This contribution is focused on the analysis of dynamic behavior of elastic continuum moving in liquid. The method of solution is demonstrated on the non-stationatr movement of a bar in a real, incompressible liquid. The principle of the solution is based on the modal transformation of the bar and discrete process using the finite element method (FEM). The problem is in general non-linear. However, the method introduced in this contribution allows the solution which provides gradual separation of the movement of liquid and the movement of the bar. This substitution is entered analogously on the finite element and is dependent on the normal coordinates. The result is a tensor of additional effects. and Obsahuje seznam literatury
This paper presents a variant of a mathematical model of continuum mechanics. Adaption of the model is focused on the unsteady term. The solution is based on the assumption of the zero value of the divergence vector, which can have a different physical meaning. and Obsahuje seznam literatury a názvosloví
In this paper we present new approach to the problem of conservation the small and endangered populations of black grouse. We elaborated and checked in the field non-invasive methods enabling to obtain the genetic material without removing birds from natal populations. The main idea is to mate the tame, especially accustomed hen from the aviary with wild cock. After mating the hen lays the eggs in the aviary and we obtain the first generation which has a half of the gene pool coming from the population of its father. Consecutive, repeated crossing the females from such broods with next wild males leads in few years to bring the genes from original population to the aviary in non-invasive manner. Another method is to collect semen from wild males using a stuffed female. We describe some technical methods of such manipulations with the birds and present some preliminary results. These methods enable obtaining birds bred in aviary for future program of reintroduction.
In this study we are adding further information to phylogeography of Pipistrellus pipistrellus complex by discovery of isolated mitochondrial lineages in Europe, from the island of Crete (Greece) and central Mediterranean (Sicily, Corsica) and by adding new data about geographic distribution of clades within the complex. We performed phylogeographic study with aid of partial sequence of cytochrome b and with focus to the radiation centre of this group in the Mediterranean Basin. Within the clade P. pygmaeus s.l., we have discovered isolated lineage from Crete, which is sister taxon to P. hanaki from Libya. We have detected the occurrence of P. pygmaeus s.str. in northern Iran. In the clade P. pipistrellus s.l. we have discovered isolated cluster represented by populations from Sicily and Corsica, with phylogenetic relation to Moroccan lineage. This is a first evidence of separated phylogroup within the complex from central Mediterranean. We refer the occurrence of P. pipistrellus s.str. from the island of Cyprus. These data represent further arguments for importance of the Mediterranean region in phylogeny of the P. pipistrellus species complex. Proposed allopatric speciation scenario considers the role of environmental fragmentation during the Messinian Salinity Crisis, strengthen by preference of mountain habitats in Mediterranean populations. The species status of Cretan and central Mediterraenan forms is also discussed.
In this review the authors outline traditional antiresorptive pharmaceuticals, such as bisphosphonates, monoclonal antibodies against RANKL, SERMs, as well as a drug with an anabolic effect on the skeleton, parathormone. However, there is also a focus on non-traditional strategies used in therapy for osteolytic diseases. The newest antiosteoporotic pharmaceuticals increase osteoblast differentiation via BMP signaling (harmine), or stimulate osteogenic differentiation of mesenchymal stem cells through Wnt/β-catenin (icarrin, isoflavonoid caviunin, or sulfasalazine). A certain promise in the treatment of osteoporosis is shown by molecules targeting non-coding microRNAs (which are critical for osteoclastogenesis) or those stimulating osteoblast activity via epigenetic mechanisms. Vitamin D metabolites have specific antiosteoporotic potencies, modulating the skeleton not only via mineralization, but markedly also through the direct effects on the bone microstructure., I. Zofkova, J. Blahos., and Obsahuje bibliografii
Protomyrmeleon daohugouensis sp. n. and Protomyrmeleon lini sp. n., two new species of Protomyrmeleontidae from the Middle Jurassic of Jiulongshan Formation are the first Chinese representatives of this Mesozoic odonatopteran family. The type specimen of P. lini is exceptionally well preserved, showing several particular wing and body structures that were unknown, viz. unique shape of tarsal claws, extreme thoracic skewness, presence of three pairs of long spurs on all femora and tibiae. The type "A" (sensu Nel et al., 2005) of wing venation (i.e. with a very long bridge between IR2 and RP3/4) corresponds to that of the protomyrmeleontid fore wing. The nearly complete absence of the meso-metathoracic interpleural suture, newly discovered in the Protomyrmeleontidae, can be considered as a synapomorphy of the clade Protozygoptera + Odonata.
First-stage larvae of camallanid nematodes Procamallanus (Procamallanus) laeviconchus (Wedl, 1862) and Procamallanus (Procamallanus) sp. from naturally infected Distichodus niloticus (Hasselquist) and Clarias gariepinus (Burchell), respectively, from Lake Turkana, Kenya (new geographical records) are described, being for the first time studied by scanning electron microscopy. Larvae of both species are characterised by the presence of a dorsal cephalic tooth, four submedian cephalic papillae and a pair of amphids, and by the elongate tail with several terminal digit-like processes. The latter formations probably serve for the attachment of larvae to the substrate in water when the larvae attract copepod intermediate hosts by their movements; these structures, especially their numbers, may be of taxonomic importance in camallanid nematodes.
Examination of the type material of Progrillotia dollfusi Carvajal et Rego, 1983, and of new specimens recently collected off the coast of Argentina (including plerocerci from 10 species of teleosts and adults from Squatina guggenheim Marini), allowed a detailed redescription of this species and the evaluation of its current taxonomic status. The following characters that have been treated inconsistently by different authors have been herein corrected or confirmed: band of hooklets on external surface restricted to the base of the tentacle, external surface of metabasal region with 3-5 intercalary hooks arranged in a single row merging immediately to a cluster of 3-4 hooklets arranged in two rows; retractor muscle originating in the posterior third of the bulb, hollow hooks, and posterior margin of bothria notched. These features along with the presence of postovarian testes in the adults clearly confirm the placement of P. dollfusi in the genus Grillotia Guiart, 1927. In order to avoid the homonymy with Grillotia dollfusi Carvajal, 1971, a new name, Grillotia carvajalregorum nom. n., is proposed. This species differs from the 16 valid species in the genus in the combination of the following characters: number and morphology of hooks in principal rows in proximal metabasal region of the tentacle, number and distribution of intercalary hooks, presence of clusters of hooklets, extent of band of hooklets on external surface of basal armature, site of origin of the retractor muscle, and features of the terminal genitalia. The present study describes the plerocerci and adult worms, and provides detailed description of the microthrix pattern and histology of this species for the first time.