403 research outputs found

    In Vacuum High Accuracy Mechanical Positioning System of Nano Resolution Beam Position Monitor at the Interaction Point of ATF2

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    TUOCB203 - ISBN 978-3-95450-122-9International audienceATF2 is a low energy (1.3GeV) prototype of the final focus system for ILC and CLIC linear collider projects. A major goal of ATF2 is to demonstrate the ability to stabilise the beam position at the interaction point, where the beam can be focused down to about 35 nm. For this purpose, a set of new Beam Position Monitors (BPM) has been designed, with an expected resolution of about 2 nm. These BPMs must be very well aligned with respect to the beam, at the few micron level, to fully exploit their fine resolution. In this paper, the mechanical positioning system which has been developed to enable such a precise alignment is presented. It is based on a set of eight piezo actuators with nanometer range displacement resolution, mounted in a new specially made vacuum chamber. Due to the expected resolution of the piezo actuators, this system also brings a new functionality, the possibility to calibrate the BPMs by mechanically scanning the beam

    Genetic analysis of grain protein deviation in wheat

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    Genetic analysis of grain protein deviation in wheat

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    Relatório de estágio do mestrado em Ensino da Educação Física nos Ensinos Básico e Secundário, apresentado à Faculdade de Ciências do Desporto e Educação Física da Universidade de CoimbraO Estágio Pedagógico operacionalizado na Escola Secundária de Anadia representou a possibilidade de aplicar em contexto real os conhecimentos e saberes científicos adquiridos ao longo do curso, aliados à experiência profissional já adquirida. Ao longo deste percurso assumiu particular importância a reflexão constante sobre a prática, aliada à investigação e mobilização de saberes pertinentes. É esta dinâmica que permite ao professor ser produtor da sua profissão, ser um profissional reflexivo e crítico, pois o ato de ensinar representa uma atividade transformadora da sociedade. Os professores devem questionar diariamente o que ensinam, a forma como o fazem e os objetivos que perseguem. A cultura de profissionalidade docente assenta no conhecimento pedagógico de e para a mestria. Uma das principais conclusões deste processo de formação evidencia a necessidade de ensinar e promover a aprendizagem para todos os alunos. Até os menos aptos no domínio motor podem aceder a níveis elevados de aprendizagem, desde que beneficiem de oportunidades e condições educativas apropriadas. Esta é uma preocupação que deve assistir a todos os professores, pois trata-se acima de tudo, de uma questão de responsabilidade educativa social. Apenas com professores que acreditem na importância da qualidade do ensino se pode credibilizar a Educação Física. Assiste-se a um momento de particular incerteza, sobretudo nas orientações emanadas da administração central, evidenciadas, por exemplo, na exclusão da nota de Educação Física no apuramento da média final do Ensino Secundário. Esta medida constituiu uma clara desvalorização da disciplina, com reflexos negativos na participação e empenho motor dos alunos. Cabe-nos a nós, futuros profissionais, guiados por valores éticos e morais, devolver o reconhecimento da importância inequívoca da disciplina de Educação Física, com estatuto formal igual às demais. The Teaching Practice that took place in the Secondary School of Anadia provided the possibility to apply in real context the scientific knowledge and skills acquired while taking the degree, combined with professional experience already acquired. Throughout this path, it became particularly important the constant reflection on the practice, along with the research and the use of relevant knowledge. This dynamics allows the teacher to be a producer of his career, to be a reflective and critical professional, as teaching is an activity that enables society to change. Teachers should question what they teach, how they teach and their teaching goals. The professional teaching culture is based on knowledge and teaching to mastery. One of the main conclusions of this practice process highlights the need to teach and to promote learning for all students. Even the least able at the motor domain, can have access to higher levels of learning, if they are given the educational opportunities and the appropriate conditions. This is a concern all teachers should have in mind, since that is a question of educational and social responsibility. Only the teachers who believe in the importance of the quality of education can make Physical Education more credible. We are witnessing a moment of particular uncertainty, especially in the guidelines issued by the government, seen mainly when the Physical Education marks are not taken into account to calculate the final average of Secondary School Education. This measure was a clear devaluation of this school subject, with negative effects on students’ participation and effort. It is up to us, as future professionals guided by ethical and moral values, to gain back the recognition of the clear relevance of Physical Education – a subject as important as all the others

