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2012
Dias, RJ, Vale TM, Lourenço JM.  2012.  Efficient Support for In-Place Metadata in Transactional Memory. Euro-Par 2012 Parallel Processing. 7484(Kaklamanis, Christos, Papatheodorou, Theodore, Spirakis, PaulG., Eds.).:589–600., Rhodes, Greece: Springer Berlin Heidelberg Abstract2012-europar.pdf

Implementations of Software Transactional Memory (STM) algorithms associate metadata with the memory locations accessed during a transaction’s lifetime. This metadata may be stored either in-place, by wrapping every memory cell in a container that includes the memory cell itself and the corresponding metadata; or out-place (also called external), by resorting to a mapping function that associates the memory cell address with an external table entry containing the corresponding metadata. The implementation techniques for these two approaches are very different and each STM framework is usually biased towards one of them, only allowing the efficient implementation of STM algorithms following that approach, hence inhibiting the fair comparison with STM algorithms falling into the other. In this paper we introduce a technique to implement in-place metadata that does not wrap memory cells, thus overcoming the bias by allowing STM algorithms to directly access the transactional metadata. The proposed technique is available as an extension to the DeuceSTM framework, and enables the efficient implementation of a wide range of STM algorithms and their fair (unbiased) comparison in a common STM infrastructure. We illustrate the benefits of our approach by analyzing its impact in two popular TM algorithms with two different transactional workloads, TL2 and multi-versioning, with bias to out-place and in-place respectively.

Gokulakrishnan, V., Parthiban, S., Elangovan, E., Jeganathan, K., Kanjilal, D., Asokan, K., Martins, Fortunato, Ramamurthi K.  2012.  Investigation of O7+ swift heavy ion irradiation on molybdenum doped indium oxide thin films. Radiation Physics and Chemistry. 81(6):589-593.
Kuckova, S, et al.  2012.  Protein identification and localization using mass spectrometry and staining tests in cross-sections of polychrome samples. Journal of Cultural Heritage. AbstractWebsite

The identification and localization of the proteinaceous binders are essential issues in studies of painting materials and techniques, for further proposing valid restoration and conservation treatments of the painted or polychrome works of art. The challenge for analytical chemists and conservation scientists is the availability of methods able to simultaneously identify and map the presence of the binders in the multilayered structure of a sample and the possibility to use a very low amount of sample from the studied art object (considering also the criteria of minimum sampling). These methods should be fast, reproducible in different artefacts and in case of mixture of protein-based binders with other non-proteinaceous constituents (oils, resins, waxes, gums etc.) and also economical (both in terms of materials and time consume). In this context, the present paper proposes an innovative protocol of investigation using two complementary techniques – Matrix-Assisted Laser Desorption/Ionisation – Time of Flight Mass Spectrometry (MALDI-TOF MS) and staining tests (one visible and one fluorescent stain) assisted by Optical Microscopy (OM) on cross-section of samples – for the simultaneous identification and mapping of protein – and oil-based binders in paint materials. The novelty is based on the use of MALDI-TOF MS on cross-sections of paints together with a fluorescent stain for protein identification and mapping (mainly used in the area of proteomics) complementing the use of a traditional visible stain for oil-based material identification. The protocol was successfully applied on several samples taken from a Czech medieval polychrome sculpture, entitled “The Mourning of Jesus Christ” (16th century) belonging to the Moravian Gallery (Brno).

