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71.
Juan M. Diederle 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):589-594
Diederle, J.M., 1.8.2015. Systematic status of the Miocene darter ‘Liptornis’ hesternus Ameghino, 1895 (Aves, Suliformes, Anhingidae) from Patagonia, Argentina. Alcheringa 39, 589–594. ISSN 0311-5518.Liptornis hesternus was established by Ameghino in the late 1800s on the basis of a cervical vertebra (NHMUK-A599) from the Santa Cruz Formation (Santacrucian, South American Land Mammal Age, early Miocene, Burdigalian Stage) of Patagonia, Argentina. Although taxonomic attributions were controversial, the specimen is now confidently assigned to Anhingidae. Recently, however, L. hesternus was designated a nomen dubium because of its uninformative diagnostic characters and apparent loss of the holotype. Nevertheless, NHMUK-A599 has been relocated and is redescribed here prompting referral to Anhinga. A combination of traits are shared with the extant Anhinga anhinga and A. melanogaster, and the material is dimensionally compatible with A. anhinga. The estimated body size of NHMUK-A599 would have been larger than A. minuta but less than A. grandis, A. subvolans, A. fraileyi and A. walterbolesi. Finally, Anhinga hesterna is considered valid and represents the stratigraphically oldest occurrence of the genus in South America and the southernmost yet recorded.Juan M. Diederle [juandiederle@cicyttp. org. ar], Laboratorio de Paleontología de Vertebrados, Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción (CICYTTP-CONICET), Materi y España, E3105BWA Diamante, Entre Ríos, Argentina. 相似文献
72.
Juan Martínez Millán 《Romance Quarterly》2013,60(1):54-63
The pattern of Latin American Boom criticism developed by Donald L. Shaw established that Juan Rulfo's protagonists are universal, not regional. In this interpretative mode, espoused by Graciela B. Coulson and others, Rulfo's characters are viewed as powerless to alter their own destinies. Humans are dominated and doomed by the hostile natural world that surrounds them. However, through a detailed analysis of Rulfo's technique and the internal and external structure of two of Rulfo's short stories in El llano en llamas—“No oyes ladrar a los perros” and “Es que somos muy pobres”—a new theoretical framework emerges for the study of Rulfo's work. In these two stories, Rulfo imagines the llano as a space that individuals control through their personal choices and actions. This article proposes, therefore, that Rulfo's protagonists are not victims of their environment, but rather the perpetrators of its violence. 相似文献
73.
Neus Isern Joaquim Fort António Faustino Carvalho Juan F. Gibaja Juan José Ibañez 《Journal of Archaeological Method and Theory》2014,21(2):447-460
We apply GIS techniques to analyze a carefully selected database of 93 Early Neolithic sites in the Iberian Peninsula. This allows us to study the spatial dynamics of the Neolithic transition in Iberia. We study how the Neolithic was introduced into the peninsula in order to test the hypothesis that the Neolithic was introduced almost simultaneously from two sources: one at the northeast (via the Mediterranean coast) and another one at the south (possibly from Northern Africa). We also analyze how the expansion of the Neolithic transition took place within the Iberian Peninsula and measure local rates of spread in order to identify regions with fast and slow rates (such as the slowdown at the Cantabrian coast). In addition, we attempt to reproduce the main results obtained from the GIS analysis by applying reaction–dispersal models to the expansion of the Neolithic transition in the Iberian Peninsula. We conclude that a model with two sources is a reasonable assumption that agrees better with the archaeological data available at present than a model with a single source. 相似文献
74.
人工神经网络:一种新的旅游市场需求预测系统 总被引:4,自引:0,他引:4
本探究了人工神经网络(ANN)作为一种新型的预测系统在旅游市场需求研究中的重要性,并指出:在对旅游需求进行预测时,人工神经网络较之多元回归分析方法适用范围更广,显性更强。 相似文献
75.
第二轮修志如何落实《关于第二轮地方志书编纂的若干意见》和《地方志书质量规定》等文件提出的地方志工作质量和志书质量标准体系,成为史志工作者的紧要任务。山东省结合《山东省志》的编纂,就质量管理体系建设进行了探索和思考:一是树立全面质量管理理念,以质量第一为原则,指导全方位工作;二是建立健全质量管理组织机构体系,确保组织到位;三是制定全面的制度规范体系,提供制度保障;四是构建严格的质量监控体系,强化质量监督;五是加强队伍建设等,营造良好的质量保障机制;六是不断积累和总结,形成持续改进的质量管理机制。 相似文献
76.
