943 research outputs found

    ENGINEERING AN OLEOGINOUS YEAST FOR THE PRODUCTION OF BIODIESEL

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    poster abstractThere are economic and social interests in replacing the current energy dependence we have on petroleum-based oleochemicals. Yarrowia lipolytica, an oleaginous yeast, has the ability to metabolize unique carbon sources, particularly hydrocarbons and to accumulate large amounts of lipids which could be developed into a source of biodiesel. The ability of Y. lipolytica to accumulate triacylglycerols in lipid droplets and the complete sequencing of its genome make Y. lipolytica a viable organism to genetically engineer for the production of large quantities of biodiesel precursors. The purpose of this project is to genetically modify Y. lipolytica to further increase its production of triacylglycerols by knocking out genes that encode enzymes involved in the β-oxidation of fatty acids. This genetic modification will be accomplished by using homologous recombination to disrupt the genes POX3-5 and POT1. The 5’ and 3’ untranslated regions of POX3-5 and POT1 were amplified by polymerase chain reaction and cloned to allow a drug resistance gene to be introduced between them. Following cloning, these genes will be knocked out from the Y. lipolytica genome using drug resistance as a marker. The disruption of these genes is expected to increase the accumulation of triacylglycerols in Y. lipolytica lipid droplets versus the wild-type. Progress towards the goals of this project will be reported

    On Properties of Vacuum Axial Symmetric Spacetime of Gravitomagnetic Monopole in Cylindrical Coordinates

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    We investigate general relativistic effects associated with the gravitomagnetic monopole moment of gravitational source through the analysis of the motion of test particles and electromagnetic fields distribution in the spacetime around nonrotating cylindrical NUT source. We consider the circular motion of test particles in NUT spacetime, their characteristics and the dependence of effective potential on the radial coordinate for the different values of NUT parameter and orbital momentum of test particles. It is shown that the bounds of stability for circular orbits are displaced toward the event horizon with the growth of monopole moment of the NUT object. In addition, we obtain exact analytical solutions of Maxwell equations for magnetized and charged cylindrical NUT stars.Comment: 16 pages, 3 figures, 1 tabl

    Environmental Baseline Monitoring Project. Phase II, final report

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    This report is submitted in compliance with the conditions set out in the grant awarded to the British Geological Survey (BGS), for the period April 2016 – March 2017, to support the jointly-funded project "Science-based environmental baseline monitoring". It presents the results of monitoring and/or measurement and preliminary interpretation of these data to characterise the baseline environmental conditions in the Vale of Pickering, North Yorkshire and for air quality, the Fylde in Lancashire ahead of any shale gas development. The two areas where the monitoring is taking place have seen, during the project, planning applications approved for the exploration for shale gas and hydraulic fracturing. It is widely recognised that there is a need for good environmental baseline data and establishment of effective monitoring protocols ahead of any shale gas/oil development. This monitoring will enable future changes that may occur as a result of industrial activity to be identified and differentiated from other natural and man-made changes that are influencing the baseline. Continued monitoring will then enable any deviations from the baseline, should they occur, to be identified and investigated independently to determine the possible causes, sources and significance to the environment and public health. The absence of such data in the United States has undermined public confidence, led to major controversy and inability to identify and effectively deal with impact/contamination where it has occurred. A key aim of this work is to avoid a similar situation and the independent monitoring being carried out as part of this project provides an opportunity to develop robust environmental baseline for the two study areas and monitoring procedures, and share experience that is applicable to the wider UK situation. This work is internationally unique and comprises an inter-disciplinary researcher-led programme that is developing, testing and implementing monitoring methodologies to enable future environmental changes to be detected at a local scale (individual site) as well as across a wider area, e.g. ‘shale gas play’ where cumulative impacts may be significant. The monitoring includes: water quality (groundwater and surface water), seismicity, ground motion, soil gas, atmospheric composition (greenhouse gases and air quality) and radon in air. Recent scientific and other commissioned studies have highlighted that credible and transparent monitoring is key to gaining public acceptance and providing the evidence base to demonstrate the industry’s impact on the environment and importantly on public health. As a result, BGS and its partners initiated in early 2015, a co-ordinated programme of environmental monitoring in Lancashire that was then extended to the Vale of Pickering in North Yorkshire after the Secretary of State for Energy and Climate Change (BEIS) awarded a grant to the British Geological Survey (BGS). The current duration of the grant award is to 31st March 2018. It has so far enabled baseline environmental monitoring for a period of more than 12 months. With hydraulic fracturing of shale gas likely to take place during late 2017/early 2018, the current funding will allow the environmental monitoring to continue during the transition from baseline to monitoring during shale gas operations. This report presents the monitoring results to April 2017 and a preliminary interpretation. A full interpretation is not presented in this report as monitoring is continuing and it is expected that there will be at least six months of additional baseline data before hydraulic fracturing takes place. This represents up to 50% more data for some components of the montoring, and when included in the analysis will significantly improve the characterisation and interpretation of the baseline. In addition to this report, the BGS web site contains further information on the project, near real-time data for some components of the monitoring and links to other projects outputs, e.g. reports and videos (www.bgs.ac.uk/research/groundwater/shaleGas/monitoring/home.html)

