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This paper examines the common stock returns of three groups of bidders that purchased brokerage houses. Only in the cases of horizontal mergers, one brokerage house purchasing another, are there abnormal returns associated with the purchase. Neither bank holding company bidders nor non-financial bidders gain significantly when purchasing a brokerage house. Bank holding company bidders face considerable regulatory delays, and these economic disturbances may eliminate their gains. Bank holding company expansion into these non-bank activities does not appear, at the time of announcement, to either hurt or benefit them; hence, this expansion does not appear to further the loss exposure of the Federal Deposit Insurance Corporation.  相似文献   
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This paper investigates whether governments can change market structures through interventions. We study the effects of four political events over the life cycle of the market for daily newspapers in the Netherlands. We find that policy measures meant to lower entry barriers in an expanding industry created new entry and increased survival chances for potential entrants and incumbent newspapers. Exit barrier enhancing policies to reduce concentration tendencies have not been successful.  相似文献   
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Post-treatment of an UASB reactor effluent, fed with domestic sewage, was conducted using two-stage flotation and UV disinfection. Results were compared to those obtained in a parallel stabilisation pond. The first flotation stage employed 5 - 7.5 mg L(-1) cationic flocculant to separate off more than 99% of the suspended solids. Then, phosphate ions were completely recovered using carrier flotation with 5-25 mg L(-1) of Fe (FeCl3) at pH 6.3-7.0. This staged flotation led to high recoveries of water and allowed us to separate organic matter and phosphate bearing sludge. The water still contained about 1 x 10(2) NMP/100 mL total coliforms, which were removed using UV radiation to below detection levels. Final water turbidity was < 1.0 NTU, COD < 20 mg L(-1) O2 and 71 mNm(-1), the liquid/air interfacial tension. This flotation-UV flowsheet was found to be more efficient than the treatment in the stabilisation pond and appears to have some potential for water reuse. Results were discussed in terms of the biological, chemical and physicochemical mechanisms involved.  相似文献   
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Hospitals must drastically redesign themselves and revise their operations to be successful. Four major redesign initiatives will enable the traditional hospital to provide effective patient care while attaining its own profitability goals.  相似文献   
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The paper hypothesizes that diversification by firms based in the pharmaceutical industry during the 1977-86 time period was primarily undertaken to reduce the risks associated with being dependent upon a technologically dynamic environment. Consistent with this non-efficiency motive for diversification, declining economic performance is predicted. A longitudinal empirical analysis provides support for these propositions.  相似文献   
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