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The 39-2Ma Haughton impact structure on Devon Island comprises a thick target succession of sedimentary rocks, mainly carbonates. The carbonates contain pre-impact organic matter, including fossil biological markers. Haughton is located in an area where no major thermal event has affected the sedimentary succession after heating caused by impact. This makes Haughton uniquely suitable for studies c

In a series of experiments the pyrolytic effects of the heating induced during the hypervelocity impact (HVI) of small projectiles of high TOC mudrock were observed. Impacts at these high speeds (km s-1) release sufficient energy to vaporise metal projectiles, and the temperatures created greatly exceed the pyrolysis temperatures typically employed during laboratory studies of the thermal alterati

The Ordovician Lockne impact structure is located in central Sweden. The target lithology consisted of limestone and black unconsolidated shale overlaying a Precambrian crystalline basement. The Precambrian basement is uranium-rich, and the black shale is both uranium- and organic-rich. This circumstance makes Lockne a good candidate for testing the occurrence of U-Th-rich bitumen nodules in an im

Melt fragments in melt breccias from the Gardnos impact crater, Norway, contain abundant carbon. A high proportion of the carbon present in the original melt was preserved. The stripping of hydrogen from carbon during melting prevents later hydrocarbon formation, hence the carbon is fixed in place rather than volatilized. Underlying lithic breccias that were not melted record hydrocarbon generatio

The response of organic matter to high-temperature events is important to astrobiology, as it governs the survival of carbon during several processes that may be critical to the origin and spread of life. Impact cratering is a widespread high-temperature process. The behaviour of carbon during impact events is not well understood. But there is the potential to examine other examples of the respons

Graphitic carbon is a widespread precipitate in terrestrial and extraterrestrial samples. However it has a range of possible origins, which can be difficult to distinguish, including the in situ alteration of organic matter, thermal alteration of hydrocarbons, and precipitation from C-O-H fluids. Petrographic characteristics help to understand the origin of the graphite, including relationships wi

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