1,261 research outputs found
Stationary disks and Green functions in almost complex domains
Using generalized Riemann maps, normal forms for almost complex domains (D,
J) with singular foliations by stationary disks are defined. Such normal forms
are used to construct counterexamples and to determine intrinsic conditions,
under which the stationary disks are extremal disks for the Kobayashi metric or
determine solutions to almost complex Monge-Ampere equation.Comment: 25 page
Regularity of Kobayashi metric
We review some recent results on existence and regularity of Monge-Amp\`ere
exhaustions on the smoothly bounded strongly pseudoconvex domains, which admit
at least one such exhaustion of sufficiently high regularity. A main
consequence of our results is the fact that the Kobayashi pseudo-metric k on an
appropriare open subset of each of the above domains is actually a smooth
Finsler metric. The class of domains to which our result apply is very large.
It includes for instance all smoothly bounded strongly pseudoconvex complete
circular domains and all their sufficiently small deformations.Comment: 14 pages, 8 figures - The previously announced main result had a gap.
In this new version the corrected statement is given. To appear on the volume
"Geometric Complex Analysis - Proceedings of KSCV 12 Symposium
AFM and pulsed laser ablation methods for Cultural Heritage: application to archeometric analysis of stone artifacts
Surgical management of penetrating pulmonary injuries
Chest injuries were reported as early as 3000 BC in the Edwin Smith Surgical Papyrus. Ancient Greek chronicles reveal that they had anatomic knowledge of the thoracic structures. Even in the ancient world, most of the therapeutic modalities for chest wounds and traumatic pulmonary injuries were developed during wartime
Risk of cancer after assisted reproduction: a review of the available evidences and guidance to fertility counselors
Infertile women requiring ovarian stimulation and assisted reproduction techniques (ART) are faced with difficult issues. The fear that using hormones could increase their risk of cancer is the most significant. One of the main challenges for assessing cancer risk after ART is the difficulty to separate it from the underlying condition of infertility per se. The delay or the inability to achieve a pregnancy is an important risk factor for breast, endometrial and ovarian cancer. We analyzed the current literature on the topic
0110: Exercise stress echocardiography in secondary mitral regurgitation: impact of pulmonary hypertension
BackgroundSecondary mitral regurgitation (MR) is a serious and frequent complication of dilated cardiomyopathy and/or coronary artery disease. The impact of exerxise pulmonary hypertension (ExPHT) on outcome in patients with secondary MR is unknown.Method and resultsAll patients with secondary MR, sinus rhythms, narrow QRS (<120ms) and referred for exercise stress echocardiography with quantifiable exercise systolic pulmonary arterial pressure (SPAP), were included in this study (n=159, 65±11 years, 66% of male). Resting and ExPHT were defined as a systolic pulmonary arterial pressure (SPAP) >50mmHg and >60mmHg, respectively. ExPHT was more frequent than resting PHT (40% vs. 13%, p<0.0001). There was no significant difference between patients with or without ExPHT regarding demographic and clinical data, as well as medication. Using multiple linear regression, exercise SPAP was determined by resting SPAP (β=0.94±0.1, p<0.0001), exercise MR severity (β=0.58±0.1, p<0.0001), and resting e’-wave velocity (β=–1.3±0.4, p=0.004). During a mean follow-up of 35±11 months, 60 major adverse cardiovascular events occured. The incidence of combined cardiac event was significantly higher in patients with ExPHT as compared to those without ExPHT (2-year: 11±3 vs. 28±6%; 4-year: 20±5 vs. 40±7%, p<0.0001). Similarly, patients with ExPHT demonstrated significantly reduced survival (2-year: 88±4 vs. 99±1%; 4-year: 62±8% vs. 94±2%, p<0.0001). In multivariate Cox proportional Hazard model, after adjustment for age, sex, left ventricular volumes, both resting and exercise diastolic function and resting MR severity, ExPHT remains significantly associated with high risk of combined cardiac event (Hazard ratio=3.7, 95% of CI: 1.9-7.2, p<0.0001).ConclusionIn patients with secondary MR, ExPHT may be frequent and mainly determined by resting SPAP, LV diastolic burden markers and exercise MR severity. ExPHT is a powerful predictor of poor outcome and is associated with a 3.7-fold increase in risk of cardiac event. These results further highlight the usefulness of exercise stress echocardiography for the management and the risk stratification of these patients
Polymeric surfactants for enhanced oil recovery:A review
AbstractChemical enhanced oil recovery (EOR) is surely a topic of interest, as conventional oil resources become more scarce and the necessity of exploiting heavy and unconventional oils increases. EOR methods based on polymer flooding, surfactant-polymer flooding and alkali-surfactant-polymer flooding are well established, but new challenges always emerge, which give impulse to the search for new solutions. Polymeric surfactants represent a very attractive alternative to these techniques, because they can provide simultaneously increase in water viscosity and decrease in interfacial tension, both beneficial for the efficiency of the process. The analysis of the literature shows that the use of polymeric surfactants as displacing fluid has the potential to improve the performances of EOR in some cases. However, the synthesis are often challenging and costly and the available data about the real performances of such systems in oil recovery are still sparse. This holds back the possibility of a significant use of polymeric surfactants for EOR. This review collects the relevant work done in the last decades in developing and testing polymeric surfactants for EOR, with a particular emphasis on the chemical aspects, the patent literature and bio-based systems
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