Miedo, inseguridad, repulsión, nerviosismo, peligro, ansiedad… son algunas de las sensaciones y sentimientos que la mayoría de la gente siente al encontrarse con pandillas juveniles en las calles de la ciudad; sin embargo, ...

The solvability of the word problem for Yamamura’s HNN-extensions [S; A1, A2; ϕ] has been proved in some particular cases. However, we show that, contrary to the group case, the word problem for [S; A1A2; ϕ] is undecidable ...

An understanding of the adaptations made by plants in their nitrogen (N) uptake systems in response to reduced N supply is important to the development of cereals with enhanced N uptake efficiency (NUpE). Twenty seven ...