5,592 research outputs found

    SCOS2: ESA's new generation of mission control systems

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    The paper describes the next generation Spacecraft Control System infrastructure (SCOSII) which is being developed at the Operations Centre (ESOC) of the European Space Agency (ESA). The objectives of the new system and selected areas of the proposed hardware and software approach are described

    Evidence for ACTN3 as a genetic modifier of Duchenne muscular dystrophy

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    Duchenne muscular dystrophy (DMD) is characterized by muscle degeneration and progressive weakness. There is considerable inter-patient variability in disease onset and progression, which can confound the results of clinical trials. Here we show that a common null polymorphism (R577X) in ACTN3 results in significantly reduced muscle strength and a longer 10\u2009m walk test time in young, ambulant patients with DMD; both of which are primary outcome measures in clinical trials. We have developed a double knockout mouse model, which also shows reduced muscle strength, but is protected from stretch-induced eccentric damage with age. This suggests that \u3b1-actinin-3 deficiency reduces muscle performance at baseline, but ameliorates the progression of dystrophic pathology. Mechanistically, we show that \u3b1-actinin-3 deficiency triggers an increase in oxidative muscle metabolism through activation of calcineurin, which likely confers the protective effect. Our studies suggest that ACTN3 R577X genotype is a modifier of clinical phenotype in DMD patients

    SCOS 2: ESA's new generation of mission control system

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    New mission-control infrastructure is currently being developed by ESOC, which will constitute the second generation of the Spacecraft Control Operations system (SCOS 2). The financial, functional and strategic requirements lying behind the new development are explained. The SCOS 2 approach is described. The technological implications of these approaches is described: in particular it is explained how this leads to the use of object oriented techniques to provide the required 'building block' approach. The paper summarizes the way in which the financial, functional and strategic requirements have been met through this combination of solutions. Finally, the paper outlines the development process to date, noting how risk reduction was achieved in the approach to new technologies and summarizes the current status future plans

    Lunar International Science Coordination/Calibration Targets

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    A new era of international lunar exploration has begun and will expand over the next four years with data acquired from at least four sophisticated remote sensing missions: KAGUYA (SELENE) [Japan], Chang'E [China], Chandrayaan-l [India], and LRO [United States]. It is recognized that this combined activity at the Moon with modern sophisticated sensors wi II provide unprecedented new information about the Moon and will dramatically improve our understanding of Earth's nearest neighbor. It is anticipated that the blooming of scientific exploration of the Moon by nations involved in space activities will seed and foster peaceful international coordination and cooperation that will benefit all. Summarized here are eight Lunar International Science Coordination/Calibration Targets (L-ISCT) that are intended to a) allow cross-calibration of diverse multi-national instruments and b) provide a focus for training young scientists about a range of lunar science issues. The targets, discussed at several scientific forums, were selected for coordinated science and instrument calibration of orbital data. All instrument teams are encouraged to participate in a coordinated activity of early-release data that will improve calibration and validation of data across independent and diverse instruments

    The Effect of Flipped Instruction on Special Education Preservice Teachers\u27 Perceptions

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    This study analyzes the flipped instruction model used in three special education educator preparation courses to examine which components preservice teachers perceived most contributed to their content knowledge, motivation, and engagement (n=50). Weekly pre-class asynchronous assignments included the use of educational technology tools such as an interactive e-textbook site, Perusall, and online academic activities such as Khan Academy to strengthen their content knowledge. This allowed more time for a student-centered approach during synchronous instruction to incorporate tools such as Nearpod, Pear Deck, Flipgrid and digital badges to strength-en their motivation and engagement. Data were collected through a post-course survey; results indicate that preservice teachers perceived this model was motivating, engaging, and contributed significantly to their content knowledge. They also identified hands-on activities during class as a significant component of their learning. This article discusses the project, limitations, and implications for future flipped instruction research in special education educator preparation programs

    The Effect of Flipped Instruction on Special Education Preservice Teachers\u27 Perceptions

    Get PDF
    This study analyzes the flipped instruction model used in three special education educator preparation courses to examine which components preservice teachers perceived most contributed to their content knowledge, motivation, and engagement (n=50). Weekly pre-class asynchronous assignments included the use of educational technology tools such as an interactive e-textbook site, Perusall, and online academic activities such as Khan Academy to strengthen their content knowledge. This allowed more time for a student-centered approach during synchronous instruction to incorporate tools such as Nearpod, Pear Deck, Flipgrid and digital badges to strength-en their motivation and engagement. Data were collected through a post-course survey; results indicate that preservice teachers perceived this model was motivating, engaging, and contributed significantly to their content knowledge. They also identified hands-on activities during class as a significant component of their learning. This article discusses the project, limitations, and implications for future flipped instruction research in special education educator preparation programs

    Trauma as counter-revolutionary colonisation: narratives from (post)revolutionary Egypt

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    We argue that multiple levels of trauma were present in Egypt before, during and after the 2011 revolution. Individual, social and political trauma constitute a triangle of traumatisation which was strategically employed by the Egyptian counter-revolutionary forces – primarily the army and the leadership of the Muslim Brotherhood – to maintain their political and economic power over and above the social, economic and political interests of others. Through the destruction of physical bodies, the fragmentation and polarisation of social relations and the violent closure of the newly emerged political public sphere, these actors actively repressed the potential for creative and revolutionary transformation. To better understand this multi-layered notion of trauma, we turn to Habermas’ ‘colonisation of the lifeworld’ thesis which offers a critical lens through which to examine the wider political and economic structures and context in which trauma occurred as well as its effects on the personal, social and political realms. In doing so, we develop a novel conception of trauma that acknowledges individual, social and political dimensions. We apply this conceptual framing to empirical narratives of trauma in Egypt’s pre- and post-revolutionary phases, thus both developing a non-Western application of Habermas’ framework and revealing ethnographic accounts of the revolution by activists in Cairo

    Inelastic transport theory from first-principles: methodology and applications for nanoscale devices

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    We describe a first-principles method for calculating electronic structure, vibrational modes and frequencies, electron-phonon couplings, and inelastic electron transport properties of an atomic-scale device bridging two metallic contacts under nonequilibrium conditions. The method extends the density-functional codes SIESTA and TranSIESTA that use atomic basis sets. The inelastic conductance characteristics are calculated using the nonequilibrium Green's function formalism, and the electron-phonon interaction is addressed with perturbation theory up to the level of the self-consistent Born approximation. While these calculations often are computationally demanding, we show how they can be approximated by a simple and efficient lowest order expansion. Our method also addresses effects of energy dissipation and local heating of the junction via detailed calculations of the power flow. We demonstrate the developed procedures by considering inelastic transport through atomic gold wires of various lengths, thereby extending the results presented in [Frederiksen et al., Phys. Rev. Lett. 93, 256601 (2004)]. To illustrate that the method applies more generally to molecular devices, we also calculate the inelastic current through different hydrocarbon molecules between gold electrodes. Both for the wires and the molecules our theory is in quantitative agreement with experiments, and characterizes the system-specific mode selectivity and local heating.Comment: 24 pages, 17 figure
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