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191.
Ethno‐territoriality is an increasingly invoked term by those doing research on nationalism and ethnic conflict. Despite this, it has not been subject to detailed definitional and conceptual examination. This article develops a conceptual framework for thinking about ethno‐territoriality and ethnic conflict. It begins by briefly describing the relationship between territoriality, state sovereignty, and nationalist politics. I then provide a definition of ethno‐territoriality and outline a four‐part typology of the key elements of ethno‐territorial practice. Following this I discuss the role that ethno‐territoriality plays in the making of ethnic conflict.  相似文献   
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193.
This paper presents a case study of a cluster of tornadoes produced by tropical cyclone (TC) Ivan in the Mid-Atlantic region of the United States on 17–18 September 2004. Ivan produced 118 tornadoes between 15 and 18 September, but 57 of these occurred in a period of only 10 h on the last two days. The number of tornadoes that occurred in this event is anomalous when compared to regional tornado climatology and to other TC tornado events. Furthermore, a significantly large number of the tornadoes, when compared to other TC tornadoes, were rated strong according to the Fujita Scale, and they were anomalously long- and wide-tracked. Ivan was in a synoptically favorable environment when these tornadoes were produced, and the tornadoes occurred in a favorable local-scale environment near a front with spatially overlapping shear and buoyancy.  相似文献   
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195.
The absorption spectrum of Sii in the wavelength region 1500–1900 Å has been photographed at high resolution. The silicon vapour was produced in a 122 cm long King furnace at 1800–2300°C. Forty-two Rydberg series have been observed from the ground state terms 3p 2 3 P and1 D to terms associated with the 3pns and 3pnd configurations. All of the series from these configurations withJ<4 have been extended with the 3pnd 3 D 3 o levels reachingn=56. Numerous perturbations have been observed. This laboratory work has provided the basis for extending the identification of silicon lines in the solar spectrum. Nearly all lines found in the laboratory spectrum are also found in rocket spectrograms of the solar chromosphere. More than 300 lines have been attributed to Sii. The excellent correlation between laboratory and solar Sii lines will be illustrated.  相似文献   
196.
Apparently, there are two types of size-frequency distributions of small lunar craters (1–100 m across): (1) crater production distributions for which the cumulative frequency of craters is an inverse function of diameter to power near 2.8, and (2) steady-state distributions for which the cumulative frequency of craters is inversely proportional to the square of their diameters. According to theory, cumulative frequencies of craters in each morphologic category within the steady-state should also be an inverse function of the square of their diameters. Some data on frequency distribution of craters by morphologic types are approximately consistent with theory, whereas other data are inconsistent with theory.A flux of crater producing objects can be inferred from size-frequency distributions of small craters on the flanks and ejecta of craters of known age. Crater frequency distributions and data on the craters Tycho, North Ray, Cone, and South Ray, when compared with the flux of objects measured by the Apollo Passive Seismometer, suggest that the flux of objects has been relatively constant over the last 100 m.y. (within 1/3 to 3 times of the flux estimated for Tycho).Steady-state frequency distributions for craters in several morphologic categories formed the basis for estimating the relative ages of craters and surfaces in a system used during the Apollo landing site mapping program of the U.S. Geological Survey. The relative ages in this system are converted to model absolute ages that have a rather broad range of values. The range of values of the absolute ages are between about 1/3 to 3 times the assigned model absolute age.  相似文献   
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198.
Certain polycyclic aromatic hydrocarbons and phenobarbital induced an increase in the activity of microsomal NADPH neotetrazolium reductase (linked to mixed function oxygenase systems) in the blood cells of Mytilus edulis. Phenanthrene and methylated naphthalenes caused lysosomal destabilisation which is believed to be directly related to the mechanism of cytotoxicity in the digestive cells. The use of these cytochemical techniques as indices of aromatic hydrocarbon contamination is discussed.  相似文献   
199.
Studies were performed on the common mussel, M. edulis L., to determine whether copper (Cu) exposure can affect the extent to which digestive cell proteins are oxidised and whether such oxidative damage is mediated by free radicals. Three age groups of mussels were exposed for 6 -days to environmentally realistic concentrations of Cu and then digestive gland homogenates were examined for evidence of protein carbonyl formation. Significant increases in carbonyls relative to untreated control mussels were seen for the youngest (2–4 year-old) and oldest (≥ 10 year-old) mussels only after exposure for 6 days, followed by recovery from exposure for a further 6 days. Untreated mussels also showed an age-related difference in protein oxidation, with a significantly lower concentration in the youngest animals (2–4 year olds). Copper did not affect the levels of modified tryptophan or tyrosine residues or the extent of total lipid peroxidation in digestive gland homogenate. Significant depletion of total vitamin E (a-tocopherol) was seen only in young and medium-aged mussels following exposure for 6 days. The levels of protein carbonyl groups were increased in digestive cell cytosol and lighter lysosomes but not in heavier lysosomes or digestive gland microsomes following 5 days exposure to Cu. Dihydrohodamine-123 was converted to fluorescent rhodamine-123 following sequestration into digestive cell lysosomes. The results suggest a link between the lysosomal sequestration of copper, a concomitant increase in the production of oxyradicals and the potential for intracellular oxidative damage, as well as an increased capacity for oxidative damage in older animals.  相似文献   
200.
Multichannel seismic reflection profiles across the Sunda Trench slope off central Sumatra reveal details of subduction zone structure. Normal faults formed on the outer ridge of the trench offset deep strate and the oceanic crust, but die out upsection under the trench sediments. At the base of the inner trench slope, shallow reflectors are tilted seaward, while deeper reflectors dip landward parallel to the underlying oceanic crustal reflector. Intermediate depth reflectors can be traced landward through a seaward-dipping monocline. We interpret this fold as the shallow expression of a landward-dipping thrust fault at depth. Landward of this flexure, relatively undeformed strata have been stripped off the oceanic plate, uplifted 700 meters, and accreted to the base of the slope. The oceanic crust is not involved in the deformation at the toe of the slope, and it can be observed dipping landward about 25 km under the toe of the accretionary prism.The middle portion of the trench slope is underlain by deformed accreted strata. Shallow reflectors define anticlinal structures, but coherent deep reflectors are lacking. Reflectors 45 to 55 km landward of the base of the slope dip 4°-5° landward beneath a steep slope, suggesting structural imbrication.A significant sediment apron is absent from the trench slope. Instead, slope basins are developed in 375–1500 m water depths, with an especially large one at about 1500 m water depth that is filled with more than 1.1 seconds of relatively undeformed sediments. The seaward flank of the basin has recently been uplifted, as indicated by shallow landward-dipping reflectors. Earlier periods of uplift also appear to have coincided with sedimentation in this basin, as indicated by numerous angular unconformities in the basin strata.Contribution of the Scripps Institution of Oceanography, new series.  相似文献   
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