Polyhydroxybutyrate accumulation by a Serratia sp

A strain of Serratia sp. showed intracellular electron-transparent inclusion bodies when incubated in the presence of citrate and glycerol 2-phosphate without nitrogen source following pregrowth under carbon-limitation in continuous culture. About 1.3 mmol citrate were consumed per 450 mg\ud biomass, giving a calculated yield of maximally 55% of stored material per g of biomass dry wt. The inclusion bodies were stained with Sudan Black and Nile Red (NR), suggesting a lipid material, which was confirmed as polyhydroxybutyrate (PHB) by analysis of molecular fragments by GC and by FTIR spectroscopy of isolated bio-PHB in comparison with reference material. Multi-parameter flow cytometry in conjunction with NR fluorescence, and electron microscopy, showed that not all cells contained heavy PHB bodies, suggesting the potential for increasing\ud the overall yield. The economic attractiveness is\ud enhanced by the co-production of nanoscale hydroxyapatite\ud (HA), a possible high-value precursor for bone replacement materials

A large-scale examination of the effectiveness of anonymous marking in reducing group performance differences in higher education assessment

The present research aims to more fully explore the issues of performance differences in higher education assessment, particularly in the context of a common measure taken to address them. The rationale for the study is that, while performance differences in written examinations are relatively well researched, few studies have examined the efficacy of anonymous marking in reducing these performance differences, particularly in modern student populations. By examining a large archive (N = 30674) of assessment data spanning a twelve-year period, the relationship between assessment marks and factors such as ethnic group, gender and socio-environmental background was investigated. In particular, analysis focused on the impact that the implementation of anonymous marking for assessment of written examinations and coursework has had on the magnitude of mean score differences between demographic groups of students. While group differences were found to be pervasive in higher education assessment, these differences were observed to be relatively small in practical terms. Further, it appears that the introduction of anonymous marking has had a negligible effect in reducing them. The implications of these results are discussed, focusing on two issues, firstly a defence of examinations as a fair and legitimate form of assessment in Higher Education, and, secondly, a call for the re-examination of the efficacy of anonymous marking in reducing group performance differences

Safety of Levetiracetam in paediatrics: a systematic review

Objective To identify adverse events (AEs) associated with Levetiracetam (LEV) in children. Methods Databases EMBASE (1974-February 2015) and Medline (1946-February 2015) were searched for articles in which paediatric patients (≤18 years) received LEV treatment for epilepsy. All studies with reports on safety were included. Studies involving adults, mixed age population (i.e. children and adults) in which the paediatric subpopulation was not sufficiently described, were excluded. A meta-analysis of the RCTs was carried out and association between the commonly reported AEs or treatment discontinuation and the type of regimen (polytherapy or monotherapy) was determined using Chi2 analysis. Results Sixty seven articles involving 3,174 paediatric patients were identified. A total of 1,913 AEs were reported across studies. The most common AEs were behavioural problems and somnolence, which accounted for 10.9% and 8.4% of all AEs in prospective studies. 21 prospective studies involving 1120 children stated the number of children experiencing AEs. 47% of these children experienced AEs. Significantly more children experienced AEs with polytherapy (64%) than monotherapy (22%) (p<0.001). Levetiracetam was discontinued in 4.5% of all children on polytherapy and 0.9% on monotherapy (p<0.001), the majority were due to behavioural problems. Conclusion Behavioural problems and somnolence were the most prevalent adverse events to LEV and the most common causes of treatment discontinuation. Children on polytherapy have a greater risk of adverse events than those receiving monotherapy

Mediation, moderation, and interaction: Definitions, discrimination and (some) means of testing

In 1986 Baron and Kenny set out to clarify the terms “Mediation” and “Moderation” as used in the social sciences (with the origins of each described by Roe, 2012). Twenty six years later, the seminal paper that this collaboration resulted in (Baron &amp; Kenny, 1986) has been cited over 35,000 times (35,672 via Google Scholar as of 09/01/2013). However, despite this extensive record of citation, uncertainty continues to surround the use of these terms in social science research and they have received relatively little attention in specifically educational research (cf. Kraemer, Stice, Kazdin, Offord, &amp; Kupfer, 2001)

The drivers of academic success for ‘bright’ but disadvantaged students: A longitudinal study of AS and A-level outcomes in England

The study identified a sub-group of high attaining (bright) disadvantaged students at the end primary schooling at age 11 and followed their progress across secondary education with a particular focus on their success in advanced level (AS and A-levels) public examinations in England. Based on an sample of approximately 3000 children tracked from age 3 to age 18 multilevel logistic regression identified factors (child, family, home learning and educational) that predicted being high achieving for disadvantaged students at age 11 and also what predicted later success at age 18. Findings point to the continued effects of pre-school experiences, the early years home learning environment and out of school learning. Attending a a higher quality secondary school also improved outcomes. Policy implications for the development and evaluation of interventions intended to reduce the equity gap in achievement are discussed

Methodological and scientific properties of School Effectiveness Research: exploring the underpinnings, evolution and future directions of the field

This chapter examines the origins, methodological properties, and evolution of school effectiveness research (SER), and the broader and more recent focus of educational effectiveness research (EER), over the last half century. It provides a brief overview of the main disciplinary roots and examines the essential features that underpin the two fields. It also seeks to identify some of the key features of more recent work, conducted in the twenty-first century, showing how the field has evolved since the publication of the first international handbook in 2000 (Teddlie and Reynolds, 2000)

Background to success: differences in A-Level entries by ethnicity, neighbourhood and gender

This report investigates patterns of academic attainment for different subgroups of a longitudinal sample of more than 3,000 students whose educational outcomes were studied across different phases of school and pre-school from age three to age 18. The report is the second in a series produced using the EPPSE dataset for the Sutton Trust studying AS and A-level outcomes for students and the drivers of academic success in advanced level studies. In this report by Pam Sammons, Katalin Toth, and Kathy Sylva, we study equity differences in outcomes for different groups of students. We also illustrate the powerful role of background factors such as gender, ethnicity and disadvantage in shaping educational outcomes, success and educational futures

Background to success: differences in A-Level entries by ethnicity, neighbourhood and gender

This report investigates patterns of academic attainment for different subgroups of a longitudinal sample of more than 3,000 students whose educational outcomes were studied across different phases of school and pre-school from age three to age 18. The report is the second in a series produced using the EPPSE dataset for the Sutton Trust studying AS and A-level outcomes for students and the drivers of academic success in advanced level studies. In this report by Pam Sammons, Katalin Toth, and Kathy Sylva, we study equity differences in outcomes for different groups of students. We also illustrate the powerful role of background factors such as gender, ethnicity and disadvantage in shaping educational outcomes, success and educational futures

Subject to Background: What promotes better achievement by bright but disadvantaged students?

Written by Pam Sammons, Katalin Toth, and Kathy Sylva, this report looks at children’s education careers by drawing on data from a sample of more than 3,000 young people who have been tracked through school since the age of three. In particular, this research identified a group of disadvantaged children, establishing what predicted their academic success at the age of 11 and following them up to age 18. The findings reveal that bright but disadvantaged children are considerably less likely to take the subjects most likely to get them into good universities than their more advantaged counterparts