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1.
Igor V. Volvenko Andrey V. Gebruk Oleg N. Katugin Georgy M. Vinogradov Alexei M. Orlov 《Geographical Research》2023,61(4):503-511
Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach. 相似文献
2.
Igor Koudriavtsev Valentin Dergachev Yury Nagovitsyn Maxim Ogurtsov Högne Jungner 《Geochronometria》2014,41(3):216-222
Radiocarbon 14C is a cosmogenic isotope, which is most extensively used by scientists from a wide variety of fields. Its rate of generation in the atmosphere depends on solar modulation and thus, studying 14C concentration in natural archives, one can reconstruct solar activity level in the past. The paper shows results of box-model calculations of generation of the 14C isotope in the atmosphere and its relative abundance during the time interval 1389–1800 AD, taking into account influence of changing climate. This interval includes the deep minimum of solar activity and period of significant change in atmospheric concentration of CO2 and global temperature. The performed analysis showed that concentration of 14C in the atmosphere reflects not only variations of the galactic cosmic rays intensity but as well changes of temperature and atmospheric CO2 concentration. It is shown that the decrease in CO2 concentration in the atmosphere during 1550–1600 can be connected with absorption of CO2 by the ocean surface layer. Thus, taking into account the climatic changes is an important condition for the reconstruction of solar activity in the past using data based on cosmogenic isotopes. 相似文献
3.
Igor Gurkov 《Eurasian Geography and Economics》2016,57(2):161-179
Using a series of interviews with the heads of Russian subsidiaries of Western multinational corporations and a unique database registering the openings of their new manufacturing plants in Russia during 2014–2015, we trace the changing demography, geography, and economics of foreign direct investments in industrial assets in Russia. We demonstrate that foreign companies in general were capable of overcoming the adverse economic conditions of 2015 and were able to complete their projects of installation of new factories that were launched in 2012–2013. More importantly, economic sanctions caused accelerated completion of previously started industrial works. Such new and upgraded factories not only target current opportunities and market niches in consumer markets but also aim at exploring possibilities in core industrial markets, including mining equipment, transportation equipment, and other types of industrial equipment. We also highlight the emergence of a new type of industrial project known as “fenced field projects,” which are new manufacturing facilities within the existing industrial sites of successful Russian firms. This new type is particularly attractive for companies in the machine-building and chemical industries. Fenced field projects can be either wholly owned subsidiaries or joint ventures, but the main feature of such projects is the active use of the developed physical and business infrastructure of the “hosting” Russian company. We demonstrate not only the changes in the geographic distribution of foreign direct investments in Russia but also the impact on medium-sized industrial towns (200,000–400,000 inhabitants), the most frequent location for industrial projects by foreign multinationals. 相似文献
4.
Igor Cusack 《Nations & Nationalism》2003,9(2):277-296
Whether cooking in a pot in the back yard, or in a modern kitchen, African women have generally prepared food for their men. More recently, they have collated and written cookery books both in the West and in Africa so that the ruling elites, mostly all men, have been able to display their new ‘national cuisines’ on their states’ official websites. This article reviews how ‘national cuisines’ have emerged recently in parts of Africa and then examines how these emerging cuisines might contribute to the gendering of African nations. It will also contrast Western notions of ‘the slender body’ with some African notions, of ‘eating out the body’, building a respectable but large body to construct an ‘authentic physical masculinity’ on the one hand, and a healthy and fertile wife and mother on the other. The article investigates how this might be reflected in African national cuisines. 相似文献
5.
In the last decades, particular attention has been paid to the seismic vulnerability of existing reinforced concrete buildings designed for gravity loads only. Such buildings, designed before the introduction of capacity design in modern seismic codes, are very common, particularly in seismic prone countries of the Mediterranean area. Due to poor detailing and lacking of capacity design principles, high vulnerability has been highlighted in several past studies. In this article, inadequate seismic response and peculiar damage pattern are investigated by means of shake table tests performed on a 1:2 scaled 3-story infilled prototype. Particular attention is given to the role of beam-column joints and frame-panel interaction. The effectiveness of the EC8-based assessment approach is then evaluated; both linear and nonlinear numerical models, with different levels of sophistication, have been implemented in order to explore their behavioral aspects. 相似文献
6.
