The role of arsenic in Chalcolithic copper artefacts – insights from Vila Nova de São Pedro (Portugal)

The Castro of Vila Nova de São Pedro (VNSP) is an emblematic settlement located at Azambuja, Portuguese Estremadura. It was occupied during the third and second millennia BC, predominantly during the Chalcolithic period. A diversified collection of 53 copper-based artefacts (most part in a fragmentary condition), belonging to an extensive metallic collection recovered during excavations carried out in VNSP, was studied using micro-EDXRF spectrometry, optical microscopy and SEM-EDS. Additionally, Vickers microhardness measurements were performed to establish the effectiveness of the thermomechanical treatment in the hardness of the artefacts. Results show that the Largo do Carmo, artefact collection is mainly composed of copper or arsenical copper, being 37% of the artefacts made of copper alloyed with arsenic (As > 2%). A statistically significant association was found between copper alloyed with arsenic and artefacts classified as tools/weapons (arrowheads, daggers and knives). In several cases, the presence of arsenic rich phases in the microstructure, resulting from an inverse segregation phenomenon, shows no evidence of chemical homogeneity control during the artefact manufacture. Microstructural analyses also show that the majority of this group (73%) was shaped with forging plus annealing operation cycles and 23% of the artefacts received a final cold hammering after the forging and annealing. An association between the presence of a final forging treatment and artefacts presenting higher arsenic contents was also identified. Nevertheless, no direct correlation was found between the arsenic content of the alloy and its hardness. Also no direct correlation was found between the hardness and a final forging operation. However, it was observed that a harder forging was applied to the cutting edge of the artefacts and consequently a high hardness in this area was obtained despite the arsenic content of the alloy. Concerning arsenical copper alloys, all evidences point out that the potential for obtaining a harder material was not recognized by the ancient metallurgists and the selection of the alloy was possibly made based on colour.     

Latest developments in rock art recording: towards an integral documentation of Levantine rock art sites combining 2D and 3D recording techniques

This paper presents a further step in the integral documentation of prehistoric rock art, combining 2D and 3D digital recording techniques. Image processing and digital enhancement techniques are an invaluable aid to obtain high quality and accurate 2D recordings, especially when working with faint motifs or complex superimpositions. But what constitutes a real breakthrough is the possibility of combining 2D digital tracings with metric 3D models, providing a whole set of metric outputs that improve our understanding of the motifs in their context and, at the same time, can be used to deliver accurate metric reproductions.     

The Henequen Ports of Yucatan’s Gilded Age

Over the last two centuries, the coast has played a major role in the economy of Yucatán, and has served as a key venue in its growing engagement in the global economy. A prominent chapter in this history took place during the Gilded Age (1860–1915), which saw the emergence of a powerful plantation class whose wealth was based on meeting international demand for the fiber of the agave, or henequen plant, which was used to manufacture rope, cordage, and twine. The cultivation of this plant gave rise to hundreds of plantations, and an accompanying infrastructure of haciendas, fiber processing plants, and an extensive regional network of railways for transporting henequen to the port of Progreso, from whence it was exported to North America and Europe. As part of this infrastructure, several plantation owners laid rail lines from their haciendas to the coast and built small ports for shipping their henequen to Progreso. These ports, which are documented in these pages, represented a substantial capital outlay, and were built under the shadow of the gathering clouds of the Mexican Revolution. Viewed in retrospect, they offer an insightful perspective on the economic outlook of the Yucatecan elites in the dawn of the modern age.     

Multinational Knowledge Strategies,Policy and the Upgrading Process of Regions: Revisiting the Automotive Industry in Ostrava and Shanghai

This paper revisits how and why new multinational knowledge-based strategies and multi-level governmental policies influence the upgrading process of regions in developing economies. Automotive multinationals traditionally exploited local asset conditions, but it is shown that they have also been contributing to knowledge-generation systems via investments in R&D centres and cooperation with regional knowledge producers. We discern three elements of the upgrading process of regions—upgrading of domestic firms, subsidiary evolution and establishment of strategic relations with local knowledge institutes—to analyse two case studies: Ostrava (Czech Republic) and Shanghai (China). The cases show that all types of upgrading—product, process, chain and functional—have taken place in the last years, and that follow sourcing may have a positive impact on regional upgrading. These observations provide lessons for governments in developing economies which aim to strengthen innovation-based regional development.     

An experimental approach to the study of interpersonal violence in Northeastern Patagonia (Argentina), during the late Holocene

This paper incorporates an experimental approach to the study of violence patterns in Northeastern Patagonia (Argentina) during the late Holocene. The underlying hypothesis considers a close association between socio-ecologic alterations during the Medieval Climatic Anomaly (MCA) (ca. 1150-600 years BP; Stine, 1994, 2000) and a probable increase in conflict levels. In order to test this hypothesis, human skulls (n = 986) were analyzed for bone lesions, discriminating late bone lesions, such as those produced by metal tools. The experimental approach used swine (Sus scrofa domestica) skulls, as proxies for human skulls, and incorporated original sabers. From this discriminating analysis, it can be inferred that no significant increase in violence signs were recorded until the first stages of Hispanic-indigenous contact (first half of 17th century). These findings emphasize the need for a revision of the implications of the dynamics of human populations in Northeastern Patagonia during the late Holocene.     

Seismic Vulnerability of Building Contents for a Given Occupancy Due to Multiple Failure Modes

A methodology is presented for assessing the seismic vulnerability of inventories of contents to multiple failure modes. An ordering method to find out probabilities of failure of a conditional mode upon the survival of the other modes is applied. The procedure considers the statistical correlation of failure modes due to the dynamic response, such as sliding and/or overturning, of contents and also to non structural components. This methodology was applied to inventories of four types of occupancy (house, school, office, and hospital) located in Mexico City, considering that all contents are situated at ground level. Expected damage functions for these inventories show large differences between them, the house and school inventories being the least vulnerable, and the hospital inventory, the most vulnerable, even for low intensities.     

Optimal Spectral Acceleration-based Intensity Measure for Seismic Collapse Assessment of P-Delta Vulnerable Frame Structures

This study proposes an “optimal” spectral acceleration-based intensity measure (IM) to assess the collapse capacity of highly inelastic frame structures vulnerable to the P-delta effect. The IM is derived from the geometric mean of the spectral pseudo-acceleration over a certain period interval. The lower bound period of the averaging interval is related to the mode in which 95% of the effective modal mass is exceeded. The upper bound period is 1.6 times the fundamental period. This IM provides minimum, or close to the minimum, dispersion for frames with different fundamental periods of vibration, or number of stories.     

Slave Communities and Pottery Variability in Western Brazil: The Plantations of Chapada dos Guimarães

In the region of Chapada dos Guimarães, Western Brazil, planters relied heavily on slave labor during the eighteenth and nineteenth centuries. In this article, we examine the locally produced pottery found on slaves contexts in five rural sites of this region. Based in data from probate inventories and the pottery decorative variability we suggest that slaves used decorated pottery to express cultural and social differences.