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1.
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 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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While food allergy prevalence has been studied at the national level, we know little of food allergy prevalence or perceptions of prevalence/management at the local level. This paper uses Waterloo Region as a case study to 1) document self-reported individual and household food allergy and sensitivity prevalence at the local level; 2) investigate perceptions of food allergy prevalence; and 3) explore perceived confidence in anaphylaxis management. Survey data were collected from January to March 2019. Respondents (n = 500) self-reported individual and household food allergy and sensitivity, estimated the percentage of Canadians with food allergy, and were queried about their knowledge of food allergy management. Prevalence estimates were weighted to the structure of the 2016 Canadian Census, and univariate and bivariate analysis were conducted. Prevalence of self-reported food allergy was 12.1% (95%CI, 8.8%-15.3%), and prevalence of self-reported food sensitivity was 26.3% (95%CI, 21.9%-30.7%). When asked to estimate the percentage of Canadians with food allergy, the mean perceived percentage was 35.1% (SD = 22.96). Self-reported prevalence of food allergy appears higher in Waterloo Region, and the estimated percentage of Canadians with food allergy is inflated. Understanding prevalence and perceptions at the local level is important for targeted allocation of public health resources to ensure safe spaces for individuals with food allergy.  相似文献   
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Agentes de su propia libertad. Los esclavos de Lima y la desintegración de la esclavitud, 1821–1854. By CARLOS AGUIRRE. Lima: Fondo Editorial Universidad Católica, 1993. Pp. 333.

Slavery and Abolition in Early Republican Peru. By PETER BLANCHARD. Delaware: Scholarly Resources, 1992. Pp. xx, 247.

Paying the Price of Freedom: Family and Labor among Lima's Slaves, 1800–1854. By CHRISTINE HÜNEFELDT. Berkeley: University of California Press, 1994. Pp. xi, 269.

Safari africano y compra‐venta de esclavos para el Perú (1412–1818). By FERNANDO ROMERO. Lima: IEP‐UNSCH, 1994. Pp. 275.  相似文献   

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Relatively little is known about the possibilities and limitations of voluntary public programs. The so-called 33/50 Program for reducing releases of certain toxic chemicals into the environment provides a useful instance for examination. In an investigation of toxics-reduction outcomes, with states as units of analysis, economic and policy variables help to explain the results. In particular, channels and approaches used In communicating policy intentions are related to outcomes. Voluntary programs can make a difference, but the details of execution, including the extent and nature of field efforts, influence outcomes.  相似文献   
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It is shown that audience members actively select amongst available programmes on television. This selection is based upon the social role and situational characteristics of the viewer and it is also directly related to the reasons given by viewers for watching television.

Patterns of programme selection are related to three clusters of needs and reasons. The two most important of these are composed of needs relating to information and diversion. The least important cluster is concerned with the self and social contact.

Escape and diversion needs are satisfied by almost any programme; selection is minimal by those viewers expressing these needs. Information needs are best satisfied by news and other informational programmes, while social and self needs are best satisfied by quiz and variety programmes, popular drama and movies.  相似文献   

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