The Tectono-Magmatic Evolution of the Taimyr Peninsula: Further Constraints from New Ion-Microprobe Data

ern Connection of the Uralides Summary: We present the initial results of a V-Th-Pb zircon ion-microprobe investigation on samples frorn the Central Belt ofTaimyr, in order to constrain its tcctono-magmatic evolution. The zircon samples are from a defonned two-mica granite (Faddey Massif), deforrncd metarnorphosed gabbroic e1ike entraineel as pods anel lenses within metamorphoscd tholeiitic basalts of thc Kunar-Mod volcanic suite (Klyazrna River region), a metamorphoscd rhyolite ofthe samc volcanic suite overlying the basic metavolcanic rocks, as weil as an undefonned dolerite dike which intrudes the metamorphoscd Kunar-Mod basic volcanic rocks. Preliminary results on zircons from the two-mica granitc suggest a crystallization age of.-..630 Ma for this rock, with inheritance frorn assimilated crust 840 Ma to 1.1 Ga in age. In the Klyazrna River region, zircons from the meta-rhyolite yielel a concordant age of.-..630 Ma. Zircons frorn the entrained metagabbroic dikes have so far yielded an age of.-..615 Ma (1 grain), as weil as Archean age

Actual Aspects of Medical Application of Black Nut – Juglans Nigra L. (Review)

Introduction. Herbal drugs of black walnut (Juglans nigra L.) are not registered on the territory of the Russian Federation at the present time. However, the State Register of Medicinal Products includes an extract of unripe fruits of a related species walnut (Juglans regia L.) «Yuglanex» (made in Russia) and the complex herbal drug «Tonsilgon» (made in Germany). A number of biologically active food supplements from black walnut raw materials have been registered by Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing. They are an additional source of phenolic compounds as tannins and flavonoids. The purpose of the article is to study and systematize up-to-date information on the chemical composition of the medicinal plant raw material of black walnut and the pharmacological properties of its main biologically active compounds.Text. All parts of the black walnut are used in the ethnomedicine of the indigenous population of North America according to indications similar to the walnut in Asia and the Manchurian nut in the Far East: snake bites, fever and disorders of the gastrointestinal tract.The chemical composition of the medicinal plant raw material of black walnut is dencently walnut by its qualitative composition. Fruits, bark and leaves of black walnut contain a rich polyphenol complex (naphthoquinones, in particular, juglon and its derivatives, tannins, flavonoids, phenolic acids), vitamins, essential oil, organic acids. However, the quantitative analysis revealed a higher content of biologically active substances in the raw black walnut, especially in relation to polyphenolic compounds.The scientific literature describes the results of experiments on animals, confirming antioxidant, antimicrobial, antifungal, antiviral, antiparasitic, hypoglycemic, antispasmodic, and anti-tumor effect on certain cell lines.Conclusion. As a result of studying the literature and systematizing the current information on the chemical composition of the medicinal plant raw material of the black nut and the pharmacological properties of its main biologically active compounds, it has been established that the main properties are related to the presence of the phenol complex. However, a deeper study of the chemical composition is required. Both the total extracts of the black walnut from plant raw materials and individual compounds show predominantly antimicrobial, antifungal, antioxidant, antiviral, hypotensive, immunomodulatory, antitumor and antispasmodic activities in preclinical trials

First paleomagnetic data for the New Siberian Islands: Implications for Arctic paleogeography

In this paper we present new paleomagnetic and paleontological data from the Ordovician and Silurian carbonate rocks of Kotelny Island (the Anjou Archipelago), and from the Ordovician turbidities of Bennett Island (the De Long Archipelago). It is assumed that both archipelagos belong to the NSI (New Siberian Islands) terrane — a key tectonic element in the Arctic region. Ages of the studied rocks have been established by paleontological data and lithological correlations. Our new data on conodonts combined with those from previous studies of Ordovician and Silurian fauna indicate a biogeographic similarity between the shelves of the Siberian paleocontinent and the NSI in the Early Paleozoic. Three new paleomagnetic poles for the NSI (48.9°N, 13.8°E, A95 = 18.1° for 475 Ma; 45.5°N, 31.9°E, A95 = 11.0° for 465 Ma, and 33.7°N, 55.7°E, A95 = 11.0° for 435 Ma) fall between the south-eastern part of Central Europe and the Zagros Mountains. The similarity of paleomagnetic directions from Kotelny and Bennet islands confirms that both the Anjou and De Long archipelagos belong to the same terrane. Calculated paleolatitudes indicate that in Ordovician–Silurian times this terrane has been located between 30° and 45°, possibly in the northern hemisphere. Based on this observation, we suggest a linkage between the NSI and the Kolyma–Omolon superterrane. Comparison of apparent polar wander paths (APWPs) of the NSI, Siberia and other cratons/terranes suggests that the NSI drifted independently. We demonstrate that the structural line between Svyatoy Nos Peninsula and Great Lyakhovsky Island is the continuation of the Kolyma Loop suture on the Arctic shelf, and expect that the continuation of the South Anyui suture is to be found east of the NSI