2,691 research outputs found
Passive dual spin misalignment compensators
A combination dual-spin gyroscopically stabilized device is described having a spinning rotor and a non-spinning platform. Two substantially lossless mechanical resonators, resonant at the spin frequency, are orthogonally positioned on the platform for compensation for the disturbing torque acting on the platform due to rotor misalignment
Study of flight management requirements during SST low visibility approach and landing operations. Volume 1 - Definition of baseline SST landing system
Baseline instrument landing system for low visibility approach and landing of supersonic transport
Improving ICT governance in Australian companies
This paper begins with the Australian Standard for the Corporate Governance of Information and Communication Technology (ICT) AS8015 (Standards Australia, 2005) and presents research findings that can be applied as recommendations to enhance the effective implementation of this Standard’s principles within an organisation. These recommendations relating to the principles outlined within the Standard concern such factors as, identifying and addressing issues surrounding the implementation of this Standard and the actions that could be undertaken to improve the effectiveness of ICT governance by sharply focusing upon the governance aspects of ICT within business, as opposed to the management aspect of ICT
Applications of neuroimaging to disease-modification trials in Alzheimer's disease.
Critical to development of new therapies for Alzheimer's disease (AD) is the ability to detect clinical or pathological change over time. Clinical outcome measures typically used in therapeutic trials have unfortunately proven to be relatively variable and somewhat insensitive to change in this slowly progressive disease. For this reason, development of surrogate biomarkers that identify significant disease-associated brain changes are necessary to expedite treatment development in AD. Since AD pathology is present in the brain many years prior to clinical manifestation, ideally we want to develop biomarkers of disease that identify abnormal brain structure or function even prior to cognitive decline. Magnetic resonance imaging, fluorodeoxyglucose positron emission tomography, new amyloid imaging techniques, and spinal fluid markers of AD all have great potential to provide surrogate endpoint measures for AD pathology. The Alzheimer's disease neuroimaging initiative (ADNI) was developed for the distinct purpose of evaluating surrogate biomarkers for drug development in AD. Recent evidence from ADNI demonstrates that imaging may provide more sensitive, and earlier, measures of disease progression than traditional clinical measures for powering clinical drug trials in Alzheimer's disease. This review discusses recently presented data from the ADNI dataset, and the importance of imaging in the future of drug development in AD
Self-assembly of the simple cubic lattice with an isotropic potential
Conventional wisdom presumes that low-coordinated crystal ground states
require directional interactions. Using our recently introduced optimization
procedure to achieve self-assembly of targeted structures (Phys. Rev. Lett. 95,
228301 (2005), Phys. Rev. E 73, 011406 (2006)), we present an isotropic pair
potential for a three-dimensional many-particle system whose classical
ground state is the low-coordinated simple cubic (SC) lattice. This result is
part of an ongoing pursuit by the authors to develop analytical and
computational tools to solve statistical-mechanical inverse problems for the
purpose of achieving targeted self-assembly. The purpose of these methods is to
design interparticle interactions that cause self-assembly of technologically
important target structures for applications in photonics, catalysis,
separation, sensors and electronics. We also show that standard approximate
integral-equation theories of the liquid state that utilize pair correlation
function information cannot be used in the reverse mode to predict the correct
simple cubic potential. We report in passing optimized isotropic potentials
that yield the body-centered cubic and simple hexagonal lattices, which provide
other examples of non-close-packed structures that can be assembled using
isotropic pair interactions.Comment: 16 pages, 12 figures. Accepted for publication in Physical Review
Reforming Reimbursement for the US Food and Drug Administration’s Accelerated Approval Program to Support State Medicaid Programs
Importance The US Food and Drug Administration (FDA) has an accelerated approval program that has become the subject of scholarly attention and criticism, not only for the FDA’s oversight of the program but also for its implications for payers.
Observations State Medicaid programs’ legal obligations to provide reimbursement for accelerated approval products have created fiscal challenges for Medicaid that have been exacerbated by industry’s changing use of the accelerated approval program over time. Although strategies for accelerated approval reforms have been proposed, most focus on reforming the FDA’s accelerated approval pathway and product regulation without taking into account the implications of this pathway for state Medicaid programs. There is a need for policy reforms that balance the goal of speeding approval of important medicines with states’ real concerns regarding spending on medications with little evidence of clinical benefits. Areas of potential reform include formulary exclusion, Medicaid rebates, value-based pricing, and consolidated purchasing or carve outs.
Conclusions and Relevance Policy makers may wish to consider options for reforming reimbursement for accelerated approval products in addition to reforms to the FDA’s operation of the pathway. Policy reform proposals can provide a range of options to evaluate trade-offs of access and pricing
What Can Hydrography Between the New England Slope, Bermuda and Africa Tell us About the Strength of the AMOC Over the Last 90 years?
The Gulf Stream is the only pathway in the subtropical North Atlantic by which warm water flows poleward. This transport of warm water and return of cold water at depth is called the Atlantic Meridional Overturning Circulation (AMOC). The dynamic method is applied to hydrocasts collected since the 1930s to estimate upper-ocean transport (0–1,000 m) between the U.S. Continental Slope and Bermuda and separately to Africa with focus on the longest directly observable timescale. Calculating transport between the Slope and Bermuda eliminates the Gulf Stream\u27s northern and southern recirculation gyres, while calculations between the Slope and Africa remove all other recirculating geostrophic flow. The net Slope-Bermuda upper-ocean transport is estimated to be 41.1 ± 0.4 Sv, decreasing by 2.0 ± 0.8 Sv between 1930 and 2020. The AMOC contribution is 18.4 ± 0.6 Sv, decreasing by 0.4 ± 0.6 Sv between 1930 and 2020
Seizing the Moment: Realizing the Promise of Student-Centered Learning
This brief outlines policy recommendations for supporting student-centered learning at the local, state, and federal level
New Pseudo-Phase Structure for -Pu
In this paper we propose a new pseudo-phase crystal structure, based on an
orthorhombic distortion of the diamond structure, for the ground-state
-phase of plutonium. Electronic-structure calculations in the
generalized-gradient approximation give approximately the same total energy for
the two structures. Interestingly, our new pseudo-phase structure is the same
as the Pu -phase structure except with very different b/a and c/a
ratios. We show how the contraction relative to the phase, principally
in the direction, leads to an -like structure in the [0,1,1] plane.
This is an important link between two complex structures of plutonium and opens
new possibilities for exploring the very rich phase diagram of Pu through
theoretical calculations
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