Canal wall up tympanoplasty for middle ear cholesteatoma in adults: Modeling cartilage

SummaryObjectivesThe authors report their experience with a variant cartilage tympanoplasty technique in a canal wall up (CWU) procedure for middle ear cholesteatoma, comparing reliability with other techniques. Functional results are analyzed according to ossicular chain status.Materials and methodsA retrospective study was performed in adults operated on with CWU tympanoplasty for middle ear cholesteatoma. The surgical technique of “modeling” cartilage is described.ResultsOne hundred and nine patients were included (113 procedures). There were four recurrences (3.5%). Mean follow-up was 48 months (range, 24–96 months). In case of normal ossicular chain, postoperative pure-tone average air-bone gap was always less than 20dB, and less than 20dB following myringostapedopexy in 60% of cases with incus destruction.ConclusionModeling cartilage is a reliable reconstruction technique to prevent recurrent cholesteatoma, and contributes to the quality of functional results in ossiculoplasty

relax: the analysis of biomolecular kinetics and thermodynamics using NMR relaxation dispersion data

International audienceNuclear Magnetic Resonance (NMR) is a powerful tool for observing the motion of biomolecules at the atomic level. One technique, the analysis of relaxation dispersion phenomenon, is highly suited for studying the kinetics and thermodynamics of biological processes. Built on top of the relax computational environment for NMR dynamics is a new dispersion analysis designed to be comprehensive, accurate and easy to use. The software supports more models, both numeric and analytic, than current solutions. An automated protocol, available for scripting and driving the GUI, is designed to simplify the analysis of dispersion data for NMR spectroscopists. Decreases in optimisation time are granted by parallelisation for running on computer clusters and by skipping an initial grid search by using parameters from one solution as the starting point for another – using analytic model results for the numeric models, taking advantage of model nesting, and using averaged non-clustered results for the clustered analysis. Availability: The software relax is written in Python with C modules and is released under the GPLv3+ licence. Source code and precompiled binaries for all major operating systems are available from http://www.nmr-relax.com

relax: the analysis of biomolecular kinetics and thermodynamics using NMR relaxation dispersion data

Nuclear magnetic resonance (NMR) is a powerful tool for observing the motion of biomolecules at the atomic level. One technique, the analysis of relaxation dispersion phenomenon, is highly suited for studying the kinetics and thermodynamics of biological processes. Built on top of the relax computational environment for NMR dynamics is a new dispersion analysis designed to be comprehensive, accurate and easy-to-use. The software supports more models, both numeric and analytic, than current solutions. An automated protocol, available for scripting and driving the graphical user interface (GUI), is designed to simplify the analysis of dispersion data for NMR spectroscopists. Decreases in optimization time are granted by parallelization for running on computer clusters and by skipping an initial grid search by using parameters from one solution as the starting point for another —using analytic model results for the numeric models, taking advantage of model nesting, and using averaged non-clustered results for the clustered analysis. Availability and implementation: The software relax is written in Python with C modules and is released under the GPLv3+ license. Source code and precompiled binaries for all major operating systems are available from http://www.nmr-relax.com. Contact: [email protected]

Changing indications and socio-demographic determinants of (adeno)tonsillectomy among children in England--are they linked? A retrospective analysis of hospital data.

OBJECTIVE: To assess whether increased awareness and diagnosis of obstructive sleep apnoea syndrome (OSAS) and national guidance on tonsillectomy for recurrent tonsillitis have influenced the socio-demographic profile of children who underwent tonsillectomy over the last decade. METHOD: Retrospective time-trends study of Hospital Episodes Statistics data. We examined the age, sex and deprivation level, alongside OSAS diagnoses, among children aged <16 years who underwent (adeno)tonsillectomy in England between 2001/2 and 2011/12. RESULTS: Among children aged <16 years, there were 29,697 and 27,732 (adeno)tonsillectomies performed in 2001/2 and 2011/12, respectively. The median age at (adeno)tonsillectomy decreased from 7 (IQR: 5-11) to 5 (IQR: 4-9) years over the decade. (Adeno)tonsillectomy rates among children aged 4-15 years decreased by 14% from 350 (95%CI: 346-354) in 2001/2 to 300 (95%CI: 296-303) per 100,000 children in 2011/12. However, (adeno)tonsillectomy rates among children aged <4 years increased by 58% from 135 (95%CI: 131-140) to 213 (95%CI 208-219) per 100,000 children in 2001/2 and 2011/2, respectively. OSAS diagnoses among children aged <4 years who underwent surgery increased from 18% to 39% between these study years and the proportion of children aged <4 years with OSAS from the most deprived areas increased from 5% to 12%, respectively. CONCLUSIONS: (Adeno)tonsillectomy rates declined among children aged 4-15 years, which reflects national guidelines recommending the restriction of the operation to children with more severe recurrent throat infections. However, (adeno)tonsillectomy rates among pre-school children substantially increased over the past decade and one in five children undergoing the operation was aged <4 years in 2011/12.The increase in surgery rates in younger children is likely to have been driven by increased awareness and detection of OSAS, particularly among children from the most deprived areas

