Dilatation de la racine aortique mesurée par échographie cardiaque et Imagerie par Résonance Magnétique (IRM) après intervention de Ross

Introduction - Les atteintes congénitales de la valve aortique sont les valvulopathies les plus fréquentes de l'enfant et du jeune adulte. Lors de sténose ou d'insuffisance aortique symptomatique, l'indication à un remplacement valvulaire est posée. Les bioprothèses aortiques ont une durée de vie limitée et les valves mécaniques nécessitent une anticoagulation à vie. De plus, leur potentiel de croissance est nul, ce qui pose problème chez les patients n'ayant pas atteint la taille adulte lors de l'intervention. L'opération de Ross a été développée pour pallier aux inconvénients précités. Elle consiste à remplacer la valve aortique défectueuse par la propre valve du patient (autogreffe valvulaire pulmonaire), à la place de laquelle le chirurgien installe une bioprothèse valvulaire. La dilatation progressive de la racine aortique, pouvant mener à une insuffisance valvulaire aortique, est une complication connue après l'intervention de Ross. Nous avons voulu démontrer dans cette étude la fréquence de cette complication, et nous avons comparé les mesures faite par échographie cardiaque et par imagerie par résonance magnétique (IRM) Méthodologie - Sur les 63 patients opérés d'un Ross entre le 1er janvier 1990 et le 31 décembre 2010, 31 sont suivis au CHUV en cardiologie pédiatrique ou à la consultation des cardiopathies congénitales à l'âge adulte. Nous avons comparé les mesures de racine aortique sur l'échographie cardiaque faite en postopératoire immédiat et sur l'échographie cardiaque la plus récente en date du 1 septembre 2015. Chez 55% des patients (17/31 patients), nous avons également comparé les mesures d'IRM et d'échographie cardiaque. Résultats - Pour 16% des patients (5/31) l'indication opératoire était la sténose aortique, pour 29% (9/31) l'insuffisance aortique et 55% (17/31) avaient une maladie aortique associant sténose et insuffisance. L'âge moyen au moment de la chirurgie était de 13.23 ans, allant de l'âge de 2 à 38 ans, avec 65% (20/31) des patients de sexe masculin. Le temps de suivi allait de 0 à 17 ans, avec un temps de suivi moyen de 7.45 ans Il n'y a eu aucun décès durant notre période de suivi. 68% des patients (21/31) présentaient une dilatation de la racine aortique avec un diamètre moyen de 41.57 +/- 7.15 mm (n = 26) soit 23.01 +/- 3.18 mm/m2 pour une norme à 19 +/- 1 mm/m2 à la dernière échographie (p-value <0.001) et de 42.47 +/- 3.50 mm (n = 15) à la dernière IRM (p-value <0.001), avec une différence entre les deux modalités de mesures non-significative (p-value >0.05). Les patients ayant une dilatation ne présentaient pas d'association significative avec une insuffisance aortique (p-value >0.05). Au total, 6 patients ont dû être réopérés, 16% des patients (5/31) pour une dysfonction de l'homogreffe, 6% (2/31) pour une dysfonction de la néovalve aortique. Conclusions - L'opération de Ross est une alternative à la mise en place d'une prothèse valvulaire aortique (mécanique ou biologique) pour les patients présentant une valvulopathie aortique sévère, en particulier chez les jeunes patients. La dilatation progressive de la racine aortique est très fréquente dans cette population et doit motiver une adaptation des techniques opératoires, ainsi qu'une nécessité de suivi rapproché

Phenomenology on the QCD dipole picture revisited

We perform an adjust to the most recent structure function data, considering the QCD dipole picture applied to ep scattering. The structure function F2 at small x and intermediate Q2 can be described by the model containing an economical number of free-parameters, which encodes the hard Pomeron physics. The longitudinal structure function and the gluon distribution are predicted without further adjustments. The data description is effective, whereas a resummed next-to-leading level analysis is deserved.Comment: 18 pages, 6 figures. Version to be published in Eur. Phys. J.

Performa Pertumbuhan Indigofera zollingeriana pada Media Tanam yang Berbeda di Sulawei Tengah

Potensi hijauan pakan ternak (HPT) unggul di Sulawesi Tengah perlu lakukan sebuah pengembangan secara masif sehingga penyebaran HPT utamanya legum dapat merata di wilayah Sulawesi Tengah. Masih minimnya informasi terkait dengan persemian legum Indigofera Zollingeriana. di media tanam yang berbeda khususnya di Sulawesi Tengah menjadi tantangan untuk pengembangan legum serta terbatasnya kebun induk bibit. Tantangan ini dapat dijawab dengan pengembangan HPT unggul salah satu yang cukup potensional adalah tanaman legume. Indigofera S.p sangat cocok dengan topografi, mikroklimat serta kondisi lingkungan di Sulawesi Tengah.Penelitian ini bertujuan untuk mengkaji performa pertumbuhan Indigofera Zollingerianapada media tanam yang berbeda di Sulawesi Tengah.Hasil penelitian memperlihatkan jumlah daun, batang dan tinggi pada setiap perlakukan, Perlakuan P3 memperlihatkan hasil yang terbaik dibandingkan yang lainya. Hasil dari penelitian diharapkan dijadikan rujukan rekomendasi alternatif solusi terhadap permasalahan keterbatasan di Sulawesi Tengah khususnya di peternakan rakyat

