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111.
The study of the Sardinian Bronze Age (Nuragic period) and the factors which created and maintained an island-wide identity as seen through the presence of its distinctive nuraghi has received considerable attention; however, the amount of research directly related to the stone tools of the era has been relatively limited despite the wealth of knowledge it is capable of yielding. This research hopes to contribute to Sardinian archaeology through the study of ancient technology, specifically obsidian lithic technology, by combining typological information with source data gleaned from the use of portable X-ray fluorescence spectroscopy. This research also explores temporal changes in the acquisition of obsidian raw materials and the corresponding changes in how the obsidian was used. The results provide precedence for future work in Sardinia and create a model for integrating two types of analyses, sourcing and typological. By combining these results, it is possible to investigate ancient economies, exchange networks, and cultural values.  相似文献   
112.
The luminescence dating of the K-feldspar fraction is an alternative way for samples that cannot yield reasonable equivalent dose (De) from quartz fraction with very weak luminescence signal. For testing the reliability of the infrared stimulated luminescence (IRSL) dating of K-feldspar, luminescence dating was applied to quartz and K-feldspar fractions respectively for several Holocene samples in this study. K-feldspar apparent ages using routine single aliquot regenerative-dose (SAR) protocol, K-feldspar ages using g value correction method and ages from isochron dating method were compared with quartz ages. It is found that the g value correction method cannot give reliable ages due to the large errors induced during measurements. The isochron dating method is effective to the sample with problematically external dose rate. However, isochron dating may introduce a relatively greater error during grain sizes — De curve fitting, therefore this method could obtain low-resolution ages for Holocene samples. Even K-feldspar apparent age from routine SAR protocol is relatively younger by about 10% than the quartz age, it still could establish reasonable chronological framework for Holocene samples.  相似文献   
113.
Recent archaeobotanical studies in East Asia show that the use of wild food plants, particularly nuts, was important for not only hunter–gatherers but also early farmers. For example, recent archaeobotanical work has identified large quantities of nut remains from early Chinese rice farming sites dating 5,000–4,500 BC. In Japan, which introduced rice farming from China around 1,000–500 BC, archaeobotanical data have shown continued exploitation of nuts even after the introduction of rice farming. Therefore, the first appearance of farming does not appear to have immediately impacted the subsistence system, although it may have changed cultural perceptions of food plants, eventually rice replacing nuts as a staple food. To explain the cultural implications of this shift in emphasis, it is necessary to investigate people’s routine subsistence activities with reference to available ethnographic information on non-mechanised plant processing. The ethnographic data provide insights into ancient nut processing, including possible methods, tools, choices of working locations and labour scales. Conceptual modelling based on ethnographic observations of the range of nut-processing practices will also aid interpretations from newly developed methods, such as starch residue analyses. The resulting archaeobotanical, archaeological and ethnographic picture may help to further explore past social organisation and social perceptions of plant foods.  相似文献   
114.
While it is generally agreed that food processing has had a role in human evolution, the specific ways that is has affected our evolution are not well understood. Using a Niche Construction Theory (NCT) perspective, coupled with methodologies borrowed from “post-harvest” research in the plant sciences, this paper investigates the means and mechanism by which food processing is of evolutionary consequence. The central tenet of NCT is that organisms have an active role in their own evolution through reciprocal interactions with their environments; niche construction is understood to occur when organisms initiate long-term changes to their environments that modify the selection pressures on themselves and their descendants (and on other organisms in the environment). Humans and our hominin ancestors are considered to be the ultimate niche constructors due to our ability to modify selection pressures through diverse culturally generated and transmitted cultural means, i.e. cultural niche construction. In this paper, post-harvest methods are used to identify how food processing could feasibly have permitted hominins to modify their evolutionary selection pressures. Food processing is shown to facilitate access to increasing amounts of digestible nutrients and energy (kilocalories/kilojoules) as well as promoting increased dietary breadth and making possible the production of safer and more stable foods. It is argued that these advancements catalysed related technological and ecological skills and knowledge, which together with the nutritional benefits, further triggered changes in hominin brain and body and locomotory adaptations and increased longevity, disease prevention and juvenile survival rates.  相似文献   
115.
