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2007
Rial-Otero, R, Gaspar EM, Moura I, Capelo JL.  2007.  Chromatographic-based methods for pesticide determination in honey: An overview, Feb 15. Talanta. 71:503-514., Number 2 AbstractWebsite

Nowadays the control of pesticides in honey is an issue of primary health importance as consequence of the increasing content of these chemicals in the aforementioned matrix. This poisoning has led to the worldwide increasing loss of bees since 1995. From Europe to Canada, scientist, beekeepers and chemical companies disagree about the reasons that have led to colony losses higher than 50% in some areas. This problem has become a public health issue due to the high honey worldwide consumption. The presence of pesticides in honey has been directly related to bees' mortality by some researchers through pesticide presence in (1) pollen, (2) honeycomb walls, (3) own bees and (4) honey. In this work we describe the actual state-of-the-art for pesticides determination in honey along with a review in this subject focused on sample treatments and instrumentation. Finally, future trends are also commented. (c) 2006 Elsevier B.V. All rights reserved.

Rial-Otero, R, Carreira RJ, Cordeiro FM, Moro AJ, Fernandes L, Moura I, Capelo JL.  2007.  Sonoreactor-based technology for fast high-throughput proteolytic digestion of proteins, Feb. Journal of Proteome Research. 6:909-912., Number 2 AbstractWebsite

Fast (120 s) and high-throughput (more than six samples at once) in-gel trypsin digestion of proteins using sonoreactor technology has been achieved. Successful protein identification was done by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, MALDI-TOF-MS. Specific identification of the adenylylsulphate reductase alfa subunit from a complex protein mixture from Desulfovibrio desulfuricans ATCC 27774 was done as a proof of the methodology. The new sample treatment is of easy implementation, saves time and money, and can be adapted to online procedures and robotic platforms.

Macedo, C, Branco PS, Ferreira LM, Lobo AM, Capela JP, Fernandes E, de Lourdes Bastos M, Carvalho F.  2007.  Synthesis and cyclic voltammetry studies of 3,4-methylenedioxymethamphetamine (MDMA) human metabolites, FEB. JOURNAL OF HEALTH SCIENCE. 53:31-42., Number 1 Abstract
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Corvo, M, Pereira MMA.  2007.  Synthesis of gamma-amino acid analogues from natural alpha-amino acids by a radical pathway, FEB. AMINO ACIDS. 32:243-246., Number 2 Abstract
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Rauter, AP, Branco I, Lopes RG, Justino J, Silva FVM, Noronha JP, Cabrita EJ, Brouard I, Bermejo J.  2007.  A new lupene triterpenetriol and anticholinesterase activity of Salvia sclareoides, DEC 2007. Fitoterapia. 78:474-481., Number 7-8 Abstract

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Moniz, AB, Woll T.  2007.  Main features of the labour policy in Portugal, Dec. , Number 02/2007: Universidade Nova de Lisboa, IET-Research on Enterprise and Work Innovation, Faculty of Science and Technology Abstract

In this working paper is presented information on the Portuguese labour market developed with the support of the European project WORKS-“Work organisation and restructuring in the knowledge society”. Is still a on the process article and thus commentaries are welcome. The structure is based on the following topics: a) The employment policy (Time regimes - time use, flexibility, part-time work, work-life balance -, and the work contracts regimes – wages, contract types, diversity); b) Education and training (skilling outcomes, rules on retraining and further training, employability schemes, transferability of skills); c) Equal opportunities (relevance of equal opportunity regulation for restructuring outcomes, the role of gender and age regulation); d) Restructuring effects (policy on transfer of personnel, policy on redundancies, and participation or voice in restructuring).

