In a widely held view of vertebrate CNS development, neurons, astrocytes, and oligodendrocytes arise from a common tripotent progenitor cell. However, tripotent progenitors have never been detected in developing embryos. In this issue of Neuron, Gabay et al. show that tripotent progenitors can be created in vitro by deregulation of normal dorsoventral positional cues.

This paper deals with the Hermitian H(A) and skew-Hermitian part S(A) of a complex matrix A. We characterize all complex matrices A such that H(A), respectively S(A), is a potent matrix. Two approaches are used: characterizations of idempotent and tripotent Hermitian matrices of the form [ X Y ∗ Y 0 ] , and a singular value decomposition of A. In addition, a relation between the potency of H(A)...

This paper deals with the Hermitian H(A) and skew-Hermitian part S(A) of a complex matrix A. We characterize all complex matrices A such that H(A), respectively S(A), is a potent matrix. Two approaches are used: characterizations of idempotent and tripotent Hermitian matrices of the form [ X Y ∗ Y 0 ] , and a singular value decomposition of A. In addition, a relation between the potency of H(A)...

in this article, we characterize the involutiveness of the linear combination of the forma1a1 +a2a2 when a1, a2 are nonzero complex numbers, a1 is a quadratic or tripotent matrix,and a2 is arbitrary, under certain properties imposed on a1 and a2.

‎A rank equality is established for the sum of finitely many tripotent matrices via elementary block matrix operations‎. ‎Moreover‎, ‎by using this equality and Theorems 8 and 10 in [Chen M‎. ‎and et al‎. ‎On the open problem related to rank equalities for the sum of finitely many idempotent matrices and its applications‎, ‎The Scientific World Journal 2014 (2014)‎, ‎Article ID 702413‎, ‎7 page...

Let T1 and T2 be two commuting n × n tripotent matrices and c1, c2 two nonzero complex numbers. The problem of when a linear combination of the form T = c1T1 + c2T2 is nonsingular is considered. Some other nonsingularitytype relationships for tripotent matrices are also established. Moreover, a statistical interpretation of the results is pointed out.

In this article, we characterize the involutiveness of the linear combination of the forma1A1 +a2A2 when a1, a2 are nonzero complex numbers, A1 is a quadratic or tripotent matrix,and A2 is arbitrary, under certain properties imposed on A1 and A2.

Overexpression of transcription factors has been used to directly reprogram somatic cells into a range of other differentiated cell types, including multipotent neural stem cells (NSCs), that can be used to generate neurons and glia. However, the ability to maintain the NSC state independent of the inducing factors and the identity of the somatic donor cells remain two important unresolved issu...