To Reform Medicare, Reform Incentives and Organization

Alain C. Enthoven's paper, To Reform Medicare, Reform Incentives And Organization, explains how the principles of cost-responsible consumer choice among competing health-insurance plans, sometimes called "managed competition," can both improve quality and reduce cost in the federal government's Medicare program

Molecular propensity as a driver for explorative reactivity studies

Quantum chemical studies of reactivity involve calculations on a large number of molecular structures and comparison of their energies. Already the set-up of these calculations limits the scope of the results that one will obtain, because several system-specific variables such as the charge and spin need to be set prior to the calculation. For a reliable exploration of reaction mechanisms, a considerable number of calculations with varying global parameters must be taken into account, or important facts about the reactivity of the system under consideration can go undetected. For example, one could miss crossings of potential energy surfaces for different spin states or might not note that a molecule is prone to oxidation. Here, we introduce the concept of molecular propensity to account for the predisposition of a molecular system to react across different electronic states in certain nuclear configurations. Within our real-time quantum chemistry framework, we developed an algorithm that allows us to be alerted to such a propensity of a system under consideration.Comment: 10 pages, 7 figure

Realization of a Laser Cooled Microwave Power Standard (conference digest)

We demonstrate the feasibility of a novel microwave power standard based on the electromagnetic interaction with cold atoms. Under the effect of the radiation, the internal state populations will undergo a Rabi oscillation. The measurement of its frequency will allow the determination of the electromagnetic field strength.Comment: 2 pages, 1 figur

Large restricted sumsets in general abelian group

Let A, B and S be three subsets of a finite Abelian group G. The restricted sumset of A and B with respect to S is defined as A\wedge^{S} B= {a+b: a in A, b in B and a-b not in S}. Let L_S=max_{z in G}| {(x,y): x,y in G, x+y=z and x-y in S}|. A simple application of the pigeonhole principle shows that |A|+|B|>|G|+L_S implies A\wedge^S B=G. We then prove that if |A|+|B|=|G|+L_S then |A\wedge^S B|>= |G|-2|S|. We also characterize the triples of sets (A,B,S) such that |A|+|B|=|G|+L_S and |A\wedge^S B|= |G|-2|S|. Moreover, in this case, we also provide the structure of the set G\setminus (A\wedge^S B).Comment: Paper submitted November 15, 2011. To appear European Journal of Combinatorics, special issue in memorian Yahya ould Hamidoune (2013

Accuracy of an Atomic Microwave Power Standard

We have built an atomic microwave power standard based on the electromagnetic interaction with laser-cooled atoms. The atoms traversed a waveguide transmission line, and under the effect of the radiation, the internal state populations underwent a Rabi flopping oscillation. Measurement of the oscillation frequency allowed the determination of the incident microwave power. As many of 60 oscillations were observed over a dynamic range of 20 dB and the standard deviation of the measurements was about 0.02%. The measured frequency was compared to a calculated one and an agreement of 1.3% with an uncertainty of 5% (rectangular) was found.Comment: 5 figure