152 research outputs found

    Proceedings of a Workshop on Antarctic Meteorite Stranding Surfaces

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    The discovery of large numbers of meteorites on the Antarctic Ice Sheet is one of the most exciting developments in polar science in recent years. The meteorites are found on areas of ice called stranding surfaces. Because of the sudden availability of hundreds, and then thousands, of new meteorite specimens at these sites, the significance of the discovery of meteorite stranding surfaces in Antarctica had an immediate and profound impact on planetary science, but there is also in this discovery an enormous, largely unrealized potential to glaciology for records of climatic and ice sheet changes. The glaciological interest derives from the antiquity of the ice in meteorite stranding surfaces. This exposed ice covers a range of ages, probably between zero and more than 500,000 years. The Workshop on Antarctic Meteorite Stranding Surfaces was convened to explore this potential and to devise a course of action that could be recommended to granting agencies. The workshop recognized three prime functions of meteorite stranding surfaces. They provide: (1) A proxy record of climatic change (i.e., a long record of climatic change is probably preserved in the exposed ice stratigraphy); (2) A proxy record of ice volume change; and (3) A source of unique nonterrestrial material

    Techniques for Restoration of Disturbed Coastal Wetlands of the Great Lakes

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    A long history of human-induced degradation of Great Lakes wetlands has made restoration a necessity, but the practice of wetland restoration is relatively new, especially in large lake systems. Therefore, we compiled tested methods and developed additional potential methods based on scientific understanding of Great Lakes wetland ecosystems to provide an overview of approaches fur restoration. We addressed this challenge by focusing on four general fields of science: hydrology, sedimentology, chemistry, and biology. Hydrologic remediation methods include restoring hydrologic connections between diked and hydrologically altered wetlands and the lakes, restoring water tables lowered by ditching, and restoring natural variation in lake levels of regulated lakes Superior and Ontario. Sedimentological remediation methods include management of sediment input from uplands, removal or proper management of dams on tributary rivers. and restoration of protective barrier beaches and sand spits. Chemical remediation methods include reducing or eliminating inputs of contaminants from point and non-point sources, natural sediment remediation by biodegradation and chemical degradation, and active sediment remediation by removal or by in situ treatment. Biological remediation methods include control of non-target organisms, enhancing populations of target organisms, and enhancing habitat for target organisms. Some of these methods were used in three major restoration projects (Metzger Marsh on Lake Erie and Cootes Paradise and Oshawa Second Marsh on Lake Ontario). which are described as case studies to show practical applications of wetland restoration in the Great Lakes. Successful restoration techniques that do not require continued manipulation must be founded in the basic tenets of ecology and should mimic natural processes. Success is demonstrated by the sustainability, productivity, nutrient-retention ability, invasibility, and biotic interactions within a restored wetland

    Signing at the beginning versus at the end does not decrease dishonesty

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    Honest reporting is essential for society to function well. However, people frequently lie when asked to provide information, such as misrepresenting their income to save money on taxes. A landmark finding published in PNAS [L. L. Shu, N. Mazar, F. Gino, D. Ariely, M. H. Bazerman, *Proc. Natl. Acad. Sci. USA.* 109, 15197–15200 (2012)] provided evidence for a simple way of encouraging honest reporting: asking people to sign a veracity statement at the beginning instead of at the end of a self-report form. Since this finding was published, various government agencies have adopted this practice. However, in this project, we failed to replicate this result. Across five conceptual replications (*n* = 4,559) and one highly powered, preregistered, direct replication (*n* = 1,235) conducted with the authors of the original paper, we observed no effect of signing first on honest reporting. Given the policy applications of this result, it is important to update the scientific record regarding the veracity of these results

