Experimental micromorphology in Tierra del Fuego (Argentina): building a reference collection for the study of shell middens in cold climates

Commonly used in archaeological contexts, micromorphology did not see a parallel advance in the field of experimental archaeology. Drawing from early work conducted in the 1990’s on ethnohistoric sites in the Beagle Channel, we analyze a set of 25 thin sections taken from control features and experimental tests. The control features include animal pathways and environmental contexts (beach samples, forest litter, soils from the proximities of archaeological sites), while the experimental samples comprise anthropic structures, such as hearths, and valves of Mytilus edulis (the most important component of shell middens in the region) heated from 200 °C to 800 °C. Their micromorphological study constitutes a modern analogue to assist archaeologists studying site formation and ethnographical settings in cold climates, with particular emphasis on shell midden contexts.     

Evolution of the Concept of ‘Extracellular Matrix’ in the Brain

The question as to whether an extracellular matrix exists between cells in the adult brain has been debated since the end of the last century. In the early years, zones containing neuropil and glial processes were mistakenly believed to represent this substance. But Golgi's discovery of the “perineuronal net” paved the way for future study of the true extracellular matrix. In the 1950s, application of histochemical techniques established the existence of interstitial material between nerve cells. Unfortunately the similarity between the pericellular distribution of this material and Golgi's “pericellular nets” was overlooked. The detection of an extracellular volume fraction in the central nervous system furnished further indirect proof for the existence of an extracellular matrix in the brain. However, the repeated failure of electron microscopy to reveal a substantial space between cell processes undermined the acceptance of the concept of “extracellular matrix” in the central nervous system. Nowadays this concept has, however, been firmly established.     

What Kind of Entrepreneurship Drives Regional Development in European Non-core Regions? A Literature Review on Empirical Entrepreneurship Research

Regional policies across Europe aim at stimulating regional development in non-core regions through fostering entrepreneurship. However, the policies applied in non-core regions and the concepts of entrepreneurship these policies are based on differ. Therefore, the goal of this review is to identify different understandings of entrepreneurship and their role for regional development processes in European non-core regions. To this end, empirical studies investigating entrepreneurship in European non-core regions from 1999 to 2011 were analysed. The results of the analysis are presented along three drivers and outcomes of entrepreneurship identified inductively from the literature: innovation, social capital and institutional change. We made out seven different types of entrepreneurship in European non-core regions. These seven types of entrepreneurship comprise particular mechanisms through which they stimulate regional development. Further research should study the interplay between these different mechanisms of regional development in non-core regions which may induce a more territorial approach to understand entrepreneurship in non-core regions across Europe.     

Effects of Geometrical Features on the Seismic Response of Historical Masonry Towers

ABSTRACT

Historical masonry structures are often located in earthquake-prone regions and the majority of them are considered to be seismically vulnerable and unsafe. Historical masonry towers are slender structures that exhibit unique architectural features and may present many inadequacies in terms of seismic performance. The seismic protection of such typologies of structures and the design of effective retrofitting interventions require a deep understanding of their behavior under horizontal loads. This paper presents the results of the seismic performance evaluation of historical masonry towers located in Northern Italy. A large set of case studies is considered, comprising a significant number of towers with high slenderness and marked inclination. First, a preliminary assessment of the dynamic behavior of the different towers is carried out through eigenfrequency analyses. Then, non-linear dynamic simulations are performed using a real accelerogram with different peak ground accelerations. A damage plasticity material model, exhibiting softening in both tension and compression, is adopted for masonry. The huge amount of results obtained from the non-linear dynamic simulations allows a comparative analysis of the towers to be performed in order to assess their seismic vulnerability and to show the dependence of their structural behavior on some geometrical characteristics, such as slenderness, inclination, and presence of openings and belfry. The evaluation of different response parameters and the examination of tensile damage distributions show the high vulnerability of historical masonry towers under horizontal loads, mainly in the presence of marked inclination and high slenderness. Some general trends of the seismic behavior of the towers are deduced as a function of the main typological features.     

Success of a flexible behavior. Considerations on the manufacture of Late Epigravettian lithic projectile implements according to experimental tests

It is generally recognized that the function and modality of hafting are the main factors influencing mental templates, and consequently, stone tool standardization. But what role do technical knowledge and traditions play? In this study, we investigate the interaction between mental templates and technological choices in the manufacture of Late Epigravettian projectile implements. The examined specimens come from different dwelling phases of the Dalmeri rock shelter (Italian Alps). Technological analyses suggest that lithic production systems gradually simplified their structure over time, implying a shift in technical investment from shaping on the core to a subsequent shaping on the derived flake blank. However, correlations between the dimensions and morphological features among the armatures from the different units suggest that mental templates remained unchanged throughout the Alleröd. Experimentation attests to the frequent combined application of different retouching techniques. Further, the variability in their arrangement denotes the absence of strict rules and the Epigravettian capability to recognize the most situationally suitable method. In the Dalmeri rock shelter, the standardization of lithic projectile implements is therefore a result of flexibility in retouching, framed in a production system characterized by a progressive simplification. A such rapidly produced and responsive technology must have been encouraged by Late Glacial climatic and environmental changes and the occupation of alpine territories previously inaccessible. Thus, the flexibility of technical behaviors turns out to be a key element in the transformation of Late Epigravettian societies during this period, enabling them to adapt and evolve in response to environmental, social, and economic changes.     

Multi-resolution morpho-bathymetric survey results at the Pozzuoli–Baia underwater archaeological site (Naples,Italy)

Here we show the results of two morpho-bathymetric surveys carried out on the underwater archaeological area of the Pozzuoli Bay (Naples, Italy). Such area is enclosed in the Campi Flegrei active volcanic complex, where bradyseism and recent volcanic activity strongly influenced the coastline shape over the last 2 Ka. The Digital Elevation Model (DTM) of the seafloor allowed to draw the main archaeological features of the Bay, that also include the military complex of Portus Iulius and the ancient thermal and villa complex of Baianus Lacus. The extraction of archaeological features from DTM was achieved thanks to the use of a GIS-derived tool based on the profile curvature algorithm. Thus, the Villa dei Pisoni (1st Century B.C.) and the thermal complex of Secca delle Fumose were investigated by using ultra-high resolution DTMs, that show the presence of Roman pilae for the protection of coastal buildings and also the inner planimetry of the Villa dei Pisoni complex. The observation of coastal engineering structures give also the opportunity to formulate some hypothesis on the evolution of morphology and of the sedimentary pattern of the area, while depth of archaeological remains allowed a rough computation of the rate of subsidence, resulted to be 2.55 (±0.5) mm/y for the Eastern sector (Pozzuoli) and 2.90 (±0.5) mm/y for the western (Baia).     

A Further Proposal for the Hull Lines of the Madrague de Giens Ship (c.70 BC)

A review of studies carried out since 1978 on the Madrague de Giens ship remains have enabled a reassessment of the vessel's shell‐first construction process. Hypotheses concerning moulding criteria are developed, with the profile (sheer plan), main cross section (body plan), and active sections and reference planks used to mould the hulll proposed and evaluated. These are compared to the Marsala (3rd century BC), and Yass?ada 2 (4th century AD) ships, which have similar wine‐glass‐shaped bottoms. Some aspects of these moulding criteria appear common to those used in the Mediterranean during the Middle Ages and the Renaissance.