429 research outputs found
The stochastic renormalized mean curvature flow for planar convex sets
We investigate renormalized mean curvature flow (RMCF) and stochastic
renormalized mean curvature flow (SRMCF) for convex sets in the plane.RMCF is
the inverse gradient flow for logarithm of square of the perimeter divided by
the volume. SRMCF is We investigate renormalized mean curvature flow (RMCF) and
stochastic renormalized mean curvature flow (SRMCF) for convex sets in the
plane. RMCF is the inverse gradient flow for logarithm of
where is the perimeter and is the volume. SRMCF is RMCF
perturbated by some Brownian noise and has the remarkable property that it can
be intertwined with Brownian motion, yielding a generalization of Pitman
"" theorem. We prove that along RMCF, entropy for
curvature as well as are non-increasing. We deduce
infinite lifetime and convergence to a disk after normalization. For SRMCF the
situation is more complicated. As is always a supermartingale, for
to be a supermartingale, we need that the starting set is
invariant by the isometry group generated by the reflection with respect
to the vertical line and the rotation of angle , for some . But
for proving infinite lifetime, we need invariance of the starting set by
for some . We provide the first SRMCF with infinite lifetime which
cannot be reduced to a finite dimensional flow. Gage inequality plays a major
role in our study of the regularity of flows, as well as a careful
investigation of morphological skeletons. We characterize symmetric convex sets
with star shaped skeletons in terms of properties of their Gauss map. Finally,
we establish a new isoperimetric estimate for these sets, of order
where is the number of branches of the skeleton
HASAR : mining sequential association rules for atherosclerosis risk factor analysis
International audienceWe present the HASAR method that is an hybrid approach for ex- tracting adaptive sequential association rules. This method extracts association rules between events occurring in subsequent time-intervals using closed itemsets extraction and evolutionary techniques. An important feature is its capacity to consider different time-intervals depending on the attributes semantic. We applied this method for the analysis of long term medical observations of atherosclerosis risk factors for cardio-vascular diseases prevention. Experimental results show that it is well-suited for extracting knowledge from temporal data where interesting patterns have different observation period length.Nous prĂ©sentons la mĂ©thode HASAR qui est une approche hybride pour lÂextraction de rĂšgles dÂassocations sĂ©quentilles. Cette mĂ©thode extrait des rĂšgles association entre des Ă©vĂšnements ayant lieu Ă diffĂ©rent moment en extrayant des itemsets fermĂ©s frĂ©quents et en utilisant des techniques Ă©volutionnaires. Une fonctionnalitĂ© important de notre mĂ©thode est sa capacitĂ© Ă sÂadapter Ă diffĂ©rente Ă©chelle de temps en fonction de la sĂ©mantique des attributs. Nous avons appliquĂ© cette mĂ©thode pour analyser des observations mĂ©dicales Ă long terme sur les facteurs de risques de lÂartherosclerose. Les rĂ©sultats expĂ©rimentaux ont montrĂ© que cette mĂ©thode est bien adaptĂ©e pour extraire des connaissance Ă partir de donnĂ©es temporelles ou les motifs intĂ©ressants doivent ĂȘtre observĂ©s sur diffĂ©rentes pĂ©riodes de temps
On the evolution by duality of domains on manifolds
On a manifold, consider an elliptic diffusionXadmitting an invariant measureÎŒ. The goalof this paper is to introduce and investigate the first properties of stochastic domain evolutionspDtqtPr0,Ïswhich are intertwining dual processes forX(whereÏis an appropriate positive stoppingtime before the potential emergence of singularities). They provide an extension of Pitmanâstheorem, as it turns out thatpÎŒpDtqqtPr0,Ïsis a Bessel-3 process, up to a natural time-change.WhenXis a Brownian motion on a Riemannian manifold, the dual domain-valued process is astochastic modification of the mean curvature flow to which is added an isoperimetric ratio driftto prevent it from collapsing into singletons
Prologue
Quâest-ce quâune « prise de parole publique » aujourdâhui ? Quelles sont ses diverses formes possibles, leurs modalitĂ©s, leur efficacitĂ©Â ? Le problĂšme sâinscrit dans la perspective qui fut toujours celle de Labyrinthe, soit la rĂ©flexion sur le devenir des savoirs â tous les savoirs, et de tous ordres â dans lâespace public. Ă lâorigine du prĂ©sent dossier, il y avait aussi une difficultĂ© intime, pour nous, Ă trouver une voix propre dans la cacophonie ambiante. Mais au-delĂ dâun souci personnel..
