A discrete-pulse optimal control algorithm with an application to spin systems

This article is aimed at extending the framework of optimal control techniques to the situation where the control field values are restricted to a finite set. We propose a generalization of the standard GRAPE algorithm suited to this constraint. We test the validity and the efficiency of this approach for the inversion of an inhomogeneous ensemble of spin systems with different offset frequencies. It is shown that a remarkable efficiency can be achieved even for a very limited number of discrete values. Some applications in Nuclear Magnetic Resonance are discussed

Advances in the medical management of bowel endometriosis

Endometriosis infiltrating the bowel can be treated medically in accurately selected women not seeking conception and without overt obstructive symptomatology. When the rectosigmoid junction is involved, the probabilities of intestinal symptoms relief, undergoing surgery after treatment failure, and developing bowel obstruction during hormonal treatment are around 70%, 10%, and 1-2%, respectively. When the lesion infiltrates exclusively the mid-rectum, thus in cases of true rectovaginal endometriosis, the probabilities of intestinal symptoms relief and undergoing surgery are about 80% and 3%, respectively. Endometriotic obstructions of the rectal ampulla have not been reported. A rectosigmoidoscopy or colonoscopy should be performed systematically before starting medical therapies, also to rule out malignant tumours arising from the intestinal mucosa. Progestogens are safe, generally effective, well-tolerated, inexpensive, and should be considered as first-line medications for bowel endometriosis. Independently of symptom relief, intestinal lesions should be checked periodically to exclude nodule progression during hormonal treatment

Reperfusion therapy in renal dysfunction patients presenting with STEMI: Which is better in the Tunisian context?

BackgroundPatients with renal insufficiency experience worse prognosis after STEMI. Current guidelines do not clearly draw specific strategies for renal dysfunction (RD) patients, and most clinical trials exclude them from the study population.Aim of the studyTo compare primary PCI (PPCI) and thrombolysis (using Strepokinase) results as well as in-hospital mortality after successful reperfusion between patients with or without RD.MethodsFrom January 1995 to October 2011, 1388 patients admitted for STEMI were enrolled in the MIRAMI (MonastIR’s Acute Myocardial Infarction) registry. Two reperfusion groups were identified: PPCI (315 patients) and thrombolysis (379 patients). Patients who underwent rescue PCI were excluded. Due to lacking clearance data, we used a serum creatinine level >130μmol/l to define RD patients. We compared in each reperfusion group: (1) The success of revascularization (TIMI III flow restoring with <20% residual stenosis after PPCI, pain relief with ST regression >50% 60min after thrombolysis) and (2) the in-hospital mortality rate after reperfusion success between the RD patients (RD+) and normal renal function patients (RD−).ResultsNinety patients (13%) had RD, 50% of which underwent PPCI, and 50% received thrombolytics. Among RD+ and RD- groups, baseline characteristics were similar between the two reperfusion groups.In the PPCI group, although TIMI flow was similar before angioplasty (p=0.82), TIMI III restoring was significantly lower in the RD+ group (78.6% vs 91.8%, p=0.013). Suboptimal result was also higher in the RD+ group (13.6% vs 2.7%, p<0.001), but ST regression after TIMI III achievement was similar in the 2 groups (p=0.43) reflecting probably no microvascular damage.In the thrombolysis group, successful reperfusion was also significantly lower when RD exists (58% vs 74%, p=0.03).After successful reperfusion, in-hospital mortality is higher among RD+ patients in the PPCI group (33.3% vs 4.3%, p<0.001), whereas it is similar after successful thrombolysis (2.6% vs 0%, p=0.42).ConclusionRD reduces either PPCI or thrombolysis success, with no proven microvascular damage after PPCI. In-hospital prognosis is however worse in RD group only after successful PPCI, but not after successful Streptokinase thrombolysis

