33 research outputs found

    Marine Heat Waves and the Influence of El Niño off Southeast Queensland, Australia

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    In this paper, we investigate the occurrence and spatial variability of marine heat waves (MHWs) off the southeast coast of Queensland, Australia. The focus is on identifying sea surface temperature (SST) variability in two key ecological hotspots located south of the Australian Great Barrier Reef. This coastal region is bordered in the east by the intensification zone of the East Australian Current (EAC). It includes Hervey Bay, which is part of a UNESCO declared marine biosphere and the Southeast Fraser Island Upwelling System. The analysis of remotely sensed SST for the period 1993 to 2016 identifies the largest number of MHW days for Hervey Bay with a mean length of 12 days. The maximum length of 64 days occurred during the austral summer 2005/2006. The years with the largest number of MHW days was found to occur following the El Niño events in 1998, 2010, and 2016. A cross-correlation and Empirical Orthogonal Function analysis identified a significant correlation with a time lag of 7 months between SST anomalies in the Niño 3.4 region and the southeast Queensland coast. 78% of variance in SST anomalies is explained by the first mode of variability. The strength of the relationship with El Niño was spatially variable and the weakest in Hervey Bay. Due to its sheltered location and shallowness, it is argued that local weather patterns and air-sea fluxes influence this area more than the other two regions, where remotely forced changes in oceanic heat advection may have a stronger impact on generating MHWs. Biodiverse coastal shelf ecosystems are already under tremendous pressure due to human activities. This is likely to be compounded by continued climatic change and an increasing number of MHWs. Thus, similar studies are encouraged for other regional shelfs and smaller scale coastal systems

    Diversität und Abundanz Moskito-übertragener Viren in Ghana, Westafrika

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    Diese Arbeit sollte einen Eindruck über die genetische Diversität an moskitoassoziierten Viren in Kumasi, Ghana, vermitteln. Daten hierzu lagen bisher nicht vor. Hierzu wurden an 26 Fangtagen im Februar und März 2011 insgesamt 1.622 Moskitos im Botanischen Garten und in einem Wohngebiet auf dem Campusgelände der Universität in Kumasi gefangen. Die Moskitos wurden soweit möglich bis zur Art bestimmt. Für die nachfolgenden Schritte wurden die Moskitos einzeln homogenisiert und anschließend in 20er Pools zu insgesamt 62 Pools zusammengefasst. Die Proben wurden zum einen mit generischen PCR-Assays auf Infektionen mit Flavi-, Bunya- Alpha- und Mesoniviren untersucht. Zum anderen wurde versucht in den Proben eventuell vorhandene infektiöse Viruspartikel in Zellkultur anzuzüchten. Es wurden 25 Moskitospezies, die zu 12 Genera gehören, gefangen. Dies entspricht 54% der bisher für Ghana beschriebenen Moskitospezies. Es wurden zwei bisher unbekannte insektenspezifische Flaviviren detektiert, die als Kumasi-ISF-A und Kumasi- ISF-B bezeichnet wurden. Kumasi-ISF-A wie auch Kumasi-ISF-B gruppieren mit insektenspezifischen Flaviviren, die aus Aedes Moskitos stammen. Außerdem wurden Stämme von Culex-Flavivirus nachgewiesen, welche bisher nur in Moskitos aus Asien, Amerika und Ostafrika gefunden wurden. Weiterhin wurden zwei bisher unbekannte insektenspezifische Phasiviren (Familie Phenuiviridae) in 25 Pools detektiert. Die Sequenzen wiesen untereinander eine genetische Distanz von 65 % auf und wurden als KNUST-Aedes Virus und KNUST-Culex Virus bezeichnet. Als weiteres Bunyavirus wurde Herbert Virus (Familie Peribunyaviridae, Genus Herbevirus) in sechs Pools nachgewiesen. Besonders hervorzuheben ist, dass aus allen 62 Pools infektiöse Viren in Moskitozellen isoliert werden konnten. Innerhalb der vorliegenden Arbeit konnte nicht herausgefunden werden um welche Viren es sich bei den Isolaten handelt. Da unterschiedliche cytopatische Effekte zu beobachten waren, ist davon auszugehen, dass verschiedene, bisher unbekannte Viren isoliert wurden. Die Ergebnisse dieser Arbeit zeigen, dass Moskitos aus Ghana mit einer Vielzahl an bisher unbekannten Viren infiziert sind. In dieser Arbeit konnten neue insektenspezifische Viren identifiziert werden. Inwiefern es sich bei den infektiösen Zellkulturüberständen um human- oder tierpathogene Viren handelt, ist Gegenstand weiterer Forschungsarbeiten

