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Sample records for control product stereochemistry

  1. CO2 copolymers from epoxides: catalyst activity, product selectivity, and stereochemistry control.

    Science.gov (United States)

    Lu, Xiao-Bing; Ren, Wei-Min; Wu, Guang-Peng

    2012-10-16

    The use of carbon dioxide as a carbon source for the synthesis of organic chemicals can contribute to a more sustainable chemical industry. Because CO(2) is such a thermodynamically stable molecule, few effective catalysts are available to facilitate this transformation. Currently, the major industrial processes that convert CO(2) into viable products generate urea and hydroxybenzoic acid. One of the most promising new technologies for the use of this abundant, inexpensive, and nontoxic renewable resource is the alternating copolymerization of CO(2) and epoxides to provide biodegradable polycarbonates, which are highly valuable polymeric materials. Because this process often generates byproducts, such as polyether or ether linkages randomly dispersed within the polycarbonate chains and/or the more thermodynamically stable cyclic carbonates, the choice of catalyst is critical for selectively obtaining the expected product. In this Account, we outline our efforts to develop highly active Co(III)-based catalysts for the selective production of polycarbonates from the alternating copolymerization of CO(2) with epoxides. Binary systems consisting of simple (salen)Co(III)X and a nucleophilic cocatalyst exhibited high activity under mild conditions even at 0.1 MPa CO(2) pressure and afforded copolymers with >99% carbonate linkages and a high regiochemical control (∼95% head-to-tail content). Discrete, one-component (salen)Co(III)X complexes bearing an appended quaternary ammonium salt or sterically hindered Lewis base showed excellent activity in the selectively alternating copolymerization of CO(2) with both aliphatic epoxides and cyclohexene oxide at high temperatures with low catalyst loading and/or low pressures of CO(2). Binary or one-component catalysts based on unsymmetric multichiral Co(III) complexes facilitated the efficient enantioselective copolymerization of CO(2) with epoxides, providing aliphatic polycarbonates with >99% head-to-tail content. These

  2. Bacterial Sugar 3,4-Ketoisomerases: Structural Insight into Product Stereochemistry.

    Science.gov (United States)

    Thoden, James B; Vinogradov, Evgeny; Gilbert, Michel; Salinger, Ari J; Holden, Hazel M

    2015-07-28

    3-Acetamido-3,6-dideoxy-d-galactose (Fuc3NAc) and 3-acetamido-3,6-dideoxy-d-glucose (Qui3NAc) are unusual sugars found on the lipopolysaccharides of Gram-negative bacteria and on the S-layers of Gram-positive bacteria. The 3,4-ketoisomerases, referred to as FdtA and QdtA, catalyze the third steps in the respective biosynthetic pathways for these sugars. Whereas both enzymes utilize the same substrate, the stereochemistries of their products are different. Specifically, the hydroxyl groups at the hexose C-4' positions assume the "galactose" and "glucose" configurations in the FdtA and QdtA products, respectively. In 2007 we reported the structure of the apoform of FdtA from Aneurinibacillus thermoaerophilus, which was followed in 2014 by the X-ray analysis of QdtA from Thermoanaerobacterium thermosaccharolyticum as a binary complex. Both of these enzymes belong to the cupin superfamily. Here we report a combined structural and enzymological study to explore the manner in which these enzymes control the stereochemistry of their products. Various site-directed mutant proteins of each enzyme were constructed, and their dTDP-sugar products were analyzed by NMR spectroscopy. In addition, the kinetic parameters for these protein variants were measured, and the structure of one, namely, the QdtA Y17R/R97H double mutant form, was determined to 2.3-Å resolution. Finally, in an attempt to obtain a model of FdtA with a bound dTDP-linked sugar, the 3,4-ketoisomerase domain of a bifunctional enzyme from Shewanella denitrificans was cloned, purified, and crystallized in the presence of a dTDP-linked sugar analogue. Taken together, the results from this investigation demonstrate that it is possible to convert a "galacto" enzyme into a "gluco" enzyme and vice versa.

  3. Mathematical stereochemistry

    CERN Document Server

    Fujita, Shinsaku

    2015-01-01

    Chirality and stereogenicity are closely related concepts and their differentiation and description is still a challenge in chemoinformatics. A new stereoisogram approach, developed by the author, is introduced in this book, providing a theoretical framework for mathematical aspects of modern stereochemistry. The discussion covers point-groups and permutation symmetry and exemplifies the concepts using organic molecules and inorganic complexes.

  4. Practical Stereochemistry.

    Science.gov (United States)

    Kellogg, Richard M

    2017-03-01

    The relationship between fundamental and applied is often uneasy, particularly in modern political climates. A familiar political view, aimed negatively at the scientific community, is that the former is a waste of money whereas the latter gives value for investment. The answer that fundamental is required as the basis for practical suffers from the fact that the timelines between fundamental and practical are often long and the routes contorted and unexpected. This has been my experience. In this Account, examples are given from the research in which I have been involved wherein quite fundamental considerations have led to various applications. The longer the time, the clearer and broader the relationship. Fundamental can and does lead to application. They need and depend on each other. I have seen this both from the side of academia and from small companies. In the course of the past 40 plus years, I have been involved in various aspects of stereochemistry and, in particular, chirality. It has been rewarding to see that several of the developments, most originally grounded in fundamental research considerations, have been used in the chemical community and given new dimensions and often practical applications by others. In this Account, a path-not planned deliberately by me-from orbital symmetry and Woodward-Hoffmann rules through crown ethers to conformational analysis to diastereomeric resolutions to deracemizations powered by Ostwald ripening and the Gibbs-Thomson effect to nucleation to helicenes is described. In order of discussion, the orbital symmetry aspects have via an unusual and unpredicted path has resulted in, among other things, a synthesis of hindered alkenes useful for the production of molecular motors. The crown ether aspects led to discovery of the utility of cesium salts particularly for racemization sensitive nucleophilic substitutions. Work on diastereomeric resolutions has concentrated on the mechanistic as well as practical

  5. A new enzyme involved in the control of the stereochemistry in the decalin formation during equisetin biosynthesis.

    Science.gov (United States)

    Kato, Naoki; Nogawa, Toshihiko; Hirota, Hiroshi; Jang, Jae-Hyuk; Takahashi, Shunji; Ahn, Jong Seog; Osada, Hiroyuki

    2015-05-01

    Tetramic acid containing a decalin ring such as equisetin and phomasetin is one of the characteristic scaffolds found in fungal bioactive secondary metabolites. Polyketide (PKS)-nonribosomal peptide synthetase (NRPS) hybrid enzyme is responsible for the synthesis of the polyketide scaffold conjugated with an amino acid. PKS-NRPS hybrid complex programs to create structural diversity in the polyketide backbone have begun to be investigated, yet mechanism of control of the stereochemistry in a decalin formation via a Diels-Alder cycloaddition remains uncertain. Here, we demonstrate that fsa2, which showed no homology to genes encoding proteins of known function, in the fsa cluster responsible for equisetin and fusarisetin A biosynthesis in Fusarium sp. FN080326, is involved in the control of stereochemistry in decalin formation via a Diels-Alder reaction in the equisetin biosynthetic pathway.

  6. Stereochemistry Control in Direct 1α-Hydroxylation of 5,6-trans-Vitamin D3 by Solid Support

    Institute of Scientific and Technical Information of China (English)

    Yong Bin HAN; Jin Ping CHEN; Bai Ning LIU; Guo Qiang YANG; Yi LI

    2006-01-01

    A solid-phase synthesis of 1α-hydroxylation of 5,6-trans-vitamin D3 8 is described.The solid phase resin acts as a special protecting group, which gives a higher stereoselectivity in oxidation step than classical protecting groups. The stereochemistry control is favored by using high crosslinkage polymer support in a poor solvent. This work may be of benefit to the synthesis of vitamin D system.

  7. Controlling the stereochemistry and regularity of butanethiol self-assembled monolayers on Au(111)

    DEFF Research Database (Denmark)

    Yan, Jiawei; Ouyang, Runhai; Jensen, Palle Skovhus;

    2014-01-01

    The rich stereochemistry of the self-assembled monolayers (SAMs) of four butanethiols on Au(111) is described, the SAMs containing up to 12 individual C, S, or Au chiral centers per surface unit cell. This is facilitated by synthesis of enantiomerically pure 2-butanethiol (the smallest unsubstitu...

  8. Synthesis and Structural Properties of Aza[n]helicene Platinum Complexes: Control of Cis and Trans Stereochemistry.

    Science.gov (United States)

    Mendola, Daniele; Saleh, Nidal; Hellou, Nora; Vanthuyne, Nicolas; Roussel, Christian; Toupet, Loïc; Castiglione, Franca; Melone, Federica; Caronna, Tullio; Fontana, Francesca; Martí-Rujas, Javier; Parisini, Emilio; Malpezzi, Luciana; Mele, Andrea; Crassous, Jeanne

    2016-03-07

    The synthesis and structural characterization of azahelicene platinum complexes obtained from cis-PtCl2(NCEt)(PPh3) and from ligands that differ in terms of both the position of the nitrogen atom and the number of fused rings are reported. These square-planar complexes of the general formula PtCl2(nHm)(PPh3) (n = 4, 5; m = 5, 6) display mainly a cis configuration. However, by X-ray crystallographic analysis, we show that for both PtCl2(4H6)(PPh3) and PtCl2(5H6)(PPh3) there is chirality control of the cis/trans stereochemistry. Indeed, starting from a racemic mixture of aza[6]helicene, platinum complexes with a cis configuration are invariably obtained, and the more thermodynamically stable trans isomers are formed when using enantiopure ligands. We further corroborated these results by NMR analysis in solution.

  9. Design of highly active binary catalyst systems for CO2/epoxide copolymerization: polymer selectivity, enantioselectivity, and stereochemistry control.

    Science.gov (United States)

    Lu, Xiao-Bing; Shi, Lei; Wang, Yi-Ming; Zhang, Rong; Zhang, Ying-Ju; Peng, Xiao-Jun; Zhang, Zhi-Chao; Li, Bo

    2006-02-01

    Asymmetric, regio- and stereoselective alternating copolymerization of CO(2) and racemic aliphatic epoxides proceeds effectively under mild temperature and pressure by using a binary catalyst system of a chiral tetradentate Schiff base cobalt complex [SalenCo(III)X] as the electrophile in conjunction with an ionic organic ammonium salt or a sterically hindered strong organic base as the nucleophile. The substituent groups on the aromatic rings, chiral diamine backbone, and axial X group of the electrophile, as well as the nucleophilicity, leaving ability, and coordination ability of the nucleophile, all significantly affect the catalyst activity, polymer selectivity, enantioselectivity, and stereochemistry. A bulky chiral cyclohexenediimine backbone complex [SalcyCo(III)X] with an axial X group of poor leaving ability as the electrophile, combined with a bulky nuclephile with poor leaving ability and low coordination ability, is an ideal binary catalyst system for the copolymerization of CO(2) and a racemic aliphatic epoxide to selectively produce polycarbonates with relatively high enantioselectivity, >95% head-to-tail connectivity, and >99% carbonate linkages. A fast copolymerization of CO(2) and epoxides was observed when the concentration of the electrophile or/and the nucleophile was increased, and the number of polycarbonate chains was proportional to the concentration of the nucleophile. Electrospray ionization mass spectrometry, in combination with a kinetic study, showed that the copolymerization involved the coordination activation of the monomer by the electrophile and polymer chain growth predominately occurring in the nucleophile. Both the enantiomorphic site effect resulting from the chiral electrophile and the polymer chain end effect mainly from the bulky nucleophile cooperatively control the stereochemistry of the CO(2)/epoxide copolymerization.

  10. Controlling the stereochemistry and regularity of butanethiol self-assembled monolayers on au(111).

    Science.gov (United States)

    Yan, Jiawei; Ouyang, Runhai; Jensen, Palle S; Ascic, Erhad; Tanner, David; Mao, Bingwei; Zhang, Jingdong; Tang, Chunguang; Hush, Noel S; Ulstrup, Jens; Reimers, Jeffrey R

    2014-12-10

    The rich stereochemistry of the self-assembled monolayers (SAMs) of four butanethiols on Au(111) is described, the SAMs containing up to 12 individual C, S, or Au chiral centers per surface unit cell. This is facilitated by synthesis of enantiomerically pure 2-butanethiol (the smallest unsubstituted chiral alkanethiol), followed by in situ scanning tunneling microscopy (STM) imaging combined with density functional theory molecular dynamics STM image simulations. Even though butanethiol SAMs manifest strong headgroup interactions, steric interactions are shown to dominate SAM structure and chirality. Indeed, steric interactions are shown to dictate the nature of the headgroup itself, whether it takes on the adatom-bound motif RS(•)Au(0)S(•)R or involves direct binding of RS(•) to face-centered-cubic or hexagonal-close-packed sites. Binding as RS(•) produces large, organizationally chiral domains even when R is achiral, while adatom binding leads to rectangular plane groups that suppress long-range expression of chirality. Binding as RS(•) also inhibits the pitting intrinsically associated with adatom binding, desirably producing more regularly structured SAMs.

  11. Crystal Structure of Aspirin-Acetylated Human Cyclooxygenase-2: Insight into the Formation of Products with Reversed Stereochemistry.

    Science.gov (United States)

    Lucido, Michael J; Orlando, Benjamin J; Vecchio, Alex J; Malkowski, Michael G

    2016-03-01

    Aspirin and other nonsteroidal anti-inflammatory drugs target the cyclooxygenase enzymes (COX-1 and COX-2) to block the formation of prostaglandins. Aspirin is unique in that it covalently modifies each enzyme by acetylating Ser-530 within the cyclooxygenase active site. Acetylation of COX-1 leads to complete loss of activity, while acetylation of COX-2 results in the generation of the monooxygenated product 15(R)-hydroxyeicosatetraenoic acid (15R-HETE). Ser-530 has also been shown to influence the stereochemistry for the addition of oxygen to the prostaglandin product. We determined the crystal structures of S530T murine (mu) COX-2, aspirin-acetylated human (hu) COX-2, and huCOX-2 in complex with salicylate to 1.9, 2.0, and 2.4 Å, respectively. The structures reveal that (1) the acetylated Ser-530 completely blocks access to the hydrophobic groove, (2) the observed binding pose of salicylate is reflective of the enzyme-inhibitor complex prior to acetylation, and (3) the observed Thr-530 rotamer in the S530T muCOX-2 crystal structure does not impede access to the hydrophobic groove. On the basis of these structural observations, along with functional analysis of the S530T/G533V double mutant, we propose a working hypothesis for the generation of 15R-HETE by aspirin-acetylated COX-2. We also observe differential acetylation of COX-2 purified in various detergent systems and nanodiscs, indicating that detergent and lipid binding within the membrane-binding domain of the enzyme alters the rate of the acetylation reaction in vitro.

  12. THE CRYSTAL STRUCTURE OF ASPIRIN ACETYLATED HUMAN CYCLOOXYGENASE-2: INSIGHT INTO THE FORMATION OF PRODUCTS WITH REVERSED STEREOCHEMISTRY

    Science.gov (United States)

    Lucido, Michael J.; Orlando, Benjamin J.; Vecchio, Alex J.; Malkowski, Michael G.

    2016-01-01

    Aspirin and other nonsterroidal anti-inflammatory drugs target the Cyclooxygenase enzymes (COX-1 and COX-2) to block the formation of prostaglandins. Aspirin is unique in that it covalently modifies each enzyme by acetylating Ser-530 within the cyclooxygenase active site. Acetylation of COX-1 leads to complete loss of activity, while acetylation of COX-2 results in the generation of the mono-oxygenated product 15(R)-hydroxyeicosatetraenoic acid (15R-HETE). Ser-530 has also been shown to influence the stereochemistry for oxygen addition into the prostaglandin product. We determined the crystal structures of S530T murine (mu) COX-2, aspirin-acetylated human (hu) COX-2, and huCOX-2 in complex with salicylate to 1.9Å, 2.0Å, and 2.4Å, respectively. The structures reveal that: 1) the acetylated Ser-530 completely blocks access to the hydrophobic groove; 2) the observed binding pose of salicylate is reflective of the enzyme-inhibitor complex prior to acetylation; and 3) the observed Thr-530 rotamer in the S530T muCOX-2 crystal structure does not impede access to the hydrophobic groove. Based on these structural observations, along with functional analysis of the S530T/G533V double mutant, we propose a working hypothesis for the generation of 15R-HETE by aspirin-acetylated COX-2. We also observe differential acetylation of COX-2 purified in various detergent systems and nanodiscs, indicating that detergent and lipid binding within the membrane-binding domain of the enzyme alters the rate of the acetylation reaction in vitro. PMID:26859324

  13. A Quiz on Stereochemistry.

    Science.gov (United States)

    Ghosh, Abhik

    1987-01-01

    Presents five problems on organic stereochemistry in the form of an open-book quiz meant for senior undergraduates and graduate students in chemistry. Provides some acceptable solutions to the problems. (TW)

  14. Total synthesis, assignment of the relative and absolute stereochemistry, and structural reassignment of phostriecin (aka Sultriecin).

    Science.gov (United States)

    Burke, Christopher P; Haq, Nadia; Boger, Dale L

    2010-02-24

    A total synthesis of phostriecin (2), previously known as sultriecin (1), its structural reassignment as a phosphate versus sulfate monoester, and the assignment of its relative and absolute stereochemistry are disclosed herein. Key elements of the work, which provided first the originally assigned sulfate monoester 1 and then the reassigned and renamed phosphate monoester 2, relied on diagnostic (1)H NMR spectroscopic properties of the natural product for the assignment of relative and absolute stereochemistry as well as the subsequent structural reassignment, and a convergent asymmetric total synthesis to provide the unequivocal authentic materials. Key steps of the synthetic approach include a Brown allylation for diastereoselective introduction of the C9 stereochemistry, an asymmetric CBS reduction to establish the lactone C5-stereochemistry, diastereoselective oxidative ring expansion of an alpha-hydroxyfuran to access the pyran lactone precursor, and single-step installation of the sensitive Z,Z,E-triene unit through a chelation-controlled cuprate addition with installation of the C11 stereochemistry. The approach allows ready access to analogues that can now be used to probe important structural features required for protein phosphatase 2A inhibition, the mechanism of action defined herein.

  15. It's all about Me: methyl-induced control of coordination stereochemistry by a flexible tridentate N,C,N' ligand.

    Science.gov (United States)

    Kariuki, Benson M; Platts, James A; Newman, Paul D

    2014-02-21

    A chiral, tridentate, pyridyl-functionalised NHC pro-ligand, S-L(Me)-H[PF₆], has been prepared diastereoselectively via a five step synthesis starting from 1R,3S-diamino-1,2,2-trimethylcyclopentane. The S prefix refers to the stereochemistry of a methyl substituted stereogenic carbon in one of the pyridyl arms which is generated by a stereoselective BH4(-) reduction of an imine precursor. The ligand has been coordinated to Rh(I) and Ir(I) to give trigonal bipyramidal complexes of the type [M(κ(3)-N,C,N'-S-L(Me))(1,5-COD)]PF6 (M = Rh, Ir) as single diastereomers. A combination of spectroscopic and X-ray techniques confirm the stereoselective formation of the thermodynamically preferred endo,endo isomer. Similar reactions with R,S-L(Me)-H[PF₆] gave a mixture of endo,endo-[M(κ(3)-N,C,N'-S-L(Me))(1,5-COD)](+) and exo,exo-[M(κ(3)-N,C,N'-R-L(Me))(1,5-COD)](+). The absolute configuration at the metal is, therefore, solely dictated by the stereochemistry of the single methylpyridyl carbon. The observation of stereoselection extends to the square planar Ni(II) complex [Ni(δ-κ(3)-N,C,N'-S-L(Me))Cl](+) which is isolated as one (δ) of the two possible conformational isomers. DFT studies have been employed to explain the observed stereoselectivity with the configurations observed in the solid state being confirmed as those of lowest energy.

  16. Stereochemistry basic concepts and applications

    CERN Document Server

    Nógrádi, M

    2013-01-01

    Stereochemistry: Basic Concepts and Applications is a three-chapter text that introduces the basic principles and concepts of stereochemistry, as well as its application to organic chemistry application.Chapter 1 describes first the stereochemistry of the ground state, specifically the configuration and conformation of organic compounds, as well as the most important methods for its investigation. This chapter also deals with the kinetics of conformational changes and provides an overview of the so-called ""applied stereochemistry"". Chapter 2 focuses on the analysis of the internal motions of

  17. Assignment of the stereochemistry and anomeric configuration of structurally informative product ions derived from disaccharides: infrared photodissociation of glycosyl-glycolaldehydes in the negative ion mode.

    Science.gov (United States)

    Bendiak, Brad; Fang, Tammy T

    2010-11-01

    Using mass spectrometry in the negative ion mode, m/z 221 ions are frequently observed as product ion substructures derived from reducing disaccharides having 2, 4, or 6 linkages. The ions have been shown to be glycosyl-glycolaldehydes. All 16 stereochemical variants of their pyranosides were prepared and evaluated by infrared photodissociation, in addition to HexNAc-glycolaldehyde variants (m/z 262) of 2-acetamido-2-deoxy-d-glucose and 2-acetamido-2-deoxy-d-galactose. The stereochemistry and anomeric configuration of these ions were differentiated in the gas phase using a Fourier transform ion cyclotron resonance spectrometer with infrared multiphoton dissociation at 10.6 μm. Results were compared to those obtained by collision-induced dissociation. In some cases, differentiation was far preferable using infrared photodissociation; in others, collision-induced dissociation was preferred. Using an instrument that interfaced a linear trap with a Fourier transform ion cyclotron resonance spectrometer, either dissociation technique could be used to optimally discriminate between isomers. With infrared photodissociation, spectral differences were highly statistically significant, even between pairs of isomers having spectra that appeared to be visually somewhat similar (pions). Comparisons among different instruments suggest that physical standards of the stereochemical variants of these ions will be required for their detailed structural assignments in unknowns, as some variation was observed among instruments, both using infrared photodissociation and collision-induced dissociation.

  18. A Simple and Novel Approach to Delineating Stereochemistry of Electrocyclic Reactions

    Science.gov (United States)

    Mandal, Dipak K.

    2012-01-01

    The dynamic stereochemistry of electrocyclic reactions (a class of pericyclic reactions) stems from the operation of either conrotatory (con) or disrotatory (dis) mode of ring-closing and ring-opening processes. Difficulty is often encountered in depicting product stereochemistry resulting from such movements of substituents. A novel, simple,…

  19. Dynamic Stereochemistry: A Simple Approach to Delineating Relative Configuration

    Science.gov (United States)

    Mandal, Dipak K.

    2007-01-01

    A simple approach for delineating the stereochemistry of the products relative to that of the reactants in reactions involving stereogenic centers is addressed. The reaction at the tetrahedral center involves the cleavage of a bond to one of the ligands in the reactant and the resulting new ligand in the product is labeled by affixing prime to the…

  20. Octahedral rhodium(III) complexes as kinase inhibitors: Control of the relative stereochemistry with acyclic tridentate ligands.

    Science.gov (United States)

    Mollin, Stefan; Riedel, Radostan; Harms, Klaus; Meggers, Eric

    2015-07-01

    Octahedral metal complexes are attractive structural templates for the design of enzyme inhibitors as has been demonstrated, for example, with the development of metallo-pyridocarbazoles as protein kinase inhibitors. The octahedral coordination sphere provides untapped structural opportunities but at the same time poses the drawback of dealing with a large number of stereoisomers. In order to address this challenge of controlling the relative metal-centered configuration, the synthesis of rhodium(III) pyridocarbazole complexes with facially coordinating acyclic tridentate ligands was investigated. A strategy for the rapid synthesis of such complexes is reported, the diastereoselectivities of these reactions were investigated, the structure of several complexes were determined by X-ray crystallography, the high kinetic stability of such complexes in thiol-containing solutions was demonstrated in (1)H-NMR experiments, and the protein kinase inhibition ability of this class of complexes was confirmed. It can be concluded that the use of multidentate ligands is currently maybe the most practical strategy to avoid a large number of possible stereoisomers in the course of exploiting octahedral coordination spheres as structural templates for the design of bioactive molecules.

  1. Stereochemistry of the Brivaracetam Diastereoisomers.

    Science.gov (United States)

    Qiu, Shi; Tehrani, Kourosch Abbaspour; Sergeyev, Sergey; Bultinck, Patrick; Herrebout, Wouter; Mathieu, Benoit

    2016-03-01

    The stereochemistry of all four stereoisomers of brivaracetam was determined using vibrational circular dichroism (VCD) spectroscopy. By comparing experimentally obtained VCD spectra and computationally simulated ones, the absolute configurations can be confidently assigned without prior knowledge of their relative stereochemistry. Neither the corrected mean absolute errors analysis of the nuclear magnetic resonance (NMR) data, nor the matching of experimental and calculated infrared spectra allowed the diastereoisomers to be distinguished. VCD spectroscopy itself suffices to establish the absolute configurations of all diastereoisomers. The relative stereochemistry could also be statistically confirmed by matching experimental and computed NMR spectra using the CP3 algorithm. The combination of VCD and NMR is recommended for molecules bearing more than one chiral center, as the relative configurations obtained from NMR serve as an independent check for those established with VCD. Analysis of the calculated VCD spectra reveals that the localized NH2 scissoring mode at around 1600 cm(-1) is characteristic for intramolecular hydrogen bonding, while the orientation of the ethyl group is reflected by the delocalized modes between 1150 and 1050 cm(-1).

  2. Stereochemistry in subcomponent self-assembly.

    Science.gov (United States)

    Castilla, Ana M; Ramsay, William J; Nitschke, Jonathan R

    2014-07-15

    CONSPECTUS: As Pasteur noted more than 150 years ago, asymmetry exists in matter at all organization levels. Biopolymers such as proteins or DNA adopt one-handed conformations, as a result of the chirality of their constituent building blocks. Even at the level of elementary particles, asymmetry exists due to parity violation in the weak nuclear force. While the origin of homochirality in living systems remains obscure, as does the possibility of its connection with broken symmetries at larger or smaller length scales, its centrality to biomolecular structure is clear: the single-handed forms of bio(macro)molecules interlock in ways that depend upon their handednesses. Dynamic artificial systems, such as helical polymers and other supramolecular structures, have provided a means to study the mechanisms of transmission and amplification of stereochemical information, which are key processes to understand in the context of the origins and functions of biological homochirality. Control over stereochemical information transfer in self-assembled systems will also be crucial for the development of new applications in chiral recognition and separation, asymmetric catalysis, and molecular devices. In this Account, we explore different aspects of stereochemistry encountered during the use of subcomponent self-assembly, whereby complex structures are prepared through the simultaneous formation of dynamic coordinative (N → metal) and covalent (N═C) bonds. This technique provides a useful method to study stereochemical information transfer processes within metal-organic assemblies, which may contain different combinations of fixed (carbon) and labile (metal) stereocenters. We start by discussing how simple subcomponents with fixed stereogenic centers can be incorporated in the organic ligands of mononuclear coordination complexes and communicate stereochemical information to the metal center, resulting in diastereomeric enrichment. Enantiopure subcomponents were then

  3. Determination of the Absolute Stereochemistry of Secondary Alcohols: An Advanced Organic Chemistry Experiment for Undergraduate Students.

    Science.gov (United States)

    Bandaranayake, Wickramasinghe M.

    1980-01-01

    Describes experiments which can be completed in five four-hour laboratory sessions, including two synthesis (alpha-phenylbutyric and alpha-phenylbutyric acid anhydride) and determining the absolute stereochemistry of secondary alcohols using the synthetic products. (JN)

  4. SYNTHESIS, STEREOCHEMISTRY AND ANTIMICROBIAL ...

    African Journals Online (AJOL)

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    where C = diameter (in mm)2 of the fungus colony in the control plates after 96 h .... in the spectra of the two ligands is assigned to the ν(CO) stretching vibration. .... active of the tested compounds with a relatively high percentage of inhibition.

  5. Unified Synthesis of 10-Oxygenated Lycopodium Alkaloids: Impact of C10-Stereochemistry on Reactivity.

    Science.gov (United States)

    Saha, Mrinmoy; Li, Xin; Collett, Nathan D; Carter, Rich G

    2016-07-15

    The pronounced impact of the C10 stereochemistry on the successful construction of a polycyclic Lycopodium alkaloid scaffold has been explored. A wide range of reaction conditions and functionality were investigated to control a keto sulfone Michael addition to construct the C7-C12 linkage. An unexpected, overriding impact of the C10 stereochemistry in stereoselectivity and reaction rate in the Michael addition was observed. Furthermore, divergent reactivity of a conformationally accelerated, intramolecular Mannich cyclization based on the C10 stereochemistry was discovered. The successful execution of this synthetic route resulted in the total synthesis of all three known 10-oxygenated Lycopodium alkaloids: 10-hydroxylycopodine, paniculine, and deacetylpaniculine.

  6. Teaching metathesis "simple" stereochemistry.

    Science.gov (United States)

    Fürstner, Alois

    2013-09-20

    Applications of metal-catalyzed olefin metathesis reactions manifested dramatic growth during the late 20th and early 21st centuries, culminating in the 2005 Nobel Prize awarded to three of the pioneers. The standard catalysts developed during that time frame and their descendants have profoundly changed the mindset of the synthetic community, even though they do not provide a handle to control selectivity issues as fundamental as the E/Z geometry of the newly formed double bond. With yet another generation of catalysts in the making that are far superior in this regard, a new wave seems to be building up that is expected to have enormous impact, too. The current state of the art is critically assessed, as are possible alternatives such as the metathesis of triple bonds followed by stereoselective semi-reduction.

  7. Synthesis and stereochemistry of 6-membered ring phosphonates

    Directory of Open Access Journals (Sweden)

    Michael D. Pungente

    2012-03-01

    Full Text Available Background: Organophosphorus compounds have important industrial and biomedical applications as pharmaceutical and agrochemical agents, as well as transition state analogs for the production of monoclonal antibodies. Methods: Two diastereomers of a 6-membered ring, cyclic phenyl phosphonate were synthesized in 8 steps from 1,3-butanediol. Results: The stereochemistry of the diastereomers was elucidated on the basis of H NMR nuclear Overhauser effects (NOE difference experiments. Conclusions: Such cyclic phosphonates may have utility serving as transition state analogs for the production of monoclonal antibodies.

  8. Stereochemistry of substitution at trico-ordinate phosphorus

    DEFF Research Database (Denmark)

    Nielsen, John; Dahl, Otto

    1984-01-01

    and 31P) from reactant and product diastereoisomers have been assigned, and the stereo-chemistry of the substitution reactions have been determined by 31P n.m.r. monitoring. The outcome varies from complete inversion to complete lack of stereoselectivity. During the initial stages many of the non-selective...... reactions proceed with predominant inversion, and most of the results may be interpreted by assuming that the actual substitution step occurs with inversion, and that the lack of stereoselectivity is due to competing isomerizations of products or reactants. Exceptions are certain reactions where the leaving...... group is Cl; these appear to involve a non-selective substitution step....

  9. Stereochemistry of reductive dehalogenation with deuterium gas

    Energy Technology Data Exchange (ETDEWEB)

    Kaspersen, F.M.; Sperling, E.M.

    1986-06-01

    The stereochemistry of reductive debromination and deiodination of 4-haloprolines and 2- or 7-bromo-cholesterols with /sup 2/H/sub 2/ catalyzed by Pd was investigated using /sup 2/H NMR. The reactions are stereoselective but not stereospecific.

  10. Hexuronic acid stereochemistry determination in chondroitin sulfate glycosaminoglycan oligosaccharides by electron detachment dissociation.

    Science.gov (United States)

    Leach, Franklin E; Ly, Mellisa; Laremore, Tatiana N; Wolff, Jeremy J; Perlow, Jacob; Linhardt, Robert J; Amster, I Jonathan

    2012-09-01

    Electron detachment dissociation (EDD) has previously provided stereo-specific product ions that allow for the assignment of the acidic C-5stereochemistry in heparan sulfate glycosaminoglycans (GAGs), but application of the same methodology to an epimer pair in the chondroitin sulfate glycoform class does not provide the same result. A series of experiments have been conducted in which glycosaminoglycan precursor ions are independently activated by electron detachment dissociation (EDD), electron induced dissociation (EID), and negative electron transfer dissociation (NETD) to assign the stereochemistry in chondroitin sulfate (CS) epimers and investigate the mechanisms for product ion formation during EDD in CS glycoforms. This approach allows for the assignment of electronic excitation products formed by EID and detachment products to radical pathways in NETD, both of which occur simultaneously during EDD. The uronic acid stereochemistry in electron detachment spectra produces intensity differences when assigned glycosidic and cross-ring cleavages are compared. The variations in the intensities of the doubly deprotonated (0,2)X(3) and Y(3) ions have been shown to be indicative of CS-A/DS composition during the CID of binary mixtures. These ions can provide insight into the uronic acid composition of binary mixtures in EDD, but the relative abundances, although reproducible, are low compared with those in a CID spectrum acquired on an ion trap. The application of principal component analysis (PCA) presents a multivariate approach to determining the uronic acid stereochemistry spectra of these GAGs by taking advantage of the reproducible peak distributions produced by electron detachment.

  11. Absolute stereochemistry of altersolanol A and alterporriols.

    Science.gov (United States)

    Kanamaru, Saki; Honma, Miho; Murakami, Takanori; Tsushima, Taro; Kudo, Shinji; Tanaka, Kazuaki; Nihei, Ken-Ichi; Nehira, Tatsuo; Hashimoto, Masaru

    2012-02-01

    The absolute stereochemistry of altersolanol A (1) was established by observing a positive exciton couplet in the circular dichroism (CD) spectrum of the C3,C4-O-bis(2-naphthoyl) derivative 10 and by chemical correlations with known compound 8. Before the discussion, the relative stereochemistry of 1 was confirmed by X-ray crystallographic analysis. The shielding effect at C7'-OMe group by C1-O-benzoylation established the relative stereochemical relationship between the C8-C8' axial bonding and the C1-C4/C1'-C4' polyol moieties of alterporriols E (3), an atropisomer of the C8-C8' dimer of 1. As 3 could be obtained by dimerization of 1 in vitro, the absolute configuration of its central chirality elements (C1-C4) must be identical to those of 1. Spectral comparison between the experimental and theoretical CD spectra supported the above conclusion. Axial stereochemistry of novel C4-O-deoxy dimeric derivatives, alterporriols F (4) and G (5), were also revealed by comparison of their CD spectra to those of 2 and 3.

  12. Software product quality control

    CERN Document Server

    Wagner, Stefan

    2013-01-01

    Quality is not a fixed or universal property of software; it depends on the context and goals of its stakeholders. Hence, when you want to develop a high-quality software system, the first step must be a clear and precise specification of quality. Yet even if you get it right and complete, you can be sure that it will become invalid over time. So the only solution is continuous quality control: the steady and explicit evaluation of a product's properties with respect to its updated quality goals.This book guides you in setting up and running continuous quality control in your environment. Star

  13. The Stereochemistry of Biochemical Molecules: A Subject to Revisit

    Science.gov (United States)

    Centelles, Josep J.; Imperial, Santiago

    2005-01-01

    Although Fischer's convention for stereoisomers is useful for simple molecules, the stereochemistry of complex biochemical molecules is often poorly indicated in textbooks. This article reports on errors in stereochemistry of complex hydrosoluble vitamin B12 molecule. Twenty-five popular biochemistry textbooks were examined for their treatment of…

  14. A DSC investigation on the influence of gemini surfactant stereochemistry on the organization of lipoplexes and on their interaction with model membranes.

    Science.gov (United States)

    Aleandri, S; Bonicelli, M G; Giansanti, L; Giuliani, C; Ierino, M; Mancini, G; Martino, A; Scipioni, A

    2012-12-01

    Previous investigations showed that the extent of DNA condensation and the efficiency in the transfection of liposomes formulated with 1,2-dimyristoyl-sn-glycero-phosphocholine and cationic stereomeric gemini surfactants depend heavily on the stereochemistry of the gemini. The influence of the stereochemistry on the interaction of lipoplexes with zwitterionic and anionic cell membrane models was investigated by differential scanning calorimetry to rationalize their different biological behavior. Further, the thermotropic behavior of the corresponding liposomes and of the spontaneous self-assemblies of gemini surfactants in the presence and in the absence of DNA was evaluated to correlate the physicochemical properties of lipoplexes and the stereochemistry of the cationic component. The obtained results show that the stereochemistry of the gemini surfactant controls lipoplexes organization and their mode and kinetic of interaction with different cell membrane models.

  15. Stereochemistry and spectroscopic analysis of bis-Betti base derivatives of 2,3-dihydroxynaphthalene.

    Science.gov (United States)

    Zamani, Mehdi; Shafiee, Mehdi; Keshavarz, Mohammad Hossein

    2016-04-01

    Density functional theory (DFT) was used to study the stereochemistry, thermodynamic stability, and spectra of recently synthesized bis-Betti base derivatives of 2,3-dihydroxynaphthalene obtained through multicomponent reactions of 2,3-dihydroxynaphthalene with aminoisoxazole and benzaldehyde derivatives. The stereochemistry of the products was investigated by theoretically calculating the infrared (IR) and proton nuclear magnetic resonance ((1)H NMR) spectra of the diastereomers and comparing them to the corresponding experimental data. The thermochemical properties of the reactions, including the enthalpy, internal energy, entropy, and Gibbs free energy, were also calculated. The diastereoselectivity of the reactions was estimated from the equilibrium distribution of diastereomers. According to the results, the synthesis of bis-Betti bases is exothermic and accompanied by a decrease in entropy. The energy difference between the diastereomers is quite small, but the Gibbs free energy change for the equilibrium syn anti favors the anti over syn configuration. These results are in good agreement with experimental observations.

  16. Chemical synthesis of the lantibiotic lacticin 481 reveals the importance of lanthionine stereochemistry.

    Science.gov (United States)

    Knerr, Patrick J; van der Donk, Wilfred A

    2013-05-15

    Lantibiotics are a family of antibacterial peptide natural products characterized by the post-translational installation of the thioether-containing amino acids lanthionine and methyllanthionine. Until recently, only a single naturally occurring stereochemical configuration for each of these cross-links was known. The discovery of lantibiotics with alternative lanthionine and methyllanthionine stereochemistry has prompted an investigation of its importance to biological activity. Here, solid-supported chemical synthesis enabled the total synthesis of the lantibiotic lacticin 481 and analogues containing cross-links with non-native stereochemical configurations. Biological evaluation revealed that these alterations abolished the antibacterial activity in all of the analogues, revealing the critical importance of the enzymatically installed stereochemistry for the biological activity of lacticin 481.

  17. Absolute Configuration of (-)-2-(4-Hydroxyphenyl)propionic acid: Stereochemistry of Soy Isoflavone Metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Mihyang; Han, Jaehong [Chung-Ang Univ., Seoul (Korea, Republic of)

    2014-06-15

    We have elucidated stereochemistry of (-)-2-HPPA. Determination of (R)-2-HPPA stereochemistry also provided stereochemical information of genistein metabolism. Considering the stereochemistry of 2-HPPA, the precursor of (R)-2-HPPA should be (R)-6'-hydroxy-O-DMA. Besides, it is clear that only (S)-dihydrogenistein is the possible precursor of (R)-6'-hydroxy-O-DMA. Therefore, genistein metabolism is suggested to follow the same stereochemical pathway like daidzein. Biotransformation of natural products by human intestinal bacteria has recently drawn a significant interest, due to the emerging strong correlation between gut microbiota and human health. Microbial metabolism of natural products by intestinal bacteria in small intestine and colon proceeds the phase I and II xenobiotic metabolisms in the liver. The metabolites were found to exhibit different biological activities, and affect human etiology. For example, many beneficial effects of dietary polyphenols in human health are attributed to the microbial metabolites produced by intestinal bacteria and the modulation of gut microbiota composition.

  18. DAG tales: the multiple faces of diacylglycerol--stereochemistry, metabolism, and signaling.

    Science.gov (United States)

    Eichmann, Thomas Oliver; Lass, Achim

    2015-10-01

    The neutral lipids diacylglycerols (DAGs) are involved in a plethora of metabolic pathways. They function as components of cellular membranes, as building blocks for glycero(phospho)lipids, and as lipid second messengers. Considering their central role in multiple metabolic processes and signaling pathways, cellular DAG levels require a tight regulation to ensure a constant and controlled availability. Interestingly, DAG species are versatile in their chemical structure. Besides the different fatty acid species esterified to the glycerol backbone, DAGs can occur in three different stereo/regioisoforms, each with unique biological properties. Recent scientific advances have revealed that DAG metabolizing enzymes generate and distinguish different DAG isoforms, and that only one DAG isoform holds signaling properties. Herein, we review the current knowledge of DAG stereochemistry and their impact on cellular metabolism and signaling. Further, we describe intracellular DAG turnover and its stereochemistry in a 3-pool model to illustrate the spatial and stereochemical separation and hereby the diversity of cellular DAG metabolism.

  19. Stereochemistry of substitution at trico-ordinate phosphorus

    DEFF Research Database (Denmark)

    Nielsen, John; Dahl, Otto

    1984-01-01

    and 31P) from reactant and product diastereoisomers have been assigned, and the stereo-chemistry of the substitution reactions have been determined by 31P n.m.r. monitoring. The outcome varies from complete inversion to complete lack of stereoselectivity. During the initial stages many of the non......-selective reactions proceed with predominant inversion, and most of the results may be interpreted by assuming that the actual substitution step occurs with inversion, and that the lack of stereoselectivity is due to competing isomerizations of products or reactants. Exceptions are certain reactions where the leaving......A series of reactions of ring-substituted 1,3,2-dioxaphospholanes, 1,3,2-oxazaphospholanes, 1,2-oxaphospholes, and phosphetanes bearing the leaving groups Cl, OR, or NR2 on phosphorus, with the nucleophiles HCl, MeO-, MeOH, PhOH, Me2NH, Et2NH, and [CH 2]5NH have been studied. N.m.r. signals (1H...

  20. Alteration of Polyketide Stereochemistry from anti to syn by a Ketoreductase Domain Exchange in a Type I Modular Polyketide Synthase Subunit.

    Science.gov (United States)

    Eng, Clara H; Yuzawa, Satoshi; Wang, George; Baidoo, Edward E K; Katz, Leonard; Keasling, Jay D

    2016-03-29

    Polyketide natural products have broad applications in medicine. Exploiting the modular nature of polyketide synthases to alter stereospecificity is an attractive strategy for obtaining natural product analogues with altered pharmaceutical properties. We demonstrate that by retaining a dimerization element present in LipPks1+TE, we are able to use a ketoreductase domain exchange to alter α-methyl group stereochemistry with unprecedented retention of activity and simultaneously achieve a novel alteration of polyketide product stereochemistry from anti to syn. The substrate promiscuity of LipPks1+TE further provided a unique opportunity to investigate the substrate dependence of ketoreductase activity in a polyketide synthase module context.

  1. Stereochemistry of organometallic and inorganic compounds

    CERN Document Server

    2012-01-01

    The authors of this fourth volume in the series have reviewed the making and breaking of chemical bonds in a sophisticated manner. In particular, new pressures brought about by environmental concerns, larger demands for the medical and pharmaceutical sectors and economics of the market place are forcing us into demanding greater stereochemical control and better product yields for chemical reactions capable of producing useful products. The chapters are written by leading experts in this area and give excellent overviews of the strengths and weaknesses of the various methodologies.In C

  2. Synthesis, determination of stereochemistry, and evaluation of new bisindole alkaloids from the myxomycete Arcyria ferruginea: an approach for Wnt signal inhibitor.

    Science.gov (United States)

    Kaniwa, Kouken; Arai, Midori A; Li, Xiaofan; Ishibashi, Masami

    2007-08-01

    To determine the stereochemistry of dihydroarcyriarubin C (1), new bisindole alkaloid isolated from the myxomycete Arcyria ferruginea, cis- (2) and trans-dihydroarcyriarubin C (3) were synthesized. Comparison of their NMR characteristics allowed the trans stereochemistry of the natural product to be confirmed. Moreover, the Wnt signal inhibitory activities of 2 and 3 were compared with that of arcyriaflavin C (4), which is a natural product containing a bond between C-2 and C-2'. The cis-dihydroarcyriarubin C (2) showed moderate inhibition of Wnt signal transcription, which suggests that bisindole frameworks might be useful as small-molecule Wnt signal inhibitors.

  3. Relative Stereochemistry of a Diterpene from Salvia cinnabarina

    Directory of Open Access Journals (Sweden)

    Carlo Andrea Mattia

    2007-10-01

    Full Text Available The relative stereochemistry of 3,4-secoisopimara-4(18,7,15-triene-3-oic acid, a diterpenoid with antispasmodic, hypotensive and antibacterial activities isolated from Salvia cinnabarina, was determined by an X-ray diffraction analysis of a single crystal of a suitable crystalline derivative.

  4. An Adventure in Stereochemistry: Alice in Mirror Image Land

    Science.gov (United States)

    Dinan, Frank J.; Yee, Gordon T.

    2004-01-01

    This case is based on an article that considered the problems that would arise if a person were to cross over into a mirror-image environment (Yee 2002). Some of the stereochemistry problems posed in that article are woven into this case study. (Contains 8 figures.)

  5. Prediction of Stereochemistry using Q2MM.

    Science.gov (United States)

    Hansen, Eric; Rosales, Anthony R; Tutkowski, Brandon; Norrby, Per-Ola; Wiest, Olaf

    2016-05-17

    transition metal-catalyzed reactions that are important from both an industrial and an academic perspective. In this Account, we provide an overview of the continued improvement of the prediction of stereochemistry using Q2MM-derived TSFFs using four examples from different stages of development: (i) Pd-catalyzed allylation, (ii) OsO4-catalyzed asymmetric dihydroxylation (AD) of alkenes, (iii) Rh-catalyzed hydrogenation of enamides, and (iv) Ru-catalyzed hydrogenation of ketones. In the current form, correlation coefficients of 0.8-0.9 between calculated and experimental ee values are typical for a wide range of substrate-ligand combinations, and suitable ligands can be predicted for a given substrate with ∼80% accuracy. Although the generation of a TSFF requires an initial effort and will therefore be most useful for widely used reactions that require frequent screening campaigns, the method allows for a rapid virtual screen of large ligand libraries to focus experimental efforts on the most promising substrate-ligand combinations.

  6. ELECTRON DETACHMENT DISSOCIATION OF SYNTHETIC HEPARAN SULFATE GLYCOSAMINOGLYCAN TETRASACCHARIDES VARYING IN DEGREE OF SULFATION AND HEXURONIC ACID STEREOCHEMISTRY.

    Science.gov (United States)

    Leach, Franklin E; Arungundram, Sailaja; Al-Mafraji, Kanar; Venot, Andre; Boons, Geert-Jan; Amster, I Jonathan

    2012-12-15

    Glycosaminoglycan (GAG) carbohydrates provide a challenging analytical target for structural determination due to their polydisperse nature, non-template biosynthesis, and labile sulfate modifications. The resultant structures, although heterogeneous, contain domains which indicate a sulfation pattern or code that correlates to specific function. Mass spectrometry, in particular electron detachment dissociation Fourier transform ion cyclotron resonance (EDD FT-ICR MS), provides a highly sensitive platform for GAG structural analysis by providing cross-ring cleavages for sulfation location and product ions specific to hexuronic acid stereochemistry. To investigate the effect of sulfation pattern and variations in stereochemistry on EDD spectra, a series of synthetic heparan sulfate (HS) tetrasaccharides are examined. Whereas previous studies have focused on lowly sulfated compounds (0.5-1 sulfate groups per disaccharide), the current work extends the application of EDD to more highly sulfated tetrasaccharides (1-2 sulfate groups per disaccharide) and presents the first EDD of a tetrasaccharide containing a sulfated hexuronic acid. For these more highly sulfated HS oligomers, alternative strategies are shown to be effective for extracting full structural details. These strategies inlcude sodium cation replacement of protons, for determining the sites of sulfation, and desulfation of the oligosaccharides for the generation of product ions for assigning uronic acid stereochemistry.

  7. Stereochemistry at the forefront in the design and discovery of novel anti-tuberculosis agents.

    Science.gov (United States)

    Huang, Qingqing; He, Rong; Kozikowski, Alan P

    2011-01-01

    Today, 75% of new drugs introduced to the market are single enantiomers and new techniques in asymmetric synthesis and chiral separation expedites chiral drug discovery and development worldwide. The enantiomers of a chiral drug present unique chemical and pharmacological behaviors in a chiral environment, such as the human body, in which the stereochemistry of chiral drugs determines their pharmacokinetic, pharmacodynamic, and toxicological actions. Thus, it is imperative that only the pure and therapeutically active isomer be prepared and marketed. Tuberculosis (TB), a highly contagious and airborne disease that is caused by infection with Mycobacterium tuberculosis (Mtb), currently represents one of the most threatening health problems globally. The emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB), as well as HIV co-infection along with a lengthy treatment regimen, highlights an urgent need for the development of new anti-TB agents. Currently, new chiral anti-TB agents are being developed from some well-known anti-TB agents, high throughput screening (HTS) hits, and natural products. This review will focus on the reported chiral anti-TB agents together with the clinical importance of their chirality and stereochemistry.

  8. Reinvestigation of the Branimycin Stereochemistry at Position 17-C.

    Science.gov (United States)

    Čikoš, Ana; Triballeau, Nicolas; Hubbard, Paul A; Žiher, Dinko; Stouten, Pieter F W; Doyon, Julien G P-O; Deschrijver, Tiny; Wouters, Johan; Lépine, Renaud H M; Saniere, Laurent

    2016-02-19

    A conformational study of branimycin was performed using single-crystal X-ray crystallography to characterize the solid-state form, while a combination of NMR spectroscopy and molecular modeling was employed to gain information about the solution structure. Comparison of the crystal structure with its solution counterpart showed no significant differences in conformation, confirming the relative rigidity of the tricyclic system. However, these experiments revealed that the formerly proposed stereochemistry of branimycin at 17-C should be revised.

  9. Stereochemistry of bistricyclic aromatic enes and related polycyclic systems.

    Science.gov (United States)

    Biedermann, P Ulrich; Agranat, Israel

    2014-01-01

    Bistricyclic aromatic enes (BAEs) and related polycyclic systems are a class of molecular materials that display a rich variety of conformations, dynamic stereochemistry and switchable chirality, color, and spectroscopic properties. This is due to the a subtle interplay of the inherent preference for planarity of aromatic systems and the competing necessity of non-planarity due to intramolecular overcrowding in the fjord regions built into the general molecular structure of BAEs. The conformational, dynamic, and spectroscopic properties may be designed and fine-tuned, e.g., by variation of the bridging groups X and Y, the overcrowding in the fjord regions, extensions of the aromatic system, or other modifications of the general BAE structure, based on the fundamental understanding of the structure-property relationships (SPR). The present review provides an analysis of the conformational spaces and the dynamic stereochemistry of overcrowded bistricyclic aromatic enes applying fundamental symmetry considerations. The symmetry analysis presented here allows deeper insight into the conformations, chirality, and the mechanisms of the dynamic stereochemistry, and will be instrumental in future computational studies.

  10. Handling of tautomerism and stereochemistry in compound registration.

    Science.gov (United States)

    Gobbi, Alberto; Lee, Man-Ling

    2012-02-27

    Automated registration of compounds from external sources is necessitated by the numerous compound acquisitions from vendors and by the increasing number of collaborations with external partners. A prerequisite for automating compound registration is a robust module for determining the structural novelty of the input structures. Any such tool needs to be able to take uncertainty about stereochemistry into account and to identify tautomeric forms of the same compound. It also needs to validate structures for potential mistakes in connectivity and stereochemistry. Genentech has implemented a Structure Normalization Module based on toolkits offered by OpenEye Scientific Software. The module is incorporated in a graphical application for single compound registration and in scripts for bulk registration. It is also used for checking compounds submitted by our collaborators via partner-specific Internet sites. The Genentech Structure Normalization Module employs the widely used V2000 molfile format to accommodate structures received from a wide variety of sources. To determine how much information is known about the stereochemistry of each compound, the module requires a separate stereochemical assignment. A structural uniqueness check is performed by comparing the canonical SMILES of a standard tautomer. This paper offers a discussion of the steps taken to validate the chemical structure and generate the canonical SMILES of the standard tautomer. It also describes the integration of the validation module in compound registration pathways.

  11. Production control system specified quality sausage products

    Directory of Open Access Journals (Sweden)

    A. V. Tokarev

    2016-01-01

    Full Text Available The problem of management of production target in technological system of production of sausages of the set quality is considered in article. Decomposition of technological system is considered. Functions of management are allocated: formation of an optimum compounding of forcemeat, expert analysis of a compounding, laboratory analysis of a compounding and its statement. Information technology of interaction of these functions is offered. The mathematical problem definition of finding of an optimum compounding meat product with use of possible substitutes of ingredients is presented. This mathematical problem is a classical linear programming problem whose solution has the standard program. Since the manufacture of the finished product are various nonlinear effects are taken into account at the present time it is practically impossible, the methodology provided in this operation "Expert analysis of the formulation" and "Laboratory analysis of the finished product." An example of calculating the optimum alternative base recipe "Sausages “Viennese with cheese”" TS 9213-010-40155161-2002. For an alternative formulation demands were made at a cost of meat, the ingredient composition, as well as the final product organoleptic and physic-chemical indicators should comply with regulatory requirements "Sausages “Viennese with cheese”" TS 9213-010-40155161-2002. Indicator acid activity (pH calculated stuffing formulation should be in the range 6.0-6.3. As a partial replacement for the main raw material have been proposed acceptable substitutes. It was necessary to calculate on the basis of the formulation "Sausages “Viennese with cheese”" TS 9213-010-40155161-2002 optimal price and quality alternative formulation. As a result of depreciation of the value of alternative stuffing recipe was 14,5 % when all of the restrictions on the consumer properties. The proposed information technology implemented in the software package "Multi

  12. Volatile products controlling Titan's tholins production

    KAUST Repository

    Carrasco, Nathalie

    2012-05-01

    A quantitative agreement between nitrile relative abundances and Titan\\'s atmospheric composition was recently shown with a reactor simulating the global chemistry occurring in Titan\\'s atmosphere (Gautier et al. [2011]. Icarus, 213, 625-635). Here we present a complementary study on the same reactor using an in situ diagnostic of the gas phase composition. Various initial N 2/CH 4 gas mixtures (methane varying from 1% to 10%) are studied, with a monitoring of the methane consumption and of the stable gas neutrals by in situ mass spectrometry. Atomic hydrogen is also measured by optical emission spectroscopy. A positive correlation is found between atomic hydrogen abundance and the inhibition function for aerosol production. This confirms the suspected role of hydrogen as an inhibitor of heterogeneous organic growth processes, as found in Sciamma-O\\'Brien et al. (Sciamma-O\\'Brien et al. [2010]. Icarus, 209, 704-714). The study of the gas phase organic products is focussed on its evolution with the initial methane amount [CH 4] 0 and its comparison with the aerosol production efficiency. We identify a change in the stationary gas phase composition for intermediate methane amounts: below [CH 4] 0=5%, the gas phase composition is mainly dominated by nitrogen-containing species, whereas hydrocarbons are massively produced for [CH 4] 0>5%. This predominance of N-containing species at lower initial methane amount, compared with the maximum gas-to solid conversion observed in Sciamma-O\\'Brien et al. (2010) for identical methane amounts confirms the central role played by N-containing gas-phase compounds to produce tholins. Moreover, two protonated imines (methanimine CH 2NH and ethanamine CH 3CHNH) are detected in the ion composition in agreement with Titan\\'s INMS measurements, and reinforcing the suspected role of these chemical species on aerosol production. © 2012 Elsevier Inc.

  13. Revised stereochemistry of ceramide-trafficking inhibitor HPA-12 by X-ray crystallography analysis.

    Science.gov (United States)

    Ueno, Masaharu; Huang, Yi-Yong; Yamano, Akihito; Kobayashi, Shū

    2013-06-07

    In response to Berkeš's report revising the stereochemistry of HPA-12, an important ceramide-trafficking inhibitor that was discovered and synthesized and its stereochemistry determined in 2001, the synthesis and the stereochemistry were reinvestigated. A large-scale synthetic method for HPA-12 based on a Zn-catalyzed asymmetric Mannich-type reaction in water was developed. Single crystals of HPA-12 for X-ray crystallographic analysis were obtained from ethyl propionate/n-hexane, and the stereochemistry was definitely determined to be 1R,3S, consistent with Berkeš's revised structure.

