Any finite set of lines in the real projective plane determines a cell complex; these complexes and their combinatorial properties have been a subject of study at least since 1826 [9]. More recently, Levi [6] considered a topological generalization of this notion, defined as follows: Consider a simple closed curve in RP2 which does not separate RP2; this is called a pseudoline. (It is clear tha...

We introduce a new combinatorial object, the double-permutation sequence, and use it to encode a family of mutually disjoint compact convex sets in the plane in a way that captures many of its combinatorial properties. We use this encoding to give a new proof of the Edelsbrunner-Sharir theorem that a collection of n compact convex sets in the plane cannot be met by straight lines in more than 2...

The Roman imperial monarchy is generally studied from the vantage point of ancient Roman history: the “Roman emperor” is viewed and analyzed as an element of the Roman world. This conventional approach fails to place this institution in a broader comparative context, that of monarchical rulers across world history. Systematic comparison opens up new perspectives and is indispensable in identify...

The practice nursing workforce has grown exponentially in recent years. Whilst evidence has shown the important contributions of nurses to general practice service delivery, the consumer perspective of nursing in general practice has received limited attention. Given that acceptability of nurses is influenced by patient satisfaction which can in turn improve both treatment adherence and clinica...

The antiquities of Jammu and Kashmir reveal that women might have enjoyed a high status as elsewhere in India. But ,there was a marked deterioration in the position of women. Female children were not much desired and their sufferings became endless with the beginning of inroads of Turko-Afghan tribes for whom carrying away of women formed the prized item of booty. This situation gave new dimens...

Manin and Schechtman defined the discriminantal arrangement of a generic hyperplane arrangement as a generalization of the braid arrangement. This paper shows their construction is dual to the fiber zonotope construction of Billera and Sturmfels, and thus makes sense even when the base arrangement is not generic. The hyperplanes, face lattices and intersection lattices of discriminantal arrange...