Lâinterruption politique
RP Jâaurais quelques questions sur le projet gĂ©nĂ©ral de LâEmpire du langage : tu dis, Laurent, vouloir « interroger les diffĂ©rentes maniĂšres quâa le langage de transmettre â ou dĂ©mettre â lâordre social et politique », la littĂ©rature occupant une place de choix (du cĂŽtĂ© du « dĂ©mettre ») dans cet Ă©ventail de « maniĂšres ». Or tu as toujours Ă©tĂ© rĂ©ticent, câest un euphĂ©misme, devant le nouage littĂ©rature-politique : je me souviens bien de nos dĂ©bats sur RanciĂšre, dont tu ne goĂ»tais pas les propo..
Positive Outcomes of HAART at 24 Months in HIV-Infected Patients in Cambodia.
OBJECTIVES: African and Asian cohort studies have demonstrated the feasibility and efficacy of HAART in resource-poor settings. The long-term virological outcome and clinico-immunological criteria of success remain important questions. We report the outcomes at 24 months of antiretroviral therapy (ART) in patients treated in a MĂ©decins Sans FrontiĂšres/Ministry of Health programme in Cambodia. METHODS: Adults who started HAART 24 +/- 2 months ago were included. Plasma HIV-RNA levels were assessed by real-time polymerase chain reaction. Factors associated with virological failure were analysed using logistic regression. RESULTS: Of 416 patients, 59.2% were men; the median age was 33.6 years. At baseline, 95.2% were ART naive, 48.9% were at WHO stage IV, and 41.6% had a body mass index less than 18 kg/m. The median CD4 cell count was 11 cells/microl. A stavudine-lamivudine-efavirenz-containing regimen was initiated predominantly (81.0%). At follow-up (median 23.8 months), 350 (84.1%) were still on HAART, 53 (12.7%) had died, six (1.4%) were transferred, and seven (1.7%) were lost to follow-up. Estimates of survival were 85.5% at 24 months. Of 346 tested patients, 259 (74.1%) had CD4 cell counts greater than 200 cells/microl and 306 (88.4%) had viral loads of less than 400 copies/ml. Factors associated with virological failure at 24 months were non-antiretroviral naive, an insufficient CD4 cell gain of less than 350 cells/microl or a low trough plasma ART concentration. In an intention-to-treat analysis, 73.6% of patients were successfully treated. CONCLUSION: Positive results after 2 years of advanced HIV further demonstrate the efficacy of HAART in the medium term in resource-limited settings
Stereotactic Re-irradiation for Local Recurrence in the Prostatic Bed After Prostatectomy: Preliminary Results
Objectives: To report the preliminary results of salvage re-irradiation in the prostatic bed after radical prostatectomy and salvage external beam radiation therapy (EBRT) using robotic stereotactic body radiation therapy (SBRT) with CyberknifeÂź for local recurrence of prostate cancer.Materials and Methods: Retrospective monocentric analysis was performed on patients treated with SBRT for isolated macroscopic recurrence in the prostatic bed. All patients had radical prostatectomy and salvage or adjuvant EBRT. Local recurrence was documented using magnetic resonance imaging (MRI) and positron emission tomography (PET). Biochemical recurrence was defined as 2 rises in prostate-specific antigen (PSA) of â„ 0.2 ng/mL above nadir. Internal gold fiducials were used for the tracking of tumor motion during SBRT. The prescription dose was 36 Gy in 6 fractions for all patients. Toxicity was scored according to the CTCAE v4.0.Results: Between July 2011 and November 2017, 12 patients were treated with SBRT for prostatic bed recurrence with a median follow-up of 34.2 (range, 3.5â64.4) months. Isolated non-metastatic recurrence in the prostatic bed was seen at MRI and PET imaging. Two patients were treated with 6 months androgen deprivation therapy (ADT) concomitant with re-irradiation. The median