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1.
The advent of publishing anonymized call detail records opens the door for temporal and spatial human dynamics studies. Such studies, besides being useful for creating universal models for mobility patterns, could be also used for creating new socio-economic proxy indicators that will not rely only on the local or state institutions. In this paper, from the frequency of calls at different times of the day, in different small regional units (sub-prefectures) in Côte d''Ivoire, we infer users'' home and work sub-prefectures. This division of users enables us to analyze different mobility and calling patterns for the different regions. We then compare how those patterns correlate to the data from other sources, such as: news for particular events in the given period, census data, economic activity, poverty index, power plants and energy grid data. Our results show high correlation in many of the cases revealing the diversity of socio-economic insights that can be inferred using only mobile phone call data. The methods and the results may be particularly relevant to policy-makers engaged in poverty reduction initiatives as they can provide an affordable tool in the context of resource-constrained developing economies, such as Côte d''Ivoire''s. 相似文献
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P Burstyn 《BMJ (Clinical research ed.)》1980,280(6208):182-183
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Several LINE-1s have been isolated and characterized from genomic DNA of the vole, Microtus kirgisorum. Blot hybridization revealed specific restriction patterns of L1 elements in vole genomes. Rehybridization of the genomic
blot with a cloned 5′-end fragment revealed two major bands indicating the presence of two different L1 subfamilies. The copy
numbers are estimated for different parts of M. kirgisorum L1 elements. Data also demonstrate that most vole L1 elements are truncated at the 5′-end; however, in contrast to mouse,
the ORF1 copy number is higher in vole. A difference between the substitution rates of the ORF1 5′-region (approximately 330
nucleotides) and the rest of the L1 coding regions is revealed.
Received: 12 January, 1999 / Accepted: 18 March, 1999 相似文献
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Igor A. Mikhailopulo Nicolai E. Poopeiko Grigorii G. Sivets Natalia B. Khripach 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):383-384
Abstract Oxidation of 1a with DMSO-acetic or trifluoroacetic anhydride led to the formation of a mixture of epimeric gem-diols 2 and 3 in the ratios of ?3:1 and ?7:1, respectively. Reduction of this mixture with NaBH4 followed by benzoylation and chromatography afforded 4a and 5a. 相似文献
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In this article, we investigate the potential for detection and characterization of sinkholes under dense forest cover by using airborne laser scanning data. Laser pulse returns from the ground provide important data for the estimation of digital elevation model (DEM), which can be used for further processing. The main objectives of this study were to map and determine the geomorphometric characteristics of a large number of sinkholes and to investigate the correlations between geomorphology and vegetation in areas with such characteristics. The selected study area has very low anthropogenic influences and is particularly suitable for studying undisturbed karst sinkholes. The information extracted from this study regarding the shapes and depths of sinkholes show significant directionality for both orientation of sinkholes and their distribution over the area. Furthermore, significant differences in vegetation diversity and composition occur inside and outside the sinkholes, which indicates their presence has important ecological impacts. 相似文献
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