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Abstract  

The k 0-based internal monostandard neutron activation analysis (IM-NAA) method was used for the analysis of 30 large and non-standard geometry ancient pottery samples obtained from Buddhist sites of Andhra Pradesh, India. One freshly finished pottery and a sun-drenched pottery were also analyzed for comparison. Samples were irradiated in thermal column facility of Apsara reactor and also in graphite reflector position of critical facility of Bhabha Atomic Research Centre. Radioactive assay was carried out using a 40% relative efficiency HPGe detector coupled to MCA. Concentration ratios of 15 elements with respect to Sc were determined. The La/Ce values as well as statistical cluster analysis utilizing concentration ratios of elements were used for grouping/provenance of the potteries.

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‘Egusi’ melon Citrullus lanatus (Thunb.) Matsum. & Nakai is an important vegetable crop in Nigeria, grown for its edible seeds and oils. The diverse areas in which the crop is cultivated make it a rich source of genetic resources for the species. To explore its diversity, 50 accessions of ‘egusi’ melon were collected from different agro-ecological parts of Nigeria and were evaluated using 25 simple sequence repeat (SSR) markers. A total of 49 bands were scored, of which 42 were polymorphic, accounting for 93.60% of the polymorphic loci. The PIC value ranged from 0.36–0.80. UPGMA cluster analysis revealed five distinct groups for SSR. PCA analysis revealed the distinction of the accessions NG/OE/MAR/09/014, NG/TO/APR/09/027 and A8. Based on the results of this study, SSR markers appear to be particularly useful for the estimation of genetic similarity among diverse accessions of melon.

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Molecular polymorphism of six species of Thysanoptera of both sexes, collected from different locations and host plants in Hungary was studied by using RAPD-PCR technique. The specimens were classified according to sampling sites (Gödöllo, Nagykovácsi and Valkó), host plants (Lathyrus tuberosus, Medicago sativa, Taraxacum officinale, Trifolium pratense), sexes, and larvae in case of Aeolothrips intermedius. On the basis of the total of 103 fragments generated by 15 RAPD primers the genetic distances were calculated by cluster analysis using simple matching method. The dendrogram resulted in two main groups: Aeolothripidae (Aeolothrips intermedius) and Thripidae (Frankliniella intonsa, Kakothrips robustus, Odontothrips confusus, Thrips dilatatus and T. tabaci). Within the family Thripidae two subgroups were observed including (i) F. intonsa, T. dilatatus and T. tabaci, and (ii) K. robustus and O. confusus. Two population-specific and one sex-linked fragments were identified by the RAPD primers, OPQ14, NO11 and OPA08, respectively.

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Abstract  

Laguna del Plata (Cordoba, Argentina) is a small saline lake connectedto Laguna Mar Chiquita. Its level fluctuations have changed notably throughthe centuries with both high level (HLP) and low level (LLP) periods. Theradionuclides 226 Ra and 210 Pb were analyzed in a core to determine datesand sedimentation rates. The elements As, Ba, Br, Co, Cr, Cs, Fe, Hf, Na,Rb, Sb, Sc, Se, Ta, Th, U, Zn, Zr and rare earth Ce, Eu, La, Lu, Nd, Sm, Tband Yb were determined by instrumental neutron activation analysis. Statisticalanalysis of elemental concentrations (cluster analysis) reflects the associationof the samples along the core according to the provenance of the sedimentsand if they had been deposited during HLP or LLP.

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Abstract  

The objective of this paper is to depict the knowledge array of standards. This is done by identifying and analyzing external effects, specifically spillover effects. The database used is Perinorm. We use a cluster analysis in order to create groups of technology fields for German standards according to the fields of the International Classification of Standards. Methodologically, the distances between these objects or clusters are defined by the chosen distance measure, which in turn is determined by the sum of their cross references. The applied joining clustering method uses these distances between the objects and allows the data to be mapped within a two dimensional space. The results of this mapping show the existence of structures within the standards data fitting to the well-known structure of patent spillovers.

