1462 www.thelancet.com Vol 382 November 2, 2013 Scientifi c inquiry can be guided, and misguided, by past experience. When confronted with the emerging AIDS epidemic in the early 1980s, some scientists and clinicians thought of hepatitis B as a model for how to approach understanding and solving the challenges posed by the burgeoning number of immunodefi ciency cases. Hepatitis B was transmissi...

For the majority of digital watermarking applications, two of the most desirable properties are robustness and imperceptibility. This paper presents a theoretical analysis of watermarking, in which an attacker estimates the watermark with the Wiener lter. A watermark's robustness and imperceptibility can then be expressed in terms of its L2-e ciency|the amount of watermark energy that an attack...

The New York State Energy Research and Development Authority, NYSERDA, seeks to reduce the state’s energy consumption. Among its many activities, the authority supports incentives to purchase high-effi ciency motors. Ultra-high effi ciency, copper-rotor motors (CRMs) have been available for several years, but NYSERDA lacked industrial data on them. The authority therefore initiated an R&D progr...

This paper analyzes the contribution of the socioeconomic and demographic composition of the pool of employed and unemployed individuals to the dynamics of the labor market in diff erent phases of the business cycle. Using individual level data from the Current Population Survey (CPS), we decompose diff erences in employment status transition rates between economic upswings and downturns into c...

This paper estimates the eff ect of informal care provision on female caregiver’s health. We use data from the German Socio-economic Panel and assess eff ects up to seven years after care provision. A simulation-based sensitivity analysis scrutinizes the sensitivity of the results with respect to potential deviations from the conditional independence assumption in the regression adjusted matchi...

We investigate the physical mechanism that decides saturation level of turbulence in collapsing gas clouds. perform a suite high-resolution numerical simulations following collapse turbulent clouds with various effective polytropic exponents $\gamma_{\rm eff}$, initial Mach numbers $\mathcal{M}_0$, and seeds. Equating energy injection rate by gravitational contraction dissipation turbulence, we...

This paper introduces, for an experimental design with design matrix X; the optimal design criterion based on the expectation of the square root of the quadratic form u(XX)u. This provides a geometric and statistical measure of the size of a con ̄dence ellipsoid, namely, the expected radius of an ellipsoid. Properties of the criterion are derived and examples are given to demonstrate the procedu...

We compute the variation of the beaming fraction with the e ciency of high energy -ray production in the outer gap pulsar model of Romani and Yadigaroglu. This allows us to correct the uxes observed for pulsars in the EGRET band and to derive a simple estimate of the variation of e ciency with age. Integration of this model over the population of young neutron stars gives the expected number of...