SCUTARU, G, SANDU F, COCORADA E, PAVALACHE M, KRISTALY D, Gomes L, Coito F, MÖRSKY-LINDQUIST AK, CSEREY S, DASC{\u A}LU M, Others.  2012.  RELAZIONE SUGLI ASPETTI FORMATIVI. Abstract

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Kowacz, M, Mukhopadhyay A, Carvalho AL, Esperanca J, Romao MJ, Rebelo LPN.  2012.  Hofmeister effects of ionic liquids in protein crystallization: Direct and water-mediated interactions. Crystengcomm. 14:4912-4921., Number 15 AbstractWebsite

We have performed experiments on the crystallization of two low molecular weight, positively charged proteins, lysozyme and ribonuclease A, using ionic liquids as either crystallization additives or, in particular cases, as precipitating agents. The ionic liquids (ILs) have been ordered according to their salting-in/out ability and the relative position of these ionic liquids in this ranking has been rationalized by considering their hydration properties (positive-negative, hydrophobic-hydrophilic). The ability to screen the effective charge of cationic proteins and aid protein nucleation (salting-out) has been shown to be superior for large polarizable anions with low charge density, negatively hydrated-Cl-, Br-, [SCN](-), methane-[C1SO3](-) and ethanesulfonates [C2SO3](-), than for anions with a relatively stable hydration shell, positively hydrated-lactate [Lac](-), butylsulfonate [C4SO3](-) and acetate [Ac](-). Upon increasing the background salt concentration, where electrostatic interactions are already effectively screened, the ability of the IL ions to stabilize proteins in solution (salting-in) has been shown to increase as the ions are likely to migrate to the non-polar protein surface and lower protein-water interfacial tension. This tendency is enhanced as the focus moves from those ions with positively hydrated hydrophilic compartments (e. g. [Ac](-)) to those with negatively hydrated groups (e. g. [C1SO3](-)) and the prevailing hydrophobic hydration (e. g. [C4SO3](-)). The observed inversion in the relative effect of ILs on protein crystallization with increasing ionic strength of the aqueous media has been interpreted as the differing effects of ion adsorption: charge screening and interfacial tension modification. Moreover, this work can further help in our understanding of the influence of ionic liquids on conformational changes of biomacromolecules in solution. Identification of the specific incorporation sites for choline and acetate ions, localized in two lysozyme crystals grown in pure IL solutions without any buffer or inorganic precipitant, can give us some insight into the role of the ionic liquid ions in protein structure development.

2011
Mukhopadhyay, A, Kladova AV, Bursakov SA, Gavel OY, Calvete JJ, Shnyrov VL, Moura I, Moura JJ, Romao MJ, Trincao J.  2011.  Crystal structure of the zinc-, cobalt-, and iron-containing adenylate kinase from Desulfovibrio gigas: a novel metal-containing adenylate kinase from Gram-negative bacteria, Jan. J Biol Inorg Chem. 16:51-61., Number 1 AbstractWebsite

Adenylate kinases (AK) from Gram-negative bacteria are generally devoid of metal ions in their LID domain. However, three metal ions, zinc, cobalt, and iron, have been found in AK from Gram-negative bacteria. Crystal structures of substrate-free AK from Desulfovibrio gigas with three different metal ions (Zn(2+), Zn-AK; Co(2+), Co-AK; and Fe(2+), Fe-AK) bound in its LID domain have been determined by X-ray crystallography to resolutions 1.8, 2.0, and 3.0 A, respectively. The zinc and iron forms of the enzyme were crystallized in space group I222, whereas the cobalt-form crystals were C2. The presence of the metals was confirmed by calculation of anomalous difference maps and by X-ray fluorescence scans. The work presented here is the first report of a structure of a metal-containing AK from a Gram-negative bacterium. The native enzyme was crystallized, and only zinc was detected in the LID domain. Co-AK and Fe-AK were obtained by overexpressing the protein in Escherichia coli. Zn-AK and Fe-AK crystallized as monomers in the asymmetric unit, whereas Co-AK crystallized as a dimer. Nevertheless, all three crystal structures are very similar to each other, with the same LID domain topology, the only change being the presence of the different metal atoms. In the absence of any substrate, the LID domain of all holoforms of AK was present in a fully open conformational state. Normal mode analysis was performed to predict fluctuations of the LID domain along the catalytic pathway.

