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Journal of Radioanalytical and Nuclear Chemistry
Authors: Andreza Ribeiro, Ana Figueiredo, Regina Ticianelli, Georges Nammoura-Neto, Natália Silva, Mauricio Kakazu, and Guilherme Zahn

Abstract  

São Paulo is the largest city in Brazil and South America with about 20 million inhabitants in the metropolitan area, more than nine million motor vehicles and intense industrial activity, which are responsible for increasing pollution in the region. Nevertheless, little is known concerning metal and semi-metal content in the soils of this metropolitan region. This type of information could be extremely useful as a fingerprint of environmental pollution. The present study determined the elements As, Ba, Co, Cr, Sb, and Zn concentrations in soils adjacent to avenues of highly dense traffic in São Paulo city to assess their levels and possible sources. The analytical technique employed was Instrumental neutron activation analysis. The results showed, except for Co, concentration levels higher than the reference values for soils of São Paulo, according to the Environmental Protection Agency of the State of São Paulo guidelines. When compared to similar studies in other cities around the world, São Paulo soils presented higher levels, probably due to its high density traffic and industrial activity. The concentrations obtained for As and Cr indicate anthropogenic origin. The high levels of the traffic-related elements Ba, Sb, and Zn in soils nearby high density traffic avenues indicate they may originate from vehicular exhausts.

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Summary  

Chemistry fingerprint of materials helps determine provenance and technological production techniques, and, therefore, is useful way to study interaction between prehistoric people. In this work 38 ceramic fragments from Justino and São José sites, in Brazilian northeast, were analyzed using instrumental neutron activation analysis (INAA). The recognition of the compositionally homogeneous group within of the database was performed by means of principal component (PC). The PC scores were calculated on the matrix covariance of the log base 10 transformed concentration values, and grouping was sought in the PC scores using Kernel Density Estimates (KDE). By using KDE from PC scores two chemically different groups were found. Discriminant analysis was performed to assess the groups' validity. Despite of the pottery from Justino and São José sites present same technical profile, different of the Tupiguarani and Aratu traditions, it was obtained that Justino and São José samples are constitute of distinct ceramic pastes. This result can be understood in terms of the cultural influences in the preparation of the ceramic past and that potteries analyzed are originate locally.

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Abstract  

On the basis of the measured time-dependent distribution of references in recent scientific publications, we formulate a novel model on the ageing of recent scientific literature. The framework of this model is given by a basic set of mathematical expressions that allows us to understand and describe large-scale growth and ageing processes in science over a long period of time. In addition, a further and striking consequence results in a self- consistent way from our model. After the Scientific Revolution in 16th century Europe, the 'Scientific Evolution' begins, and the driving processes growth and ageing unavoidably lead - just as in our biological evolution - to a fractal differentiation of science. A fractal structure means a system build up with sub-systems characterised by a power-law size distribution. Such a distribution implies that there is no preference of size or scale. Often this phenomenon is regarded as a fingerprint of self-organisation. These findings are in agreement with earlier empirical findings concerning the clustering of scientific literature. Our observations reinforce the idea of science as a complex, largely self-organising 'cognitive eco-system'. They also refute Kuhn's paradigm model of scientific development.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Yinsong Wang, Aiguo Li, Yuanxun Zhan, Lun Wei, Yan Li, Guilin Zhang, Yaning Xie, Jing Zhang, Yuanmao Zhang, and Zuci Shan

Abstract  

The atmospheric particulate matter samples were collected in Shanghai, China. The X-ray absorption near-edge structure (XANES) spectra of Cr, Mn, Cu and Zn were measured. The XANES spectroscopy was used as a fingerprint to compare with that of reference materials to obtain speciation information. The oxidation state of these elements and main chemical components in the samples were described using the method. The results show that in our samples the oxidation state of Cr is trivalent, Mn mainly exists in the divalent state, Cu also exists in the divalent state, and Zn mainly exists in the zinc sulfate. For the XANES spectra of samples with different particle size and from different sampling site, we did not find their obvious differences. When we compared the XANES spectra of our samples with those of standard reference material SRM 1648, we found that they are similar in regards to the determined elements. The elemental concentrations in the samples were determined by proton induced X-ray emission (PIXE). The difference of elemental concentrations was observed in the different samples.

