The Experts below are selected from a list of 75 Experts worldwide ranked by ideXlab platform
Alan G Williams - One of the best experts on this subject based on the ideXlab platform.
-
effect of sampling procedure and strain variation in listeria monocytogenes on the discrimination of species in the genus listeria by fourier transform infrared spectroscopy and Canonical Variates Analysis
Fems Microbiology Letters, 1997Co-Authors: Dominique Lefier, David Hirst, Carl Holt, Alan G WilliamsAbstract:The ability to discriminate successfully among cultures of all species of the Listeria genus by infrared spectroscopy in combination with Canonical variate Analysis was confirmed. The robustness of the method was demonstrated by showing that the separation of L. monocytogenes and L. grayi was hardly affected by variations in broth medium, incubation temperature, incubation time and cell washing procedure. Discrimination among 24 strains of L. monocytogenes according to serotype allowed two groups to be recognised, one comprising serotypes 4 and 4b and the other containing serotypes 1, 1/2b and 1/2c. When strain variation was included in the species discrimination model, the classification of all the L. monocytogenes strains was virtually 100% correct.
Dominique Lefier - One of the best experts on this subject based on the ideXlab platform.
-
effect of sampling procedure and strain variation in listeria monocytogenes on the discrimination of species in the genus listeria by fourier transform infrared spectroscopy and Canonical Variates Analysis
Fems Microbiology Letters, 1997Co-Authors: Dominique Lefier, David Hirst, Carl Holt, Alan G WilliamsAbstract:The ability to discriminate successfully among cultures of all species of the Listeria genus by infrared spectroscopy in combination with Canonical variate Analysis was confirmed. The robustness of the method was demonstrated by showing that the separation of L. monocytogenes and L. grayi was hardly affected by variations in broth medium, incubation temperature, incubation time and cell washing procedure. Discrimination among 24 strains of L. monocytogenes according to serotype allowed two groups to be recognised, one comprising serotypes 4 and 4b and the other containing serotypes 1, 1/2b and 1/2c. When strain variation was included in the species discrimination model, the classification of all the L. monocytogenes strains was virtually 100% correct.
Gábor Speer - One of the best experts on this subject based on the ideXlab platform.
-
Different Gene Expression Patterns in the Bone Tissue of Aging Postmenopausal Osteoporotic and Non-osteoporotic Women
Calcified Tissue International, 2008Co-Authors: Bernadett Balla, János P. Kósa, János Kiss, Adrienn Borsy, János Podani, István Takács, Áron Lazáry, Zsolt Nagy, Krisztián Bácsi, Gábor SpeerAbstract:Purpose To identify genes that are differently expressed in osteoporotic and non-osteoporotic human bone and to describe the relationships between these genes using multivariate data Analysis. Methods Seven bone tissue samples from postmenopausal osteoporotic patients and 10 bone tissue samples from postmenopausal non-osteoporotic women were examined in our study. Messenger RNA was prepared from each sample and reverse transcribed to cDNA. The expression differences of 87 selected genes were analyzed in a Taqman probe-based quantitative real-time RT-PCR system. Results A Mann-Whitney U -test indicated significant differences in the expression of nine genes ( p ≤ 0.05). Seven of these nine genes–ALPL, COL1A1, MMP2, MMP13, MMP9, PDGFA, NFKB1—were significantly downregulated in the bone tissue of osteoporotic women, while CD36 and TWIST2 were significantly upregulated in osteoporotic patients. Principal components Analysis was used to evaluate data structure and the relationship between osteoporotic and non-osteoporotic phenotypes based on the multiple mRNA expression profiles of 78 genes. Canonical Variates Analysis demonstrated further that osteoporotic and non-osteoporotic tissues can be distinguished by expression Analysis of genes coding growth factors/non-collagen matrix molecules, and genes belonging to the Canonical TGFB pathway. Conclusion Significant differences observed in gene expression profiles of osteoporotic and non-osteoporotic human bone tissues provide further insight into the pathogenesis of this disease. Characterization of the differences between osteoporotic and non-osteoporotic bones by expression profiling will contribute to the development of diagnostic tools in the future.
Gerard Downey - One of the best experts on this subject based on the ideXlab platform.
-
Confirmation of brand identity of a Trappist beer by mid-infrared spectroscopy coupled with multivariate data Analysis
Talanta, 2012Co-Authors: Jasper Engel, Lionel Blanchet, Lutgarde M.c. C. Buydens, Gerard DowneyAbstract:Authentication of foods is of importance both to consumers and producers for e.g. confidence in label descriptions and brand protection, respectively. The authentication of beers has received limited attention and in most cases only small data sets were analysed. In this study, Fourier-transform infrared attenuated total reflectance (FT-IR ATR) spectroscopy was applied to a set of 267 beers (53 different brands) to confirm claimed identity for samples of a single beer brand based on their spectral profiles. Skewness-adjusted robust principal component Analysis (ROBPCA) was deployed to detect outliers in the data. Subsequently, extended Canonical Variates Analysis (ECVA) was used to reduce the dimensionality of the data while simultaneously achieving maximum class separation. Finally, the reduced data were used as inputs to various linear and non-linear classifiers. Work focused on the specific identification of Rochefort 8° (a Trappist beer) and both direct and indirect (using an hierarchical approach) identification strategies were studied. For the classification problems Rochefort vs. non-Rochefort, Rochefort 8° vs. non-Rochefort 8° and Rochefort 8° vs. Rochefort 6° and 10°, correct prediction abilities of 93.8%, 93.3% and 97.3%, respectively were achieved. © 2012 Elsevier B.V.
Carl Holt - One of the best experts on this subject based on the ideXlab platform.
-
effect of sampling procedure and strain variation in listeria monocytogenes on the discrimination of species in the genus listeria by fourier transform infrared spectroscopy and Canonical Variates Analysis
Fems Microbiology Letters, 1997Co-Authors: Dominique Lefier, David Hirst, Carl Holt, Alan G WilliamsAbstract:The ability to discriminate successfully among cultures of all species of the Listeria genus by infrared spectroscopy in combination with Canonical variate Analysis was confirmed. The robustness of the method was demonstrated by showing that the separation of L. monocytogenes and L. grayi was hardly affected by variations in broth medium, incubation temperature, incubation time and cell washing procedure. Discrimination among 24 strains of L. monocytogenes according to serotype allowed two groups to be recognised, one comprising serotypes 4 and 4b and the other containing serotypes 1, 1/2b and 1/2c. When strain variation was included in the species discrimination model, the classification of all the L. monocytogenes strains was virtually 100% correct.