104 research outputs found

    Generalized Structural Description of Calcium–Sodium Aluminosilicate Hydrate Gels: The Cross-Linked Substituted Tobermorite Model

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    Structural models for the primary strength and durability-giving reaction product in modern cements, a calcium (alumino)silicate hydrate gel, have previously been based solely on non-cross-linked tobermorite structures. However, recent experimental studies of laboratory-synthesized and alkali-activated slag (AAS) binders have indicated that the calcium–sodium aluminosilicate hydrate [C-(N)-A-S-H] gel formed in these systems can be significantly cross-linked. Here, we propose a model that describes the C-(N)-A-S-H gel as a mixture of cross-linked and non-cross-linked tobermorite-based structures (the cross-linked substituted tobermorite model, CSTM), which can more appropriately describe the spectroscopic and density information available for this material. Analysis of the phase assemblage and Al coordination environments of AAS binders shows that it is not possible to fully account for the chemistry of AAS by use of the assumption that all of the tetrahedral Al is present in a tobermorite-type C-(N)-A-S-H gel, due to the structural constraints of the gel. Application of the CSTM can for the first time reconcile this information, indicating the presence of an additional activation product that contains highly connected four-coordinated silicate and aluminate species. The CSTM therefore provides a more advanced description of the chemistry and structure of calcium–sodium aluminosilicate gel structures than that previously established in the literature

    Translating upwards: linking the neural and social sciences via neuroeconomics

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    The social and neural sciences share a common interest in understanding the mechanisms that underlie human behaviour. However, interactions between neuroscience and social science disciplines remain strikingly narrow and tenuous. We illustrate the scope and challenges for such interactions using the paradigmatic example of neuroeconomics. Using quantitative analyses of both its scientific literature and the social networks in its intellectual community, we show that neuroeconomics now reflects a true disciplinary integration, such that research topics and scientific communities with interdisciplinary span exert greater influence on the field. However, our analyses also reveal key structural and intellectual challenges in balancing the goals of neuroscience with those of the social sciences. To address these challenges, we offer a set of prescriptive recommendations for directing future research in neuroeconomics

    The influence of journal submission guidelines on authors' reporting of statistics and use of open research practices.

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    From January 2014, Psychological Science introduced new submission guidelines that encouraged the use of effect sizes, estimation, and meta-analysis (the "new statistics"), required extra detail of methods, and offered badges for use of open science practices. We investigated the use of these practices in empirical articles published by Psychological Science and, for comparison, by the Journal of Experimental Psychology: General, during the period of January 2013 to December 2015. The use of null hypothesis significance testing (NHST) was extremely high at all times and in both journals. In Psychological Science, the use of confidence intervals increased markedly overall, from 28% of articles in 2013 to 70% in 2015, as did the availability of open data (3 to 39%) and open materials (7 to 31%). The other journal showed smaller or much smaller changes. Our findings suggest that journal-specific submission guidelines may encourage desirable changes in authors' practices

    Awareness, concern and willingness to adopt biosecure behaviours: public perceptions of invasive tree pests and pathogens in the UK

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    The growing incidence of invasive tree pest and disease outbreaks is recognised as an increasing threat to ecosystem services and human wellbeing. Linked to global trade, human movement and climate change, a number of outbreaks have attracted high public and media attention. However, there is surprisingly little evidence characterising the nature of public attentiveness to these events, nor how publics might respond to evolving outbreaks and the management actions taken. This paper presents findings from an online questionnaire involving 1334 respondents nationally-representative of the British public to assess awareness, concern and willingness to adopt biosecure behaviours. Despite revealing low levels of awareness and knowledge, the results indicate that the British public is concerned about the health of trees, forests and woodlands and is moderately willing to adopt biosecure behaviours. A key finding is that membership of environmental organisations and strong place identity are likely to engender higher awareness and levels of concern about tree pests and diseases. Further, those who visit woodlands regularly are likely to be more aware than non-visitors, and gardeners are more likely to be concerned than non-gardeners. Women, older respondents, those with strong place identity and dependence, members of environmental organisations, woodland visitors and gardeners were most likely to express a willingness to adopt biosecure behaviours. A comparison with findings from a survey conducted by the authors 3 years previously shows a decline over time in awareness, concern and willingness

    A Triple Test for Behavioral Economics Models and Public Health Policy

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    We propose a triple test to evaluate the usefulness of behavioral economics models for public health policy. Test 1 is whether the model provides reasonably new insights. Test 2 is on whether these have been properly applied to policy settings. Test 3 is whether they are corroborated by evidence. Where a test is not passed, this may point to directions for needed further research. We exemplify by considering the cases of social interactions models, self-control models and, in relation to health message framing, prospect theory; out of these, only a correctly applied prospect theory fully passes the tests at present

    Combining the contributions of behavioral economics and other social sciences in understanding taxation and tax reform

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    This paper extends previous work presented at the SABE/IAREP conference at St Mary’s University, Halifax (James, 2009). In the earlier paper it was shown that conventional economic theory is used to make the case for tax reform but does not always adequately incorporate all the relevant factors. However, an approach based on behavioral economics can make the difference between success and failure. In this paper the contributions of other social sciences are also included. Taxation is a particularly appropriate subject to explore the integration of the social sciences since they have all devoted considerable attention to it. It can be seen that different social sciences suggest a range of variables that might be taken into account in addition to those included in mainstream economics. Other social sciences also offer different methodological approaches and consider the possibility of different outcomes of the fiscal process. The paper concludes that it is not easy to integrate the social sciences in a single approach to the study of tax and tax policy. There may also be the risk of encouraging inappropriate integration - researchers operating outside their expertise can produce results that are not helpful. However, comparing the contribution of behavioral economics with those of the social sciences more generally, it can be seen that behavioral economics can offer a framework within which these areas can be examined. Indeed, it may be a useful channel to add the contributions of other social sciences to mainstream economic research

    Mood and the Market: Can Press Reports of Investors’ Mood Predict Stock Prices?

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    We examined whether press reports on the collective mood of investors can predict changes in stock prices. We collected data on the use of emotion words in newspaper reports on traders’ affect, coded these emotion words according to their location on an affective circumplex in terms of pleasantness and activation level, and created indices of collective mood for each trading day. Then, by using time series analyses, we examined whether these mood indices, depicting investors’ emotion on a given trading day, could predict the next day’s opening price of the stock market. The strongest findings showed that activated pleasant mood predicted increases in NASDAQ prices, while activated unpleasant mood predicted decreases in NASDAQ prices. We conclude that both valence and activation levels of collective mood are important in predicting trend continuation in stock prices
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