55 research outputs found

    Atomic spectral-product representations of molecular electronic structure: metric matrices and atomic-product composition of molecular eigenfunctions

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    Recent progress is reported in development of ab initio computational methods for the electronic structures of molecules employing the many-electron eigenstates of constituent atoms in spectral-product forms. The approach provides a universal atomic-product description of the electronic structure of matter as an alternative to more commonly employed valence-bond- or molecular-orbital-based representations. The Hamiltonian matrix in this representation is seen to comprise a sum over atomic energies and a pairwise sum over Coulombic interaction terms that depend only on the separations of the individual atomic pairs. Overall electron antisymmetry can be enforced by unitary transformation when appropriate, rather than as a possibly encumbering or unnecessary global constraint. The matrix representative of the antisymmetrizer in the spectral-product basis, which is equivalent to the metric matrix of the corresponding explicitly antisymmetric basis, provides the required transformation to antisymmetric or linearly independent states after Hamiltonian evaluation. Particular attention is focused in the present report on properties of the metric matrix and on the atomic-product compositions of molecular eigenstates as described in the spectral-product representations. Illustrative calculations are reported for simple but prototypically important diatomic (H_2, CH) and triatomic (H_3, CH_2) molecules employing algorithms and computer codes devised recently for this purpose. This particular implementation of the approach combines Slater-orbital-based one- and two-electron integral evaluations, valence-bond constructions of standard tableau functions and matrices, and transformations to atomic eigenstate-product representations. The calculated metric matrices and corresponding potential energy surfaces obtained in this way elucidate a number of aspects of the spectral-product development, including the nature of closure in the representation, the general redundancy or linear dependence of its explicitly antisymmetrized form, the convergence of the apparently disparate atomic-product and explicitly antisymmetrized atomic-product forms to a common invariant subspace, and the nature of a chemical bonding descriptor provided by the atomic-product compositions of molecular eigenstates. Concluding remarks indicate additional studies in progress and the prognosis for performing atomic spectral-product calculations more generally and efficiently

    A practical, multiplatform app for climate stress to aid animal producers and science education

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    Project Leaders: Michael McKean: Reynolds Journalism Institute (RJI)/Missouri School of Journalism; Dale Musser: Director of the IT Program in the College of Engineering; Ray Massey and Pat Guinan: Commercial Agriculture Program; Ben Gallup: 4-H Center for Youth Development; David Kemp: Future Farmers of America; John Travlos: Electronic Bulletin Board (AgEBB); Stacey Hamilton, Southwest Center, College of Agriculture, Food & Natural Resources"Climate variability is a concern in a number of sectors, particularly in the Agriculture industry. The National Climatic Data Center for the US announced on September 9, 2011 that last summer was the hottest in 75 years, with the greatest impact in Texas and neighboring states of Oklahoma, Kansas, Arkansas and Missouri. The result was daily appearance of news stories regarding losses of livestock and productivity, which during a normal year amount to $897, 369, and 299 million for dairy, beef, and swine industries, respectively. Thermal stress indices have existed for years for these groups, but are underutilized because they require elaborate combinations of environmental (e.g., weather) and physiological (e.g., body temperature) data. There is also increased concern that student interest in science, at both high school and college levels, is declining, and that the United States could be at a disadvantage in solving complex problems of the future such as climate variability due to a lack of qualified scientists. It has been suggested, that the traditional read, recite, regurgitate models for teaching science are ineffective ways to motivate students to learn science, and help them understand and retain science concepts. D.A. Kolb noted that an experiential approach increases interest of youth in science. Experiential learning in the sciences includes gathering the facts surrounding a problem, reflecting on the findings, formulating ideas, and finally testing them, and generating new knowledge. A mechanism to facilitate this process using advanced instructional technologies that are more engaging to a technology-oriented generation of learners will stimulate interest in and learning of science. Our proposal is to develop a native smart phone app (Apple and Android) that combines weather information (both current and projected) with individual animal information to aid the producer in the decision-making process to reduce heat strain and improve animal welfare. At the same time, the app will be a learning device that attracts and stimulates student interest in climate and environmental stress related to themselves and their production animals. Our approach will use students in the "Team-Based Mobile Application Development" course (College of Engineering, IT Program, and School of Journalism) together with CAFNR undergraduate students trained in environmental physiology to develop the prototype. The educational component will require input from a select group of high school/college students in 4-H and FFA (and related agricultural youth organizations), with backgrounds in animal science and a strong interest in using technology to improve animal production and welfare. These students will collaborate with others in the app design and evaluation course for a truly multidisciplinary learning experience. This product will then be promoted, displayed, and tested in select venues, such as CAFNR field days and at the Missouri State Fair." --DescriptionMU Interdisciplinary Innovations Fun

    Delayed self-recognition in children with autism spectrum disorder.

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    This study aimed to investigate temporally extended self-awareness (awareness of oneā€™s place in and continued existence through time) in autism spectrum disorder (ASD), using the delayed self-recognition (DSR) paradigm (Povinelli et al., Child Development 67:1540ā€“1554, 1996). Relative to age and verbal ability matched comparison children, children with ASD showed unattenuated performance on the DSR task, despite showing significant impairments in theory-of-mind task performance, and a reduced propensity to use personal pronouns to refer to themselves. The results may indicate intact temporally extended self-awareness in ASD. However, it may be that the DSR task is not an unambiguous measure of temporally extended self-awareness and it can be passed through strategies which do not require the possession of a temporally extended self-concept

    Human hips, breasts and buttocks: Is fat deceptive?

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    In humans, reproductive-age females, unlike other ages and classes of individuals, deposit fat preferentially on the breasts, hips, and buttocks. This suggests that such fat deposition is a deceptive sexual signal, mimicking other signals of high reproductive value and potential.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/26924/1/0000490.pd

    Self-awareness Part 1: Definition, measures, effects, functions, and antecedents

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    Self-awareness represents the capacity of becoming the object of oneā€™s own attention. In this state one actively identifies, processes, and stores information about the self. This paper surveys the self-awareness literature by emphasizing definition issues, measurement techniques, effects and functions of self-attention, and antecedents of self-awareness. Key self-related concepts (e.g., minimal, reflective consciousness) are distinguished from the central notion of self-awareness. Reviewed measures include questionnaires, implicit tasks, and self-recognition. Main effects and functions of self-attention consist in self-evaluation, escape from the self, amplification of oneā€™s subjective experience, increased self-knowledge, self-regulation, and inferences about othersā€™ mental states (Theory-of-Mind). A neurocognitive and socioecological model of self-awareness is described in which the role of face-to-face interactions, reflected appraisals, mirrors, media, inner speech, imagery, autobiographical knowledge, and neurological structures is underlin

    Passive fear

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    ā€œPassive fearā€ denotes a certain type of response to a perceived threat; what is distinctive about the state of passive fear is that its behavioral outlook appears to qualify the emotional experience. I distinguish between two cases of passive fear: one is that of freezing in fear; the other is that of fear-involved tonic immobility. I reconstruct the explanatory strategy that is commonly employed in the field of emotion science, and argue that it leaves certain questions about the nature of passive fear unanswered. I subsequently propose an account of passive fear that builds upon a phenomenological theory of emotions, placing emphasis on the interpretation of current research into human tonic immobility. Ā© 2014, Springer Science+Business Media Dordrecht
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