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Key Ideas (key + idea)
Selected AbstractsHydrated metal ions in the gas phaseMASS SPECTROMETRY REVIEWS, Issue 4 2007Martin K. Beyer Abstract Studying metal ion solvation, especially hydration, in the gas phase has developed into a field that is dominated by a tight interaction between experiment and theory. Since the studied species carry charge, mass spectrometry is an indispensable tool in all experiments. Whereas gas-phase coordination chemistry and reactions of bare metal ions are reasonably well understood, systems containing a larger number of solvent molecules are still difficult to understand. This review focuses on the rich chemistry of hydrated metal ions in the gas phase, covering coordination chemistry, charge separation in multiply charged systems, as well as intracluster and ion-molecule reactions. Key ideas of metal ion solvation in the gas phase are illustrated with rare-gas solvated metal ions. © 2007 Wiley Periodicals, Inc., Mass Spectrom. Rev. [source] Lazy Solid Texture SynthesisCOMPUTER GRAPHICS FORUM, Issue 4 2008Yue Dong Abstract Existing solid texture synthesis algorithms generate a full volume of color content from a set of 2D example images. We introduce a new algorithm with the unique ability to restrict synthesis to a subset of the voxels, while enforcing spatial determinism. This is especially useful when texturing objects, since only a thick layer around the surface needs to be synthesized. A major difficulty lies in reducing the dependency chain of neighborhood matching, so that each voxel only depends on a small number of other voxels. Our key idea is to synthesize a volume from a set of pre-computed 3D candidates, each being a triple of interleaved 2D neighborhoods. We present an efficient algorithm to carefully select in a pre-process only those candidates forming consistent triples. This significantly reduces the search space during subsequent synthesis. The result is a new parallel, spatially deterministic solid texture synthesis algorithm which runs efficiently on the GPU. Our approach generates high resolution solid textures on surfaces within seconds. Memory usage and synthesis time only depend on the output textured surface area. The GPU implementation of our method rapidly synthesizes new textures for the surfaces appearing when interactively breaking or cutting objects. [source] An Adaptive Sampling Scheme for Out-of-Core SimplificationCOMPUTER GRAPHICS FORUM, Issue 2 2002Guangzheng Fei Current out-of-core simplification algorithms can efficiently simplify large models that are too complex to be loaded in to the main memory at one time. However, these algorithms do not preserve surface details well since adaptive sampling, a typical strategy for detail preservation, remains to be an open issue for out-of-core simplification. In this paper, we present an adaptive sampling scheme, called the balanced retriangulation (BR), for out-of-core simplification. A key idea behind BR is that we can use Garland's quadric error matrix to analyze the global distribution of surface details. Based on this analysis, a local retriangulation achieves adaptive sampling by restoring detailed areas with cell split operations while further simplifying smooth areas with edge collapse operations. For a given triangle budget, BR preserves surface details significantly better than uniform sampling algorithms such as uniform clustering. Like uniform clustering, our algorithm has linear running time and small memory requirement. [source] Tuning of electron transport through molecular bridge systems: A study of shot noiseINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 1 2008Santanu K. Maiti Abstract We study electron transport characteristics through a single phenalenyl molecule attached with two nonsuperconducting electrodes by the use of Green's function technique. Parametric calculations are given based on the tight-binding model to characterize the electron transport through such molecular bridge system. It is observed that the electron transport properties are significantly influenced by (a) the interference effect and (b) the molecule-to-electrodes coupling strength. In this context we also describe the noise power of the current fluctuations that provides an important information about the electron correlation, which is obtained by calculating the Fano factor (F). The knowledge of this current fluctuations gives a key idea for fabrication of efficient molecular devices. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source] PARTIALLY LINEAR MODEL SELECTION BY THE BOOTSTRAPAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 2 2009Samuel Müller Summary We propose a new approach to the selection of partially linear models based on the conditional expected prediction square loss function, which is estimated using the bootstrap. Because of the different speeds of convergence of the linear and the nonlinear parts, a key idea is to select each part separately. In the first step, we select the nonlinear components using an ,m -out-of- n' residual bootstrap that ensures good properties for the nonparametric bootstrap estimator. The second step selects the linear components from the remaining explanatory variables, and the non-zero parameters are selected based on a two-level residual bootstrap. We show that the model selection procedure is consistent under some conditions, and our simulations suggest that it selects the true model most often than the other selection procedures considered. [source] Intellectuals, Tertiary Education and Questions of DifferenceEDUCATIONAL PHILOSOPHY AND THEORY, Issue 5 2007Peter Roberts Abstract In contemplating the roles and responsibilities of intellectuals in the 21st century, the notion of ,difference' is significant in at least two senses. First, work on the politics of difference allows us to consider the question ,For whom does the intellectual speak?' in a fresh light. Second, we can ask: ,To what extent, and in what ways, might our activities as intellectuals make a difference?' Thinkers such as Foucault, Kristeva, Lyotard, and Bauman (among many others) are helpful in addressing these questions. This paper sketches some of the key ideas of these thinkers and assesses their relevance for an understanding of intellectual life in contemporary tertiary education institutions. [source] The Vulnerability