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131.
Escherichia coli distribution and persistence in nearshore Lake Michigan were assessed following heavy rains and sanitary sewer overflow (SSO) and combined sewer overflow (CSO) events over a 5-year period, including an 18-day period following 25.4 cm of rainfall in which intensive studies were conducted following multiple CSO and SSO events. E. coli levels in the Milwaukee estuary and harbor following SSO and CSO events ranged from 104 to nearly 105 CFU/100 mL, which were significantly higher (p ≤ 0.05) than levels following rainfall alone. Sites outside of the breakwall but within the contamination plume (e.g., within 2 km of the harbor) were an order of magnitude lower. Locations 2–5 km from the harbor ranged from below detection limits, of < 1 to 5 CFU/100 mL. E. coli levels corrected for dilution based on specific conductivity measurements were lower than what would be expected for loss due to dilution alone, suggesting a combination of die-off and dilution, were responsible for the rapid disappearance of these organisms outside of the harbor. E. coli and fecal coliforms measured concurrently demonstrated that fecal coliforms could be recovered longer than E. coli in the open waters of the lake. E. coli isolated directly from sewage treatment plant influent were found to have a marked increase in antibiotic resistance traits for ten antibiotics commonly used in the human population compared with isolates from two animal sources of fecal pollution. However, E. coli obtained from sewage impacted water (n = 2,513) and from stormwater impacted water (n = 1,465) collected the previous year when there were no sewage overflows, were found to have no significant difference (p < 0.05) in the frequency of resistance when comparing the two conditions. E. coli survival characteristics and population dynamics are most likely influenced by multiple factors in complex systems such as the watershed/estuarine/lake environments of the Great Lakes.  相似文献   
132.
The status of invasive dreissenid mussels (Dreissena polymorpha and D. bugensis) and native amphipods (Diporeia spp.) in Lake Ontario was assessed in 2003 and compared with historical data. D. polymorpha (zebra mussels) were rarely observed in 2003, having been displaced by D. bugensis (quagga mussels). D. bugensis expanded its depth range from 38 m depth in 1995 to 174 m in 2003 and this dreissenid reached densities averaging 8,000/m2 at all sites < 90 m. During the same time period, Diporeia populations almost completely disappeared from 0–90 m depth, continuing a declining trend from 1994–1997 reported in previous studies. The average density of Diporeia in the 30–90 m depth interval decreased from 1,380/m2 to 63/m2 between 1997 and 2003. Prior to 2003, areas deeper than 90 m represented a refuge for Diporeia, but even these deep populations decreased, with densities declining from 2,181/m2 in 1999 to 545/m2 in 2003. Two common hypotheses for the decline of Diporeia in the Great Lakes are food limitation and a toxin/pathogen associated with dreissenid pseudofeces. The Diporeia decline in deep waters preceded the expansion of D. bugensis to these depths, and suggests that shallow dreissenid populations remotely influence profundal habitats. This pattern of decline is consistent with mechanisms that act from some distance including nearshore dreissenid grazing and downslope transport of pseudofeces.  相似文献   
133.
Abstract:   This paper examines the characteristics of firms that account for deferred tax liabilities related to government investment grants under an extended adoption timing period. Not only the recognition but also the timing decision is associated with changes in future performance and changes in the debt structure. Recognisers outperform non‐recognisers in the future, while early recognition is related to post recognition performance but only for those firms that currently perform well. Changes in the balance sheet structure are also related to both decisions. Firms with recent increases in the debt level tend to postpone recognition, while currently well‐performing firms that increase their future debt level are less likely to recognise deferred taxes.  相似文献   
134.
Gordonia amarae is a right-angled branching filament belonging to the mycolic acid-containing Actinobacteria which is commonly found in many foaming activated sludge wastewater treatment plants. Although studies on different substrates as sole carbon sources by pure cultures of G. amarae have been carried out, none have examined substrate uptake by this organism in situ. Uptake of several hydrophilic and hydrophobic substrates by G. amarae was evaluated in situ using a combination of fluorescence in situ hybridization and microautoradiography. G. amarae could assimilate a range of both hydrophilic and hydrophobic substrates. From the data, G. amarae appears to be physiologically active under aerobic, anaerobic and anoxic condition (NO2 and NO3) for some substrates. This might explain why attempts to control foaming caused by G. amarae using anoxic and anaerobic selectors have been unsuccessful. This study emphasizes that bacteria can behave differently in situ to pure cultures and that it is important to evaluate the in situ physiology of these bacteria if we are to better understand their role in the wastewater treatment process.  相似文献   
135.
I analyze a well-known and moving passage from John Steinbeck's novelThe Grapes of Wrath. This passage provides an excellent illustration of one of the central questions about corporate moral agency: Is corporate moral agency anything over and above the agency of individual human beings? The passage in question is a debate about whether or not the actions of a particular company are anything over and above the actions of individual human beings.  相似文献   
136.
This paper examines the return of the original class of common stock around the announcement of the creation of a second class of stock. As in previous studies, this one finds a generally ambiguous market reaction on the first public announcement. However, this paper offers new evidence that both the voting rights and the compensation for loss of voting rights are important determinants of the market's reaction. Specifically, it demonstrates that a second class stock issue that contains no compensation for the lost voting rights results in negative returns. When the original stockholders are compensated for lost voting rights, they experience positive abnormal returns.  相似文献   
137.
This article describes a repeated game of multimarket contact, designed to be played throughout an entire term. Besides enjoying reciprocal advantages in their home markets, firms are perfectly informed after every round about each other's decisions. For most of the game, it appears there is always a future in which to punish deviations, and (with the game's parameters) zero-cost punishments can always be implemented. Thus the game provides all the elements for an escape from the prisoner's dilemma. Theoretical foundations, predictions, and some results are also discussed.  相似文献   
138.
139.
As developing countries search for ways to promote capital formation through the establishment of organized exchanges, they will need to pay more attention to the role of risk management in the securities settlement process. The delivery-versus-payment (DVP) agents that facilitate the process of exchanging securities for funds in most world markets have both the incentive and comparative informational advantage to monitor, measure, and manage risks inherent in the securities settlement system.
Unfortunately, most DVP agents have accomplished this task to date through the cumbersome use of position and net debit limits, capital requirements, and collateral requirements. Such limits and requirements are almost everywhere based on relatively arbitrary criteria that may have no relation to the actual replacement cost, principal, or liquidity risk of the transaction, portfolio, or participant on which they are imposed.
To remedy this shortcoming in the current state of risk management at DVP agents, this article holds out the possibility of integrated, comprehensive risk management processes that emphasize and rely on forward-looking measures of risk for individual brokers and across brokers. Many risk measures could serve the settlement agent's purposes, including "value at risk" (or "VaR"), "below target risk,""below-target probability," and "downside semi-variance." The actual summary risk measure used for risk monitoring and control is not as important as the methodology used to generate that risk measure. "The goal of such a process," as the authors put it, "is to ensure that the risks to which a settlement agent and its residual claimants are exposed are those risks to which the agent's shareholders think they are and want to be exposed."  相似文献   
140.
The Internet furore over Intel's flawed Pentium chip provides an important case study of the ethical ambiguity of internet communications and the legitimacy of certain forms of "electronic activism". Joseph Badaracco, Jr., is John Shad Professor of Business Ethics at the Harvard Business School and his co-author is a former Research Associate at Harvard and currently on the editorial staff of Inc . magazine.  相似文献   
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