Cascaded coherent anti-Stokes Raman scattering for high-sensitivity number density determination in the gas phase

Cascaded coherent anti-Stokes Raman scattering (CARS) signals can be efficiently generated from CARS signals when propagating collinearly with the pump/Stokes and probe beams. This effect can be seen as the CARS beam acting as the probe beam and being inelastically scattered a ‘second time’ from the Raman coherence induced along the focus of...

Optical tissue measurements of invasive carcinoma and ductal carcinoma in situ for surgical guidance

Background: Although the incidence of positive resection margins in breast-conserving surgery has decreased, both incomplete resection and unnecessary large resections still occur. This is especially the case in the surgical treatment of ductal carcinoma in situ (DCIS). Diffuse reflectance spectroscopy (DRS), an optical technology based on...

Investigating the fate of natural organic matter at a drinking water treatment plant in south africa using optical spectroscopy and chemometric analysis

The removal dynamics of biodegradable dissolved organic carbon (BDOC) and natural organic matter (NOM) polarity fractions at a water treatment plant (WTP) in South Africa was studied using UV-Vis absorbance, fluorescence excitation-emission matrix, and two-dimensional synchronous fluorescence spectroscopy (SFS). This study gave insights into...

Coherent Raman imaging thermometry with in-situ referencing of the impulsive excitation efficiency

Simultaneous detection of resonant and non-resonant femtosecond/picosecond coherent anti-Stokes Raman spectroscopy (CARS) signals has been developed as a viable technique to provide in-situ referencing of the impulsive excitation efficiency for temperature assessments in flames. In the framework of CARS thermometry, the occurrence of both a...

Microneedles for Optical Spectroscopy: To measure across the skin barrier

[Background] This project provides a proof of principle to use microneedles in combination with optical spectroscopy for bilirubin detection. For newborns, high bilirubin levels in the blood can lead to serious health consequences, such as jaundice, which can lead to brain damage. Therefore, it should be detected as early as possible. However,...