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Abstract  

The thermal analysis methods (TG, DTG and DTA) were used for the investigation of the thermal degradation of some recent manufactured tanned leathers, leathers that are supports of cultural or historical objects (leather from book covers (XVII-XIX centuries); leather from an Austrian belt (Franz Joseph period), Cordoba leather (XVII century), lining leathers), recent and patrimonial parchments and recent extracted collagen (sorts of collagen obtained from bovine leather at different pH-values, bovine collagen with different hydration degree). At progressive heating, all investigated materials exhibit two main successive processes, associated with the dehydration and thermo-oxidative degradation. Each analyzed material has a characteristic thermal analysis curve (TG, DTG and DTA) that can be considered a material 'fingerprint'. This result suggests the use of the thermal analysis methods to identify of leathers from which the patrimonial objects are manufactured. The rate of thermo-oxidation of recent manufactured tanned leathers is substantially higher than the rate of the same process corresponding to naturally aged leathers that exhibit values of the thermo-oxidation rate appropriate to those obtained for parchments and collagens. The rate of thermo-oxidation of leather can thus be used as a criterion to distinguish between recent manufactured leather and patrimonial one.

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Experiments were performed to study changes caused by irradiation or high hydrostatic pressure pasteurization of liquid egg white by differential scanning calorimetry, spectrofluorimetry, electronic nose measurements and NIR-spectrometry. The non-thermal pasteurization treatments were also assessed in relation to loss of carotenoid content, and lipid- and cholesterol oxidation of liquid egg yolk. Unlike radiation pasteurization, high pressure processing caused protein denaturation in egg white, which manifested in changes of its DSC-thermogram and intrinsic tryptophan fluorescence. Electronic nose testing showed changes of the head-space volatile composition of egg albumen, particularly as a function of radiation treatment. Both treatments caused changes in the NIR-spectrometric “fingerprint” of the liquid egg white. Various chemometric analyses of the results of the latter instrumental methods, particularly statistical techniques developed by the group of one of the co-authors of this article, demonstrated the potential for detection and characterization of the applied non-thermal processing techniques on liquid egg white. Irradiation induced more carotenoid degradation and lipid oxidation in liquid egg yolk than pressure processing.

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Acta Biologica Hungarica
Authors: O. Törjék, E. Kiss, J. Kiss, M. Kondrak, G. Gyulai, J. Gergácz, and László Heszky

/IPC Welsh, J., McClelland, M. (1990) Fingerprinting genomes using PCR with arbitrary primers. Nucleic Acids Res. 18 , 7213-7218. Fingerprinting genomes using PCR with arbitrary primers Nucleic Acids

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Aerva lanata collected during summer, monsoon and winter were subjected to similar extraction conditions as well as sample application conditions on precoated silica 60F254 TLC plates. The plates were developed in ethyl acetate-toluene (7:3 v/v) in order to study the seasonal variation in HPTLC fingerprints. A similar procedure was also followed for the plant samples collected from three different states of India, in order to study the geographical variation. p-Hydroxybenzoic acid, used as reference standard for comparison with each sample, was observed in samples collected in all three seasons but in different concentrations. The compound was also observed in samples collected from Gujarat and Maharashtra, but was found to be absent in the sample from Kerala. The sample from Kerala showed a different compound at R F 0.74, having a λ max of 280 nm. This compound exhibited a spectrum very different from that of p-hydroxybenzoic acid having a λ max of 252 nm, which separates out at R F 0.73 on the plate. The proposed method was validated according to ICH guidelines in terms of linearity, accuracy and specificity, intra-day and inter-day precision, repeatability of measurement of peak area, repeatability of sample application and specificity. The calibration graph was found to be linear over a range of concentration of 25.0–175.0 ng, with a regression coefficient of 0.9986. Determination of accuracy by standard addition method at three different concentration levels returned a mean recovery value of 97.24 ± 7.36. Intra-day and inter-day precision values were found to be less than 2%. The relative standard deviations (RSDs) of repeatability of sample application and measurement of area were found to be 1.24% and 0.93%, respectively.

