The effectiveness of an intervention to promote awareness and reduce online risk behavior in early adolescence

The current study explored the effect of a school-based intervention on online risk awareness and behavior in order to shed light on a relatively unexplored field with high practical relevance. More than 800 Belgium primary school children (grade 4 and 6) were assessed at two measurements (n T1 = 812, 51.2 % female; n T2 = 819, 51.3 % female) before and after the intervention. Half of them received a 10 min classroom intervention indicating online risks. Children in the control group received a 10 min presentation concerning online applications without any emphasis on risks. Children in the intervention group were more likely to be aware of online risks directly after the intervention; this effect was still noticeable 4 months after. Reporting of online risk behavior in the intervention group was also higher compared to the control group who did not receive the intervention. Overall online risk awareness and online risk behavior were negatively associated and the awareness did not modulate the association between the intervention and online risk behavior. Furthermore, individual differences were assessed. Girls were more likely to be aware of online risks and asserted less online risk behavior than boys were. In line with the imperative in adolescence to become more risk taking, children in a higher grade were more likely to behave in a risky manner when online. The current study provides a valuable starting point for further research on how to decrease online risk behavior in early adolescence. Keywords: School-based intervention, Internet, Online risk awareness, Online risk behavior, Early adolescenc

Self phase modulation in Highly nonlinear hydrogenated amorphous silicon

We study self phase modulation in submicron amorphous silicon-on-insulator waveguides. We extract both the real and imaginary part of the nonlinear parameter gamma from a 1 cm long waveguide with a cross-section of 500x220nm(2). The real and imaginary part of the nonlinear parameter are found to be 767W(-1)m(-1) and -28W(-1)m(-1) respectively. The figure of merit (FOM) is found to be 3.6 times larger than the FOM in crystalline silicon (c-Si)

DAC-Less amplifier-less generation and transmission of QAM signals using sub-volt silicon-organic hybrid modulators

We demonstrate generation and transmission of optical signals by directly interfacing highly efficient silicon-organic hybrid (SOH) modulators to binary output ports of a field-programmable gate array. Using an SOH Mach-Zehnder modulator (MZM) and an SOH IQ modulator we generate ON-OFF- keying and binary phase-shift keying signals as well as quadrature phase-shift keying and 16-state quadrature amplitude modulation (16QAM) formats. Peak-to-peak voltages amount to only 0.27 V-pp for driving the MZM and 0.41 V-pp for the IQ modulator. Neither digital-to-analog converters nor drive amplifiers are required, and the RF energy consumption in the modulator amounts to record-low 18 fJ/bit for 16QAM signaling