Greenberger-Horne-Zeilinger-type and W-type entangled coherent states: Generation and Bell-type inequality tests without photon counting

We study Greenberger-Horne-Zeilinger-type (GHZ-type) and W-type three-mode entangled coherent states. Both types of entangled coherent states violate Mermin's version of the Bell inequality with threshold photon detection (i.e., without photon counting). Such an experiment can be performed using linear optics elements and threshold detectors with significant Bell violations for GHZ-type entangled coherent states. However, to demonstrate Bell-type inequality violations for W-type entangled coherent states, additional nonlinear interactions are needed. We also propose an optical scheme to generate W-type entangled coherent states in free-traveling optical fields. The required resources for the generation are a single-photon source, a coherent state source, beam splitters, phase shifters, photodetectors, and Kerr nonlinearities. Our scheme does not necessarily require strong Kerr nonlinear interactions; i.e., weak nonlinearities can be used for the generation of the W-type entangled coherent states. Furthermore, it is also robust against inefficiencies of the single-photon source and the photon detectors.

Improving family functioning and child outcome in methadone maintained families: the Parents Under Pressure programme

Twelve families responded to posters displayed in a methadone clinic for inclusion in a pilot study assessing the viability and potential utility of an intensive, multi-component family-focused intervention, the Parents Under Pressure programme. The programme was designed to improve child behaviour, decrease parental stress and improve family functioning in methadone-maintained families by targeting affect regulation, mood, views of self as a parent, drug use and parenting skills. Nine of the families completed the programme delivered in their homes; eight were recontacted at 3 months. Each family reported significant improvements in three domains: parental functioning, parent - child relationship and parental substance use and risk behaviour. In addition to the changes in family functioning, the majority of families reported a decrease in concurrent alcohol use, HIV risk-taking behaviour and maintenance dose of methadone. The families reported high levels of satisfaction with the programme. It is recommended that future studies include independent measures (e.g. behavioural observations) of child outcome and parental functioning. The results were optimistic and provided the impetus to evaluate the treatment programme using a randomized controlled trial.

Measuring community strength and social capital

In 2001/02 five case study communities in both metropolitan and regional urban locations in Australia were chosen as test sites to develop measures of community strength on four domains: natural capital; produced economic capital; human capital; and social and institutional capital. Secondary data sources were used to develop measures on the first three domains. For the fourth domain social and institutional capital primary data collection was undertaken through sample surveys of households. A structured approach was devised. This involved developing a survey instrument using scaled items relating to four elements: formal norms; informal norms; formal structures; and informal structures which embrace the concepts of trust, reciprocity, bonds, bridges, links and networks in the interaction of individuals with their community inherent in the notion social capital. Exploratory principal components analysis was used to identify factors that measure those aspects of social and institutional capital, with confirmatory analysis conducted using Cronbach's Alpha. This enabled the construction of four primary scales and 15 sub-scales as a tool for measuring social and institutional capital. Further analyses reveals that two measures anomie and perceived quality of life and wellbeing relate to certain primary scales of social capital.

Three separable domains regulate GTP-dependent association of H-ras with the plasma membrane

The microlocalization of Ras proteins to different microdomains of the plasma membrane is critical for signaling specificity. Here we examine the complex membrane interactions of H-ras with a combination of FRAP on live cells to measure membrane affinity and electron microscopy of intact plasma membrane sheets to spatially map microdomains. We show that three separable forces operate on H-ras at the plasma membrane. The lipid anchor, comprising a processed CAAX motif and two palmitic acid residues, generates one attractive force that provides a high-affinity interaction with lipid rafts. The adjacent hypervariable linker domain provides a second attractive force but for nonraft plasma membrane microdomains. Operating against the attractive interaction of the lipid anchor for lipid rafts is a repulsive force generated by the N-terminal catalytic domain that increases when H-ras is GTP loaded. These observations lead directly to a novel mechanism that explains how H-ras lateral segregation is regulated by activation state: GTP loading decreases H-ras affinity for lipid rafts and allows the hypervariable linker domain to target to nonraft microdomains, the primary site of H-ras signaling.