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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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Vlastimil Hart Tomá? Ku?ta Pavel Němec Veronika Bláhová Milo? Je?ek Petra Nováková Sabine Begall Jaroslav ?erveny Vladimír Hanzal Erich Pascal Malkemper Kamil ?típek Christiane Vole Hynek Burda 《PloS one》2012,7(12)
While magnetoreception in birds has been studied intensively, the literature on magnetoreception in bony fish, and particularly in non-migratory fish, is quite scarce. We examined alignment of common carps (Cyprinus carpio) at traditional Christmas sale in the Czech Republic. The sample comprised measurements of the directional bearings in 14,537 individual fish, distributed among 80 large circular plastic tubs, at 25 localities in the Czech Republic, during 817 sampling sessions, on seven subsequent days in December 2011. We found that carps displayed a statistically highly significant spontaneous preference to align their bodies along the North-South axis. In the absence of any other common orientation cues which could explain this directional preference, we attribute the alignment of the fish to the geomagnetic field lines. It is apparent that the display of magnetic alignment is a simple experimental paradigm of great heuristic potential. 相似文献
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Katharine Y. Ku Fred R. Butcher 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,631(1):70-78
Calmodulin coupled to Sepharose has provided a rapid and sensitive means of isolating a cyclic nucleotide phosphodiesterase activity which is stimulated by the calmodulin-Ca2+ complex, from rat parotid gland. Initial experiments established that phosphodiesterase activity sensitive to calmodulin and Ca2+ could not be demonstrated in crude extracts of rat parotid gland or after partial purification of rat parotid phosphodiesterase over DEAE-cellulose. However, it was possible to readily demonstrate the presence of a cyclic nucleotide phosphodiesterase activity regulated by calmodulin if the extracts were first purified by batch ion-exchange chromatography over DEAE-cellulose followed by affinity chromatography with calmodulin coupled to Sepharose. The batch ion-exchange chromatography step removed the major portion of free parotid calmodulin which could compete with calmodulin-coupled Sepharose for the proteins regulated by calmodulin. Thus, by employing an initial chromatography step over DEAE-cellulose to separate phosphodiesterase activity from calmodulin, it was possible to increase the recovery of calmodulin-sensitive phosphodiesterase after affinity chromatography with calmodulin coupled to Sepharose. This approach should be useful for demonstrating the presence of and for purifying other parotid proteins regulated by calmodulin. 相似文献
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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
10.
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