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We investigate gas hydrate formation processes in compressional, extensional and un-faulted settings on New Zealand's Hikurangi margin using seismic reflection data. The compressional setting is characterized by a prominent subduction wedge thrust fault that terminates beneath the base of gas hydrate stability, as determined from a bottom-simulating reflection (BSR). The thrust is surrounded by steeply dipping strata that cross the BSR at a high angle. Above the BSR, these strata are associated with a high velocity anomaly that is likely indicative of relatively concentrated, and broadly distributed, gas hydrates. The un-faulted setting—sedimentary infill of a slope basin on the landward side of a prominent thrust ridge—is characterized by a strong BSR, a thick underlying free gas zone, and short positive polarity reflection segments that extend upward from the BSR. We interpret the short reflection segments as the manifestation of gas hydrates within relatively coarse-grained sediments. The extensional setting is a localized, shallow response to flexural bending of strata within an anticline. Gas has accumulated beneath the BSR in the apex of folding. A high-velocity zone directly above the BSR is probably mostly lithologically-derived, and only partly related to gas hydrates. Although each setting shows evidence for focused gas migration into the gas hydrate stability zone, we interpret that the compressional tectonic setting is most likely to contain concentrated gas hydrates over a broad region. Indeed, it is the only setting associated with a deep-reaching fault, meaning it is the most likely of the three settings to have thermogenic gas contributing to hydrate formation. Our results highlight the importance of anisotropic permeability in layered sediments and the role this plays in directing sub-surface fluid flow, and ultimately in the distribution of gas hydrate. Each of the three settings we describe would warrant further investigation in any future consideration of gas hydrates as an energy resource on the Hikurangi margin. [ABSTRACT FROM AUTHOR]

Hollow and flexible crosslinked microcapsules of soybean protein, 150–300 μm in diameter, were produced using a modified solvent evaporation method. A maximum plasma absorption of approximately 2000% was obtained. At this swelling rate though, microcapsules bursting was initiated. Thus, the effective absorption capacity may not exceed 1700%. The observed presence of residual unreacted protein inside the microcapsules, was believed to be the main osmotic driving force, to which the extensive swelling and eventual bursting of the microcapsules may be attributed. Thermal analysis of the microcapsules revealed their amorphous nature, as opposed to the significantly crystalline nature of the original protein. [Copyright &y& Elsevier]

Background: Metered-dose inhaler (MDI) medications are frequently prescribed for the management of asthma in children. Because the use of inhalers can be difficult, many children with asthma fail to use their MDI correctly.Objective: The purpose of this study was to determine whether a specialized Pediatric Asthma Compliance and Technique (PACT) clinic could be effective in improving techniques for MDI use among children with asthma.Methods: Children referred to the PACT clinic underwent pulmonary testing and were asked to demonstrate their MDI technique at an initial coaching session. Clinicians at the PACT clinic demonstrated and reviewed correct techniques for MDI use and asked the children to demonstrate the technique again. Follow-up visits of at least 1/2 hour were scheduled according to the patient's asthma severity.Results: Of the 40 children referred to the PACT clinic, 26 were using an MDI at the time of their initial clinic assessment. Only 12% (3/26) were able to perform all 8 steps for MDI administration correctly (median 4 of 8 steps performed correctly without prompting). After the first coaching session, patients were followed up an average of 2.4 months later, with 31% (8/26) performing all 8 steps correctly. On average, children were able to perform 7 of 8 steps correctly without prompting. When the data were analyzed by step, statistically significant improvements were noted on 5 specific steps.Conclusions: The proper use of the MDI is crucial for the delivery of many asthma medications. The results of this study suggest that children need intensive education before they can learn and remember how to use their MDI correctly. One intensive coaching session on correct use of MDIs dramatically improved technique at follow-up in this inner-city medical clinic. [ABSTRACT FROM AUTHOR]

Abstract: Australia and New Zealand share in part a history in the Gondwana supercontinent. Australia has a long and complex tectonic history with the last major accretion in the early Paleozoic, whereas New Zealand is still undergoing major plate boundary processes. The Australian continent is relatively well covered with both active and passive seismic techniques. Multiple sources of information are therefore available for building a model of Moho depth. Results from on-shore and off-shore refraction experiments are supplemented by receiver functions from a large number of portable stations and the recently augmented set of permanent stations. Moho picks from more than 10500km of full-crustal reflection profiles provide valuable additional constraints. The composite data set provides good sampling of much of Australia, though coverage remains low in some remote desert areas. The various datasets provide multiple estimates of the depth to Moho in many regions, and the consistency between the different techniques is high. Some of the thinnest crust lies beneath the Archean craton in the Pilbara, and in the neighbourhood of the Simpson desert. Thick crust is encountered beneath parts of the Proterozoic in Central Australia, and beneath the Paleozoic Lachlan fold belt in southeastern Australia. There are a number of zones of sharp contrast in depth to Moho, notably in the southern part of Central Australia. Despite most of the continental material around New Zealand being submerged, Moho data for this region is mainly onshore concentrating on the Australia–Pacific plate boundary. Two major wide-angle reflection transects provide the bulk of the active source data with just a few traditional reflection profiles offshore. The plate boundary provides an abundance of local earthquakes for tomographic imaging and this data is supplemented with receiver functions from both portable and permanent networks. Onshore the combined coverage is as dense as that of Australia, although it could be argued that a higher spatial resolution is required to capture the nature of the Moho of tectonically active New Zealand. Three regions of thickened crust can be identified, one beneath the Southern Alps, another beneath Fiordland, and below the Wanganui Basin between the North and South Island. Thin crust is identified west of the volcanic arc, with extensive underplating below the back-arc region. [Copyright &y& Elsevier]

Embryo development is a dynamic process, determined by both the genetic background of the organism and the environment in which it develops. Environmental alterations during an organism's embryogenesis may induce changes in the development of some physiological regulatory systems, thereby causing permanent phenotypic changes in the embryo. The present study aimed to assess the effect of 17% O2 concentration during chorioallantoic membrane (CAM) development on a) CAM development, b) cardiovascular parameters, and c) embryo development postexposure and up to hatch. Two replicated trials, each with 840 fertile Cobb eggs, were conducted. At embryonic d 5 (E5) eggs were divided into 2 treatments: 1) control, and 2) 17% O2 concentration for 12 h/d from E5 through E12 (12H). The 12H embryos exhibited a clear and significant increase in the vascular area of the CAM, which grew to 6.8% larger than that of the control. Hematocrit and hemoglobin levels, as measured on E13 and E14, increased in response to the hypoxic treatments, but these differences were not maintained subsequently. Heart rate and relative heart weight were not affected by hypoxic exposure, but eggshell temperature in the 12H treatment was higher than that of the control, indicating higher heat production, which is consistent with the elevated plasma concentrations of triiodothyronine and thyroxin and with the enhanced oxygen consumption and residual yolk intake rate that followed exposure to hypoxic conditions. These findings indicate that embryos adapted to hypoxic condition enhance angiogenesis processes, which subsequently increase their blood oxygen-carrying capacity, enabling the increase of oxygen consumption, which positively affects their growth development and maturation compared with the control embryos. Such alterations may affect posthatch performance and the ability of broilers cardiovascular system to meet elevated oxygen demand. [ABSTRACT FROM AUTHOR]