46,316 research outputs found
From Anecdote to Evidence: Assessing the Status and Condition of Arts Education at the State Level
Without solid evidence about the status and condition of arts education in the nation's public schools, it is difficult to make a convincing case for the arts. This research and policy brief draws on the experiences of five states -- Illinois, Kentucky, New Jersey, Rhode Island, and Washington -- as the basis for a discussion of various approaches and methodologies for conducting statewide arts education research
Wave Dark Matter and the Tully-Fisher Relation
We investigate a theory of dark matter called wave dark matter, also known as
scalar field dark matter (SFDM) and boson star dark matter or Bose-Einstein
condensate (BEC) dark matter, in spherical symmetry and its relation to the
Tully-Fisher relation. We show that fixing the oscillation frequency of wave
dark matter near the edge of dark galactic halos implies a Tully-Fisher-like
relation for those halos. We then describe how this boundary condition, which
is roughly equivalent to fixing the half-length of the exponentially decaying
tail of each galactic halo mass profile, may yield testable predictions for
this theory of dark matter.Comment: 19 pages, 4 figure
Angiotensin II and VEGF are Involved in Angiogenesis Induced by Short-Term Exercise Training
Results from our laboratory have suggested a pathway involving angiotensin II type 1 (AT1) receptors and vascular endothelial growth factor (VEGF) in angiogenesis induced by electrical stimulation. The present study investigated if similar mechanisms underlie the angiogenesis induced by short-term exercise training. Seven days before training and throughout the training period, male Sprague-Dawley rats received either captopril or losartan in their drinking water. Rats underwent a 3-day treadmill training protocol. The tibialis anterior and gastrocnemius muscles were harvested under anesthesia and lightly fixed in formalin (vessel density) or frozen in liquid nitrogen (VEGF expression). In controls, treadmill training resulted in a significant increase in vessel density in all muscles studied. However, the angiogenesis induced by exercise was completely blocked by either losartan or captopril. Western blot analysis showed that VEGF expression was increased in the exercised control group, and both losartan and captopril blocked this increase. The role of VEGF was directly confirmed using a VEGF-neutralizing antibody. These results confirm the role of angiotensin II and VEGF in angiogenesis induced by exercise
PC-based aviation training devices (PCATDs): research, development and certification
This paper examines the development of two PCATD’s (one
helicopter, one fixed-wing) and their eventual certification by CAA.
Certification has demonstrated the potential these devices have for aviation
training in New Zealand. Traditionally FTD‘s and PCATD’s have been
sourced from foreign companies, and they represent a considerable financial
investment for large flying training organisations. The procurement of these
simulator types is generally beyond the financial resources of most small to
medium sized flying schools. Aviation training in NZ is facing significant
financial constraints as well as an increasing demand to simulate complex
glass cockpit systems that are now installed in most new General Aviation
(GA) aircraft. The development, utilisation and certification of this type of
PCATD technology could solve these difficult challenges
Scotland as an Optimal Currency Area
Since the Scottish independence movement has reached the point that there will be a referendum on Scottish independence this September, the issue of whether the Scotland is optimal currency areas is very topical.In this paper we review the microeconomic foundations of an optimal currency area. We test these microeconomic foundations. We find that the UK, Scotland and the UK without Scotland meet the microeconomic criteria for a common currency area. While adopting a common currency is ultimately a political decision, these results imply that the broadest of these areas, the UK, is the optimal currency area in the sense of minimizing transactions costs.We do find differences in the UK less Scotland and Scotland economies in loan data. We further find that neither the euro bloc nor the euro bloc including Scotland meet the microeconomic criteria for a common currency area. In the event of a “yes” vote for Scottish independence, the immediate problem facing the Scottish government is to decide on an exchange rate regime that is seen as credible by the financial markets to avoid a flight of capital. How policymakers chooses between alternative exchange rate regimes is currently a topic for hot debate in central banking circles and the process of a monetary union breaking up is a fascinating area worthy of future research
Redox supercapacitor performance of nanocrystalline molybdenum nitrides obtained by ammonolysis of chloride- and amide-derived precursors
Reactions of MoCl5 or Mo(NMe2)4 with ammonia result in cubic ?-Mo2N or hexagonal ?1-MoN depending on reaction time and temperature. At moderate temperatures the cubic product from Mo(NMe2)4 exhibits lattice distortions. Fairly high surface areas are observed in the porous particles of the chloride-derived materials and high capacitances of up to 275 F g?1 are observed when electrodes made from them are cycled in aqueous H2SO4 or K2SO4 electrolytes. The cyclic voltammograms suggest charge is largely stored in the electrochemical double layer at the surface of these materials. Amide-derived molybdenum nitrides have relatively low surface areas and smaller capacitances, but do exhibit strong redox features in their cyclic voltammograms, suggesting that redox capacitance is responsible for a significant proportion of the charge stored
Current driven quantum criticality in itinerant electron ferromagnets
We determine the effect of an in-plane current flow on the critical
properties of a 2d itinerant electron system near a ferromagnetic-paramagnetic
quantum critical point. We study a model in which a nonequilibrium steady state
is established as a result of exchange of particles and energy with an
underlying substrate. the current gives rise not only to an effective
temperature equal to the voltage drop over a distance of order the mean free
path, but also to symmetry breaking terms of the form in the effective action. The effect of the symmetry breaking on
the fluctuational and critical properties is found to be small although (in
agreement with previous results) if rotational degrees of freedom are
important, the current can make the classically ordered state dynamically
unstable.Comment: 4 pages, published versio
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