Moniz, AB, Woll T.  2007.  Main features of the labour policy in Portugal, Dec. , Number hal-00287900: HAL Abstract

In this working paper is presented information on the Portuguese labour market developed with the support of the European project WORKS-“Work organisation and restructuring in the knowledge society”. Is still a on the process article and thus commentaries are welcome. The structure is based on the following topics: a) The employment policy (Time regimes - time use, flexibility, part-time work, work-life balance -, and the work contracts regimes – wages, contract types, diversity); b) Education and training (skilling outcomes, rules on retraining and further training, employability schemes, transferability of skills); c) Equal opportunities (relevance of equal opportunity regulation for restructuring outcomes, the role of gender and age regulation); d) Restructuring effects (policy on transfer of personnel, policy on redundancies, and participation or voice in restructuring).

Valenduc, G, Vendramin P, Krings B, Nierling L.  2007.  {How restructuring is changing occupations? Case study evidence from knowledge-intensive, manufacturing and service occupations}, Dec , Number 67055: ZBW - German National Library of Economics Abstract

This report is the final deliverable (D11.1) of the workpackage on occupational case studies of the WORKS project (WP11 – Qualitative research – Case studies on changes in work - Impacts on the individual and the household). In this workpackage, 30 occupational case studies were achieved in 14 countries, between June 2006 and May 2007; in total 246 in-depth individual interviews were carried out, according to common interview guidelines elaborated in May 2006, at the end of the workpackage on qualitative methods (WP6). These occupational case studies are closely related to the organisational case studies that were carried out in a selected number of business functions, during the same time span. In the WORKS project, business functions are at the core of qualitative empirical research, as they provide a relevant framework for analysis of value chain restructuring and changes in work. In order to study changes in work at the individual level, this report focuses on individual workers within occupational groups linked to key business functions. This link is justified in Chapter 2. Six occupational groups are considered in the report: designers in the clothing industry; researchers in information and communication technology; IT professionals in software services; production workers in food or clothing; logistics workers in food or clothing; front office employees in customer relationships in public services. In each occupational group, three to seven case studies were conducted an reported in different countries, covering a variety of socio-economic and institutional contexts. Each case study relies on seven to nine in-depth individual interviews, including a biographical dimension. In the first part of this report (Chapter 2), the research design and methodology are explained and justified. The key research questions are developed, as well as the concrete methodological choices and the practical organisation of the case studies. The second part of the report (Chapter

Moniz, AB, Woll T.  2007.  {Main features of the labour policy in Portugal}, Dec. , Number 02/2007: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

In this working paper is presented information on the Portuguese labour market developed with the support of the European project WORKS-“Work organisation and restructuring in the knowledge society”. Is still a on the process article and thus commentaries are welcome. The structure is based on the following topics: a) The employment policy (Time regimes - time use, flexibility, part-time work, work-life balance -, and the work contracts regimes – wages, contract types, diversity); b) Education and training (skilling outcomes, rules on retraining and further training, employability schemes, transferability of skills); c) Equal opportunities (relevance of equal opportunity regulation for restructuring outcomes, the role of gender and age regulation); d) Restructuring effects (policy on transfer of personnel, policy on redundancies, and participation or voice in restructuring).

Moniz, AB, Woll T.  2007.  {Main features of the labour policy in Portugal}, Dec. , Number hal-00287900: HAL Abstract

In this working paper is presented information on the Portuguese labour market developed with the support of the European project WORKS-“Work organisation and restructuring in the knowledge society”. Is still a on the process article and thus commentaries are welcome. The structure is based on the following topics: a) The employment policy (Time regimes - time use, flexibility, part-time work, work-life balance -, and the work contracts regimes – wages, contract types, diversity); b) Education and training (skilling outcomes, rules on retraining and further training, employability schemes, transferability of skills); c) Equal opportunities (relevance of equal opportunity regulation for restructuring outcomes, the role of gender and age regulation); d) Restructuring effects (policy on transfer of personnel, policy on redundancies, and participation or voice in restructuring).

