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1.
In this investigation terrestrial magnetic records for 1929–1985 from the Auroral Observatory in Tromsø have been examined for giant micropulsations (Pg). This period encompasses five solar cycles and supplements the work of Harang, who studied the records from the time such recordings started in Tromsø in March 1929 through March 1941. In agreement with Harang, an anticorrelation with the solar cycle is found in the frequency of occurrence of the micropulsations. A seasonal variation with maxima in March and September is clearly revealed, as already indicated in Harang's much more limited data set. Also in support of Harang, it is found that the period of oscillation tends to increase for long lasting pulsations and for recurring ones. Contrary to Harang, who found a daily maximum between 0100 and 0200 UT, however, we find the maximum to occur somewhere between 0200 and 0300 UT.  相似文献   

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Geomagnetic pulsations in the 0.1–2.5 Hz (Pc1–2) range recorded over 12 quiet summer days at six Antarctic stations between −62.3 and −80.6° invariant latitude were examined in order to map the spatial and temporal distribution of spectral characteristics. Ionospheric particle signatures associated with the magnetospheric cusp and boundary layer were deduced for three of these days using ground riometer, magnetometer and ionosonde measurements, and in-situ ionospheric particle data. Comparison with the magnetic pulsation data shows that specific Pc1–2 emissions are associated with these regions. Within the cusp, intense unstructured ULF noise in the 0.15−0.4 Hz range is observed. Less intense waves of this type are seen near the cusp location on mantle and plasma sheet boundary layer flux tubes. These emissions are quite distinct from the discrete, structured and narrowband emissions seen equatorward of the cusp. Whereas past discussions of cusp and cleft identification have usually focused on optical or satellite data, we conclude that ground-based observations of Pc1–2 pulsations can provide a more convenient, although less precise, monitor of high latitude features.  相似文献   

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This paper analyses the role of roadbuilding as a process of state territorialisation in post-war Sri Lanka. In the aftermath of a brutal civil war (1983–2009), and in lieu of a broader peace and reconciliation process between Sinhalese, Tamil and Muslim communities, road infrastructure has been promoted by the state as essential to the region's recovery and nation's sovereignty. Roads were to bring national unity and political integration. We interrogate such claims, drawing on fieldwork conducted in Jaffna and neighbouring areas to cast doubt on the prospects of new roads to ameliorate ethnic tensions. Rather, as militarised security discourses and policies continue to dominate the Sri Lankan public sphere, such schemes can be understood as part of broader Sinhala-Buddhist nationalist project to consolidate territorial control in restive parts of the country. Our research suggests that, rather than facilitating rehabilitation and recovery, road networks mirror pre-existing fault lines and entrench the privileged position of the military in Sri Lankan society. Such shifts do little to avail persistent minority sentiments of political marginalisation, aggravating social fractures and re-constituting the hegemony of Sinhala-Buddhist nationalism.  相似文献   

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This paper examines the practices and perceptions of corruption in two tsunami-affected villages in the Hambantota District, South Sri Lanka. Using an ethnographic approach to low level corruption, the paper focuses on narratives emerging from the study villages. Practices of corruption are associated with discretionary powers and the system of political patronage, which place local office holders, local politicians, and wealthy households on the receiving end of corrupt systems. Perceptions of corruption encompass ideas of morality and state–society relations. The manifestation of corruption in post-tsunami Sri Lanka is shown to coincide with a pre-existing unequal and iniquitous development landscape, which became enmeshed in circumstances characteristic of the post-tsunami environment. The paper highlights a theme neglected in the post-tsunami literature on Sri Lanka and contributes to the few intensive ethnographic accounts of corruption in South Asia. It emphasizes the broader relevance of the study for understanding issues of governance and post-conflict development in Sri Lanka.  相似文献   

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《Political Geography》2007,26(7):804-823
In this spatial statistical analysis, Hungary, though a small country in size (smaller than most states in the USA), is shown as having significant spatial clustering. On the basis of this spatial clustering, it is demonstrated that a political party, FIDESZ that had previously been associated with a different political bloc has been able, in a relatively short period of time of the 1990s in the post-Communist period, to occupy the vacant space on the ‘right’ and to integrate with the voters of the right-wing bloc.  相似文献   

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Field measurements of atmospheric absorption made in the wavenumber range 5–17 cm−1 are found to have values in excess of prediction based on absorption by monomeric water molecules. The measurements also show unexplained variations with time, although on average the absorption in the region of 7.1 cm−1 is found to be close to comparison laboratory values. The absorption measured in excess of water monomer prediction is analysed for its dependence on temperature. In common with the laboratory results, this is found to differ from prediction for water dimers in equilibrium. Results are also given for measurements in fog conditions.  相似文献   

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Understanding how to live successfully within our environment is among the most pressing challenges facing contemporary society. This paper probes the problem based on comparative analysis and discusses the relationship between the spatial–temporal distribution of the Neolithic cultural sites and the geographic context in the Hanjiang River Basin in the south of Shaanxi Province, China. Archaeological studies have identified 175 Neolithic cultural sites in the study area, with a sequence of Laoguantai (14C age 8–7 ka BP), Yangshao (14C age 7–5 ka BP) and the late period of the Neolithic Age (14C age 5–4 ka BP). The total number of archaeological sites, the distribution area and the density all showed an early ascending and later descending trend, but the proportion of the number of archaeological sites in the study area to the corresponding value of the entire Shaanxi Province declined sharply. Spatially, these sites were concentrated on the terraces of the Hanjiang River and its main tributaries with an altitude of 400–800 m. Multiple data were integrated to clarify the critical effects of tectonic and geomorphologic conditions on the distribution of the Neolithic sites. Further comparisons revealed the correlation of Holocene climate change and environmental evolution with the Neolithic cultural succession in the study area that ameliorated conditions to generally promote the development of the primitive culture while degeneration coincided with the culture's transition or interruption. The discussion on the origin of the primitive culture and the temporal–spatial distribution corresponding to the regional culture differentiation sheds light on the complex and dynamic human–nature interaction system during the Neolithic Age, thus emphasising the wider field-based investigation and high-resolution reconstruction works of the palaeoclimate and palaeoenvironment in the future.  相似文献   

