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Oil spill detection by satellite remote sensing   总被引:13,自引:0,他引:13  
This paper presents the state of the art for oil spill detection in the world oceans. We discuss different satellite sensors and oil spill detectability under varying conditions. In particular, we concentrate on the use of manual and automatic approaches to discriminate between oil slicks and look-alikes based on pattern recognition. We conclude with a discussion of suggestions for further research with respect to oil spill detection systems.  相似文献   
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Oil Spill Detection in Radarsat and Envisat SAR Images   总被引:8,自引:0,他引:8  
We present algorithms for automatic detection of oil spills in synthetic aperture radar (SAR) images. The algorithms consist of three main parts, namely: 1) detection of dark spots; 2) feature extraction from the dark spot candidates; and 3) classification of dark spots as oil spills or look-alikes. The algorithms have been trained on a large number of Radarsat and Envisat Advanced Synthetic Aperture Radar (ASAR) images. The performance of the algorithm is compared to manual and semiautomatic approaches in a benchmark study using 59 Radarsat and Envisat images. The algorithms can be considered to be a good alternative to manual inspection when large ocean areas are to be inspected  相似文献   
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In the past, interleukin-8 (IL-8) could be demonstrated within keratinocytes in normal epidermis and inflammatory skin diseases, like psoriasis and eczema. Using monoclonal antibodies, the distribution of IL-8 immunoreactivity was inversely related to the density of inflammatory infiltrate. Other in vitro observations indicated IL-8 to be a growth factor for keratinocytes. These results prompted an immunohistochemical examination of IL-8 immunoreactivity in malignant and semimalignant epithelial tumours of human skin. Whereas IL-8 could not be detected within the transformed cells of epithelial tumours or melanoma, some tumour cells within well differentiated squamous cell carcinoma and Bowen's disease showed IL-8 immunoreactivity. Thus, loss of IL-8 immunoreactivity can be a sign of malignant transformation. This indicates an important role in growth regulation as well as terminal differentiation of human keratinocytes.  相似文献   
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With long-term ionosonde records from 1947 to 2001 at Chong-qing, China, we show long-term trends of the ionospheric parameters, the critical frequencies of E-layer foE, F1-layer foF1 and F2-layer foF2, the E-layer height h'E, and the F2-layer peak height hmF2, respectively. Using an approach of discrete wavelet decomposition arithmetic, we have got the long-term components in the variations of the iono spheric parameters. It does exist nearly linear long-term decreasing trends of above ionospheric parameters from 1947 to 1990, then a nearly linear increase from 1990 to 2001. The decreases are approximately by 0. 35MHz, 0. 4MHz, 2MHz,20km, respectively, for foE, foF1, foF2 and hmF2, but increase by 4km for h'E,from 1947 to 1990. Simultaneously, we find similar long-term trends in the variations of 10.7cm solar radio flux and in sunspot number. The long-term components of the ionospheric parameters have extremely high correlation with those of 10.7cm solar radio flux and sunspot number. This implies that solar activities are the control factor of the long-term trends of the ionosphere. We confirm above conclusions with results from the long-term data at Slough station, UK.  相似文献   
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This article discusses anatomy and normal biomechanics of the lesser digits. The pathomechanics that may lead to digital deformities or the hammered digit syndrome are discussed also. The importance of identifying the causes of the hammered digit syndrome prior to surgical correction is emphasized. Knowing the causes can help determine effective postoperative control that can neutralize the deforming forces.  相似文献   
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In this paper we describe the construction of mouse-human IgG3 mutant antibodies resembling IgG1 in their disulfide bond pattern between the heavy and light chain (H-L) and between the two heavy chains (H-H). The effector functions of these mutant antibodies were compared to normal IgG3 and IgG1. Changing only the disulfide bond pattern between the heavy and light chains did not alter the ability to induce complement mediated cell lysis (CML), regardless of the amount of corresponding antigen that had been introduced to the surface of the target cells. However, alteration of the disulfide bond pattern between the two heavy chains had a large effect on CML due to shortening of the hinge from 62 to 15 amino acids. No difference between the mutants and normal antibodies in antibody-dependent cell-mediated cytotoxicity (ADCC) was observed. This suggests that IgG3 can adopt the H-L disulfide bond pattern of IgG1 without obtaining the CML activity characteristic for IgG1.  相似文献   
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The high-affinity IgG receptor, Fcgamma receptor I (FcgammaRI), is expressed exclusively on myeloid cells, and there is a great interest in the targeting of vaccine antigens to FcgammaRI using anti-human FcgammaRI antibodies or fragments derived from such molecules. In order to reduce the size and complexity of the targeting reagent, we have searched for FcgammaRI binding peptides in peptide libraries displayed on phage. The human monocytic cell line U937 was used as target. Phages that displayed the consensus peptide CLRSGXGC were selected and revealed increased binding to IFN-gamma stimulated versus non-stimulated U937 cells as well as to FcgammaRI transfected versus non-transfected IIA1.6 cells. Furthermore, they bound the extracellular domains of soluble FcgammaRI, but neither FcgammaRIIA, FcgammaRIIB nor FcgammaRIIIB. Binding was inhibited by a synthetic version of the peptide, whereas neither human IgG nor the FcgammaRI-specific monoclonal antibodies (mAb) mAb22 and 32.2 interfered. Flow-cytometry analysis and internalization studies showed that a synthetic biotin-conjugated peptide ADGACLRSGRGCGAAK-bio was able to target U937 cells and FcgammaRI transfected IIA1.6 cells, and further to promote internalization and vesicular degradation of streptavidin coupled to 1 microm magnetic beads. These peptides may have potential as FcgammaRI targeting reagents.  相似文献   
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