Ricerc@Sapienza

As part of a wider enquiry on the historical typologies of architectural
representation, this essay addresses a classification of XVI century architecture
drawings that exploit the presence of one or more symmetry axes in the
represented building. This kind of split drawings have never been studied as a
specific group of works inspired by the specific peculiarities of buildings but
only occasionally to mark a new role of architectural drawing. Actually, symmetry
combined to orthogonal projections allowed the development of graphic

Morse index of solutions of semilinear elliptic equations : definition, computation and applications

We consider the Lane-Emden problem in the unit ball B of ℝ^2 centered at the origin with Dirichlet boundary conditions and exponent ∈(1,+∞) of the power nonlinearity. We prove the existence of sign-changing solutions having 2 nodal domains, whose nodal line does not touch ∂ and which are non-radial. We call these solutions quasi-radial. The result is obtained for any p sufficiently large, considering least energy nodal solutions in spaces of functions invariant under suitable dihedral groups of symmetry and proving that they fulfill the required qualitative properties.

Visual working memory exhibits age effects that are amongst the largest observed in the cognitive aging literature. In this research we investigated whether or not older adults can benefit from visual symmetry and semantic availability, as young adults typically do. Visual matrix pattern tasks varied in terms of the perceptual factor of symmetry (Experiment 1), as well as the availability of visual semantics, or long-term memory (LTM; Experiment 2).

Two experiments investigated the effects of pointing movements on the item and order recall of random, horizontal and vertical arrays consisting of 6 and 7 squares (Experiment 1) or 8 and 9 squares (Experiment 2). In the encoding phase, participants either viewed the items passively (passive-view condition) or pointed towards them (pointing condition). Then, after a brief interval, they were requested to recall the locations of the studied squares in the correct order of presentation.