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New data allow us to correlate the Early Cambrian archaeocyathan faunas of the Appalachian (eastern)and Cordilleran (western) faunal provinces of Laurentia. The precise relationships of fossil assemblages between these provinces have hitherto been controversial, with the correlation of the Elliptocephala asaphoidesFauna posing particular problems. New and revised data (including the new taxa Sekwicyathus tillmaninov. sp. Debrenne & A. Zhuravlevand Archaeosycon balsaminov. sp. Debrenne & A. Zhuravlevon archaeocyathan assemblages from the Appalachians New Jersey and Virginia allow correlation of these assemblages to the middle Bonnia-OlenellusZone of the Pacific Laurentia (Late Botoman) and the Elliptocephala asaphoidesFauna with the middle-upper Bonnia-OlenellusZone (Late Botoman-Early Toyonian). The Appalachian archaeocyathan assemblages are not endemic but originated from archaeocyaths of the Pacific Region in or near the Middle Botoman; then, during the Middle Botoman-Late Botoman, they migrated northward along the Appalachian margin of Laurentia (in term of modern coordinates). We discuss here the development and the extent of influence of the Hawke Bay regressive event, and the pattern of archaeocyathan migration as the Appalachian margin of Laurentia drifted northward into equatorial latitudes.

AbstractIn the Early Cambrian, there were two peaks of the increase in number of new archaeocyathan genera. These diversification bursts are, perhaps, related to significant changes in Early Cambrian palaeogeography. The first burst at the beginning of the Atdabanian was, perhaps, connected with the initiation of archaeocyathan expansion beyond the Siberian Platform. During the second half of the Atdabanian, closely related archaeocyathan assemblages were established from North Africa to Australia because neither climate, nor geographic isolation could have affected their differentiation in that time. At the end of the Atdabanian and the beginning of the Botomian the number of archaeocyathan genera again increased sharply, and isolated provinces were established. The American?Koryakiyan province was formed in western North America (from Alaska to Sonora) and included the Koryakiya, while the Afro?Siberian?Antarctic province probably extended from North Africa and Western Europe to Siberia, Australia, and Antarctica. The main difference between the regular archaeocyathan assemblages lies in what skeletal elements filled the intervallum. There was a certain stability in the distribution of skeletal elements of high taxonomic rank and an interchangeability of elements of low taxonomic rank.

Cambrian trophic web guilds consist of 1/Primary producers: calcified and non calcified bacteria, phytoplankton (acritarchs) and dissolved organic matter and 2/Primary consumers: mainly filter/suspension-feeders, some carnivorous, probable deposit feeders and rare grazers; parasites can only be surmised. Trophic modes are illustrated by examples taken in the different Cambrian communities.

Die verwandtschaftliche Stellung der ausgestorbenen Archaeocyathiden läßt sich nur funktionsmorphologisch klären. Unter den beobachteten Trends entspricht (1) die Verengung der äußeren gegenüber den inneren Poren dem Bernoulli-Prinzip. Dagegen vermindern (2) auswärtsstrebende Skelettelemente, (3) deren Vereinigung nahe der Innenwand (Torus-artige Strukturen) und (4) die Verlagerung des lebenden Gewebes in obere Etagen die Reibung zwischen einmündenden Kanalströmungen. Damit wird der Oskularstrom verstärkt und Refiltration verringert. Dies alles weist auf choanosome Filtrierer, d. h. auf Schwämme, hin.

Besonderheiten der Taphonomie und des Körperbaus, sowie morphologische Übergänge zwischen „Medusen“ „Anneliden“ und „Arthropoden“ machen eine Deutung der Ediacara-Fossilien als Metazoen unmöglich. Nach Morphologie und Größe sowie durch ihre hohe spezifische Oberfläche und das Fehlen eines inneren Verdauungsapparates kann man sie dagegen gut mit Sarcodinen vergleichen, besonders mit deren plasmodialer Untergruppe, den Xenophyophoria. In diesem Fall wären die Vendobionten einzellig gewesen.

AbstractA new species of archaeocyath sponge, Dictyocyathus neptunensis, is described from the lower third of the Nelson Limestone of the Neptune Range, Antarctica. Based on the presence of the trilobites Nelsonia schesisand Amphoton oatesi, these strata are interpreted to be mid- to late middle Cambrian in age. D. neptunensisshows a branching, low integration modular form and a very simple skeletal type. Such an organization is predicted from known morphological trends within the early Cambrian Archaeocyatha. Specimens are not in life position, and probably form part of a storm deposit. The absence of Dictyocyathusfrom latest early Cambrian (Toyonian) strata worldwide suggests a convergent nature for this highly simplified skeletal type in archaeocyaths.

AbstractA synonymized nomenclature for calcified sponges (archaeocyaths, stromatoporoids, chaetetids, sphinctozoans and pharetronids) is here presented to enable comparison of suggested homologous structures.

Ultraviolet irradiation of peripheral blood in therapeutic doses corrects the immuno-suppressive effect of staphylococcal toxin. The main immunoregulatory effect of ultraviolet irradiation is associated with the production of endogenous immune transmitters by blood cells such as interleukin-1 and tumor necrosis factor. Ultraviolet irradiation increases the content of CD3+and CD4+lymphocytes and restores the natural killer activity. The last parameter is proposed as a convenient criterion of the efficiency of quantum hemotherapy.

The materials of the article illustrate the estimation of the energy loading of a metal friction element in the metal-electrolyte-polymer friction pair while forming various types of double electrical layers with the release of its thermal stabilization state. The energy loading of the contact spots of the microprotrusions of the friction pairs of braking devices depends to a large extent on the electrical, thermal and chemical fields that are of a different nature to an allowable temperature and are above the surface layers of the polymer patch. The latter is significantly influenced by double electrical layers that are formed at the boundaries of the phases "metal-metal", "metal-polymer", "metal-semiconductor", "semiconductor-semiconductor" and "metal-electrolyte". When two electrically conducting phases come into contact with electrothermomechanical friction, a difference in electrical potentials arises, which is due to the formation of a double electric layer, that is an asymmetric distribution of charged particles near the phase boundary. The structure of the double electric layer does not matter for the magnitude of the reversible electrode potential, which is determined by the variation of the isobaric-isothermal potential of the corresponding electrochemical reaction.

Description of 4 new genera and 3 families of archaeocyaths.