Seixas, J, Simões S, Kanudia A, Gargiulo M, Dias L, Gouveia JP, Fortes P.  2011.  Electric Vehicles in the European Union: Conditions for Success, Impacts on the Power System and on CO2 Emissions, 6-8 July. IEW - International Energy Workshop 2011,. , Standford, USA.
Borges, JP, Godinho MH, Figueirinhas JL, de Pinho MN, Belgacem MN.  2011.  All-cellulosic based composites. Cellulose Fibers: Bio-and Nano-Polymer Composites. (Susheel Kalia, B. S. Kaith, Inderjeet Kaur, Eds.).:399–421.: Springer Berlin Heidelberg Abstract

The use of cellulosic fibers as load bearing constituents in composite materials has increased over the last decade due to their relative cheapness compared to conventional materials such as glass and aramid fibers, their ability to recycle, and because they compete well in terms of strength per weight of material. All-cellulosic based composites prepared from cellulose derivatives based matrices and microcrystalline cellulosic fibers made by direct coupling between fibers and matrix present interesting mechanical and gas permeation properties, thus being potential candidates for packaging materials. Both the cellulosic matrix and the reinforcing fibers are biocompatible and widely used in the pharmaceutical industry, which is very important for the envisaged application. In addition to their biocompatibility, cellulosic systems have the ability to form both thermotropic and lyotropic chiral nematic phases, and the composites produced from the latter show improved mechanical properties due to fiber orientation induced by the anisotropic matrix. The preparation and characterization (morphological, topographical, mechanical, gas barrier properties) of all-cellulosic based composites are described in this chapter.

Parthiban, S, Elangovan E, Ramamurthi K, Kanjilal D, Asokan K, Martins R, Fortunato E.  2011.  Effect of Li3+ heavy ion irradiation on the Mo doped In2O3 thin films prepared by spray pyrolysis technique. J. Phys. D-Appl. Phys.. 44(085404)
Lewandowski, B, Listkowski A, Petrova K, Jarosz S.  2011.  Functionalisation of terminal positions of sucrose - Part II: Preparation of 1’,2,3,3’,4,4’-hexa-O-benzyl sucrose and 6,6’-bis-O-(2-hydroxyethyl)-1’,2,3,3’,4,4’-hexa-O-benzylsucrose. Carbohydrate Chemistry: Proven Synthetic Methods. (P. Kovac, Ed.).:407-425., New York: CRC Press, Taylor & Francis Group
Almeida, R, Ortigueira MD, Batista AG, Ktonas P.  2011.  Sleep Spindles: Decomposition, Parameterization and Applications. 19th IEEE Conference on Signal Processing and Communications Applications. Abstract

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de Almeida, SF, Grosso AR, Koch F, Fenouil R, Carvalho S, Andrade J, Levezinho H, Gut M, Eick D, Gut I, Andrau J-C, Ferrier P, Carmo-fonseca M.  2011.  Splicing enhances recruitment of methyltransferase HYPB/Setd2 and methylation of histone H3 Lys36.. Nature structural & molecular biology. 18:977–983., Number 9: Nature Publishing Group AbstractWebsite

Several lines of recent evidence support a role for chromatin in splicing regulation. Here, we show that splicing can also contribute to histone modification, which implies bidirectional communication between epigenetic mechanisms and RNA processing. Genome-wide analysis of histone methylation in human cell lines and mouse primary T cells reveals that intron-containing genes are preferentially marked with histone H3 Lys36 trimethylation (H3K36me3) relative to intronless genes. In intron-containing genes, H3K36me3 marking is proportional to transcriptional activity, whereas in intronless genes, H3K36me3 is always detected at much lower levels. Furthermore, splicing inhibition impairs recruitment of H3K36 methyltransferase HYPB (also known as Setd2) and reduces H3K36me3, whereas splicing activation has the opposite effect. Moreover, the increase of H3K36me3 correlates with the length of the first intron, consistent with the view that splicing enhances H3 methylation. We propose that splicing is mechanistically coupled to recruitment of HYPB/Setd2 to elongating RNA polymerase II.

