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This paper investigates some of the immediate impacts of the Deepwater Horizon oil spill of 2010 on the environment using graphical means. The exploration focuses on the effects of the oil discharge on wildlife, the chemical pollution in the area following the spill, and salinity levels in the aftermath of the spill. Thousands of animals including birds, turtles, dolphins, and whales were found dead along the beaches and in the Gulf of Mexico in the months after the oil discharge. Levels of polycyclic aromatic hydrocarbons were found to be at dangerous levels along the coast line, making conditions for wildlife highly unfavorable. Salinity measurements, which can be used to determine currents and oil movement, are examined over time as well as geographically.  相似文献   
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Central European Journal of Operations Research - We conduct laboratory experiments incorporating different market structures and insiders who compete with imperfectly informed traders. The...  相似文献   
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Holzgrabe U  Brinz D  Kopec S  Weber C  Bitar Y 《Electrophoresis》2006,27(12):2283-2292
CE and related methods are well-established techniques in the analysis of biomolecules, such as DNA and proteins. Even though CE is a rather good alternative to HPLC for the evaluation of the impurity profile and the enantiomeric purity of a drug, it is rarely applied. This might be due to the reservation of national licensing authorities and the pharmacopoeia commissions for several reasons. In this review containing some experimental data we report on several drug examples which demonstrate the superiority of CE over HPLC in special cases, i.e., in the analysis of antibiotics, amino acids and peptides, and the determination of enantiomeric purity. However, in order to make the CE techniques more suitable for pharmacopoeial purposes the general methods describing separation methods have to be complemented with the adjustment of the electrophoretic conditions being necessary to satisfy the system suitability criteria without fundamentally modifying the methods. Taken together CE should be more often applied in drug quality control.  相似文献   
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In this paper, we report the results of molybdenum K-edge X-ray absorption studies performed on the oxidized and reduced active sites of the sulfite dehydrogenase from Starkeya novella. Our results provide the first direct structural information on the active site of the oxidized form of this enzyme and confirm the conclusions derived from protein crystallography that the molybdenum coordination is analogous to that of the sulfite oxidases. The molybdenum atom of the oxidized enzyme is bound by two Mo=O ligands at 1.73 A and three thiolate Mo-S ligands at 2.42 A, whereas the reduced enzyme has one oxo at 1.74 A, one long oxygen at 2.19 A (characteristic of Mo-OH2), and three Mo-S ligands at 2.40 A.  相似文献   
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