La déhiscence du canal semi circulaire supérieur

Introduction : Superior semicircular canal dehiscence is a rare entity witch is recently described. The common symptom is pressure-induced vertigo.Patients and methods: we report 2 cases of superior semicircular canal dehiscence identified by computed tomography (CT) of the petrous bone in patients with mixed hearing loss and a normal tympanic membrane.Results: Superior semicircular canal dehiscence was bilateral in 1 patient.Mixed hearing loss with a normal tympanic membrane without vertigo was the presenting manifestation in all cases. Ultrahigh-resolution CT of the petrous bones with coronal and sagittal sections provided the diagnosis of superior semicircular canal dehiscence.Conclusion: Mixed hearing loss with a normal tympanic membrane should suggest superior semi circular canal dehiscence. Coronal and sagittal CT sections less than 1 mm in thickness establish the diagnosis.Key words : Superior semicircular canal, dehiscence, hearing loss

Hematome organise du sinus maxillaire a propos d’un cas

L’hématome organisé du sinus maxillaire est une entité rare. Son étiopathogénie reste incertaine. Nous rapportons le cas d’une patiente âgée de 16 ans présentant une épistaxis unilatérale droite de grande abondance avec une endoscopie nasale strictement normale. L’imagerie était en faveur d’une tumeur vasculaire du sinus maxillaire. Une exérèse chirurgicale complète a été réalisée par voie combinée avec des suites simples. L’examen anatomopathologique a conclu à un hématome organisé du sinus maxillaire. Nous discutons, dans ce travail, l’étiopathogénie, les caractéristiques cliniques, radiologiques et les volets thérapeutiques de cette entité.Mots clés : Hématome organisé, sinus maxillaire, tomodensitométrie, chirurgie

Measurement of the (90,91,92,93,94,96)Zr(n,gamma) and (139)La(n,gamma) cross sections at n_TOF

Open AccessNeutron capture cross sections of Zr and La isotopes have important implications in the field of nuclear astrophysics as well as in the nuclear technology. In particular the Zr isotopes play a key role for the determination of the neutron density in the He burning zone of the Red Giant star, while the (139)La is important to monitor the s-process abundances from Ba up to Ph. Zr is also largely used as structural materials of traditional and advanced nuclear reactors. The nuclear resonance parameters and the cross section of (90,91,92,93,94,96)Zr and (139)La have been measured at the n_TOF facility at CERN. Based on these data the capture resonance strength and the Maxwellian-averaged cross section were calculated

Measurements of high-energy neutron-induced fission of (nat)Pb and (209)Bi

This is an Open Access article distributed under the terms of the Creative Commons Attribution-Noncommercial License 3.0, which permits unrestricted use, distribution, and reproduction in any noncommercial medium, provided the original work is properly citedThe CERN Neutron Time-Of-Flight (n_TOF) facility is well suited to measure low cross sections as those of neutron-induced fission in subactinides. The cross section ratios of (nat)Pb and (209)Bi relative to (235)U and (238)U were measured using PPAC detectors and a fragment coincidence method that allows us to identify the fission events. The present experiment provides first results for neutron-induced fission up to 1 GeV. Good agreement is found with previous experimental data below 200 MeV. The comparison with proton-induced fission indicates that the limiting regime where neutron-induced and proton-induced fission reach equal cross sections is close to 1 GeV

Equivalence classes of the second order ODEs with the constant Cartan invariant

Second order ordinary differential equations that possesses the constant invariant are investigated. Four basic types of these equations were found. For every type the complete list of nonequivalent equations is issued. As the exampes the equivalence problem for the Painleve II equation, Painleve III equation with three zero parameters, Emden equations and for some other equations is solved

Measurement of the neutron capture cross section of the s-only isotope 204Pb from 1 eV to 440 keV

The neutron capture cross section of 204Pb has been measured at the CERN n_TOF installation with high resolution in the energy range from 1 eV to 440 keV. An R-matrix analysis of the resolved resonance region, between 1 eV and 100 keV, was carried out using the SAMMY code. In the interval between 100 keV and 440 keV we report the average capture cross section. The background in the entire neutron energy range could be reliably determined from the measurement of a 208Pb sample. Other systematic effects in this measurement could be investigated and precisely corrected by means of detailed Monte Carlo simulations. We obtain a Maxwellian average capture cross section for 204Pb at kT=30 keV of 79(3) mb, in agreement with previous experiments. However our cross section at kT=5 keV is about 35% larger than the values reported so far. The implications of the new cross section for the s-process abundance contributions in the Pb/Bi region are discussed.Comment: 8 pages, 3 figures, article submitted to Phys. Rev.