Safety and efficacy of benzoic acid for pigs and poultry

The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked by the European Commission to deliver a scientific opinion on the safety and efficacy of benzoic acid as feed flavouring for piglets (suckling, weaned), pigs for fattening, sows (for reproduction, in order to have benefit in piglets), minor porcine species, chickens (for fattening, reared for laying), hens (laying, breeding), turkeys (for fattening, for breeding purposes, reared for breeding) and minor poultry species. Benzoic acid is safe for weaned piglets at 2,500 mg/kg feed, and for laying hens, turkeys and chickens for fattening at 500 mg/kg feed; no conclusions could be drawn for suckling piglets and sows. The conclusions on weaned piglets can be extended to pigs for fattening and extrapolated to growing minor porcine species. The conclusions on chickens/turkeys for fattening can be extended to chickens reared for laying and turkeys reared for breeding and extrapolated to minor poultry species up to the point of lay. In the absence of safety margin in laying hens, no conclusions can be reached for minor poultry species for laying/breeding. The use of the additive is not expected to pose a risk to consumer, considering that the additive is rapidly metabolised with very low deposition, if any, in edible tissues of pigs and poultry and that foods of animal origin provide a very minor contribution, if any, to the overall dietary intake of benzoic acid. Owing to the unlikelihood of exposure, no risk to users upon inhalation of the additive is expected; the additive is not a skin sensitiser, but is a skin/ eye irritant. The proposed use of the additive does not pose environmental risks. Benzoic acid is authorised as food flavouring and its function in feed is essentially the same; no further demonstration of efficacy is necessary

Key Competences in Europe: Opening Doors for Lifelong Learners Across the School Curriculum and Teacher Education

[...] The aim of the study is to provide a comparative overview of policy and practice concerning the development and implementation of key competences in the education systems of the 27 Member States of the European Union. In particular, the study assesses the implementation of the 8 key competences contained in the European Reference Framework of Key Competences in primary and secondary schools across the EU as well as the extent to which initial and in-service education and training of teachers equips them with the skills and competences necessary to deliver key competences effectively. [...

Critical thinking for 21st-century education: A cyber-tooth curriculum?

It is often assumed that the advent of digital technologies requires fundamental change to the curriculum and to the teaching and learning approaches used in schools around the world to educate this generation of “digital natives” or the “net generation”. This article analyses the concepts of 21st-century skills and critical thinking, to understand how these aspects of learning might contribute to a 21st-century education. The author argues that, although both critical thinking and 21st-century skills are indeed necessary in a curriculum for a 21st-century education, they are not sufficient, even in combination. The role of knowledge and an understanding of differing cultural perspectives and values indicate that education should also fit local contexts in a global world and meet the specific needs of students in diverse cultures. It should also fit the particular technical and historical demands of the 21st century in relation to digital skills

Advances in atomic force microscopy

This article reviews the progress of atomic force microscopy (AFM) in ultra-high vacuum, starting with its invention and covering most of the recent developments. Today, dynamic force microscopy allows to image surfaces of conductors \emph{and} insulators in vacuum with atomic resolution. The mostly used technique for atomic resolution AFM in vacuum is frequency modulation AFM (FM-AFM). This technique, as well as other dynamic AFM methods, are explained in detail in this article. In the last few years many groups have expanded the empirical knowledge and deepened the theoretical understanding of FM-AFM. Consequently, the spatial resolution and ease of use have been increased dramatically. Vacuum AFM opens up new classes of experiments, ranging from imaging of insulators with true atomic resolution to the measurement of forces between individual atoms.Comment: In press (Reviews of Modern Physics, scheduled for July 2003), 86 pages, 44 figure

Amendment of soil by biochars and activated carbons to reduce chlordecone bioavailability in piglets

International audienceChlordecone (Kepone or CLD) is a highly persistent pesticide formerly used in French West Indies. Nowadays high levels of this pesticide are still found in soils which represent a subsequent source of contamination for outdoor-reared animals. In that context, sequestering matrices like biochars or activated carbons (ACs) are believed to efficiently decrease the bioavailability of such compounds when added to contaminated soils. The present study intends to test the respective efficiency of soil amendment strategies using commercial ACs or biochars (obtained by a 500°C or 700°C pyrolysis of 4 distinct type of wood). This study involved three experimental steps. The first one characterized specific surface areas of biochars and ACs. The second one assessed CLD-availability of contaminated artificial soils (50 µg.g-1 of Dry Matter) amended with 5% of biochar or AC (mass basis). The third one assessed CLD bioavailability of those artificial soils through an in vivo assay. To limit ethically the number of animals, selections of the most promising media were performed between each experimental steps. Forty four castrated male 40-day-old piglets were exposed during 10 day to amended artificial soils according their group (n=4). Only treatment groups exposed through amended soil with AC presented a significant decrease of concentrations of CLD in liver and adipose tissue in comparison with the control group (p<0.001). A non-significant decrease was obtained by amending artificial soil with biochars. This decrease was particularly high for a coconut shell activated carbon were relative bioavailability was found lower than 3.2% for both tissues. This study leads to conclude that AC introduced in CLD contaminated soil should strongly reduce CLD bioavailability