  14. Introduction of the (-)-berkelic acid side chain and assignment of the C-22 stereochemistry.

    Science.gov (United States)

    Wu, Xiaoxing; Zhou, Jingye; Snider, Barry B

    2009-08-21

    A Kiyooka aldol condensation of an aldehyde with a trimethylsilyl ketene acetal and the oxazaborolidinone prepared from N-Ts-(S)-valine gives two of the four possible aldol adducts, which were oxidized and deprotected to complete the synthesis of (-)-berkelic acid and (-)-22-epi-berkelic acid. This synthesis establishes the absolute stereochemistry and assigns the stereochemistry at C-22. A biosynthetic pathway is proposed that is consistent with the known absolute stereochemistry at the quaternary carbon of spiciferone A, spicifernin, and berkelic acid and provides a simple explanation for the differing stereochemistry at C-18 and C-19 of spicifernin and berkelic acid.

  15. Optogenetic control of ROS production

    Directory of Open Access Journals (Sweden)

    Andrew P. Wojtovich

    2014-01-01

    Full Text Available Reactive Oxygen Species (ROS are known to cause oxidative damage to DNA, proteins and lipids. In addition, recent evidence suggests that ROS can also initiate signaling cascades that respond to stress and modify specific redox-sensitive moieties as a regulatory mechanism. This suggests that ROS are physiologically-relevant signaling molecules. However, these sensor/effector molecules are not uniformly distributed throughout the cell. Moreover, localized ROS damage may elicit site-specific compensatory measures. Thus, the impact of ROS can be likened to that of calcium, a ubiquitous second messenger, leading to the prediction that their effects are exquisitely dependent upon their location, quantity and even the timing of generation. Despite this prediction, ROS signaling is most commonly intuited through the global administration of chemicals that produce ROS or by ROS quenching through global application of antioxidants. Optogenetics, which uses light to control the activity of genetically-encoded effector proteins, provides a means of circumventing this limitation. Photo-inducible genetically-encoded ROS-generating proteins (RGPs were originally employed for their phototoxic effects and cell ablation. However, reducing irradiance and/or fluence can achieve sub-lethal levels of ROS that may mediate subtle signaling effects. Hence, transgenic expression of RGPs as fusions to native proteins gives researchers a new tool to exert spatial and temporal control over ROS production. This review will focus on the new frontier defined by the experimental use of RGPs to study ROS signaling.

  16. Total Syntheses of (+)-Grandilodine C and (+)-Lapidilectine B and Determination of their Absolute Stereochemistry.

    Science.gov (United States)

    Nakajima, Masaya; Arai, Shigeru; Nishida, Atsushi

    2016-03-01

    Enantioselective total syntheses of the Kopsia alkaloids (+)-grandilodine C and (+)-lapidilectine B were accomplished. A key intermediate, spirodiketone, was synthesized in 3 steps and converted into the chiral enone by enantioselective deprotonation followed by oxidation with up to 76 % ee. Lactone formation was achieved through stereoselective vinylation followed by allylation and ozonolysis. The total synthesis of (+)-grandilodine C was achieved by palladium-catalyzed intramolecular allylic amination and ring-closing metathesis to give 8- and 5-membered heterocycles, respectively. Selective reduction of a lactam carbonyl gave (+)-lapidilectine B. The absolute stereochemistry of both natural products was thereby confirmed. These syntheses enable the scalable preparation of the above alkaloids for biological studies.

  17. Antibacterial adhesion of borneol-based polymer via surface chiral stereochemistry.

    Science.gov (United States)

    Luo, Lingqiong; Li, Guofeng; Luan, Di; Yuan, Qipeng; Wei, Yen; Wang, Xing

    2014-01-01

    During its adhesion on external surfaces, a cell exhibits obvious inclination to different molecular chirality, which encourages us to develop a new type of antibacterial material catering to the "chiral taste" of bacteria. On the basis of the natural product borneol (a camphane-type bicyclic monoterpene), a series of borneol-based polymer, polyborneolacrylate (PBA), was successfully prepared and showed superior antibacterial adhesion properties resulting from the borneol isomers on material surface. The results of this study reveal that bacteria simply dislike this type of stubborn surface of PBA, and the PBA surface stereochemistry contributes to the interfacial antibacterial activities. The PBA polymers were evaluated as noncytotoxic and can be simply synthesized, demonstrating their great potential for biomedical applications.

  18. Development of a Web-Based, Student-Centered Stereochemistry Tutorial

    Science.gov (United States)

    Burrmann, Nicola J.; Moore, John W.

    2013-01-01

    A Web-based stereochemistry tutorial is described that details the core definitions and structural representations of stereochemistry in an organic chemistry course. The Cahn-Ingold-Prelog rules and their application for assigning "R" and "S" orientations to stereocenters and "E" and "Z" orientations to…

  19. Total synthesis and absolute stereochemistry of the proteasome inhibitors cystargolides A and B.

    Science.gov (United States)

    Tello-Aburto, Rodolfo; Hallada, Liam P; Niroula, Doleshwar; Rogelj, Snezna

    2015-10-28

    The absolute stereochemistry of the cystargolides was determined by total synthesis. Evaluation of synthetic cystargolides and derivatives showed that the natural (2S,3R) stereochemistry is essential for activity. Moreover, benzyl esters (-)-10 and (-)-15 were found to be about 100 times more potent, and to selectively kill MCF-7 cancerous cells.

  20. On the Stereochemistry of the Kulinkovich Cyclopropanation of Nitriles

    Science.gov (United States)

    Astashko, Dmitry; Lee, Hyung Goo; Bobrov, Denis N.; Cha, Jin K.

    2009-01-01

    The stereochemistry of the Kulinkovich cyclopropanation of nitriles with alkenes has been examined by employing (E)-disubstituted alkenes and deuterium-labeled homoallylic alcohols as a stereochemical probe. An intramolecular cyclopropanation proceeds with preservation of the olefin configuration. On the other hand, intermolecular counterparts occur with both preservation and reversal of the olefin configuration, which corresponds to retention and inversion of configuration at the Ti–C bond, respectively, in the cyclopropane-forming step. These uncommon stereochemical outcomes contrast with that of the Kulinkovich cyclopropanation of tertiary amides. PMID:19527011

  1. Stereochemistry of enzymatic water addition to C=C bonds.

    Science.gov (United States)

    Chen, Bi-Shuang; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    Water addition to carbon-carbon double bonds using hydratases is attracting great interest in biochemistry. Most of the known hydratases are involved in primary metabolism and to a lesser extent in secondary metabolism. New hydratases have recently been added to the toolbox, both from natural sources or artificial metalloenzymes. In order to comprehensively understand how the hydratases are able to catalyse the water addition to carbon-carbon double bonds, this review will highlight the mechanistic and stereochemical studies of the enzymatic water addition to carbon-carbon double bonds, focusing on the syn/anti-addition and stereochemistry of the reaction.

  2. Development of Production Control in Small Batch Production

    Directory of Open Access Journals (Sweden)

    Németh Péter

    2016-01-01

    Full Text Available Our aim with this paper is to develop a new performance measurement and control system for small batch production in the automotive industry. For this reason, we present our previous research results for warehouse performance measurement and adopt its methodology to production control. The proposed method is based on artificial intelligence (neural networks.

  3. Robust Planning and Control Using Intelligent Products

    NARCIS (Netherlands)

    Meyer, Gerben; Wortmann, Johan; David, Esther; Gerding, Enrico; Sarne, David; Shehory, Onn

    2010-01-01

    The advances in production planning and control in the last decades have confirmed the centralized nature of the planning function. However, centralization has disadvantages when quick response to local production problems is required. Therefore, renewed interest in decentralized approaches emerges.

  4. Asymmetric aza-[2,3]-Wittig sigmatropic rearrangements: chiral auxiliary control and formal asymmetric synthesis of (2S, 3R, 4R)-4-hydroxy-3-methylproline and (-)-kainic acid.

    Science.gov (United States)

    Anderson, James C; O'Loughlin, Julian M A; Tornos, James A

    2005-08-07

    A survey of 16 different chiral auxiliaries and a variety of strategies found that an (-)-8-phenylmenthol ester of a glycine derived migrating group can control the absolute stereochemistry of aza-[2,3]-Wittig sigmatropic rearrangements with diastereoselectivities of ca. 3 : 1 with respect to the auxiliary. In two specific examples, ca. 50% yields of enantiomerically pure products were obtained after chromatographic purification. These were synthetically manipulated with no erosion of stereochemistry into intermediates that completed formal asymmetric syntheses of (+)-HyMePro and (-)-kainic acid.

  5. The effect of stereochemistry on the biological activity of natural phytotoxins, fungicides, insecticides and herbicides.

    Science.gov (United States)

    Evidente, Antonio; Cimmino, Alessio; Andolfi, Anna

    2013-02-01

    Phytotoxins are secondary microbial metabolites that play an essential role in the development of disease symptoms induced by fungi on host plants. Although phytotoxins can cause extensive-and in some cases devastating-damage to agricultural crops, they can also represent an important tool to develop natural herbicides when produced by fungi and plants to inhibit the growth and spread of weeds. An alternative strategy to biologically control parasitic plants is based on the use of plant and fungal metabolites, which stimulate seed germination in the absence of the host plant. Nontoxigenic fungi also produce bioactive metabolites with potential fungicide and insecticide activity, and could be applied for crop protection. All these metabolites represent important tools to develop eco-friendly pesticides. This review deals with the relationships between the biological activity of some phytotoxins, seed germination stimulants, fungicides and insecticides, and their stereochemistry.

  6. Natural polyprenylated benzophenones: keto-enol tautomerism and stereochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Felipe T.; Cruz Junior, Jose W.; Doriguetto, Antonio C. [Universidade Federal de Alfenas, MG (Brazil). Dept. de Ciencias Exatas. Lab. de Cristalografia]. E-mail: doriguetto@unifal-mg.edu.br; Derogis, Priscilla B.M.C.; Santos, Marcelo H. dos; Veloso, Marcia P. [Universidade Federal de Alfenas, MG (Brazil). Dept. de Ciencias Exatas. Lab. de Fitoquimica e Quimica Medicinal; Ellena, Javier [Universidade de Sao Paulo, Sao Carlos, SP (Brazil). Inst. de Fisica

    2007-07-01

    The keto-enol tautomerism and stereochemistry study of a HIV-inhibitory natural benzophenone, (1R,5R,7R,8S)-(+)-3-(10-(3,4-dihydroxyphenyl)-10-hydroxymethylene) -8-methyl-1,5,7-tris(3-methyl-2-butenyl)-8-(4-methyl-3-pentenyl)-bicyclo [3.3.1]nonane-2,4,9-trione (a), isolated from Garcinia brasiliensis seeds is presented. The crystal structure of (a), which is also know as guttiferona A, was determined by X-ray diffraction and its intra and inter-molecular geometries discussed and compared with two analogue natural benzophenones: clusianone and epiclusianone. In (a), the hydroxyl H atom from enolizable 2,4,10-trione moiety is linked in the oxygen atom bonded to 10-(3,4-dihydroxyphenyl)methylene group, in opposition to the related natural benzophenones, where this analogue H-atom is placed in different O-atoms from bicyclo[3.3.1]nonane ring system. Such behaviour can be explained by the presence of aromatic OH6 group in (a) that origins a further delocalized resonance path along of 3,4-dihydroxyphenyl- C10-OH2 group. In addition, the (a) stereochemistry around C7 atom is compared with known structures of clusianone and epiclusianone and the influence from configuration in this chiral Catom to structural features found in the enolizable system is proposed. (author)

  7. Avenolide, a Streptomyces hormone controlling antibiotic production in Streptomyces avermitilis.

    Science.gov (United States)

    Kitani, Shigeru; Miyamoto, Kiyoko T; Takamatsu, Satoshi; Herawati, Elisa; Iguchi, Hiroyuki; Nishitomi, Kouhei; Uchida, Miho; Nagamitsu, Tohru; Omura, Satoshi; Ikeda, Haruo; Nihira, Takuya

    2011-09-27

    Gram-positive bacteria of the genus Streptomyces are industrially important microorganisms, producing >70% of commercially important antibiotics. The production of these compounds is often regulated by low-molecular-weight bacterial hormones called autoregulators. Although 60% of Streptomyces strains may use γ-butyrolactone-type molecules as autoregulators and some use furan-type molecules, little is known about the signaling molecules used to regulate antibiotic production in many other members of this genus. Here, we purified a signaling molecule (avenolide) from Streptomyces avermitilis--the producer of the important anthelmintic agent avermectin with annual world sales of $850 million--and determined its structure, including stereochemistry, by spectroscopic analysis and chemical synthesis as (4S,10R)-10-hydroxy-10-methyl-9-oxo-dodec-2-en-1,4-olide, a class of Streptomyces autoregulator. Avenolide is essential for eliciting avermectin production and is effective at nanomolar concentrations with a minimum effective concentration of 4 nM. The aco gene of S. avermitilis, which encodes an acyl-CoA oxidase, is required for avenolide biosynthesis, and homologs are also present in Streptomyces fradiae, Streptomyces ghanaensis, and Streptomyces griseoauranticus, suggesting that butenolide-type autoregulators may represent a widespread and another class of Streptomyces autoregulator involved in regulating antibiotic production.

  8. Complete stereochemistry and preliminary structure-activity relationship of rakicidin A, a hypoxia-selective cytotoxin from Micromonospora sp.

    Science.gov (United States)

    Oku, Naoya; Matoba, Shouhei; Yamazaki, Yohko Momose; Shimasaki, Ryoko; Miyanaga, Satoshi; Igarashi, Yasuhiro

    2014-11-26

    The complete stereochemistry of rakicidin A, a hypoxia-selective cytotoxin produced by Micromonospora sp., was unambiguously established by extensive chemical degradation and derivatization studies. During the PGME derivatization-based configurational analysis of 3-hydroxy-2,4,16-trimethylheptadecanoic acid, an irregular Δδ distribution was observed, which necessitated further acylation of the 3-hydroxy group to resolve the inconsistency. A hydrogenated derivative of rakicidin A, its ring-opened product, and two congeners with different alkyl chain lengths were tested for hypoxia-selective cytotoxicity. The results indicated that both the conjugated diene unit and appropriate chain length are essential for the unique activity of rakicidin A.

  9. Automatic control algorithm effects on energy production

    Science.gov (United States)

    Mcnerney, G. M.

    1981-01-01

    A computer model was developed using actual wind time series and turbine performance data to simulate the power produced by the Sandia 17-m VAWT operating in automatic control. The model was used to investigate the influence of starting algorithms on annual energy production. The results indicate that, depending on turbine and local wind characteristics, a bad choice of a control algorithm can significantly reduce overall energy production. The model can be used to select control algorithms and threshold parameters that maximize long term energy production. The results from local site and turbine characteristics were generalized to obtain general guidelines for control algorithm design.

  10. Analysis of stereochemistry and biosynthesis of epicatechin in tea plants by chiral phase high performance liquid chromatography.

    Science.gov (United States)

    Qian, Yumei; Zhao, Xianqian; Zhao, Lei; Cui, Lilan; Liu, Li; Jiang, Xiaolan; Liu, Yajun; Gao, Liping; Xia, Tao

    2015-12-01

    Tea (Camellia sinensis) is rich in flavan-3-ols (catechins), especially epicatechin (EC), which is the predominant extension unit of polymeric proanthocyanidins (PAs). However, studies assessing EC's stereochemistry are scarce. Here, a high performance liquid chromatography column using amylose tris-(3, 5-dimethylphenylcarbamate) immobilized on silica-gel as chiral stationary phases (CSPs) was applied to explore its stereochemistry and biosynthetic pathway in tea plants. The results revealed (-)-epicatechin [(-)-EC] was the predominant di-hyroxy-non-galloylated-catechins, while (+)-epicatechin [(+)-EC] was not detected. Interestingly, (-)-EC was the only product obtained from cyanidin using the partially purified native C. sinensis anthocyanidin reductase (CsANR) in the presence of reduction nicotinamide adenine dinucleotide phosphate (NADPH); meanwhile, (+)-EC was the main product using recombinant CsANR in the same conditions. In addition, (-)-EC could be obtained from (+)-catechin [(+)-C] using recombinant CsANR, which displayed C3-epimerase activity in the presence of oxidation nicotinamide adenine dinucleotide phosphate (NADP(+)). But the partially purified native CsANR did not possess this function. Finally, (-)-EC could result from the de-gallate acid reaction of epicatechin gallate (ECG) catalyzed by a novel partially purified native galloylated catechins hydrolase (GCH) from tea leaves. In summary, (-)-EC is likely the product of native protein from the tea plants, and (+)-EC is only produced in a reaction catalyzed by recombinant CsANR in vitro.

  11. Relationships between the stereochemistry and biological activity of fungal phytotoxins.

    Science.gov (United States)

    Evidente, Antonio; Andolfi, Anna; Cimmino, Alessio

    2011-10-01

    Toxins produced by phytopathogenic fungi assume great importance because of their involvement in several plant diseases. Although such pathogens are known to have seriously damaged crops, forest, and environmental resources, they represent a very important tool to develop new environmentally friendly herbicides and fungicides. This review deals with the relationships between the biological activity of some phytotoxins produced by pathogenic fungi for major forest plants and for damaging weeds and their stereochemistry. In particular, the methods used to determine their relative and/or absolute configuration will be illustrated. These include the application of Mosher's and Murata's methods, X-ray diffractometric analysis, circular dichroism, and the use of computational methods to determine the theoretical optical rotatory power as well as the CD spectrum. The importance of determining the absolute configuration to achieve the total synthesis of some phytotoxins, interesting for their potential practical application, is also discussed.

  12. An Improved Production Activity Control Architecture for Shop Floor Control

    Institute of Scientific and Technical Information of China (English)

    SHAHIDIkramullahButt; SUNHou-fang; HAMIDUllahKhanNiazi

    2005-01-01

    This paper presents a further improved Production Activity Control Architecture to deal with the complexity of information by creating Sub-Producers and Sub-Movers which will not only give a better control at workstation level but also reduce load on the Dispatcher. It also makes an analysis of the basic and improved PAC (Production Activity Control) Architecture in the Control System for Integrated Manufacturing. The PAC Architecture and the improvement will further enhance the flexibility and adaptability of the architecture in the ever changing environment of the Shop Floor Control (SFC) Systems.

  13. Study of the Stereochemistry and Oxidation Mechanism of Plant Polyphenols, Assisted by Computational Chemistry.

    Science.gov (United States)

    Matsuo, Yosuke

    2017-01-01

     In recent years, plant polyphenols have attracted great attention due to their wide range of biological activities. Certain kinds of polyphenols have complex structures; therefore, it is difficult to elucidate their total structure, including stereochemistry. In this study, we reinvestigated the stereostructures of two major C-glycosidic ellagitannins contained in Quercus plants, vescalagin and castalagin, and revised their stereostructures based on theoretical calculations of spectroscopic data. We also determined the structures of quercusnins A and B, isolated from the sapwood of Quercus crispula, based on theoretical calculations of NMR data. The oxidation mechanism of polyphenols has not been entirely elucidated. Therefore, we have also studied the oxidation mechanism of tea catechins during black tea production. Our investigation of the oxidation mechanism of black tea pigment theaflavins revealed that the difference in the position of the galloyl ester affords different oxidation products of theaflavins. In addition, oxidation products of pyrogallol-type catechins could be classified into three types-dehydrotheasinensins, theacitrins, and proepitheaflagallins; their detailed production and degradation mechanisms were also examined.

  14. Van't Hoff, Le Bel, and the Development of Stereochemistry: A Reassessment.

    Science.gov (United States)

    Grossman, Robert B.

    1989-01-01

    Shows that two theories of stereochemistry were very different theories, grounded in different assumptions and were intended to explain different phenomena. Presents the original theories and later developments which caused a blending of the theories. (Author/MVL)

  15. Microbiological Quality Control of Probiotic Products

    OpenAIRE

    Astashkina, Anna Pavlovna; Khudyakova, L. I.; Kolbysheva, Yuliya Vladimirovna

    2014-01-01

    Microbiological quality control of probiotic products such as Imunele, Dannon, Pomogayka showed that they contain living cultures of the Lactobacillus Bifidobacterium genus in the amount of 107 CFU/ml, which corresponds to the number indicated on the label of products. It is identified that the survival rate of test-strains cultured with pasteurized products does not exceed 10%. The cell concentration of target-microorganisms was reduced by 20-45% after the interaction with living probiotic b...

  16. Asymmetric total synthesis of (-)-lundurine B and determination of its absolute stereochemistry.

    Science.gov (United States)

    Nakajima, Masaya; Arai, Shigeru; Nishida, Atsushi

    2015-04-01

    A total synthesis of the Kopsia tenuis alkaloid (-)-lundurine B has been achieved. A quaternary chiral carbon has been created by an asymmetric deprotonation using a symmetric spiro cyclohexanone intermediate with a chiral lithium amide. The hexacyclic skeleton was sequentially constructed through metal-mediated reactions. The absolute stereochemistry of intermediate 5 has been unambiguously established by X-ray crystallographic analysis. This is the first description of the absolute stereochemistry of Kopsia tenuis alkaloids based on chemical synthesis.

  17. Absolute Stereochemistry of 1,2-Diols from Lipids of Thermomicrobia.

    Science.gov (United States)

    Lagutin, Kirill; Wong, Herbert; Vyssotski, Mikhail; MacKenzie, Andrew

    2016-03-01

    1,2-Diol based phospholipids are a well-known feature of bacteria from the class Thermomicrobia. Since these bacteria contain only lipids with an alkyldiol-1-phosphate backbone instead of sn-glycero-3-phosphate, it is important to elucidate the stereochemistry of the 1,2-diols. We have studied the absolute stereochemistry of long-chain 1,2-diols isolated from Thermorudis pharmacophila (formerly known as Thermomicrobia sp. WKT50.2) by nuclear magnetic resonance (NMR) using α-methoxyphenylacetic acid (MPA). Low-temperature (-60 °C) NMR of bis-(R)-MPA ester showed (R) stereochemistry of the 1,2-diols. This is the first report concerning the stereochemistry of natural 1,2-diols, which replace the glyceride moiety in phospholipids. The (R) stereochemistry of the diols is expected as it is the same configuration as for the common bacterial lipid backbone-sn-glycero-3-phosphate. This is the first application of low-temperature NMR of a single MPA derivative for assignment of stereochemistry of natural 1,2-diols. The results were confirmed by the comparison of NMR data with bis-(R)-MPA ester of (R) and rac-1,2-octanediol.

  18. Goniometer Control System for Coherent Bremsstrahlung Production

    Science.gov (United States)

    Acousta, V. M.

    2002-08-01

    A system for the generation of a high-intensity, quasi-monochromatic photon beam is discussed. The theory behind coherent bremsstrahlung photon beam production is analyzed and developed. The mechanics of a goniometer control system are presented. The software developed for remote control of the goniometer is also discussed. Finally, the results from various performance measurements are included.

  19. Network-based production quality control

    Science.gov (United States)

    Kwon, Yongjin; Tseng, Bill; Chiou, Richard

    2007-09-01

    This study investigates the feasibility of remote quality control using a host of advanced automation equipment with Internet accessibility. Recent emphasis on product quality and reduction of waste stems from the dynamic, globalized and customer-driven market, which brings opportunities and threats to companies, depending on the response speed and production strategies. The current trends in industry also include a wide spread of distributed manufacturing systems, where design, production, and management facilities are geographically dispersed. This situation mandates not only the accessibility to remotely located production equipment for monitoring and control, but efficient means of responding to changing environment to counter process variations and diverse customer demands. To compete under such an environment, companies are striving to achieve 100%, sensor-based, automated inspection for zero-defect manufacturing. In this study, the Internet-based quality control scheme is referred to as "E-Quality for Manufacturing" or "EQM" for short. By its definition, EQM refers to a holistic approach to design and to embed efficient quality control functions in the context of network integrated manufacturing systems. Such system let designers located far away from the production facility to monitor, control and adjust the quality inspection processes as production design evolves.

  20. Stereoselective Synthesis of 8,12-Furanoeudesmanes from Santonin. Absolute Stereochemistry of Natural Furanoeudesma-1,3-diene and Tubipofurane.

    Science.gov (United States)

    Blay, Gonzalo; Cardona, Luz; García, Begoña; Pedro, José R.; Sánchez, Juan J.

    1996-05-31

    Ketobutenolide 3, easily obtained from santonin (1), has been transformed into two natural furanoeudesmanes 4 and 5, isolated from Commiphora molmol and Tubipora musica, respectively. trans- And cis-decalin systems were obtained by stereoselective reduction of the C(4)-C(5) double bond in 3 in the following way: hydrogenation of 3 over Pd/C followed by acidic treatment gave the cis isomer 10 as the major product; selective hydrogenation of the C(1)-C(2) double bond with the Wilkinson's catalyst followed by reduction with NaTeH yielded mainly the trans isomer 9. Compounds 9 and 10 were transformed into 4 and 5 in parallel sequences. Optical rotation and CD measurements of the synthetic products revealed that the stereochemistry of both natural products should be revised to their enantiomeric form.

  1. A bacterial tyrosine aminomutase proceeds through retention or inversion of stereochemistry to catalyze its isomerization reaction.

    Science.gov (United States)

    Wanninayake, Udayanga; Walker, Kevin D

    2013-07-31

    β-Amino acids are biologically active compounds of interest in medicinal chemistry. A class I lyase-like family of aminomutases isomerizes (S)-α-arylalanines to the corresponding β-amino acids by exchange of the NH2/H pair. This family uses a 3,5-dihydro-5-methylidene-4H-imidazol-4-one (MIO) group within the active site to initiate the reaction. The absolute stereochemistry of the product is known for an MIO-dependent tyrosine aminomutase from Chondromyces crocatus (CcTAM) that isomerizes (S)-α-tyrosine to (R)-β-tyrosine. To evaluate the cryptic stereochemistry of the CcTAM mechanism, (2S,3S)-[2,3-(2)H2]- and (2S,3R)-[3-(2)H]-α-tyrosine were stereoselectively synthesized from unlabeled (or [(2)H]-labeled) (4'-hydroxyphenyl)acrylic acids by reduction with D2 (or H2) gas and a chiral Rh-Prophos catalyst. GC/EIMS analysis of the [(2)H]-β-tyrosine biosynthesized by CcTAM revealed that the α-amino group was transferred to Cβ of the phenylpropanoid skeleton with retention of configuration. These labeled substrates also showed that the pro-(3S) proton exchanges with protons from the bulk media during its migration to Cα during catalysis. (1)H- and (2)H NMR analyses of the [(2)H]-β-tyrosine derived from (2S)-[3,3-(2)H2]-α-tyrosine by CcTAM catalysis showed that the migratory proton attached to Cα of the product also with retention of configuration. CcTAM is stereoselective for (R)-β-tyrosine (85%) yet also forms the (S)-β-tyrosine enantiomer (15%) through inversion of configuration at both migration termini, as described herein. The proportion of the (S)-β-isomer made by CcTAM during steady state interestingly increased with solvent pH, and this effect on the proposed reaction mechanism is also discussed.

  2. Modern control of mineral wool production process

    Directory of Open Access Journals (Sweden)

    Stankov Stanko P.

    2013-01-01

    Full Text Available In this paper, the control of the plant for mineral wool production consisting of a number of the technological units of different sizes and complexity is considered. The application of modern equipment based on PLC (Programmable Logic Controller and SCADA (Supervisory Control And Data Acquisition configuration provides optimal control of technological process. Described supervisory and control system is consisting of a number of units doing decentralized distributed control of technological entities where all possible situation are considered during work of machines and devices, which are installed in electric drive and are protected from technological and electrical accident. Transformer station and diesel engine, raw materials transport and dosage, processes in dome oven, centrifuges, polycondensation (PC chamber, burners, compressor station, binder preparation and dosage, wool cutting, completed panel packing and their transport to storehouse are controlled. Process variables and parameters like as level, flow, velocity, temperature, pressure, etc. are controlled. Control system is doing identification of process states changes, diagnostic and prediction of errors and provides prediction of behavior of control objects when input flows of materials and generates optimal values of control variables due to decreasing downtime and technic - economical requires connected to wool quality to be achieved. Supervisory and control system either eliminates unwanted changes in the production line or restricts them within the allowable limits according to the technology. In this way, the optimization of energy and raw materials consumption and appropriate products quality is achieved, where requirements are satisfied in accordance with process safety and environmental standards. SCADA provides a visual representation of controlled and uncontrolled parts of the technological process, processing alarms and events, monitoring of the changes of relevant

  3. Sequence variation determining stereochemistry of a Δ11 desaturase active in moth sex pheromone biosynthesis.

    Science.gov (United States)

    Ding, Bao-Jian; Carraher, Colm; Löfstedt, Christer

    2016-07-01

    A Δ11 desaturase from the oblique banded leaf roller moth Choristoneura rosaceana takes the saturated myristic acid and produces a mixture of (E)-11-tetradecenoate and (Z)-11-tetradecenoate with an excess of the Z isomer (35:65). A desaturase from the spotted fireworm moth Choristoneura parallela also operates on myristic acid substrate but produces almost pure (E)-11-tetradecenoate. The two desaturases share 92% amino acid identity and 97% amino acid similarity. There are 24 amino acids differing between these two desaturases. We constructed mutations at all of these positions to pinpoint the sites that determine the product stereochemistry. We demonstrated with a yeast functional assay that one amino acid at the cytosolic carboxyl terminus of the protein (258E) is critical for the Z activity of the C. rosaceana desaturase. Mutating the glutamic acid (E) into aspartic acid (D) transforms the C. rosaceana enzyme into a desaturase with C. parallela-like activity, whereas the reciprocal mutation of the C. parallela desaturase transformed it into an enzyme producing an intermediate 64:36 E/Z product ratio. We discuss the causal link between this amino acid change and the stereochemical properties of the desaturase and the role of desaturase mutations in pheromone evolution.

  4. Theoretical study on the mechanism and stereochemistry of the cinchona-thiourea organocatalytic hydrophosphonylation of an α-ketoester.

    Science.gov (United States)

    Li, Weiyi; Huang, Dongfeng; Lv, Yajing

    2013-11-21

    The mechanism and stereochemistry of the hydrophosphonylation of an α-ketoester with dimethylphosphonate (DMHP) catalyzed by a thiourea-cinchona organocatalyst have been studied by the ONIOM method. The calculations show that the catalytic cycle is a three-step process, including the deprotonation of DMHP, C-P bond formation via nucleophilic addition and proton transfer with the regeneration of the catalyst. The deprotonation of DMHP mediated by the basicity of the quinuclidine nitrogen atom is the rate-determining step for the entire reaction. The activation of the α-ketoester by the thiourea or protonated cinchona moiety of the bifunctional catalyst is comparatively investigated, and the former is energy-preferred. AIM combined with NBO analysis indicate that the multiple hydrogen bonds play essential roles in activating substrates, facilitating charge transfer and stabilizing transition states and intermediates. The stereochemistry of the reaction is controlled by the C-P bond formation step and originated from the chiral induction of the multiple hydrogen-bonding interactions. The bulkier substituent groups on the chiral scaffold of the catalyst may increase rigidity of the catalyst and the asymmetric induction to the substrates. The calculations predict that alkyl substituted α-ketoesters might also be converted to chiral α-hydroxyl phosphonates with high enantioselectivity.

  5. Effects of stereochemistry and copolymerization on the LCST of PNIPAm

    Science.gov (United States)

    de Oliveira, Tiago E.; Mukherji, Debashish; Kremer, Kurt; Netz, Paulo A.

    2017-01-01

    Poly(N-isopropylacrylamide) (PNIPAm) is a smart polymer that presents a lower critical transition temperature (LCST) of 305 K. Interestingly, this transition point falls within the range of the human body temperature, making PNIPAm a highly suitable candidate for bio-medical applications. However, it is sometimes desirable to have a rather flexible tuning of the LCST of these polymers to further increase their range of applications. In this work, we use all-atom molecular dynamics simulations to study the LCST of PNIPAm-based (co-)polymers. We study different molecular architectures where the polymer sequences are tuned either by modifying its stereochemistry or by the co-polymerization of PNIPAm with acrylamide (Am) units. Our analysis connects global polymer conformations with the microscopic intermolecular interactions. These findings suggest that the collapse of a PNIPAm chain upon heating is dependent on the hydration structure around the monomers, which is strongly dependent on the tacticity and the presence of more hydrophilic acrylamide monomers. Our results are found to be in good agreement with the existing experimental data.

  6. Accurate stereochemistry for two related 22,26-epiminocholestene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Vega-Baez, José Luis; Sandoval-Ramírez, Jesús; Meza-Reyes, Socorro; Montiel-Smith, Sara; Gómez-Calvario, Victor [Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, San Manuel, 72000 Puebla, Pue. (Mexico); Bernès, Sylvain, E-mail: sylvain-bernes@hotmail.com [DEP Facultad de Ciencias Químicas, UANL, Guerrero y Progreso S/N, Col. Treviño, 64570 Monterrey, NL (Mexico); Facultad de Ciencias Químicas, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, San Manuel, 72000 Puebla, Pue. (Mexico)

    2008-04-01

    Regioselective opening of ring E of solasodine under various conditions afforded (25R)-22,26-epimino@@cholesta-5,22(N)-di@@ene-3β,16β-diyl diacetate (previously known as 3,16-diacetyl pseudosolasodine B), C{sub 31}H{sub 47}NO{sub 4}, or (22S,25R)-16β-hydr@@oxy-22,26-epimino@@cholesta-5-en-3β-yl acetate (a derivative of the naturally occurring alkaloid oblonginine), C{sub 29}H{sub 47}NO{sub 3}. In both cases, the reactions are carried out with retention of chirality at the C16, C20 and C25 stereogenic centers, which are found to be S, S and R, respectively. Although pseudosolasodine was synthesized 50 years ago, these accurate assignments clarify some controversial points about the actual stereochemistry for these alkaloids. This is of particular importance in the case of oblonginine, since this compound is currently under consideration for the treatment of aphasia arising from apoplexy; the present study defines a diastereoisomerically pure compound for pharmacological studies.

  7. Correlation between the Stereochemistry and Bioactivity in Octahedral Rhodium Prolinato Complexes.

    Science.gov (United States)

    Rajaratnam, Rajathees; Martin, Elisabeth K; Dörr, Markus; Harms, Klaus; Casini, Angela; Meggers, Eric

    2015-08-17

    Controlling the relative and absolute configuration of octahedral metal complexes constitutes a key challenge that needs to be overcome in order to fully exploit the structural properties of octahedral metal complexes for applications in the fields of catalysis, materials sciences, and life sciences. Herein, we describe the application of a proline-based chiral tridentate ligand to decisively control the coordination mode of an octahedral rhodium(III) complex. We demonstrate the mirror-like relationship of synthesized enantiomers and differences between diastereomers. Further, we demonstrate, using the established pyridocarbazole pharmacophore ligand as part of the organometallic complexes, the importance of the relative and absolute stereochemistry at the metal toward chiral environments like protein kinases. Protein kinase profiling and inhibition data confirm that the proline-based enantiopure rhodium(III) complexes, despite having all of the same constitution, differ strongly in their selectivity properties despite their unmistakably mutual origin. Moreover, two exemplary compounds have been shown to induce different toxic effects in an ex vivo rat liver model.

  8. Management Control in New Product Development

    DEFF Research Database (Denmark)

    Jørgensen, Brian; Messner, Martin

    2009-01-01

    Several studies in management control have drawn upon the concepts of coercive and enabling forms of bureaucracy (Adler and Borys 1996) to discuss how the features of a control system may affect employees' attitudes toward control. This question is relevant because enabling forms of control allow...... organizations to better manage tensions between efficiency and flexibility, which is arguably a key issue in many organizations today. Our paper contributes to this stream of research by detailing how enabling control functions in the particular setting of new product development. To this end, we draw upon...... empirical material collected through an in-depth field study carried out in a manufacturing organization. We use data from interviews, participant observation, and internal documentation in this firm to demonstrate how the combination of different control mechanisms helps the organization balance efficiency...

  9. Decision Support for effective production control

    DEFF Research Database (Denmark)

    Africa, E.; Nehzati, T.; Strandhagen, J.O.;

    2012-01-01

    This study aims to identify the actual needs of decision makers for decision support in the production control activity, considering the role and cognitive skills of human decision-makers in the decision-making process. Multiple case studies have been conducted in order to gain practical insights...

  10. Internal transport control in pot plant production

    NARCIS (Netherlands)

    Annevelink, E.

    1999-01-01

    Drawing up internal transport schedules in pot plant production is a very complex task. Scheduling internal transport at the operational level and providing control on a day-to-day or even hour-to-hour basis in particular requires a new approach. A hierarchical planning approach based on

  11. A Projection of Automated Book Production Control

    Directory of Open Access Journals (Sweden)

    Mario Barisic

    2006-12-01

    Full Text Available The paper elaborates on the recommendation of systematic introducing of XML technologies as a standard and integral factor in publishing and graphic business activities and as a further improvement of the existing PostScript graphic production platform. Procedures are proposed for applying norm setting in respect to production processes through related connections organized databases under XML technology in a hierarchical way, as well as a book production norm setting system. The proposal for work processes automation in the domain of printing business control is elaborated under the CIP4-JDF automating system. Operation results are used as guidelines for setting the elements of automated business operations in the book production domain, with integrated elements of new technologies, compatible with global trends.

  12. Robust Planning and Control Using Intelligent Products

    Science.gov (United States)

    Meyer, Gerben G.; Wortmann, J. C. (Hans)

    The advances in production planning and control in the last decades have confirmed the centralized nature of the planning function. However, centralization has disadvantages when quick response to local production problems is required. Therefore, renewed interest in decentralized approaches emerges. This paper investigates the possibility to use intelligent products for decentralized handling of disturbances. Intelligent products are aware of their local context and they can negotiate with local manufacturing resources. Therefore, local solutions for problems can be suggested, virtually at the same time at which the problem occurs. The paper demonstrates the viability of this approach via a simulation study. For reasons of comparison, the TAC SCM environment is used. Moreover, robustness is taken as an additional measurement of performance. The results of the simulations are encouraging.

  13. Management Control in New Product Development

    DEFF Research Database (Denmark)

    Jørgensen, Brian; Messner, Martin

    2009-01-01

    organizations to better manage tensions between efficiency and flexibility, which is arguably a key issue in many organizations today. Our paper contributes to this stream of research by detailing how enabling control functions in the particular setting of new product development. To this end, we draw upon......Several studies in management control have drawn upon the concepts of coercive and enabling forms of bureaucracy (Adler and Borys 1996) to discuss how the features of a control system may affect employees' attitudes toward control. This question is relevant because enabling forms of control allow...... that these repair efforts are perceived as not wholly satisfactory, which suggests that, in the case of important strategic changes, repair may require more top-down management intervention....

  14. Mechanics of human voice production and control

    Science.gov (United States)

    Zhang, Zhaoyan

    2016-01-01

    As the primary means of communication, voice plays an important role in daily life. Voice also conveys personal information such as social status, personal traits, and the emotional state of the speaker. Mechanically, voice production involves complex fluid-structure interaction within the glottis and its control by laryngeal muscle activation. An important goal of voice research is to establish a causal theory linking voice physiology and biomechanics to how speakers use and control voice to communicate meaning and personal information. Establishing such a causal theory has important implications for clinical voice management, voice training, and many speech technology applications. This paper provides a review of voice physiology and biomechanics, the physics of vocal fold vibration and sound production, and laryngeal muscular control of the fundamental frequency of voice, vocal intensity, and voice quality. Current efforts to develop mechanical and computational models of voice production are also critically reviewed. Finally, issues and future challenges in developing a causal theory of voice production and perception are discussed. PMID:27794319

  15. Evaluating Ketoreductase Exchanges as a Means of Rationally Altering Polyketide Stereochemistry.

    Science.gov (United States)

    Annaval, Thibault; Paris, Cédric; Leadlay, Peter F; Jacob, Christophe; Weissman, Kira J

    2015-06-15

    Modular polyketide synthases (PKSs) are multidomain multienzymes responsible for the biosynthesis in bacteria of a wide range of polyketide secondary metabolites of clinical value. The stereochemistry of these molecules is an attractive target for genetic engineering in attempts to produce analogues exhibiting novel therapeutic properties. The exchange of ketoreductase (KR) domains in model PKSs has been shown in several cases to predictably alter the configuration of the β-hydroxy functionalities but not of the α-methyl groups. By systematic screening of a broad panel of KR domains, we have identified two donor KRs that afford modification of α-methyl group stereochemistry. To the best of our knowledge, this provides the first direct in vivo evidence of KR-catalyzed epimerization. However, none of the introduced KRs afforded simultaneous alteration of methyl and hydroxy configurations in high yield. Therefore, swapping of whole modules might be necessary to achieve such changes in stereochemistry.

  16. Revision of the stereochemistry of elisabethatriene, a putative biosynthetic intermediate of pseudopterosins.

    Science.gov (United States)

    Nasuda, Masayuki; Ohmori, Miho; Ohyama, Kiyoshi; Fujimoto, Yoshinori

    2012-01-01

    In the past, we have questioned the accuracy of the stereochemistry of elisabethatriene, a putative biosynthetic intermediate of pseudopterosins, in light of the configuration of elisabethatrienol isolated from Pseudopterogorgia elisabethae, which was represented as 1S,4R,9S,11S. We have reinvestigated the stereochemistry of elisabethatriene. Elisabethatriene with the reported 1S,4R,9R,11S configuration was synthesized starting from (-)-isopulegol in its enantiomeric form. The (1)H- and (13)C-NMR data of the synthesized compound differed from those reported for elisabethatriene. In addition to the fact that elisabethatriene is converted into pseudopterosins, this finding has allowed us to propose that elisabethatriene should have the 1S,4R,9S,11S stereochemistry, which is identical to that of elisabethatrienol.

  17. Controlling defectiveness in a complex product

    Energy Technology Data Exchange (ETDEWEB)

    Harris, C.L.

    1976-09-01

    A common practice when measuring defectiveness in a complicated product is to assign ''demerit'' points to each defect in proportion to the seriousness of the fault. A plan is presented for monitoring defectives by using a modified demerit per unit control chart. The statistics presented are basic to control charts for demerits. What is different is the chart format which has the advantage of minimum effort for daily updates and independence from required sample sizes. Basically, the charts were designed for simplicity of use where product quantities are not large. Emphasis is placed on maintaining perspective between plotting data and completing the circle of defect reporting, analysis and corrective action feedback.

  18. Operation and Control of Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Huusom, Jakob Kjøbsted; Nordblad, Mathias

    -product. Current literature indicates that enzymatic processing of oils and fats to produce biodiesel is technically feasible and developments in immobilization technology indicate that enzyme catalysts can become cost effective compared to chemical processing. However, with very few exceptions, enzyme technology...... is not currently used in commercial-scale biodiesel production. This is mainly due to non-optimized process designs, which do not use the full potential of the catalysts in a cost-efficient way. Furthermore is it unclear what process variables need to be monitored and controlled to ensure optimal economics...... an enzymatic route, batch operation is a straightforward and efficient means for producing BD with its main disadvantage being the downtime between batches. For large-scale production of biodiesel, continuous operation is an attractive alternative as it enables efficient use of manpower and capital assets...

  19. Decision Support for effective production control

    DEFF Research Database (Denmark)

    Africa, E.; Nehzati, T.; Strandhagen, J.O.

    2012-01-01

    This study aims to identify the actual needs of decision makers for decision support in the production control activity, considering the role and cognitive skills of human decision-makers in the decision-making process. Multiple case studies have been conducted in order to gain practical insights...... from the manufacturing industry. This paper contributes to raise the issues that should be considered for successful implementation of the decision support systems in practice....

  20. Determination of absolute stereochemistry, total synthesis, and evaluation of peptides from the myxomycete Physarum melleum.

    Science.gov (United States)

    Hanazawa, Shuwa; Arai, Midori A; Li, Xiaofan; Ishibashi, Masami

    2008-01-01

    The absolute stereochemistry of melleumin A (1) and B (2), novel peptide compounds isolated from the myxomycete Physarum melleum, was determined by synthesis of their segments and by a modified Mosher's method. Total synthesis of melleumin B (2) was achieved by a stereoselective method, which provided further evidence for all the absolute stereochemistries of melleumin B (2). The Wnt signal inhibitory activities of 2 and its 10R-epimer 19 were evaluated. Compound 19 showed moderate inhibition of Wnt signal transcription, which suggests that melleumin analogues might be useful as Wnt signal inhibitors.

  1. Host-Guest Assembly of a Molecular Reporter with Chiral Cyanohydrins for Assignment of Absolute Stereochemistry.

    Science.gov (United States)

    Gholami, Hadi; Anyika, Mercy; Zhang, Jun; Vasileiou, Chrysoula; Borhan, Babak

    2016-06-27

    The absolute stereochemistry of cyanohydrins, derived from ketones and aldehydes, is obtained routinely, in a microscale and derivatization-free manner, upon their complexation with Zn-MAPOL, a zincated porphyrin host with a binding pocket comprised of a biphenol core. The host-guest complex leads to observable exciton-coupled circular dichroism (ECCD), the sign of which is easily correlated to the absolute stereochemistry of the bound cyanohydrin. A working model, based on the ECCD signal of cyanohydrins with known configuration, is proposed.

  2. 21 CFR 226.40 - Production and control procedures.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Production and control procedures. 226.40 Section...) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR TYPE A MEDICATED ARTICLES Product Quality Control § 226.40 Production and control procedures. Production and control procedures shall include...

  3. 21 CFR 820.70 - Production and process controls.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Production and process controls. 820.70 Section...) MEDICAL DEVICES QUALITY SYSTEM REGULATION Production and Process Controls § 820.70 Production and process controls. (a) General. Each manufacturer shall develop, conduct, control, and monitor production...

  4. 21 CFR 211.188 - Batch production and control records.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Batch production and control records. 211.188... Reports § 211.188 Batch production and control records. Batch production and control records shall be... production and control of each batch. These records shall include: (a) An accurate reproduction of...

  5. Production planning and control of less emitting production systems

    Energy Technology Data Exchange (ETDEWEB)

    Haasis, H.D. [Bremen Univ. (Germany)

    1995-12-31

    The concept of integral environmental protection has been growing in importance within Western Europe in recent years. Increasingly, it has come to be recognized that no one part of the environment is separate from any other, it functions as a whole. Yet, pollution control was until recently, usually based on an approach which considers emissions to air, water, and land separately. That has begun to change, particularly since the 1987 report by the World Commission on Environment and Development. This can be recognized, for example, within the proposal for a Directive of the Council of the European Union on Integrated Pollution Prevention and Control. By this, the environmental media are placed on an equal legislative footing so that the final result will be that the way in which an installation is operated will be better for the whole environment. In other words, less emission production systems are obtained. Realization of an integral concept or of less emission production systems initially requires technical measures for the avoidance and the minimization of emissions, as well as recovery and recycling of materials and substances

  6. QUALITY CONTROL OF SOME TRADITIONAL MEAT PRODUCTS

    Directory of Open Access Journals (Sweden)

    S. DOBRINAS

    2014-03-01

    Full Text Available In this paper, we present the characterization of six traditional meat products: smoked file, smoked bacon, pork sausages, sausage prepared from swine’s entrails, pork pastrami, sheep sausages. Organoleptic tests (the aspect and shape, the aspect of freshly cut in the section, smell, taste and consistency, physico-chemical and microbiological determinations (NTG, Salmonella, Listeria monocytogenes and Escherichia coli were performed. These analyzes are a part of quality control that must be done in order to obtain a certificate from the Ministry of Agriculture for a traditional product. After identification of H2S and starch and according to fat oxidation degree it was concluded that analyzed samples didn’t contain counterfeiters and all parameters analyzed are within the maximum limits allowed by law. Considering all the procedures for manufacturing, characteristics of raw and auxiliary materials, organoleptic properties of final products analyzed in this study, it can be concluded that analyzed meat specialties meet the requirements of Ministry Order no. 690/28.09.2004 for the traditional products certification.

  7. Stereochemistry and Mechanistic Insight in the [2(k)+2(i)+2(i)] Annulations of Ketenes and Imines.

    Science.gov (United States)

    Yang, Zhanhui; He, Wei; Cheng, Baoxiang; Xu, Jiaxi

    2016-06-03

    The stereochemistry and mechanistic insight in the annulations of one ketene molecule with two imine molecules ([2(k)+2(i)+2(i)] annulation) are studied by using six-membered 3,4-dihydroisoquinoline as an imine probe. A concerted hetero-Diels-Alder cycloaddition mechanism is proposed to explain the stereochemical outcomes. In most cases, the zwitterionic 2-aza-1,3-butadiene-type intermediates, generated from ketenes and imines, undergo endo hetero-Diels-Alder cycloaddition with the second imine molecule. For ketenes with electron-donating substituents, (2,4)-cis-(4,5)-cis-[2(k)+2(i)+2(i)] annuladducts formed stereospecifically, while, for ketenes with electron-accepting substituents, (2,4)-cis-(4,5)-trans-[2(k)+2(i)+2(i)] annuladducts are generated stereospecifically. The [2(k)+2(i)+2(i)] annulations of aryloxyketenes and 3,4-dihydroisoquinoline give stereodivergent products due to the occurrence of the stepwise nucleophilic annulation. However, in the [2(k)+2(i)+2(i)] annulations of seven-membered cyclic imine dibenzo[b,f][1,4]oxazepine, the zwitterionic aza-butadiene-type intermediates exclusively undergo exo hetero-Diels-Alder cycloadditions with another molecule of imine to yield (2,4)-trans-(4,5)-trans-[2(k)+2(i)+2(i)] annuladducts stereospecifically, regardless of the ketene substituents. The mechanistic model not only discloses the nature of the [2(k)+2(i)+2(i)] annulations, but also can be used to explain and predict the stereochemistry of the [2(k)+2(i)+2(i)] annuladducts from different ketenes and imines.

  8. 21 CFR 211.186 - Master production and control records.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Master production and control records. 211.186... Reports § 211.186 Master production and control records. (a) To assure uniformity from batch to batch, master production and control records for each drug product, including each batch size thereof, shall...

  9. Using NMR to Probe the Regio- and Stereochemistry of the Hydration of 1-Hexene

    Science.gov (United States)

    Saba, Shahrokh; Clarke, Donald D.; Iwanoski, Christa; Lobasso, Thomas

    2010-01-01

    This undergraduate organic laboratory experiment complements previously described and popular experiments on hydration of 1-hexene where students experimentally establish the Markovnikov regioselectivity of alkene hydration. In this experiment, students explore not only the regiochemistry but also the stereochemistry of 1-hexene hydration and…

  10. A Wet-Lab Approach to Stereochemistry Using [superscript 31]P NMR Spectroscopy

    Science.gov (United States)

    Fenton, Owen S.; Sculimbrene, Bianca R.

    2011-01-01

    Understanding stereochemistry is an important and difficult task for students to master in organic chemistry. In both introductory and advanced courses, students are encouraged to explore the spatial relationships between molecules, but this exploration is often limited either to the lecture hall or the confines of the library. As such, we sought…

  11. Implementation and Student Testing of a Web-Based, Student-Centered Stereochemistry Tutorial

    Science.gov (United States)

    Burrmann, Nicola J.; Moore, John W.

    2015-01-01

    The implementation of a web-based stereochemistry tutorial, which allows students to select their preferred structural representation and method for making stereochemical comparisons between molecules, is discussed. The tutorial was evaluated by students in three different introductory organic chemistry courses at a large midwestern university.…

  12. Oil Reservoir Production Optimization using Optimal Control

    DEFF Research Database (Denmark)

    Völcker, Carsten; Jørgensen, John Bagterp; Stenby, Erling Halfdan

    2011-01-01

    Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using the adjo......Practical oil reservoir management involves solution of large-scale constrained optimal control problems. In this paper we present a numerical method for solution of large-scale constrained optimal control problems. The method is a single-shooting method that computes the gradients using...... the adjoint method. We use an Explicit Singly Diagonally Implicit Runge-Kutta (ESDIRK) method for the integration and a quasi-Newton Sequential Quadratic Programming (SQP) algorithm for the constrained optimization. We use this algorithm in a numerical case study to optimize the production of oil from an oil...... reservoir using water ooding and smart well technology. Compared to the uncontrolled case, the optimal operation increases the Net Present Value of the oil field by 10%....

  13. Stereochemistry of 1,2-elimination and proton-transfer reactions: toward a unified understanding.

    Science.gov (United States)

    Mohrig, Jerry R

    2013-07-16

    Many mechanistic and stereochemical studies have focused on the breaking of the C-H bond through base-catalyzed elimination reactions. When we began our research, however, chemists knew almost nothing about the stereospecificity of addition-elimination reactions involving conjugated acyclic carbonyl compounds, even though the carbonyl group is a pivotal functional group in organic chemistry. Over the last 25 years, we have studied the addition-elimination reactions of β-substituted acyclic esters, thioesters, and ketones in order to reach a comprehensive understanding of how electronic effects influence their stereochemistry. This Account brings together our understanding of the stereochemistry of 1,2-elimination and proton-transfer reactions, describing how each study has built upon previous work and contributed to our understanding of this field. When we began, chemists thought that anti stereospecificity in base-catalyzed 1,2-elimination reactions occurred via concerted E2 mechanisms, which provide a smooth path for anti elimination. Unexpectedly, we discovered that some E1cBirrev reactions produce the same anti stereospecificity as E2 reactions even though they proceed through diffusionally equilibrated, "free" enolate-anion intermediates. This result calls into question the conventional wisdom that anti stereochemistry must result from a concerted mechanism. While carrying out our research, we developed insights ranging from the role of historical contingency in the evolution of hydratase-dehydratase enzymes to the influence of buffers on the stereochemistry of H/D exchange in D2O. Negative hyperconjugation is the most important concept for understanding our results. This idea provides a unifying view for the largely anti stereochemistry in E1cBirrev elimination reactions and a basis for understanding the stereoelectronic influence of electron-withdrawing β-substituents on proton-transfer reactions.

  14. Microbial control of hydrogen sulfide production

    Energy Technology Data Exchange (ETDEWEB)

    Montgomery, A.D.; Bhupathiraju, V.K.; Wofford, N.; McInerney, M.J. [Univ. of Oklahoma, Tulsa, OK (United States)] [and others

    1995-12-31

    A sulfide-resistant strain of Thiobacillus denitrificans, strain F, prevented the accumulation of sulfide by Desulfovibrio desulfuricans when both organisms were grown in liquid medium. The wild-type strain of T. denitrificans did not prevent the accumulation of sulfide produced by D. desulfuricans. Strain F also prevented the accumulation of sulfide by a mixed population of sulfate-reducing bacteria enriched from an oil field brine. Fermentation balances showed that strain F stoichiometrically oxidized the sulfide produced by D. desulfuricans and the oil field brine enrichment to sulfate. The ability of a strain F to control sulfide production in an experimental system of cores and formation water from the Redfield, Iowa, natural gas storage facility was also investigated. A stable, sulfide-producing biofilm was established in two separate core systems, one of which was inoculated with strain F while the other core system (control) was treated in an identical manner, but was not inoculated with strain F. When formation water with 10 mM acetate and 5 mM nitrate was injected into both core systems, the effluent sulfide concentrations in the control core system ranged from 200 to 460 {mu}M. In the test core system inoculated with strain F, the effluent sulfide concentrations were lower, ranging from 70 to 110 {mu}M. In order to determine whether strain F could control sulfide production under optimal conditions for sulfate-reducing bacteria, the electron donor was changed to lactate and inorganic nutrients (nitrogen and phosphate sources) were added to the formation water. When nutrient-supplemented formation water with 3.1 mM lactate and 10 mM nitrate was used, the effluent sulfide concentrations of the control core system initially increased to about 3,800 {mu}M, and then decreased to about 1,100 {mu}M after 5 weeks. However, in the test core system inoculated with strain F, the effluent sulfide concentrations were much lower, 160 to 330 {mu}M.

