2,809 research outputs found

    Undergraduate music students' perceptions of lesson and rehearsal planning /

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    This dissertation comprises three projects that were designed to investigate specific lesson planning practices and how music teacher educators might improve students' instructional preparation. The first investigation is a review of literature pertaining to lesson planning and teacher knowledge-specifically Pedagogical Content Knowledge (PCK) and Content Knowledge (CK). The second investigation is a survey study about preservice teachers' perceptions of where in their coursework lesson plans were taught and used, beliefs regarding the importance of planning, and how prepared they felt to use lesson planning in their classes. Respondents (N equals 107) indicated that they were taught lesson planning more often in music education courses than in general education or music method courses. The third investigation is an experimental study. Novice conductors (N equals 20) were randomly divided into two equal groups (n equals 10 per group). I sought to determine whether novices who focused their rehearsal preparation using typical score study methodologies (CK) differed from those whose preparation involved both score study and specific rehearsal strategies (CK and PCK). I found no significant differences between the control and experimental groups' score study knowledge or rehearsal effectiveness ratings. Results from these three projects indicated that preservice teachers (a) found lesson planning to be important, (b) felt prepared to use lesson plans as part of the instructional process, and (c) could use either preparation method to prepare for rehearsals.Dr. Brian Silvey, Dissertation Advisor.|Includes vita.Includes bibliographical references (pages 76-95)

    Tunneling through nanosystems: Combining broadening with many-particle states

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    We suggest a new approach for transport through finite systems based on the Liouville equation. By working in a basis of many-particle states for the finite system, Coulomb interactions are taken fully into account and correlated transitions by up to two different contact states are included. This latter extends standard rate equation models by including level-broadening effects. The main result of the paper is a general expression for the elements of the density matrix of the finite size system, which can be applied whenever the eigenstates and the couplings to the leads are known. The approach works for arbitrary bias and for temperatures above the Kondo temperature. We apply the approach to standard models and good agreement with other methods in their respective regime of validity is found.Comment: 9 pages, 5 figures included to tex

    Quantitative trait loci mapping reveals candidate pathways regulating cell cycle duration in \u3cem\u3ePlasmodium falciparum\u3c/em\u3e

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    Background: Elevated parasite biomass in the human red blood cells can lead to increased malaria morbidity. The genes and mechanisms regulating growth and development of Plasmodium falciparum through its erythrocytic cycle are not well understood. We previously showed that strains HB3 and Dd2 diverge in their proliferation rates, and here use quantitative trait loci mapping in 34 progeny from a cross between these parent clones along with integrative bioinformatics to identify genetic loci and candidate genes that control divergences in cell cycle duration. Results: Genetic mapping of cell cycle duration revealed a four-locus genetic model, including a major genetic effect on chromosome 12, which accounts for 75% of the inherited phenotype variation. These QTL span 165 genes, the majority of which have no predicted function based on homology. We present a method to systematically prioritize candidate genes using the extensive sequence and transcriptional information available for the parent lines. Putative functions were assigned to the prioritized genes based on protein interaction networks and expression eQTL from our earlier study. DNA metabolism or antigenic variation functional categories were enriched among our prioritized candidate genes. Genes were then analyzed to determine if they interact with cyclins or other proteins known to be involved in the regulation of cell cycle. Conclusions: We show that the divergent proliferation rate between a drug resistant and drug sensitive parent clone is under genetic regulation and is segregating as a complex trait in 34 progeny. We map a major locus along with additional secondary effects, and use the wealth of genome data to identify key candidate genes. Of particular interest are a nucleosome assembly protein (PFL0185c), a Zinc finger transcription factor (PFL0465c) both on chromosome 12 and a ribosomal protein L7Ae-related on chromosome 4 (PFD0960c)

    Gain without inversion in a biased superlattice

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    Intersubband transitions in a superlattice under homogeneous electric field is studied within the tight-binding approximation. Since the levels are equi-populated, the non-zero response appears beyond the Born approximation. Calculations are performed in the resonant approximation with scattering processes exactly taken into account. The absorption coefficient is equal zero for the resonant excitation while a negative absorption (gain without inversion) takes place below the resonance. A detectable gain in the THz spectral region is obtained for the low-doped GaAsGaAs-based superlattice and spectral dependencies are analyzed taking into account the interplay between homogeneous and inhomogeneous mechanisms of broadening.Comment: 6 pages, 4 figure

    On apparent breaking the second law of thermodynamics in quantum transport studies

