),且4hB组<4h组(P<0.05)。与C组比较,

  7. Vibration analysis of pipelines with arbitrary branches by absorbing transfer matrix method

    Science.gov (United States)

    Liu, Gongmin; Li, Shuaijun; Li, Yanhua; Chen, Hao

    2013-11-01

    Branched pipes of arbitrary shapes are prevalent in pipe systems. Considering fluid-structure interaction (FSI), an absorbing transfer matrix method in frequency domain for fluid-filled pipelines with any branched pipes is proposed in this paper. A dominant chain of pipeline would be selected, and the point transfer matrix of each junction on the dominant chain would be determined. Here, the point transfer matrix, representing the influence of branched pipes at the junction on the dominant pipeline, was "absorbed" by the dominant chain. Based on these, with transfer matrixes of other elements, the fluid and structure dynamics problem could be solved following the chain transfer matrix method process. Several numerical examples with different constraints are presented to illustrate the application of the proposed method. Moreover, the experiment of cross-shaped pipes with various boundary conditions was carried out. And results from the present approach were validated by measured and numerical data. Then, the forced vibrations of branched pipes were analyzed by considering the effects of various parameters, which shows the fluid pressure and vibrations can be optimized by changing the branch angles and positions. Through these examples, it is shown that the proposed method is efficient and can be used to calculate branched pipes of any shape.

  8. Chain Gang

    Science.gov (United States)

    2006-01-01

    6 August 2006 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a chain of clustered and battered craters. These were formed by secondary impact. That is, somewhere to the south (beyond the bottom of this image), a large impact crater formed. When this occurred, material ejected from the crater was thrown tens to hundreds of kilometers away. This material then impacted the martian surface, forming clusters and chains of smaller craters. Location near: 15.8oN, 35.6oW Image width: 3 km (1.9 mi) Illumination from: upper left Season: Northern Spring

  9. Apical constriction initiates new bud formation during monopodial branching of the embryonic chicken lung

    Science.gov (United States)

    Kim, Hye Young; Varner, Victor D.; Nelson, Celeste M.

    2013-01-01

    Branching morphogenesis sculpts the airway epithelium of the lung into a tree-like structure to conduct air and promote gas exchange after birth. In the avian lung, a series of buds emerges from the dorsal surface of the primary bronchus via monopodial branching to form the conducting airways; anatomically, these buds are similar to those formed by domain branching in the mammalian lung. Here, we show that monopodial branching is initiated by apical constriction of the airway epithelium, and not by differential cell proliferation, using computational modeling and quantitative imaging of embryonic chicken lung explants. Both filamentous actin and phosphorylated myosin light chain were enriched at the apical surface of the airway epithelium during monopodial branching. Consistently, inhibiting actomyosin contractility prevented apical constriction and blocked branch initiation. Although cell proliferation was enhanced along the dorsal and ventral aspects of the primary bronchus, especially before branch formation, inhibiting proliferation had no effect on the initiation of branches. To test whether the physical forces from apical constriction alone are sufficient to drive the formation of new buds, we constructed a nonlinear, three-dimensional finite element model of the airway epithelium and used it to simulate apical constriction and proliferation in the primary bronchus. Our results suggest that, consistent with the experimental results, apical constriction is sufficient to drive the early stages of monopodial branching whereas cell proliferation is dispensable. We propose that initial folding of the airway epithelium is driven primarily by apical constriction during monopodial branching of the avian lung. PMID:23824575

  10. Synthesis and characterization of an exact comb polyisoprene with three branches having the middle branch twice the molecular weight of the other two identical external branches

    KAUST Repository

    Ratkanthwar, Kedar

    2013-01-01

    An exact comb polyisoprene (PI) with three branches, with the middle branch having twice the molecular weight of the two other identical external branches, was synthesized by using anionic polymerization high vacuum techniques and appropriate chlorosilane chemistry. The synthetic approach involves (a) the selective replacement of the two chlorines of 4-(dichloromethylsilyl) diphenylethylene (DCMSDPE, key molecule) with identical PI chains by titration with PILi, (b) the addition of sec-BuLi to the double bond of DPE followed by the polymerization of isoprene from the newly created anionic site to form a 3-arm living star PI, (c) the selective replacement of the two chlorines of trichloromethylsilane with 3-arm star PI to form an H-shape intermediate, and (d) the replacement of the remaining chlorine of trichloromethylsilane by linear PI chains with double the molecular weight. All intermediate and final products were characterized via size exclusion chromatography, temperature gradient interaction chromatography and 1H-NMR spectroscopy. As expected, due to the inability to control the exact stoichiometry of the linking reactants, the main product (exact comb PI) is contaminated by a few by-products, despite the fact that anionic polymerization is the most efficient way to produce well-defined polymers. © 2013 The Royal Society of Chemistry.

  11. Multiple pathways regulate shoot branching

    Directory of Open Access Journals (Sweden)

    Catherine eRameau

    2015-01-01

    Full Text Available Shoot branching patterns result from the spatio-temporal regulation of axillary bud outgrowth. Numerous endogenous, developmental and environmental factors are integrated at the bud and plant levels to determine numbers of growing shoots. Multiple pathways that converge to common integrators are most probably involved. We propose several pathways involving not only the classical hormones auxin, cytokinins and strigolactones, but also other signals with a strong influence on shoot branching such as gibberellins, sugars or molecular actors of plant phase transition. We also deal with recent findings about the molecular mechanisms and the pathway involved in the response to shade as an example of an environmental signal controlling branching. We propose the TCP transcription factor TB1/BRC1 and the polar auxin transport stream in the stem as possible integrators of these pathways. We finally discuss how modeling can help to represent this highly dynamic system by articulating knowledges and hypothesis and calculating the phenotype properties they imply.

  12. Warped branches of flux compactifications

    CERN Document Server

    Lim, Yen-Kheng

    2012-01-01

    We consider Freund-Rubin-type compactifications which are described by (p+q)-dimensional Einstein gravity with a positive cosmological constant and a q-form flux. Using perturbative expansions of Kinoshita's ansatz for warped dS_pxS^q and AdS_pxS^q spacetimes, we obtain analytical solutions describing the warped branches and their respective phase spaces. These equations are given by inhomogeneous Gegenbauer differential equations which can be solved by the Green's function method. The requirement that the Green's functions are regular provides constraints which determine the structure of the phase space of the warped branches. We apply the perturbation results to calculate the thermodynamic variables for the warped dS_pxS^q branch. In particular, the first law of thermodynamics can be reproduced using this method.

  13. Chain Teleportation

    OpenAIRE

    Lee, Chien-er

    2004-01-01

    By means of the idea of measurements on the crossed space-time nonlocal observables, we extend the mechanism for the two-way quantum teleportation to the chain teleportation among N spatially separated spin-1/2 systems. Since in the process only the local interactions are used, the microcausality is automatically satisfied.

  14. Dual chain synthetic heparin-binding growth factor analogs

    Science.gov (United States)

    Zamora, Paul O.; Pena, Louis A.; Lin, Xinhua

    2009-10-06

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  15. Dual chain synthetic heparin-binding growth factor analogs

    Energy Technology Data Exchange (ETDEWEB)

    Zamora, Paul O. (Gaithersburg, MD); Pena, Louis A. (Poquott, NY); Lin, Xinhua (Plainview, NY)

    2012-04-24

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  16. Influence of chain topology and bond potential on the glass transition of polymer chains simulated with the bond fluctuation model

    Energy Technology Data Exchange (ETDEWEB)

    Freire, J J [Departamento de Ciencias y Tecnicas FisicoquImicas, Facultad de Ciencias, Universidad Nacional de Educacion a Distancia (UNED), Senda del Rey 9, 28040 Madrid (Spain)], E-mail: jfreire@invi.uned.es

    2008-07-16

    The bond fluctuation model with a bond potential has been applied to investigation of the glass transition of linear chains and chains with a regular disposition of small branches. Cooling and subsequent heating curves are obtained for the chain energies and also for the mean acceptance probability of a bead jump. In order to mimic different trends to vitrification, a factor B gauging the strength of the bond potential with respect to the long-range potential (i.e. the intramolecular or intermolecular potential between indirectly bonded beads) has been introduced. (A higher value of B leads to a preference for the highest bond lengths and a higher total energy, implying a greater tendency to vitrify.) Different cases have been considered for linear chains: no long-range potential, no bond potential and several choices for B. Furthermore, two distinct values of B have been considered for alternate bonds in linear chains. In the case of the branched chains, mixed models with different values of B for bonds in the main chain and in the branches have also been investigated. The possible presence of ordering or crystallization has been characterized by calculating the collective light scattering function of the different samples after annealing at a convenient temperature below the onset of the abrupt change in the curves associated with a thermodynamic transition. It is concluded that ordering is inherited more efficiently in the systems with branched chains and also for higher values of B. The branched molecules with the highest B values in the main chain bonds exhibit two distinct transitions in the heating curves, which may be associated with two glass transitions. This behavior has been detected experimentally for chains with relatively long flexible branches.

  17. Relationship between Contents of Milk Fat Odd-and Branched-Chain Fatty Acids and Rumen Fluid Volatile Fatty Acids%乳脂奇数和支链脂肪酸含量与瘤胃液挥发性脂肪酸含量的关系

    Institute of Scientific and Technical Information of China (English)

    刘可园; 王晓帆; 丁雪; 郝小燕; 张永根; 辛杭书

    2016-01-01

    本试验旨在确定乳脂奇数和支链脂肪酸( OBCFA)含量与瘤胃挥发性脂肪酸( VFA)含量的关系。选择同一胎次体重相近的健康荷斯坦奶牛,处于产奶初期、中期和晚期的各3头(同一时期奶牛产奶量相近)。采集的12 h内的瘤胃液和乳样本,分别测定瘤胃液中VFA的含量和乳脂OBCFA的含量。结果表明:瘤胃液中各种VFA含量均能找到与之显著或极显著相关的OBCFA含量( P≤0.05或P≤0.01)。以乳脂OBCFA含量预测乙酸、丙酸和丁酸含量的回归方程的均方根误差分别为1.57、1.06和0.33,预测异丁酸、异戊酸和戊酸的为0.13。结果提示,以乳脂OBCFA含量为基础得到的预测瘤胃液中各种VFA含量的回归方程可以应用于瘤胃内VFA含量的预测。%The objective of this experiment were to determine whether a relationship existed between the con-tents of volatile fatty acids ( VFAs) in rumen fluid and odd-and branched-chain fatty acids ( OBCFAs) in milk fat.Nine healthy lactating Holstein dairy cows with same parity and similar body weight were selected, which were at early, middle and late lactation period ( 3 cows per period) , respectively, and cows of the same period had similar milk production.Rumen fluid and milk samples of 12 h were collected to determine the contents of VFAs in rumen fluid and OBCFAs in milk fat.The results showed that OBCFA contents significantly correlated with individual VFA contents could be found ( P≤0.05 or P≤0.01) .The root mean square error of the regres-sion equations, which were used to predict the contents of acetate, propionate, isobutyrate, butyrate, isovaler-ate and valerate in rumen fluid using milk fat OBCFA contents, were 1.57, 1.06, 0.13, 0.33, 0.13 and 0.13, respectively.The results suggest that the currently developed prediction equations based on milk OBCFA con-tents show potential to predict the contents of individual VFAs in rumen fluid.

  18. Detection of a branched alkyl molecule in the interstellar medium: iso-propyl cyanide

    CERN Document Server

    Belloche, Arnaud; Müller, Holger S P; Menten, Karl M

    2014-01-01

    The largest non-cyclic molecules detected in the interstellar medium (ISM) are organic with a straight-chain carbon backbone. We report an interstellar detection of a branched alkyl molecule, iso-propyl cyanide (i-C3H7CN), with an abundance 0.4 times that of its straight-chain structural isomer. This detection suggests that branched carbon-chain molecules may be generally abundant in the ISM. Our astrochemical model indicates that both isomers are produced within or upon dust grain ice mantles through the addition of molecular radicals, albeit via differing reaction pathways. The production of iso-propyl cyanide appears to require the addition of a functional group to a non-terminal carbon in the chain. Its detection therefore bodes well for the presence in the ISM of amino acids, for which such side-chain structure is a key characteristic.

  19. Branching of keratin intermediate filaments.

    Science.gov (United States)

    Nafeey, Soufi; Martin, Ines; Felder, Tatiana; Walther, Paul; Felder, Edward

    2016-06-01

    Keratin intermediate filaments (IFs) are crucial to maintain mechanical stability in epithelial cells. Since little is known about the network architecture that provides this stiffness and especially about branching properties of filaments, we addressed this question with different electron microscopic (EM) methods. Using EM tomography of high pressure frozen keratinocytes, we investigated the course of several filaments in a branching of a filament bundle. Moreover we found several putative bifurcations in individual filaments. To verify our observation we also visualized the keratin network in detergent extracted keratinocytes with scanning EM. Here bifurcations of individual filaments could unambiguously be identified additionally to bundle branchings. Interestingly, identical filament bifurcations were also found in purified keratin 8/18 filaments expressed in Escherichia coli which were reassembled in vitro. This excludes that an accessory protein contributes to the branch formation. Measurements of the filament cross sectional areas showed various ratios between the three bifurcation arms. This demonstrates that intermediate filament furcation is very different from actin furcation where an entire new filament is attached to an existing filament. Instead, the architecture of intermediate filament bifurcations is less predetermined and hence consistent with the general concept of IF formation. PMID:27039023

  20. Risk Factor Assessment Branch (RFAB)

    Science.gov (United States)

    The Risk Factor Assessment Branch (RFAB) focuses on the development, evaluation, and dissemination of high-quality risk factor metrics, methods, tools, technologies, and resources for use across the cancer research continuum, and the assessment of cancer-related risk factors in the population.

  1. NCI: DCTD: Biometric Research Branch

    Science.gov (United States)

    The Biometric Research Branch (BRB) is the statistical and biomathematical component of the Division of Cancer Treatment, Diagnosis and Centers (DCTDC). Its members provide statistical leadership for the national and international research programs of the division in developmental therapeutics, developmental diagnostics, diagnostic imaging and clinical trials.

  2. Fluid Flow at Branching Junctions

    OpenAIRE

    Sochi, Taha

    2013-01-01

    The flow of fluids at branching junctions plays important kinematic and dynamic roles in most biological and industrial flow systems. The present paper highlights some key issues related to the flow of fluids at these junctions with special emphasis on the biological flow networks particularly blood transportation vasculature.

  3. Integrability and the Conformal Field Theory of the Higgs branch

    CERN Document Server

    Sax, Olof Ohlsson; Stefanski, Bogdan

    2014-01-01

    In the context of the AdS$_3$/CFT$_2$ correspondence, we investigate the CFT$_2$ at the origin of the Higgs branch. This theory has a planar, weak-coupling limit, in which anomalous dimensions of single-trace composite operators can be calculated. At one loop, the calculation reduces to finding the spectrum of a spin-chain with nearest-neighbour interactions. This CFT$_2$ spin-chain matches precisely the one that was previously found as the weak-coupling limit of the integrable system describing the AdS$_3$ side of the duality. We compute the one-loop dilatation operator in a non-trivial compact subsector and show that it corresponds to an integrable spin-chain Hamiltonian. This provides the first direct evidence of integrability on the CFT$_2$ side of the correspondence.

  4. Catch Chain

    OpenAIRE

    Talbert, Robert

    2010-01-01

    Catch Chain is a book of poems that traces the journey of a Corrections Officer who attempts to combat issues of isolation, inhumane treatment of inmates and societal rejection in jails by embarking upon a cross-country road trip. However, the same issues the officer initially wrestled with begin cropping up in different cities, on various highways and in a multitude of states. The excitement and adventure of the open road runs parallel to the recurring imprisonment of the guard's mind.

  5. The Considere condition and rapid stretching of linear and branched polymer melts

    DEFF Research Database (Denmark)

    McKinley, Gareth H; Hassager, Ole

    1999-01-01

    to larger Hencky strains as the number of branches is increased. Numerical computations at finite Deborah numbers also show that there is an optimal range of deformation rates over which homogeneous extensions can be maintained to large strain. We also consider other rapid homogeneous stretching...... deformations, such as biaxial and planar stretching, and show that the degree of stabilization afforded by inclusion of material with long-chain branching is a sensitive function of the imposed mode of deformation....

  6. Linear chains and chain-like fractals from electrostatic heteroaggregation.

    Science.gov (United States)

    Kim, Anthony Y; Hauch, Kip D; Berg, John C; Martin, James E; Anderson, Robert A

    2003-04-01

    The internal structure of materials prepared by aggregation of oppositely charged polystyrene spheres (electrostatic heteroaggregation) is investigated by static light scattering, optical microscopy, and Brownian dynamics simulation. Light scattering indicates ultralow mass fractal dimensions, as low as 1.2. Such low fractal dimensions, approaching the theoretical limit of a linear object, imply a chaining mechanism. Optical micrographs reveal linear chains with the particle charge alternating down the chains. Brownian dynamics simulation gives additional support for a chaining mechanism. For the polystyrene system (120-nm primary particle diameters), the fractal dimension is found to increase from 1.2 to 1.7 as the background electrolyte is increased. In terms of electrostatic screening, the results match those reported recently for larger polystyrene spheres. The low fractal dimensions appear to represent a crossover from linear chains to a structure of diffusion-limited aggregates; however, experiments under density-neutral conditions imply that sedimentation plays an important role in the formation of ultralow fractal dimensions. The practical implication is that microcomposites with a locally uniform distribution of starting materials and almost any degree of branching can be prepared from oppositely charged particles. PMID:12742045

  7. Branching processes in disease epidemics

    Science.gov (United States)

    Singh, Sarabjeet

    Branching processes have served as a model for chemical reactions, biological growth processes and contagion (of disease, information or fads). Through this connection, these seemingly different physical processes share some common universalities that can be elucidated by analyzing the underlying branching process. In this thesis, we focus on branching processes as a model for infectious diseases spreading between individuals belonging to different populations. The distinction between populations can arise from species separation (as in the case of diseases which jump across species) or spatial separation (as in the case of disease spreading between farms, cities, urban centers, etc). A prominent example of the former is zoonoses -- infectious diseases that spill from animals to humans -- whose specific examples include Nipah virus, monkeypox, HIV and avian influenza. A prominent example of the latter is infectious diseases of animals such as foot and mouth disease and bovine tuberculosis that spread between farms or cattle herds. Another example of the latter is infectious diseases of humans such as H1N1 that spread from one city to another through migration of infectious hosts. This thesis consists of three main chapters, an introduction and an appendix. The introduction gives a brief history of mathematics in modeling the spread of infectious diseases along with a detailed description of the most commonly used disease model -- the Susceptible-Infectious-Recovered (SIR) model. The introduction also describes how the stochastic formulation of the model reduces to a branching process in the limit of large population which is analyzed in detail. The second chapter describes a two species model of zoonoses with coupled SIR processes and proceeds into the calculation of statistics pertinent to cross species infection using multitype branching processes. The third chapter describes an SIR process driven by a Poisson process of infection spillovers. This is posed as a

  8. Strategy formulation for a national branch of selected multinational IS/ICT company

    OpenAIRE

    Lukáčová, Dominika

    2015-01-01

    The topic of the bachelor thesis is "Strategy formulation for a national branch of select-ed multinational IS/ICT company". Its goal is an evaluation of the business environment of the chosen branch of the multinational enterprise AB&C, examination of the subsidiary's situation and formulation of a proper strategy for the branch based on its capabilities. The foundations for this analysis were PEST analysis, Porter five forces and value-chain analysis and SWOT analysis. The result of this the...

  9. BDC 500 branch driver controller

    CERN Document Server

    Dijksman, A

    1981-01-01

    This processor has been designed for very fast data acquisition and date pre-processing. The dataway and branch highway speeds have been optimized for approximately 1.5 mu sec. The internal processor cycle is approximately 0.8 mu sec. The standard version contains the following functions (slots): crate controller type A1; branch highway driver including terminator; serial I/O port (TTY, VDU); 24 bit ALU and 24 bit program counter; 16 bit memory address counter and 4 word stack; 4k bit memory for program and/or data; battery backup for the memory; CNAFD and crate LAM display; request/grant logic for time- sharing operation of several BDCs. The free slots can be equipped with e.g. extra RAM, computer interfaces, hardware multiplier/dividers, etc. (0 refs).

  10. Solid State Photovoltaic Research Branch

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This report summarizes the progress of the Solid State Photovoltaic Research Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30,l 1989. Six technical sections of the report cover these main areas of SERIs in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Laser Raman and Luminescence Spectroscopy. Sections have been indexed separately for inclusion on the data base.

  11. Creep of welded branched pipes

    OpenAIRE

    Rayner, Glen

    2004-01-01

    Creep failure of welds in high-temperature power plant steam piping systems is known to be a potential cause of plant failure. Creep behaviour of plain pipes with circumferential welds and cross-weld specimens have received fairly extensive attention. However, research into the creep behaviour of welded thick-walled branched steam pipes has received less attention. Consequently, this thesis addresses improving the understanding of the creep behaviour for this type of geometry. Numerical and a...

  12. Interactions between Axillary Branches of Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Veronica Ongaro; Katherine Bainbridge; Lisa Williamson; Ottoline Leyser

    2008-01-01

    Studies of apical dominance have benefited greatly from two-branch assays in pea and bean,in which the shoot system is trimmed back to leave only two active cotyledonary axillary branches.In these two-branch shoots,a large body of evidence shows that one actively growing branch is able to inhibit the growth of the other,prompting studies on the nature of the inhibitory signals,which are still poorly understood.Here,we describe the establishment of two-branch assays in Arabidopsis,using consecutive branches on the bolting stem.As with the classical studies in pea and bean,these consecutive branches are able to inhibit one another's growth.Not only can the upper branch inhibit the lower branch,but also the lower branch can inhibit the upper branch,illustrating the bi-directional action of the inhibitory signals.Using mutants,we show that the inhibition is partially dependent on the MAX pathway and that while the inhibition is clearly transmitted across the stem from the active to the inhibited branch,the vascular connectivity of the two branches is weak,and the MAX pathway is capable of acting unilaterally in the stem.

  13. Branching processes and neutral evolution

    CERN Document Server

    Taïb, Ziad

    1992-01-01

    The Galton-Watson branching process has its roots in the problem of extinction of family names which was given a precise formulation by F. Galton as problem 4001 in the Educational Times (17, 1873). In 1875, an attempt to solve this problem was made by H. W. Watson but as it turned out, his conclusion was incorrect. Half a century later, R. A. Fisher made use of the Galton-Watson process to determine the extinction probability of the progeny of a mutant gene. However, it was J. B. S. Haldane who finally gave the first sketch of the correct conclusion. J. B. S. Haldane also predicted that mathematical genetics might some day develop into a "respectable branch of applied mathematics" (quoted in M. Kimura & T. Ohta, Theoretical Aspects of Population Genetics. Princeton, 1971). Since the time of Fisher and Haldane, the two fields of branching processes and mathematical genetics have attained a high degree of sophistication but in different directions. This monograph is a first attempt to apply the current sta...

  14. Synthesis of Branched Chainswith Actuation Redundancy for Eliminating Interior Singularities of 3T1R Parallel Mechanisms

    Institute of Scientific and Technical Information of China (English)

    LI Shihua; LIU Yanmin; CUI Hongliu; NIU Yunzhan; andZHAO Yanzhi

    2016-01-01

    Although it is common to eliminate the singularity of parallel mechanism by adding the branched chain with actuation redundancy, there is no theory and method for the configuration synthesis of the branched chain with actuation redundancy in parallel mechanism. Branched chains with actuation redundancy are synthesized for eliminating interior singularity of 3-translational and 1- rotational(3T1R) parallel mechanisms. Guided by the discriminance method of hybrid screw group according to Grassmann line geometry, all the possibilities are listed for the occurrence of interior singularities in 3T1R parallel mechanism. Based on the linear relevance of screw system and the principles of eliminating parallel mechanism singularity with actuation redundancy, different types of branched chains with actuation redundancy are synthesized systematically to indicate the layout and the number of the branched chainsinterior with actuation redundancy. A general method is proposed for the configuration synthesis of the branched chains with actuation redundancy of the redundant parallel mechanism, and it builds a solid foundation for the subsequent performance optimization of the redundant actuation parallel mechanism.

