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61.
A dynamic equilibrium model is constructed in which agents with access to different information sets participate in the capital market. Agents must use the equilibrium price of capital to make optimal forecasts of the return to holding capital. Examples show that the volume of trade, as well as the price of capital, can be highly correlated with a measure of the information content of prices. This measure of information is the difference between the unconditional entropy of the dividend and the entropy of the dividend conditional on observing the price of capital.  相似文献   
62.
Extensification of agriculture is one of the major factors contributing to the destruction of forests in Africa. In Sudan, such horizontal expansion comes at the expense of land devoted to trees and other vegetation, thereby inducing conditions that are inimical to sustainable agricultural production. Different factors have contributed to extensification. Although high economic returns from crop (mainly sorghum) production was an important factor encouraging extensification of rainfed mechanized farming, other factors outside agriculture have also contributed to that expansion. This paper uses data from eastern Sudan and an acreage response model, to identify the most important factors influencing acreage expansion. Different measures and forms of risk were used in the acreage response model. The paper shows how policies in the energy sector can indirectly influence acreage expansion in the agricultural sector.  相似文献   
63.
Although many challenges remain, business ethics is flourishing in North America. Prominent organizations give annual business ethics awards, investments in socially screened mutual funds are increasing, ethics officers and corporate ombudspersons are more common and more influential, and new ideas are being tested in practice. On the academic side, two major journals specializing in business ethics are well-established and other major journals often include articles on business ethics and new organizations emphasizing ethics have been initiated. Within business schools, the number of endowed chairs is growing and the ethics curriculum is expanding. Canada is a major player in the business ethics discipline while business ethics in Mexico is just beginning to emerge as a focus of interest in both the business and academic communities.  相似文献   
64.
A study of the effect of age and gender upon student business ethics   总被引:1,自引:0,他引:1  
The present survey was voluntarily and anonymously completed by 2,196 students enrolled in business courses at the University of Southern Mississippi. The intent of the survey was to determine whether or not age or gender played a role in a person's perception of proper ethical conduct.The findings suggests that gender is a significant factor in the determination of ethical conduct and that females are more ethical than males in their perception of business ethical situations.Students were divided into groups according to age as follows: under 21 years, 22–30 years, 31–40 years, and 40 plus years. The results of this survey also suggest that age is a determining factor in making ethical decisions. The statistics suggest that those students falling in the 40 plus years age group were the most ethical, followed in order by the 31–40 group, the 22–30 group and those of 21 years of age and under.Durwood Ruegger is currently an Associate Professor of Finance and General Business at the University of Southern Mississippi. Prior to joining the University, he was a practicing attorney and former municipal judge. His publications have appeared in theJournal of Health and Human Resources Administration, Labor Law Journal, Business Insights, andThe Practical Real Estate Lawyer.Ernest W. King is an Assistant Professor of Finance and General Business at the University of Southern Mississippi. He is a member of the Florida and Washington, D.C. Bars. His publications have appeared inBusiness Insights, Nursing Administration Quarterly, and theCPCU Journal.  相似文献   
65.
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics.  相似文献   
66.
This article presents an application of Prezeworski and Teune's so-called “identity-equivalence method” to a large set of indicators of political participation. By relaxing commonly held assumptions about necessary distinctions among types of participation, it is found that the distinction between “conventional” and “unconventional” modes of participation is unnecessary, while the distinction between “government” and “nongovernment” has some merit. The findings also lend further support to the claims of Prezeworski and Teune that the identity-equivalence method is preferable to the identical indicator method.  相似文献   
67.
68.
Editorial     
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69.
In this study, four similar bench-scale submerged Anoxic/Oxic Membrane Bioreactors (MBR) were used simultaneously to investigate the effects of solids retention time (SRT) on organic and nitrogen removal in MBR for treating domestic wastewater. COD removal efficiencies in all reactors were consistently above 94% under steady state conditions. Complete conversion of NH(4+)-N to NO(3-)-N was readily achieved over a feed NH(4+)-N concentration range of 30 to 50 mg/L. It was also observed that SRT did not significantly affect the nitrification in the MBR systems investigated. The average denitrification efficiencies for the 3, 5, 10 and 20 days SRT operations were 43.9, 32.6, 47.5 and 66.5%, respectively. In general, the average effluent nitrogen concentrations, which were mainly nitrate, were about 22.2, 27.6, 21.7 and 13.9 mg/L for the 3, 5, 10 and 20 days SRT systems, respectively. The rate of membrane fouling at 3 days SRT operation was more rapid than that observed at 5 days SRT. No fouling was noted in the 10 days and 20 days SRT systems during the entire period of study.  相似文献   
70.
At present, our society and its social security system are not prepared to cope with the challenges resulting from the continuous increase of life expectancy. The traditional concept of disease has to be modified for serving the special needs of the elderly. The optimistic compression of disease theory is an intriguing model, but lacks prove by available data. The anti-aging boom diverts the focus from the social and financial burden that will be unevitably caused by long-term care in the future. If there will not be an — up to now unforeseeable — breakthrough in research, particularly dementia will have an enormous impact on social cost which is often underestimated.  相似文献   
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