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Kamila Rawojć, Dorota M. Tarnawska, Justyna U. Miszczyk, Jan Swakoń, Liliana Stolarczyk and Marzena Rydygier

References 1. Van del Kogel, A., & Joiner, M. (2009). Basic clinical radiobiology. United Kingdom: Hodder Education. 2. Fenech, M., Holland, N., Chang, W. P., Zeiger, E., & Bonassi, S. (2003). HUMN project: detailed description of the scoring criteria for the cytokinesis-block micronucleus assay using isolated human lymphocyte cultures. Mutat. Res., 534, 65-75. 3. IAEA. (2001). Cytogenetic analysis for radiation dose assessment. A manual. Vienna: International Atomic Energy Agency. (Technical Reports Series no

Open access

Linli Zhu, Yu Pan and Jiangtao Wang

al. [ 8 ], Agapito et al. [ 9 ], Umadevi et al. [ 10 ] and Cohen [ 11 ]). The model of ontology can be regarded as a graph G = ( V , E ), in which each vertex v expresses a concept and each edge e = v i v j represents a directly contact between two concepts v i and v j . The aim of ontology similarity calculating is to learn a similarity function Sim : V × V → ℝ + ∪ {0} which maps each pair of vertices to a score real number. Moreover, the purpose of ontology mapping is to bridge the link between two or more different ontologies based on the

Open access

H Hasebe and S Suhara

Abstract

In order to judge the quality of tobacco leaf, it is necessary to conduct sensory smoke evaluations. However, these are subjective and the results are difficult to quantify. Therefore, we have attempted to establish a quantitative method for evaluating tobacco quality by comparing results of headspace analysis. Forty-seven leaf samples of different types (flue-cured, Burley, Oriental) were analyzed. The first step in this study was to have a panel of experts smoke cigarettes made from the test tobaccos and have them evaluate 10 sensory attributes. The scores were then analyzed by the technique of principal component analysis (PCA). Results showed that the score for the flavor note attribute indicated the type of tobacco and the scores of the other 9 attributes were combined as a total to indicate smoking quality. Following the sensory study, headspace vapors of the test tobaccos were analyzed with a headspace sampler, gas chromatography, mass spectroscopy system (HS-GC-MS), in which the gas sampling loop and the HS-GC transfer line were deactivated. In order to obtain conditions for good reproducibility, the heating temperature and time of the headspace vials were examined. PCA was performed for the headspace vapor (HSV) analysis results for 31 selected peaks. The first and second principal components could be used to classify tobacco types. The third principal component partially indicated differences of smoking qualities. Finally, multiple regression analysis was performed on the HSV analysis results in order to estimate the smoking quality scores. The regression model of all samples combined had a low regression coefficient. Then, we separated the results of the three tobacco types, as we considered that the headspace data might reveal information about the classifications themselves. The final outcome was a regression model that could be applied to each type with a higher accuracy. The variables that entered the models were compared.

Open access

S Dagnon, R Tasheva, A Stoilova, D Christeva and A Edreva

Abstract

Levels of valeric acids (isovaleric and 3-methylvaleric) in leaves and smoke of different tobacco types were quantified by capillary gas chromatography (GC) using flame ionization detector (FID). The aroma characteristics of the smoke were scored by sensory evaluation. It was found that leaves of Oriental and burley tobaccos contain higher amounts of both valeric acid derivatives than Virginia tobaccos containing isovaleric acid but no 3-methylvaleric acid. Strong correlation between the aroma and pleasantness scores of smoke and the content of valeric acids in the leaves of Oriental tobaccos was observed, while it was not the case for leaves of Virginia and burley tobaccos. In all tobacco types no correlation between smoking characteristics and the content of valeric acids in the smoke was established. Regression models involving leaf isovaleric acid were developed that can be used to evaluate aroma and pleasantness of smoke in Oriental tobaccos. The data obtained allow the following conclusions to be drawn: a) 3-methylvaleric acid may be a chemical marker to distinguish Virginia tobaccos from Oriental and burley tobaccos; b) isovaleric acid content in leaves of Oriental tobaccos may be used for objective aroma evaluation that can be exploited for breeding and market purposes.

Open access

F Heinzer, HP Maitre, M Rigaux and J Wild

Abstract

The first part of the paper describes a new method of obtaining reproducible and meaningful headspace profiles of tobacco lamina by using a modified closed loop stripping apparatus. The complex chromatograms are obtained by high-resolution glass capillary gas chromatography. The second part summarizes the results of a chemometric approach to interpret the chromatograms obtained from a series of nine Virginia flue-cured tobaccos from different origins and belonging to different quality groups, each one analysed three times by the method described above. After the elimination of peaks containing redundant information, the resulting data set, consisting of 27 × 17 data points, was analysed to detect natural groupings by using an in-house program (in Basic) for principal component analysis. A subsequent discriminant analysis yielded two discriminant functions capable of separating the nine Virginia tobaccos into three quality groups as defined by a conventional organoleptic analysis carried out by a smoking panel. All the tobaccos could be classified correctly (100 %). A first attempt to classify, by the procedure described above, a group of six Virginia tobaccos whose organoleptic scores were not known, did not yield clearly interpretable results, possibly because the performance of the capillary column used for analysis had slightly deteriorated during the experiment with resultant changes in retention characteristics, which led to wrong identifications of certain peaks.

