Combining pheromone-baited and food-baited traps for insect pest control: Effects of additional control by parasitoids

Summary Two age-structured population dynamic models are analyzed in which pheromone-baited trapping and food-baited trapping are used simultaneously to eradicate an insect pest. The pest species is assumed to be under partial control by a host-specific parasitoid species. The two models assume that density-dependent population regulation is accomplished either by host larval competition or by means of oviposition interference among the parasitoids. The two trap types interact in a positive synergistic manner and this combination appears to be very promising as a useful combination of pest control methods. Several features of the system are examined; the feature which appears to cause the greatest problem is the possibility of the parasitoids being attracted to the pheromone or the food traps. In either case, the degree of attraction does not have to be very great to undermine the control effort. It is seen that food trapping becomes indispensible if host pheromone is used by the parasitoids as a host-locating kairomone. If odor in the food traps is used by the parasitoids as kairomone, then the situation appears more optimistic, as the reduction in efficiency of the food traps appears much less than with the pheromone traps when pheromone acts as kairomone.     

A reassessment of the demography of traditional rural China

An analysis of the composition, characteristics, and vital processes of the population of rural mainland China was undertaken using data collected as part of a study of land utilization carried out by Naking University in 1929-1931. These data have been reappraised using techniques for demographic analysis of faulty data which shows a consistent picture of the Chinese farmer of high morta moderate fertility, and early and universal marriage. Estimates of the singulate mean age at marriage was 17.5 for females and 21.3 for males. Fewer than 1 in 1000 women and 3 in 1000 men never married. The reported parity of older women was only slightly above 5, which disputes the very large historical family size that has been imputed to the chinese. There was a life expectancy of less than 25 years for each sex, and very high infant mortality. These characteristics were of sufficient persistence to have generated a stable age distribution.     

The intelligence of Twins. A comparative study of eleven-year-old twins. II

The scores of about one thousand Scottish eleven-year-old twins on a group intelligence test are compared with those of a similar group of about seven thousand non-twin children. The average score of the twins is found to be significantly lower than that of the non-twins. This difference is examined in connexion with the age of the child's mother, the degree of overcrowding in the home, and the occupation of the father. The mothers of the twins are found to be significantly older than those of the non-twins. The relationship of twinning and fertility is examined. There is also a slight predominance of twins in the higher social classes. Despite differences in family structure and social environment, the twins remain of lower average. intelligence throughout.     

A feminist history of Australian midwifery from colonisation until the 1980s

This paper uses a feminist interpretation and secondary sources to describe the history of Australian midwifery from colonisation until the 1980s. There have been too few midwife scholars who have had access to or used primary data collections to describe the role and place of midwives in the colonising community. I draw on a range of biography, medical literature and work by sociologists and economic historians to produce a limited picture of the history of professional midwifery. This helps to explain the position of midwives today and the problematic relationship we often have with medicine.     

Risk factors for preterm,low birthweight and small for gestational age births among Aboriginal women from remote communities in Northern Australia

Objective

To identify the risk factors for preterm birth, low birthweight and small for gestational age babies among remote-dwelling Aboriginal women.

Pheromone trapping models for pest control: Effects of mating patterns and immigration

Summary Several models are presented which examine pest population behaviour with the release of female sex pheromones for the attraction and annihilation of males. These models include male polygamy and female monogamy, various mating frequencies, delayed mating of females, immigration of one or all individual types, and differential survivorship of males and females. In all the models there are two steady states, a stable s.s. at the origin and an unstable s.s. in the positive domain for a given value of pheromone release rate. In all the models, control relies on the reduced ability of males to fertilize virgin females following trapping and male annihilation. As such, control is very sensitive to mating frequency, being very difficult when males mate frequently. Control is also very difficult with the immigration of even a moderate number of fertilized females. Control is much easier when mating is delayed, especially if survivorship is low, or with density dependent population regulation.     

Motivational postures and compliance with environmental law in Australian agriculture

Motivational posture theory is applied and extended to the context of Australian agriculture and environmental regulation. Regulatory failure in this area has been observed but little was known of the compliance attitudes and behaviours of farmers prior to this study. Agriculture covers over 60% of Australia’s land surface so this information is vital if environmental sustainability is to be achieved. A mail survey of 5235 farmers across Australia was conducted to examine motivational postures and attitudes to government, environmental problems, environmental laws and regulations and farm management behaviours. Four postures are empirically derived: one associated with compliance, here labelled “Aligned”, and three associated with non- or creative compliance: one Disengaged, one Game playing and one Resistant. Analysis of the characteristics of each group demonstrates that motivational postures are related to place, jurisdiction and degree of regulatory alignment: the degree of agreement between regulatees and regulators on the latter’s role and on the content, process and aims of regulatory interventions. Game players eschew a role for government. The Aligned support both government and regulations. Postures were predictive of beyond compliance behaviour. The Aligned were more likely to undertake beyond compliance behaviours and Game players least likely. Fiscal limitations were identified as restricting beyond compliance behaviours by many farmers. Environmental regulations are often contentious and therefore these findings may be helpful to authorities to more effectively engender compliance so that on-ground outcomes may be secured.