A palaeoenvironmental reconstruction of the Middle Jurassic of Sardinia (Italy) based on integrated palaeobotanical, palynological and lithofacies data assessment

During the Jurassic, Sardinia was close to continental Europe. Emerged lands started from a single island forming in time a progressively sinking archipelago. This complex palaeogeographic situation gave origin to a diverse landscape with a variety of habitats. Collection- and literature-based palaeobotanical, palynological and lithofacies studies were carried out on the Genna Selole Formation for palaeoenvironmental interpretations. They evidence a generally warm and humid climate, affected occasionally by drier periods. Several distinct ecosystems can be discerned in this climate, including alluvial fans with braided streams (Laconi-Gadoni lithofacies), paralic swamps and coasts (Nurri-Escalaplano lithofacies), and lagoons and shallow marine environments (Ussassai-Perdasdefogu lithofacies). The non-marine environments were covered by extensive lowland and a reduced coastal and tidally influenced environment. Both the river and the upland/hinterland environments are of limited impact for the reconstruction. The difference between the composition of the palynological and palaeobotanical associations evidence the discrepancies obtained using only one of those proxies. The macroremains reflect the local palaeoenvironments better, although subjected to a transport bias (e.g. missing upland elements and delicate organs), whereas the palynomorphs permit to reconstruct the regional palaeoclimate. Considering that the flora of Sardinia is the southernmost of all Middle Jurassic European floras, this multidisciplinary study increases our understanding of the terrestrial environments during that period of time

Light-Induced Responses of Slow Oscillatory Neurons of the Rat Olivary Pretectal Nucleus

Background: The olivary pretectal nucleus (OPN) is a small midbrain structure responsible for pupil constriction in response to eye illumination. Previous electrophysiological studies have shown that OPN neurons code light intensity levels and therefore are called luminance detectors. Recently, we described an additional population of OPN neurons, characterized by a slow rhythmic pattern of action potentials in light-on conditions. Rhythmic patterns generated by these cells last for a period of approximately 2 minutes. Methodology: To answer whether oscillatory OPN cells are light responsive and whether oscillatory activity depends on retinal afferents, we performed in vivo electrophysiology experiments on urethane anaesthetized Wistar rats. Extracellular recordings were combined with changes in light conditions (light-dark-light transitions), brief light stimulations of the contralateral eye (diverse illuminances) or intraocular injections of tetrodotoxin (TTX). Conclusions: We found that oscillatory neurons were able to fire rhythmically in darkness and were responsive to eye illumination in a manner resembling that of luminance detectors. Their firing rate increased together with the strength of the light stimulation. In addition, during the train of light pulses, we observed two profiles of responses: oscillationpreserving and oscillation-disrupting, which occurred during low- and high-illuminance stimuli presentation respectively. Moreover, we have shown that contralateral retina inactivation eliminated oscillation and significantly reduced the firin

Українська жіноча література кінця XIX - початку XX століття та тема жінки у творчості Галини Комарівни

At the end of the XIX and the beginning of the XX century the Ukrainian nation makes more and more courageous steps to the full-valued life which helps to promote the development of the women’s consciousness. National and women’s problems are the main topics (in the creative works of women – members of the feminist movement, as women can be free only being independent) in an independent and free country. With her creative work Halyna Komarivna made a great contribution into the development of Ukrainian literature. Women’s theme became the most important in her creativity

New data about Matonia braunii (Göppert) Harris from the Early Jurassic of Poland and its ecology

Fern remains of matoniacean affinity were found in the Lower Hettangian strata of lacustrine/backswamp origin from the Niekłań PGI 1 borehole (central Poland, Holy Cross Mts.). The preserved fragments have been identified as Matonia braunii (Göppert, 1841) Harris, 1980. The remains suggest a rather small, low-growth plant with palmately compound fronds. The sori contain at least 5 sporangia preserved with well-developed annuli. The spores are triangular, trilete and kyrtomate, with a thin and smooth surface corresponding with dispersed Dictyophyllidites mortoni (de Jersey, 1959) Playford et Dettmann, 1965. Based on the gross morphology of sterile and fertile pinnae, suggestions made by Harris (1980) on the synonymy of Phlebopteris braunii (Göppert, 1841) Hirmer et Hörhammer, 1936 with P. muensteri Schenk, 1867 (Hirmer and Hörhammer, 1936) and their referral to Matonia braunii is proved and confirmed in this paper. The fern occurs in strata indicating a warm and humid climate and approaching transgression resulting in a high water table and the enhanced accumulation of organic matter

Pteruchus (microsporophyll): part 2 of a reassessment of Gondwana Triassic plant genera and a reclassification of some previously attributed

The microsporophyll genus Pteruchus, belonging to the pteridosperms (seed ferns) in the family Umkomasiaceae (Corystospermaceae), is reassessed comprehensively worldwide and emended. All records are analysed, and some fertile structures previously attributed are reclassified. The Lower Jurassic record of Pteruchus from Germany is ascribed to a new genus as Muelkirchium septentrionalis. Pteruchus is shown to be restricted to the Triassic of Gondwana and is clearly affiliated with the megasporophyll genus Umkomasia and the vegetative leaf genus Dicroidium. It is well represented from Argentina, Antarctica, Australia and southern Africa; the Molteno Formation of southern Africa is by far the most comprehensively sampled, yielding three species and 425 specimens from 22 localities. Nomenclatural problems with the species of Pteruchus are addressed. A key to Pteruchus species is provided; geographic and stratigraphic distributions are tabulated