The establishment of the presence and group classification of sperm in mixed stains by isoelectric focusing

The article deals with experimental data on design of the method used for detection of sperm, blood and vaginal secretions according to isoelectric points of acid phosphatases, differential diagnosis of ABO group antigens in "mixed" stains as well as detection of phenotype of red cell acid phosphatase by isoelectric focusing method.     

The population in a sociopolitical system in crisis: Mexico before the Revolution

The author reviews some of the literature on the Mexican Revolution in order to assess the impact of demographic change on the outcome of that conflict. Consideration is given to urbanization, spatial distribution, literacy, industrial growth and the employment opportunities it provided, and land conflicts caused by population growth. (SUMMARY IN ENG)     

The link between demographic events: a study of nuptiality patterns

The author examines links between the timing of various major life events (including women's age at marriage and the spacing of children) and the economic and urban development of a society, using Mexico as an example. The focus is on marriage patterns. She finds that nuptiality influences rural-urban migration for women, as do age and socioeconomic factors and husband's employment status. Data are from the Mexican Fertility Survey for the period 1976-1977. (SUMMARY IN ENG)     

Tollison costs and technological innovation: The case of environmental regulation

This paper departs from the Tullock cost paradigm that views competition for monopoly privilege as a welfare-inimical process that wastefully dissipates preexisting producers' surplus and, occasionally, leads to inefficient increases in costs and counterproductive uses of scarce resources. The potential availability of rent-seeking may bring about the elimination of inefficient regulatory regimes that retard or prevent the introduction of cost-reducing innovations. Air quality management is but one area in which innovation rent-seeking holds promise for concrete welfare gains. Researchers may wish to focus on institutional mechanisms designed to overcome the transactions costs and free rider disincentives to the formation of a coalition to seek innovation rents. An example of such a mechanism might be a joint venture that requires all venture members to engage in lobbying and to contribute to collective research efforts. These unaddressed questions await future research.The authors are grateful for the insightful comments of Gordon Tullock, Robert D. Tollison, Michael T. Marlow and J.R. Clark. The usual caveats apply. The views expressed herein are solely those of the authors and should not be taken to represent the views of their employers.