Above a swamp: A theory of high-quality scientific production

We elaborate a model of the incentives of scientists to perform activities of control and criticism when these activities, just like the production of novel findings, are costly, and we study the strategic interaction between these incentives. We then use the model to assess policies meant to enhance the reliability of scientific knowledge. We show that a certain fraction of low-quality science characterizes all the equilibria in the basic model. In fact, the absence of detected low-quality research can be interpreted as the lack of verification activities and thus as a potential limitation to the reliability of a field. Incentivizing incremental research and verification activities improves the expected quality of research; this effect, however, is contrasted by the incentives to free ride on performing verification if many scientists are involved, and may discourage scientists to undertake new research in the first place. Finally, softening incentives to publish does not enhance quality, although it increases the fraction of detected low-quality papers. We also advance empirical predictions and discuss the insights for firms and investors as they “scout” the scientific landscape.     

Seasonal changes in physical activity during school recess and lunchtime among Australian children

This study examined how children’s physical activity levels during recess and lunchtime and the contribution of recess and lunchtime to daily physical activity differed across seasons. Three hundred and twenty-six children aged 8–11 years from Australia participated. Physical activity was measured every 15-seconds using hip-mounted ActiGraph accelerometers for 7 consecutive days during the winter (n = 246), spring (n = 211), summer (n = 161) and autumn terms (n = 139). Data were collected 2012–2013. Time spent in light- (LPA) moderate- (MPA), vigorous- (VPA), and moderate- to vigorous-intensity physical activity (MVPA) during recess and lunchtime were calculated. Longitudinal data were analysed using multilevel analyses and adjusted for potential confounders. The results showed that compared to winter, children engaged in significantly less MVPA and VPA in spring and summer during lunchtime (p < 0.05). No significant changes were observed during recess. The contribution of lunchtime to VPA and MVPA significantly decreased in spring and summer compared to winter (p < 0.05). Children’s lunchtime physical activity levels decreased between winter and spring and summer, with greater declines observed in VPA. Strategies to increase physical activity levels in every season are needed during lunchtime, with a greater emphasis on warmer months.     

Exploring criteria for successful query expansion in the genomic domain

Query Expansion is commonly used in Information Retrieval to overcome vocabulary mismatch issues, such as synonymy between the original query terms and a relevant document. In general, query expansion experiments exhibit mixed results. Overall TREC Genomics Track results are also mixed; however, results from the top performing systems provide strong evidence supporting the need for expansion. In this paper, we examine the conditions necessary for optimal query expansion performance with respect to two system design issues: IR framework and knowledge source used for expansion. We present a query expansion framework that improves Okapi baseline passage MAP performance by 185%. Using this framework, we compare and contrast the effectiveness of a variety of biomedical knowledge sources used by TREC 2006 Genomics Track participants for expansion. Based on the outcome of these experiments, we discuss the success factors required for effective query expansion with respect to various sources of term expansion, such as corpus-based cooccurrence statistics, pseudo-relevance feedback methods, and domain-specific and domain-independent ontologies and databases. Our results show that choice of document ranking algorithm is the most important factor affecting retrieval performance on this dataset. In addition, when an appropriate ranking algorithm is used, we find that query expansion with domain-specific knowledge sources provides an equally substantive gain in performance over a baseline system.

Heirs and Spares: Elite Fathers and Their Sons in the Literary Sources of Umayyad Iberia

ABSTRACT

In the medieval Islamic world, elite men were the benchmark of hegemonic masculinity and social power. A presumption of masculine authority within the household shaped the way early medieval rulers were described by chroniclers, and how medieval fathers related to their sons. The formal and informal ways in which they interacted with lower status men – whether their clients, their courtiers, or their sons – were hedged about with the symbolic language of gender. The article focuses on the ways in which certain Andalusī literary sources talk about relations of fathers and their sons with the ruling Umayyad family, to offer an additional dimension to our picture of how the dynasty conceptualised and legitimised its power.     