  15. Characterization of the reactions of starch branching enzymes from rice endosperm.

    Science.gov (United States)

    Nakamura, Yasunori; Utsumi, Yoshinori; Sawada, Takayuki; Aihara, Satomi; Utsumi, Chikako; Yoshida, Mayumi; Kitamura, Shinichi

    2010-05-01

    To our knowledge the present paper shows for the first time the kinetic parameters of all the three starch branching enzyme (BE) isozymes, BEI, BEIIa and BEIIb, from rice with both amylopectin and synthetic amylose as glucan substrate. The activities of these BE isozymes with a linear glucan amylose decreased with a decrease in the molar size of amylose, and no activities of BEIIa and BEIIb were found when the degree of polymerization (DP) of amylose was lower than at least 80, whereas BEI had an activity with amylose of a DP higher than approximately 50. Detailed analyses of debranched products from BE reactions revealed the distinct chain length preferences of the individual BE isozymes. BEIIb almost exclusively transferred chains of DP7 and DP6 while BEIIa formed a wide range of short chains of DP6 to around DP15 from outer chains of amylopectin and amylose. On the other hand, BEI formed a variety of short chains and intermediate chains of a DP chains but also inner chains of branched glucan while BEIIa or BEIIb could only scarcely or could not attack inner chains, respectively. The comprehensive in vitro studies revealed different enzymatic characteristics of the three BE isozymes and give a new insight into the distinct roles of individual BE isozymes in amylopectin biosynthesis in the endosperm. Based on these results, the functional distinction and interaction of BE isozymes during amylopectin biosynthesis in cereal endosperm is discussed. PMID:20305271

  16. The Effect of Supplement with Branched -chain Amino Acid, Creatine on Blood Biochemical IndeX of Yili Horse%补喂支链氨基酸﹑肌酸对伊犁马血浆生化指标的影响

    Institute of Scientific and Technical Information of China (English)

    李晓斌; 马军; 聂彪彪; 杨景焘; 乔春江; 杨开伦

    2015-01-01

    Objective] This study aims to determine the effects of the branchedchain supplemented with amino acid (BCAA) and creatine (Cr) on the change of the plasma antioxidant index,hormone level,the concentration of creatine,glucose,lactic acid,uric acid and creatinine in plasma of the Yili horses,thus provi_ding reference data for effective nutritious additives in horse sports training fodder.[Method]12 well —trained male horses of 3 —5 years old (average 4 years old),weight 390 —514kg (average 457 ±50 kg) and the simi_lar performance were selected as the subjects in the experiments.They were divided into 3 groups with four in each and one group was fed with basal diet (the control group).The experimental group one was fed with diet supplemented with BCAA and the experimental group two was fed with diet supplemented with Cr.On the 0 day,1 d,14 d,21 d and 31 d jugular vein blood was collected after feeding 4 hours later,and testing kit was used to measure the related indexes.[Result]The total antioxidant capacity in plasma was increased by the di_et supplemented with creatine after feeding 4 h later,and the difference was significant compared with control group (P ﹤0.05).Especially on 14 d and 31 d it was increased by 21.79% and 25.68%; BCAA reduced MDA content during the test,No significant differences were observed in the concentrations of insulin,glucagon and cortisol hormones ,creatine,glucose,lactic acid,uric acid and creatinine of plasma compared with the con_trol group (P ﹥0.05).[Conclusion]The results indicated that the diet supplemented with BCAA could re_duce lipid peroxidation products MDA concentration; Fodder supplemented with Cr could improve SOD vigor and improve the Yili horse′s serum total antioxidant capacity,but no obvious effects were found in other inde_xes.%【目的】研究补喂支链氨基酸(BCAA)﹑肌酸(Cr)对伊犁马血浆抗氧化指标﹑激素水平﹑肌酸﹑葡萄糖浓度以及乳酸﹑尿酸和肌酐含量的影

  17. The Effects of a Branch Campus

    Science.gov (United States)

    Lien, Donald; Wang, Yaqin

    2012-01-01

    We examine the effects of a branch campus on the social welfare of the host country and the foreign university. Overall, we find that a branch campus increases both the domestic social welfare (measured by the aggregate student utility) and the tuition revenue of the foreign university. The effect of a branch campus on the brain drain is…

  18. Stochastic Transition between Turbulent Branch and Thermodynamic Branch of an Inhomogeneous Plasma

    OpenAIRE

    Kawasaki, Mitsuhiro; Itoh, Sanae-I.; Yagi, Masatoshi; Itoh, Kimitaka

    2002-01-01

    Transition phenomena between thermodynamic branch and turbulent branch in submarginal turbulent plasma are analyzed with statistical theory. Time-development of turbulent fluctuation is obtained by numerical simulations of Langevin equation which contains submarginal characteristics. Probability density functions and transition rates between two states are analyzed. Transition from turbulent branch to thermodynamic branch occurs in almost entire region between subcritical bifurcation point an...

  19. Branch Point Withdrawal in Elongational Startup Flow by Time-Resolved Small Angle Neutron Scattering

    KAUST Repository

    Ruocco, N.

    2016-05-27

    We present a small angle neutron scattering (SANS) investigation of a blend composed of a dendritic polymer and a linear matrix with comparable viscosity in start-up of an elongational flow at Tg + 50. The two-generation dendritic polymer is diluted to 10% by weight in a matrix of a long well-entangled linear chains. Both components consist of mainly 1,4-cis-polyisoprene but differ in isotopic composition. The resulting scattering contrast is sufficiently high to permit time-resolved measurements of the system structure factor during the start-up phase and to follow the retraction processes involving the inner sections of the branched polymer in the nonlinear deformation response. The outer branches and the linear matrix, on the contrary, are in the linear deformation regime. The linear matrix dominates the rheological signature of the blend and the influence of the branched component can barely be detected. However, the neutron scattering intensity is predominantly that of the (branched) minority component so that its dynamics is clearly evident. In the present paper, we use the neutron scattering data to validate the branch point withdrawal process, which could not be unambiguously discerned from rheological measurements in this blend. The maximal tube stretch that the inner branches experience, before the relaxed outer arm material is incorporated into the tube is determined. The in situ scattering experiments demonstrate for the first time the leveling-off of the strain as the result of branch point withdrawal and chain retraction directly on the molecular level. We conclude that branch point motion in the mixture of architecturally complex polymers occurs earlier than would be expected in a purely branched system, presumably due to the different topological environment that the linear matrix presents to the hierarchically deep-buried tube sections. © 2016 American Chemical Society.

  20. Chain reaction

    International Nuclear Information System (INIS)

    Chain Reaction is a work of recent American political history. It seeks to explain how and why America came to depend so heavily on its experts after World War II, how those experts translated that authority into political clout, and why that authority and political discretion declined in the 1970s. The author's research into the internal memoranda of the Atomic Energy Commission substantiates his argument in historical detail. It was not the ravages of American anti-intellectualism, as so many scholars have argued, that brought the experts back down to earth. Rather, their decline can be traced to the very roots of their success after World War II. The need to over-state anticipated results in order to garner public support, incessant professional and bureaucratic specialization, and the sheer proliferation of expertise pushed arcane and insulated debates between experts into public forums at the same time that a broad cross section of political participants found it easier to gain access to their own expertise. These tendencies ultimately undermined the political influence of all experts. (author)

  1. Chemical modifications of Sterculia foetida L. oil to branched ester derivatives

    NARCIS (Netherlands)

    Manurung, Robert; Daniel, Louis; van de Bovenkamp, Hendrik H.; Buntara, Teddy; Maemunah, Siti; Kraai, Gerard; Makertihartha, I. G. B. N.; Broekhuis, Antonius A.; Heeres, Hero J.

    2012-01-01

    An experimental study to modify Sterculia foetida L. oil (STO) or the corresponding methyl esters (STO FAME) to branched ester derivatives is reported. The transformations involve conversion of the cyclopropene rings in the fatty acid chains of STO through various catalytic as well as stoichiometric

  2. Synthesis and properties of highly branched Jatropha curcas L. oil derivatives

    NARCIS (Netherlands)

    Daniel, Louis; Ardiyanti, Agnes R.; Schuur, Boelo; Manurung, Robert; Broekhuis, Antonius A.; Heeres, Hero J.

    2011-01-01

    The synthesis and properties of a number of novel branched Jatropha curcas L. oil (JO) derivatives containing vicinal di-ester units in the fatty acid chains are reported. Both the length (acetyl vs. hexanoyl) and the stereochemistry of the vicinal di-ester units (cis vs. trans) were varied. The com

  3. Creep measurements confirm steady flow after stress maximum in extension of branched polymer melts

    DEFF Research Database (Denmark)

    Javier Alvarez, Nicolas; Román Marín, José Manuel; Huang, Qian;

    2013-01-01

    We provide conclusive evidence of nonmonotonic mechanical behavior in the extension of long-chain branched polymer melts. While nonmonotonic behavior is known to occur for solids, for the case of polymeric melts, this phenomenon is in direct contrast with current theoretical models. We rule out t...

  4. 谷氨酰胺、EPA、支链氨基酸对食管癌同步放化疗及胃癌术后辅助化疗患者的影响%Impact of glutamine, eicosapntemacnioc acid, branched-chain amino acid supplements on nutritional status and treatment compliance of esophageal cancer patients on concurrent chemoradiotherapy and gastric cancer patients on chemotherapy

    Institute of Scientific and Technical Information of China (English)

    丛明华; 宋晨鑫; 邹宝华; 邓颖冰; 李淑娈; 刘雪辉; 刘微微; 刘金英; 于雷

    2015-01-01

    Objective To explore the effects of glutamine,eicosapntemacnioc acid (EPA) and branched-chain amino acids supplements in esophageal cancer patients on concurrent chemoradiotherapy and gastric cancer patients on chemotherapy.Methods From April 2013 to April 2014,a total of 104 esophageal and gastric carcinoma patients on chemotherapy or concurrent chemoradiotherapy were recruited and randomly divided into experimental and control groups.Both groups received dietary counseling and routine nutritional supports while only experimental group received supplements of glutamine (20 g/d),EPA (3.3 g/d) and branched-chain amino acids (8 g/d).And body compositions,blood indicators,incidence of complications and completion rates of therapy were compared between two groups.Results After treatment,free fat mass and muscle weight increased significantly in experiment group while decreased in control group (P < 0.05).And albumin,red blood cell count,white blood cell count and blood platelet count remained stable in experiment group while declined significantly in control group.During treatment,compared to control group,the incidences of infection-associated complication were lower (6% vs 19%,P < 0.05) and the completion rates of therapy were significantly higher in experiment group (96% vs 83%,P < 0.05).Conclusion Supplements of glutamine,EPA and branched-chain amino acids can help maintain nutrition status,decrease the complications and improve compliance for esophageal cancer patients on concurrent chemo-radiotherapy and gastric cancer patients on postoperative adjuvant chemotherapy.%目的 观察补充谷氨酰胺、二十碳五烯酸(EPA)、支链氨基酸对食管癌同步放化疗及胃癌术后辅助化疗患者的作用.方法 2013年4月至2014年4月因食管癌、胃癌在中国医学科学院肿瘤医院和北京桓兴病区拟行化疗或同步化放疗患者104例入组,数字随机分为试验组和对照组进行营养干预,两组均进行

  5. Branching diffusions in random environment

    CERN Document Server

    Böinghoff, Christian

    2011-01-01

    We consider the diffusion approximation of branching processes in random environment (BPREs). This diffusion approximation is similar to and mathematically more tractable than BPREs. We obtain the exact asymptotic behavior of the survival probability. As in the case of BPREs, there is a phase transition in the subcritical regime due to different survival opportunities. In addition, we characterize the process conditioned to never go extinct and establish a backbone construction. In the strongly subcritical regime, mean offspring numbers are increased but still subcritical in the process conditioned to never go extinct. Here survival is solely due to an immortal individual, whose offspring are the ancestors of additional families. In the weakly subcritical regime, the mean offspring number is supercritical in the process conditioned to never go extinct. Thus this process survives with positive probability even if there was no immortal individual.

  6. Recursive Branching Simulated Annealing Algorithm

    Science.gov (United States)

    Bolcar, Matthew; Smith, J. Scott; Aronstein, David

    2012-01-01

    This innovation is a variation of a simulated-annealing optimization algorithm that uses a recursive-branching structure to parallelize the search of a parameter space for the globally optimal solution to an objective. The algorithm has been demonstrated to be more effective at searching a parameter space than traditional simulated-annealing methods for a particular problem of interest, and it can readily be applied to a wide variety of optimization problems, including those with a parameter space having both discrete-value parameters (combinatorial) and continuous-variable parameters. It can take the place of a conventional simulated- annealing, Monte-Carlo, or random- walk algorithm. In a conventional simulated-annealing (SA) algorithm, a starting configuration is randomly selected within the parameter space. The algorithm randomly selects another configuration from the parameter space and evaluates the objective function for that configuration. If the objective function value is better than the previous value, the new configuration is adopted as the new point of interest in the parameter space. If the objective function value is worse than the previous value, the new configuration may be adopted, with a probability determined by a temperature parameter, used in analogy to annealing in metals. As the optimization continues, the region of the parameter space from which new configurations can be selected shrinks, and in conjunction with lowering the annealing temperature (and thus lowering the probability for adopting configurations in parameter space with worse objective functions), the algorithm can converge on the globally optimal configuration. The Recursive Branching Simulated Annealing (RBSA) algorithm shares some features with the SA algorithm, notably including the basic principles that a starting configuration is randomly selected from within the parameter space, the algorithm tests other configurations with the goal of finding the globally optimal

  7. Branching process models of cancer

    CERN Document Server

    Durrett, Richard

    2015-01-01

    This volume develops results on continuous time branching processes and applies them to study rate of tumor growth, extending classic work on the Luria-Delbruck distribution. As a consequence, the authors calculate the probability that mutations that confer resistance to treatment are present at detection and quantify the extent of tumor heterogeneity. As applications, the authors evaluate ovarian cancer screening strategies and give rigorous proofs for results of Heano and Michor concerning tumor metastasis. These notes should be accessible to students who are familiar with Poisson processes and continuous time. Richard Durrett is mathematics professor at Duke University, USA. He is the author of 8 books, over 200 journal articles, and has supervised more than 40 Ph.D. students. Most of his current research concerns the applications of probability to biology: ecology, genetics, and most recently cancer.

  8. Vegetation survey of PEN Branch wetlands

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

  9. 3D modelling of branching in plants

    OpenAIRE

    Evers, J.B.

    2011-01-01

    Shoot branching is a key determinant of overall aboveground plant form. During plant development, the number of branches formed strongly influences the amount of light absorbed by the plant, and thus the plant’s competitive strength in terms of light capture in relation to neighbouring plants. Branching is regulated by multiple internal factors which are modulated by different environmental signals. A key environmental signal in the context of a plant population is a low red / far-red intensi...

  10. Supercritical branching diffusions in random environment

    CERN Document Server

    Hutzenthaler, Martin

    2011-01-01

    Supercritical branching processes in constant environment conditioned on eventual extinction are known to be subcritical branching processes. The case of random environment is more subtle. A supercritical branching diffusion in random environment (BDRE) conditioned on eventual extinction of the population is not a BDRE. However the quenched law of the population size of a supercritical BDRE conditioned on eventual extinction is equal to the quenched law of the population size of a subcritical BDRE. As a consequence, supercritical BDREs have a phase transition which is similar to a well-known phase transition of subcritical branching processes in random environment.

  11. Current perspectives on shoot branching regulation

    Directory of Open Access Journals (Sweden)

    Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO

    2015-03-01

    Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

  12. Clinical and Translational Epidemiology Branch (CTEB)

    Science.gov (United States)

    The Clinical and Translational Epidemiology Branch focuses on factors that influence cancer progression, recurrence, survival, and other treatment outcomes, and factors associated with cancer development.

  13. Networks of companies and branches in Poland

    CERN Document Server

    Chmiel, A M; Sienkiewicz, J; Suchecki, K; Chmiel, Anna M.; Holyst, Janusz A.; Sienkiewicz, Julian; Suchecki, Krzysztof

    2006-01-01

    In this study we consider relations between companies in Poland taking into account common branches they belong to. It is clear that companies belonging to the same branch compete for similar customers, so the market induces correlations between them. On the other hand two branches can be related by companies acting in both of them. To remove weak, accidental links we shall use a concept of threshold filtering for weighted networks where a link weight corresponds to a number of existing connections (common companies or branches) between a pair of nodes.

  14. Branch mode selection during early lung development.

    Directory of Open Access Journals (Sweden)

    Denis Menshykau

    Full Text Available Many organs of higher organisms, such as the vascular system, lung, kidney, pancreas, liver and glands, are heavily branched structures. The branching process during lung development has been studied in great detail and is remarkably stereotyped. The branched tree is generated by the sequential, non-random use of three geometrically simple modes of branching (domain branching, planar and orthogonal bifurcation. While many regulatory components and local interactions have been defined an integrated understanding of the regulatory network that controls the branching process is lacking. We have developed a deterministic, spatio-temporal differential-equation based model of the core signaling network that governs lung branching morphogenesis. The model focuses on the two key signaling factors that have been identified in experiments, fibroblast growth factor (FGF10 and sonic hedgehog (SHH as well as the SHH receptor patched (Ptc. We show that the reported biochemical interactions give rise to a Schnakenberg-type Turing patterning mechanisms that allows us to reproduce experimental observations in wildtype and mutant mice. The kinetic parameters as well as the domain shape are based on experimental data where available. The developed model is robust to small absolute and large relative changes in the parameter values. At the same time there is a strong regulatory potential in that the switching between branching modes can be achieved by targeted changes in the parameter values. We note that the sequence of different branching events may also be the result of different growth speeds: fast growth triggers lateral branching while slow growth favours bifurcations in our model. We conclude that the FGF10-SHH-Ptc1 module is sufficient to generate pattern that correspond to the observed branching modes.

  15. Branch mode selection during early lung development.

    Science.gov (United States)

    Menshykau, Denis; Kraemer, Conradin; Iber, Dagmar

    2012-01-01

    Many organs of higher organisms, such as the vascular system, lung, kidney, pancreas, liver and glands, are heavily branched structures. The branching process during lung development has been studied in great detail and is remarkably stereotyped. The branched tree is generated by the sequential, non-random use of three geometrically simple modes of branching (domain branching, planar and orthogonal bifurcation). While many regulatory components and local interactions have been defined an integrated understanding of the regulatory network that controls the branching process is lacking. We have developed a deterministic, spatio-temporal differential-equation based model of the core signaling network that governs lung branching morphogenesis. The model focuses on the two key signaling factors that have been identified in experiments, fibroblast growth factor (FGF10) and sonic hedgehog (SHH) as well as the SHH receptor patched (Ptc). We show that the reported biochemical interactions give rise to a Schnakenberg-type Turing patterning mechanisms that allows us to reproduce experimental observations in wildtype and mutant mice. The kinetic parameters as well as the domain shape are based on experimental data where available. The developed model is robust to small absolute and large relative changes in the parameter values. At the same time there is a strong regulatory potential in that the switching between branching modes can be achieved by targeted changes in the parameter values. We note that the sequence of different branching events may also be the result of different growth speeds: fast growth triggers lateral branching while slow growth favours bifurcations in our model. We conclude that the FGF10-SHH-Ptc1 module is sufficient to generate pattern that correspond to the observed branching modes. PMID:22359491

  16. ECONOMIC ISSUES OF BRANCH PRODUCTION

    Directory of Open Access Journals (Sweden)

    Shamrov K. N.

    2015-05-01

    Full Text Available The article deals with topical questions of economy industry production of rice grain. The need for improving the business efficiency of rice today is dictated by political and economic sanctions, the needs of our society in full substitution of this important product. State stimulation of rice development today is carried out through a complex of economic and administrative activities. The economic measures of the state include: price control on rice price and processing products, support of agricultural producers’ incomes, leasing involving the state, marketing of products, and infrastructure development of the grain market. The system of public administrative measures also includes standardization and certification of grain products, control quality of grain and products of its processing, the quarantine protection, licensing activities organizations, and mandatory statistical account of the rice market. These measures are intended to ensure equal conditions of competition between local and imported rice, to spur investment and expansion of domestic production, increase profitability of rice, allowing the rice enterprises to carry out expensive irrigation systems repairs and capital inputs in lot lend. The article suggests that rice branch industry remains competitive and with abolition of import customs barriers within frameworks WTO. It is necessary to invest more heavily in infrastructure with the aim of improving business efficiency of rice

  17. 12 CFR 741.11 - Foreign branching.

    Science.gov (United States)

    2010-01-01

    ...) Contents of Business Plan. The written business plan must address the following: (1) Analysis of market... regarding the branch (shares, lending, capital, charge-offs, collections); (6) The field of membership or... for branch operations (balance sheet and income and expense projections) for the first and second...

  18. Branching out Has So Much to Offer

    Science.gov (United States)

    Murray, Joe

    2012-01-01

    In 1989 there were thirty ATM branches nationally. In January 2012 there were just twelve ATM branches with another three "proposed". How can that happen? How did it happen? Maybe the most pertinent question is: Why did it happen? There is no single answer to the last question, but perhaps it was something to do with the changes that were sweeping…

  19. Silicone chain extender

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a silicone chain extender, more particularly a chain extender for silicone polymers and copolymers, to a chain extended silicone polymer or copolymer and to a functionalized chain extended silicone polymer or copolymer, to a method for the preparation thereof and...

  20. Health supply chain management.

    Science.gov (United States)

    Zimmerman, Rolf; Gallagher, Pat

    2010-01-01

    This chapter gives an educational overview of: * The actual application of supply chain practice and disciplines required for service delivery improvement within the current health environment. * A rationale for the application of Supply Chain Management (SCM) approaches to the Health sector. * The tools and methods available for supply chain analysis and benchmarking. * Key supply chain success factors. PMID:20407173

  1. [Croatian Medical Association--Branch Zagreb].

    Science.gov (United States)

    Kaić, Zvonimir; Sain, Snjezana; Gulić, Mirjana; Mahovlić, Vjekoslav; Krznarić, Zeljko

    2014-01-01

    The available literature shows us that "Druztvo ljeciteljah u Zagrebus (the Society of Healers in Zagreb) was founded as far back as the year 1845 by a total of thirteen members. This data allows us to follow the role of doctors and health workers in Zagreb through their everyday profession, research, organizational and social work as well as management through a period of over one hundred to seventy years. The Branch Zagreb was active before the official establishment of subsidiaries of CMA which is evident from the minutes of the regular annual assembly of the Croatian Medical Association on 21 March 1948. Until the end of 1956, there was no clear division of labor, functions and competencies between the Branch and the Main Board. Their actions were instead consolidated and the Branch operated within and under the name of Croatian Medical Association. In that year the Branch became independent. The Branch Zagreb is the largest and one of the most active branches of the Croatian Medical Association. At the moment, the Branch brings together 3621 members, regular members--doctors of medicine (2497), doctors of dental medicine (384), retired physicians (710), and associate members (30 specialists with higher education who are not doctors). The Branch is especially accomplished in its activities in the area of professional development of its members and therefore organizes a series of scientific conferences in the framework of continuous education of physicians, allowing its members to acquire necessary points for the extension of their operating license. The choir "Zagrebacki lijecnici pjevaci" (Zagreb Physicians' Choir) of the Croatian Medical Music Society of the CMA and its activities are inseparable from the Branch Zagreb. The Branch is firmly linked to the parent body, the CMA, and thus has a visible impact on the strategy and the activities of the Association as a whole. Most professional societies of the CMA have their headquarters in Zagreb and this is

  2. Automated generation of burnup chain for reactor analysis applications

    International Nuclear Information System (INIS)

    This paper presents the development of an automated generation of a new burnup chain for reactor analysis applications. The JENDL FP Decay Data File 2011 and Fission Yields Data File 2011 were used as the data sources. The nuclides in the new chain are determined by restrictions of the half-life and cumulative yield of fission products or from a given list. Then, decay modes, branching ratios and fission yields are recalculated taking into account intermediate reactions. The new burnup chain is output according to the format for the SRAC code system. Verification was performed to evaluate the accuracy of the new burnup chain. The results show that the new burnup chain reproduces well the results of a reference one with 193 fission products used in SRAC. Further development and applications are being planned with the burnup chain code. (author)

  3. Branch architecture, light interception and crown development in saplings of a plagiotropically branching tropical tree, Polyalthia jenkinsii (Annonaceae).

    Science.gov (United States)

    Osada, Noriyuki; Takeda, Hiroshi

    2003-01-01

    To investigate crown development patterns, branch architecture, branch-level light interception, and leaf and branch dynamics were studied in saplings of a plagiotropically branching tree species, Polyalthia jenkinsii Hk. f. & Thoms. (Annonaceae) in a Malaysian rain forest. Lengths of branches and parts of the branches lacking leaves ('bare' branches) were smaller in upper branches than in lower branches within crowns, whereas lengths of 'leafy' parts and the number of leaves per branch were larger in intermediate than in upper and lower branches. Maximum diffuse light absorption (DLA) of individual leaves was not related to sapling height or branch position within crowns, whereas minimum DLA was lower in tall saplings. Accordingly, branch-level light interception was higher in intermediate than in upper and lower branches. The leaf production rate was higher and leaf loss rate was smaller in upper than in intermediate and lower branches. Moreover, the branch production rate of new first-order branches was larger in the upper crowns. Thus, leaf and branch dynamics do not correspond to branch-level light interception in the different canopy zones. As a result of architectural constraints, branches at different vertical positions experience predictable light microenvironments in plagiotropic species. Accordingly, this pattern of carbon allocation among branches might be particularly important for growth and crown development in plagiotropic species. PMID:12495920

  4. Measurement of Prominent eta Decay Branching Fractions

    CERN Document Server

    López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Sanghi, B; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Menaa, N; Mountain, R; Nisar, S; Randrianarivony, K; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Asner, D M; Edwards, K W; Naik, P; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A G; Ernst, J; Ecklund, K M; Severini, H; Love, W; Savinov, V

    2007-01-01

    The decay psi(2S) --> eta J/psi is used to measure, for the first time, all prominent eta-meson branching fractions with the same experiment in the same dataset, thereby providing a consistent treatment of systematics across branching fractions. We present results for eta decays to gamma gamma, pi+pi-pi0, 3 pi0, pi+ pi- gamma, and e+ e- gamma, accounting for 99.9% of all eta decays. The precisions for several of the branching fractions and their ratios are improved. Two channels, pi+ pi- gamma and e+ e- gamma, show results that differ at the level of three standard deviations from those previously determined.

  5. Cellular and physical mechanisms of branching morphogenesis

    Science.gov (United States)

    Varner, Victor D.; Nelson, Celeste M.

    2014-01-01

    Branching morphogenesis is the developmental program that builds the ramified epithelial trees of various organs, including the airways of the lung, the collecting ducts of the kidney, and the ducts of the mammary and salivary glands. Even though the final geometries of epithelial trees are distinct, the molecular signaling pathways that control branching morphogenesis appear to be conserved across organs and species. However, despite this molecular homology, recent advances in cell lineage analysis and real-time imaging have uncovered surprising differences in the mechanisms that build these diverse tissues. Here, we review these studies and discuss the cellular and physical mechanisms that can contribute to branching morphogenesis. PMID:25005470

  6. Agents in branching space-times

    Institute of Scientific and Technical Information of China (English)

    Nuel; Belnap

    2003-01-01

    The aim of this essay Is to make some brief suggestions on the beginnings of a theory of agentsand agency In branching spacetlmes.foe thought Is to combine the ideas of agency as developed agalnst the relatively simple background of branching time with the richer notions of Indetermlnlsm asstructured In the theory of branching space-times.My plan Is to say a little about agency In branchingtime and a little about branchlg spacetlmes,and then ask how the two can be brought together.Atthe end there Is an ...

