Effect of NaCl on seed germination in some Centaurium Hill. Species (Gentianaceae)

The influence of high NaCl concentrations on seed germination in both light and darkness was examined in the species Centaurium pulchellum, C. erythraea, C. littorale, C. spicatum, and C. tenuiflorum. Salt tolerance was found to depend on the life history of the seeds. To be specific, seeds of all five species failed to complete germination when exposed to continuous white light if kept all the time in the presence of 100-200 mM and greater NaCl concentrations. However, when after two weeks NaCl was rinsed from the seeds and the seeds were left in distilled water under white light for an additional two weeks, all species completed germination to a certain extent. The percent of germination not only depended on NaCl concentration in the prior medium, but was also species specific. Thus, seeds of C. pulchellum, C. erythraea, and C. littorale completed germination well almost irrespective of the salt concentration previously experienced. On the other hand, seeds of C. tenuiflorum completed germination poorly if NaCl concentrations in the prior media were greater than 200 mM. When seeds after washing were transferred to darkness for an additional 14 days, they failed to complete germination if previously imbibed on media containing NaCl concentrations greater than 400 mM. However, the seeds of all species, even if previously imbibed at 800 mM NaCl, could be induced to complete germination in darkness by 1 mM gibberellic acid. .Uticaj visokih koncentracija NaCl na klijanje semena, kako na svetlosti tako i u tami, ispitivano je kod vrsta Centaurium pulchellum, C. erythraea, C. littorale, C. spicatum i C. tenuiflorum. Tolerantnost ovih biljaka na natrijum-hlorid zavisi od životnog ciklusa semena. Zapravo, semena svih pet ispitivanih vrsta nisu završavala klijanje kada su bila izložena kontinuelnoj beloj svetlosti u prisustvu 100-200 mM i pri većim koncentracijama. Pored toga, semena svih ovih vrsta, izložena imbibiciji na 800 mM NaCl, mogla su biti indukovana da završe klijanje u mraku uz dodatak 1 mM giberelinske kiseline. .nul

Dynamics in the dimerised and high field incommensurate phase of CuGeO3_3

Temperature ($2.3<T<40$\ K) and magnetic field ($0<B<17$\ T) dependent far infrared absorption spectroscopy on the spin-Peierls coumpound CuGeO$_3$\ has revealed several new absorption processes in both the dimerised and high field phase of CuGeO$_3$. These results are discussed in terms of the modulation of the CuGeO$_3$\ structure. At low fields this is the well known spin-Peierls dimerisation. At high fields the data strongly suggests a field dependent incommensurate modulation of the lattice as well as of the spin structure.Comment: 12 pages (revtex), 2 figures (eps), csh selfextracting .uu file, To appear in PRB-Rapid Com

Risk assessment of trace element contamination in river sediments in Serbia using pollution indices and statistical methods: a pilot study

To effectively manage potential environmental and human health impacts of contaminated river sediments, it is important that information about the source (anthropogenic vs geogenic), variability and environmental risks associated with the contamination are well understood. The present study was carried out to assess the source and severity of contamination and to undertake a risk assessment for selected elements (As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V and Zn) in river sediments in Serbia. The estimate of the anthropogenic component of contamination was derived by determining the total element content and the background values for elements in sediments, and the severity of pollution was assessed by calculating a number of pollution indices including the contamination factor, the enrichment factor, the index of geoaccumulation, the ecological risk factor, the potential ecological risk index, the pollution load index, the combined pollution index, the modified degree of contamination and the toxic unit factor. This analysis indicates that river sediments in Serbia are primarily polluted with Zn, Cu and Cd. The most contaminated river systems are the Ibar, Pek, West Morava and Great Morava rivers. Mining activities were found to have a significant influence on sediment. Multivariate analyses suggested anthropogenic origins for Pb, Zn, Cd, As, Ni and Cu, whilst Fe, V, Mn, Co and Cr appear to have a mixed origin (both lithogenic and anthropogenic sources). A geochemical approach, with a calculation of pollution indices and statistical methods, is recognised as useful for the risk management of trace elements in sediments around the world.Sanja Sakan, Gordana Dević, Dubravka Relić, Ivan Anđelković, Nenad Sakan, Dragana Ðorđevi

'It's all the same, only he's not here'?: popular music and political change in post-Tuđman Croatia

While Franjo Tuđman was the president of Croatia (1990–99), popular music and other forms of entertainment were heavily structured around the key presidential narratives: Croatia’s political and cultural independence from Yugoslavia, and the idea that Croatia’s war effort had been purely defensive. After Tuđman, the Croatian music industry had to cope with media pluralism and the transnational challenges of the digital era. Patriotic popular music expressed an oppositional narrative of Euroscepticism and resistance to the Hague Tribunal, yet Croatia retained and expanded its position in the transnational post-Yugoslav entertainment framework, undermining a key element of Tuđman’s ideology