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21.
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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An investigation of three Andean towns in their regional setting forms the basis for an assessment of urban-rural demographic differences. The towns are found to have been ethnically distinct, with a larger proportion of whites than the mainly Indian rural areas. The urban populations also had a larger surplus of women, lower average marriage ages for women but lower proportions married, a higher illegitimacy rate and a slightly older age structure. Trends in urban districts differed from those in rural areas. The towns suffered major population losses, and their share of the regional population fell from nearly 10% in 1778 to around 5% in 1841. The factors affecting population trends are examined in order to identify those which had a differential urban-rural impact. Earthquake and warfare were of key significance. In a regional context of economic depression and population stagnation, these two catastrophes instigated a major urban recession. The three towns shared in the urban decline experienced in many parts of Latin America, but their recession was particularly pronounced owing to the impact of catastrophes.  相似文献   
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ABSTRACT Casinos are often considered as a “growth pole” strategy to revitalize dilapidated regions. However, voters often reject casinos due to their perceived adverse impact on crime. Using a quasi-experimental design we analyze the impact of the casinos on crime spillover from Atlantic City to other localities in the region. We found that the level of crime in localities adjacent to Atlantic City and along the major nontoll routes to Philadelphia and New York City up to approximately 30 miles from Atlantic City rose significantly following the introduction of casinos. Crime levels are higher than they would have been in the absence of casinos.  相似文献   
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