Correlation mapping optical coherence tomography (cmOCT) is a recently proposed technique that extends the capabilities of OCT to enable mapping of vasculature networks. The technique is achieved as a processing step on OCT intensity images that does not require any modification to existing OCT hardware. In this paper we apply the cmOCT processing technique to in vivo human imaging of the volar forearm. We illustrate that cmOCT can produce maps of the microcirculation that clearly follow the accepted anatomical structure. We demonstrate that the technique can extract parameters such as capillary density and vessel diameter. These parameters are key clinical markers for the early changes associated with microvascular diseases. Overall the presented results show that cmOCT is a powerful new tool that generates microcirculation maps in a safe non-invasive, non-contact technique which has clear clinical applications.

Standard optical coherence tomography (OCT) in combination with software tools can be harnessed to generate vascular maps in vivo. In this study we have successfully combined a software algorithm based on correlation statistic to reveal microcirculation morphology on OCT intensity images of a mouse brain in vivo captured trans-cranially and through a cranial window. We were able to estimate vessel geometry at bifurcation as well as along vessel segments down-to mean diameters of about 24 μm. Our technique has potential applications in cardiovascular-related parameter measurements such as volumetric flow as well as in assessing vascular density of normal and diseased tissue.

Current-generation smartphones boast a video unit comprising a camera next to a white light emitting diode and this configuration would be suitable for reflection-mode bio-optical sensing and imaging applications. We demonstrate reflection photoplethysmographic (PPG) imaging using this technology on the index finger of a male volunteer during rest and immediately after performing a short run. The returned signals carry useful PPG signals and were used, for example, to compute change in heart rate. Our results are encouraging, especially in the area of personal and home-based care applications.

The use of microneedles as a method of circumventing the barrier properties of the stratum corneum is receiving much attention. Although skin disruption technologies and subsequent transdermal diffusion rates are being extensively studied, no accurate data on depth and closure kinetics of microneedle-induced skin pores are available, primarily due to the cumbersome techniques currently required for skin analysis. We report on the first use of optical coherence tomography technology to image microneedle penetration in real time and in vivo. We show that optical coherence tomography (OCT) can be used to painlessly measure stratum corneum and epidermis thickness, as well as microneedle penetration depth after microneedle insertion. Since OCT is a real-time, in-vivo, nondestructive technique, we also analyze skin healing characteristics and present quantitative data on micropore closure rate. Two locations (the volar forearm and dorsal aspect of the fingertip) have been assessed as suitable candidates for microneedle administration. The results illustrate the applicability of OCT analysis as a tool for microneedle-related skin characterization.

We present study results on visible light reflection photoplethysmographic (PPG) imaging with a mobile cellular phone operated in video imaging mode. PPG signal components around 0.1 Hz attributed to the sympathetic component of the heart rate, 1 Hz as the heart rate and 2 Hz as heart rate high order harmonic were quantified on the index finger of a healthy volunteer. The green channel reported PPG signals throughout the sampled area. The blue and red channel returned plethysmographic information, but the signal strength was highly position specific. Our results obtained with a cellular phone as the data acquisition device are encouraging, especially in the broad context of personal or home-based care and the role of cellular phone technology in medical imaging.

The use of algae as a feedstock for biofuels production has drawn considerable attention due to their high biomass yield, their ability to be cultivated using degraded water on nonarable land, and their ability to recover nutrients from wastewater. Although algae have the potential to provide biomass for biofuels, some challenges remain and the limitations may be overcome by improving algal growth rates together with lipid synthesis. To achieve this, scientific researchers have focused on isolating and screening algal strains with better growth rates and lipid synthesis capabilities, bioengineering, and optimizing culture systems. The present review focuses on the biophotonic-based manipulations that can be applied to optimize solar-powered photobioreactors (PBRs).Hence, three different types of solar filters are reviewed herein, that is, the colored glass, thin-film, and thermochromic filters. This review provides evidence that bright red-colored glass filters can lower the spectral intensity of solar radiation from 1982.13 to 393.71 μmol m −2 s −1 , which is preferable for improved biomass productivity. Changing filter color, once the desired biomass concentration has been amassed, to medium blue or bright pink further improves lipid yield. A 34% improvement in biomass productivity was observed for Chlorella vulgaris cultured under thin-film filters. Thin-film filters are also effective in regulating PBR temperature within the 24-31 C range, which is tolerable for most algal species. Furthermore, this study highlights that the applicability of thermochromic filters in PBR designs is still yet to be investigated. Thermochromic filters are reflective and absorptive under high and low temperatures, respectively, a technology that can be a solution to the overheating challenge of PBRs. This review recommends the coupling of these light

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