2,384 research outputs found

    EndoBarrier®: a safe and effective novel treatment for obesity and type 2 diabetes?

    No full text
    BACKGROUND AND AIMS: Obesity associated with diabetes mellitus is a significant worldwide problem associated with considerable health care costs. Whilst surgical intervention is effective, it is invasive, costly and associated with complications. This study aims to evaluate the safety and efficacy of the EndoBarrier®, a duodenal-jejunal sleeve bypass as an alternative treatment of diabetes mellitus in obese patients. MATERIALS AND METHODS: This was a multi-centre, non-randomised trial recruiting obese patients with type 2 diabetes from three sites in the UK. Eligible participants had a BMI of 30-50 kg/m2and HbA1c levels of 7.5-10%. The study comprised a 12-month period with the EndoBarrier® inserted and a 6-month follow-up period after it had been explanted. The primary study outcomes were weight, BMI, HbA1c levels and fasting insulin and glucose levels. RESULTS: Forty-five patients were recruited and 31 patients (69%) completed the 12-month study period. Significant reductions in weight (95%CI 0.62-29.38; p < 0.05) and BMI (95%CI 1.1-8.7; p < 0.005) were documented 12 months after device insertion. The mean HbA1c was significantly reduced (95%CI 0.1-1.6; p < 0.05) after the device insertion period and reductions in metabolic parameters (fasting insulin and glucose levels) were also documented during the study. Adverse events were also assessed in all patients, the vast majority of which were reported as mild. CONCLUSIONS: The EndoBarrier® appears to be a safe and effective treatment strategy in overweight patients with poor glycaemic control despite medical therapy, or in those who are eligible but decline bariatric surgery

    Thermotropic Behavior of Coconut Oil During Wheat Dough Mixing: Evidence for a Solid-Liquid Phase Separation According to Mixing Temperature

    Get PDF
    Freeze fracture electron microscopy and differential scanning calorimetry were used to study the behavior of coconut oil during cake batter processing. The greatest modifications of fat crystallization are due to the mixing temperature of batter more than the physical state of the fat before is incorporation and the wheat flour hydration. mixing at a temperature below the melting point of coconut oil involves a liquid/solid fat segregation in the cake batter. The endogenous wheat flour lipids and proteins appear to stabilize this fat partition. These results are likely related to previous observations which correlate loaf volume and mixing temperature of wheat flour dough containing coconut oil

    Importance of soil legacy effects and successful mutualistic interactions during Australian acacia invasions in nutrient-poor environments

    Get PDF
    1. Non-native plants often alter environments they invade, favouring their own performance through positive feedbacks. Plant–soil interactions represent one such mechanism, but their complexity (e.g. invader-induced changes in soil nutrients, microbial communities, etc.) makes inferences of the precise mechanisms that benefit invaders difficult. Here we aimed to determine: (1) whether invasion by Australian acacias (genus Acacia Mill.) changes nitrogen-fixing soil rhizobial community diversity and structure, and (2) the importance of available rhizobia and overall invader-induced soil changes as significant facilitators of acacia performance. 2. We sampled soils from various invaded and nearby uninvaded areas in South Africa’s Core Cape Subregion and, using next generation sequencing, compared rhizobial communities between invaded and univaded soils. We then determined the relative importance of soil status (invaded vs. uninvaded), in conjunction with rhizobial addition, to the performance of invasive acacias under common garden conditions. 3. Next generation sequencing data revealed that invaded soils generally harboured lower rhizobial diversity and were compositionally more homogenous compared to uninvaded soils. Bradyrhizobium strains, the most common known rhizobia associated with acacias, were more abundant in invaded than uninvaded sites. Our greenhouse experiment found significantly reduced growth performances of acacias in uninvaded relative to invaded soils for most species by site comparisons, and almost no influence of additional rhizobial inoculum. However, the overall relationship between nodulation and growth kinetics was much steeper for plants grown in uninvaded compared to invaded soils. 4. Despite invasive acacias homogenizing nitrogen-fixing rhizobial community composition and reducing diversity, it appears that mutualist availability poses no significant barrier to acacia establishment. Although acacia-induced changes to soil conditions enhance plant performance, successful nodulation seems important to early growth performance when encountering novel soil conditions. 5. Synthesis. We provide evidence that invasions by Australian acacias affect the diversity and structure of soil rhizobial communities. Although overall soil changes benefit their performance independent of rhizobia addition, forming successful mutualistic interactions is critical during the establishment phase under novel environmental conditions. Taken together, our results indicate that interactions between soil abiotic and biotic conditions work in concert to enhance invader performance through positive feedbacks