Moniz, AB, Woll T.  2007.  {Main features of the labour policy in Portugal}, Dec. , Number hal-00287900: HAL Abstract

In this working paper is presented information on the Portuguese labour market developed with the support of the European project WORKS-“Work organisation and restructuring in the knowledge society”. Is still a on the process article and thus commentaries are welcome. The structure is based on the following topics: a) The employment policy (Time regimes - time use, flexibility, part-time work, work-life balance -, and the work contracts regimes – wages, contract types, diversity); b) Education and training (skilling outcomes, rules on retraining and further training, employability schemes, transferability of skills); c) Equal opportunities (relevance of equal opportunity regulation for restructuring outcomes, the role of gender and age regulation); d) Restructuring effects (policy on transfer of personnel, policy on redundancies, and participation or voice in restructuring).

Maia, L, Duarte RO, Ponces-Freire A, Moura JJ, Mira L.  2007.  NADH oxidase activity of rat and human liver xanthine oxidoreductase: potential role in superoxide production, Aug. J Biol Inorg Chem. 12:777-87., Number 6 AbstractWebsite

To characterise the NADH oxidase activity of both xanthine dehydrogenase (XD) and xanthine oxidase (XO) forms of rat liver xanthine oxidoreductase (XOR) and to evaluate the potential role of this mammalian enzyme as an O2*- source, kinetics and electron paramagnetic resonance (EPR) spectroscopic studies were performed. A steady-state kinetics study of XD showed that it catalyses NADH oxidation, leading to the formation of one O2*- molecule and half a H(2)O(2) molecule per NADH molecule, at rates 3 times those observed for XO (29.2 +/- 1.6 and 9.38 +/- 0.31 min(-1), respectively). EPR spectra of NADH-reduced XD and XO were qualitatively similar, but they were quantitatively quite different. While NADH efficiently reduced XD, only a great excess of NADH reduced XO. In agreement with reductive titration data, the XD specificity constant for NADH (8.73 +/- 1.36 microM(-1) min(-1)) was found to be higher than that of the XO specificity constant (1.07 +/- 0.09 microM(-1) min(-1)). It was confirmed that, for the reducing substrate xanthine, rat liver XD is also a better O2*- source than XO. These data show that the dehydrogenase form of liver XOR is, thus, intrinsically more efficient at generating O2*- than the oxidase form, independently of the reducing substrate. Most importantly, for comparative purposes, human liver XO activity towards NADH oxidation was also studied, and the kinetics parameters obtained were found to be very similar to those of the XO form of rat liver XOR, foreseeing potential applications of rat liver XOR as a model of the human liver enzyme.

Costa, VM, Silva R, Ferreira LM, Branco PS, Carvalho F, Bastos ML, Carvalho RA, Carvalho M, Remiao F.  2007.  Oxidation process of adrenaline in freshly isolated rat cardiomyocytes: Formation of adrenochrome, quinoproteins, and GSH adduct, AUG. CHEMICAL RESEARCH IN TOXICOLOGY. 20:1183-1191., Number 8 Abstract
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Ghosh, S, Gorelsky SI, George SD, Chan JM, Cabrito I, Dooley DM, Moura JJ, Moura I, Solomon EI.  2007.  Spectroscopic, computational, and kinetic studies of the mu4-sulfide-bridged tetranuclear CuZ cluster in N2O reductase: pH effect on the edge ligand and its contribution to reactivity, Apr 4. J Am Chem Soc. 129:3955-65., Number 13 AbstractWebsite

