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A method is presented for elevation, latitude and longitude decorrelation stretch of multi-temporal MODIS MYD11C3 imagery (monthly average night land surface temperature (LST) across USA and Mexico). Multiple linear regression analysis of principal components images (PCAs) quantifies the variance explained by elevation (H), latitude (LAT), and longitude (LON). The multi-temporal LST imagery is reconstructed from the residual images and selected PCAs by taking into account the portion of variance that is not related to H, LAT, LON. The reconstructed imagery presents the magnitude the standardized LST value per pixel deviates from the H, LAT, LON predicted. LST anomaly is defined as a region that presents either positive or negative reconstructed LST value. The environmental assessment of USA indicated that only for the 25 % of the study area (Mississippi drainage basin), the LST is predicted by the H, LAT, LON. Regions with milled climatic pattern were identified in the West Coast while the coldest climatic pattern is observed for Mid USA. Positive season invariant LST anomalies are identified in SW (Arizona, Sierra Nevada, etc.) and NE USA.  相似文献   
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On the basis of a systematic testwork with a number of different dusts, the explosion indices as determined within the 20 l sphere and with the ISO-VDI 1 m3 vessel have been compared. The repeatability has been assessed and since some systematic deviations appear a refined physical analysis of the explosion processes is developed. It appears in particular that the cube root law supposed to link both vessels is not verified. A striking illustration of this appears when a dust with a significant explosion severity inside the 20 l sphere is not even explosible in the larger vessel. It is strongly suggested that the ignition energy is forcing very significantly the explosion in the smaller vessel inducing several tens of Celsius degrees of preheating. It is shown also that the inner level of turbulence is decreasing very fast in the 20 l sphere during the flame development so that difficult-to-ignite mixtures would tend to burn at a lower combustion rate. It is further demonstrated that the major bias between the chambers can be explained and quantified with these elements. A correlation with the standard 1 m3 vessel and a grid of interpretation of the data is proposed.  相似文献   
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The viral contamination of sea-water at different depths and in the sediments in the area near the discharge of treated domestic sewage, was investigated. The isolation frequency of viral particles was low: on 19 samples of sea-water, 4 are positive and on 6 samples of sediment, 1 is positive. Viral concentrations were not substantial: they varied from 2,9 to 5,9 Most Probable Number Cytopathic Unit (M.P.N.C.U.) in 500 ml of sea-water or in 500 g of sediment. No homogeneous distribution of viral particles in sea-water was observed.  相似文献   
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The distribution between sea water and sediment of a polio virus has been studied under an experimental system. Throughout 7 days of incubation, a significant statistical difference exist between the viral concentration of sea water in times T0 and T7 (P~0,99) and the viral concentration of sea water samples and sediments in times T7 (P~0,95). this for any type of sediment.  相似文献   
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S-100 protein, which is found essentially in the astrocytes of the nervous system, was assayed in amniotic fluids by Particle Counting Immuno Assay. It was present in 19 cases of anencephaly out of 26, in 1 case of open spina bifida out of 5 and in each of the 4 cases of fetal death, whereas it was not detected in the 48 control amniotic fluids collected between the 16th and the 35th week of gestation. Thirty-one amniotic fluids from fetuses with other congenital malformations were devoid of detectable S-100. The presence of S-100 in amniotic fluid of anencephalic fetuses can presumably be considered as a biological sign of necrosis of the exencephalic brain and seems specific to damage of the central nervous system accompanied by neural tube defect.  相似文献   
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