Validity of the Brunet-Derrida formula for the speed of pulled fronts with a cutoff

We establish rigorous upper and lower bounds for the speed of pulled fronts with a cutoff. We show that the Brunet-Derrida formula corresponds to the leading order expansion in the cut-off parameter of both the upper and lower bounds. For sufficiently large cut-off parameter the Brunet-Derrida formula lies outside the allowed band determined from the bounds. If nonlinearities are neglected the upper and lower bounds coincide and are the exact linear speed for all values of the cut-off parameter.Comment: 8 pages, 3 figure

Industrial applicability of advanced model/code-based V&V techniques for verifying program properties in embedded applications

International audienceThe constant and significant increase of computer power at low cost and many recent major technologicaladvances in program properties verification techniques show that designers and developers can now efficientlyand practically use proving techniques either at model or source code level.Those new V&V techniques convey major benefits to industrial sectors where software quality is at stake includingearly detection of errors (at specification, design and coding levels), and proof of absence of errors. Thosetechniques strengthen software application development process and minimize the likelihood of errors foundeither late or released in the field.The paper describes several advanced techniques for statically verifying dynamic properties of programsincluding logical, functional, run-time errors, how those techniques fit within current development processes andhow they may be used for monitoring software quality over time. The paper primarily applies to the developmentof embedded applications and demonstrates how the combined usage of techniques such as model-checking andabstract interpretation effectively handles industrial problems today

Hamiltonian solutions of the 3-body problem in (2+1)-gravity

We present a full study of the 3-body problem in gravity in flat (2+1)-dimensional space-time, and in the nonrelativistic limit of small velocities. We provide an explicit form of the ADM Hamiltonian in a regular coordinate system and we set up all the ingredients for canonical quantization. We emphasize the role of a U(2) symmetry under which the Hamiltonian is invariant and which should generalize to a U(N-1) symmetry for N bodies. This symmetry seems to stem from a braid group structure in the operations of looping of particles around each other, and guarantees the single-valuedness of the Hamiltonian. Its role for the construction of single-valued energy eigenfunctions is also discussed.Comment: 25 pages, no figure. v2: some calculation details removed to make the paper more concise (see v1 for the longer version), minor correction in a formula in the section on quantization, references added; results and conclusions unchange

Universality and tree structure of high energy QCD

Using non-trivial mathematical properties of a class of nonlinear evolution equations, we obtain the universal terms in the asymptotic expansion in rapidity of the saturation scale and of the unintegrated gluon density from the Balitsky-Kovchegov equation. These terms are independent of the initial conditions and of the details of the equation. The last subasymptotic terms are new results and complete the list of all possible universal contributions. Universality is interpreted in a general qualitative picture of high energy scattering, in which a scattering process corresponds to a tree structure probed by a given source.Comment: 4 pages, 3 figure

Effect of selection on ancestry: an exactly soluble case and its phenomenological generalization

We consider a family of models describing the evolution under selection of a population whose dynamics can be related to the propagation of noisy traveling waves. For one particular model, that we shall call the exponential model, the properties of the traveling wave front can be calculated exactly, as well as the statistics of the genealogy of the population. One striking result is that, for this particular model, the genealogical trees have the same statistics as the trees of replicas in the Parisi mean-field theory of spin glasses. We also find that in the exponential model, the coalescence times along these trees grow like the logarithm of the population size. A phenomenological picture of the propagation of wave fronts that we introduced in a previous work, as well as our numerical data, suggest that these statistics remain valid for a larger class of models, while the coalescence times grow like the cube of the logarithm of the population size.Comment: 26 page

Intracameral Chemotherapy (Melphalan) for Aqueous Seeding in Retinoblastoma: Bicameral Injection Technique and Related Toxicity in a Pilot Case Study.

The anterior chamber has been shown by pharmacokinetic studies to represent a sanctuary never achieving a tumoricidal dose with the present administration routes, such as systemic, intra-arterial, or intravitreal injections. A novel intracameral chemotherapy technique is described to control aqueous seeding in a pilot unilateral group E retinoblastoma case with primary aqueous seeding. Anterior segment toxicity was carefully monitored. Control of the retinal tumor and vitreous seeding was achieved by intra-arterial and intravitreal chemotherapies. Sterilization of the aqueous was achieved after a first cycle of 7 melphalan injections in the anterior chamber, but relapse was noted 3.5 months later. This relapse was finally controlled with a second cycle of 6 intracameral injections targeting the posterior chamber. Corneal endothelial cell density remained stable over the injection period. Heterochromia and a progressive cataract developed, which required cataract surgery. At 5 years' follow-up, the patient is tumor free with normal vision (20/20 in both eyes), full binocularity, and no metastasis. The present bicameral injection technique appears to be safe and effective with limited toxicity. Melphalan-induced side effects were noted on the iris and lens but with no impact on the final visual function

A phenomenological theory giving the full statistics of the position of fluctuating pulled fronts

We propose a phenomenological description for the effect of a weak noise on the position of a front described by the Fisher-Kolmogorov-Petrovsky-Piscounov equation or any other travelling wave equation in the same class. Our scenario is based on four hypotheses on the relevant mechanism for the diffusion of the front. Our parameter-free analytical predictions for the velocity of the front, its diffusion constant and higher cumulants of its position agree with numerical simulations.Comment: 10 pages, 3 figure