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981.
This article prints two hitherto unknown letters by Adam Smith to Henry Beaufoy (1750-95), MP for Great Yarmouth, concerning legislation that beaufoy and William Pitt had promoted. In the first letter (14 November 1786) Smith comments on changes to existing customs and exicese regulations(26 Geo. III c.49 and c.59), and implicitly takes some credit for legislation concerning the hering fishery (25 Geo. III c.65, 26 Geo. III c.81, 27 Geo. III c.10). In the second letter (29 January 1787) Smith expresses considerable pessimism about the philanthropic proposals of the British Fisheries Society to build fishing villages in the Highlands and Islands of Scotland.  相似文献   
982.
This report examines environmental prospects for the twenty-first century, and then suggests some appropriate long-term management strategies and research priorities. A few current global trends (e.g., increasing concentrations of atmospheric trace gases, population, agricultural production) are practically irreversible over the next couple of decades due to inertias in the systems involved. However, there are bound to be nonlinearities, discontinuities, and surprises in the behavior of many environmental and socioeconomic systems. In fact, the main challenge for managers, policy analysts, and politicians is to develop strategies that are robust in response to these surprises, exploiting the opportunities as well as softening the shocks that may arise.The main characteristics of such strategies are that they be adaptive, interdisciplinary, and cross-sectoral. As pointed out by Harvey Brooks [2], we must avoid partial solutions that may be optimal for a particular sector or decade, but which are far from optimal for the biosphere as a whole over the long term.  相似文献   
983.
984.
Utilising historical and contemporary studies of metalworkingplants, a review of current trends in labour-management relations,and observations from 15 years as a machinist and local unionofficer, the author describes the efforts of US workers andtheir local unions to play a positive role in shop-floor productionmatters in the post-Second World War period, only to be rebuffedby corporations intent on gaining hegemony on the factory floor.This history is juxtaposed to contemporary efforts by managersto kindle interest among workers in participating in variousshop-floor continuous improvement schemes, in the context ofthe implicit and explicit threats to employment security thatglobal production flexibility provides to corporations.  相似文献   
985.
986.
Objective: The recent development of the EDWARDS INTUITY Elite? (EIE) valve system enables the rapid deployment of a prosthetic surgical heart valve in an aortic valve replacement (AVR) procedure via both the minimally invasive (MISAVR) and conventional (CAVR) approaches. In order to understand its economic value, this study performed a cost evaluation of the EIE valve system used in a MIS rapid-deployment approach (MIS-RDAVR) vs MISAVR and CAVR, respectively, compared to standard prosthetic aortic valves.

Methods: A simulation model was developed using TreeAge (and validated with MS Excel) to compare the inpatient utilization and complication costs for each treatment arm. Thirty-day clinical end-points for the MIS-RDAVR (mortality and complications) were taken from the TRANSFORM trial; and a best evidence review of the published literature was used for the MISAVR and CAVR approaches. Studies were pooled and parameter estimates were weighted by sample size in order to compare the TRANSFORM patients. Cost data (2016 USD) were taken from the Premier database. Incremental cost and cost-effectiveness was assessed and one-way/probabilistic sensitivity analyses performed to gauge the robustness of the results.

Results: MIS-RDAVR costs $2,621 less than CAVR and had lower mortality rates, making it a superior (dominant) technology relative to CAVR. MIS-RDAVR costs $4,560 more than MISAVR, but was associated with an additional 0.20 life years-per-patient. This implies a cost-effectiveness ratio of $22,903 per-life-year-gained. Thus, MIS-RDAVR is cost-effective compared to MISAVR.

Conclusions: The EIE valve system deployed in a MIS approach appears to be a cost-effective technology compared to MISAVR and CAVR. When compared to CAVR it may achieve cost savings as well. These results suggest that MIS-RDAVR confers superior economic value compared to both standard MISAVR and CAVR via lowered key complication rates (re-operation, renal complications, wound infection, TIA, endocarditis) and utilization (cross-clamp time, hospital ward days).  相似文献   
987.
Summary. In a Bayesian model of group decision-making, dependence among the agents' types has been shown to have a beneficial effect on the design of incentive compatible mechanisms that achieve the efficient choice associated with complete information. This effect is shown here to depend as much upon the use of large monetary transfers among the agents as it does upon dependence: if the transfers are bounded in magnitude, then nonexistence in the case of independence of an efficient, incentive compatible, ex ante budget-balanced and interim individually rational mechanism is robust to the introduction of a small amount of dependence among types. This robustness result supports the use of the simplifying assumption of independence in mechanism design. Received: October 28, 1996; revised version: May 28, 1997  相似文献   
988.
  总被引:1,自引:0,他引:1  
The article analyzes the welfare cost of the U.S. sugar program using a multimarket model of U.S. sweetener markets. The latter includes raw crops, sugar extraction and refining, and sweetener users (food-processing industries and final consumers). The authors address the industrial organization of food industries using sweeteners and treat the United States as a large importer. With the removal of the program, this article estimates (all figures in 1999 dollars) that in 1998 cane growers, sugar beet growers, and processors would have lost $307, $650, and $89 million, respectively; sweetener users would have gained $1.9 billion. World prices would have increased by 13.2%. The deadweight loss of the program is estimated at $532 million.  相似文献   
989.
990.
    
David Butt's multi-sectoral long-term theory of growth is summarized in mathematical terms and applied to the problem of allocating investment to many sectors, especially by modifying Nurkse's Balanced Growth doctrine to take account of changes in relative prices that occur during the growth process. The case of mechanization of the food sector is discussed in some detail.  相似文献   
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