Open access

Naoyuki Ishida

Summary

A comprehensive analytical method using liquid chromatography atmospheric pressure chemical ionization mass spectrometry detector (LC/APCI-MSD) was developed to determine key non-volatile components with low polarity elucidating holistic difference among tobacco leaves. Nonaqueous reversed-phase chromatography (NARPC) using organic solvent ensured simultaneous separation of various components with low polarity in tobacco resin. Application of full-scan mode to APCI-MSD hyphenated with NARPC enabled simultaneous detection of numerous intense product ions given by APCI interface. Parameters for data processing to filter, feature and align peaks were adjusted in order to strike a balance between comprehensiveness and reproducibility in analysis. 63 types of components such as solanesols, chlorophylls, phytosterols, triacylglycerols, solanachromene and others were determined on total ion chromatograms according to authentic components, wavelength spectrum and mass spectrum. The whole area of identified entities among the ones detected on total ion chromatogram reached to over 60% and major entities among those identified showed favorable linearity of determination coefficient of over 0.99. The developed method and data processing procedure were therefore considered feasible for subsequent multivariate analysis. Data matrix consisting of a number of entities was then subjected to principal component analysis (PCA) and hierarchical clustering analysis. Cultivars of tobacco leaves were distributed far from each cultivar on PCA score plot and each cluster seemed to be characterized by identified non-volatile components with low polarity. While fluecured Virginia (FCV) was loaded by solanachromene, phytosterol esters and triacylglycerols, free phytosterols and chlorophylls loaded Burley (BLY) and Oriental (ORI) respectively. Consequently the whole methodology consisting of comprehensive method and data processing procedure proved useful to determine key-components among cultivars of tobacco leaves, and was expected to additionally expand coverage that metabolomics study has ensured. [Beitr. Tabakforsch. Int. 27 (2016) 60-73]

Open access

Sylwester Sommer, Iwona Buraczewska, Katarzyna Sikorska, Teresa Bartłomiejczyk, Irena Szumiel and Marcin Kruszewski

. F., Beinke, C., Deperas, M., Gregoire, E., Koivistoinen, A., Lindholm, C., Moquet, J., Oestreicher, U., Puig, R., Rothkamm, K., Sommer, S., Thierens, H., Vandersickel, V., Vral, A., & Wojcik, A. (2014). Validation of semi-automatic scoring of dicentric chromosomes after simulation of three different irradiation scenarios. Health Phys., 106(6), 764-771. DOI: 10.1097/HP.0000000000000077. 4. Thierens, H., Vral, A., Vandevoorde, C., Vandersickel, V., de Gelder, V., Romm, H., Oestreicher, U., Rothkamm, K., Barnard, S., Ainsbury, E., Sommer, S., Beinke

Open access

Lucyna Samek, Zdzislaw Stegowski and Leszek Furman

/Absolute Principal Component scores and UNMIX. Sci. Total Environ ., 372 , 278–286. DOI: 10.1016/j.scitotenv.2006.08.041. 4. Samek, L. (2012). Source apportionment of PM10 fraction of particulate matter collected in Krakow, Poland. Nukleonika , 57 (4), 601–606. 5. Samek, L., Gdowik, A., Ogarek, J., & Furman, L. (2016). Elemental composition and rough source apportionment of fine particulate matter in Krakow, Poland. Environ. Prot. Eng. (in press). 6. Almeida, S. M., Pio, C. A., Freitas, M. C., Reis, M. A., & Trancoso, M. A. (2006). Approaching PM2.5 and PM2

Open access

Guillermo de Anda-Jáuregui, Cristobal Fresno, Diana García-Cortés, Jesús Espinal Enríquez and Enrique Hernández-Lemus

regimes among chromosomes in breast cancer transcriptomes. Fig. 2 Model validation. A heatmap depicting Z-scored relative likelihood – as measured by adjusted coefficient of determination R2 – for the four models. Rows correspond to chromosomes, while columns correspond to the four models for nonscaled distance. Green tones correspond to low-to-negative scores, while the dark and red colours represent positive-to-high scores. 3.1 Decay of gene–gene correlations The model discrimination analysis we performed indicates that the best goodness of fit (by

Open access

E. Navarro-Pardo, L. González-Pozo, P. Villacampa-Fernández and J.A. Conejero

Assessment tool [ 23 ]. Scoring is done on a 3-point scale ranging from 0 to 2, where 0 represents the most impairment and 2 the best performance. The maximum overall score is 28 as a result of combining the Gait Scale (12 points max.) and the Balance Scale (16 points max.). The Cronbach’s α obtained for the reliability of the overall scale was .95, showing excellent internal consistency. 2.4 Design and procedure We developed a randomized controlled trial with two times of assessment and data gathering. The present investigation was favorably informed by