Low-crosstalk bifurcation detectors for coupled flux qubits

We present experimental results on the crosstalk between two AC-operated dispersive bifurcation detectors, implemented in a circuit for high-fidelity readout of two strongly coupled flux qubits. Both phase-dependent and phase-independent contributions to the crosstalk are analyzed. For proper tuning of the phase the measured crosstalk is 0.1 % and the correlation between the measurement outcomes is less than 0.05 %. These results show that bifurcative readout provides a reliable and generic approach for multi-partite correlation experiments.Comment: Copyright 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters and may be found at http://link.aip.org/link/?apl/96/12350

Phase relations in the Ag-Fe-Ti system at 1123 K

Abstract Phase equilibria in the Ag-Fe-Ti system at 1123 K were determined by using polyphase diffusion couples and equilibrated alloys. The experimental observations are in agreement with a thermodynamic evaluation performed on this system. No ternary phases are present on the Ag-Fe-Ti isotherm at 1123 K. The solubility of iron in the binary intermetallic compounds Ti2Ag and TiAg as well as the solubility of silver in FezTi are negligible. The maximum silver content in FeTi was estimated as =0.5 at.%, while nearly 6 at.% of silver can be dissolved in the /3-Ti(Fe) based solid solution at this temperature

Adaptation of Bordetella pertussis to vaccination: a cause for its reemergence?

In the Netherlands, as in many other western countries, pertussis vaccines have been used extensively for more than 40 years. Therefore, it is conceivable that vaccine-induced immunity has affected the evolution of Bordetella pertussis. Consistent with this notion, pertussis has reemerged in the Netherlands, despite high vaccination coverage. Further, a notable change in the population structure of B. pertussis was observed in the Netherlands subsequent to the introduction of vaccination in the 1950s. Finally, we observed antigenic divergence between clinical isolates and vaccine strains, in particular with respect to the surface-associated proteins pertactin and pertussis toxin. Adaptation may have allowed B. pertussis to remain endemic despite widespread vaccination and may have contributed to the reemergence of pertussis in the Netherlands

GeSn/Ge heterostructure short-wave infrared photodetectors on silicon

status: publishe

Working with parents to counteract bullying:A randomized controlled trial of an intervention to improve parent-school cooperation

This study examined the effectiveness of an intervention aimed at improving parent-school cooperation in counteracting bullying. Using a randomized controlled trial, data of teachers, parents of non-victimized children, and children themselves were collected at 13 intervention and 14 control schools (grades 3-6, N at post-assessment: teachers = 83, parents = 153, children = 2,510) at two time points (time lag about 6 months). Results showed positive effects of the intervention for some aspects of the primary outcomes: parents' and teachers' attitudes and efforts, whereas no effects were found of teachers' or parents' competences in counteracting bullying. No intervention effects were found for secondary outcomes: children's self-reported bullying, victimization, well-being, and self-esteem. The findings indicate that, due to the intervention, teachers and parents were more aligned and able to cooperate, even within the short time of the intervention: one school year. This is the first essential step to systematically addressing parents' role in tackling bullying; future research is needed to examine the long-term effects of parent and school interventions in enhancing the effectiveness of anti-bullying programs.</p

State-of-the-Art Instrumentation Package to Support Model Organism Research in Space

Hardware was developed for the Ames student Fruit-Fly Experiment (AFEx) to support fly growth and analysis during spaceflight. The hardware consists of a 1.5U vented aluminum box that houses an acrylic habitat, video camera, LED lighting, and environmental sensors. Power is provided via two USB connectors, one of which also supports data downlink. While the hardware was designed for use with fruit flies, it will house plants on an upcoming mission and could be adapted for use with other systems