Effects of urbanization on macroinvertebrates in tributaries of the St. Johns River, Florida, USA

The effects of urbanization on hydrology, water quality and macroinvertebrates were examined in 7 headwater tributaries of the St. Johns River in the Atlantic Coastal Plain of northeast Florida. All streams had sandy substrata and drained small catchments (24?C231?ha) that ranged from 0 to 51% total impervious area (TIA). Streams unaffected by urbanization had intermittent stream flow and completely dry channels for several weeks in autumn and spring. Urbanized streams always possessed channel water, but 2 streams ceased flowing and became stagnant in autumn and spring. Principle components analysis of chemical and physical measures (i.e. conductivity, nutrients, pH, metals, and stream flow) produced one axis (PCA1) that explained 54% of the total variation among the streams. The variables that loaded negatively on this axis were associated with low flows, while the variables that loaded positively were associated with urban land-use. PCA1 was also positively associated with %TIA. Macroinvertebrate richness ranged from 27 to 45 taxa and was positively associated with %TIA. Macroinvertebrate biomass ranged from 3 to 45?g AFDM/m² and showed a significant, exponential relationship with PCA1 (r ²?=?0.93) with greatest biomass occurring at intermediate %TIA. Invertebrate community structure in the urbanized streams appeared to be mainly influenced by hydrologic factors (perennial vs. intermittent flow regimes). The effects of urbanization on both hydrological and biological variables among the study streams were apparent, but also influenced by site-specific conditions.     

Hitting the jackpot: the influence of monetary payout on gambling behaviour

Restrictions on monetary payout may promote player engagement in gambling as a form of entertainment rather than as a source of income. Our objective was to evaluate the effects of monetary prize magnitude upon gambling behaviour in a community sample, and the degree to which this association is moderated by gambling risk factors. One hundred and eighty-seven adults completed an online survey assessing motivation, impulsivity and affect. Participants were given a series of vignettes and asked to estimate how much they would gamble to win monetary prizes of increasing amounts with and without accrued gambling debt. Participants reported increased gambling in response to increased monetary payout. Debt moderated these outcomes, such that electronic gaming machine (EGM) and lottery expenditures and number of lottery games played decreased with increased debt; this effect was most pronounced at elevated monetary prizes. The association between duration of EGM play and monetary payout was moderated by gender only. Results suggest that self-reported gambling behaviours increased with monetary payout even across qualitatively different gambling products, and across gamblers with different motivations for gambling, levels of impulsivity, and negative affect. The restriction of monetary payouts warrants further research attention as a form of problem gambling prevention.     

The age-varying effects of adolescent stress on impulsivity and sensation seeking

Adolescence is defined in part by heightened exposure and sensitivity to stressors. In a longitudinal cohort of youth at risk for substance use problems, we examined the age-varying relationship between stress exposure and traits that are central to the dual systems model. The positive associations between stress exposure, impulsivity, sensation seeking varied as function of age. Specifically, the influence of stress exposure on impulsivity strengthened during early adolescence and remained stable into early adulthood, while the influence of stress exposure on sensation seeking strengthened from early- to mid-adolescence and weakened thereafter. These findings suggest that the maturational imbalance between the capacity to regulate impulsive tendencies and sensation seeking may be exaggerated for youth who are exposed to a high number of stressors.     

Rate-optimal nonparametric estimation in classical and Berkson errors-in-variables problems

We consider nonparametric estimation of a regression curve when the data are observed with Berkson errors or with a mixture of classical and Berkson errors. In this context, other existing nonparametric procedures can either estimate the regression curve consistently on a very small interval or require complicated inversion of an estimator of the Fourier transform of a nonparametric regression estimator. We introduce a new estimation procedure which is simpler to implement, and study its asymptotic properties. We derive convergence rates which are faster than those previously obtained in the literature, and we prove that these rates are optimal. We suggest a data-driven bandwidth selector and apply our method to some simulated examples.     

Intergenerational Housing: The Case of Humanitas Netherlands

We analyze a case study of an innovative intergenerational housing arrangement in the Netherlands as an example of how a local long-term elderly care practice evolved in response to contemporary challenges. Identified elements of the established local practice relate to the characteristics and strategies of an institutional entrepreneur and elements of the new practice that comes into being, in which reciprocity and mutual learning have a central place. These elements might benefit future elderly housing initiatives as well.     

The Impacts of Education,Adverse Childhood Experience,and Nativity on Intimate Partner Violence

This paper tested an implication of household bargaining theory, that women with higher human capital experience less intimate partner violence. Relying on a single source of income imposes a barrier to leaving an abusive relationship. Women with higher human capital are better equipped to leave a relationship, which allows them to tolerate less violence in a relationship. Using a California health survey dataset, we found that more educated women were less likely to experience spousal violence. We used the detailed nature of the data to control for commonly omitted variables such as adverse childhood experiences. In addition, we found that the effect of education on intimate partner violence varied by nativity (US-born vs. foreign-born) and was smaller for foreign-born women. Drawing from the literature on the returns to education by race, we hypothesized that foreign-born women have a lower return on human capital, which in turn moderated the effect of education on household bargaining power.     

Masculine domination and gender subtexts: The role of female professionals in the renewal of the Swedish video game industry

The video game industry is a showcase industry in the entrepreneurial, knowledge-intensive, and technology-based economy. Despite recent technological shifts rendering digital media portable in the form of smartphones, tablets, and laptops, attracting new categories of gamers, most notably women above the age of 35, the video game industry is struggling to handle its masculine domination, prescribing specific and gendered divisions of labor in terms of lowering thresholds for female video game developers. This article reports on empirical material based on interviews from the burgeoning Swedish video game industry and suggests that female professionals entering the industry encounter inherited gendered beliefs and ways of organizing work which locate women in specific, and not always desirable, roles within the industry. In this regime of masculine domination, the study concludes, female video game developers are understood as a particular group primarily knowledgeable about female gamers’ preferences and not as the possessors of general skills attractive to the video game companies. Ultimately, the masculine domination and the historical gendered divisions of labor are preventing the industry from creating more gender-equal workplaces and, as a consequence, fully exploiting market potentials.