504 research outputs found

    Chemical information matters: an e-Research perspective on information and data sharing in the chemical sciences

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    Recently, a number of organisations have called for open access to scientific information and especially to the data obtained from publicly funded research, among which the Royal Society report and the European Commission press release are particularly notable. It has long been accepted that building research on the foundations laid by other scientists is both effective and efficient. Regrettably, some disciplines, chemistry being one, have been slow to recognise the value of sharing and have thus been reluctant to curate their data and information in preparation for exchanging it. The very significant increases in both the volume and the complexity of the datasets produced has encouraged the expansion of e-Research, and stimulated the development of methodologies for managing, organising, and analysing "big data". We review the evolution of cheminformatics, the amalgam of chemistry, computer science, and information technology, and assess the wider e-Science and e-Research perspective. Chemical information does matter, as do matters of communicating data and collaborating with data. For chemistry, unique identifiers, structure representations, and property descriptors are essential to the activities of sharing and exchange. Open science entails the sharing of more than mere facts: for example, the publication of negative outcomes can facilitate better understanding of which synthetic routes to choose, an aspiration of the Dial-a-Molecule Grand Challenge. The protagonists of open notebook science go even further and exchange their thoughts and plans. We consider the concepts of preservation, curation, provenance, discovery, and access in the context of the research lifecycle, and then focus on the role of metadata, particularly the ontologies on which the emerging chemical Semantic Web will depend. Among our conclusions, we present our choice of the "grand challenges" for the preservation and sharing of chemical information

    Water Rights and Water Allocation: Issues and Challenges for Asia

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    The primary audience for this report is management and staff working in water resources agencies in Asia, particularly those in river basin organizations (RBOs) in their various forms. The roles and responsibilities of RBOs vary considerably and are evolving as pressureson water resources are becoming more severe. Although this report seeks to share knowledge about the fundamentals and application of waterrights and allocation, it attempts to do so with a practical focus

    Scientific and technical data sharing: a trading perspective

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    It is arguably a precept that the open sharing of data maximises the scientific utility of the research that generated that data. Indeed, progress depends on individual scientists being able to build on the results produced by others. The means to facilitate sharing undoubtedly exist, but various studies have identified reluctance among researchers to share information with their peers, at least until the professional priorities of the original researchers have been accommodated. With a view to encouraging less inhibited collaboration, we appraise the processes of data exchange from the perspective of a trading environment and consider how data exchanges might promote (or perhaps hinder) collaboration in data-rich scientific research disciplines and how such an exchange might be set up. We suggest an exchange with trusted brokers (akin to the commodity markets) as a way to overcome the challenges of the current environment. We conclude by encouraging the scientific and technical community to debate the merits of a trading perspective on data sharing and exchange

    GENDER DIFFERENCES IN CHANGE OF DIRECTION MANEUVERS WITH LONG AXIS ROTATION: A PRELIMINARY INVESTIGATION

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    Females seem to have a greater predisposition to knee injuries than males (Harmon & Ireland, 2000). One extrinsic factor may be the cutting technique in a turn with long axis rotation, a movement that leaves an individual prone to knee injury. Thirty-six male and twenty female college athletes performed maximal effort changes in direction at 90 and 180 degrees. Different vertical and shear ground reaction forces were found between genders. When comparing data by gender and condition differences were found between the 900 and 1800 turns for all variables. More important, gender and condition interaction effects were found. Females exhibited greater relative vertical and anteroposterior braking forces with increased long axis rotation. Gender differences in ground reaction forces may suggest differences in technique which may be associated with increased injury risk

    Rivers of the Anthropocene Phase 1: A Comparative Study of the Tyne and Ohio River Valleys

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    poster abstractThe Rivers of the Anthropocene project is an international effort. Our part is an attempt to determine flood frequency and land use by American Indian tribes of the Mississippian Culture along the Ohio River. Methodologically, we will measure the physical and geochemical properties of lacustrine sediments recovered from Hovey Lake, a flood plane lake located on the Ohio River in southwestern Indiana. Sediment cores taken from Hovey Lake are being measured for bulk density and loss-on-ignition tests to determine organic composition by weight. Magnetic susceptibility is also being measured to determine variations in the delivery of terrestrial material (e.g. from flooding/land erosion) to the lake. Land use will be evaluated by measuring variations in the elemental abundance and isotopic composition of nitrogen and organic carbon, which has been used in the past to identify prehistoric land use. Here we present the initial results of our ongoing work, including sedimentological and chronological data. Ultimately, these data will help bring together historical records, geochemical records, and other contributions from scientists around the world in our attempt to better understand mankind’s impact on our environment

