The evolution of sedimentary systems on Mars, and implications for climate in the Hesperian-Amazonian epochs

Alluvial deposits within Martian impact craters are sensitive morphologic records of modification by liquid water, and can help constrain past climate conditions. This study explores the evolution of Late Hesperian-Amazonian-age sedimentary deposits within two craters, Mojave and Eberswalde. For Mojave crater, the evolution of intracrater alluvial fan systems and the climatic context are poorly understood. Analysis of stratigraphic relationships between the fans and crater infill suggests that precipitation which formed the systems was temporally closely associated with the impact process. Regional mapping of youthful fluvial features within a ~300 km radius of Mojave supports a genetic link between the impact event and precipitation, due to dense clustering around the crater. Analysis of five additional Late Hesperian-Amazonian craters, which also contain evidence for catchment-fan formation by precipitation, shows similar clustering of fluvial activity. Two mechanisms of water production are suggested to have formed the features observed: (a) localised impact-induced precipitation due to impact plume-related atmospheric effects, and (b) a regional snowpack which melted locally due to impact-induced heating. Eberswalde crater contains multiple sedimentary systems sourced from channels which breach the crater rim, and the depositional system as a whole is poorly understood. Mapping of rocks with differing characteristics within the second largest depositional system, and reconstruction of stratigraphic architecture, shows that the deposit records backstepping of putative deltaic lobe sedimentary bodies. The observed sedimentary architecture is best explained by a net transgression, likely caused by lake level rise through time. This behaviour is not recorded within the best-studied and largest Eberswalde deposit likely due to subsequent burial by progradational lobes. In addition, planform evolution of sinuous channels within the largest Eberswalde deposit is investigated, and mapped chute cutoffs are suggested as implying that overbank flooding occurred.Open Acces

Automation bias and prescribing decision support – rates, mediators and mitigators

Purpose: Computerised clinical decision support systems (CDSS) are implemented within healthcare settings as a method to improve clinical decision quality, safety and effectiveness, and ultimately patient outcomes. Though CDSSs tend to improve practitioner performance and clinical outcomes, relatively little is known about specific impact of inaccurate CDSS output on clinicians. Although there is high heterogeneity between CDSS types and studies, reviews of the ability of CDSS to prevent medication errors through incorrect decisions have generally been consistently positive, working by improving clinical judgement and decision making. However, it is known that the occasional incorrect advice given may tempt users to reverse a correct decision, and thus introduce new errors. These systematic errors can stem from Automation Bias (AB), an effect which has had little investigation within the healthcare field, where users have a tendency to use automated advice heuristically. Research is required to assess the rate of AB, identify factors and situations involved in overreliance and propose says to mitigate risk and refine the appropriate usage of CDSS; this can provide information to promote awareness of the effect, and ensure the maximisation of the impact of benefits gained from the implementation of CDSS. Background: A broader literature review was carried out coupled with a systematic review of studies investigating the impact of automated decision support on user decisions over various clinical and non-clinical domains. This aimed to identify gaps in the literature and build an evidence-based model of reliance on Decision Support Systems (DSS), particularly a bias towards over-using automation. The literature review and systematic review revealed a number of postulates - that CDSS are socio-technical systems, and that factors involved in CDSS misuse can vary from overarching social or cultural factors, individual cognitive variables to more specific technology design issues. However, the systematic review revealed there is a paucity of deliberate empirical evidence for this effect. The reviews identified the variables involved in automation bias to develop a conceptual model of overreliance, the initial development of an ontology for AB, and ultimately inform an empirical study to investigate persuasive potential factors involved: task difficulty, time pressure, CDSS trust, decision confidence, CDSS experience and clinical experience. The domain of primary care prescribing was chosen within which to carry out an empirical study, due to the evidence supporting CDSS usefulness in prescribing, and the high rate of prescribing error. Empirical Study Methodology: Twenty simulated prescribing scenarios with associated correct and incorrect answers were developed and validated by prescribing experts. An online Clinical Decision Support Simulator was used to display scenarios to users. NHS General Practitioners (GPs) were contacted via emails through associates of the Centre for Health Informatics, and through a healthcare mailing list company. Twenty-six GPs participated in the empirical study. The study was designed so each participant viewed and gave prescriptions for 20 prescribing scenarios, 10 coded as “hard” and 10 coded as “medium” prescribing scenarios (N = 520 prescribing cases were answered overall). Scenarios were accompanied by correct advice 70% of the time, and incorrect advice 30% of the time (in equal proportions in either task difficulty condition). Both the order of scenario presentation and the correct/incorrect nature of advice were randomised to prevent order effects. The planned time pressure condition was dropped due to low response rate. Results: To compare with previous literature which took overall decisions into account, taking individual cases into account (N=520), the pre advice accuracy rate of the clinicians was 50.4%, which improved to 58.3% post advice. The CDSS improved the decision accuracy in 13.1% of prescribing cases. The rate of AB, as measured by decision switches from correct pre advice, to incorrect post advice was 5.2% of all cases at a CDSS accuracy rate of 70% - leading to a net improvement of 8%. However, the above by-case type of analysis may not enable generalisation of results (but illustrates rates in this specific situation); individual participant differences must be taken into account. By participant (N = 26) when advice was correct, decisions were more likely to be switched to a correct prescription, when advice was incorrect decisions were more likely to be switched to an incorrect prescription. There was a significant correlation between decision switching and AB error. By participant, more immediate factors such as trust in the specific CDSS, decision confidence, and task difficulty influenced rate of decision switching. Lower clinical experience was associated with more decision switching (but not higher AB rate). The rate of AB was somewhat problematic to analyse due to low number of instances – the effect could potentially have been greater. The between subjects effect of time pressure could not be investigated due to low response rate. Age, DSS experience and trust in CDSS generally were not significantly associated with decision switching. Conclusion: There is a gap in the current literature investigating inappropriate CDSS use, but the general literature supports an interactive multi-factorial aetiology for automation misuse. Automation bias is a consistent effect with various potential direct and indirect causal factors. It may be mitigated by altering advice characteristics to aid clinicians’ awareness of advice correctness and support their own informed judgement – this needs further empirical investigation. Users’ own clinical judgement must always be maintained, and systems should not be followed unquestioningly

Fast and frugal framing effects?