Homeomorphic Embedding for Online Termination of Symbolic Methods

Well-quasi orders in general, and homeomorphic embedding in particular, have gained popularity to ensure the termination of techniques for program analysis, specialisation, transformation, and verification. In this paper we survey and discuss this use of homeomorphic embedding and clarify the advantages of such an approach over one using well-founded orders. We also discuss various extensions of the homeomorphic embedding relation. We conclude with a study of homeomorphic embedding in the context of metaprogramming, presenting some new (positive and negative) results and open problems

The coinductive formulation of common knowledge

We study the coinductive formulation of common knowledge in type theory. We formalise both the traditional relational semantics and an operator semantics, similar in form to the epistemic system S5, but at the level of events on possible worlds rather than as a logical derivation system. We have two major new results. Firstly, the operator semantics is equivalent to the relational semantics: we discovered that this requires a new hypothesis of semantic entailment on operators, not known in previous literature. Secondly, the coinductive version of common knowledge is equivalent to the traditional transitive closure on the relational interpretation. All results are formalised in the proof assistants Agda and Coq

Formally validated specification of a micro-payment protocol

In this paper, we develop a formal specification for a micro-payment protocol, first on paper, then within the Coq proof assistant. Our approach in defining a notion of execution traces for protocol runs is inspired by previous works, notably by L. Paulson (in the Isabelle/HOL System). However, we show that the protocol we study entails some modifications to Pailson's frameword, related to the modeling of the agents' internal state. We moreover take profit from Coq's expressive meta-language to mechanically derive proofs bout the formalisation itself, by introducing a notion a well-formedness for protocol rulesCet article présente la spécification formelle d'un protocole de micro-paiement d'abord par une définition sur papier, puis par une formalisation dans l'assistant à la preuve Coq. Nous nous inspirons d'une méthode employée principalement par L. Paulson afin d'introduire une notion de trace pour les exécutions du protocole que nous étudions.Néanmoins, le traitement du protocole en question rend nécessaires quelques modifications à l'approche de Paulson, en rapport avec la modélisation de l'état interne des agents. Nous exploitons le cadre formel fourni par Coq pour valider la spécification qui 'est faire en prouvant des propriétés de la spécification proposée, propriétés qui s’expriment çà travers une notion de bonne formation des règles définissant les étapes du protocol

Formally validated specification of a micro-payment protocol

In this paper, we develop a formal specification for a micro-payment protocol, first on paper, then within the Coq proof assistant. Our approach in defining a notion of execution traces for protocol runs is inspired by previous works, notably by L. Paulson (in the Isabelle/HOL System). However, we show that the protocol we study entails some modifications to Pailson's frameword, related to the modeling of the agents' internal state. We moreover take profit from Coq's expressive meta-language to mechanically derive proofs bout the formalisation itself, by introducing a notion a well-formedness for protocol rulesCet article présente la spécification formelle d'un protocole de micro-paiement d'abord par une définition sur papier, puis par une formalisation dans l'assistant à la preuve Coq. Nous nous inspirons d'une méthode employée principalement par L. Paulson afin d'introduire une notion de trace pour les exécutions du protocole que nous étudions.Néanmoins, le traitement du protocole en question rend nécessaires quelques modifications à l'approche de Paulson, en rapport avec la modélisation de l'état interne des agents. Nous exploitons le cadre formel fourni par Coq pour valider la spécification qui 'est faire en prouvant des propriétés de la spécification proposée, propriétés qui s’expriment çà travers une notion de bonne formation des règles définissant les étapes du protocol