361 research outputs found
Characterizing SWCNT Dispersion in Polymer Composites
The new wave of single wall carbon nanotube (SWCNT) infused composites will yield structurally sound multifunctional nanomaterials. The SWCNT network requires thorough dispersion within the polymer matrix in order to maximize the benefits of the nanomaterial. However, before any nanomaterials can be used in aerospace applications a means of quality assurance and quality control must be certified. Quality control certification requires a means of quantification, however, the measurement protocol mandates a method of seeing the dispersion first. We describe here the new tools that we have developed and implemented to first be able to see carbon nanotubes in polymers and second to measure or quantify the dispersion of the nanotubes
Factorization, Effective Field Theory, and B-> D^(*) X Decays
In this proceedings I review the soft-collinear effective theory (SCET), an
effective theory for energetic particles. I also discuss factorization in
exclusive and inclusive B-> D^(*)X decays, and tests which can help distinguish
whether factorization is a result of a large energy limit, the large N_c limit,
or a combination of the two.Comment: 7 pages, 3 figs, Invited plenary talk at the 5th International
Conference on Hyperons, Charm, and Beauty Hadrons, Vancouver, June 200
Development of a Pharmacodynamic Model of Murine Malaria
The rational design of antimalarial therapies has historically been compromised by a paucity of pharmacodynamic data contributing to resistance through deployment of suboptimal doses. This thesis demonstrates a modified P. berghei murine malaria model for collecting detailed in vivo pharmacodynamic data and novel in silico mathematical model enabling optimisation of dosing and combination therapy. These models contribute to preclinical knowledge and provide the potential to assist in the development of methods to optimise clinical treatment
Polytypic Genetic Programming
Program synthesis via heuristic search often requires a great deal of boilerplate code to adapt program APIs to the search mechanism. In addition, the majority of existing approaches are not type-safe: i.e. they can fail at runtime because the search mechanisms lack the strict type information often available to the compiler. In this article, we describe Polytope, a Scala framework that uses polytypic programming, a relatively recent advance in program abstraction. Polytope requires a minimum of boilerplate code and supports a form of strong-typing in which type rules are automatically enforced by the compiler, even for search operations such as mutation which are applied at run-time. By operating directly on language-native expressions, it provides an embeddable optimization procedure for existing code. We give a tutorial example of the specific polytypic approach we adopt and compare both runtime efficiency and required lines of code against the well-known EpochX GP framework, showing comparable performance in the former and the complete elimination of boilerplate for the latter
Multi-Functional BN-BN Composite
Multifunctional Boron Nitride nanotube-Boron Nitride (BN-BN) nanocomposites for energy transducers, thermal conductors, anti-penetrator/wear resistance coatings, and radiation hardened materials for harsh environments. An all boron-nitride structured BN-BN composite is synthesized. A boron nitride containing precursor is synthesized, then mixed with boron nitride nanotubes (BNNTs) to produce a composite solution which is used to make green bodies of different forms including, for example, fibers, mats, films, and plates. The green bodies are pyrolized to facilitate transformation into BN-BN composite ceramics. The pyrolysis temperature, pressure, atmosphere and time are controlled to produce a desired BN crystalline structure. The wholly BN structured materials exhibit excellent thermal stability, high thermal conductivity, piezoelectricity as well as enhanced toughness, hardness, and radiation shielding properties. By substituting with other elements into the original structure of the nanotubes and/or matrix, new nanocomposites (i.e., BCN, BCSiN ceramics) which possess excellent hardness, tailored photonic bandgap and photoluminescence, result
CP Violation and Flavour Mixing in the Standard Model -- 1996 Update
We review and update the constraints on the parameters of the quark flavour
mixing matrix in the standard model and estimate the resulting CP
asymmetries in decays, taking into account recent experimental and
theoretical developments. With the updated CKM matrix we present the
currently-allowed range of the ratios and ,
as well as the standard model predictions for the \bsbsbar\ mixing parameter
\xs (or, equivalently, \delms) and the quantities , and , which characterize the CP-asymmetries in
-decays.Comment: 23 pages, LaTeX, 9 figures; updated to include latest experimental
results on Bs-Bs(bar) mixin
Four-nucleon contact interactions from holographic QCD
We calculate the low energy constants of four-nucleon interactions in an
effective chiral Lagrangian in holographic QCD. We start with a D4-D8 model to
obtain meson-nucleon interactions and then integrate out massive mesons to
obtain the four-nucleon interactions in 4D. We end up with two low energy
constants at the leading order and seven of them at the next leading order,
which is consistent with the effective chiral Lagrangian. The values of the low
energy constants are evaluated with the first five Kaluza-Klein resonances.Comment: 28 page
Dispersive Bounds on the Shape of B -> D^(*) l nu Form Factors
Dispersive constraints on the shape of the form factors which describe the
exclusive decays B -> D^(*) l nu are derived by fully exploiting spin symmetry
in the ground-state doublet of heavy-light mesons. The analysis includes all
twenty B^(*) -> D^(*) semileptonic form factors. Heavy-quark symmetry, with
both short-distance and 1/m_Q corrections included, is used to provide
relations between the form factors near zero recoil. Simple one-parameter
functions are derived, which describe the form factors in the semileptonic
region with an accuracy of better than 2%. The implications of our results for
the determination of |V_cb| are discussed.Comment: 32 pages, 6 figure
Nature tourism and Irish film
This article provides a historical overview and reading of seminal Irish film from the perspective of nature tourism. Within Irish cultural studies, tourism is frequently equated with an overly romantic image of the island, which has been used to sell the country abroad. However, using notions like the tourist gaze and taking on board influential debates around space/place, one can posit a more progressive environmental vision of nature and landscape in our readings of film
Toward optimal implementation of cancer prevention and control programs in public health: A study protocol on mis-implementation
Abstract Background Much of the cancer burden in the USA is preventable, through application of existing knowledge. State-level funders and public health practitioners are in ideal positions to affect programs and policies related to cancer control. Mis-implementation refers to ending effective programs and policies prematurely or continuing ineffective ones. Greater attention to mis-implementation should lead to use of effective interventions and more efficient expenditure of resources, which in the long term, will lead to more positive cancer outcomes. Methods This is a three-phase study that takes a comprehensive approach, leading to the elucidation of tactics for addressing mis-implementation. Phase 1: We assess the extent to which mis-implementation is occurring among state cancer control programs in public health. This initial phase will involve a survey of 800 practitioners representing all states. The programs represented will span the full continuum of cancer control, from primary prevention to survivorship. Phase 2: Using data from phase 1 to identify organizations in which mis-implementation is particularly high or low, the team will conduct eight comparative case studies to get a richer understanding of mis-implementation and to understand contextual differences. These case studies will highlight lessons learned about mis-implementation and identify hypothesized drivers. Phase 3: Agent-based modeling will be used to identify dynamic interactions between individual capacity, organizational capacity, use of evidence, funding, and external factors driving mis-implementation. The team will then translate and disseminate findings from phases 1 to 3 to practitioners and practice-related stakeholders to support the reduction of mis-implementation. Discussion This study is innovative and significant because it will (1) be the first to refine and further develop reliable and valid measures of mis-implementation of public health programs; (2) bring together a strong, transdisciplinary team with significant expertise in practice-based research; (3) use agent-based modeling to address cancer control implementation; and (4) use a participatory, evidence-based, stakeholder-driven approach that will identify key leverage points for addressing mis-implementation among state public health programs. This research is expected to provide replicable computational simulation models that can identify leverage points and public health system dynamics to reduce mis-implementation in cancer control and may be of interest to other health areas
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