    Tunable Feshbach resonances in collisions of ultracold molecules in 2ÎŁ^2\Sigma states with alkali-metal atoms

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    We consider the magnetically tunable Feshbach resonances that may exist in ultracold mixtures of molecules in 2ÎŁ^2\Sigma states and alkali-metal atoms. We focus on Rb+CaF as a prototype system. There are likely to be Feshbach resonances analogous to those between pairs of alkali-metal atoms. We investigate the patterns of near-threshold states and the resonances that they cause, using coupled-channel calculations of the bound states and low-energy scattering on model interaction potentials. We explore the dependence of the properties on as-yet-unknown potential parameters. There is a high probability that resonances will exist at magnetic fields below 1000 G, and that these will be broad enough to control collisions and form triatomic molecules by magnetoassociation. We consider the effect of CaF rotation and potential anisotropy, and conclude that they may produce additional resonances but should not affect the existence of rotation-free resonances

    Water-Food-Energy Nexus

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    The proposed SDGs on water, food and energy security all include targets on increasing efficiencies. Yet the water–food–energy nexus has multiple dimensions that, if managed in isolation, will compromise a nation’s ability to achieve the full portfolio of SDGs. Climate change introduces additional uncertainties, further increasing tensions between sectors for access to water. Conventional energy and food production are emitters of greenhouse gases, but measures to reduce emissions—including renewable energy interventions, such as subsidies for biofuel production—can have adverse consequences on food prices. To achieve desirable and sustainable outcomes for water, food, and energy requires investigating these elements as an integrated whole, across sectors and scales. The nexus approach is part of broader systems thinking; it features a pragmatic focus on the relatively limited number of policy choices that are constrained by political realities. This approach recognizes and minimizes trade-offs, builds synergies, and increases resource use efficiencies

    Tunable Feshbach resonances in collisions of ultracold molecules in 2ÎŁ states with alkali-metal atoms

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    We consider the magnetically tunable Feshbach resonances that may exist in ultracold mixtures of molecules in 2ÎŁmstates and alkali-metal atoms. We focus on Rb +CaF as a prototype system. There are likely to be Feshbach resonances analogous to those between pairs of alkali-metal atoms. We investigate the patterns of near-threshold states and the resonances that they cause, using coupled-channel calculations of the bound states and low-energy scattering on model interaction potentials. We explore the dependence of the properties on as-yet-unknown potential parameters. There is a high probability that resonances will exist at magnetic fields below 1000 G, and that these will be broad enough to control collisions and form triatomic molecules by magnetoassociation. We consider the effects of CaF rotation and anisotropy of the interaction potential, and conclude that they may produce additional resonances but should not affect the existence of rotation-free resonances

    Making molecules by mergoassociation: two atoms in adjacent nonspherical optical traps

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    Mergoassociation of two ultracold atoms to form a weakly bound molecule can occur when two optical traps that each contain a single atom are merged. Molecule formation occurs at an avoided crossing between a molecular state and the lowest motional state of the atom pair. We develop the theory of mergoassociation for pairs of nonidentical nonspherical traps. We develop a coupled-channel approach for the relative motion of the two atoms and present results for pairs of cylindrically symmetrical traps as a function of their anisotropy. We focus on the strength of the avoided crossing responsible for mergoassociation. We also develop an approximate method that gives insight into the dependence of the crossing strength on aspect ratio

    Making molecules by mergoassociation: Two atoms in adjacent nonspherical optical traps

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    Mergoassociation of two ultracold atoms to form a weakly bound molecule can occur when two optical traps that each contain a single atom are merged. Molecule formation occurs at an avoided crossing between a molecular state and the lowest motional state of the atom pair. We develop the theory of mergoassociation for pairs of nonidentical nonspherical traps. We develop a coupled-channel approach for the relative motion of the two atoms and present results for pairs of cylindrically symmetrical traps as a function of their anisotropy. We focus on the strength of the avoided crossing responsible for mergoassociation. We also develop an approximate method that gives insight into the dependence of the crossing strength on aspect ratio
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