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

Approaching the socialist factory and its workforce: considerations from fieldwork in (former) Yugoslavia

The socialist factory, as the ‘incubator’ of the new socialist (wo)man, is a productive entry point for the study of socialist modernization and its contradictions. By outlining some theoretical and methodological insights gathered through field-research in factories in former Yugoslavia, we seek to connect the state of labour history in the Balkans to recent breakthroughs made by labour historians of other socialist countries. The first part of this article sketches some of the specificities of the Yugoslav self-managed factory and its heterogeneous workforce. It presents the ambiguous relationship between workers and the factory and demonstrates the variety of life trajectories for workers in Yugoslav state-socialism (from model communists to alienated workers). The second part engages with the available sources for conducting research inside and outside the factory advocating an approach which combines factory and local archives, print media and oral history

Diagenetic relationships between sulphur species and formation of pyrite in coals and sediments

Based on the abundant minerals in a Miocene freshwater sequence of mixed sediments (pieces of coal in clays, sand-stones and shales) alternating with coal layers, the following main sedimentation environments were distinguished: illite-montmorillonitic (I-M), calcitic (Ct) and coal-forming environment. Applying factor analyses to 16 geochemical parameters, an environmentally- specific early diagenetic connection between the sulphur transformation processes, amount of Corg and precursor material species (C27-C29-steranes) was determined. It was found that the effects of limiting factors on Spyr formation depended on the hydrogeochemical conditions of individual sedimentation environments. Pyrite formation in coals depended directly on participation of higher plant precursor materials and/or on the total sulphur content in the system. In the MS, pyrite formation directly depended on total sulphur content, hydrogeological conditions and the amount of Corg

Pyrite formation in organic-rich clay, calcitic and coal-forming environments

The early diagenetic characteristics of pyrite formation processes in a Miocene freshwater sequence of mixed sediments (coal fragments in clays, sandstones or shales) alternating with continuous brown coal layers was investigated. Based on abundant minerals, the following main sedimentary environments were distinguished: the illite-montmorillonitic (I-M), calcitic (Ct) and coal-forming environment (CL). For these hydrogeochemically differing environments the effects of limiting factors on the pyrite formation process (availability of sulphate and Fe, amount of organic matter and participation of organic sulphur) were assessed by correlation analysis. Significant differences in the effects of these limiting factors in the particular environments were observed. These differences were explained taking in account the different oxidative activity, Fe-complex and surface complex forming properties of humic substances in dependence of pH of environment and the abundance of sorptionally active clay minerals. In environments having a relatively low pH and containing clay minerals (I-M-and CL-environments) the oxidative activity of humic substances (Hs) on pyrite precursors was greatly prevented however pyrite formation depended on reactive Fe availability as the consequence of complex formation. On the contrary, in environments with a relatively high pH, as it was the calcitic, the oxidative activity of Hs was greatly enhanced, thus oxidizing the sulfur precursors of pyrite. The oxidation degree of organic matter was probably also a consequence of the differing activity of the humic electron-acceptors

'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

Chick embryo back skin organ and fibroblast cultures. Extracellular matrix change induced by dialysate fluid and uraemic toxins in relation to proliferation and differentiation processes

Aim: During uraemia, an increase of middle molecules and acetylpolyamines occurs. In vitro the middle molecules produce cell toxicity, while the acetylpolyamines stimulate cell proliferation and differentiation. These phenomena are related to protein and extracellular glycosaminoglycan production. The aim of the present study was to evaluate the activity of dialysate, dialysate fluid and the chromatographic peaks of dialysate fractionated by G-15 Sephadex column on chick embryo skin development. Methods: We evaluated the effects of protein and glycosaminoglycan synthesis using monolayer and organotypic cultures. Results: Our data show that dialysate, chromatographic peak II, and 261028M N1-acetylspermine cause inhibition of chick embryo skin culture development. On the contrary, 1028M N-acetylornithine and dialysate fluid increase protein and extracellular glycosaminoglycan synthesis, whereas chromatographic peak I does not reveal differences when compared to controls. Conclusions: These extracelluar changes are related to cell proliferation and feather formation in chick embryo organotypic culture. Moreover, the pH changes of culture medium do not influence the biological action of acetylpolyamines and dialysate fluid on protein and extracellular glycosaminoglycan synthesis. Cell death in the presence of N1acetylspermine, dialysate and peak II appears unrelated to the apoptotic process. The data show that acetylpolyamines, dialysis fluid, dialysate and chromatographic peaks act on fibroblasts, and are able to modify glycosaminoglycan synthesis. The organotypic cultures of chick embryo back skin could represent a model for studying the modifications of the extracellular matrix induced by these substances