Survivability in hierarchical telecommunications networks

Abstract We consider the problem of designing a two level telecommunications network at minimum cost. The decisions involved are the locations of concentrators, the assignments of user nodes to concentrators and the installation of links connecting concentrators in a reliable backbone network. We define a reliable backbone network as one where there exist at least 2-edge disjoint paths between any pair of concentrator nodes. We formulate this problem as an integer program and propose a facial study of the associated polytope. We describe valid inequalities and give sufficient conditions for these inequalities to be facet defining. We also propose some reduction operations in order to speed up the separation procedures for these inequalities. Using these results, we devise a branch-and-cut algorithm and present some computational results

Vulnerability assessment of spatial networks: models and solutions

In this paper we present a collection of combinatorial optimization problems that allows to assess the vulnerability of spatial networks in the presence of disruptions. The proposed measures of vulnerability along with the model of failure are suitable in many applications where the consideration of failures in the transportation system is crucial. By means of computational results, we show how the proposed methodology allows us to find useful information regarding the capacity of a network to resist disruptions and under which circumstances the network collapses

Disentangling molecular and clinical stratification patterns in beta-galactosidase deficiency

INTRODUCTION: This study aims to define the phenotypic and molecular spectrum of the two clinical forms of β-galactosidase (β-GAL) deficiency, GM1-gangliosidosis and mucopolysaccharidosis IVB (Morquio disease type B, MPSIVB). METHODS: Clinical and genetic data of 52 probands, 47 patients with GM1-gangliosidosis and 5 patients with MPSIVB were analysed. RESULTS: The clinical presentations in patients with GM1-gangliosidosis are consistent with a phenotypic continuum ranging from a severe antenatal form with hydrops fetalis to an adult form with an extrapyramidal syndrome. Molecular studies evidenced 47 variants located throughout the sequence of the GLB1 gene, in all exons except 7, 11 and 12. Eighteen novel variants (15 substitutions and 3 deletions) were identified. Several variants were linked specifically to early-onset GM1-gangliosidosis, late-onset GM1-gangliosidosis or MPSIVB phenotypes. This integrative molecular and clinical stratification suggests a variant-driven patient assignment to a given clinical and severity group. CONCLUSION: This study reports one of the largest series of b-GAL deficiency with an integrative patient stratification combining molecular and clinical features. This work contributes to expand the community knowledge regarding the molecular and clinical landscapes of b-GAL deficiency for a better patient management

Survivability in hierarchical telecommunications networks

International audienceWe consider the problem of designing a two level telecommunications network at minimum cost. The decisions involved are the locations of concentrators, the assignments of user nodes to concentrators and the installation of links connecting concentrators in a reliable backbone network. We define a reliable backbone network as one where there exist at least 2-edge disjoint paths between any pair of concentrator nodes. We formulate this problem as an integer program and propose a facial study of the associated polytope. We describe valid inequalities and give sufficient conditions for these inequalities to be facet defining. We also propose some reduction operations in order to speed up the separation procedures for these inequalities. Using these results, we devise a branch-and-cut algorithm and present some computational results

Neurological manifestations in adults with phenylketonuria: new cases and review of the literature

Early Access: NOV 2019International audienceOBJECTIVE: Phenylketonuria (PKU) is a rare autosomal recessive disease characterised by high plasma phenylalanine levels inducing, if untreated, serious neurological manifestations in children but also, rarely, in adults who stopped their diet. The objective of the study was to describe the neurological manifestations observed in adults with PKU. METHODS: We analysed cases reported in French reference centres for inborn errors of metabolism and cases already reported in the literature. RESULTS: We report 8 new cases of neurological manifestations and 22 cases in the literature, which occurred in adult PKU patients, associated with chronic or rapid increase of phenylalanine levels, mostly when strict low-phenylalanine diet was stopped early in life. Neurological symptoms consisted in cerebellar ataxia, tremor, brisk reflexes, visual loss, sensory manifestations, and/or headaches. Visual loss was more frequent in the new cases (4/8) of the present series than in the literature (4/22). These neurological complications were associated with leucopathy on brain magnetic resonance imaging (27/29). The start of a low-phenylalanine diet improved or fully reversed neurological manifestations, even in patients with late diagnosis during adulthood. CONCLUSION: Neurological manifestations can complicate PKU in adult patients with elevated phenylalanine levels, after long or short period of diet discontinuation. Neurologists should be aware of this diagnosis, and measure phenylalaninemia in case of neurological symptoms associated with non-specific leucopathy on brain MRI. PKU patients should be systematically encouraged to continue their diet and their medical follow-up to avoid neurological complications

Fiabilité des réseaux de télécommunications hiérarchiques

National audienc

Influenza burden in children newborn to eleven months of age in a pediatric emergency department during the peak of an influenza epidemic.

BACKGROUND: The aim of this study was to determine the burden of influenza-related diseases in children 0 to 11 months of age during the peak of the 2001 to 2002 influenza epidemic. METHODS: This was a prospective study at the Pediatric Emergency Department of Edouard Herriot tertiary teaching hospital in Lyon, France. The study included 304 infants 0 to 11 months of age. Consecutive patients were systematically enrolled during the 4 weeks of the influenza epidemic peak (Weeks 3 to 6, 2002). Influenza viruses were detected by antigen detection and virus culture from nasal swabs. Structured telephone interviews were conducted on Days 8 and 15 after virus detection. There was also a 6-month survey into the medicoadministrative database to detect late complications that required delayed hospitalization of influenza-positive children. RESULTS: Influenza virus was detected in 99 (33%) of 304 patients (A/H3N2 in 30% and B in 3%). Nonrespiratory symptoms were the dominant clinical manifestations in 30% of influenza-positive children. One child with influenza presented with febrile seizures. Twenty (20%) children with influenza were hospitalized. Parents reported recovery from the illness in 63 and 94% of children on Days 8 and 15, respectively. The median length of an influenza episode was 8 days. CONCLUSIONS: Our results confirm the high prevalence of influenza-related morbidity in infants during the epidemic peak. One child in three consulting to the pediatric emergency room had a virologically confirmed influenza infection regardless of the body temperature. Every fifth child with influenza was admitted to hospital, which corresponds to an admission rate of 237 per 100 000 children 0 to 11 months of age