Kinetics of methylene blue (MB) photocatalyzed reduction and dark regeneration in a colorimetric oxygen sensor

Performance data for a dye based, regenerable oxygen sensor (Mills and Lawrie [1], Mills et al. [2]) are analyzed to develop useful kinetic models for sensor photoactivation (dye reduction) and dark, oxygen detection (dye oxidation). The titania loaded, thin film sensor exhibits an apparent first order photoactivation of the dye, which we demonstrate (Section 3.2 and Fig. 4) is due to a kinetic disguise of a zero order photoreaction occurring through a non-uniformly illuminated sensor film. The observed zero order, slow recovery due to dye oxidation by dioxygen (O2 detection) appears best rationalized by a model assuming a near O2-impermeable skin developing on the sensor surface as solvent is evaporatively removed following sensor film casting and curing.

Back to the city: University-led Regeneration in Belfast

This paper explores the changing relationship between knowledge creation and city centre spaces, focusing on the relocation of Higher Education Institutions (HEIs) into urban centres and the ensuing economic, social and cultural regeneration. Using the Ulster University's relocation to Belfast city centre, the paper highlights the opportunities a new anchor institution can offer a deprived inner city community. This case study draws attention to the drivers of university relocation and the untapped potential for regeneration in city centres such as Belfast, Northern Ireland. The paper looks to the future and questions whether large-scale city projects, such as the university relocation, can truly form connections with their new neighbouring inner city communities while contending with the mounting pressure of reduced government resources.

Adaptive utilitarianism, social enterprises and urban regeneration

Social enterprises have been placed at the centre of Big Society politics and an emphasis on the local as a site for experimentation and service delivery. Nationally, this has been supported by legislation in community transfer and procurement, social finance and new intermediaries to strengthen skills and loan readiness. This paper examines the role of social enterprises involved in urban development in Northern Ireland and highlights the multiple ethics, legitimation strategies and modalities that are necessary for sustainable forms of progressive regeneration. The paper concludes by stressing the possibilities of a more independent and reformist social economy and how this offers some practical alternatives to the enthusiasm for neoliberal policies in the local state.

Housing, Regeneration and Community Asset Transfer

Community asset transfer enables local groups to own or manage a government owned facility and/or related services. For critics, it is merely an extension of roll-back neoliberalism, permitting the state to withdraw from welfare and transfer risk from local government to ill-defined communities. The paper uses quantitative and case study data from Northern Ireland to demonstrate its transformative potential by challenging the notion of private property rights, enabling communities to accumulate and endanger forms of cooperative consumption. It concludes by highlighting the implications for more progressive forms of social economics in relation to public and private markets and government sponsorship of its own development.

Post-fire vegetation regeneration in Portugal : implications for management

This thesis aims at improving the knowledge on the post-fire vegetation regeneration. For that, forests and shrublands were studied, after forest fires and experimental fires. Maritime Pine (Pinus pinaster) recruitment after fire was studied. Fire severity was evidenced as a major effect on this process. High crown fire severity can combust the pines, destroying the seed bank and impeding post fire pine recruitment. However, crown combustion also influences the post-fire conditions on the soil surface, since high crown combustion (HCC) will decrease the postfire needle cast. After low crown combustion (LCC) (scorched rather than torched crowns), a considerable needle cover was observed, along with a higher density of pine seedlings. The overall trends of post-fire recruitment among LCC and HCC areas could be significantly attributed to cover by needles, as well by the estimation of fire severity using the diameters of the burned twigs (TSI). Fire increased the germination from the soil seed bank of a Pinus pinaster forest, and the effects were also related with fire severity. The densities of seedlings of the dominant taxa (genus Erica and Calluna vulgaris) were contrastingly affected in relation to the unburned situation, depending on fire severity, as estimated from the degree of fire-induced crown damage (LCC/HCC), as well as using a severity index based on the diameters of remaining twigs (TSI). Low severity patches had an increase in germination density relatively to the control, while high severity patches suffered a reduction. After an experimental fire in a heathland dominated by Pterospartum tridentatum, Erica australis and E. umbellata, no net differences in seedling emergence were observed, in relation to the pre-fire situation. However, rather than having no effect, the heterogeneity of temperatures caused by fire promoted caused divergent effects over the burned plot in terms of Erica australis germination – a progressive increased was observed in the plots were maximum temperature recorded ranged from 29 to 42.5ºC and decreased in plots with maximum temperature ranging from 51.5 to 74.5ºC. In this heathland, the seed density of two of the main species (E. australis and E. umbellata) was higher under their canopies, but the same was not true for P. tridentatum. The understory regeneration in pine and eucalypt stands, 5 to 6 years post fire, has been strongly associated with post-fire management practices. The effect of forest type was, comparatively, insignificant. Soil tilling, tree harvesting and shrub clearance, were linked to lower soil cover percentages. However, while all these management operations negatively affected the cover of resprouters, seeders were not affected by soil tilling. A strong influence of biogeographic region was identified, suggesting that more vulnerable regions may suffer higher effects of management, even under comparatively lower management pressure than more productive regions. This emphasizes the need to adequate post-fire management techniques to the target regions.

