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1994
Pereira, Z, Kovács I, Moniz A.  1994.  {Quality and work organization with advanced automation in Portugal}, Jul. , Number 7567: University Library of Munich, Germany Abstract

In this paper it is analysed the relationships between work organisation and quality systems in firms that uses some forms of advanced automation. Are characterised the existing quality control structures in the Portuguese industry, and the main factors that hidden or fosters the development of sociotechnical methods of quality control organisation strategies. Are analysed some industrial cases that explains more clearly the critical issues of the implementation of quality systems and work organisation systems. A few recommendations are given about the possibilities for the development of new forms of work organisation and the quality systems associated to automated manufacturing systems.

Moniz, A.  1994.  {The automobile sector and the organisation of the industrial space: the case of Setúbal Region (Portugal)}, Jul. , Number 7503: University Library of Munich, Germany Abstract

This paper is based on a study about the Setúbal region, included in the internacional project “The Future of Industry in Europe” for the programme FAST-MONITOR of the European Community (1992-94). There were some information on the project VW/Ford for this region and those that are connected with research networks on industrial sectors (specially, on the automobile industry), and the network on the spatial and regional factors of regional development. Those studies allowed the scenario development on evolution trends of European industry and, specifically, on the automobile sector, and on the Setúbal region that was studied by the Portuguese team.

Kovács, I, Moniz A.  1994.  {Trends for the development of anthropocentric production systems in small less industrialised countries: The case of Portugal}, Jul. , Number 6551: University Library of Munich, Germany Abstract

This paper analyses the problems and trends of the introduction of anthropocentric production systems (APS) in small less industrialized member states of the European Union, specifically the case of Portugal, based on the report for the FAST-Anthropocentric Technology Assessment Project (Monitor Programme) on “Prospects and conditions for APS in Europe by the 21st century”. Research teams from all countries of the European Community, as well as researchers from USA, Japan and Australia were participating in this project. The aim of this paper is to characterize APS and to present some special considerations related to the socioeconomic factors affecting the prospects and conditions for APS in Portugal. APS is defined as a system based on the utilization of skilled human resources and flexible technology adapted to the needs of flexible and participative organization. Among socioeconomic factors, some critical aspects for the development of APS will be focused, namely technological infrastructure, management strategies, perceived impact of introduction of automated systems on the division of labor and organizational structure, educational and vocational training and social actors strategies towards industrial automation. This analysis is based on a sample of industrial firms, built up for qualitative analysis, and on case studies analysis that can be reference examples for further development of APS, and not just for economic policy purposes alone. We have also analyzed the type of existing industrial relations, the union and employer strategies and some aspects of public policies towards the introduction of new technologies in the order to understand the extent to which there exist obstacles to and favorable conditions for the diffusion of anthropocentric systems. Finally some recommendations are presented to stress the trends for the implementation and development of anthropocentric production systems in Portugal.

Moreno, C, Macedo AL, Moura I, Legall J, Moura JJ.  1994.  Redox properties of Desulfovibrio gigas [Fe3S4] and [Fe4S4] ferredoxins and heterometal cubane-type clusters formed within the [Fe3S4] core. Square wave voltammetric studies, Feb 15. J Inorg Biochem. 53:219-34., Number 3 AbstractWebsite

