A 61-year-old woman presented with the primary complaints of chest heaviness and dysphagia over the past 10 years. Extensive work-up included a computerized tomographic angiography that revealed a right aortic arch with an aberrant left subclavian artery with a vascular ring completed by the fibrotic ligamentum arteriosum connecting the proximal aberrant left subclavian artery to the left pulmo...

Let K be a noncommutative division ring with center Z and multiplicative group K*. Hua [2; 3] proved that (i) K*/Z* is a group without center, and (ii) K* is not solvable. A generalization (Theorem 1) will be given here which contains as a special case (Theorem 2) the fact that K*/Z* has no Abelian normal subgroups. This latter theorem obviously contains both (i) and (ii). As a further corollar...

Proper placement of the cell division site in some rod-shaped bacteria requires two different negative regulatory systems, nucleoid occlusion and the Min proteins. Caulobacter crescentus lacks these systems, but recent work has uncovered a novel regulator that achieves the same goals.

FtsZ, a tubulin homologue and the major constituent of the bacterial Z ring, has been shown to assemble into curved filament bundles, which exhibit GTP-hydrolysis-dependent turnover. Surprisingly, the presence of its membrane adaptor FtsA renders this turnover directional, inducing treadmilling and collective circular motion of filaments in vitro.

In this paper, we present an isomorphism between the ring of general polynomials over a division algebra D with center F and the group ring of the free monoid with [D : F ] variables over D. Using this isomorphism, we define the characteristic polynomial of any matrix over any division algebra, i.e., a general polynomial with one variable over the algebra whose roots are precisely the left eige...

A polynomial f(t) in an Ore extension K[t;S,D] over a division ring K is a Wedderburn polynomial if f(t) is monic and is the minimal polynomial of an algebraic subset of K. These polynomials have been studied in [LL5]. In this paper, we continue this study and give some applications to triangulation, diagonalization and eigenvalues of matrices over a division ring in the general setting of (S,D...

Chloroplast division is driven by the simultaneous constriction of the inner FtsZ ring (Z ring) and the outer DRP5B ring. The assembly and constriction of these rings in Arabidopsis (Arabidopsis thaliana) are coordinated partly through the inner envelope membrane protein ACCUMULATION AND REPLICATION OF CHLOROPLASTS6 (ARC6). Previously, we showed that PARC6 (PARALOG OF ARC6), also in the inner e...

If [Formula: see text] is a directed graph and field, the Leavitt path algebra of over naturally graded by group integers We formulate properties which are equivalent with being crossed product, skew ring, or ring respect to this natural grading. state main result so that also characterized in terms pre-ordered Grothendieck text]-group text]. has finitely many vertices, we characterize when str...

1. Introduction. We shall say that an integral domain1 R satisfies condition (M) if any two nonzero elements of R have a nonzero common right multiple. In this note it is proved that if 5 is an extension of a ring R such that S is, roughly speaking, a noncommutative polynomial ring in one variable with R as a coefficient ring, and if R has the property (M), then 5 has property (M). In case R is...

Despite a century of research into the nature of animal cell division, a molecular explanation for the positioning of the actomyosin contractile ring has remained elusive. The discovery of a novel interaction between regulators of Rho family small GTPases has revealed a link between the mitotic microtubules and the contractile ring during the later stages of mitosis. The properties of the inter...