Long time, large scale limit of the Wigner transform for a system of linear oscillators in one dimension

We consider the long time, large scale behavior of the Wigner transform W_\eps(t,x,k) of the wave function corresponding to a discrete wave equation on a 1-d integer lattice, with a weak multiplicative noise. This model has been introduced in Basile, Bernardin, and Olla to describe a system of interacting linear oscillators with a weak noise that conserves locally the kinetic energy and the momentum. The kinetic limit for the Wigner transform has been shown in Basile, Olla, and Spohn. In the present paper we prove that in the unpinned case there exists $\gamma_0>0$ such that for any $\gamma\in(0,\gamma_0]$ the weak limit of W_\eps(t/\eps^{3/2\gamma},x/\eps^{\gamma},k), as \eps\ll1, satisfies a one dimensional fractional heat equation $\partial_t W(t,x)=-\hat c(-\partial_x^2)^{3/4}W(t,x)$ with $\hat c>0$. In the pinned case an analogous result can be claimed for W_\eps(t/\eps^{2\gamma},x/\eps^{\gamma},k) but the limit satisfies then the usual heat equation

Cut Points and Diffusions in Random Environment

In this article we investigate the asymptotic behavior of a new class of multi-dimensional diffusions in random environment. We introduce cut times in the spirit of the work done by Bolthausen, Sznitman and Zeitouni, see [4], in the discrete setting providing a decoupling effect in the process. This allows us to take advantage of an ergodic structure to derive a strong law of large numbers with possibly vanishing limiting velocity and a central limit theorem under the quenched measure.Comment: 44 pages; accepted for publication in "Journal of Theoretical Probability

Safety and feasibility of robotic-assisted drainage of symptomatic pancreatic pseudocysts: A case-series analysis (with video)

The surgical treatment of pancreatic pseudocysts (PPs) in patients who fail nonoperative management has evolved from aggressive open to a minimally invasive approach. The application of robotic surgery in this setting is scarcely reported. The aim of this study is to analyze the safety and feasibility of the robotic approach to pancreatic pseudocyst drainage. A single centre retrospective review of consecutive patients undergoing robotic-assisted pancreatic pseudocyst surgeries in an academic tertiary institution was performed. There were 14 patients studied, of whom 10 underwent cystogastrostomy and 4 Roux-En-Y cystojejunostomy. Eight patients had gallstone pancreatitis and 3 patients alcoholic pancreatitis. The mean size of cyst was 8.9±1cm and 57.1% located at the pancreatic body. The overall operative time of the procedure was 135±34 minutes. There were no open conversions. The overall success rate was 92.8%, while the primary success rate 85.7%. The major morbidity rate was 14.3% and there was no 30-day mortality. The mean post-operative hospital stay was 7±3 days with one recurrence of the pancreatic pseudocyst on follow-up requiring endoscopic drainage without further recurrence. The robotic approach for the drainage of symptomatic pancreatic pseudocyst is safe and feasible and can be considered as a viable modality for operative intervention in well-selected patient

Aluminum-, Calcium- And Titanium-Rich Oxide Stardust In Ordinary Chondrite Meteorites

We report isotopic data for a total of 96 presolar oxide grains found in residues of several unequilibrated ordinary chondrite meteorites. Identified grain types include Al2O3, MgAl2O4, hibonite (CaAl12O19) and Ti oxide. This work greatly increases the presolar hibonite database, and is the first report of presolar Ti oxide. O-isotopic compositions of the grains span previously observed ranges and indicate an origin in red giant and asymptotic giant branch (AGB) stars of low mass (<2.5 MSun) for most grains. Cool bottom processing in the parent AGB stars is required to explain isotopic compositions of many grains. Potassium-41 enrichments in hibonite grains are attributable to in situ decay of now-extinct 41Ca. Inferred initial 41Ca/40Ca ratios are in good agreement with model predictions for low-mass AGB star envelopes, provided that ionization suppresses 41Ca decay. Stable Mg and Ca isotopic ratios of most of the hibonite grains reflect primarily the initial compositions of the parent stars and are generally consistent with expectations for Galactic chemical evolution, but require some local interstellar chemical inhomogeneity. Very high 17O/16O or 25Mg/24Mg ratios suggest an origin for some grains in binary star systems where mass transfer from an evolved companion has altered the parent star compositions. A supernova origin for the hitherto enigmatic 18O-rich Group 4 grains is strongly supported by multi-element isotopic data for two grains. The Group 4 data are consistent with an origin in a single supernova in which variable amounts of material from the deep 16O-rich interior mixed with a unique end-member mixture of the outer layers. The Ti oxide grains primarily formed in low-mass AGB stars. They are smaller and rarer than presolar Al2O3, reflecting the lower abundance of Ti than Al in AGB envelopes.Comment: Accepted for publication in ApJ; 47 pages, 13 figure

Invariant, super and quasi-martingale functions of a Markov process

We identify the linear space spanned by the real-valued excessive functions of a Markov process with the set of those functions which are quasimartingales when we compose them with the process. Applications to semi-Dirichlet forms are given. We provide a unifying result which clarifies the relations between harmonic, co-harmonic, invariant, co-invariant, martingale and co-martingale functions, showing that in the conservative case they are all the same. Finally, using the co-excessive functions, we present a two-step approach to the existence of invariant probability measures

Prognostic value of microsatellite instability in adjuvant treatment of colorectal cancer

The dynamics of morbidity and mortality in colorectal cancer (CRC) has changed little in recent years and consistently remains at a high level. The carcinogenesis of this type of tumors includes a large number of genetic disorders and epigenetic changes, which show a number of features specific for this nosology, providing the basis for the first consensus classification of molecular subtypes for colorectal cancer. One of the main mechanisms chosen as crucial for this classification is the microsatellite instability (MSI) caused by defects in the DNA Mismatch Repair System (MMR). The clinical significance of this CRC molecular profile parameter is hard to overestimate. Over the past three decades, the MSI and MMR have been actively studied for prognosis evaluation, determination of need and selection of appropriate adjuvant chemotherapy scheme for CRC. Despite the significant accumulation of clinical and experimental study data, currently the prognostic value of this parameter is still not well defined with reference to CRC adjuvant treatment strategies, and the released data remain controversial. The purpose of this analytic review is to analyze the current status of MSI and MMR in the setting of adjuvant treatment of CRC patients from a perspective of evidence-based medicine

The amino acid and hydrocarbon contents of the Paris meteorite: Insights into the most primitive CM chondrite

International audienc

Specializing Interpreters using Offline Partial Deduction

We present the latest version of the Logen partial evaluation system for logic programs. In particular we present new binding-types, and show how they can be used to effectively specialise a wide variety of interpreters.We show how to achieve Jones-optimality in a systematic way for several interpreters. Finally, we present and specialise a non-trivial interpreter for a small functional programming language. Experimental results are also presented, highlighting that the Logen system can be a good basis for generating compilers for high-level languages