  15. Synthesis, stereochemistry determination, pharmacological studies and quantum chemical analyses of bisthiazolidinone derivative

    Science.gov (United States)

    Mushtaque, Md.; Avecilla, Fernando; Hafeez, Zubair Bin; Jahan, Meriyam; Khan, Md. Shahzad; Rizvi, M. Moshahid A.; Khan, Mohd. Shahid; Srivastava, Anurag; Mallik, Anwesha; Verma, Saurabh

    2017-01-01

    A new compound (3) bisthaizolidinone derivative was synthesized by Knoevenagel condensation reaction. The structure of synthesized compound was elucidated by different spectral techniques and X-ray diffraction studies. The stereochemistry of the compound (3) was determined by 1Hsbnd 1H NOESY, 1Hsbnd 1H NMR COSY and single crystal X-ray diffraction studies as (Z, Z)-configuration. The computational quantum chemical studies of compound(3) like, IR, UV, NBO analysis were performed by DFT with Becke-3-Lee-Yang-Parr (B3LYP) exchange-correlation functional in combination with 6-311++G(d,p) basis sets. The DNA-binding of compound (3) exhibited a moderate binding constant (Kb = 1 × 105 Lmol-1) with hypochromic shift. The molecular docking displayed good binding affinity -7.18 kcal/mol. The MTT assay of compound (3) was screened against different cancerous cell lines, HepG2, Siha, Hela and MCF-7. Studies against these cell lines depicted that the screened compound (3) showed potent inhibitory activity against HepG2 cell (IC50 = 7.5 μM) followed by MCF-7 (IC50 = 52.0 μM), Siha (IC50 = 66.98 μM), Hela (IC50 = 74.83 μM) cell lines, and non-toxic effect against non-cancerous HEK-293 cells (IC50 = 287.89 μM) at the concentration range (0-300) μM. Furthermore, cell cycle perturbation was performed on HepG2 & Siha cell lines and observed that cells were arrested in G2/M in HepG2, and G0/G1 in Siha cell lines with respect to untreated control. Hence, compound (3) possesses potent anti-cancerous activity against HepG2 cell line.

  16. Wind farms production: Control and prediction

    Science.gov (United States)

    El-Fouly, Tarek Hussein Mostafa

    Wind energy resources, unlike dispatchable central station generation, produce power dependable on external irregular source and that is the incident wind speed which does not always blow when electricity is needed. This results in the variability, unpredictability, and uncertainty of wind resources. Therefore, the integration of wind facilities to utility electrical grid presents a major challenge to power system operator. Such integration has significant impact on the optimum power flow, transmission congestion, power quality issues, system stability, load dispatch, and economic analysis. Due to the irregular nature of wind power production, accurate prediction represents the major challenge to power system operators. Therefore, in this thesis two novel models are proposed for wind speed and wind power prediction. One proposed model is dedicated to short-term prediction (one-hour ahead) and the other involves medium term prediction (one-day ahead). The accuracy of the proposed models is revealed by comparing their results with the corresponding values of a reference prediction model referred to as the persistent model. Utility grid operation is not only impacted by the uncertainty of the future production of wind farms, but also by the variability of their current production and how the active and reactive power exchange with the grid is controlled. To address this particular task, a control technique for wind turbines, driven by doubly-fed induction generators (DFIGs), is developed to regulate the terminal voltage by equally sharing the generated/absorbed reactive power between the rotor-side and the gridside converters. To highlight the impact of the new developed technique in reducing the power loss in the generator set, an economic analysis is carried out. Moreover, a new aggregated model for wind farms is proposed that accounts for the irregularity of the incident wind distribution throughout the farm layout. Specifically, this model includes the wake effect

  17. DWPF waste glass Product Composition Control System

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.G.; Postles, R.L.

    1992-07-01

    The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canisters for cooling and, ultimately, shipment to and storage in a geologic repository. The Product Composition Control System (PCCS) is the system intended to ensure that the melt will be processible and that the glass wasteform will be acceptable. This document provides a description of this system.

  18. DWPF waste glass Product Composition Control System

    Energy Technology Data Exchange (ETDEWEB)

    Brown, K.G.; Postles, R.L.

    1992-01-01

    The Defense Waste Processing Facility (DWPF) will be used to blend aqueous radwaste (PHA) with solid radwaste (Sludge) in a waste receipt vessel (the SRAT). The resulting SRAT material is transferred to the SME an there blended with ground glass (Frit) to produce a batch of melter feed slurry. The SME material is passed to a hold tank (the MFT) which is used to continuously feed the DWPF melter. The melter. The melter produces a molten glass wasteform which is poured into stainless steel canisters for cooling and, ultimately, shipment to and storage in a geologic repository. The Product Composition Control System (PCCS) is the system intended to ensure that the melt will be processible and that the glass wasteform will be acceptable. This document provides a description of this system.

  19. Stereochemistry of Pd(II)-Catalyzed THF Ring Formation of ε-Hydroxy Allylic Alcohols and Synthesis of 2,3,5-Trisubstituted and 2,3,4,5-Tetrasubstituted Tetrahydrofurans.

    Science.gov (United States)

    Murata, Yuki; Uenishi, Jun'ichi

    2016-09-02

    Pd(II)-catalyzed ring formation of 2,3,5-trisubstituted and 2,3,4,5-tetrasubstituted tetrahydrofurans is described. Oxypalladation of a chiral ε-hydroxy allylic alcohol provides a 5-alkenyltetrahydrofuran ring in excellent yields via a 5-exo-trigonal process. Nine substrates including six secondary allylic alcohols and three primary allylic alcohols with or without an additional secondary hydroxy substituent at the γ-position have been examined. Their structures are restricted by a 2,2,4,4-tetraisopropyl-1,3,5,2,4-trioxadisilocane ring. The stereochemistry of the resulting tetrahydrofuran products was determined by chemical transformation. The reaction mechanism is discussed on the basis of the stereochemical results. The steps in the chiral allylic alcohol directed or the nucleophilic alcohol directed facial selection for the formation of the alkene-Pd(II)-π-complex, the cis-oxypalladation, and a syn-elimination mechanism account for the observed stereochemistry of the reaction.

  20. 46 CFR 164.019-13 - Production quality control requirements.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Production quality control requirements. 164.019-13....019-13 Production quality control requirements. (a) General. Each component manufacturer shall establish procedures for maintaining quality control of the materials used in production,...

  1. Correction: Absolute stereochemistry and preferred conformations of urate degradation intermediates from computed and experimental circular dichroism spectra.

    Science.gov (United States)

    Pipolo, Silvio; Percudani, Riccardo; Cammi, Roberto

    2016-04-14

    Correction for 'Absolute stereochemistry and preferred conformations of urate degradation intermediates from computed and experimental circular dichroism spectra' by Silvio Pipolo et al., Org. Biomol. Chem., 2011, 9, 5149-5155.

  2. Stereochemistry of the tadalafil diastereoisomers: a critical assessment of vibrational circular dichroism, electronic circular dichroism, and optical rotatory dispersion.

    Science.gov (United States)

    Qiu, Shi; De Gussem, Ewoud; Tehrani, Kourosch Abbaspour; Sergeyev, Sergey; Bultinck, Patrick; Herrebout, Wouter

    2013-11-14

    The stereochemistry of all four stereoisomers of tadalafil is determined using vibrational circular dichroism (VCD), electronic circular dichroism (ECD), and optical rotatory dispersion (ORD) spectroscopy. By comparing experimentally obtained VCD spectra to computationally simulated ones, the absolute configuration of the enantiomeric pair (6R, 12aR)/(6S, 12aS) can be confidently assigned without prior knowledge of their relative stereochemistry. IR and NMR spectra are used to aid the assignment of the relative stereochemistry. The IR and VCD difference spectra further confirm the assignment of all stereoisomers. ECD and ORD spectra are used to investigate the complementarity of the three chiroptical techniques. VCD spectroscopy itself is found to have the ability to identify diastereoisomers, and simultaneous use of these chiroptical spectroscopic methods and NMR chemical shifts aids in increasing the reliability of stereochemistry assignment of diastereoisomers.

  3. Association between product quality control and process quality control of bulk milk

    NARCIS (Netherlands)

    Velthuis, A.; Asseldonk, van M.A.P.M.

    2010-01-01

    Assessment of dairy-milk quality is based on product quality control (testing bulk-milk samples) and process quality control (auditing dairy farms). It is unknown whether process control improves product quality. To quantify possible association between product control and process control a statisti

  4. Advanced monitoring and control in biopharmaceutical production

    NARCIS (Netherlands)

    Soons, Z.I.T.A.

    2008-01-01

    Bioprocesses are characterised by natural variability in raw materials, initial conditions, human intervention, and varying properties of the micro-organism. In traditional biopharmaceutical production quality of the product is currently tested at the end of the production process only. Recently the

  5. Production paths – an innovative concept for heavy machinery production planning and control

    OpenAIRE

    R. Lenort; R. Klepek; A. Samolejová; Besta, P.

    2013-01-01

    The paper introduces a new concept for planning and control of complicated heavy machinery production which is based on the principle of „production paths“ – production paths planning and control concept. The concept refl ects the limited applicability of traditional concepts and systems for production planning and control in conditions of heavy machinery industry that is specifi c by the limited repeatability of product structures and volumes, by complicated and variant material ...

  6. Synthesis and dynamic stereochemistry of 4-aryl-thiomorpholine-3,5-dione derivatives

    Science.gov (United States)

    Szawkało, Joanna; Maurin, Jan K.; Pluciński, Franciszek; Czarnocki, Zbigniew

    2015-01-01

    A series of new N-aryl-substituted thiomorpholine-3,5-diones were synthesized. Crystal structures of seven compounds were established on the basis of X-ray crystallography. Stable at room temperature diastereomers were detected for (2-phenyl)-substituted derivatives using 1H NMR. The dynamic stereochemistry of compound 36 was studied with variable-temperature 1H NMR and the mechanism of diastereomers interconversion was proposed on the basis of quantum chemical calculations.

  7. Relative Stereochemistry and Absolute Configuration of Farinosin, a Eudesmanolide From Encelia farinosa.

    Science.gov (United States)

    Ortega, Alfredo R; Sánchez-Castellanos, Mariano; Pérez-Hernández, Nury; Robles-Zepeda, Ramón E; Joseph-Nathan, Pedro; Quijano, Leovigildo

    2016-05-01

    The naturally occurring eudesmanolide farinosin () is now fully characterized for the first time despite its original isolation almost half a century ago. The early assumed relative stereochemistry and absolute configuration were confirmed by vibrational circular dichroism together with evaluation of the Hooft X-ray parameters. The molecular conformation is very similar in the gas stage and in the solid state. Chirality 28:415-419, 2016. © 2016 Wiley Periodicals, Inc.

  8. Stereochemistry of coordination compounds. From alfred werner to the 21st century.

    Science.gov (United States)

    von Zelewsky, Alex

    2014-01-01

    As a contribution to the scientific symposium, November 22nd, 2013, commemorating the Nobel Prize awarded to Alfred Werner in 1913, a presentation of the development of stereochemistry of coordination compounds during the past 120 years was given. Stereochemistry was fundamental to Werner's theory of coordination compounds. After Werner's death in 1919, stereochemistry in this field did not progress much further for almost 20 years, but then developed continuously. It was realized that stereochemical features of elements showing coordination numbers larger than four are responsible for an almost unlimited number of stereochemical possibilities, thus opening a molecular world of new structures. In the beginning of the 21st century, interest in the field rose again considerably, mainly due to the potential of stereoselective catalysis, and the self-assembly of supramolecular structures. An end of these developments is not in sight. Here an abbreviated version of the lecture is given. A PowerPoint(®) file, or a video of the presentation, can be downloaded.

  9. Biological control and sustainable food production

    NARCIS (Netherlands)

    Bale, J.S.; Lenteren, van J.C.; Bigler, F.

    2008-01-01

    The use of biological control for the management of pest insects pre-dates the modern pesticide era. The first major successes in biological control occurred with exotic pests controlled by natural enemy species collected from the country or area of origin of the pest (classical control). Augmentati

  10. Natural products and body weight control

    Directory of Open Access Journals (Sweden)

    Jay Lee

    2011-01-01

    Full Text Available The purpose of the review was to summarise the effect of some commonly available natural products used for body weight management. We collected data from PubMed and scientific journals. There are numerous publications on this topic, however we have summarized the most commonly available and potent natural products from recent 53 publications. The natural products analyzed in this paper include catechins, capsaicin, conjugated linoleic acid, fucoxanthin, soy isoflavone, glabridin, astaxanthin and cyaniding-3-glucoside. These natural products are effective and safe for body weight management. Further studies need to be conducted to investigate the mechanism of action, metabolism, long term safety and side effects of these natural products, as well as interactions between these natural products with dietary components.

  11. Underlying Factors for Practicality of the Production Control Systems

    DEFF Research Database (Denmark)

    Arica, Emrah; Strandhagen, Jan Ola; Hvolby, Hans-Henrik

    2012-01-01

    This paper gives indications to important factors that must be considered for effectiveness of the production control systems under uncertainty. Five key factors have been identified by the literature study. Production schedule generation and execution approach under uncertainty, information...

  12. Stereochemical Control in the Still-Wittig Rearrangement Synthesis of Cyclohexyl (Z-Alkene Inhibitors of Pin1.

    Directory of Open Access Journals (Sweden)

    Xingguo R Chen

    Full Text Available Three stereoisomeric inhibitors of Pin1: (2R,5S-, (2S,5R- and (2S,5S-Ac-pSer-Ψ[(ZCH = C]-pipecolyl(Pip-2-(2-naphthylethylamine 1, that mimic L-pSer-D-Pro, D-pSer-L-Pro, and D-pSer-D-Pro amides respectively, were synthesized by a 13-step route. The newly formed stereogenic centers in the pipecolyl ring were introduced by Luche reduction, followed by stereospecific [2,3]-Still-Wittig rearrangement. The (Z- to (E-alkene ratio in the rearrangements were consistently 5.5 to 1. The stereochemistry at the original Ser α-carbon controlled the stereochemistry of the Luche reduction, but it did not affect the stereochemical outcome of the rearrangement, which consistently gave the (Z-alkene. The epimerized by-product, (2S,5S-10, resulting from the work-up after Na/NH3 debenzylation of (2S,5R-9, was carried on to the (2S,5S-1 isomer. Compound (2S,5S-10 was resynthesized from the Luche reduction by-product, (2R,3R-3, and the stereochemistry was confirmed by comparison of the optical rotations. The IC50 values for (2R,5S-1, (2S,5R-1 and (2S,5S-1 Pin1 inhibition were: 52, 85, and 140 μM, respectively.

  13. Direct product quality control for energy efficient climate controlled transport of agro-material

    NARCIS (Netherlands)

    Verdijck, G.J.C.; Preisig, H.A.; Straten, van G.

    2005-01-01

    A (model-based) Product Quality Controller is presented for climate controlled operations involving agro-material, such as storage and transport. This controller belongs to the class of Model Predictive Controllers and fits in a previously developed hierarchical control structure. The new Product

  14. Speech production as state feedback control.

    Science.gov (United States)

    Houde, John F; Nagarajan, Srikantan S

    2011-01-01

    Spoken language exists because of a remarkable neural process. Inside a speaker's brain, an intended message gives rise to neural signals activating the muscles of the vocal tract. The process is remarkable because these muscles are activated in just the right way that the vocal tract produces sounds a listener understands as the intended message. What is the best approach to understanding the neural substrate of this crucial motor control process? One of the key recent modeling developments in neuroscience has been the use of state feedback control (SFC) theory to explain the role of the CNS in motor control. SFC postulates that the CNS controls motor output by (1) estimating the current dynamic state of the thing (e.g., arm) being controlled, and (2) generating controls based on this estimated state. SFC has successfully predicted a great range of non-speech motor phenomena, but as yet has not received attention in the speech motor control community. Here, we review some of the key characteristics of speech motor control and what they say about the role of the CNS in the process. We then discuss prior efforts to model the role of CNS in speech motor control, and argue that these models have inherent limitations - limitations that are overcome by an SFC model of speech motor control which we describe. We conclude by discussing a plausible neural substrate of our model.

  15. Speech production as state feedback control

    Directory of Open Access Journals (Sweden)

    John F Houde

    2011-10-01

    Full Text Available Spoken language exists because of a remarkable neural process. Inside a speaker’s brain, an intended message gives rise to neural signals activating the muscles of the vocal tract. The process is remarkable because these muscles are activated in just the right way that the vocal tract produces sounds a listener understands as the intended message. What is the best approach to understanding the neural substrate of this crucial motor control process? One of the key recent modeling developments in neuroscience has been the use of state feedback control (SFC theory to explain the role of the CNS in motor control. SFC postulates that the CNS controls motor output by (1 estimating the current dynamic state of the thing (e.g., arm being controlled, and (2 generating controls based on this estimated state. SFC has successfully predicted a great range of non-speech motor phenomena, but as yet has not received attention in the speech motor control community. Here, we review some of the key characteristics of speech motor control and what they say about the role of the CNS in the process. We then discuss prior efforts to model the role of CNS in speech motor control, and argue that these models have inherent limitations – limitations that are overcome by an SFC model of speech motor control which we describe. We conclude by discussing a plausible neural substrate of our model.

  16. Production Quality Control Of Microfluidic Chip Designs

    DEFF Research Database (Denmark)

    Calaon, Matteo; Hansen, Hans Nørgaard; Tosello, Guido

    2012-01-01

    process chain, test geometries were designed and produced on the side of the functional features. The so called “Finger Print” of the lithography and molding processes was qualitatively and quantitatively evaluated through scanning electron microscopy and atomic force microscopy respectively. The entire......The challenge of fabricating geometries with critical dimensions ranging from few microns down to 10 nanometers with high production rate is delaying the development of nanotechnology based products. Diverse research works have shown the capability of technologies such as UV lithography, nano...... imprint lithography and e-beam lithography to produce micro and nano features. However, their application for tooling purposes is relatively new and the potential to produce nanometer features with high volume low cost production is enormous. Considering possible implementation in a mass production...

  17. Regioselectivity and stereochemistry of the synthesized sulfated polysaccharides

    OpenAIRE

    前田, 昌徹

    1998-01-01

    A novel sulfated β-1,3-xylan product was synthesized from algal cell wall microfibril homoxylan by the N,N-dimethylformamide (DMF)-SO3 complex sulfation method. Antithrombin activity appeared in this product was 6.5 times higher than that of standard heparin. From the results of 1H- and 13C-NMR spectroscopic analysis by DQF-COSY and HMQC, it was revealed that the ordered structure of β-1,3-xylan as a triple helix decayed and the resulting conformational change had been caused by the sulfatio...

  18. Structure and stereochemistry of the base excision repair glycosylase MutY reveal a mechanism similar to retaining glycosidases.

    Science.gov (United States)

    Woods, Ryan D; O'Shea, Valerie L; Chu, Aurea; Cao, Sheng; Richards, Jody L; Horvath, Martin P; David, Sheila S

    2016-01-29

    MutY adenine glycosylases prevent DNA mutations by excising adenine from promutagenic 8-oxo-7,8-dihydroguanine (OG):A mismatches. Here, we describe structural features of the MutY active site bound to an azaribose transition state analog which indicate a catalytic role for Tyr126 and approach of the water nucleophile on the same side as the departing adenine base. The idea that Tyr126 participates in catalysis, recently predicted by modeling calculations, is strongly supported by mutagenesis and by seeing close contact between the hydroxyl group of this residue and the azaribose moiety of the transition state analog. NMR analysis of MutY methanolysis products corroborates a mechanism for adenine removal with retention of stereochemistry. Based on these results, we propose a revised mechanism for MutY that involves two nucleophilic displacement steps akin to the mechanisms accepted for 'retaining' O-glycosidases. This new-for-MutY yet familiar mechanism may also be operative in related base excision repair glycosylases and provides a critical framework for analysis of human MutY (MUTYH) variants associated with inherited colorectal cancer.

  19. Stereochemistry of spiro-acetalized [60]fullerenes: how the exo and endo stereoisomers influence organic solar cell performance.

    Science.gov (United States)

    Mikie, Tsubasa; Saeki, Akinori; Yamazaki, Yu; Ikuma, Naohiko; Kokubo, Ken; Seki, Shu

    2015-04-29

    Exploiting bis-addition products of fullerenes is a rational way to improve the efficiency of bulk heterojunction-type organic photovoltaic cells (OPV); however, this design inherently produces regio- and stereoisomers that may impair the ultimate performance and fabrication reproducibility. Here, we report unprecedented exo and endo stereoisomers of the spiro-acetalized [60]fullerene monoadduct with methyl- or phenyl-substituted 1,3-dioxane (SAF6). Although there is no chiral carbon in either the reagent or the fullerene, equatorial (eq) rather than axial (ax) isomers are selectively produced at an exo-eq:endo-eq ratio of approximately 1:1 and can be easily separated using silica gel column chromatography. Nuclear Overhauser effect measurements identified the conformations of the straight exo isomer and bent endo isomer. We discuss the origin of stereoselectivity, the anomeric effect, intermolecular ordering in the film state, and the performance of poly(3-hexylthiophene):substituted SAF6 OPV devices. Despite their identical optical and electrochemical properties, their solubilities and space-charge limited current mobilities are largely influenced by the stereoisomers, which leads to variation in the OPV efficiency. This study emphasizes the importance of fullerene stereochemistry for understanding the relationship between stereochemical structures and device output.

  20. Association between product quality control and process quality control of bulk milk

    OpenAIRE

    Velthuis, A.; Asseldonk, van, M.M.L.

    2010-01-01

    Assessment of dairy-milk quality is based on product quality control (testing bulk-milk samples) and process quality control (auditing dairy farms). It is unknown whether process control improves product quality. To quantify possible association between product control and process control a statistical analysis was conducted. The analysis comprised 64.373 audit results on 26,953 dairy farms and all conducted lab tests of bulk-milk samples two, six or 12 months before the audit. Lab results in...

  1. Planetary camera control improves microfiche production

    Science.gov (United States)

    Chesterton, W. L.; Lewis, E. B.

    1965-01-01

    Microfiche is prepared using an automatic control system for a planetary camera. The system provides blank end-of-row exposures and signals card completion so the legend of the next card may by photographed.

  2. Developing an Integrated Set of Production Planning and Control Models

    OpenAIRE

    Wang, Hui

    2012-01-01

    This paper proposes an integrated set of production planning and control models that can be applied in the Push system (Make-to-stock). The integrated model include forecasting, aggregate planning, materials requirements planning, inventory control, capacity planning and scheduling. This integrated model solves the planning issues via three levels, which include strategic level, tactical level and operational level. The model obtains the optimal production plan for each product type in each p...

  3. Systematic Product Development of Control and Diagnosis Functionalities

    Science.gov (United States)

    Stetter, R.; Simundsson, A.

    2017-01-01

    In the scientific field of systematic product development a wide range of helpful methods, guidelines and tools were generated and published in recent years. Until now little special attention was given to design guidelines aiming at supporting product development engineers to design products that allow and support control or diagnosis functions. The general trend to ubiquitous computing and the first development steps towards cognitive systems as well as a general trend toward higher product safety, reliability and reduced total cost of ownership (TCO) in many engineering fields lead to a higher importance of control and diagnosis. In this paper a first attempt is made to formulate general valid guidelines how products can be developed in order to allow and to achieve effective and efficient control and diagnosis. The guidelines are elucidated on the example of an automated guided vehicle. One main concern of this paper is the integration of control and diagnosis functionalities into the development of complete systems which include mechanical, electrical and electronic subsystems. For the development of such systems the strategies, methods and tools of systematic product development have attracted significant attention during the last decades. Today, the functionality and safety of most products is to a large degree dependent on control and diagnosis functionalities. Still, there is comparatively little research concentrating on the integration of the development of these functionalities into the overall product development processes. The paper starts with a background describing Systematic Product Development. The second section deals with the product development of the sample product. The third part clarifies the notions monitoring, control and diagnosis. The following parts summarize some insights and formulate first hypotheses concerning control and diagnosis in Systematic Product Development.

  4. Through-space (19) F-(15) N couplings for the assignment of stereochemistry in flubenzimine.

    Science.gov (United States)

    Ghiviriga, Ion; Rubinski, Miles A; Dolbier, William R

    2016-07-01

    Through-space (19) F-(15) N couplings revealed the configuration of flubenzimine, with the CF3 group on N4 pointing towards the lone pair of N5. The (19) F-(15) N coupling constants were measured at natural abundance using a spin-state selective indirect-detection pulse sequence. As (15) N-labelled proteins are routinely synthesized for NMR studies, through-space (19) F-(15) N couplings have the potential to probe the stereochemistry of these proteins by (19) F labelling of some amino acids or can reveal the site of docking of fluorine-containing drugs. Copyright © 2016 John Wiley & Sons, Ltd.

  5. Automation and control of off-planet oxygen production processes

    Science.gov (United States)

    Marner, W. J.; Suitor, J. W.; Schooley, L. S.; Cellier, F. E.

    1990-01-01

    This paper addresses several aspects of the automation and control of off-planet production processes. First, a general approach to process automation and control is discussed from the viewpoint of translating human process control procedures into automated procedures. Second, the control issues for the automation and control of off-planet oxygen processes are discussed. Sensors, instruments, and components are defined and discussed in the context of off-planet applications, and the need for 'smart' components is clearly established.

  6. The metabolic control of schistosome egg production

    Science.gov (United States)

    Pearce, Edward J.; Huang, Stanley Ching-Cheng

    2015-01-01

    Schistosomiasis is a Neglected Tropical Disease caused by infection with trematode parasites of the genus Schistosoma. Despite ongoing treatment programs, the prevalence of schistosomiasis has failed to decline and the disease remains a cause of severe morbidity in millions of people. Understanding the biology of egg production by schistosomes is critical since eggs allow transmission of the infection, and when trapped in host tissues induce the immune responses that are responsible for the pathologic changes that underlie disease development. Unusually among trematodes, adult schistosomes exhibit sexual dimorphism and display a fascinating codependency in that the female is dependent on the male to grow and sexually mature. Thus virgin females are developmentally stunted compared to females from mixed-sex infections and are unable to lay eggs. Moreover, fecund female schistosomes rapidly lose the ability to produce eggs when placed in tissue culture. Here we discuss the metabolic regulation of egg production in schistosomes, and in particular the critical role played by fatty acid oxidation in this process. PMID:25850569

  7. Amino acid biogeo- and stereochemistry in coastal Chilean sediments

    DEFF Research Database (Denmark)

    Lomstein, Bente Aagaard; Jørgensen, Bo Barker; Schubert, Carsten J.;

    2006-01-01

    The spatial distribution of total hydrolysable amino acids (THAA) and amino acid enantiomers (D- and L-forms) was investigated in sediments underlying two contrasting Chilean upwelling regions,: at ~23°S off Antofagasta and at ~36°S off Concepcion. The contribution of amino acids to total organic...... carbon (%TAAC: 7-14%) and total nitrogen (%TAAN: 23-38%) in surface sediments decreased with increasing water depth (from 126 to 1350 m) indicating that organic matter becomes increasingly decomposed in surface sediments at greater water depth. Changes in the ratio between the protein amino acid...... aspartate and its non-protein degradation product β-alanine confirmed this observation. Furthermore, estimates of THAA mineralization showed that sedimentary amino acid reactivity decreased with both increasing water depth as well as progressive degradation status of the organic matter that was incorporated...

  8. A New Mathematical Modeling Technique for Pull Production Control Systems

    Directory of Open Access Journals (Sweden)

    O. Srikanth

    2013-12-01

    Full Text Available The Kanban Control System widely used to control the release of parts of multistage manufacturing system operating under a pull production control system. Most of the work on Kanban Control System deals with multi-product manufacturing system. In this paper, we are proposing a regression modeling technique in a multistage manufacturing system is to be coordinates the release of parts into each stage of the system with the arrival of customer demands for final products. And also comparing two variants stages of the Kanban Control System model and combines with mathematical and Simulink model for the production coordination of parts in an assembly manufacturing systems. In both variants, the production of a new subassembly is authorized only when an assembly Kanban is available. Assembly kanbans become available when finished product is consumed. A simulation environment for the product line system has to generate with the proposed model and the mathematical model have to give implementation against the simulation model in the working platform of MATLAB. Both the simulation and model outputs have provided an in depth analysis of each of the resulting control system for offering model of a product line system.

  9. Controlling nitrous oxide emissions from grassland livestock production systems

    NARCIS (Netherlands)

    Oenema, O.; Gebauer, G.; Rodriguez, M.; Sapek, A.; Jarvis, S.C.; Corré, W.J.; Yamulki, S.

    1998-01-01

    There is growing awareness that grassland livestock production systems are major sources of nitrous oxide (N2O). Controlling these emissions requires a thorough understanding of all sources and controlling factors at the farm level. This paper examines the various controlling factors and proposes

  10. The use of J-coupling as a sole criterion to assign the total absolute stereochemistry of new pyrrolidinone class synthetic analogs, derived from S-pyroglutamic acid

    Science.gov (United States)

    Kellici, Tahsin F.; Ntountaniotis, Dimitrios; Vanioti, Marianna; Golic Grdadolnik, Simona; Simcic, Mihael; Michas, Georgios; Moutevelis-Minakakis, Panagiota; Mavromoustakos, Thomas

    2017-02-01

    During the synthesis of new pyrrolidinone analogs possessing biological activity it is intriguing to assign their absolute stereochemistry as it is well known that drug potency is influenced by the stereochemistry. The combination of J-coupling information with theoretical results was used in order to establish their total stereochemistry when the chiral center of the starting material has known absolute stereochemistry. The J-coupling can be used as a sole criterion for novel synthetic analogs to identify the right stereochemistry. This approach is extremely useful especially in the case of analogs whose 2D NOESY spectra cannot provide this information. Few synthetic examples are given to prove the significance of this approach.

  11. STATISTICAL CONTROL OF PROCESSES AND PRODUCTS IN AGRICULTURE

    Directory of Open Access Journals (Sweden)

    D. Horvat

    2006-06-01

    Full Text Available Fundamental concept of statistical process control is based on decision-making about the process on the basis of comparison of data collected from process with calculated control limits. Statistical process and quality control of agricultural products is used to provide agricultural products that will satisfy customer requirements in a view of quality pretension as well as costumer requirements in a cost price. In accordance with ISO 9000, quality standards for process and products are defined. There are many institutions in Croatia that work in accordance with these standards. Implementation of statistical process control and usage of a control charts can greatly help in convergence to the standards and in decreasing of production costs. To illustrate the above mentioned we tested a work quality of a nozzle at the eighteen meter clutch sprayer.

  12. Engineering Documentation Control Handbook Configuration Management and Product Lifecycle Management

    CERN Document Server

    Watts, Frank B

    2011-01-01

    In this new edition of his widely-used Handbook, Frank Watts, widely recognized for his significant contributions to engineering change control processes, provides a thoroughly practical guide to the implementation and improvement of Engineering Documentation Control (EDC), Product Lifecycle Management and Product Configuration Management (CM). Successful and error-free implementation of EDC/CM is critical to world-class manufacturing. Huge amounts of time are wasted in most product manufacturing environments over EDC/CM issues such as interchangeability, document release and change control -

  13. How stereochemistry influences the taste of wine: Isolation, characterization and sensory evaluation of lyoniresinol stereoisomers.

    Science.gov (United States)

    Cretin, Blandine N; Sallembien, Quentin; Sindt, Lauriane; Daugey, Nicolas; Buffeteau, Thierry; Waffo-Teguo, Pierre; Dubourdieu, Denis; Marchal, Axel

    2015-08-12

    Wine expresses its beauty by sending a sensory message to the taster through molecules coming from grapes, yeast metabolism or oak wood. Among the compounds released during barrel aging, lyoniresinol has been recently reported as a relevant contributor to wine bitterness. As this lignan contains three stereogenic carbons, this work aimed at investigating the influence of stereochemistry on wine taste by combining analytical and sensorial techniques. First, an oak wood extract was screened by Liquid Chromatography-High Resolution Mass Spectrometry to target isomers separable in a symmetric environment and a diastereoisomer called epi-lyoniresinol was isolated for the first time. Then, an original racemic resolution based on natural xylose-derivatives was carried out to obtain lyoniresinol enantiomers. Chiroptical spectroscopic measurements associated with theoretical calculations allowed the unambiguous determination of their absolute configuration. The taste properties of all these stereoisomers revealed that only one lyoniresinol enantiomer is strongly bitter whereas the other one is tasteless and the diastereoisomer is slightly sweet. The presence of these three compounds was established in an oaked Bordeaux wine by chiral and non-chiral chromatography, suggesting the significant influence of stereochemistry on wine taste.

  14. Stereochemistry and conformation of skyllamycin, a non-ribosomally synthesized peptide from Streptomyces sp. Acta 2897.

    Science.gov (United States)

    Schubert, Vivien; Di Meo, Florent; Saaidi, Pierre-Loïc; Bartoschek, Stefan; Fiedler, Hans-Peter; Trouillas, Patrick; Süssmuth, Roderich D

    2014-04-22

    Skyllamycin is a non-ribosomally synthesized cyclic depsipeptide from Streptomyces sp. Acta 2897 that inhibits PDGF-signaling. The peptide scaffold contains an N-terminal cinnamoyl moiety, a β-methylation of aspartic acid, three β-hydroxylated amino acids and one rarely occurring α-hydroxy glycine. With the exception of α-hydroxy glycine, the stereochemistry of the amino acids was assigned by comparison to synthetic reference amino acids applying chiral GC-MS and Marfey-HPLC analysis. The stereochemistry of α-hydroxy glycine, which is unstable under basic and acidic conditions, was determined by conformational analysis, employing a combination of data from NOESY-NMR spectroscopy, simulated annealing and free MD simulations. The simulation procedures were applied for both R- and S-configured α-hydroxy glycine of the skyllamycin structure and compared to the NOESY data. Both methods, simulated annealing and free MD simulations independently support S-configured α-hydroxy glycine thus enabling the assignment of all stereocenters in the structure of skyllamycin and devising the role of two-component flavin dependent monooxygenase (Sky39) as S-selective.

  15. Chiral Cyclobutane β-Amino Acid-Based Amphiphiles: Influence of Cis/Trans Stereochemistry on Solution Self-Aggregation and Recognition.

    Science.gov (United States)

    Sorrenti, Alessandro; Illa, Ona; Pons, Ramon; Ortuño, Rosa M

    2015-09-08

    Novel diastereomeric anionic amphiphiles based on the rigid cyclobutane β-amino acid scaffold have been synthesized and deeply investigated with the aim of generating new functional supramolecular architectures on the basis of the rational design of original amphiphilic molecules and the control of their self-assembly. The main interest has been focused on the effect that cis/trans stereochemistry exerts on their molecular organization and recognition. In diluted solutions, the relative stereochemistry mainly influences the headgroup solvation and anionic-charge stabilization, i.e., better stabilized in the cis diastereoisomer due to intramolecular hydrogen-bonding and/or charge-dipole interactions. This provokes differences in their physicochemical behavior (pKa, cmc, conductivity) as well as in the structural parameters of the spherical micelles formed. Although both diastereoisomers form fibers that evolve with time from the spherical micelles, they display markedly different morphology and kinetics of formation. In the lyotropic liquid crystal domain, the greatest differences are observed at the highest concentrations and can be ascribed to different hydrogen-bonding and molecular packing imposed by the stereochemical constraints. Remarkably, the spherical micelles of the two anionic surfactants show dramatically diverse enantioselection ability for bilirubin enantiomers. In addition, both the surfactants form heteroaggregates with bilirubin at submicellar concentrations but with a different expression of supramolecular chirality. This points out that the unlike relative configuration of the two surfactants influences their chiral recognition ability as well as the fashion in which chirality is expressed at the supramolecular level by controlling the molecular organization in both micellar aggregates and surfactant/bilirubin heteroaggregates. All these differential features can be appropriate and useful for the design and development of new soft materials with

  16. IMPLEMENTATION OF CONTROL CARDS AND SUPPORTING METHOD IN PRODUCTION ENGINEERING

    Directory of Open Access Journals (Sweden)

    Anna WOLNOWSKA

    2012-10-01

    Full Text Available In the article there were presented chosen method associated with statistical control of production processes. Mainly focused on control cards and Pareto‐Lorenz analysis. Showed method were implemented to analysis production process stability of hearing aids in X company (the brand name don’t give because date of production is secret. Researches were made few months after new assembly lines starts‐up. Main aim of researches was defects types identification occurred in production process and determine the scale of effect. Finally received results were satisfactory, i.e. despite of occurred errors, control cards analysis showed that production process of BTE‐type (Behind‐The‐Ear hearing aids was stable.

  17. Optimum Production Control and Workforce Scheduling of Machining Project

    Science.gov (United States)

    Lan, Tian-Syung; Lo, Chih-Yao; Hou, Cheng-I.

    Through the proposed model in this study, the production control with the consideration of workforce scheduling for advanced manufacturing systems becomes realistically and concretely solvable. This study not only meditates the concept of balancing machine productivity and human ability into the objective, but also implements Calculus of Variations to optimize the profit for a deterministic production quantity. In addition, the optimum solutions of dynamic productivity control and workforce scheduling are comprehensively provided. Moreover, the decision criteria for selecting the optimum solution and the sensitivity analysis of the critical variables are fully discussed. This study definitely contributes the applicable strategy to control the productivity and workforce in manufacturing and provides the valuable tool to conclusively optimize the profit of a machining project for operations research in today`s manufacturing industry with profound insight.

  18. Managing unforeseen events in production scheduling and control

    DEFF Research Database (Denmark)

    Arica, E.; Falster, Peter; Hvolby, H. H.

    2016-01-01

    The production planning and control process is performed within complex and dynamic organizations made up of customer expectations, equipment, materials, people, information, and technologies. Changes in both internal and external factors can create a variety of unforeseen events, which make...

  19. Suprachiasmatic Nucleus Neuropeptides and Their Control of Endogenous Glucose Production

    NARCIS (Netherlands)

    Foppen, E; Tan, A A T; Ackermans, M T; Fliers, E; Kalsbeek, A

    2016-01-01

    Defective control of endogenous glucose production is an important factor responsible for hyperglycaemia in the diabetic individual. During the past decade, progressively more evidence has appeared indicating a strong and potentially causal relationship between disturbances of the circadian system a

  20. Advancement in modern approaches to mineral production quality control

    Science.gov (United States)

    Freidina, EV; Botvinnik, AA; Dvornikova, AN

    2017-02-01

    The natural resource potential of mineral deposits is represented by three categories: upside, attainable and investment. A modern methodology is proposed in this paper for production quality control, and its tools aimed at ensuring agreement between the product quality and the market requirements are described. The definitions of the costs of the product quality compliance and incompliance with the consumer requirements are introduced; the latter is suggested to use in evaluating resource potential of mineral deposits at a certain degree of probability.

  1. Virtual Factory Framework for Supporting Production Planning and Control.

    Science.gov (United States)

    Kibira, Deogratias; Shao, Guodong

    2017-01-01

    Developing optimal production plans for smart manufacturing systems is challenging because shop floor events change dynamically. A virtual factory incorporating engineering tools, simulation, and optimization generates and communicates performance data to guide wise decision making for different control levels. This paper describes such a platform specifically for production planning. We also discuss verification and validation of the constituent models. A case study of a machine shop is used to demonstrate data generation for production planning in a virtual factory.

  2. Supervisory controller synthesis for product lines using CIF 3

    NARCIS (Netherlands)

    M.H. ter Beek (Maurice); M.A. Reniers (Michel); E.P. de Vink (Erik Peter)

    2016-01-01

    textabstractUsing the CIF 3 toolset, we illustrate the general idea of controller synthesis for product line engineering for a prototypical example of a family of coffee machines. The challenge is to integrate a number of given components into a family of products such that the resulting behaviour

  3. Dubai to take control of its oil production

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2006-09-15

    The government of Dubai is to take control of the emirate's oil production. From 2nd April, 2007, the foreign consortium responsible for nearly all of Dubai's production will cease to operate the concession and be replaced by a new state-owned company, bringing to an end an era that has lasted over forty years. (author)

  4. Designing pull production control systems : Customization and robustness

    NARCIS (Netherlands)

    Gaury, E.G.A.

    2000-01-01

    In this dissertation we address the issues of selecting and configuring pull production control systems for single-product flowlines. We start with a review of pull systems in the literature, yielding a new classification. Then we propose a novel selection procedure based on a generic system that we

  5. Can Differentiated Production Planning and Control enable both Responsiveness and Efficiency in Food Production?

    Directory of Open Access Journals (Sweden)

    Anita Romsdal

    2014-07-01

    Full Text Available This paper addresses the complex production planning and control (PPC challenges in food supply chains. The study illustrates how food producers' traditional make‐to‐stock (MTS approach is not well suited to meet the trends of increasing product variety, higher demand uncertainty, increasing sales of fresh food products and more demanding customers. The paper proposes a framework for differentiated PPC that combines MTS with make‐to‐order (MTO.The framework matches products with the most appropriate PPC approaches and buffering techniques depending on market and product characteristics. The core idea is to achieve more volume flexibility in the production system by exploiting favourable product and market characteristics (high demand predictability, long customer order leadtime allowances and low product perishability. A case study is used to demonstrate how the framework can enable food producers to achieve efficiency in production, inventory and PPC processes – and simultaneously be responsive to market requirements.

  6. Stereochemistry analysis and comparison of two C(3)-alkyl substituted cyclohexonedicarboxylates with their C(3)-aryl substituted analogues

    Science.gov (United States)

    Chen, Chao-Yue; Wang, Qi; Zhu, Bing-Long; Zhao, Wen-Jie; Hu, Jin-Song

    2016-03-01

    Two representative C(3)-alkyl substituted cyclohexonedicarboxylates (4a and 4b) were synthesized and their conformational features were investigated by single crystal X-ray crystallography for the first time. These stereochemistry results of 4a and 4b were compared with those obtained from the earlier research of C(3)-aryl substituted analogues (1-3).

  7. Nanoscale amphiphilic macromolecules with variable lipophilicity and stereochemistry modulate inhibition of oxidized low-density lipoprotein uptake.

    Science.gov (United States)

    Poree, Dawanne E; Zablocki, Kyle; Faig, Allison; Moghe, Prabhas V; Uhrich, Kathryn E

    2013-08-12

    Amphiphilic macromolecules (AMs) based on carbohydrate domains functionalized with poly(ethylene glycol) can inhibit the uptake of oxidized low density lipoprotein (oxLDL) and counteract foam cell formation, a key characteristic of early atherogenesis. To investigate the influence of lipophilicity and stereochemistry on the AMs' physicochemical and biological properties, mucic acid-based AMs bearing four aliphatic chains (2a) and tartaric acid-based AMs bearing two (2b and 2l) and four aliphatic chains (2g and 2k) were synthesized and evaluated. Solution aggregation studies suggested that both the number of hydrophobic arms and the length of the hydrophobic domain impact AM micelle sizes, whereas stereochemistry impacts micelle stability. 2l, the meso analogue of 2b, elicited the highest reported oxLDL uptake inhibition values (89%), highlighting the crucial effect of stereochemistry on biological properties. This study suggests that stereochemistry plays a critical role in modulating oxLDL uptake and must be considered when designing biomaterials for potential cardiovascular therapies.

  8. Structures, Reactions, and Mechanisms: Stereochemistry in the Broadest Sense at the 51st Bürgenstock Conference.

    Science.gov (United States)

    Fleischer, Ivana

    2016-07-18

    Tradition and innovation: The 51st Bürgenstock Conference on Stereochemistry took place from May 1-6, 2016 and offered its usual mixture of impressive science and superb discussions in a wonderful atmosphere. In the Meeting Review, Ivana Fleischer outlines the program.

  9. FPGA based Control of a Production Cell System

    NARCIS (Netherlands)

    Groothuis, Marcel A.; Zuijlen, van Jasper J.P.; Broenink, Jan F.

    2008-01-01

    Most motion control systems for mechatronic systems are implemented on digital computers. In this paper we present an FPGA based solution implemented on a low cost Xilinx Spartan III FPGA. A Production Cell setup with multiple parallel operating units is chosen as a test case. The embedded control s

  10. Modeling and control for closed environment plant production systems

    Science.gov (United States)

    Fleisher, David H.; Ting, K. C.; Janes, H. W. (Principal Investigator)

    2002-01-01

    A computer program was developed to study multiple crop production and control in controlled environment plant production systems. The program simulates crop growth and development under nominal and off-nominal environments. Time-series crop models for wheat (Triticum aestivum), soybean (Glycine max), and white potato (Solanum tuberosum) are integrated with a model-based predictive controller. The controller evaluates and compensates for effects of environmental disturbances on crop production scheduling. The crop models consist of a set of nonlinear polynomial equations, six for each crop, developed using multivariate polynomial regression (MPR). Simulated data from DSSAT crop models, previously modified for crop production in controlled environments with hydroponics under elevated atmospheric carbon dioxide concentration, were used for the MPR fitting. The model-based predictive controller adjusts light intensity, air temperature, and carbon dioxide concentration set points in response to environmental perturbations. Control signals are determined from minimization of a cost function, which is based on the weighted control effort and squared-error between the system response and desired reference signal.

  11. Inhibitory Control Predicts Language Switching Performance in Trilingual Speech Production

    Science.gov (United States)

    Linck, Jared A.; Schwieter, John W.; Sunderman, Gretchen

    2012-01-01

    This study investigated the role of domain-general inhibitory control in trilingual speech production. Taking an individual differences approach, we examined the relationship between performance on a non-linguistic measure of inhibitory control (the Simon task) and a multilingual language switching task for a group of fifty-six native English (L1)…

  12. [Pharmaceutical product quality control and good manufacturing practices].

    Science.gov (United States)

    Hiyama, Yukio

    2010-01-01

    This report describes the roles of Good Manufacturing Practices (GMP) in pharmaceutical product quality control. There are three keys to pharmaceutical product quality control. They are specifications, thorough product characterization during development, and adherence to GMP as the ICH Q6A guideline on specifications provides the most important principles in its background section. Impacts of the revised Pharmaceutical Affairs Law (rPAL) which became effective in 2005 on product quality control are discussed. Progress of ICH discussion for Pharmaceutical Development (Q8), Quality Risk Management (Q9) and Pharmaceutical Quality System (Q10) are reviewed. In order to reconstruct GMP guidelines and GMP inspection system in the regulatory agencies under the new paradigm by rPAL and the ICH, a series of Health Science studies were conducted. For GMP guidelines, product GMP guideline, technology transfer guideline, laboratory control guideline and change control system guideline were written. For the GMP inspection system, inspection check list, inspection memo and inspection scenario were proposed also by the Health Science study groups. Because pharmaceutical products and their raw materials are manufactured and distributed internationally, collaborations with other national authorities are highly desired. In order to enhance the international collaborations, consistent establishment of GMP inspection quality system throughout Japan will be essential.

  13. Carbohydrate Stereochemistry.

    Science.gov (United States)

    Shallenberger, Robert S.; Wienen, Wanda J.

    1989-01-01

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

  14. Primary production control of methane emission from wetlands

    Science.gov (United States)

    Whiting, G. J.; Chanton, J. P.

    1993-01-01

    Based on simultaneous measurements of CO2 and CH4 exchange in wetlands extending from subarctic peatlands to subtropical marshes, a positive correlation between CH4 emission and net ecosystem production is reported. It is suggested that net ecosystem production is a master variable integrating many factors which control CH4 emission in vegetated wetlands. It is found that about 3 percent of the daily net ecosystem production is emitted back to the atmosphere as CH4. With projected stimulation of primary production and soil microbial activity in wetlands associated with elevated atmospheric CO2 concentration, the potential for increasing CH4 emission from inundated wetlands, further enhancing the greenhouse effect, is examined.

  15. Assignment of the Stereochemistry and Anomeric Configuration of Sugars within Oligosaccharides Via Overlapping Disaccharide Ladders Using MSn

    Science.gov (United States)

    Konda, Chiharu; Londry, Frank A.; Bendiak, Brad; Xia, Yu

    2014-08-01

    A systematic approach is described that can pinpoint the stereo-structures (sugar identity, anomeric configuration, and location) of individual sugar units within linear oligosaccharides. Using a highly modified mass spectrometer, dissociation of linear oligosaccharides in the gas phase was optimized along multiple-stage tandem dissociation pathways (MSn, n = 4 or 5). The instrument was a hybrid triple quadrupole/linear ion trap mass spectrometer capable of high-efficiency bidirectional ion transfer between quadrupole arrays. Different types of collision-induced dissociation (CID), either on-resonance ion trap or beam-type CID could be utilized at any given stage of dissociation, enabling either glycosidic bond cleavages or cross-ring cleavages to be maximized when wanted. The approach first involves optimizing the isolation of disaccharide units as an ordered set of overlapping substructures via glycosidic bond cleavages during early stages of MSn, with explicit intent to minimize cross-ring cleavages. Subsequently, cross-ring cleavages were optimized for individual disaccharides to yield key diagnostic product ions ( m/ z 221). Finally, fingerprint patterns that establish stereochemistry and anomeric configuration were obtained from the diagnostic ions via CID. Model linear oligosaccharides were derivatized at the reducing end, allowing overlapping ladders of disaccharides to be isolated from MSn. High confidence stereo-structural determination was achieved by matching MSn CID of the diagnostic ions to synthetic standards via a spectral matching algorithm. Using this MSn ( n = 4 or 5) approach, the stereo-structures, anomeric configurations, and locations of three individual sugar units within two pentasaccharides were successfully determined.

  16. Stereochemistry and Mechanism of Undecylprodigiosin Oxidative Carbocyclization to Streptorubin B by the Rieske Oxygenase RedG.

    Science.gov (United States)

    Withall, David M; Haynes, Stuart W; Challis, Gregory L

    2015-06-24

    The prodiginines are a group of specialized metabolites that share a 4-methoxypyrrolyldipyrromethene core structure. Streptorubin B is a structurally remarkable member of the prodiginine group produced by Streptomyces coelicolor A3(2) and other actinobacteria. It is biosynthesized from undecylprodigiosin by an oxidative carbocyclization catalyzed by the Rieske oxygenase-like enzyme RedG. Undecylprodigiosin derives from the RedH-catalyzed condensation of 2-undecylpyrrole and 4-methoxy-2, 2'-bipyrrole-5-carboxaldehyde (MBC). To probe the mechanism of the RedG-catalyzed reaction, we synthesized 2-(5-pentoxypentyl)-pyrrole, an analogue of 2-undecylpyrrole with an oxygen atom next to the site of C-C bond formation, and fed it, along with synthetic MBC, to Streptomyces albus expressing redH and redG. This resulted in the production of the 6'-oxa analogue of undecylprodigiosin. In addition, a small amount of a derivative of this analogue lacking the n-pentyl group was produced, consistent with a RedG catalytic mechanism involving hydrogen abstraction from the alkyl chain of undecylprodigiosin prior to pyrrole functionalization. To investigate the stereochemistry of the RedG-catalyzed oxidative carbocyclization, [7'-(2)H](7'R)-2-undecylpyrrole and [7'-(2)H](7'S)-2-undecylpyrrole were synthesized and fed separately, along with MBC, to S. albus expressing redH and redG. Analysis of the extent of deuterium incorporation into the streptorubin B produced in these experiments showed that the pro-R hydrogen atom is abstracted from C-7' of undecylprodigiosin and that the reaction proceeds with inversion of configuration at C-7'. This contrasts sharply with oxidative heterocyclization reactions catalyzed by other nonheme iron-dependent oxygenase-like enzymes, such as isopenicillin N synthase and clavaminate synthase, which proceed with retention of configuration at the carbon center undergoing functionalization.

  17. Run-to-run product quality control of batch processes

    Institute of Scientific and Technical Information of China (English)

    JIA Li; SHI Ji-ping; CHENG Da-shuai; CHIU Min-sen

    2009-01-01

    Batch processes have been increasingly used in the production of low volume and high value added products.Consequently,optimization control in batch processes is crucial in order to derive the maximum benefit.In this paper,a run-to-run product quality control based on iterative learning optimization control is developed.Moreover,a rigorous theorem is proposed and proven in this paper,which states that the tracking error under the optimal iterative learning control (ILC) law can converge to zero.In this paper,a typical nonlinear batch continuous stirred tank reactor (CSTR) is considered,and the results show that the performance of trajectory tracking is gradually improved by the ILC.

  18. The methods that college students use to answer questions about stereochemistry involving spatial ability

    Science.gov (United States)

    Strange de Soria, Luise Ethelyn

    Introduction. The research problem investigated involved determining the spatial techniques used by students when they solved problems relating to stereochemistry using both traditional and non-traditional techniques. The main reason for undertaking this study was to determine how to help students invoke their spatial ability in solving problems during their organic chemistry courses. The project allowed students to generate their own understanding of the material, to gain experience in order to increase their knowledge, and to be actively involved in the learning process in order for true understanding to take place. Methods. The qualitative methodology for the project included a background questionnaire and the Purdue Visualization of Rotations Exam to determine the five students to be interviewed. The class participated in three multimedia lectures, an in-class assignment, and an on-line homework activity, which allowed multiple ways of incorporating the material. These activities included hand-drawing structures, making non-traditional models as well as traditional models, and computer related exercises that required differing aspects of spatial ability and engagement. Five students participated in an individual and small group interview in which rotation ability as well as visualization ability was assessed using physical molecular models as well as computer models. Results. This study is significant for the field of science education and chemistry because it determined that students with varying levels of spatial ability preferred different tools and used different skills when answering questions about stereochemistry that require spatial ability. There was a pronounced difference in the ability of low and high spatial ability students to draw and make structures that required three-dimensional aspects. A distinct preference for working with the physical model kit over the computer-enhanced program was also noted. An online resource for instructors and

  19. Control design for an autonomous wind based hydrogen production system

    Energy Technology Data Exchange (ETDEWEB)

    Valenciaga, F.; Evangelista, C.A. [CONICET, Laboratorio de Electronica Industrial Control e Instrumentacion (LEICI), Facultad de Ingenieria, Universidad Nacional de La Plata, CC.91, C.P. 1900, La Plata (Argentina)

    2010-06-15

    This paper presents a complete control scheme to efficiently manage the operation of an autonomous wind based hydrogen production system. This system comprises a wind energy generation module based on a multipolar permanent magnet synchronous generator, a lead-acid battery bank as short term energy storage and an alkaline von Hoerner electrolyzer. The control is developed in two hierarchical levels. The higher control level or supervisor control determines the general operation strategy for the whole system according to the wind conditions and the state of charge of the battery bank. On the other hand, the lower control level includes the individual controllers that regulate the respective module operation assuming the set-points determined by the supervisor control. These last controllers are approached using second-order super-twisting sliding mode techniques. The performance of the closed-loop system is assessed through representative computer simulations. (author)

  20. One-of-a-kind Production: Controller Algorithms for Real-time Control

    DEFF Research Database (Denmark)

    Ørum-Hansen, Claus

    PhD Dissertation.IPS2-programme - Integrated Production Systems - supportet by the Danish Technical Research Council, STVF.The project is a part of the IPS 2 research Programmme - Integrated Production System - with focus on one-of-a-kind production.The research area deals with controller...... algorithms for real-time control. The work includes practical cases from ship design and manufacturing. Cooperation with Odense Steel Shipyard....

  1. Methodical Grounds of Managing the Product Quality Control

    Directory of Open Access Journals (Sweden)

    Shapoval Olena A.

    2014-01-01

    Full Text Available The article analyses the modern state of products quality control management. It justifies a necessity of organisation of the quality control system under conditions of uninterrupted flow line production. It reveals problems connected with a low level of the products quality control management. It forms a set of factors of internal and external environments, which should be taken into account in the process of selection of a type of managerial actions by the products quality control. It considers specific features of identification of the most important factors at an enterprise on the basis of use of the matrix of strategic SWOT analysis. It offers a procedure of identification of a general assessment of factors of influence. It analyses a mechanism of use of main conceptual models, which reflect the system nature of quality management in an organisation – quality pyramids and quality loops. It proves a necessity of application of a principally new scheme of relations between the customer and enterprise, which envisages that requirements of the quality management system focus not on control and screening of semi-finished products, but on creation of conditions that exclude rejects. It considers the role of ISO 9000 in the system of quality management, which recommend the customers to make a preliminary assessment of activity of the producing enterprise.

  2. Automated Identification and Classification of Stereochemistry: Chirality and Double Bond Stereoisomerism

    CERN Document Server

    Teixeira, Ana L; Falcao, Andre O

    2013-01-01

    Stereoisomers have the same molecular formula and the same atom connectivity and their existence can be related to the presence of different three-dimensional arrangements. Stereoisomerism is of great importance in many different fields since the molecular properties and biological effects of the stereoisomers are often significantly different. Most drugs for example, are often composed of a single stereoisomer of a compound, and while one of them may have therapeutic effects on the body, another may be toxic. A challenging task is the automatic detection of stereoisomers using line input specifications such as SMILES or InChI since it requires information about group theory (to distinguish stereoisomers using mathematical information about its symmetry), topology and geometry of the molecule. There are several software packages that include modules to handle stereochemistry, especially the ones to name a chemical structure and/or view, edit and generate chemical structure diagrams. However, there is a lack o...

  3. Structure-activity relationships in aminosterol antibiotics: the effect of stereochemistry at the 7-OH group.

    Science.gov (United States)

    Tessema, Tsemre-Dingel; Gassler, Frank; Shu, Youheng; Jones, Stephen; Selinsky, Barry S

    2013-06-01

    Squalamine and three aminosterol analogs have been shown to inhibit bacterial cell growth and induce lysis of large unilamellar phospholipid vesicles. The analogs differ in the identity of the polyamine attached at C3 of the sterol, and the stereochemistry of a hydroxyl substituent at C7. Analogs with a tetraammonium spermine polyamine are somewhat more active than analogs with a shorter trisammonium spermidine polyamine, and analogs with an axial (α) hydroxyl substituent at C7 are more active than analogs with the corresponding equatorial (β) hydroxyl group. There is some variability noted; the 7β-OH spermine analog is the most active compound against Escherichia coli, but the least effective against Pseudomonas aeruginosa. Lytic activity correlates well with antimicrobial activity of the compounds, but the lytic activity varies with the phospholipid composition of the vesicles.