Igor Primorac 《History of European Ideas》2013,39(1):109-111
How do Goya's representations of the body disrupt the Enlightenment's configurations of the corporeal? If for eighteenth-century aesthetics the body is both the site of ideal beauty and the limit of what can and may be represented, then Goya's panoply of monsters provides a way of understanding other modes of reason(ing), other ways of representing the body and its functions within culture. In his work there is a recuperation of those elements that seem to lie outside the ken of the Enlightenment project: physicality, animality, hybridity, the grotesque, the popular; a recognition of the animal nature of the body and the products of bodily impulses and forces. A rethinking of the body would incorporate an understanding of its role as a physical and social phenomenon in the constitution of the subject. Following on from Paul Ilie's concept of counter-rational Reason, which he defines as the opposite of a uniform centre of rationality in representative thought, the first half of my paper will consider Goya's problematization of representation. My analysis of a selection of drawings from the collection Los Caprichos (1799) will focus not just on the representation of bodies in the painter's work but on his exploration of bodies in their material variety—configurations of modes of constructing the body. This examination of Goya's prolific pictorial negotiations and adaptations of flesh and world will draw upon contemporary approaches to theorizing the body, namely the theories of Julia Kristeva and Elizabeth Grosz. 相似文献
7.
Laissez-faire governance and the archetype laissez-faire city in the USA: exploring Houston 总被引:1,自引:0,他引:1
Igor Vojnovic 《Geografiska annaler. Series B, Human geography》2003,85(1):19-38
This article explores the governance of Houston, the archetype laissez-faire city in the USA. The research examines the complexity of Houston's minimal government intervention rhetoric, which in practice involves extensive federal, state and local government involvement in economic development in combination with a disinterest in social service and income maintenance programmes. This governance strategy is outlined through an examination both of regional public policy and local public finances. The analysis illustrates that Houston's local governance has historically been based on a management approach that attempts actively to minimize costs for potential investors to locate in the City, through public intervention, while at the same time generating an unattractive urban environment for the socially marginalized — hence the disinterest in social services. Thus, despite the local laissez-faire rhetoric, government intervention in Houston's growth has been vital and has produced the extraordinary impacts usually expected from public involvement in local economic development. The foundations of this local governance strategy are both predicted and advocated by the public choice approach, a theoretical framework whose emphasis on inter-municipal competition advances management tactics based on maintaining low taxes and low expenditures on public welfare. The research also shows, however, that Houston is unique, when compared to other economically successful US cities, in following such an extreme approach of this management strategy. 相似文献
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9.
Igor Gutiérrez-Zugasti David Cuenca-Solana Pedro Rasines del Río Emilio Muñoz Silvia Santamaría José M. Morlote 《Journal of Anthropological Archaeology》2013
The role of coastal resources in the subsistence strategies of Palaeolithic human populations has only recently become an important topic in Old World archaeology. Information on the exploitation of these resources, both as foodstuffs and symbolic elements, can be used to infer the emergence of modern human behaviour as well as to track the diversification and intensification of human diet over time. The excavations carried out at El Cuco rockshelter, located in northern Spain have provided evidence for the exploitation of marine resources during the Early Upper Palaeolithic. The accumulation of Patella shells at El Cuco provides the largest accumulation and the first clear evidence of collection and consumption of molluscs during the Aurignacian on the Atlantic Façade of Europe. A deposit of ornamental shells appeared in a very homogeneous context dated to the Gravettian, suggesting that the shells belonged to the same item. The analysis of this evidence has allowed us to conclude that marine resources were systematically used at least from the beginning of the Upper Palaeolithic in the region. However, a comparison with the Mesolithic shows that intensive shellfish gathering did not occur until the end of the Upper Palaeolithic. Regarding the ornaments, it is interpreted that the identified shell beads were used as social or personal status markers. 相似文献
10.
Igor M. Villa 《Archaeological and Anthropological Sciences》2009,1(3):149-153
Pb isotopic analyses on metal artifacts help constrain their provenance. Useful and reliable data require analytical protocols
that ensure accuracy and monitor precision. The interpretation can sometimes be ambiguous because natural ore deposits frequently
have overlapping Pb isotopic compositions. In most cases, however, provenances can be reliably narrowed down. For the Alpine
region, a pattern of small, strongly localized mine exploitations in pre-Roman times, supplemented by some long-distance trading,
is taking shape. 相似文献