Mukhopadhyay, A, Kladova AV, Bursakov SA, Gavel YO, Calvete JJ, Shnyrov VL, Moura I, Moura JJG, Romao MJ, Trincao J.  2011.  Crystal structure of the zinc-, cobalt-, and iron-containing adenylate kinase from Desulfovibrio gigas: a novel metal-containing adenylate kinase from Gram-negative bacteria. Journal of Biological Inorganic Chemistry. 16:51-61., Number 1 AbstractWebsite
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Almeida, R, Ortigueira MD, Batista AG, Ktonas P.  2011.  Sleep Spindles: Decomposition, Parameterization and Applications. 19th IEEE Conference on Signal Processing and Communications Applications. Abstract
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2010
Nierling, L, Krings B.  2010.  {The impact of global forces on the individual: empirical evidence from the German clothing industry}, Aug. , Number 08/2010: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

Starting from theoretical perspectives on globalisation, the following article analyses how current working conditions are affected by globalisation processes. For this purpose, recent developments in the German clothing sector are traced back to the power of economic globalisation processes. Characterising the German clothing sector as pioneer in economic globalisation, we use empirical findings to illustrate how current processes of globalisation influence the work place: At organisational level, corporate strategies aim at rationalisation, standardisation and flexibilisation of work in order to response to the economic pressure of global markets. At individual level these strategies, in turn, speed up working processes and intensify working processes for the employees. Although these developments form strong trends, we conclude that the local embeddedness of companies is still of high importance with regard to organisational and individual consequences of globalisation.

Barquinha, P, Pereira L, Goncalves G, Kuscer D, Kosec M, Vila A, Olziersky A, Morante JR, Martins R, Fortunato E.  2010.  Low-temperature sputtered mixtures of high-kappa and high bandgap dielectrics for GIZO TFTs. J. Soc. Inf. Disp. . 18
Inoue, K, Qian X, Morgado L, Kim B-C, Mester T, Izallalen M, Salgueiro CA, Lovley DR.  2010.  Purification and Characterization of OmcZ, an Outer-Surface, Octaheme c-Type Cytochrome Essential for Optimal Current Production by Geobacter sulfurreducens. Applied and Environmental Microbiology. 76(12):3999-4007. AbstractWebsite

Previous studies have demonstrated that Geobacter sulfurreducens requires the c-type cytochrome OmcZ, which is present in large (OmcZL; 50-kDa) and small (OmcZS; 30-kDa) forms, for optimal current production in microbial fuel cells. This protein was further characterized to aid in understanding its role in current production. Subcellular-localization studies suggested that OmcZS was the predominant extracellular form of OmcZ. N- and C-terminal amino acid sequence analysis of purified OmcZS and molecular weight measurements indicated that OmcZS is a cleaved product of OmcZL retaining all 8 hemes, including 1 heme with the unusual c-type heme-binding motif CX14CH. The purified OmcZS was remarkably thermally stable (thermal-denaturing temperature, 94.2°C). Redox titration analysis revealed that the midpoint reduction potential of OmcZS is approximately −220 mV (versus the standard hydrogen electrode [SHE]) with nonequivalent heme groups that cover a large reduction potential range (−420 to −60 mV). OmcZS transferred electrons in vitro to a diversity of potential extracellular electron acceptors, such as Fe(III) citrate, U(VI), Cr(VI), Au(III), Mn(IV) oxide, and the humic substance analogue anthraquinone-2,6-disulfonate, but not Fe(III) oxide. The biochemical properties and extracellular localization of OmcZ suggest that it is well suited for promoting electron transfer in current-producing biofilms of G. sulfurreducens.

