The Shaking Frequency Effect in the Dynamics of a Model Sandy Layer

Experimental results showing the frequency-dependent behavior of both dry and saturated sandy layers subjected to a horizontal excitation on a shaking table are presented. The largest settlements of a dry layer correspond to two specific frequencies. In the case of a saturated layer, there is a single peak frequency corresponding to the largest depth of sinking of a measuring plate in liquefied subsoil. The first peak of settlements coincides with the single peak of sinking in liquefied soil. The eigenfrequencies of the layer were estimated. A modification of the compaction law was proposed for low shaking frequencies.     

Clusters versus Cluster Initiatives,with Focus on the ICT Sector in Poland

The article focuses on the topic of clustering, which has become a popular concept, both from the academic and political perspective, and as an efficient business model. The distinction between clusters, understood as geographical concentrations of specific industries, and cluster initiatives, understood as more formalized actions undertaken by regional actors, is proposed. The primary objective of this study is to verify if these two types of structures are overlapping each other. This problem arises because the motivation for forming some cluster initiatives may be different economic policy instruments rather than existing market potential of a specific regional economy. The study finds that not all of Information and Communication Technologies (ICT) cluster initiatives in Poland represent real concentration of ICT-related divisions included in statistical classification of economic activities in the European community Rev. 2 classification, as measured by location quotients (LQs) for indicators on employment, firms' incomes and number of enterprises. However, there is a visible pattern that the LQs are higher in smaller geographic areas (NUTS 4 (Nomenclature of units for territorial statistics)), which usually represent big cities, being the cores of cluster initiatives. The study also discusses the phenomenon of the internationalization of clusters and the value added to that process from forming formalized cluster initiatives, which create favourable institutional framework for transborder cooperation.     

Hunter–gatherer foraging ranges, migrations, and travel in the middle Holocene Baikal region of Siberia: Insights from carbon and nitrogen stable isotope signatures

Foraging ranges, migrations, and travel among Middle Holocene hunter–gatherers in the Baikal region of Siberia are examined based on carbon and nitrogen stable isotope signatures obtained from 350 human and 203 faunal bone samples. The human materials represent Early Neolithic (8000–6800 cal BP), Late Neolithic (6000–5000 cal BP), and Early Bronze Age periods (∼5000–4000 cal BP) and come from the following four smaller areas of the broader region: the Angara and upper Lena valleys, Little Sea of Baikal’s northwest coast, and southwest Baikal. Forager diets from each area occupy their own distinct position within the stable isotope spectrum. This suggests that foraging ranges were not as large as expected given the distances involved and the lack of geographic obstacles between the micro-regions. All examined individuals followed a similar subsistence strategy: harvesting game and local fishes, and on Lake Baikal also the seal, and to a more limited extent, plant foods. Although well established in their home areas, exchange networks with the other micro-regions appear asymmetrical both in time and direction: more travel and contacts between some micro-regions and less between others. The Angara valley seems to be the only area with the possibility of a temporal change in the foraging strategy from more fishing during the Early Neolithic to more ungulate hunting during the Late Neolithic–Early Bronze Age. However, the shift in stable isotope values suggesting this change can be viewed also as evidence of climate change affecting primary productivity of the Baikal–Angara freshwater system.     

Sourcing nonnative mammal remains from Dos Mosquises Island,Venezuela: new multiple isotope evidence