The same polypeptide chain (58 amino acids, 6 cysteines) is used to build up two ferredoxins in Desulfovibrio gigas a sulfate reducing organism. Ferredoxin II (FdII) contains a single [Fe3S4] core and ferredoxin I (FdI) mainly a [Fe4S4] core. The [Fe3S4] core can readily be interconverted into a [Fe4S4] complex (J.J.G. Moura, I. Moura, T.A. Kent, J.D. Lipscomb, B.H. Huynh, J. LeGall, A.V. Xavier, and E. Munck, J. Biol. Chem. 257, 6259 (1982)). This interconversion process suggested that the [Fe3S4] core could be used as a synthetic precursor for the formation of heterometal clusters. Co, Zn, Cd, and Ni derivatives were produced (I. Moura, J.J.G. Moura, E. Munck, V. Papaephthymiou, and J. LeGall, J. Am. Chem. Soc. 108, 349 (1986), K. Sureurs, E. Munck, I. Moura, J.J.G. Moura, and J. LeGall, J. Am. Chem. Soc. 109, 3805 (1986), and A.L. Macedo, I. Moura, J.J.G. Moura, K. Surerus, and E. Munck, unpublished results). The redox properties of a series of heterometal clusters (MFe3S4] are assessed using direct electrochemistry (square wave voltammetry--SWV) promoted by Mg(II) at a glassy carbon electrode (derivatives: Cd (-495 mV), Fe (-420 mV), Ni (-360 mV), and Co (-245 mV) vs normal hydrogen electrode (NHE)). In parallel, the electrochemical behavior (cyclic voltammetry--CV, differential pulse voltammetry--DPV and SWV) of FdI and FdII were investigated as well as the cluster interconversion process. In addition to the +1/0 (3Fe cluster) and +2/+1 (4Fe cluster) redox transitions, a very negative redox step, at -690 mV, was detected for the 3Fe core, reminiscent of a postulated further 2e- reduction step, as proposed for D. africanus ferredoxin III by F.A. Armstrong, S.J. George, R. Cammack, E.C. Hatchikian, and A.J. Thomson, Biochem. J. 264, 265 (1989). The electrochemical redox potential values are compared with those determined by independent methods (namely by electron paramagnetic resonance (EPR) and visible spectroscopy).

De Francesco, R, Edmondson DE, Moura I, Moura JJ, Legall J.  1994.  Kinetic studies on the electron-transfer reaction between cytochrome c3 and flavodoxin from Desulfovibrio vulgaris strain Hildenborough, Aug 30. Biochemistry. 33:10386-92., Number 34 AbstractWebsite

The kinetic properties of the electron-transfer process between reduced Desulfovibrio vulgaris cytochrome c3 and D. vulgaris flavodoxin have been studied by anaerobic stopped-flow techniques. Anaerobic titrations of reduced cytochrome c3 with oxidized flavodoxin show a stoichiometry of 4 mol of flavodoxin required to oxidize the tetraheme cytochrome. Flavodoxin neutral semiquinone and oxidized cytochrome c3 are the only observable products of the reaction. At pH 7.5, the four-electron-transfer reaction is biphasic. Both the rapid and the slow phases exhibit limiting rates as the flavodoxin concentration is increased with respective rates of 73.4 and 18.5 s-1 and respective Kd values of 65.9 +/- 9.4 microM and 54.5 +/- 13 microM. A biphasic electron-transfer rate is observed when the ionic strength is increased to 100 mM KCl; however, the observed rate is no longer saturable, and relative second-order rate constants of 5.3 x 10(5) and 8.5 x 10(4) M-1 s-1 are calculated. The magnitude of the rapid phase of electron transfer diminishes with the level of heme reduction when varying reduced levels of the cytochrome are mixed with oxidized flavodoxin. No rapid phase is observed when 0.66e(-)-reduced cytochrome c3 reacts with an approximately 25-fold molar excess of flavodoxin. At pH 6.0, the electron-transfer reaction is monophasic with a limiting rate of 42 +/- 1.4 s-1 and a Kd value of approximately 8 microM. Increasing the ionic strength of the pH 6.0 solution to 100 microM KCl results in a biphasic reaction with relative second-order rate constants of 5.3 x 10(5) and 1.1 x 10(4) M-1 s-1. Azotobacter vinelandii flavodoxin reacts with reduced D. vulgaris cytochrome c3 in a slow, monophasic manner with limiting rate of electron transfer of 1.2 +/- 0.06 s-1 and a Kd value of 80.9 +/- 10.7 microM. These results are discussed in terms of two equilibrium conformational states for the cytochrome which are dependent on the pH of the medium and the level of heme reduction [Catarino et al. (1991) Eur. J. Biochem. 207, 1107-1113].

