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Detailed studies of the gas release profiles of minerals and rocks reveal differences in the degassing rates and degassing temperatures and also in the compositions of the fluids evolved from the samples.

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Abstract  

Three component percolative W/O microemulsions were studied by differential scanning calorimetry. Water-AOT-Decane, D2O-AOT-Decane, Water-AOT-Isooctane and Water-Ca(AOT)2-Decane systems were analyzed. Thus by changing, in the order, the dispersed phase, the dispersing medium, and by modifying the interphase region. The thermal history of the samples was monitored by a suitable thermal program. Following the latter, first order phase transitions associated with the freezing and/or melting of the two massive phases were obtained, as well as the higher order phase transition associated with the percolation process. From the melting spectra an estimate of the amount of water bound to the hydrophilic groups of the AOT as well as of that of oil bound to the hydrophobic surfactant tails was obtained. The latter result shows a difference in the behaviour of the continuous oily phase at the O/W interphase. From the freezing spectra, the percolative character of the microemulsion was evidenced by the exotherms associated with the freezing of the water phase.

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The evolution of individual anthocyanins during vinification of Merlot and Pinot Noir grapes was studied using two different winemaking procedures for each grape variety. Additionally, the effect of the applied vinification on the anthocyanin composition of the obtained wine at the end of maceration and wine aged 6 months was investigated and compared with the anthocyanin patterns of the original grape. The dynamics of the extraction process was monitored daily during maceration by analysing the anthocyanins in the must using HPLC. The results showed that the anthocyanin composition of young wines was different from that of the grapes. The proportions of malvidin-3- glucoside and malvidin-acetate were higher in wines than in the grape skins, but this was not the case for malvidin coumarate. Application of different vinification procedures to the same raw material resulted in wines with similar anthocyanin patterns. However, the anthocyanin profiles changed with the ageing of the wines.

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During the last century wheat landraces were replaced by modern wheat cultivars leading to a gradual process of genetic erosion. Landraces genotyping and phenotyping are strategically useful, as they could broaden the genetic base of modern cultivars. In this research, we explored Single Nucleotide Polymorphism (SNP) markers diversity in a collection of common and durum wheats, including both landraces and Italian elite cultivars. A panel of 6,872 SNP markers was used to analyze the genetic variability among the accessions, using both the Principal Components Analysis (PCA) and the Neighbour Joining clustering method. PCA analysis separated common wheat accessions from durum ones, and allowed to group separately durum landraces from durum elite cultivars. The Neighbour joining clustering validated PCA results, and moreover, separated common wheat landraces from common elite cultivars. The clustering results demonstrated that Italian durum landraces were poorly exploited in modern breeding programs. Combining cluster results with heterozygosity levels observed, it was possible to clarify synonymy and homonymy cases identified for Bianchetta, Risciola, Saragolla, Timilia and Dauno III accessions. The SNP panel was also used to detect the minimum number of markers to discriminate the studied accessions. A set of 33 SNPs were found to be highly informative and used for a molecular barcode, which could be useful for cultivar identification and for the traceability of wheat end-products.

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Abstract  

Authorship identity has long been an Achilles’ heel in bibliometric analyses at the individual level. This problem appears in studies of scientists’ productivity, inventor mobility and scientific collaboration. Using the concepts of cognitive maps from psychology and approximate structural equivalence from network analysis, we develop a novel algorithm for name disambiguation based on knowledge homogeneity scores. We test it on two cases, and the results show that this approach outperforms other common authorship identification methods with the ASE method providing a relatively simple algorithm that yields higher levels of accuracy with reasonable time demands.

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Two different botanical sources, Eclipta alba and Wedelia calendulacea are used as “Bhringaraja” in the Ayurvedic s ystem o f medicine. In the present study, an effort has been made to evaluate different sources by using high-performance thin-layer chromatography (HPTLC) as an analytical tool. Wedelolactone, one of the primary constituents of these plants, was taken as the marker compound for the evaluation. An HPTLC method was developed and validated for the evaluation of different sources of “Bhringaraja”. The chromatographic system was developed using silica gel 60 F254 HPTLC plates with the mobile phase toluene–chloroform–ethyl alcohol–formic acid (5:4:1:0.5, v/v). Linearity was found between the concentration ranges of 80 to 280 ng spot−1 (R 2: 0.9994), and limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.36 ng spot−1 and 1.09 ng spot−1. The study has shown the presence of wedelolactone at the concentration of 0.26% w/w and 0.05% w/w in E. alba and W. calendulacea, respectively, whereas it was absent in another closely related species, Wedelia trilobata. At the same time, all the three plants were subjected to evaluation of quality-control parameters as per the World Health Organization (WHO) guidelines. Certain parameters such as foaming index, total alkaloids, and total bitter principles were significantly different in the three plants. Hence, the present HPTLC method development, and the validation and evaluation of quality-control parameters would be helpful in the standardization of individual plants and their formulations.

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The newly emerged chromatographic fngerprint analysis represents a rational approach assessment of Traditional Chinese Medicine (TCM) and its preparations. In the present paper, a quick and reliable analytical method was developed for the quality assessment of QiYi capsules (QY) using high-performance thin-layer chromatography (HPTLC) with the reference of Tripterygium wilfordii. The unique properties of the HPTLC fngerprint were validated by analyzing 10 batches of QY samples. The 9 common peaks of the HPTLC images of QY and the different RF and peak area ratios of the chemical distribution could directly discern the stability by comparison of 10 samples, and also, the 9 common peaks were selected to evaluate the similarities of QY; the similarities of 10 batches of QY were more than 0.960, which indicated a standardized consistency and reliable quality of QY. Therefore, the newly developed HPTLC fngerprint method provided an easy way for sample characterization and differentiation; it allowed for the quality assessment of QY capsules with the reference of T. wilfordii.

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Brurberg, M. B., Hannukkala, A. and Hermansen, A. (1999): Genetic variability of Phytophthora infestans in Norway and Finland as revealed by mating type and fingerprint probe RG57. Mycol. Res. 103 , 1609-1615. Genetic

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