  4. Product market competition, ultimate controlling structure and related party transactions

    Directory of Open Access Journals (Sweden)

    Shenglan Chen

    2012-12-01

    Full Text Available Previous studies have shown that product market competition has an important effect on corporate strategies and internal governance mechanisms. Using a sample of China’s listed firms from 2004 to 2009, we explore the relationship between product market competition and normal related party transactions and find a significant positive relationship. In addition, we investigate the substitutive effect of product market competition and the cash flow rights owned by ultimate controlling shareholders on the extent of normal related party transactions. In particular, our results suggest a positive relationship between the ultimate controlling shareholders’ cash flow rights and normal related party transactions that is strongest in noncompetitive industries and weakens as product market competition increases.

  5. Enantiomeric HPLC resolution and absolute stereochemistry assignment of a new poligamain derivative.

    Science.gov (United States)

    Pistolozzi, M; Royo, V; Pereira, A C; Silva, M L A; Silva, R; Cunha, W R; Vaconcelos, K; Cass, Q B; Martins, C H G; Bastos, J K; Varchi, G; Guerrini, A; Bertucci, C

    2013-03-05

    A new aryltetralin lignan derivative, 1, was obtained by reacting dimethyl succinate and piperonal, furnishing the lactone 4-(3',4'-methylenedioxybenzyl)-4,5-dihydro-2(3H)-furanone, which was reacted once again with piperonal and LDA to give the dibenzylbutirolactone 7-hydroxyhinokinin. The cyclization of 7-hydroxyhinokinin into polygamain occurred in the presence of trifluoroacetic acid. The reduction of the furanic ring of polygamain was done by its reaction with DIBAL in THF, furnishing the diol functionalized lignin derivative 1 as single diastereomer. The enantiomeric fractions of 1 were obtained by preparative enantioselective HPLC. The absolute stereochemistry was assigned by electronic circular dichroism (ECD) and nuclear magnetic resonance (NMR) spectroscopy. An all-trans relative configuration was determined by NMR on the bases of ¹H coupling constants and nuclear Overhauser effect (n.O.e.) experiments. The absolute configuration at C1 was assigned on the basis of the ECD sign at 296 nm by comparison to the ECD spectra of structural analogues with defined stereochemistry. The assignment of the absolute configuration was confirmed by applying the exciton chirality method to the well-defined ECD couplets at 285 and 200 nm allied to the two electronic transitions L(b) and B(b) of the aromatic moieties, respectively. Rac-1 and its enantiomeric isomers were evaluated against important bacteria responsible for dental caries. The best results obtained for the (1R,2S,3S) isomer were against Streptococcus mutans (250 μM), Streptococcus salivarius (250 μM), Streptococcus sobrinus (280 μM) and Streptococcus mitis (280 μM). The (1S,2R,3R) isomer was active only against Streptococcus sanguinis (280 μM). The enantiomeric mixture was less active than the (1R,2S,3S) isomer.

  6. Rhizobacterial characterization for quality control of eucalyptus biogrowth promoter products

    OpenAIRE

    Talyta Galafassi Zarpelon; Lúcio Mauro da Silva Guimarães; Poliane Alfenas-Zerbini; Eli Sidney Lopes; Reginaldo Gonçalves Mafia; Acelino Couto Alfenas

    2016-01-01

    Abstract Plant growth-promoting rhizobacteria strains from special formulations have been used to optimize eucalyptus cutting production. To undertake quality control for the formulated products, the rhizobacterial strains should be characterized to assess their purity and authentication. In the present study, we characterized nine strains of rhizobacteria, including three Bacillus subtilis (S1, S2 and 3918), two Pseudomonas sp. (MF4 and FL2), P. putida (MF2), P. fulva (Ca), Frateuria auranti...

  7. Inversion of the stereochemistry around the sulfur atom of the axial methionine side chain through alteration of amino acid side chain packing in Hydrogenobacter thermophilus cytochrome C552 and its functional consequences.

    Science.gov (United States)

    Tai, Hulin; Tonegawa, Ken; Shibata, Tomokazu; Hemmi, Hikaru; Kobayashi, Nagao; Yamamoto, Yasuhiko

    2013-07-16

    In cytochrome c, the coordination of the axial Met Sδ atom to the heme Fe atom occurs in one of two distinctly different stereochemical manners, i.e., R and S configurations, depending upon which of the two lone pairs of the Sδ atom is involved in the bond; hence, the Fe-coordinated Sδ atom becomes a chiral center. In this study, we demonstrated that an alteration of amino acid side chain packing induced by the mutation of a single amino acid residue, i.e., the A73V mutation, in Hydrogenobacter thermophilus cytochrome c552 (HT) forces the inversion of the stereochemistry around the Sδ atom from the R configuration [Travaglini-Allocatelli, C., et al. (2005) J. Biol. Chem. 280, 25729-25734] to the S configuration. Functional comparison between the wild-type HT and the A73V mutant possessing the R and S configurations as to the stereochemistry around the Sδ atom, respectively, demonstrated that the redox potential (Em) of the mutant at pH 6.00 and 25 °C exhibited a positive shift of ∼20 mV relative to that of the wild-type HT, i.e., 245 mV, in an entropic manner. Because these two proteins have similar enthalpically stabilizing interactions, the difference in the entropic contribution to the Em value between them is likely to be due to the effect of the conformational alteration of the axial Met side chain associated with the inversion of the stereochemistry around the Sδ atom due to the effect of mutation on the internal mobility of the loop bearing the axial Met. Thus, the present study demonstrated that the internal mobility of the loop bearing the axial Met, relevant to entropic control of the redox function of the protein, is affected quite sensitively by the contextual stereochemical packing of amino acid side chains in the proximity of the axial Met.

  8. Discrimination of cheese products for authenticity control by infrared spectroscopy.

    Science.gov (United States)

    Hruzikova, Jana; Milde, David; Krajancova, Pavla; Ranc, Vaclav

    2012-02-22

    Quality and authenticity control serve as the customers' and manufacturers' insurance, and thus the development of analytical tools providing these tasks represents an important step of each product development. The control of authenticity in food manufacturing is even more important due to the direct influence of its products on the health of the population. This study sought to develop an easy to use and robust method for the authenticity control of cheese products. The method is based on the measurement of infrared spectra of the gas phase obtained by heating of selected cheese under controlled conditions. Two different procedures, that is, treatment of samples in a desiccator and their freeze-drying, were compared, and also various temperatures and heating times were studied. It was found that suitable fingerprint infrared spectra can be obtained by both techniques; however, freeze-drying offered faster analysis times. The sample heating temperature and time were evaluated using advanced statistical approaches, and it was found that suitable results could be obtained using 120 °C heating for 90 min. This method was tested for the authenticity control of two cheese families, Tvaruzky and Romadur, for which four cheese products were evaluated and successfully discriminated for each family. This method can be potentially used as a cheap and easy to use alternative to other commercially available options.

  9. Viewing hybrid systems as products of control systems and automata

    Science.gov (United States)

    Grossman, R. L.; Larson, R. G.

    1992-01-01

    The purpose of this note is to show how hybrid systems may be modeled as products of nonlinear control systems and finite state automata. By a hybrid system, we mean a network of consisting of continuous, nonlinear control system connected to discrete, finite state automata. Our point of view is that the automata switches between the control systems, and that this switching is a function of the discrete input symbols or letters that it receives. We show how a nonlinear control system may be viewed as a pair consisting of a bialgebra of operators coding the dynamics, and an algebra of observations coding the state space. We also show that a finite automata has a similar representation. A hybrid system is then modeled by taking suitable products of the bialgebras coding the dynamics and the observation algebras coding the state spaces.

  10. Chinese vaccine products go global: vaccine development and quality control.

    Science.gov (United States)

    Xu, Miao; Liang, Zhenglun; Xu, Yinghua; Wang, Junzhi

    2015-05-01

    Through the continuous efforts of several generations, China has become one of the few countries in the world that is capable of independently addressing all the requirements by the Expanded Program on Immunization. Regulatory science is applied to continuously improve the vaccine regulatory system. Passing the prequalification by WHO has allowed Chinese vaccine products to go global. Chinese vaccine products not only secure disease prevention and control domestically but also serve the needs for international public health. This article describes the history of Chinese vaccine development, the current situation of Chinese vaccine industry and its contribution to the prevention and control of infectious diseases. We also share our experience of national quality control and vaccine regulation during the past decades. China's experience in vaccine development and quality control can benefit other countries and regions worldwide, including the developing countries.

  11. STRATEGIES OF PRODUCTION CONTROL AS TOOLS OF EFFICIENT MANAGEMENT OF PRODUCTION ENTERPRISES

    Directory of Open Access Journals (Sweden)

    Mateusz BUDYNEK

    2016-01-01

    Full Text Available The paper discusses the problem of principle methods of production control as a strategy supporting the production system and stimulating efficient solutions in respect management in production enterprises. The article describes MRP, ERP, JIT, KANBAN and TOC methods and focuses on their main goals, principles of functioning as well as benefits re-sulting from their application. The methods represent two diverse strategies of production control, i.e. pull and push strategies. Push strategies are used when the plans apply to the first and principle part of production and are based on the demand forecasts. Pull strategies are used when all planning decisions apply to the final stage and depend on the actual demand or orders from customers.

  12. Compulsory licensing, price controls, and access to patented foreign products

    OpenAIRE

    Eric Bond; Kamal Saggi

    2012-01-01

    Motivated by existing multilateral rules regarding intellectual property, we develop a North-South model to highlight the dual roles price controls and compulsory licensing play in determining Southern access to a patented Northern product. The Northern patent-holder chooses whether and how to work its patent in the South (either via entry or voluntarily licensing) while the South determines the price control and whether to issue a compulsory license. The threat of compulsory licensing benefi...

  13. Control of Listeria monocytogenes in food production plants

    Directory of Open Access Journals (Sweden)

    Dimitrijević Mirjana

    2008-01-01

    Full Text Available L. monocytogenes has been established in different plants for the production of food, including dairy plants, abattoirs, plants for the processing of fish, as well as those for the production of ready-to-eat (RTE food and this fact is being considered as the primary mechanism of food contamination with this bacteria. There is also the factor of numerous and diverse contaminated production equipment, because it has certain parts that are inaccessible for the necessary cleaning and disinfection. The temperature, position, as well as the material of the work surface are also linked to the contamination of plants with this bacteria. Investigations carried out so far have helped toward the better understanding of the manner and time of contamination of food items in the course of the production process, but there are still unresolved problems, including most certainly the biggest one - the adherence of bacteria and the creation of a biofilm, when the bacteria is in that condition more resistant to so-called stress factors which are usually used in the food industry for the purpose of decontamination of the surfaces with which foods come into contact. The control of L. monocytogenes in food production plants is possible primarily by using an integrated programme, compatible with the systems Hazard Analysis Critical Control Point (HACCP and Good Hygiene Practice (GHP, necessary in the production of food that is safe for the consumer. Essentially, the control measures that can contribute to reducing the incidence of findings of L.monocytogenes in the finished product, as well as the reducing of the level of contamination with this bacteria are linked, on the one hand, with hygiene procedures in the production process, and, on the other, with the applied technological procedures.

  14. Lactate dehydrogenase has no control on lactate production but has a strong negative control on formate production in Lactococcus lactis

    DEFF Research Database (Denmark)

    Andersen, H.W.; Pedersen, M.B.; Hammer, Karin;

    2001-01-01

    a homolactic pattern of fermentation. Only after lactate dehydrogenase activity was reduced ninefold compared to the wild-type was the growth rate significantly affected, and the ldh mutants started to produce mixed-acid products (formate, acetate, and ethanol in addition to lactate). Flux control coefficients...... were determined and it was found that lactate dehydrogenase exerted virtually no control on the glycolytic flux at the wild-type enzyme level and also not on the flux catalyzed by the enzyme itself, i.e. on the lactate production. As expected, the flux towards the mixed-acid products was strongly...... enhanced in the strain deleted for lactate dehydrogenase. What is more surprising is that the enzyme had a strong negative control (C- LDH(F1)J=-1.3) on the flux to formate at the wild-type level of lactate dehydrogenase. Furthermore, we showed that L. lactis has limited excess of capacity of lactate...

  15. Climatic change controls productivity variation in global grasslands.

    Science.gov (United States)

    Gao, Qingzhu; Zhu, Wenquan; Schwartz, Mark W; Ganjurjav, Hasbagan; Wan, Yunfan; Qin, Xiaobo; Ma, Xin; Williamson, Matthew A; Li, Yue

    2016-05-31

    Detection and identification of the impacts of climate change on ecosystems have been core issues in climate change research in recent years. In this study, we compared average annual values of the normalized difference vegetation index (NDVI) with theoretical net primary productivity (NPP) values based on temperature and precipitation to determine the effect of historic climate change on global grassland productivity from 1982 to 2011. Comparison of trends in actual productivity (NDVI) with climate-induced potential productivity showed that the trends in average productivity in nearly 40% of global grassland areas have been significantly affected by climate change. The contribution of climate change to variability in grassland productivity was 15.2-71.2% during 1982-2011. Climate change contributed significantly to long-term trends in grassland productivity mainly in North America, central Eurasia, central Africa, and Oceania; these regions will be more sensitive to future climate change impacts. The impacts of climate change on variability in grassland productivity were greater in the Western Hemisphere than the Eastern Hemisphere. Confirmation of the observed trends requires long-term controlled experiments and multi-model ensembles to reduce uncertainties and explain mechanisms.

  16. Preliminary Screening of Potential Control Products against Drosophila suzukii

    Directory of Open Access Journals (Sweden)

    Andrew G. S. Cuthbertson

    2014-06-01

    Full Text Available The first recording of Drosophila suzukii in the UK occurred in the south of England during August 2012. Since then sticky traps have continued to record the presence of individuals. Several products (both chemical and biological were investigated for their efficacy against different life-stages of the pest. Both direct and indirect exposure to control products was assessed. Spinosad, chlorantraniliprole and the experimental product, TA2674, showed excellent potential as control agents when used as either a pre- or post-dipping treatment for blueberries with mortalities of 100%, 93% and 98% mortality, respectively, being achieved following pre-treatment. Direct spray application of all products tested had limited impact upon adult flies. Highest mortality (68% was achieved following direct application of TA2674. Entomopathogenic agents (nematodes and fungi tested appeared to reduce fly population development (ranges of 34–44% mortality obtained but would seem unable to eradicate outbreaks. The potential of the tested products to control D. suzukii is discussed.

  17. Tobacco Products Directive - new opportunities for EU tobacco control

    Directory of Open Access Journals (Sweden)

    Anna-Eva Ampelas

    2016-03-01

    Full Text Available The Tobacco Products Directive 2014/40/EU was adopted in 2014 and needs to be transposed by Member States by 20 May 2016. It sets out ambitious tobacco control measures in the areas of ingredients, packaging & labelling, electronic cigarettes and tracking & tracing. The new Directive focuses on preventing young people from taking up smoking.

  18. Integrated product definition representation for agile numerical control applications

    Energy Technology Data Exchange (ETDEWEB)

    Simons, W.R. Jr.; Brooks, S.L.; Kirk, W.J. III; Brown, C.W.

    1994-11-01

    Realization of agile manufacturing capabilities for a virtual enterprise requires the integration of technology, management, and work force into a coordinated, interdependent system. This paper is focused on technology enabling tools for agile manufacturing within a virtual enterprise specifically relating to Numerical Control (N/C) manufacturing activities and product definition requirements for these activities.

  19. Tire Production and Pollution Control. Environmental Education Curriculum. Revised.

    Science.gov (United States)

    Topeka Public Schools, KS.

    This unit was developed to introduce secondary students to the many facets of a typical, large manufacturing plant - the Topeka Goodyear Tire and Rubber Company - in an effort to increase awareness of sound environmental practices in industry. Its five major foci include the production of tires and quality control procedures; applications of…

  20. Production planning and control in SMEs : time for change

    NARCIS (Netherlands)

    Land, M.J.; Gaalman, G.J.C.

    2009-01-01

    This study aims to provide a profound picture of where existing production planning and control (PPC) concepts fail in small to medium sized make-to-order (MTO) companies. While several studies have discussed the specific requirements of small and medium sized enterprises (SMEs) through surveys or

  1. Efficacy of potato seeds disinfection products to control Erwinia spp.

    Science.gov (United States)

    Dupuis, B; Garcia, N; Boels, G

    2008-01-01

    Erwinia spp. provokes soft rot on potato tubers during storage. No disinfection products are available on the market in the European Union to control these bacteria. We tested 3 products presented as good candidates to cure potato tubers from bacterial diseases. First, Anthium 500 (Du Pont de Nemours) a product based on chlorine dioxyde, then Phostrol (Nufarm) with phosphoric acid as a.i. and finally Solucuivre (Proval), a copper based product. We firstly managed disinfection trials: high Erwinia contaminated potato seed samples were treated by immersion and were then incubated, we observed the percentage of tubers rotting. Secondly, we managed protection trials: protected healthy tubers were incubated during 23 days in contact with rotting tubers. We evaluated weight loss after symptoms development. No tested product was effective to control Erwinia spp. on seed tubers in our trials conditions. Furthermore, we observed more rot development after Phostrol and Solucuivre application. We suppose that the product couldn't reach the latent bacteria and weakened the tubers. No protection effect was observed.

  2. Quality control throughout the production process of infant food.

    Science.gov (United States)

    Hamrin, Pia; Hoeft, Birgit

    2012-01-01

    The manufacture of infant food is a highly complex process and needs an effective quality control beyond classical in-process parameters and a final microbiological analysis. To ensure a safe end -product, various tools, such as the Hazard Analysis Critical Control Points (HACCP), have been developed to facilitate the management of food safety. Every single infant formula ingredient must have an excellent quality and safety approach because even if an ingredient is used in very small quantities in a single product, serious consequences may arise if the quality and product safety are not taken seriously by the ingredient manufacturer. The purpose of this article was twofold: firstly, to briefly describe existing Quality Management Systems and, secondly, to highlight the consequences of non-quality.

  3. Control of corrosion product transport in PWR secondary cycles

    Energy Technology Data Exchange (ETDEWEB)

    Sawochka, S.G.; Pearl, W.L. [NWT Corp., San Josa, CA (United States); Passell, T.O.; Welty, C.S. [Electric Power Research Institute, Palo Alto, CA (United States)

    1992-12-31

    Transport of corrosion products to PWR steam generators by the feedwater leads to sludge buildup on the tubesheets and fouling of tube-to-tube support crevices. In these regions, chemical impurities concentrate and accelerate tubing corrosion. Deposit buildup on the tubes also can lead to power generation limitations and necessitate chemical cleaning. Extensive corrosion product transport data for PWR secondary cycles has been developed employing integrating sampling techniques which facilitate identification of major corrosion product sources and assessments of the effectiveness of various control options. Plant data currently are available for assessing the impact of factors such as pH, pH control additive, materials of construction, blowdown, condensate treatment, and high temperature drains and feedwater filtration.

  4. Method of technological control of proportional electromagnets for control systems of their production

    Science.gov (United States)

    Lankin, A. M.; Lankin, M. V.; Lankina, M. Y.

    2017-02-01

    This article describes the algorithm of the method of technological control of proportional solenoids to control their production process. An important element in the process of production of proportional solenoids is to identify deviations from the nominal mode of its occurrence. This situation shows the relevance of developing a method of technological control of proportional solenoids providing information on process control in a short time. The proposed algorithm consists of four steps: measuring the dynamic characteristics of the magnetization of electromagnet testing, the use of principal component analysis to reduce the dimension of the analyzed information, the classification of products by the condition and sub-standards, the definition of the numerical values of the manufacturing process variations using a calibration method. This approach allows us to determine the type and the degree of impairment of the mode of the process that will lead to effective management of the production process of the electromagnetic actuators.

  5. DFT Investigation of the Mechanism and Stereochemistry of Electrophilic Transannular Addition Reaction of Chlorine to Bisbenzotetracyclo[6.2.2.23,6 .02,7]tetradeca-4,9,11,13-tetraene.

    Science.gov (United States)

    Abbasoglu, Rza

    2010-12-01

    The mechanism and stereochemistry of electrophilic addition of chlorine to bisbenzotetracyclo[6.2.2.23,6.02,7]tetradeca-4,9,11,13-tetraene (BBTT) molecule were investigated by DFT methods. The geometry and the electronic structure of BBTT molecule was studied by DFT/B3LYP method using the 6-311G(d) and 6-311++G(d,p) basis sets. The double bonds of BBTT molecule are endo-pyramidalized. The structure and stability of the cationic intermediates and products of the addition reaction were investigated by B3LYP/6-311G(d) and B3LYP/6-311+G(2d,p) methods. The solvent effect was evaluated using SCI-PCM method. The bridged chloronium cation is isomerized into the more stable nonclassical delocalized N- and U-type cations, and the difference between the stability of these cations is small. For the determination of the direction of addition reaction and the stereochemistry of the products, the stability of nonclassical delocalized N- and U-type ions and the structure of their cationic centres play a vital role for the determination of the direction of addition reaction and the stereochemistry of the products. Since the cationic centre of the N-type ion is in interaction with the benzene ring from the exo face, the nucleophilic attack of the chloride anion to this centre occurs from the endo face, and the exo,endo-isomer of the N-type product is obtained. The attack of chloride anion towards the cationic centre of U-type ion from the endo face is sterically hindered by the hydrogen atom, therefore the attack occurs from the exo face, which interacts with the benzene ring and the more stable exo,exo-isomer of U-type product is formed. Although, the U-type cation was 3.485 kcal mol-1 more stable than the N-type cation, the U-type product was 1.886 kcal mol-1 [SCI-PCM-B3LYP/6-311++G(2d,p)// B3LYP/6-311G(d)] less stable than the N-type product.

  6. Tensor product model transformation based decoupled terminal sliding mode control

    Science.gov (United States)

    Zhao, Guoliang; Li, Hongxing; Song, Zhankui

    2016-06-01

    The main objective of this paper is to propose a tensor product model transformation based decoupled terminal sliding mode controller design methodology. The methodology is divided into two steps. In the first step, tensor product model transformation is applied to the single-input-multi-output system and a parameter-varying weighted linear time-invariant system is obtained. Then, decoupled terminal sliding mode controller is designed based on the linear time-invariant systems. The main novelty of this paper is that the nonsingular terminal sliding mode control design is based on a numerical model rather than an analytical one. Finally, simulations are tested on cart-pole system and translational oscillations with a rotational actuator system.

  7. A socio-technical approach for the design of a production control system : towards controllable production units

    NARCIS (Netherlands)

    Slomp, Jannes; Ruël, Gwenny C.

    2000-01-01

    In the design of a production control system much attention is usually paid to technicalaspects, whereas the elaboration upon social aspects remain underexposed. SociotechnicalSystems Theory (SST) emphasizes the importance of finding a joint optimization between the technical and the social systems

  8. Inversion of the Side-Chain Stereochemistry of Indvidual Thr or Ile Residues in a Protein Molecule: Impact on the Folding, Stability, and Structure of the ShK Toxin.

    Science.gov (United States)

    Dang, Bobo; Shen, Rong; Kubota, Tomoya; Mandal, Kalyaneswar; Bezanilla, Francisco; Roux, Benoit; Kent, Stephen B H

    2017-03-13

    ShK toxin is a cysteine-rich 35-residue protein ion-channel ligand isolated from the sea anemone Stichodactyla helianthus. In this work, we studied the effect of inverting the side chain stereochemistry of individual Thr or Ile residues on the properties of the ShK protein. Molecular dynamics simulations were used to calculate the free energy cost of inverting the side-chain stereochemistry of individual Thr or Ile residues. Guided by the computational results, we used chemical protein synthesis to prepare three ShK polypeptide chain analogues, each containing either an allo-Thr or an allo-Ile residue. The three allo-Thr or allo-Ile-containing ShK polypeptides were able to fold into defined protein products, but with different folding propensities. Their relative thermal stabilities were measured and were consistent with the MD simulation data. Structures of the three ShK analogue proteins were determined by quasi-racemic X-ray crystallography and were similar to wild-type ShK. All three ShK analogues retained ion-channel blocking activity.

  9. Alkene selenenylation: A comprehensive analysis of relative reactivities, stereochemistry and asymmetric induction, and their comparisons with sulfenylation

    Directory of Open Access Journals (Sweden)

    Donna J. Nelson

    2011-06-01

    Full Text Available A broad perspective of various factors influencing alkene selenenylation has been developed by concurrent detailed analysis of key experimental and theoretical data, such as asymmetric induction, stereochemistry, relative reactivities, and comparison with that of alkene sulfenylation. Alkyl group branching α to the double bond was shown to have the greatest effect on alkene reactivity and the stereochemical outcome of corresponding addition reactions. This is in sharp contrast with other additions to alkenes, which depend more on the degree of substitution on C=C or upon substituent electronic effects. Electronic and steric effects influencing asymmetric induction, stereochemistry, regiochemistry, and relative reactivities in the addition of PhSeOTf to alkenes are compared and contrasted with those of PhSCl.

  10. Cohaerins G-K, azaphilone pigments from Annulohypoxylon cohaerens and absolute stereochemistry of cohaerins C-K.

    Science.gov (United States)

    Surup, Frank; Mohr, Kathrin I; Jansen, Rolf; Stadler, Marc

    2013-11-01

    Four azaphilones, for which the trivial names cohaerins G, H, I and K are proposed, were isolated from the methanolic stromatal extract of Annulohypoxylon cohaerens together with the known metabolites cohaerins C-F and 4,5,4',5'-tetrahydroxy-1,1'-binaphthyl (BNT). Their planar structures were determined by NMR spectroscopy and by mass spectrometry. While their core structure is identical with cohaerin C and F, respectively, subgroups 2-hydroxy-6-methylphenyl and (1R,2R,4S)-4-hydroxy-2-methyl-6-oxocyclohexyl account for the structural diversity as substituents at C-3 of the azaphilone core. The absolute stereochemistry was assigned by NOE NMR experiments, CD spectroscopy and derivatisation with Mosher's acid; in addition, the stereochemistry of cohaerins C-F was revised. The metabolites showed cytotoxic effects besides a weak antimicrobial activity.

  11. Lactate dehydrogenase has no control on lactate production but has a strong negative control on formate production in Lactococcus lactis

    DEFF Research Database (Denmark)

    Andersen, H.W.; Pedersen, M.B.; Hammer, Karin

    2001-01-01

    A series of mutant strains of Lactococcus lactis were constructed with lactate dehydrogenase (LDH) activities ranging from below 1% to 133% of the wild-type activity level. The mutants with 59% to 133% of lactate dehydrogenase activity had growth rates similar to the wild-type and showed...... a homolactic pattern of fermentation. Only after lactate dehydrogenase activity was reduced ninefold compared to the wild-type was the growth rate significantly affected, and the ldh mutants started to produce mixed-acid products (formate, acetate, and ethanol in addition to lactate). Flux control coefficients...... were determined and it was found that lactate dehydrogenase exerted virtually no control on the glycolytic flux at the wild-type enzyme level and also not on the flux catalyzed by the enzyme itself, i.e. on the lactate production. As expected, the flux towards the mixed-acid products was strongly...

  12. Application of the suggestion system in the improvement of the production process and product quality control

    Science.gov (United States)

    Gołaś, H.; Mazur, A.; Gruszka, J.; Szafer, P.

    2016-08-01

    The elaboration is a case study and the research was carried out in the company Alco-Mot Ltd., which employs 120 people. The company specializes in the production of lead poles for industrial and traction batteries using gravity casting. The elements embedded in the cast are manufactured on a machining centre, which provides the stability of the process and of the dimensions of the product as well as a very short production time. As a result of observation and analysis the authors have developed a concept for the implementation of a dynamic suggestion system in ALCO-MOT, including, among others, a standard for actions in the implementation of the suggestion system, as well as clear guidelines for the processing and presentation of the activities undertaken in the time between the establishment of the concept (suggestions) and the benefits analysis after the proposed solutions have been implemented. The authors also present how suggestions proposed by ALCO-MOT staff contributed to the improvement of the processes of production and quality control. Employees offered more than 30 suggestions, of which more than a half are being implemented now and further actions are being prepared for implementation. The authors will present the results of improvements in, for example, tool replacement time, scrap reduction. The authors will present how kaizen can improve the production and quality control processes. They will present how the production and quality control processes looked before and after the implementation of employee suggestions.

  13. Implementation of hazard analysis critical control point in jameed production.

    Science.gov (United States)

    Al-Saed, A K; Al-Groum, R M; Al-Dabbas, M M

    2012-06-01

    The average of standard plate count and coliforms, Staphylococcus aureus and Salmonella counts for three home-made jameed samples, a traditional fermented dairy product, before applying hazard analysis critical control point system were 2.1 × 10(3), 8.9 × 10(1), 4 × 10(1) and less than 10 cfu/g, respectively. The developed hazard analysis critical control point plan resulted in identifying ten critical control points in the flow chart of jameed production. The critical control points included fresh milk receiving, pasteurization, addition of starter, water and salt, straining, personnel hygiene, drying and packaging. After applying hazard analysis critical control point system, there was significant improvement in the microbiological quality of the home-made jameed. The standard plate count was reduced to 3.1 × 10(2) cfu/g whereas coliform and Staphylococcus aureus counts were less than 10 cfu/g and Salmonella was not detected. Sensory evaluation results of color and flavor of sauce prepared from jameed showed a significant increase in the average scores given after hazard analysis critical control point application.

  14. Radiological control of food importation products; Control radiologico de productos alimenticios de importacion

    Energy Technology Data Exchange (ETDEWEB)

    Aguirre G, J. [CNSNS, Dr. Barragan 779, 03020 Mexico D.F. (Mexico)]. e-mail: jaguirre@cnsns.gob.mx

    2003-07-01

    Nowadays exists the possibility of marketing products possibly polluted with radioactive isotopes, by that some countries like Mexico, they have been given to the task of creating legal bases and the necessary infrastructure with the end of carrying out the radiological surveillance of nutritious import products. In this work the legal bases that our country has established for the radiological control are presented besides the results of this radiological control carried out through the gamma spectroscopy analysis of nutritious import products sent to our country through diverse companies that import foods produced mainly in European countries. (Author)

  15. Ecosystem and physiological controls over methane production in northern wetlands

    Science.gov (United States)

    Valentine, David W.; Holland, Elisabeth A.; Schimel, David S.

    1994-01-01

    Peat chemistry appears to exert primary control over methane production rates in the Canadian Northern Wetlands Study (NOWES) area. We determined laboratory methane production rate potentials in anaerobic slurries of samples collected from a transect of sites through the NOWES study area. We related methane production rates to indicators of resistance to microbial decay (peat C: N and lignin: N ratios) and experimentally manipulated substrate availability for methanogenesis using ethanol (EtOH) and plant litter. We also determined responses of methane production to pH and temperature. Methane production potentials declined along the gradient of sites from high rates in the coastal fens to low rates in the interior bogs and were generally highest in surface layers. Strong relationships between CH4 production potentials and peat chemistry suggested that methanogenesis was limited by fermentation rates. Methane production at ambient pH responded strongly to substrate additions in the circumneutral fens with narrow lignin: N and C: N ratios (delta CH4/delta EtOH = 0.9-2.3 mg/g) and weakly in the acidic bogs with wide C: N and lignin: N ratios (delta CH4/delta EtOH = -0.04-0.02 mg/g). Observed Q(sub 10) values ranged from 1.7 to 4.7 and generally increased with increasing substrate availability, suggesting that fermentation rates were limiting. Titration experiments generally demonstrated inhibition of methanogenesis by low pH. Our results suggest that the low rates of methane emission observed in interior bogs during NOWES likely resulted from pH and substrate quality limitation of the fermentation step in methane production and thus reflect intrinsically low methane production potentials. Low methane emission rates observed during NOWES will likely be observed in other northern wetland regions with similar vegetation chemistry.

  16. Trends in microbial control techniques for poultry products.

    Science.gov (United States)

    Silva, Filomena; Domingues, Fernanda C; Nerín, Cristina

    2016-07-20

    Fresh poultry meat and poultry products are highly perishable foods and high potential sources of human infection due to the presence of several foodborne pathogens. Focusing on the microbial control of poultry products, the food industry generally implements numerous preventive measures based on the Hazard Analysis and Critical Control Points (HACCP) food safety management system certification together with technological steps, such as refrigeration coupled to modified atmosphere packaging that are able to control identified potential microbial hazards during food processing. However, in recent years, to meet the demand of consumers for minimally processed, high-quality, and additive-free foods, technologies are emerging associated with nonthermal microbial inactivation, such as high hydrostatic pressure, irradiation, and natural alternatives, such as biopreservation or the incorporation of natural preservatives in packaging materials. These technologies are discussed throughout this article, emphasizing their pros and cons regarding the control of poultry microbiota and their effects on poultry sensory properties. The discussion for each of the preservation techniques mentioned will be provided with as much detail as the data and studies provided in the literature for poultry meat and products allow. These new approaches, on their own, have proved to be effective against a wide range of microorganisms in poultry meat. However, since some of these emergent technologies still do not have full consumer's acceptability and, taking into consideration the hurdle technology concept for poultry processing, it is suggested that they will be used as combined treatments or, more frequently, in combination with modified atmosphere packaging.

  17. Positron plasma control techniques for the production of cold antihydrogen

    Science.gov (United States)

    Funakoshi, R.; Amoretti, M.; Bonomi, G.; Bowe, P. D.; Canali, C.; Carraro, C.; Cesar, C. L.; Charlton, M.; Doser, M.; Fontana, A.; Fujiwara, M. C.; Genova, P.; Hangst, J. S.; Hayano, R. S.; Jørgensen, L. V.; Kellerbauer, A.; Lagomarsino, V.; Landua, R.; Lodi Rizzini, E.; Macrì, M.; Madsen, N.; Manuzio, G.; Mitchard, D.; Montagna, P.; Posada, L. G. C.; Rotondi, A.; Testera, G.; Variola, A.; Venturelli, L.; van der Werf, D. P.; Yamazaki, Y.; Zurlo, N.

    2007-07-01

    An observation of a clear dependence of antihydrogen production on positron plasma shapes is reported. For this purpose a plasma control method has been developed combining the plasma rotating-wall technique with a mode diagnostic system. With the help of real-time and nondestructive observations, the rotating-wall parameters have been optimized. The positron plasma can be manipulated into a wide range of shapes (aspect ratio 6.5⩽α≲80 ) and densities (1.5×108⩽n≲7×109cm-3) within a short duration (25s) compatible with the ATHENA antihydrogen production cycle.

  18. Positron plasma control techniques for the production of cold antihydrogen

    CERN Document Server

    Funakoshi, R; Bonomi, G; Bowe, P D; Canali, C; Carraro, C; Cesar, C L; Charlton, M; Doser, M; Fontana, A; Fujiwara, M C; Genova, P; Hangst, J S; Hayano, R S; Jørgensen, L V; Kellerbauer, A G; Lagomarsino, V; Landua, R; Lodi-Rizzini, E; Macrì, M; Madsen, N; Manuzio, G; Mitchard, D; Montagna, P; Posada, L G C; Rotondi, A; Testera, G; Variola, A; Venturelli, L; Van der Werf, D P; Yamazaki, Y; Zurlo, N

    2007-01-01

    An observation of a clear dependence of antihydrogen production on positron plasma shapes is reported. For this purpose a plasma control method has been developed combining the plasma rotating-wall technique with a mode diagnostic system. With the help of real-time and nondestructive observations, the rotating-wall parameters have been optimized. The positron plasma can be manipulated into a wide range of shapes (aspect ratio 6.5≤α≲80) and densities (1.5×108≤n≲7×109 cm−3) within a short duration (25 s) compatible with the ATHENA antihydrogen production cycle.

  19. Method for ph-controlled fermentation and biogas production

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention is in the field of biomass processing and bioenergy production and facilitates efficient biomass processing and an increased production of renewable energy from processing and anaerobic fermentation of a wide variety of organic materials. In order to control the pH value of ...... of the biomass during processing thereof, a CO 2 containing gas, such as e.g. biogas or flue gas, is added to the biomass present in the buffer tank and/or in the anaerobic digester operably linked to the buffer tank...

  20. Asymmetric synthesis and absolute stereochemistry of a labdane-type diterpenoid isolated from the rhizomes of Isodan yuennanensis.

    Science.gov (United States)

    Deng, Heping; Cao, Wei; Zhang, Zhijiang; Liu, Bo

    2016-07-14

    The first synthesis of a labdane-type diterpenoid isolated from Isodon yuennanensis was achieved in fourteen steps from commercially available starting material, (+)-sclareolide. The synthesis features the Barton nitrite ester reaction to introduce an oxime at the angular methyl group and the Jones oxidation to construct the lactone segment. By comparison of the optical rotation of our synthetic sample and the natural sample, the absolute stereochemistry of the natural diterpenoid has been determined.

  1. INVENTORY CONTROL OF A MULTIPRODUCT SYSTEM WITH A LIMITED PRODUCTION RESOURCE,

    Science.gov (United States)

    INVENTORY CONTROL , MANAGEMENT ENGINEERING), (*MANAGEMENT ENGINEERING, INDUSTRIAL PRODUCTION), (*MANAGEMENT PLANNING AND CONTROL, MATHEMATICAL MODELS), OPERATIONS RESEARCH, DYNAMIC PROGRAMMING, COSTS, EQUATIONS

  2. Tensor Product Model Transformation Based Adaptive Integral-Sliding Mode Controller: Equivalent Control Method

    Directory of Open Access Journals (Sweden)

    Guoliang Zhao

    2013-01-01

    Full Text Available This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model.

  3. Tensor product model transformation based adaptive integral-sliding mode controller: equivalent control method.

    Science.gov (United States)

    Zhao, Guoliang; Sun, Kaibiao; Li, Hongxing

    2013-01-01

    This paper proposes new methodologies for the design of adaptive integral-sliding mode control. A tensor product model transformation based adaptive integral-sliding mode control law with respect to uncertainties and perturbations is studied, while upper bounds on the perturbations and uncertainties are assumed to be unknown. The advantage of proposed controllers consists in having a dynamical adaptive control gain to establish a sliding mode right at the beginning of the process. Gain dynamics ensure a reasonable adaptive gain with respect to the uncertainties. Finally, efficacy of the proposed controller is verified by simulations on an uncertain nonlinear system model.

  4. Product State Models in Holonic shop floor control systems

    DEFF Research Database (Denmark)

    Langer, Gilad; Sørensen, Christian; Larsen, Michael Holm

    1999-01-01

    This paper reviews the concepts of the product state models as an integrated database for Holonic Shop Floor Control. One of the requirements of agility is to be able to realise real-time control of manufacturing systems based on the actual state of the system and especially the state of its...... this as well as the general concepts of the PSM and the important parts of the HoMuCS system architecture. Finally the integration of a PSM is illustrated in a case study based on an industrial case at the Odense Steel Shipyard Ltd....

  5. Shoreline as a controlling factor in commercial shrimp production

    Science.gov (United States)

    Faller, K. H. (Principal Investigator)

    1979-01-01

    The author has identified the following significant results. An ecological model was developed that relates marsh detritus export and shrimp production. It was based on the hypothesis that the shoreline is a controlling factor in the production of shrimp through regulation of detritus export from the marsh. LANDSAT data were used to develop measurement of shoreline length and areas of marsh having more than 5.0 kilometers of shoreline per square kilometer of area for the Louisiana coast, demonstrating the capability of remote sensing to provide important geographic information. These factors were combined with published tidal ranges and salinities to develop a mathematical model that predicted shrimp production for nine geographic units of the Louisiana coast, as indicated by the long term average commercial shrimp yield.

  6. Design requirements for SRB production control system. Volume 4: Implementation

    Science.gov (United States)

    1981-01-01

    The implementation plan which is presented was developed to provide the means for the successful implementation of the automated production control system. There are three factors which the implementation plan encompasses: detailed planning; phased implementation; and user involvement. The plan is detailed to the task level in terms of necessary activities as the system is developed, refined, installed, and tested. These tasks are scheduled, on a preliminary basis, over a two-and-one-half-year time frame.

  7. Robust control charts in industrial production of olive oil

    Science.gov (United States)

    Grilo, Luís M.; Mateus, Dina M. R.; Alves, Ana C.; Grilo, Helena L.

    2014-10-01

    Acidity is one of the most important variables in the quality analysis and characterization of olive oil. During the industrial production we use individuals and moving range charts to monitor this variable, which is not always normal distributed. After a brief exploratory data analysis, where we use the bootstrap method, we construct control charts, before and after a Box-Cox transformation, and compare their robustness and performance.

  8. Electronic Nose for Microbiological Quality Control of Food Products

    OpenAIRE

    Falasconi, M.; I. Concina; E. Gobbi; Sberveglieri, V.; A. Pulvirenti; G. Sberveglieri

    2012-01-01

    Electronic noses (ENs) have recently emerged as valuable candidates in various areas of food quality control and traceability, including microbial contamination diagnosis. In this paper, the EN technology for microbiological screening of food products is reviewed. Four paradigmatic and diverse case studies are presented: (a) Alicyclobacillus spp. spoilage of fruit juices, (b) early detection of microbial contamination in processed tomatoes, (c) screening of fungal and fumonisin contamination ...

  9. Optimal Control Approaches to the Aggregate Production Planning Problem

    Directory of Open Access Journals (Sweden)

    Yasser A. Davizón

    2015-12-01

    Full Text Available In the area of production planning and control, the aggregate production planning (APP problem represents a great challenge for decision makers in production-inventory systems. Tradeoff between inventory-capacity is known as the APP problem. To address it, static and dynamic models have been proposed, which in general have several shortcomings. It is the premise of this paper that the main drawback of these proposals is, that they do not take into account the dynamic nature of the APP. For this reason, we propose the use of an Optimal Control (OC formulation via the approach of energy-based and Hamiltonian-present value. The main contribution of this paper is the mathematical model which integrates a second order dynamical system coupled with a first order system, incorporating production rate, inventory level, and capacity as well with the associated cost by work force in the same formulation. Also, a novel result in relation with the Hamiltonian-present value in the OC formulation is that it reduces the inventory level compared with the pure energy based approach for APP. A set of simulations are provided which verifies the theoretical contribution of this work.

  10. RECONFIGURABLE PRODUCT ROUTING AND CONTROL FOR MASS CUSTOMISATION MANUFACTURING

    Directory of Open Access Journals (Sweden)

    A. J. Walker

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT:Reconfigurable control of flexible manufacturing systems can allow for the efficient and responsive production of customised product instances. This can aid in providing make-to-order business models for various small- to medium-sized enterprises in South Africa, and provide competitive advantage in a dynamic global marketplace. Reconfigurable control application requires an understanding of the modes of production variability in mass customisation manufacturing. Temporally uncorrelated workflow routings are considered as one of these production variability modes. In this light, this paper addresses the flexible material payload routing problem, and presents a mobile robot platform that has been developed to research and design reconfigurable routing systems.

    AFRIKAANSE OPSOMMING:Verstelbare beheer van aanpasbare vervaardigingstelsels kan die doeltreffende en reaktiewe produksie van doelgemaakte produkeksemplare toelaat. Hierdie beheer kan assisteer in die voorsiening van vervaardig-na-bestellingbesigheidsmodelle aan ’n aantal klein- tot medium-grootte ondernemings in Suid-Afrika, en aan hulle ’n kompeterende voorsprong bied in ’n dinamiese globale mark. Die instelling van verstelbare beheer vereis dat die modi van produkveranderlikheid in massa verbruikersaanpassingsvervaardiging verstaan word. Hierdie artikel spreek die probleem van aanpasbare roetebepaling van materiaalvragte in massa verbruikersaanpassingsvervaardiging aan. ’n Mobiele robot-platform, ontwikkel vir navorsing in verstelbare roetebepalingstelsels, word ook voorgelê.

  11. Glycosylation: impact, control and improvement during therapeutic protein production.

    Science.gov (United States)

    Costa, Ana Rita; Rodrigues, Maria Elisa; Henriques, Mariana; Oliveira, Rosário; Azeredo, Joana

    2014-12-01

    The emergence of the biopharmaceutical industry represented a major revolution for modern medicine, through the development of recombinant therapeutic proteins that brought new hope for many patients with previously untreatable diseases. There is a ever-growing demand for these therapeutics that forces a constant technological evolution to increase product yields while simultaneously reducing costs. However, the process changes made for this purpose may also affect the quality of the product, a factor that was initially overlooked but which is now a major focus of concern. Of the many properties determining product quality, glycosylation is regarded as one of the most important, influencing, for example, the biological activity, serum half-life and immunogenicity of the protein. Consequently, monitoring and control of glycosylation is now critical in biopharmaceutical manufacturing and a requirement of regulatory agencies. A rapid evolution is being observed in this context, concerning the influence of glycosylation in the efficacy of different therapeutic proteins, the impact on glycosylation of a diversity of parameters/processes involved in therapeutic protein production, the analytical methodologies employed for glycosylation monitoring and control, as well as strategies that are being explored to use this property to improve therapeutic protein efficacy (glycoengineering). This work reviews the main findings on these subjects, providing an up-to-date source of information to support further studies.

  12. Prevalence of tabacco product use in Latvia and control measures

    Directory of Open Access Journals (Sweden)

    Kokarevica A.

    2012-10-01

    Full Text Available The use of tobacco products is a major problem having a serious effect on public health. Deaths from external causes are those that can be prevented by ensuring environmental safety and educating the society about the effect of lifestyle habits and behaviour on health of an individual. Not only research data reveal the prevalence of tobacco use but also the rate of tobacco sales. Tobacco industry marketing includes advertising, sales promotion and sponsorship strategies that are aimed at promotion of tobacco use. Demand for tobacco products is influenced also by changes in legislation relating to ban on tobacco advertising and sponsorship. Therefore it is necessary to introduce an agreed strategy for reducing tobacco use. The countries that have ratified the World Health Organisation (WHO Framework Convention on Tobacco Control (the Convention should develop and implement an effective tobacco control programme. In Latvia the number of daily smokers gradually decreases thanks to the extensive smoking restrictions though tobacco manufacturers use all the available media, radio and television, newspapers, magazines, advertisements and Internet, to advertise their products. Therefore in order to combat the prevalence of smoking first of all it is necessary to limit cigarette marketing and sales and to carry out monitoring and development of tobacco control measures on the state level. The sales of legal cigarettes have decreased in Latvia starting from 2009. However, the increase in tax rates and prices has contributed to the movement of illegal goods therefore it is necessary to take additional restrictive measures concerning the movement of illegal goods. Though amendments to legislation of Latvia relating to tobacco control comply with the requirements of the WHO Convention it is necessary to evaluate the efficiency of control measures and to improve them. Systematic and comprehensive education of the public is required to encourage the change of

  13. 21 CFR 212.50 - What production and process controls must I have?

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false What production and process controls must I have... DRUGS (Eff. 12-12-2011) Production and Process Controls § 212.50 What production and process controls must I have? You must have adequate production and process controls to ensure the consistent...

  14. Visualization and Quality Control Web Tools for CERES Products

    Science.gov (United States)

    Mitrescu, C.; Doelling, D.; Chu, C.; Mlynczak, P.

    2014-12-01

    The CERES project continues to provide the scientific community a wide variety of satellite-derived data products. The flagship products TOA broadband shortwave and longwave observed fluxes, computed TOA and Surface fluxes, as well as cloud, aerosol, and other atmospheric parameters. These datasets encompass a wide range of temporal and spatial resolutions, suited to specific applications. We thus offer time resolutions that range from instantaneous to monthly means, with spatial resolutions that range from 20-km footprint to global scales. The 14-year record is mostly used by climate modeling communities that focus on global mean energetics, meridianal heat transport, and climate trend studies. CERES products are also used by the remote sensing community for their climatological studies. In the last years however, our CERES products had been used by an even broader audience, like the green energy, health and environmental research communities, and others. Because of that, the CERES project has implemented a now well-established web-oriented Ordering and Visualization Tool (OVT), which is well into its fifth year of development. In order to help facilitate a comprehensive quality control of CERES products, the OVT Team began introducing a series of specialized functions. These include the 1- and 2-D histogram, anomaly, deseasonalization, temporal and spatial averaging, side-by-side parameter comparison, and other specialized scientific application capabilities. Over time increasingly higher order temporal and spatial resolution products are being made available to the public through the CERES OVT. These high-resolution products require accessing the existing long-term archive - thus the reading of many very large netCDF or HDF files that pose a real challenge to the task of near instantaneous visualization. An overview of the CERES OVT basic functions and QC capabilities as well as future steps in expanding its capabilities will be presented at the meeting.

  15. Methods for the comprehensive structural elucidation of constitution and stereochemistry of lipopeptides.

    Science.gov (United States)

    Gerhardt, Heike; Sievers-Engler, Adrian; Jahanshah, Ghazaleh; Pataj, Zoltán; Ianni, Federica; Gross, Harald; Lindner, Wolfgang; Lämmerhofer, Michael

    2016-01-08

    A panel of methods of general suitability for complete structural elucidation of the stereochemistry of cyclopeptides, depsipeptides and lipopeptides is presented and described in detail. The suitability of the proposed methods was exemplified on the lipopeptide poaeamide from Pseudomonas poae. Amino acid configurations have been assigned by direct LC enantiomer separation with Chiralpak ZWIX(+) and were confirmed by GC enantiomer separation on Chirasil L-Val. 3-Hydroxydecanoic acid absolute configuration was analyzed on Chiralpak ZWIX(+) and confirmed by injection on ZWIX(-) which showed opposite elution order. Plenty of d-amino acids have been found in this lipopeptide. It contained in total 5 Leu residues of which one had d-configuration. The position of the d-Leu in the peptide sequence was determined by pepsin and chemical digestions in combination with isolation of diagnostic peptide-fragments and subsequent identification of absolute configurations of the Leu residues. This allowed pinpointing the position of the d-amino acid. The complementarity of the peptide retention profiles on Chiralpak ZWIX column as compared to both RPLC and HILIC suggests its great utility as an alternative peptide separation tool.

  16. Absolute Stereochemistry of the β-Hydroxy Acid Unit in Hantupeptins and Trungapeptins.

    Science.gov (United States)

    Gupta, Deepak Kumar; Ding, Gary Chi Ying; Teo, Yong Chua; Tan, Lik Tong

    2016-01-01

    The β-hydroxy/amino acid unit is a common structural feature of many bioactive marine cyanobacterial depsipeptides. In this study, the absolute stereochemistry of the β-hydroxy acid moieties in hantupeptins and trungapeptins were determined through their synthesis and HPLC analysis of the Mosher ester derivatives. Synthesis of two3-hydroxy-2-methyloctanoic acid (Hmoa) stereoisomers, (2S,3R)-Hmoa and (2S,3S)-Hmoa, were achieved using diastereoselective asymmetric method and the retention times of all four Hmoa isomers were established indirectly by RPLC-MS analysis of their Mosher ester derivative standards. Based on the retention times of the standards, the absolute configuration of the Hmoa unit in hantupeptin C (3) and trungapeptin C (6) was assigned as (2R,3S)- and (2S,3R)-Hmoa, respectively. The use of the Mosher's reagents, coupled with HPLC analysis, provided a viable alternative to the absolute stereochemical determination of β-hydroxy acid units in depsipeptides.

  17. Isolation of brassicasterol, its synthetic prodrug-crystal structure, stereochemistry and theoretical studies

    Science.gov (United States)

    Sethi, Arun; Prakash, Rohit; Srivastava, Sangeeta; Amandeep; Bishnoi, Abha; Singh, Ranvijay Pratap

    2014-07-01

    In the present study brassicasterol (1), was isolated from the chloroform extract of the flowers of Allamanda violacea and identified with the help of different spectroscopic techniques like 1H, 13C, 2D NMR (1H-1H COSY), IR, UV and mass spectrometry. A novel prodrug was synthesized by carrying out esterification of brassicasterol (1) with the well known drug naproxen using Steglich esterification to give 3β-(2-(6-methoxynaphthalene-2yl) propionoxy) 24 methyl cholest-5, 22-dien (2). Compounds 2 was subjected to single crystal X-ray diffraction technique and crystallized out in monoclinic form having P21 space group and stabilized by CH-π interactions. Structure and stereochemistry of compound 2 was established with the help of modern spectroscopic techniques like 1H NMR, IR, UV, mass spectrometry as well as with single crystal X-ray diffraction. Molecular geometry and vibrational frequencies of compounds 1 and 2 were calculated by density functional method (DFT/B3LYP) using 6-31G (d, p) basis set, bond parameters and IR frequencies were correlated with the experimental data. 1H and 13C chemical shifts of compound 1 and 1H chemical shifts of compound 2 were calculated with GIAO method and correlated with experimental data. Hyperconjugative interactions were studied with the help of natural bond order analysis (NBO). Electronic properties of both the compounds such as HOMO-LUMO energies were measured with the help of time dependent DFT method.

  18. Temperature-dependent annuloselectivity and stereochemistry in the reactions of methanesulfonyl sulfene with imines.

    Science.gov (United States)

    Wu, Qiuyue; Yang, Zhanhui; Xu, Jiaxi

    2016-07-26

    The annuloselectivity in the reactions of methanesulfonyl sulfene and imines varies with temperature. At a relatively higher temperature of 20 °C, the [2(s) + 2(i)] annulation of different N-alkyl imines occurs exclusively, giving four-membered trans-β-sultams in up to 69% yields. At a lower temperature of -78 °C, the [2(s) + 2(i) + 2(i)] annulation of N-methyl imines takes place specifically, delivering six-membered 1,2,4-thiadiazine 1,1-dioxides, 4-aza-δ-sultams, in up to 80% yields, with diverse configurations at the C3, C5, and C6 stereocenters. The trans-stereochemistry involved in the [2(s) + 2(i)] annulations is attributed to the conrotatory ring closure of the thermodynamically stable 2,3-thiazabutadiene-type zwitterionic intermediates, while the diverse stereochemical outcomes in the [2(s) + 2(i) + 2(i)] annulations are caused by the iminium isomerization in the stepwise nucleophilic [4 + 2] annulation between the same zwitterionic intermediates and a second molecule of N-methyl imines.

  19. Looking for treasure in stereochemistry-land. A path marked by curiosity, obstinacy, and serendipity.

    Science.gov (United States)

    Juaristi, Eusebio

    2012-06-01

    Over the past 40 years, much of my research has evolved around various topics of conformational analysis and asymmetric synthesis. This Perspective describes some of my salient contributions in eight different areas of organic stereochemistry: (1) conformational analysis of six-membered rings, (2) evaluation of stereoelectronic interactions in (1)J(C-H) one-bond coupling constants in six-membered rings, (3) eclipsed conformation in cis-2-tert-butyl-5-(tert-butylsulfonyl)-1,3-dioxane, (4) determination of enthalpic and entropic contributions to ΔG°(CH(2)Ph) and ΔG°(t-Bu), (5) study of the "attractive gauche effect" in O-C-C-O segments, (6) examination of salt effects on conformational equilibria, (7) asymmetric synthesis of β-amino acids, and (8) asymmetric organocatalysis and "Green" chemistry. It will be appreciated that a basic understanding of the principles of physical organic chemistry has been essential in all projects. Furthermore, curiosity, enthusiasm, obstinacy, and paying attention to unexpected observations will lead to many new (stereo)chemical discoveries.

