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Studies done on adults reveal a significant role of fibrinogen (FG) in cardiovascular disease. The main purpose of our study was to determine the level of plasma FG in children, its distribution according to age and sex, and its relationship to other cardiovascular risk factors such as cigarette smoking, plasma lipid disturbances, and a positive family history for other cardiovascular risk factors. We studied a population of 2224 children, aged 2 to 18 years, from five different schools located in Madrid. We found a significantly higher level of FG in the groups of females aged 6 to 8 and 16 to 18 years than in males of the same ages (p < 0.001). The study population was distributed into two groups according to the plasma fibrinogen level: > 394 mg/dl and < 394 mg/dl. In both groups we determined plasma levels of total cholesterol, triglycerides, and very low-density lipoprotein (VLDL) cholesterol and found these parameters significantly higher in the group with an FG level > 394 mg/dl (p < 0.05).  相似文献   
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We propose a slight modification of the Berlekamp-Massey Algorithm for obtaining the minimal polynomial of a given linearly recurrent sequence. Such a modification enables to explain it in a simpler way and to adapt it to lazy evaluation. partially supported by the Galois Theory and Explicit Methods in Arithmetic Project HPRN-CT-2000-00114 partially supported by the European Union funded project RAAG CT-2001-00271  相似文献   
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Landsat 8 is the first Earth observation satellite with sufficient radiometric and spatial resolution to allow global mapping of lake CDOM and DOC (coloured dissolved organic matter and dissolved organic carbon, respectively) content. Landsat 8 is a multispectral sensor however, the number of potentially usable band ratios, or more sophisticated indices, is limited. In order to test the suitability of the ratio most commonly used in lake carbon content mapping, the green–red band ratio, we carried out fieldwork in Estonian and Brazilian lakes. Several atmospheric correction methods were also tested in order to use image data where the image-to-image variability due to illumination conditions would be minimal. None of the four atmospheric correction methods tested, produced reflectance spectra that matched well with in situ measured reflectance. Nevertheless, the green–red band ratio calculated from the reflectance data was in correlation with measured CDOM values. In situ data show that there is a strong correlation between CDOM and DOC concentrations in Estonian and Brazilian lakes. Thus, mapping the global CDOM and DOC content from Landsat 8 is plausible but more data from different parts of the world are needed before decisions can be made about the accuracy of such global estimation.  相似文献   
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The transitional areas that lie between wildlands and urbanized spaces, generally defined as wildland–urban interfaces (WUI), represent an increasing risk factor in Mediterranean areas; these define a new scenario in forest fire fighting and prevention. We have developed a methodological approach in order to assess the hazard and vulnerability of WUI which is based on landscape analysis, on the use of Geographic Information Systems (GIS) techniques and remote sensing. Unlike traditional approaches which are based on local scale characterization of WUI, we propose a progressive multi-scale approach. In order to reach an operative classification of the WUI the methodology was developed in three stages: a regional urban development model, a landscape character assessment and finally, a WUI typology. The last WUI typology has been based on the identification of different urban morphologies and their context within the type of landscape in which they occur.  相似文献   
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