Ferritins are ubiquitous and can be found in practically all organisms that utilize Fe. They are composed of 24 subunits forming a hollow sphere with an inner cavity of similar to 80 angstrom in diameter. The main function of ferritin is to oxidize the cytotoxic Fe2+ ions and store the oxidized Fe in the inner cavity. It has been established that the initial step of rapid oxidation of Fe2+ (ferroxidation) by H-type ferritins, found in vertebrates, occurs at a diiron binding center, termed the ferroxidase center. In bacterial ferritins, however, X-ray crystallographic evidence and amino acid sequence analysis revealed a trinuclear Fe binding center comprising a binuclear Fe binding center (sites A and B), homologous to the ferroxidase center of H-type ferritin, and an adjacent mononuclear Fe binding site (site C). In an effort to obtain further evidence supporting the presence of a trinuclear Fe binding center in bacterial ferritins and to gain information on the states of the iron bound to the trinuclear center, bacterial ferritin from Desulfovibrio vulgaris (DvFtn) and its E130A variant was loaded with substoichiometric amounts of Fe2+, and the products were characterized by Mossbauer and EPR spectroscopy. Four distinct Fe species were identified: a paramagnetic diferrous species, a diamagnetic diferrous species, a mixed valence Fe2+Fe3+ species, and a mononuclear Fe2+ species. The latter three species were detected in the wild-type DvFtn, while the paramagnetic diferrous species was detected in the E130A variant. These observations can be rationally explained by the presence of a trinuclear Fe binding center, and the four Fe species can be properly assigned to the three Fe binding sites. Further, our spectroscopic data suggest that (1) the fully occupied trinuclear center supports an all ferrous state, (2) sites B and C are bridged by a mu-OH group forming a diiron subcenter within the trinuclear center, and (3) this subcenter can afford both a mixed valence Fe2+Fe3+ state and a diferrous state. Mechanistic insights provided by these new findings are discussed and a minimal mechanistic scheme involving O-O bond cleavage is proposed.

Native agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars’ structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-D-galactose (G) and 3,6-anhydro-α-L-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAEopt agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and Mv obtained for the MAEopt sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.

This work reports a novel strategy to prepare affinity composite membranes using supercritical fluid technology. By blending molecularly imprinted polymeric particles with PMMA, a porous hybrid structure with affinity to the template molecule, bisphenol A, was prepared using a supercritical carbon dioxide (scCO2)-assisted method. Membranes were characterized in terms of morphology, mechanical performance and transport properties. The ability of the polymers and hybrid membranes to adsorb bisphenol A was tested in aqueous solutions and fitted to a linearized Langmuir equation, showing that adsorption takes place at homogeneous affinity binding sites within the imprinted surface. Filtration experiments showed that the imprinted hybrid membrane was able to adsorb higher amounts of template even in non-equilibrium dynamic binding conditions. The hybridization of the \{PMMA\} membrane herein reported conveys two important improvements over neat \{PMMA\} membrane: it introduced molecular affinity towards the template molecule and significantly increased the permeability of the porous structures, which are key parameters in processes that involve membranes. This technique could expand the applications of polymeric beads powders and enhance the efficiency of the membrane's transport properties. Our work presents a new method to confer affinity to a porous structure by immobilization of imprinted polymers, combining polymer synthesis and membrane formation using supercritical fluid technology.

Molecularly imprinted polymeric particles with molecular recognition towards Bisphenol A (BPA) were synthesized for the first time using the semi-covalent imprinting approach in supercritical carbon dioxide (scCO2). The material{'}s affinity to BPA was achieved by co-polymerizing ethylene glycol dimethacrylate (EGDMA) with a template-containing monomer{,} Bisphenol A dimethacrylate (BPADM) in scCO2. Bisphenol A is then cleaved from the polymeric matrix by hydrolysis with tetrabutylammonium hydroxide (n-Bu4OH) also in a supercritical environment{,} taking advantage of the high diffusivity of scCO2. The selectivity of the molecular imprinted polymer (MIP) was assessed by evaluating its capability to bind BPA in comparison with progesterone and [small alpha]-ethinylestradiol. In addition{,} the cross-linked particles were used to prepare a PMMA-based hybrid imprinted membrane by a scCO2-assisted phase inversion method. Results show that the incorporation of MIP particles was able to confer molecular affinity to BPA to the membrane and that at dynamic conditions of filtration{,} this imprinted porous structure was able to adsorb a higher amount of BPA than the corresponding non-imprinted hybrid membrane. Our work represents a valuable greener alternative to conventional methods{,} for the synthesis of affinity materials which are able to maintain molecular recognition properties in water.