Lehmann, M, Kohn C, Figueirinhas JL, Feio G, Cruz C, Dong RY.  2010.  Biaxial nematic mesophases from shape-persistent mesogens with a fluorenone bending unit. Chemistry. 16:8275-9., Number 28 AbstractWebsite
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Monteiro, B, Cunha-Silva L, Gago S, Klinowski J, Almeida Paz FA, Rocha J, Goncalves IS, Pillinger M.  2010.  Crystal and supramolecular structures of dioxomolybdenum(VI) and dioxotungsten(VI) complexes of dihydroxybenzoic acids. Polyhedron. 29:719-730., Number 2 AbstractWebsite
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Kundu, S, Feio G, Pinto LFV, Almeida PL, Figueirinhas JL, Godinho MH.  2010.  Deuterium NMR Study of Orientational Order in Cellulosic Network Microfibers. Macromolecules. 43:5749-5755., Number 13 AbstractWebsite

Deuterium NMR was used to investigate the orientational order in a composite cellulosic formed by liquid crystalline acetoxypropylcellulose (A PC) and demented nematic 4'-penty1-4-cyanobiphenyl (5CB-4 alpha d(2)) with the per centage of 85% A PC by weight Three forms of the composite including electro spun microfibers, thin film and bulk samples were analyzed The NMR results initially suggest two distinct scenarios, one whet e the 503-alpha d(2), is confined to small droplets with dimensions smaller than the magnetic coherence length and the other where the 503-alpha d(2) molecules arc aligned with the A PC network chains Polarized optical microscopy (POW from thin film samples along with all the NMR results show the presence of 5CB-alpha d(2) droplets in the composite systems with a nematic wetting layer at the APC-5CB-alpha d(2) interface that experiences and order disorder transition driven by the polymer network N-I transition The characterization of the APC network I-N transition shows a pronounced subcritical behavior within a heterogeneity scenario

Figueirinhas, JL, Feio G, Cruz C, Lehmann M, Kohn C, Dong RY.  2010.  Nuclear magnetic resonance spectroscopic investigations of phase biaxiality in the nematic glass of a shape-persistent V-shaped mesogen. J Chem Phys. 133:174509., Number 17 AbstractWebsite

Deuterium and carbon-13 NMR spectroscopy were used to study both the high temperature uniaxial nematic and the low temperature biaxial nematic glass of a shape-persistent V-shaped mesogen. It was found that biaxial ordering determined in the domains of the latter has symmetry lower than D(2h) and is compatible with C(2h) symmetry or lower. In particular, elements of the ordering matrix including biaxial phase order parameters were determined from (2)H NMR at two temperatures, one just below the glass transition, and the other deep inside the biaxial glass, which allowed for the characterization of the dominant molecular motions at these temperatures. (13)C NMR magic angle spinning sideband patterns, collected both in the high temperature nematic phase and in the nematic glass, clearly show the difference between them in terms of the phase symmetry.

2009
Kladova, AV, Gavel OY, Mukhopaadhyay A, Boer DR, Teixeira S, Shnyrov VL, Moura I, Moura JJ, Romao MJ, Trincao J, Bursakov SA.  2009.  Cobalt-, zinc- and iron-bound forms of adenylate kinase (AK) from the sulfate-reducing bacterium Desulfovibrio gigas: purification, crystallization and preliminary X-ray diffraction analysis, Sep 1. Acta Crystallogr Sect F Struct Biol Cryst Commun. 65:926-9., Number Pt 9 AbstractWebsite

Adenylate kinase (AK; ATP:AMP phosphotransferase; EC 2.7.4.3) is involved in the reversible transfer of the terminal phosphate group from ATP to AMP. AKs contribute to the maintenance of a constant level of cellular adenine nucleotides, which is necessary for the energetic metabolism of the cell. Three metal ions, cobalt, zinc and iron(II), have been reported to be present in AKs from some Gram-negative bacteria. Native zinc-containing AK from Desulfovibrio gigas was purified to homogeneity and crystallized. The crystals diffracted to beyond 1.8 A resolution. Furthermore, cobalt- and iron-containing crystal forms of recombinant AK were also obtained and diffracted to 2.0 and 3.0 A resolution, respectively. Zn(2+)-AK and Fe(2+)-AK crystallized in space group I222 with similar unit-cell parameters, whereas Co(2+)-AK crystallized in space group C2; a monomer was present in the asymmetric unit for both the Zn(2+)-AK and Fe(2+)-AK forms and a dimer was present for the Co(2+)-AK form. The structures of the three metal-bound forms of AK will provide new insights into the role and selectivity of the metal in these enzymes.

