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Examining diagenetic parameters such as the organic carbonate contents and the crystallinity of bone apatite quantify the post-mortem alteration of bone. Burial conditions are one of the factors that can influence the diagenesis process. We studied the changes to the organic and mineral components and crystallinity of human bone remains from five Medieval sites in Turkey: Hakemi Use, Komana, İznik, Oluz Höyük and Tasmasor using Attenuated Total Reflectance Fourier Transform Infrared spectroscopy (ATR-FTIR) and principal component analysis (PCA). Analysis of spectral band ratios related to organic and mineral components of bone demonstrated differences in the molecular content in the skeletal remains from the five sites. In order to examine the degree of carbonation of a phosphate matrix, curve-fitting procedures were applied to the carbonate band. We found that the infrared crystallinity index appears to not be sensitive to carbonate content at room temperature for the bone remains studied here. The recrystallization process in bone remains behaved differently among the archaeological sites. The results demonstrate that the burial environments differently affect the organic and mineral components of archaeological bone remains., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Boletus griseus and Boletus edulis are two well-known wild-grown edible mushrooms which have high nutrition, delicious flavor and high economic value distributing in Yunnan Province. In this study, a rapid method using Fourier transform infrared (FT-IR) and ultraviolet (UV) spectroscopies coupled with data fusion was established for the discrimination of Boletus mushrooms from seven different geographical origins with pattern recognition method. Initially, the spectra of 332 mushroom samples obtained from the two spectroscopic techniques were analyzed individually and then the classification performance based on data fusion strategy was investigated. Meanwhile, the latent variables (LVs) of FT-IR and UV spectra were extracted by partial least square discriminant analysis (PLS-DA) and two datasets were concatenated into a new matrix for data fusion. Then, the fusion matrix was further analyzed by support vector machine (SVM). Compared with single spectroscopic technique, data fusion strategy can improve the classification performance effectively. In particular, the accuracy of correct classification of SVM model in training and test sets were 99.10% and 100.00%, respectively. The results demonstrated that data fusion of FT-IR and UV spectra can provide higher synergic effect for the discrimination of different geographical origins of Boletus mushrooms, which may be benefit for further authentication and quality assessment of edible mushrooms., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Nucleic acid & serology based methods have revolutionized plant disease detection, however, they are not very reliable at asymptomatic stage, especially in case of pathogen with systemic infection, in addition, they need at least 1-2days for sample harvesting, processing, and analysis. In this study, two reflectance spectroscopies i.e. Near Infrared reflectance spectroscopy (NIR) and Fourier-Transform-Infrared spectroscopy with Attenuated Total Reflection (FT-IR, ATR) coupled with multivariate exploratory methods like Principle Component Analysis (PCA) and Partial least square discriminant analysis (PLS-DA) have been deployed to detect begomovirus infection in papaya leaves. The application of those techniques demonstrates that they are very useful for robust in vivo detection of plant begomovirus infection. These methods are simple, sensitive, reproducible, precise, and do not require any lengthy samples preparation procedures., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The effect of pH on the structure of methanol was investigated by FT-NIR (Fourier transform near-infrared) spectroscopy and generalized two-dimensional (2D) correlation spectroscopy. pH perturbed 2D correlation spectra are calculated for the spectra in the 5,500-4,000, 7,500-5,500 cm(-1) regions at different pH values. We observed that the stretching of CH(3) was shifted because of the direct interaction of the CH(3) group of methanol with the OH group of water, the change of free OH is more sensitive to pH than the cyclic dimmer and CH.O.

We present a general method for curve-fitting Fourier manipulated spectra, comprising apodized, smoothed, derivatised and deconvoluted spectra. The analytical expressions of Fourier manipulated bands in the spectral domain, needed for the curve-fitting, are usually very complex or do not even exist; hence an accurate curve-fit of Fourier manipulated spectra becomes unfeasible. Our strategy is to construct both the model and their derivatives in the Fourier domain, where they have simple and general expressions, and then Fourier transform them back to the spectral domain. The first benefit of this approach is the accurate curve-fitting of Fourier deconvoluted spectra, a main step in the secondary structure estimation of proteins by FTIR spectroscopy.

The nonlinear fitting method, based on the ordinary least squares approach, is one of several methods that have been applied to fit experimental data into well-known profiles and to estimate their spectral parameters. Besides linearization measurement errors, the main drawback of this approach is the high variance of the spectral parameters to be estimated. This is due to the overlapping of individual components, which leads to ambiguous fitting. In this paper, we propose a simple mathematical tool in terms of a fractional derivative (FD) to determine the overlapping band spectral parameters. This is possible because of several positive effects of FD connected with the behavior of its zero-crossing and maximal amplitude. For acquiring a stable and unbiased FD estimate, we utilize the statistical regularization method and the regularized iterative algorithm when a priori constraints on a sought derivative are available. Along with the well-known distributions such as Lorentzian, Gaussian and their linear combinations, the Tsallis distribution is used as a model to correctly assign overlapping bands. To demonstrate the power of the method, we estimate unresolved band spectral parameters of synthetic and experimental infra-red spectra.