Influence of Argentine and coastal brown ant (Hymenoptera: Formicidae) invasions on ant communities in Perth gardens,Western Australia

A survey examined the influence of Argentine (Linepithema humile (Mayr)) and coastal brown ant (Pheidole megacephala (Fabricius)) populations on other ants in the Perth metropolitan area, Western Australia. Twelve gardens (yards) were sampled; four infested by Argentine ants, three infested by coastal brown ants, and five controls where these two tramp ants were absent or collected only as isolated strays. Collection methods used were pitfall trapping and hand collection. A total of 27 species was recorded. Eight of these species, including the above two tramp ants, are non-native to the region. Pheidole megacephala was the most abundant species, comprising 95.4% of ants in P. megacephala–infested gardens. Linepithema humile comprised 92.1% of ants in L. humile–infested gardens. Other common ants were the native Iridomyrmex chasei and the introduced species Tetramorium simillimum and Tetramorium bicarinatum. The cryptic introduced species Cardiocondyla nuda and Tetramorium simillimum appear able to persist in small numbers in L. humile–infested gardens, but virtually no other ant species occurred where the coastal brown ant was well established. Mean richness, diversity, and evenness were significantly different between P. megacephala–infested and control gardens, and significantly different between L. humile–infested and control gardens. Diversity and evenness, but not richness, were significantly different between P. megacephala–infested and L. humile–infested gardens. Ordination analysis revealed that the three types of gardens had very different ant community profiles.     

Gambling Behaviors Among Oxford House Residents: A Preliminary Investigation

ABSTRACT

The present study investigated the prevalence of gambling behaviors among 71 individuals recovering from substance-dependent disorders and living in self-run recovery homes (Oxford Houses). Residents were given the South Oaks Gambling Screen to assess gambling behaviors and pathological gambling, and 19.7% of the sample was identified as having probable pathological gambling. These residents reported proportionately more involvement in a variety of gambling behaviors than other residents. Engagement in various gambling activities was consistent with previous investigations and suggested that self-run recovery homes such as Oxford Houses might be suitable referral sources for recovering persons who have comorbid gambling problems.     

Gambling Behaviors Among Oxford House Residents: A Preliminary Investigation

The present study investigated the prevalence of gambling behaviors among 71 individuals recovering from substance-dependent disorders and living in self-run recovery homes (Oxford Houses). Residents were given the South Oaks Gambling Screen to assess gambling behaviors and pathological gambling, and 19.7% of the sample was identified as having probable pathological gambling. These residents reported proportionately more involvement in a variety of gambling behaviors than other residents. Engagement in various gambling activities was consistent with previous investigations and suggested that self-run recovery homes such as Oxford Houses might be suitable referral sources for recovering persons who have comorbid gambling problems.     

Modeling and Forecasting Health Expectancy: Theoretical Framework and Application

Life expectancy continues to grow in most Western countries; however, a major remaining question is whether longer life expectancy will be associated with more or fewer life years spent with poor health. Therefore, complementing forecasts of life expectancy with forecasts of health expectancies is useful. To forecast health expectancy, an extension of the stochastic extrapolative models developed for forecasting total life expectancy could be applied, but instead of projecting total mortality and using regular life tables, one could project transition probabilities between health states simultaneously and use multistate life table methods. In this article, we present a theoretical framework for a multistate life table model in which the transition probabilities depend on age and calendar time. The goal of our study is to describe a model that projects transition probabilities by the Lee-Carter method, and to illustrate how it can be used to forecast future health expectancy with prediction intervals around the estimates. We applied the method to data on the Dutch population aged 55 and older, and projected transition probabilities until 2030 to obtain forecasts of life expectancy, disability-free life expectancy, and probability of compression of disability.