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The properties of the light flexible device, ion jelly, which combines gelatin with an ionic liquid (IL) were recently reported being promising to develop safe and highly conductive electrolytes. This article aims for the understanding of the ion jelly conductive mechanism using dielectric relaxation spectroscopy (DRS) in the frequency range 10-1-106 Hz; the study was complemented with differential scanning calorimetry (DSC) and pulse field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. The room temperature ionic liquid 1-butyl-3-methylimmidazolium dicyanamide (BMIMDCA) used as received (1.9% w/w water content) and with 6.6% (w/w) of water content and two ion jellies with two different ratios BMIMDCA/gelatin/water % (w/w), IJ1 (41.1/46.7/12.2) and IJ3 (67.8/25.6/6.6), have been characterized. A glass transition was detected by DSC for all materials allowing for classifying them as glass formers. For the ionic liquid, it was observed that the glass transition temperature decreases with the increase of water content. While in subsequent calorimetric runs crystallization was observed for BMIMDCA with negligible water content, no crystallization was detected for any of the ion jelly materials upon themal cycling. To the dielectric spectra of all tested materials, both dipolar relaxation and conductivity contribute; at the lowest frequencies, electrode and interfacial polarization highly dominate. Conductivity, which manifests much more intensity relative to dipolar reorientations, strongly evidences subdiffusive ion dynamics at high frequencies. From dielectric measures, transport properties as mobility and diffusion coefficients were extracted. Data treatment was carried out in order to deconvolute the average diffusion coefficients estimated from dielectric data in its individual contributions of cations (D+) and anions (D-). The D+ values thus obtained for IJ3, the ion jelly with the highest IL/gelatin ratio, cover a large temperature range up to room temperature and revealed excellent agreement with direct measurements from PFG NMR, obeying to the same VFT equation. For BMIMDCA6.6%water, which has the same water amount as IJ3, the diffusion coefficients were only estimated from DRS measurements over a limited temperature range; however, a single VFT equation describes both DRS and PFG NMR data. Moreover, it was found that the diffusion coefficients and mobility are similar for the ionic liquid and IJ3, which points to a role of both water and gelatin weakening the contact ion pair, facilitating the translational motion of ions and promoting its dissociation; nevertheless, it is conceivable that a critical composition of gelatin that leads to those properties. The VFT temperature dependence observed for the conductivity was found to be determined by a similar dependence of the mobility. Both conductivity and segmental motion revealed to be correlated as inferred by the relatively low values of the decoupling indexes. The obtained results show that ion jelly could be in fact a very promising material to design novel electrolytes for different electrochemical devices, having a performance close to the IL but presenting an additional stability regarding electrical measurements and resistance against crystallization relative to the bulk ionic liquid.

Technology assessment is essentially a systematic method used to investigate technology developments and assess their potential impacts on society. The assessment of emerging technologies, however, requires special attention. To address technologies at early stages of development, Constructive Technology Assessment (CTA) is considered to be one of the best options to bypass the Collingridge dilemma - which fundamentally states that controlling the direction of a technology’s development is very hard. Technologies at early stages of development might appear to be unorganized, chaotic and with high level of uncertainty on future paths to take. Future Oriented Technology Analysis (FTA) represents any systematic process to produce judgments about the characteristics of emerging technologies, its development pathways, and potential future impacts. Technology Assessment is considered to be one of three subjects which form the umbrella concept of FTA. The technology assessed on this project, Brain-Computer Interface (BCI) or Brain-Machine Interface (BMI) is an emerging technology. BCIs can be defined as a technology which allows for the direct communication between the brain and an external device. It is a truly direct connection, with no use of the normal output pathways of peripheral nerves and muscles, allowing for the brain to have control over objects and softwares without intermediates. As an emerging technology, BCI is at its early stages of research and thus many challenges are still ahead. Mainstream adoption is not expected in least 10 years. There are still many problems and challenges to be overcome. The real impacts of BCI will depend directly on the development of competing technologies. If there is improvement in BCI research, then the potential applications and end users could grow dramatically. The findings of this project will be of relevant importance to researchers of the technology (especially on what concerns their interactions with other stakeholders

In the last decades, with the consequent strong competitiveness of an increasingly globalized world, the foresight studies have gained importance in the business environment and also became important tool for formulation of public policy. This work examines the recent foresight studies from Brazil, Finland and Japan, to understand the main goals, motivations and methodologies used. And finally drawing lessons from international cooperation in foresight studies that might be interesting for the Brazilian case. It can be concluded it is extremely useful to look at the studies conducted by countries with more experience in the foresight as a way to deepen and develop methods analysis. The work conducted by Japan and Finland showed that is possible succeed through studies in cooperation, even with the different features of the national reality.

