A novel straightforward, accessible and efficient approach is presented for performing hyperspectral time-domain diffuse optical spectroscopy to determine the optical properties of samples accurately using geometry specific models. To allow bulk parameter recovery from measured spectra, a set of libraries based on a numerical model of the domain being investigated is developed as opposed to the conventional approach of using an analytical semi-infinite slab approximation, which is known and shown to introduce boundary effects. Results demonstrate that the method improves the accuracy of derived spectrally varying optical properties over the use of the semi-infinite approximation.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5030049 | PMC |
http://dx.doi.org/10.1364/BOE.7.003784 | DOI Listing |
Nano Lett
January 2025
University Paris-Saclay, CNRS, Laboratoire de Physique des Solides, Orsay 91405, France.
Thermal transport in nanostructures plays a critical role in modern technologies. As devices shrink, techniques that can measure thermal properties at nanometer and nanosecond scales are increasingly needed to capture transient, out-of-equilibrium phenomena. We present a novel pump-probe photon-electron method within a scanning transmission electron microscope (STEM) to map temperature dynamics with unprecedented spatial and temporal resolutions.
View Article and Find Full Text PDFEcancermedicalscience
November 2024
National Centre for Radiotherapy, Oncology and Nuclear Medicine, Korle Bu Teaching Hospital, Accra, Ghana.
Optic nerve gliomas (ONG) are benign central nervous system tumours and the most common tumours of the optic nerve in children, often occurring before age 20. These tumours are slow-growing and can be treated with surgery and/or radiation therapy. Surgical resection is, however, associated with significant morbidity and loss of vision in the affected eye.
View Article and Find Full Text PDFHeliyon
July 2024
D-Eye Srl, Padova, 35131, Italy.
Widespread screening is crucial for the early diagnosis and treatment of glaucoma, the leading cause of visual impairment and blindness. The development of portable technologies, such as smartphone-based ophthalmoscopes, able to image the optical nerve head, represents a resource for large-scale glaucoma screening. Indeed, they consist of an optical device attached to a common smartphone, making the overall device cheap and easy to use.
View Article and Find Full Text PDFBiomed Opt Express
January 2025
Biophotonics@Tyndall, IPIC, Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland.
Cardiovascular imaging with camera-on-tip endoscopes has the potential to provide physiologically relevant data on the tissue state and device placement that can improve clinical outcomes. In this work, we review the unmet clinical need for image-based cardiovascular diagnostics and guidance for minimally invasive procedures. We present a 7 Fr camera-on-tip endoscope with fibre-coupled multispectral illumination that includes methods for imaging in a blood-filled field of view (FOV).
View Article and Find Full Text PDFJ Biol Chem
January 2025
Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, MD 21205 USA. Electronic address:
Kinase translocation reporters (KTRs) are powerful tools for single-cell measurement of time-integrated kinase activity but suffer from restricted dynamic range and limited sensitivity, particularly in neurons. To address these limitations, we developed enhanced KTRs (eKTRs) for protein kinase A (PKA) and extracellular signal-regulated kinase (ERK) by (i) increasing KTR size, which reduces the confounding effect of KTR diffusion through the nuclear pore, and (ii) modulating the strength of the bipartite nuclear localization signal (bNLS) in their kinase sensor domains, to ensures that the relative distribution of the KTR between the nucleus and cytoplasmic is determined by active nuclear import, active nuclear export, and relative activity of their cognate kinase. The resultant sets of ePKA-KTRs and eERK-KTRs display high sensitivity, broad dynamic range, and cell type-specific tuning.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!