    Preliminary data on boulders at station 6, Apollo 17 landing site

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    A cluster of boulders at Station 6 (Apollo 17 landing site) consists of breccias derived from the North Massif. Three preliminary lithologic units were established, on the basis of photogeologic interpretations; all lithologies identified photogeologically were sampled. Breccia clasts and matrices studied petrographically and chemically fall into two groups by modal mineralogy: (1) low-K Fra Mauro or high basalt composition, consisting of 50-60% modal feldspar, approximately 45% orthopyroxene and 1-7% Fe-Ti oxide; (2) clasts consisting of highland basalt composition, consisting of 70% feldspar, 30% orthopyroxene and olivine and a trace of Fe-Ti oxide

    Impactor flux and cratering on Ceres and Vesta: Implications for the early Solar System

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    We study the impactor flux and cratering on Ceres and Vesta caused by the collisional and dynamical evolution of the asteroid Main Belt. We develop a statistical code based on a well-tested model for the simultaneous evolution of the Main Belt and NEA size distributions. This code includes catastrophic collisions and noncollisional removal processes such as the Yarkovsky effect and the orbital resonances. The model assumes that the dynamical depletion of the early Main Belt was very strong, and owing to that, most Main Belt comminution occurred when its dynamical structure was similar to the present one. Our results indicate that the number of D > 1 km Main Belt asteroids striking Ceres and Vesta over the Solar System history are approximately 4 600 and 1 100 respectively. The largest Main Belt asteroids expected to have impacted Ceres and Vesta had diameters of 71.7 km and 21.1 km. The number of D > 0.1 km craters on Ceres is \sim 3.4 \times 10^8 and 6.2 \times 10^7 on Vesta. The number of craters with D > 100 km are 47 on Ceres and 8 on Vesta. Our study indicates that the D = 460 km crater observed on Vesta had to be formed by the impact of a D \sim 66.2 km projectile, which has a probability of occurr \sim 30% over the Solar System history. If significant discrepancies between our results about the cratering on Ceres and Vesta and data obtained from the Dawn Mission were found, they should be linked to a higher degree of collisional evolution during the early Main Belt and/or the existence of the late heavy bombardment. An increase in the collisional activity in the early phase may be provided for an initial configuration of the giant planets consistent with, for example, the Nice model. From this, the Dawn Mission would be able to give us clues about the initial configuration of the early Solar System and its subsequent dynamical evolution.Comment: Accepted for publication in Astronomy and Astrophysic

    First step towards the new SPIRAL2 project control system

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    International audienceThe Spiral2 project at Ganil aims to produce rare ion beams using a Uranium carbide target fission process. The accelerator consists of a RFQ followed by a superconducting cavity linac and is designed to provide high intensity primary beams (deuterons, protons or heavy ions). The accelerator should be commissioned by the end of 2011; then, the first tests aiming to produce exotic beams are planned one year later. The control system will result of the collaboration between several institutes among which the Saclay Dapnia division yet having a good experience and knowledge with Epics. So and also because of its widely used functionalities, Epics has been chosen as the basic framework for the accelerator control and people from the other laboratories belonging to the collaboration are progressively acquiring a first experience with Epics. The paper first explains the organisation of the collaboration then it describes the basic hardware and software choices for the project. Some preliminary implementations are therefore given. As the project is still in its beginning phase, the paper ends by listing some interrogations not yet solved for the control system definition and opened for discussion

