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With proximal and distal obstruction to the lacrimal drainage system, mucus accumulates forming a cyst. In order to diagnose a nasolacrimal duct cyst antenatally, the sonographer must image the region adjacent to the orbits. 相似文献
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Synthesis and spatial dynamics of socio-economic metabolism and land use change of Taipei Metropolitan Region 总被引:3,自引:0,他引:3
Ever since the concept of metabolism was extended from biological science by social scientists to analyze human systems, socio-economic metabolism has been extensively applied to explore resource consumption, asset accumulation, waste emissions, and complex processes of land use change in a socio-economic system. Current research in socio-economic metabolism and land use change has used accounting approaches for macroscopic comparisons of countries and regions. However, socio-economic metabolism has seldom been applied to the analysis of land use change. To simulate the spatial-temporal dynamics of socio-economic metabolism and land use change, this study adopts a spatial system modeling method to develop a Socio-Economic Metabolism and Land Use Change (SEMLUC) model for the Taipei Metropolitan Region. The simulation results illustrate that the Taipei Metropolitan Region is highly dependent on inflows of non-renewable energy and exhibits a spatial hierarchy of non-renewable energy consumption centering on Taipei's Main station. Additionally, urban assets provide feedback to natural and agricultural systems to extract additional resource inflows which, driven by the maximum power principle, accelerate the convergence of energy flows toward urban assets. Accumulating urban assets also facilitates inflows of non-renewable material to nearby cells thereby enhancing land use conversion to urban areas. This work also demonstrates the capability of ArcGIS software in simulating socio-economic metabolism and land use change in an urban system. 相似文献
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Mangrove trees planted for restoration or rehabilitation often fail to show satisfactory survivals. Although it is generally
assumed that barnacle fouling is a factor in mangrove mortality, the sub-lethal response of mangroves to this fouling is not
known. In the present study, we compare the leaf morphology (stomata density, leaf thickness, percentage thickness of palisade
layer and number of hypodermal layers), lenticel density and the plant fitness (number of flowers or droppers per tree) between
mangroves fouled by the acorn barnacle Fistulobalanus albicostatus (the fouled group, number of barnacles ~ 120 individuals per tree) and non-fouled mangroves (the control group). We observed
55 Kandelia obovata from three locations, two in Hong Kong (n = 35, fouled 25 and control 10) and one location in Taiwan (n = 20, fouled 10 and control 10). Aegiceras corniculatum (n = 45) was observed from two sites in Hong Kong, one on the east coast (n = 20, 10/10) and one on the west coast (n = 25, 10/15). In seedlings (K. obovata
n = 10, 5/5), fouling density did not affect leaf morphology. In mature trees, however, leaves from fouled trees had significantly
higher density of stomata and stem lenticel, a lower percentage thickness of leaf palisade layer and more layers of lower
hypodermis in the leaves, probably for compensating the impeded gaseous exchange functions of the lenticels. The number of
droppers and flowers on fouled mangroves was significantly lower. It is possible that after compensating for respiratory stress,
the plant had less energy available for reproduction. Although there was no obvious barnacle-induced mortality in this study,
barnacles appear to be related to a reduction in plant fitness. This may induce sufficient stress that over time fouled mangroves
cannot sustain viable populations. 相似文献