A laboratory experiment, carried out for five months, was designed to assess the effects produced by the neonicotinoid Actara 25 WG, used at a dose recommended by the manufacturer, in the dynamics of the populations of epigeic Eisenia fetida (Sav.) and Dendrobena veneta (Rosa)earthworms. The study was conducted in a climatic chamber and involved balanced biomass of mature specimens representing both species, in 3 replications of soil medium with the insecticide, in addition to controls. The growing populations were inspected five times, by means of manual segregation of the substrate. The insecticide led to an increase in both the number of specimens and the biomass of E. fetida population (overall, as well as mature and immature worms), yet it reduced their reproduction (decreased the number of cocoons) (p<0.05). In the case of D.veneta, the neonicotinoid insecticide produced positive effects only in the mature specimens (p<0.05).
W artykule przedstawiono wybrane wyniki badań nad technologią jednoczesnego kształtowania drążonych odkuwek wałków stopniowanych wraz z uzwojeniami ślimaków metodą obciskania obrotowego. Zaproponowano przy tym, aby odkuwki wytwarzane były z półfabrykatów rurowych ze stopu tytanu w gatunku Ti6Al4V. Analizę teoretyczną oparto na modelowaniu numerycznym, które przeprowadzono metodą elementów skończonych w oprogramowaniu Simufact Forming. W trakcie symulacji określono przydatność technologii obciskania obrotowego do kształtowania drążonych odkuwek z uzwojeniami ślimaków. Wyznaczono zakres parametrów stabilnego przebiegu procesu, ponadto rozpoznano czynniki, które mogą wpływać negatywnie na przebieg procesu kształtowania oraz jakość uzyskanych odkuwek. Uzyskane wyniki potwierdziły możliwość obciskania obrotowego drążonych odkuwek ze stopów tytanu wraz z uzwojeniami ślimaków.
EN
This paper presents selected results of the research on developing a process for forming hollow stepped shafts with worms by rotary compression. It is proposed that these parts be formed from a hollow billet made of titanium alloy Ti6Al4V. The proposed method is modelled numerically by the finite element method using the Simufact Forming simulation software. In the simulations, we tested whether the rotary compression technique is suitable for manufacturing hollow parts with worms. We determined a range of process stability-ensuring parameters and identified factors that can have a negative effect on the forming process and product quality. The results confirm that hollow titanium alloy shafts with worms can be manufactured by rotary compression.
W pracy przedstawiono typowe zagrożenia, na jakie narażony jest współczesny użytkownik komputera. W szczególności analizowano zmiany, jakie zaszły w zachowaniu zarówno szkodliwego oprogramowania, jak i metod ataku stosowanych w ostatnich dwunastu miesiącach. Przedstawiona analiza obejmuje drugie półrocze 2007 r. oraz pierwsze półrocze 2008 roku. Zwrócono uwagę na pojawiające się nowe typy zagrożeń oraz na aktualne kierunki ewolucji szkodników.
EN
In this paper the typical risks of the nowaday's computer user are presented. Especially the changes in operation of malware as well as the methods of attack used in the recent twelve months are subject of analysis. The presented research covers the second half of 2007 and the first half of 2008. The newly appearing types of vulnerabilities and the direction of malware evolution are focused on.
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Phosphatized palaeoscolecid cuticle fragments of Palaeoscolex lubovae sp. nov., P. spinosus sp. nov., Palaeoscolex sp. and Sahascolex labyrinthus gen. et sp. nov., as well as disarticulated sclerites, are described from the Early Cambrian Sinsk Formation (Siberian Platform) at the Achchagyy Tuoydakh fossil-Lagerstatte. These remarkably well preserved arrays of plates and platelets display ornamentation identical to widely reported isolated sclerites assigned to Hadimopanella, Kaimenella, Milaculum, and Utahphospha. The precise relationship of the Palaeoscolecida to the priapulids or alternatively with the nematomorphs remains under discussion, but suggested is their systematic position within the superphylum Ecdysozoa, comprising moulting animals. some of the described cuticular trunks exhibit distinction between the dorsal and ventral sides: nodular sclerites occur on the dorsal and spiny sclerites on the ventral sides of the worm body. Such a pattern of ornamentation may suggest adaptation for a level-bottom, vagile benthic and probably epifaunal mode of life. The Siberian palaeoscolecids are compared with the type species of Palaeoscolex, P. piscatorum Whittard, 1953, and with palaeoscolecid worms from Australia, Bohemia and China. Sclerites recorded with microplates accreted into the basal brim may support a hypothesis that the more complex sclerite structure bearing a series of nodes was derived from simple small sclerites with single node. The biostratigraphic utility of isolated sclerites remains low, because of the same morphology occur in different sclerites may occur in one scleritome.
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Phosphatic, discoidal sclerites with prominent nodes on the external surface have been found in Upper Cambrian inter-reef calcareous grainstone of the Mila Formation in the Shahmirzad section, Alborz Mountains, northern Iran. This is the first record of a palaeoscolecid worms from Iran. Isolated sclerites demonstrate a complex ornamentation characteristic of the widely known species Hadimopanella oezgueli GEDIK 1977 and are interpreted as dermal plate elements of Palaeoscolecida. Hadimopanella sclerites are known outside Iran from adjacent areas including Turkey, Kirgizia and China and from the more distant continents of Australia, Antarctica, Siberia, Baltica (Sweden, Estonia) and peri-Gondwanan Europe (Spain). The Iranian palaeoscolecid worms were probably infaunal constituent of bentic marine community in inter-reef environment. The utility of isolated sclerites for Cambrian biozonation is stillrather low
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