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MICHAEL MATSON GEORGE STEPHENS JENNIFER ROBINSON 《International journal of remote sensing》2013,34(7):961-970
Abstract Due to increased concern over the climatic and economic impact of fires associated with deforestation and seasonal burning, most of which occurs in remote parts of the worid, it is necessary to find ways to effectively monitor such activity. The 3.8μm channel on board the National Oceanic and Atmospheric Administration's polar-orbiting satellites is very sensitive to high temperature sources such as fires. Case studies in Mexico, Brazil, Mozambique and the Soviet Union have been selected to demonstrate the utility of this channel for fire detection. With the fire detection capability of the 3.8 μm channel and the daily global coverage, it is possible to monitor world-wide fire activity. 相似文献
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ALAIN ROYER USE CHARBONNEAU RICHARD BROCHU JENNIFER M. MURPHY PHILIPPE M. TEILLET 《International journal of remote sensing》2013,34(4):579-591
Abstract This paper analyses the radiometric accuracy of LANDSAT-5 Thematic Mapper (TM) data and of LANDSAT-5 Multispectral Scanner (MSS) data, using concurrent TM and MSS images recorded simultaneously over the city of Montreal, Quebec, Canada. The data sets were obtained from the Canada Centre for Remote Sensing (CCRS), and have been preprocessed for geometric correction, and for radiometric 23calibration utilizing the in-flight calibration lamp data. The comparison of the TM and MSS normalized apparent reflectances computed for 12 different typical cover types using the post-launch calibration dynamic ranges shows the relevance of the CCRS processing systems. The significant linear regressions, obtained between channels from the two sensors, and the analysis of the ground reflectance corrected for atmospheric absorption and scattering as well as for pixel adjacency effects, can serve both to assess detector degradation with time and to rescale data to match those from other LANDSAT sensors. 相似文献
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ZEYNEP GUZEL‐SEYDIM JENNIFER T WYFFELS ATIF C SEYDIM ANNEL K GREENE 《International Journal of Dairy Technology》2005,58(1):25-29
Microbial populations in kefir and kefir grains were enumerated by plating. Total lactic acid bacteria, lactoccocci, lactobacilli and yeast populations increased during fermentation and increased slightly during cold storage. Kefir grains had a lactic acid bacteria : yeast ratio of 10 9 : 10 6 . In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods, which indicated yeast colonization on the surface and middle part of the kefir grain. Three types of lactobacilli (short, long and curved) were noted throughout the grain. Lactococci were not observed under SEM; preparation of kefir grains for SEM may have caused removal of lactococci from the grains. 相似文献
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INTROGRESSING PHEROMONE QTL BETWEEN SPECIES: TOWARDS AN EVOLUTIONARY UNDERSTANDING OF DIFFERENTIATION IN SEXUAL COMMUNICATION 总被引:2,自引:0,他引:2
Groot AT Ward C Wang J Pokrzywa A O'Brien J Bennett J Kelly J Santangelo RG Schal C Gould F 《Journal of chemical ecology》2004,30(12):2495-2514
As a first step toward understanding how noctuid moths evolve species-specific pheromone communication systems, we hybridized and backcrossed two closely related moth species, Heliothis virescens (Hv) and H. subflexa (Hs), which differ qualitatively and quantitatively in their multi-component sex pheromone blends. We used amplified fragment length polymorphism (AFLP) marker-based mapping of backcross families to determine which of the 30 autosomes in these moths contained quantitative trait loci (QTL) controlling the percentages of specific chemical components in the pheromone blends. In two previous backcrosses to Hs, we found a strong depressive effect of Hv-chromosome 22 on the percentage of three acetate components in the pheromone gland. These acetates are present in Hs and absent in Hv. Here, we describe how we introgressed Hv-chromosome 22 into the genomic background of Hs. Selection for Hv-chromosome 22 started from backcross 3 (BC3) females. All females that had Hv-chromosome 22 and a low percentage of acetates (< 3% of the total amount of pheromone components present) were backcrossed to Hs males. In BC5 to BC8, we determined whether Hv-chromosome 22 was present by a) running only the primer pairs that would yield the markers for that chromosome, and/or b) determining the relative percentages of acetates in the pheromone glands. Either or both genotype and phenotype were used as a criterion to continue to backcross these females to Hs males. In BC9, we confirmed the isolation of Hv-chromosome 22 in the Hs genomic background, and backcrossed the males to Hs females to eliminate the Hv-sex chromosome as well as mitochondrial DNA. The pheromone composition was determined in BC3, BC5, and BC11 females with and without Hv-chromosome 22. All backcross females with Hv-chromosome 22 contained significantly less acetates than females without this chromosome. In addition, BC3 females with Hv-chromosome 22 contained significantly more Z11-16:OH than BC3 females without Hv-chromosome 22. However, in BC5 and BC11 females, the correlation between Z11-16:OH and Hv-chromosome 22 was lost, suggesting that there are separate QTL for the acetates and for Z11-16:OH, and that the relative amount of the alcohol component is only affected in epistasis with other (minor) QTL. Now that we have succeeded in isolating the chromosome that has a major effect on acetate production, we can test in behavioral experiments whether the presence of acetates may have been a driving force for a shift in pheromone composition. Such tests are necessary to move towards an evolutionary understanding of the differentiation in sexual communication in Heliothis spp. moths. 相似文献
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JENNIFER A STILLMAN 《Journal of food science》1993,58(4):810-812
The influence of color on flavor was investigated using 310 untrained volunteers who each judged the flavor of 1 of 8 beverages. Artificially flavored raspberry and orange beverages were either left uncolored, or colored red, orange, or green. Color had a significant influence on the identification of both flavors, although every combination of color and flavor was identified correctly beyond the level expected by chance. Performance was degraded equally when beverages were uncolored, and facilitated equally when beverages were appropriately colored. Unusual color-flavor combinations reduced the identification of raspberry flavor more than that of orange flavor. The influence of color was particularly salient because tasters were aware that the color of the beverage might be inappropriate to its flavor. 相似文献
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ROBERT D. PLOTNICK JENNIFER ROMICH JENNIFER THACKER MATTHEW DUNBAR 《Journal of Urban Affairs》2011,33(3):345-366
ABSTRACT: This study contributes to the debate about tolls’ equity impacts by examining the potential economic costs of tolling for low‐income and non‐low‐income households. Using data from the Puget Sound metropolitan region in Washington State and geographic information systems methods to map driving routes from home to work, we examine car ownership and transportation patterns among low‐income and non‐low‐income households. We follow standard practice of estimating tolls’ potential impact only on households with workers who would drive on tolled and nontolled facilities. We then redo the analysis including broader groups of households. We find that the degree of regressivity is quite sensitive to the set of households included in the analysis. The results suggest that distributional analyses of tolls should estimate impacts on all households in the relevant region in addition to impacts on just users of roads that are currently tolled or likely to be tolled. 相似文献
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Volatile Components of an Unflavored Textured Soy Protein 总被引:2,自引:0,他引:2
Aroma volatiles of textured soy protein (TSP) were extracted and concentrated to a valid isolate using established techniques. By GC-MS mainly, 146 positive identifications and 26 partial characterizations were made. The majority have not been published previously as volatiles of TSP or relevant raw materials (raw soybeans, flakes, flours, concentrates, isolates). Some are probably natural soybean metabolites - β-damascenone and bovolide being reported here for the first time in soy. Many result from lipid oxidation/degradation and from heating sugars and/or amino acids. However, carotenoid degradation and aromatic ring fusion are also indicated, and could play a hitherto undetermined role in soy processing technology. 相似文献