De Francesco, R, Edmondson DE, Moura I, Moura JJG, Legall J.  1994.  Kinetic-Studies On The Electron-Transfer Reaction Between Cytochrome-C(3) And Flavodoxin From Desulfovibrio-vulgaris Strain Hildenborough, Aug 30. Biochemistry. 33:10386-10392., Number 34 AbstractWebsite

The kinetic properties of the electron-transfer process between reduced Desulfovibrio vulgaris cytochrome c(3) and D. vulgaris flavodoxin have been studied by anaerobic stopped-flow techniques. Anaerobic titrations of reduced cytochrome c(3) with oxidized flavodoxin show a stoichiometry of 4 mol of flavodoxin required to oxidize the tetraheme cytochrome. Flavodoxin neutral semiquinone and oxidized cytochrome c(3) are the only observable products of the reaction. At pH 7.5, the four-electron-transfer reaction is biphasic. Both the rapid and the slow phases exhibit limiting rates as the flavodoxin concentration is increased with respective rates of 73.4 and 18.5 s(-1) and respective K-d values of 65.9 +/- 9.4 mu M and 54.5 +/- 13 CIM. A biphasic electron-transfer rate is observed when the ionic strength is increased to 100 mM KCl; however, the observed rate is no longer saturable, and relative second-order rate constants of 5.3 X 10(5) and 8.5 x 10(4) M(-1) s(-1) are calculated. The magnitude of the rapid phase of electron transfer diminishes with the level of heme reduction when varying reduced levels of the cytochrome are mixed with oxidized flavodoxin. No rapid phase is observed when 0.66e(-)-reduced cytochrome c(3) reacts with an similar to 25-fold molar excess of flavodoxin. At pH 6.0, the electron-transfer reaction is monophasic with a limiting rate of 42 +/- 1.4 s(-1) and a Kd value of similar to 8 mu M. Increasing the ionic strength of the pH 6.0 solution to 100 mu M KCl results in a biphasic reaction with relative second-order rate constants of 5.3 x 10(5) and 1.1 x 10(4) M(-1) s(-1) Azotobacter vinelandii flavodoxin reacts with reduced D. vulgaris cytochrome cs in a slow, monophasic manner with limiting rate of electron transfer of 1.2 +/- 0.06 s(-1) and a K-d value of 80.9 +/- 10.7 mu M. These results are discussed in terms of two equilibrium conformational states for the cytochrome which are dependent on the pH of the medium and the level of heme reduction [Catarino et al. (1991) Eur. J. Biochem. 207, 1107-1113].

Tavares, P, Ravi N, Moura JJ, Legall J, Huang YH, Crouse BR, Johnson MK, Huynh BH, Moura I.  1994.  Spectroscopic properties of desulfoferrodoxin from Desulfovibrio desulfuricans (ATCC 27774), Apr 8. J Biol Chem. 269:10504-10., Number 14 AbstractWebsite