Three experiments examine whether simple pair-wise comparison judgments, involving the “recognition heuristic” (Goldstein & Gigerenzer, 2002), are sensitive to implicit cues to the nature of the comparison required. Experiments 1 & 2 show that participants frequently choose the recognized option of a pair if asked to make “larger” judgments but are significantly less likely to choose the unrecognized option when asked to make “smaller” judgments. Experiment 3 demonstrates that, overall, participants consider recognition to be a more reliable guide to judgments of a magnitude criterion than lack of recognition and that this intuition drives the framing effect. These results support the idea that, when making pair-wise comparison judgments, inferring that the recognized item is large is simpler than inferring that the unrecognized item is small

Time to decide? Simplicity and congruity in comparative judgment

What is the relationship between magnitude judgments relying on directly available characteristics versus probabilistic cues? Question frame was manipulated in a comparative judgment task previously assumed to involve inference across a probabilistic mental model (e.g., “which city is largest” – the “larger” question – versus “which city is smallest” – the “smaller” question). Participants identified either the largest or smallest city (Experiments 1a, 2) or the richest or poorest person (Experiment 1b) in a three-alternative forced choice (3-AFC) task (Experiment 1) or 2-AFC task (Experiment 2). Response times revealed an interaction between question frame and the number of options recognized. When asked the smaller question, response times were shorter when none of the options were recognized. The opposite pattern was found when asked the larger question: response time was shorter when all options were recognized. These task-stimuli congruity results in judgment under uncertainty are consistent with, and predicted by, theories of magnitude comparison which make use of deductive inferences from declarative knowledge

EVALUATING EXTENSIVE SHEEP FARMING SYSTEMS

Data from each of 5 commercial, extensive sheep farms in Cumbria, UK were used as parameters in a linear program (LP) representing labour and grazing management in such farming systems. The LP maximised ewe enterprise gross margin subject to constraints dictated by the labour availability and land types on each farm. Under the assumptions used, labour availability and price restricted ewe numbers well below those observed in practice on 2 farms i.e. land resources were adequate for the farming system practiced. On two other farms stocking levels and hence returns were limited by the availability of forage and hence feed input prices relative to output. On one farm, greater grassland productivity was the key determinant of system performance. It was concluded that a holistic systems approach was needed to properly evaluate these farming systems in terms of their potential contribution to animal welfare, land use, profit and hence their sustainabilityLivestock Production/Industries, Extensive, Sheep, Economics, LP,

Impacts of labour on interactions between economics and animal welfare in extensive sheep farms

This study quantified interactions between animal welfare and farm profitability in British extensive sheep farming systems. Qualitative welfare assessment methodology was used to assess welfare from the animal's perspective in 20 commercial extensive sheep farms and to estimate labour demand for welfare, based on the assessed welfare scores using data collected from farm inventories. The estimated labour demand was then used as a coefficient in a linear program based model to establish the gross margin maximising farm management strategy for given farm situations, subject to constraints that reflected current resource limitations including labour supply. Regression analysis showed a significant relationship between the qualitative welfare assessment scores and labour supply on the inventoried farms but there was no significant relationship between current gross margin and assessed welfare scores. However, to meet the labour demand of the best welfare score, a reduction in flock size and in the average maximum farm gross margin was often required. These findings supported the hypothesis that trade-offs between animal welfare and farm profitability are necessary in providing maximum animal welfare via on-farm labour and sustainable British extensive sheep farming systems.Sheep, Labour, Animal Welfare, Linear Programme, Livestock Production/Industries, C6, Q10, Q19, Q57,

Sexualisation, or the queer feminist provocations of Miley Cyrus

Miley Cyrus has increasingly occupied debates at the centre of feminist engagements with popular culture. Evoking concerns around young women and ‘sexualisation’, Cyrus emerges as a convergent signifier of sexualised media content and the girl-at-risk. As Cyrus is repeatedly invoked in these debates, she comes to function as the bad object of young femininity. Arguing, however, that Cyrus troubles the sexualisation thesis in the provocations of her creative practice, I suggest that this contested media figure exceeds the frames through which she is read. Thus, I ask: what kinds of insights might be possible if we were to transform the terms on which we approach this figure? Considering a selection of the images and performances that constitute the Cyrus archive, this article proposes a reading of Cyrus as performative provocation. Mobilising an existing sensibility of queer feminist struggle, Cyrus emerges as a disruptive, albeit contradictory, figure. Questions of privilege, limit and possibility emerge in this discussion, as well as what constitutes feminist struggle

The Grizzly, April 25, 2002

Pesta Appeals College\u27s Action • O\u27Flaherty Speaks to Ursinus about Human Rights • Diverse and Abundant Research Continues • Sex for Sale: What Drives the Porn Industry? • Final Exam Schedule • Jon Volkmer Named Montgomery County Poet Laureate • Greek Week Change Bad: An Opinion • Commencement and Baccalaureate Speakers Announced • Hockey Intramurals • Family or no Family: That is the Question for Many Career Womenhttps://digitalcommons.ursinus.edu/grizzlynews/1515/thumbnail.jp