  7. Arkansas State University Beebe Branch Faculty Handbook.

    Science.gov (United States)

    Arkansas State Univ., Beebe.

    Arkansas State University Beebe Branch provides a liberal arts oriented program for traditional and nontraditional students. Its faculty handbook contains institutional goals, description of responsibilities of administrative officers and faculty committees, faculty employment policies, and administrative and instructional policies. The…

  8. Damping by branching: a bioinspiration from trees

    CERN Document Server

    Theckes, Benoit; Boutillon, Xavier

    2011-01-01

    Man-made slender structures are known to be sensitive to high levels of vibration, due to their flexibility, which often cause irreversible damage. In nature, trees repeatedly endure large amplitudes of motion, mostly caused by strong climatic events, yet with minor or no damage in most cases. A new damping mechanism inspired by the architecture of trees is here identified and characterized in the simplest tree-like structure, a Y-shape branched structure. Through analytical and numerical analyses of a simple two-degree-of-freedom model, branching is shown to be the key ingredient in this protective mechanism that we call damping-by-branching. It originates in the geometrical nonlinearities so that it is specifically efficient to damp out large amplitudes of motion. A more realistic model, using flexible beam approximation, shows that the mechanism is robust. Finally, two bioinspired architectures are analyzed, showing significant levels of damping achieved via branching with typically 30% of the energy being...

  9. Code 672 observational science branch computer networks

    Science.gov (United States)

    Hancock, D. W.; Shirk, H. G.

    1988-01-01

    In general, networking increases productivity due to the speed of transmission, easy access to remote computers, ability to share files, and increased availability of peripherals. Two different networks within the Observational Science Branch are described in detail.

  10. FY 1990 Applied Sciences Branch annual report

    Energy Technology Data Exchange (ETDEWEB)

    Keyes, B.M.; Dippo, P.C. [eds.

    1991-11-01

    The Applied Sciences Branch actively supports the advancement of DOE/SERI goals for the development and implementation of the solar photovoltaic technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility which is capable of providing information on the full range of photovoltaic components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of photovoltaic technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. This report contains information on surface and interface analysis, materials characterization, development, electro-optical characterization module testing and performance, surface interactions and FTIR spectroscopy.

  11. Residence times of branching diffusion processes

    Science.gov (United States)

    Dumonteil, E.; Mazzolo, A.

    2016-07-01

    The residence time of a branching Brownian process is the amount of time that the mother particle and all its descendants spend inside a domain. Using the Feynman-Kac formalism, we derive the residence-time equation as well as the equations for its moments for a branching diffusion process with an arbitrary number of descendants. This general approach is illustrated with simple examples in free space and in confined geometries where explicit formulas for the moments are obtained within the long time limit. In particular, we study in detail the influence of the branching mechanism on those moments. The present approach can also be applied to investigate other additive functionals of branching Brownian process.

  12. Parton Branching in Color Mutation Model

    CERN Document Server

    Hwa, R C

    1999-01-01

    The soft production problem in hadronic collisions as described in the eikonal color mutation branching model is improved in the way that the initial parton distribution is treated. Furry branching of the partons is considered as a means of describing the nonperturbative process of parton reproduction in soft interaction. The values of all the moments, and $C_q$, for q=2,...,5, as well as their energy dependences can be correctly determined by the use of only two parameters.

  13. CAST Xi'an Branch Established

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ China Academy of Space Technology (CAST) Xi'an Branch was established on April 8,2008.The new branch consists of the headquarters of the former Xi'an Institute of Space Radio Technology (XISRT) of CAST and five former subsidiaries of the XISRT,i.e.the Institute of Space Electronic Technology,the Institute of Microwave Technology,the Institute of Space Antenna Technology,the Manufacturing Center for Space Electronics and Civilian High-tech Company.

  14. Comparative efficiency analysis of Portuguese bank branches

    OpenAIRE

    Portela, Maria; Thanassoulis, Emmanuel

    2006-01-01

    The advent of Internet banking and phone banking is changing the role of bank branches from a predominantly transaction- based one to a sales-oriented role. This paper reports on an assessment of the branches of a Portuguese bank in terms of their performance in their new roles in three different areas: Their efficiency in fostering the use of new transaction channels, their efficiency in increasing sales and their customer base, and their efficiency in generating profits. Service qu...

  15. Comparative performance analysis of portuguese bank branches

    OpenAIRE

    Portela, Maria; Thanassoulis, Emmanuel

    2003-01-01

    The advent of Internet banking and phone banking is changing the role of bank branches from a predominantly transaction-based one to a sales-oriented role. This paper reports on an assessment of the branches of a Portuguese bank in terms of their performance in their new roles in three different areas: Their effectiveness in fostering the use of new transaction channels such as the internet and the telephone, their effectiveness in increasing sales and their customer base, and the...

  16. AGB [asymptotic giant branch]: Star evolution

    International Nuclear Information System (INIS)

    Asymptotic giant branch stars are red supergiant stars of low-to-intermediate mass. This class of stars is of particular interest because many of these stars can have nuclear processed material brought up repeatedly from the deep interior to the surface where it can be observed. A review of recent theoretical and observational work on stars undergoing the asymptotic giant branch phase is presented. 41 refs

  17. Branch retinal artery occlusion in Susac's syndrome

    Directory of Open Access Journals (Sweden)

    Ricardo Evangelista Marrocos de Aragão

    2015-02-01

    Full Text Available Susac's syndrome is a rare disease attribuited to a microangiopathy involving the arterioles of the cochlea, retina and brain. Encefalopathy, hearing loss, and visual deficits are the hallmarks of the disease. Visual loss is due to multiple, recurrent branch arterial retinal occlusions. We report a case of a 20-year-old women with Susac syndrome presented with peripheral vestibular syndrome, hearing loss, ataxia, vertigo, and vision loss due occlusion of the retinal branch artery.

  18. Hyperbranched polymer stars with Gaussian chain statistics revisited.

    Science.gov (United States)

    Polińska, P; Gillig, C; Wittmer, J P; Baschnagel, J

    2014-02-01

    Conformational properties of regular dendrimers and more general hyperbranched polymer stars with Gaussian statistics for the spacer chains between branching points are revisited numerically. We investigate the scaling for asymptotically long chains especially for fractal dimensions df = 3 (marginally compact) and df = 2.5 (diffusion limited aggregation). Power-law stars obtained by imposing the number of additional arms per generation are compared to truly self-similar stars. We discuss effects of weak excluded-volume interactions and sketch the regime where the Gaussian approximation should hold in dense solutions and melts for sufficiently large spacer chains. PMID:24574057

  19. All change at the CERN UBS branch

    CERN Multimedia

    Antonella Del Rosso

    2012-01-01

    UBS branches across the country are being modernised, and the CERN branch is no exception. The Bulletin brings you a preview of the project, which will get under way in January 2013.   Mock-up of the renovated UBS branch. The changes at the UBS branch in CERN's Main Building will be no simple facelift. The entire bank will be renovated, transforming the present relatively confined premises into an open and attractive area. "The renovation of the UBS branches is part of a wider campaign designed to further enhance our customer relations," explains Ezio Mangia, the head of the CERN branch.  The UBS bank currently occupies three sets of premises in CERN's Main Building (two on the ground floor and one in the basement). "By the end of the work, which is scheduled to be completed by the middle of next year, CERN customers will benefit from a new area with open-plan counters and "hole-in-the-wall" machines accessible to...

  20. Characterization of linear and branched polyacrylates by tandem mass spectrometry.

    Science.gov (United States)

    Chaicharoen, Kittisak; Polce, Michael J; Singh, Anirudha; Pugh, Coleen; Wesdemiotis, Chrys

    2008-10-01

    The unimolecular degradation of alkali-metal cationized polyacrylates with the repeat unit CH(2)CH(COOR) and a variety of ester pendants has been examined by tandem mass spectrometry. The fragmentation patterns resulting from collisionally activated dissociation depend sensitively on the size of the ester alkyl substituent (R). With small alkyl groups, as in poly(methyl acrylate), lithiated or sodiated oligomers (M) decompose via free-radical chemistry, initiated by random homolytic C-C bond cleavages along the polymer chain. The radical ions formed this way dissociate further by backbiting rearrangements and beta scissions to yield a distribution of terminal fragments with one of the original end groups and internal fragments with 2-3 repeat units. If the ester alkyl group bears three or more carbon atoms, cleavages within the ester moieties become the predominant decomposition channel. This distinct reactivity is observed if R = t-butyl, n-butyl, or the mesogenic group (CH(2))(11)-O-C(6)H(4)-C(6)H(4)-CN. The [M+alkali metal](+) ions of the latter polyacrylates dissociate largely by charge-remote 1,5-H rearrangements that convert COOR to COOH groups by expulsion of 1-alkenes. The acid groups may displace an alcohol unit from a neighboring ester pendant to form a cyclic anhydride, unless hindered by steric effects. Using atom transfer radical polymerization, hyperbranched polyacrylates were prepared carrying ester groups both within and between the branches. Unique alkenes and alcohols are cleaved from ester groups at the branching points, enabling determination of the branching architecture. PMID:18373231

  1. Lyapunov Exponents for Branching Processes in a Random Environment: The Effect of Information

    Science.gov (United States)

    Hautphenne, Sophie; Latouche, Guy

    2016-04-01

    We consider multitype branching processes evolving in a Markovian random environment. To determine whether or not the branching process becomes extinct almost surely is akin to computing the maximal Lyapunov exponent of a sequence of random matrices, which is a notoriously difficult problem. We define Markov chains associated to the branching process, and we construct bounds for the Lyapunov exponent. The bounds are obtained by adding or by removing information: to add information results in a lower bound, to remove information results in an upper bound, and we show that adding less information improves the lower bound. We give a few illustrative examples and we observe that the upper bound is generally more accurate than the lower bounds.

  2. STUDIES ON REGULARITY OF POLY PHENYLSILSESQUIOXANE CHAINS

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xinsheng; CHEN Suming; SHI Lianghe

    1987-01-01

    IR and 29Si NMR were used to determine the structures of ladderlike polymer polyphenylsilsesquioxanes (PPS). It was found that PPS with lots of defects had a wide and strong absorption band in 1000-1400 cm- 1 with only one sharp peak at 1137 cm- 1 while two peaks (1130 and 1045 cm- 1) were observed for PPS with perfect ladderlike structure. Branching and crosslinking of PPS lead to the reduction of 1045cm- 1 peak. 29Si NMR spectra, however, showed two peaks (δ = -78 ppm and -87 ppm when δHMDs = 0 ppm) for defective or branched PPS. The -87 ppm peak is related to the ladderlikely constructed Si atoms and -78 ppm corresponds to defective Si atoms. PPS with defects less than 0.1% chain units was obtained by azeotropic polycondensations.

  3. Modification of potato starch composition by introduction and expression of bacterial branching enzyme genes.

    OpenAIRE

    Kortstee, A.J.

    1997-01-01

    Starch consists of two major components; amylose and amylopectin. Amylose is synthesized by the enzyme Granule-Bound Starch Syntase (GBSS) and consists of essentially linear chains of α-1,4 linked glucose residues. Amylopectin is synthesized by the combined activity of the enzymes Soluble Starch Synthase (SSS) and Branching enzyme (BE) and consists of linear α-1,4 linked glucosidic chains with α-1,6 linked branchpoints. The amount and fine structure of each of the components determine the sta...

  4. Efficient Transition Probability Computation for Continuous-Time Branching Processes via Compressed Sensing

    OpenAIRE

    Xu, Jason; Minin, Vladimir N.

    2015-01-01

    Branching processes are a class of continuous-time Markov chains (CTMCs) with ubiquitous applications. A general difficulty in statistical inference under partially observed CTMC models arises in computing transition probabilities when the discrete state space is large or uncountable. Classical methods such as matrix exponentiation are infeasible for large or countably infinite state spaces, and sampling-based alternatives are computationally intensive, requiring integration over all possible...

  5. Chain-Chain Based Routing Protocol

    Directory of Open Access Journals (Sweden)

    Samia A Ali

    2011-05-01

    Full Text Available Wireless sensor network (WSN is an emerging technology for monitoring physical world. WSNs consist of large numbers of sensor nodes operated by battery mostly in harsh environment. Thus energy conservation is a primary issue for organization of these sensor nodes. Another crucial issue is the data delivery time by sensor nodes to the sink node, especially in Military, medical fields, and security monitoring systems where minimum delay is desirable. Number of protocols has been proposed in the literature for routing. One of such protocols is the cluster based routing protocol LEACH (low energy adaptive clustering hierarchy. LEACH protocol organizes WSN into a set of clusters and a periodic voting for cluster head is performed in order to be evenly distributed among all the sensors of the WSN. This periodical cluster head voting in LEACH, however, consumes an amount of non-negligible energy and other resources. For energy conservation, PEGASIS (power efficient gathering in sensor information systems a near optimal chain-based protocol has been proposed, however, it is faced with the challenge of long delay for the transmitted data. Another routing protocol called CCM (Chain-Cluster based Mixed routing, which is mainly a hybrid of LEACH and PEGASIS is proposed, the consumed energy increases as network size increases. In this paper, we propose an efficient routing protocol called CCBRP (Chain-Chain based routing protocol, it achieves both minimum energy consumption and minimum delay. The CCBRP protocol mainly divides a WSN into a number of chains (Greedy algorithm is used to form each chain as in PEGSIS protocol and runs in two phases. In the first phase, sensor nodes in each chain transmit data to their chain leader nodes in parallel. In the second phase, all chain leader nodes form a chain (also, using Greedy algorithm and choose randomly a leader node then all chain leader nodes send their data to this chosen leader node. This chosen leader node

  6. Airway branching morphogenesis in three dimensional culture

    Directory of Open Access Journals (Sweden)

    Gudjonsson Thorarinn

    2010-11-01

    Full Text Available Abstract Background Lungs develop from the fetal digestive tract where epithelium invades the vascular rich stroma in a process called branching morphogenesis. In organogenesis, endothelial cells have been shown to be important for morphogenesis and the maintenance of organ structure. The aim of this study was to recapitulate human lung morphogenesis in vitro by establishing a three dimensional (3D co-culture model where lung epithelial cells were cultured in endothelial-rich stroma. Methods We used a human bronchial epithelial cell line (VA10 recently developed in our laboratory. This cell line cell line maintains a predominant basal cell phenotype, expressing p63 and other basal markers such as cytokeratin-5 and -14. Here, we cultured VA10 with human umbilical vein endothelial cells (HUVECs, to mimic the close interaction between these cell types during lung development. Morphogenesis and differentiation was monitored by phase contrast microscopy, immunostainings and confocal imaging. Results We found that in co-culture with endothelial cells, the VA10 cells generated bronchioalveolar like structures, suggesting that lung epithelial branching is facilitated by the presence of endothelial cells. The VA10 derived epithelial structures display various complex patterns of branching and show partial alveolar type-II differentiation with pro-Surfactant-C expression. The epithelial origin of the branching VA10 colonies was confirmed by immunostaining. These bronchioalveolar-like structures were polarized with respect to integrin expression at the cell-matrix interface. The endothelial-induced branching was mediated by soluble factors. Furthermore, fibroblast growth factor receptor-2 (FGFR-2 and sprouty-2 were expressed at the growing tips of the branching structures and the branching was inhibited by the FGFR-small molecule inhibitor SU5402. Discussion In this study we show that a human lung epithelial cell line can be induced by endothelial cells to

  7. The specific carbon isotopic compositions of branched and cyclic hydrocarbons from Fushun oil shale

    Institute of Scientific and Technical Information of China (English)

    DUAN Yi; WU Baoxiang; ZHENG Guodong; ZHANG Hui; ZHENG Chaoyang

    2004-01-01

    Various branched and cyclic hydrocarbons are isolated from the Fushun oil shale and their carbon isotopes are determined. The analytical results show that the branched and cyclic hydrocarbons are fully separated from n-alkanes by 5 A Molecular-sieve adduction using long time and cold solvent. The branched and cyclic hydrocarbon fraction obtained by this method is able to satisfy the analytic requests of GC-IRMS. The carbon isotopic compositions of these branched and cyclic hydrocarbons obtained from the sample indicate that they are derived from photoautotrophic algae, chemoautotrophic bacteria (-3.4‰ --39.0‰) and methanotrophic bacteria (-38.4‰--46.3‰). However the long-chain 2-methyl-branched alkanes indicate that their carbon isotopic compositions reflect biological origin from higher plants. The carbon isotopic composition of C30 4-methyl sterane (-22.1‰) is the heaviest in all studied ste- ranes, showing that the carbon source or growth condition for its precursor, dinoflagellate, may be different from that of regular steranes. The variation trend of δ13C values between isomers of hopanes shows that 13C-enriched precursors take precedence in process of their epimerization. Methanotrophic hopanes presented reveal the processes of strong transformation of organic matter and cycling of organic carbon in the water column and early diagenesis of oil shale.

  8. Discrete Quantum Markov Chains

    CERN Document Server

    Faigle, Ulrich

    2010-01-01

    A framework for finite-dimensional quantum Markov chains on Hilbert spaces is introduced. Quantum Markov chains generalize both classical Markov chains with possibly hidden states and existing models of quantum walks on finite graphs. Quantum Markov chains are based on Markov operations that may be applied to quantum systems and include quantum measurements, for example. It is proved that quantum Markov chains are asymptotically stationary and hence possess ergodic and entropic properties. With a quantum Markov chain one may associate a quantum Markov process, which is a stochastic process in the classical sense. Generalized Markov chains allow a representation with respect to a generalized Markov source model with definite (but possibly hidden) states relative to which observables give rise to classical stochastic processes. It is demonstrated that this model allows for observables to violate Bell's inequality.

  9. Measurement of tau lepton branching fractions

    International Nuclear Information System (INIS)

    We present τ- lepton branching fraction measurements based on data from the TPC/Two-Gamma detector at PEP. Using a sample ofτ- → ντK-π+π- events, we examine the resonance structure of the K-π+π- system and obtain the first measurements of branching fractions for τ- → ντK1-(1270) and τ- → ντK1-(1400). We also describe a complete set of branching fraction measurements in which all the decays of the τ- lepton are separated into classes defined by the identities of the charged particles and an estimate of the number of neutrals. This is the first such global measurement with decay classes defined by the four possible charged particle species, e, μ, π, and K

  10. Geometry optimization of branchings in vascular networks

    Science.gov (United States)

    Khamassi, Jamel; Bierwisch, Claas; Pelz, Peter

    2016-06-01

    Progress has been made in developing manufacturing technologies which enable the fabrication of artificial vascular networks for tissue cultivation. However, those networks are rudimentary designed with respect to their geometry. This restricts long-term biological functionality of vascular cells which depends on geometry-related fluid mechanical stimuli and the avoidance of vessel occlusion. In the present work, a bioinspired geometry optimization for branchings in artificial vascular networks has been conducted. The analysis could be simplified by exploiting self-similarity properties of the system. Design rules in the form of two geometrical parameters, i.e., the branching angle and the radius ratio of the daughter branches, are derived using the wall shear stress as command variable. The numerical values of these parameters are within the range of experimental observations. Those design rules are not only beneficial for tissue engineering applications. Moreover, they can be used as indicators for diagnoses of vascular diseases or for the layout of vascular grafts.

  11. Heterogeneity of coronary arterial branching geometry

    Science.gov (United States)

    Wan, Shu-Yen; Reyes, Denise A.; Higgins, William E.; Ritman, Erik L.

    2000-04-01

    Past measurements of arterial branching geometry have indicated that the branching geometry is somewhat consistent with an optimal trade-off between the work needed to build and maintain the arterial tree and the work needed to operate the tree as a transport system. The branching geometry is also consistent with the mechanism that acutely adjusts the lumen diameter by way of maintaining a constant shear stress by dilating (or constricting) the arteries via the nitric oxide mechanism. However, those observations also indicate that there is considerable variation about the predicted optimization, both within any one individual and between individuals. Possible causes for this variation include: (1) measurement noise -- both due to the imprecision of the method but also the preparation of the specimen for applying the measurement technique, (2) the fact that the measurement task presents a major logistic problem, which increases as the vessel size decreases (but the number of branches correspondingly doubles at each branching) and results in progressive under-sampling as the vessel size decreases, (3) because of the logistic task involved the number of arterial trees analyzed is also greatly limited, and (4) there may indeed be actual heterogeneity in the geometry which is due to slight variation in implementation of the 'rules' used to construct a vascular tree. Indeed, it is this latter possibility that is of considerable physiological interest as it could result in the observed heterogeneity of organ perfusion and also provide some insight into the relative importance of 'initial ' conditions (i.e., how the vascular tree initially develops during embryogenesis) and the adaptive mechanisms operative in the maturing individual. The use of micro-CT imaging to provide 3D images of the intact vascular tree within the intact organ overcomes or minimizes the logistic problems listed above. It is the purpose of this study to examine whether variability in the branching

  12. 桃树修剪分枝模式的模拟%Modeling the Branching Patterns of Peach Tree Branches (Prunus persica) After Being Pruned

    Institute of Scientific and Technical Information of China (English)

    夏宁; 李保国; 邓西民; 郭焱

    2004-01-01

    在不同修剪手法下,对栽培桃树(Prunuspersica(L.)Batsch)不同母枝上的分枝模式进行了比较研究.从分枝模式来看:修剪后的母枝基本由3个不同的区域组成,基部是不萌发的潜伏芽形成的未分枝区域;中部是延迟分枝和多次分枝组成的分枝区域(主要的枝条类型有短枝、长枝和多次枝);顶部是被剪除的部分.我们通过隐式半马尔可夫模型来模拟这一分枝模式,主要是定量描述1次枝和多次枝在母枝上的数量及其分布状况.在上述模型中,未分枝区、延迟分枝区和多次分枝区称为瞬时态,被剪除的部分称为吸收态.模拟的结果与观察的结果进行对比后发现,两者具有很好的一致性.这说明隐式半马尔可夫模型是模拟植物分枝过程的一种有效方法,尽管隐式半马尔可夫链模型只是一个描述性的模型,但仍能对其所描述的生物现象进行解释,在预测修剪手法对母枝分枝模式影响方面比传统的方法具有明显的优势.本研究结果是建立三维虚拟桃树树冠分枝结构的基础.%The shoot branching patterns of the two-year-old branches of peach trees (Prunus parsica (L.) Batsch cv. Elberta) were compared with different pruning measures. The branches were divided into a basal non-branching zone, a proleptic branching zone, a sylleptic branching zone and the part removed. We used the hidden semi-Markov model to capture the branching patterns. The final results showed that theoretical probability distributions of diverse lateral shoots of the parent branches calculated on the basis of the parameters of the hidden semi-Markov chain model were in good agreement with probabilities extracted from the observed data. This paper described the quantitative effects of pruning on branching architecture of a parent branch, taking into account of branch morphology. Results suggest that the hidden semi-Markov model could be used as an effective tool to describe the

  13. The branching channel network in the Yangtze Estuary

    NARCIS (Netherlands)

    Wang, Z.B.; Ding, P.X.

    2012-01-01

    The channels in the Yangtze Estuary have an ordered-branching structure: The estuary is first divided by the Chongming Island into the North Branch and the South Branch. Then the South Branch is divided into the North Channel and South Channel by the Islands Changxing and Hengsha. The South Channel

  14. General collision branching processes with two parameters

    Institute of Scientific and Technical Information of China (English)

    CHEN AnYue; LI JunPing

    2009-01-01

    A new class of branching models, the general collision branching processes with two parameters, is considered in this paper. For such models, it is necessary to evaluate the absorbing probabilities and mean extinction times for both absorbing states. Regularity and uniqueness criteria are firstly established. Explicit expressions are then obtained for the extinction probability vector, the mean extinction times and the conditional mean extinction times. The explosion behavior of these models is investigated and an explicit expression for mean explosion time is established. The mean global holding time is also obtained. It is revealed that these properties are substantially different between the super-explosive and sub-explosive cases.

  15. Logic, planning agency and branching time

    Directory of Open Access Journals (Sweden)

    Ricardo Souza Silvestre

    2010-12-01

    Full Text Available The purpose of this paper is to give a formal account of a kind of agency so far neglected in the field of philosophical modal logic of action: planning agency. In doing this we follow the standard approach of modal logics of agency exemplified by the works of Belnap, Chellas and Pörn. Since we believe there is a close relation between planning, time and indeterminism, we use the theory of branching time as a conceptual framework for investigating the basic features of planning agency. Besides introducing a branching-time semantics, we also provide a calculus sound and complete with respect to this semantics.

  16. Branch and Bound Experiments in Convex Nonlinear Integer Programming

    OpenAIRE

    Omprakash K. Gupta; Ravindran, A

    1985-01-01

    The branch and bound principle has long been established as an effective computational tool for solving mixed integer linear programming problems. This paper investigates the computational feasibility of branch and bound methods in solving convex nonlinear integer programming problems. The efficiency of a branch and bound method often depends on the rules used for selecting the branching variables and branching nodes. Among others, the concepts of pseudo-costs and estimations are implemented ...

  17. Effect of left bundle branch block on TIMI frame count

    OpenAIRE

    Hatice Tolunay; Ahmet Kasapkara; İsa Öner Yüksel; Nurcan Başar; Ayşe Saatcı Yaşar; Mehmet Bilge

    2010-01-01

    Aim: Left bundle branch block is an independent risk factorfor cardiac mortality. In this study we aimed to evaluatecoronary blood flow with TIMI frame count in patients with left bundle branch block and angiographically proven normal coronary arteries.Materials and methods: We retrospectively studied 17 patients with left bundle branch block and as a control group 16 patients without left bundle branch block. All patientshad angiographically proven normal coronary arteries.Left bundle branch...

  18. The unique branching patterns of Deinococcus glycogen branching enzymes are determined by their N-terminal domains.

    NARCIS (Netherlands)

    Palomo, M.; Kralj, S.; van der Maarel, M. J. E. C.; Dijkhuizen, L.