Desulfoferrodoxin, a non-heme iron protein, was purified previously from extracts of Desulfovibrio desulfuricans (ATCC 27774) (Moura, I., Tavares, P., Moura, J. J. G., Ravi, N., Huynh, B. H., Liu, M.-Y., and LeGall, J. (1990) J. Biol. Chem. 265, 21596-21602). The as-isolated protein displays a pink color (pink form) and contains two mononuclear iron sites in different oxidation states: a ferric site (center I) with a distorted tetrahedral sulfur coordination similar to that found in desulforedoxin from Desulfovibrio gigas and a ferrous site (center II) octahedrally coordinated with predominantly nitrogen/oxygen-containing ligands. A new form of desulfoferrodoxin which displays a gray color (gray form) has now been purified. Optical, electron paramagnetic resonance (EPR), and Mossbauer data of the gray desulfoferrodoxin indicate that both iron centers are in the high-spin ferric states. In addition to the EPR signals originating from center I at g = 7.7, 5.7, 4.1, and 1.8, the gray form of desulfoferrodoxin exhibits a signal at g = 4.3 and a shoulder at g = 9.6, indicating a high-spin ferric state with E/D approximately 1/3 for the oxidized center II. Redox titrations of the gray form of the protein monitored by optical spectroscopy indicate midpoint potentials of +4 +/- 10 and +240 +/- 10 mV for centers I and II, respectively. Mossbauer spectra of the gray form of the protein are consistent with the EPR finding that both centers are high-spin ferric and can be analyzed in terms of the EPR-determined spin Hamiltonian parameters. The Mossbauer parameters for both the ferric and ferrous forms of center II are indicative of a mononuclear high spin iron site with octahedral coordination and predominantly nitrogen/oxygen-containing ligands. Resonance Raman studies confirm the structural similarity of center I and the distorted tetrahedral FeS4 center in desulforedoxin and provide evidence for one or two cysteinyl-S ligands for center II. On the basis of the resonance Raman results, the 635 nm absorption band that is responsible for the gray color of the oxidized protein is assigned to a cysteinyl-S-->Fe(III) charge transfer transition localized on center II. The novel properties and possible function of center II are discussed in relation to those of mononuclear iron centers in other enzymes.

Parola, AJ, Pina F, Maestri M, Armaroli N, Balzani V.  1994.  SUPRAMOLECULAR PHOTOCHEMISTRY AND PHOTOPHYSICS - 9-CYANOANTHRACENE IMPRISONED IN A HEMICARCERAND, 1994. New Journal of Chemistry. 18:659-661. AbstractWebsite

The absorption and excited state properties of 9-cyanoanthracene are strongly modified upon inclusion into an octaimine hemicarcerand; the walls of the host do not transfer excitation to the guest and quench its fluorescent excited state.

Lampreia, J, Pereira AS, Moura JJG.  1994.  ADENYLYLSULFATE REDUCTASES FROM SULFATE-REDUCING BACTERIA. {243}:{241-260}., 525 B STREET, SUITE 1900, SAN DIEGO, CA 92101-4495: ACADEMIC PRESS INC Abstract
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Moura, JJ, Barata BA.  1994.  Aldehyde oxidoreductases and other molybdenum containing enzymes. Methods Enzymol. 243:24-42. AbstractWebsite
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Saraiva, LM, Besson S, Fauque G, Moura I.  1994.  Characterization of the Dihemic Cytochrome C549 from the Marine Denitrifying Bacterium Pseudomonas nautica 617. Biochemical and Biophysical Research Communications. 199:1289-1296., Number 3 AbstractWebsite
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Lima, JC, DANESH P, FIGUEIREDO P, PINA FS, MACANITA A.  1994.  EXCITED-STATES OF ANTHOCYANINS - THE CHALCONE ISOMERS OF MALVIDIN 3,5-DIGLUCOSIDE. Photochemistry and Photobiology. 59:412-418., Number 4 Abstract
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Moura, JJ, Macedo AL, Palma PN.  1994.  Ferredoxins. Methods Enzymol. 243:165-88. AbstractWebsite
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Ferreira, GC, Franco R, Lloyd SG, Pereira AS, Moura I, Moura JJG, Huynh BH.  1994.  MAMMALIAN FERROCHELATASE, A NEW ADDITION TO THE METALLOENZYME FAMILY. Journal Of Biological Chemistry. {269}:{7062-7065}., Number {10}, 9650 ROCKVILLE PIKE, BETHESDA, MD 20814: AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC Abstract