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A new method of solvent classification is proposed based on the five system constants of the solvation parameter model for transfer of neutral compounds from the gas phase to solvent and hierarchical cluster analysis for identifying solvents with similar properties and for organizing them into selectivity groups. This method resulted in the classification of 36 common solvents used in chromatography into seven selectivity groups with four solvents (2,2,2-trifluoroethanol, N,N-dimethylformaide, dimethyl sulfoxide, and water) behaving independently. Except for water, the three organic solvents identified as independent are probably a consequence of the lack of other solvents with similar properties in the data set rather than a demonstration of unique solvent behavior. The classification scheme provides a logical approach for solvent selection as the first step in chromatographic method development. A similar approach using the solvation parameter model suitable for the transfer of neutral compounds between condensed phases and hierarchical cluster analysis was used to classify 19 aqueous and 17 totally organic biphasic partition systems for liquid-liquid extraction. The dynamic range of system constants for the aqueous biphasic systems was not great, and selectivity differences were dominated by the high cohesion and strong hydrogen-bond acidity of water. The aqueous biphasic partition systems were classified into three general groups and a fourth dispersed group characterized by high mutual solubility. In contrast, the totally organic biphasic partition systems exhibit an almost continuous range of properties with minimal group formation demonstrating a wider and complementary range of selectivity to the aqueous biphasic systems. The classification of the liquid-liquid partition systems provides a suitable method for the identification of systems for sample preparation based on liquid-liquid extraction and for the simulation of extractions for target compound isolation.

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Abstract  

The study deals with the application of cluster analysis (CA) and non-parametric tests (Shapiro–Wilk, Kruskal–Wallis, Dunn, U Mann–Whitney) to classify and interpret of a monitoring data set for Odra River water quality assessment based on concentration values of radiochemical parameters. The data set represents results for 3 alpha emitters (210Po, 238U and 239+240Pu) measured in surface water samples collected at 13 different sampling locations (5 in major Odra stream while 8 in Odra tributaries) within four seasons: winter, spring, summer and autumn, in the framework of 1 year-term quality monitoring research. The correlation analysis of polonium, uranium and plutonium data indicates that significant values of Spearman’s correlation coefficient appears between 210Po and 239+240Pu (r = 0.55 in autumn and 0.77 in winter as well as 0.49 in all year), while statistical significant correlation between uranium and plutonium as well as uranium and polonium were not found. In the Odra drainage basin, the biggest differences were observed in the case of 238U. The hypothesis about possible geographic and seasonal differences between concentration of 210Po, 238U and 239+240Pu in the Odra River catchment area was verified by cluster analysis (CA). Finally, to asses if there are statistically significant differences in mean concentration value of 210Po, 238U and 239+240Pu for Vistula and Odra Rivers drainage basins were obtained by used of the non-parametric tests. Comparing to Vistula catchment area, statistically different concentration of 210Po and 239+240Pu in all year was observed for river samples collected on Odra drainage basin.

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Scientometrics
Authors: Edgar Schiebel, Marianne Hörlesberger, Ivana Roche, Claire François, and Dominique Besagni

Abstract  

Scientific progress in technology oriented research fields is made by incremental or fundamental inventions concerning natural science effects, materials, methods, tools and applications. Therefore our approach focuses on research activities of such technological elements on the basis of keywords in published articles. In this paper we show how emerging topics in the field of optoelectronic devices based on scientific literature data from the PASCAL-database can be identified. We use Results from PROMTECH project, whose principal objective was to produce a methodology allowing the identification of promising emerging technologies. In this project, the study of the intersection of Applied Sciences as well as Life (Biological & Medical) Sciences domains and Physics with bibliometric methods produced 45 candidate technological fields and the validation by expert panels led to a final selection of 10 most promising ones. These 45 technologies were used as reference fields. In order to detect the emerging research, we combine two methodological approaches. The first one introduces a new modelling of field terminology evolution based on bibliometric indicators: the diffusion model and the second one is a diachronic cluster analysis. With the diffusion model we identified single keywords that represent a high dynamic of the mentioned technology elements. The cluster analysis was used to recombine articles, where the identified keywords were used to technological topics in the field of optoelectronic devices. This methodology allows us to answer the following questions: Which technological aspects within our considered field can be detected? Which of them are already established and which of them are new? How are the topics linked to each other?

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. [29]. D.L. Massart L. Kaufman 1983 The Interpretation of Analytical Data by the Use of Cluster Analysis

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Cereal Research Communications
Authors: Alojzije Lalic, Josip Kovacevic, Gordana Šimić, Georg Drezner, and Vlado Guberac

Everitt, B.: 1980. Cluster analysis. London, Heinemann educational books Everitt B. Cluster analysis 1980

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