OBJECTIVE To report two cases of right crossed non-fused renal ectopia diagnosed in male patients about 30 years of age who arrived to emergency centres with symptoms of renal colic. METHODS We report two cases of male patients who arrived to an emergency centre complaining of colic lumbar pain. Crossed renal ectopia was finally revealed by means of intravenous urogram after several analytica...

Crossed complexes are shown to have an algebra sufficiently rich to model the geometric inductive definition of simplices, and so to give a purely algebraic proof of the Homotopy Addition Lemma (HAL) for the boundary of a simplex. This leads to the fundamental crossed complex of a simplicial set. The main result is a normalisation theorem for this fundamental crossed complex, analogous to the u...

Things should be as simple as possiblèand no simpler', so they say. This paper is about simplifying a construct in Ruby, to reduce the complexity of the algebra without sacriicing expressive power. Ruby, for which Mary Sheeran is largely responsible, is a language of relations and a collection of rules { equalities { for algebraic transformation of expressions in that language. The presentation...

Keratoconus is a non-inflammatory corneal dystrophy in which the cornea deforms due to thinning and protrusion. The biomechanical strength of the cornea depends on the lamellar organization of the collagen fibers that comprise the corneal stroma, regulated by an interconnecting network of proteoglycans. Although the pathogenesis of keratoconus remains unclear, it appears that a primary event le...

In this paper following Conduché’s, [12], way of defining 2-crossed modules which are equivalent to Carrasco-Cegarra’s, [10], 2-hyper crossed complexes, we define the three crossed module of groups as a model for 4-types.

The hypercube parallel architecture is one of the most popular interconnection networks due to many of its attractive properties and its suitability for general purpose parallel processing. An attractive version of the hypercube is the crossed cube. It preserves the important properties of the hypercube and most importantly reduces the diameter by a factor of two. In this paper, we show the abi...

In this study, adhesive wear extension in axisymmetric fretting contacts is simulated by applying the Contact Oxygenation Concept (COC) which illustrates influence of loadings on oxygen transport within interface. Di-oxygen flow modeled using an Advection-Dispersion-Reaction (ADR) approach was formerly proposed assuming third body as a porous medium crossed atmospheric gases. It shown that ADR ...

The construction of magic squares is a complex permutation and combination problem. It very difficult to construct the square with continuous minimum natural number, its solution has nature diversity increases exponentially increase order. In this paper, constructed by selecting specific real numbers in different situations. Firstly, model realized using genetic algorithm, population selected, ...

There is a well-known equivalence between the homotopy types of connected CW-spaces X with πnX=0 for n 6= 1, 2 and the quasi-isomorphism classes of crossed modules ∂ : M → P [16]. When the homotopy groups π1X and π2X are finite one can represent the homotopy type of X by a crossed module in which M and P are finite groups. We define the order of such a crossed module to be |∂| = |M | × |P |, an...

We introduce a more general version of the so-called L-R-smash product and study its relations with other kinds of crossed products (two-sided smash and crossed product and diagonal crossed product).