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The recovery of marine ecosystems following a mass extinction event involves an extended interval of increasing biotic diversity and ecosystem complexity. The pace of recovery may be controlled by intrinsic ecosystem or extrinsic environmental factors. Here, we present an analysis of changes in marine conditions following the end-Permian mass extinction with the objective of evaluating the role of

This paper is dedicated to a global correlation of marine Permian-Triassic boundary layers on the basis of partially published and original data on the δ13Corg and δ13Ccarb values of the Suol section (Setorym River, South Verkhoyansk region). The section consists of six carbon isotopic intervals, which are easily distinguishable in the carbon isotopic curves for a series of Permian-Triassic refere

The Kuh e Dena sedimentary section in Iran developed on the southwestern margin of the Neotethys Ocean. The fossil- and bioturbation-lean Early Triassic section (Late Dienerian to Early Smithian) is typified by finely laminated calcareous shales that are interbedded with laterally extending carbonate beds, which are mostly composed of calyx-shaped carbonate crystal fans. The calyxes consist of fib

The global carbon cycle experienced a major perturbation during the Permian-Triassic transition, reflected inter alia in a large increase in the vertical (shallow-to-deep) gradient of carbonate δ13C (δ13Ccarb) in Early Triassic seas. However, the effect of this perturbation on the vertical gradient of organic matter δ13C in seawater (δ13Corg) is less known to date. Here, we examine geographic and

The Global Stratotype Section and Point (GSSP) defining the base of the Jurassic System Lower Jurassic Epoch and Hettangian Stage is situated at the Kuhjoch pass, Karwendel Mountains, Northern Calcareous Alps, Austria (47°29'02"N/11°31'50"E). The Triassic-Jurassic (T-J) boundary is exposed at Kuhjoch West and at Kuhjoch East, and corresponds to the first occurrence (FO) of the ammonite Psiloceras

Final recovery of marine ecosystems after the end-Permian mass extinction took several million years, partly due to inhospitable environments and three episodes of further extinction that occurred during the Early Triassic: in the late Griesbachian, near the Smithian-Spathian boundary (SSB), and in the late Spathian. The SSB crisis coincides with an episode of extreme warmth, but has been little s

New calcareous nannofossil analyses from the Northern Calcareous Alps of Austria are herein used to update and improve the state of knowledge about the oldest occurrence of coccolithophores reported in the literature. Previously reported Norian occurrences of coccoliths were based on an obsolete Triassic chronostratigraphy, in which the Rhaetian stage was subsumed into the Norian ('Sevatian 2'). T

The end-Triassic mass extinction (c. 201.6 Ma) was one of the five largest mass-extinction events in the history of animal life. It was also associated with a dramatic, long-lasting change in sedimentation style along the margins of the Tethys Ocean, from generally organic-matter-poor sediments during the Triassic to generally organic-matter-rich black shales during the Jurassic. New core material

A new carbon isotope record with conodont biostratigraphy is presented for the entire Early Triassic from the Musandam Peninsula, United Arab Emirates (UAE). This is a near-continuous and exclusively shallow marine carbonate succession that allows analysis of a high-resolution primary carbon cycling signature in the absence of significant depth-dependent or lithologic controls. The Musandam carbon

Saturated pool boiling heat transfer of water is investigated experimentally on copper surfaces with nanoparticle coatings at atmospheric pressure. The coatings are generated by an electrophoretic deposition method (EPD). Three modified surfaces are prepared with gold nanoparticles of 0.20 mg, 0.25 mg and 0.30 mg, respectively. During the deposition, ethanol works as the solvent while the electri

Profound changes in both marine and terrestrial biota during the end-Triassic mass extinction event and associated successive carbon cycle perturbations across the Triassic-Jurassic boundary (T-J, 201.3 Ma) have primarily been attributed to volcanic emissions from the Central Atlantic Magmatic Province and/or injection of methane. Here we present a new extended organic carbon isotope record from a

The evolution of complex life over the past 600 million years was disrupted by at least five mass extinctions, one of which occurred at the close of the Triassic period. The end-Triassic extinction corresponds to a period of high atmospheric-CO 2 concentrations caused by massive volcanism and biomass burning; most extinction scenarios invoke the resulting environmental perturbations in accounting

The bryopsidalean alga Halimeda gained an important role as carbonate producer in Cenozoic tropical coral reefs and became a significant constituent of the modern Mediterranean seaweed flora. There are, however, open questions at which time the thermophile alga appeared in the cooler Mediterranean Sea and why it is not detected in coral reefs of the modern Persian Gulf. To unravel the biogeography

The Middle Permian to Lower Triassic Buday'ah section, exposed in the Oman Mountains, is the first deep-sea section to be described in the Neotethys. The oceanic sediments were deposited along the southern Tethys margin in the newly formed Hawasina Basin. It is one of the few places where true Tethyan Permian radiolarites are exposed that allow the documentation of CCD evolution through time. The

Background: The long-term effect of distal radial fracture malunion on activity limitations is unknown. Between 2001 and 2002, we conducted a prospective cohort study of all patients with distal radial fracture treated with casting or percutaneous fixation in northeast Scania in Sweden. In that original study, the patients completed the Disabilities of the Arm, Shoulder and Hand (DASH) questionnai

In recent years, machine learning has evolved in a fast pace as both algorithms and computing power are constantly improving. In this study, a machine learning model for predicting the fuel oil consumption from engine data has been developed for a cruise ship operating in the Baltic Sea. The cruise ship is equipped with legacy volume flow meters and newly installed mass flow meters, as well as an

In the design of boiler furnaces and gas turbine combustors it is desirable to enable prediction of the radiative heat transfer with high accuracy so that the heat loads on the walls can be properly estimated. In such applications commonly participating media like various gases and particles, e.g., soot, need to be taken into account. Then in addition to the common governing equations for conserva

In this study, steady-state laminar natural convection of Cu and TiO 2 nanofluids inside different enclosures is numerically investigated. Natural convection is concerned due to a temperature difference between the hot and cold surfaces. The Boussinesq approximation is used to form the governing equations and the commercial software package ANSYS Fluent version 14.0 is used to numerically solve

A Dimple Jacket Heat Exchanger (DJHE) is designed for the Chemical Post-Processing Integrated Equipment (CPPIE) to enhance the heat transfer performance during chemical reaction, crystallization and drying processes. In this paper, a 3D model of a DJHE is established. Dynamic variation of temperature inside the DJHE is compared with experimental data to validate the accuracy of the numerical metho

Accurate quantitation of activity provides the basis for internal dosimetry of targeted radionuclide therapies. This study investigated quantitative imaging capabilities at sites with a variety of experience and equipment and assessed levels of errors in activity quantitation in Single-Photon Emission Computed Tomography (SPECT) and planar imaging. Participants from 9 countries took part in a comp