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Estimating the impact of a treatment on a given response is needed in many biomedical applications. However, methodology is lacking for the case when the response is a continuous temporal curve, treatment covariates suffer extensively from measurement error, and even the exact timing of the treatments is unknown. We introduce a novel method for this challenging scenario. We model personalized treatment-response curves as a combination of parametric response functions, hierarchically sharing information across individuals, and a sparse Gaussian process for the baseline trend. Importantly, our model accounts for errors not only in treatment covariates, but also in treatment timings, a problem arising in practice for example when data on treatments are based on user self-reporting. We validate our model with simulated and real patient data, and show that in a challenging application of estimating the impact of diet on continuous blood glucose measurements, accounting for measurement error significantly improves estimation and prediction accuracy. [ABSTRACT FROM AUTHOR]

We demonstrate RF arbitrary waveform generation based on microwave photonic filtering. We use four-wave mixing in a silicon nanowire to increase the number of taps in an N-tap microwave photonic filter (MPF). Using a programmable optical filter, we can control the tap weights and, hence, the MPF response and corresponding generated waveform. We show uniform and apodized waveforms with four taps and seven taps with tunable central frequencies. [ABSTRACT FROM PUBLISHER]

A fiber-based approach for linear and continuous chirp control in photonics microwave pulse generation is proposed and demonstrated. The technique is based on spectral pulse shaping combined with nonlinear frequency-to-time mapping (FTM). Particularly, the proposed fiber-optics method provides an unprecedented arbitrary chirp-rate control by combining spectral shaping induced by dispersion unbalance in a fiber interferometer, resulting in a nonlinear-chirp frequency interference pattern, with nonlinear FTM. Full linear chirp reconfigurability, including positive, negative and zero chirp rates, is achieved from a single fiber-optics platform by simply varying the relative delay between the interferometer arms. Moreover, a simple balanced photodetection strategy is implemented to achieve dc-free microwave pulses with significantly improved noise figures. High-quality dc-free gigahertz-frequency microwave sinusoids were successfully generated with central frequencies ranging from 100 MHz to 25 GHz and chirp rates ranging from -160 MHz/ns to +160 MHz/ns. [ABSTRACT FROM PUBLISHER]