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31.
S B Watson M Charlton Y R Rao T Howell J Ridal B Brownlee C Marvin S Millard 《Water science and technology》2007,55(5):1-8
The Laurentian Great Lakes of North America are a drinking water source for millions of Canadian and US consumers. These waterbodies have undergone extensive change over the past century as a result of widespread degradation and remediation. Many of the Lakes are prone to taste and odour (T&O), and although these outbreaks have been poorly monitored, evidence suggests that they are increasing in frequency. Tracing and controlling T&O in such large systems presents a challenging task, due to their physical size and complexity. This paper presents an overview of recent investigative and management approaches to T&O in Lake Ontario and its outflow, the St. Lawrence River. We have identified three distinct patterns of T&O in these source-waters, caused by geosmin and 2-methylisoborneol and differing in their planktonic and benthic sources, and temporal and spatial dynamics. Each pattern has required a different approach by scientists and management, in partnership with the water industry. We have shown these T&O outbreaks are caused and moderated by physical, chemical and biological mechanisms over a spectrum of spatial and temporal scales. Canadian municipalities affected by these outbreaks have been key to the investigation of the links between T&O and ecosystem processes with the aim to develop more proactive water treatment and long-term management. 相似文献
32.
In this study, the effects of the phosphonic acid based sequestering agent EDTMPA used in the textile dye baths on colour and organic matter removal by ozone oxidation was experimentally investigated. Procion Navy HEXL dyestuff that has been commonly used for the reactive dyeing of cellulose fibers was selected as the model component. The organic matter oxidation by ozone was determined to obey the pseudo-first order kinetics as they are treated singly or in combination. COD removal rates obtained from pseudo-first order reaction kinetics showed that oxidation of Navy HEXL alone (0.0947 L/min) was faster than that of EDTMPA (0.0171 L/min) and EDTMPA with dye (0.0155 L/min) at pH 3.0. It was also found that reaction rates of single EDTMPA removal and EDTMPA and dye mixture removal increased as the reaction pH was increased from 3.0 to 10.5. 相似文献
33.
Darren T. Roulstone 《Journal of Accounting Research》2003,41(3):525-551
In this study I investigate the relation between firm‐level insider‐trading restrictions and executive compensation. Using a trading‐window proxy for the existence of such restrictions, I test predictions that insiders will demand compensation for these restrictions and that firms will need to increase incentives to restricted insiders. I find that firms that restrict insider trading pay a premium in total compensation relative to firms not restricting insider trading, after controlling for economic determinants of pay. Furthermore, these firms use more incentive‐based compensation and their insiders hold larger equity incentives relative to firms that do not restrict insider trading. These results hold after controlling for the endogenous decision to restrict insiders and are consistent with the notion that insider trading plays a role in rewarding and motivating executives. 相似文献
34.
A statistically optimal inference about agents' ex ante price expectations within the US broiler market is derived using futures prices of related commodities along with a quasi‐rational forecasting regression equation. The modelling approach, which builds on a Hamilton‐type framework, includes endogenous production and allows expected cash price to be decomposed into anticipated and unanticipated components. We therefore infer the relative importance of various informational sources in expectation formation. Results show that, in addition to the quasi‐rational forecast, the true supply shock, future prices, and ex post commodity price forecast errors have, at times, been influential in broiler producers' price expectations. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
35.
The pensions pillarisation agenda envisages a reduction in the role of social insurance while simultaneously advocating the parallel expansion of fully funded private sector, occupational and personal retirement contingencies. Widespread perception of looming state failure in the field of pensions delivery highlights the inherent limitations of current pension delivery arrangements. However, moves to de-emphasise the provision afforded by, predominantly, monopillar state-mandated pension systems by expanding private privision represent short-term palliative responses to deep rooted structural and demographic problems. Multipillar systems appear no more capable of guaranteeing system funding in the face of demographic ageing and structural unemployment than existing monopillar systems. Moreover, a diminished role for social insurance will leave the low paid and unemployed significantly more vulnerable in old age. Consequently, this paper argues for a pension reform agenda which, in terms of levels of income substitution, will secure an adequate social insurance element into the future. 相似文献
36.
Previous research on unit management buyouts, UMBs, has shown that selling firms benefit from the selloff transaction. The current research demonstrates that when the selling firm has either poor liquidity or poor earnings, selling firm shareholders do not benefit as much. We hypothesize that the unit managers have knowledge about the selling firm's difficulties so they do not pay as large a premium for the assets. Since the unit managers technically are employed by the selling firm shareholders, their bargaining to achieve a better price is an agency cost. Finally, selloff frequency does not affect seller abnormal returns. 相似文献
37.
Bradley T. Ewing 《The Review of Black Political Economy》1995,24(1):65-78
This article examines the effects of high school athletic participation on the future wages of black males. Our evidence suggests that former black male athletes receive significantly greater wages than their otherwise comparable counterparts. Data from the National Longitudinal Survey of Youth was used for the analysis and allows for comparisons of the athlete premium to be made at different points in time. Both the human capital and signaling models are discussed. There appears to be a once and for all enhancement to human capital that accrues to black males who participated in high school athletics. The article adds to the literature on determinants of black male wages and on the earnings effects of athletic participation. 相似文献
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40.
D.T. Merrett 《Australian economic history review》1997,37(3):181-201
This survey article examines the interaction between the domestic capital markets and capital formation in Australia from the 1890s up to the end of World War II. The disenchantment of the City of London with Australian securities in the 1890s opened a window for the development of domestic capital markets. It was the demands of the government for funds, especially during both wars, that transformed the scale and character of local markets. Local deposit taking institutions and stock exchanges handled a sufficient volume of domestic savings to fund the lion's share of both public and private sector capital formation. 相似文献