Cycle: Working With Impasses in Couple TherapyFAMILY PROCESS, Issue 3 2004Michele Scheinkman CSW In this article, we propose the vulnerability cycle as a construct for understanding and working with couples' impasses. We expand the interactional concept of couples' reciprocal patterns to include behavioral and subjective dimensions, and articulate specific processes that trigger and maintain couples' entanglements. We consider the vulnerability cycle as a nexus of integration in which "vulnerabilities" and "survival positions" are key ideas that bring together interactional, sociocultural, intrapsychic, and intergenerational levels of meaning and process. The vulnerability cycle diagram is presented as a tool for organizing information. We suggest a therapeutic approach for deconstructing couples' impasses and facilitating new patterns through deliberate modes of questioning, a freeze-frame technique, stimulation of calmness and reflection, separating present from past, and elicitation of alternative meanings, behaviors, empathy, and choice. This approach encourages the therapist and couple to work collaboratively in promoting change and resilience. [source] Genome-scale models of bacterial metabolism: reconstruction and applicationsFEMS MICROBIOLOGY REVIEWS, Issue 1 2009Maxime Durot Abstract Genome-scale metabolic models bridge the gap between genome-derived biochemical information and metabolic phenotypes in a principled manner, providing a solid interpretative framework for experimental data related to metabolic states, and enabling simple in silico experiments with whole-cell metabolism. Models have been reconstructed for almost 20 bacterial species, so far mainly through expert curation efforts integrating information from the literature with genome annotation. A wide variety of computational methods exploiting metabolic models have been developed and applied to bacteria, yielding valuable insights into bacterial metabolism and evolution, and providing a sound basis for computer-assisted design in metabolic engineering. Recent advances in computational systems biology and high-throughput experimental technologies pave the way for the systematic reconstruction of metabolic models from genomes of new species, and a corresponding expansion of the scope of their applications. In this review, we provide an introduction to the key ideas of metabolic modeling, survey the methods, and resources that enable model reconstruction and refinement, and chart applications to the investigation of global properties of metabolic systems, the interpretation of experimental results, and the re-engineering of their biochemical capabilities. [source] G.H. Mead: Theorist of the Social ActJOURNAL FOR THE THEORY OF SOCIAL BEHAVIOUR, Issue 1 2005ALEX GILLESPIE ABSTRACT: There have been many readings of Mead's work, and this paper proposes yet another: Mead, theorist of the social act. It is argued that Mead's core theory of the social act has been neglected, and that without this theory, the concept of taking the attitude of the other is inexplicable and the contemporary relevance of the concept of the significant symbol is obfuscated. The paper traces the development of the social act out of Dewey's theory of the act. According to Mead, Dewey's theory does not sufficiently account for consciousness. Grappling with this problematic leads Mead to several key ideas, which culminate in his theory of the social act. The social act and taking the attitude of the other are then illustrated by the analysis of a game of football. The interpretation presented has two novel aspects: first, symbolisation arises not simply through self taking the attitude of the other, but through the pairing of this attitude with the complementary attitude in self; second, self is able to take the attitude of the other to the extent that self has in actuality or in imagination previously been in the social position of the other. From this standpoint the key issue is how the attitude of self and other become integrated. New directions for empirical research, aimed at advancing this question are outlined. Finally, the paper shows how the social act can contribute to our contemporary concerns about the nature of the symbolic. [source] Beyond the ,digital natives' debate: Towards a more nuanced understanding of students' technology experiencesJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 5 2010S. Bennett Abstract The idea of the ,digital natives', a generation of tech-savvy young people immersed in digital technologies for which current education systems cannot cater, has gained widespread popularity on the basis of claims rather than evidence. Recent research has shown flaws in the argument that there is an identifiable generation or even a single type of highly adept technology user. For educators, the diversity revealed by these studies provides valuable insights into students' experiences of technology inside and outside formal education. While this body of work provides a preliminary understanding, it also highlights subtleties and complexities that require further investigation. It suggests, for example, that we must go beyond simple dichotomies evident in the digital natives debate to develop a more sophisticated understanding of our students' experiences of technology. Using a review of recent research findings as a starting point, this paper identifies some key issues for educational researchers, offers new ways of conceptualizing key ideas using theoretical constructs from Castells, Bourdieu and Bernstein, and makes a case for how we need to develop the debate in order to advance our understanding. [source] How well do middle school science programs measure up?JOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 6 2002Findings from Project 2061's curriculum review The purposes of this study were to examine how well middle school programs support the attainment of key scientific ideas specified in national science standards, and to identify typical strengths and weaknesses of these programs using research-based criteria. Nine widely used programs were examined by teams of teachers and specialists in research on teaching and learning. Reviewers found that whereas key ideas were generally present in the programs, they were typically buried between detailed or even unrelated ideas. Programs only rarely provided students with a sense of purpose