    2009-01-01

    Glycogen branching enzymes (GBE) or 1,4-alpha-glucan branching enzymes (EC 2.4.1.18) introduce alpha-1,6 branching points in alpha-glucans, e.g., glycogen. To identify structural features in GBEs that determine their branching pattern specificity, the Deinococcus geothermalis and Deinococcus radiodu

  19. Geometric ergodicity of a hybrid sampler for Bayesian inference of phylogenetic branch lengths.

    Science.gov (United States)

    Spade, David A; Herbei, Radu; Kubatko, Laura S

    2015-10-01

    One of the fundamental goals in phylogenetics is to make inferences about the evolutionary pattern among a group of individuals, such as genes or species, using present-day genetic material. This pattern is represented by a phylogenetic tree, and as computational methods have caught up to the statistical theory, Bayesian methods of making inferences about phylogenetic trees have become increasingly popular. Bayesian inference of phylogenetic trees requires sampling from intractable probability distributions. Common methods of sampling from these distributions include Markov chain Monte Carlo (MCMC) and Sequential Monte Carlo (SMC) methods, and one way that both of these methods can proceed is by first simulating a tree topology and then taking a sample from the posterior distribution of the branch lengths given the tree topology and the data set. In many MCMC methods, it is difficult to verify that the underlying Markov chain is geometrically ergodic, and thus, it is necessary to rely on output-based convergence diagnostics in order to assess convergence on an ad hoc basis. These diagnostics suffer from several important limitations, so in an effort to circumvent these limitations, this work establishes geometric convergence for a particular Markov chain that is used to sample branch lengths under a fairly general class of nucleotide substitution models and provides a numerical method for estimating the time this Markov chain takes to converge.

  20. Supply Chain Management og Supply Chain costing

    DEFF Research Database (Denmark)

    Nielsen, Steen; Mortensen, Ole

    2002-01-01

    Formålet med denne artikel er at belyse de muligheder som ligger i at integrere virksomhedens økonomiske styring med begrebet Supply Chain Management (SCM). Dette søges belyst ved først at beskrive den teoretiske ramme, hvori SCM indgår. Herefter analyseres begrebet Supply Chain Costing (SCC) som...... Århus. Et resultat er, at via begrebet Supply Chain Costing skabes der mulighed for at måle logistikkædens aktiviteter i kr./øre. Anvendelsen af denne information har også strategisk betydning for at kunne vælge kunde og leverandør. Ved hjælp af integrationen skabes der også helt nye mulighed...

  1. Understanding the Chain Fountain

    CERN Document Server

    Biggins, John Simeon

    2013-01-01

    If a chain is initially at rest in a beaker at a height h1 above the ground, and the end of the chain is pulled over the rim of the beaker and down towards the ground and then released, the chain will spontaneously "flow" out of the beaker under gravity. Furthermore, if h1 is sufficient, the beads do not simply drag over the edge of the beaker but form a fountain reaching a height h2 above it. We show that the formation of a fountain requires that the beads come into motion not only by being pulled upwards by the part of the chain immediately above the pile, but also by being pushed upwards by an anomalous reaction force from the pile of stationary chain. We propose possible origins for this force, argue that its magnitude will be proportional to the square of the chain velocity, and predict and verify experimentally that h2 is proportional to h1.

  2. On the red giant branch mass loss in 47 Tucanae: Constraints from the horizontal branch morphology

    CERN Document Server

    Salaris, Maurizio; Pietrinferni, Adriano

    2016-01-01

    We obtain stringent constraints on the actual efficiency of mass loss for red giant branch stars in the Galactic globular cluster 47 Tuc, by comparing synthetic modeling based on stellar evolution tracks with the observed distribution of stars along the horizontal branch in the colour-magnitude-diagram. We confirm that the observed, wedge-shaped distribution of the horizontal branch can be reproduced only by accounting for a range of initial He abundances --in agreement with inferences from the analysis of the main sequence-- and a red giant branch mass loss with a small dispersion. We have carefully investigated several possible sources of uncertainty that could affect the results of the horizontal branch modeling, stemming from uncertainties in both stellar model computations and the cluster properties such as heavy element abundances, reddening and age. We determine a firm lower limit of ~0.17$Mo for the mass lost by red giant branch stars, corresponding to horizontal branch stellar masses between ~0.65Mo ...

  3. Medial branch neurotomy in low back pain

    International Nuclear Information System (INIS)

    This study aimed to assess the effectiveness of pulsed radiofrequency medial branch dorsal ramus neurotomy in patients with facet joint syndrome. From January 2008 to April 2010, 92 patients with facet joint syndrome diagnosed by strict inclusion criteria and controlled diagnostic blocks undergone medial branch neurotomy. We did not exclude patients with failed back surgery syndrome (FBSS). Electrodes (20G) with 5-mm active tip were placed under fluoroscopy guide parallel to medial branch. Patients were followed up by physical examination and by Visual Analog Scale and Oswestry Disability Index at 1, 6, and 12 months. In all cases, pain improvement was statistically significant and so quality of life. Three non-FBSS patients had to undergo a second neurotomy because of non-satisfactory pain decrease. Complications were reported in no case. Medial branch radiofrequency neurotomy has confirmed its well-established effectiveness in pain and quality of life improvement as long as strict inclusion criteria be fulfilled and nerve ablation be accomplished by parallel electrode positioning. This statement can be extended also to FBSS patients. (orig.)

  4. Branching Processes with Immigration and Related Topics

    Institute of Scientific and Technical Information of China (English)

    LI Zeng-hu

    2006-01-01

    This is a survey on the recent progresses in the study of branching processes with immigration,generalized Ornstein-Uhlenbeck processes,and affine Markov processes.We mainly focus on the applications of skew convolution semigroups and the connections in those processes.

  5. Medial branch neurotomy in low back pain

    Energy Technology Data Exchange (ETDEWEB)

    Masala, Salvatore; Mammucari, Matteo; Simonetti, Giovanni [Interventional Radiology and Radiotherapy University ' ' Tor Vergata' ' , Department of Diagnostic and Molecular Imaging, Rome (Italy); Nano, Giovanni [Interventional Radiology and Radiotherapy University ' ' Tor Vergata' ' , Department of Diagnostic and Molecular Imaging, Rome (Italy); University ' ' Tor Vergata' ' , Department of Radiology, Rome (Italy); Marcia, Stefano [S. Giovanni di Dio Hospital, Department of Diagnostic and Molecular Imaging, Cagliari (Italy)

    2012-07-15

    This study aimed to assess the effectiveness of pulsed radiofrequency medial branch dorsal ramus neurotomy in patients with facet joint syndrome. From January 2008 to April 2010, 92 patients with facet joint syndrome diagnosed by strict inclusion criteria and controlled diagnostic blocks undergone medial branch neurotomy. We did not exclude patients with failed back surgery syndrome (FBSS). Electrodes (20G) with 5-mm active tip were placed under fluoroscopy guide parallel to medial branch. Patients were followed up by physical examination and by Visual Analog Scale and Oswestry Disability Index at 1, 6, and 12 months. In all cases, pain improvement was statistically significant and so quality of life. Three non-FBSS patients had to undergo a second neurotomy because of non-satisfactory pain decrease. Complications were reported in no case. Medial branch radiofrequency neurotomy has confirmed its well-established effectiveness in pain and quality of life improvement as long as strict inclusion criteria be fulfilled and nerve ablation be accomplished by parallel electrode positioning. This statement can be extended also to FBSS patients. (orig.)

  6. Infrared studies of asymptotic giant branch stars

    International Nuclear Information System (INIS)

    In this thesis studies are presented of asymptotic giant branch stars, which are thought to be an important link in the evolution of the galaxy. The studies were performed on the basis of data collected by the IRAS, the infrared astronomical satelite. 233 refs.; 33 figs.; 16 tabs

  7. 76 FR 60757 - Executive Branch Qualified Trusts

    Science.gov (United States)

    2011-09-30

    ... portfolio must meet the diversification requirements of Sec. 2634.406(b)(2) of this subpart. (2) In the case... of the trust's portfolio would be materially enhanced. Additionally, as with the blind trust, the... qualified trusts provisions for the executive branch in subparts D and E of 5 CFR part 2634 (see 57 FR...

  8. Branch II : Neutrino Oscillations at Low Energies

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, A., E-mail: anatael@in2p3.fr [CNRS/IN2P3. Laboratoire d' Astro-Particule et Cosmologie. 10 rue Alice Domont et Leonie Duquet. Paris. 75205. Cedex 13 (France); Volpe, C., E-mail: volpe@ipno.in2p3.fr [Institut de Physique Nucleaire Orsay and University of Paris XI,CNRS/IN2P3, F-91406 Orsay cedex (France)

    2011-08-15

    We summarize here briefly the experimental and theoretical results presented at the NOW2010 workshop during the parallel session Branch II 'Oscillations at low energies'. The topics have covered open problems and recent advances in solar neutrinos, reactor and geo-neutrinos, as well as neutrinos from core-collapse supernovae.

  9. Analýza informačnej podpory v supply chain manažmente a návrh jej optimalizácie

    OpenAIRE

    Vislocká, Martina

    2007-01-01

    Thesis focuses on analysis and optimization of Supply Chain Management information tools in the branch of DHL Exel Supply Chain. The aim of the project is the introduction of the company, characteristics of its Supply Chain environment, and optimization and description of its information tool.

  10. Food supply chains

    OpenAIRE

    Zhou, Qian

    2011-01-01

    The dissertation analyses food waste in global supply chain. From the related managerial literature, the process of supply chain operation, from agriculture, manufacturing, warehouses, retailers to customers are explained clearly. Then the reasons and characteristics of food wastes in any point of food supply chain are analyzed. From some case studies and questionnaire investigation, some corresponding methods to reduce food waste are put forward in the following. Lastly, in terms of method s...

  11. Economy, market and chain

    OpenAIRE

    Sukkel, W.; Hommes, M.

    2009-01-01

    In their pursuit of growth and professionalisation, the Dutch organic sector focuses primarily on market development. But how do you stimulate the market for organic foods? This is the subject of many research projects concerning market, consumer preferences and the supply chain. These projects focus specifically at consumer purchasing behaviour, product development, supply chain formation and minimising cost price. As a rule, this research takes place in close cooperation with chain actors

  12. Supply Chain Collaboration

    OpenAIRE

    Meca, Ana; Timmer, Judith

    2008-01-01

    In this chaper, we have reviewed and surveyed the literature on supply chain collaboration. As mentioned above, the game theory models that include cooperative behaviour among retailers seem to be a natural framework to model cooperation (collaboration) in supply chains that consist of a supplier and a finite number of retailers. Various researchers in this area have already adopted several cooperative models dealing with supply chain coordination, and it is expected to see many more in the n...

  13. Sustainable Supply Chain Management

    OpenAIRE

    Geentjens, Marlies

    2013-01-01

    This project investigates the phenomena Sustainable Supply Chain Management. The point of departure is Supply Chain Management, which we analyse in order to lock into an understanding of the development that occur when implementing sustainability. In the quest for higher understanding of the interlocking mechanisms of supply chain management, we combine a theoretical approach to the developmnent of sustainability with some relevant case-examples (mainly depicting IKEA). This focal point g...

  14. Supply chain components

    Directory of Open Access Journals (Sweden)

    Vieraşu, T.

    2011-01-01

    Full Text Available In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  15. Supply chain components

    OpenAIRE

    Vieraşu, T.; Bălăşescu, M.

    2011-01-01

    In this article I will go through three main logistics components, which are represented by: transportation, inventory and facilities, and the three secondary logistical components: information, production location, price and how they determine performance of any supply chain. I will discuss then how these components are used in the design, planning and operation of a supply chain. I will also talk about some obstacles a supply chain manager may encounter.

  16. The AFCRL Lunar amd Planetary Research Branch

    Science.gov (United States)

    Price, Stephan D.

    2011-07-01

    The Lunar and Planetary research program led by Dr John (Jack) Salisbury in the 1960s at the United States Air Force Cambridge Research Laboratories (AFCRL) investigated the surface characteristics of Solar System bodies. The Branch was one of the first groups to measure the infrared spectra of likely surface materials in the laboratory under appropriate vacuum and temperature conditions. The spectral atlases created from the results were then compared to photometric and spectral measurements obtained from ground- and balloon-based telescopes to infer the mineral compositions and physical conditions of the regoliths of the Moon, Mars and asteroids. Starting from scratch, the Branch initially sponsored observations of other groups while its in-house facilities were being constructed. The earliest contracted efforts include the spatially-resolved mapping of the Moon in the first half of the 1960s by Richard W. Shorthill and John W. Saari of the Boeing Scientific Research Laboratories in Seattle. This effort ultimately produced isophotal and isothermal contour maps of the Moon during a lunation and time-resolved thermal images of the eclipsed Moon. The Branch also sponsored probe rocket-based experiments flown by Riccardo Giacconi and his group at American Science and Engineering Inc. that produced the first observations of X-ray stars in 1962 and later the first interferometric measurement of the ozone and C02 emission in the upper atmosphere. The Branch also made early use of balloon-based measurements. This was a singular set of experiments, as these observations are among the very few mid-infrared astronomical measurements obtained from a balloon platform. Notable results of the AFCRL balloon flights were the mid-infrared spectra of the spatially-resolved Moon obtained with the University of Denver mid-infrared spectrometer on the Branch's balloon-borne 61-cm telescope during a 1968 flight. These observations remain among the best available. Salisbury also funded

  17. The Branching Bifurcation of Adaptive Dynamics

    Science.gov (United States)

    Della Rossa, Fabio; Dercole, Fabio; Landi, Pietro

    2015-06-01

    We unfold the bifurcation involving the loss of evolutionary stability of an equilibrium of the canonical equation of Adaptive Dynamics (AD). The equation deterministically describes the expected long-term evolution of inheritable traits — phenotypes or strategies — of coevolving populations, in the limit of rare and small mutations. In the vicinity of a stable equilibrium of the AD canonical equation, a mutant type can invade and coexist with the present — resident — types, whereas the fittest always win far from equilibrium. After coexistence, residents and mutants effectively diversify, according to the enlarged canonical equation, only if natural selection favors outer rather than intermediate traits — the equilibrium being evolutionarily unstable, rather than stable. Though the conditions for evolutionary branching — the joint effect of resident-mutant coexistence and evolutionary instability — have been known for long, the unfolding of the bifurcation has remained a missing tile of AD, the reason being related to the nonsmoothness of the mutant invasion fitness after branching. In this paper, we develop a methodology that allows the approximation of the invasion fitness after branching in terms of the expansion of the (smooth) fitness before branching. We then derive a canonical model for the branching bifurcation and perform its unfolding around the loss of evolutionary stability. We cast our analysis in the simplest (but classical) setting of asexual, unstructured populations living in an isolated, homogeneous, and constant abiotic environment; individual traits are one-dimensional; intra- as well as inter-specific ecological interactions are described in the vicinity of a stationary regime.

  18. Synthesis of Well-Defined Three-Arm Star-Branched Polystyrene through Arm-First Coupling Approach by Atom Transfer Radical Polymerization

    OpenAIRE

    Syed Shahabuddin; Fatem Hamime Ismail; Sharifah Mohamad; Norazilawati Muhamad Sarih

    2015-01-01

    Here we describe a simple route to synthesize three-arm star-branched polystyrene. Atom transfer radical polymerization technique has been utilized to yield branched polystyrene involving Williamson coupling strategy. Initially a linear polymeric chain of predetermined molecular weight has been synthesized which is further end-functionalized into a primary alkyl bromide moiety, a prime requisition for Williamson reaction. The end-functionalized polymer is then coupled using 1,1,1-tris(4-hydro...

  19. 3rd Workshop on Branching Processes and their Applications

    CERN Document Server

    González, Miguel; Gutiérrez, Cristina; Martínez, Rodrigo; Minuesa, Carmen; Molina, Manuel; Mota, Manuel; Ramos, Alfonso; WBPA15

    2016-01-01

    This volume gathers papers originally presented at the 3rd Workshop on Branching Processes and their Applications (WBPA15), which was held from 7 to 10 April 2015 in Badajoz, Spain (http://branching.unex.es/wbpa15/index.htm). The papers address a broad range of theoretical and practical aspects of branching process theory. Further, they amply demonstrate that the theoretical research in this area remains vital and topical, as well as the relevance of branching concepts in the development of theoretical approaches to solving new problems in applied fields such as Epidemiology, Biology, Genetics, and, of course, Population Dynamics. The topics covered can broadly be classified into the following areas: 1. Coalescent Branching Processes 2. Branching Random Walks 3. Population Growth Models in Varying and Random Environments 4. Size/Density/Resource-Dependent Branching Models 5. Age-Dependent Branching Models 6. Special Branching Models 7. Applications in Epidemiology 8. Applications in Biology and Genetics Offer...

  20. Value Chain Engineering

    DEFF Research Database (Denmark)

    Wæhrens, Brian Vejrum; Slepniov, Dmitrij

    2015-01-01

    This workbook is recommended for the attention of students of and managers in Danish small and medium sized enterprises (SMEs). Danish SMEs are currently facing a number of key challenges related to their position in global value chains. This book provides an insight into value chain management t...

  1. Qualitative and quantitative analysis of branches in dextran using high-performance anion exchange chromatography coupled to quadrupole time-of-flight mass spectrometry.

    Science.gov (United States)

    Yi, Lin; Ouyang, Yilan; Sun, Xue; Xu, Naiyu; Linhardt, Robert J; Zhang, Zhenqing

    2015-12-01

    Dextran, a family of natural polysaccharides, consists of an α (1→6) linked-glucose main (backbone) chain having a number of branches. The determination of the types and the quantities of branches in dextran is important in understanding its various biological roles. In this study, a hyphenated method using high-performance anion exchange chromatography (HPAEC) in parallel with pulsed amperometric detection (PAD) and mass spectrometry (MS) was applied to qualitative and quantitative analysis of dextran branches. A rotary cation-exchange cartridge array desalter was used for removal of salt from the HPAEC eluent making it MS compatible. MS and MS/MS were used to provide structural information on the enzymatically prepared dextran oligosaccharides. PAD provides quantitative data on the ratio of enzyme-resistant, branched dextran oligosaccharides. Both the types and degree of branching found in a variety of dextrans could be simultaneously determined online using this method.

  2. Organization and Structure of Branched Amphipathic Oligopeptide Bilayers.

    Science.gov (United States)

    Jia, Zhiguang; Whitaker, Susan K; Tomich, John M; Chen, Jianhan

    2016-09-27

    A class of self-assembling branched amphiphilic peptide capsules (BAPCs) was recently developed that could serve as a new drug delivery vehicle. BAPCs can encapsulate solutes up to ∼12 kDa during assembly, are unusually stable, and are readily taken up by cells with low cytotoxicity. Coarse-grained simulations have supported that BAPCs are defined by bilayers that resemble those formed by diacyl phospholipids. Here, atomistic simulations were performed to characterize the structure and organization of bilayers formed by three branched amphiphilic peptides (BAPs): bis(Ac-FLIVIGSII)-K-K4-CO-NH2, bis(Ac-CHA-LIVIGSII)-K-K4-CO-NH2, and bis(Ac-FLIVI)-K-K4-CO-NH2. The results show BAPs form a network of intra- and intermolecular backbone hydrogen bonds within the same leaflet in addition to hydrophobic side-chain interactions. The terminal residues of two leaflets form an interdigitation region locking two leaflets together. The phenyl groups in bis(Ac-FLIVIGSII)-K-K4-CO-NH2 and bis(Ac-FLIVI)-K-K4-CO-NH2 are tightly packed near the bilayer center but do not formed ordered structures with specific π-π stacking. Replacing phenyl groups with the cyclohexane side chain only slightly increases the level of disorder in bilayer structures and thus should not significantly affect the stability, consistent with experimental results on bis(Ac-CHA-LIVIGSII)-K-K4-CO-NH2 BAPCs. Self-assembly simulations further suggest that leaflet interdigitation likely occurs at early stages of BAPC formation. Atomistic simulations also reveal that the BAPC bilayers are highly permeable to water. This prediction was validated using fluorescence measurements of encapsulated self-quenching dye upon transferring BAPCs to buffers with different salt concentrations. Improved understanding of the organization and structure of BAPC bilayers at the atomic level will provide a basis for future rational modifications of BAP sequence to improve BAPC properties as a new class of delivery vehicle. PMID

  3. Integrated supply chain risk management

    OpenAIRE

    Riaan Bredell; Jackie Walters

    2007-01-01

    Integrated supply chain risk management (ISCRM) has become indispensable to the theory and practice of supply chain management. The economic and political realities of the modern world require not only a different approach to supply chain management, but also bold steps to secure supply chain performance and sustainable wealth creation. Integrated supply chain risk management provides supply chain organisations with a level of insight into their supply chains yet to be achieved. If correctly ...

  4. Supply Chain Connectivity: Enhancing Participation in the Global Supply Chain

    OpenAIRE

    Patalinghug, Epictetus E.

    2015-01-01

    Supply chain connectivity is vital for the efficient flow of trade among APEC economies. This paper reviews the literature and supply chain management, describes the barriers to enhancing participation in global supply chain, analyzes the various measures of supply chain performance, and suggests steps for the Philippines to fully reap the benefits of the global value chain.

  5. Fort Collins Science Center Ecosystem Dynamics Branch

    Science.gov (United States)

    Wilson, Jim; Melcher, C.; Bowen, Z.

    2009-01-01

    Complex natural resource issues require understanding a web of interactions among ecosystem components that are (1) interdisciplinary, encompassing physical, chemical, and biological processes; (2) spatially complex, involving movements of animals, water, and airborne materials across a range of landscapes and jurisdictions; and (3) temporally complex, occurring over days, weeks, or years, sometimes involving response lags to alteration or exhibiting large natural variation. Scientists in the Ecosystem Dynamics Branch of the U.S. Geological Survey, Fort Collins Science Center, investigate a diversity of these complex natural resource questions at the landscape and systems levels. This Fact Sheet describes the work of the Ecosystems Dynamics Branch, which is focused on energy and land use, climate change and long-term integrated assessments, herbivore-ecosystem interactions, fire and post-fire restoration, and environmental flows and river restoration.

  6. Photovoltaic Program Branch annual report, FY 1989

    Energy Technology Data Exchange (ETDEWEB)

    Summers, K A [ed.

    1990-03-01

    This report summarizes the progress of the Photovoltaic (PV) Program Branch of the Solar Energy Research Institute (SERI) from October 1, 1988, through September 30, 1989. The branch is responsible for managing the subcontracted portion of SERI's PV Advanced Research and Development Project. In fiscal year (FY) 1989, this included nearly 50 subcontracts, with a total annualized funding of approximately $13.1 million. Approximately two-thirds of the subcontracts were with universities, at a total funding of nearly $4 million. The six technical sections of the report cover the main areas of the subcontracted program: Amorphous Silicon Research, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, New Ideas, and University Participation. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1989, and future research directions. Each report will be cataloged individually.

  7. Branch management into micropipeline joint dot

    Directory of Open Access Journals (Sweden)

    Dimitar Tyanev

    2011-11-01

    Full Text Available This paper considers problems related to hardware implementation of computational process with conditional jumps. Hardware refers to asynchronous pipeline organization at microoperational level. Exploration is dedicated to one of the tasks presented in (Tyanev, D., 2009 concerning to micropipeline controller design to control micropipeline stage into joint dot of branch algorithm. Joint dot is the point at which few preceding branches are combined. It appears inevitably into conditional jump structures and this is the reason for the actuality of its problem. Analysis of this new task is presented and request arbitration functioning principles are formulated for the incoming to joint dot requests. The arbiter is responsible for the fair choice on which depends steady peformance of separate pipeline brances. Paper also describes pipeline controller synthesis and analysis of its operation in two variants: about 2-phase and 4-phase data transfer protocol. The synthesized asynchronous arbiter scheme is invariant to the type of pipeline protocol.

  8. Branching Dynamics of Viral Information Spreading

    CERN Document Server

    Iribarren, José Luis

    2011-01-01

    Despite its importance for rumors or innovations propagation, peer-to-peer collaboration, social networking or Marketing, the dynamics of information spreading is not well understood. Since the diffusion depends on the heterogeneous patterns of human behavior and is driven by the participants' decisions, its propagation dynamics shows surprising properties not explained by traditional epidemic or contagion models. Here we present a detailed analysis of our study of real Viral Marketing campaigns where tracking the propagation of a controlled message allowed us to analyze the structure and dynamics of a diffusion graph involving over 31,000 individuals. We found that information spreading displays a non-Markovian branching dynamics that can be modeled by a two-step Bellman-Harris Branching Process that generalizes the static models known in the literature and incorporates the high variability of human behavior. It explains accurately all the features of information propagation under the "tipping-point" and can...

  9. General collision branching processes with two parameters

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A new class of branching models,the general collision branching processes with two parameters,is considered in this paper.For such models,it is necessary to evaluate the absorbing probabilities and mean extinction times for both absorbing states.Regularity and uniqueness criteria are firstly established.Explicit expressions are then obtained for the extinction probability vector,the mean extinction times and the conditional mean extinction times.The explosion behavior of these models is investigated and an explicit expression for mean explosion time is established.The mean global holding time is also obtained.It is revealed that these properties are substantially different between the super-explosive and sub-explosive cases.

  10. ON MARKOV CHAINS IN SPACE-TIME RANDOM ENVIRONMENTS

    Institute of Scientific and Technical Information of China (English)

    Hu Dihe; Hu Xiaoyu

    2009-01-01

    In Section 1, the authors establish the models of two kinds of Markov chains in space-time random environments (MCSTRE and MCSTRE(+)) with Abstract state space. In Section 2, the authors construct a MCSTRE and a MCSTRE(+) by an initial distribution Ф and a random Markov kernel (RMK) p(γ). In Section 3, the authors establish several equivalence theorems on MCSTRE and MCSTRE(+). Finally, the authors give two very important examples of MCMSTRE, the random walk in spce-time random environment and the Markov branching chain in space-time random environment.

