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Simultaneous component analysis as an interesting preliminary data analysis method in GC-MS – An example of headspace screening of Polish grasses

Wróbel-Szkolak Joanna, Cwener Anna, Pietraś Rafał, Komsta Łukasz

Acta Chromatographica

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2024

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Vol. 36, no. 1

52--58

EN

70 species of grasses family (Poaceae), coming from genera: Agrostis, Alopecurus, Anthoxanthum, Apera, Arrhenatherum, Avena, Brachypodium, Briza, Bromus, Calamagrostis, Corynephorus, Cynosurus, Dactylis, Danthonia, Deschampsia, Digitaria, Echinochloa, Elymus, Eragrostis, Festuca, Glyceria, Helictotrichon, Hierochloe, Holcus, Hordeum, Koeleria, Leymus, Lolium, Milium, Molinia, Nardus, Panicum, Phalaris, Phleum, Phragmites, Poa, Saccharum and Setaria, collected mostly from natural stands in Poland during 2020 season, were subjected to GC-MS fingerprinting of headspace volatile fraction above dried material. Obtained mass spectrometry data were analyzed by means of principal component analysis (PCA) and hierarchical cluster analysis (HCA). Five species: Glyceria maxima (Hartm.) Holmb., Lolium multiflorum Lam., Hordeum jubatum L., Bromus tectorum L. and Bromus secalinus L. were identified as outliers, which is consistent with our earlier analysis by thin layer chromatography. These species deserve further look and their outliance is orthogonal to coumarin content, which was independently observed for odorant species of grasses.

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Use a Modified Ring Method to Predict Drape Properties in Drapery Fabrics

Carrera-Gallissà E., Capdevila X., Valldeperas J.

Autex Research Journal

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2018

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Vol. 18, no. 2

143--148

EN

Seven drape indicators and four of the parameters assessed in the UPC ring test were determined by using canonical correlations in 15 commercial drapery fabrics of variable composition, aerial weight and weave type. A regression equation relating drape ratio (%DR) and parameter h in the ring test was thus established. Based on the results, the ring test provides a useful tool for the routine industrial assessment of drape in finished drapery fabrics without the need for additional equipment to determine the drape.

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Statistical downscaling of probability density function of daily precipitation on the Polish coast

Wójcik R., Pilarski M., Miętus M.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2014

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Vol. 2, Iss. 1

27--36

EN

The aim of this study was to recognize the possibility of downscaling probability density function (PDF) of daily precipitation by means of canonical correlation analysis (CCA). Sea level pressure (SLP) over Europe and the North Atlantic was used as a predictor. A skilful statistical model could be used to generate projections of future changes of precipitation PDF driven by GCM (General Circulation Model) simulations. Daily precipitation totals from 8 stations located on the Polish coast of the Baltic Sea covering the period 1961-2010 were used to estimate the gamma distribution parameters, and only wet days (i.e. ≥0.1mm) were taken in the analysis. The results of the Kolmogorov-Smirnov test and comparison of empirical and theoretical (gamma-distributed) quantiles proved that gamma distribution gives a reliable description of daily precipitation totals. The validation of CCA models applied to gamma parameters revealed that the reliable reconstruction of precipitation PDF is possible only for average long-term conditions. In the case of individual months/seasons the agreement between empirical and reconstructed quantiles is poor. This study shows the potential of modelling of precipitation PDF, however efforts should be made to improve model performance by establishing more reliable links between regional forcing and the variability of the gamma parameters.