In this issue of the Journal, Ghosh et al. (1) describe the application of two visual assessments to predict breast cancer risk—lobular involution, a histological observation, and mammographic breast density (MBD), a radiological assessment. Previously, this group has demonstrated that more extensive lobular involution was inversely related to both MBD (2) and breast cancer risk (3) in a cohort...

Abstract Let $G$ be a finite permutation group of degree $n$ and let ${\rm ifix}(G)$ the involution fixity , which is maximum number fixed points an involution. In this paper, we study almost simple primitive groups whose socle $T$ alternating or sporadic group; our main result classifies form with ifix}(T) \leqslant n^{4/9}$ . This builds on earlier work Burness Thomas, who studied case where ...

OBJECTIVE To document the involution rate and long-term results of management of multicystic dysplastic kidney. MATERIALS AND METHODS Data were collected retrospectively for all 23 infants (16 boys) with multicystic dysplastic kidney who were treated at our center over the last 19 years (1977-1995). The diagnosis was based on prenatal ultrasound in 18 patients and on palpable abdominal mass i...

Let B be a real 2-block of a finite group G. A defect couple of B is a certain pair (D, E) of 2-subgroups of G, such that D a defect group of B, and D ≤ E. The block B is principal if E = D; otherwise [E : D] = 2. We show that (D, E) determines which B-subpairs are real. The involution module of G arises from the conjugation action of G on its involutions. We outline how (D, E) influences the v...

The objectives of the present study were to determine the time of uterine involution and ovarian activity using ultrasound examination and progesterone assay. Weekly progesterone levels were measured starting one week postpartum until two weeks after the 1(st) postpartum estrus in Barbary ewes lambed during winter in AL-Bayda city, north of Libya. A total of 15 Barbary ewes were used in the pre...

We study the maps induced on cohomology by a Nikulin (i.e. a symplectic) involution on a K3 surface. We parametrize the eleven dimensional irreducible components of the moduli space of algebraic K3 surfaces with a Nikulin involution and we give examples of the general K3 surface in various components. We conclude with some remarks on MorrisonNikulin involutions, these are Nikulin involutions wh...

Distinguished involutions in the affine Weyl groups, defined by G. Lusztig, play an essential role in the Kazhdan-Lusztig combinatorics of these groups. A distinguished involution is called canonical if it is the shortest element in its double coset with respect to the finite Weyl group. Each two-sided cell in the affine Weyl group contains precisely one canonical distinguished involution. In t...

Jeffrey Adams, University of Maryland. The Chevalley Involution for Real Groups, with applications to the Fubini-Schur Indicator. The Chevalley involution of a complex group is unique up to conjugation, and takes any algebraic representation to its contragredient. The analogue over local fields is subtle. We prove that the Chevalley involution is defined over R, and with an appropriate conditio...

Weakly hyperbolic involutions are introduced and a proof is given of the following local-global principle: a central simple algebra with involution of any kind is weakly hyperbolic if and only if its signature is zero for all orderings of the ground field. Also, the order of a weakly hyperbolic algebra with involution is a power of two, this being a direct consequence of a result of Scharlau. A...

In this paper, we construct a lagrangian subspace of the space of representations Mg,l := HomC(πg,l, U)/U of the fundamental group πg,l of a punctured Riemann surface into an arbitrary compact connected Lie group U . This lagrangian subspace is obtained as the fixed-point set of an anti-symplectic involution β̂ defined on Mg,l. We show that the involution β̂ is induced by a form-reversing involut...