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    We consider a model for stationary electronic transport through a one-dimensional chain of two leads attached to a perturbed central region (quantum dot) in the regime where the theory proposed recently by Capek for a similar model of phonon transport predicts the striking phenomenon of a permanent current between the leads. This result based on a rigorous but asymptotic Davies theory is at variance with the zero current yielded by direct transport calculations which can be carried out in the present model. We find the permanent current to be within the error of the asymptotic expansion for finite couplings, and identify cancelling terms of the same order.Comment: 5 pages, 3 figure

    Perioperative Strategien zur Regulierung des Sympathikotonus

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    Zusammenfassung: Obwohl für verschiedene therapeutische Konzepte zur Verminderung der kardialen perioperativen Morbidität und Mortalität zunehmend Evidenz vorliegt, bleibt die tatsächliche Umsetzung solcher Konzepte im klinischen Alltag oft aus. Zwar ist einem großen Teil der klinisch tätigen Ärzte die wachsende Literatur bekannt; dieses Wissen wird aber nur in einem Teil der Fälle angewendet, selbst wenn allgemein akzeptierte Indikationen bestehen. Die vorliegende Übersichtsarbeit hat deshalb zum Ziel, die Gründe für die mangelnde Umsetzung aufzuzeigen und nochmals die wesentlichen Grundlagen sowie die klinische Bedeutung einzelner Strategien einschließlich des α2-Agonismus, der β-adrenergen Blockade und der Regionalanästhesien zusammenzufassen. Dies insbesondere im Hinblick auf die klinische Anwendung dieser Konzepte in einem allgemeinanästhesiologischen Umfeld. Zudem wird ein Ausblick in die auf "gene profiling" basierende individualisierte Pharmakotherapie der perioperativen Medizin von morgen gegebe

    A "Littlest Higgs" Model with Custodial SU(2) Symmetry

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    In this note, a ``littlest higgs'' model is presented which has an approximate custodial SU(2) symmetry. The model is based on the coset space SO(9)/(SO(5)Ă—SO(4))SO(9)/(SO(5)\times SO(4)). The light pseudo-goldstone bosons of the theory include a {\it single} higgs doublet below a TeV and a set of three SU(2)WSU(2)_W triplets and an electroweak singlet in the TeV range. All of these scalars obtain approximately custodial SU(2) preserving vacuum expectation values. This model addresses a defect in the earlier SO(5)Ă—SU(2)Ă—U(1)SO(5)\times SU(2)\times U(1) moose model, with the only extra complication being an extended top sector. Some of the precision electroweak observables are computed and do not deviate appreciably from Standard Model predictions. In an S-T oblique analysis, the dominant non-Standard Model contributions are the extended top sector and higgs doublet contributions. In conclusion, a wide range of higgs masses is allowed in a large region of parameter space consistent with naturalness, where large higgs masses requires some mild custodial SU(2) violation from the extended top sector.Comment: 22 pages + 8 figures; JHEP style, added references and extra discussion on size of T contributions, as well as some other minor clarifications. Version to appear in JHE

    Boolean Network Topologies and the Determinative Power of Nodes

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    Boolean networks have been used extensively for modeling networks whose node activity could be simplified to a binary outcome, such as on-off. Each node is influenced by the states of the other nodes via a logical Boolean function. The network is described by its topological properties which refer to the links between nodes, and its dynamical properties which refer to the way each node uses the information obtained from other nodes to update its state. This work explores the correlation between the information stored in the Boolean functions for each node in a property known as the determinative power and some topological properties of each node, in particular the clustering coefficient and the betweenness centrality. The determinative power of nodes is defined using concepts from information theory, in particular the mutual information. The primary motivation is to construct models of real world networks to examine if the determinative power is sensitive to any of the considered topological properties. The findings indicate that, for a homogeneous network in which all nodes obey the same threshold function under three different topologies, the determinative power can have a negative correlation with the clustering coefficient and a positive correlation with the betweenness centrality, depending on the topological properties of the network. A statistical analysis on a collection of 36 Boolean models of signal transduction networks reveals that the correlations observed in the theoretical cases are suppressed in the biological networks, thus supporting previous research results

    Current-voltage characteristic and stability in resonant-tunneling n-doped semiconductor superlattices

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    We review the occurrence of electric-field domains in doped superlattices within a discrete drift model. A complete analysis of the construction and stability of stationary field profiles having two domains is carried out. As a consequence, we can provide a simple analytical estimation for the doping density above which stable stable domains occur. This bound may be useful for the design of superlattices exhibiting self-sustained current oscillations. Furthermore we explain why stable domains occur in superlattices in contrast to the usual Gunn diode.Comment: Tex file and 3 postscript figure
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