We investigate criteria to relate specifications and implementations belonging to conceptually different levels of abstraction. For this purpose, we introduce the generic concept of a vertical implementation relation, which is a family of binary relations indexed by a refinement function that maps abstract actions onto concrete processes and thus determines the basic connection between the abst...

BACKGROUND AND AIM The aim of our study is to analyze the different techniques used in arthroscopic treatment of talus osteochondral lesions. MATERIAL AND METHOD We retrospectively analyzed 73 patients who underwent surgery between 2000 and 2011. Patients were divided in two groups: group A (51 patients), those treated with osteochondral stimulation techniques, and group B (32 patients), that...

We are searching for an unknown horizontal or vertical line in the plane under the competitive framework. We design a well-suited framework for all cylcic strategies that result in two-sequence functionals. For optimizing such functionals we apply a method that combines two main paradigms. The given solution shows that the combination method is of general interest. Finally, we obtain the curren...

The Darwinian concept of biological evolution assumes that life on Earth shares a common ancestor. The diversification of this common ancestor through speciation events and vertical transmission of genetic material implies that the classification of life can be illustrated in a tree-like manner, commonly referred to as the Tree of Life. This article describes features of the Tree of Life, such ...

A SIR epidemic model with delay, saturated contact rate and vertical transmission is considered. The basic reproduction number 0 R is calculated. It is shown that this number characterizes the disease transmission dynamics: if 0 1 R , there only exists the disease-free equilibrium which is globally asymptotically stable; if 0 1 R , there is a unique endemic equilibrium and the disease persists,...

The main combinatorial result in this article is a classification of bar partitions of n which are of maximal p-bar weight for all odd primes p ≤ n. As a consequence, we show that apart from very few exceptions any irreducible spin character of the double covers of the symmetric and alternating groups vanishes on some element of odd prime order.

Mode-division multiplexing (MDM) can increase the capacity of direct-detection short-reach systems in proportion to the number of modes employed. MDM requires compensation of modal crosstalk at a transmitter or receiver by the multi-input multi-output (MIMO) signal processing. We show that the channel estimation required for the MIMO processing in a basis of modes can be expressed as a phase re...

In a visual search task, subjects detected the presence of a target (long vertical line) among distractors that differed in length, orientation, or both. Distractors were designed to model the random variability found in naturalistic data by having them vary normally around the mean distractor. As predicted, adding variability to distractors eliminated popout by increasing reaction times and se...

BACKGROUND A validated scale is needed for objective and reproducible comparisons of chin appearance before and after chin augmentation in practice and clinical studies. OBJECTIVE To describe the development and validation of the 5-point photonumeric Allergan Chin Retrusion Scale. METHODS The Allergan Chin Retrusion Scale was developed to include an assessment guide, verbal descriptors, mor...

A stochastic model for the evolution of a growing population is proposed, in order to explain empirical power-law distributions in the frequency of family names as a function of the family size. Preliminary results show that the predicted exponents are in good agreement with real data. The evolution of family-name distributions is discussed in the frame of vertical transmission of cultural feat...