Journal of Chemometrics

Cover image for Vol. 28 Issue 2

February 2014

Volume 28, Issue 2

Pages i–iii, 71–136

  1. Issue Information

    1. Top of page
    2. Issue Information
    3. Research Articles
    1. Issue Information (pages i–iii)

      Version of Record online: 6 FEB 2014 | DOI: 10.1002/cem.2538

  2. Research Articles

    1. Top of page
    2. Issue Information
    3. Research Articles
    1. You have full text access to this OnlineOpen article
      Automated resolution of overlapping peaks in chromatographic data (pages 71–82)

      Lea G. Johnsen, José Manuel Amigo, Thomas Skov and Rasmus Bro

      Version of Record online: 16 DEC 2013 | DOI: 10.1002/cem.2575

      A new approach for automatically modeling GC-MS data using PARAFAC2 has been developed. Automating the modeling enables both the inexperienced and trained users to perform comprehensive and advanced analysis of chromatographic data with a minimum of manual labor.

    2. You have free access to this content
      Determination of rice type by 1H NMR spectroscopy in combination with different chemometric tools (pages 83–92)

      Yulia B. Monakhova, Douglas N. Rutledge, Andreas Roßmann, Hans-Ulrich Waiblinger, Manuela Mahler, Maren Ilse, Thomas Kuballa and Dirk W. Lachenmeier

      Version of Record online: 8 DEC 2013 | DOI: 10.1002/cem.2576

      A 400-MHz 1H nuclear magnetic resonance (NMR) spectroscopy and multivariate data analysis were used in the context of food surveillance to discriminate 46 authentic rice samples according to type. For the first time, the chemometric method independent component analysis (ICA) was applied to differentiate clusters of rice from the same type (Basmati, non-Basmati long-grain rice, and round-grain rice) and, to a certain extent, their geographical origin. Among the classification methods, partial least squares discriminant analysis and ICA gave the best values of specificity and sensitivity (above 0.94).

    3. Chemometrics study of the kinetics of the Griess reaction (pages 93–99)

      Masoud Shariati-Rad, Mohsen Irandoust and Maryam Haghighi

      Version of Record online: 5 DEC 2013 | DOI: 10.1002/cem.2577

      The kinetics of the Griess reaction between nitrite, 3-nitroaniline and 1-naphtylamine was explored by chemometrics methods. The concentrations of the reactants were such that a second-order kinetic reaction took place. Data explorations based on principal component analysis and multivariate curve resolution-alternating least squares were performed to obtain information about the reaction. The results of the data analysis showed that the kinetic reaction proceeds through a two-step mechanism. Data analysis approaches based on hard modeling and global hard modeling were used.

    4. Performance evaluation of CAESAR–QSAR output using PAHs as a case study (pages 100–107)

      Marjan Vračko and Sol Bobst

      Version of Record online: 5 DEC 2013 | DOI: 10.1002/cem.2578

      The set of 16 polycyclic aromatic hydrocarbon compounds was examined with the Internet available quantitative structure–activity relationship (QSAR) CAESAR models. For mutagenicity, carcinogenicity, developmental toxicity, and skin sensitization, the report includes the predicted classifications, the analysis of applicability domains, and the similarity sets, which consist of the similar compounds from the training sets. These results were further analyzed with chemometrical methods, that is, hierarchical clustering, principal component analysis, and self-organizing maps, which were used for clustering and to define the cluster indicators. Such analysis assists the users in planning the application of QSAR models for hazard communication in regulatory compliance and in research of new active compounds.

    5. Ligand-based design, virtual screening, and ADME/T-based profiling on a dataset of 1,3,5-triazine-substituted benzene sulfonamides as carbonic anhydrase inhibitors (pages 108–115)

      Amrita K. Saluja, Meena Tiwari and Surendra Kumar

      Version of Record online: 9 DEC 2013 | DOI: 10.1002/cem.2579

      A series of 1,3,5-triaizne-substituted benzene sulfonamides as carbonic anhydrase inhibitors were subjected to QSAR analysis and virtual screening on ZINC database. ADME/T analysis was performed on the hits (seven compounds) obtained by virtual screening. The hits obtained showed good predicted activity against CAII and CAIX isozymes comparable with standard drugs acetazolamide and methazolamide.

    6. Support vector regression with digital band pass filtering for the quantitative analysis of near-infrared spectra (pages 116–122)

      Bilal Malik, Krishna Chaitanya and Mohammed Benaissa

      Version of Record online: 15 DEC 2013 | DOI: 10.1002/cem.2580

      A novel calibration technique using support vector regression coupled with band pass filter for determination of glucose concentration from near-infrared spectra of mixtures composed of glucose, urea and triacetin is proposed in this paper. The results show that the standard error of prediction decreases to 15.17 mg/dL when combining Gaussian band pass filter and decreases to 14.59 mg/dL when using a Chebyshev band pass filter coupled with support vector machine for regression in comparison to 42 mg/dL without pre-processing.

    7. Enhanced genetic operators design for waveband selection in multivariate calibration based on NIR spectroscopy (pages 123–136)

      Carlos Cernuda, Edwin Lughofer, Peter Hintenaus and Wolfgang Märzinger

      Version of Record online: 7 JAN 2014 | DOI: 10.1002/cem.2583

      Current data acquisition techniques provide huge amounts of data making dimensionality reduction desirable. Genetic algorithms allow selecting which variables contain the most relevant information to represent all the original ones. Traditional genetic operators seem to be too general, leading to results that could be improved by employing available problem-specific information. In near-infrared calibration, wavebands allow a more robust model design. We design three crossover operators, which promote wavebands selection, achieve better-quality solutions, and converge faster and smoother than state-of-the-art operators.