7,840 research outputs found
An Unfinished Canvas: Local Partnerships in Support of Arts Education in California
In 2006, at the request of The William and Flora Hewlett Foundation, SRI International conducted a study aimed at assessing the status of arts education in California relative to state goals. The final report, An Unfinished Canvas. Arts Education in California: Taking Stock of Policy and Practice, revealed a substantial gap between policy and practice. The study found that elementary schools in particular are failing to meet state goals for arts education. In light of these findings, The Hewlett Foundation commissioned a series of follow-up studies to identify policy mechanisms or other means of increasing student access to arts education. This study, focusing on the ability of school districts to leverage support for arts education through partnerships with local arts organizations, is one of the follow-up studies.Partnerships may allow for the pooling of resources and lend support to schools in a variety of ways including artists-in-residency programs, professional development for teachers, exposing students to the arts through the provision of one-time performances at school sites, and organizing field trips to performances and exhibits. According to the California Visual and Performing Arts Framework for California Public Schools, partnerships among districts, schools, and arts organizations are most successful when they are embedded within a comprehensive, articulated program of arts education. Questions about the nature of partnerships that California districts and schools have been able to form with arts organizations, and the success of these partnerships to increase students' access to a sequential standards-based course of study in the four arts disciplines, served as the impetus for this study.A team of SRI researchers conducted case studies of partnerships between districts and arts organizations in six diverse California communities in spring 2008. The case study sites were selected for their particular arts education activities and diverse contexts and, as a result, do not offer generalizable data about partnerships between school districts and arts organizations in California. Instead, we highlight the ways that a sample of partnerships promotes arts education in California elementary schools to inform others who may be interested in building partnerships between school districts and arts organizations
Comments on the 'China model'
This paper reviews the articles by Pan and by Zhu on the China Model. The review of Pan is critical, that of Zhu sympathetic. Pan is criticised for taking an unquestioning attitude towards state supporting ideologies and failing to adequately account for the effects of changes in family structure and class structure in China over the past 50 years. The reviewer broadly agrees with Zhu's comments about a future steady state economy. The article provides statistical data from the recent economic and demographic histories of China and Japan to back up the general conclusions drawn by Zhu
Spin Hall Effect in Doped Semiconductor Structures
In this Letter we present a microscopic theory of the extrinsic spin Hall
effect based on the diagrammatic perturbation theory. Side-jump (SJ) and
skew-scattering (SS) contributions are explicitly taken into account to
calculate the spin Hall conductivity, and we show their effects scale as
, with
being the transport relaxation time. Motivated by recent experimental work we
apply our theory to n- and p-doped 3D and 2D GaAs structures, obtaining
where is the spin Hall
(charge) conductivity, which is in reasonable agreement with the recent
experimental results of Kato \textit{et al}. [Science \textbf{306}, 1910
(2004)] in n-doped 3D GaAs system.Comment: 5 pages, 2 figure
Infrastructure Policy and Economic Growth: Case of Hong Kong
The article argues that in most infrastructure projects, the government has to take up aleading role in managing the development of strategic infrastructure. This article alsodiscusses the value of an integrated approach linking the public and private sectors ininfrastructure investment. Such an integrated approach reflects both the need to buildagreement between various interested parties, and also the strength of the privatesector, whose forces may be effectively combined with foreign ventures. By so doingthe investment risk can be minimised and maximum market efficiency can be achieve
Ensemble of expanded ensembles: A generalized ensemble approach with enhanced flexibility and parallelizability
Over the past decade, alchemical free energy methods like Hamiltonian replica
exchange (HREX) and expanded ensemble (EXE) have gained popularity for the
computation of solvation free energies and binding free energies. These methods
connect the end states of interest via nonphysical pathways defined by states
with different modified Hamiltonians. However, there exist systems where
traversing all alchemical intermediate states is challenging, even if
alchemical biases (e.g., in EXE) or coordinate exchanges (e.g., in HREX) are
applied. This issue is exacerbated when the state space is multidimensional,
which can require extensive communications between hundreds of cores that
current parallelization schemes do not fully support.
To address this challenge, we present the method of ensemble of expanded
ensembles (EEXE), which integrates the principles of EXE and HREX.
Specifically, the EEXE method periodically exchanges coordinates of EXE
replicas sampling different ranges of states and allows combining weights
across replicas. With the solvation free energy calculation of anthracene, we
show that the EEXE method achieves accuracy akin to the EXE and HREX methods in
free energy calculations, while offering higher flexibility in parameter
specification. Additionally, its parallelizability opens the door to wider
applications, such as estimating free energy profiles of serial mutations.
Importantly, extensions to the EEXE approach can be done asynchronously,
allowing looser communications between larger numbers of loosely coupled
processors, such as when using cloud computing, than methods such as replica
exchange. They also allow adaptive changes to the parameters of ensembles in
response to data collected. All algorithms for the EEXE method are available in
the Python package ensemble_md, which offers an interface for EEXE simulation
management without modifying the source code in GROMACS
Glass-Like Heat Conduction in High-Mobility Crystalline Semiconductors
The thermal conductivity of polycrystalline semiconductors with type-I
clathrate hydrate crystal structure is reported. Ge clathrates (doped with Sr
and/or Eu) exhibit lattice thermal conductivities typical of amorphous
materials. Remarkably, this behavior occurs in spite of the well-defined
crystalline structure and relatively high electron mobility (). The dynamics of dopant ions and their interaction with the
polyhedral cages of the structure are a likely source of the strong phonon
scattering.Comment: 4 pages, 3 postscript figures, to be published, Phys. Rev. Let
Doming Modes and Dynamics of Model Heme Compounds
Synchrotron far-IR spectroscopy and density-functional calculations are used to characterize the low-frequency dynamics of model heme FeCO compounds. The “doming” vibrational mode in which the iron atom moves out of the porphyrin plane while the periphery of this ring moves in the opposite direction determines the reactivity of oxygen with this type of molecule in biological systems. Calculations of frequencies and absorption intensities and the measured pressure dependence of vibrational modes in the model compounds are used to identify the doming and related normal modes
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