    Systematic Study of Electron Localization in an Amorphous Semiconductor

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    We investigate the electronic structure of gap and band tail states in amorphous silicon. Starting with two 216-atom models of amorphous silicon with defect concentration close to the experiments, we systematically study the dependence of electron localization on basis set, density functional and spin polarization using the first principles density functional code Siesta. We briefly compare three different schemes for characterizing localization: information entropy, inverse participation ratio and spatial variance. Our results show that to accurately describe defect structures within self consistent density functional theory, a rich basis set is necessary. Our study revealed that the localization of the wave function associated with the defect states decreases with larger basis sets and there is some enhancement of localization from GGA relative to LDA. Spin localization results obtained via LSDA calculations, are in reasonable agreement with experiment and with previous LSDA calculations on a-Si:H models.Comment: 16 pages, 11 Postscript figures, To appear in Phys. Rev.

    The 2dF QSO Redshift Survey - V. The 10k catalogue

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    We present a catalogue comprising over 10 000 QSOs covering an effective area of 289.6 deg2, based on spectroscopic observations with the 2-degree Field (2dF) instrument at the Anglo-Australian Telescope. This catalogue forms the first release of the 2dF QSO Redshift Survey. QSO candidates with 18.2

    Recommendations for environmental baseline monitoring in areas of shale gas development

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    Environmental monitoring plays a key role in risk assessment and management of industrial operations where there is the potential for the release of contaminants to the environment (i.e. air and water) or for structural damage (i.e. seismicity). The shale-gas industry is one such industry. It is also new to the UK and so specific environmental regulation and other controls have been introduced only recently. Associated with this is a need to carry out monitoring to demonstrate that the management measures to minimise the risk to the environment are being effective. While much of the monitoring required is common to other industries and potentially polluting activities, there are a number of requirements specific to shale gas and to what is a new and undeveloped industry. This report presents recommendations for environmental monitoring associated with shale-gas activities and in particular the monitoring required to inform risk assessment and establish the pre-existing environmental conditions at a site and surrounding area. This baseline monitoring is essential to provide robust data and criteria for detecting any future adverse environmental changes caused by the shale-gas operations. Monitoring is therefore required throughout the lifecycle of a shale gas operation. During this lifecycle, the objectives of the monitoring will change, from baseline characterisation to operational and post-operational monitoring. Monitoring requirements will also change. This report focusses on good practice in baseline monitoring and places it in the context of the longer-term environmental monitoring programme, recognising the need to transition from the baseline condition and to establish criteria for detecting any changes within the regulatory framework. The core suite of environmental monitoring activities currently required to support regulatory compliance, i.e. meet environmental and other permit conditions, encompasses monitoring of seismicity, water quality (groundwater and surface water) and air quality. Recommendations for each of these are included in this report. Additionally, recommendations for a number of other types of environmental monitoring are included – radon in air, soil gas and ground motion (subsidence/uplift). These are not associated directly with regulatory compliance but can provide information to support interpretation of statutory monitoring results. They are also considered important for public reassurance. Health impacts arising from radon and damage caused by ground motion are both issues of public concern in relation to shale gas

