24,528 research outputs found
Wave packet dynamics of potassium dimers attached to helium nanodroplets
The dynamics of vibrational wave packets excited in K dimers attached to
superfluid helium nanodroplets is investigated by means of femtosecond
pump-probe spectroscopy. The employed resonant three-photon-ionization scheme
is studied in a wide wavelength range and different pathways leading to
K-formation are identified. While the wave packet dynamics of the
electronic ground state is not influenced by the helium environment,
perturbations of the electronically excited states are observed. The latter
reveal a strong time dependence on the timescale 3-8 ps which directly reflects
the dynamics of desorption of K off the helium droplets
Design definition study of a lift/cruise fan technology V/STOL airplane: Summary
A two-engine three-fan V/STOL airplane was designed to fulfill naval operational requirements. A multimission airplane was developed from study of specific point designs. Based on the multimission concept, airplanes were designed to demonstrate and develop the technology and operational procedures for this class of aircraft. Use of interconnected variable pitch fans led to a good balance between high thrust with responsive control and efficient thrust at cruise speeds. The airplanes and their characteristics are presented
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Alterations in T1 of normal and reperfused infarcted myocardium after Gd-BOPTA versus GD-DTPA on inversion recovery EPI.
This study tested whether Gd-BOPTA/Dimeg or Gd-DTPA exerts greater relaxation enhancement for blood and reperfused infarcted myocardium. Relaxivity of Gd-BOPTA is increased by weak binding to serum albumin. Thirty-six rats were subjected to reperfused infarction before contrast (doses = 0.05, 0.1, and 0.2 mmol/kg). delta R1 was repeatedly measured over 30 min. Gd-BOPTA caused greater delta R1 for blood and myocardium than did Gd-DTPA; clearance of both agents from normal- and infarcted myocardium was similar to blood clearance; plots of delta R1 myocardium/delta R1 blood showed equilibrium phase contrast distribution. Fractional contrast agent distribution volumes were approximately 0.24 for both agents in normal myocardium, 0.98 and 1.6 for Gd-DTPA and Gd-BOPTA, respectively, in reperfused infarction. The high value for Gd-BOPTPA was ascribed to greater relaxivity in infarction versus blood. It was concluded that Gd-BOPTA/Dimeg causes a greater delta R1 than Gd-DTPA in regions which contain serum albumin
A Fisher-eye lens on social work reform
Summary
Mark Fisherâs Capitalist Realism, published in 2009, has been recognised as one of the most important contributions chronicling the rise, application and consequences of neoliberalism. However, Fisherâs ideas have until now only garnered passing mention in the study of neoliberalism in children and families social work in England, despite there being extensive research, argument and publication on the subject more broadly. This article attempts to rectify this gap and apply Fisherâs theory to the recent reforms in children and families social work in England.
Findings
The article applies Fisherâs commentary on the co-option of language, invoking crisis, bureaucracy and proposing change to implement no change, to the reforms in children and families social work that began with the implementation of Reclaiming Social Work in 2008. Since that time, the original architects of Reclaiming Social Work have gained significant positions of power and influence and been instrumental in introducing neoliberal reforms throughout children and families social work in England.
Applications
Through applying the approach and concepts of Mark Fisher, this article concludes that it is possible to determine that the current reforms are, at their core, neoliberal in nature and driven by an ideological imperative to transform children and families social work in England into a neoliberal edifice, with less public sector and state input and oversight and an increase in the influence of ânot-for-profitsâ, charities and international for-profit consultancies
The effects of room design on computer-supported collaborative learning in a multi-touch classroom.
While research indicates that technology can be useful for supporting learning and collaboration, there is still relatively little uptake or widespread implementation of these technologies in classrooms. In this paper, we explore one aspect of the development of a multi-touch classroom, looking at two different designs of the classroom environment to explore how classroom layout may influence group interaction and learning. Three classes of students working in groups of four were taught in the traditional forward-facing room condition, while three classes worked in a centered room condition. Our results indicate that while the outcomes on tasks were similar across conditions, groups engaged in more talk (but not more off-task talk) in a centered room layout, than in a traditional forward-facing room. These results suggest that the use of technology in the classroom may be influenced by the location of the technology, both in terms of the learning outcomes and the interaction behaviors of students. The findings highlight the importance of considering the learning environment when designing technology to support learning, and ensuring that integration of technology into formal learning environments is done with attention to how the technology may disrupt, or contribute to, the classroom interaction practices
Tool support for security-oriented virtual research collaborations
Collaboration is at the heart of e-Science and e-Research
more generally. Successful collaborations must address both
the needs of the end user researchers and the providers
that make resources available. Usability and security are
two fundamental requirements that are demanded by many
collaborations and both concerns must be considered from
both the researcher and resource provider perspective. In
this paper we outline tools and methods developed at the
National e-Science Centre (NeSC) that provide users with
seamless, secure access to distributed resources through
security-oriented research environments, whilst also allowing resource providers to define and enforce their own local access and usage policies through intuitive user interfaces. We describe these tools and illustrate their application in the ESRC-funded Data Management through e-Social Science (DAMES) and the JISC-funded SeeGEO projects
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