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The release of methane from crater sites following meteorite impact is a possible consequence of the thermal alteration of organic matter, or tapping of reservoired gas of biogenic or abiogenic origin. At least the latter is feasible on Mars. Methane and higher hydrocarbons are susceptible to polymerization and precipitation by radioactive minerals. Where such minerals are present in impact target

Owing to its diagenetic instability, aragonite is rare in the geological record and almost entirely absent from pre-carboniferous sedimentary rocks. The former presence of this mineral in older deposits has to be inferred from petrographic, chemical or isotopic proxies. Crystals of aragonite that formed around 4563 million years ago occur in carbonaceous chondrite meteorites, showing that under ce

The dating of terrestrial impact craters and impact glasses that exhibit high degrees of mineralogical complexity can be problematic. However, if the maximum potential of the terrestrial impact crater record is to be realized, accurate and precise ages for crater-forming events are critical. Here we report a high-precision 40Ar/39Ar age for the Dellen impact structure, Sweden. Previous radio-isoto

Mark Burchell and the organizers of an RAS Specialist Discussion Meeting in May 2012 argue, on the basis of the Stardust and Hayabusa missions, that collecting samples from asteroids and comets offers a potentially rich scientific return – and one that can be exploited for many years to come.

A novel approach to the synthesis of Mn-doped InSb nanowires is demonstrated in this work. We first report on the preparation of InSb nanowires without high temperature treatment. Indium nanowires are grown by glance angle deposition and then coated with a layer of Sb. Single crystalline InSb nanowires are obtained by annealing In/Sb nanostructures at 200 °C. Triple-layer In/Mn/Sb nanostructures a

Weather and climate conditions can have large impacts on the outcome of forest management operations: Suboptimal conditions can increase the amount of driving damage to forest ground caused by the heavy machines used for harvesting, forwarding and soil scarification. Planting of tree seedlings is commonly practised after clear cutting, and drought in summer or soil frost uplifting in autumn reduce

Purpose: Objective diagnosis of symptomatic urinary tract infections in patients prone to asymptomatic bacteriuria is compromised by local host responses that are already present and the positive urine culture. We investigated interleukin-6 as a biomarker for nonfebrile urinary tract infection severity and diagnostic thresholds for interleukin-6 and 8, and neutrophils to differentiate between asym

Research indicates that expert performance is domain specific and hardly transfers to novel tasks or domains. However, due to technological changes in dynamic work settings, experts sometimes need to adapt and transfer their skills to new task affordances. The present mixed method study investigates whether eye movement modeling examples (EMME) can promote adaptive expertise in medical image diagn

Essentials: Research suggests that intensive treatment episodes may increase the risk to develop inhibitors. We performed an international nested case-control study with 298 non-severe hemophilia A patients. Surgery and a high dose of factor VIII concentrate were associated with increased inhibitor risk. Physicians need to review arguments for factor VIII dose and elective surgery extra critically

Surface deterioration of concrete occurs at the waterline of many hydraulic structures in contact with soft water in cold regions. Progressive disintegration of the surface leads to exposure of the coarse aggregate and ultimately of the reinforcing steel. Mechanical, physical and chemical processes could cause deterioration of concrete at the waterline. The objective of this study was to investiga

Since the EU introduced the European Landscape Convention (ELC) in 2000, the landscape has received growing attention in spatial planning and environmental impact assessments. To promote implementation of the ELC, the Swedish National Heritage Board proposed its Landscape Vision 2020, which addresses the goal of a ‘holistic landscape policy’. This study examined challenges and benefits brought by

Complement-mediated atypical hemolytic uremic syndrome (aHUS) is a rare disease associated with high mortality and morbidity. Renal biopsies often indicate thrombotic microangiopathy (TMA). The condition is caused by an excessive activation of the alternative pathway leading to depositions of membrane attack complexes (MAC) on host cells. It may depend on mutations in complement components and reg

To address increasing climatic variability and extremes, cities are gradually forced to develop climate change adaptation strategies that can ensure a continuous and transformative adaptation process. There is widespread consensus that the sustainable establishment of such strategies requires transdisciplinary approaches, that is, the involvement of internal and external stakeholders (state, civil

The aim of this paper is to explore, illustrate and conceptualise how the introduction of mobile phones transforms the practice of shopping. Drawing on a focus group study of young adults and making use of Practice Theory, this paper shows that the introduction of mobile phones reconfigures the practice of shopping subsequently transforming the agency of consumers. Mobile phones enable consumers t

Striatal neurons forming the indirect pathway (iSPNs) are particularly vulnerable in Huntington's disease (HD). In this study we set out to investigate morphological and physiological alterations of iSPNs in two mouse models of HD with relatively slow disease progression (long CAG repeat R6/2 and zQ175-KI). Both were crossed with a transgenic mouse line expressing eGFP in iSPNs. Using the open-fie

Background Oxidative stress and inflammation exacerbate tissue damage in the brain after ischemic stroke. Dimethyl-fumarate (DMF) and its metabolite monomethyl-fumarate (MMF) are known to stimulate anti-oxidant pathways and modulate inflammatory responses. Considering these dual effects of fumarates, we examined the effect of MMF treatment after ischemic stroke in mice. Methods Permanent middle ce

Background: Occurrence of severe asthma exacerbations are the cornerstone of the evaluation of asthma management, but severe asthma exacerbations are rare events. Therefore, trials that assess drug efficacy on exacerbations are done late in clinical development programmes. We aimed to establish an endpoint capturing clinically relevant deteriorations (diary events) that, when combined with severe

This article solves the problem of how to obtain a zero-order hold sampled version of a state space system containing several time delays at arbitrary positions. No assumption is made on commensurability of the time delays. It is shown that the condition for obtaining a finite dimensional sampled system for all sampling periods is that there are 'no signal loops' around any of the time delays. A s