A combination of spectroscopy and density functional theory (DFT) calculations has been used to evaluate the pH effect at the CuZ site in Pseudomonas nautica (Pn) nitrous oxide reductase (N2OR) and Achromobacter cycloclastes (Ac) N2OR and its relevance to catalysis. Absorption, magnetic circular dichroism, and electron paramagnetic resonance with sulfur K-edge X-ray absorption spectra of the enzymes at high and low pH show minor changes. However, resonance Raman (rR) spectroscopy of PnN2OR at high pH shows that the 415 cm-1 Cu-S vibration (observed at low pH) shifts to higher frequency, loses intensity, and obtains a 9 cm-1 18O shift, implying significant Cu-O character, demonstrating the presence of a OH- ligand at the CuICuIV edge. From DFT calculations, protonation of either the OH- to H2O or the mu4-S2- to mu4-SH- would produce large spectral changes which are not observed. Alternatively, DFT calculations including a lysine residue at an H-bonding distance from the CuICuIV edge ligand show that the position of the OH- ligand depends on the protonation state of the lysine. This would change the coupling of the Cu-(OH) stretch with the Cu-S stretch, as observed in the rR spectrum. Thus, the observed pH effect (pKa approximately 9.2) likely reflects protonation equilibrium of the lysine residue, which would both raise E degrees and provide a proton for lowering the barrier for the N-O cleavage and for reduction of the [Cu4S(im)7OH]2+ to the fully reduced 4CuI active form for turnover.

de Macedo, CV, da Silva MS, Casimiro T, Cabrita EJ, Aguiar-Ricardo A.  2007.  Boron trifluoride catalyzed polymerisation of 2-substituted-2-oxazolines in supercritical carbon dioxide, 2007. Green Chemistry. 9:948-953., Number 9 Abstract

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Jimenez, A, Pinheiro C, Parola AJ, Maestri M, Pina F.  2007.  The chemistry of 6-hydroxyflavylium: zwitterionic base and p-quinoidal chalcones. A multiswitchable system operated by proton, electron and photon inputs, 2007. Photochemical & Photobiological Sciences. 6:372-380. AbstractWebsite

The complex network of chemical reactions of the compound 6-hydroxyflavylium perchlorate was studied by different techniques including UV-vis absorption spectrophotometry, stopped-flow, electrochemistry, and photochemistry. The network is characterized by the formation of a very reactive zwitterionic base as well as by p-quinoidal chalcones. The trans-chalcone is metastable in very acidic solutions and exhibits reversible redox reactions, allowing to introduce for the first time in the flavylium network an electrochemical input.

Parola, AJ, Pereira P, Pina F, Maestri M.  2007.  Effect of SDS micelles on the reactivity of 4 '-methoxyflavylium ion: A stopped-flow and photochemical study, 2007. Journal of Photochemistry and Photobiology a-Chemistry. 185:383-390. AbstractWebsite

The network of chemical reactions of the compound 4'-methoxyflavylium was studied in the presence of SDS micelles, using stopped-flow, UV-vis absorption and flash photolysis techniques. The results were compared with analogous experiments carried out in water. The large stabilization of the flavylium cation onto the micelles was proven to be due to an increase in the rate of the dehydration reaction, rather than a decrease of the hydration reaction; the cis-trans isomerisation of the chalcone was not affected by the micelles. It is shown that SDS micelles can be considered as an external stimulus capable of changing the system from one state to another. (c) 2006 Elsevier B.V. All rights reserved.

Gomes, R, Parola AJ, Laia CAT, Pina F.  2007.  Efficient photochromism from the network of chemical reactions of 7,4 '-dihydroxyflavylium in CTAB micelles, 2007. Photochemical & Photobiological Sciences. 6:1003-1009. AbstractWebsite

Differently from water,effcient photochromism with a strong colour contrast has been observed for the multistate compound 7,4'- dihydroxyflavylium in the presence of cetyl trimethylammonium bromide ( CTAB) micelles. Two states are responsible for the photochromism: trans-chalcone ( inside the micelle) in the dark, and flavylium cation, AH(+), ( in bulk water) upon irradiation. The kinetics of the system was characterized by. ash photolysis and pH jumps. Evidence that the photochemical process leading to AH(+) occurs in the micelle was achieved. The best colour contrast is obtained at pH = 1.5, from a solution practically colourless in the dark, to an intense yellow upon irradiation ( quantum yield 0.4). The system is completely reversible with a lifetime of 38 min at room temperature, and exhibits a reasonable stability. A kinetic model capable of fitting the data from thermal entrance of the compound into the micelle, its ejection to bulk water upon irradiation and quantum yields of the photochemical process is proposed.

