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Chemometrics & Informatics

The use of transmission Raman spectroscopy for quantitative assessment of pharmaceutical tablets using different multivariate approaches was investigated. Although Raman spectroscopy is most often used in backscatter geometry, in this paper a transmission approach was utilized, where the Raman scattered light is detected at the back side of the tablets.

Simplifying analytical methods for identifying illicit drugs of abuse would be a boon to forensic scientists and law enforcement agencies. Cheminformatics shows how chromatography coupled to mass spectrometry might be improved to accelerate the process.

One of the most frequent forms of contamination present in water systems is related to oil spills coming from urban or industrial areas, as well as accidental spills from tanker ships. For the control and screening of such contamination, it is necessary to use analytical processes with proper detection and accuracy limits, which at the same time must be simple and quick.

A glucose sensor based on a room-temperature ionic liquid rather than conventional solvents has much better acid-resistance than other sensors and so could be developed into a much more robust sensor device for diabetes monitoring.

Laser-induced breakdown spectroscopy (LIBS) coupled with non-parametric permutation based hypothesis testing is demonstrated to have good performance in discriminating float glass samples. Without rigid distributional assumptions, the permutation test exhibits excellent discriminating power while holding the actual size of Type I error at the nominal level.

New drugs that block kinase enzymes irreversibly could be used in cancer therapy as well as in studying how this class of enzymes functions. An informatics analysied has allowed molecular editing to produce novel leads.

Random projection (RP) is a linear method for the projection of high-dimensional data onto a lower dimensional space. RP uses projection vectors (loading vectors) that consist of random numbers taken from a symmetric distribution with zero mean. The basic ideas of RP are presented, and tested with artificial data and data from chemoinformatics and chemometrics.

A statistical analysis of visible and near-infrared (vis-NIR) spectroscopy has demonstrated the feasibility of quantifying oil, protein and total glucosinolate content of three cultivars of rapeseed.

An extended tolerance interval model for the shelf life estimation of pharmaceutical products is presented assuming two distinct influence sources, namely the tablet-to-tablet variability and the analytical measurement error. Another novel and important approach in the paper is that the tolerance interval is constructed for the true (and not for the measured) assay content.

Multivariate analysis of atomic absorption spectroscopic data is helping scientists home in on the problem of decreased fruit and vegetable consumption being associated with an elevated concentration of cadmium in the blood of male smokers.

The ability of five sample selection methods for local chemometrics and three variable selection algorithms were compared for the development and the transfer of whole soybeans protein and oil near infrared prediction models. Two new methods based on a similarity index considering Euclidian distance among Fourier coefficients were introduced and tested against more common approaches (locally weighted regression, LOCAL).

Metabolic fingerprinting has been shown to be a powerful tool for exploring Biomarkers in a range of disorders and the pathophysiological mechanisms of disease. A new study has now applied the technique to childhood obesity to intriguing effect.

In this study five Sri Lanka black teas were analyzed by electronic nose, electronic tongue and sensory panel. Data were analyzed with principle component analysis (PCA), linear discriminant analysis (LDA) and in case of sensory analysis with one-way ANOVA. The partial least square regression (PLS) was used to estimate the sensory attributes.

Chemometrics and mass spectrometry can be used to classify wine according to geographic region. Proof of principle was undertaken with the new electronic nose carried out successfully with Tempranillo wines from Spain and Australia.

The authors introduce two concepts to develop a method, where a proper change of rows and columns of a data matrix yields patterns of significant new information. By using their diagonal matrix measure and local distance matrix the similar objects were arranged close to each other in the data matrix and simultaneously the variables responsible for their similarity were collected close to the diagonal part defined by these objects.

The rules that dictate the three-dimensional shapes of RNA molecules are primarily based not on complex chemical interactions but simply on geometry, according to a new biophysical study. The findings circumvents the fact that NMR spectroscopy and X-ray crystallography are not always effective tools in the analysis of complex biomolecules with potentially myriad conformations.

This paper introduces a top-down hierarchical clustering approach called PLS-Tree. The PLS-Tree uses the scores of PLS regression models as the basis for splitting clusters. The approach is illustrated using two QSAR examples and one dataset based on hyperspectral images of liver tissue.

A statistical analysis of experimental data on laboratory animals shows that the resin of the middle-eastern tree Commiphora, better known as "myrrh" can act as a protective antioxidant against liver damage caused by organic lead compounds.

This paper presents a method of searching, identifying and crossreferencing metal alloys based on their chemical composition and/or mechanical properties, typically obtained by analysis and tests. The method uses a pattern similar to the approach of a human expert, a classification of metals based on metallurgical expertise and fuzzy logic for identifying metals and comparing their chemical and mechanical properties.

Material degradomics borrows the informatics ethic from molecular biology and biochemistry and applies it to historical artefacts, in particular old books. Degradomics could allow conservationists to profile the complete gamut of volatile organic compounds released by artefacts and so tailor their efforts to improving stability or halting damage.