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In this paper we address the problem of picking a subset of bids in a general combinatorial auction so as to maximize the overall profit using the first-price model. This winner determination problem assumes that a single bidding round is held to determine both the winners and prices to be paid. We introduce six variants of biased random-key genetic algorithms for this problem. Three of them use a novel initialization technique that makes use of solutions of intermediate linear programming relaxations of an exact mixed integer linear programming model as initial chromosomes of the population. An experimental evaluation compares the effectiveness of the proposed algorithms with the standard mixed linear integer programming formulation, a specialized exact algorithm, and the best-performing heuristics proposed for this problem. The proposed algorithms are competitive and offer strong results, mainly for large-scale auctions.

We report a 3-year-old female with type I spinal muscular atrophy (SMA) born to a young and non-consanguineous couple. The child presented at two months of life with intense muscle weakness affecting predominantly proximal portions of the limbs, especially the legs, muscle hypotonia, fasciculation of the tongue, and severe respiratory muscle involvement. She remained in an intensive care unit with an assisted ventilation system from the fourth month of life. She died at 3 years of age from pulmonary infection. Molecular analysis confirmed the diagnosis of SMA but revealed that only the father was an asymptomatic carrier. Because SMN1 is mapped in a complex region containing repetitive elements due to an inverted duplication of approximately 500 kb, we carry out an SNP array and detected a 1.3 Mb deletion including the SMN1 and SMN2 genes that explain the disease., (Copyright © 2013 Elsevier B.V. All rights reserved.)

This paper describes the applicability of a Hg-electroplated-Pt ultramicroelectrode in the quantification of elemental sulphur in naphtha samples by square-wave voltammetry. A reproducible deposition methodology was studied and is reported in this paper. This methodology is innovative and relies on the quality of the mercury stock solution to obtain reproducible surfaces required for the analytical methodology. All analyses were performed using a Hg-electroplated-Pt ultramicroelectrode (Hg-Pt UME) due to the low sensibility of such devices to ohmic drops in resistive solutions. The responses of the peak areas in voltammetric experiments were linear in all of the range studied. The method developed here is accurate and reproducible, with a detection limit of 0.010 mg L(-1) and a good recovery range for both standard solutions of elemental sulphur (85 to 99%) and real naphtha sample (79%). These results attest to the potential for the application of this electroanalytical methodology in determining elemental sulphur in naphtha samples containing mercaptans and disulphides.

Robinow syndrome is a genetically heterogeneous condition characterized by mesomelic limb shortening associated with facial and genital anomalies that can be inherited in an autosomal dominant or recessive mode. We characterized these two variants clinically, with the aim of establishing clinical criteria to enhance the differential diagnosis between them or other similar conditions. The frequencies of clinical signs considered important for the discrimination of the dominant or recessive variants were estimated in a sample consisting of 38 patients personally examined by the authors and of 50 affected subjects from the literature. Using the presence of rib fusions as diagnostic of the recessive variant, and also based on the inheritance pattern in familial cases, we classified 37 patients as having the recessive form and other 51 as having the dominant form. The clinical signs present in more than 75% of patients with either form, and therefore the most important for the characterization of this syndrome were hypertelorism, nasal features (large nasal bridge, short upturned nose, and anteverted nares), midface hypoplasia, mesomelic limb shortening, brachydactyly, clinodactyly, micropenis, and short stature. Hemivertebrae and scoliosis were present in more than 75% of patients with the recessive form, but in less than 25% of patients with the dominant form. Umbilical hernia (32.3%) and supernumerary teeth (10.3%) were found exclusively in patients with the dominant form., ((c) 2007 Wiley-Liss, Inc.)