INTRODUCTION Rotary nickel-titanium instruments have multiple advantages but with the risk of more fractures because of flexure or torsion. Alternating rotation appears to be an alternative to continuous rotary movement. The objective of this study was to determine the influence of the type of instrument rotation on the frequency of fractures or deformation. METHODS Instrumentation was perfor...

introduction: the aim of this study was to verify the effect of alternating 2.5% sodium hypochlorite (naocl) and 17% ethylenediaminetetraacetic acid (edta) on the smear layer removal from root canal surfaces. methods and materials: a total of 15 single-rooted human teeth, instrumented with protaper files, were randomly distributed in 3 groups. in group 1 ( n =7) the canals were irrigated with 1...

We provide two sufficient conditions to guarantee that the round functions of a translation based cipher generate a primitive group. Furthermore, under the same hypotheses, and assuming that a round of the cipher is strongly proper and consists of m-bit S-Boxes, with m = 3,4 or 5, we prove that such a group is the alternating group. As an immediate consequence, we deduce that the round function...

The automorphism group of a binary doubly-even self-dual code is always contained in the alternating group. On the other hand, given a permutation group G of degree n there exists a doubly-even self-dual G-invariant code if and only if n is a multiple of 8, every simple self-dual F2G-module occurs with even multiplicity in F n 2 , and G is contained in the alternating group.

Unramified coverings of the affine line in characteristic two are constructed having alternating groups as Galois groups. The proof uses Jacobson’s criterion for the Galois group of an equation to be contained in the alternating group. Alternative proofs use the Berlekamp discriminant or the Revoy discriminant. These are related to the Arf invariant.

for some n , acting primitively on the set of vertices. This forms a part of the programme for the classification of all finite primitive distance transitive graphs begun in [76]; for in [76] this classification is reduced to the determination of all such graphs whose automorphism group G is either almost simple (that is, T o f f S Aut T for some nonabelian simple group T ) or affine (that is, ...

The results in the paper exclude several thinkable regularities of the SERPENT round functions. Thus they support the statement of the SERPENT authors that this algorithm has strong cryptographic properties.

The canonical transformation diagonalizing the one-particle tight binding Hamiltonian for an alternating chain with two non-equivalent sites per unit cell has been used to introduce the Hubbard-like interactions (on-site, intersite, bond-site and intra-bond) in the corresponding two-band model. The considerations have been restricted to the particular case, suggested by the undistorted 3/4-fill...

In this paper, two different ways of introducing alternation for lattice-valued (referred to as {L}valued)  regular tree grammars and {L}valued top-down tree automata are compared. One is the way which defines the alternating regular tree grammar, i.e., alternation is governed by the non-terminals of the grammar and the other is the way which combines state with alternation. The first way is ta...