    Marine heat waves and the influence of El Nino off southeast Queensland, Australia

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    In this paper, we investigate the occurrence and spatial variability of marine heat waves (MHWs) off the southeast coast of Queensland, Australia. The focus is on identifying sea surface temperature (SST) variability in two key ecological hotspots located south of the Australian Great Barrier Reef. This coastal region is bordered in the east by the intensification zone of the East Australian Current (EAC). It includes Hervey Bay, which is part of a UNESCO declared marine biosphere and the Southeast Fraser Island Upwelling System. The analysis of remotely sensed SST for the period 1993 to 2016 identifies the largest number of MHW days for Hervey Bay with a mean length of 12 days. The maximum length of 64 days occurred during the austral summer 2005/2006. The years with the largest number of MHW days was found to occur following the El Niño events in 1998, 2010 and 2016. A cross-correlation and Empirical Orthogonal Function analysis identified a significant correlation with a time lag of seven months between SST anomalies in the Niño 3.4 region and the southeast Queensland coast. 78% of variance in SST anomalies is explained by the first mode of variability. The strength of the relationship with El Niño was spatially variable and the weakest in Hervey Bay. Due to its sheltered location and shallowness, it is argued that local weather patterns and air-sea fluxes influence this area more than the other two regions, where remotely forced changes in oceanic heat advection may have a stronger impact on generating MHWs. Biodiverse coastal shelf ecosystems are already under tremendous pressure due to human activities. This is likely to be compounded by continued climatic change and an increasing number of MHWs. Thus, similar studies are encouraged for other regional shelfs and smaller scale coastal systems

    A randomized trial on effectiveness of artemether-lumefantrine versus artesunate plus amodiaquine for unsupervised treatment of uncomplicated Plasmodium falciparum malaria in Ghanaian children

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    <p>Abstract</p> <p>Background</p> <p>Numerous trials have demonstrated high efficacy and safety of artemisinin-based combination therapy (ACT) under supervised treatment. In contrast, effectiveness studies comparing different types of ACT applied unsupervised are scarce. The aim of this study was to compare effectiveness, tolerability and acceptance of artesunate plus amodiaquine (ASAQ) against that of artemether-lumefantrine (AL) in Ghanaian children with uncomplicated <it>Plasmodium falciparum </it>malaria.</p> <p>Methods</p> <p>A randomized open-label trial was conducted at two district hospitals in the Ashanti region, Ghana, an area of intense malaria transmission. A total of 246 children under five years of age were randomly assigned to either ASAQ (Arsucam<sup>®</sup>) or AL (Coartem<sup>®</sup>). Study participants received their first weight-adjusted dose under supervision. After the parent/guardian was advised of times and mode of administration the respective three-day treatment course was completed unobserved at home. Follow-up visits were performed on days 3, 7, 14 and 28 to evaluate clinical and parasitological outcomes, adverse events, and haematological recovery. Length polymorphisms of variable regions of <it>msp1 </it>and <it>msp2 </it>were determined to differentiate recrudescences from reinfections. Acceptance levels of both treatment regimens were assessed by means of standardized interviews.</p> <p>Results</p> <p>Adequate clinical and parasitological responses after AL and ASAQ treatment were similar (88.3% and 91.7%, respectively). Interestingly, more late clinical failures until day 28 occurred in AL-treated children than in those who received ASAQ (17.5% and 7.3%, respectively; Hazard Ratio 2.41, 95% CI 1.00–5.79, p < 0.05).</p> <p>Haematological recovery and drug tolerability were not found to be significantly different in both study arms. The acceptance of treatment with ASAQ was higher than that with AL (rank-scores 10.6 and 10.3, respectively; p < 0.05).</p> <p>Conclusion</p> <p>Unobserved AL and ASAQ treatment showed high adequate clinical and parasitological responses, though AL was inferior in preventing late clinical failures.</p

    Phase evolution of C-(N)-A-S-H/N-A-S-H gel blends investigated via alkali-activation of synthetic calcium aluminosilicate precursors

