7,584 research outputs found
How pharmacoepidemiology networks can manage distributed analyses to improve replicability and transparency and minimize bias
Several pharmacoepidemiology networks have been developed over the past decade that use a distributed approach, implementing the same analysis at multiple data sites, to preserve privacy and minimize data sharing. Distributed networks are efficient, by interrogating data on very large populations. The structure of these networks can also be leveraged to improve replicability, increase transparency, and reduce bias. We describe some features of distributed networks using, as examples, the Canadian Network for Observational Drug Effect Studies, the Sentinel System in the USA, and the European Research Network of Pharmacovigilance and Pharmacoepidemiology. Common protocols, analysis plans, and data models, with policies on amendments and protocol violations, are key features. These tools ensure that studies can be audited and repeated as necessary. Blinding and strict conflict of interest policies reduce the potential for bias in analyses and interpretation. These developments should improve the timeliness and accuracy of information used to support both clinical and regulatory decisions
Advanced Microwave Precipitation Radiometer (AMPR) for remote observation of precipitation
The design, development, and tests of the Advanced Microwave Precipitation Radiometer (AMPR) operating in the 10 to 85 GHz range specifically for precipitation retrieval and mesoscale storm system studies from a high altitude aircraft platform (i.e., ER-2) are described. The primary goals of AMPR are the exploitation of the scattering signal of precipitation at frequencies near 10, 19, 37, and 85 GHz together to unambiguously retrieve precipitation and storm structure and intensity information in support of proposed and planned space sensors in geostationary and low earth orbit, as well as storm-related field experiments. The development of AMPR will have an important impact on the interpretation of microwave radiances for rain retrievals over both land and ocean for the following reasons: (1) A scanning instrument, such as AMPR, will allow the unambiguous detection and analysis of features in two dimensional space, allowing an improved interpretation of signals in terms of cloud features, and microphysical and radiative processes; (2) AMPR will offer more accurate comparisons with ground-based radar data by feature matching since the navigation of the ER-2 platform can be expected to drift 3 to 4 km per hour of flight time; and (3) AMPR will allow underflights of the SSM/I satellite instrument with enough spatial coverage at the same frequencies to make meaningful comparisons of the data for precipitation studies
Spin-triplet superconductivity in a weak-coupling Hubbard model for the quasi-one-dimensional compound LiMoO
The purple bronze LiMoO is of interest due to its
quasi-one-dimensional electronic structure and the possible Luttinger liquid
behavior resulting from it. For sufficiently low temperatures, it is a
superconductor with a pairing symmetry that is still to be determined. To shed
light on this issue, we analyze a minimal Hubbard model for this material
involving four molybdenum orbitals per unit cell near quarter filling, using
asymptotically exact perturbative renormalization group methods. We find that
spin triplet odd-parity superconductivity is the dominant instability.
Approximate nesting properties of the two quasi-one-dimensional Fermi surfaces
enhance certain second-order processes, which play crucial roles in determining
the structure of the pairing gap. Notably, we find that the gap has accidental
nodes, i.e. it has more sign changes than required by the point-group symmetry.Comment: Update
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Cover, Contents, Acknowledgments, and Introduction, Humanizing the Exploding Metropolis
Cover, Contents, Acknowledgments, and Introduction, Humanizing the Exploding Metropolis for Rutherford H. Platt\u27s book, The Humane Metropolis: People and Nature in the 21st-Century Cit
Letter from H. V. Platt to [John Muir], [ca. 1907].
Form 2191 C. B. After transmitting telegrams which in their judgment would have served the Company\u27s interest if sent by train mail, or appear unnecessarily long operators are required to attach a copy of them to proper Form and forward and forward same to Superintendent of Telegraph.3:10PM Pink Yum8 13thCendr No 8.Please advice Mr. John Muir on your train wait at ImperialJet for Mr. Hrrimans Special.H V Platt0400
Full Lyapunov Exponent Placement in Reentry Trajectories
This study investigated the ability to control the chaotic reentry of a Delta-Clipper like vehicle by setting the values of initial arid final principal dynamical directions as well as the Lyapunov exponents. A model of the original controlled reentry vehicle was created through the use of the equations of motion in conjunction with an atmospheric model. A modified linear quadratic regulator allowed the set up of a boundary value problem which specified the Lyapunov exponents and determined the gain matrix as a function of time. The gain matrix can eventually be used in the control system of the vehicle
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The Humane Metropolis: People and Nature in the 21st-Century City [full book]
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