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Ballast stone deposits are a common feature of sediments in ancient harbour basins but are often overlooked as a potential source of archaeological information. Recent geophysical investigations at Caesarea Maritima in Israel have discovered a thick, laterally extensive ballast layer in the area seaward of the 1st c. BC Roman harbour. The ballast deposits were identified by low-relief mounds on the seabed with elevated magnetic intensities. Jet probing and excavation of magnetic anomalies at several locations revealed a 20–60 cm thick rubble layer containing large quantities of Late Roman and Byzantine pottery, local sedimentary boulders (kurkar sandstone, limestone cobbles) and foreign igneous and metamorphic boulders (granite, schist, volcanics; ca. 50%). The foreign boulders and pottery identify the rubble layer as ballast and ships refuse jettisoned by merchant ships outside the harbour. The strong magnetic contrast between the ballast deposits and the natural seabed sediments is attributed to the high magnetic susceptibility (>10−3 SI) of crystalline boulders and pottery materials within the ballast rubble.  相似文献   

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A marine geophysical survey was conducted at Caesarea Maritima, Israel, to map the buried structure of King Herod's Roman harbour. Magnetic surveys reveal the presence of an extensive hydraulic concrete foundation below the ruined harbour moles. The magnetic anomaly patterns indicate that the concrete foundation was laid out in header fashion along N-S and W-E trending segments to form two large 'artificial islands'. Magnetic lows within the structure identify baffles that were infilled with sand to stabilise the concrete foundation walls.
© 2004 The Nautical Archaeology Society  相似文献   

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A rich collection of waterlogged plant‐remains was recovered from the harbour at Caesarea Maritima, Israel. These remains were identified and represent several varieties of fruit, nut, cereal crop, crop by‐product and weed species. The two areas where remains were recovered provided assemblages that were different in composition. Trade or trash are the two interpretations discussed. In either case, however, the information derived from the assemblage is of archaeological importance, as the species present can aid in economic, dietary and trade reconstructions. © 2010 The Author  相似文献   

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The Arab Spring, which was launched in Tunisia, took the Arab Middle East by storm. Its results, to varying degrees, have been felt in every country in the region. In the Maghreb, three scenarios have been unfolding. Tunisia has seen the greatest changes with the country maneuvering its transition to democracy. Algeria — whose aims have not necessarily been a genuine transition to democracy, but to keep the status quo — has continued its process of reforms that started almost three decades ago. In Morocco, the leadership has used the Arab Spring to initiate a series of incremental reforms to further open up the political space, in a more controlled fashion.  相似文献   

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Candidates and nominees for statewide office in the United States do not emerge from random locations within states. In this paper, we argue that densely populated areas are more likely to both foster political ambition and to afford the resources that enable candidates to wage an effective campaign. Candidates and nominees for major statewide office originate from populous counties in numbers significantly out of proportion to these counties’ share of their state’s population. Meanwhile, aspirants virtually never emerge out of rural areas or small towns. The pattern holds for all candidates and nominees for both Senate and governor and for both major political parties. Regional biases are more pronounced for institutionally strong gubernatorial offices than for weak offices and among high quality nominees for statewide office than among inexperienced candidates. Given the importance of urban/rural cleavages in the American electorate, these findings raise fundamental questions about political representation.  相似文献   

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Abstract

It is still uncommon for foreign and national archaeological excavations in Morocco to include architectural or site conservators during the excavation and post-excavation periods. The few existing examples of conservation have all been carried out long after the site or the building had been excavated. The site conservation activities during the Aghmat excavations in summer 2006 illustrate how the presence of archaeological conservators, advising the archaeological team and implementing urgent interventions, has ensured a safe excavation and has contributed to the preservation of the physical integrity of the excavated buildings. The excavation of the imposing archaeological features of the medieval bath of Aghmat provided the first opportunity in Moroccan archaeology for Moroccan archaeological conservators to be involved in condition assessment, planning, and provision of conservation activities to preserve the bath.

The primary aim of this paper is to present the site conservation experience in the Aghmat project, which is the first such project to be initiated during an excavation, and to be conducted mainly by a Moroccan team; it aims also to highlight the conservation procedures adopted and to incite discussion.  相似文献   

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Theories and data do not always fit and sometimes are sources of conflicts among scientists. This is the case of a morphological structure, the perineuronal net, which was denied on the basis of an ideological conflict between two giants of neurosciences: Camillo Golgi and Santiago Ramon y Cajal. The perineuronal net is a reticular structure enveloping many neurons. Orginally reported by Golgi in 1893 and 1898 and confirmed by several authors before the turn of the century, the perineuronal net was used by Golgi to support the reticular theory of the organization of the nervous system. Ramon y Cajal, the paladin of the neuronal theory who had also observed this anatomical structure, denied its existence suggesting that it was a fixation artifact. After Cajal's statements, only a few Italian scientists continued to work in this field, and after the 1930s the perineuronal net was forgotten. Only the recent advances in histochemical and immunocytochemical technology confirmed the existence of this structure opening new fields in functional neuroanatomy and neuropathology.  相似文献   

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Harbour communities across Europe and the US are in the midst of major changes. Shifting trade regulations, declining supplies of fish, the rise of recreational boating and new shipping technologies have all contributed to these changes. In response, communities are undertaking major planning efforts to ensure that their harbours remain functional and prosperous. One example of this effort is the Port of Viana do Castelo, Portugal. The thesis of this paper is that unless small and medium sized harbours have a strong and planned sense of direction, they will suffer an economic decline and lose their historic and cultural character.  相似文献   

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