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Fiber-coupled luminescence dosimetry with inorganic crystals
Published in Sam Beddar, Luc Beaulieu, Scintillation Dosimetry, 2018
Si-doped gallium nitride (GaN) emits RL with a high-light yield, and because it also has a high density and a high atomic number, it is possible to design detectors of a very small volume GaN coupled to silica fiber has been studied in the context of external beam radiotherapy, brachytherapy, and interventional radiology [25]. The RL emission from GaN is centered in a relatively narrow band around , which offers possibilities for chromatic stem removal similar to the technique developed by Veronese et al. [39] for Eu-doped silica fibers.
III-Nitrides–Based Biosensing
Published in Iniewski Krzysztof, Integrated Microsystems, 2017
Manijeh Razeghi, Ryan McClintock
The nitrides of group-III metal elements or “III-nitrides” are commonly referred to as aluminum nitride (AlN), gallium nitride (GaN), indium nitride (InN), and their alloys, all of which are compounds of nitrogen—the smallest group V element in the Periodic Table and an element with one of the highest values of electronegativity. The III-nitride material system exhibits a direct band-gap energy that can be continuously tuned from 0.7 eV all the way to 6.2 eV, which corresponds to a wavelength range from 1.78 μm to 200 nm. This makes it ideally suited toward the realization of sources and detectors for UV florescence-based biodetection.
Evaluating the blue-light hazard from solid state lighting
Published in International Journal of Occupational Safety and Ergonomics, 2019
John D. Bullough, Andrew Bierman, Mark S. Rea
The introduction of solid state lighting using light-emitting diode (LED) technology has ignited widespread interest in the ways that lighting can offer benefits to people [1], including on-axis vision [2], improved peripheral visibility at night [3–5], enhanced perceptions of brightness and security [6–9] and spectral tuning for management of circadian rhythms [10–14]. Yet, as illustrated in a recent report from the American Medical Association (AMA) [15], indium gallium nitride (InGaN) LEDs are also bringing about new questions and reviving older concerns about unwanted impacts of these light sources, such as light pollution [16–19], discomfort glare [20–26], circadian disruption [27–29] and retinal damage via a mechanism known as the blue-light hazard [30–33]. The blue-light hazard, the topic of the present article, is of particular concern because this type of retinal damage is often irreversible, although recovery has been exhibited in mild cases [33].
Conventional intensive versus LED intensive phototherapy oxidative stress burden in neonatal hyperbilirubinaemia of haemolytic origin
Published in Paediatrics and International Child Health, 2020
Wesam A. Mokhtar, Laila M. Sherief, Hany Elsayed, Mohamed M. Shehab, Sherief M. El Gebaly, Atef M. M. Khalil, Mohamed Sobhy, Naglaa M. Kamal
Several phototherapy devices using light sources of different wavelengths and intensities are available. Fluorescent tubes and halogen spotlights are the most commonly used light sources [6,7]. Intensive conventional phototherapy, defined by the American Academy of Pediatrics (AAP) as irradiation of at least 30uW/cm2/nm in the 430–490 nm band or higher, is one of the phototherapy modalities that can rapidly decrease total serum bilirubin (TSB) below the threshold of exchange transfusion [8]. High-intensity gallium nitride light-emitting diode (LED) phototherapy generates higher light irradiance levels than conventional phototherapy [9].