  20. Control of corrosion in oil and gas production tubing

    Energy Technology Data Exchange (ETDEWEB)

    Smith, L. [Intetech Ltd., Chester (United Kingdom)

    1999-07-01

    Controlling corrosion in production tubing is essential for maintaining production and for preventing loss of well control. Materials for use downhole have to meet criteria for corrosion resistance and also mechanical requirements. The potential corrosion rate can be estimated and the risks of sulphide stress corrosion cracking assessed on the basis of the anticipated environmental conditions and flow regime. Material options for tubing can then be considered on the basis of published corrosion test data and also field experience. Candidate materials may be tested and the precise field conditions expected in order to ensure that overconservative choices are not made. Corrosion inhibitors, coated carbon steel, and fibre reinforced plastic tubing have temperature, flow regime, and mechanical limitations. Specific corrosion resistant alloys (CRAs) have environmental limitations with respect to temperature, hydrogen sulphide, and chloride content. Details of field experience with all of these material options are given. There exists a large amount of experience with CRAs for downhole applications. Correctly selected CRAs have a good track record of service, even for hostile, H{sub 2}S containing conditions. There are a few limited examples of CRA clad tubing. This product may be one that needs re-evaluation as it offers potential for economic use of costly but effective CRAs. (Author)

  1. Production control and supplier selection under demand disruptions

    Directory of Open Access Journals (Sweden)

    Xianzhe Chen

    2010-12-01

    Full Text Available This paper investigates the effects of demand disruptions on production control and supplier selection in a three-echelon supply chain system. The customer demand is modeled as a jump-diffusion process in a continuous-time setting. A two-number production-inventory policy is implemented in the production control model for the manufacturer. The objective is to minimize the long-term average total cost consisting of backlog cost, holding cost, switching cost, and ordering cost. The simulated annealing method is applied to search the optimal critical switching values. Furthermore, an improved analytical hierarchy process (AHP is proposed to select the best supplier, based on quantitative factors such as the optimal long-term total cost obtained through the simulated annealing method under demand disruptions and qualitative factors such as quality and service. Numerical studies are conducted to demonstrate the effects of demand disruptions in the face of various risk scenarios. Managerial insights from simulation results are provided as well. Our approaches can be implemented as the “stress test” for companies in front of various supply chain disruption scenarios.

  2. Scientific and Quality Control Web Tools for CERES Products

    Science.gov (United States)

    Mitrescu, C.; Doelling, D.; Chu, C.

    2013-12-01

    CERES project provides the scientific community a wide variety of satellite-derived data products. These include TOA broadband shortwave, longwave observed fluxes, computed TOA and surface fluxes, as well as cloud, aerosol, and atmospheric parameters. The datasets encompass a wide range of temporal resolutions, from instantaneous to monthly means, and spatial resolution, from 20-km footprint to global means. The 13-year record is used in climate modeling communities that focus on global mean energetics, meridianal heat transport, and climate trend studies. The data is also used in the remote sensing community for climatological process studies. The CERES products have even attracted a broader audience, such as the green energy, health and environmental research communities. The CERES project has implemented a well-established web-based Ordering and Visualization Tool (OVT), which is well into its fourth year of development. In order to help facilitate the quality control of CERES data products, the OVT Team began introducing a series of specialized functions. These include the 1- and 2-D histogram, anomaly, deseasonalization, temporal averaging, user selected spatial domain time series, side-by-side parameter comparison, and other specialized scientific application capabilities. Over time increasingly higher order temporal and spatial resolution products are being made available to the public through the CERES OVT. These high-resolution products required accessing the long-term archive, and the reading of very large HDF files quickly to provide near instantaneous visualization. The CERES OVT is also modularizing the software to ensure scalability with the ever-increasing demands of expanding the science and analytical capabilities, the incorporation of data products and growing user activity, while maintaining reliability. An overview of the CERES OVT, highlights of the QC and scientific functions, and technical challenges that were overcome, will be presented at

  3. Use of Probiotics to Control Aflatoxin Production in Peanut Grains.

    Science.gov (United States)

    da Silva, Juliana Fonseca Moreira; Peluzio, Joenes Mucci; Prado, Guilherme; Madeira, Jovita Eugênia Gazzinelli Cruz; Silva, Marize Oliveira; de Morais, Paula Benevides; Rosa, Carlos Augusto; Pimenta, Raphael Sanzio; Nicoli, Jacques Robert

    2015-01-01

    Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20) were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1%) followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.). All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains.

  4. Use of Probiotics to Control Aflatoxin Production in Peanut Grains

    Science.gov (United States)

    da Silva, Juliana Fonseca Moreira; Peluzio, Joenes Mucci; Prado, Guilherme; Madeira, Jovita Eugênia Gazzinelli Cruz; Silva, Marize Oliveira; de Morais, Paula Benevides; Rosa, Carlos Augusto; Pimenta, Raphael Sanzio; Nicoli, Jacques Robert

    2015-01-01

    Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20) were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1%) followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.). All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains. PMID:26221629

  5. Use of Probiotics to Control Aflatoxin Production in Peanut Grains

    Directory of Open Access Journals (Sweden)

    Juliana Fonseca Moreira da Silva

    2015-01-01

    Full Text Available Probiotic microorganisms (Saccharomyces cerevisiae var. boulardii, S. cerevisiae UFMG 905, and Lactobacillus delbrueckii UFV H2b20 were evaluated as biological control agents to reduce aflatoxin and spore production by Aspergillus parasiticus IMI 242695 in peanut. Suspensions containing the probiotics alone or in combinations were tested by sprinkling on the grains followed by incubation for seven days at 25°C. All probiotic microorganisms, in live and inactivated forms, significantly reduced A. parasiticus sporulation, but the best results were obtained with live cells. The presence of probiotics also altered the color of A. parasiticus colonies but not the spore morphology. Reduction in aflatoxin production of 72.8 and 65.8% was observed for S. boulardii and S. cerevisiae, respectively, when inoculated alone. When inoculated in pairs, all probiotic combinations reduced significantly aflatoxin production, and the best reduction was obtained with S. boulardii plus L. delbrueckii (96.1% followed by S. boulardii plus S. cerevisiae and L. delbrueckii plus S. cerevisiae (71.1 and 66.7%, resp.. All probiotics remained viable in high numbers on the grains even after 300 days. The results of the present study suggest a different use of probiotics as an alternative treatment to prevent aflatoxin production in peanut grains.

  6. Control of temperature for health and productivity inoffices

    Energy Technology Data Exchange (ETDEWEB)

    Seppanen, Olli; Fisk, William J.; Faulkner, David

    2004-06-01

    Indoor temperature is one of the fundamental characteristics of the indoor environment. It can be controlled with different accuracy depending on the building and its HVAC system. The purpose of this study was to evaluate the potential benefits of improved temperature control, and apply the information for a cost-benefit analyses. The indoor temperature affects several human responses, including thermal comfort, perceived air quality, sick building syndrome symptoms and performance in work. In this study we focused on the effects of temperature on performance in work. We collected and analyzed the literature relating the performance in work and temperature. The results of multiple studies are relatively consistent and show an average relationship of 2% decrement in work performance per degree C when the temperature is above 25 C. Less data were available on the performance in low temperatures. However, studies show a strong effect on manual tasks with temperatures below thermal neutrality as soon as the temperature of hands decreased due to control of blood flow. When the estimated productivity decrement from elevated temperatures was applied to data from a study of night-time ventilative cooling, the estimated value of productivity improvements were 32 to 120 times greater than the cost of energy to run fans during the night.

  7. Soil Carbon Dioxide Production and Surface Fluxes: Subsurface Physical Controls

    Science.gov (United States)

    Risk, D.; Kellman, L.; Beltrami, H.

    Soil respiration is a critical determinant of landscape carbon balance. Variations in soil temperature and moisture patterns are important physical processes controlling soil respiration which need to be better understood. Relationships between soil respi- ration and physical controls are typically addressed using only surface flux data but other methods also exist which permit more rigorous interpretation of soil respira- tion processes. Here we use a combination of subsurface CO_{2} concentrations, surface CO_{2} fluxes and detailed physical monitoring of the subsurface envi- ronment to examine physical controls on soil CO_{2} production at four climate observatories in Eastern Canada. Results indicate that subsurface CO_{2} produc- tion is more strongly correlated to the subsurface thermal environment than the surface CO_{2} flux. Soil moisture was also found to have an important influence on sub- surface CO_{2} production, particularly in relation to the soil moisture - soil profile diffusivity relationship. Non-diffusive profile CO_{2} transport appears to be im- portant at these sites, resulting in a de-coupling of summertime surface fluxes from subsurface processes and violating assumptions that surface CO_{2} emissions are the result solely of diffusion. These results have implications for the study of soil respiration across a broad range of terrestrial environments.

  8. Control of temperature for health and productivity inoffices

    Energy Technology Data Exchange (ETDEWEB)

    Seppanen, Olli; Fisk, William J.; Faulkner, David

    2004-06-01

    Indoor temperature is one of the fundamental characteristics of the indoor environment. It can be controlled with different accuracy depending on the building and its HVAC system. The purpose of this study was to evaluate the potential benefits of improved temperature control, and apply the information for a cost-benefit analyses. The indoor temperature affects several human responses, including thermal comfort, perceived air quality, sick building syndrome symptoms and performance in work. In this study we focused on the effects of temperature on performance in work. We collected and analyzed the literature relating the performance in work and temperature. The results of multiple studies are relatively consistent and show an average relationship of 2% decrement in work performance per degree C when the temperature is above 25 C. Less data were available on the performance in low temperatures. However, studies show a strong effect on manual tasks with temperatures below thermal neutrality as soon as the temperature of hands decreased due to control of blood flow. When the estimated productivity decrement from elevated temperatures was applied to data from a study of night-time ventilative cooling, the estimated value of productivity improvements were 32 to 120 times greater than the cost of energy to run fans during the night.

  9. Biogas Production Modelling: A Control System Engineering Approach

    Science.gov (United States)

    Stollenwerk, D.; Rieke, C.; Dahmen, M.; Pieper, M.

    2016-03-01

    Due to the Renewable Energy Act, in Germany it is planned to increase the amount of renewable energy carriers up to 60%. One of the main problems is the fluctuating supply of wind and solar energy. Here biogas plants provide a solution, because a demand-driven supply is possible. Before running such a plant, it is necessary to simulate and optimize the process feeding strategy. Current simulation models are either very detailed like the ADM 1, which leads to very long optimization runtimes or not accurate enough to handle the biogas production kinetics. Therefore this paper provides a new model of a biogas plant, which is easy to parametrize but also has the needed accuracy for the output prediction. It is based on the control system approach of system identification and validated with laboratory results of a real biogas production testing facility.

  10. Implementation of Logic Flow in Planning and Production Control

    Directory of Open Access Journals (Sweden)

    Ulewicz Robert

    2016-03-01

    Full Text Available The article presents the results of analysis, the use of continuous flow of logic at the stage of production planning and control of the company producing furniture. The concept of continuous flow tends to regulate the flow of materials in a manner that provides the shortest flow path without unnecessary activities (Muda is a Japanese word meaning waste, a constant takt and defined throughput at constant resource requirements for the so-called transfer of material through the whole process. In the study Glenday’d sieve method was used to identify the correct area, which requires the value stream mapping, and areas called excessive complexity, which do not provide added value. The use of Glenday’s sieve method made it possible to identify areas in which it must be improve production capacity.

  11. Microbial control of hydrogen sulfide production in a porous medium

    Energy Technology Data Exchange (ETDEWEB)

    McInerney, M.J.; Wofford, N.Q. [Univ. of Oklahoma, Norman, OK (United States); Sublette, K.L. [Univ. of Tulsa, OK (United States)

    1996-12-31

    The ability of a sulfide- and glutaraldehyde-tolerant strain of Thiobacillus denitrificans (strain F) to control sulfide production in an experimental system of cores and formation water from the Redfield, Iowa natural gas storage facility was investigated. A stable, sulfide-producing biofilm was established in two separate core systems, one of which was inoculated with strain F, and the other core system (control) was treated in an identical manner, but was not inoculated with strain F. When formation water with 10 mM acetate and 5mM nitrate was injected into both core systems, the effluent sulfide concentrations in the control core system ranged from 200-460 {mu}M. In the test core system inoculated with strain F, the effluent sulfide concentrations were lower, ranging from 70-110 {mu}M. In order to determine whether strain F could control sulfide production under optimal conditions for sulfate-reducing bacteria, the electron donor was changed to lactate, and inorganic nutrients (nitrogen and phosphate sources) were added to the formation water. When nutrient-supplemented formation water with 3.1 mM lactate and 10 mM nitrate was used, the effluent sulfide concentrations of the control core system initially increased to about 3800 pM, and then decreased to about 1100 {mu}M after 5 wk. However, in the test core system inoculated with strain F, the effluent sulfide concentrations were much lower, 160-330 {mu}M. Nitrate consumption (5 mM) and high concentrations (101-1011 cells/mL) of strain F were detected in the test core system. An accumulation of biomass occurred in the influent lines during 2 mo of continuous operation, but only a small increase in injection pressure was observed. These studies showed that inoculation with strain F was needed for effective control of sulfide production, and that significant plugging or loss of injectivity owing to microbial inoculation did not occur. 7 refs., 3 figs., 1 tab.

  12. Neurons controlling Aplysia feeding inhibit themselves by continuous NO production.

    Directory of Open Access Journals (Sweden)

    Nimrod Miller

    Full Text Available BACKGROUND: Neural activity can be affected by nitric oxide (NO produced by spiking neurons. Can neural activity also be affected by NO produced in neurons in the absence of spiking? METHODOLOGY/PRINCIPAL FINDINGS: Applying an NO scavenger to quiescent Aplysia buccal ganglia initiated fictive feeding, indicating that NO production at rest inhibits feeding. The inhibition is in part via effects on neurons B31/B32, neurons initiating food consumption. Applying NO scavengers or nitric oxide synthase (NOS blockers to B31/B32 neurons cultured in isolation caused inactive neurons to depolarize and fire, indicating that B31/B32 produce NO tonically without action potentials, and tonic NO production contributes to the B31/B32 resting potentials. Guanylyl cyclase blockers also caused depolarization and firing, indicating that the cGMP second messenger cascade, presumably activated by the tonic presence of NO, contributes to the B31/B32 resting potential. Blocking NO while voltage-clamping revealed an inward leak current, indicating that NO prevents this current from depolarizing the neuron. Blocking nitrergic transmission had no effect on a number of other cultured, isolated neurons. However, treatment with NO blockers did excite cerebral ganglion neuron C-PR, a command-like neuron initiating food-finding behavior, both in situ, and when the neuron was cultured in isolation, indicating that this neuron also inhibits itself by producing NO at rest. CONCLUSION/SIGNIFICANCE: Self-inhibitory, tonic NO production is a novel mechanism for the modulation of neural activity. Localization of this mechanism to critical neurons in different ganglia controlling different aspects of a behavior provides a mechanism by which a humeral signal affecting background NO production, such as the NO precursor L-arginine, could control multiple aspects of the behavior.

  13. Indoor radon and decay products: Concentrations, causes, and control strategies

    Energy Technology Data Exchange (ETDEWEB)

    Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.

    1990-11-01

    This report is another in the on going technical report series that addresses various aspects of the DOE Radon Research Program. It provides an overview of what is known about the behavior of radon and its decay products in the indoor environment and examines the manner in which several important classes of factors -- structural, geological, and meteorological -- affect indoor radon concentrations. Information on US indoor radon concentrations, currently available monitoring methods and novel radon control strategies are also explored. 238 refs., 22 figs., 9 tabs.

  14. A performance comparison of single product kanban control systems

    Directory of Open Access Journals (Sweden)

    Alvin Ang

    2015-01-01

    Full Text Available This paper presents a simulation experiment comparing the Single Stage, Single Product Base Stock (BS, Traditional Kanban Control System (TKCS and Extended Kanban Control System (EKCS. The results showed that BS incurs the highest cost in all scenarios; while EKCS is found to be effective only in a very niche scenario. TKCS is still a very powerful factory management system to date; and EKCS did not perform exceptionally well. The only time EKCS did outperform TKCS was during low demand arrival rates and low Backorder (Cb and Shortage costs (Cs. That is because during then, it holds no stock. The most important discovery made here is that EKCS becomes TKCS once it has base stock (or dispatched kanbans. The results have also evinced the strength of the pure kanban system, the TKCS over BS. Hence managers using BS should consider upgrading to TKCS to save cost.

  15. Electronic Nose for Microbiological Quality Control of Food Products

    Directory of Open Access Journals (Sweden)

    M. Falasconi

    2012-01-01

    Full Text Available Electronic noses (ENs have recently emerged as valuable candidates in various areas of food quality control and traceability, including microbial contamination diagnosis. In this paper, the EN technology for microbiological screening of food products is reviewed. Four paradigmatic and diverse case studies are presented: (a Alicyclobacillus spp. spoilage of fruit juices, (b early detection of microbial contamination in processed tomatoes, (c screening of fungal and fumonisin contamination of maize grains, and (d fungal contamination on green coffee beans. Despite many successful results, the high intrinsic variability of food samples together with persisting limits of the sensor technology still impairs ENs trustful applications at the industrial scale. Both advantages and drawbacks of sensor technology in food quality control are discussed. Finally, recent trends and future directions are illustrated.

  16. Visualization and Quality Control Web Tools for CERES Products

    Science.gov (United States)

    Mitrescu, C.; Doelling, D.; Chu, C.; Rutan, D. A.

    2015-12-01

    The CERES project continues to provide the scientific community a wide variety of satellite-derived data products such as observed TOA broadband shortwave and longwave observed fluxes, computed TOA and Surface fluxes, as well as cloud, aerosol, and other atmospheric parameters. These datasets encompass a wide range of temporal and spatial resolutions, suited to specific applications. Now in its 15-year, CERES products are mostly used by climate modeling communities that focus on global mean energetics, meridianal heat transport, and climate trend studies. However, CERES products are now beginning to be used by an even broader audience, like the green energy, health and environmental agencies. With its well-established web-oriented Ordering and Visualization Tool (OVT), CERES products are now much more assessable to users of all communities. The OVT Team introduced a series of specialized functions such as 1- and 2-D histogram, anomaly, deseasonalization, temporal and spatial averaging, side-by-side parameter comparison, and others that made the process of Quality Control far easier and faster. Over time increasingly higher order temporal and spatial resolution products are being made available to the public through the CERES OVT's web-pages. Moreover, ground site observed surface fluxes are being integrated into the OVT to facilitate the CERES project to QC the CERES computed surface fluxes. These features will give users the opportunity to perform their own comparisons of the CERES computed surface fluxes and observed ground site fluxes. An overview of the CERES OVT basic functions and its QC capabilities, new developments, as well as future steps in expanding its capabilities will be presented at the meeting.

  17. Towards benchmarking of multivariable controllers in chemical/biochemical industries: Plantwide control for ethylene glycol production

    DEFF Research Database (Denmark)

    Huusom, Jakob Kjøbsted; Bialas, Dawid Jan; Jørgensen, John Bagterp

    2011-01-01

    In this paper we discuss a simple yet realistic benchmark plant for evaluation and comparison of advanced multivariable control for chemical and biochemical processes. The benchmark plant is based on recycle-separator-recycle systems for ethylene glycol production and implemented in Matlab...

  18. Towards benchmarking of multivariable controllers in chemical/biochemical industries: Plantwide control for ethylene glycol production

    DEFF Research Database (Denmark)

    Huusom, Jakob Kjøbsted; Bialas, Dawid Jan; Jørgensen, John Bagterp

    2011-01-01

    In this paper we discuss a simple yet realistic benchmark plant for evaluation and comparison of advanced multivariable control for chemical and biochemical processes. The benchmark plant is based on recycle-separator-recycle systems for ethylene glycol production and implemented in Matlab-Simulink...

  19. Production of viable cultures of Flavobacterium psychrophilum: approach and control.

    Science.gov (United States)

    Michel, C; Antonio, D; Hedrick, R P

    1999-06-01

    Although the fish pathogen Flavobacterium psychrophilum is a major source of concern in salmonid hatcheries, few studies have been conducted on its pathogenicity. Difficulties are often experienced when trying to control or quantify standard procedures for in vitro culture of the bacterium. Plate enumeration and counting chamber enumeration combined with epifluorescent microscopy with fluorescent dyes determined that no more than 25% of the bacterial cells present in the cultures were able to produce colonies on agar media. This was strongly dependent upon different medium components. Tryptone-enriched Anacker and Ordal medium proved more suitable than tryptone-yeast extract-salts with skimmed milk. Adding horse serum and trace elements in controlled proportions offered the most reproducible results. Viable but nonculturable forms were apparently not responsible for the difficulties in production of F. psychrophilum, but the cells were highly susceptible to osmotic conditions. Improvements in the media and careful handling of the bacteria in isotonic suspension media resulted in predictable production of viable bacteria and allowed an absorbance/colony-forming-units relation curve to be established.

  20. Oxygen-controlled Biosurfactant Production in a Bench Scale Bioreactor

    Science.gov (United States)

    de Kronemberger, Frederico Araujo; Anna, Lidia Maria Melo Santa; Fernandes, Ana Carolina Loureiro Brito; de Menezes, Reginaldo Ramos; Borges, Cristiano Piacsek; Freire, Denise Maria Guimarães

    Rhamnolipids have been pointed out as promising biosurfactants. The most studied microorganisms for the aerobic production of these molecules are the bacteria of the genus Pseudomonas. The aim of this work was to produce a rhamnolipid-type biosurfactant in a bench-scale bioreactor by one strain of Pseudomonas aeruginosa isolated from oil environments. To study the microorganism growth and production dependency on oxygen, a nondispersive oxygenation device was developed, and a programmable logic controller (PLC) was used to set the dissolved oxygen (DO) concentration. Using the data stored in a computer and the predetermined characteristics of the oxygenation device, it was possible to evaluate the oxygen uptake rate (OUR) and the specific OUR (SOUR) of this microorganism. These rates, obtained for some different DO concentrations, were then compared to the bacterial growth, to the carbon source consumption, and to the rhamnolipid and other virulence factors production. The SOUR presented an initial value of about 60.0 mg02/gdw h. Then, when the exponential growth phase begins, there is a rise in this rate. After that, the SOUR reduces to about 20.0 mg02/gdw h. The carbon source consumption is linear during the whole process.

  1. Coronavirus receptor switch explained from the stereochemistry of protein-carbohydrate interactions and a single mutation.

    Science.gov (United States)

    Bakkers, Mark J G; Zeng, Qinghong; Feitsma, Louris J; Hulswit, Ruben J G; Li, Zeshi; Westerbeke, Aniek; van Kuppeveld, Frank J M; Boons, Geert-Jan; Langereis, Martijn A; Huizinga, Eric G; de Groot, Raoul J

    2016-05-31

    Hemagglutinin-esterases (HEs) are bimodular envelope proteins of orthomyxoviruses, toroviruses, and coronaviruses with a carbohydrate-binding "lectin" domain appended to a receptor-destroying sialate-O-acetylesterase ("esterase"). In concert, these domains facilitate dynamic virion attachment to cell-surface sialoglycans. Most HEs (type I) target 9-O-acetylated sialic acids (9-O-Ac-Sias), but one group of coronaviruses switched to using 4-O-Ac-Sias instead (type II). This specificity shift required quasisynchronous adaptations in the Sia-binding sites of both lectin and esterase domains. Previously, a partially disordered crystal structure of a type II HE revealed how the shift in lectin ligand specificity was achieved. How the switch in esterase substrate specificity was realized remained unresolved, however. Here, we present a complete structure of a type II HE with a receptor analog in the catalytic site and identify the mutations underlying the 9-O- to 4-O-Ac-Sia substrate switch. We show that (i) common principles pertaining to the stereochemistry of protein-carbohydrate interactions were at the core of the transition in lectin ligand and esterase substrate specificity; (ii) in consequence, the switch in O-Ac-Sia specificity could be readily accomplished via convergent intramolecular coevolution with only modest architectural changes in lectin and esterase domains; and (iii) a single, inconspicuous Ala-to-Ser substitution in the catalytic site was key to the emergence of the type II HEs. Our findings provide fundamental insights into how proteins "see" sugars and how this affects protein and virus evolution.

  2. 77 FR 58567 - Information Collection Activities: Well Control and Production Safety Training, Submitted for...

    Science.gov (United States)

    2012-09-21

    ... of the paperwork requirements in the regulations under Subpart O, ``Well Control and Production... 250, Subpart O, Well Control and Production Safety Training. OMB Control Number: 1014-0008. Abstract... 30 CFR part 250, subpart O, Well Control and Production Safety Training. Responses are mandatory...

  3. Environmental controls of marine productivity hot spots around Antarctica

    Science.gov (United States)

    Arrigo, Kevin R.; van Dijken, Gert L.; Strong, Aaron L.

    2015-08-01

    Antarctic coastal polynyas are biologically rich ecosystems that support large populations of mammals and birds and are globally significant sinks of atmospheric carbon dioxide. To support local phytoplankton blooms, these highly productive ecosystems require a large input of iron (Fe), the sources of which are poorly known. Here we assess the relative importance of six different environmental factors in controlling the amount of phytoplankton biomass and rates of net primary production (NPP) in 46 coastal polynyas around Antarctica. Data presented here suggest that melting ice shelves are a primary supplier of Fe to coastal polynyas, with basal melt rates explaining 59% of the between-polynya variance in mean chlorophyll a (Chl a) concentration. In a multiple regression analysis, which explained 78% of the variance in chlorophyll a (Chl a) between polynyas, basal melt rate explained twice as much of the variance as the next most important variable. Fe upwelled from sediments, which is partly controlled by continental shelf width, was also important in some polynyas. Of secondary importance to phytoplankton abundance and NPP were sea surface temperature and polynya size. Surprisingly, differences in light availability and the length of the open water season explained little or none of the variance in either Chl a or NPP between polynyas. If the productivity of coastal polynyas is indeed sensitive to the release of Fe from melting ice shelves, future changes in ice shelf melt rates could dramatically influence Antarctic coastal ecosystems and the ability of continental shelf waters to sequester atmospheric carbon dioxide. This article was corrected on 26 AUG 2015. See the end of the full text for details.

  4. Target product profile choices for intra-domiciliary malaria vector control pesticide products: repel or kill?

    Directory of Open Access Journals (Sweden)

    Moore Sarah J

    2011-07-01

    Full Text Available Abstract Background The most common pesticide products for controlling malaria-transmitting mosquitoes combine two distinct modes of action: 1 conventional insecticidal activity which kills mosquitoes exposed to the pesticide and 2 deterrence of mosquitoes away from protected humans. While deterrence enhances personal or household protection of long-lasting insecticidal nets and indoor residual sprays, it may also attenuate or even reverse communal protection if it diverts mosquitoes to non-users rather than killing them outright. Methods A process-explicit model of malaria transmission is described which captures the sequential interaction between deterrent and toxic actions of vector control pesticides and accounts for the distinctive impacts of toxic activities which kill mosquitoes before or after they have fed upon the occupant of a covered house or sleeping space. Results Increasing deterrency increases personal protection but consistently reduces communal protection because deterrent sub-lethal exposure inevitably reduces the proportion subsequently exposed to higher lethal doses. If the high coverage targets of the World Health Organization are achieved, purely toxic products with no deterrence are predicted to generally provide superior protection to non-users and even users, especially where vectors feed exclusively on humans and a substantial amount of transmission occurs outdoors. Remarkably, this is even the case if that product confers no personal protection and only kills mosquitoes after they have fed. Conclusions Products with purely mosquito-toxic profiles may, therefore, be preferable for programmes with universal coverage targets, rather than those with equivalent toxicity but which also have higher deterrence. However, if purely mosquito-toxic products confer little personal protection because they do not deter mosquitoes and only kill them after they have fed, then they will require aggressive "catch up" campaigns, with

  5. Design, synthesis and in vitro evaluation of a series of α-substituted phenylpropanoic acid PPARγ agonists to further investigate the stereochemistry-activity relationship.

    Science.gov (United States)

    Ohashi, Masao; Nakagome, Izumi; Kasuga, Jun-Ichi; Nobusada, Hiromi; Matsuno, Kenji; Makishima, Makoto; Hirono, Shuichi; Hashimoto, Yuichi; Miyachi, Hiroyuki

    2012-11-01

    We previously demonstrated that the α-benzylphenylpropanoic acid-type PPARγ-selective agonist 6 exhibited a reversed stereochemistry-activity relationship, that is, the (R)-enantiomer is a more potent PPARγ agonist than the (S)-enantiomer, compared with structurally similar α-ethylphenylpropanoic acid-type PPAR agonists. Here, we designed, synthesized and evaluated the optically active α-cyclohexylmethylphenylpropanoic acid derivatives 7 and α-phenethylphenylpropanoic acid derivatives 8, respectively. Interestingly, α-cyclohexylmethyl derivatives showed reversal of the stereochemistry-activity relationship [i.e., (R) more potent than (S)], like α-benzyl derivatives, whereas α-phenethyl derivatives showed the 'normal' relationship [(S) more potent than (R)]. These results suggested that the presence of a branched carbon atom at the β-position with respect to the carboxyl group is a critical determinant of the reversed stereochemistry-activity relationship.

  6. Multivariate analysis of electron detachment dissociation and infrared multiphoton dissociation mass spectra of heparan sulfate tetrasaccharides differing only in hexuronic acid stereochemistry.

    Science.gov (United States)

    Oh, Han Bin; Leach, Franklin E; Arungundram, Sailaja; Al-Mafraji, Kanar; Venot, Andre; Boons, Geert-Jan; Amster, I Jonathan

    2011-03-01

    The structural characterization of glycosaminoglycan (GAG) carbohydrates by mass spectrometry has been a long-standing analytical challenge due to the inherent heterogeneity of these biomolecules, specifically polydispersity, variability in sulfation, and hexuronic acid stereochemistry. Recent advances in tandem mass spectrometry methods employing threshold and electron-based ion activation have resulted in the ability to determine the location of the labile sulfate modification as well as assign the stereochemistry of hexuronic acid residues. To facilitate the analysis of complex electron detachment dissociation (EDD) spectra, principal component analysis (PCA) is employed to differentiate the hexuronic acid stereochemistry of four synthetic GAG epimers whose EDD spectra are nearly identical upon visual inspection. For comparison, PCA is also applied to infrared multiphoton dissociation spectra (IRMPD) of the examined epimers. To assess the applicability of multivariate methods in GAG mixture analysis, PCA is utilized to identify the relative content of two epimers in a binary mixture.

  7. Controlled environment crop production - Hydroponic vs. lunar regolith

    Science.gov (United States)

    Bugbee, Bruce G.; Salisbury, Frank B.

    1989-01-01

    The potential of controlled environment crop production in a lunar colony is discussed. Findings on the effects of optimal root-zone and aerial environments derived as part of the NASA CELSS project at Utah State are presented. The concept of growing wheat in optimal environment is discussed. It is suggested that genetic engineering might produce the ideal wheat cultivar for CELSS (about 100 mm in height with fewer leaves). The Utah State University hydroponic system is outlined and diagrams of the system and plant container construction are provided. Ratio of plant mass to solution mass, minimum root-zone volume, maintenance, and pH control are discussed. A comparison of liquid hydrophonic systems and lunar regoliths as substrates for plant growth is provided. The physiological processes that are affected by the root-zone environment are discussed including carbon partitioning, nutrient availability, nutrient absorption zones, root-zone oxygen, plant water potential, root-produced hormones, and rhizosphere pH control.

  8. ASSESSMENT OF A WIND TURBINE INTELLIGENT CONTROLLER FOR ENHANCED ENERGY PRODUCTION AND POLLUTION REDUCTION

    Science.gov (United States)

    This study assessed the enhanced energy production which is possible when variable-speed wind turbines are electronically controlled by an intelligent controller for efficiency optimization and performance improvement. The control system consists of three fuzzy- logic controllers...

  9. Optimization of wind farm power production using innovative control strategies

    DEFF Research Database (Denmark)

    Duc, Thomas

    Wind energy has experienced a very significant growth and cost reduction over the past decade, and is now able to compete with conventional power generation sources. New concepts are currently investigated to decrease costs of production of electricity even further. Wind farm coordinated control...... is one of them; it is aimed at increasing the efficiency of a wind farm and decreasing the fatigue loads faced by wind turbines by reducing aerodynamic interactions between them. These objectives are achieved considering two different strategies: curtailing an upwind turbine to reduce the wind speed...... conditions. It is therefore not known to what extent these gains can be reproduced in a real wind farm where wind conditions are very fluctuating. The French national project SMARTEOLE constitutes one of the first attempts of implementing these strategies on a full scale wind farm. A ten month measurement...

  10. The meat product quality control by a polarimetric method

    Science.gov (United States)

    Blokhina, Anastasia A.; Ryzhova, Victoria A.; Korotaev, Valery V.; Kleshchenok, Maksim A.

    2017-05-01

    Analysis of the polarization characteristics of the scattered radiation of biological tissues in some cases provides a qualitatively new results in the study of biological samples. These results can be used in medicine and food industry. As a result of the work, it was determined that the high concentration of scattering particles, the nonuniformity of their dimensions, forms make the task of creating an adequate optical model of a biotissue quite difficult, though many interesting tissue properties can be potentially studied by means of polarized light. In this case, the method for control the freshness of meat samples is considered for by obtaining the Stokes parameters of the polarized radiation scattered forward by the meat product.

  11. Production planning and inventory control with remanufacturing and disposal

    NARCIS (Netherlands)

    E.A. van der Laan (Erwin); M. Salomon (Marc)

    1997-01-01

    textabstractIn this paper we consider a stochastic inventory system with production, remanufacturing, and disposal operations. Customer demands must either be fulfilled from the production of new products or by the remanufacturing of used products. Used products are either remanufactured or disposed

  12. Production planning and inventory control with remanufacturing and disposal

    NARCIS (Netherlands)

    E.A. van der Laan (Erwin); M. Salomon (Marc)

    1997-01-01

    textabstractIn this paper we consider a stochastic inventory system with production, remanufacturing, and disposal operations. Customer demands must either be fulfilled from the production of new products or by the remanufacturing of used products. Used products are either remanufactured or disposed

  13. Stereochemistry of N-Benzoyl-5-substituted-1-benzazepines Revisited: Synthesis of the Conformationally Biased Derivatives and Revision of the Reported Structure.

    Science.gov (United States)

    Tabata, Hidetsugu; Yoneda, Tetsuya; Tasaka, Tomohiko; Ito, Shigekazu; Oshitari, Tetsuta; Takahashi, Hideyo; Natsugari, Hideaki

    2016-04-15

    The syn (aR*,5R*) and anti (aS*,5R*) diastereomers of N-benzoyl-C5-substituted-1-benzazepines originating in the chiralities at C5 and the Ar-N(C═O) axis were first stereoselectively synthesized by biasing the conformation with a substituent at C6 and C9, respectively. Detailed examination of the stereochemistry (i.e., conformation and configuration) of these N-benzoyl-1-benzazepines by X-ray crystallographic analysis, VT NMR, and DFT calculations revealed new physicochemical aspects of these heterocycles including revision of the stereochemistry previously reported.

  14. Structure-activity relationship studies on acremomannolipin A, the potent calcium signal modulator with a novel glycolipid structure 2: Role of the alditol side chain stereochemistry.

    Science.gov (United States)

    Tsutsui, Nozomi; Tanabe, Genzoh; Gotoh, Genki; Morita, Nao; Nomura, Naohisa; Kita, Ayako; Sugiura, Reiko; Muraoka, Osamu

    2014-02-01

    Five alditol analogs 1b-1f of a novel glycolipid acremomannolipin A (1a), the potential Ca(2+) signal modulator isolated from Acremonium strictum, were synthesized by employing a stereoselective β-mannosylation of appropriately protected mannose with five hexitols with different stereochemistry, and their potential on modulating Ca(2+) signaling were evaluated. All these analogs were more potent compared to the original compound 1a, and proved that mannitol stereochemistry of 1a was not critical for the potent calcium signal modulating.

  15. Rhizobacterial characterization for quality control of eucalyptus biogrowth promoter products

    Directory of Open Access Journals (Sweden)

    Talyta Galafassi Zarpelon

    Full Text Available Abstract Plant growth-promoting rhizobacteria strains from special formulations have been used to optimize eucalyptus cutting production. To undertake quality control for the formulated products, the rhizobacterial strains should be characterized to assess their purity and authentication. In the present study, we characterized nine strains of rhizobacteria, including three Bacillus subtilis (S1, S2 and 3918, two Pseudomonas sp. (MF4 and FL2, P. putida (MF2, P. fulva (Ca, Frateuria aurantia (R1, and Stenotrophomonas maltophilia (CIIb. The strains were differentiated by colony morphology after 24 h of incubation in three different solid state culture media (glucose-nutritive agar, 523 medium and yeast extract-mannitol agar, sensitivity to a panel of 28 antibiotics (expressed according to the formation of inhibition halos of bacterial growth in the presence of antibiotics, and PCR-RFLP profiles of the 16S rDNA gene produced using nine restriction enzymes. It was possible to differentiate all nine strains of rhizobacteria using their morphological characteristics and sensitivity to antibiotics. The molecular analysis allowed us to separate the strains CIIb, FL2 and R1 from the strains belonging to the genera Bacillus and Pseudomonas. By using these three methods concomitantly, we were able to determine strain purity and perform the authentication.

  16. Rhizobacterial characterization for quality control of eucalyptus biogrowth promoter products.

    Science.gov (United States)

    Zarpelon, Talyta Galafassi; Guimarães, Lúcio Mauro da Silva; Alfenas-Zerbini, Poliane; Lopes, Eli Sidney; Mafia, Reginaldo Gonçalves; Alfenas, Acelino Couto

    Plant growth-promoting rhizobacteria strains from special formulations have been used to optimize eucalyptus cutting production. To undertake quality control for the formulated products, the rhizobacterial strains should be characterized to assess their purity and authentication. In the present study, we characterized nine strains of rhizobacteria, including three Bacillus subtilis (S1, S2 and 3918), two Pseudomonas sp. (MF4 and FL2), P. putida (MF2), P. fulva (Ca), Frateuria aurantia (R1), and Stenotrophomonas maltophilia (CIIb). The strains were differentiated by colony morphology after 24h of incubation in three different solid state culture media (glucose-nutritive agar, 523 medium and yeast extract-mannitol agar), sensitivity to a panel of 28 antibiotics (expressed according to the formation of inhibition halos of bacterial growth in the presence of antibiotics), and PCR-RFLP profiles of the 16S rDNA gene produced using nine restriction enzymes. It was possible to differentiate all nine strains of rhizobacteria using their morphological characteristics and sensitivity to antibiotics. The molecular analysis allowed us to separate the strains CIIb, FL2 and R1 from the strains belonging to the genera Bacillus and Pseudomonas. By using these three methods concomitantly, we were able to determine strain purity and perform the authentication.

  17. PREVENTION AND CONTROL OF DIMETHYLAMINE VAPORS EMISSION: HERBICIDE PRODUCTION PLANT

    Directory of Open Access Journals (Sweden)

    Zorana Arsenijević

    2008-11-01

    Full Text Available The widely used herbicide, dimethylamine salt of 2,4-dichlorophenoxy acetic acid (2,4-D-DMA, is usually prepared by mixing a dimethylamine (DMA aqueous solution with a solid 2,4-dichlorophenoxy acetic acid (2,4-D. The vapors of the both, reactants and products, are potentially hazardous for the environment. The contribution of DMA vapors in overall pollution from this process is most significant, concerning vapor pressures data of these pollutants. Therefore, the control of the air pollution in the manufacture and handling of methylamines is very important. Within this paper, the optimal air pollution control system in preparation of 2,4-D-DMA was developed for the pesticides manufacturing industry. This study employed the simple pollution prevention concept to reduce the emission of DMA vapors at the source. The investigations were performed on the pilot plant scale. To reduce the emission of DMA vapors, the effluent gases from the herbicide preparation zone were passed through the packed bed scrubber (water - scrubbing medium, and the catalytic reactor in sequence. The end result is a substantially improved air quality in the working area, as well as in the urbanized areas located near the chemical plant.

  18. Control of Methane Production and Exchange in Northern Peatlands

    Science.gov (United States)

    Crill, Patrick

    1997-01-01

    This proposal has successfully supported studies that have developed unique long ten-n datasets of methane (CH4) emissions and carbon dioxide (CO2) exchange in order to quantify the controls on CH4 production and exchange especially the linkages to the carbon cycle in northern peatlands. The primary research site has been a small fen in southeastern New Hampshire where a unique multi-year data baseline of CH4 flux measurements was begun (with NASA funding) in 1989. The fen has also been instrumented for continuous hydrological and meteorological observations and year-round porewater sampling. Multiyear datasets of methane flux are very valuable and very rare. Datasets using the same sampling techniques at the same sites are the only way to assess the effect of the integrated ecosystem response to climatological variability. The research has had two basic objectives: 1. To quantify the effect of seasonal and interannual variability on CH4flux. 2. To examine process level controls on methane dynamics.

  19. A lean production control system for high-variety/low-volume environments : a case study implementation

    NARCIS (Netherlands)

    Slomp, J.; Bokhorst, J.A.C.; Germs, R.

    2009-01-01

    Due to the success of lean manufacturing, many companies are interested in implementing a lean production control system. Lean production control principles include the levelling of production, the use of pull mechanisms and takt time control. These principles have mainly been applied in high volume

  20. A lean production control system for high-variety/low-volume environments : a case study implementation

    NARCIS (Netherlands)

    Slomp, J.; Bokhorst, J.A.C.; Germs, R.

    2009-01-01

    Due to the success of lean manufacturing, many companies are interested in implementing a lean production control system. Lean production control principles include the levelling of production, the use of pull mechanisms and takt time control. These principles have mainly been applied in high volume

  1. Logistic planning and control of reworking perishable production defectives

    NARCIS (Netherlands)

    R.H. Teunter (Ruud); S.D.P. Flapper

    2001-01-01

    textabstractWe consider a production line that is dedicated to a single product. Produced lots may be non-defective, reworkable defective, or non-reworkable defective. The production line switches between production and rework. After producing a fixed number (N) of lots, all reworkable defective lot

  2. Logistic planning and control of reworking perishable production defectives

    NARCIS (Netherlands)

    R.H. Teunter (Ruud); S.D.P. Flapper

    2001-01-01

    textabstractWe consider a production line that is dedicated to a single product. Produced lots may be non-defective, reworkable defective, or non-reworkable defective. The production line switches between production and rework. After producing a fixed number (N) of lots, all reworkable defective

  3. The last gasp: controlling water production in wells

    Energy Technology Data Exchange (ETDEWEB)

    Lea, N.

    2002-03-01

    Produced water in oil and gas wells is highly undesirable. As it grows it saps productivity until wells finally shut-in. This article discusses a number of methods that have been tried over time with varying degrees of success and failure to control water influx into wells with operating and completion techniques. Water blocking chemicals that form downhole rubber-like barriers, sealing the water-producing zone from the oil and gas producing zones have had some recent successes, but performance has not always lived up to the salesman's claims. More success has been achieved with the downhole oil/water separation technology developed during the late 1990s by C{sub F}ER Technologies, which has since been licensed to Baker Hughes and Schlumberger. This technology essentially captures the hydrocarbon fluids into two streams -- one stream is clean water, which is then reinjected downhole, and the second oil-rich stream is brought to the surface where a hydrocyclone uses centrifugal forces to separate the oil from the water. Among the water blocking chemical technologies UNOCAL's gel placement technique has had some success. Once the produced water's origin is determined from production data, a liquid gel is injected downhole followed by nitrogen gas which helps position the gel within the wellbore while it hardens. Ideally, the produced water will enter the wellbore beneath the hardened gel while the oil or gas is above the gel plug. Aqueolic Canada's 'Direxit' is a newer water blocking chemical with a viscosity of one to three centipoise, resulting in low injection pressure. To eliminate problems with swelling clays Direxit can be also mixed with potassium chloride. Aqueolic has also filed notice of testing 'Bloxit' a water-blocking polymer with a density less than water, thus having the ability to float above a water producing zone.

  4. Production of Aphanius mento (Heckel, 1843 under controlled conditions

    Directory of Open Access Journals (Sweden)

    Soner Sezen

    2012-06-01

    Full Text Available In this study, it was aimed to determine the adaptation capability to controlled conditions, reproductive behaviors, and production ofAphanius mentocaught from Kirkgoz Springs, Antalya. Fish material for broodstock were caught using fine mesh tulle net and bag net with 2.5mm mesh size. Twenty five female and 10 male breeding fish acclimated to experimental conditions in Aquarium Department Unit of Ministryof Food, Agriculture and Livestock Mediterranean Fisheries Research Production and Training Institute were spawned by providing egg collectorsto the tank. Aphanius mentoeggs were spherical, transparent and sticky. Examination with the microscope revealed that the eggs were fullof pale yellow egg yolk with 7-8 lipid droplets and had fibrous sticking filaments on the surface. The average egg diameter was 1.59±0.50 mm(n=8. Hatching were observed at 11th day at 22.5±1.0ºC water temperature whereas at 8th day at 27.0±0.45ºC. Total length of newly hatchedlarvae was 5.1±0.07 mm, and swimming were competed at 4th day. Average size of one-week larvae was 5.6±0.2 mm. At this stage fins werefully developed, the larvae were able to swim freely and take exogenous food. Mean length of the fish was 2.7±0.2 cm on 7th month and a juvenilefish had an appearance of morphologically mature fish.

  5. Direct bis-arylation of cyclobutanecarboxamide via double C-H activation: an auxiliary-aided diastereoselective Pd-catalyzed access to trisubstituted cyclobutane scaffolds having three contiguous stereocenters and an all-cis stereochemistry.

    Science.gov (United States)

    Parella, Ramarao; Gopalakrishnan, Bojan; Babu, Srinivasarao Arulananda

    2013-12-06

    An auxiliary-aided Pd-catalyzed highly diastereoselective double C-H activation and direct bis-arylation of methylene C(sp(3))-H bonds of cyclobutanecarboxamides and the syntheses of several novel trisubstituted cyclobutanecarboxamide scaffolds having an all-cis stereochemistry are reported. Extensive screening of various auxiliaries and reaction conditions was performed to firmly establish the optimized reaction conditions required for effecting the mono- or double C-H arylation of cyclobutanecarboxamides. The auxiliary-attached cyclobutanecarboxamides 15a, 15g, and 15h, prepared from the auxiliaries such as, 8-aminoquinoline, 2-(methylthio)aniline, and N',N'-dimethylethane-1,2-diamine were found to undergo an efficient direct bis-arylation. The Pd-catalyzed arylation reaction of N-(quinolin-8-yl)cyclobutanecarboxamide 15a with one equivalent or more of aryl iodides, afforded the corresponding bis-arylated cyclobutanecarboxamides 16a-y. Nevertheless, the Pd-catalyzed arylation of 15a with just 0.5 equiv of the aryl iodides 13a, 13b, 13e, and 13m, selectively gave the corresponding monoarylated cyclobutanecarboxamides 17a-17d. The Pd-catalyzed arylation of 15g or 15h with one equivalent or more of aryl iodides afforded the bis-arylated cyclobutanecarboxamides 19a-19c and 21a-21m, respectively. However, the Pd-catalyzed arylations of compounds 15g or 15h with just 0.5 equiv of aryl iodides were ineffective. The stereochemistry of compounds obtained in this work was unambiguously assigned from the X-ray structures of representative products.

  6. Real Time Part Input Control of a Pull Production System by Finding IF-THEN Rules

    Science.gov (United States)

    Ramli, Rizauddin; Yamamoto, Hidehiko; Abu Qudeiri, Jaber

    This paper considers the part input problem of a production system where two Flexible Transfer Lines (FTLs) consisting of an up-stream production line and a down-stream production line while operating under Just In Time (JIT) production management. The up-stream production line processes the raw material after receiving them from suppliers, and after processing them, delivers the processed product to a down-stream production line via a conveyer. In this paper, we have proposed a novel idea for a part input real time control system, known as Algorithm for Real Time Control of Part Input Systems (ARTCOPS). The algorithm is useful when FTLs are in operation under a production order that is different from the pre-decided production schedule. Simulations of virtual production systems have been carried out to verify that ARTCOPS is useful in real time control, although the production orders are different from the pre-decided production scheduling.

  7. 77 FR 22602 - Information Collection Activities: Well Control and Production Safety Training, Submitted for...

    Science.gov (United States)

    2012-04-16

    ... paperwork requirements in the regulations under Subpart O, ``Well Control and Production Safety Training... Control and Production Safety Training. OMB Control Number: 1014-0008. Abstract: The Outer Continental... Bureau of Safety and Environmental Enforcement (BSEE) Information Collection Activities: Well Control...

  8. Product Distribution Theory for Control of Multi-Agent Systems

    Science.gov (United States)

    Lee, Chia Fan; Wolpert, David H.

    2004-01-01

    Product Distribution (PD) theory is a new framework for controlling Multi-Agent Systems (MAS's). First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint stare of the agents. Accordingly we can consider a team game in which the shared utility is a performance measure of the behavior of the MAS. For such a scenario the game is at equilibrium - the Lagrangian is optimized - when the joint distribution of the agents optimizes the system's expected performance. One common way to find that equilibrium is to have each agent run a reinforcement learning algorithm. Here we investigate the alternative of exploiting PD theory to run gradient descent on the Lagrangian. We present computer experiments validating some of the predictions of PD theory for how best to do that gradient descent. We also demonstrate how PD theory can improve performance even when we are not allowed to rerun the MAS from different initial conditions, a requirement implicit in some previous work.

  9. Ion beam polarization in storage rings. Production, controlling and preservation

    Energy Technology Data Exchange (ETDEWEB)

    Prozorov, A. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics; Labzowsky, L. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics]|[St. Petersburg Nuclear Physics Institute (Russian Federation); Plunien, G. [Technische Univ. Dresden (Germany). Inst. fuer Theoretische Physik; Liesen, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.; Bosch, F. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Fritzsche, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.]|[Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany); Surzhykov, A. [Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany)

    2008-03-15

    The present paper reports on the actual status of the theoretical concepts for the production of polarized heavy ion beams in storage rings and for methods to control online the degree of polarization as well as investigations of the preservation of the polarization during the ion movement across the magnetic system of the ring. It is argued that for hydrogen-like ions beam polarization can be built up efficiently by optical pumping of the Zeeman sublevels of ground-state hyperfine levels and that the maximal achievable nuclear polarization exceeds 90%. Of special interest are polarized helium-like ions which can be produced by the capture of one electron, because in selected cases parity nonconservation effects are found to be of unprecedented size in Atomic Physics. The measurements of these effects require online-diagnostics of the degree of the ion beam polarization. It is shown that this can be accomplished by an online-detection of the linear polarization of the X-rays which are emitted with the capture of the electron. In order to investigate the preservation of the polarization of the ions stored in the ring, the concept of an instantaneous quantization axis is introduced. The dynamics of this axis and the behaviour of the polarization with respect to it are explored in detail. (orig.)

  10. Ion beam polarization in storage rings. Production, controlling and preservation

    Energy Technology Data Exchange (ETDEWEB)

    Prozorov, A. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics; Labzowsky, L. [St. Petersburg State Univ. (Russian Federation). V.A. Fock Research Institute for Physics]|[St. Petersburg Nuclear Physics Institute (Russian Federation); Plunien, G. [Technische Univ. Dresden (Germany). Inst. fuer Theoretische Physik; Liesen, D. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.; Bosch, F. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Fritzsche, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Heidelberg Univ. (Germany). Physikalisches Inst.]|[Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany); Surzhykov, A. [Max-Planck Insitute of Nuclear Physics, Heidelberg (Germany)

    2008-03-15

    The present paper reports on the actual status of the theoretical concepts for the production of polarized heavy ion beams in storage rings and for methods to control online the degree of polarization as well as investigations of the preservation of the polarization during the ion movement across the magnetic system of the ring. It is argued that for hydrogen-like ions beam polarization can be built up efficiently by optical pumping of the Zeeman sublevels of ground-state hyperfine levels and that the maximal achievable nuclear polarization exceeds 90%. Of special interest are polarized helium-like ions which can be produced by the capture of one electron, because in selected cases parity nonconservation effects are found to be of unprecedented size in Atomic Physics. The measurements of these effects require online-diagnostics of the degree of the ion beam polarization. It is shown that this can be accomplished by an online-detection of the linear polarization of the X-rays which are emitted with the capture of the electron. In order to investigate the preservation of the polarization of the ions stored in the ring, the concept of an instantaneous quantization axis is introduced. The dynamics of this axis and the behaviour of the polarization with respect to it are explored in detail. (orig.)

  11. Using Empirical Rules from 13C NMR Analysis to Determine the Stereochemistry of the Epoxide Located at the 5,6-position of Decalinic Systems

    Directory of Open Access Journals (Sweden)

    Raquel M. Cravero

    2000-03-01

    Full Text Available An empiric rule derived from the analysis of the 13C NMR spectral data, allowed us to determine 5,6-epoxide stereochemistry on decalinic systems and a discussion of the scope and limitations of this rule and its extension to other carbon squeletons, is presented.

  12. Prediction and determination of the stereochemistry of the 1,3,5-trimethyl-substituted alkyl chain in verucopeptin, a microbial metabolite.

    Science.gov (United States)

    Yoshimura, Aya; Kishimoto, Shinji; Nishimura, Shinichi; Otsuka, Saori; Sakai, Yuki; Hattori, Akira; Kakeya, Hideaki

    2014-08-01

    For the prediction of the relative stereochemistry of 1,3-dimethyl substitution in alkyl chains, a simple approach based on (1)H NMR data was recently proposed; Δδ values of methylene protons located between methyl-substituted methine carbons can be diagnostic for predicting it. Here we applied this empirical "geminal proton rule" to verucopeptin, a lipopeptide from Streptomyces sp. To determine the absolute stereochemistry of the 1,3,5-trimethyl-substituted alkyl chain in verucopeptin, we converted the corresponding alkyl chain to a carboxylic acid by oxidative cleavage. The geminal proton rule clearly predicted the relative stereochemistry as 31S*,33S*,35R*. This prediction was definitely confirmed by synthesizing four possible diastereomers and comparing their NMR spectra. Furthermore, we reinvestigated the geminal proton rule using reported compounds and our synthesized compounds. Our result strongly suggests that the rule was solid, at least for predicting the stereochemistry of 2,4-dimethylated and 2,4,6-trimethylated fatty acids.

  13. Assignment of hexuronic acid stereochemistry in synthetic heparan sulfate tetrasaccharides with 2-O-sulfo uronic acids using electron detachment dissociation

    NARCIS (Netherlands)

    Agyekum, Isaac; Patel, Anish B.; Zong, Chengli; Boons, Geert Jan; Amster, I. Jonathan

    2015-01-01

    The present work focuses on the assignment of uronic acid stereochemistry in heparan sulfate (HS) oligomers. The structural elucidation of HS glycosaminoglycans is the subject of considerable importance due to the biological and biomedical significance of this class of carbohydrates. They are highly

  14. Woodward-Hoffmann's Stereochemistry of Electrocyclic Reactions: From Day 1 to the JACS Receipt Date (May 5, 1964 to November 30, 1964).

    Science.gov (United States)

    Seeman, Jeffrey I

    2015-12-04

    The publication in January 1965 of the first Woodward-Hoffmann paper, The Stereochemistry of Electrocyclic Reactions, ushered into organic chemistry both an explanation of the stereochemistry and "allowedness" or "forbiddenness" of concerted reactions and an impetus for untold numbers of research projects. In the current paper, details of the collaboration between R. B. Woodward and R. Hoffmann, from when they first met to discuss the solution to the "no-mechanism problem" to the date their first paper was received in the offices of the Journal of the American Chemical Society, will be discussed and analyzed. The primary focus will be on the historically relevant extant documents from the early 1960s. These include Hoffmann's laboratory notebooks describing his research, including his extended Hückel calculations used to explain and predict the stereochemistry of electrocyclic reactions. Drafts of the Stereochemistry of Electrocyclic Reactions paper and letters and notes by Woodward, Jerome Berson, and others will further illuminate the development of this first Woodward-Hoffmann paper.

  15. Design and Implementation of a Self-Directed Stereochemistry Lesson Using Embedded Virtual Three-Dimensional Images in a Portable Document Format

    Science.gov (United States)

    Cody, Jeremy A.; Craig, Paul A.; Loudermilk, Adam D.; Yacci, Paul M.; Frisco, Sarah L.; Milillo, Jennifer R.

    2012-01-01

    A novel stereochemistry lesson was prepared that incorporated both handheld molecular models and embedded virtual three-dimensional (3D) images. The images are fully interactive and eye-catching for the students; methods for preparing 3D molecular images in Adobe Acrobat are included. The lesson was designed and implemented to showcase the 3D…

  16. Quality Control & Standard Compliance of the Machinery and Products Used for Vector Control

    OpenAIRE

    Ahmet Kiremitçigil, Osman Nuri

    2015-01-01

    Vector control; under the main title of “public health” is a highly complicated and “know how based” process. It is based on more than a dozen of scientific disciplines. As this process is effecting public health and the future of the environment directly, it must be executed in the light of scientific integrity. How much progress could be made in 30 years? Does new regulations contribute to the improvement to the quality of the products or equipment standards? Is it possible to detect the am...

  17. Biomass performance : monitoring and control in bio-pharmaceutical production

    NARCIS (Netherlands)

    Neeleman, R.

    2002-01-01

    The primary concern in the pharmaceutical industry is not the optimisation of product yield or the reduction of manufacturing cost, but the production of a product of consistently high quality. This has resulted in 'process monitoring' becoming an integral part of process operation. In this

  18. Biomass Performance : Monitoring and Control in Pharmaceutical Production

    NARCIS (Netherlands)

    Neeleman, R.

