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Lestidae is a heterogeneous family with more than 150 species worldwide. There are many debates concerning its resolution. One of them is whether the genus Chalcolestesshould be recognized as a genus or considered as a synonym of Lestes. We compared male characteristics of eight Hungarian species of three genera (Lestes, Chalcolestesand Sympecma) of the family Lestidae to get closer to the answer. We analysed the morphometry of genital and non-genital characteristics and the morphology of the secondary genitalia, especially the ligula. The morphometric analyses showed that two Chalcolestesspecies were the biggest in the most of the cases while Sympecma fusca(Vander Linden, 1820) and Lestes virens(Charpentier, 1825) were the smallest. The genera were separated mainly by the genitalic traits in the morphometric analyses. The differences in the secondary genitalia strengthen the generic status of Chalcolestes.

Nanoshell formation has been studied experimentally in Ag/Au and Ag/Pd systems in a hemispherical geometry at different temperatures. The void formation in these systems is the result of pure Kirkendall-porosity formation, because it is caused mainly by the inequality of the intrinsic atomic fluxes and other effects (e.g. stresses), inevitably present during nanoshell formations in solid state reactions (oxides, sulphides), can be less important or can be neglected. The kinetics of the process was followed by Transmission Electron Microscopy. Both the growth and shrinkage regimes of the process were observed at the same temperature and even the temperature dependence of the characteristic time (tcr) describing the crossover of the two different regimes was observed. We succeeded to show that tcr shifts to smaller values with increasing temperature. This confirms the theoretical results:the growth and the shrinkage regimes are controlled by the faster as well as the slower diffusion coefficients (DA as well as DB), respectively. It is also illustrated that, confirming recent theoretical predictions, the pore radius linearly depends on the initial particle radius and the slope of this straight line increases with the average composition of the faster component.

Interdiffusion in Zn/InSb system has been investigated under high (0.59×106 G) and low (1 G) gravity conditions at 673, 593 and 573K, respectively. Samples annealed at 0.59×106 G, 673K for 60 hours, indicated the formation of a periodic reaction layer structure. Since such structures can be formed in solid state reactions of ternary systems [, the effect of high gravitational field and high hydrostatic pressure (approximately 3kbar) in the formation of periodic patterns was investigated. Systematic investigations at ambient pressure and low gravitational field were carried out at 593 and 573 K in sandwich geometry. SEM and EDX analysis had shown that there are different phases between the initial components. Starting from the Zn side of the specimen there is a very thin single-phase with high (about 90%) In content. Next to it is a thin two-phase layer, containing mainly 50-50% InSb and some elongated Zn particles and then there is a thick phase with the composition of Zn5In2Sb4 which is followed by a similar two-phase mixture (InSb+Zn) similar to the Zn side of the sample. Although the diffusion zone is not a well developed periodic structure, but every layer (clearly distinguishable form the others and was either a single-or multiphase layer) grows with the time.

Morphometric and genetic differences were analysed for two closely related damselflies, Chalcolestes viridisand C. parvidens. A total of 305 male individuals were collected from six European countries (Austria, Croatia, Germany, Greece, Hungary and Portugal). Measurements from a total of 28 populations of C. viridisand C. parvidensand several intermediate forms were collected to determine if they can be definitely distinguished using simple morphometric characters. DNA sequences from two independent loci (nuclear ribosomal ITS region and mitochondrial cytochrome oxidase I gene) were analysed to test whether these taxa represent separate monophyletic groups as well as to compare the genetic distance with those found between well-accepted European Lestesspecies. Discriminant analysis revealed that C. viridisand C. parvidensare differentiated in morphometric space. Individuals with intermediate anal appendage traits overlapped with both C. viridisand C. parvidenswhich raised the possibility that they are merely subspecies of a single species. However, genetic analysis of both investigated DNA regions showed that the two Chalcolestestaxa did not share haplotypes, indicating their status as true species. Furthermore, they formed a monophyletic group separated from the investigated Lestesspecies, supporting the recognition of the genus Chalcolestes. The two Chalcolestesspecies are very closely related compared with European Lestesspecies, suggesting that their divergence occurred relatively recently.

A population of Amphora micrometraGiffen, collected in September 2002 from different habitats in Laguna Blanca in the Bolivian Altiplano, South America, has been examined using light transmission and scanning electron microscopy. The original description of this species is incomplete and insufficient to characterize the taxon in the light of the newly collected ultrastructural data. The holotype of A. micrometrawas examined during the present study and compared to Bolivian specimens. An emended diagnosis of A. micrometrausing all available information is provided. A taxonomic discussion based on available literature and the ecology of the taxon is also presented herein.

In a set of recent papers we have shown that the diffusion asymmetry in diffusion couples (the diffusion coefficient is orders of magnitude larger in one of the parent materials) leads to interesting phenomena: i) sharp interface remains sharp and shifts with non Fickian (anomalous) kinetics [1-5], ii) originally diffuse interface sharpens even in ideal (completely miscible) systems [6,7], iii) an initially existing thin AB phase in A/AB/B diffusion couple can be dissolved [8], iv) there exists a crossover thickness (typically between few nanometers and 1m) above which the interface shift turns back to the Fickian behaviour [9], v) the growth rate of a product of solid state reaction can be linear even if there is no any extra potential barrier present (which is the classical interpretation of the “interface reaction control” for linear kinetics) [10]. These latter results will be summarized and reformulated according to the usual expression for linear-parabolic law containing the interdiffusion coefficient, D, and interface transfer coefficient, K. Relation between the activation energies of D and K will be analyzed and compared with available experimental data.

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