  11. A role for branched-chain amino acids in reducing central fatigue.

    Science.gov (United States)

    Blomstrand, Eva

    2006-02-01

    Several factors have been identified to cause peripheral fatigue during exercise, whereas the mechanisms behind central fatigue are less well known. Changes in the brain 5-hydroxytryptamine (5-HT) level is one factor that has been suggested to cause fatigue. The rate-limiting step in the synthesis of 5-HT is the transport of tryptophan across the blood-brain barrier. This transport is influenced by the fraction of tryptophan available for transport into the brain and the concentration of the other large neutral amino acids, including the BCAAs (leucine, isoleucine, and valine), which are transported via the same carrier system. Studies in human subjects have shown that the plasma ratio of free tryptophan (unbound to albumin)/BCAAs increases and that tryptophan is taken up by the brain during endurance exercise, suggesting that this may increase the synthesis of 5-HT in the brain. Ingestion of BCAAs increases their concentration in plasma. This may reduce the uptake of tryptophan by the brain and also 5-HT synthesis and thereby delay fatigue. Accordingly, when BCAAs were supplied to human subjects during a standardized cycle ergometer exercise their ratings of perceived exertion and mental fatigue were reduced, and, during a competitive 30-km cross-country race, their performance on different cognitive tests was improved after the race. In some situations the intake of BCAAs also improves physical performance. The results also suggest that ingestion of carbohydrates during exercise delays a possible effect of BCAAs on fatigue since the brain's uptake of tryptophan is reduced. PMID:16424144

  12. Chain-Branching Control of the Atomic Structure of Alkanethiol-Based Gold–Sulfur Interfaces

    DEFF Research Database (Denmark)

    Wang, Yun; Chi, Qijin; Zhang, Jingdong;

    2011-01-01

    Density functional theory structure calculations at 0 K and simulations at 300 K of observed high-resolution in situ scanning tunneling microscopy (STM) images reveal three different atomic-interface structures for the self-assembled monolayers (SAMs) of three isomeric butanethiols on Au(111): di...

  13. Kinetics of thermophilic, anaerobic oxidation of straight and branched chain butyrate and valerate

    DEFF Research Database (Denmark)

    Batstone, Damien J.; Pind, Peter Frode; Angelidaki, Irini

    2003-01-01

    in leucine (which produces i-valerate), and the modified model structure and stoichiometry as proposed here should be used. This requires no additional kinetic parameters and one additional dynamic concentration state variable (i-valerate) in addition to the variables in the base model. (C) 2003 Wiley...

  14. PGC-1α-Mediated Branched-Chain Amino Acid Metabolism in the Skeletal Muscle

    OpenAIRE

    Yukino Hatazawa; Miki Tadaishi; Yuta Nagaike; Akihito Morita; Yoshihiro Ogawa; Osamu Ezaki; Takako Takai-Igarashi; Yasuyuki Kitaura; Yoshiharu Shimomura; Yasutomi Kamei; Shinji Miura

    2014-01-01

    Peroxisome proliferator-activated receptor (PPAR) γ coactivator 1α (PGC-1α) is a coactivator of various nuclear receptors and other transcription factors, which is involved in the regulation of energy metabolism, thermogenesis, and other biological processes that control phenotypic characteristics of various organ systems including skeletal muscle. PGC-1α in skeletal muscle is considered to be involved in contractile protein function, mitochondrial function, metabolic regulation, intracellula...

  15. Chain-branching control of the atomic structure of alkanethiol-based gold-sulfur interfaces.

    Science.gov (United States)

    Wang, Yun; Chi, Qijin; Zhang, Jingdong; Hush, Noel S; Reimers, Jeffrey R; Ulstrup, Jens

    2011-09-28

    Density functional theory structure calculations at 0 K and simulations at 300 K of observed high-resolution in situ scanning tunneling microscopy (STM) images reveal three different atomic-interface structures for the self-assembled monolayers (SAMs) of three isomeric butanethiols on Au(111): direct binding to the Au(111) surface without pitting, binding to adatoms above a regular surface with extensive pitting, and binding to adatoms with local surface vacancies and some pitting. Thermal motions are shown to produce some observed STM features, with a very tight energy balance controlling the observed structures. Variation of the degree of substitution on the α carbon is found to significantly change the relative energies for interaction of the different types of adatom structures with the surface, while the nature of the surface cell, controlled primarily by inter-adsorbate steric interactions, controls substrate reorganization energies and adsorbate distortion energies. Most significantly, by manipulating these features, chemical control of the adsorbate can produce stable interfaces with surface pitting eliminated, providing new perspectives for technological applications of SAMs.

  16. Isolated 2-methylbutyrylglycinuria caused by short/branched-chain acyl-CoA dehydrogenase deficiency

    DEFF Research Database (Denmark)

    Andresen, B S; Christensen, E; Corydon, T J;

    2000-01-01

    of homozygosity for a 1228G-->A mutation in the patient. This mutation was not present in 118 control chromosomes. In vitro transcription/translation experiments and overexpression in COS cells confirmed the disease-causing nature of the mutant SBCAD protein and showed that ACAD-8 is an isobutyryl......-CoA dehydrogenase and that both wild-type proteins are imported into mitochondria and form tetramers. In conclusion, we report the first mutation in the SBCAD gene, show that it results in an isolated defect in isoleucine catabolism, and indicate that ACAD-8 is a mitochondrial enzyme that functions in valine...

  17. 2-ethylhydracrylic aciduria in short/branched-chain acyl-CoA dehydrogenase deficiency

    DEFF Research Database (Denmark)

    Korman, Stanley H; Andresen, Brage S; Zeharia, Avraham;

    2005-01-01

    of urine acylglycines is problematic. Excretion of 2-ethylhydracrylic acid (2-EHA), an intermediate formed in the normally minor R-pathway of L-isoleucine oxidation, has not previously been described in SBCADD. METHODS: Samples from four patients with 2-MBG excretion were analyzed by gas chromatography......-mass spectrometry for urine organic acids, quantification of 2-MBG, and chiral determination of 2-methylbutyric acid. Blood-spot acylcarnitines were measured by electrospray-tandem mass spectrometry. Mutations in the ACADSB gene encoding SBCAD were identified by direct sequencing. RESULTS: SBCADD was confirmed...... in each patient by demonstration of different ACADSB gene mutations. In multiple urine samples, organic acid analysis revealed a prominent 2-EHA peak usually exceeding the size of the 2-MBG peak. Approximately 40-46% of total 2-methylbutyric acid conjugates were in the form of the R-isomer, indicating...

  18. Branched chain mechanism of the decomposition of transition metal methyl derivatives

    International Nuclear Information System (INIS)

    Data on the thermal and photodecomposition of transition metal methyl derivatives are analyzed. Generalized kinetic model of the process is suggested. It is customary that the main acts of thermal and photodecomposition of transition metal methyl derivatives are homolysis of Me-C bonds, reactions of forming methyl radicals with nondecomposed Me-CH3 groups, decomposition intermediate Me-CH2. radicals with formation of methylene biradical and its following reactions with nondecomposed groups Me-CH3, Me-CH2-Me and Me3CH and solvent. It is shown that the suggested kinetic model allows to explain quantitatively the peculiarities of decomposition of transition metal methyl derivatives and composition of forming products. (author)

  19. Defects in muscle branched-chain amino acid oxidation contribute to impaired lipid metabolism

    Directory of Open Access Journals (Sweden)

    Carles Lerin

    2016-10-01

    Conclusions: Our data indicate that impaired muscle BCAA catabolism may contribute to the development of insulin resistance by perturbing both amino acid and fatty acid metabolism and suggest that targeting BCAA metabolism may hold promise for prevention or treatment of T2D.

  20. Polyunsaturated Branched-Chain Fatty Acid Geranylgeranoic Acid Induces Unfolded Protein Response in Human Hepatoma Cells.

    Directory of Open Access Journals (Sweden)

    Chieko Iwao

    Full Text Available The acyclic diterpenoid acid geranylgeranoic acid (GGA has been reported to induce autophagic cell death in several human hepatoma-derived cell lines; however, the molecular mechanism for this remains unknown. In the present study, several diterpenoids were examined for ability to induce XBP1 splicing and/or lipotoxicity for human hepatoma cell lines. Here we show that three groups of diterpenoids emerged: 1 GGA, 2,3-dihydro GGA and 9-cis retinoic acid induce cell death and XBP1 splicing; 2 all-trans retinoic acid induces XBP1 splicing but little cell death; and 3 phytanic acid, phytenic acid and geranylgeraniol induce neither cell death nor XBP1 splicing. GGA-induced ER stress/ unfolded protein response (UPR and its lipotoxicity were both blocked by co-treatment with oleic acid. The blocking activity of oleic acid for GGA-induced XBP1 splicing was not attenuated by methylation of oleic acid. These findings strongly suggest that GGA at micromolar concentrations induces the so-called lipid-induced ER stress response/UPR, which is oleate-suppressive, and shows its lipotoxicity in human hepatoma cells.

  1. Branched-chain fatty acid methyl esters as cold flow improvers for biodiesel

    Science.gov (United States)

    Biodiesel is an alternative diesel fuel derived mainly from the transesterification of plant oils with methanol or ethanol. This fuel is generally made from commodity oils such as canola, palm, or soybean and has a number of properties that make it compatible in compression-ignition engines. Despite...

  2. Comparative investigations of surface instabilities ("sharkskin") of a linear and a long-chain branched polyethylene

    OpenAIRE

    Burghelea, Teodor I.; Griess, Hans J.; Muenstedt, Helmut

    2010-01-01

    An experimental study of the physical origin and the mechanisms of the sharkskin instability is presented. Extrusion flows through a slit die are studied for two materials: a linear low density polyethylene (LLDPE) and a low density polyethylene (LDPE). By combining laser-Doppler velocimetry (LDV) with rheological measurements in both uniaxial extension and shear, the distributions of tensile and shear stresses in extrusion flows are measured for both materials.

  3. Computers in Some Branches of Applied Physiology .

    Directory of Open Access Journals (Sweden)

    S.S. Verma

    1994-04-01

    Full Text Available This paper reviews the applications of computers in the evaluation of different types of problems occuring in some branches of applied physiology. The recent applications of computers to perform advanced multivariate regression analysis for developing regression models in applied physiology are also highlighted. The regression models are practical significance for screening personnel in defence services, mines, industrial works, sports and the like.

  4. Minimum disparity estimation in controlled branching processes

    OpenAIRE

    Gonzalez, Miguel; Minuesa, Carmen; del Puerto, Ines

    2015-01-01

    Minimum disparity estimation in controlled branching processes is dealt with by assuming that the offspring law belongs to a general parametric family. Under some regularity conditions it is proved that the minimum disparity estimators proposed -based on the nonparametric maximum likelihood estimator of the offspring law when the entire family tree is observed- are consistent and asymptotic normally distributed. Moreover, it is discussed the robustness of the estimators proposed. Through a si...

  5. Branch Retinal Vein Occlusion and Its Management

    Institute of Scientific and Technical Information of China (English)

    Desmond; Archer

    1992-01-01

    The natural course of Branch Retinal Vein Occlusion is determined by the site and completeness of the occlusion, the integrity of arterial perfusion to the affected sector and the efficiency of the developing collateral circulation. Most patients with tributary vein occlusion have some capillary fall out and microvascular incompetence in the distribution of the affected retina and vision is significantly compromised in over 50% of patients who have either chronic macular oedema or ischemia involving the...

  6. Recursive algorithms, branching coefficients and applications

    CERN Document Server

    Lyakhovsky, Vladimir

    2010-01-01

    Recurrent relations for branching coefficients in affine Lie algebras integrable highest weight modules are studied. The decomposition algorithm based on the injection fan technique is adopted to the situation where the Weyl denominator becomes singular with respect to a reductive subalgebra. We study some modifications of the injection fan technique and demonstrate that it is possible to define the "subtracted fans" that play the role similar to the original ones. Possible applications of subtracted fans in CFT models are considered.

  7. Synthesis and Properties of Dendritic Long-Chain Esters as Crude Oil Flow Improver Additives

    Institute of Scientific and Technical Information of China (English)

    Li Cuiqin; Sun Peng; Shi Weiguang; Wang Jun

    2016-01-01

    The efifciencies of 6 kinds of macromolecules with dendritic structure in improving the lfow properties of crude oil were investigated. The dendritic additives were synthesized using low-generation dendritic poly(amidoamine) and alkyl long-chain acrylic esters as starting materials, and their structures were characterized by the Fourier transform infrared spectroscopy, 1H-nuclear magnetic resonance and elemental analysis. The effects on the pour point and rheological properties of crude oil samples were studied. Efifciencies of dendritic long-chain esters were not only inlfuenced by the alky chain length, but also by the generation of dendrimer. The longer the alkyl chain of dendritic long-chain ester was, the better the effect in the reduction of pour point and apparent viscosity was. Efifciencies of 1.5 generation dendritic long-chain ester with 8 branched chains for the reduction of pour point and apparent viscosity were superior to those of 0.5 generation dendritic long-chain ester with 4 branched chains. Under the same conditions, efifciencies of 1.5 generation dendritic eighteen ester were superior to those of other 1.5 generation dendritic long-chain esters for the reduction of pour point and viscosity of crude oil.

  8. [Geometry and algebra of branches of the middle cerebral artery].

    Science.gov (United States)

    Blinkov, S M

    1986-01-01

    A classification of the cortical branches of the middle cerebral artery (MCA) is suggested by means of which each branch in any hemisphere can be qualified and identified in any variant of MCA branching. The principle of the classification consists in grouping the branches into arteries and trunks of the second, third, etc. order. Branches supplying blood to a certain sector of the lateral surface of the hemisphere are designated arteries. Their number and zone of branching are constant. Branches giving rise to 2 and more arteries are named trunks. Branching of the trunks, the number of trunks of the second, third, etc. order, and the site and type of origin of the arteries are extremely variable. Each trunk can be designated by a formula stating its order and the name of the artery supplied by this trunk. The arrangement of the MCA branches on the surface of the gyri and deep in the sulci, represented on the map of the lateral surface of the hemisphere, is designated conditionally as geometry of MCA branches. The order of branching of the trunks and the type of origin of the arteries, represented on abstract maps of the lateral surface of the hemisphere, are designated conditionally as algebra of the MCA branches. The variability of the geometry and algebra of the MCA branches must be taken into consideration in operations for extra-intracranial microanastomosis and in endovasal intervention on the MCA. PMID:3811741

  9. Measurements of $\\Xi_c^{+}$ Branching Ratios

    CERN Document Server

    Link, J M; Anjos, J C; Bediaga, I; Göbel, C; Magnin, J; Massafferri, A; De Miranda, J M; Pepe, I M; Polycarpo, E; Dos Reis, A C; Carrillo, S; Casimiro, E; Cuautle, E; Sánchez-Hernández, A; Uribe, C; Vázquez, F; Agostino, L; Cinquini, L; Cumalat, J P; O'Reilly, B; Segoni, I; Wahl, M; Butler, J N; Cheung, H W K; Chiodini, G; Gaines, I; Garbincius, P H; Garren, L A; Gottschalk, E E; Kasper, P H; Kreymer, A E; Kutschke, R; Wang, M; Benussi, L; Bertani, M; Bianco, S; Fabbri, Franco Luigi; Zallo, A; Reyes, M; Cawlfield, C; Kim, D Y; Rahimi, A; Wiss, J; Gardner, R; Kryemadhi, A; Chung, Y S; Kang, J S; Ko, B R; Kwak, J W; Lee, K B; Cho, K; Park, H; Alimonti, G; Barberis, S; Boschini, M; Cerutti, A; D'Angelo, P; Di Corato, M; Dini, P; Edera, L; Erba, S; Giammarchi, M; Inzani, P; Leveraro, F; Malvezzi, S; Menasce, D; Mezzadri, M; Moroni, L; Pedrini, D; Pontoglio, C; Prelz, F; Rovere, M; Sala, S; Davenport, T F; Arena, V; Boca, G; Bonomi, G; Gianini, G; Liguori, G; Lopes-Pegna, D; Merlo, M M; Pantea, D; Ratti, S P; Riccardi, C; Vitulo, P; Hernández, H; López, A M; Luiggi, E; Méndez, H; Paris, A; Quinones, J; Ramírez, J E; Zhang, Y; Wilson, J R; Handler, T; Mitchell, R; Engh, D; Hosack, M; Johns, W E; Nehring, M S; Sheldon, P D; Stenson, K; Vaandering, E W; Webster, M; Sheaff, M

    2003-01-01

    Using data collected by the fixed target Fermilab experiment FOCUS, we measure the branching ratios of the Cabibbo favored decays $\\Xi_c^+ \\to \\Sigma^+K^-\\pi^+$, $\\Xi_c^+ \\to \\Sigma^+ \\bar{K}^{*}(892)^0$, and $\\Xi_c^+ \\to \\Lambda^0K^-\\pi^+\\pi^+$ relative to $\\Xi_c^+ \\to \\Xi^-\\pi^+\\pi^+$ to be $0.91\\pm0.11\\pm0.04$, $0.78\\pm0.16\\pm0.06$, and $0.28\\pm0.06\\pm0.06$, respectively. We report the first observation of the Cabibbo suppressed decay $\\Xi_c^+ \\to \\Sigma^+K^+K^-$ and we measure the branching ratio relative to $\\Xi_c^+ \\to \\Sigma^+K^-\\pi^+$ to be $0.16\\pm0.06\\pm0.01$. We also set 90% confidence level upper limits for $\\Xi_c^+ \\to \\Sigma^+ \\phi$ and $\\Xi_c^+ \\to \\Xi^*(1690)^0(\\Sigma^+ K^-) K^+$ relative to $\\Xi_c^+ \\to \\Sigma^+K^-\\pi^+$ to be 0.12 and 0.05, respectively. We find an indication of the decays $\\Xi_c^+ \\to \\Omega^-K^{+}\\pi^+$ and $\\Xi_c^+ \\to \\Sigma^{*}(1385)^+ \\bar{K}^0$ and set 90% confidence level upper limits for the branching ratios with respect to $\\Xi_c^+ \\to \\Xi^-\\pi^+\\pi^+$ to be 0.12 a...

  10. Supply Chain Issues in China’s Milk Adulteration Incident

    OpenAIRE

    Gale, H. Frederick, Jr.; HU, Dinghuan

    2009-01-01

    China’s melamine milk adulteration crisis highlights the challenges that arise as large well-capitalized companies procure raw materials from a diffused supply chain of scattered small farmers and milk collection stations. As milk prices climbed sharply in 2007 and companies branched out into new territories, intense competition for raw milk supplies strengthened incentives to water down and adulterate milk. Effective food safety measures must account for incentives, the distribution of marke...

  11. Logistics Performance of Actors in the Wine Supply Chain

    OpenAIRE

    Chandes, Jerôme; Estampe, Dominique

    2003-01-01

    International audience In an environment marked by ever-greater international competition, wine sector companies have been seriously questioning the structure of their entire logistics chain. This is due to the emergence of new actors (i.e., large retailers); the diversification of service providers' product offers; and the different rapprochements between actors in this branch. These are all signals that have caused companies to question their logistics strategies as shown in the ISLI sur...

  12. Understanding the supply chain

    Directory of Open Access Journals (Sweden)

    Aćimović Slobodan

    2006-01-01

    Full Text Available Supply chain management represents new business philosophy and includes strategically positioned and much wider scope of activity in comparison with its "older brother" - management of logistics. Philosophy of the concept of supply chain is directed to more coordination of key business functions of every link in distribution chain in the process of organization of the flow of both goods and information, while logistic managing instruments are focused on internal optimum of flows of goods and information within one company. Applying the concept of integrated supply chain among several companies makes the importance of operative logistics activity even greater on the level of one company, thus advancing processes of optimum and coordination within and between different companies and confirms the importance of logistics performances for the company’s profitability. Besides the fact that the borders between companies are being deleted, this concept of supply chain in one distribution channel influences increasing of importance of functional, i.e. traditional business managing approaches but instead it points out the importance of process managing approaches. Although the author is aware that "there is nothing harder, more dangerous and with uncertain success, but to find a way for introducing some novelties (Machiavelli, it would be even his additional stimulation for trying to bring closer the concept and goals of supply chain implementation that are identified in key, relevant, modern, theoretical and consulting approaches in order to achieve better understanding of the subject and faster implementation of the concept of supply chain management by domestic companies.

  13. Cylindrical polymer brushes with dendritic side chains by iterative anionic reactions

    KAUST Repository

    Zhang, Hefeng

    2015-05-01

    We report in this paper an easy method for the synthesis of cylindrical polymer brushes with dendritic side chains through anionic reaction. The synthesis is accomplished by iteratively grafting a living block copolymer, polyisoprene-. b-polystyrenyllithium (PI-. b-PSLi), to the main chain and subsequently to the branches in a divergent way. PI segment is short and serves as a precursor for multifunctional branching unit. The grafting reaction involves two successive steps: i) epoxidation of internal double bonds of PI segments, either in main chain or side chains; ii) ring-opening addition to the resulting epoxy group by the living PI-. b-PSLi. Repeating the two steps affords a series of cylindrical polymer brushes with up to 3rd generation and extremely high molecular weight. The branching multiplicity depends on the average number of oxirane groups per PI segment, usually ca. 8 in the present work. The high branching multiplicity leads to tremendous increase in molecular weights of the cylindrical products with generation growth. Several series of cylindrical polymer brushes with tunable aspect ratios are prepared using backbones and branches with controlled lengths. Shape anisotropy is investigated in dilute solution using light scattering technique. Worm-like single molecular morphology with large persistence length is observed on different substrates by atomic force microscopy.

  14. Project Decision Chain

    DEFF Research Database (Denmark)

    Rolstadås, Asbjørn; Pinto, Jeffrey K.; Falster, Peter;

    2015-01-01

    To add value to project performance and help obtain project success, a new framework for decision making in projects is defined. It introduces the project decision chain inspired by the supply chain thinking in the manufacturing sector and uses three types of decisions: authorization, selection......, and plan decision. A primitive decision element is defined where all the three decision types can be accommodated. Each task in the primitive element can in itself contain subtasks that in turn will comprise new primitive elements. The primitive elements are nested together in a project decision chain....

  15. Differentiation of crack branching types in fractured glass

    Science.gov (United States)

    Rabinovitch, A.; Bahat, D.

    2011-07-01

    The influence of different physical factors on the fracture branching phenomenon was investigated on a fractured brittle (glass) bottle. A fully branched fracture tree consisting of 144 initiation sites was induced. Branching sites were concentrated in two zones: close to the fracture origin and further away from it along the bottle axis, which was shown to be related to reflection of transverse acoustic waves from the bottle's shoulder. Two types of branching formed, complete full branches (FB), and attempted branching (AB) when one branch was shorter than 5 mm. Branching in the first zone was shown to be regulated by both the distribution of flaw lengths and the distances from each FB to its nearest fracture neighbor. Fracture spacing was found to be proportional to the stress at the propagating fracture tips.

  16. Evaluation of allowable external pressure for branch pipe connections

    International Nuclear Information System (INIS)

    Although the allowable external pressure for branch pipe connections is estimated by evaluation procedure for straight pipe, the applicability of this procedure has not been clear. That was discussed in this study. The buckling pressure of branch pipe connections was estimated by linear eigenvalue analysis with FEA (Finite Element Analysis). The types of branch pipe connections were T-joints and T-pipes. The ranges of configurations in branch pipe connections for FEA were determined by survey of branch pipe connections in the Japanese nuclear power plants. The results of the FEA showed that the buckling strength of branch pipe was found sufficiently to be superior to that of straight piping from comparisons of estimations by FEA for branch pipe connections and those by formula for straight pipe in the design code. It was concluded that the formula for straight pipe is applicable for the evaluation of allowable external pressure for branch pipe connections. (author)

  17. Calcium as a branching signal in Neurospora crassa.

    OpenAIRE

    Reissig, J L; Kinney, S G

    1983-01-01

    The divalent cation ionophore A23187 was found to induce apical branching in Neurospora crassa. Optimal effects were obtained by treatment with 0.1 mM ionophore for 30 min. Branching first became manifest during or shortly after treatment; successive rounds of branching could be observed at later times. Calcium starvation of the mycelium markedly reduced its subsequent response to the ionophore, whereas starvation for other divalent cations had no detectable effect. The branching response was...

  18. Characterizing Weighted MSO for Trees by Branching Transitive Closure Logics

    OpenAIRE

    Fülöp, Zoltán; Vogler, Heiko

    2012-01-01

    We introduce the branching transitive closure operator on weighted monadic second-order logic formulas where the branching corresponds in a natural way to the branching inherent in trees. For arbitrary commutative semirings, we prove that weighted monadic second order logics on trees is equivalent to the definability by formulas which start with one of the following operators: (i) a branching transitive closure or (ii) an existential second-order quantifier followed by one universal first-ord...

  19. Statistics of branched flow in a weak correlated random potential

    OpenAIRE

    Kaplan, Lev

    2002-01-01

    Recent images of electron flow through a two-dimensional electron gas (2DEG) device show branching behavior that is reproduced in numerical simulations of motion in a correlated random potential [cond-mat/0010348]. We show how such branching naturally arises from caustics in the classical flow and find a simple scaling behavior of the branching under variation of the random potential strength. Analytic results describing the statistical properties of the branching are confirmed by classical a...