Conrath, K, Pereira AS, Martins CE, Timoteo CG, Tavares P, Spinelli S, Kinne J, Flaudrops C, Cambillau C, Muyldermans S, Moura I, Moura JJ, Tegoni M, Desmyter A.  2009.  Camelid nanobodies raised against an integral membrane enzyme, nitric oxide reductase, Mar. Protein Sci. 18:619-28., Number 3 AbstractWebsite

Nitric Oxide Reductase (NOR) is an integral membrane protein performing the reduction of NO to N(2)O. NOR is composed of two subunits: the large one (NorB) is a bundle of 12 transmembrane helices (TMH). It contains a b type heme and a binuclear iron site, which is believed to be the catalytic site, comprising a heme b and a non-hemic iron. The small subunit (NorC) harbors a cytochrome c and is attached to the membrane through a unique TMH. With the aim to perform structural and functional studies of NOR, we have immunized dromedaries with NOR and produced several antibody fragments of the heavy chain (VHHs, also known as nanobodies). These fragments have been used to develop a faster NOR purification procedure, to proceed to crystallization assays and to analyze the electron transfer of electron donors. BIAcore experiments have revealed that up to three VHHs can bind concomitantly to NOR with affinities in the nanomolar range. This is the first example of the use of VHHs with an integral membrane protein. Our results indicate that VHHs are able to recognize with high affinity distinct epitopes on this class of proteins, and can be used as versatile and valuable tool for purification, functional study and crystallization of integral membrane proteins.

Rivas, MG, Carepo MS, Mota CS, Korbas M, Durand MC, Lopes AT, Brondino CD, Pereira AS, George GN, Dolla A, Moura JJ, Moura I.  2009.  Molybdenum induces the expression of a protein containing a new heterometallic Mo-Fe cluster in Desulfovibrio alaskensis, Feb 10. Biochemistry. 48:873-82., Number 5 AbstractWebsite

The characterization of a novel Mo-Fe protein (MorP) associated with a system that responds to Mo in Desulfovibrio alaskensis is reported. Biochemical characterization shows that MorP is a periplasmic homomultimer of high molecular weight (260 +/- 13 kDa) consisting of 16-18 monomers of 15321.1 +/- 0.5 Da. The UV/visible absorption spectrum of the as-isolated protein shows absorption peaks around 280, 320, and 570 nm with extinction coefficients of 18700, 12800, and 5000 M(-1) cm(-1), respectively. Metal content, EXAFS data and DFT calculations support the presence of a Mo-2S-[2Fe-2S]-2S-Mo cluster never reported before. Analysis of the available genomes from Desulfovibrio species shows that the MorP encoding gene is located downstream of a sensor and a regulator gene. This type of gene arrangement, called two component system, is used by the cell to regulate diverse physiological processes in response to changes in environmental conditions. Increase of both gene expression and protein production was observed when cells were cultured in the presence of 45 microM molybdenum. Involvement of this system in Mo tolerance of sulfate reducing bacteria is proposed.

Krings, B.  2009.  {Global restructuring and its effects on occupations: towards a new division of labor?}, Dec , Number 12/2009: Universidade Nova de Lisboa, IET/CICS.NOVA-Interdisciplinary Centre on Social Sciences, Faculty of Science and Technology Abstract

The following contribution considers whether global restructuring creates new forms of the division of labor. On the basis of empirical data from a comparative project in 14 European countries, the author supports the hypothesis that in addition to the ongoing process of the internationalization of work, there are ‘hidden’ effects at the local level. From the perspective of three occupational clusters, dynamics can be observed which have differing impacts on the occupational groups. Thus, there is a simultaneous process of restructuring and redefining skills, labor processes and the working organization which forms the daily reality of working men and women.

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