Experimental Research with Salt Crystallization in Historical Portuguese Azulejos

The most serious form of degradation of historical azulejos is the spall of the glaze and it is widely accepted that the crystallization of salts dissolved in water circulating in the masonry is its main cause. This article reports the results of an accelerated aging test aimed at studying the physical deterioration of azulejos caused by cycles of dissolution and re-crystallization of sodium chloride (NaCl). Experiments were carried out on 26 Portuguese azulejos from the 17th–19th century, some of which with original manufacturing defects or with varying degrees of previous decay.

The results of 75 cycles over 18 months did not verify that the action of NaCl could trigger an accelerated loss of glaze in a healthy azulejo. Furthermore, the results lead to the induction that there must be other, eventually concurring, causes for the spall of glaze than a simple challenge with salts that crystallize by evaporation.     

The spatial dimension of internal labor markets

We integrate into a unified framework the spatial and the employment dimensions of worker mobility, tracing workers across firms, across establishments, and across regions. Drawing upon the spatial dimension of internal labor markets in firms with multiple establishments in multiple locations, our results indicate that the contemporaneous wage premium to migration is around 3 percentage points. For the case of job switchers, we find that the return to regional migration is due to access to better jobs at the destination. We also document the existence of an urban premium for same‐employer migrants but for employer changes this premium is driven by selection.     

Mapping cultural policy in Portugal: From incentives to crisis

Abstract

Taking into account the course of cultural policy in democratic Portugal, and against the backdrop of the international crisis of 2008 and the sovereign debt crisis of 2011, this article seeks to interpret recent changes in the cultural sector in Portugal. Using both qualitative and quantitative methods it focuses on three main aspects: institutionalisation of democratic cultural policy; government funding; cultural organizations and facilities. The 2008 crisis put an end to a period in which investment tended to grow. We place Portugal in the broader European context, concluding that the Portuguese cultural scene may once again diverge from that of other European countries.     

Performing postcolonial identities at the United Nations’ climate negotiations

This study aims to understand how postcolonial identities were performed in the negotiations that led to the new climate agreement signed in Paris in December 2015. Based on interviews, the analysis of documents and participant observation of the negotiations it was possible to identify the legal, economic and scientific discourses mobilised by both global North and South countries. In all three discourses, it was possible to identify a systematic effort of the Northern parties to unmake the identity of Southern parties as ‘developing countries’ as a way to erase the ontological difference between emerging and established industrialised economies. At the same time, in the context of the convention Southern parties reaffirmed their identities as ‘developing countries’ and demanded from the North a strong commitment to tackle climate change and the transfer of more financial resources to the South. In this process, it was also possible to identify an inversion of the position usually taken by mainstream and critical postcolonial scholars that see the deconstruction of categories such as ‘developing countries’ as key for the emancipation of the global South. Finally, this invites postocolonial scholars to look more closely at how postcolonial identities are being instrumentalised, discursively and politically.     

A sweet and amnesic present: the postcolonial landscape and memory makings in Cape Verde

The construction of memory in landscapes is a complex process which is embedded in webs of political and economic power. Often history is twisted and bended to better serve the current interests of the hegemonic forces at play. In this paper I attempt to explore how memory is at work in three different sites in Santiago Island, Cape Verde: an old fort and a historical town; a concentration camp; and a global resort. The three sites participate in the erasure, maintenance and creation of memory in different ways, forging new forms of collective identity, which are embedded in local as well as global forces and processes. Through an analysis of the changes taking place on these sites, this paper suggests that while the country lives on foreign aid and attempts to embrace neo-liberal practices, it fails not only to provide basic services to the population but to engage critically with its history and geography.     

A review of archaeological research on sami prehistory

Abstract

The English botanist and gardener John Tradescant the Elder's diary from a voyage to northern Russia in 1618 has lately attracted attention as a potential source on early Russian sea mammal hunting on the Svalbard archipelago. This article examines the usefulness of Tradescant's diary in this respect, but comes to a negative conclusion.     

Seismic Tests and Numerical Modeling of a Rolling-ball Isolation System

For the seismic isolation of light structures, the use of laminated rubber bearings is neither economical nor, for most cases, technically suited. For the isolation of this type of structure a new system, consisting of steel balls rolling on rubber tracks, has been developed at TARRC (Tun Abdul Razak Research Centre).

This article presents the results of experimental tests carried out for the characterization of the behavior of this new device. A numerical model is also proposed that can be used to assess the seismic response of structures with this isolation system.

Comparison of the predictions of the numerical model with the experimental data shows that the model is adequate to perform the correct assessment of the seismic response of isolated structures. The results of the experimental campaign of shaking-table tests, as well as the numerical simulations, show that there is an effective reduction of the acceleration levels induced in the isolated structures.     

Statistical Characterization of Structural Demand under Earthquake Loading. Part 1: Robust Estimation of the Central Value of the Data

This article is the first of two companion articles addressing the statistical characterization of seismic demand. Performance-based earthquake engineering methodologies often require the characterization of central value estimates of structural demand. Since outliers can occur in the data, central value estimates should be determined by robust estimation methods. The performance of 50 robust central value estimators is evaluated, for different sample sizes, using the chord rotation, curvature, shear force, and inter-story drift demands obtained after analyzing five reinforced concrete structures under real earthquake records scaled to several intensities. Based on the results, seven estimators are proposed for different sample sizes.