    The neurological consequences of contracting covid-19

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    Since the first confirmed case in Wuhan, China on December 31, 2019, the novel coronavirus (SARS-CoV-2) has spread quickly, infecting 165 million people as of May 2021. Since this first detection, research has indicated that people contracting the virus may suffer neurological and mental disorders and deficits, in addition to the respiratory and other organ challenges caused by COVID-19. Specifically, early evidence suggests that COVID-19 has both mild (e.g., loss of smell (anosmia), loss of taste (ageusia), latent blinks (hete-rophila), headaches, dizziness, confusion) and more severe outcomes (e.g., cognitive impairments, seizures, delirium, psychosis, strokes). Longer-term neurological challenges or damage may also occur. This knowledge should inform clinical guidelines, assessment, and public health planning while more systematic research using biological, clinical, and longitudinal methods provides further insights

    Ice-stream stability on a reverse bed slope

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    Marine-based ice streams whose beds deepen inland are thought to be inherently unstable. This instability is of particular concern because significant portions of the marine-based West Antarctic and Greenland ice sheets are losing mass and their retreat could contribute significantly to future sea-level rise. However, the present understanding of ice-stream stability is limited by observational records that are too short to resolve multi-decadal to millennial-scale behaviour or to validate numerical models8. Here we present a dynamic numerical simulation of Antarctic ice-stream retreat since the Last Glacial Maximum (LGM), constrained by geophysical data, whose behaviour is consistent with the geomorphological record. We find that retreat of Marguerite Bay Ice Stream following the LGM was highly nonlinear and was interrupted by stabilizations on a reverse-sloping bed, where theory predicts rapid unstable retreat. We demonstrate that these transient stabilizations were caused by enhanced lateral drag as the ice stream narrowed. We conclude that, as well as bed topography, ice-stream width and long-term retreat history are crucial for understanding decadal- to centennial-scale ice-stream behaviour and marine ice-sheet vulnerability

    North-east sector of the Greenland Ice Sheet to undergo the greatest inland expansion of supraglacial lakes during the 21st century

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    The formation and rapid drainage of supraglacial lakes (SGL) influences the mass balance and dynamics of the Greenland Ice Sheet (GrIS). Although SGLs are expected to spread inland during the 21st century due to atmospheric warming, less is known about their future spatial distribution and volume. We use GrIS surface elevation model and regional climate model outputs to show that at the end of the 21st century (2070-2099) approximately 9.8 ± 3.9 km3 (+113% compared to 1980-2009) and 12.6 ± 5 km3 (+174%) of meltwater could be stored in SGLs under moderate (RCP 4.5) and high (RCP 8.5) climate change scenarios respectively. The largest increase is expected in the north-eastern sector of the GrIS (191% in RCP 4.5 and 320% in RCP 8.5), whereas in west Greenland, where the most SGLs are currently observed, the future increase will be relatively moderate (55% in RCP 4.5 and 68% in RCP 8.5)

    Happy to help? A systematic review and meta-analysis of the effects of performing acts of kindness on the well-being of the actor

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    © 2018 The Authors. Do acts of kindness improve the well-being of the actor? Recent advances in the behavioural sciences have provided a number of explanations of human social, cooperative and altruistic behaviour. These theories predict that people will be ‘happy to help’ family, friends, community members, spouses, and even strangers under some conditions. Here we conduct a systematic review and meta-analysis of the experimental evidence that kindness interventions (for example, performing ‘random acts of kindness’) boost subjective well-being. Our initial search of the literature identified 489 articles; of which 24 (27 studies) met the inclusion criteria (total N = 4045). These 27 studies, some of which included multiple control conditions and dependent measures, yielded 52 effect sizes. Multi-level modeling revealed that the overall effect of kindness on the well-being of the actor is small-to-medium (δ = 0.28). The effect was not moderated by sex, age, type of participant, intervention, control condition or outcome measure. There was no indication of publication bias. We discuss the limitations of the current literature, and recommend that future research test more specific theories of kindness: taking kindness-specific individual differences into account; distinguishing between the effects of kindness to specific categories of people; and considering a wider range of proximal and distal outcomes. Such research will advance our understanding of the causes and consequences of kindness, and help practitioners to maximise the effectiveness of kindness interventions to improve well-being
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