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Palestinian suicide terrorism has been a key feature in the latest phase of the Israeli–Palestinian conflict. During the past decade, and particularly since September 2000, there has been a substantial increase in the use of this type of warfare. Recent studies suggest that, contrary to common belief, suicide terrorism is highly rational and driven by strategic considerations. This article explores the rationality of Palestinian suicide terrorism from a geographical perspective. It is argued that suicide terrorism works along two parallel paths: rationality and randomness. It complies with geographical fundamentals, and target selection is highly rational, subject to spatial considerations such as distance, agglomeration, and accessibility. As the permeability to Israel became more difficult, suicide bombers and their organizers had to adopt more flexible practices which emphasized other spatial considerations. Timing is of importance both for strategic and tactical reasoning. Obstructing negotiations and peace talks has been a salient objective, but the exact timing of suicide bombings has been influenced by tactical considerations, which aim at maximizing casualties. 相似文献
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Despite the growing recognition that metropolitan real estate markets are segmented spatially and that property development is still profoundly local, research has taken little notice of agents that actually initiate and propel the development process. Earlier studies that aimed at identifying metropolitan segmentation employed statistical techniques whilst ignoring the practices of agents that might shed light on the notion of segmentation. Greater Toronto’s office market, which is Canada’s largest, exemplifies a real estate market far more spatially segmented than the downtown–suburban framework, a dichotomy so extensively use in research. Locational preferences of the numerous developers that work in this market tend to be highly localized, confirming deep-rooted segmentation. Their preferences correspond to submarket classification and follow dividing lines that crisscross the metropolitan region, emphasizing the extent and the power of parochialism, which defines the nature of real estate development. 相似文献
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This study analyzes metropolitan dynamics in a small country with an “island state” context of closed boundaries, using commuting data and mobile phone tracking data. We examine whether the Israeli context encourages the formation of a monocentric “metropolitan state,” characterized by increasing links between localities throughout the country and its principal metropolitan node (Tel Aviv)—rather than with secondary metropolitan areas—and by fuzzy, overlapping metropolitan boundaries. Commuting data from the 1995 and 2008 censuses show that metropolitan expansion processes in Israel are gradual. Mobile phone tracking data for 2013 reveal similar patterns, confirming the urban structure’s stability and the reliability of tracking data as a means of assessing metropolitan processes. The “island state” context supports growing monocentricity, but, when it comes to commuting and travel for other purposes, Israel is not yet a metropolitan state; metropolitan boundaries are not as fuzzy and rapidly changing as expected. 相似文献
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Natural Hazards - Risk and resilience assessments have been both widely, but separately, used as tools for guiding policymakers to formulate disaster-risk reduction policies. On the one hand, risk... 相似文献
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Coral branches partially block the flow of water through the colony, creating an inner zone of reduced water exchange where hypoxic conditions can develop during the night. Previous studies have shown that this oxygen deficiency is alleviated by the fanning behavior of mutualistic damselfish that spend the night between the coral branches, constantly moving their fins. Our findings show that fin‐stroking frequency during fanning by the damselfish Dascyllus marginatus is moderately plastic, with lower frequency under higher oxygen concentration, and vice versa. The inter‐play between oxygen concentration and fin motion maintains nearly steady oxygen concentration between the coral branches during the night. 相似文献
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Oxytetracycline (OTC) is an antibiotic that is regularly added to fish ponds used in industrial- scale fish-farming along
the Mediterranean coast of Israel. It is not found in unpolluted water. The ponds are constructed upon porous sands that are
also the host rock of the local aquifer. These ponds leak. Monitoring for OTC was carried out in a fish pond and three surrounding
water wells that exploit the local aquifer. The local groundwater is composed of the native groundwater and the leakage additions.
Two wells, P-204 P-205 are used to insure that the water levels in the ponds are maintained. A frequently pumping well, M-2,
is located closest to the main source of OTC input at pond B. It is used to supply drinking water and OTC was found in it.
This contaminant is related to leakage from the nearby fish pond. OTC is generally assumed to be immobile and effectively
removed by soil and sediments. In this case, continuous leakage of the pond has created preferential saturated flow paths
that bring the contaminants directly to groundwater, bypassing the immobilizing sorption processes that usually take place
in the unsaturated zone. In the absence of such conduits OTC is effectively excluded from reaching other producing wells. 相似文献
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Alexander Tsatskin Tatyana S.Gendler Friedrich Heller Igal Dekman Gitti L.Frey 《山地科学学报》2009,6(2):113-124
The paper addresses the controversial question of the role of clay-sized dust in the formation of paleosols in coastal eolianites, Israel. At the Habonim type section, the pedocomplex dated by archaeology and luminescence to 45-135 ka ago shows at least three paleosols, not separated by non-soil sediments. The oldest reddish paleosol （apparently related to MIS 5） is magnetically enhanced, leached from carbonates, with signs of bioturbation and strongly aged clay coatings. The reddening is due to very fine, -20 nm, poorly crystallized, superparamagnetic （SP） hematite, as determined by Mossbauer studies. In subsoil, lithorelics of eolianite are found. Over time, the soil surface aggraded due to accelerated fine dust accumulation alongside local slope wash. On younger materials formed magnetically depleted vertisols, dominated by smectite-type expandable paramagnetic clays. In thin sections, vertisols exhibit strong stipple-speckled and striated b-fabric due to shrink-swell processes, impregnative calcite nodules and Fe-Mn redistribution. The uppermost hydric vertisol shows the strongest expression of juxtaposed features of recurrent calcite and Fe precipitation. This paleosol developed on colluvial soil materials, as evidenced by mixing of clay coated and uncoated grains of quartz and calcite allochems. M6ssbauer spectra show high amounts of Fe（III） incorporated in the clay structure, low amounts of SP goethite and absence of SP hematite. Whilst magnetic susceptibility drops in vertisols to minimal values, increase. The latter along ferrimagnetie grain sizes with differences in the hierarchy of microfabric features is taken as indication for lithologic discontinuities which may have resulted from continuous, albeit variable and low-intensity, input of eolian clay from both remote Saharan and local sources, roughly dated to the earlier to middle part of the Last Glacial. 相似文献
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Igal Charney 《Area》2007,39(2):195-205
After 2000 a handful of very tall buildings were approved in central London, a circumstance that challenged well-established planning practices in that part of the city. Their promotion by Ken Livingstone, the mayor, but opposition to them by conservation groups, seemed to signal a fierce campaign ahead; in fact, it was all over in an instant. This article examines how this debate was framed to dismiss the arguments and concerns of those who oppose tall buildings. To make tall buildings acceptable, London's mayor drew on the merits associated with iconic architecture and high-profile architects. Under Livingstone's incumbency tall buildings were affirmed by the expertise and clout of global architects who provided legitimacy for mayoral ambitions to reach for the sky. Stressing the significance of high-quality design and iconic architecture helped to wear down deep-rooted antagonism and to channel the debate to improving the aesthetic qualities of London, a goal that enjoys wide consensus. 相似文献
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