384 research outputs found

    The rotation-magnetic field relation

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    Today, the generation of magnetic fields in solar-type stars and its relation to activity and rotation can coherently be explained, although it is certainly not understood in its entirety. Rotation facilitates the generation of magnetic flux that couples to the stellar wind, slowing down the star. There are still many open questions, particularly at early phases (young age), and at very low mass. It is vexing that rotational braking becomes inefficient at the threshold to fully convective interiors, although no threshold in magnetic activity is seen, and the generation of large scale magnetic fields is still possible for fully convective stars. This article briefly outlines our current understanding of the rotation-magnetic field relation.Comment: 8 pages, splinter summary of the session "The rotation-magnetic field relation" at Cool Stars 15 in St Andrew

    The ICDP Lake Bosumtwi Drilling Project: A First Report

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    The 10.5 -km-diameter, 1.07-Ma Bosumtwi impact crater was the subject of a multi-disciplinary and international drilling effort of the International Continental Scientific Drilling Program (ICDP) from July to October 2004. Sixteen different holes were drilled at six locations within the lake, to a maximum depth of 540 m. A total of about 2.2 km of core material was obtained. Despite some technical and logistical challenges, the project has been very successful and it is anticipated that the first scientific results will be available in late 2005

    Neural evidence for "intuitive prosecution": The use of mental state information for negative moral verdicts

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    Moral judgment depends critically on theory of mind (ToM), reasoning about mental states such as beliefs and intentions. People assign blame for failed attempts to harm and offer forgiveness in the case of accidents. Here we use fMRI to investigate the role of ToM in moral judgment of harmful vs. helpful actions. Is ToM deployed differently for judgments of blame vs. praise? Participants evaluated agents who produced a harmful, helpful, or neutral outcome, based on a harmful, helpful, or neutral intention; participants made blame and praise judgments. In the right temporo-parietal junction (right TPJ), and, to a lesser extent, the left TPJ and medial prefrontal cortex, the neural response reflected an interaction between belief and outcome factors, for both blame and praise judgments: The response in these regions was highest when participants delivered a negative moral judgment, i.e., assigned blame or withheld praise, based solely on the agent's intent (attempted harm, accidental help). These results show enhanced attention to mental states for negative moral verdicts based exclusively on mental state information.Athinoula A. Martinos Center for Biomedical ImagingSimons FoundationNational Science Foundation (U.S.)John Merck Scholars Progra

    Do on-farm natural, restored, managed and constructed wetlands mitigate agricultural pollution in Great Britain and Ireland?: a systematic review

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    Wetlands in agricultural landscapes offer a number of benefits to the landscape function in which they are set, reducing nutrient runoff, providing additional habitat mosaics and offering various ecosystem services. They require careful planning and maintenance in order to perform their optimum design function over a prolonged period of time. They should be treated as functional units of farm infrastructure rather than fit-and-forget systems. A high priority topic within the Department for Environment, Food and Rural Affairs (DEFRA) water quality programme is the mitigation of pollution from agriculture. This programme was set up to meet the requirements of the European Water Framework Directive (WFD) EU (2000). Nutrient loss from agricultural land has been suggested as a major cause of elevated nutrient concentrations in surface waters in the UK. Nitrogen (N) and phosphorus (P) are of particular concern as an excess of either nutrient can lead to eutrophication of freshwater systems and coastal waters. Agriculture has also been identified as a significant source of suspended sediment (SS) concentrations in UK rivers and agriculturally derived sediment has been identified as a source of increased bed-sediment P concentrations in rivers. High bed sediments loads have other negative impacts, such as clogging river gravels reducing fish spawning. There is considerable evidence in the published and grey literature that wetlands have the ability to remove nutrients and sediment and thus reduce the load on receiving waters. Wetlands have also been reported to perform other ecosystem services, such as reducing floods, supporting biodiversity and sequestering carbon. A policy to promote the conservation, management, restoration or construction of wetlands could help to mitigate the impacts of N, P and SS from agriculture delivering requirements of WFD through Catchment Sensitive Farming following an Ecosystem Approach and Catchment Based Approach promoted by Defra. It could also meet other commitments such as implementing the Ramsar and Biodiversity Conventions to which the UK is a signatory. However, the term wetlands covers a wide range of habitat types and it is important that policy makers are provided with accurate, robust and independently reviewed information on the degree to which different types of wetland perform these services under different circumstances, so that policy can most best targeted. This systematic review assesses the available evidence on the performance of various wetland types on farms to reduce nutrient input and suspended sediments to receiving waters. It provides a defensible evidence base on which to base policy. The studies reviewed cover different input loads and the analysis compares performance of these wetland systems in respect of % reduction efficiency. In England and Wales, Defra, working closely with the Environment Agency and Natural England, has commissioned this systematic review on how effective, and what influences the effectiveness of wetlands at mitigating N, P and SS inputs from agriculture to receiving freshwater in the United Kingdom and Ireland
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