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    Stoichiometrically-controlled alkali-activated pastes containing calcium-(sodium) aluminosilicate hydrate (C-(N)-A-S-H) and sodium aluminosilicate hydrate (N-A-S-H) gels are produced by alkali-activation of high-purity synthetic calcium aluminosilicate powders. These powders are chemically comparable to the glass in granulated blast furnace slag, but without interference from minor constituents. The physiochemical characteristics of these gels depend on precursor chemical composition. Increased Ca content of the precursor promotes formation of low-Al, high-Ca C-(N)-A-S-H with lower mean chain length as determined by quantification of solid state nuclear magnetic resonance spectra, and less formation of calcium carboaluminate ‘Alumino-ferrite mono’ (AFm) phases. Increased Al content promotes Al inclusion and reduced crosslinking within C-(N)-A-S-H, increased formation of calcium carboaluminate AFm phases, and formation of an additional N-A-S-H gel. Small changes in precursor composition can induce significant changes in phase evolution, nanostructure and physical properties, providing a novel route to understand microstructural development in alkali-activated binders and address key related durability issues

    Oncoplastic breast surgery: A guide to good practice

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    Oncoplastic Breast Surgery has become standard of care in the management of Breast. Cancer Patents. These guidelines written by an Expert Advisory Group; convened by the Association of Breast Surgery (ABS) and the British Association of Plastic, Reconstructive and Aesthetic Surgeons (BAPRAS), are designed to provide all members of the breast cancer multidisciplinary team (MDT) with guidance on the best breast surgical oncoplastic and reconstructive practice at each stage of a patient's journey, based on current evidence. It is hoped they will also be of benefit to the wide range of professionals and service commissioners who are involved in this area of clinical practice

    Solid-state nuclear magnetic resonance spectroscopy of cements

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    Cement is the ubiquitous material upon which modern civilisation is built, providing long-term strength, impermeability and durability for housing and infrastructure. The fundamental chemical interactions which control the structure and performance of cements have been the subject of intense research for decades, but the complex, crystallographically disordered nature of the key phases which form in hardened cements has raised difficulty in obtaining detailed information about local structure, reaction mechanisms and kinetics. Solid-state nuclear magnetic resonance (SS NMR)spectroscopy can resolve key atomic structural details within these materials and has emerged as a crucial tool in characterising cement structure and properties. This review provides a comprehensive overview of the application of multinuclear SS NMR spectroscopy to understand composition–structure–property relationships in cements. This includes anhydrous and hydrated phases in Portland cement, calcium aluminate cements, calcium sulfoaluminate cements, magnesia-based cements, alkali-activated and geopolymer cements and synthetic model systems. Advanced and multidimensional experiments probe 1 H, 13 C, 17 O, 19 F, 23 Na, 25 Mg, 27 Al, 29 Si, 31 P, 33 S, 35 Cl, 39 K and 43 Ca nuclei, to study atomic structure, phase evolution, nanostructural development, reaction mechanisms and kinetics. Thus, the mechanisms controlling the physical properties of cements can now be resolved and understood at an unprecedented and essential level of detail

    Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

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    Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe

    Native pastures and beef cattle show a spatially variable response to a changing climate in Queensland, Australia

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    Queensland's rangelands are an important source for Australia's pastoral food production. However, they are subject to significant climate variability and will be under increasing pressure as the climate changes, potentially leading to loss of productivity. Pasture growth fluctuates greatly due to rainfall variability, which unfortunately is the climate variable with the largest uncertainties in future projections for northern and eastern Australia. This sensitivity study examines the effect of climate change and its interaction with soil fertility and trees on pasture and livestock production in Queensland. Nine climate change sensitivities were tested in various combinations; an increase in air temperatures by a median projected value of +3 °C, rainfall changes of -20 %, -10 % and +10 % and an increase of carbon dioxide concentrations to 700 ppm. The GRASP model was used to assess the responses of pasture growth, pasture quality and cattle liveweight change per head. The most arid areas in western and south-western Queensland were the most sensitive to changes in rainfall. In contrast, the tropical north was the most resilient region. Southern and south-eastern Queensland benefitted from higher air temperatures producing greater pasture growth, quality and liveweight gain per head by extending the growing season and reducing frost during the winter months. The presence of trees competing for water and nitrogen increased the sensitivity of pasture to climate change, especially at higher carbon dioxide levels and lower rainfall. Increased carbon dioxide enhanced pasture growth and mitigated rainfall reductions by improving the water use efficiency of the plants. Thus, a warmer climate may create new opportunities in the south and south-east, but a warmer and drier climate in the western regions of Queensland is likely to reduce pasture and livestock production
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