What makes people stay in or leave shrinking cities? An empirical study from Portugal

The attractiveness of cities as places to live determines population movements into or out of them. Understanding the appealing features is fundamental to local governments, particularly for cities facing population decline. Pull and push attributes can include economic aspects, the availability of amenities and psychological constructs, initiating a discussion around which factors are more relevant for migration. However, such discussion has been underexplored in studies of shrinking cities. In the present study, we contribute to the discussion by identifying pull and push factors in Portuguese shrinking cities. Data were collected using a face-to-face questionnaire of 701 residents in four shrinking cities: Oporto, Barreiro, Peso da Régua and Moura. Factor analysis and automatic linear modelling were used to analyse the data. Our results show that the economic activity is the most relevant feature for retaining residents. However, characteristics specific to each city, related to heritage and natural beauty, are also shown to influence a city’s attractiveness. The cause of population shrinkage was also found to influence residents’ assessments of the pull and push attributes of each city. Furthermore, the results show the relevance of social ties and of place attachment to inhabitants’ intention to continue living in their city of residence.     

Mapping the Stone Age of Mozambique

Under the auspices of the Portuguese colonial government, Lereno Barradas and Santos Júnior (coordinator of the Anthropological Mission of Mozambique) carried out several archaeological field surveys from 1936 to 1956 that resulted in a data set that includes a total of close to 90 sites, mostly attributed to the Stone Age. This early research added to the previous work of Van Riet Lowe in the Limpopo Valley of southern Mozambique. With the new millennium, Mozambique has emerged as a crucial geographic area in which to understand the various hypotheses about recent human evolution. Specifically, its coastal location between southern and eastern Africa is ideal for testing ideas about the link between early coastal adaptations and the appearance of anatomically modern humans (AMH). Except for the recent work by Mercader’s team in northern Mozambique, the number of researchers and projects on this topic in Mozambique is still limited because of the general predominance of interest in later periods among archaeologists working in the country, mainly due to their focus on issues related to precolonial heritage and national identity. Based on the early maps from Santos Júnior and more recent data acquired through various projects, we present a series of maps for the Stone Age prehistory of Mozambique. The maps are also based on a critical evaluation of the sites and a review of some of the materials that are presently curated at the Instituto de Investigação Científica e Tropical (IICT) in Lisbon, Portugal, as well as the materials stored at the Department of Archaeology of Universidade Eduardo Mondlane, Maputo. The sites are also presented in an online database with the information on all sites used in this study. This database is open to all and will be updated continuously. A preliminary interpretation of the regional distribution of the sites is also attempted, linking aspects that include region, topography and altitude, geomorphology, and cultural phase. These results will be the first step for research and knowledge in Mozambique on Stone Age prehistory and the emergence and settlement pattern of AMH.     

Statistical Characterization of Structural Demand under Earthquake Loading. Part 2: Robust Estimation of the Dispersion of the Data

Performance-based earthquake engineering methodologies often require a probabilistic model of structural demand. Since observations masking the probability distribution of the majority of the data are frequently found, robust estimation methods are proposed to estimate the probabilistic model parameters (i.e., central value and dispersion). The performance of thirty-three robust dispersion 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, combinations involving dispersion and central value (defined in a companion article) estimators are proposed.     

Permian non-marine bivalves of the Falkland Islands and their palaeoenvironmental significance

Simões, M.G., Quaglio, F., Warren, L., Anelli, L.E., Stone, P., Riccomini, C., Grohmann, C.H. & Chamani, M.A.C. December 2012. Permian non-marine bivalves of the Falkland Islands and their palaeoenvironmental significance. Alcheringa 36, 543–554. ISSN 0311-5518.

We describe the occurrence of non-marine bivalves in exposures of the Middle Permian (Capitanian) Brenton Loch Formation on the southern shore of Choiseul Sound, East Falklands. The bivalves are associated with ichnofossils and were collected from a bed in the upper part of the formation, within a 25 cm thick interval of dark siltstones and mudstones with planar lamination, overlain by massive sandstones. The shells are articulated, with the valves either splayed open or closed. At the top of the succession, mudstone beds nearly 1.5 m above the bivalve-bearing layers yielded well-preserved Glossopteris sp. cf. G. communis leaf fossils. The closed articulated condition of some shells indicates preservation under high sedimentation rates with low residence time of bioclasts at the sediment/water interface. However, the presence of specimens with splayed shells is usually correlated to the slow decay of the shell ligament in oxygen-deficient bottom waters. The presence of complete carbonized leaves of Glossopteris associated with the bivalve-bearing levels also suggests a possibly dysoxic-anoxic bottom environment. Overall, our data suggest that the bivalves were preserved by abrupt burial, possibly by distal sediment flows into a Brenton Loch lake, and may represent autochthonous to parautochthonous fossil accumulations. The shells resemble those of anthracosiids and are herein assigned to Palaeanodonta sp. aff. P. dubia, a species also found in the Permian succession of the Karoo Basin, South Africa. Our results confirm that (a) the true distributions in space and time of all Permian non-marine (freshwater) bivalves are not yet well known, and (b) there is no evidence for marine conditions in the upper part of the Brenton Loch Formation.     

Saul and Cultural Memory

ABSTRACT

In recent years a number of biblical scholars have shown that the Hebrew Bible contains both the collective memory and amnesia of ancient Israel. The differences between the portrayals of Saul in the books of Samuel and 1 Chronicles have long been explained in terms of redaction history, inner-biblical exegesis and other intertextual reading strategies. Using the insights from the fields of sociology and psychology cultural memory theory suggests that it was the dynamics of structural amnesia that made it necessary to suppress the memories of Saul that were not useful to the reconstruction of the past, and that the new “master narrative” in the Book of Chronicles may be seen as a post-trauma solution to the Israelites’ painful retrieval of memories of guilt and trauma.     

Fregatten Mynden: a 17th-century Danish Frigate Found in Northern Germany

The remains of a small 17th-century Danish frigate were investigated off the island of Rügen in Mecklenburg-Vorpommern, northern Germany. Through research in the Danish National Archives in Copenhagen it was possible to identify the ship. Using documentary and archaeological sources, the layout, equipment and appearance of one of the small and less prestigious warships of the 17th and early 18th century could be reconstructed. In addition, aspects of shipboard life will be illustrated.
© 2004 The Nautical Archaeology Society     

Soluble Salts Amplify the Effect of Small Heterogeneities in the Structure of Porous Building Materials During Drying

Salt crystallization is a major cause of degradation in old buildings. One of the issues that stills need clarification is regarding the influence of the salts on the capillary absorption and subsequent drying of porous building materials. This article presents an experimental study that included capillary absorption and evaporative drying tests on two types of material (lime mortar and ceramic brick) using pure water or saturated solutions of six salts (sodium chloride, sodium sulfate, sodium nitrate, sodium carbonate, potassium nitrate, or potassium carbonate). The results of capillary absorption agree only roughly with the linear relationship, predicted by theory, between sorptivity and the square root of the ratio between viscosity η and surface tension σ of the solution (σ/η)^1/2. This poor agreement is probably due to material heterogeneity. The drying dynamics was regular and showed little dispersion between specimens, but only for the uncontaminated materials. Indeed, the drying dynamics of the salt contaminated materials was often irregular or diverged among similar specimens, and the same happened with their salt decay patterns. The main conclusion is that soluble salts can amplify the effects on drying of the small structural heterogeneities that porous building materials normally depict.