Search results for " Primary"

Periodic measures and partially hyperbolic homoclinic classes

2019

In this paper, we give a precise meaning to the following fact, and we prove it: $C^1$-open and densely, all the non-hyperbolic ergodic measures generated by a robust cycle are approximated by periodic measures. We apply our technique to the global setting of partially hyperbolic diffeomorphisms with one dimensional center. When both strong stable and unstable foliations are minimal, we get that the closure of the set of ergodic measures is the union of two convex sets corresponding to the two possible $s$-indices; these two convex sets intersect along the closure of the set of non-hyperbolic ergodic measures. That is the case for robustly transitive perturbation of the time one map of a tr…

Hyperbolicity as an obstruction to smoothability for one-dimensional actions

2017

Ghys and Sergiescu proved in the $80$s that Thompson's group $T$, and hence $F$, admits actions by $C^{\infty}$ diffeomorphisms of the circle . They proved that the standard actions of these groups are topologically conjugate to a group of $C^\infty$ diffeomorphisms. Monod defined a family of groups of piecewise projective homeomorphisms, and Lodha-Moore defined finitely presentable groups of piecewise projective homeomorphisms. These groups are of particular interest because they are nonamenable and contain no free subgroup. In contrast to the result of Ghys-Sergiescu, we prove that the groups of Monod and Lodha-Moore are not topologically conjugate to a group of $C^1$ diffeomorphisms. Fur…

Entropy, Lyapunov exponents, and rigidity of group actions

2018

This text is an expanded series of lecture notes based on a 5-hour course given at the workshop entitled "Workshop for young researchers: Groups acting on manifolds" held in Teres\'opolis, Brazil in June 2016. The course introduced a number of classical tools in smooth ergodic theory -- particularly Lyapunov exponents and metric entropy -- as tools to study rigidity properties of group actions on manifolds. We do not present comprehensive treatment of group actions or general rigidity programs. Rather, we focus on two rigidity results in higher-rank dynamics: the measure rigidity theorem for affine Anosov abelian actions on tori due to A. Katok and R. Spatzier [Ergodic Theory Dynam. Systems…

La termoablazione nel trattamento delle neoplasie epatiche primitive e secondarie

2004

Radiofrequency thermoablation is a locoregional procedure based on the use of electromagnetic waves that induce movement and consequently the production of heat. This is the basis for the coagulative necrosis produced in the tissues. The method, experimented with and developed in the '90s, is today extensively used in the treatment of focal hepatic lesions, both primary and secondary. The factors that condition the procedure are related essentially to the characteristics of the tumours and to the possibility of obtaining a predictable area of necrosis that guarantees the radicality of the treatment. As regards primary neoplasms, it should be stressed that the treatment for hepatocellular ca…

Years of life that could be saved from prevention of hepatocellular carcinoma

2016

Summary Background Hepatocellular carcinoma (HCC) causes premature death and loss of life expectancy worldwide. Its primary and secondary prevention can result in a significant number of years of life saved. Aim To assess how many years of life are lost after HCC diagnosis. Methods Data from 5346 patients with first HCC diagnosis were used to estimate lifespan and number of years of life lost after tumour onset, using a semi-parametric extrapolation having as reference an age-, sex- and year-of-onset-matched population derived from national life tables. Results Between 1986 and 2014, HCC lead to an average of 11.5 years-of-life lost for each patient. The youngest age-quartile group (18–61 y…

Imperative and Elective Indications for Nephron-Sparing Surgery for Renal Tumors: Long-Term Oncological Follow-Up

2010

INTRODUCTION: Nephron-sparing surgery (NSS) is mandatory for patients with renal tumors in both kidneys or in a solitary kidney in order to preserve renal function (imperative indication). NSS has also become the gold standard (elective indication) for small unilateral renal tumors (< 4 cm) with a normal contralateral kidney. We report the oncological long-term follow-up of NSS of our own series and discuss the results of the current literature. PATIENTS AND METHODS: From 1979 until 2006, a total of 851 patients was treated at our institu-tion by NSS. The mean tumor diameter was 3 cm (0.5-11 cm) for elective cases and 4.2 cm (1.2-11 cm) for imperative cases. The median follow-up for electiv…

Human, Technologies and Quality of Education, 2022: Proceedings of Scientific Papers

2022

Locally nilpotent derivations of rings graded by an abelian group

2019

International audience

TRACE Analysis of the MASLWR Primary/Containment Coupling Phenomena in Beyond Design Accident Scenario

2013

Emotional Competence in Primary School Children: Examining the Effect of a Psycho-Educational Group Intervention: A Pilot Prospective Study

2022

Emotional competence (EC) is a key component of children’s psychological, cognitive, and social development, and it is a central element of learning. The primary goal of this study was to evaluate the effectiveness of implementing a psycho-educational group intervention aimed at improving children’s emotional competence (EC), quality of integration and scholastic skills. A total of 229 children (123 females; M Age = 7.22 years; SD = 0.97 years) completed the Pictures of Facial Affect (POFA), the Drawn Stories Technique, the Classroom Drawing, and the Colored Progressive Matrices. The total sample was randomly divided into an intervention group (N = 116) who took part in psycho-educational a…