  20. Identification and carbon isotope composition of a novel branched GDGT isomer in lake sediments: Evidence for lacustrine branched GDGT production

    Science.gov (United States)

    Weber, Yuki; De Jonge, Cindy; Rijpstra, W. Irene C.; Hopmans, Ellen C.; Stadnitskaia, Alina; Schubert, Carsten J.; Lehmann, Moritz F.; Sinninghe Damsté, Jaap S.; Niemann, Helge

    2015-04-01

    Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are bacterial membrane lipids that occur ubiquitously in soils and lacustrine sediments and have great potential as proxy indicators for paleotemperature and pH reconstructions. Initially, brGDGTs in lakes were thought to originate from soils of the watershed. The composition of the lacustrine brGDGT pool, however, often differs substantially from that in catchment soils, complicating the application of the brGDGT paleothermometer to lake sediments. This suggests that terrigenous brGDGT signals in lacustrine sedimentary archives may be affected by aquatic in situ production. In sediments of a Swiss mountain lake, we detected a novel hexamethylated brGDGT, which elutes between the known 5- and 6-methyl brGDGT isomers during HPLC-MS analysis. This novel isomer accounted for 8.5% of the total brGDGTs. Most remarkably, this brGDGT was not detected in soils collected from the catchment of the lake, providing circumstantial evidence for an in situ brGDGT source in the lake's water column or sediments. Isolation of the compound by preparative HPLC and subsequent GC-MS analysis of the alkyl chains revealed that the novel brGDGT comprises two structural isomers. One possesses a 5,13,16- and a 6,13,16-trimethyloctacosanyl moiety and constitutes 84% of the new brGDGT; the second contains a 13,16-dimethyloctacosanyl and a 5,13,16,23-tetramethyloctacosanyl moiety. The δ13C values of both the alkyl chains derived from the novel brGDGT (-46‰) and all other major brGDGTs (-43‰ to -44‰) were significantly lower than those of brGDGT-derived alkanes in catchment soils (-27‰ to -28‰) further attesting to in situ production of brGDGTs in the studied lake.

  1. Editorial: Supply Chain Management

    Directory of Open Access Journals (Sweden)

    Aidonis, D.

    2012-01-01

    Full Text Available This special issue has followed up the 2nd Olympus International Conference on Supply Chains held on October 5-6, 2012, in Katerini, Greece. The Conference was organized by the Department of Logistics of Alexander Technological Educational Institution (ATEI of Thessaloniki, in collaboration with the Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH. During the 2-Days Conference more than 50 research papers were presented covering the following thematic areas: (i Business Logistics, (ii Transportation, Telematics and Distribution Networks, (iii Green Logistics, (iv Information and Communication Technologies in Supply Chain Management, and (v Services and Quality. Three keynote invited speakers addressed interesting issues for the Humanitarian Logistics, Green Supply Chains of the Agrifood Sector and the Opportunities and Prospects of Greek Ports chaired Round Tables with other Greek and Foreign Scientists and Specialists.

  2. Supply chain risk management

    Directory of Open Access Journals (Sweden)

    Christian Hollstein

    2013-03-01

    Full Text Available Background: Supply chain risk management increasingly gains prominence in many international industries. In order to strengthen supply chain structures, processes, and networks, adequate potentials for risk management need to be built (focus on effective logistics and to be utilized (focus on efficient logistics. Natural-based disasters, such as the case of Fukushima, illustrate how crucial risk management is. Method: By aligning a theoretical-conceptual framework with empirical-inductive findings, it may be hypothesized that logistical systems do have a positive effect on supply chain risk management activities.  Result/conclusion:  Flexibility and capacity, as well as redundancy and standardization, are often viewed as being conflictionary. It shows, however, that in the light of supply chain risk management, those factors may yield a common benefit if proper logistics systems are applied.  

  3. Theoretical prediction of side branch compromise after main branch stenting in coronary bifurcation

    Institute of Scientific and Technical Information of China (English)

    Dobrin Vassilev; Robert Gil

    2008-01-01

    One of the main problems of treatment of bifurcation lesions is side branch (SB) stenosis appearing after stent placement in the main vessel.The aim of this study was to create quantitative method for prediction of side branch compromise extent.We accepted that the main mechanism for SB ostial stenosis is flow divider (FD) displacement from stent struts after stent implantation in the main vessel.Using easily measurable parameters from coronary angiography,as SB diameter,angle α (initial angle between axes of parent vessel and SB axis) and angle α' (angle between above mentioned axes after stent placement) we can calculate percentage diameter stenosis at branch ostium (%DS):%DS = sin (α - α')/(tan α).In boundary condition of full FD displacement %DS = cos α.We tested our theoretical predictions with fluoroscopic observation of elastic wall model of bifurcation (45°distal angle between branches)permitting wall deformations with stent.There is full coincidence of values of %DS and percentage area stenosis (%AS).The regular formulas for calculations of %DS and %AS overestimate stenosis severity between 10% and 25%.Our model tests have shown full coincidence between predicted values for %DS and observed values.We demonstrate that part of the SB ostium is not visible in regular angiography and contributes to ostial lumen area.This is a method that permits quantitative prediction of side branch compromise.

  4. 40 CFR 721.10094 - Decene, branched and linear.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Decene, branched and linear. 721.10094... Substances § 721.10094 Decene, branched and linear. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as decene, branched and linear (PMN P-03-272;...

  5. Catalytic production of branched small alkanes from biohydrocarbons.

    Science.gov (United States)

    Oya, Shin-ichi; Kanno, Daisuke; Watanabe, Hideo; Tamura, Masazumi; Nakagawa, Yoshinao; Tomishige, Keiichi

    2015-08-10

    Squalane, C30 algae-derived branched hydrocarbon, was successfully converted to smaller hydrocarbons without skeletal isomerization and aromatization over ruthenium on ceria (Ru/CeO2 ). The internal CH2 CH2 bonds located between branches are preferably dissociated to give branched alkanes with very simple distribution as compared with conventional methods using metal-acid bifunctional catalysts.

  6. Structural dynamics branch research and accomplishments to FY 1992

    Science.gov (United States)

    Lawrence, Charles

    1992-12-01

    This publication contains a collection of fiscal year 1992 research highlights from the Structural Dynamics Branch at NASA LeRC. Highlights from the branch's major work areas--Aeroelasticity, Vibration Control, Dynamic Systems, and Computational Structural Methods are included in the report as well as a listing of the fiscal year 1992 branch publications.

  7. Supply chain reliability modelling

    OpenAIRE

    Eugen Zaitsev

    2012-01-01

    Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the ...

  8. Supply Chain Collaboration

    OpenAIRE

    Guy Rodrigue Ghomsi 1982

    2015-01-01

    Companies are now progressively looking beyond themselves to come up with ways to improve revenue and profit margins. This has resulted in a heightened focus on the efficiency of the supply chains. Inefficient supply chains are being perceived as cavities that can deprive the firm from its cash flows when inventory is not required and sales revenue when product is not available at the point of sales. This has stimulated development of business models that intend to leverage and enhance the su...

  9. Variance bounding Markov chains

    OpenAIRE

    Roberts, Gareth O.; Jeffrey S. Rosenthal

    2008-01-01

    We introduce a new property of Markov chains, called variance bounding. We prove that, for reversible chains at least, variance bounding is weaker than, but closely related to, geometric ergodicity. Furthermore, variance bounding is equivalent to the existence of usual central limit theorems for all L2 functionals. Also, variance bounding (unlike geometric ergodicity) is preserved under the Peskun order. We close with some applications to Metropolis–Hastings algorithms.

  10. Supply chain risk management

    OpenAIRE

    Christian Hollstein; Frank Himpel

    2013-01-01

    Background: Supply chain risk management increasingly gains prominence in many international industries. In order to strengthen supply chain structures, processes, and networks, adequate potentials for risk management need to be built (focus on effective logistics) and to be utilized (focus on efficient logistics). Natural-based disasters, such as the case of Fukushima, illustrate how crucial risk management is. Method: By aligning a theoretical-conceptual framework with empirical-induct...

  11. Editorial: Supply Chain Management

    OpenAIRE

    Aidonis, D.; Folinas, D.; Triantafillou, D.

    2012-01-01

    This special issue has followed up the 2nd Olympus International Conference on Supply Chains held on October 5-6, 2012, in Katerini, Greece. The Conference was organized by the Department of Logistics of Alexander Technological Educational Institution (ATEI) of Thessaloniki, in collaboration with the Laboratory of Quantitative Analysis, Logistics and Supply Chain Management of the Department of Mechanical Engineering, Aristotle University of Thessaloniki (AUTH). During the 2-Days Conference m...

  12. Innovation Across the Supply Chain

    DEFF Research Database (Denmark)

    Druehl, Cheryl; Carrillo, Janice; Hsuan, Juliana

    Innovation is an integral part of every firm’s ongoing operations. Beyond product innovation, supply chain innovations offer a unique source of competitive advantage. We synthesize recent research on innovation in the supply chain, specifically, innovative supply chain processes...

  13. MASTERING SUPPLY CHAIN RISKS

    Directory of Open Access Journals (Sweden)

    Borut Jereb

    2012-11-01

    Full Text Available Risks in supply chains represent one of the major business issues today. Since every organizationstrives for success and uninterrupted operations, efficient supply chain risk management is crucial.During supply chain risk research at the Faculty of Logistics in Maribor (Slovenia some keyissues in the field were identified, the major being the lack of instruments which can make riskmanagement in an organization easier and more efficient. Consequently, a model which captures anddescribes risks in an organization and its supply chain was developed. It is in accordance with thegeneral risk management and supply chain security standards, the ISO 31000 and ISO 28000families. It also incorporates recent finding from the risk management field, especially from theviewpoint of segmenting of the public.The model described in this paper focuses on the risks itself by defining them by different keydimensions, so that risk management is simplified and can be undertaken in every supply chain andorganizations within them. Based on our mode and consequent practical research in actualorganizations, a freely accessible risk catalog has been assembled and published online from the risksthat have been identified so far. This catalog can serve as a checklist and a starting point in supplychain risk management in organizations. It also incorporates experts from the field into a community,in order to assemble an ever growing list of possible risks and to provide insight into the model andits value in practice.

  14. Issues on Supply Chain Management

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Although supply chain is regarded as an integrated pr ocess, actually, researchers and practitioners have primarily investigated the v arious processes of the supply chain individually. The competitive field in most markets requires well-designed integrated supply chain instead of individual o perations. In this paper, some traditional thinking of supply chain is given fir st, then SCM (Supply Chain Management) is introduced, which views the entire sup ply chain as a whole rather than individual process a...

  15. Branched Crystalline Patterns of Poly(ε-caprolactone) and Poly(4-hydroxystyrene) Blends Thin Films.

    Science.gov (United States)

    Hou, Chunyue; Yang, Tianbo; Sun, Xiaoli; Ren, Zhongjie; Li, Huihui; Yan, Shouke

    2016-01-14

    The chain organization of poly(ε-caprolactone) (PCL) in its blend with poly(4-hydroxystyrene) (PVPh) in thin films (130 ± 10 nm) has been revealed by grazing incident infrared (GIIR) spectroscopy. It can be found that PCL chains orient preferentially in the surface-normal direction and crystallization occurs simultaneously. The morphology of the PCL/PVPh blends films can be identified by optical microscopy (OM). When crystallized at 35 °C, the blends film shows a seaweed-like structure and becomes more open with increasing PVPh content. In contrast, when crystallized at higher temperatures, i.e., 40 and 45 °C, dendrites with apparent crystallographically favored branches can be observed. This characteristic morphology indicates that the diffusion-limited aggregation (DLA) process controls the crystal growth in the blends films. The detailed lamellar structure can be revealed by the height images of atomic force microscopy (AFM), i.e., the crystalline branches are composed of overlayered flat-on lamellae. The branch width has been found to be dependent on the supercooling and PVPh content. This result differs greatly from pure PCL, in which case the crystal patterns controlled by DLA process developed in ultrathin film or monolayers of several nanometers. In the PCL/PVPh blends case, the strong intermolecular interactions and the dilution effect of PVPh should contribute to these results. That is to say, the mobility of PCL chains can be retarded and diffusion of them to the crystal growth front slows down greatly, even though the film thickness is far more than the lamellar thickness of PCL. PMID:26713897

  16. Geology of the Cane Branch and Helton Branch watershed areas, McCreary County, Kentucky

    Science.gov (United States)

    Lyons, Erwin J.

    1957-01-01

    Cane Branch and Helton Branch in McCreary County, Kentucky, are about 1.4 miles apart (fig. 1). Can Branch, which is about 2.1 miles long, emptied into Hughes Fork of Beaver Creek. Its watershed area of about 1.5 square miles lies largely in the Wiborf 7 1/2-minute quadrangle (SW/4 Cumberland Falls 15-minute quadrangle), but the downstream part of the area extends northward into the Hail 7 1/2-minute quadrangle (NW/4 Cumberland Falls 15-minute quadrangle). Helton Branch, which is about 1.1 miles long, has two tributaries and empties into Little Hurricane Fork of Beaver Creek. It drains an area of about 0.8 square mile of while about 0.5 square mile is in the Hail quadrangle and the remainder in the Wilborg quadrangle. The total relief in the Can Branch area is about 500 feet and in the Helton Branch area about 400 feet. Narrow, steep-sided to canyon-like valley and winding ridges, typical of the Pottsville escarpment region, are characteristic of both areas. Thick woods and dense undergrowth cover much of the two areas. Field mapping was done on U.S. Geological Survey 7 1/2-minute maps having a scale of 1:24,000 and a contour interval of 20 feet. Elevations of lithologic contacts were determined with a barometer and a hand level. Aerial photographs were used principally to trace the cliffs formed by sandstone and conglomerate ledges. Exposures, except for those of the cliff- and ledge-forming sandstone and conglomerates, are not abundant. The most complete stratigraphic sections (secs. 3 and 4, fig. 2) in the two areas are exposed in cuts of newly completed Forest Service roads, but the rick in the upper parts of the exposures is weathered. To supplement these sections, additional sections were measured in cuts along the railroad and main highways in nor near the watersheds.

  17. Organization and targets of the European Branch

    Energy Technology Data Exchange (ETDEWEB)

    Cataldi, R.

    1997-12-01

    After a short historical review of the formation, objectives and organization of the International Geothermal Association (IGA), this paper describes the functions, goals and activities of the IGA European Branch. In particular, the paper illustrates the plan of action established for the periods 1993-`95 and 1996-`98, and the issues dealt with by the European Forum as of August 1996. The last section of the paper outlines the main problems to be faced in the near future in order to facilitate the aggregation of efforts, the amalgamation of promotional initiatives and the coordination of the basic activities needed for the consolidation and growth of the geothermal community in Europe. (orig.)

  18. Branching of periodic orbits from Kukles isochrones

    Directory of Open Access Journals (Sweden)

    B. Toni

    1998-05-01

    Full Text Available We study local bifurcations of limit cycles from isochronous (or linearizable centers. The isochronicity has been determined using the method of Darboux linearization, which provides a birational linearization for the examples that we analyze. This transformation simplifies the analysis by avoiding the complexity of the Abelian integrals appearing in other approaches. As an application of this approach, we show that the Kukles isochrone (linear and nonlinear has at most one branch point of limit cycles. Moreover, for each isochrone, there are small perturbations with exactly one continuous family of limit cycles.

  19. Annual report, Basic Sciences Branch, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-01

    This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1990, through September 30, 1991. Seven technical sections of the report cover these main areas of NREL's in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, Solid-State Spectroscopy, and Superconductivity. Each section explains the purpose and major accomplishments of the work in the context of the US Department of Energy's National Photovoltaic Research Program plans.

  20. Branch Processes of Regular Magnetic Monopole

    Institute of Scientific and Technical Information of China (English)

    MO Shu-Fan; REN Ji-Rong; ZHU Tao

    2009-01-01

    In this paper, by making use of Duan's topological current theory, the branch process of regular magnetic monopoles is discussed in detail Regular magnetic monopoles are found generating or annihilating at the limit point and encountering, splitting, or merging at the bifurcation point and the degenerate point systematically of the vector order parameter field φ(x).Furthermore, it is also shown that when regular magnetic monopoles split or merge at the degenerate point of field function φ, the total topological charges of the regular magnetic monopoles axe still unchanged.

  1. Annual report, Materials Science Branch, FY 1992

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, S. [ed.

    1993-10-01

    This report summarizes the progress of the Materials Science Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1991, through September 30, 1992. Six technical sections of the report cover these main areas of NREL`s in-house research: Crystal Growth, Amorphous Silicon, III-V High-Efficiency Photovoltaic Cells, Solid State Theory, Solid State Spectroscopy, and Program Management. Each section explains the purpose and major accomplishments of the work in the context of the US Department of Energy`s National Photovoltaic Research Program plans.

  2. Annual report, Basic Sciences Branch, FY 1991

    Energy Technology Data Exchange (ETDEWEB)

    1993-04-01

    This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1990, through September 30, 1991. Seven technical sections of the report cover these main areas of NREL`s in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, Solid-State Spectroscopy, and Superconductivity. Each section explains the purpose and major accomplishments of the work in the context of the US Department of Energy`s National Photovoltaic Research Program plans.

  3. Logic, planning agency and branching time

    OpenAIRE

    Ricardo Souza Silvestre

    2010-01-01

    The purpose of this paper is to give a formal account of a kind of agency so far neglected in the field of philosophical modal logic of action: planning agency. In doing this we follow the standard approach of modal logics of agency exemplified by the works of Belnap, Chellas and Pörn. Since we believe there is a close relation between planning, time and indeterminism, we use the theory of branching time as a conceptual framework for investigating the basic features of planning agency. Beside...

  4. Strategy of Irrigation Branch in Russia

    Science.gov (United States)

    Zeyliger, A.; Ermolaeva, O.

    2012-04-01

    At this moment, at the starting time of the program on restoration of a large irrigation in Russia till 2020, the scientific and technical community of irrigation branch does not have clear vision on how to promote a development of irrigated agriculture and without repeating of mistakes having a place in the past. In many respects absence of a vision is connected to serious backlog of a scientific and technical and informational and technological level of development of domestic irrigation branch from advanced one. Namely such level of development is necessary for the resolving of new problems in new conditions of managing, and also for adequate answers to new challenges from climate and degradation of ground & water resources, as well as a rigorous requirement from an environment. In such important situation for irrigation branch when it is necessary quickly generate a scientific and technical politics for the current decade for maintenance of translation of irrigated agriculture in the Russian Federation on a new highly effective level of development, in our opinion, it is required to carry out open discussion of needs and requirements as well as a research for a adequate solutions. From political point of view a framework organized in FP6 DESIRE 037046 project is an example of good practice that can serve as methodical approach how to organize and develop such processes. From technical point of view a technology of operational management of irrigation at large scale presents a prospective alternative to the current type of management based on planning. From point of view ICT operational management demands creation of a new platform for the professional environment of activity. This platform should allow to perceive processes in real time, at their partial predictability on signals of a straight line and a feedback, within the framework of variability of decision making scenarious, at high resolution and the big ex-awning of sensor controls and the gauges

  5. Accelerator Physics Branch annual technical report, 1989

    International Nuclear Information System (INIS)

    The report describes, in a series of separate articles, the achievements of the Accelerator Physics Branch for the calendar year 1989. Work in basic problems of accelerator physics including ion sources, high-duty-factor rf quadrupoles, coupling effects in standing wave linacs and laser acceleration is outlined. A proposal for a synchrotron light source for Canada is described. Other articles cover the principal design features of the IMPELA industrial electron linac prototype, the cavities developed for the HERA complex at DESY, Hamburg, West Germany, and further machine projects that have been completed

  6. Structure of branching enzyme- and amylomaltase modified starch produced from well-defined amylose to amylopectin substrates

    DEFF Research Database (Denmark)

    Sorndecha, Waraporn; Sagnelli, Domenico; Meier, Sebastian;

    2016-01-01

    Thermostable branching enzyme (BE, EC 2.4.1.18) from Rhodothermus obamensis in combination with amylomaltase (AM, EC 2.4.1.25) from Thermus thermophilus was used to modify starch structure exploring potentials to extensively increase the number of branch points in starch. Amylose is an important...... constituent in starch and the effect of amylose on enzyme catalysis was investigated using amylose-only barley starch (AO) and waxy maize starch (WX) in well-defined ratios. All products were analysed for amylopectin chain length distribution, α-1,6 glucosidic linkages content, molar mass distribution...... and digestibility by using rat intestinal α-glucosidases. For each enzyme treatment series, increased AO content resulted in a higher rate of α-1,6 glucosidic linkage formation but as an effect of the very low initial branching of the AO, the final content of α-1,6 glucosidic linkages was slightly lower as compared...

  7. Optimizing energy transfer efficiency in highly branched nanoplasmonic waveguides

    Science.gov (United States)

    Voronine, Dmitri; Traverso, Andrew; Wang, Kai; Yi, Zhenhuan; Sokolov, Alexei

    2011-03-01

    Energy transfer in highly branched nanoplasmonic particle waveguides is simulated and optimized by varying the waveguide branching geometry and composition. The periodically branched nanostructures provide a new route towards efficient nanoscale light concentration and local field enhancement. On the one hand, they mimick the analogous randomly branched plasmonic nanostructures which have been previously used for surface-enhanced optical spectroscopy such as SERS. On the other hand, the design is inspired by branched molecular aggregates used for energy funneling. The proposed nanostructures may find applications in sensing, light harvesting and nanophotonics.

  8. A dynamical-system picture of a simple branching-process phase transition

    CERN Document Server

    Williams, David

    2010-01-01

    This paper develops ideas from a previous paper described as `an appetizer for non-linear Wiener--Hopf theory', but is completely independent of that paper. It again considers only the simplest possible case in which the underlying motion of the branching particles is described by a two-state Markov chain. Key generating functions provide solutions of a simple two-dimensional dynamical system, and the main interest is in the way in which Probability Theory and ODE theory complement each other. ODE pictures convey rather strikingly a simple phase transition. No knowledge of either ODE theory or Wiener--Hopf theory is assumed.

  9. Creep measurements confirm steady flow after stress maximum in extension of branched polymer melts

    DEFF Research Database (Denmark)

    Javier Alvarez, Nicolas; Román Marín, José Manuel; Huang, Qian;

    2013-01-01

    We provide conclusive evidence of nonmonotonic mechanical behavior in the extension of long-chain branched polymer melts. While nonmonotonic behavior is known to occur for solids, for the case of polymeric melts, this phenomenon is in direct contrast with current theoretical models. We rule out...... the possibility of the overshoot being an experimental artifact by confirming the existence of steady flow after a maximum in the ratio of stress to strain rate versus strain under both constant stress and constant strain-rate kinematics. This observation indicates the omission of important physics from current...

  10. Chain and Ion Dynamics in Ionomer Melts

    Science.gov (United States)

    Register, Richard A.

    2003-03-01

    Ionomers contain a minor quantity of covalently-bound ionic sites, such as carboxylic or sulfonic acid salts, typically distributed randomly along the polymer backbone. Associations between these ionic groups greatly increase the melt viscosity and elasticity through the formation of a reversible network, where the ionic crosslinks gradually relax by a ``hopping" of ionic groups between aggregates. Because terminal relaxation of the chain requires an accumulation of many hops, the time scales for ion and chain motion differ by several orders of magnitude, so we employ mechanical rheometry to probe chain motion, and gauge ion motion through cation diffusion, by annealing for a preset interval and measuring the cation concentration profile through electron probe microanalysis or electron spin resonance spectroscopy. We have investigated both ethylene-methacrylic acid (E/MAA) ionomers, with a broad molecular weight distribution and substantial long-chain branching, as well as new linear-chain ionomers of narrow distribution based on lightly-sulfonated styrene-ethylene-butene (SSEB) terpolymers. Our E/MAA results support the ion-hopping mechanism, with similarly-large activation energies for terminal relaxation and cation diffusion. The choice of neutralizing metal cation has only a modest effect on the dynamics, though the terminal time increases exponentially with neutralization level. Unneutralized acid groups can accelerate the ion-hopping process by "plasticizing" the ionic aggregates. The model SSEB ionomers, which are noncrystallizable and have a low Tg, permit measurements over a much wider range of effective frequencies and are found to deviate substantially from time-temperature superposition, because the outermost portions of the polymer chains, which contain no ionic groups, relax with a smaller activation energy. Relaxation of these chain segments leads to a dilution of the entanglement network, and a plateau modulus below that for highly

  11. A 2-chain can interlock with a k-chain

    OpenAIRE

    Glass, Julie; Langerman, Stefan; O'Rourke, Joseph; Snoeyink, Jack; Zhong, Jianyuan K.

    2004-01-01

    One of the open problems posed in [3] is: what is the minimal number k such that an open, flexible k-chain can interlock with a flexible 2-chain? In this paper, we establish the assumption behind this problem, that there is indeed some k that achieves interlocking. We prove that a flexible 2-chain can interlock with a flexible, open 16-chain.

  12. Synthesis of branched naphthoquinones from castor oil

    Directory of Open Access Journals (Sweden)

    Adriano Olímpio da Silva

    2012-06-01

    Full Text Available The naphthoquinones are cyclic aromatic α,β-dienonas with a basic framework derived from naphthalene. They are also found in many higher plants, algae, fungi and as the product of the  metabolism  of some  bacteria  having large biologica activity described in the literature such as antibacterial, anti-inflammatory, antitumor, anticancer and trypanocidal [1-3]. Castor oil is an abundant raw material in Brazil of great versatility and, it is present in biodiesel production, surfactants, cosmetics and others. Considering the importance of naphthoquinones and, the availability of the ricinoleic acid from castor oil, the aim of this study was the preparation of new branched naphthoquinones in order to test their trypanocidal activity. Castor oil was submitted to saponification with sodium hydroxide, ethanol and water under reflux for 6 h. We then carried out an acid hydrolysis with hydrochloric acid and the formed ricinoleic acid was extracted with ethyl acetate. Following, through Kochi-Anderson addition reaction it was performed the alkylation of a naphthoquinone 1 and 2, using ammonium persulfate, silver nitrate, acetonitrile and water, under heating at 70-80 ° C during 3 h, to give the branched naphthoquinones 4 and 5 (scheme 1. The naphthoquinone 3 will be similarly submitted to this procedure. The naphthoquinones 4 and 5 were purified by column chromatography on sílica gel using hexane as the eluent. The compounds were characterized by mass spectrometry and 1H and 13CNMR spectroscopy.

