A combined system of gold nanorods and NaGdF 4 :Er 3+ /Yb 3+ upconverting nanoparticles with double functionality, luminescence enhancement, and monitored heating is introduced. The paired nanostructures could become an excellent optical heater with thermal probe incorporated. To study their interaction, the longitudinal surface plasmon resonance of the gold nanorods is tuned to 980 nm, in resonance with the Yb 3+ absorption wavelength, so they can be simultaneously excited. Gold nanorods create a localized electromagnetic fi eld that enhances the emission intensity from upconverting nanoparticles. This luminescence enhancement is shown to depend on the interparticle distance and excitation power and, in this system, reaches a maximum enhancement of 9 for the green emission of Er 3+ ions. At the same time, evidence of strong collective heating from the gold nanorods is demonstrated. The temperature can be controlled by changing the excitation power and measured in situ via the Er 3+ thermally sensitive luminescence. At high excitation powers, the heating can trigger a deformation of the gold nanorods, which limits the maximum temperature achievable in the system to 160 °C. Combining these nanostructures provides an all-optical heating system with improved emission intensity that can monitor the temperature achieved.

Upconverting nanoparticles (UCNPs) are well-known for their capacity to convert near-infrared light into UV/visible light, benefitting various applications where light triggering is required. At the nanoscale, loss of luminescence intensity...

A seismocardiography based methodology is introduced for predicting the start and the end of diastole to be used in diastolic timed vibrations. An accelerometer was placed on the sternum of 142 participants (120 healthy and 22 ischemic heart patients) to record Seismocardiogram (SCG). It is claimed that SCG, in combination with electrocardiogram (ECG), provides a mechanism for predicting diastole. It is demonstrated that prediction of the aortic valve closure point in the SCG signal helps start the vibrator in time to cover most of the isovolumic relaxation period. Also, through prediction of the mitral valve closure point, safety of the technique can be assessed by estimation of the amount of unwanted vibrations applied during the isovolumic contraction period.

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