Alkali-free bioactive glasses for bone regeneration

Bioactive glasses and glass-ceramics are a class of third generation biomaterials which elicit a special response on their surface when in contact with biological fluids, leading to strong bonding to living tissues. The purpose of the present study was to develop diopside based alkali-free bioactive glasses in order to achieve good sintering behaviour, high bioactivity, and a dissolution/ degradation rates compatible with the target applications in bone regeneration and tissue engineering. Another aim was to understand the structure-property relationships in the investigated bioactive glasses. In this quest, various glass compositions within the Diopside (CaMgSi2O6) – Fluorapatite (Ca5(PO4)3F) – Tricalcium phosphate (3CaO•P2O5) system have been investigated. All the glasses were prepared by melt-quenching technique and characterized by a wide array of complementary characterization techniques. The glass-ceramics were produced by sintering of glass powders compacts followed by a suitable heat treatment to promote the nucleation and crystallization phenomena. Furthermore, selected parent glass compositions were doped with several functional ions and an attempt to understand their effects on the glass structure, sintering ability and on the in vitro bio-degradation and biomineralization behaviours of the glasses was made. The effects of the same variables on the devitrification (nucleation and crystallization) behaviour of glasses to form bioactive glass-ceramics were also investigated. Some of the glasses exhibited high bio-mineralization rates, expressed by the formation of a surface hydroxyapatite layer within 1–12 h of immersion in a simulated body fluid (SBF) solution. All the glasses showed relatively lower degradation rates in comparison to that of 45S5 Bioglass®. Some of the glasses showed very good in vitro behaviour and the glasses co-doped with zinc and strontium showed an in vitro dose dependent behaviour. The as-designed bioactive glasses and glass–ceramic materials are excellent candidates for applications in bone regeneration and for the fabrication of scaffolds for tissue engineering.

Editorial: Cellulose dissolution and regeneration: systems and interactions

The interest in cellulose dissolution and regeneration is old but this topic has recently attracted strongly renewed attention. This is reflected in both applications- earlier and novel- and scientific controversies. This special issue attempts to connect a renewed fundamental understanding of molecular aspects with practical systems for dissolution and regeneration.

Dissecting the biophysical mechanisms underlying regeneration of complex organs in vertebrates

Tese de doutoramento, Ciências Biomédicas (Ciências Morfológicas), Universidade de Lisboa, Faculdade de Medicina, 2014

Reconsidering neoliberal urban planning intimes of crisis: urban regeneration policy in a "dense" space in Lisbon

In this article, I contribute to recent debates about the concept of neoliberalism and its use as an explanatory concept, through the analysis of urban planning and regeneration policy in Lisbon amidst crisis and austerity. Suggesting a look at neoliberalization from a threefold perspective—the project, governmentalities, and policymaking—I analyze how current austerity-policy responses to the European economic crisis can be understood as a renewed and coherent deployment of neoliberal stances. The article presents implications for urban planning in Lisbon and thus suggests an exploration of the negotiations and clashes of hegemonic neoliberal governmentalities and policies with the local social and spatial fabric. For this exploration, I select a “deviant” case—the Mouraria neighborhood, a “dense” space in which the consequences of policies diverge sharply from expectations. In conclusion, I suggest that neoliberalization (in times of crisis) should be understood as a coherent project compromised by a set of highly ambiguous governmentalities, which bring about contradictory policymaking at the local level.

Understanding community empowerment in urban regeneration and planning in England: putting policy and practice in context

Community involvement in the fields of town planning and urban regeneration includes a wide range of opportunities for residents and service users to engage with networks, partnerships and centres of power. Both the terminology and degree of the transfer of power to citizens varies in different policy areas and contexts but five core objectives can be identified. This article approaches the subject of community empowerment by exploring the theoretical literature; reviewing recent policy pronouncements relating to community involvement in England and by discussing a recent case study of an Urban II project in London. The conclusions suggest that community empowerment is always likely to be partial and contingent on local circumstances and the wider context.