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Heterogeneous reactions of solid nickel(II) complexes, XI

The influence of different experimental conditions on the stoichiometry of thermal decomposition of the complex Ni(NCS)2(β-picoline)4

Journal of Thermal Analysis and Calorimetry
Authors: T. Šramko, G. Liptay, and E. Jóna

The influence of factors caused by different experimental conditions on the stoichiometry of thermal decomposition of the complex Ni(NCS)2(β-picoline)4 was studied. By means of TG it was found that the release ofβ-picoline was shown by the derivatograph (air atmosphere, sample of 50–500 mg, rate of temperature increase 1–6°/min, crucible with a hole in the bottom) in three steps (−2, −1, −1), by the micro-balance (sample of 2.59 mg) in two steps (−2, −2), and by the vacuum thermobalance in one step (−4). Under quasi-isothermal and quasi isobaric conditions in a special crucibleβ-picoline was released in three steps (−1, −2, −1). An analogous result was obtained with the derivatograph using a crucible with a lid. The reasons for these differences are discussed.

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The taxonomy of the genus Bulbocodium , in which two European species, a smaller eastern (B. versicolor) and a more robust western (B. vernum) are included, has been controversial since the description of the eastern species in 1821. Nuclear encoded ribosomal DNA ITS1 and the entire chloroplast DNA ITS were sequenced from several European populations, from France to the Ukraine, and the leaf width of mature living individuals was measured and analysed by ANOVA and Tukey-test. Although the studied DNA regions proved to be invariable, leaf width shows extreme variability. We found no correlation between the leaf size of the individuals and the geographical position of the populations, and in addition, the sequenced DNA regions showed total uniformity. Thus, our results do not support the division of the genus Bulbocodium into two taxa, at least in the sampled area. The formerly described size variants can be treated taxonomically at the forma level.

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Acta Botanica Hungarica
Authors: Sh. Almerekova, Zs. Lisztes-Szabó, N. Mukhitdinov, M. Kurmanbayeva, K. Abidkulova, and G. Sramkó

The central Asian narrow endemic species Oxytropis almaatensis is a highly endangered plant with a very restricted distribution in the Tian Shan Mountains. In this study, we present the basic conservation genetic characteristics of this species based on a DNA fingerprinting approach in order to provide yardsticks for official conservation agencies to develop an informed conservation strategy. The three currently known populations with two allopatric subpopulations at each site were sampled in the Trans-Ili Alatau Mountains (S Kazakhstan) and subject to AFLP analysis using four primer combinations. This was supplemented by flow cytometry of plants with remarkably different body sizes to check for possible ploidy differences. The presence or absence of AFLP bands was used in downstream analyses utilising various population genetic approaches. Genetic diversity of O. almaatensis was found to be on the upper end of the spectrum typical for other outcrossing species of similar life-history characteristics. Most of the genetic variation was attributable to within (sub)population variance, and we also found a remarkable gene flow between the populations. However, the geographically closer populations were found to be more close to each other genetically, and population differentiation showed the same pattern with a significant isolation by distance. Similar patterns were not found for subpopulations of the geographically more close populations, and the subpopulations living along the same river valley were found to be genetically more cohesive. Flow cytometry did not reveal any difference in DNA content between the small and large forms of the species. All these results suggest the presence of two separate populations at the three localities of this species. Conservation efforts should focus on these two populations, and, given the relatively high genetic diversity within each population, both ex situ and in situ conservation measures can be effectively carried out based on the currently known populations of this narrow endemic species.

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Acta Botanica Hungarica
Authors: Cs. Molnár, Zs. Molnár, Z. Barina, N. Bauer, M. Biró, L. Bodonczi, A. Csathó, J. Csiky, J. Deák, G. Fekete, K. Harmos, A. Horváth, I. Isépy, M. Juhász, J. Kállayné Szerényi, G. Király, G. Magos, A. Máté, A. Mesterházy, A. Molnár, J. Nagy, M. Óvári, D. Purger, D. Schmidt, G. Sramkó, V. Szénási, F. Szmorad, Gy. Szollát, T. Tóth, T. Vidra, and V. Virók

The first version of the map of the Hungarian vegetation-based landscape regions were prepared at the scale of 1: 200,000 (1 km or higher resolution). The primary goal of the map was to provide an exact background for the presentation and evaluation of the data of the MÉTA database. Secondly, we intended to give an up-to-date and detailed vegetation-based division of Hungary with a comprehensive nomenclature of the regions. Regions were primarily defined on the basis of their present zonal vegetation, or their dominant extrazonal or edaphic vegetation. Where this was not possible, abiotic factors that influence the potential vegetation, the flora were taken into consideration, thus, political and economical factors were ignored. All region borders were defined by local expert botanists, mainly based on their field knowledge. The map differs in many features from the currently used, country-wide, flora-or geography-based divisions in many features. We consider our map to be temporary (i.e. a work map), and we plan to refine and improve it after 5 years of testing.

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