Effects of strength,explosive and plyometric training on energy cost of running in ultra-endurance athletes

The aim of the present study was to evaluate the effects of a 12-week home-based strength, explosive and plyometric (SEP) training on the cost of running (Cr) in well-trained ultra-marathoners and to assess the main mechanical parameters affecting changes in Cr. Twenty-five male runners (38.2?±?7.1 years; body mass index: 23.0?±?1.1?kg·m^?2; V˙O₂max: 55.4?±?4.0 mlO₂·kg^?1·min^?1) were divided into an exercise (EG?=?13) and control group (CG?=?12). Before and after a 12-week SEP training, Cr, spring-mass model parameters at four speeds (8, 10, 12, 14?km·h^?1) were calculated and maximal muscle power (MMP) of the lower limbs was measured. In EG, Cr decreased significantly (p?<?.05) at all tested running speeds (?6.4?±?6.5% at 8?km·h^?1; ?3.5?±?5.3% at 10?km·h^?1; ?4.0?±?5.5% at 12?km·h^?1; ?3.2?±?4.5% at 14?km·h^?1), contact time (t_c) increased at 8, 10 and 12?km·h^?1 by mean +4.4?±?0.1% and t_a decreased by ?25.6?±?0.1% at 8?km·h^?1 (p?<?.05). Further, inverse relationships between changes in Cr and MMP at 10 (p?=?.013; r?=??0.67) and 12?km·h^?1 (p?<?.001; r?=??0.86) were shown. Conversely, no differences were detected in the CG in any of the studied parameters. Thus, 12-week SEP training programme lower the Cr in well-trained ultra-marathoners at submaximal speeds. Increased t_c and an inverse relationship between changes in Cr and changes in MMP could be in part explain the decreased Cr. Thus, adding at least three sessions per week of SEP exercises in the normal endurance-training programme may decrease the Cr.     

Predictors of multiple injuries in individual distance runners: A retrospective study of 75,401 entrants in 4 annual races–SAFER XX

BackgroundThere are limited data on factors that predict an increased risk of multiple injuries among distance runners. The objective of this study was to determine risk factors that are predictive of individual runners with a high annual multiple injury risk (MIR).MethodsA retrospective, cross-sectional study at 4 annual (2012–2015) Two Oceans 21.1 km and 56.0 km races in South Africa with 75,401 consenting race entrants. Running-related injury data were collected retrospectively through an online pre-race medical screening questionnaire. The average number of injuries for each runner every year was calculated by taking a runner''s race entry history and injury history into account and categorizing entrants into 4 MIR categories (high, intermediate, low, and very low (reference)). Multiple logistic regression modeling (odds ratios) was used to determine whether the following factors were predictive of a high MIR (average > 1 injury/year): demographics, training and racing, chronic-disease history (composite chronic disease score (CCDS)), and history of allergies.ResultsOf all entrants, 9.2% reported at least 1 injury, and 0.4% of entrants were in the high MIR category; the incidence rate was 2.5 injuries per 10 runner-years (95% confidence interval (95%CI): 2.4–2.7). Significant factors predictive of runners in the high MIR category were: running for > 20 years: OR = 2.0 (95%CI: 1.3–3.1; p = 0.0010); a higher CCDS: OR = 2.2 (95%CI: 2.0–2.4; p < 0.0001); and a history of allergies: OR = 2.8 (95%CI: 2.0–3.8; p < 0.0001).ConclusionRunners who have been running recreationally for > 20 years and those with multiple chronic diseases or a history of allergies were at higher risk of multiple running-related injuries. This high-risk group can be targeted for further study and possible injury-prevention interventions.     

Reading and Writing: Digital Directions

The authors show that IT hardware and software are having an effect on literacy. As well as being aware of those changes, English teachers, they argue, should be exploiting IT for the development of those reading and writing skills necessary for the future. The article goes on to exemplify, through an exploration of how it came to be written, some of the processes and opportunities identified earlier.     

Making connections: a conference approach to developing transformative environmental and sustainability education within initial teacher education

Abstract

Children today face significant challenges in response to living in a globalised world and the predicted environmental threats to the planet. However, implementing environmental and sustainability education (ESE) within schools can be complex and is often ignored within initial teacher education (ITE). In response, this project aimed to evaluate pedagogies for developing transformative learning for ESE within the context of university-based ITE. We ran a conference for trainee teachers informed by critical, participatory and arts-based pedagogic approaches. Alongside this, we undertook an interpretive case study, collecting data through questionnaires, focus groups and in-conference spoken reflection. Findings suggest trainee teachers gained a more nuanced understanding of the value and nature of ESE, as well as more affective and informed engagement with it, across the conference. Implications for ESE within ITE focus around the potential of pedagogies which provide affective experiences, in particular participatory and arts-based pedagogical approaches, for inspiring and empowering trainee teachers to enter into schools and develop their own ESE practice as classroom teachers.