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Szmodis A.W.,University of California at Davis | Blanchette C.D.,University of California at Davis | Longo M.L.,University of California at Davis | Orme C.A.,Lawrence Livermore National Laboratory | Parikh A.N.,University of the Californias

The authors have studied microstructure evolution during thermally induced phase separation in a class of binary supported lipid bilayers using a quantitative application of imaging ellipsometry. The bilayers consist of binary mixtures consisting of a higher melting glycosphingolipid, galactosylceramide (GalCer), which resides primarily in the outer leaflet, and a lower melting, unsaturated phospholipid, 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC). Three different bilayer compositions of GalCer/DLPC mixtures at 35:65, 20:80, and 10:90 molar ratios were cooled at controlled rates from their high-temperature homogeneous phase to temperatures corresponding to their phase coexistence regime and imaged in real time using imaging ellipsometry. During the thermotropic course of GalCer gelation, we find that two distinct types of morphological features modulate. First, the formation and growth of chain and fractal-like defects ascribed to the net change in molecular areas during the phase transition. The formation of these defects is consistent with the expected contraction in the molecular area during the liquid crystalline to gel-phase transition. Second, the nucleation and growth of irregularly shaped gel-phase domains, which exhibit either line-tension dominated compact shape or dendritic domains with extended interfaces. Quantifying domain morphology within the fractal framework reveals a close correspondence, and the quantization of the transition width confirms previous estimates of reduced phase transition cooperativity in supported bilayers. A comparison of domain properties indicates that thermal history, bilayer composition, and cooling rate all influence microstructure details including shapes, sizes, and distributions of domains and defects: At lower cooling rates and lower GalCer fractions compact domains form and at higher GalCer fractions (or at higher cooling rates) dendritic domains are evident. This transition of domain morphology from compact shapes to dendritic shapes at higher cooling rates and higher relative fractions of GalCer suggests kinetic control of shape equilibration in these phospho- and glycolipid mixtures. © 2010 American Vacuum Society. Source

Woolf B.P.,University of Massachusetts Amherst | Lane H.C.,University of the Californias | Chaudhri V.K.,SRI International | Kolodner J.L.,Georgia Institute of Technology
AI Magazine

This article focuses on contributions that AI can make to address longterm educational goals. Challenges are described that support: (1) mentors for every learner; (2) learning 21st century skills; (3) interaction data for learning; (4) universal access to global classrooms; and (5) lifelong and lifewide learning. A vision and brief research agenda are described for each challenge along with goals that lead to development of global educational resources and the reuse and sharing of digital educational resources. Instructional systems with AI technology are described that currently support richer experiences for learners and supply researchers with new opportunities to analyze vast data sets of instructional behavior from big databases that record elements of learning, affect, motivation, and social interaction. Personalized learning is described that facilitates student and group experience, reflection, and assessment. Copyright © 2013, Association for the Advancement of Artificial Intelligence. All rights reserved. Source

Kazemzadeh A.,University of the Californias
2010 IEEE World Congress on Computational Intelligence, WCCI 2010

In this paper we describe a methodology that uses interval type-2 fuzzy logic to translate words that refer to emotions from Spanish to English. We build on previous research that aimed to map between emotional labels used in different natural language corpora. In this paper we extend our previous work by showing how a similar method can be used to translate between languages. First, we show how this methodology relates to other fuzzy logic emotion research, then we describe it, and finally show it in use and discuss its results. © 2010 IEEE. Source

Boehm B.,University of the Californias | Boehm B.,University of Southern California | Boehm B.,US National Academy of Engineering
IEEE Software

Software evaluation has evolved and taken several forms, providing rapid change handling and high assurance. The single-step-to-full-capability process exemplified by the traditional waterfall or sequential V-model is appropriate if the product's requirements are prespecifiable and have a low probability of significant change, and if there's no value or chance to deliver a partial product capability. The evolutionary sequential process develops an initial operational capability and upgrades it on the basis of operational experience. Development team stabilized for on-time, high-assurance delivery of the current increment and employing a concurrent verification and validation team to perform continuous defect detection to enable even higher-assurance levels. Source

Bostic R.W.,University of the Californias | Rudd E.C.,Office of Policy Development and Research | Sternthal M.J.,Deputy director of federal affairs
Health Affairs

The link between federal housing policy and public health has been understood since the nineteenth century, when housing activists first sought to abolish slums and create healthful environments. This article describes how the Obama administration-building on these efforts and those that followed, including the Great Society programs of President Lyndon Johnson-has adopted a cross-sector approach that takes health considerations into account when formulating housing and community development policy. The federal Department of Housing and Urban Development fully embraces this "health in all policies" approach. Nonetheless, the administration's strategy faces challenges, including fiscal and political ones. Some of these challenges may be overcome by conducting quality research on how housing and community development policies affect health outcomes, and by developing a federal budget strategy that takes into account how investments in one sector contribute to cost savings in another. ©2012 Project HOPE- The People-to-People Health Foundation, Inc. Source

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