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Sulphate-reducing bacteria have a wide variety of periplasmic cytochromes involved in electron transfer from the periplasm to the cytoplasm. HmcA is a high molecular mass cytochrome of 550 amino acid residues that harbours 16 c-type heme groups. We report the crystal structure of HmcA isolated from the periplasm of Desulfovibrio gigas. Crystals were grown. using polyethylene glycol 8K and zinc acetate, and diffracted beyond 2.1 angstrom resolution. A multiple-wavelength anomalous dispersion experiment at the iron absorption edge enabled us to obtain good-quality phases for structure solution and model building. DgHmcA has a V-shape architecture, already observed in HmcA isolated from Desulfovibrio vulgaris Hildenborough. The presence of an oligosaccharide molecule covalently bound to an Asn residue was observed in the electron density maps of DgHmcA and confirmed by mass spectrometry. Three modified monosaccharides appear at the highly hydrophobic vertex, possibly acting as an anchor of the protein to the cytoplasmic membrane. (c) 2007 Elsevier Ltd. All rights reserved.

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We report the 98% assignment of the apo-form of an orange protein, containing a novel Mo-Cu cluster isolated from Desulfovibrio gigas. This protein presents a region where backbone amide protons exchange fast with bulk solvent becoming undetectable. These residues were assigned using 13C-detection experiments.

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Recent fieldwork in the Namibe province in southern Angola yielded cranial and postcranial elements of at least two individuals of the rare and enigmatic mosasaur Halisaurus from a single small excavation. The genus Halisaurus is unique in retaining a primitive configuration of the temporal arcade, specifically a broad, vertically oriented contact between the parietal and the supratemporal. The supratemporal is broadly sutured to the opisthotic and prootic, unlike the condition in varanoids in which the simple lunate element lies between the parietal ramus and the squamosal and does not form a sutural contact with the opisthotic or prootic, but as in other halisaurines retains a plesiomorphic, vertically oriented contact with the parietal rami. The squamosal is lightly built and broadly arched as in Varanus. Comparison with known halisaurines indicates the new material is referable to the species Halisaurus arambourgi.
The locality that yielded the new specimens has also yielded a large number of isolated teeth, bones, articulated, and associated skeletons of Mosasaurus, Prognathodon, Globidens, and Plioplatecarpus, which with Halisaurus comprise a mosasaur assemblage most similar to that reported from the Maastrichtian of Morocco.

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The record of ornithischian dinosaurs from Portugal is substantial but incomplete in terms of our understanding of taxonomic composition and details of the anatomy of many forms. New data and reinterpretation of these forms are provided. The basal thyreophoran from the Lower Jurassic (the nomen dubium “Lusitanosaurus liasicus”) is the most primitive dinosaur from Iberia. Concerning the Late Jurassic, new material from the Lourinhã Formation (Kimmeridgian/Tithonian) referable to the stegosaur Dacentrurus provides additional information on the systematic position and osteology.
The new material shows two rows of paired triangular plates, with a notch in the anterior rim. A maxillary of an ankylosaur from the Vale Frades (Lourinhã Fm.) is here reported, but cannot be referable to Dracopelta, the only ankylosaur genus currently known from Portugal. The ornithopod Alocodon kuehnei reported as Middle Jurassic (Callovian) is probably Oxfordian in age. A right dentary (ML768 from Zimbral) from the Lourinhã Formation, Kimmeridgian/Tithonian, and shares affinities with Dryosaurus but possesses more denticulation and no secondary ridges, suggesting the occurrence of a new or unreported species for the Late Jurassic of Portugal, which is here tentatively ascribed to aff. Dryosaurus sp. In summary, the Late Jurassic ornithischians species/genera from Portugal include Dacentrurus armatus, Stegosaurus cf. ungulatus, Dracopelta zbyszewskii, Phyllodon henkeli, Hypsilophodon sp., Alocodon kuehnei, Trimucrodon cuneatus, aff. Dryosaurus and Draconyx loureiroi. The Lower Cretaceous (Hauterivian / Barremian) of Praia das Aguncheiras, in Cabo Espichel, provided a partial left maxillary (CPGP.1.99.7) of a basal iguanodontian that shows affinities with Camptosaurus, and is tentatively assigned to this genus. The maxillary teeth denticles differ from Iguanodon or other Iguanodontoidea because not show mammillations. More material is necessary to validate but, to be true, that would confirm the presence of this genus in the lower Cretaceous. The Iguanodon has been well reported in the Lower Cretaceous of Cabo Espichel.

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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).

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).

The two new pincer azomethine-thiophene ligands (N,NE',N,NE')-N,N'-(thiophene-2,5-diylbis(methan-1-yl-1-ylidene))bis(naphathalen-2-ylmethanamine) (L1) and (E)-(4,6-dihydropyren-1-yl)-N-((5-((E)-(pyren-1-ylmethylimino)ethyl)thiophen-2-yl)methylene)methanamine (L2), their absorption, fluorescence and MALDI-TOF-MS spectroscopic studies are described. The two systems synthesised combine the emissive probes pyrene and naphthyl with the good chelating properties of a tridentate SN2 donor-set from a thiophene Schiff-base ligand. Both ligands gave analytically pure solid complexes with Ni(II) and Pd(II) salts. The bichromophoric pyrene derivative L2 presents two emission bands in solution, one corresponding to the monomer species and a red-shifted band attributable to the intramolecular excimer. Ni(II) and Pd(II) complexation affects the conformation in solution, increasing the monomer emission at the expense of the excimer band; this effect could be explored in metal ion sensing. System L1 behaves as a non emissive probe. In situ complexation reactions followed by MALDI-TOF-MS spectrometry without matrix support have also been performed; these experiments show that L1 could be a potential chemosensor for Ni(II) and Pd(11). (c) 2007 Elsevier B.V. All rights reserved.

The electric and magnetic properties of high temperature superconductors and the possibility to cool them by cheap liquid nitrogen makes them attractive in power applications. An all superconducting linear synchronous motor is presented in this paper in order to quantify the benefits and disadvantages of such applications. The term ?all superconducting? is related with the absence of copper conductors and iron parts. Certain characteristics of the superconducting materials impose severe restrictions when used, e.g., as armature windings. A numerical method for deriving the thrust and lift forces developed in such a motor, driven by a typical current inverter, is presented.

We present a study of the growth of silver clusters on a TiO2(110) substrate in ultra- high vacuum. The growth is monitored in situ by Low Energy Ion Scattering (LEIS) using He+ scattering and X-ray Photoelectron Spectroscopy (XPS) and ex situ by scanning electron microscopy (SEM). Experimental results show that the deposition rate, the substrate temperature and the annealing temperature are key parameters for controlling the size and morphology of the Ag clusters. By changing the deposition rate, the mean cluster diameter can vary from 5 to 20 nm. The growth of Ag at low substrate temperature shows a transition from quasi 2D flat islands to a 3D growth mode at submonolayer coverage. The substrate was annealed at different temperatures and the clusters shape controlled from a quasi 2D flat island to 3D sharp islands with a maximum substrate exposure, prior to cluster desorption.

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