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Abstract  

Neutron activation analyses of ground samples of safe-packing insulation have shown that dust from different sources may be differentiated by trace element content. Between 10 and 20 elements were identified in each of 54 samples, and comparison of the activation “fingerprints” offers a good prospect for positively or negatively matching two or more samples.

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Cereal Research Communications
Authors: L.R. Vemireddy, N. Ranjithkumar, A. Vipparla, M. Surapaneni, G. Choudhary, K.V. Sudhakarrao, and E.A. Siddiq

India bred high yielding rice varieties have enriched to a great extent the global rice germplasm since the mid-sixties. Systematic research efforts for development of cultivar-specific DNA fingerprints of major Indian rice cultivars, however, have not received due attention. The present investigation was aimed at development of DNA fingerprints for 90 high yielding rice varieties using hypervariable microsatellite (hvRM) markers. A panel of eight markers, viz. RM11313, RM13584, RM15004, RM5844, RM22250, RM22565, RM24260 and RM8207 was chosen from 52 polymorphic markers based on their highly polymorphic nature, SSR repeat type and number and ability to distinguish genotypes, in order to develop DNA fingerprints of 90 varieties. The remaining high polymorphic hvRM markers could be of immense value in future to distinguish new cultivars, in case they could not be distinguished by the 8 marker panel. Four of the 8 markers, viz. RM22250, RM13584, RM24260 and RM5844 were located in expressed genes and could be of value in DUS (Distinctness, Uniformity and Stability) testing. Thus we suggested, that this set of 8 loci could be used as standard for DNA fingerprinting of Indian rice cultivars.

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Abstract  

Adverse health effects of occupational exposures to metal-containing airborne particles have long been recognized. To reduce the adverse effects caused by metal-containing particles, it is important to make clear where they are from. SPM has been applied to the study of the sources of chromium, manganese, nickel and zinc in aerosol particles PM10. Micro-PIXE spectra of single particles were treated as fingerprints since each particle was characterized by its micro-PIXE spectrum. The sources of the metal-containing particles were identified using the fingerprints of single particles. The study shows that the major sources of the four kinds of metals in the air are metallurgic emission, vehicle exhaust, coal combustion and soil dust.

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Summary  

Single aerosol particles were analyzed in the ambient air of the center of Shanghai by scanning proton microprobe to obtain characteristic X-ray spectra (micro-PIXE) which were considered to be the fingerprints of these aerosol particles. The origin of the lead-containing particles was identified by the combination of the micro-PIXE spectra with pattern recognition technique. It was found that the most of the lead-containing particles were derived from vehicle exhaust, coal combustion and soil dust.

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We describe an application of DSC as an analytical ‘fingerprinting’ method that has been used to characterize the thermal properties of wheat starch in low-moisture, wheat-flour-based baked products, including cookies, crackers, and pretzels. This use of DSC has enabled us to relate starch thermal properties, on the one hand, to starch structure, and on the other hand, to starch functionality, in terms of baking performance and finished-product quality.

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The profiles of anthocyanins and anthocyanidins present in berry fruits can be used as fingerprints for the evaluation of authenticity of raw materials, juices, fruit extracts, and food products. The aim of our work was to establish the authenticity of fruit juices from the market according to the label inscription. With this end in view, we used spectroscopic and TLC techniques for the preliminary identification of main groups of anthocyanins and to obtain a fingerprint of each berry fruit used in the preparation of juice. For the same purpose, we achieved a RP-HPLC method for the determination in detail of the composition of natural pigments, such as anthocyanins from alcoholic extracts of colored fruits and anthocyanidins from their hydrolyzed products. The RP-HPLC chromatographic fingerprints gave us the possibility to identify seventeen anthocyanins (glycosylated anthocyanidins) and five major anthocyanidins (delphinidin, cyanidin, petunidin, pelargonidin, and malvidin) from the extracts of colored fruits.The TLC separation was achieved on cellulose pre-coated plates developed with concentrated hydrochloric acid-glacial acetic acid-water as mobile phase followed by densitometric measurements in visible. The HPLC separation was carried out on ODS-2 Hypersil column by gradient elution and detection at 520 nm. The mobile phase was a mixture of acetonitrile and phosphoric acid buffer in different ratios.Our methods have been successfully applied to find the fingerprint of anthocyanins and anthocyanidins of eight berry fruits which we used as reference materials at the analysis of fruit juices from market in order to establish their authenticity and conformity with the label inscription.

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Abstract  

An abbreviated NAA procedure has been developed to fingerprint obsidian artifacts in the Mesoamerican region. Despite the large number of available sources, an NAA procedure, which relies on producing short-lived isotopes, has been applied with a success rate greater than 90 percent. The abbreviated NAA procedure is rapid and cost competitive with the XRF technique more often applied in obsidian sourcing. Results from the analysis of over 1,200 obsidian artifacts from throughout Mesoamerica are presented.

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Abstract  

Nuclear microprobe was used to measure single aerosol particles (SAPs) indoors from Shanghai. Every particle is characterized with its micro-PIXE spectrum, which can be considered as the fingerprint of the SAPs. The pattern recognition technique (PR) was applied to trace the SAPs back to their source. Results of five monitor homes at different locations in Shanghai show that most of the measured indoor aerosol particles are derived from soil dust, cement dust, vehicle exhaust, coal boilers and steel mill dust.

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Summary

The objective of this study was to explore the possibility of combining headspace gas chromatography with mass spectrometric detection (HS-GC-MS) and 13C NMR spectroscopy to enhance the detectability of components of the essential oils of medicinal plants of the Salvia genus. Preliminary investigations were performed with two sage species, Salvia lavandulifolia and Salvia triloba, known for particularly abundant yields of their respective essential oils. By use of HS-GC-MS, characteristic fingerprints of the volatile fractions were obtained for plant species from two different vegetation seasons (2007 and 2008). Partial identification of the components of these volatile fractions was performed, and comparison of the chromatographic fingerprints confirmed seasonal fingerprint similarity within the same species. Preliminary 13C NMR measurements resulted in well shaped spectra with an abundance of regularly distributed signals. This suggested the possibility of using 13C NMR spectroscopy in phytochemical research, in parallel with HS-GC-MS, to enhance the detectability of volatile components of plant species belonging to this genus.

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Summary

The merits of chemometrics in categorizing different Egyptian olive chemovarieties based on their compositional integrity were implemented in this study. Fingerprints of 9 different olive leaves varieties cultivated in Egypt were established using reversed-phase high-performance thin-layer chromatography (RP-HPTLC) prior to and after post-chromatographic derivatization with natural product-polyethylene glycol (NP/PEG) reagent and image analysis using ImageJ® software in order to build 2 separate data matrices. The chromatographic fingerprints were separately subjected to unsupervised pattern recognition multivariate analysis to build 2 separate models using principal component analysis (PCA) and hierarchical clustering analysis (HCA) algorithms to explore the distribution pattern of different chemovarieties. The second model which involved olive samples’ fingerprints after post-chromatographic derivatization exhibited greater ability to reveal a broader spectrum of phytoconstituents with enhanced sensitivity. Densitometric RP-HPTLC quantification of oleuropein marker was compared to image analysis approach using Sorbfil TLC Videodensitometer® by newly developed and validated methods. Densitometry exhibited better performance characteristics than image analysis method and therefore was executed for determination of oleuropein concentration in the 9 Egyptian olive varieties. Oleuropein marker solely was found to be inadequate for standardization of olive leaves varieties. This study demonstrated a comprehensive approach for the rapid classification of different Egyptian olive varieties, which is crucial to warranting their chemical-consistency and, thereafter, effective consistency.

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