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.     

Editorial: Rich country,poor people

Editorial: Rich country, poor people     

Population undercount and social science research

The undercount problem in the decennial census has important implication for social science research based directly or indirectly on census data. Because undercount rates (or coverage rates) vary by age, race, residence, and other factors typically studied in social research, important conceptual difficulties arise in using census results to corroborate sampling frames or to validate survey results. Differential undercount, particularly for analyses based on small areas, could produce substantial variability in prevalence rates in cases where the denominators for those rates are derived from the census. Several examples where the undercount problem arises in social science research, including survey research, are considered. The adjustment problem—whether to adjust, how to adjust, and how much to adjust—is also considered from the point of view of social sicence research.     

The Contemporary Marriage and Fertility Revolutions in the West the Explanations Provided by Australian Participants

The last half century has witnessed both in Australia, and elsewhere in the West, first a “baby boom” (and marriage boom) and then a “baby bust” (and marriage bust). Economists, demographers, sociologists and social historians, especially in America, have developed theories to explain these phenomena. Presented to the Annual Meeting of the Population Association of America, New Orleans, 21–23 April 1988.     

Advancing Research on LGBTQ Microaggressions: A Psychometric Scoping Review of Measures

ABSTRACT

Understanding the nature and consequences of LGBTQ microaggressions is critical to fostering equity and wellbeing among sexual and gender minorities. Yet little guidance is available for researchers seeking psychometrically robust measures of subtle LGBTQ slights, invalidations, and insults. To address this gap, we conducted a scoping review of multi-item quantitative measures that included at least one question addressing LGBTQ microaggressions. This article reports the study characteristics and psychometric properties of 27 original measures we identified and their subsequent adaptations. The article concludes with an assessment of strengths and limitations of LGBTQ microaggression measurement, highlighting aspects of measurement innovation on which future researchers can build. As microaggressions remain a powerful and underexplored mechanism of sexual and gender minority oppression, this review will help to both advance methodological quality in this critical research area and enhance our understanding of how microaggressions manifest in the lives of LGBTQ individuals.     

Expression and ambivalence over expression of negative emotion:psychometric analysis in the Women's Health Initiative

Inhibition of emotional expression has been associated with the incidence and progression of breast cancer and other chronic illnesses. Others have theorized that it may not be repression itself, but rather ambivalence over the expression of emotions that is the important health-related factor. The Women's Health Initiative (WHI), a long-term, national study focusing on disease prevention among postmenopausal women, is unique in its assessment of expression and ambivalence of negative emotion in a large study sample of multiethnic, older women. Psychological factors such as expression of negative emotion and ambivalence about expression of emotion are also determined by social patterning. The current study examined the psychometric properties of the instruments used to measure each construct and variation across race/ethnicity and age. The analysis suggests that the scales can be used with confidence in diverse ethnic and age groups. Examining ambivalence about expression of negative emotion in future longitudinal research will further elucidate its role in predicting disease incidence and recovery, both important in reducing the public health burden of chronic disease.     

Migration, fertility, and state policy in Hubei Province, China

Despite China s one-child family planning policy, the nation experienced a slight rise in the birth rate in the mid-1980s. Many observers attributed this rise to the heightened fertility of those rural-to-urban migrants who moved without a change in registration (temporary migrants), presumably to avoid the surveillance of family planning programs at origin and destination. Using a sequential logit analysis with life-history data from a 1988 survey of Hubei Province, we test this possibility by comparing nonmigrants, permanent migrants, and temporary migrants. While changing family planning policies have a strong impact on timing of first birth and on the likelihood of higher-order births, migrants generally do not have more children than nonmigrants. In fact, migration tends to lower the propensity to have a child. More specifically, the fertility of temporary migrants does not differ significantly from that of other women.     

Methods, approaches and data sources for estimating stocks of irregular migrants

This paper presents a comprehensive review of available methods for sizing irregular migrant populations as a particular group in the study of hidden populations. Based on the existing body of literature on the subject, a generic classification scheme is developed that divides existing estimation procedures into subcategories like “approaches”, “methods” and “estimation techniques”. For each of these categories, basic principles, methodical strengths and weaknesses, as well as practical problems, are identified and discussed with the use of existing examples. Special emphasis is placed on data requirements, data shortcomings and possible estimation biases. In addition, based on the empirical classification and quality assessment of country-specific estimates developed in the CLANDESTINO research project, the potential and requirements for replicating best practice models in other countries are explored. Finally, a number of conclusions on the appropriate design of estimation projects are offered.