    In the eye of the beholder:promoting learner-centric design to develop mobile games for learning

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    Out of the project EMuRgency a game-based learning environment evolved, which trains school children in providing reanimation and cardiopulmonary resuscitation (CPR). The application gets players to act as if they were in a real case of emergency. This paper reports on a formal usability study conducted with two different groups of learners, regular learners and learners with special educational needs (SEN). With the study we compared the two groups of learners with regard to game usability and effectiveness of the intervention. Our intention was to better understand the different needs and requirements to learning materials that game designer need to take into consideration in order to make the learning experience successful for both groups. A total of 89 children played the game simulation. Results showed differences in perception and effectiveness of individual mechanisms for the two groups with regard to usability or switching between tasks and mobile device.This publication was partly financed by the European Regional Development Fund (ERDF), regions of the Euregio Meuse-Rhine and the participating institutions under the INTERREG IVa program (EMR.INT4-1.2.-2011-04/070, http://www.emurgency.eu)

    Preliminary assessment of the environmental baseline in the Fylde, Lancashire

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    This report presents the collated preliminary results from the British Geological Survey (BGS) led project Science-based environmental baseline monitoring associated with shale gas development in the Fylde, Lancashire. The project has been funded by a combination of BGS National Capability funding, in-kind contributions from project partners and a grant awarded by the Department of Business Energy and Investment Strategy (BEIS). It complements an on-going project, in which similar activities are being carried out, in the Vale of Pickering, North Yorkshire. Further information on the projects can be found on the BGS website: www.bgs.ac.uk. The project has initiated a wide-ranging environmental baseline monitoring programme that includes water quality (groundwater and surface water), seismicity, ground motion, atmospheric composition (greenhouse gases and air quality), soil gas and radon in air (indoors and outdoors). The motivation behind the project(s) was to establish independent monitoring in the area around the proposed shale gas hydraulic fracturing sites in the Fylde, Lancashire (Cuadrilla Resources Ltd) before any shale gas operations take place. As part of the project, instrumentation has been deployed to measure, in real-time or near real-time, a range of environmental variables (water quality, seismicity, atmospheric composition). These data are being displayed on the project’s web site (www.bgs.ac.uk/lancashire). Additional survey, sampling and monitoring has also been carried out through a co-ordinated programme of fieldwork and laboratory analysis, which has included installation of new monitoring infrastructure, to allow compilation of one of the most comprehensive environmental datasets in the UK. The monitoring programme is continuing. However, there are already some very important findings emerging from the limited datasets which should be taken into account when developing future monitoring strategy, policy and regulation. The information is not only relevant to Lancashire but will be applicable more widely in the UK and internationally. Although shale gas operations in other parts of the world are well-established, there is a paucity of good baseline data and effective guidance on monitoring. The project will also allow the experience gained, and the scientifically-robust findings to be used, to develop and establish effective environmental monitoring strategies for shale gas and similar industrial activities

    Structure, mass and stability of galactic disks

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    In this review I concentrate on three areas related to structure of disks in spiral galaxies. First I will review the work on structure, kinematics and dynamics of stellar disks. Next I will review the progress in the area of flaring of HI layers. These subjects are relevant for the presence of dark matter and lead to the conclusion that disk are in general not `maximal', have lower M/L ratios than previously suspected and are locally stable w.r.t. Toomre's Q criterion for local stability. I will end with a few words on `truncations' in stellar disks.Comment: Invited review at "Galaxies and their Masks" for Ken Freeman's 70-th birthday, Sossusvlei, Namibia, April 2010. A version with high-res. figures is available at http://www.astro.rug.nl/~vdkruit/jea3/homepage/Namibiachapter.pd
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