This paper aims to present the main events over the years on public policies for financing R & D in Portugal, with special focus on the QREN (National Strategic Reference Framework). Between 2007 and 2013, is the QREN which provides the framework to be applied to economic policy in Portugal. The Incentives System for Companies Investment is one of the key instruments of economic promotion policies, particularly in terms of promoting innovation and regional development. The review made shows us that there is not still a systemic and integrated policy innovation in Portugal, but there is a set of instruments that can play a role in this policy and also has missed coherence and coordination between them.

This report is the result of the presentation of the Thesis Plan, performed on December 13, 2011, during the activities of the Winter School of Doctoral Program in Technology Assessment. It is intended to describe the main information about the Thesis Plan and also the definition of the main concepts involved. Can also view the presentation file that is available on the page of the student's PhD thesis Ana Cândido in Moodle (http://moodle.fct.unl.pt/mod/resource/view.php?inpopup=true&id=157805). The following step in this report will be the development of the discipline of “Project IV” and so also the preparation for Doctoral Conference will take place in June 2012.

In this paper we reflect upon how policy-makers look for, interpret and use evidence for reflection and policy development. We propose an exploratory framework that sets out two of the elements necessary to a conceptualization of what may explain the way in which evidence and indicators are used in STI policy development: the type of evaluative approach and the styles of governance.

SORs (superoxide reductases) are enzymes involved in bacterial resistance to reactive oxygen species, catalysing the reduction of superoxide anions to hydrogen peroxide. So far three structural classes have been identified. Class I enzymes have two iron-centre-containing domains. Most studies have focused on the catalytic iron site (centre II), yet the role of centre I is poorly understood. The possible roles of this iron site were approached by an integrated study using both classical and fast kinetic measurements, as well as direct electrochemistry. A new heterometallic form of the protein with a zinc-substituted centre I, maintaining the iron active-site centre II, was obtained, resulting in a stable derivative useful for comparison with the native all-iron from. Second-order rate constants for the electron transfer between reduced rubredoxin and the different SOR forms were determined to be 2.8 x 10 M(1) . s(1) and 1.3 x 10 M(1) . s(1) for SORFe(IIII)-Fe(II) and for SORFe(IIII)-Fe(III) forms respectively, and 3.2 x 10 M(1) . s(1) for the SORZn(II)-Fe(III) form. The results obtained seem to indicate that centre I transfers electrons from the putative physiological donor rubredoxin to the catalytic active iron site (intramolecular process). In addition, electrochemical results show that conformational changes are associated with the redox state of centre I, which may enable a faster catalytic response towards superoxide anion. The apparent rate constants calculated for the SOR-mediated electron transfer also support this observation.

Sistema para detección, identificación y cuantificación en material biológico, compuesto por una o más fuentes de luz (1) combinado con uno o más fotosensores ópticos (6 y 7) y diversos componentes electrónicos (4), necesarios para obtener/procesar la señal emitida caracterizado por: a) La fuente de luz (1), pulsada (2) o no, compuesta de láseres de estado sólido de baja energía o diodos emisores de luz, cuyo rango de longitud de onda está localizado entre 400 y 800 nm con una intensidad de luminosidad controlable que varía entre los valores de 0.01 mW/cm 2 y 100 mW/cm 2 ; b) El fotosensor, sencillo (6 y 7a) y (6 y 7b) o integrado (6, 4 y 7) compuesto de películas delgadas de silicio amorfo o nanocristalino o microcristalino y/o por semiconductores de cerámica tales como IGZO, IAgZO, SnZIO, GZIO, CuOIZ, GITO, entre otros, y basado en estructuras tipo pi'ii'n o MIS, que funciona en un rango de longitudes de onda desde el infrarrojo hasta el ultravioleta, y prové una información cualitativa y cuantitativa basada en la hibridización especifica y selectiva de sondas funcionalizadas con nanopartículas de metal; c) Siendo provista la eliminación del sistema a través de una fuente de energía convencional o a través de baterías fotovoltaicas, que dan portabilidad al sistema, siendo focalizada la luz emitida sobre la muestra, preferiblemente utilizando microlentes, siendo la muestra o muestras no fijadas físicamente al sensor o sensores, colocando la muestra biológica referida (5) sobre el lado opuesto (6) del sustrato donde se deposita el fotosensor (6 y 7).

No abstract is available for this item.