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In summer 1444 the Dauphin Louis, son of Charles VII of France, appeared on the Upper Rhine with a large army. The purpose of his expedition was to reconquer the territories of his future brother-in-law, Sigismund of Austria-Tyrol, from the Swiss Confederates and their allies. However, after achieving just one victory, on 26 August, the Dauphin suddenly agreed to a series of truces and then a peace treaty with the Confederates, even though this made it impossible for him to fulfil his original objective. This article reassesses the contradictory course of the Dauphin's expedition in light of the geopolitical forces that shaped it in the political world of the Upper Rhine. It first analyses the political configuration of the region and the place of the ecclesiastical Council of Basel within it, and then demonstrates that these circumstances combined to force the Dauphin radically to alter his plans in late August 1444. The article also points to the wider implications of the episode for our understanding of later-medieval European politics. Highlighting the inadequacy of national or state-oriented paradigms, it suggests that a new vocabulary is needed to make full sense of the aspects of fifteenth-century political life manifested by the Dauphin's expedition.  相似文献   

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In the early 1970s, there was scarcity in the world grain market, soaring prices and famines in several countries of Asia and Africa. The commercial grain trade was expanded at the expense of food aid. After a brief look at policies addressing the situation in terms of modernised methods of agricultural production for small producers, the article sketches how such policies also affected relief efforts, from the low availability for food aid, the provision of food that was not useful and late deliveries through efforts to tie food aid to local changes in agricultural production and settlement patterns. In part, food aid thus reinforced processes of social differentiation that had contributed to causing the famines in the first place.  相似文献   

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The ‘Movius–Schick hypothesis’ claims that an absence of Levallois (Mode 3) technologies in East Asia is due to the lack of a strong ancestral Acheulean (Mode 2) tradition in that region. Hence, this hypothesis is based on the assumption that similarities between Acheulean handaxes and Levallois cores can be interpreted as being phylogenetically homologous (i.e. due to common technological ancestry) as opposed to being homoplasic (i.e. due to convergent technological evolution). Here, the phylogenetic basis of this hypothesis is tested using a formal cladistic procedure. Under the framework of an ‘iterative’ approach to phylogenetic analysis, a series of post-hoc tests and re-evaluations of results follow the initial cladistic analysis. Results of these combined analyses indicate that morphological similarities between Mode 2 Acheulean handaxes and Mode 3 Levallois cores can, most parsimoniously, be seen as phylogenetically homologous. Hence, these results support the tenets of the ‘Movius–Schick’ hypothesis in suggesting that a lack of Levallois industries in East Asia may be due to the paucity of an ancestral Acheulean tradition in that region. The implications of these phylogenetic analyses for the concept of Palaeolithic ‘Modes’ are discussed. It is further suggested that low demographic levels (i.e. small effective population sizes) in East Asia may have constrained the technological phylogenetic trajectory of East Asia compared with that seen in other regions of the Old World during the Lower Palaeolithic. In addition, it is hoped that several methodological issues discussed here will contribute to the growing field of cultural phylogenetic analysis.  相似文献   

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During the Empire, the population of Rome was composed mostly of lower-class free citizens and slaves. Viewed from historical records, the Roman diet included primarily olives, wine, and wheat, but poor and enslaved Romans may have eaten whatever they were able to find and afford, leading to significant heterogeneity in the Roman diet. Previous carbon and nitrogen isotope analyses of skeletons from Imperial Italy have begun to reveal variation in diet, but little is known about what people ate in the capital city. This study complements previous work by adding new isotope data from human skeletons found in two Imperial-period (1st–3rd centuries AD) cemeteries in Rome. These data suggest that urban and suburban diets differed, most notably in the consumption of the C4 grain millet. Comparing these new data with all published palaeodietary data from Imperial Italy demonstrates that significant variation existed in the diet of the common people.  相似文献   

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At some of the lakes on the mountain plateau Hardangervidda are found the remnants of large stone huts surrounded by middens rich in reindeer bones. On the opposite side of the lakes from these huts a number of cairns making up drift fences indicate that the animals were forced into the water, there to be killed by the hunters.

It appears that the method ‐ which was in use until the Black Death ‐ on the western side of Hardangervidda was known from before the Christian era, whilst on the eastern side it was first introduced in the Early Medieval Period.

The author discusses this variation and relates it to population movements and social change.  相似文献   

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Roc de Marsal has yielded numerous remains of Mousterian occupations, including lithics, fauna and combustion features. It was made famous by the discovery of the skeleton of a Neanderthal child. Given the need to date the sequence, TL and OSL were applied on heated flints and quartz, and OSL on unheated quartz. Chronological results combined with palaeoenvironmental data – faunal remains and micromorphological features in the sediments from the cave, pollen proxies and faunal remains from the region – allowed us to place climate variations in southwest France on a numerical time scale. Denticulate Mousterian occupations were dated to the middle of MIS 4 (65–70 ka) and Quina layers either to the very end of MIS 4 or to MIS 3. Interestingly, a faunal pattern showing a mix of red deer, roe deer and reindeer was found to have occurred during MIS 4, which was shown to be consistent with data from other similar sites in southwest France.  相似文献   

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