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We present the first paleoseismic investigation of the Hyde Fault, one of a series of north-east striking reverse faults within the Otago range and basin province in southern New Zealand. Surface traces of the fault and associated geomorphology were mapped using a lidar digital elevation model and field investigations. Trenches were excavated at two sites across fault scarps on alluvial fan surfaces. The trenches revealed stratigraphic evidence for four surface-rupturing earthquakes. Optically stimulated luminescence dating constrains the timing of these events to around 47.2 ka (37.5–56.7 ka at 95% confidence), 34.6 ka (24.7–46.4 ka), 23.5 ka (19.7–27.3 ka) and 10.5 ka (7.9–13.1 ka). We obtain a mean inter-event time of 12.4 kyr (2.3–23.9 kyr at 95% confidence) and the slip rate is estimated to be 0.22 mm/yr (0.15–0.3 mm/yr). We do not find evidence to suggest that earthquake recurrence on the Hyde Fault is episodic, in contrast to other well-studied faults within Otago, suggesting diverse recurrence styles may co-exist in the same fault system. This poses challenges for characterising the seismic hazard potential of faults in the region, particularly when paleoearthquake records are limited to the most recent few events. [ABSTRACT FROM AUTHOR]

We present new Sr, Nd, Hf and Pb isotope data for Early Miocene shoshonitic and high-K lavas dredged from seamounts in the South Fiji Basin, southwest Pacific Ocean. Our analyses provide a useful reference dataset for this distinctive compositional suite. The shoshonitic lavas formed in an intra-oceanic back-arc basin setting and are broadly coeval with nearby arc and back-arc basin lavas. Further work in the region will be needed before the tectonic implications of the shoshonitic and high-K lavas are fully understood. [ABSTRACT FROM AUTHOR]

We analyse seismic data collected from a short-term array deployment in the low seismicity area of Dunedin city, New Zealand. The addition of this temporary network to the permanent GeoNet national seismic network allows detection of earthquakes not captured by the GeoNet network. Using one of the newly detected earthquakes as a master event, we employ a template match-filter analysis to identify similar events in the area. Specifically, we record a cluster of micro-events at the northern extent of the Akatore Fault (<15 km from the city centre). A recent paleoseismic study has shown the Akatore Fault to have had multiple earthquake ruptures in the late Holocene after over 110 ka of quiescence, so the observed microseismicity is consistent with the fault being in a state of elevated activity. In contrast, other known faults in the area are quiescent with respect to both microseismicity and Holocene ruptures. The establishment of a permanent seismic array in and around Dunedin for the monitoring of microseismicity on the Akatore Fault and other local faults is warranted. [ABSTRACT FROM AUTHOR]

Approximately 50% of new HIV infections in the US occur in teenagers, with African American females making up a disproportionate number. The purpose of this study was to identify factors that could encourage delaying sexual debut. Twenty-eight African American mothers and their early adolescent daughters were recruited from four inner-city community centers. Seven separate focus groups were conducted for mothers and daughters using principles of Participatory Action Research. Four codes emerged from the data: social norms regarding sex, males, self-esteem, and family structure. These codes support the importance of an intervention to facilitate sexual communication between a mother and her daughter. [ABSTRACT FROM AUTHOR]

African Americans make up the greater proportion of AIDS cases in adolescent girls but little is understood about the development of sexual risk behaviors during the early adolescent years. This article will explore ecological factors influencing adolescent sexual risk behaviors. In the focus groups, which were conducted using 28 African American mothers and their early adolescent daughters, 2 major themes emerged: exposure and support systems. Mothers described the impact community had on their daughters and how monitoring and support systems worked together to control exposure. The girls detailed the different ways they were impacted by the community. Attitudes the girls adopted from their exposures resulted in risk-taking behaviors or a determination to positively impact the community. Community was shown to be the context of the acquisition of sexual knowledge and attitudes. These findings support the development of interventions to address the impact of community on the participation of sexual risk behaviors. [ABSTRACT FROM AUTHOR]

This feature article describes the synthesis of various classes of monomers and polymers incorporating organoiron moieties. Poly-ethers incorporating η6-substituted-arcne-η5-cyclopentadienyliron moieties were synthesized via metal-mediated nucleophilic aromatic substitution reactions. Linear polymers incorporating both cationic and neutral organoiron units were prepared; these polymers underwent two electrochemical processes, oxidation of the neutral iron species occurred between 0.89 and 1.0V and reduction of the cationic iron groups occurred between -1.10 and -1.45 V. Polynorbomenes, polymethacrylates, and polystyrenes were prepared via radical and condensation polymerization of organoiron functionalized monomers. The incorporation of azo dyes into the polymers gave rise to a variety of colored materials that could be photobleached in the presence of hydrogen peroxide. The incorporation of benzothiazole-based dyes resulted in colored polymers with higher λmax values than azobenzene-based dyes, Photolytic decoordination of the cationic cyclopentadienyliron moieties resulted in the formation of organic analogs or neutral polyferrocenes depending on the nature of the starting polymers. A number of 3-arm star-shaped molecules were also prepared; electrochemical studies showed that the inner and outer iron moieties are reduced at different potentials. [ABSTRACT FROM AUTHOR]