    Black Hole Scattering from Monodromy

    Full text link
    We study scattering coefficients in black hole spacetimes using analytic properties of complexified wave equations. For a concrete example, we analyze the singularities of the Teukolsky equation and relate the corresponding monodromies to scattering data. These techniques, valid in full generality, provide insights into complex-analytic properties of greybody factors and quasinormal modes. This leads to new perturbative and numerical methods which are in good agreement with previous results.Comment: 28 pages + appendices, 2 figures. For Mathematica calculation of Stokes multipliers, download "StokesNotebook" from https://sites.google.com/site/justblackholes/techy-zon

    The effects of a kappa-distribution in the heliosheath on the global heliosphere and ENA flux at 1 AU

    Full text link
    We investigate heliosheath energetic neutral atom (ENA) fluxes at keV energies, by assuming that the heliosheath proton distribution can be approximated by a kappa-distribution. The choice of the kappa parameter derives from observational data of the solar wind (SW). This has direct applications to the upcoming IBEX mission. We will look at all-sky ENA maps within the IBEX energy range (10 eV to 6 keV), as well as ENA energy spectra in several directions. We find that the use of kappa, as opposed to a Maxwellian, gives rise to greatly increased ENA fluxes above 1 keV, while medium energy fluxes are somewhat reduced. We show how IBEX data can be used to estimate the spectral slope in the heliosheath, and that the use of kappa reduces the differences between ENA maps at different energies. We also investigate the effect introducing a kappa-distribution has on the global interaction between the SW and the local interstellar medium (LISM), and find that there is generally an increase in energy transport from the heliosphere into the LISM, due to the modified profile of ENA's energies. This results in a termination shock that moves out by 4 AU, a heliopause that moves in by 9 AU and a bow shock 25 AU farther out, in the nose direction

    Structural Controls on Shallow Cenozoic Fluid Flow in the Otago Schist, New Zealand

    Get PDF
    The Otago Schist in the South Island of New Zealand represents an exhumed Mesozoic accretionary prism. Two coastal areas (Akatore Creek and Bruce Rocks) south of Dunedin preserve structural and geochemical evidence for the development of postmetamorphic hydrothermal systems that involved widespread fluid-rock reaction at shallow crustal depths. The Jurassic to Triassic pumpellyite-actinolite (Akatore Creek) to upper greenschist facies (Bruce Rocks) metamorphic fabrics were crosscut by sets of regionally extensive Cretaceous exhumation joints. Many of the joints were subsequently reactivated to form networks of small-displacement (<metres) strike-slip faults containing cemented fault breccias and veins composed of hydrothermal calcite, siderite, and ankerite. Paleostress analysis performed on infrequent fault slickenlines indicates an overall strike-slip paleostress regime and a paleo-σ1 orientation (azimuth 094°) similar to the contemporary σ1 orientation in Otago and Canterbury (azimuth c. 110°-120°). High δ18O values in vein calcite (δ18OVPDB=21 to 28‰), together with the predominance of Type I calcite twins, suggest that vein formation occurred at low temperatures (<200°C) in the shallow crust and was associated with strongly channelized fluid flow along the joint and fault networks. Mass-balance calculations performed on samples from carbonate alteration zones show that significant mobilisation of elements occurred during fluid flow and fluid-rock reaction. Whole-rock and in situ carbonate 87Sr/86Sr data indicate varying degrees of interaction between the hydrothermal fluids and the host rock schists. Fluids were likely derived from the breakdown of metamorphic Ca-rich mineral phases with low 87Rb in the host schists (e.g., epidote or calcite), as well as more radiogenic components such as mica. Overall, the field and geochemical data suggest that shallow fluid flow in the field areas was channelized along foliation surfaces, exhumation joints, and networks of brittle faults, and that these structures controlled the distribution of fluid-rock reactions and hydrothermal veins. The brittle fault networks and associated hydrothermal systems are interpreted to have formed after the onset of Early Miocene compression in the South Island and may represent the manifestation of fracturing and fluid flow associated with reverse reactivation of regional-scale faults such as the nearby Akatore Fault
    • …
    corecore