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The extraction of crude drugs by using different solvents provides polarity-based fractions containing specific types of secondary metabolites. Averrhoa carambola L. fruits were extracted and fractionated, and petroleum ether extract was processed by fatty acid methyl ester (FAME) technique for characterization by gas chromatography‒mass spectrometry (GC‒MS) analysis. The remaining part was extracted with methanol for high-performance thin-layer chromatography (HPTLC) analysis, for simultaneous quantitative determination of gallic acid, protocatechuic acid, and quercetin in methanolic fractions. Petroleum ether and methanol fractions were found to be the best for the highest possible recovery of target analytes. The chromatographic elutions of FAME compounds generated from ether extract were evaluated by GC‒MS profiling. Ten fatty acid compounds were separated with the highest quantity of oleic acid methyl ester (42.88%). On other hand, polar fraction was processed by HPTLC profiling. For achieving good separation, a mobile phase of toluene‒ethyl acetate‒formic acid (5:4:1, v/v) was used. The densitometric determination was carried out at 310 nm in reflection–absorption mode. The calibration curves were linear in the range of 100–600 ng per spot for gallic acid, protocatechuic acid, and quercetin. During the analysis, the dried raw material from A. carambola L. fruits showed the presence of gallic acid (0.96%), protocatechuic acid (0.05%), and quercetin (0.40%). The proposed method is simple, precise, specific, and accurate. The statistical analysis of the data obtained proves that the method is reproducible and selective and can be used for the routine analysis of the reported phenolic compounds in crude drug and extracts. The results indicated that the methanolic extracts of the plant contained a considerable amount of bioactive compounds. The presence of phytochemicals especially phenolics and flavonoids explains its use in various diseases. It may be concluded that the results obtained from the quantitative evaluation of quercetin by HPTLC fingerprinting could be useful in its authentication, the quality control of the drug, and in ensuring therapeutic efficacy.

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Availability of markers that distinguish commercially important premium Basmati rice varieties from cheaper Basmati or non-Basmati indica rice varieties is of interest to exporters, commercial suppliers and consumers to ensure the varietal purity of Basmati rice supplies. In this study, a fingerprint database of 27 rice varieties including commercially important traditional Basmati (TB), cross-bred (evolved) Basmati and some non-Basmati indica rice varieties has been prepared using 50 microsatellite markers. A total of 271 electromorphs (alleles) were detected at 50 SSR (simple sequence repeat) loci, 92 of which were observed only in 2–10 of the 16 Basmati rice varieties. Notably, 7–10 of the sixteen Basmati rice varieties had the same Basmati specific electromorphs at RM562, RM551 and RM547 loci. Alarge number of unique (22) and null (16) electromorphs were noticed in Basmati rice varieties. A combination of four SSR markers (RM224, RM248, RM547 and RM594) can be used to differentiate all the 27 rice varieties. Specific SSR markers have been identified for the authentication of Premium Basmati rice cultivars such as Taraori Basmati (RM547, RM594 and RM511), Basmati 370 (RM252, RM426 and RM527), Karnal Local (RM248, RM423 and RM488) and Pusa 1121 (RM252, RM400 and RM410), and for the detection of adulterant like Sharbati (RM215, RM423 and RM259). SSR database reported here, shall broaden the list of SSR markers already recommended for varietal identification and detection of adulteration in Basmati rice supplies.

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