The purpose of the test is to measure the capacity of a chemical to activate or inhibit the transcription of a genetic construct (THb/ZIP-GFP X. laevis eleutheroembryos) either by binding to the thyroid hormone receptor or by modifying the amount of thyroid hormone available for transcription....

The bacterial reverse mutation test uses amino-acid requiring at least five strains of Salmonella typhimurium and Escherichia coli to detect point mutations by base substitutions or frameshifts. The principle of this bacterial reverse mutation test is that it detects mutations which revert...

Dominant lethal (DL) effects cause embryonic or foetal death. Induction of a dominant lethal event after exposure to a test substance (liquid, solid, vapour or gas, …) indicates that the substance has affected germinal tissue of the test species. Dominant lethals are generally accepted to be...

Fewer 15-year-olds in East Asian countries reported that they use memorisation than did 15‑year‑olds in some of the English-speaking countries to whom they are often compared. In no PISA-participating education system did boys report more intensive use of memorisation than girls when...

Some 65% of socio-economically advantaged students reported that they know well or have often heard of the concept of quadratic function, on average across OECD countries; but only 43% of disadvantaged students so reported. On average across OECD countries, the 20% of students who are most...

Diversity in the classroom includes differences in the way students’ brains learn, or neurodiversity. Neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit hyperactive disorder (ADHD) affect increasingly large numbers of students. Education systems must work...

This Public Procurement Brief presents two new EU public procurement Directives (2014/24/EU and 2014/25/EU) on procurement by public and utilities sectors. The Directives are part of a recently adopted EU legislative package reforming the EU public procurement rules. The Brief provides an...

The public procurement Directives only apply if a body is a contracting authority (contracting entity in the Utilities sector) within the definition of the Directives. SIGMA Brief 3 gives guidance on the notion of a contracting authority/entity under the directives (especially the concept of...