Melo, MJ, Sousa M, Parola AJ, de Melo JSS, Catarino F, Marcalo J, Pina F.  2007.  Identification of 7,4 '-dihydroxy-5-methoxyflavylium in "Dragon's blood": To be or not to be an anthocyanin, 2007. Chemistry-a European Journal. 13:1417-1422. AbstractWebsite

The compound 7,4'-dihydroxy-5-methoxyflavylium (dracoflavylium) was identified as the major red colorant in samples of the resin "dragon's blood", extracted from the tree Dracaena draco. The complex network of reversible chemical reactions that dracoflavylium undergoes in aqueous solution is fully described; for the first time, all the equilibrium constants that enable a complete characterisation of the system have been obtained (K'(a)=1.6 x 10(-4), K-a1 = 1.0 x 10(-4), K-a2 = 3.2 x 10(-8), K-Ct1 = 1.0 x 10(-7), K-Ct2 = 1.3 x 10(-10)). It is concluded that the red colour is due to a stable quinoid base, A, which is the major species at pH 4-7. It is further shown that this compound does not fit the commonly accepted definitions of anthocyanidin nor 3-deoxyanthocyanidin. Similarly to synthetic flavylium salts, the natural compound 7,4'-dihydroxy-5-methoxyflavylium gives rise to several species (multistate system) reversibly interconverted by external stimuli, such as pH.

Laia, CAT, Parola AJ, Folgosa F, Pina F.  2007.  Multistate reaction kinetics of 6-hydroxy-4 '-(dimethylamino)flavylium driven by pH. A stopped-flow study, 2007. Organic & Biomolecular Chemistry. 5:69-77. AbstractWebsite

The synthetic flavylium salt 6-hydroxy-4'-(dimethylamino)flavylium hexa. uorophosphate displays a set of pH-driven chemical reactions in aqueous solutions, involving the formation of hemiketal species and chalcones with cis and trans configurations. Such reactions were studied by steady-state and transient UV-Vis spectroscopy and by stopped-flow techniques. A novel and more generalized kinetic scheme is developed, in order to take account of possible acid/base pairs that occur in the network of chemical reactions as the pH is changed. It is found that the formation of the hemiketal species by hydration of the. avylium is slow, and it is not possible to isolate each process that leads to the formation of the cis-chalcone ( hydration and tautomerization reactions). The cis/trans isomerization reaction of cis-chalcone is slow, and the system takes several hours to reach equilibrium after a pH jump at room temperature. In basic conditions, negatively charged trans-chalcones are dominant. Comparison with other. avylium compounds shows that the hydration process is affected mainly by the amino group, while the hydroxyl group influences the tautomerization and isomerization reactions.

Pina, F, Parola AJ, Melo MJ, Laia CAT, Afonso CAM.  2007.  Photochromism of 7-(N, N-diethylamino) 4 '-hydroxyflavylium in a water-ionic liquid biphasic system, 2007. Chemical Communications. :1608-1610. AbstractWebsite

Photochromism of trans-4-(N,N-diethylamino)-2,4'-dihydroxychalcone, with formation of the photoproduct 7-(N,N-diethylamino)-4'-hydroxyflavylium, is promoted in the ionic liquid phase of a water/[bmim][PF6] biphasic system.

