We report new modeling and error reduction methods for differential-absorption optical-depth (DAOD) measurements of atmospheric constituents using direct-detection integrated-path differential-absorption lidars. Errors from laser frequency noise are quantified in terms of the line center fluctuation and spectral line shape of the laser pulses, revealing relationships verified experimentally. A ...

Our knowledge of how the body absorbs iron from the diet and how this process is controlled has increased at a rapid rate in recent years. The identification of key molecules, including the iron regulatory peptide hepcidin, and the analysis of how they are regulated and interact have led to the development of an integrated model for the control of iron absorption by body iron requirements. Rese...

We report the first (to our knowledge) experimental observation of resonant cavity-enhanced photosensitivity in As(2)S(3) chalcogenide glass film at 1550 nm telecommunication wavelength. The measured photosensitivity threshold is <0.1 GW/cm(2), and a photoinduced refractive index increase as large as 0.016 is observed. The photosensitive process is athermal; further, we confirm the absence of t...

We propose a novel multispectral reconstruction-classification method for simultaneously recovering absorption and scattering coefficients from images of absorbed optical energy. In contrast with pre-existing chromophore reconstruction methods, this approach does not require prior knowledge of the characteristic spectra of the absorbers, which is not always available. Numerical experiments perf...

Phenylhydrazine is oxidized stoichiometrically by two equivalents of ferricyanide to produce phenyldiimide and ferrocyanide. This reaction permits accurate determination of the absorption maxima and molar absorption coefficients of phenyldiimide in aqueous solution. These values are identical or extremely similar to those of phenyldiimide produced by decarboxylation of phenylazoformic acid. Kno...

Measurements of the cosmic-ray air-shower fluorescence at extreme energies require precise knowledge of atmospheric conditions. The absolute calibration of the cosmic-ray energy depends on the absorption of fluorescence light between its origin and point of its detection. To reconstruct basic atmospheric parameters we review a novel analysis method based on twoand multi-angle measurements perfo...

Six transition metal-salen complexes (metal = Fe, Mn and Cr) 1-6 have been synthesized and characterized using different spectroscopic and electrochemical techniques. The binding studies of natural antioxidant, curcumin with the complexes (1-6) have been carried out by electronic absorption spectroscopic technique. The substantial shift in the absorption maximum of complexes (1-6) when they bin...

We present a novel method for testing drug permeability that features human cells cultured on hydrogel scaffolds made to accurately replicate the shape and size of human small intestinal villi. We compared villous scaffolds to more conventional 2D cultures in paracellular drug absorption and cell growth experiments. Our results suggest that 3D villous platforms facilitate cellular differentiati...

Urinary oxalate is mostly derived from the absorption of ingested oxalate and endogenous synthesis. The breakdown of vitamin C may also contribute small amounts to the urinary oxalate pool. The amount of oxalate absorbed is influenced by the oxalate content of the diet, the concentrations of divalent cations in the gut, the presence of oxalate-degrading organisms, transport characteristics of t...

Knowledge of the impact of potential sources of error in spatial frequency domain imaging (SFDI) is essential for the quantitative characterization of absorption and scattering in tissue and other turbid media. We theoretically investigate the error in the derived absorption and scattering parameter, subject to typical experimental and theoretical sources of errors. This provides a guideline to...