    2002-01-01

    The primary concern in the pharmaceutical industry is not the optimisation of product yield or the reduction of manufacturing cost, but the production of a product of consistently high quality. This has resulted in 'process monitoring' becoming an integral part of process operation. In this thesis p

  19. Monitoring and control of protein production in fungi

    DEFF Research Database (Denmark)

    Schalén, Martin

    : • How is protein production affected on a single cell level due to environmental stress factors? • How can we improve heterologous protein production in filamentous fungi, and how does production in Aspergillus nidulans compare to protein production in the industrially exploited Aspergillus niger...... stress elements on the production of heterologous proteins in S. cerevisiae is investigated. A fluorescent reporter strain, producing an intracellular protein linked to tagRFP from the glycolytic PGK1 promoter is constructed. This strain is used to monitor the level of production in each cell when...... exposed to environmental stress. The cells are grown in shake flasks as well as bioreactors and protein levels are analyzed by flow cytometry. It is demonstrated that the fluorescent reporter can be used to study the effects on stress elements on a population basis. Production of the protein was affected...

  20. Resolution, absolute stereochemistry and molecular pharmacology of the enantiomers of ATPA.

    Science.gov (United States)

    Stensbøl, T B; Borre, L; Johansen, T N; Egebjerg, J; Madsen, U; Ebert, B; Krogsgaard-Larsen, P

    1999-09-10

    (RS)-2-Amino-3-(5-tert-butyl-3-hydroxy-4-isoxazolyl)propionic acid (ATPA), an analogue of (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA). has previously been shown to be a relatively weak AMPA receptor agonist and a very potent agonist at the GluR5 subtype of kainic acid-preferring (S)-glutamic acid ((S)-Glu) receptors. We report here the separation of (+)- and (-)-ATPA, obtained at high enantiomeric purity (enantiomeric excess values of 99.8% and > 99.8%, respectively) using chiral chromatography, and the unequivocal assignment of the stereochemistry of (S)-(+)-ATPA and (R)-(-)-ATPA. (S)- and (R)-ATPA were characterized in receptor binding studies using rat brain membranes, and electrophysiologically using the rat cortical wedge preparation and cloned AMPA-preferring (GluR1, GluR3, and GluR4) and kainic acid-preferring (GluR5, GluR6, and GluR6 + KA2) receptors expressed in Xenopus oocytes. In the cortical wedge, (S)-ATPA showed AMPA receptor agonist effects (EC50 = 23 microM) approximately twice as potent as those of ATPA. (R)-ATPA antagonized depolarizations induced by AMPA (Ki = 253 microM) and by (S)-ATPA (Ki = 376 microM), and (R)-ATPA antagonized the biphasic depolarizing effects induced by kainic acid (Ki = 301 microM and 1115 microM). At cloned AMPA receptors, (S)-ATPA showed agonist effects at GluR3 and GluR4 with EC50 values of approximately 8 microM and at GluR1 (EC50 = 22 microM), producing maximal steady state currents only 5.4-33% of those evoked by kainic acid. (R)-ATPA antagonized currents evoked by kainic acid at cloned AMPA receptor subtypes with Ki values of 33-75 microM. (S)-ATPA produced potent agonist effects at GluR5 (EC50 = 0.48 microM). Due to desensitization of GluR5 receptors, which could not be fully prevented by treatment with concanavalin A, (S)-ATPA-induced agonist effects were normalized to those of kainic acid. Under these circumstances, maximal currents produced by (S)-ATPA and kainic acid were not

  1. 7 CFR 58.149 - Alternate quality control programs for dairy products.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Alternate quality control programs for dairy products... FOR GRADES OF DAIRY PRODUCTS 1 General Specifications for Dairy Plants Approved for USDA Inspection... for dairy products. (a) When a plant has in operation an acceptable quality control program which...

  2. 21 CFR 111.135 - What quality control operations are required for product complaints?

    Science.gov (United States)

    2010-04-01

    ... product complaints? Quality control operations for product complaints must include reviewing and approving... 21 Food and Drugs 2 2010-04-01 2010-04-01 false What quality control operations are required for product complaints? 111.135 Section 111.135 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...

  3. Optimal control policies for continuous review production-inventory models

    OpenAIRE

    Germs, Remco; Foreest, Nicky D. van

    2012-01-01

    In this paper, we consider a stochastic version of a single-item production-inventory system in which the demand process is a mixture of a compound Poisson process and a constant demand rate. This model generalizes classical continuous-review single product inventory models with infinite planning horizon such as the EOQ model or production-inventory models with compound Poisson demand. We establish for the first time conditions on the inventory costs and the demand distribution such that the ...

  4. Biomass Performance : Monitoring and Control in Pharmaceutical Production

    OpenAIRE

    Neeleman, R.

    2002-01-01

    The primary concern in the pharmaceutical industry is not the optimisation of product yield or the reduction of manufacturing cost, but the production of a product of consistently high quality. This has resulted in 'process monitoring' becoming an integral part of process operation. In this thesis process monitoring is one of the central themes, from monitoring the environment of the micro-organisms to monitoring the micro-organisms themselves. The latter is called monitoring biomass performa...

  5. Optimal control policies for continuous review production-inventory models

    OpenAIRE

    Germs, Remco; Foreest, Nicky D. van

    2012-01-01

    In this paper, we consider a stochastic version of a single-item production-inventory system in which the demand process is a mixture of a compound Poisson process and a constant demand rate. This model generalizes classical continuous-review single product inventory models with infinite planning horizon such as the EOQ model or production-inventory models with compound Poisson demand. We establish for the first time conditions on the inventory costs and the demand distribution such that the ...

  6. Weed Control Strategies for Organic Peanut Production and Transition: A Lesson in Basic Agronomy

    Science.gov (United States)

    Weed control in organic peanut production is difficult and costly. The only production inputs that consistently improved weed management in organic peanut production were modified production practices and intense cultivation with a tine weeder. Research trials evaluated row patterns, seeding rates...

  7. A new model of the harmonic control based on Hadamard product

    Institute of Scientific and Technical Information of China (English)

    Xinjin LIU; Yun ZOU; Xiefei YAN

    2009-01-01

    In terms of Hadamard product, a new model is proposed for the control of connection coefficients of the state variables of the systems. The control law to stabilize the systems via the regulations of connection coefficients is obtained via a Hadamard product involved bilinear matrix inequalities. This new control model may be of significant applications in many fields, especially may be of some special sense in the emergency control such as isolation and obstruction control.

  8. Stereochemistry of 16a-Hydroxyfriedelin and 3-Oxo-16-methylfriedel-16-ene Established by 2D NMR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Vagner Fernandes Knupp

    2009-02-01

    Full Text Available Friedelin (1, 3b-friedelinol (2, 28-hydroxyfriedelin (3, 16a-hydroxyfriedelin (4, 30-hydroxyfriedelin (5 and 16a,28-dihydroxyfriedelin (6 were isolated through fractionation of the hexane extract obtained from branches of Salacia elliptica. After a week in CDCl3 solution, 16a-hydroxyfriedelin (4 reacted turning into 3-oxo-16-methylfriedel-16-ene (7. This is the first report of a dehydration followed by a Nametkin rearrangement of a pentacyclic triterpene in CDCl3 solution occurring in the NMR tube. These seven pentacyclic triterpenes was identified through NMR spectroscopy and the stereochemistry of compound 4 and 7 was established by 2D NMR (NOESY spectroscopy and mass spectrometry (GC-MS. It is also the first time that all the 13C-NMR and 2D NMR spectral data are reported for compounds 4 and 7.

  9. Anisotropy effect of three-membered rings in (1)H NMR spectra: quantification by TSNMRS and assignment of the stereochemistry.

    Science.gov (United States)

    Kleinpeter, Erich; Krüger, Stefanie; Koch, Andreas

    2015-05-07

    The spatial magnetic properties (through space NMR shieldings, TSNMRSs) of cyclopropane; of the heteroanalogous oxirane, thiirane, and aziridine; and of various substituted mono-, dis-, and tris-cyclic analogues have been computed by the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and visualized as iso-chemical-shielding surfaces (ICSSs) of various size and direction. The TSNMRS values, thus obtained, can be employed to visualize the anisotropy (ring current) effect of the cyclopropane ring moiety. This approach has been employed to qualify and quantify substituent influences and contributions of appropriate ring heteroatoms O, NH, and S on the anisotropy (ring current) effect of three-membered ring moieties, and to assign the stereochemistry of mono-, bis-, and tris-cyclic structures containing cyclopropane as a structural element. Characteristic examples are included.

  10. Classroom Enters the Courtroom: Stereochemistry of SN1 and SN2 Reactions in Enantiomer Patent Litigations of the Antidepressant Escitalopram.

    Science.gov (United States)

    Michman, Elisheva; Agranat, Israel

    2016-01-01

    The role of elementary stereochemistry is illustrated in the patent litigations of the blockbuster antidepressant drug escitalopram oxalate. An undergraduate student of organic chemistry would recognize the stereochemical courses of the intramolecular SN 2 and SN 1 reactions of the single-enantiomer (S)-diol intermediate in the synthesis of the blockbuster antidepressant drug escitalopram oxalate: retention of configuration of the chiral carbon atom under basic conditions and racemization under acidic conditions, respectively. He/she, in searching for a stereoselective ring-closure reaction of the enantiomeric diol, will think of an SN 2 reaction in a basic medium. From these points of view, the process claim in the enantiomer patents of escitalopram is obvious/lacks an inventive step. An organic chemistry examination problem based on this scenario is offered.

  11. Increasing Student Interest and Comprehension of Production Planning and Control and Operations Performance Measurement Concepts Using a Production Line Game

    Science.gov (United States)

    Cox, James F., III; Walker, Edward D., II

    2005-01-01

    Production planning and control (PPC) systems and operations performance measures are topics that students generally find both boring and difficult to understand. In the article, the authors present a production line game that they have found to be an effective tool to increase student interest in the topics as well as student comprehension. The…

  12. Applicability aspects of workload control in job shop production

    NARCIS (Netherlands)

    Henrich, P.

    2005-01-01

    The term Job Shop Production (JSP) describes a manufacturing environment that produces piece goods in small batches. It is a common manufacturing environment in small and medium-sized enterprises (SMEs). The incoming orders often differ in the number of ordered products, their design, process charac

  13. Production planning and control of closed-loop supply chains

    NARCIS (Netherlands)

    K. Inderfurth (Karl); R.H. Teunter (Ruud)

    2001-01-01

    textabstractMore and more supply chains emerge that include a return flow of materials. Many original equipment manufacturers are nowadays engaged in the remanufacturing business. In many process industries, production defectives and by-products are reworked. These closed-loop supply chains deserve

  14. Dynamic Product Assembly and Inventory Control for Maximum Profit

    CERN Document Server

    Neely, Michael J

    2010-01-01

    We consider a manufacturing plant that purchases raw materials for product assembly and then sells the final products to customers. There are M types of raw materials and K types of products, and each product uses a certain subset of raw materials for assembly. The plant operates in slotted time, and every slot it makes decisions about re-stocking materials and pricing the existing products in reaction to (possibly time-varying) material costs and consumer demands. We develop a dynamic purchasing and pricing policy that yields time average profit within epsilon of optimality, for any given epsilon>0, with a worst case storage buffer requirement that is O(1/epsilon). The policy can be implemented easily for large M, K, yields fast convergence times, and is robust to non-ergodic system dynamics.

  15. Structural investigations into the stereochemistry and activity of a phenylalanine-2,3-aminomutase from Taxus chinensis.

    Science.gov (United States)

    Wybenga, Gjalt G; Szymanski, Wiktor; Wu, Bian; Feringa, Ben L; Janssen, Dick B; Dijkstra, Bauke W

    2014-05-20

    Phenylalanine-2,3-aminomutase (PAM) from Taxus chinensis, a 4-methylidene-imidazole-5-one (MIO)-dependent enzyme, catalyzes the reversible conversion of (S)-α-phenylalanine into (R)-β-phenylalanine via trans-cinnamic acid. The enzyme also catalyzes the direct addition of ammonia to trans-cinnamic acid, a reaction that can be used for the preparation of β-amino acids, which occur as frequent constituents of bioactive compounds. Different hypotheses have been formulated to explain the stereochemistry of the PAM-catalyzed reaction, but structural evidence for these hypotheses is lacking. Furthermore, it remains unclear how the PAM MIO group is formed from the three-amino acid (A-S-G) sequence motif. For these reasons, we elucidated PAM three-dimensional (3D) structures with a bound (R)-β-phenylalanine analogue and with bound trans-cinnamic acid. In addition, 3D structures of the (inactive) Y322A and N231A mutants of PAM were elucidated, which were found to be MIO-less. We conclude that the stereochemistry of the PAM-catalyzed reaction originates from the enzyme's ability to bind trans-cinnamic acid in two different orientations, with either the si,si face or the re,re face directed toward the MIO group, as evidenced by two distinct carboxylate binding modes. The results also suggest that the N231 side chain promotes MIO group formation by increasing the nucleophilicity of the G177 N atom through acidification of the amide proton.

  16. Biological control of soilborne diseases in organic potato production using hypovirulent strains of Rhizoctonia solani

    Science.gov (United States)

    Soilborne diseases are persistent problems in potato production and alternative management practices are needed, particularly in organic production, where control options are limited. Selected biocontrol organisms, including two naturally-occurring hypovirulent strains of Rhizoctonia solani (Rhs1a1 ...

  17. Biological control of soilborne diseases in organic potato production as affected by varying environmental conditions

    Science.gov (United States)

    Soilborne diseases are persistent problems in potato production and alternative management practices are needed, particularly in organic production, where control options are limited. Selected biocontrol organisms, including two naturally-occurring hypovirulent strains of Rhizoctonia solani (Rhs1a1 ...

  18. HACCP system in radiation-hygiene control of pig production

    Directory of Open Access Journals (Sweden)

    Mitrović Radosav

    2005-01-01

    Full Text Available The paper presents instructive methodology for introducing and realizing the HACCP system in pig production, as a typical representative of intensive breeding, with the objective of establishing radiation-hygiene supervision. Attention was focused on the type of pig diet as the key link in the production chain, in fact the selection of the raw material components necessary in the production of pig feed concentrates for intense breeding conditions, and on the establishment of a certain radiation-hygiene balance through prognostic-selective methodology, as a guarantee of radiation safety.

  19. 76 FR 12916 - Benzocaine; Weight Control Drug Products for Over-the-Counter Human Use

    Science.gov (United States)

    2011-03-09

    ... benzocaine be classified as nonmonograph at any concentration for use in OTC weight control drug products... daily) Group 4: Glucose hard candy containing benzocaine, caffeine, and vitamins (benzocaine...

  20. Smart Product Design and Production Control for Effective Mass Customization in the Industry 4.0 Concept

    Directory of Open Access Journals (Sweden)

    Zawadzki Przemysław

    2016-09-01

    Full Text Available The paper presents a general concept of smart design and production control as key elements for efficient operation of a smart factory. The authors present various techniques that aid the design process of individualized products and organization of their production in the context of realization of the mass customization strategy, which allows a shortened time of development for a new product. Particular attention was paid to integration of additive manufacturing technologies and virtual reality techniques, which are a base of the so-called hybrid prototyping.

  1. Learning control for riser-slug elimination and production-rate optimization for an offshore oil and gas production process

    DEFF Research Database (Denmark)

    Pedersen, Simon; Løhndorf, Petar Durdevic; Yang, Zhenyu

    2014-01-01

    Slugging flow in the offshore oil & gas production attracts lot of attention due to it's limitation of production rate, periodic overload on processing facilities, and even direct cause of emergency shutdown. This work aims at two correlated objectives: (i) Preventing slugging flow; and meanwhile......, (ii) maximizing the production rate at the riser of an offshore production platform, by manipulating a topside choke valve through a learning switching model-free PID controller. The results show good steady-state performance, though a long settling time due to the unknown reference for no slugging...

  2. Control Strategies for Drug Product Continuous Direct Compression-State of Control, Product Collection Strategies, and Startup/Shutdown Operations for the Production of Clinical Trial Materials and Commercial Products.

    Science.gov (United States)

    Almaya, Ahmad; De Belder, Lawrence; Meyer, Robert; Nagapudi, Karthik; Lin, Hung-Ren Homer; Leavesley, Ian; Jayanth, Jayanthy; Bajwa, Gurjit; DiNunzio, James; Tantuccio, Anthony; Blackwood, Dan; Abebe, Admassu

    2017-04-01

    Continuous manufacturing (CM) has emerged in the pharmaceutical industry as a paradigm shift with significant advantages related to cost, efficiency, flexibility, and higher assurance of quality. The inherent differences from batch processes justify examining the CM control strategy more holistically. This article describes the current thinking for the control and implementation of CM, using the example of a direct compression process and taking into consideration the ICH Q10 definition of "state of control" and process validation requirements. Statistical process control using control charts, sources of variation, process capability, and process performance is explained as a useful concept that can help assess the impact of variation within a batch and indicates if a process is in state of control. The potential for time-variant nature of startup and shutdown with CM is discussed to assure product quality while minimizing waste as well as different options for detection and isolation of non-conforming materials due to process upsets. While different levels of control are possible with CM, an appropriate balance between process control and end product testing is needed depending on the level of process understanding at the different stages of development from the production of clinical supplies through commercialization.

  3. JUSTIFICATION OF TEMPERATURE CONTROL FOR PRODUCTION SUPPOSITORIES WITH GLIFAZIN

    Directory of Open Access Journals (Sweden)

    Dmitrievskiy D.I.

    2015-05-01

    Full Text Available The intensive search for new anti-diabetic drugs, carried out in the National pharmaceutical university in recent years led to the creation of complex drug "Glifazin" on base of which the composition and technology of suppositories with hypoglycemic effect were developed. Now comprehensive physicochemical and pharmacological study of the dosage form are going on. This paper presents results of determining the critical parameters of technology of suppositories witn Glifazin produced by molding - temperature control of homogenization and molding of suppository mass. This mode, as shown in the work, grounded on the analysis of rheological behavior of the system in the temperature range in which it is the transition from the liquid state of Newtonian type flow to the plastic-bound state of non- Newtonian flow type. This interval for suppository mass with Glifazin is in the range 45-60 ° C. Materials and methods. As the object of the study the suppositories with Glifazin 0.1 g and polietylenoxide base on which they are prepared were taken. The study of structural and mechanical (rheological properties of suppository base and suppository mass were performed on a rotary viscometer «Reotest-2" (Germany with coaxial cylinders and the temperature range 45-60 °C. Determination of hardening temperature, resistance of suppositories to decay and their dissolution time were measured by methods of the State Pharmacopoeia of Ukraine. Determination of uniformity suppository mass was assessed by quantitative content of Glifazin in selected samples by using UV spectrophotometry method at 271 nm against a standard sample of Onozid. Results and discussion. The analysis of rheogram shows that the suppository mass with Glifazin in the test temperature range has falseplastice type of flow. The presence of hysteresis loops indicates that this system has dispersed thixotropic properties. Thus, an increase in temperature leads to a decrease in the area of the hysteresis

  4. A methodology for controlling dispersion in food production and distribution

    DEFF Research Database (Denmark)

    Rong, Aiying; Grunow, Martin

    2010-01-01

    A number of food safety crises, the design and implementation of traceability systems became an important tool for managing safety risks in the food industry. In the literature, numerous studies deal with traceability from the viewpoint of the information system and technology development. However....../customers, and logistics efforts connected to solving the safety problem. In this paper we are developing a production and distribution planning model for food supply chains to address these issues. We also present heuristics for solving the resulting mixed-integer linear programming model and demonstrate......, traceability and its implications for food safety receive less attention in literature on production and distribution planning. From the viewpoint of operations management, an efficient management of food safety risks requires the consideration of the amounts of potentially recalled products, affected regions...

  5. Utilization of biodiesel by-products for mosquito control.

    Science.gov (United States)

    Pant, Megha; Sharma, Satyawati; Dubey, Saurabh; Naik, Satya Narayan; Patanjali, Phool Kumar

    2016-03-01

    The current paper has elaborated the efficient utilization of non-edible oil seed cakes (NEOC), by-products of the bio-diesel extraction process to develop a herbal and novel mosquitocidal composition against the Aedes aegypti larvae. The composition consisted of botanical active ingredients, inerts, burning agents and preservatives; where the botanical active ingredients were karanja (Pongamia glabra) cake powder and jatropha (Jatropha curcas) cake powder, products left after the extraction of oil from karanja and jatropha seed. The percentage mortality value recorded for the combination with concentration, karanja cake powder (20%) and jatropha cake powder (20%), 1:1 was 96%. The coil formulations developed from these biodiesel by-products are of low cost, environmentally friendly and are less toxic than the synthetic active ingredients.

  6. DISTRIBUTED ELECTRICAL POWER PRODUCTION SYSTEM AND METHOD OF CONTROL THEREOF

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a distributed electrical power production system wherein two or more electrical power units comprise respective sets of power supply attributes. Each set of power supply attributes is associated with a dynamic operating state of a particular electrical power unit....

  7. Electrical Production and Pollution Control. Environmental Education Curriculum.

    Science.gov (United States)

    Topeka Public Schools, KS.

    Citizen use of our nation's industrial products has led to increased pollution problems and demand for diminishing energy reserves. In an attempt to encourage intelligent cooperation among science, industry, government and all citizens, this unit was developed to introduce secondary science students to the many facets of the electrical production…

  8. Lactide Synthesis and Chirality Control for Polylactic acid Production.

    Science.gov (United States)

    Van Wouwe, Pieter; Dusselier, Michiel; Vanleeuw, Evelien; Sels, Bert

    2016-05-10

    Polylactic acid (PLA) is a very promising biodegradable, renewable, and biocompatible polymer. Aside from its production, its application field is also increasing, with use not only in commodity applications but also as durables and in biomedicine. In the current PLA production scheme, the most expensive part is not the polymerization itself but obtaining the building blocks lactic acid (LA) and lactide, the actual cyclic monomer for polymerization. Although the synthesis of LA and the polymerization have been studied systematically, reports of lactide synthesis are scarce. Most lactide synthesis methods are described in patent literature, and current energy-intensive, aselective industrial processes are based on archaic scientific literature. This Review, therefore, highlights new methods with a technical comparison and description of the different approaches. Water-removal methodologies are compared, as this is a crucial factor in PLA production. Apart from the synthesis of lactide, this Review also emphasizes the use of chemically produced racemic lactic acid (esters) as a starting point in the PLA production scheme. Stereochemically tailored PLA can be produced according to such a strategy, giving access to various polymer properties.

  9. Metabolic Design and Control for Production in Prokaryotes

    Energy Technology Data Exchange (ETDEWEB)

    Chhabra, Swapnil R.; Keasling, J.D.

    2010-11-10

    Prokaryotic life on earth is manifested by its diversity and omnipresence. These microbes serve as natural sources of a large variety of compounds with the potential to serve the ever growing, medicinal, chemical and transportation needs of the human population. However, commercially viable production of these compounds can be realized only through significant improvement of the native production capacity of natural isolates. The most favorable way to achieve this goal is through the genetic manipulation of metabolic pathways that direct the production of these molecules. While random mutagenesis and screening have dominated the industrial production of such compounds in the past our increased understanding of microbial physiology over the last five decades has shifted this trend towards rational approaches for metabolic design. Major drivers of this trend include recombinant DNA technology, high throughput characterization of macromolecular cellular components, quantitative modeling for metabolic engine ring, targeted combinatorial engineering and synthetic biology. In this chapter we track the evolution of microbial engineering technologies from the black box era of random mutagenesis to the science and engineering-driven era of metabolic design.

  10. The availability and use of chemotherapeutic sea lice control products

    NARCIS (Netherlands)

    Roth, Myron

    2000-01-01

    An international survey revealed that eleven compounds representing five pesticide types are currently being used on commercial salmon farms for sea lice control. These include two organophosphates (dichlorvos and azamethiphos); three pyrethrin/pyrethroid compounds (pyrethrum, cypermethrin, deltamet

  11. Waves of fashion : The consuming production of management control

    OpenAIRE

    Backlund Björke, Andreas

    2011-01-01

    The responsiveness of organizational leaders regarding suggestions related to various managerial techniques has led to the coinage of the ‘management fashion’ idiom. It has been convincingly argued that phenomena like management control systems are prone to trends, and that such trends permeate into the daily life of managers through the use of persuasive rhetoric. This thesis is a theory-generating study of change in management control systems. More precisely, its purpose is to seek an under...

  12. Controls on sediment production in two U.S. deserts

    Science.gov (United States)

    Belnap, Jayne; Walker, Beau J.; Munson, Seth M.; Gill, Richard A.

    2014-01-01

    Much of the world’s airborne sediment originates from dryland regions. Soil surface disturbances in these regions are ever-increasing due to human activities such as energy and mineral exploration and development, recreation, suburbanization, livestock grazing and cropping. Sediment production can have significant impacts to human health with particles potentially carrying viruses such as Valley Fever or causing asthma or other respiratory diseases. Dust storms can cause decreased visibility at the ground level, resulting in highway accidents, and reduced visual quality in park and wildland airsheds. Sediment production and deposition is also detrimental to ecosystem health, as production reduces soil fertility at its source and can bury plants and other organisms where it is deposited. Therefore, it is important to understand how we can predict what areas are prone to producing sediment emissions both before and after soil surface disturbance. We visited 87 sites in two deserts of the western U.S. that represented a range of soil texture and surface cover types. We used a portable wind tunnel to estimate the threshold friction velocity (TFV) required to initiate sediment transport and the amount of sediment produced by the tunnel at a set wind speed. Wind tunnel runs were done before and after soil surface disturbance with a four-wheel drive vehicle. Results show that most undisturbed desert soils are very stable, especially if covered by rocks or well-developed biological soil crusts, which make them virtually wind-erosion proof. Particles at disturbed sites, in contrast, moved at relatively low wind speeds and produced high amounts of sediment. Silt was an important predictor of TFV and sediment production across all sites, whereas the influence of rock cover and biological soil crusts was site-dependent. Understanding the vulnerability of a site after disturbance is important information for land managers as they plan land use activities and attempt to

  13. 21 CFR 111.60 - What are the design requirements for the production and process control system?

    Science.gov (United States)

    2010-04-01

    ... production and process control system? 111.60 Section 111.60 Food and Drugs FOOD AND DRUG ADMINISTRATION... to Establish a Production and Process Control System § 111.60 What are the design requirements for the production and process control system? (a) Your production and in-process control system must...

  14. Changing Quality Controls: The Effects of Increasing Product Variety and Shortening Product Life Cycles

    NARCIS (Netherlands)

    J.D. van Iwaarden (Jos)

    2006-01-01

    textabstractIn many industries (e.g. cars, electronics, clothing) manufacturing complexity and unpredictability have increased in recent years because of increasing product variety and shortening product life cycles. At the same time, manufacturers in these industries appear to have more problems wi

  15. 40 CFR 112.9 - Spill Prevention, Control, and Countermeasure Plan Requirements for onshore oil production...

    Science.gov (United States)

    2010-07-01

    ... signal to the computer where the facility is subject to a computer production control system. (5) Flow... 40 Protection of Environment 21 2010-07-01 2010-07-01 false Spill Prevention, Control, and Countermeasure Plan Requirements for onshore oil production facilities (excluding drilling and...

  16. 22 CFR 62.71 - Control and production of the electronic Form DS-2019.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Control and production of the electronic Form... EXCHANGE VISITOR PROGRAM Student and Exchange Visitor Information System (SEVIS) § 62.71 Control and production of the electronic Form DS-2019. (a) SEVIS generated Forms DS-2019 shall only be completed,...

  17. 7 CFR 1424.10 - Succession and control of facilities and production.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Succession and control of facilities and production... § 1424.10 Succession and control of facilities and production. A person who obtains a facility that is... may terminate a contract and demand full refund of payments made if a contracting party loses...

  18. Bernoulli serial production lines with quality control devices: theory and application

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available This paper develops the procedure for the analysis of the production systems with quality control devices. The evaluation of the production system requires an expression for the system performance measures as functions of the machine and buffer parameters. This paper presents a method for evaluating these functions and illustrates their practical utility using a case study at a production plant.

  19. Performance Analysis of a Manufacturing Line Operated under Optimal Surplus-Based Production Control

    Directory of Open Access Journals (Sweden)

    K. K. Starkov

    2012-01-01

    Full Text Available We examine optimality and performance of a tandem manufacturing line driven by a surplus-based decentralized production control strategy. The main objective of this type of production strategies is to guarantee that the cumulative number of produced products follows the cumulative production demand on the output of the given network. The basic idea of surplus-based control strategy is presented for the case of one manufacturing machine. We prove that this strategy is optimal. Then, a flow model of a line composed of arbitrarily many machines with bounded buffers is analyzed. We prove that the surplus-based production control enables this network to efficiently follow the product demand and establish the relation between the efficiency in the production tracking error and the intermediate inventory levels of a line. Performance and robustness of the flow model of the closed-loop manufacturing line are illustrated by computer simulations.

  20. Histamine poisoning and control measures in fish and fishery products

    Directory of Open Access Journals (Sweden)

    Pierina eVisciano

    2014-09-01

    Full Text Available Histamine poisoning is one of the most common form of intoxication caused by the ingestion of fish and fishery products. Cooking, canning or freezing cannot reduce the levels of histamine because this compound is heat stable. All humans are susceptible to histamine and its effects can be described as intolerance or intoxication depending on the severity of the symptoms. The amount of histamine in food, the individual sensitivity and the detoxification activity in human organism represent the main factors affecting the toxicological response in consumers. Histamine is the only biogenic amine with regulatory limits set by European Legislation, up to a maximum of 200 mg/kg in fresh fish and 400 mg/kg in fishery products treated by enzyme maturation in brine.

  1. A high-performance liquid chromatography with circular dichroism detector for determination of stereochemistry of 6, 9-oxygen bridge dibenzocyclooctadiene lignans from kadsura coccinea.

    Science.gov (United States)

    Zhu, Hui; Xu, Liang; Yang, Shi-Lin; Li, He-Ran

    2015-10-01

    The stereochemistry of two 6, 9-oxygen bridge dibenzocyclooctadiene lignans from Kadsura coccinea, are difficult to separate and very unstable. The present study was designed to develop a high-performance liquid chromatography using circular dichroism detection for the analysis of the stereochemistry. A new 6, 9-oxygen bridge dibenzocyclooctadiene lignans named Kadsulignan Q was firstly found with an S-biphenyl configuration. The other compound was identified as Kadsulignan L with an R- biphenyl configuration. In order to obtain kinetic data on their reversible interconversion, the stability was measured at different deuterated solvents such as deuterated methanol, deuterated chloroform and deuterated dimethylsulfoxide. The lignans were more unstable and converted more easily in deuterated methanol than in deuterated chloroform and deuterated dimethylsulfoxide.

  2. Computational and NMR Spectroscopic Evidence for Stereochemistry-Dependent Conformations of 2,2,6,6-Tetramethylpiperidinyl-Masked 1,2-Diols.

    Science.gov (United States)

    Fought, Ellie L; Chatterjee, Shreyosree; Windus, Theresa L; Chen, Jason S

    2015-10-16

    2,2,6,6-Tetramethylpiperidinyl-masked 1,2-diols exhibited stereochemistry-dependent hydroxyl proton chemical shifts: ca. 7 ppm for the syn diastereomer and ca. 2 ppm for the anti diastereomer. A computational search for low energy geometries revealed that the syn isomer favors a six-membered ring hydrogen bond to nitrogen and the anti isomer favors a five-membered ring hydrogen bond to oxygen. The computed low energy conformations were found to have a large difference in hydroxyl proton shielding that was reflected in the experimental chemical shift difference. This chemical shift difference was observed in a broad range of solvents, and thus may be useful as a stereochemical probe. The stereochemistry-dependent conformation and chemical shift signature appeared to be due to a syn pentane interaction between the gem-dimethyl groups on the 2,2,6,6-tetramethylpiperidinyl moiety.

  3. Microbial Gas Production Used to Achieve Autonomous Buoyancy Control

    Science.gov (United States)

    2010-09-01

    counter weight. The microbe used is cultured in the Erlenmeyer flask. Clostridium acetobutylicum for micro1bial ballast In order to utilize microbial...34 20 0 --100% 0 20 40 60 80 Time(hr) Figure 6. Gas production by different S()lid-phase agar cultures of C. acetobutvlicum. Clostridium ... acetobutylicum as our model microbe; a gram-positive anaerobic bacterium known for its ability to produce hydrogen gas 4,5 To determine if there

  4. Subsystem for control of isotope production with linear electron accelerator

    CERN Document Server

    Karasyov, S P; Uvarov, V L

    2001-01-01

    In this report the high-current LINAC subsystem for diagnostic and monitoring the basic technological parameters of isotope production (energy flux of Bremsstrahlung photons and absorbed doze in the target,target activity, temperature and consumption of water cooling the converter and target) is described.T he parallel printer port (LPT) of the personal computer is proposed to use as an interface with the measurement channels.

  5. Chemical and mechanical control of corrosion product transport

    Energy Technology Data Exchange (ETDEWEB)

    Hede Larsen, O.; Blum, R. [I/S Fynsvaerket, Faelleskemikerne, Odense (Denmark); Daucik, K. [I/S Skaerbaekvaerket, Faelleskemikerne, Fredericia (Denmark)

    1996-12-01

    The corrosion products formed in the condensate and feedwater system of once-through boilers are precipitated and deposited inside the evaporator tubes mainly in the burner zone at the highest heat flux. Depositions lead to increased oxidation rate and increased metal temperature of the evaporator tubes, hereby decreasing tube lifetime. This effect is more important in the new high efficiency USC boilers due to increased feedwater temperature and hence higher thermal load on the evaporator tubes. The only way to reduce the load on the evaporator tubes is to minimise corrosion product transport to the boiler. Two general methods for minimising corrosion product transport to the boiler have been evaluated through measurement campaigns for Fe in the water/steam cycle in supercritical boilers within the ELSAM area. One method is to reduce corrosion in the low temperature condensate system by changing conditioning mode from alkaline volatile treatment (AVT) to oxygenated treatment (OT). The other method is to filtrate part of the condensate with a mechanical filter at the deaerator. The results show, that both methods are effective at minimising Fe-transport to the boiler, but changing to OT has the highest effect and should always be used, whenever high purity condensate is maintained. Whether mechanical filtration also is required, depends on the boiler, specifically the load on the evaporator. A simplified calculation model for lifetime evaluation of evaporator tubes has been developed. This model has been used for evaluating the effect of corrosion product transport to the boiler on evaporator tube lifetime. Conventional supercritical boilers generally can achieve sufficient lifetime by AVT and even better by OT, whereas all measures to reduce Fe-content of feedwater, including OT and mechanical filtration, should be taken, to ensure sufficient lifetime for the new boilers with advanced steam data - 290 bar/580 deg. C and above. (au)

  6. Well productivity controlling factors in crystalline terrains of southeastern Brazil

    Science.gov (United States)

    Neves, Mirna A.; Morales, Norberto

    2007-05-01

    Over the last decades, increasing water demands have fostered research to obtain high well yields in crystalline terrains where, besides the intrinsic properties of rocks, the groundwater flow depends on several factors. The depth of the wells, the lithotypes, the presence and thickness of sedimentary coverings and weathered layers, the landforms, the geological structures, and the effects of tectonic stresses are among the most investigated factors considered as determinant of well productivity. The influence of these factors on productivity of wells that exploit the Crystalline Aquifer System in the Jundiaí River Catchment, southeastern Brazil, is investigated in this work. The largest region of the studied area is located on the Precambrian Basement, partially covered by sedimentary deposits. The results show that the sedimentary deposits and the weathered layer are important for high well yield, but it also depends on the existence of a net of open fractures, in order to maintain high productivity. The sites that have more possibility of occurrence of such structures are the regional shear and fault zones and other minor structures with NW-SE and E-W directions, which characterize areas subjected to transtensional stress related to the neotectonics.

  7. Modeling, simulation, and control of an extraterrestrial oxygen production plant

    Science.gov (United States)

    Schooley, L.; Cellier, F.; Zeigler, B.; Doser, A.; Farrenkopf, G.

    1991-01-01

    The immediate objective is the development of a new methodology for simulation of process plants used to produce oxygen and/or other useful materials from local planetary resources. Computer communication, artificial intelligence, smart sensors, and distributed control algorithms are being developed and implemented so that the simulation or an actual plant can be controlled from a remote location. The ultimate result of this research will provide the capability for teleoperation of such process plants which may be located on Mars, Luna, an asteroid, or other objects in space. A very useful near-term result will be the creation of an interactive design tool, which can be used to create and optimize the process/plant design and the control strategy. This will also provide a vivid, graphic demonstration mechanism to convey the results of other researchers to the sponsor.

  8. The Robust H∞ Control of a Stochastic Inventory-Production System

    Institute of Scientific and Technical Information of China (English)

    ZHONG Mai-ying; TANG Bing-yong

    2002-01-01

    Considering both the stochastic demand rate and norm-bounded unknown demand uncertainty,this paper deals with the inventory-production control problem where the stocked products may deteriorate with a rate that depends on the stochastic demand rate. By using robust H∞ control technique, the existing conditions of state feedback control strategies is given and proved, and the robust optimal policy that solves this problem is obtained in terms of a set of linear matrix inequality (LMI). Finally, an example illustrates the usefulness of the proposed methods and shows that robust H∞ control inventory-production strategy could attenuate the influence of demand uncertainty more efficiently than linear quadratic optimal policy.

  9. Methods of detecting and controlling mucoid Pseudomonas biofilm production

    Science.gov (United States)

    Yu, Hongwei D. (Inventor); Qiu, Dongru (Inventor)

    2013-01-01

    Compositions and methods for detecting and controlling the conversion to mucoidy in Pseudomonas aeruginosa are disclosed. The present invention provides for detecting the switch from nonmucoid to mucoid state of P. aeruginosa by measuring mucE expression or MucE protein levels. The interaction between MucE and AlgW controls the switch to mucoidy in wild type P. aeruginosa. Also disclosed is an alginate biosynthesis heterologous expression system for use in screening candidate substances that inhibit conversion to mucoidy.

  10. Use of NOESYTP in stereochemistry determination of anew limonoid from Khaya senegalensis; Aplicacao de NOESYTP na determinacao da estereoquimica de um novo limonoide de khaya senegalensis

    Energy Technology Data Exchange (ETDEWEB)

    Salles, Lis Regina V.O.; Silva, M. Fatima das G.F. da; Rodrigues Filho, Edson; Fernandes, Joao Batista; Vieira, Paulo C. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

    1995-12-31

    This work has dealt with the phyto chemical study of Kaya senegalensis. From the stem of Khaya senegalensis was isolated one novel limonoid, which was acetylated prior to analysis. Nuclear magnetic resonance techniques have been used to characterize and identify the compound and elucidate its stereochemistry. The placement of substituents at C-30{beta} and C-14{alpha} were established by NOESYTP experiments 5 refs., 4 tabs.

  11. Applications of natural products in the control of mosquito ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-12-29

    Dec 29, 2009 ... resistance evolution (see below), this may not always be the case. ... Although new syn- thetic chemicals have not ... Biological control of mosquito larvae has been mana- ged through ... while relatively non-toxic to the surrounding environment. .... over-expression of certain of these genes in highly resistant ...

  12. Design and control of integrated styrene aniline production plant

    NARCIS (Netherlands)

    Partenie, O.; Van der Last, V.; Sorin Bildea, C.; Altimari, P.

    2009-01-01

    This paper illustrates the operational difficulties arising from simultaneously performing exothermic and endothermic reactions, and demonstrates that a plant can be built and safely operated by integrating the design and plantwide control issues. The behaviour of reactor – separation – recycle

  13. USDA Mosquito Control Product Research for the US Military

    Science.gov (United States)

    New techniques that were developed at the USDA to protect deployed military troops from the threat of vector-borne diseases and are also applicable for use by civilian mosquito control program use are described. Techniques to be illustrated include: (1) novel military personal protection methods, (2...

  14. Fault tolerant wind turbine production operation and shutdown (Sustainable Control)

    NARCIS (Netherlands)

    Van Engelen, T.; Schuurmans, J.; Kanev, S.; Dong, J.; Verhaegen, M.H.G.; Hayashi, Y.

    2011-01-01

    Extreme environmental conditions as well as system failure are real-life phenomena. Especially offshore, extreme environmental conditions and system faults are to be dealt with in an effective way. The project Sustainable Control, a new approach to operate wind turbines (Agentschap NL, grant EOSLT02

  15. Bacillus thuringiensis-based Products for Insect Pest Control

    NARCIS (Netherlands)

    Maagd, de R.A.

    2015-01-01

    Bacillus thuringiensis (or Bt, as it has become generally known) is one of the oldest and widely used biological control agents and has a long history of use. Bt and a number of related bacteria produce a variety of toxins, mostly—but not exclusively- localized in the parasporal crystals, which are,

  16. Aspects of the Control and Production of Speech.

    Science.gov (United States)

    Ohala, John J.

    The dominant trend in phonetics today--due to a large extent to generative phonology--is to discover the brain mechanisms underlying the observed behavior in speech. Among other things there is interest in attempting to find out how motor programs are stored latently, selected, activated into muscular contractions, controlled, and tailored for…

  17. Use of statistical process control in the production of blood components

    DEFF Research Database (Denmark)

    Magnussen, K.; Quere, S.; Winkel, P.

    2008-01-01

    occasional component manufacturing staff to an experienced regular manufacturing staff. Production of blood products is a semi-automated process in which the manual steps may be difficult to control. This study was performed in an ongoing effort to improve the control and optimize the quality of the blood...... components produced and gives an example of how to meet EU legislative requirements in a small-scale production centre. Data included quality control measurements in 363 units of red blood cells, 79 units of platelets produced by an occasional staff with 11 technologists and 79 units of platelets produced...... staff were out of control, which was not the case with the experienced staff. Introduction of control charts to a small blood centre has elucidated the difficulties in controlling the blood production and shown the advantage of using experienced regular component manufacturing staff Udgivelsesdato: 2008/6...

  18. Sensorimotor control of vocal pitch production in Parkinson's disease.

    Science.gov (United States)

    Chen, Xi; Zhu, Xiaoxia; Wang, Emily Q; Chen, Ling; Li, Weifeng; Chen, Zhaocong; Liu, Hanjun

    2013-08-21

    The present study was designed to investigate the sensorimotor control of voice fundamental frequency (F0) in individuals with Parkinson's diseases (PD). Fifteen Cantonese individuals with PD, and fifteen age- and sex-matched healthy Cantonese individuals participated in the experiment. Participants were asked to vocalize a vowel sound while hearing their voice auditory feedback unexpectedly pitch-shifted upwards or downwards through headphones. The size of pitch shifts varied from 50, 100, to 200 cents. One novel averaging method was used to categorize the individual trials such that only those trials that opposed the perturbation direction were averaged to generate an overall response. The results showed that Cantonese individuals with PD produced significantly larger magnitudes of vocal compensation for pitch perturbations than healthy participants. Both groups showed systematic changes in compensation magnitude as a function of perturbation size and direction: larger perturbation size or upward direction elicited greater compensation magnitude. Moreover, pitch variability indexed by the standard deviations of the baseline F0 was significantly correlated with the magnitude of vocal compensation in individuals with PD, whereas this correlation failed to reach significance for healthy participants. This study presents the first data demonstrating the abnormal processing of auditory feedback in the sensorimotor control of voice F0 for Cantonese individuals with PD. It is suggested that the abnormal sensorimotor integration of voice F0 control in PD may be caused by the increased weighting of auditory feedback control resulting from dysfunction of feedforward control and somatosensory feedback caused by the impairment of the basal ganglia. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Optimization of Monacolin Production in a Controlled System

    Directory of Open Access Journals (Sweden)

    Shafieh Mansoori

    2015-10-01

    Full Text Available Monascus purpureus is a fungus that had been cultured on the rice in eastern Asian countries from thousand years ago and used as a food for long years. The fungus produces very valuable metabolites with polyketide structure. The most of important metabolite is Monacolin K, Lovastatin or competitive inhibitor of HMG-CoA reductase (an affective enzyme in cholesterol synthesis. This metabolite have properties including reducing blood cholesterol, treatment of progressive renal disease, the potential for treat a variety of tumors, preventing infection, vascular diseases and bone fractures. In this study, Monascus purpureus PTCC5303 has been used for lovastatin production in liquid fermentation. The nutritional concentration that were significant in biomass and lovastatin production included maltose and MgSO4, were optimized by Response Surface Methodology (RSM in a milibioreactor. The optimum concentration of maltose and MgSO4 wereobtained 10 g/L and 0.78 g/L, respectively. According to our results, maximum lovastatin production under optimum condition containing maltose 10 g/L, peptone 5 g/L, MgSO4.7H2O 0.78 g/L, MnSO4.H2O 0.5 g/L, KH2PO4 4 g/L, thiamine 0.1 g/L, and pH=7 at 30°C, 130 rpm and flow rate 1.8 L/min was obtained to be 309 µg l−1 after 10 days of fermentation period.

  20. PRICING POLICY‟ CONTROL AT THE ELECTRICITY PRODUCTION SECTOR

    Directory of Open Access Journals (Sweden)

    Zamira Anvarovna Daudova

    2014-01-01

    Full Text Available The paper considered one of the most important indica-tors characterizing the state of affairs at the electric pow-er sector, i.e. the price set for heat and electricity supply. The rate should stay at a moderate level. However, the rates have been steadily increasing nowadays. The paper gave a description of the price setting machinery in the electric power sector, with the ways capable of enhanc-ing efficiency in price making. The study suggested that the per capita consumption should be shortened round the country, in order to fix the rate of consumption per person that further would entail the rate‟ decrease in the tariffs for heat and electricity supply.Producing heat and electricity at the combined heat and power plant (CHPP in most cases has proven to be more efficient than the separate stations; that is why great attention was given now to developing approaches to breakdown the production cost for heat and electricity in the combined production figures. Efficient application of the combined production of heat and electric power should outline the prices and tariffs understandable by reasons of technology and economy being set for both types of energy, while keeping production profitable for both the separate and combined schemes. During transi-tion to adjusted tariffs under the RAB technique (proce-dure, a company shall start earning income exactly re-ferred to their cost of setting up assets. The effective rate figure should not exceed the limits acceptable that should be consistent with the regional executive power authority representing public interests and consumers at the region. For checking properly networks‟ operational reliability in computing tariffs for electricity supply under RAB technique, the provider should regularly refer (at least once in three years to the study outcomes concern-ing the rate correlation with increase in reliability of net-works (to the optimal level, with the adjustments made to investment programs

  1. Multi-assortment rhythmic production planning and control

    Science.gov (United States)

    Skolud, B.; Krenczyk, D.; Zemczak, M.

    2015-11-01

    A method for production planning in a repetitive manufacturing system which allows for estimating the possibility of processing work orders in due time is presented. The difference between two approaches are presented; the first one one-piece flow elaborated in Toyota and the second one elaborated by authors that consists in defining sufficient conditions to filter all solutions and providing a set of admissible solutions for both the client and the producer. In the paper attention is focused on the buffer allocation. Illustrative examples are presented.

  2. Holistic indices for productivity control assessment, applied to the comparative analysis of PID and fuzzy controllers within an Isasmelt furnace

    OpenAIRE

    Ojeda Sarmiento, Juan Manuel; Fuertes Armengol, José Mª; Griful Ponsati, Eulàlia

    2014-01-01

    This research aims to contribute to the analysis of control performance assessment in extractive metallurgy. Productivity-based indices are proposed in addition to current measuring techniques. Such criteria are employed to compare conventional PID and fuzzy-based controllers in copper smelting. This process is mathematically modeled in order to be simulated. The comparison confirms a better performance of the fuzzy controller in dealing with the molten bath temperature within an Isasmelt fur...

  3. Arcmon for Process Control in Silicomanganese Production: A Case Study

    Science.gov (United States)

    Steenkamp, Joalet Dalene; Hockaday, Christopher James; Gous, Johan Petrus; Clark, Wilma; Corfield, Archie

    2017-08-01

    Arcmon is a device that is used to quantify the amount of arcing (expressed as arc power fraction) that takes place in submerged-arc furnaces (SAFs). During a trial installation on a 48-MVA SAF used for the production of SiMn, differences in arcing behavior between the three different electrodes were observed, with the amount of arcing on one electrode being significantly higher than on the other two. During the subsequent excavation of the SAF, the increased amount of arcing had been attributed to the presence of a hard build-up below the electrode. Phase chemical analysis of the hard build-up indicated that it consisted primarily of portlandite (a reaction product of calcium carbide that probably reacted with the water used to cool down the burden during excavation) and silicon carbide. In comparison, the coke-bed below one of the other electrodes consisted mainly of graphite, silicon carbide, and phases which will typically precipitate from slag upon cooling, i.e. phases expected to be present in a coke-bed. The presence of such a large build-up of carbide material is undesirable as it effectively reduces the volume of coke-bed available for the reduction reactions to occur. The study indicated that Arcmon could potentially be applied as an early warning system to identify the presence of such a build-up.

  4. Independent controls for neocortical neuron production and histogenetic cell death

    Science.gov (United States)

    Verney, C.; Takahashi, T.; Bhide, P. G.; Nowakowski, R. S.; Caviness, V. S. Jr

    2000-01-01

    We estimated the proportion of cells eliminated by histogenetic cell death during the first 2 postnatal weeks in areas 1, 3 and 40 of the mouse parietal neocortex. For each layer and for the subcortical white matter in each neocortical area, the number of dying cells per mm(2) was calculated and the proportionate cell death for each day of the 2-week interval was estimated. The data show that cell death proceeds essentially uniformly across the neocortical areas and layers and that it does not follow either the spatiotemporal gradient of cell cycle progression in the pseudostratified ventricular epithelium of the cerebral wall, the source of neocortical neurons, or the 'inside-out' neocortical neuronogenetic sequence. Therefore, we infer that the control mechanisms of neocortical histogenetic cell death are independent of mechanisms controlling neuronogenesis or neuronal migration but may be associated with the ingrowth, expansion and a system-wide matching of neuronal connectivity. Copyright 2000 S. Karger AG, Basel.

  5. Production of spin-controlled rare isotope beams

    CERN Document Server

    Ichikawa, Y; Ishii, Y; Furukawa, T; Yoshimi, A; Kameda, D; Watanabe, H; Aoi, N; Asahi, K; Balabanski, D L; Chevrier, R; Daugas, J M; Fukuda, N; Georgiev, G; Hayashi, H; Iijima, H; Inabe, N; Inoue, T; Ishihara, M; Kubo, T; Nanao, T; Ohnishi, T; Suzuki, K; Tsuchiya, M; Takeda, H; Rajabali, M M

    2012-01-01

    The degree of freedom of spin in quantum systems serves as an unparalleled laboratory where intriguing quantum physical properties can be observed, and the ability to control spin is a powerful tool in physics research. We propose a novel method for controlling spin in a system of rare isotopes which takes advantage of the mechanism of the projectile fragmentation reaction combined with the momentum-dispersion matching technique. The present method was verified in an experiment at the RIKEN RI Beam Factory, in which a degree of alignment of 8% was achieved for the spin of a rare isotope Al-32. The figure of merit for the present method was found to be greater than that of the conventional method by a factor of more than 50.

  6. Superfast vocal muscles control song production in songbirds.

    Directory of Open Access Journals (Sweden)

    Coen P H Elemans

    Full Text Available Birdsong is a widely used model for vocal learning and human speech, which exhibits high temporal and acoustic diversity. Rapid acoustic modulations are thought to arise from the vocal organ, the syrinx, by passive interactions between the two independent sound generators or intrinsic nonlinear dynamics of sound generating structures. Additionally, direct neuromuscular control could produce such rapid and precisely timed acoustic features if syringeal muscles exhibit rare superfast muscle contractile kinetics. However, no direct evidence exists that avian vocal muscles can produce modulations at such high rates. Here, we show that 1 syringeal muscles are active in phase with sound modulations during song over 200 Hz, 2 direct stimulation of the muscles in situ produces sound modulations at the frequency observed during singing, and that 3 syringeal muscles produce mechanical work at the required frequencies and up to 250 Hz in vitro. The twitch kinematics of these so-called superfast muscles are the fastest measured in any vertebrate muscle. Superfast vocal muscles enable birds to directly control the generation of many observed rapid acoustic changes and to actuate the millisecond precision of neural activity into precise temporal vocal control. Furthermore, birds now join the list of vertebrate classes in which superfast muscle kinetics evolved independently for acoustic communication.

  7. Control of VTEC in Dutch livestock and meat production.

    Science.gov (United States)

    Reinders, R D; Weber, M F; Lipman, L J; Verhoeff, J; Bijker, P G

    2001-05-21

    The Dutch government and the meat industry, recognising VTEC as having important public health, meat quality and economic implications, have taken a number of initiatives within the last 5 years to control VTEC in livestock and meat. These initiatives, brought together last year in a 'Masterplan VTEC', include short-, middle- and long-term priorities. Short-term priorities include advice on interventions in the cases of an outbreak of VTEC associated with a cattle herd, the implementation of handbooks for Good Manufacturing Practice (GMP) in slaughterhouses and deboning plants, and the execution of an action programme on zero-tolerance to faecal contamination of carcasses. Mid-term activities include surveillance of the occurrence of VTEC and other enteropathogens in livestock and meat, and the investigations of VTEC population dynamics in dairy farms, transportation and farm hygiene. In the longer term, this programme aims to produce a system of Integrated Quality Assurance, consolidating effective measures to control VTEC in Dutch livestock and meat, and integrating emerging means for control and prevention.

  8. The isolation, total synthesis and structure elucidation of chlorofusin, a natural product inhibitor of the p53-MDM2 protein-protein interaction

    Science.gov (United States)

    Clark, Ryan C.; Lee, Sang Yeul; Searcey, Mark; Boger, Dale L.

    2009-01-01

    Inhibitors of key protein-protein interactions are emerging as exciting therapeutic targets for the treatment of cancer. One such interaction between MDM2 (HDM2) and p53, that silences the tumour suppression activities of p53, was found to be inhibited by the recently isolated natural product chlorofusin. Synthetic studies on this complex natural product summarized herein have served to reassign its chromophore relative stereochemistry, assign its absolute stereochemistry, and provided access to a series of key analogues and partial structures for biological evaluation. PMID:19642417

  9. PLC based automatic control of pasteurize mix in ice cream production

    Science.gov (United States)

    Yao, Xudong; Liang, Kai

    2013-03-01

    This paper describes the automatic control device of pasteurized mix in the ice cream production process.We design a scheme of control system using FBD program language and develop the programmer in the STEP 7-Micro/WIN software, check for any bugs before downloading into PLC .These developed devices will able to provide flexibility and accuracy to control the step of pasteurized mix. The operator just Input the duration and temperature of pasteurized mix through control panel. All the steps will finish automatically without any intervention in a preprogrammed sequence stored in programmable logic controller (PLC). With the help of this equipment we not only can control the quality of ice cream for various conditions, but also can simplify the production process. This control system is inexpensive and can be widely used in ice cream production industry.

  10. Control Mechanisms in Bilingual Language Production: Neural Evidence from Language Switching Studies

    Science.gov (United States)

    Abutalebi, Jubin; Green, David

    2008-01-01

    A key question in bilingual language production research is how bilingual individuals control the use of their two languages. The psycholinguistic literature concerning language control is unresolved. It is a matter of controversy whether (a) issues to do with control are central to understanding bilingual language processing; and (b) if they are,…

  11. Lean Production Control at a High-Variety, Low-Volume Parts Manufacturer

    NARCIS (Netherlands)

    Bokhorst, Jos A. C.; Slomp, Jannes

    2010-01-01

    Eaton Electric General Supplies, a parts manufacturing unit that supplies parts for Eaton's electrical business unit, implemented several lean control elements in its high-variety, low-volume production units. These control elements include a constant work-in-process mechanism to limit and control

  12. Lean Production Control at a High-Variety, Low-Volume Parts Manufacturer

    NARCIS (Netherlands)

    Bokhorst, Jos A. C.; Slomp, Jannes

    2010-01-01

    Eaton Electric General Supplies, a parts manufacturing unit that supplies parts for Eaton's electrical business unit, implemented several lean control elements in its high-variety, low-volume production units. These control elements include a constant work-in-process mechanism to limit and control t

  13. Weed control using ammonium nonanoate and cultivation in organic Vidalia sweet onion production

    Science.gov (United States)

    Ammonium nonanoate is registered for weed control in certified organic crop production and may be useful to control cool-season weeds in organic Vidalia® sweet onion. Cultivation with a tine weeder has been identified as a cost-effective means of weed control, but delays in cultivation cause some w...

