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News wire services were established in the United States in the mid-nineteenth century to gather and distribute news for local newspapers, using the new technology of the telegraph. With that early beginning in the era of electronic communication, the expansion of news wire services spans the change from a society of local communities to a more nationally integrated society. This paper assesses the importanceof changes in the medium's spatial organization which promoted national culture. The first wire services were local, ad hoc groups, organized to achieve greater efficiency in news-gathering. Formal services were first organized on a local basis, but in 1848 they began to sell news to the major urbanized portions of the United States. As the nation grew, the desire for greater efficiency conflicted with the desire for greater autonomy. Regional wire services persisted from the 1860s to the 1880s but after the 1880s, a tenuous national organization was achieved, cementing itself into a national system after the turn of the century. Efficiency in news collection was the primary reason for the increasing scale of news collecting groups. Each step toward larger spatial coverage, fed the growth of a complex interdependent urban system.  相似文献   
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In 1985 a Neanderthal skeleton was found in the cave of Kebara in southern Mt. Carmel. Electron spin resonance (ESR) dates have been obtained on tooth enamel of gazelles found in layer X, just overlying the layer in which the skeleton was found. Assuming early uptake of uranium by the teeth, they yield an age of 60 ± 6 ka; assuming gradual, linear uptake of uranium yields an age of 64 ± 6 ka. Both age estimates are consistent with a previous estimate for the skeleton, based on TL dating of burnt flint, of 60 ± 4 ka.  相似文献   
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Pompeiian-style (hourglass) grain mills are common at many Roman sites within the circum-Mediterranean countries. Three examples are known from Corfe Mullen, London and Hamworthy in southern Britain. Petrographic examination, chemical and microprobe analyses indicate that the Corfe Mullen millstone and the London donkey mill were imported from central France into southern Britain. The Hamworthy mill should be designated a ‘flat donkey mill’, and represents a recent (post-Roman) import from a volcanic source in Sardinia. There is no evidence of importation of Roman donkey mills from Germany or for transportation of such mills (or stylistic derivatives) north of London.  相似文献   
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Seleucia Pieria: an ancient harbour submitted to two successive uplifts   总被引:1,自引:0,他引:1  
Historical sources ascribe the foundation of Seleucia (Seleukeia) Pieria to Seleucos I Nikator, shortly before the foundation of Antioch in the late 4th century BC. The Seleucia Pieria site seems however to have been inhabited earlier, perhaps from around 700 BC, possibly by a Greek population under an Assyrian ruler. The city became of considerable military importance during the wars between the Ptolemies and the Seleucids; it was occupied by the Romans in the 1st century BC, but had practically disappeared in the 6th century AD.
Geomorphological surveys in the area have revealed the existence of elevated marine notches and rims bioconstructed by vermetids, oysters and calcareous algae, which occasionally erode or intersect the archaeological sites, showing that two rapid land uplift movements, probably of seismic origin, took place during the late Holocene. The first movement, which occurred about 2500 ± 100 years bp, was the strongest one and caused a local vertical displacement of about 1.7 m, which may have severely affected the earlier Greek settlement. Though several earthquakes are reported to have occurred in the area during the following ten centuries, none of them seem to have been strong enough to cause significant vertical displacements. The second movement occurred around 1400 years bp, probably in May 526 AD, when a great earthquake followed by tsunami waves is known to have caused devastating damage in Antioch and Seleucia. According to geomorphological data supported by several radiocarbon dates, the earthquake was accompanied by a 0.7 to 0 8 m upheaval. This seismotectonic event also caused a rapid silting of the Seleucia Pieria closed harbour basin and entrances, thus preventing its further use.  相似文献   
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In recent decades the Uruk and Jemdet Nasr periods of the fourth millennium B. C. in Mesopotamia have been the subject of considerable research by scholars of the ancient Near East. Interests in and interpretations of these periods have focused on their credentials as early states, urban societies, and the immediate antecedents of Sumerian civilization. In this overview, I first present a brief historical background on the study of these periods, followed by a critical review of recent approaches that have had significant impacts on current directions of research and understanding of the fourth millennium. Finally, I suggest some research avenues currently being tentatively explored that may be especially appropriate for developing further our understandings of these periods.  相似文献   
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This article assesses the impact on public land management policy in the west following a decade's experience under the Federal Land Policy and Management Act (FLPMA). The assessment first describes the political and institutional forces that converged to produce the Bureau of Land Management's (BLM) Organic act and then identifies three major policy innovations found in the Act. In conclusion, the article assesses the impact of these policy innovations of FLPMA on management of the public lands.  相似文献   
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