“Send Me Your Location”: Examining Cyber Dating Abuse Victimization and Self-Esteem in Adolescents

Although research on the impact cyber dating abuse (CDA) has on individuals’ psychological well-being is beginning to grow, little is known about its relation to self-esteem. This study examined the bidirectional relationship of CDA victimization and self-esteem in adolescents using a longitudinal design. Participants were 28 adolescents (71% female, 25% male, 4% transgender) ranging in age from 14 to 18 years (M = 15.89, SD = 1.29) who had been in a romantic relationship for at least one month. Participants completed self-report assessments of CDA victimization and self-esteem 3 months apart. It was hypothesized that a reciprocal relationship would emerge between self-esteem and CDA victimization, in which individuals with lower self-esteem at Time 1 would experience increased CDA from Time 1 to Time 2, and individuals who experienced more cyber dating abuse at Time 1 would show decreases in self-esteem from Time 1 to Time 2. Electronic intrusiveness and direct aggression, two subscales of CDA, were also examined individually. A series of linear regressions revealed that lower Time 1 self-esteem predicted an increase in direct aggression victimization from Time 1 to Time 2; however lower self-esteem at Time 1 was not found to be a significant predictor of increased electronic intrusiveness victimization at Time 2. Further, the reverse relations, with CDA victimization predicting self-esteem were not significant. These findings suggest adolescents low in self-esteem may be at increased risk for online direct aggression victimization. Implications, results for adolescents’ well-being, as well as prevention, intervention, and future directions are discussed

N2 fixation and cycling in Alnus glutinosa, Betula pendula and Fagus sylvatica woodland exposed to free air CO2 enrichment

We measured the effect of elevated atmospheric CO2 on atmospheric nitrogen (N2) fixation in the tree species Alnus glutinosa growing in monoculture or in mixture with the non-N2-fixing tree species Betula pendula and Fagus sylvatica. We addressed the hypotheses that (1) N2 fixation in A. glutinosa will increase in response to increased atmospheric CO2 concentrations, when growing in monoculture, (2) the impact of elevated CO2 on N2 fixation in A. glutinosa is the same in mixture and in monoculture and (3) the impacts of elevated CO2 on N cycling will be evident by a decrease in leaf δ15N and by the soil-leaf enrichment factor (EF), and that these impacts will not differ between mixed and single species stands. Trees were grown in a forest plantation on former agricultural fields for four growing seasons, after which the trees were on average 3.8 m tall and canopy closure had occurred. Atmospheric CO2 concentrations were maintained at either ambient or elevated (by 200 ppm) concentrations using a free-air CO2 enrichment (FACE) system. Leaf δ15N was measured and used to estimate the amount (Ndfa) and proportion (%Ndfa) of N derived from atmospheric fixation. On average, 62% of the N in A. glutinosa leaves was from fixation. The %Ndfa and Ndfa for A. glutinosa trees in monoculture did not increase under elevated CO2, despite higher growth rates. However, N2 fixation did increase for trees growing in mixture, despite the absence of significant growth stimulation. There was evidence that fixed N2 was transferred from A. glutinosa to F. sylvatica and B. pendula, but no evidence that this affected their CO2 response. The results of this study show that N2 fixation in A. glutinosa may be higher in a future elevated CO2 world, but that this effect will only occur where the trees are growing in mixed species stands