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International audienceIn the last decade, high-intensity pulsed electric fields with nanosecond durations (3-300 ns) have found breakthrough biomedical applications, e.g., in cancer treatment and gene therapy; however, the physical mechanisms underlying the interaction between nanosecond pulsed electric fields (nsPEFs) and cells, tissues, or organs are not yet fully elucidated. The precise knowledge of the electromagnetic dose received by the exposed sample at the macroscopic, and better still at the microscopic scale, is essential to complete our understanding of the phenomena involved and for adequate interpretation and reproducibility of the results. In this paper, we report a dosimetric and microdosimetric study of an in vitro exposure setup based on a transverse electromagnetic (TEM) cell that allows the exposure of cells in a Petri dish to nsPEFs. The rectangular and bipolar pulses delivered to the cells had a total duration of 1.2 ns and an amplitude of 2 kV. The electric field in situ was characterized experimentally with a nonmetallic probe and numerically using a finite-difference time-domain algorithm. Results of real-time monitoring of temperature were obtained at the subcellular level by using microfluorimetry, which is a method of imaging temperature by using a fluorescent molecular probe with thermosensitive properties

The work presented in this paper deals with the performance analysis of the whole 3D reconstruction process of imaged objects, specifically of the set of geometric primitives describing their outline and extracted from a pair of images knowing their associated camera models. The proposed analysis focuses on error estimation for the edge detection process, the starting step for the whole reconstruction procedure. The fitting parameters describing the geometric features composing the workpiece to be evaluated are used as quality measures to determine error bounds and finally to estimate the edge detection errors. These error estimates are then propagated up to the final 3D reconstruction step. The suggested error analysis procedure for stereovision-based reconstruction tasks further allows evaluating the quality of the 3D reconstruction. The resulting final error estimates enable lastly to state if the reconstruction results fulfill a priori defined criteria, for example, fulfill dimensional constraints including tolerance information, for vision-based quality control applications for example.

High-voltage (HV) ultrashort pulse technologies have found many applications in areas such as medicine, biology, food processing, environmental science and defense. Some applications are dependent on the pulse parameters such as duration, amplitude, shape, as well as the number of pulses applied and the frequency rate. Generators that can produce powerful electrical pulses with adjustable duration, amplitude and shape are convenient but still unusual. In this paper, we present and characterize a robust and versatile generator built on the frozen wave generator concept using photoconductive semiconductor switches. The results show that the generator can produce pulses of various shapes, peak-to-peak amplitudes up to 13.1 kV, maximum amplitudes of 6.9 kV and with durations in the nanosecond and subnanosecond range. Intense subnanosecond pulses have recently gained attention due to their potential ability to reach cells interior.Index Terms -High voltage, optoelectronic switching, versatile nanosecond and subnanosecond pulse generation, pulse shaping, biomedical applications.