planning target volume was 4.5 cm3 (range, 1.2â13.3). A PSA decrease after SBRT was found in 10 (83%) patients. The 1 and 2 years biochemical recurrence-free survival rates were 79 and 56%, respectively. Biochemical recurrence was observed for 6 patients (50%) after a median time of 18 (4-42) months. Toxicity showed: 3 patients (25%) with grade 1 cystitis and 1 patient (8%) with acute grade 2 proctitis at 4 months. One patient (13%) had grade 1 cystitis at 12 months.Conclusion: Re-irradiation for local recurrence in the prostatic bed using CyberknifeÂź after surgery and salvage or adjuvant EBRT is well-tolerated and associated with 2 years biochemical recurrence-free survival rates of 56%. Longer follow-up and larger series are necessary
Utero-vaginal aplasia (Mayer-Rokitansky-KĂŒster-Hauser syndrome) associated with deletions in known DiGeorge or DiGeorge-like loci
<p>Abstract</p> <p>Background</p> <p>Mayer-Rokitansky-KĂŒster-Hauser (MRKH) syndrome is characterized by congenital aplasia of the uterus and the upper part of the vagina in women showing normal development of secondary sexual characteristics and a normal 46, XX karyotype. The uterovaginal aplasia is either isolated (type I) or more frequently associated with other malformations (type II or MĂŒllerian Renal Cervico-thoracic Somite (MURCS) association), some of which belong to the malformation spectrum of DiGeorge phenotype (DGS). Its etiology remains poorly understood. Thus the phenotypic manifestations of MRKH and DGS overlap suggesting a possible genetic link. This would potentially have clinical consequences.</p> <p>Methods</p> <p>We searched DiGeorge critical chromosomal regions for chromosomal anomalies in a cohort of 57 subjects with uterovaginal aplasia (55 women and 2 aborted fetuses). For this candidate locus approach, we used a multiplex ligation-dependent probe amplification (MLPA) assay based on a kit designed for investigation of the chromosomal regions known to be involved in DGS.</p> <p>The deletions detected were validated by Duplex PCR/liquid chromatography (DP/LC) and/or array-CGH analysis.</p> <p>Results</p> <p>We found deletions in four probands within the four chromosomal loci 4q34-qter, 8p23.1, 10p14 and 22q11.2 implicated in almost all cases of DGS syndrome.</p> <p>Conclusion</p> <p>Uterovaginal aplasia appears to be an additional feature of the broad spectrum of the DGS phenotype. The DiGeorge critical chromosomal regions may be candidate loci for a subset of MRKH syndrome (MURCS association) individuals. However, the genes mapping at the sites of these deletions involved in uterovaginal anomalies remain to be determined. These findings have consequences for clinical investigations, the care of patients and their relatives, and genetic counseling.</p
A comparative descriptive analysis of perceived quality of caring attitudes and behaviours between haemodialysis patients and their nurses
Despite its importance in nursing, perceived quality of the nurse-patient relationship has seldom been researched. This study sought to examine and compare the quality of caring attitudes and behaviours as perceived by haemodialysis patients and their nurses. Design This comparative descriptive study involved 140 haemodialysis patients and 101 nurses caring for them in ten haemodialysis units in the French-speaking part of Switzerland. Methods Participants completed a sociodemographic questionnaire and the Caring Nurse-Patient Interaction Scale (CNPI-70). Results Both nurses and patients reported a high frequency of caring attitudes and behaviours. Patients gave higher ratings than nurses did on all the caring dimensions, except spirituality. Implications are discussed
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