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The oxygen isotopic compositions of calcite grains in four CM carbonaceous chondrites have been determined by NanoSIMS, and results reveal that aqueous solutions evolved in a similar manner between parent body regions with different intensities of aqueous alteration. Two types of calcite were identified in Murchison, Mighei, Cold Bokkeveld and LaPaz Icefield 031166 by differences in their petrogra

The local geology at Kloxåsen is characterised by ejecta deposits from the 458 Ma Lockne marine impact. The Kloxåsen ejecta are located on a Caledonian parautochthonous unit, approximately 7 km from the centre of the 7.5-km-wide Lockne crater structure. The ejecta were deposited on the seafloor and were covered with seawater immediately after the impact event. Of special interest is a mafic impact

The highly eroded 23 km diameter Rochechouart impact structure, France, has extensive evidence for post-impact hydrothermal alteration and sulphide mineralisation. The sulphides can be divided into four types on the basis of their mineralogy and host rock. They range from pyrites and chalcopyrite in the underlying coherent crystalline basement to pyrites hosted in the impactites. Sulphur isotopic

Elephant Moraine (EET) 96029 is a CM carbonaceous chondrite regolith breccia with evidence for unusually mild aqueous alteration, a later phase of heating and terrestrial weathering. The presence of phyllosilicates and carbonates within chondrules and the fine-grained matrix indicates that this meteorite was aqueously altered in its parent body. Features showing that water-mediated processing was

Granites aged 1.9. Ga to 1.5. Ga exhibit molybdenite mineralization globally. Sandstones deposited during the mid-Proterozoic have a provenance dominated by 1.9-1.7. Ga basement. The mid-Proterozoic surface environment was, consequently, receiving detritus from the molybdenum-rich granites. Thus there was a supply of molybdenum available in terrestrial or shallow marine environments at a time when

Forsterite and clinoenstatite in type IAB chondrules from the Murchison CM carbonaceous chondrite have been partially serpentinized, and the mechanisms of their alteration reveal crystallographic and microstructural controls on the reaction of silicate minerals with parent body aqueous solutions. Grains of forsterite were altered in two stages. Narrow veinlets of Fe-rich serpentine formed first an

There is extensive evidence for the microbial colonization of seafloor basalts in the modern ocean and in the geological record. The sulfur isotope composition of pyrite in the basalts commonly indicates marked isotopic fractionation due to microbial sulfate reduction. Sections through the Nemagraptus gracilis zone (Ordovician) in Great Britain and Ireland are characterized by both widespread pill

Petrographic analysis of eight CM carbonaceous chondrites (EET 96029, LAP 031166, LON 94101, MET 01072, Murchison, Murray, SCO 06043, QUE 93005) by electron imaging and diffraction, and X-ray computed tomography, reveals that six of them have a petrofabric defined by shock flattened chondrules. With the exception of Murchison, those CMs that have a strong petrofabric also contain open or mineraliz

Carbonate minerals in CM carbonaceous chondrite meteorites, along with the silicates and sulphides with which they are intergrown, provide a detailed record of the nature and evolution of parent body porosity and permeability, and the chemical composition, temperature and longevity of aqueous solutions. Fourteen meteorites were studied that range in petrologic subtype from mildly aqueously altered

Calcite twinning in carbonaceous chondrite meteorites can be used to reconstruct the deformation history and the parent body environment during and/or after aqueous alteration, but the shock pressure threshold at which the twins develop is unknown. Accordingly, the aim of this study is to determine the magnitude of shock pressure that is needed to generate calcite twins. This was done by measuring

The CM2 carbonaceous chondrite LON 94101 contains aragonite and two generations of calcite that provide snapshots of the chemical and isotopic evolution of aqueous solutions during parent body alteration. Aragonite was the first carbonate to crystallize. It is rare, heterogeneously distributed within the meteorite matrix, and its mean oxygen isotope values are δ18O 39.9±0.6‰, δ17O -0.3±1.0‰ (1σ).

Clasts in the CM2 carbonaceous chondrite Lonewolf Nunataks (LON) 94101 have been characterized using scanning and transmission electron microscopy and electron microprobe analysis to determine their degrees of aqueous alteration, and the timing of alteration relative to incorporation of clasts into the host. The provenance of the clasts, and the mechanism by which they were incorporated and mixed

Meteorite impacts, one of the most ubiquitous processes in the solar system, have the ability to destroy as well as create habitats for life. The impact process can increase the translucency and porosity of the target substrate, as well as mobilize biologically relevant elements within the substrate. For endolithic organisms, this process has important implications, especially in extreme environme

The Antarctic CM2 carbonaceous chondrite QUE 93005 contains four compositionally distinct carbonates, namely breunnerite, calcite, dolomite and a Ca-poor dolomite. These carbonates can form monomineralic grains, or may be intergrown as bimineralic grains consisting of dolomite plus breunnerite and dolomite plus calcite, or polymineralic grains containing an intergrowth of breunnerite, Ca-poor dolo

Background: Brief Admission is a crisis and risk management strategy in which self-harming and suicidal individuals with three or more diagnostic criteria of borderline personality disorder self-admit to hospital at times of increasing risk when other efforts to stay safe are failing. Standardized in the current randomized controlled trial, the intensity of Brief Admission Skåne is implemented in

A complex reaction mechanism of oxidation of the anti-tubercular prodrug isoniazid (isonicotinic hydrazide, INH) by [IrCl6]2− as a model for redox processes of such drugs in biological systems has been studied in aqueous solution as a function of pH between 0 and 8.5. Similar experiments have been performed with its isomer nicotinic hydrazide (NH). All reactions are overall second-order, first-ordA complex reaction mechanism of oxidation of the anti-tubercular prodrug isoniazid (isonicotinic hydrazide, INH) by [IrCl6]2− as a model for redox processes of such drugs in biological systems has been studied in aqueous solution as a function of pH between 0 and 8.5. Similar experiments have been performed with its isomer nicotinic hydrazide (NH). All reactions are overall second-order, first-ord

Årsredovisningar handlar inte bara om att kommunicera ett företags resultat och finansiella ställning utan även om att att upprätthålla förtroendet för finansmarknaden och kapitalismen. De fungerar mer som en ritual än som allsidig information, skriver forskarna Henrik Rahm och Peter Svensson.

BackgroundThe aim of this study was to investigate plasma levels of sST2 and sCD163 to determine whether they at an early stage could predict development of diabetic nephropathy and/or diabetic retinopathy in patients at clinical onset.MethodsPatients diagnosed with diabetes mellitus at age 15–34 years between 1987 and 1988 (n = 220) were included. Data such as BMI, smoking, HbA1c and islet cell a

Background Obesity is linked to cardiovascular diseases and increasingly common in type 1 diabetes mellitus (T1DM) since the introduction of intensified insulin therapy. Our main aim was to explore associations between obesity and depression, anxiety, alexithymia and self-image measures and to control for lifestyle variables in a sample of persons with T1DM. Secondary aims were to explore associat