  14. Stimulating productivity of hydroponic lettuce in controlled environments with triacontanol

    Science.gov (United States)

    Knight, S. L.; Mitchell, C. A.

    1987-01-01

    Triacontanol (1-triacontanol) applied as a foliar spray at 10(-7) M to 4-day-old, hydroponically grown leaf lettuce (Lactuca sativa L.) seedlings in a controlled environment increased leaf fresh and dry weight 13% to 20% and root fresh and dry weight 13% to 24% 6 days after application, relative to plants sprayed with water. When applied at 8 as well as 4 days after seeding, triacontanol increased plant fresh and dry weight, leaf area, and mean relative growth rate 12% to 37%. There was no benefit of repeating application of triacontanol in terms of leaf dry weight gain.

  15. Cleaning the Produced Water in Offshore Oil Production by Using Plant-wide Optimal Control Strategy

    DEFF Research Database (Denmark)

    Yang, Zhenyu; Pedersen, Simon; Løhndorf, Petar Durdevic

    2014-01-01

    To clean the produced water is always a challenging critical issue in the offshore oil & gas industry. By employing the plant-wide control technology, this paper discussed the opportunity to optimize the most popular hydrocyclone-based Produced Water Treatment (PWT) system. The optimizations...... of the efficiency control of the de-oiling hydrocyclone and the water level control of the upstream separator, are discussed and formulated. Some of our latest research results on the analysis and control of slugging flows in production well-pipeline-riser systems are also presented. The ultimate objective...... of this research is to promote a technical breakthrough in the PWT control design, which can lead to the best environmental protection in the oil & gas production, without sacrificing the production capability and production costs....

  16. Improvement of inter-field CDU by using on-product focus control

    Science.gov (United States)

    Park, Kyeong Dong; Park, Tony; Hwang, Jong Hyun; Choi, Jin Phil; Kang, Young Seog

    2014-04-01

    This paper introduces to improve inter-field CDU with on-product focus control by diffraction based focus (DBF) method. For DBF target selection, a robust focus metrology for focus control was obtained, and the selected DBF target was integrated on each seven spot of a product reticle. For on-product focus control, previously on-product focus monitoring was performed, and the monitored lots showed a stable focus fingerprint. Based on the result, Z and Z/ Rx/Ry corrections per field on wafers were applied. Focus uniformity of controlled wafers was improved up to 29% in comparison with non-corrected ones. To demonstrate the improvement of inter-field CDU, Full CDs on wafers were measured by SEM. As a result, inter-field CDU for controlled wafers was improved by 16% (3σ) compared with noncontrolled wafers.

  17. From Design to Production Control Through the Integration of Engineering Data Management and Workflow Management Systems

    CERN Document Server

    Le Goff, J M; Bityukov, S; Estrella, F; Kovács, Z; Le Flour, T; Lieunard, S; McClatchey, R; Murray, S; Organtini, G; Vialle, J P; Bazan, A; Chevenier, G

    1997-01-01

    At a time when many companies are under pressure to reduce "times-to-market" the management of product information from the early stages of design through assembly to manufacture and production has become increasingly important. Similarly in the construction of high energy physics devices the collection of ( often evolving) engineering data is central to the subsequent physics analysis. Traditionally in industry design engineers have employed Engineering Data Management Systems ( also called Product Data Management Systems) to coordinate and control access to documented versions of product designs. However, these systems provide control only at the collaborative design level and are seldom used beyond design. Workflow management systems, on the other hand, are employed in industry to coordinate and support the more complex and repeatable work processes of the production environment. Commer cial workflow products cannot support the highly dynamic activities found both in the design stages of product developmen...

  18. Quality control methods for KOOS operational sea surface temperature products

    Institute of Scientific and Technical Information of China (English)

    YANG Chansu; KIM Sunhwa

    2016-01-01

    Sea surface temperature SST obtained from the initial version of the Korea Operational Oceanographic System (KOOS) SST satellite have low accuracy during summer and daytime. This is attributed to the diurnal warming effect. Error estimation of SST data must be carried out to use the real-time forecasting numerical model of the KOOS. This study suggests two quality control methods for the KOOS SST system. To minimize the diurnal warming effect, SSTs of areas where wind speed is higher than 5 m/s were used. Depending on the wind threshold value, KOOS SST data for August 2014 were reduced by 0.15°C. Errors in SST data are considered to be a combination of random, sampling, and bias errors. To estimate bias error, the standard deviation of bias between KOOS SSTs and climatology SSTs were used. KOOS SST data yielded an analysis error standard deviation value similar to OSTIA and NOAA NCDC (OISST) data. The KOOS SST shows lower random and sampling errors with increasing number of observations using six satellite datasets. In further studies, the proposed quality control methods for the KOOS SST system will be applied through more long-term case studies and comparisons with other SST systems.

  19. 21 CFR 111.55 - What are the requirements to implement a production and process control system?

    Science.gov (United States)

    2010-04-01

    ... production and process control system? 111.55 Section 111.55 Food and Drugs FOOD AND DRUG ADMINISTRATION... to Establish a Production and Process Control System § 111.55 What are the requirements to implement a production and process control system? You must implement a system of production and...

  20. Controls on the ratio of mesozooplankton production to primary production in marine ecosystems

    Science.gov (United States)

    Stock, Charles; Dunne, John

    2010-01-01

    An ecosystem model was used to (1) determine the extent to which global trends in the ratio of mesozooplankton production to primary production (referred to herein as the " z-ratio") can be explained by nutrient enrichment, temperature, and euphotic zone depth, and (2) quantitatively diagnose the mechanisms driving these trends. Equilibrium model solutions were calibrated to observed and empirically derived patterns in phytoplankton biomass and growth rates, mesozooplankton biomass and growth rates, and the fraction of phytoplankton that are large (>5 μm ESD). This constrained several otherwise highly uncertain model parameters. Most notably, half-saturation constants for zooplankton feeding were constrained by the biomass and growth rates of their prey populations, and low zooplankton basal metabolic rates were required to match observations from oligotrophic ecosystems. Calibrated model solutions had no major biases and produced median z-ratios and ranges consistent with estimates. However, much of the variability around the median values in the calibration dataset (72 points) could not be explained. Model results were then compared with an extended global compilation of z-ratio estimates (>10 000 points). This revealed a modest yet significant ( r=0.40) increasing trend in z-ratios from values ˜0.01-0.04 to ˜0.1-0.2 with increasing primary productivity, with the transition from low to high z-ratios occurring at lower primary productivity in cold-water ecosystems. Two mechanisms, both linked to increasing phytoplankton biomass, were responsible: (1) zooplankton gross growth efficiencies increased as their ingestion rates became much greater than basal metabolic rates and (2) the trophic distance between primary producers and mesozooplankton shortened as primary production shifted toward large phytoplankton. Mechanism (1) was most important during the transition from low to moderate productivity ecosystems and mechanism (2) was responsible for a relatively

  1. Complex shape product tolerance and accuracy control method for virtual assembly

    Science.gov (United States)

    Ma, Huiping; Jin, Yuanqiang; Zhang, Xiaoguang; Zhou, Hai

    2015-02-01

    The simulation of virtual assembly process for engineering design lacks of accuracy in the software of three-dimension CAD at present. Product modeling technology with tolerance, assembly precision preanalysis technique and precision control method are developed. To solve the problem of lack of precision information transmission in CAD, tolerance mathematical model of Small Displacement Torsor (SDT) is presented, which can bring about technology transfer and establishment of digital control function for geometric elements from the definition, description, specification to the actual inspection and evaluation process. Current tolerance optimization design methods for complex shape product are proposed for optimization of machining technology, effective cost control and assembly quality of the products.

  2. How NASA KSC Controls Interfaces with the use of Motion Skeletons and Product Structure

    Science.gov (United States)

    Jones, Corey

    2013-01-01

    This presentation will show how NASA KSC controls interfaces for Modular Product Architecture (MPA) using Locator Skeletons, Interface Skeletons, and Product Structure, to be combined together within a Motion Skeleton. The user will learn how to utilize skeleton models to communicate interface data, as successfully done at NASA KSC in their use of Motion Skeletons to control interfaces for multi-launch systems. There will be discussion of the methodology used to control design requirements through WTParts, and how to utilize product structure for non-CAD documents.

  3. Pathogen filtration to control plant disease outbreak in greenhouse production

    Science.gov (United States)

    Jeon, Sangho; Krasnow, Charles; Bhalsod, Gemini; Granke, Leah; Harlan, Blair; Hausbeck, Mary; Zhang, Wei

    2016-04-01

    Previous research has been extensively focused on understanding the fate and transport of human microbial pathogens in soil and water environments. However, little is known about the transport of plant pathogens, although these pathogens are often found in irrigation waters and could cause severe crop damage and economical loss. Water mold pathogens including Phytophthora spp. and Pythium spp. are infective to a wide range of vegetable and floriculture crops, and they are primarily harbored in soils and disseminated through water flow. It is challenging to control these pathogens because they often quickly develop resistance to many fungicides. Therefore, this multi-scale study aimed to investigate physical removal of plant pathogens from water by filtration, thus reducing the pathogen exposure risks to crops. In column-scale experiments, we studied controlling factors on the transport and retention of Phytophthora capsici zoospores in saturated columns packed with iron oxide coated-sand and uncoated-sand under varying solution chemistry. Biflagellate zoospores were less retained than encysted zoospores, and lower solution pH and greater iron oxide content increased the retention of encysted zoospores. These results provided insights on environmental dispersal of Phytophthora zoospores in natural soils as well as on developing cost-effective engineered filtration systems for pathogen removal. Using small-scale greenhouse filtration systems, we further investigated the performance of varying filter media (i.e., granular sand, iron oxide coated ceramic porous media, and activated carbon) in mitigating disease outbreaks of Phytophthora and Pythium for greenhouse-grown squash and poinsettia, respectively, in comparison with fungicide treatment. For squash, filtration by iron oxide coated media was more effective in reducing the Phytophthora infection, comparing to sand filtration and fungicide application. For poinsettia, sand filtration performed better in controlling

  4. DESIGN OF A CONTROL SYSTEM TO ENHANCE PROCESS PERFOMANCE IN THE PRODUCTION OF SORGHUM BEER

    OpenAIRE

    CATHERINE MAWARE; NORMAN GWANGWAVA; RAPHEL M JINGURA

    2013-01-01

    Breweries in Zimbabwe use limited or no control systems at all. The aim of this study was to design a control system for monitoring and controlling mashing and cooling processes during production of a sorghum beer brewing. The design of the control circuit was done using sensors and controllers. For temperature control a PID controller was used. The system was able to raise the temperature of the mash to 50°C for 50 minutes for hydrolysis of protein, β glucons and pentasons by proteolic enzym...

  5. Biodiesel production from waste frying oils and its quality control.

    Science.gov (United States)

    Sabudak, T; Yildiz, M

    2010-05-01

    The use of biodiesel as fuel from alternative sources has increased considerably over recent years, affording numerous environmental benefits. Biodiesel an alternative fuel for diesel engines is produced from renewable sources such as vegetable oils or animal fats. However, the high costs implicated in marketing biodiesel constitute a major obstacle. To this regard therefore, the use of waste frying oils (WFO) should produce a marked reduction in the cost of biodiesel due to the ready availability of WFO at a relatively low price. In the present study waste frying oils collected from several McDonald's restaurants in Istanbul, were used to produce biodiesel. Biodiesel from WFO was prepared by means of three different transesterification processes: a one-step base-catalyzed, a two-step base-catalyzed and a two-step acid-catalyzed transesterification followed by base transesterification. No detailed previous studies providing information for a two-step acid-catalyzed transesterification followed by a base (CH(3)ONa) transesterification are present in literature. Each reaction was allowed to take place with and without tetrahydrofuran added as a co-solvent. Following production, three different procedures; washing with distilled water, dry wash with magnesol and using ion-exchange resin were applied to purify biodiesel and the best outcome determined. The biodiesel obtained to verify compliance with the European Standard 14214 (EN 14214), which also corresponds to Turkish Biodiesel Standards.

  6. Dynamic optimization approach for integrated supplier selection and tracking control of single product inventory system with product discount

    Science.gov (United States)

    Sutrisno; Widowati; Heru Tjahjana, R.

    2017-01-01

    In this paper, we propose a mathematical model in the form of dynamic/multi-stage optimization to solve an integrated supplier selection problem and tracking control problem of single product inventory system with product discount. The product discount will be stated as a piece-wise linear function. We use dynamic programming to solve this proposed optimization to determine the optimal supplier and the optimal product volume that will be purchased from the optimal supplier for each time period so that the inventory level tracks a reference trajectory given by decision maker with minimal total cost. We give a numerical experiment to evaluate the proposed model. From the result, the optimal supplier was determined for each time period and the inventory level follows the given reference well.

  7. Controlling the production and distribution of drugs in communist Poland.

    Science.gov (United States)

    Łotysz, Sławomir

    2014-01-01

    Between 1944 and 1989--the period of communist power in Poland--the national pharmaceutical market experienced several dramatic changes. The country was a prodigious importer of drugs following the Second World War, with a large portion of the medicine received being donated by various aid organisations. In the 1960s, Poland became a significant exporter of drugs to the Eastern Bloc countries, but dropped down the list of meaningful producers again after the post-1989 transformation. For four and a half decades the pharmaceutical market in Poland had been a scene of political and ideological struggle. The companies, owned and controlled by the state, were poorly managed, being neither innovative nor competitive. This fact, along with the state's irrational and inconsequent drug policy, caused an almost permanent shortage in drug supplies for patients: ironic for a socialist system in which universal and free health care was a basic principle.

  8. Sequential oxygenation of linoleic acid in the fungus Gaeumannomyces graminis: stereochemistry of dioxygenase and hydroperoxide isomerase reactions.

    Science.gov (United States)

    Hamberg, M; Zhang, L Y; Brodowsky, I D; Oliw, E H

    1994-02-15

    Linoleic acid is sequentially oxygenated to (7S,8S)-dihydroxylinoleic acid by dioxygenase and hydroperoxide isomerase activities present in the fungus Gaeumannomyces graminis (Brodowsky, I. D., Hamberg, M., and Oliw, E. H., J. Biol. Chem. 267, 14738-14745 (1992)). Linoleic acids stereospecifically deuterated at C-7 and C-8 were prepared by biological desaturation of the corresponding stearates and used to determine the stereochemistry of the hydrogen abstractions occurring in the dioxygenase- and hydroperoxide isomerase-catalyzed reactions. The dioxygenase reaction was found to involve stereospecific abstraction of the pro-S hydrogen from C-8 followed by antarafacial insertion of dioxygen to produce (8R)-hydroperoxylinoleic acid. The hydroperoxide isomerase reaction consisted of conversion of (8R)-hydroperoxylinoleic acid into (7S,8S)-dihydroxylinoleic acid by stereospecific elimination of the pro-S hydrogen from C-7 and intramolecular suprafacial insertion of oxygen at C-7. Accordingly, during the conversion of linoleic acid into (8R)-hydroperoxylinoleic acid, the absolute configuration of C-8 was inverted, while the conversion of (8R)-hydroperoxylinoleic acid into (7S,8S)-dihydroxylinoleic acid occurred with retention of absolute configuration at C-7.

  9. Cell-penetrating compounds preferentially bind glycosaminoglycans over plasma membrane lipids in a charge density- and stereochemistry-dependent manner.

    Science.gov (United States)

    Prevette, Lisa E; Benish, Nicolas C; Schoenecker, Amber R; Braden, Kristin J

    2015-12-01

    Cell-penetrating compounds (CPCs) are often conjugated to drugs and genes to facilitate cellular uptake. We hypothesize that the electrostatic interaction between the positively charged amines of the cell-penetrating compounds and the negatively charged glycosaminoglycans (GAGs) extending from cell surfaces is the initiating step in the internalization process. The interactions of generation 5 PAMAM dendrimer, Tat peptide and 25 kDa linear PEI with four different GAGs have been studied using isothermal titration calorimetry to elucidate structure-function relationships that could lead to improved drug and gene delivery methods to a wide variety of cell types. Detailed thermodynamic analysis has determined that CPC-GAG binding constants range from 8.7×10(3) to 2.4×10(6)M(-1) and that affinity is dependent upon GAG charge density and stereochemistry and CPC molecular weight. The effect of GAG composition on affinity is likely due to hydrogen bonding between CPC amines and amides and GAG hydroxyl and amine groups. These results were compared to the association of CPCs with lipid vesicles of varying composition as model plasma membranes to finally clarify the relative importance of each cell surface component in initial cell recognition. CPC-lipid affinity increases with anionic lipid content, but GAG affinity is higher for all cell-penetrating compounds, confirming the role these heterogeneous polysaccharides play in cellular association and clustering.

  10. Collapsed bipolar glycolipids at the air/water interface: effect of the stereochemistry on the stretched/bent conformations.

    Science.gov (United States)

    Jacquemet, Alicia; Terme, Nolwenn; Benvegnu, Thierry; Vié, Véronique; Lemiègre, Loïc

    2013-12-15

    This article describes a comparative study of several bipolar lipids derived from tetraether structures. The sole structural difference between the main two glycolipids is a unique stereochemical variation on a cyclopentyl ring placed in the middle of the lipids. We discuss the comparative results obtained at the air/water interface on the basis of tensiometry and ellipsometry. Langmuir-Blodgett depositions during lipid film compressions and decompressions were also analyzed by AFM. The lactosylated tetraether (bipolar) lipid structures involved the formation of highly stable multilayers, which are still present at 10 mN m(-1) during decompression. This study suggests also that the stereochemistry of a central cyclopentyl ring dramatically drives the conformation of the corresponding bipolar lipids. Both isomers (trans and cis) adopt a U-shaped (bent) conformation at the air/water interface but the trans cyclopentyl ring induces a much more frustration within this type of conformation. Consequently, this bipolar lipid (trans-tetraether) undergoes a flip of one polar head-group (lactosyl) leading to a stretched conformation during collapse.

  11. Effect of Stereochemistry on Directed Self-Assembly of Poly(styrene-b-lactide) Films on Chemical Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiao; Liu, Yadong; Wan, Lei; Li, Zhaolei; Suh, Hyoseon; Ren, Jiaxing; Ocola, Leonidas E.; Hu, Wenbing; Ji, Shengxiang; Nealey, Paul F.

    2016-03-15

    We demonstrated here for the first time that the stereochemistry of polylactide (PLA) blocks affected the assembly behaviors of PS-b-PLA on chemical patterns. Two PS-b-PLA block copolymers, where the PLA block is either racemic (PDLLA) or left-handed (PLLA), were synthesized and directed to assemble on chemical patterns with a wide range of L-s/L-o. PS-b-PDLLA was stretched up to 70% on chemical patterns, while PS-b-PLLA was only stretched by 20%. The assembly behavior of PS-b-PDLLA was different from AB diblock copolymer, but similar to that of ABA triblock copolymer. The high stretchability might be attributed to the formation of stereocomplexes in PDLLA blocks. Compared to ABA triblock copolymers, stereocomplexed diblock copolymers have much faster assembly kinetics. This observation provides a new concept to achieve large process windows by the introduction of specific interactions, for example, H-bonding, supramolecular interaction, and sterecomplexation, between polymer chains.

  12. Optimal control strategies for hydrogen production when coupling solid oxide electrolysers with intermittent renewable energies

    Science.gov (United States)

    Cai, Qiong; Adjiman, Claire S.; Brandon, Nigel P.

    2014-12-01

    The penetration of intermittent renewable energies requires the development of energy storage technologies. High temperature electrolysis using solid oxide electrolyser cells (SOECs) as a potential energy storage technology, provides the prospect of a cost-effective and energy efficient route to clean hydrogen production. The development of optimal control strategies when SOEC systems are coupled with intermittent renewable energies is discussed. Hydrogen production is examined in relation to energy consumption. Control strategies considered include maximizing hydrogen production, minimizing SOEC energy consumption and minimizing compressor energy consumption. Optimal control trajectories of the operating variables over a given period of time show feasible control for the chosen situations. Temperature control of the SOEC stack is ensured via constraints on the overall temperature difference across the cell and the local temperature gradient within the SOEC stack, to link materials properties with system performance; these constraints are successfully managed. The relative merits of the optimal control strategies are analyzed.

  13. Control and Diagnosis in Integrated Product Development - Observations during the Development of an AGV

    Science.gov (United States)

    Stetter, R.; Simundsson, A.

    2015-11-01

    This paper is concerned with the integration of control and diagnosis functionalities into the development of complete systems which include mechanical, electrical and electronic subsystems. For the development of such systems the strategies, methods and tools of integrated product development have attracted significant attention during the last decades. Today, it is generally observed that product development processes of complex systems can only be successful if the activities in the different domains are well connected and synchronised and if an ongoing communication is present - an ongoing communication spanning the technical domains and also including functions such as production planning, marketing/distribution, quality assurance, service and project planning. Obviously, numerous approaches to tackle this challenge are present in scientific literature and in industrial practice, as well. Today, the functionality and safety of most products is to a large degree dependent on control and diagnosis functionalities. Still, there is comparatively little research concentrating on the integration of the development of these functionalities into the overall product development processes. The main source of insight of the presented research is the product development process of an Automated Guided Vehicle (AGV) which is intended to be used on rough terrain. The paper starts with a background describing Integrated Product Development. The second section deals with the product development of the sample product. The third part summarizes some insights and formulates first hypotheses concerning control and diagnosis in Integrated Product Development.

  14. Control of neutrophil inflammation at mucosal surfacesby secreted epithelial products

    Directory of Open Access Journals (Sweden)

    Rose L. Szabady

    2013-07-01

    Full Text Available The human intestine is a large and delicately balanced organ, responsible for efficiently absorbing nutrients and selectively eliminating disease-causing pathogens. The gut architecture consists of a single layer of epithelial cells that forms a barrier against the food antigens and resident microbiota within the lumen. This barrier is augmented by a thick layer of mucus on the luminal side and an underlying lamina propria containing a resident population of immune cells. Attempted breaches of the intestinal barrier by pathogenic bacteria result in the rapid induction of a coordinated innate immune response that includes release of antimicrobial peptides, activation of pattern recognition receptors, and recruitment of various immune cells. In recent years, the role of epithelial cells in initiating this immune response has been increasingly appreciated. In particular, epithelial cells are responsible for the release of a variety of factors that attract neutrophils, the body’s trained bacterial killers. In this review we will highlight recent research that details a new understanding of how epithelial cells directionally secrete specific compounds at distinct stages of the inflammatory response in order to coordinate the immune response to intestinal microbes. In addition to their importance during the response to infection, evidence suggests that dysregulation of these pathways may contribute to pathologic inflammation during inflammatory bowel disease. Therefore, a continued understanding of the mechanisms by which epithelial cells control neutrophil migration into the intestine will have tremendous benefits in both the understanding of biological processes and the identification of potential therapeutic targets.

  15. In-process control data acquisition and analysis in tablet production

    OpenAIRE

    Hribar , Erik

    2012-01-01

    The diploma thesis will study the problem of process data acquisition and analysis. It describes the upgrade of current information system for in-process control in tablet production. We will establish the system for overview and archiving of measurements from tableting machine control unit. We will prepare various statistical views for comparison of data from current system and archived measurements from tableting machine control unit. Current information system for in-process control maint...

  16. Lactone-bound structures of cyclohexanone monooxygenase provide insight into the stereochemistry of catalysis.

    Science.gov (United States)

    Yachnin, Brahm J; McEvoy, Michelle B; MacCuish, Roderick J D; Morley, Krista L; Lau, Peter C K; Berghuis, Albert M

    2014-12-19

    The Baeyer-Villiger monooxygenases (BVMOs) are microbial enzymes that catalyze the synthetically useful Baeyer-Villiger oxidation reaction. The available BVMO crystal structures all lack a substrate or product bound in a position that would determine the substrate specificity and stereospecificity of the enzyme. Here, we report two crystal structures of cyclohexanone monooxygenase (CHMO) with its product, ε-caprolactone, bound: the CHMO(Tight) and CHMO(Loose) structures. The CHMO(Tight) structure represents the enzyme state in which substrate acceptance and stereospecificity is determined, providing a foundation for engineering BVMOs with altered substrate spectra and/or stereospecificity. The CHMO(Loose) structure is the first structure where the product is solvent accessible. This structure represents the enzyme state upon binding and release of the substrate and product. In addition, the role of the invariant Arg329 in chaperoning the substrate/product during the catalytic cycle is highlighted. Overall, these data provide a structural framework for the engineering of BVMOs with altered substrate spectra and/or stereospecificity.

  17. 78 FR 49766 - Certain Products Containing Interactive Program Guide and Parental Control Technology; Commission...

    Science.gov (United States)

    2013-08-15

    ... From the Federal Register Online via the Government Publishing Office INTERNATIONAL TRADE COMMISSION Certain Products Containing Interactive Program Guide and Parental Control Technology; Commission... public inspection at the Office of the Secretary and on EDIS. The authority for the Commission's...

  18. Design of Control System for Flexible Packaging Bags Palletizing Production Line Based on PLC

    Science.gov (United States)

    Zheng, Huiping; Chen, Lin; Zhao, Xiaoming; Liu, Zhanyang

    Flexible packaging bags palletizing production line is to put the bags in the required area according to particular order and size, in order to finish handling, storage, loading and unloading, transportation and other logistics work of goods. Flexible packaging bags palletizing line is composed of turning bags mechanism, shaping mechanism, indexing mechanism, marshalling mechanism, pushing bags mechanism, pressing bags mechanism, laminating mechanism, elevator, tray warehouse, tray conveyor and loaded tray conveyor. Whether the whole production line can smoothly run depends on each of the above equipment and precision control among them. In this paper the technological process and the control logic of flexible packaging bags palletizing production line is introduced. Palletizing process of the production line realized automation by means of a control system based on programmable logic controller (PLC). It has the advantages of simple structure, reliable and easy maintenance etc.

  19. Optimal control of a batch bioreactor for the production of a novel ...

    African Journals Online (AJOL)

    Optimal control of a batch bioreactor for the production of a novel antifungal substance CF66I. ... Log in or Register to get access to full text downloads. ... lower temperature shortens the fermentation time, reduce heating energy and the cost.

  20. Control of exoenzyme production, motility and cell differentiation in Serratia liquefaciens

    DEFF Research Database (Denmark)

    Givskov, Michael Christian; Eberl, Leo; Molin, Søren

    1997-01-01

    Serratia liquefaciens secretes a broad spectrum of hydrolytic enzymes to the surrounding medium and possesses the ability to differentiate into specialized swarmer cells capable of rapid surface motility. Control of exoenzyme production and swarming motility is governed by similar regulatory...

  1. Impact of sustaining a controlled residual growth on polyhydroxybutyrate yield and production kinetics in Cupriavidus necator.

    Science.gov (United States)

    Grousseau, Estelle; Blanchet, Elise; Déléris, Stéphane; Albuquerque, Maria G E; Paul, Etienne; Uribelarrea, Jean-Louis

    2013-11-01

    In this study a complementary modeling and experimental approach was used to explore how growth controls the NADPH generation and availability, and the resulting impact on PHB (polyhydroxybutyrate) yields and kinetics. The results show that the anabolic demand allowed the NADPH production through the Entner-Doudoroff (ED) pathway, leading to a high maximal theoretical PHB production yield of 0.89 C mole C mole(-1); whereas without biomass production, NADPH regeneration is only possible via the isocitrate dehydrogenase leading to a theoretical yield of 0.67 C mole C mole(-1). Furthermore, the maximum specific rate of NADPH produced at maximal growth rate (to fulfil biomass requirement) was found to be the maximum set in every conditions, which by consequence determines the maximal PHB production rate. These results imply that sustaining a controlled residual growth improves the PHB specific production rate without altering production yield. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Design requirements for SRB production control system. Volume 3: Package evaluation, modification and hardware

    Science.gov (United States)

    1981-01-01

    The software package evaluation was designed to analyze commercially available, field-proven, production control or manufacturing resource planning management technology and software package. The analysis was conducted by comparing SRB production control software requirements and conceptual system design to software package capabilities. The methodology of evaluation and the findings at each stage of evaluation are described. Topics covered include: vendor listing; request for information (RFI) document; RFI response rate and quality; RFI evaluation process; and capabilities versus requirements.

  3. The regional control of the canadian energy production; Le contraste provincial de la production energetique canadienne

    Energy Technology Data Exchange (ETDEWEB)

    Petitlaurent, S.; Sarrazin, J

    2004-12-01

    This document provides information and presents data on the energy situation in many regions of Canada. The first part deals with the petroleum and the bitumen shales of Alberta (reserves, exploitation and production, environmental impacts), the second part discusses with the hydroelectricity choice of Quebec and the 2004 crisis. The nuclear situation of Ontario is presented in the third part (nuclear park, programs, uranium reserves, research and development on Candu reactors), while the fourth part deals with the renewable energies (wind power and biomass). The canadian situation facing the Kyoto protocol is discussed in the last part. (A.L.B.)

  4. Image Analysis of Pellet Size for a Control System in Industrial Feed Production

    DEFF Research Database (Denmark)

    Ljungqvist, Martin Georg; Nielsen, Michael Engelbrecht; Ersbøll, Bjarne Kjær

    2011-01-01

    When producing aquaculture fish feed pellets, the size of the output product is of immense importance. As the production method cannot produce pellets of constant and uniform size using constant machine settings, there is a demand for size control. Fish fed with feed pellets of improper size...

  5. Effects of Controlled Release Fertilizer on the Post-Production Performance of Impatiens Wallerana

    Science.gov (United States)

    Controlled release fertilizers (CRF) in production systems have been known to reduce environmental contamination. However, there is a lot to be explored as per its use in bedding plant production. Bedding plant growers have not adapted CRF use because there is little information about its use and ...

  6. 76 FR 23823 - Guidance for Industry on Fish and Fishery Products Hazards and Controls, Fourth Edition...

    Science.gov (United States)

    2011-04-28

    ... principles of HACCP. Fish and fishery products are adulterated under section 402(a)(4) of the Federal Food... chapter has been added containing guidance for the control of pathogen survival through processes designed... HUMAN SERVICES Food and Drug Administration Guidance for Industry on Fish and Fishery Products...

  7. Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

    NARCIS (Netherlands)

    Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

    2013-01-01

    Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

  8. Optimisation of product quality and minimisation of its variation in climate controlled operations

    NARCIS (Netherlands)

    Verdijck, G.J.C.; Straten, van G.; Preisig, H.A.

    2005-01-01

    An optimisation procedure is presented for direct control of product quality of agro-material and minimisation of its quality variation. The procedure builds on a previously presented model structure, which is briefly reviewed, together forming a methodological framework for direct product quality c

  9. Optimisation of product quality and minimisation of its variation in climate controlled operations

    NARCIS (Netherlands)

    Verdijck, G.J.C.; Straten, van G.; Preisig, H.A.

    2005-01-01

    An optimisation procedure is presented for direct control of product quality of agro-material and minimisation of its quality variation. The procedure builds on a previously presented model structure, which is briefly reviewed, together forming a methodological framework for direct product quality

  10. Demonstrating multi-layered MAS in control of offshore oil and gas production

    DEFF Research Database (Denmark)

    Lindegaard Mikkelsen, Lars; Næumann, J. R.; Demazeau, Y.

    2013-01-01

    From a control perspective, offshore oil and gas production is very challenging due to the many and potentially conflicting production objectives that arise from the intrinsic complexity of the oil and gas domain. In this paper, we demonstrate how a multi-layered multi-agent system can be used...

  11. Non-ideal feedforward torque control of wind turbines: Impacts on annual energy production & gross earnings

    Science.gov (United States)

    Hackl, Christoph; Schechner, Korbinian

    2016-09-01

    We discuss non-ideal torque control in wind turbine systems. Most high-level controllers generate a reference torque which is then send to the underlying electrical drive system (generator+inverter) of the wind turbine system to steer the turbine/generator to its optimal operation point (depending on the wind speed). The energy production heavily depends on the mechanical power (i.e. the product of rotational speed and generator torque). However, since torque sensors in the MW range are not available or extremely expensive, the underlying torque control system is implemented as feedforward control and, therefore, is inherently sensitive to parameter variations/uncertainties. Based on real wind data and a wind turbine system model, we discuss causes and impacts of non-ideal feedforward torque control on the energy production and the annual gross earnings.

  12. Exploring the Stereochemistry of the Wittig Reaction: The Unexpected Influence of a Nominal Spectator Ion

    Science.gov (United States)

    Hanson, John; Dasher, Bill; Scharrer, Eric; Hoyt, Tim

    2010-01-01

    Students in the second-semester organic chemistry laboratory perform a Wittig reaction between butylidenetriphenylphosphorane (an ylide) and benzaldehyde and determine the relative percentages of the cis and trans isomers of the 1-phenyl-1-pentene product. Because of the highly reactive nature of this unstabilized ylide, students are introduced to…

  13. EWMA Controller with Concurrent Adjustment for a High-Mixed Production Process

    Directory of Open Access Journals (Sweden)

    Shui-Pin Lee

    2017-01-01

    Full Text Available The exponentially weighted moving average (EWMA feedback controller is a very popular run-to-run (RtR process control scheme in the semiconductor industry. Traditionally, the manufacturing environment was simplified as a single product and single tool process. In the feedback control, the adjustment of the recipe for the next run is related to the deviation of the current output against the desired target. However, in a commercial foundry, every tool always works for many products. It is called a multiple products and single tool (MPST process. The challenge of this process is how to adjust the recipes among different products in a production row.In this study, a modified threaded EWMA feedback controller, the EWMA with concurrent adjustment, is proposed to deal with the issue of multiple products in a tool. When the process disturbances follow an IMA(1,1 time series model, the stability of the proposed method will be proven. The optimum discount factors of the proposed EWMA controller will be investigated by several simulations in terms of the number of multiple products, their distribution and the scheduling of the process. Moreover, according to results of the performance comparisons with threaded EWMA, the proposed controller is advantage in the large number of multiple products and in low-frequency products .

  14. Strategy for product composition control in the Hanford Waste Vitrification Plant

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, M.F.; Piepel, G.F.

    1996-03-01

    The Hanford Waste Vitrification Plant (HWVP) will immobilize transuranic and high-level radioactive waste in borosilicate glass. The major objective of the Process/Product Model Development (PPMD) cost account of the Pacific Northwest Laboratory HWVP Technology Development (PHTD) Project is the development of a system for guiding control of feed slurry composition (which affects glass properties) and for checking and documenting product quality. This document lays out the broad structure of HWVP`s product composition control system, discusses five major algorithms and technical issues relevant to this system, and sketches the path of development and testing.

  15. Potential for widespread application of biological control of stored-product pests

    DEFF Research Database (Denmark)

    Hansen, Lise Stengaard

    2007-01-01

    Biological control of stored product pests has substantial potential in Europe". This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biological......, beetles and moths; (2) Preventative treatment of bulk commodities against weevils (Sitophilus spp.) and storage mites; (3) Preventative application of egg-parasitoids against moths in packaged products. Development of methods for biological control and of mass production of natural enemies...

  16. Analysis and control of Boolean networks a semi-tensor product approach

    CERN Document Server

    Cheng, Daizhan; Li, Zhiqiang

    2010-01-01

    This book presents a new approach to the investigation of Boolean control networks, using the semi-tensor product (STP), which can express a logical function as a conventional discrete-time linear system. This makes it possible to analyze basic control problems.

  17. Effectiveness of sulfuryl fluoride for control of different life stages of stored-product psocids (Psocoptera)

    Science.gov (United States)

    With the impending phase-out of methyl bromide, sulfuryl fluoride is among the most promising alternative fumigant insecticides. It has been evaluated for control of several insect species, but there are few data available on its efficacy for control of stored-product psocids (Psocoptera). We evalua...

  18. Analysis of power and frequency control requirements in view of increased decentralized production and market liberalization

    NARCIS (Netherlands)

    Roffel, B; de Boer, WW

    2003-01-01

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed. Fi

  19. 76 FR 46841 - Certain Products Containing Interactive Program Guides and Parental Controls Technology; Notice...

    Science.gov (United States)

    2011-08-03

    ... COMMISSION Certain Products Containing Interactive Program Guides and Parental Controls Technology; Notice of... program guide and parental controls technology by reason of the infringement of certain claims of U.S... Commission has determined not to review the ID. The authority for the Commission's determination is contained...

  20. Analysis of power and frequency control requirements in view of increased decentralized production and market liberization

    NARCIS (Netherlands)

    Roffel, B.; de Boer, Wouter W.

    2003-01-01

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed.

  1. Analysis of power and frequency control requirements in view of increased decentralized production and market liberalization

    NARCIS (Netherlands)

    Roffel, B; de Boer, WW

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed.

  2. Analysis of power and frequency control requirements in view of increased decentralized production and market liberalization

    NARCIS (Netherlands)

    Roffel, B; de Boer, WW

    2003-01-01

    This paper presents a systematic approach of the analysis of the minimum control requirements that are imposed on power producing units in the Netherlands, especially in the case when decentralized production increases. Also some effects of the liberalization on the control behavior are analyzed. Fi

  3. Effect of gaseous ozone for control of stored product pests at low and high temperature

    DEFF Research Database (Denmark)

    Hansen, Lise Stengård; Hansen, Peer; Vagn Jensen, Karl-Martin

    2013-01-01

    Gaseous ozone (O3) has shown potential for control of insects in stored grain. A previous laboratory study determined doses of ozone necessary to control freely exposed and internal stages of eleven stored product pest species at 20 C. In this study the impact of temperature on the effect of ozon...

  4. Designing RNA-based genetic control systems for efficient production from engineered metabolic pathways.

    Science.gov (United States)

    Stevens, Jason T; Carothers, James M

    2015-02-20

    Engineered metabolic pathways can be augmented with dynamic regulatory controllers to increase production titers by minimizing toxicity and helping cells maintain homeostasis. We investigated the potential for dynamic RNA-based genetic control systems to increase production through simulation analysis of an engineered p-aminostyrene (p-AS) pathway in E. coli. To map the entire design space, we formulated 729 unique mechanistic models corresponding to all of the possible control topologies and mechanistic implementations in the system under study. Two thousand sampled simulations were performed for each of the 729 system designs to relate the potential effects of dynamic control to increases in p-AS production (total of 3 × 10(6) simulations). Our analysis indicates that dynamic control strategies employing aptazyme-regulated expression devices (aREDs) can yield >10-fold improvements over static control. We uncovered generalizable trends in successful control architectures and found that highly performing RNA-based control systems are experimentally tractable. Analyzing the metabolic control state space to predict optimal genetic control strategies promises to enhance the design of metabolic pathways.

  5. Advanced process monitoring and feedback control to enhance cell culture process production and robustness.

    Science.gov (United States)

    Zhang, An; Tsang, Valerie Liu; Moore, Brandon; Shen, Vivian; Huang, Yao-Ming; Kshirsagar, Rashmi; Ryll, Thomas

    2015-12-01

    It is a common practice in biotherapeutic manufacturing to define a fixed-volume feed strategy for nutrient feeds, based on historical cell demand. However, once the feed volumes are defined, they are inflexible to batch-to-batch variations in cell growth and physiology and can lead to inconsistent productivity and product quality. In an effort to control critical quality attributes and to apply process analytical technology (PAT), a fully automated cell culture feedback control system has been explored in three different applications. The first study illustrates that frequent monitoring and automatically controlling the complex feed based on a surrogate (glutamate) level improved protein production. More importantly, the resulting feed strategy was translated into a manufacturing-friendly manual feed strategy without impact on product quality. The second study demonstrates the improved process robustness of an automated feed strategy based on online bio-capacitance measurements for cell growth. In the third study, glucose and lactate concentrations were measured online and were used to automatically control the glucose feed, which in turn changed lactate metabolism. These studies suggest that the auto-feedback control system has the potential to significantly increase productivity and improve robustness in manufacturing, with the goal of ensuring process performance and product quality consistency.

  6. Prolactin as a Candidate Gene Controlling Molting and Egg Production of Duck

    Directory of Open Access Journals (Sweden)

    Triana Susanti

    2015-03-01

    Full Text Available Incidence of molting is a crucial problem in the local ducks that need to be handled from many aspects including genetic aspect. Handling of molting genetically can be done quickly and accurately when the control genes have been found. The search for marker genes of molting can be conducted in poultry through broodiness naturally, because its physiological processes are related to the continuity of egg production. This paper describes the mechanism of molting, the relationship of molting with prolactin hormone and the association of prolactin gene polymorphism with molting and egg production. Molting and egg production were influenced by the prolactin hormone, that may be controlled by the prolactin gene. High concentration of prolactin hormone will inhibit the function of pituitary gland, decreasing production of gonadotrophin hormone (follicle stimulating hormone and luteinizing hormone hence ovulation ceased. This will stop egg production and at the same time molting proccess occurred.

  7. Biosynthesis of monoterpenes. Stereochemistry of the enzymatic cyclizations of geranyl pyrophosphate to (+)-alpha-pinene and (-)-beta-pinene

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, R.; Satterwhite, D.M.; Wheeler, C.J.; Felton, N.M.

    1989-02-05

    The conversion of geranyl pyrophosphate to (+)-alpha-pinene and to (-)-beta-pinene is considered to proceed by the initial isomerization of the substrate to (-)-(3R)- and to (+)-(3S)-linalyl pyrophosphate, respectively, and the subsequent cyclization of the anti, endo-conformer of these bound intermediates by mirror-image sequences which should result in the net retention of configuration at C1 of the geranyl precursor. Incubation of (1R)-(2-14C,1-3H)- and (1S)-(2-14C,1-3H)geranyl pyrophosphate with (+)-pinene cyclase and with (-)-pinene cyclase from common sage (Salvia officinalis) gave labeled (+)-alpha- and (-)-beta-pinene of unchanged 3H/14C ratio in all cases, and the (+)- and (-)-olefins were stereoselectively converted to (+)- and (-)-borneol, respectively, which were oxidized to the corresponding (+)- and (-)-isomers of camphor, again without change in isotope ratio. The location of the tritium was determined in each case by stereoselective, base-catalyzed exchange of the exo-alpha-hydrogens of these derived ketones. The results indicated that the configuration at C1 of the substrate was retained in the enzymatic transformations to the (+)- and (-)-pinenes, which is entirely consistent with the syn-isomerization of geranyl pyrophosphate to linalyl pyrophosphate, transoid to cisoid rotation, and anti, endo-cyclization of the latter. The absolute stereochemical elements of the antipodal reaction sequences were confirmed by the selective enzymatic conversions of (3R)- and (3S)-1Z-(1-3H)linalyl pyrophosphate to (+)-alpha-pinene and (-)-beta-pinene, respectively, and by the location of the tritium in the derived camphors as before. The summation of the results fully defines the overall stereochemistry of the coupled isomerization and cyclization of geranyl pyrophosphate to the antipodal pinenes.

  8. Effect of stereochemistry, chain length and sequence pattern on antimicrobial properties of short synthetic β-sheet forming peptide amphiphiles.

    Science.gov (United States)

    Ong, Zhan Yuin; Cheng, Junchi; Huang, Yuan; Xu, Kaijin; Ji, Zhongkang; Fan, Weimin; Yang, Yi Yan

    2014-01-01

    In the face of mounting global antibiotics resistance, the identification and development of membrane-active antimicrobial peptides (AMPs) as an alternative class of antimicrobial agent have gained significant attention. The physical perturbation and disruption of microbial membranes by the AMPs have been proposed to be an effective means to overcome conventional mechanisms of drug resistance. Recently, we have reported the design of a series of short synthetic β-sheet folding peptide amphiphiles comprised of recurring (X1Y1X2Y2)n-NH2 sequences where X: hydrophobic amino acids, Y: cationic amino acids and n: number of repeat units. In efforts to investigate the effects of key parameters including stereochemistry, chain length and sequence pattern on antimicrobial effects, systematic d-amino acid substitutions of the lead peptides (IRIK)2-NH2 (IK8-all L) and (IRVK)3-NH2 (IK12-all L) were performed. It was found that the corresponding D-enantiomers exhibited stronger antimicrobial activities with minimal or no change in hemolytic activities, hence translating very high selectivity indices of 407.0 and >9.8 for IK8-all D and IK12-all D respectively. IK8-all D was also demonstrated to be stable to degradation by broad spectrum proteases trypsin and proteinase K. The membrane disrupting bactericidal properties of IK8-all D effectively prevented drug resistance development and inhibited the growth of various clinically isolated MRSA, VRE, Acinetobacter baumanni, Pseudomonas aeruginosa, Cryptococcus. neoformans and Mycobacterium tuberculosis. Significant reduction in intracellular bacteria counts was also observed following treatment with IK8-all D in the Staphylococcus. aureus infected mouse macrophage cell line RAW264.7 (P < 0.01). These results suggest that the d-amino acids substituted β-sheet forming peptide IK8-all D with its enhanced antimicrobial activities and improved protease stability, is a promising therapeutic candidate with potential to combat

  9. Correlation between the Stereochemistry and Bioactivity in Octahedral Rhodium Prolinato Complexes

    NARCIS (Netherlands)

    Rajaratnam, Rajathees; Martin, Elisabeth K.; Doerr, Markus; Harms, Klaus; Casini, Angela; Meggers, Eric

    2015-01-01

    Controlling the relative and absolute configuration of octahedral metal complexes constitutes a key challenge that needs to be overcome in order to fully exploit the structural properties of octahedral metal complexes for applications in the fields of catalysis, materials sciences, and life

  10. Co-production of acetone and ethanol with molar ratio control enables production of improved gasoline or jet fuel blends.

    Science.gov (United States)

    Baer, Zachary C; Bormann, Sebastian; Sreekumar, Sanil; Grippo, Adam; Toste, F Dean; Blanch, Harvey W; Clark, Douglas S

    2016-10-01

    The fermentation of simple sugars to ethanol has been the most successful biofuel process to displace fossil fuel consumption worldwide thus far. However, the physical properties of ethanol and automotive components limit its application in most cases to 10-15 vol% blends with conventional gasoline. Fermentative co-production of ethanol and acetone coupled with a catalytic alkylation reaction could enable the production of gasoline blendstocks enriched in higher-chain oxygenates. Here we demonstrate a synthetic pathway for the production of acetone through the mevalonate precursor hydroxymethylglutaryl-CoA. Expression of this pathway in various strains of Escherichia coli resulted in the co-production of acetone and ethanol. Metabolic engineering and control of the environmental conditions for microbial growth resulted in controllable acetone and ethanol production with ethanol:acetone molar ratios ranging from 0.7:1 to 10.0:1. Specifically, use of gluconic acid as a substrate increased production of acetone and balanced the redox state of the system, predictively reducing the molar ethanol:acetone ratio. Increases in ethanol production and the molar ethanol:acetone ratio were achieved by co-expression of the aldehyde/alcohol dehydrogenase (AdhE) from E. coli MG1655 and by co-expression of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (AdhB) from Z. mobilis. Controlling the fermentation aeration rate and pH in a bioreactor raised the acetone titer to 5.1 g L(-1) , similar to that obtained with wild-type Clostridium acetobutylicum. Optimizing the metabolic pathway, the selection of host strain, and the physiological conditions employed for host growth together improved acetone titers over 35-fold (0.14-5.1 g/L). Finally, chemical catalysis was used to upgrade the co-produced ethanol and acetone at both low and high molar ratios to higher-chain oxygenates for gasoline and jet fuel applications. Biotechnol. Bioeng. 2016;113: 2079-2087. © 2016 Wiley

  11. Dynamic control of photosynthetic photon flux for lettuce production in CELSS

    Science.gov (United States)

    Chun, C.; Mitchell, C. A.

    1996-01-01

    A new dynamic control of photosynthetic photon flux (PPF) was tested using lettuce canopies growing in the Minitron II plant-growth/canopy gas-exchange system. Canopy photosynthetic rates (Pn) were measured in real time and fedback for further environment control. Pn can be manipulated by changing PPF, which is a good environmental parameter for dynamic control of crop production in a Controlled Ecological Life-Support Systems CELSS. Decision making that combines empirical mathematical models with rule sets developed from recent experimental data was tested. With comparable yield indices and potential for energy savings, dynamic control strategies will contribute greatly to the sustainability of space-deployed CELSS.

  12. Use of statistical process control in the production of blood components

    DEFF Research Database (Denmark)

    Magnussen, K; Quere, S; Winkel, P

    2008-01-01

    Introduction of statistical process control in the setting of a small blood centre was tested, both on the regular red blood cell production and specifically to test if a difference was seen in the quality of the platelets produced, when a change was made from a relatively large inexperienced...... by an experienced staff with four technologists. We applied statistical process control to examine if time series of quality control values were in statistical control. Leucocyte count in red blood cells was out of statistical control. Platelet concentration and volume of the platelets produced by the occasional...

  13. Unified Information Access in Product Creation with an Integrated Control Desk

    Science.gov (United States)

    Wrasse, Kevin; Diener, Holger; Hayka, Haygazun; Stark, Rainer

    2017-06-01

    Customers demand for individualized products leads to a large variety of different products in small series and single-unit production. A high flexibility pressure in product creation is one result of this trend. In order to counteract the pressure, the information steadily increasing by Industry 4.0 must be made available at the workplace. Additionally, a better exchange of information between product development, production planning and production is necessary. The improvement of individual systems, like CAD, PDM, ERP and MES, can only achieve this to a limited extent. Since they mostly use systems from different manufacturers, the necessary deeper integration of information is only feasible for SMEs to a limited extend. The presented control desk helps to ensure a more flexible product creation as well as information exchange. It captures information from different IT systems in the production process and presents them integrated, task-oriented and oriented to the user’s mental model, e.g. information of the production combined with the 3D model of product parts, or information about product development on the 3D model of the production. The solution is a digital 3D model of the manufacturing environment, which is enriched by billboards for a quick information overview and web service windows to access detailed MES and PDM information. By this, the level of abstraction can be reduced and reacts to changed requirements in the short term, making informed decisions. The interaction with the control stands utilizes the touch skills of mobile and fixed systems such as smartphones, tablets and multitouch tables.

  14. Tensor Product Model Transformation-based Controller Design for Gantry Crane Control System – An Application Approach

    Directory of Open Access Journals (Sweden)

    Fetah Kolonic

    2006-10-01

    Full Text Available The Tensor Product (TP model transformation is a recently proposed techniquefor transforming given Linear Parameter Varying (LPV state-space models into polytopicmodel form, namely, to parameter varying convex combination of Linear Time Invariant(LTI systems. The main advantage of the TP model transformation is that it is executablein a few minutes and the Linear Matrix Inequality (LMI-based control design frameworkscan immediately be applied to the resulting polytopc models to yield controllers withtractable and guaranteed performance. Various applications of the TP modeltransformation-based design were studied via academic complex and benchmark problems,but no real experimental environment-based study was published. Thus, the main objectiveof this paper is to study how the TP model transformation performs in a real world problemand control setup. The laboratory concept for TP model-based controller design,simulation and real time running on an electromechanical system is presented.Development system for TP model-based controller with one hardware/software platformand target system with real-time hardware/ software support are connected in the uniquesystem. Proposed system is based on microprocessor of personal computer (PC forsimulation and software development as well as for real-time control. Control algorithm,designed and simulated in MATLAB/SIMULINK environment, use graphically orientedsoftware interface for real-time code generation. Some specific conflicting industrial tasksin real industrial crane application, such as fast load positioning control and load swingangle minimization, are considered and compared with other controller types.

  15. Stereochemistry of reductions catalyzed by methyl-epimerizing ketoreductase domains of polyketide synthases.

    Science.gov (United States)

    You, Young-Ok; Khosla, Chaitan; Cane, David E

    2013-05-22

    Ketoreductase (KR) domains from modular polyketide synthases (PKSs) catalyze the reduction of 2-methyl-3-ketoacyl acyl carrier protein (ACP) substrates and in certain cases epimerization of the 2-methyl group as well. The structural and mechanistic basis of epimerization is poorly understood, and only a small number of such KRs been studied. In this work, we studied three recombinant KR domains with putative epimerase activity: NysKR1 from module 1 of the nystatin PKS, whose stereospecificity can be predicted from both the protein sequence and the product structure; RifKR7 from module 7 of the rifamycin PKS, whose stereospecificity cannot be predicted from the protein sequence; and RifKR10 from module 10 of the rifamycin PKS, whose specificity is unclear from both the sequence and the structure. Each KR was individually incubated with NADPH and (2R)- or (2RS)-2-methyl-3-ketopentanoyl-ACP generated enzymatically in situ or via chemoenzymatic synthesis, respectively. Chiral GC-MS analysis revealed that each KR stereospecifically produced the corresponding (2S,3S)-2-methyl-3-hydroxypentanoyl-ACP in which the 2-methyl substituent had undergone KR-catalyzed epimerization. Thus, our results have led to the identification of a prototypical set of KR domains that generate (2S,3S)-2-methyl-3-hydroxyacyl products in the course of polyketide biosynthesis.

  16. Structure elucidation of hexabromocyclododecanes--a class of compounds with a complex stereochemistry.

    Science.gov (United States)

    Heeb, Norbert V; Schweizer, W Bernd; Kohler, Martin; Gerecke, Andreas C

    2005-09-01

    Hexabromocyclododecanes (HBCDs) are high production volume chemicals (16700 t worldwide in 2001) used as flame-retardants for plastics and textiles. HBCDs exhibit typical properties of persistent organic pollutants (POPs). They are highly lipophilic and accumulate in biota. Increasing environmental concentrations of HBCDs, mostly reported as sum values, have been observed. As such, HBCDs have to be considered as potential emerging POPs, but their occurrence and environmental fate have not yet been addressed at the level of individual HBCD stereoisomers. Considering the six stereogenic centers of HBCDs, 16 stereoisomers, six diastereomeric pairs of enantiomers as well as four meso forms, can be deduced. Herein, we report spectroscopic and chromatographic data for eight out of 16 possible HBCD stereoisomers, which were isolated from a technical product. Six stereoisomers were identified as three pairs of enantiomers ((+/-) alpha-, beta-, and gamma-HBCDs), differing in optical rotation and chromatographic retention on a chiral phase. The crystal structures of these pairs of enantiomers were determined. Another two of these eight HBCD stereoisomers, not yet described in the literature, showed no optical rotation and are tentatively assigned as meso forms (delta- and epsilon-HBCD). The given spectroscopic and chromatographic information allows the unambiguous identification of eight HBCD stereoisomers and the occurrence, fate, and toxicology of these individual stereoisomers can now be studied.

  17. Synthesis of precursors to and spectroscopic characterization of highly unsaturated carbenes and diradicals and development and implementation of a web-based stereochemistry tutorial

    Science.gov (United States)

    Burrmann, Nicola Jean

    A variety of substituted diynols, diynals, and diynones have been prepared en route to the synthesis of precursors to dialkynyl carbenes (R1--C≡C--C--C≡C--R 2). In light of the unique reactivity associated with these simple systems, several strategies were required to assemble the carbon backbones (Chapter I). Tosylhydrazone and trisylhydrazone precursors to 2-diazo-3-pentyne ( 1), 2-diazo-3-butyne (2), and Idiazo-2-butyne ( 3) were synthesized and then converted into their respective diazo compounds. Various attempts to study these diazo compounds using matrix isolation IR and EPR spectroscopy were made and proved to be unsuccessful. Computations were done to characterize the C5H6 potential energy surface, as well as to determine the IR vibrational frequencies of the isomers on this surface (Chapter 2). A web-based Stereochemistry Tutorial that details the core definitions and structural representations relevant to organic stereochemistry was designed and implemented into several introductory-level organic chemistry classes. This tutorial also allows for students to select their preferred structural representation and method for making stereochemical comparisons between molecules. The tutorial was evaluated, either qualitatively, quantitatively, or both, by students in three different introductory organic chemistry courses at the University of Wisconsin---Madison. The data show that students did use a variety of different methods for making stereochemical comparisons between molecules, and that prior exposure to lectures on stereochemistry by the course professor strongly influenced these choices. Furthermore, the level of improvement in stereochemical knowledge as a result of using only the tutorial was comparable to, or higher than, that achieved by students who were only exposed to lectures by the course professor, regardless of the method chosen for making stereochemical comparisons between molecules (Chapter 3)

  18. Initial Flight Test of the Production Support Flight Control Computers at NASA Dryden Flight Research Center

    Science.gov (United States)

    Carter, John; Stephenson, Mark

    1999-01-01

    The NASA Dryden Flight Research Center has completed the initial flight test of a modified set of F/A-18 flight control computers that gives the aircraft a research control law capability. The production support flight control computers (PSFCC) provide an increased capability for flight research in the control law, handling qualities, and flight systems areas. The PSFCC feature a research flight control processor that is "piggybacked" onto the baseline F/A-18 flight control system. This research processor allows for pilot selection of research control law operation in flight. To validate flight operation, a replication of a standard F/A-18 control law was programmed into the research processor and flight-tested over a limited envelope. This paper provides a brief description of the system, summarizes the initial flight test of the PSFCC, and describes future experiments for the PSFCC.

