Time series of growth in use of oral contraception and the differential diffusion of oral anovulents

Abstract Differential growth in the use of oral anovulents is explored through construction of separate time series for Canadian women classified by religion, education, and nativity. The series suggest that native-born Roman Catholic women are as likely as native-born Protestant women to be using oral contraceptives by the terminal point of our series in 1967. The period of very rapid growth in the use of orals appears to have come to an end. Differential patterns of diffusion of oral contraception shown by the categories of women discussed, suggest sources of bias in the profile of an aggregate time series.     

Reflections on the demographic conditions needed to establish a U.S. stationary population growth

Abstract It is assumed that in the long run U.S. population growth will have to cease, as otherwise life will become physically impossible. Various hypothetical possibilities of achieving such a type of development are investigated. Alternatives of reproduction rate trends are considered in terms of alternatives of interactions of assumed age-specific fertility and mortality trends and these are computed and evaluated. The various computations then indicate the nature of childbearing attitudes and behaviour, which the 'average population' would have to adopt in order to achieve the desired stationary population growth after a certain period of time. On the other hand the results presented in the paper also indicate that a certain population growth (of the order of 30-50%) and change in age structure is inevitable in the coming 5-10 decades given the initial childbearing behaviour.     

SMPD Scenarios of Spatial Distribution of Human Population in China

Three scenarios of spatial distribution of human population in China are developed in the years 2010 and 2020, respectively by means of the method of surface modeling of population distribution (SMPD). Each one of the SMPD scenarios is defined as a plausible alternative future under particular assumptions of elevation, water system, net primary productivity (NPP), urbanization, transport infrastructure development, and population growth. The SMPD scenarios show that if population could freely migrate within the whole China, the balanced ratios of population in the western region, the middle region and the eastern region to total population in the whole China would be 16%, 33% and 52%, respectively.     

Immigrant quality and assimilation: a review of the U.S. literature

Empirical research on US immigrants is reviewed: their productivity and assimilation; their contribution and use of public services; and their impact on native Americans. I discuss the characteristics of cohorts of immigrants that enter the United States at different times, and then quantify the assimilation of immigrants, typically in terms of economic productivity of immigrants compared with natives. Few have found quantifiable negative effects of immigrants on native wages or unemployment in local labor markets, but a more general equilibrium approach than has been empirically implemented may be needed to draw any conclusions regarding the distributional consequences of immigration. Received: 22 September 1995 / Accepted: 2 March 1997     

A double epidemic: crystal methamphetamine drug use in relation to HIV transmission among gay men

Emerging research on methamphetamine use among gay men suggests that growth in the use of this drug could present serious problems for HIV/AIDS prevention within the gay community. This article summarizes current studies on the extent, role, and context of methamphetamine use among gay men and its relationship to high risk sexual behaviors related to HIV transmission. Methamphetamine is often used by gay men to initiate, enhance, and prolong sexual encounters. Use of the drug is, therefore, associated with particular environments where sexual contact among gay men is promoted, such as sex clubs and large "circuit" parties. Research with gay and bisexual men indicates that methamphetamine use is strongly associated with risky sexual behaviors that may transmit HIV. This relationship, coupled with emerging evidence that methamphetamine use is on the rise among gay men, suggests that the drug could exacerbate the HIV/AIDS epidemic among this community. The article offers recommendations for further research and suggestions for prevention programs regarding methamphetamine use by gay men.     

Smallpox in nineteenth-century India

This study uses the large, but neglected, body of Indian historical demographic and health data to show that smallpox was a major killer in past times. At the start of the nineteenth century roughly 80 percent of India's population had no effective protection against the disease, and in these circumstances virtually everyone suffered from it in childhood. The main exception was Bengal, where the indigenous practice of inoculation greatly limited the prevalence of the disease. Smallpox case fatality in India was high—around 25–30 percent in unprotected populations—and significantly higher than estimated for unprotected populations in eighteenth-century Europe. Although vaccination reached India in 1802, the practice spread slowly during the first half of the nineteenth century. From the 1870s onward there were considerable improvements in vaccination coverage. The study demonstrates a close link between the spread of vaccination and the decline of smallpox. Whereas at the start of the nineteenth century the disease may have accounted for more than 10 percent of all deaths in India, by the end of the century smallpox had become a comparatively minor cause of death as a result of improved vaccination coverage.     

Fiscal impacts of immigration to the United States

"The purpose of this paper is to fill a gap in the demographic literature by reviewing previous fiscal studies of immigration in the United States. Each study is introduced by describing the data it uses, the methodologies employed in calculating costs and revenues, and the resulting estimates of fiscal consequences. Evaluative comments are also stressed. Seventeen studies are included in this review, divided into those that emphasize national fiscal impacts (these studies aggregate the effects of immigrants across all levels of government), state fiscal impacts, and fiscal effects on local governments."     

Ephebophilia and the creation of a spiritual myth in the works of Ralph Nicholas Chubb

The writings of Chubb, a boy-lover inclined to spiritualism will be studied with a view to understanding how he created an exonerative myth to reconcile his sexual interest with his desire for spiritual fulfillment. In this myth Chubb is the prophet of a deity who looks like a young boy and loving boys has spiritual significance. Chubb's pre-modern perception of his sexual orientation helps us to understand the changing views of homosexuality. This study may help in understanding the relationship between sexual desire and the development of personal myths.     

Dynamics ofSitotroga cerealella (olivier) (lepidoptera: gelechiidae) andSitophilus zeamais motschulsky (Coleoptera: Curculionidae) populations in a small bulk of stored corn

Summary The dynamics of Angoumois grain moth,Sitotroga cerealella (Olivier), and maize weevil,Sitophilus zeamais Motschulsky, populations breeding in a small bulk (initially 5.36 t) of shelled corn were studied over an 8-year period by monthly sampling. The weevil population showed wide fluctuations in density superimposed on a general decline with time. The moth population showed no upward or downward trend for the first 60 months, although it fluctuated widely. Following a decline that occurred between 56 and 60 months, the moth population fluctuated within a much narrower range, and there was a general decrease in density with time. The decline of the weevil population paralleled deterioration of the corn as did that of the moth population after ca 60 months, and the decline of both species probably resulted from increasing scarcity of suitable breeding sites. Both populations exhibited seasonal variation in density with minima in late summer and early fall, following periods of adversely high temperatures in the storage shed. The populations increased during the fall, leveled off or declined slightly during the winter months, and then increased to maximum levels in late spring or early summer. It thus appears that high temperatures had a greater adverse effect on the populations than low temperatures. The grain moth and the maize weevil both tended to be randomly dispersed at low population levels and moderately aggregated at intermediate and high levels, although the degree of aggregation was not correlated with population density when low population levels were considered separately, and the maize weevil showed a greater tendency for aggregation than did the grain moth. Analysis of individual samples at fixed points in time showed a conspicuous bias for negative correlation between numbers of the two species within sampling quadrats, suggesting a tendency for the two species to segregate within the grain mass. This process could have resulted from behavioral differences or from the destruction of one species by the other. Competitive displacement of the grain moth by the maize weevil has been demonstrated in laboratory experiments but has rarely been observed under natural conditions, and in our study the two species coexisted for 8 years in a relatively small grain bulk.