Statistical assumptionStatistics, like all mathematical disciplines, does not infer valid conclusions from nothing. Inferring interesting conclusions about real statistical populations almost always requires some background assumptions. Those assumptions must be made carefully, because incorrect assumptions can generate wildly inaccurate conclusions. Here are some examples of statistical assumptions: Independence of observations from each other (this assumption is an especially common error). Independence of observational error from potential confounding effects.
Protéine membranaireLes protéines membranaires constituent l'une des trois principales classes de protéines à côté des protéines fibreuses et des protéines globulaires. Suivant le type de cellule et d'organite cellulaire, une membrane peut contenir des centaines de protéines différentes. Chaque protéine membranaire possède une orientation définie par rapport au cytoplasme : c'est pourquoi les propriétés des faces de la membrane sont très différentes. On parle de l’asymétrie de la membrane.
Coil–globule transitionIn polymer physics, the coil–globule transition is the collapse of a macromolecule from an expanded coil state through an ideal coil state to a collapsed globule state, or vice versa. The coil–globule transition is of importance in biology due to the presence of coil-globule transitions in biological macromolecules such as proteins and DNA. It is also analogous with the swelling behavior of a crosslinked polymer gel and is thus of interest in biomedical engineering for controlled drug delivery.
International relations theoryInternational relations theory is the study of international relations (IR) from a theoretical perspective. It seeks to explain behaviors and outcomes in international politics. The four most prominent schools of thought are realism, liberalism, constructivism, and rational choice. Whereas realism and liberalism make broad and specific predictions about international relations, constructivism and rational choice are methodological approaches that focus on certain types of social explanation for phenomena.
Néoréalisme (relations internationales)Le néoréalisme (aussi appelé réalisme structurel) est un courant théorique dans la discipline des relations internationales. Il a été fondé par Kenneth Waltz dans son ouvrage Theory of International Politics (1979). Des auteurs comme Robert Gilpin, Joseph Grieco, Robert Jervis, John Mearsheimer, Jack Snyder, Stephen Walt peuvent également être classés dans ce courant. Le néoréalisme s'est développé principalement dans la science politique américaine.
Constructive neutral evolutionConstructive neutral evolution (CNE) is a theory that seeks to explain how complex systems can evolve through neutral transitions and spread through a population by chance fixation (genetic drift). Constructive neutral evolution is a competitor for both adaptationist explanations for the emergence of complex traits and hypotheses positing that a complex trait emerged as a response to a deleterious development in an organism.