João Marreiros Juan Gibaja Nuno Bicho 《Archaeological and Anthropological Sciences》2018,10(3):631-645
During the Upper Paleolithic, lithic variability is one of the most important keys to recognize hunter-gatherer behavior, technology, ecology, and social dynamics. The origin and expansion of Gravettian populations in Eurasia has been seen as one of the most critical episodes in human evolution, argued to be the first clear evidence of the so-called polymorphism among modern human populations. In the case of southern Iberian Peninsula, recent data have shown a new regional and diachronic organization for the Gravettian occupation in this region. Therefore, the interpretation of such variability is one of the most important questions, and functional analysis is a fundamental proxy to recognize human technological, settlement and ecological adaptations as major factors for this polymorphism. This study focused on lithic use-wear analysis of the Early Gravettian of Vale Boi (southern Portugal), in order to understand lithic technological organization and variability within and between occupations at the site. Results show similar patterns between assemblages, showing that different materials were worked at the site, although showing reduced time of work, low variability and percentage of pieces used. Unlike other Gravettian contexts in southern Iberia, the Early Gravettian from Vale Boi is characterized by some variability of backed points, marked by the predominance of bipointed double-backed bladelets. Functional analysis of the Early Gravettian lithic industries of Vale Boi provide a new insight to interpret human technology and settlement strategy during the onset of Upper Paleolithic industries in western Eurasia. 相似文献
77.
Setting limits on government action is critical to economic development. Some forms of government organization, such as market-preserving federalism, seem effective to protect property rights in the long term with good results for economic efficiency. Spain endowed its regions with “Statutes of Autonomy” in the 1980s thus moving from a centralized to a decentralized form of government. It renewed and expanded some of the statutes in the 2000s. This article investigates whether these two waves of regionalization, which had their own characteristics in each region, had led to positive effects on economic performance. Using a novel autonomous region/country-matched balanced sample for the period 1950–2016, we apply the synthetic control method and compare the economic growth trajectories of Spanish regions with their synthetic control groups not affected by the regionalization process. We show that the first wave of “Statutes of Autonomy” had a positive but temporary economic growth impact. By contrast, the second wave of regionalization of the 2000s is associated with a negative growth impact. 相似文献
78.
马克思通过对宗教的批判确立了批判哲学的双重逻辑,即政治经济学批判与思辨哲学批判的统一,实现了哲学研究范式的历史转向。哲学的历史转向并不是说哲学成为历史学,而是强调哲学研究与历史研究的内在关联,即哲学摆脱了纯思辨的性质转向对人之存在的历史性研究,历史学既是建立在哲学研究的基础之上,同时也成为哲学研究的重要构成部分。从而将历史的事实、历史的逻辑和人之存在的历史性三者统一起来,超越了以往全部关于人类历史的学说,建构了一种全新的历史解释模式——生成论的历史解释模式。 相似文献
79.
Juan Manuel Cano Sanchiz 《Industrial archaeology review》2018,40(2):103-116
ABSTRACTMaterial sources have done little to contribute to research on Brazilian railway history (except for heritage studies and history of architecture). This interdisciplinary case study focuses on archaeological evidence to reflect on topics not often discussed in Brazil: the physical and functional configuration of the workplaces related to railways; the changing of these spaces through time due to the evolution of technology; and their characterisation as highly globalised sites. In doing so, we take the railway workshops of Jundiaí (São Paulo) as a study sample and analyse it under the light of the expansion of industrialisation from the World's great powers to its outlying economies. 相似文献
80.
María Del Rocio Moreno-Enguix Juan Gómez-García Juan C. GóMez-Gallego 《European Planning Studies》2012,20(2):321-340
Regional policies seek to enable regions to increase their competitiveness and development, and as such one priority objective of activities financed by Structural Funds is higher employment, higher productivity and economic activity. How efficiently the regions apply the funds is a fundamental issue for the development and continuity of regional policies. We, therefore, consider that determining the efficiency of European regional policies is an issue of high importance, and this is the main aim of this study. We have considered it appropriate to use the available information to apply a mathematical technique known as data envelopment analysis, which allows us to calculate the technical efficiency and inefficiency of the Structural Funds applied in the Objective 1 regions for the period 2000–2006. Furthermore, we wish to determine if the regions have been more efficient in increasing their levels of employment or in increasing productivity. Our study applies this methodology along with other methods such as regression analysis, profit analysis and factorial analysis to determine the variation in the rate of unemployment and productivity in these European Regions. The study reveals that only eight regions are efficient, although none of them is in all the models run. 相似文献