Non-contact photoacoustic imaging with a silicon photonics-based Laser Doppler Vibrometer.

Photoacoustic imaging has emerged as a powerful, non-invasive modality for various biomedical applications. Conventional photoacoustic systems require contact-based ultrasound detection and expensive, bulky high-power lasers for the excitation. The use of contact-based detectors involves the risk of contamination, which is undesirable for most biomedical applications.

Betaine and feed restriction as potential mitigation strategies against heat stress in two strains of laying hens.

Climate change is increasingly manifesting in temperate regions. Laying hens are highly sensitive to heat stress and mitigation strategies should be implemented to reduce the negative effects. The goal of this experiment was to evaluate the effects of betaine in drinking water (0.

Clinical Validation of Carotid-Femoral Pulse Wave Velocity Measurement Using a Multi-Beam Laser Vibrometer: The CARDIS Study.

Background: Carotid-femoral pulse wave velocity (cfPWV) is the gold standard for noninvasive arterial stiffness assessment, an independent predictor of cardiovascular disease, and a potential parameter to guide therapy. However, cfPWV is not routinely measured in clinical practice due to the unavailability of a low-cost, operator-friendly, and independent device. The current study validated a novel laser Doppler vibrometry (LDV)-based measurement of cfPWV against the reference technique.

On-chip multi-beam frequency shifter through sideband separation.

In this paper, we introduce a novel method to realize a multi-beam optical frequency shifting component for photonic integrated circuits, utilizing an array of parallel optical modulators and a free-propagation region (FPR), such as a slab waveguide-based star coupler. This component generates multiple optical beams with different frequency shifts, making it suitable for various systems, such as multi-beam laser Doppler vibrometry (LDV). We thoroughly elaborate on the working principle of the component through theoretical analysis and demonstrate that by applying periodic wave-like modulation in the modulator array, the discrete harmonic content of the light can be selectively directed to different outputs based on the delay between consecutive modulators.