Bio-optical model

The diffuse attenuation coefficient (K ) is one of several apparent optical properties (AOPs) of natural waters described by Preisendorfer [25]. Unlike inherent optical properties (lOPs) described below, AOP s depend on the quality of incident light as well as the optical qualities of the water. In spite of this apparent limitation (and in part because the differences between AOP s and lOP s were said to be small in many instances [26]), a case was argued for the standard use of to characterize natural waters for purposes of optical comparisons and bio-optical models [27,28]. Gordon [17,29] provided a practical means to adjust measurements to remove much of its dependence on the ambient light field. In particular, Gordon [17] established that, after adjustment (described below), averaged from surface to Zio% is proportional to the summed concentrations of constituent optical compounds. 

Constituents controlling UV attenuation in natural waters bio-optical models... 

Bio-optical models have been developed to predict spectral attenuation as a function of conveniently measured parameters and are discussed extensively in Mobley [5] and Kirk [6]. Since the pioneering work of Smith and Baker [42], bio-optical models typically break down diffuse attenuation into optical constituents of natural waters. In an approach covering UV-B and UV-A wavelengths summarized by Baker and Smith [9,43], these components are represented as partial attenuation coefficients (A for each term not shown for simplicity) ... 

A linear model for scaling Rd DOC,320 to DOC concentration was adopted by Baker and Smith [43], who used a constant value of R d DOc,320= 1-3 in their bio-optical model but cited a range of values from as low as K doc,320 = 0-75 for... 

K.S. Baker, R.C. Smith (1982). Bio-optical classification and model of natural waters. 

However, as pointed out by Sathyendranath and Platt (1994) and Sathyen-dranath etal. (1999), models that only consider mixed layer dynamics without taking into account changes in bio-optical properties of phytoplankton are probably insufficient to explain the occurrence of phytoplankton blooms in the Arabian Sea. Sathyendranath etal. (1999) provided evidence for significant seasonal changes in the parameters that describe the dependence of photosynthesis rate of phytoplankton on the amount of light available (P-I curves), viz. the assimilation number (PmB) and the initial slope of photosynthesis-light curve (aB), as well as in the specific absorption coefficient of phytoplankton (ac ). 

Certainly biomolecular NMR is not the single method which is important for hit identification in pharmaceutical research. It is always a combination of techniques and a team effort that leads to a successful drug. This can involve biologists (basic understanding, assay development, bio-informatics), chemists (both bench chemists and modelers), screening specialists (HTS/natural products) and spectroscopists (X-ray, optical methods, surface plasmon resonance, NMR). 

G. Vishnoi, A. H. Hielscher, N. Ramanujam, and B. Chance, Photon Migration Through Fetal Head in Utero Using Continuous Wave, Near-Infrared Spectroscopy Development and Evaluation of Experimental and Numerical Models, J. Bio-med. Optics, 5(2), 163-172 (2000). 

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