    Status of Diamond Detector Development for Beam Halo Investigation at ATF2

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    Work supported by Chinese Scholarship Council - THPME092, ISBN 978-3-95450-132-8International audienceWe are developing a diamond detector for beam halo and Compton spectrum diagnostics after the interaction point (IP) of ATF2, a low energy (1.3 GeV) prototype of the final focus system for ILC and CLIC linear collider projects. Tests of a 500 μm thick sCVD diamond detector with a dimension of 4.5 mm×4.5 mm have been carried out with radioactive sources and with electron beam from PHIL low energy (<10 MeV) photo-injector at LAL. The tests at PHIL were done with different beam intensities in air, just after the exit window at the end of the beam line, to test the response of the diamond detector and the readout electronics. We have successfully detected signals from single electrons, using a 40 dB amplifier, and from an electron beam of 108 electrons, using a 24 dB attenuator. A diamond sensor with 4 strips has been designed and fabricated for installation in the vacuum chambers of ATF2 and PHIL, with the aim to scan both the beam halo (with 2 strips of 1.5 mm×4 mm) and the beam core (with 2 strips of 0.1 mm×4 mm) transverse distributions

    Status of the light ion source developments at CEA/Saclay

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    ACC NIMInternational audienceSILHI (High Intensity Light Ion Source) is an ECR ion source producing high intensity proton ordeuteron beams at 95 keV. It is now installed in the IPHI site building, on the CEA/Saclay center. IPHI is a frontend demonstrator of high power accelerator. The source regularly delivers more than 130 mA protons in CWmode and already produced more than 170 mA deuterons in pulsed mode at nominal energy. The last beamcharacterisations, including emittance measurements, space charge compensation analysis and diagnosticimprovements, will be reported. Taking into account the SILHI experience, new developments are in progress tobuild and test a 5 mA deuteron source working in CW mode. This new source will also operate at 2.45 GHz andpermanent magnets will provide the magnetic configuration. This source, of which the design will be discussed,will have to fit in with the SPIRAL 2 accelerator developed at GANIL to produce Radioactive Ion Beams. TheH- test stand status is briefly presented here and detailed in companion papers.This work is partly supported by the European Commission under contract n°: HPRI-CT-2001-50021

    Remnants of Cardinal Symptoms of Parkinson's Disease, Not Dyskinesia, Are Problematic for Dyskinetic Patients Performing Activities of Daily Living

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    Introduction: The impact of levodopa-induced dyskinesia (LID) on the daily lives of patients with Parkinson's disease (PD) remains to be determined. Furthermore, evidence suggests that cardinal motor symptoms of PD may coexist with LID, but their impact on activities of daily living (ADL) relative to LID is not known. This cross-sectional study aimed at determining the effect of LID and cardinal motor symptoms of PD on ADL in patients who were experiencing peak-dose choreic-type LID.Method: One hundred and twenty-one patients diagnosed with PD known to experience choreic-type LID were recruited for the study. Patients were asked to perform a set of ADL. Levels of LID, tremor, bradykinesia, and freezing of gait (FoG) were measured using 17 inertial sensors design to capture full body movements, while rigidity, and postural instability were assessed using clinical evaluations. Cognition was also assessed using the mini-mental state examination. Success criteria were set for each ADL using the time needed to perform the task and errors measured in 69 age-gender-matched healthy controls. Binary logistic regressions were used to identify symptoms influencing success or failure for each activity. Receiver operating characteristic curves were computed on each significant symptom, and Youden indexes were calculated to determine the critical level of symptomatology at which the performance significantly changed.Results: Results show that 97.7% of patients who presented with LID during the experiment also presented with at least one cardinal motor symptom. On average, patients took more time and did more errors during ADL. Multivariate analyses revealed that for the great majority of ADL, LID were not associated with worsening of performance; however, postural instability, tremor, rigidity, and cognitive decline significantly decreased the odds of success.Conclusions: Residual symptoms of PD, such as tremor, rigidity, and postural instability still present at peak-dose were more problematic than LID in the performance of ADL for patients experiencing slight-to-moderate LID. We also found that cognitive decline was associated with decreased performance in certain tasks. Therefore, a strategy using lower doses of medication to manage LID may be counterproductive since it would not address most of these symptoms already present in patients
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