  19. N-benzoyl-1,5-benzothiazepine and its S-oxide as vasopressin receptor ligands: insight into the active stereochemistry around the seven-membered ring.

    Science.gov (United States)

    Yoneda, Tetsuya; Tabata, Hidetsugu; Tasaka, Tomohiko; Oshitari, Tetsuta; Takahashi, Hideyo; Natsugari, Hideaki

    2015-04-09

    The stereochemistry of N-benzoyl-1,5-benzothiazepine and its S-oxide derivatives as vasopressin receptor ligands was examined in detail by freezing the conformation with a methyl group at the C6 or C9 of 1,5-benzothiazepine. It was revealed that the active forms recognized by the receptors are (cis,aS) for 1,5-benzothiazepine (5-7)-II and (cis,1S,aS) (syn) for its S-oxide (8-10)-II. The C9-methyl derivative of 1,5-benzothiazepine S-oxide (10-II) was designed and synthesized, achieving the putative active syn-isomer.

  20. Importance of permanent improvement of production and control of basic seed of ZP maize hybrids

    Directory of Open Access Journals (Sweden)

    Sečanski Mile

    2015-01-01

    Full Text Available High-quality seed is one of the key factors in the commercial maize grain production. In addition, hybrid seed production is conditioned by the production of basic seed of parental inbreds. According to the Law on Seed, 2005, the category of basic seed is defined as: original of self-pollinated plant species, hybrid components and potato elite, produced under control of the Ministry competent for agribusiness and is used for the production of certified seed of the first generation. This paper presents a chronological overview of the overall activity since1945. that led to the modern production of maize seed in our country. The activities have been based on scientific, technical and technological achievements within many fields, ranging from genetics and breeding, through growing practices, processing, quality control and legal regulations concerning all of this. Transition from maize breeding and production to hybrids has provided an amazing development of maize breeding and seed production and also included significant profit. Therefore, maize seed production has become high-technology industry. The scientific and professional work in improving the production of basic seed of ZP maize hybrids has been carried out in stages, and generally followed achievements in maize breeding and genetics, as well as developments in the growing practices and processing. In order to maintain a high quality of maize hybrid seed, as the end product, permanent efforts have to be invested into maize production improvement, drying, processing, storing, genetic purity of basic seed of parental inbreds of ZP maize hybrids, which are grown on the significant percentage of maize production areas not only in Serbia and countries in the region.

  1. Dust control products at Hagerman National Wildlife Refuge, Texas: environmental safety and performance

    Science.gov (United States)

    Kunz, Bethany K.; Little, Edward E.

    2015-01-01

    Controlling fugitive dust while protecting natural resources is a challenge faced by all managers of unpaved roads. Unfortunately, road managers choosing between dust control products often have little objective environmental information to aid their decisions. To address this information gap, the U.S. Geological Survey and the U.S. Fish and Wildlife Service collaborated on a field test of three dust control products with the objectives of (a) evaluating product performance under real-world conditions, (b) verifying the environmental safety of products identified as practically nontoxic in laboratory tests, and (c) testing the feasibility of several environmental monitoring techniques for use in dust control tests. In cooperation with refuge staff and product vendors, three products (one magnesium chloride plus binder, one cellulose, and one synthetic fluid plus binder) were applied in July 2012 to replicated road sections at the Hagerman National Wildlife Refuge in Texas. These sections were monitored periodically for 12 months after application. Product performance was assessed by mobile-mounted particulate-matter meters measuring production of fugitive dust and by observations of road conditions. Environmental safety was evaluated through on-site biological observations and leaching tests with samples of treated aggregate. All products reduced dust and improved surface condition during those 12 months. Planned environmental measurements were not always compatible with day-to-day refuge management actions; this incompatibility highlighted the need for flexible biological monitoring plans. As one of the first field tests of dust suppressants that explicitly incorporated biological endpoints, this effort provides valuable information for improving field tests and for developing laboratory or semifield alternatives.

  2. [Investigation on production process quality control of traditional Chinese medicine--Banlangen granule as an example].

    Science.gov (United States)

    Tan, Manrong; Yan, Dan; Qiu, Lingling; Chen, Longhu; Yan, Yan; Jin, Cheng; Li, Hanbing; Xiao, Xiaohe

    2012-04-01

    For the quality management system of herbal medicines, intermediate and finished products it exists the " short board" effect of methodologies. Based on the concept of process control, new strategies and new methods of the production process quality control had been established with the consideration of the actual production of traditional Chinese medicine an the characteristics of Chinese medicine. Taking Banlangen granule as a practice example, which was effective and widespread application, character identification, determination of index components, chemical fingerprint and biometrics technology were sequentially used respectively to assess the quality of Banlangen herbal medicines, intermediate (water extraction and alcohol precipitation) and finished product. With the transfer rate of chemical information and biological potency as indicators, the effectiveness and transmission of the above different assessments and control methods had been researched. And ultimately, the process quality control methods of Banlangen granule, which were based on chemical composition analysis-biometric analysis, had been set up. It can not only validly solute the current status that there were many manufacturers varying quality of Banlangen granule, but also ensure and enhance its clinical efficacy. Furthermore it provided a foundation for the construction of the quality control of traditional Chinese medicine production process.

  3. Elucidating the Stereochemistry of Enzymatic Benzylsuccinate Synthesis with Chirally Labeled Toluene.

    Science.gov (United States)

    Seyhan, Deniz; Friedrich, Peter; Szaleniec, Maciej; Hilberg, Markus; Buckel, Wolfgang; Golding, Bernard T; Heider, Johann

    2016-09-12

    Benzylsuccinate synthase is a glycyl radical enzyme that initiates anaerobic toluene metabolism by adding fumarate to the methyl group of toluene to yield (R)-benzylsuccinate. To investigate whether the reaction occurs with retention or inversion of configuration at the methyl group of toluene, we synthesized both enantiomers of chiral toluene with all three H isotopes in their methyl groups. The chiral toluenes were converted into benzylsuccinates preferentially containing (2) H and (3) H at their benzylic C atoms, owing to a kinetic isotope effect favoring hydrogen abstraction from the methyl groups. The configuration of the products was analyzed by enzymatic CoA-thioester synthesis and stereospecific oxidation using enzymes involved in benzylsuccinate degradation. Assessment of the configurations of the benzylsuccinate isomers based on loss or retention of tritium showed that inversion of configuration at the methyl group occurs when the chiral toluenes react with fumarate.

  4. Research on Production Process Control Method Combined Stochastic Process Algebra and Stochastic Petri Nets

    Institute of Scientific and Technical Information of China (English)

    LIU Chang; SHI Haibo

    2006-01-01

    A hierarchical closed-loop production control scheme integrating scheduling, control and performance evaluation is discussed. Firstly, the production process is divided into two main hierarchies: the lower level is the physical operation level and the upper one is the management level. Secondly, the schedule template for the management level and the activity template for the physical operation level are constructed separately, the tasks in the schedule have the ability to make partial decisions, and the performance parameters are introduced into activity template. Thirdly, the two levels use different model representations: stochastic process algebra for the management level whose output is the control commands and stochastic Petri net for the physical operation level which is the execution of the control commands. Then, the integration of the two levels is the control commands mapping into the lower physical operations and the responses feeding back to the upper decision-making that are defined by some transition functions. Under the proposed scheme, the production process control of a flexible assembly is exemplified. It is concluded that the process control model has partial ability to make decision on-line for uncertain and dynamic environments and facilitates reasoning about the behaviors of the process control, and performance evaluation can be done online for real-time scheduling to ensure the global optimization.

  5. Functional Connectivity Reveals Which Language the “Control Regions” Control during Bilingual Production

    Science.gov (United States)

    Li, Le; Emmorey, Karen; Feng, Xiaoxia; Lu, Chunming; Ding, Guosheng

    2016-01-01

    Bilingual studies have revealed critical roles for the dorsal anterior cingulate cortex (dACC) and the left caudate nucleus (Lcaudate) in controlling language processing, but how these regions manage activation of a bilingual’s two languages remains an open question. We addressed this question by identifying the functional connectivity (FC) of these control regions during a picture-naming task by bimodal bilinguals who were fluent in both a spoken and a signed language. To quantify language control processes, we measured the FC of the dACC and Lcaudate with a region specific to each language modality: left superior temporal gyrus (LSTG) for speech and left pre/postcentral gyrus (LPCG) for sign. Picture-naming occurred in either a single- or dual-language context. The results showed that in a single-language context, the dACC exhibited increased FC with the target language region, but not with the non-target language region. During the dual-language context when both languages were alternately the target language, the dACC showed strong FC to the LPCG, the region specific to the less proficient (signed) language. By contrast, the Lcaudate revealed a strong connectivity to the LPCG in the single-language context and to the LSTG (the region specific to spoken language) in the dual-language context. Our findings suggest that the dACC monitors and supports the processing of the target language, and that the Lcaudate controls the selection of the less accessible language. The results support the hypothesis that language control processes adapt to task demands that vary due to different interactional contexts. PMID:27965563

  6. Functional connectivity reveals which language the “control regions” control during bilingual production

    Directory of Open Access Journals (Sweden)

    Le Li

    2016-11-01

    Full Text Available Bilingual studies have revealed critical roles for the dorsal anterior cingulate cortex (dACC and the left caudate nucleus (Lcaudate in controlling language processing, but how these regions manage activation of a bilingual’s two languages remains an open question. We addressed this question by identifying the functional connectivity (FC of these control regions during a picture-naming task by bimodal bilinguals who were fluent in both a spoken and a signed language. To quantify language control processes, we measured the FC of the dACC and Lcaudate with a region specific to each language modality: left superior temporal gyrus (LSTG for speech and left pre/postcentral gyrus (LPCG for sign. Picture-naming occurred in either a single- or dual-language context. The results showed that in a single-language context, the dACC exhibited increased FC with the target language region, but not with the non-target language region. During the dual-language context when both languages were alternately the target language, the dACC showed strong FC to the LPCG, the regions specific to the less proficient (signed language. By contrast, the Lcaudate revealed strong connectivity to the LPCG in the single-language context and to the LSTG (the region specific to spoken language in the dual-language context. Our findings suggest that the dACC monitors and supports the processing of the target language, and that the Lcaudate controls the selection of the less accessible language. The results support the hypothesis that language control processes adapt to task demands that vary due to different interactional contexts.

  7. Lesions to lateral prefrontal cortex impair interference control in word production

    Directory of Open Access Journals (Sweden)

    Vitória ePiai

    2016-01-01

    Full Text Available Speaking is an action that requires control, for example, to prevent interference from distracting or competing information present in the speaker’s environment. Control over task performance is thought to depend on the lateral prefrontal cortex (PFC. However, the neuroimaging literature does not show a consistent relation between left PFC and interference control in word production. Here, we examined the role of left PFC in interference control in word production by testing six patients with lesions to left PFC (centred around the ventrolateral PFC on a control-demanding task. Patients and age-matched controls named pictures presented along with distractor words, inducing within-trial interference effects. We varied the degree of competing information from distractors to increase the need for interference control. Distractors were semantically related, phonologically related, unrelated to the picture name, or neutral (XXX. Both groups showed lexical interference (slower responses with unrelated than neutral distractors, reflecting naming difficulty in the presence of competing linguistic information. Relative to controls, all six left PFC patients had larger lexical interference effects. By contrast, patients did not show a consistent semantic interference effect (reflecting difficulty in selecting amongst semantic competitors whereas the controls did. This suggests different control mechanisms may be engaged in semantic compared to lexical interference resolution in this paradigm. Finally, phonological facilitation (faster responses with phonological than unrelated distractors was larger in patients than in controls. These findings suggest that the lateral PFC is a necessary structure in providing control over lexical interference in word production, possibly through an early attentional blocking mechanism. By contrast, the left PFC does not seem critical in semantic interference resolution in the picture-word interference paradigm.

  8. Product market competition,ultimate controlling structure and related party transactions

    Institute of Scientific and Technical Information of China (English)

    Shenglan Chen; Kun Wang; Xiaoxue Li

    2012-01-01

    Previous studies have shown that product market competition has an important effect on corporate strategies and internal governance mechanisms. Using a sample of China’s listed firms from 2004 to 2009, we explore the relationship between product market competition and normal related party transactions and find a significant positive relationship. In addition, we investigate the substitutive effect of product market competition and the cash flow rights owned by ultimate controlling shareholders on the extent of normal related party transactions. In particular, our results suggest a positive relationship between the ultimate controlling shareholders’ cash flow rights and normal related party transactions that is strongest in noncompetitive industries and weakens as product market competition increases.

  9. Control of public expenditure on drug products in Bulgaria – Policies and outcomes

    Directory of Open Access Journals (Sweden)

    Toni Yonkov Vekov

    2015-12-01

    implementing agreements on controlled access of patients after June 2009. This led to an annual increase in the expenditures on drug products for home treatment (on average, 17% for the period 2009-2012. Conclusion: This trend in Bulgaria will continue in the future since expenditure control only through price control by means of a reference system and the positive list of medicines is ineffective. There is a need for implementation of combined drug policies in Bulgaria in the form of negotiations on rebates with manufacturers and agreements on controlled access of patients and reference pricing.

  10. Improvement of L: -Lactic Acid Production under Glucose Feedback Controlled Culture by Lactobacillus rhamnosus.

    Science.gov (United States)

    Li, Zheng; Lu, JiKe; Zhao, Liqiang; Xiao, Kai; Tan, Tianwei

    2010-11-01

    In this study, a glucose feedback controller had been designed. Under the controller, the glucose concentration in l-lactic acid culture could be automatically controlled at 15 ± 1 g/L. Furthermore, l-lactic acid production by Lactobacillus rhamnosus LA-04-1 in fed-batch culture was significantly increased to 170 g/L l-lactic acid using the controller compared with 130 g/L l-lactic acid in pulse fed-batch and 135 g/L in l-lactic acid constant feed rate fed-batch cultures. The results showed that the controller was effective at glucose control in l-lactic acid culture. The control strategy could also be used in other fermentation processes.

  11. Stereochemistry and thermal stability of tartaric acid on the intrinsically chiral Cu{531} surface

    Science.gov (United States)

    Baldanza, Silvia; Ardini, Jacopo; Giglia, Angelo; Held, Georg

    2016-01-01

    Intrinsically chiral metal surfaces provide enantiospecific reaction environments without the need of co-adsorbed modifiers. Amongst the intrinsically chiral copper surfaces, Cu{531} has the smallest unit cell and the highest density of chiral sites. XPS, NEXAFS and TPD were employed to investigate the adsorption and decomposition behaviour of the two chiral enantiomers of tartaric acid on this surface. The results obtained from XPS and NEXAFS show that at saturation coverage both enantiomers of tartaric acid adsorb in a μ4 configuration through the two carboxylic groups, which are rotated with respect to each other by 90° ± ≈ 15° within the surface plane. At intermediate coverage the R,R enantiomer adopts a similar configuration, but the S,S enantiomer is different and shows a high degree of dissociation. Growth of multilayers is observed at high exposures when the sample is kept at below 370 K. TPD experiments show that multilayers desorb between 390 K and 470 K and decomposition of the chemisorbed layer occurs between 470 K and 600 K. The desorption spectra support a two-step decomposition mechanism with a Odbnd Cdbnd Cdbnd O or HO-HCdbnd CH-OH intermediate that leads to production of CO2 and CO. Enantiomeric differences are observed in the desorption features related to the decomposition of the chemisorbed layer.

  12. Production control in the steel industry with energy conservation considerations: a preliminary evaluation. [GASP

    Energy Technology Data Exchange (ETDEWEB)

    Takamoto, H.; Williams, T.J.

    1979-06-01

    The work here consists mainly of three tasks; the first is to construct the basic production model for the raw-material preparation and the iron-making area which had been ignored in the earlier work, but is vital to the energy problem. The second is to construct the energy utilization and energy generation models over all the steel production units involved in the plant. The third is to develop the hierarchy structure to control the energy management function.

  13. Simulation model for improved production planning and control through quality, cycle time and batch size management

    OpenAIRE

    Kotevski Živko; Jovanoski Bojan; Minovski Robert

    2015-01-01

    Production planning and control (PPC) systems are the base of all production facilities. In today's surroundings, having a good PPC system generates lots of benefits for the companies. But, having an excellent PPC system provides great competitive advantage and serious reduction of cost in many fields. In order to get to a point of having excellent PPC, the companies turn more and more to the newest software tools, for simulations as an example. Considering today's advanced computer technolog...

  14. LHC-GCS a framework for the production of 23 homogeneous control systems

    CERN Document Server

    Thomas, Geraldine; Barillère, Renaud; Cabaret, Sebastien; Kulman, Nikolay; Pons, Xavier; Rochez, Jacques

    2005-01-01

    The LHC experiments’ Gas Control System (LHC GCS) aims to provide the LHC experiments with homogeneous control systems (supervision and process control layers) for their 23 gas systems. To ease the production of these control systems, it has been decided to develop a library of components, the LHC GCS framework, and to adopt a model-driven automatic code generation approach. The first milestones of the project have been achieved. The components of the LHC GCS framework have been developed as well as the code generation tools. A first control application has been built and put into production, a second is in preparation. This paper describes the components which have been developed to ease the production of the supervision and process control layers of the control applications. It identifies in particular the additions and extensions to the UNICOS libraries and how the framework could be re-used for other applications. The paper also explains how the LHC GCS framework is associated with the LHC GCS automatic...

  15. Control of Listeria species food safety at a poultry food production facility.

    Science.gov (United States)

    Fox, Edward M; Wall, Patrick G; Fanning, Séamus

    2015-10-01

    Surveillance and control of food-borne human pathogens, such as Listeria monocytogenes, is a critical aspect of modern food safety programs at food production facilities. This study evaluated contamination patterns of Listeria species at a poultry food production facility, and evaluated the efficacy of procedures to control the contamination and transfer of the bacteria throughout the plant. The presence of Listeria species was studied along the production chain, including raw ingredients, food-contact, non-food-contact surfaces, and finished product. All isolates were sub-typed by pulsed-field gel electrophoresis (PFGE) to identify possible entry points for Listeria species into the production chain, as well as identifying possible transfer routes through the facility. The efficacy of selected in-house sanitizers against a sub-set of the isolates was evaluated. Of the 77 different PFGE-types identified, 10 were found among two or more of the five categories/areas (ingredients, food preparation, cooking and packing, bulk packing, and product), indicating potential transfer routes at the facility. One of the six sanitizers used was identified as unsuitable for control of Listeria species. Combining PFGE data, together with information on isolate location and timeframe, facilitated identification of a persistent Listeria species contamination that had colonized the facility, along with others that were transient.

  16. Pharmaceutical quality by design: product and process development, understanding, and control.

    Science.gov (United States)

    Yu, Lawrence X

    2008-04-01

    The purpose of this paper is to discuss the pharmaceutical Quality by Design (QbD) and describe how it can be used to ensure pharmaceutical quality. The QbD was described and some of its elements identified. Process parameters and quality attributes were identified for each unit operation during manufacture of solid oral dosage forms. The use of QbD was contrasted with the evaluation of product quality by testing alone. The QbD is a systemic approach to pharmaceutical development. It means designing and developing formulations and manufacturing processes to ensure predefined product quality. Some of the QbD elements include: Defining target product quality profile; Designing product and manufacturing processes; Identifying critical quality attributes, process parameters, and sources of variability; Controlling manufacturing processes to produce consistent quality over time. Using QbD, pharmaceutical quality is assured by understanding and controlling formulation and manufacturing variables. Product testing confirms the product quality. Implementation of QbD will enable transformation of the chemistry, manufacturing, and controls (CMC) review of abbreviated new drug applications (ANDAs) into a science-based pharmaceutical quality assessment.

  17. A comparison of push and pull production controls under machine breakdown

    Directory of Open Access Journals (Sweden)

    Prakash, J.

    2011-01-01

    Full Text Available Production control for high-mix production remains a complex issue. Common pull system replenishment generates large works-in-process (WIPs for each part type, especially under breakdown. This paper attempts to solve this by presenting a production control that classifies parts into two categories. The performances of three production control mechanisms under breakdown are compared. The production control mechanisms in consideration are push, shared constant WIP (CONWIP, and parallel CONWIP. A full-factorial simulation experiment was conducted. ANOVA was performed to determine the significant effects of input factors. Response surface methodology was used to demonstrate the behavior of performance measures in terms of these significant input factors. The results prove that parallel CONWIP is superior over shared CONWIP in terms of the average flow time per part. If categorical dispatch rules are employed, parallel CONWIP outperforms shared CONWIP in terms of service level. With high card count, parallel CONWIP generally produces lower bottleneck utilizations while maintaining a low average flow time per part than shared CONWIP.

  18. Quantifying controlled productive knowledge of collocations across proficiency and word frequency levels

    Directory of Open Access Journals (Sweden)

    Déogratias Nizonkiza

    2012-10-01

    Full Text Available The present study explores the relationship between controlled productive knowledge of collocations and L2 proficiency, the role of frequency in controlled productive knowledge of collocations, and the quantifiability of controlled productive collocational knowledge growth alongside L2 proficiency and word frequency levels. A proficiency measure and a productive collocation test modelled on Laufer and Nation (1999 were presented to Belgian and Burundian English majors. The results show that scores on both tests distinguish between proficiency levels and, furthermore, highly correlate. This suggests that controlled productive knowledge of collocations develops as proficiency increases, supporting earlier studies (Boers, Eyckmans, Kappel, Stengers, & Demecheleer, 2006; Bonk, 2001; Eyckmans, Boers, & Demecheleer, 2004; Gitsaki, 1999 that had established a relationship between collocational knowledge and L2 proficiency. The results also show that the more frequent the collocations, the better they are known, which highlights the crucial role played by frequency in knowing words (Nation & Beglar, 2007. Furthermore, the number of collocations added can be quantified and we observe moderat egains at beginner and advanced levels, and impressive gains at intermediate levels. This supports and extends Laufer’s (1998 and Zhong and Hirsh’s (2009 findings and lays basic ground work for teaching collocations, the amount of which should increase with proficiency levels.

  19. Syringeal specialization of frequency control during song production in the Bengalese finch (Lonchura striata domestica).

    Science.gov (United States)

    Secora, Kristen R; Peterson, Jennifer R; Urbano, Catherine M; Chung, Boah; Okanoya, Kazuo; Cooper, Brenton G

    2012-01-01

    Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx) has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production) and rapid switching between left and right sound generation (interhemispheric switching of motor control). Bengalese finches (Lonchura striata domestica) have received considerable attention, because they rapidly modify their song in response to manipulations of auditory feedback. However, how the left and right sides of the syrinx contribute to acoustic control of song has not been studied. Three manipulations of lateralized syringeal control of sound production were conducted. First, unilateral syringeal muscular control was eliminated by resection of the left or right tracheosyringeal portion of the hypoglossal nerve, which provides neuromuscular innervation of the syrinx. Spectral and temporal features of song were compared before and after lateralized nerve injury. In a second experiment, either the left or right sound source was devoiced to confirm the role of each sound generator in the control of acoustic phonology. Third, air pressure was recorded before and after unilateral denervation to enable quantification of acoustic change within individual syllables following lateralized nerve resection. These experiments demonstrate that the left sound source produces louder, higher frequency, lower entropy sounds, and the right sound generator produces lower amplitude, lower frequency, higher entropy sounds. The bilateral division of labor is complex and the frequency specialization is the opposite pattern observed in most songbirds. Further, there is evidence for rapid interhemispheric switching during song production. Lateralized control of song production in Bengalese finches may enhance acoustic complexity of song

  20. Syringeal specialization of frequency control during song production in the Bengalese finch (Lonchura striata domestica.

    Directory of Open Access Journals (Sweden)

    Kristen R Secora

    Full Text Available BACKGROUND: Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production and rapid switching between left and right sound generation (interhemispheric switching of motor control. Bengalese finches (Lonchura striata domestica have received considerable attention, because they rapidly modify their song in response to manipulations of auditory feedback. However, how the left and right sides of the syrinx contribute to acoustic control of song has not been studied. METHODOLOGY: Three manipulations of lateralized syringeal control of sound production were conducted. First, unilateral syringeal muscular control was eliminated by resection of the left or right tracheosyringeal portion of the hypoglossal nerve, which provides neuromuscular innervation of the syrinx. Spectral and temporal features of song were compared before and after lateralized nerve injury. In a second experiment, either the left or right sound source was devoiced to confirm the role of each sound generator in the control of acoustic phonology. Third, air pressure was recorded before and after unilateral denervation to enable quantification of acoustic change within individual syllables following lateralized nerve resection. SIGNIFICANCE: These experiments demonstrate that the left sound source produces louder, higher frequency, lower entropy sounds, and the right sound generator produces lower amplitude, lower frequency, higher entropy sounds. The bilateral division of labor is complex and the frequency specialization is the opposite pattern observed in most songbirds. Further, there is evidence for rapid interhemispheric switching during song production. Lateralized control of song production in

  1. Methane emissions from process equipment at natural gas production sites in the United States: pneumatic controllers.

    Science.gov (United States)

    Allen, David T; Pacsi, Adam P; Sullivan, David W; Zavala-Araiza, Daniel; Harrison, Matthew; Keen, Kindal; Fraser, Matthew P; Daniel Hill, A; Sawyer, Robert F; Seinfeld, John H

    2015-01-06

    Emissions from 377 gas actuated (pneumatic) controllers were measured at natural gas production sites and a small number of oil production sites, throughout the United States. A small subset of the devices (19%), with whole gas emission rates in excess of 6 standard cubic feet per hour (scf/h), accounted for 95% of emissions. More than half of the controllers recorded emissions of 0.001 scf/h or less during 15 min of measurement. Pneumatic controllers in level control applications on separators and in compressor applications had higher emission rates than controllers in other types of applications. Regional differences in emissions were observed, with the lowest emissions measured in the Rocky Mountains and the highest emissions in the Gulf Coast. Average methane emissions per controller reported in this work are 17% higher than the average emissions per controller in the 2012 EPA greenhouse gas national emission inventory (2012 GHG NEI, released in 2014); the average of 2.7 controllers per well observed in this work is higher than the 1.0 controllers per well reported in the 2012 GHG NEI.

  2. Production and Quality Control of Micromegas Anode PCBs for the ATLAS NSW Upgrade

    CERN Document Server

    Kuger, Fabian; The ATLAS collaboration

    2016-01-01

    For the 2019-20 New Small Wheel upgrade of the ATLAS detector, Micromegas detectors of 1280m2 active area will be build. On this scale industrialization of anode board production is an essential precondition for detector construction. Design and construction methods of these boards have been optimized towards mass production. In parallel quality control procedures have been developed and established. The first pre-series of large size Micromegas anode boards has been produced in industries during 2015 and demonstrates the feasibility of the project. Full scale production is currently launching and will last 16 months.

  3. A Dynamic Bayesian Network Model for the Production and Inventory Control

    Science.gov (United States)

    Shin, Ji-Sun; Takazaki, Noriyuki; Lee, Tae-Hong; Kim, Jin-Il; Lee, Hee-Hyol

    In general, the production quantities and delivered goods are changed randomly and then the total stock is also changed randomly. This paper deals with the production and inventory control using the Dynamic Bayesian Network. Bayesian Network is a probabilistic model which represents the qualitative dependence between two or more random variables by the graph structure, and indicates the quantitative relations between individual variables by the conditional probability. The probabilistic distribution of the total stock is calculated through the propagation of the probability on the network. Moreover, an adjusting rule of the production quantities to maintain the probability of a lower limit and a ceiling of the total stock to certain values is shown.

  4. A Software Architecture for Control of Value Production in Federated Systems

    Directory of Open Access Journals (Sweden)

    Jay S. Bayne

    2003-08-01

    Full Text Available Federated enterprises are defined as interactive commercial entities that produce products and consume resources through a network of open, free-market transactions. Value production in such entities is defined as the real-time computation of enterprise value propositions. These computations are increasingly taking place in a grid-connected space – a space that must provide for secure, real-time, reliable end-to-end transactions governed by formal trading protocols. We present the concept of a value production unit (VPU as a key element of federated trading systems, and a software architecture for automation and control of federations of such VPUs.

  5. BUSINESS PROCESS MODELING AND PRODUCTION CONTROL SYSTEM SPECIFICATION IN THE SELF-ADHESIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Marcos Ricardo Rosa Georges

    2010-12-01

    Full Text Available This article presents the development of an information system for production control in an industry of self-adhesive products. The option to develop their own information system is due to the high specificity of their production system and unsuccessful attempt to adopt ERP systems available. The development of the intended information system was based on the modeling of all businesses processes throughout production, recognizing all data, processes and people involved, and especially the flow of information and decisions made during production. This body of information raised through the modeling of businesses processes enabled the specification of the structure of the data contained in every notation form from the shop floor, as well as the definition of access screens for all reports, and data manipulations required for production. By using a database, spreadsheets and some microcomputers interconnected in a network, a production control system was implemented on the shop-floor six months after the beginning of the system development. Details of the businesses processes modeled, of the data structure and of all flows are presented in this article. Comments on the results complete this study.

  6. Agents Modeling Experience Applied To Control Of Semi-Continuous Production Process

    Directory of Open Access Journals (Sweden)

    Gabriel Rojek

    2014-01-01

    Full Text Available The lack of proper analytical models of some production processes prevents us from obtaining proper values of process parameters by simply computing optimal values. Possible solutions of control problems in such areas of industrial processes can be found using certain methods from the domain of artificial intelligence: neural networks, fuzzy logic, expert systems, or evolutionary algorithms. Presented in this work, a solution to such a control problem is an alternative approach that combines control of the industrial process with learning based on production results. By formulating the main assumptions of the proposed methodology, decision processes of a human operator using his experience are taken into consideration. The researched model of using and gathering experience of human beings is designed with the contribution of agent technology. The presented solution of the control problem coincides with case-based reasoning (CBR methodology.

  7. Production of Leuconostoc oenos Biomass under pH Control

    Science.gov (United States)

    Champagne, Claude P.; Gardner, Nancy; Doyon, Gilles

    1989-01-01

    Leuconostoc oenos was grown on apple juice-based media. The effect of pH control on metabolism and biomass production was studied. Without pH control, L. oenos acidified the apple juice media to approximately pH 3.6. More than 75% of the malic acid was used under these conditions, but less than half of the carbohydrates was assimilated. Under pH control, biomass yields increased by 60%; most of the malic acid was used, but high levels of unfermented carbohydrates remained. The addition of tomato juice, vitamins, nucleotides, Mn+, and malic acid did not permit further increases in the cell counts; however, malic acid did induce further acidification. Growth without pH control favored a more homofermentative metabolism. Biomass production was higher in filter-sterilized apple juice media compared with that in the autoclaved media. PMID:16348025

  8. Control of cheese quality – strategies and methods for delivery of consistent sensory product quality at the point of consumption

    OpenAIRE

    Kraggerud, Hilde

    2011-01-01

    An effective approach to quality control is an important issue for a food producer, as consumers expect consistent delivery of products. Two important strategies for control of food product end quality was discussed in this thesis: Process regulation and Statistical Process control (SPC). Extensive experiments were carried out in order to demonstrate different aspects of control of cheese quality. The sensory quality of a product is of great importance, as it is directly perceived at consu...

  9. Process control strategy of the silicon sensors production for the CMS tracker

    CERN Document Server

    Fontaine, J C; Helleboid, J M; Krammer, M; Macchiolo, A

    2002-01-01

    In the framework of the CMS experiment, a quality control of the silicon sensors production has been developed for the tracker construction. The emphasis here is on the process stability control based on the characterization of test-structures made of eight different components. The measurements carried out are presented. Then the set-up and the software developed for this purpose are explained. The first results, including the ones obtained on faulty batches of sensors, are shown.

  10. Credit risk control for loan products in commercial banks. Case: BIDV

    OpenAIRE

    Nguyen, Linh

    2017-01-01

    In the world of banking, competition between commercial banks is increasing more and more. Lenders are trying to satisfy customers in various credit services, which include lending services. To keep themselves in the play, banks focus on improving credit growth. However, higher credit growth will not truly bring higher profits if banks fail to manage credit risk. This thesis studies credit risk control for business loan products and aims to identify different approaches to control the risk ef...

  11. Alcohol-, diol-, and carbohydrate-substituted indenoisoquinolines as topoisomerase I inhibitors: investigating the relationships involving stereochemistry, hydrogen bonding, and biological activity.

    Science.gov (United States)

    Peterson, Katherine E; Cinelli, Maris A; Morrell, Andrew E; Mehta, Akhil; Dexheimer, Thomas S; Agama, Keli; Antony, Smitha; Pommier, Yves; Cushman, Mark

    2011-07-28

    The DNA-relaxing enzyme topoisomerase I (Top1) can be inhibited by heterocyclic compounds such as indolocarbazoles and indenoisoquinolines. Carbohydrate and hydroxyl-containing side chains are essential for the biological activity of indolocarbazoles. The current study investigated how similar functionalities could be "translated" to the indenoisoquinoline system and how stereochemistry and hydrogen bonding affect biological activity. Herein is described the preparation and assay of indenoisoquinolines substituted with short-chain alcohols, diols, and carbohydrates. Several compounds (including those derived from sugars) display potent Top1 poisoning and antiproliferative activities. The Top1 poisoning activity of diol-substituted indenoisoquinolines is dependent upon stereochemistry. Although the effect is striking, molecular modeling and docking studies do not indicate any reason for the difference in activity due to similar calculated interactions between the ligand and Top1-DNA complex and ambiguity about the binding mode. A stereochemical dependence was also observed for carbohydrate-derived indenoisoquinolines. Although similar trends were observed in other classes of Top1 inhibitors, the exact nature of this effect has yet to be elucidated.

  12. Cork suberin molecular structure: stereochemistry of the C18 epoxy and vic-diol ω-hydroxyacids and α,ω-diacids analyzed by NMR.

    Science.gov (United States)

    Santos, Sara; Cabral, Vanessa; Graça, José

    2013-07-24

    Suberin is the biopolyester that protects the secondary tissues of plants against environmental variability and aggressions. Cork suberin is composed mostly of C18 ω-hydroxyacids and α,ω-diacids, 9,10-substituted with an unsaturation, an epoxide ring, or a vic-diol group. Although determinant for suberin macromolecular structure, the stereochemistry of these monomers is poorly studied, sometimes with contradictory results. An NMR technique was used here to assign the configuration of the 9,10-epoxy and 9,10-diol groups in C18 suberin acids, comparing the chemical shifts of diagnostic (1)H and (13)C signals with the ones of model compounds, before and after conversion of the vic-diol group into benzylidene acetal derivatives. The relative configuration was proved to be cis in the C18 9,10-epoxy and threo in the C18 9,10-diol suberin acids. These monomers were present in suberin probably as racemic mixtures, as shown by polarimetry. The revealed stereochemistry allows the suberin macromolecule to be built as an ordered array of midchain kinked C18 acids, reinforced by intramolecular hydrogen bonding.

  13. Correlations among experimental and theoretical NMR data to determine the absolute stereochemistry of darcyribeirine, a pentacyclic indole alkaloid isolated from Rauvolfia grandiflora

    Science.gov (United States)

    Cancelieri, Náuvia Maria; Ferreira, Thiago Resende; Vieira, Ivo José Curcino; Braz-Filho, Raimundo; Piló-Veloso, Dorila; Alcântara, Antônio Flávio de Carvalho

    2015-10-01

    Darcyribeirine (1) is a pentacyclic indole alkaloid isolated from Rauvolfia grandiflora. Stereochemistry of 1 was previously proposed based on 1D (coupling constant data) and 2D (NOESY correlations) NMR techniques, having been established a configuration 3R, 15S, and 20R (isomer 1a). Stereoisomers of 1 (i.e., 1a-1h) can be grouped into four sets of enantiomers. Carbon chemical shifts and hydrogen coupling constants were calculated using BLYP/6-31G* theory level for the eight isomers of 1. Calculated NMR data of 1a-1h were correlated with the corresponding experimental data of 1. The best correlations between theoretical and experimental carbon chemical shift data were obtained for the set of enantiomers 1e/1f to structures in the gaseous phase and considering solvent effects (using PCM and explicit models). Similar results were obtained when the same procedure was performed to correlations between theoretical and experimental coupling constant data. Finally, optical rotation calculations indicate 1e as its absolute stereochemistry. Orbital population analysis indicates that the hydrogen bonding between N-H of 1e and DMSO is due to contributions of its frontier unoccupied molecular orbitals, mainly LUMO+1, LUMO+2, and LUMO+3.

  14. Stereochemistry and molecular pharmacology of (S)-thio-ATPA, a new potent and selective GluR5 agonist.

    Science.gov (United States)

    Stensbøl, T B; Jensen, H S; Nielsen, B; Johansen, T N; Egebjerg, J; Frydenvang, K; Krogsgaard-Larsen, P

    2001-01-12

    (RS)-2-Amino-3-(5-tert-butyl-3-hydroxy-4-isothiazolyl)propionic acid (thio-ATPA), a 3-isothiazolol analogue of (RS)-2-amino-3-(5-tert-butyl-3-hydroxy-4-isoxazolyl)propionic acid (ATPA), has previously been shown to be a relatively weak AMPA receptor agonist at native (S)-glutamic acid ((S)-Glu) receptors (EC(50)=14 microM), comparable in potency with ATPA (EC(50)=34 microM). Recent findings, that (S)-ATPA is a potent (EC(50)=0.48 microM) and selective agonist at homomerically expressed ionotropic GluR5, prompted us to resolve thio-ATPA using chiral chromatography and pharmacologically characterize the two enantiomers at native as well as cloned ionotropic glutamate receptors. The enantiomers, (S)- and (R)-thio-ATPA, were obtained in high enantiomeric excess, and their absolute stereochemistry established by an X-ray crystallographic analysis. Electrophysiologically, the two enantiomers were evaluated in the rat cortical wedge preparation, and the S-enantiomer was found to be an AMPA receptor agonist (EC(50)=8.7 microM) twice as potent as the racemate, whereas the R-enantiomer was devoid of activity. In accordance with this, (S)-thio-ATPA proved to be an agonist at homomerically expressed recombinant AMPA receptors (GluR1o, GluR3o, and GluR4o) with EC(50) values of 5, 32 and 20 microM, respectively, producing maximal steady state currents of 78--168% of those maximally evoked by kainic acid, and 120-1600% of those maximally evoked by (S)-ATPA. At homomerically expressed GluR5, (S)-thio-ATPA was found to be a potent agonist (EC(50)=0.10 microM), thus being approximately five times more potent than (S)-ATPA. (R)-Thio-ATPA induced saturating currents with an estimated EC(50) value of 10 microM, most likely due to a contamination with (S)-thio-ATPA. At heteromerically expressed GluR6+KA2 receptors, (S)-thio-ATPA showed relatively weak agonistic properties (EC(50)=4.9 microM). Thus, (S)-thio-ATPA has been shown to be a very potent agonist at GluR5, and may be a valuable

  15. Modeling, simulation, and high-autonomy control of a Martian oxygen production plant

    Science.gov (United States)

    Schooley, L. C.; Cellier, F. E.; Wang, F.-Y.; Zeigler, B. P.

    1992-01-01

    Progress on a project for the development of a high-autonomy intelligent command and control architecture for process plants used to produce oxygen from local planetary resources is reported. A distributed command and control architecture is being developed and implemented so that an oxygen production plant, or other equipment, can be reliably commanded and controlled over an extended time period in a high-autonomy mode with high-level task-oriented teleoperation from one or several remote locations. During the reporting period, progress was made at all levels of the architecture. At the remote site, several remote observers can now participate in monitoring the plant. At the local site, a command and control center was introduced for increased flexibility, reliability, and robustness. The local control architecture was enhanced to control multiple tubes in parallel, and was refined for increased robustness. The simulation model was enhanced to full dynamics descriptions.

  16. A fuzzy-logic-based controller for methane production in anaerobic fixed-film reactors.

    Science.gov (United States)

    Robles, A; Latrille, E; Ruano, M V; Steyer, J P

    2017-01-01

    The main objective of this work was to develop a controller for biogas production in continuous anaerobic fixed-bed reactors, which used effluent total volatile fatty acids (VFA) concentration as control input in order to prevent process acidification at closed loop. To this aim, a fuzzy-logic-based control system was developed, tuned and validated in an anaerobic fixed-bed reactor at pilot scale that treated industrial winery wastewater. The proposed controller varied the flow rate of wastewater entering the system as a function of the gaseous outflow rate of methane and VFA concentration. Simulation results show that the proposed controller is capable to achieve great process stability even when operating at high VFA concentrations. Pilot results showed the potential of this control approach to maintain the process working properly under similar conditions to the ones expected at full-scale plants.

  17. Exploring the Potential for Increased Production from the Wave Energy Converter Lifesaver by Reactive Control

    Directory of Open Access Journals (Sweden)

    Marta Molinas

    2013-07-01

    Full Text Available Fred Olsen is currently testing their latest wave energy converter (WEC, Lifesaver, outside of Falmouth Bay in England, preparing it for commercial operation at the Wavehub test site. Previous studies, mostly focusing on hydrodynamics and peak to average power reduction, have shown that this device has potential for increased power extraction using reactive control. This article extends those analyses, adding a detailed model of the all-electric power take-off (PTO system, consisting of a permanent magnet synchronous generator, inverter and DC-link. Time domain simulations are performed to evaluate the PTO capabilities of the modeled WEC. However, when tuned towards reactive control, the generator losses become large, giving a very low overall system efficiency. Optimal control with respect to electrical output power is found to occur with low added mass, and when compared to pure passive loading, a 1% increase in annual energy production is estimated. The main factor reducing the effect of reactive control is found to be the minimum load-force constraint of the device. These results suggest that the Lifesaver has limited potential for increased production by reactive control. This analysis is nevertheless valuable, as it demonstrates how a wave-to-wire model can be used for investigation of PTO potential, annual energy production estimations and evaluations of different control techniques for a given WEC device.

  18. Implementation of the Hazard Analysis Critical Control Point (HACCP system to UF white cheese production line

    Directory of Open Access Journals (Sweden)

    Mahmoud El-Hofi

    2010-09-01

    Full Text Available Background. HACCP, or the Hazard Analysis and Critical Control Point System has been recognised as an effective and rational means of assuring food safety from primary production through to final consumption, using a “farm to table” methodology. The application of this preventive oriented approach would give the food producer better control over operation, better manufacturing practices and greater efficiencies, including reduced wastes. Material and methods. The steps taken to put HACCP in place are described and the process was monitored to assess its impact. Assessment of the hygiene quality of the UF white cheese products line before and after HACCP showed an improvement in quality and an overall improvement in the conditions at the company. Results. HACCP was introduced for the in UF White Cheese line at Misr Milk and Food, Mansoura, Egypt, for safe and good quality foods products. All necessary quality control procedures were verified for completeness and to determine if they are being implemented to required standards. A hazard analysis was conducted to identify hazards that may occur in the product cycle, Critical Control Points (CCPs were determined to control the identified hazards. CCP signs were then posted on the factory floor. Critical limits were established at each CCP, corrective actions to be taken when monitoring indicates deviation or loss of control were established. Verification procedures were established to confirm that the HACCP system is working effectively. Documentation concerning all procedures and records was established and integrating HACCP with ISO 9000 under one management system was applied. Conclusions. The HACCP system in this study for UF White Cheese line manufacture is developed step-by-step based on the twelve steps mentioned in the literature review. The prerequisite program was provided to deal with some hazards before the production to simplify the HACCP plan.

  19. A Control System for Tobacco Shred Production Line Based on Industrial Ethernet

    Science.gov (United States)

    Zhang, Li; Zheng, Guang; Zhang, Xinfeng; Liu, Lei; Xi, Lei

    The Industrial Ethernet based on IP realizes interconnection of industrial network and information network, and it is the most potential technology in the new industrial net products. In this paper, the defects of the original control system for tobacco shred production line are analyzed, and the new design plan of control system based on EtherNet/IP is presented. The control net adopts redundant 1000M fiber optic ring network that consists of six managed Industrial Ethernet Switches, and they are distributed to the central control room, leaf processing line, shred processing line, mixed stem shred processing line, online mositure regain processing line and cut tobacco dryer control cabinet. The switch in the central control room works in the pattern of redundancy management, which can switch the link in the event of the failure in link of ring net, the recovery time of link line is less than 500ms, and each main PLC of control section has dual Network Adapters. The plan has been applied for reform of 5000kg/h Tobacco Primary Processing Line in Nanyang Cigarette Factory of China Tobacco Henan Industrial Corporation, and the configurable software and Industry Ethernet network which has been used promots the capability of automatic control system fundamentally, showing much better transmission efficiency and reliability, realizing the goal of high cost performance and making equipment's ability of handling grow fast.

  20. The use of model predictive control for asset production optimization: application to a thin-rim oil field case

    NARCIS (Netherlands)

    Linden, R.D. van der; Leemhuis, A.P.

    2010-01-01

    Increasingly the upstream oil & gas industry is using active flow control (e.g. feedback loops) or passive flow control (e.g. passive ICD) technologies to optimize asset production. They are used, for example, to commingle production, stabilize production in case of water or gas breakthrough, and to

  1. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control

    Science.gov (United States)

    Perkin, Lindsey C.; Adrianos, Sherry L.; Oppert, Brenda

    2016-01-01

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi) may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA) in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs. PMID:27657138

  2. Recent progress concerning the production of controlled highly oriented electrospun nanofibrous arrays

    Science.gov (United States)

    Manea, L. R.; Hristian, L.; Leon, A. L.; Popa, A.

    2016-08-01

    Among the foreground domains of all the research-development programs at national and international level, a special place is occupied by that concerning the nanosciences, nanotechnologies, new materials and technologies. Electrospinning found a well-deserved place in this space, offering the preparation of nanomaterials with distinctive properties and applications in medicine, environment, photonic sensors, filters, etc. These multiple applications are generated by the fact that the electrospinning technology makes available the production of nanofibers with controllable characteristics (length, porosity, density, and mechanical characteristics), complexity and architecture. The apparition of 3D printing technology favors the production of complex nanofibrous structures, controlled assembly, self-assembly of electrospun nanofibers for the production of scaffolds used in various medical applications. The architecture of fibrous deposits has a special influence on the subsequent development of the cells of the reconstructed organism. The present work proposes to study of recent progress concerning the production of controlled highly oriented electrospun nanofibrous arrays and progress in research on the production of complex 2D and 3D structures.

  3. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control.

    Science.gov (United States)

    Perkin, Lindsey C; Adrianos, Sherry L; Oppert, Brenda

    2016-09-19

    Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi) may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA) in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  4. Gene Disruption Technologies Have the Potential to Transform Stored Product Insect Pest Control

    Directory of Open Access Journals (Sweden)

    Lindsey C. Perkin

    2016-09-01

    Full Text Available Stored product insects feed on grains and processed commodities manufactured from grain post-harvest, reducing the nutritional value and contaminating food. Currently, the main defense against stored product insect pests is the pesticide fumigant phosphine. Phosphine is highly toxic to all animals, but is the most effective and economical control method, and thus is used extensively worldwide. However, many insect populations have become resistant to phosphine, in some cases to very high levels. New, environmentally benign and more effective control strategies are needed for stored product pests. RNA interference (RNAi may overcome pesticide resistance by targeting the expression of genes that contribute to resistance in insects. Most data on RNAi in stored product insects is from the coleopteran genetic model, Tribolium castaneum, since it has a strong RNAi response via injection of double stranded RNA (dsRNA in any life stage. Additionally, Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR technology has been suggested as a potential resource for new pest control strategies. In this review we discuss background information on both gene disruption technologies and summarize the advances made in terms of molecular pest management in stored product insects, mainly T. castaneum, as well as complications and future needs.

  5. An efficient on-board metal-free nanocatalyst for controlled room temperature hydrogen production.

    Science.gov (United States)

    Santra, Saswati; Das, Debanjan; Das, Nirmalya Sankar; Nanda, Karuna Kar

    2017-04-01

    Positively charged functionalized carbon nanodots (CNDs) with a variety of different effective surface areas (ESAs) are synthesized via a cheap and time effective microwave method and applied for the generation of hydrogen via hydrolysis of sodium borohydride. To the best of our knowledge, this is the first report of metal-free controlled hydrogen generation. Our observation is that a positively charged functional group is essential for the hydrolysis for hydrogen production, but the overall activity is found to be enhanced with the ESA. A maximum value of 1066 ml g(-1) min(-1) as the turnover frequency is obtained which is moderate in comparison to other catalysts. However, the optimum activation energy is found to be 22.01 kJ mol(-1) which is comparable to well-known high cost materials like Pt and Ru. All of the samples showed good reusability and 100% conversion even after the 10th cycle. The effect of H(+) and OH(-) is also studied to control the on-board and on-demand hydrogen production ("on-off switching"). It is observed that H2 production decreases inversely with NaOH concentration and ceases completely when 10(-1) M NaOH is added. With the addition of HCl, H2 production can be initiated again, which confirms the on/off control over production.

  6. Geologically controlling factors on coal bed methane (CBM) productivity in Liulin

    Institute of Scientific and Technical Information of China (English)

    GAO Li-jun; TANG Da-zhen; XU Hao; MENG Shang-zhi; ZHANG Wen-zhong; MENG Yan-jun; WANG Jun-jian

    2012-01-01

    It is of great significance to forecast high yield of CBM wells and analyze dynamic production by having an overall study on the characteristics of the produced CBM and determining the main factors influencing the productivity of CBM.With the test report and the related geological parameters of a single well,methods of combining the productivity data and typical production curves were used to analyze different geological factors and how to influence the capacity of a single layer.Then,the paper proposed a new understanding about capacity characteristics of the study area and geological control factors:First,the Shanxi formation production capacity characteristics was divided into two-stages,showing signs of gas and gas breakthrough for 100 days.Second,two parameters,which include potential of gas production and gas production capacity,were better than the single parameter,such as gas content,coal thickness,and penetration to analyze affecting factors of single well production.Finally,comprehensive analysis concluded that the ratio of critical desorption pressure to reservoir pressure has greater influence on the production of vertical CBM wells.Besides,the potential of gas production capacity has greater impact at stage of showing gas signs; the coal reservoir pressure and gas production capacity have greater impact at stage of gas breakthrough for 100 days.Thus,to seek the coal bed methane with high ratio of critical desorption pressure to reservoir pressure and high yield of gas will be important guarantee to the success of the coal bed methane exploration and development.

  7. Towards an integration of process planning and production planning and control for flexible manufacturing systems

    NARCIS (Netherlands)

    Gaalman, GJC; Slomp, J; Suresh, NC

    1999-01-01

    This introduction article attempts to present some major issues relating to the integration of process planning and production planning and control (PPC) for flexible manufacturing systems (FMSs). It shows that the performance of an FMS can be significantly improved and FMS capabilities more effecti

  8. Changes in production control required for untended operation of a flexible manufacturing cell

    NARCIS (Netherlands)

    Slomp, Jannes; Stecke, Kathryn E.

    2012-01-01

    This article examines and improves the production control system of a firm that wants to operate its flexible manufacturing cell (FMC) in an untended third shift. The FMC consists of a machining centre, a pallet storage, a rail-guided transport vehicle for pallets and a clamping/unclamping station.

  9. Inventory control for a perishable product with non-stationary demand

    NARCIS (Netherlands)

    Pauls-Worm, K.G.J.

    2016-01-01

    Globally, around one-third of the edible parts of perishable food products is wasted every year. Adequate logistics management of the food supply chain is of importance. Inventory control of processed fresh food with a best-before or use-by date deals with the questions how much to order and how oft

  10. Towards an integration of process planning and production planning and control for flexible manufacturing systems

    NARCIS (Netherlands)

    Gaalman, GJC; Slomp, J; Suresh, NC

    This introduction article attempts to present some major issues relating to the integration of process planning and production planning and control (PPC) for flexible manufacturing systems (FMSs). It shows that the performance of an FMS can be significantly improved and FMS capabilities more

  11. Decoding the acts of language production for controlling brain computer interfaces

    NARCIS (Netherlands)

    Bleichner, M.G.

    2014-01-01

    Implantable brain computer interfaces (BCIs) promise to re-establish communication for severely paralyzed people. This thesis argues that decoding the acts of language production is a promising strategy for BCI control. Using high-field functional magnetic resonance imaging (fMRI) and high-density

  12. Acetic Acid Production by an Electrodialysis Fermentation Method with a Computerized Control System.

    Science.gov (United States)

    Nomura, Yoshiyuki; Iwahara, Masayoshi; Hongo, Motoyoshi

    1988-01-01

    In acetic acid fermentation by Acetobacter aceti, the acetic acid produced inhibits the production of acetic acid by this microorganism. To alleviate this inhibitory effect, we developed an electrodialysis fermentation method such that acetic acid is continuously removed from the broth. The fermentation unit has a computerized system for the control of the pH and the concentration of ethanol in the fermentation broth. The electrodialysis fermentation system resulted in improved cell growth and higher productivity over an extended period; the productivity exceeded that from non-pH-controlled fermentation. During electrodialysis fermentation in our system, 97.6 g of acetic acid was produced from 86.0 g of ethanol; the amount of acetic acid was about 2.4 times greater than that produced by non-pH-controlled fermentation (40.1 g of acetic acid produced from 33.8 g of ethanol). Maximum productivity of electrodialysis fermentation in our system was 2.13 g/h, a rate which was 1.35 times higher than that of non-pH-controlled fermentation (1.58 g/h).

  13. Changes in production control required for untended operation of a flexible manufacturing cell

    NARCIS (Netherlands)

    Slomp, Jannes; Stecke, Kathryn E.

    2012-01-01

    This article examines and improves the production control system of a firm that wants to operate its flexible manufacturing cell (FMC) in an untended third shift. The FMC consists of a machining centre, a pallet storage, a rail-guided transport vehicle for pallets and a clamping/unclamping station.

  14. Efficacy of pyriproxyfen for control of stored-product psocids (Psocoptera) on concrete surfaces

    Science.gov (United States)

    The insect growth regulator pyriproxyfen was evaluated as a surface treatment for control of three stored-product psocid pests, Liposcelis bostrychophila Badonnel, L. decolor (Pearman), and L. paeta Pearman (Psocoptera: Liposcelididae). Nymphs were exposed for 35 d on a concrete surface treated with...

  15. Potential Use of Chlorine Dioxide to Control Diseases in Ornamental Plant Production Systems

    Science.gov (United States)

    Research is being done to evaluate uses of chlorine dioxide in ornamental plant production systems. Chlorine dioxide has been shown to control spread of Fusarium oxysporum during the hot water treatment of daffodils and should provide replacement of formaldehyde which was used in the past. By dipp...

  16. Specification and Estimation of Production Functions Involving Damage Control Inputs: A Two-Stage, Semiparametric Approach

    NARCIS (Netherlands)

    Kuosmanen, T.K.; Pemsl, D.; Wesseler, J.H.H.

    2006-01-01

    Productivity assessment of damage control inputs (such as pesticides) is complicated because their effect depends on the exposure to damage agents (such as pests). We discuss some open specification and estimation issues. The contribution is threefold. First, we elaborate the separability conditions

  17. Heterologous production of pediocin for the control of Listeria monocytogenes in dairy foods

    Science.gov (United States)

    Pediocin is an antimicrobial peptide naturally produced by Pediococci with the potential to serve as a food-grade preservative for controlling Listeria contamination. The use of Pediococci in dairy products is limited due to their inability to ferment lactose, thus lactic acid bacteria (LAB) have b...

  18. Effect of Art Production on Negative Mood: A Randomized, Controlled Trial

    Science.gov (United States)

    Bell, Chloe E.; Robbins, Steven J.

    2007-01-01

    Art therapists have long held that art production causes reductions in stress and elevations in mood (Rubin, 1999). The authors examined this claim in a randomized, controlled trial. Fifty adults between the ages of 18 and 30 were randomly assigned to either create an art work or to view and sort a series of art prints. Three measures of overall…

  19. Applications and consequences of bacteriocins to control Campylobacter spp. in poultry production

    Science.gov (United States)

    The unacceptably high frequency of Campylobacter jejuni transmission from poultry to humans encourages scientists to consider and create alternative intervention strategies to control the pathogen in poultry production. Extremely high numbers of Campylobacter (often >108 cfu/g of poultry intestinal...

  20. Towards a decision support system for control of multiple food safety hazards in raw milk production

    NARCIS (Netherlands)

    Spiegel, van der M.; Sterrenburg, P.; Haasnoot, W.; Fels-Klerx, van der H.J.

    2013-01-01

    Decision support systems (DSS) for controlling multiple food safety hazards in raw milk production have not yet been developed, but the underlying components are fragmentarily available. This article presents the state-of-the-art of essential DSS elements for judging food safety compliance of raw mi