A [2Fe-2S] cluster has been detected in mammalian ferrochelatase, the terminal enzyme of the heme biosynthetic pathway. Natural ferrochelatase, purified from mouse livers, and recombinant ferrochelatase, purified from an overproducing strain of Escherichia coli, were investigated by electron paramagnetic resonance (EPR) and Mossbauer spectroscopy. In their reduced forms, both the natural and recombinant ferrochelatases exhibited an identical EPR signal with g values (g = 2.00, 1.93, and 1.90) and relaxation properties typical of [2Fe-2S](+) cluster. Mossbauer spectra of the recombinant ferrochelatase, purified from a strain of E. coli cells transformed with a plasmid encoding murine liver ferrochelatase and grown in Fe-57-enriched medium, demonstrated unambiguously that the cluster is a [2Fe-2S] cluster. No change in the cluster oxidation state was observed during catalysis, The putative protein binding site for the Fe-S cluster in mammalian ferrochelatases is absent from the sequences of the bacterial and yeast enzymes, suggesting a possible role of the [2Fe-2S] center in regulation of mammalian ferrochelatases.

Thoenes, U, Flores OL, Neves A, Devreese B, Van Beeumen JJ, Huber R, Romao MJ, Legall J, Moura JJG, Rodriguespousada C.  1994.  MOLECULAR-CLONING AND SEQUENCE-ANALYSIS OF THE GENE OF THE MOLYBDENUM-CONTAINING ALDEHYDE OXIDOREDUCTASE OF DESULFOVIBRIO-GIGAS - THE DEDUCED AMINO-ACID-SEQUENCE SHOWS SIMILARITY TO XANTHINE DEHYDROGENASE. European Journal of Biochemistry. 220:901-910., Number 3 AbstractWebsite
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FIGUEIREDO, P, Lima JC, Santos H, WIGAND MC, Brouillard R, Macanita AL, Pina F.  1994.  PHOTOCHROMISM OF THE SYNTHETIC 4',7-DIHYDROXYFLAVYLIUM CHLORIDE. Journal of the American Chemical Society. 116:1249-1254., Number 4 Abstract
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Melo, MJ, Macanita AL, Melo E, Wamhoff H, Pina F.  1994.  PHOTOPHYSICAL PROPERTIES AND PHOTODEGRADATION MECHANISM OF 2-(2'-FURANYL)-1H-BENZIMIDAZOLE (FUBERIDAZOLE). Journal of Photochemistry and Photobiology a-Chemistry. 83:237-244., Number 3 AbstractWebsite
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Saraiva, LM, Fauque G, Besson S, Moura I.  1994.  Physico-chemical and Spectroscopic Properties of the Monohemic Cytochrome C552 from Pseudomonas nautica 617. European Journal of Biochemistry. 224:1011-1017., Number 3: Blackwell Science Ltd AbstractWebsite

A c-type monohemic ferricytochrome c552 (11 kDa) was isolated from the soluble extract of a marine denitrifier, Pseudomonas nautica strain 617, grown under anaerobic conditions with nitrate as final electron acceptor. The NH2-terminal sequence and the amino acid composition of the cytochrome were determined. The heme iron of the cytochrome c552 has histidine-methionine as axial ligands, and a pH-dependent mid-point redox potential, equal to 250 mV at pH 7.6. The presence of methionine was demonstrated by visible, EPR and NMR spectroscopies. The assignment of most of the hemic protons was performed applying two-dimensional NOE spectroscopy (NOESY), and the aromatic region was assigned through two-dimensional correlated spectroscopy (COSY) experiments. The EPR spectrum of the oxidised form of the cytochrome c552 is typical of a low-spin ferric heme.

