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Thirty-two taxa representing 12 sections of the genus Hypericum were analyzed along with two representatives of Thornea using nuclear ITS sequences in order to assess the scope of phylogenetic relationships in this species-rich genus. The resulting parsimony analysis corroborates the actual classification and interspecific affinities. The molecular data provide support for the monophyletic assemblage of the sections Androsaemum, Olympia and Drosocarpium and for the polyphyletic origin of Ascyreia, Hypericum, Taeniocarpium, Myriandra and Adenosepalum. The earlier evolutionary hypotheses concerning the origin of H. balearicum and H. calycinum, and the relatedness of Adenosepalum representatives, are not supported by our data analysis. The obtained results encourage the use of ITS sequence analysis in resolving the phylogenetic relationships within the member-rich genus Hypericum.

The restriction fragment length polymorphism (RFLP) analysis of three non-coding regions within a large single copy of chloroplast genome are used to examine the phylogenetic relationships among 9 species of genus Hypericum. The PCR-amplified products of regions psaA-trnS, trnC-trnD and psbC-trnS were digested separately with five restriction endonucleases. Gels were scored in a binary format. Wagner parsimony analysis has been performed on the obtained data matrix. A high level of the interspecific variation was detected while intraspecific was not observed. The obtained results indicate discrimination of H. calycinum L. and H. androsaemum L. as the most primitive species in this sample as well as grouping of two related species H. perforatum L. and H. tetrapterum Fries. Also, relation between H. olympicum L. and H. adenotrichum Spach. is closer in terms of the cpDNA analysis than on morphological grounds, while H. richeri subsp. grisebachii (Boiss.) Nyman. is more distant. H. montanum L. is more related to advanced species while relationships of H. hirsutum L. with the other taxa was not resolved completely. The obtained results identifies three intragenic chloroplast DNA regions useful for phylogenetic or phylogeographical analysis in Hypericum.

The development of concrete technology through several centuries is systematically presented. Until the middle of last century, the strength of concrete was considered to be the property of highest significance for practical use. Experts attempted to relate all other properties to the strength. Development of new concrete types characterized by high and very high strength and performance is described and it is emphasized that their development resulted from increasingly strict durability requirements. It is expected that the so called &#8220 ; ; smart concrete&#8221 ; ; will be developed in the 21st century. This new type of concrete is expected to solve some of the difficulties currently experienced with the above mentioned technologies.

Sustavno je prikazan višestoljetni razvoj tehnologije betona kroz nekoliko stoljeća. Sve do sredine ovog stoljeća čvrstoća betona smatrala se glavnim svojstvom za njegovu uporabu. Sva druga svojstva nastojalo se dovoditi u vezu sa čvrstoćom. Opisuje se razvoj betona visokih čvrstoća i performansi do kojih se došlo na osnovi zahtjeva za povećanom trajnošću, te razvoj betona vrlo visokih čvrstoća i performansi. U 21. stoljeću predviđa se razvoj tzv. “pametnih betona” pomoću kojih će se rješavati neki od problema u vezi s navedenim tehnologijama.

The new bridge over the river Sava in Zagreb is described. This project has won the first price in the competition for conceptual design. An original and functional prestressed construction is chosen, which has been known as “extradosed prestressed bridge”.