  13. Branching dynamics of viral information spreading

    Science.gov (United States)

    Iribarren, José Luis; Moro, Esteban

    2011-10-01

    Despite its importance for rumors or innovations propagation, peer-to-peer collaboration, social networking, or marketing, the dynamics of information spreading is not well understood. Since the diffusion depends on the heterogeneous patterns of human behavior and is driven by the participants’ decisions, its propagation dynamics shows surprising properties not explained by traditional epidemic or contagion models. Here we present a detailed analysis of our study of real viral marketing campaigns where tracking the propagation of a controlled message allowed us to analyze the structure and dynamics of a diffusion graph involving over 31 000 individuals. We found that information spreading displays a non-Markovian branching dynamics that can be modeled by a two-step Bellman-Harris branching process that generalizes the static models known in the literature and incorporates the high variability of human behavior. It explains accurately all the features of information propagation under the “tipping point” and can be used for prediction and management of viral information spreading processes.

  14. Analysis of business demography using markov chains : an application to Belgian data

    OpenAIRE

    François Coppens; Fabienne Verduyn

    2009-01-01

    This paper applies the theory of finite Markov chains to analyse the demographic evolution of Belgian enterprises. While other methodologies concentrate on the entry and exit of firms, the Markov approach also analyses migrations between economic sectors. Besides helping to provide a fuller picture of the evolution of the population, Markov chains also enable forecasts of its future composition to be made, as well as the computation of average lifetimes of companies by branch of activity. The...

  15. Analysis of business demography using markov chains: an application to Belgian data

    OpenAIRE

    Coppens, François; Verduyn, Fabienne

    2009-01-01

    This paper applies the theory of finite Markov chains to analyse the demographic evolution of Belgian enterprises. While other methodologies concentrate on the entry and exit of firms, the Markov approach also analyses migrations between economic sectors. Besides helping to provide a fuller picture of the evolution of the population, Markov chains also enable forecasts of its future composition to be made, as well as the computation of average lifetimes of companies by branch of activity. The...

  16. Phasic Triplet Markov Chains.

    Science.gov (United States)

    El Yazid Boudaren, Mohamed; Monfrini, Emmanuel; Pieczynski, Wojciech; Aïssani, Amar

    2014-11-01

    Hidden Markov chains have been shown to be inadequate for data modeling under some complex conditions. In this work, we address the problem of statistical modeling of phenomena involving two heterogeneous system states. Such phenomena may arise in biology or communications, among other fields. Namely, we consider that a sequence of meaningful words is to be searched within a whole observation that also contains arbitrary one-by-one symbols. Moreover, a word may be interrupted at some site to be carried on later. Applying plain hidden Markov chains to such data, while ignoring their specificity, yields unsatisfactory results. The Phasic triplet Markov chain, proposed in this paper, overcomes this difficulty by means of an auxiliary underlying process in accordance with the triplet Markov chains theory. Related Bayesian restoration techniques and parameters estimation procedures according to the new model are then described. Finally, to assess the performance of the proposed model against the conventional hidden Markov chain model, experiments are conducted on synthetic and real data. PMID:26353069

  17. A 2-chain can interlock with an open 10-chain

    OpenAIRE

    Lu, Bin; O'Rourke, Joseph; Zhong, Jianyuan K.

    2013-01-01

    It is an open problem, posed in \\cite{SoCG}, to determine the minimal $k$ such that an open flexible $k$-chain can interlock with a flexible 2-chain. It was first established in \\cite{GLOSZ} that there is an open 16-chain in a trapezoid frame that achieves interlocking. This was subsequently improved in \\cite{GLOZ} to establish interlocking between a 2-chain and an open 11-chain. Here we improve that result once more, establishing interlocking between a 2-chain and a 10-chain. We present argu...

  18. Cravity modulation of the moss Tortula modica branching

    Science.gov (United States)

    Khorkavtsiv, Yaroslava; Kit, Nadja

    Among various abiotic factors the sensor system of plants constantly perceives light and gravitation impulses and reacts on their action by photo- and gravitropisms. Tropisms play fundamental part in ontogenesis and determination of plant forms. Essentially important question is how light initiating phototropic bending modulates gravitropism. In contrast to flower plants, red light is phototropically active for mosses, and phytochromic system controls initiation of apical growth, branching and photomorphogenesis of mosses. The aim of this investigation was to analyse cell branching of protonemata Tortula modica Zander depending on the direction of light and gravitation vector. The influence of light and gravitation on the form of protonemal turf T. modica, branching and the angle of lateral branches relative to axis of mother cell growth has been investigated. As moss protonemata is not branched in the darkness, light is necessary for branching activation. Minimally low intensity of the red light (0.2 mmol (.) m (-2) ({) .}sec (-1) ) induced branching without visual display of phototropic growth. It has been established that unidirectional action of light and gravitation intensifies branching, and, on the contrary, perpendicularly oriented vectors of factors weaken branches formation. Besides, parallel oriented vectors initiated branching from both cell sides, but oppositely directed vectors initiated branching only from one side. Clinostate rotation the change of the vector gravity and causes uniform cell branching, hence, light and gravitation mutually influence the branching system form of the protonemata cell. It has been shown that the angle of lateral branches in darkness does not depend on the direction of light and gravitation action. After lighting the local growth of the cell wall took place mainly under the angle 90 (o) to the axes of mother cell growth. Then the angle gradually decreased and in 3-4 cell divisions the lateral branch grew under the angle

  19. Modeling of branching density and branching distribution in low-density polyethylene polymerization

    NARCIS (Netherlands)

    D.M. Kim; P.D. Iedema

    2008-01-01

    Low-density polyethylene (ldPE) is a general purpose polymer with various applications. By this reason, many publications can be found on the ldPE polymerization modeling. However, scission reaction and branching distribution are only recently considered in the modeling studies due to difficulties i

  20. POISSON REPRESENTATIONS OF BRANCHING MARKOV AND MEASURE-VALUED BRANCHING PROCESSES

    NARCIS (Netherlands)

    Kurtz, Thomas G.; Rodrigues, Eliane R.

    2011-01-01

    Representations of branching Markov processes and their measure-valued limits in terms of countable systems of particles are constructed for models with spatially varying birth and death rates. Each particle has a location and a "level," but unlike earlier constructions, the levels change with time.

  1. Supply chain quality management

    Directory of Open Access Journals (Sweden)

    Hannan Amoozad Mahdiraji

    2012-10-01

    Full Text Available In recent years, there are several methods introduced for the improvement of operational performances. Total quality management and supply chain management are two methods recommended for this purpose. These two approaches have been studied in most researches separately, while they have objectives in common, and this makes them a strategic means, which can be used, simultaneously. Total quality management and supply chain management play significant roles to increase the organizational competitiveness power. Moreover, they have only one purpose that is customer satisfaction, and they are different only on their approaches to reach their objectives. In this research, we aim to study both approaches of quality management and supply chain, their positive increasing effects that may be generated after their integration. For this purpose, the concept and definitions of each approach is studied, independently, their similarities and differences are recognized, and finally, the advantages of their integration are introduced.

  2. Environmental Retail Supply Chains

    DEFF Research Database (Denmark)

    Kotzab, Herbert; Munch, Hilde; de Faultrier, Birgitte;

    2011-01-01

    been undertaken through an investigative approach applying a web-scan framework which included the analysis of web sites and publicly published documents such as annual reports and corporate social responsibility reports. Findings – The authors identified 34 environmental sustainability initiatives......Purpose – The purpose of this paper is to develop a scale that evaluates the environmental elements in retail supply chains and to examine the environmental supply chain management initiatives of the world's largest 100 retailing companies. Design/methodology/approach – The empirical evaluation has...... which were grouped into eight categories; they refer to “fundamental environmental attitude”, “use of energy”, “use of input material”, “product”, “packaging”, “transport”, “consumption” and “waste”. The level of environmental supply chain management can be characterised as very operational and very...

  3. Supply-Chain Optimization Template

    Science.gov (United States)

    Quiett, William F.; Sealing, Scott L.

    2009-01-01

    The Supply-Chain Optimization Template (SCOT) is an instructional guide for identifying, evaluating, and optimizing (including re-engineering) aerospace- oriented supply chains. The SCOT was derived from the Supply Chain Council s Supply-Chain Operations Reference (SCC SCOR) Model, which is more generic and more oriented toward achieving a competitive advantage in business.

  4. Essentials of supply chain management

    CERN Document Server

    Hugos, Michael H

    2011-01-01

    The latest thinking, strategies, developments, and technologies to stay current in supply chain management Presenting the core concepts and techniques of supply chain management in a clear, concise and easily readable style, the Third Edition of Essentials of Supply Chain Management outlines the most crucial tenets and concepts of supply chain management.

  5. Building the resilient supply chain.

    OpenAIRE

    Christopher, Martin; Peck, Helen

    2004-01-01

    In today’s uncertain and turbulent markets, supply chain vulnerability has become an issue of significance for many companies. As supply chains become more complex as a result of global sourcing and the continued trend to ‘leaning-down’, supply chain risk increases. The challenge to business today is to manage and mitigate that risk through creating more resilient supply chains.

  6. Branched polymers characterized by comprehensive two-dimensional separations with fully orthogonal mechanisms: Molecular-topology fractionation x size-exclusion chromatography

    NARCIS (Netherlands)

    R. Edam; E.P.C. Mes; D.M. Meunier; F.A. van Damme; P.J. Schoenmakers

    2014-01-01

    Polymer separations under non-conventional conditions have been explored to obtain a separation of long-chain branched polymers from linear polymers with identical hydrodynamic size. In separation media with flow-through channels of the same order as the size of the analyte molecules in solution, th

  7. Population balance modeling of full two-dimensional molecular weight and branching distributions for ldPE with topological scission in continuous stirred tank reactor

    NARCIS (Netherlands)

    N. Yaghini; P.D. Iedema

    2015-01-01

    A full extensive 2-dimensional (2D) model of low-density Polyethylene chain length/branching distribution is provided in this paper. 2D Population Balance Equations are solved by the Galerkinfinite element method to obtain the distributions, accounting for 2D 'topological scission'; a manner to appr

  8. METRODOS: Meteorological preprocessor chain

    DEFF Research Database (Denmark)

    Astrup, P.; Mikkelsen, T.; Deme, S.

    2001-01-01

    The METRODOS meteorological preprocessor chain combines measured tower data and coarse grid numerical weather prediction (NWP) data with local scale flow models and similarity scaling to give high resolution approximations of the meteorological situation. Based on available wind velocity...... - heat flux related measurement, e.g. a temperature gradient, are used to give local values of friction velocity and Monin-Obukhov length plus an estimate of the mixing height. The METRODOS meteorological preprocessor chain is an integral part of the RODOS - Real Time On Line Decision Support - program...

  9. Integrated supply chain risk management

    Directory of Open Access Journals (Sweden)

    Riaan Bredell

    2007-11-01

    Full Text Available Integrated supply chain risk management (ISCRM has become indispensable to the theory and practice of supply chain management. The economic and political realities of the modern world require not only a different approach to supply chain management, but also bold steps to secure supply chain performance and sustainable wealth creation. Integrated supply chain risk management provides supply chain organisations with a level of insight into their supply chains yet to be achieved. If correctly applied, this process may optimise management decision-making and assist in the protection and enhancement of shareholder value.

  10. Effect of Chain Extension on Thermal Stability Behaviors of Polylactide Bioplastics

    Directory of Open Access Journals (Sweden)

    Yodthong Baimark

    2016-06-01

    Full Text Available The influences of chain extension and blending temperature on the thermal properties of poly(L-lactide (PLL were investigated. Joncryl® ADR 4368, a styrene-acrylic multifunctional oligomeric agent, was used as a chain extender. Differential scanning calorimetry and thermogravimetry were used to determine the thermal transition properties and thermal stability of the chain extended PLL, respectively. The chain extension reaction occurred at a blending temperature of 190 °C better than at 170 °C. The molecular weights of the chain extended PLLs increased and melt flow indices decreased when the Joncryl® ADR 4368 ratio was increased. The addition of Joncryl® ADR 4368 had an effect on the glass transition temperature, crystallizing temperature and crystallinity of the PLL for the blending temperature of 190 °C. The chain extended PLLs with branched structures showed lower thermal stability than the linear PLLs. The content of branched PLLs increased with the Joncryl® ADR 4368 ratio and blending temperature. The chain extension reaction was complete when 2% Joncryl® ADR 4368 and a blending temperature of 190 °C were used. The results indicated that the chain extension improved the PLL’s melt strength and it has an effect on the thermal stability of the PLLs.

  11. Gauge Theories on the Coulomb branch

    CERN Document Server

    Schwarz, John H

    2014-01-01

    We construct the world-volume action of a probe D3-brane in $AdS_5 \\times S^5$ with $N$ units of flux. It has the field content, symmetries, and dualities of the $U(1)$ factor of ${\\cal N} =4$ $U(N+1)$ super Yang--Mills theory, spontaneously broken to $U(N) \\times U(1)$ by being on the Coulomb branch, with the massive fields integrated out. This motivates the conjecture that it is the exact effective action, called a `highly effective action' (HEA). We construct an $SL(2,Z)$ multiplet of BPS soliton solutions of the D3-brane theory (the conjectured HEA) and show that it reproduces the electrically charged massive states that have been integrated out as well as magnetic monopoles and dyons. Their charges are uniformly spread on a spherical surface, called a `soliton bubble', which is interpreted as a phase boundary.

  12. Multimodal Distributions along the Horizontal Branch

    CERN Document Server

    Ferraro, F R; Pecci, F F; Dorman, B; Rood, R T; Ferraro, Francesco R.; Paltrinieri, Barbara; Pecci, Flavio Fusi; Dorman, Ben; Rood, Robert T.

    1997-01-01

    We report on HST/WFPC2 U,V and far-ultraviolet observations of two Galactic Globular Clusters (GGCs), NGC 6205 = M13 and NGC 6093 = M80. Both of these clusters have horizontal-branch (HB) tails that extend to the helium-burning main sequence, with the hottest stars reaching theoretical effective temperatures above 35,000 K. In both clusters, groups of stars are found to be separated by narrow gaps along the blue HB sequence. These gaps appear at similar locations in the color-magnitude diagrams of the two clusters. While stochastic effects may give rise to variations in the color distribution along the HB, the coincidence of gaps in different clusters effectively rules this out as the primary cause. The comparison among the clusters strongly suggests that there are separate physical processes operating during the earlier red-giant phase of evolution to produce mass loss.

  13. Unquenched flavor on the Higgs branch

    CERN Document Server

    Faedo, Anton F; Pantelidou, Christiana; Tarrio, Javier

    2016-01-01

    We construct the gravity duals of the Higgs branches of three-dimensional (four-dimensional) super Yang-Mills theories coupled to $N_\\textrm{f}$ quark flavors. The effect of the quarks on the color degrees of freedom is included, and corresponds on the gravity side to the backreaction of $N_\\textrm{f}$ flavor D6-branes (D7-branes) on the background of $N_\\textrm{c}$ color D2-branes (D3-branes). The Higgsing of the gauge group arises from the dissolution of some color branes inside the flavor branes. The dissolved color branes are represented by non-Abelian instantons whose backreaction is also included. The result is a cascading-like solution in which the effective number of color branes varies along the holographic direction. In the three-dimensional case the solution may include an arbitrary number of quasi-conformal (walking) regions.

  14. Branching process in a stochastic extremal model

    Science.gov (United States)

    Manna, S. S.

    2009-08-01

    We considered a stochastic version of the Bak-Sneppen model (SBSM) of ecological evolution where the number M of sites mutated in a mutation event is restricted to only two. Here the mutation zone consists of only one site and this site is randomly selected from the neighboring sites at every mutation event in an annealed fashion. The critical behavior of the SBSM is found to be the same as the BS model in dimensions d=1 and 2. However on the scale-free graphs the critical fitness value is nonzero even in the thermodynamic limit but the critical behavior is mean-field like. Finally ⟨M⟩ has been made even smaller than two by probabilistically updating the mutation zone, which also shows the original BS model behavior. We conjecture that a SBSM on any arbitrary graph with any small branching factor greater than unity will lead to a self-organized critical state.

  15. Blue Horizontal Branch Stars in M92

    CERN Document Server

    Cohen, J G

    1997-01-01

    We have analyzed high dispersion and high precision spectra of 5 blue horizontal branch stars in the globular cluster M92 to establish that the projected rotational velocity for these stars ranges from 15 to 40 \\kms. This is larger than that expected based on the rotation of their main sequence progenitors, the spin down of rotation with age, and the conservation of angular momentum. Possible explanations include a rapidly rotating stellar core. An abundance analysis of these spectra of these blue HB stars in M92 yields the same results as have been obtained from the giants in this cluster. There is a hint of a trend of higher abundance as the projected surface rotational velocity increases, which could be chance and requires confirmation.

  16. Simple statistical model for branched aggregates

    DEFF Research Database (Denmark)

    Lemarchand, Claire; Hansen, Jesper Schmidt

    2015-01-01

    We propose a statistical model that can reproduce the size distribution of any branched aggregate, including amylopectin, dendrimers, molecular clusters of monoalcohols, and asphaltene nanoaggregates. It is based on the conditional probability for one molecule to form a new bond with a molecule......, given that it already has bonds with others. The model is applied here to asphaltene nanoaggregates observed in molecular dynamics simulations of Cooee bitumen. The variation with temperature of the probabilities deduced from this model is discussed in terms of statistical mechanics arguments....... The relevance of the statistical model in the case of asphaltene nanoaggregates is checked by comparing the predicted value of the probability for one molecule to have exactly i bonds with the same probability directly measured in the molecular dynamics simulations. The agreement is satisfactory...

  17. Basic Sciences Branch annual report, FY 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1989, through September 30, 1990. Six technical sections of the report cover these main areas of NREL's in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Solid-State Spectroscopy. Each section of the report was written by the group leader principally in charge of the work. The task in each case was to explain the purpose and major accomplishments of the work in the context of the US Department of Energy's National Photovoltaic Research Program plans.

  18. Basic Sciences Branch annual report, FY 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-01

    This report summarizes the progress of the Basic Sciences Branch of the National Renewable Energy Laboratory (NREL) from October 1, 1989, through September 30, 1990. Six technical sections of the report cover these main areas of NREL`s in-house research: Semiconductor Crystal Growth, Amorphous Silicon Research, Polycrystalline Thin Films, III-V High-Efficiency Photovoltaic Cells, Solid-State Theory, and Solid-State Spectroscopy. Each section of the report was written by the group leader principally in charge of the work. The task in each case was to explain the purpose and major accomplishments of the work in the context of the US Department of Energy`s National Photovoltaic Research Program plans.

  19. Cold holographic matter in the Higgs branch

    Science.gov (United States)

    Itsios, Georgios; Jokela, Niko; Ramallo, Alfonso V.

    2015-07-01

    We study collective excitations of cold (2 + 1)-dimensional fundamental matter living on a defect of the four-dimensional N = 4 super Yang-Mills theory in the Higgs branch. This system is realized holographically as a D3-D5 brane intersection, in which the D5-brane is treated as a probe with a non-zero gauge flux across the internal part of its worldvolume. We study the holographic zero sound mode in the collisionless regime at low temperature and find a simple analytic result for its dispersion relation. We also find the diffusion constant of the system in the hydrodynamic regime at higher temperature. In both cases we study the dependence on the flux parameter which determines the amount of Higgs symmetry breaking. We also discuss the anyonization of this construction.

  20. Cold holographic matter in the Higgs branch

    CERN Document Server

    Itsios, Georgios; Ramallo, Alfonso V

    2015-01-01

    We study collective excitations of cold (2+1)-dimensional fundamental matter living on a defect of the four-dimensional N=4 super Yang-Mills theory in the Higgs branch. This system is realized holographically as a D3-D5 brane intersection, in which the D5-brane is treated as a probe with a non-zero gauge flux across the internal part of its worldvolume. We study the holographic zero sound mode in the collisionless regime at low temperature and find a simple analytic result for its dispersion relation. We also find the diffusion constant of the system in the hydrodynamic regime at higher temperature. In both cases we study the dependence on the flux parameter which determines the amount of Higgs symmetry breaking. We also discuss the anyonization of this construction.

  1. Cold holographic matter in the Higgs branch

    Directory of Open Access Journals (Sweden)

    Georgios Itsios

    2015-07-01

    Full Text Available We study collective excitations of cold (2+1-dimensional fundamental matter living on a defect of the four-dimensional N=4 super Yang–Mills theory in the Higgs branch. This system is realized holographically as a D3–D5 brane intersection, in which the D5-brane is treated as a probe with a non-zero gauge flux across the internal part of its worldvolume. We study the holographic zero sound mode in the collisionless regime at low temperature and find a simple analytic result for its dispersion relation. We also find the diffusion constant of the system in the hydrodynamic regime at higher temperature. In both cases we study the dependence on the flux parameter which determines the amount of Higgs symmetry breaking. We also discuss the anyonization of this construction.

  2. Planets around Extreme Horizontal Branch Stars

    CERN Document Server

    Bear, E

    2011-01-01

    We review three main results of our recent study: We show that a proper treatment of the tidal interaction prior to the onset of the common envelope (CE) leads to an enhance mass loss. This might increase the survivability of planets and brown dwarfs that enter a CE phase. From the distribution of planets around main sequence stars, we conclude that around many sdB/sdO stars more than one planet might be present. One of these might have a close orbit and the others at about orbital periods of years or more. We show that the intense ionizing flux of the extreme horizontal branch star might evaporate large quantities of a very close surviving substellar object. Balmer emission lines from the evaporated gas can be detected via their Doppler shifts.

  3. Planets around extreme horizontal branch stars

    CERN Document Server

    Bear, Ealeal

    2010-01-01

    We review three main results of our recent study: * We show that a proper treatment of the tidal interaction prior to the onset of the common envelope (CE) leads to an enhance mass loss. This might increase the survivability of planets and brown dwarfs that enter a CE phase. * From the distribution of planets around main sequence stars, we conclude that around many sdB/sdO stars more than one planet might be present. One of these might have a close orbit and the others at about orbital periods of years or more. * We show that the intense ionizing flux of the extreme horizontal branch star might evaporate large quantities of a very close surviving substellar object. Balmer emission lines from the evaporated gas can be detected via their Doppler shifts.

  4. Flight Dynamics Analysis Branch 2005 Technical Highlights

    Science.gov (United States)

    2005-01-01

    This report summarizes the major activities and accomplishments carried out by the Flight Dynamics Analysis Branch (FDAB), Code 595, in support of flight projects and technology development initiatives in Fiscal Year (FY) 2005. The report is intended to serve as a summary of the type of support carried out by the FDAB, as well as a concise reference of key accomplishments and mission experience derived from the various mission support roles. The primary focus of the FDAB is to provide expertise in the disciplines of flight dynamics including spacecraft navigation (autonomous and ground based); spacecraft trajectory design and maneuver planning; attitude analysis; attitude determination and sensor calibration; and attitude control subsystem (ACS) analysis and design. The FDAB currently provides support for missions and technology development projects involving NASA, other government agencies, academia, and private industry.

  5. Distinct structures of the α-fucose branches in fucosylated chondroitin sulfates do not affect their anticoagulant activity.

    Science.gov (United States)

    Santos, Gustavo R C; Glauser, Bianca F; Parreiras, Luane A; Vilanova, Eduardo; Mourão, Paulo A S

    2015-10-01

    Fucosylated chondroitin sulfate (FCS) is a glycosaminoglycan found in sea cucumbers. It has a backbone like that of mammalian chondroitin sulfate (4-β-d-GlcA-1→3-β-d-GalNAc-1)n but substituted at the 3rd position of the β-d-glururonic acid residues with α-fucose branches. The structure of these branches varies among FCSs extracted from different species of sea cucumbers, as revealed by solution NMR spectroscopy. Some species (Isostichopus badionotus and Patalus mollis) contain branches formed by single α-fucose residues but with variable sulfation patterns (2,4-, 3,4- and 4-sulfation). FCS from Ludwigothurea grisea is distinguished because it contains preponderant branches formed by disaccharide units containing non-sulfated and 3-sulfated α-fucose units at the reducing and non-reducing ends, respectively. Despite the structural variability on their α-fucose branches, these FCSs have similar anticoagulant action on assays using purified reagents. They have serpin-dependent and serpin-independent effects. Pharmacological assays using experimental animals showed that the three types of FCSs have similar antithrombotic effect and bleeding tendency. They also activate factor XII on the same range of concentration. Based on these observations, we proposed that only few sulfated α-fucose branches along the FCS chain are enough to assure the binding of this glycosaminoglycan to proteins of the coagulation system. Substitution with additional sulfated α-fucose does not increase further the activity. Overall, the use of FCSs with marked variability on their branches of α-fucose allowed us to establish correlations between structures vs biological effects of these glycosaminoglycans on a more refined basis. It opens new avenues for therapeutic intervention using FCSs.

  6. Branch xylem density variations across Amazonia

    Directory of Open Access Journals (Sweden)

    S. Patiño

    2008-05-01

    Full Text Available Measurements of branch xylem density, Dx, were made for 1466 trees representing 503 species, sampled from 80 sites across the Amazon basin. Measured values ranged from 240 kg m−3 for a Brosimum parinarioides from Tapajos in West Pará, Brazil to 1130 kg m−3 for an Aiouea sp. from Caxiuana, Central Pará, Brazil. Analysis of variance showed significant differences in average Dx across the sample plots as well as significant differences between families, genera and species. A partitioning of the total variance in the dataset showed that geographic location and plot accounted for 33% of the variation with species identity accounting for an additional 27%; the remaining "residual" 40% of the variance accounted for by tree to tree (within species variation. Variations in plot means, were, however, hardly accountable at all by differences in species composition. Rather, it would seem that variations of xylem density at plot level must be explained by the effects of soils and/or climate. This conclusion is supported by the observation that the xylem density of the more widely distributed species varied systematically from plot to plot. Thus, as well as having a genetic component branch xylem density is a plastic trait that, for any given species, varies according to where the tree is growing and in a predictable manner. Exceptions to this general rule may be some pioneers belonging to Pourouma and Miconia and some species within the genera Brosimum, Rinorea and Trichillia which seem to be more constrained in terms of this plasticity than most species sampled as part of this study.