Saraiva, LM, Thomson AJ, Lebrun NE, Liu MY, Payne WJ, Legall J, Moura I.  1994.  Replacement of Methionine as the Axial Ligand of Achromobacter cycloclastes Cytochrome C554 at High pH Values Revealed by Absorption, EPR and MCD Spectroscopy. Biochemical and Biophysical Research Communications. 204:120-128., Number 1 AbstractWebsite
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Tavares, P, Ravi N, Moura JJG, Legall J, Huang YH, Crouse BR, Johnson MK, Huynh BH, Moura I.  1994.  SPECTROSCOPIC PROPERTIES OF DESULFOFERRODOXIN FROM DESULFOVIBRIO-DESULFURICANS (ATCC-27774). Journal Of Biological Chemistry. {269}:{10504-10510}., Number {14} Abstract

Desulfoferrodoxin, a non-heme iron protein, was purified previously from extracts of Desulfovibrio desulfuricans (ATCC 27774) (Moura, I., Tavares, P., Moura, J. J. G., Ravi, N., Huynh, B. H., Liu, M.-Y., and LeGall, J. (1990) J. Biol. Chem. 265, 21596-21602). The as-isolated protein displays a pink color (pink form) and contains two mononuclear iron sites in different oxidation states: a ferric site (center I) with a distorted tetrahedral sulfur coordination similar to that found in desulforedoxin from Desulfovibrio gigas and a ferrous site (center II) octahedrally coordinated with predominantly nitrogen/ oxygen-containing ligands. A new form of desulfoferrodoxin which displays a gray color (gray form) has now been purified. Optical, electron paramagnetic resonance (EPR), and Mossbauer data of the gray desulfoferrodoxin indicate that both iron centers are in the high-spin ferric states. In addition to the EPR signals originating from center I at g = 7.7, 5.7, 4.1, and 1.8, the gray form of desulfoferrodoxin exhibits a signal atg = 4.3 and a shoulder at g = 9.6, indicating a high-spin ferric state with E/D approximate to 1/3 for the oxidized center II. Redox titrations of the gray form of the protein monitored by optical spectroscopy indicate midpoint potentials of +4 +/- 10 and +240 +/- 10 mV for centers I and II, respectively. Mossbauer spectra of the gray form of the protein are consistent with the EPR finding that both centers are high-spin ferric and can be analyzed in terms of the EPR-determined spin Hamiltonian parameters. The Mossbauer parameters for both the ferric and ferrous forms of center II are indicative of a mononuclear high spin iron site with octahedral coordination and predominantly nitrogen/oxygen-containing ligands. Resonance Raman studies confirm the structural similarity of center I and the distorted tetrahedral FeS4 center in desulforedoxin and provide evidence for one or two cysteinyl-S ligands for center II. On the basis of the resonance Raman results, the 635 nm absorption band that is responsible for the gray color of the oxidized protein is assigned to a cysteinyl-S --> Fe(III) charge transfer transition localized on center II. The novel properties and possible function of center II are discussed in relation to those of mononuclear iron centers in other enzymes.

Moura, I, Tavares P, Ravi N.  1994.  [15] Characterization of three proteins containing multiple iron sites: Rubrerythrin, desulfoferrodoxin, and a protein containing a six-iron cluster. Methods in Enzymology. Volume 243(Harry D. Peck, Jr Jean LeGall, Ed.).:216-240.: Academic Press Abstract
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Lampreia, J, Pereira AS, Moura JJG.  1994.  [16] Adenylylsulfate reductases from sulfate-reducing bacteria. Methods in Enzymology. Volume 243(Harry D. Peck, Jr Jean LeGall, Ed.).:241-260.: Academic Press Abstract
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Moura, I, Lino AR.  1994.  [20] Low-spin sulfite reductases. Methods in Enzymology. Volume 243(Harry D. Peck, Jr Jean LeGall, Ed.).:296-303.: Academic Press Abstract
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Liu, M-C, Costa C, Moura I.  1994.  [21] Hexaheme nitrite reductase from Desulfovibrio desulfuricans (ATCC 27774). Methods in Enzymology. Volume 243(Harry D. Peck, Jr Jean LeGall, Ed.).:303-319.: Academic Press Abstract
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