Evaluating the Effects of Large Scale Health Interventions in Developing Countries: The Zambian Malaria Initiative

Since 2003, Zambia has been engaged in a large-scale, centrally coordinated national anti- Malaria campaign which has become a model in sub-Saharan Africa. This paper aims at quantifying the individual and macro level benefits of this campaign, which involved mass distribution of insecticide treated mosquito nets, intermittent preventive treatment for pregnant women, indoor residual spraying, rapid diagnostic tests, and artemisinin-based combination therapy. We discuss the timing and regional coverage of the program, and critically review the available health and program rollout data. To estimate the health benefits associated with the program rollout, we use both population based morbidity measures from the Demographic and Health Surveys and health facility based mortality data as reported in the national Health Management Information System. While we find rather robust correlations between the rollout of bed nets and subsequent improvements in our health measures, the link between regional spraying and individual level health appears rather weak in the data.

On the spectrum of the magnetohydrodynamic mean-field alpha^2-dynamo operator

The existence of magnetohydrodynamic mean-field alpha^2-dynamos with spherically symmetric, isotropic helical turbulence function alpha is related to a non-self-adjoint spectral problem for a coupled system of two singular second order ordinary differential equations. We establish global estimates for the eigenvalues of this system in terms of the turbulence function alpha and its derivative alpha'. They allow us to formulate an anti-dynamo theorem and a non-oscillation theorem. The conditions of these theorems, which again involve alpha and alpha', must be violated in order to reach supercritical or oscillatory regimes.Comment: 35 pages, 4 figures, to be published in SIAM J. Math. Anal

Hybrid III-V/Si distributed-feedback laser based on adhesive bonding

A hybrid evanescently coupled III-V/silicon distributed-feedback laser with an integrated monitor photodiode, based on adhesive divinyl siloxane-benzocyclobutene bonding and emitting at 1310 nm, is presented. An output power of similar to 2.85 mW is obtained in a continuous wave regime at 10 degrees C. The threshold current is 20 mA and a sidemode suppression ratio of 45 dB is demonstrated. Optical feedback is provided via corrugations on top of the silicon rib waveguide, while a specially developed bonding procedure yields 40-nm-thick adhesive bonding layers, enabling efficient evanescent coupling

Bouncing inflation in nonlinear R2+R4R^2+R^4 gravitational model

We study a gravitational model with curvature-squared $R^2$ and curvature-quartic $R^4$ nonlinearities. The effective scalar degree of freedom $\phi$ (scalaron) has a multi-valued potential $U(\phi)$ consisting of a number of branches. These branches are fitted with each other in the branching and monotonic points. In the case of four-dimensional space-time, we show that the monotonic points are penetrable for scalaron while in the vicinity of the branching points scalaron has the bouncing behavior and cannot cross these points. Moreover, there are branching points where scalaron bounces an infinite number of times with decreasing amplitude and the Universe asymptotically approaches the de Sitter stage. Such accelerating behavior we call bouncing inflation. For this accelerating expansion there is no need for original potential $U(\phi)$ to have a minimum or to check the slow-roll conditions. A necessary condition for such inflation is the existence of the branching points. This is a new type of inflation. We show that bouncing inflation takes place both in the Einstein and Brans-Dicke frames.Comment: RevTex 13 pages, 13 figures, a few comments and references adde

A practical approach to determine minimal quantum gate durations using amplitude-bounded quantum controls

We present an iterative scheme to estimate the minimal duration in which a quantum gate can be realized while satisfying hardware constraints on the control pulse amplitudes. The scheme performs multiple numerical optimal control cycles to update the gate duration based on the resulting energy norm of the optimized pulses. We provide multiple numerical examples that each demonstrate fast convergence towards a gate duration that is close to the quantum speed limit, given the control pulse amplitude bound