for the units of study, took account of student beliefs that interfere with learning, engaged students with relevant phenomena to make abstract scientific ideas plausible, modeled the use of scientific knowledge so that students could apply what they learned in everyday situations, or scaffolded student efforts to make meaning of key phenomena and ideas presented in the programs. New middle school science programs that reflect findings from learning research are needed to support teachers better in helping students learn key ideas in science. The criteria and findings from this study on the inadequacies in existing programs could serve as guidelines in new curriculum development. © 2002 Wiley Periodicals, Inc. J Res Sci Teach 39: 522,549, 2002 [source] Milestones in ecological thought , A canon for plant ecologyJOURNAL OF VEGETATION SCIENCE, Issue 2 2005Paul A. Keddy Abstract. Scientific progress in plant ecology is at risk of being obscured by increasing ignorance of major works in the field. The driving force seems to be the twin seductions of novelty and crowd psychology. I illustrate this tendency with three examples from plant community ecology that span the past thirty years of ecological research. I offer, as one solution, the concept of a canon: a short list of essential books that we assume all students and co-workers have read, a short list that summarizes the wisdom of the discipline. A canon can be likened to DNA, be it in music, art, or science, as it carries forward through time the key ideas that have worked in the past. Without a canon, there is no memory of past achievement, no context for appreciating current work, and no way of judging the quality of newer productions. I suggest 20 essential books (the short canon), and 22 complementary readings, for a total of 42 books needed in any young professional's library on plant ecology. [source] If Language Is a Complex Adaptive System, What Is Language Assessment?LANGUAGE LEARNING, Issue 2009Robert J. Mislevy Individuals' use of language in contexts emerges from second-to-second processes of activating and integrating traces of past experiences,an interactionist view compatible with the study of language as a complex adaptive system but quite different from the trait-based framework through which measurement specialists investigate validity, establish reliability, and ensure fairness of assessments. This article discusses assessment arguments from an interactionist perspective. We argue that the familiar concepts and methods of assessment that evolved under a trait perspective can be gainfully reconceived in terms of the finer-grained perspective of interactionism, and we illustrate how key ideas relate to familiar practices in language testing. [source] Under the cobblestones, the beach: the politics and possibilities of the art therapy large groupPSYCHOTHERAPY AND POLITICS INTERNATIONAL, Issue 1 2009Kevin Jones Abstract This paper discusses the politics and possibilities of linking the personal and political with therapeutic and social transformation through a teaching method provided in the art therapy training at Goldsmiths , the art therapy large group (ATLG). Three key ideas of May '68 are related to the ATLG and their relevance to other psychotherapies and psychotherapy trainings is considered. These ideas are: the importance of the ,capitalist' university as an essential terrain in the struggle for social change; the Atelier Populaire's use of art in an anti-capitalist critique of the commodification of art and artist in society, and the anti-imperialist character of the May events. These ideas are related to the theoretical base of the ATLG in the large verbal group literature, Performance Art and to the wide international membership of the ATLG, creating a forum for engaging with global issues. To illustrate these points, we give an example of the interface of the political and the impact of a real event , the university lecturers' strike in 2006 , and the learning that took place in relation to this through the ATLG. We conclude that through a critical engagement with the university within the global terrain of contemporary neoliberalism, the ATLG provides a territory that can integrate the political and therapeutic in arts / psychotherapy trainings; provide a critique and alternative to the commodification of art and artist and engage with issues of difference in the globalized market place. The ATLG prepares the artist / student / therapist / worker to critically engage in the personal and social transformation of the politics of art and psychotherapy provision in the public, private and voluntary sectors. Copyright © 2009 John Wiley & Sons, Ltd. [source] Weberian perspectives on science, technology and the economyTHE BRITISH JOURNAL OF SOCIOLOGY, Issue 3 2002Ralph Schroeder ABSTRACT Several disciplines have contributed to the understanding of the relationship between science, technology, and economic change. Weber's perspective on this relationship, however, has not been properly explored. In the first part of this paper, we give an account of Weber's perspective. In the second part, we critically assess Weber's ideas, indicating those that are useful and those that deserve to be abandoned. We also confront a revised Weberian perspective with those of the main contemporary competitors, the key ideas of economists and economic historians on one side and social constructivists on the other. We conclude that a Weberian comparative-historical approach compares favourably with these competitors, and suggest where his approach still requires further work. [source] Fundamental times, lengths and physical constants: Some unknown contributions by Ettore MajoranaANNALEN DER PHYSIK, Issue 7 2010S. Esposito Abstract We review the introduction in physics of the concepts of an elementary space length and of a fundamental time scale, analyzing some related unknown contributions by Ettore Majorana. In particular, we discuss the quasi-Coulombian scattering in presence of a finite length scale, as well as the introduction of an intrinsic (universal) time delay in the expressions for the retarded electromagnetic potentials. Finally, we also review a special model considered by Majorana in order to deduce the value of the elementary charge, in such a way anticipating key ideas later introduced in quantum electrodynamics. [source] | |||||||||||||||||||