Ortigueira, MD.
2007.
Riesz Potentials as Centred Derivatives. Advances in Fractional Calculus. :93-112., Springer Netherlands
AbstractGeneralised fractional centred differences and derivatives are studied in this Chapter. These generalise to real orders the existing ones valid for even and odd positive integer orders. For each one, suitable integral formulations are presented. The limit computation inside the integrals leads to generalisations of the Cauchy derivative. Their computations using a special path lead to the well known Riesz potentials. A study for coherence is done by applying the definitions to functions with Fourier transform. The existence of inverse Riesz potentials is also studied.
Todorovic, S, Leal SS, Salgueiro CA, Zebger I, Hildebrandt P, Murgida DH, Gomes CM.
2007.
A Spectroscopic Study of the Temperature Induced Modifications on Ferredoxin Folding and Iron−Sulfur Moieties. Biochemistry. 46(37):10733-10738.
AbstractThermal perturbation of the dicluster ferredoxin from Acidianus ambivalens was investigated employing a toolbox of spectroscopic methods. FTIR and visible CD were used for assessing changes of the secondary structure and coarse alterations of the [3Fe4S] and [4Fe4S] cluster moieties, respectively. Fine details of the disassembly of the metal centers were revealed by paramagnetic NMR and resonance Raman spectroscopy. Overall, thermally induced unfolding of AaFd is initiated with the loss of α-helical content at relatively low temperatures (Tapp (m) ~ 44 °C), followed by the disruption of both iron−sulfur clusters (Tapp (m) ~ 53−60 °C). The degradation of the metal centers triggers major structural changes on the protein matrix, including the loss of tertiary contacts (Tapp (m) ~ 58 °C) and a change, rather than a significant net loss, of secondary structure (Tapp (m) ~ 60 °C). This latter process triggers a secondary structure reorganization that is consistent with the formation of a molten globule state. The combined spectroscopic approach here reported illustrates how changes in the metalloprotein organization are intertwined with disassembly of the iron−sulfur centers, denoting the conformational interplay of the protein backbone with cofactors.
Moniz, A.
2007.
The Collaborative Work Concept and the Information Systems Support: Perspectives for and from Manufacturing Industry. , Number 5627: University Library of Munich, Germany
AbstractMost of the discussion and controversy on organisation of work concepts has been referenced to the manufacturing industry along the 20th century: it started with the concept of “scientific management” from Taylor, and continued with the new ideas on the importance of human factors as Mayo pointed out in the 1930s. Immediately after the 2nd World War Friedmann studied the human problems related to new manufacturing technologies and automation. And the late 1950 and 1960s were decades of strong debate on the socio-technics with the research at Tavistock Institute of London and the emergence of national programmes on new forms of work organisation. At the end of the last century the concept of collaborative work was developed together with the definition(s) of information systems and organisational design. However, the interest came from other production activities, like the services. This article analyses the approaches developed on these debates on the collaborative work and information system and its application to the manufacturing industry.
Ferreira, IMPLVO, Eca R, Pinho O, Tavares P, Pereira A, Roque AC.
2007.
Development and validation of an HPLC/UV method for quantification of bioactive peptides in fermented milks. JOURNAL OF LIQUID CHROMATOGRAPHY \& RELATED TECHNOLOGIES. {30}:{2139-2147}., Number {13-16}
AbstractThe simultaneous separation and quantification of two casein peptides (IPP, VPP) presenting potent inhibitory activity of angiotensin-converting-enzyme (ACE) and casein in fermented milks was developed. Gradient elution was carried out at a flow-rate of 1 mL/min, using a mixture of two solvents. Solvent A was 0.1% TFA in water and solvent B was acetonitrile-water-trifluoracetic acid 95:5:0.1. The effluent was monitored by UV detector at 214 nm. Calibration curves were constructed in the interval of 0.01-1.0 mg/mL for VPP, 0.005-1.0 mg/mL for IPP, and 0.05-3.0 mg/mL for casein. R 2 invariably exceeded 0.999. The detection limits were 0.004 for VPP, 0.002 mg/mL for IPP, and 0.02 mg/mL for casein. Repeatability of the method was evaluated by six consecutive injections of two standard solutions containing VPP, IPP, and casein. The RSD values for concentration were all below 5.08%. Recovery studies were carried out to determine the accuracy of the method. Recoveries ranged between 88 and 98.2%. The methodology was applied, not only, for the monitorization of VPP, IPP, and casein in commercial fermented milks labeled as presenting anti hypertensive properties, but also, in milk with different degrees of fermentation by L Helveticus, and in other commercial functional fermented milks, such as, those presenting cholesterol lowering properties.
Carvalho, AL, Dias FMV, Nagy T, Prates JAM, Proctor MR, Smith N, Bayer EA, Davies GJ, Ferreira LMA, Romao MJ, Fontes CMGA, Gilbert HJ.
2007.
Evidence for a dual binding mode of dockerin modules to cohesins. Proceedings of the National Academy of Sciences of the United States of America. 104:3089-3094., Number 9
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Coelho, C, Gonzalez PJ, Trincao J, Carvalho AL, Najmudin S, Hettman T, Dieckman S, Moura JJG, Moura I, Romao MJ.
2007.
Heterodimeric nitrate reductase (NapAB) from Cupriavidus necator H16: purification, crystallization and preliminary X-ray analysis. Acta Crystallographica Section F-Structural Biology and Crystallization Communications. 63:516-519.
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Fv, V, Violante S, Gomes C, Carvalho AL, Romao MJ, Gaspar MM, Cruz MEM, Soveral G, Wanders RJ, Leandro P, de Almeida TV.
2007.
The human carnitine acylcarnitine translocase (hCACT): Strategies for its heterologous expression, purification and crystallization. Journal of Inherited Metabolic Disease. 30:53-53.
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Ricardo, CNE, Ortigueira MD, Gerald JAB.
2007.
New quasi-orthogonal BCH-derived sequences for CDMA applications. European Transactions on Telecommunications. 18:803–810., Number 7: John Wiley & Sons, Ltd.
AbstractBased on two methods recently proposed - the Ranging Criterion (RC) and the Generators Ranging Criterion (GRC) - new (quasi-orthogonal) even BCH-derived sequences are generated which are very attractive for synchronous or quasi-synchronous Code Division Multiple-Access (CDMA) systems. Numerical results show that the new family of BCH-derived sequences can contain a higher number of quasi-orthogonal sequences with lower correlation values and higher processing gains (PGs) than the spreading sequences typically used in the third generation of mobile communications system, UMTS or in the recent large area synchronised CDMA (LAS-CDMA) technology. It is shown that the even BCH-derived sequences are easily generated by a linear shift register generator, allowing the construction of systems with receiver structures of low complexity as compared with those of quasi-synchronous systems using low correlation zone sequences, as for instance the LAS-CDMA system.