Gomes, R, Parola AJ, Laia CAT, Pina F.  2007.  Promoting photochromism on flavylium derived 2-hydroxychalcones in aqueous solutions by addition of CTAB micelles, 2007. Journal of Physical Chemistry B. 111:12059-12065. AbstractWebsite

A strategy to obtain photochromism from the network of chemical reactions originated by flavyliurn compounds in solution is described. This strategy is particularly useful for flavyliurn salts bearing amino groups which give rise to a variety of beautiful colors but lack photochemistry in water. The trans-chalcone of 7-(N,Ndiethylamino)-4'-hydroxyflavylium interacts strongly with CTAB micelles defining a yellow dark state. Upon irradiation, the system switches to a pink-red state emerging from the flavylium cation that is formed inside the micelle and ejected to the bulk aqueous phase. The photochemical product reverts back to the transchalcone adduct with the micelle in the dark. The thermodynamics as well as the kinetics of the photochromic system were studied in detail. The best color contrast is obtained at pH = 4.25 with (D = 0.001 and a recovery lifetime of approximately 3 h. This photochromic system works with no need of changing the pH, which constitutes an important improvement over previously described systems dependent on pH jumps.

de Melo, JS, Takato S, Sousa M, Melo MJ, Parola AJ.  2007.  Revisiting Perkin's dye(s): the spectroscopy and photophysics of two new mauveine compounds (B2 and C), 2007. Chemical Communications. :2624-2626. AbstractWebsite

Two new components have been identified in an early sample prepared according to the original recipe of Perkin, and perhaps even by Perkin himself around 1860 - a new isomer of Perkin's mauveine B (designated as mauveine B2) together with a new mauveine compound (mauveine C) - and these compounds were synthesized again using starting materials chosen to reproduce Perkin's original synthesis and isolated by HPLC-DAD, identified by H-1 NMR, MS and their spectroscopic (UV/Vis and emission) and photophysical behaviour investigated.

Cordeiro, FM, Carreira RJ, Rial-Otero R, Rivas GM, Moura I, Capelo J-L.  2007.  Simplifying sample handling for protein identification by peptide mass fingerprint using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, 2007. Rapid Communications in Mass Spectrometry. 21:3269-3278., Number 20 AbstractWebsite

An ultrasonic bath, an ultrasonic probe and a sonoreactor were used to speed up the kinetics of the reactions involved in each step of the sample handling for in-gel protein identification by peptide mass fingerprint, PMF, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). The following steps were successfully accelerated using ultrasonic energy: gel washing, protein reduction, and protein alkylation. As a result, a reduction comprising 80% to 90% of the total time involved in the classic approach was achieved. In addition the sample handling was also drastically simplified. The number of peptides identified and the protein sequence coverage obtained for the new procedure were comparable to those obtained with the traditional sample treatment for the following protein standards: glycogen phosphorylase b, BSA, ovalbumin, carbonic anhydrase, trypsin inhibitor and alpha-lactalbumin. Finally, as a proof of the procedure, specific proteins were identified from complex protein mixtures obtained from three different sulphate- reducing bacteria: Desulfovibrio, desulfuricans G20, Desulfuvibrio gigas NCIB 9332, and Desulfuvibrio desulfuricans ATCC 27774. Copyright (c) 2007 John Wiley & Sons, Ltd.

Roque, A, Lima JC, Parola AJ, Pina F.  2007.  Substitution and solvent effects in the chalcones isomerization barrier of flavylium photochromic systems, 2007. Photochemical & Photobiological Sciences. 6:381-385. AbstractWebsite

Useful application of photochromic compounds as optical memories implies the existence of a large kinetic barrier between the forms interconverted by light. In the case of flavylium salts, the ground state isomerization barrier between the photoisomerizable chalcone isomers is shown to correlate with the electron donating ability of the substituents, measured by their effects in the H-1 NMR chemical shifts of the aromatic protons. Substitution with electron donating groups in ring A lowers the barrier while substitution at ring B has the opposite effect. However, in water, the observed increase is higher than expected in the case of compound 4', 9-dihydroxychalcone when compared with the analogous 4'-dimethylamino-9-hydroxychalcone, containing a better electron donating group in the same position. Our interpretation is that the water network is providing an efficient pathway to form tautomers. In acetonitrile, unlike water, the expected order is indeed observed: E-a( 4', 9-dihydroxychalcone) = 60 kJ mol(-1) < E-a ( 4'-dimethylamino-9-hydroxychalcone) = 69 kJ mol(-1).