In this paper, a detailed overview of the Holocene evolution of the North Dvina river (ND) delta (southern White Sea) is presented; it is based on radiocarbon dating, geomorphological and other field surveys, and plant macrofossil and palynological data. We have identified three main stages of the delta evolution: estuary erosional (Allerød — 5700 cal BC), lagoon or tidal-marsh (5700 cal BC — 3700 cal BC) and fan-delta accumulative (3700 cal BC — present). These stages are correlated with local climatic curves, sea level changes, glacioisostatic raise curve and Baltic Sea stages. A variety of landforms has been identified and dated within the delta. These results help to explain the spatial and temporal patterns in the prehistoric human occupation of this area.  相似文献   
116.
The paper deals with dendrochronological and radiocarbon dating of subfossil trunks found in the basin of the Morava River. The research into subfossil trunks had been conducted in the Czech Republic in the past but the research stopped in 2001. 160 records of measurements of subfossil, predominantly oak trunk samples, are preserved from that time. Three years ago the research was reopened and again the most trunks were found in the basin of the Morava River. 92 samples of oak trunks and 7 samples of other tree species (poplar, elm, maple, beech) were taken from selected sites. The samples were processed in compliance with the standard dendrochronological methodology. To date the samples, Czech, Austrian, Polish and German standard chronologies were used. In cases when the dendrochronological dating was unsuccessful, the samples were sent for radiocarbon dating. In total, 35 samples were dated, mainly by the radiocarbon method. Subfossil trunks from gravel pit Tovačov were dated and classified into 4 different periods, the oldest being from 2780–2190 BC. In Osek nad Bečvou, the samples were taken from two sites. Whereas from the 4 trunks taken in the river channel each was from a different period, the trunks from the gravel pit come from 981–1015 AD. The trunks found in the Morava River basin near Strážnice were dated to the 10th–15th century. In the future, we expect to extend the amount of the acquired samples with the aim to create a link to the existing standard chronology or to create a long floating average treering curve.  相似文献   
117.
It is known from previous studies that qualitative and quantitative morphological attributes of food products and residues may permit the identification of different food processing activities in desiccated algarrobo (Prosopis chilensis and Prosopis flexuosa) remains. Experimental approaches are used here in order to (1) evaluate if those diagnostic features persist even after charring and (2) to use these results as a means of interpreting types of processing from archaeobotanical contexts of the Inka site of El Shincal. Experimentation was made on the basis of traditional practices which were registered during previous ethnobotanical work in the area. Diagnostic patterns of Prosopis flours and patay (bread), as well as of añapa/aloja (fresh and alcoholic beverages, respectively) and arrope (syrup) residues were stipulated for charred remains. In the specific case of El Shincal, specimens derived from flour manufacture (unrefined and refined) and añapa/aloja residues were recognized from different buildings. This must have implied a special organization of the production and the people working on that, in the sense of post-harvest intensification.  相似文献   
118.
The activities of jurists, they may be judges, lawyers or university teachers, occupy a central role in the maintenance of the political and social order of modern societies. In Germany the confrontation of the recent past provoked in the early 1960’s a large debate about the real foundations of the modern state and his role in the crisis of the modernity which have been pursuit in the course of the eighties issuing in the beginning of the century in the discussions about integration and a general order of values to be recognized by everybody.  相似文献   
119.
Among the various types of industrial solutions used to store goods and products, the light duty hand loaded shelving rack (SR) typology represents a very popular solution for domestic applications, libraries and for superstores/markets open to the public. Despite the limited cost, an eventual collapse could result in significant damage of stored goods, injuries, and potentially the loss of human life, with the possible consequence of a long suspension of commercial activities. This reflects directly on the great importance of a correct design that, despite the large use of SRs, is nowadays developed with approaches characterized by inadequate levels of reliability.

A research program on SRs is currently in progress in Italy, with the aim of improving the rules for both static and seismic design and this article presents a combined experimental-numerical study. Both component and pushover tests have been carried out, that are shortly summarized. Overall frame response has been simulated by means of advanced finite element software able to capture key features of the nonlinear response of slender frames with mono-symmetric cross-section members.  相似文献   
120.
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.  相似文献   
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