Archeological excavations of Amerindian sites on Dos Mosquises Island, Los Roques Archipelago, Venezuela, uncovered a wide range of evidence reflecting seasonal exploitation of local resources and multiple ritual depositions of large quantities of ceramic figurines, lithics, and faunal remains. Zooarchaeological analysis revealed the presence of modified and unmodified bones and teeth from numerous imported mammal species. Local geographic and environmental conditions preclude permanent establishment of terrestrial mammal populations and as such, there are no native mammalian taxa on the island itself or the surrounding oceanic archipelago. The presence of these faunal remains on Dos Mosquises can be attributed to the intentional movement of animal resources from the mainland to Los Roques by indigenous groups in the Late Ceramic Age (~AD 1200–1500). Despite attributions to a mainland source region, little else is known about the origins of these unique specimens. Here, we apply strontium (⁸⁷Sr/⁸⁶Sr), oxygen (δ¹⁸O), and carbon (δ¹³C) isotope analyses of tooth enamel from various archeologically recovered taxa including deer, peccary, tapir, ocelot, margay, opossum, fox, and weasel to investigate their geographic origins via comparisons with macro-regional models of precipitation δ¹⁸O and bioavailable ⁸⁷Sr/⁸⁶Sr. The ⁸⁷Sr/⁸⁶Sr results are highly variable both for the overall assemblage and between specimens within the same taxa, indicating origins from different geochemical environments of mainland South America. The combined archeological and isotopic evidence are consistent with origins within the late pre-colonial Valencioid Sphere of Interaction which encompassed the Lake Valencia Basin, surrounding regions, and several offshore island groups including Los Roques archipelago.     

The neolithic and early bronze age of the Lake Baikal Region: A review of recent research

Rich settlement and burial evidence from the Baikal/Angara region in Central Siberia provides one of the most promising opportunities in the global boreal forest for studying Holocene foragers. The Neolithic and Early Bronze Age prehistory of the region is known to western scholars only through a few English translations of the works of A. P. Okladnikov. Since the publication of Okladnikov's model, the region has witnessed large-scale archaeological fieldwork that has produced abundant quantities of new evidence. Moreover, the model has been partly invalidated by extensive radiocarbon dating. Research advances over the last couple of decades have augmented the area's previous reputation but have also revealed the need for new theoretical perspectives and modern analytical techniques.     

Prehistoric Seal Hunting on Lake Baikal: Methodology and Preliminary Results of the Analysis of Canine Sections

A number of archaeological sites on Lake Baikal revealed evidence of Neolithic and Bronze Age seal hunting. A collection of 35 canines from four sites was used to develop a methodology for analysing growth increments of canine dentine for the purpose of examining aspects of prehistoric seal hunting. Results from this preliminary analysis indicate that seal hunting at these sites was a seasonal activity confined to spring and early summer. Baikal seals were probably hunted in early spring for their meat, blubber and furs, and later in the season for their meat and skins.     

In search of a better method to distinguish artefacts from geofacts

Archaeologists use a method of evaluating the characteristics of flakes, called scoring, to distinguish geofacts (pseudo-artefacts or eoliths) from artefacts. Lower total scores are considered indicative of a natural source of the finds, while higher ones support the opposite. However, this method has some limitations. The most important are the small quantity of assemblages subject to such an analysis and the unclear boundary drawn by a ranking within a point-based score evaluation between collections with finds of cultural and anthropic origin. Here, we present a method that minimizes these limitations. It consists of a statistical approach using scoring percentages, a new method of visualizing them and the application of clustering. This way, we obtained clear differences between pseudo-artefacts and artefacts by considering flakes from six flint assemblages from Central Europe as well as an experimental assemblage.     

Radiocarbon method in monitoring of fossil fuel emission

The traditional radiocarbon method widely used in archaeology and geology for chronological purposes can also be used in environmental studies. Combustion of fossil fuels like coal, natural gas, petroleum, etc., in industrial and/or heavily urbanized areas, has increased the concentration of carbon dioxide in the atmosphere. The addition of fossil carbon caused changes of carbon isotopic composition, in particular, a definite decrease of ¹⁴C concentration in atmospheric CO₂ and other carbon reservoirs (ocean and terrestrial biosphere), known as the Suess effect. Tree rings, leaves, as well as other annual growing plants reflected the changes of radiocarbon concentration in the atmosphere due to processes of photosynthesis and assimilation of carbon from the air. By measuring radiocarbon concentration directly in atmospheric CO₂ samples and/or biospheric material growing in industrial and/or highly urbanized areas where high emission of dead carbon is expected, it is possible to estimate the total emission of dead CO₂. Based on equations of mass balance for CO₂ concentration, stable isotopic composition of carbon and radiocarbon concentration it is possible to calculate CO₂ con-centration associated with fossil fuel emission into the atmosphere. The procedure use differences between the radiocarbon concentration and stable isotope composition of carbon observed in clean areas and industrial or/and highly urbanized areas.