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101.
Anca D. Cristea 《Journal of regional science》2023,63(4):947-980
City officials are continuously working to attract airlines willing to fly to new destinations. The inherent expectation is that a more extensive aviation network stimulates economic growth. This paper investigates empirically the causal implication of this hypothesis. Using data on nonstop flights by origin and destination over the period 1984–2013, we propose a new measure for a metropolitan area's connectivity to the national aviation network. We then use this measure to investigate its contribution to local economic development, as captured by the growth in population, in total employment, in per-capita income, and new firm entry. To ensure causality, we use instrumental variable methods that exploit geography and destination airports growth as a way to capture the exogenous variation in the likelihood to add new travel routes. Our results suggest that a metropolitan area's air connectivity, resulting from an expansive local aviation network, has a positive effect on population, on employment and on the number of businesses established in that location. 相似文献
102.
This paper reports on the pathology and discrete traits of 1388 vertebrae uncovered from a mass burial site at ‘Mamilla’ cave, Jerusalem, dated to the Byzantine period. Observations of the vertebrae were aimed at reconstructing an anthropological profile of the population, by describing such factors as the frequency of pathology and discrete traits, and age at death of the population. The results show that most of the victims were relatively young, and that they differed significantly in their epigenetic traits from Jews and nomadic Arabs. The results reinforce earlier assumptions that the skeletal material excavated at Mamilla cave represents the Christian population of the city, massacred by the Persians in 614 ad . Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
103.
抗战时期,中国出现了一场自东向西的人口大迁徙,随着大量人口及政府机关、厂矿、企业、文教团体迁入西部地区,给当地的经济、政治、思想文化产生很大影响,这些影响对于促进贵州社会进步与发展起到很大作用。 相似文献
104.
Jeff T. Williams 《International Journal of Osteoarchaeology》1992,2(2):131-138
Several errors in the early literature discussing life-table analysis of skeletal populations are potentially misleading to the researcher unacquainted with the mathematical methods of palaeodemography. Additional errors document the hazards of borrowing life-table methods and equations from other applications without fully realizing their context, interpretation, and the potential restrictions on their use. A simple generalization of the life-table equations explicitly to reveal their dependence on the entry age and width of the age intervals used will facilitate the correct computation of life tables and readily accommodate the use of unconventional or otherwise non-standard cohorts. A general procedure for computing a life table for a skeletal population is presented, and a numerical example is included to illustrate the method. 相似文献
105.
Wim Van Neer Silvia Augustynen Thomasz Linkowski 《International Journal of Osteoarchaeology》1993,3(4):241-248
Daily growth increments in fish otoliths have been demonstrated for the first time on Quaternary sagittae from a late palaeolithic site in Egypt and they have allowed us to establish the season of fishing. Transverse sections of tilapia sagittae studied under light-microscope demonstrate that recrystallization during diagenesis renders the majority of the margins unreadable. The well-preserved otoliths, however, all have widely spaced outer growth lines, indicating that the fish died during a period of fast growth which coincides with the flood season. Moreover, counting the daily increments showed that late palaeolithic man captured the animals on the floodplain of the Nile after the maximum of the flood, when residual pools were present. 相似文献
106.
本文以枣庄市作为组群式城市的代表,在深入调查分析的基础上,着重探讨了枣庄市农业人口转化的结构特征及其形成原因,以期对正确引导城镇化的过程产生积极意义。 相似文献
107.
M. E. Lewis 《International Journal of Osteoarchaeology》2004,14(2):82-97
Reactive new bone on the endocranial surface of the skull in non‐adults has recently received a lot of attention in the palaeopathological literature. These features appear as layers of new bone on the original cortical surface, expanding around meningeal vessels, as isolated plaques, ‘hair‐on‐end’ extensions of the diploë or, as ‘capillary’ impressions extending into the inner lamina of the cranium. These lesions are commonly found on the occipital bone, outlining the cruciate eminence, but have also been recorded on the parietal and frontal bones, and appear to follow the areas of venous drainage. Although recognized as resulting from haemorrhage or inflammation, their precise aetiology is still a matter of controversy. This paper outlines their possible causes and examines their nature and distribution in a group of non‐adults from four archaeological sites in England. It is recommended that, when recording these lesions in the future, additional skeletal pathologies, the age of the child, and nature and distribution of the lesions also be taken into account. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
108.
109.
I. Ari M. A. Kurt I. H. Oygucu E. Sendemir 《International Journal of Osteoarchaeology》2005,15(2):140-145
The presence of a bony bridge in the (bridging trait) hypoglossal canal, with five different modes, was investigated in 25 adult male Byzantine (13th century) skulls. First, we re‐evaluated the viability of proposed classification schemes, then for the first time, provided information on the structural features of this part of the occipital bone in a population of Asia Minor. Analysis of the data revealed minor differences in the Byzantine population compared to those previously investigated. Diverse geographical sources may be beneficial in understanding the role of developmental and genetic factors in bridging trait. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
110.
抗战时期浙江省的人口迁移与地域分布 总被引:5,自引:0,他引:5
抗战时期浙江省的人口迁移总数约有 5 0 0万人 ,其迁移情况极为复杂。其中 2 0 0余万人迁至省外 ,主要分布于闽、赣、皖、沪和华中、西南各省。大部分移民是在省内迁移。战时浙省移民迁移持续时间较短 ,最终转化为移民的只是少数。由于种种原因 ,战争期间即有部分移民回迁。战争结束后 ,绝大部分移民均回迁原住地。难民迁移的最根本最内在的动力来自经济和政治因素 ,尤其是经济因素 相似文献