  7. Development Value Chains meet Business Supply Chains : The concept of Global Value Chains unraveled

    NARCIS (Netherlands)

    S. Drost (Sarah); J.C.A.C. van Wijk (Jeroen); S. Vellema (Sietze)

    2011-01-01

    textabstractValue chain promotion is considered a key element of private sector development strategies and pro-poor growth. However, (value) chain concepts are rather complex and unclear. This paper unravels the concept of global value chains and studies the diversity of key value chain-related (sup

  8. Economy, market and chain

    NARCIS (Netherlands)

    Sukkel, W.; Hommes, M.

    2009-01-01

    In their pursuit of growth and professionalisation, the Dutch organic sector focuses primarily on market development. But how do you stimulate the market for organic foods? This is the subject of many research projects concerning market, consumer preferences and the supply chain. These projects focu

  9. Plastic value chains

    DEFF Research Database (Denmark)

    Baxter, John; Wahlstrom, Margareta; Zu Castell-Rüdenhausen, Malin;

    2014-01-01

    Optimizing plastic value chains is regarded as an important measure in order to increase recycling of plastics in an efficient way. This can also lead to improved awareness of the hazardous substances contained in plastic waste, and how to avoid that these substances are recycled. As an example...

  10. Innovation in Supply Chains

    DEFF Research Database (Denmark)

    Maier, Maximilian; Korbel, Jakob; Brem, Alexander

    2015-01-01

    . Moreover, along with the fourth industrial revolution – industry 4.0 – new technologies such as cyber physical systems are fast gaining popularity. Hence, based on the analysis of relevant literature, we further develop the supply chain committee model, developed by Kaluza et al. (2003) to demonstrate how...

  11. Shared Value Chain Design

    DEFF Research Database (Denmark)

    Bals, Lydia; Tate, Wendy L.

    In Sustainable Supply Chain Management (SSCM) research still the classic economic perspective is the dominating perspective, although the triple bottom line (including economic, social and ecological) is well accepted. The theoretical foundation for the paper is Stakeholder Theory. Case studies o...

  12. Sustainable Supply Chain Design

    DEFF Research Database (Denmark)

    Bals, Lydia; Tate, Wendy

    A significant conceptual and practical challenge is how to integrate triple bottom line (TBL; including economic, social and environmental) sustainability into global supply chains. Although this integration is necessary to slow down global resource depletion, understanding is limited of how to i...

  13. CHAINE DES ROTISSEUR @ HILTON

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The annual gala dinner of Chaine des Rotisseurs was hosted by Hilton Beijing. The “Ballet Dinner” - a great creation for both art and fine dining lovers was taken place in varies places within the hotel, including hotel lobby, 3rd floor and lobby lounge.

  14. Exploration Supply Chain Simulation

    Science.gov (United States)

    2008-01-01

    The Exploration Supply Chain Simulation project was chartered by the NASA Exploration Systems Mission Directorate to develop a software tool, with proper data, to quantitatively analyze supply chains for future program planning. This tool is a discrete-event simulation that uses the basic supply chain concepts of planning, sourcing, making, delivering, and returning. This supply chain perspective is combined with other discrete or continuous simulation factors. Discrete resource events (such as launch or delivery reviews) are represented as organizational functional units. Continuous resources (such as civil service or contractor program functions) are defined as enabling functional units. Concepts of fixed and variable costs are included in the model to allow the discrete events to interact with cost calculations. The definition file is intrinsic to the model, but a blank start can be initiated at any time. The current definition file is an Orion Ares I crew launch vehicle. Parameters stretch from Kennedy Space Center across and into other program entities (Michaud Assembly Facility, Aliant Techsystems, Stennis Space Center, Johnson Space Center, etc.) though these will only gain detail as the file continues to evolve. The Orion Ares I file definition in the tool continues to evolve, and analysis from this tool is expected in 2008. This is the first application of such business-driven modeling to a NASA/government-- aerospace contractor endeavor.

  15. Supply chain reliability modelling

    Directory of Open Access Journals (Sweden)

    Eugen Zaitsev

    2012-03-01

    Full Text Available Background: Today it is virtually impossible to operate alone on the international level in the logistics business. This promotes the establishment and development of new integrated business entities - logistic operators. However, such cooperation within a supply chain creates also many problems related to the supply chain reliability as well as the optimization of the supplies planning. The aim of this paper was to develop and formulate the mathematical model and algorithms to find the optimum plan of supplies by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Methods: The mathematical model and algorithms to find the optimum plan of supplies were developed and formulated by using economic criterion and the model for the probability evaluating of non-failure operation of supply chain. Results and conclusions: The problem of ensuring failure-free performance of goods supply channel analyzed in the paper is characteristic of distributed network systems that make active use of business process outsourcing technologies. The complex planning problem occurring in such systems that requires taking into account the consumer's requirements for failure-free performance in terms of supply volumes and correctness can be reduced to a relatively simple linear programming problem through logical analysis of the structures. The sequence of the operations, which should be taken into account during the process of the supply planning with the supplier's functional reliability, was presented.

  16. Standard handbook of chains chains for power transmission and material handling

    CERN Document Server

    Chain Association, American

    2005-01-01

    A BRIEF HISTORY OF THE DEVELOPMENT OF CHAINEarly DevelopmentsCog ChainCast Detachable ChainCast Pintle ChainPrecision Roller ChainEngineering Steel ChainSilent ChainFlat-Top ChainTerminologyA CHAIN OVERVIEW: USES AND ADVANTAGESGeneralTypes of ChainScope of Chains CoveredStyles and Forms of ChainsStraight and Offset Link ChainsChains With and Without RollersUses of ChainStandard Chains and Their UsesThe Advantages of Chains in ApplicationsAdvantages of Roller Chains in DrivesAdvantages of Silent Chain Drives

  17. Command and Data Handling Branch Internship

    Science.gov (United States)

    Billings, Rachel Mae

    2016-01-01

    Modular Integrated Stackable Layers (MISL) is a computer system designed for simple, fast, and cost effective flexible reconfiguration in space environments such as the ISS and Orion projects for various uses. Existing applications include wireless and wired communications, data acquisition and instrumentation, and camera systems, and potential applications include bus protocol converters and subsystem control. MISL is based on Texas Instruments (TI)' MSP430 16-bit ultra-low-power microcontroller device. The purpose of my project was to integrate the MISL system with a liquid crystal display (LCD) touchscreen. The LCD, manufactured by Crystalfontz and part number CFAF320240F-035T-TS, is a 320 by 240 RGB resistive color screen including an optional carrier board. The vast majority of the project was done with Altium Designer, a tool for printed circuit board (PCB) schematic capture, 3D design, and FPGA (Field Programmable Gate Array) development. The new PCB was to allow the LCD to directly stack to the rest of MISL. Research was done with datasheets for the TI microcontroller and touchscreen display in order to meet desired hardware specifications. Documentation on prior MISL projects was also utilized. The initial step was to create a schematic for the LCD, power bus, and data bus connections between components. A layout was then designed with the required physical dimensions, routed traces and vias, power and ground planes, layer stacks, and other specified design rules such as plane clearance and hole size. Multiple consultation sessions were held with Hester Yim, the technical discipline lead for the Command and Data Handling Branch, and Christy Herring, the lead PCB layout designer in the Electronic Design and Manufacturing Branch in order to ensure proper configuration. At the moment, the PCB is awaiting revision by the latter-mentioned branch. Afterwards, the board will begin to undergo the manufacturing and testing process. Throughout the internship at

  18. Branched projective structures with quasi-Fuchsian holonomy

    CERN Document Server

    Calsamiglia, Gabriel; Francaviglia, Stefano

    2012-01-01

    We prove that if S is a closed compact surface of negative Euler characteristic, and if R is a quasi-Fuchsian representation in PSL(2,C), then the deformation space M(k,R) of branched projective structures on S with total branching order k and holonomy R is connected, as soon as k>0. Equivalently, two branched projective structures with the same quasi-Fuchsian holonomy and the same number of branch points are related by a movement of branch points. In particular grafting annuli are obtained by moving branch points. In the appendix we give an explicit atlas for the space M(k,R). It is shown to be a smooth complex manifold modeled on Hurwitz spaces.

  19. The Horizontal Branch of the Sculptor Dwarf galaxy

    CERN Document Server

    Salaris, Maurizio; Tolstoy, Eline; Fiorentino, Giuliana; Cassisi, Santi

    2013-01-01

    We have performed the first detailed simulation of the horizontal branch of the Sculptor dwarf spheroidal galaxy by means of synthetic modelling techniques,taking consistently into account the star formation history and metallicity evolution as determined from the main sequence and red giant branch spectroscopic observations. The only free parameter in the whole analysis is the integrated mass loss of red giant branch stars. This is the first time that synthetic horizontal branch models, consistent with the complex star formation history of a galaxy, are calculated and matched to the observations. We find that the metallicity range covered by the star formation history, as constrained by observations, plus a simple mass loss law, enable us to cover both the full magnitude and colour range of HB stars. In addition the number count distribution along the observed horizontal branch, can be also reproduced, provided that the red giant branch mass loss is mildly metallicity dependent, with a very small dispersion ...

  20. Deregulation of Bank Entry and Branching: Impact on Competition

    OpenAIRE

    Milo, Melanie S.

    2001-01-01

    This paper looks at public policy towards bank entry and branching in the Philippines and its impact on the sector’s structure, conduct and performance. In particular, it argues that regulatory restrictions on bank entry and branching have had adverse effects on competition, while the liberalization of these restrictions have led to a more competitive banking sector. The paper has two main sections. Section II presents the history of regulation of bank entry and branching in the Philippines. ...

  1. Persistence-Based Branch Misprediction Bounds for WCET Analysis

    DEFF Research Database (Denmark)

    Puffitsch, Wolfgang

    2015-01-01

    Branch prediction is an important feature of pipelined processors to achieve high performance. However, it can lead to overly pessimistic worst-case execution time (WCET) bounds when being modeled too conservatively. This paper presents bounds on the number of branch mispredictions for local dyna...... linear programming formulations of the WCET problem. An evaluation on a number of benchmarks shows that with these bounds, dynamic branch prediction does not necessarily lead to higher WCET bounds than static prediction schemes....

  2. Branch structure of corona discharge: experimental simulation and chemical properties

    International Nuclear Information System (INIS)

    The branch structure of corona discharge has been investigated via C2H2 corona discharge. Carbon filament with excellent branch structure is formed in the discharge. This carbon filament offers a direct mimic of the branch structure of corona discharge. It provides a very useful way to study on the average energy, physical and chemical characteristics of corona discharge. On this basis, the chemical property of corona discharge for methane conversion is discussed. (authors)

  3. Activities of the Development Branch. 1978-1981

    International Nuclear Information System (INIS)

    The activities carried out by the Development Branch from 1978 through 1981 are summarized. Subjects covered include: Metallurgy, Nuclear Fuels, Instrumentation and Control, Nuclear Reactors, as well as the various projects developed during this period and the administrative and technical activities of various groups belonging to this Branch. A list of publications by personnel of this Branch during the same period is also included. (C.A.K.)

  4. The Branching of Graphs in 2-d Quantum Gravity

    OpenAIRE

    Harris, M. G.

    1996-01-01

    The branching ratio is calculated for three different models of 2d gravity, using dynamical planar phi-cubed graphs. These models are pure gravity, the D=-2 Gaussian model coupled to gravity and the single spin Ising model coupled to gravity. The ratio gives a measure of how branched the graphs dominating the partition function are. Hence it can be used to estimate the location of the branched polymer phase for the multiple Ising model coupled to 2d gravity.

  5. Human vagus nerve branching in the cervical region.

    Directory of Open Access Journals (Sweden)

    Niels Hammer

    Full Text Available Vagus nerve stimulation is increasingly applied to treat epilepsy, psychiatric conditions and potentially chronic heart failure. After implanting vagus nerve electrodes to the cervical vagus nerve, side effects such as voice alterations and dyspnea or missing therapeutic effects are observed at different frequencies. Cervical vagus nerve branching might partly be responsible for these effects. However, vagus nerve branching has not yet been described in the context of vagus nerve stimulation.Branching of the cervical vagus nerve was investigated macroscopically in 35 body donors (66 cervical sides in the carotid sheath. After X-ray imaging for determining the vertebral levels of cervical vagus nerve branching, samples were removed to confirm histologically the nerve and to calculate cervical vagus nerve diameters and cross-sections.Cervical vagus nerve branching was observed in 29% of all cases (26% unilaterally, 3% bilaterally and proven histologically in all cases. Right-sided branching (22% was more common than left-sided branching (12% and occurred on the level of the fourth and fifth vertebra on the left and on the level of the second to fifth vertebra on the right side. Vagus nerves without branching were significantly larger than vagus nerves with branches, concerning their diameters (4.79 mm vs. 3.78 mm and cross-sections (7.24 mm2 vs. 5.28 mm2.Cervical vagus nerve branching is considerably more frequent than described previously. The side-dependent differences of vagus nerve branching may be linked to the asymmetric effects of the vagus nerve. Cervical vagus nerve branching should be taken into account when identifying main trunk of the vagus nerve for implanting electrodes to minimize potential side effects or lacking therapeutic benefits of vagus nerve stimulation.

  6. Pressure Change in Tee Branch Pipe in Oscillatory Flow

    OpenAIRE

    Daisuke Sakamoto; Chongho Youn; Toshiharu Kagawa

    2013-01-01

    The purpose of this paper is to contribute to the understanding of unsteady flow of branch pipes in pneumatic systems. Branch pipes are used in pneumatic pipe systems in various industrial fields. To predict the unsteady pressure changes in the pneumatic piping systems, it is necessary that the dynamic characteristics of branch pipes are at hand, in addition to the dynamic characteristic of single pipe. However, while so many studies are accumulated for a single pipe dynamics, few studies hav...

  7. Interaction forces between surfaces coated with highly branched polyelectrolytes

    OpenAIRE

    Pericet-Cámara, Ramón; Borkovec, Michal

    2007-01-01

    In this thesis, interactions between surfaces with adsorbed highly branched polyelectrolytes were studied with the colloidal probe technique. By studying the adsorption behavior of highly branched polyelectrolytes, the lateral distribution of the surface charge could be tuned by the appropriate adsorption conditions. By choosing different polyelecrtrolytes, namely highly branched poly(ethylenimine) (PEI) and poly(amido amine) (PAMAM) dendrimers, it was possible to investigate the forces betwe...

  8. Interaction forces between surfaces coated with highly branched polyelectrolytes

    OpenAIRE

    Pericet-Cámara, Ramón

    2006-01-01

    In this thesis, interactions between surfaces with adsorbed highly branched polyelectrolytes were studied with the colloidal probe technique. By studying the adsorption behavior of highly branched polyelectrolytes, the lateral distribution of the surface charge could be tuned by the appropriate adsorption conditions. By choosing different polyelecrtrolytes, namely highly branched poly(ethylenimine) (PEI) and poly(amido amine) (PAMAM) dendrimers, it was possible to investigate the forces betwe...

  9. The normal distribution of thoracoabdominal aorta small branch artery ostia

    International Nuclear Information System (INIS)

    The purpose of this study was to determine the normal distribution of aortic branch artery ostia. CT scans of 100 subjects were retrospectively reviewed. The angular distributions of the aorta with respect to the center of the T3 to L4 vertebral bodies, and of branch artery origins with respect to the center of the aorta were measured. At each vertebral body level the distribution of intercostal/lumbar arteries and other branch arteries were calculated. The proximal descending aorta is posteriorly placed becoming a midline structure, at the thoracolumbar junction, and remains anterior to the vertebral bodies within the abdomen. The intercostal and lumbar artery ostia have a distinct distribution. At each vertebral level from T3 caudally, one intercostal artery originates from the posterior wall of the aorta throughout the thoracic aorta, while the other intercostal artery originates from the medial wall of the descending thoracic aorta high in the chest, posteromedially from the mid-thoracic aorta, and from the posterior wall of the aorta low in the chest. Mediastinal branches of the thoracic aorta originate from the medial and anterior wall. Lumbar branches originate only from the posterior wall of the abdominal aorta. Aortic branch artery origins arise with a bimodal distribution and have a characteristic location. Mediastinal branches of the thoracic aorta originate from the medial and anterior wall. Knowing the location of aortic branch artery ostia may help distinguish branch artery pseudoaneurysms from penetrating ulcers.

  10. [Variability of the celiac artery and its branches in sheep].

    Science.gov (United States)

    Karmona, Kh; Kovachev, G

    1985-01-01

    Contrast matter was used with a total of 363 sheep fetuses, newborn lambs, and adult sheep to study the variability of the coeliac artery and its branches. It was found that the artery and some of its branches, such as arteria ruminalis sinistra, arteria reticularis, and arteria lienalis often showed variations, resp., deviations in their branching and distribution. Others, such as arteria ruminalis dextra and arteria hepatica showed no variations whatever. Both the coeliac artery and the anterior intestinal artery in the sheep were most often shown to branch from the aorta alone (in 71.07 per cent of the cases) as against the rarely observed common truncus coeliacomesentericus (in 28.93 per cent of the cases). The most commonly observed form of branching of arteria coeliaca seemed to be tripus coeliacus, while the branching with the formation of a short truncus hepatogastricus was comparatively a rare phenomenon. It was also established that the left ruminal artery was much more frequently the branch of truncus lienoruminalis than the branch of arteria gastrica sinistra. So far as the place in which arteria reticularis arose three variants were observed. Most frequently this artery was shown to be the branch of arteria gastrica sinistra. PMID:4013078

  11. Branched RNA: A New Architecture for RNA Interference

    Directory of Open Access Journals (Sweden)

    Anna Aviñó

    2011-01-01

    Full Text Available Branched RNAs with two and four strands were synthesized. These structures were used to obtain branched siRNA. The branched siRNA duplexes had similar inhibitory capacity as those of unmodified siRNA duplexes, as deduced from gene silencing experiments of the TNF-α protein. Branched RNAs are considered novel structures for siRNA technology, and they provide an innovative tool for specific gene inhibition. As the method described here is compatible with most RNA modifications described to date, these compounds may be further functionalized to obtain more potent siRNA derivatives and can be attached to suitable delivery systems.

  12. China Strengthens Macro-management in Petrochemical Branches

    Institute of Scientific and Technical Information of China (English)

    Xu Hui

    1997-01-01

    @@ China will strengthen macro-management in petrochemical branches in order to reasonably utilize the national petroleum resources and improve its competitive capacity in international refinery industrial market.

  13. The design of supply chains

    DEFF Research Database (Denmark)

    Bøge Sørensen, Lars

    2004-01-01

    Keywords Supply Chain Management, Supply Chain Design, Literature studyAbstract Argues stability is a design objective for supply chain design alongside cost, leadtime and responsiveness. Performs an extensive literature study on supply chain design,identifies methods, theories and objectives...... in the existing literature. Describes the conceptexternal specificity and how it's used to design supply chains. Using the concept upstream,archetypes of risk minimal and maximal design are identified. Downstream the conceptdescribes two viable scenarios, one minimizing the impact, the other minimizing...... theprobability of (intended) departure of a supply chain partner. Finally, principles for supplychain design are described and managerial outlined....

  14. CYANOGEN IN NGC 1851 RED GIANT BRANCH AND ASYMPTOTIC GIANT BRANCH STARS: QUADRIMODAL DISTRIBUTIONS

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, S. W.; Stancliffe, R. J.; Lattanzio, J. C.; Angelou, G. C.; D' Orazi, V. [Monash Centre for Astrophysics, P.O. Box 28M, Victoria 3800 (Australia); Yong, D.; Wylie-de Boer, E. C. [Research School of Astronomy and Astrophysics, Australian National University, Weston, ACT 2611 (Australia); Martell, S. L. [Australian Astronomical Observatory, North Ryde, NSW 2113 (Australia); Grundahl, F. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade, DK-8000 Aarhus C (Denmark); Sneden, C., E-mail: simon.campbell@monash.edu, E-mail: david.yong@anu.edu.au [Department of Astronomy and McDonald Observatory, University of Texas, Austin, TX 78712 (United States)

    2012-12-10

    The Galactic globular cluster NGC 1851 has raised much interest since Hubble Space Telescope photometry revealed that it hosts a double subgiant branch. Here we report on our homogeneous study into the cyanogen (CN) band strengths in the red giant branch (RGB) population (17 stars) and asymptotic giant branch (AGB) population (21 stars) using AAOmega/2dF spectra with R {approx} 3000. We discover that NGC 1851 hosts a quadrimodal distribution of CN band strengths in its RGB and AGB populations. This result supports the merger formation scenario proposed for this cluster, such that the CN quadrimodality could be explained by the superposition of two 'normal' bimodal populations. A small sample overlap with an abundance catalog allowed us to tentatively explore the relationship between our CN populations and a range of elemental abundances. We found a striking correlation between CN and [O/Na]. We also found that the four CN peaks may be paired-the two CN-weaker populations being associated with low Ba and the two CN-stronger populations with high Ba. If true, then s-process abundances would be a good diagnostic for disentangling the two original clusters in the merger scenario. More observations are needed to confirm the quadrimodality and also the relationship between the subpopulations. We also report CN results for NGC 288 as a comparison. Our relatively large samples of AGB stars show that both clusters have a bias toward CN-weak AGB populations.

  15. Decision-Making for Supply Chain Integration Supply Chain Integration

    CERN Document Server

    Lettice, Fiona; Durowoju, Olatunde

    2012-01-01

    Effective supply chain integration, and the tight co-ordination it creates, is an essential pre-requisite for successful supply chain management.  Decision-Making for Supply Chain Integration is a practical reference on recent research in the area of supply chain integration focusing on distributed decision-making problems. Recent applications of various decision-making tools for integrating supply chains are covered including chapters focusing on: •Supplier selection, pricing strategy and inventory decisions in multi-level supply chains, •RFID-enabled distributed decision-making, •Operational risk issues and time-critical decision-making for sensitive logistics nodes, Modelling end to end processes to improve supply chain integration, and •Integrated systems to improve service delivery and optimize resource use. Decision-Making for Supply Chain Integration provides an insight into the tools and methodologies of this field with support from real-life case studies demonstrating successful application ...

  16. Extended linear chain compounds

    CERN Document Server

    Linear chain substances span a large cross section of contemporary chemistry ranging from covalent polymers, to organic charge transfer com­ plexes to nonstoichiometric transition metal coordination complexes. Their commonality, which coalesced intense interest in the theoretical and exper­ imental solid state physics/chemistry communities, was based on the obser­ vation that these inorganic and organic polymeric substrates exhibit striking metal-like electrical and optical properties. Exploitation and extension of these systems has led to the systematic study of both the chemistry and physics of highly and poorly conducting linear chain substances. To gain a salient understanding of these complex materials rich in anomalous aniso­ tropic electrical, optical, magnetic, and mechanical properties, the conver­ gence of diverse skills and talents was required. The constructive blending of traditionally segregated disciplines such as synthetic and physical organic, inorganic, and polymer chemistry, crystallog...

  17. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud;

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen-...... for combating HER2+ breast cancer. © 2013 by Tabriz University of Medical Sciences.......Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen......-binding fragments in cancer targeting and therapy. VHHs express low immunogenicity, are highly robust and easy to manufacture and have the ability to recognize hidden or uncommon epitopes. We highlight the utility of VHH in design of new molecular, multifunctional particulate and immune cell-based systems...

  18. Perioperative supply chain management.

    Science.gov (United States)

    Feistritzer, N R; Keck, B R

    2000-09-01

    Faced with declining revenues and increasing operating expenses, hospitals are evaluating numerous mechanisms designed to reduce costs while simultaneously maintaining quality care. Many facilities have targeted initial cost reduction efforts in the reduction of labor expenses. Once labor expenses have been "right sized," facilities have continued to focus on service delivery improvements by the optimization of the "supply chain" process. This report presents a case study of the efforts of Vanderbilt University Medical Center in the redesign of its supply chain management process in the department of Perioperative Services. Utilizing a multidisciplinary project management structure, 3 work teams were established to complete the redesign process. To date, the project has reduced costs by $2.3 million and enhanced quality patient care by enhancing the delivery of appropriate clinical supplies during the perioperative experience.

  19. Volumes of chain links

    CERN Document Server

    Kaiser, James; Rollins, Clint

    2011-01-01

    Agol has conjectured that minimally twisted n-chain links are the smallest volume hyperbolic manifolds with n cusps, for n at most 10. In his thesis, Venzke mentions that these cannot be smallest volume for n at least 11, but does not provide a proof. In this paper, we give a proof of Venzke's statement. The proof for n at least 60 is completely rigorous. The proof for n between 11 and 59 uses a computer calculation, and can be made rigorous for manifolds of small enough complexity, using methods of Moser and Milley. Finally, we prove that the n-chain link with 2m or 2m+1 half-twists cannot be the minimal volume hyperbolic manifold with n cusps, provided n is at least 60 or |m| is at least 8, and we give computational data indicating this remains true for smaller n and |m|.

  20. Towards Intelligent Supply Chains

    DEFF Research Database (Denmark)

    Siurdyban, Artur; Møller, Charles

    2012-01-01

    of deploying inapt operations leading to deterioration of profits. To address this problem, we propose a unified business process design framework based on the paradigm of intelligence. Intelligence allows humans and human-designed systems cope with environmental volatility, and we argue that its principles...... applied to the context of organizational processes can increase the success rate of business operations. The framework is created using a set of theoretical based constructs grounded in a discussion across several streams of research including psychology, pedagogy, artificial intelligence, learning......, business process management and supply chain management. It outlines a number of system tasks combined in four integrated management perspectives: build, execute, grow and innovate, put forward as business process design propositions for Intelligent Supply Chains....