186,233 research outputs found
Optimal decay of p-Sobolev extremals on Carnot groups
No full textWe determine the sharp asymptotic behavior at infinity of solutions to quasilinear critical problems involving the p-sublaplacian operator Delta(p,G) on a Carnot group G, 1 < p < Q. As a remarkable consequence, we obtain the exact rate of decay of the extremal functions for the subelliptic Sobolev inequality involving the L-p-norm of the horizontal gradient
Existence results for critical problems involving p-sub-Laplacians on Carnot groups
No full textWe provide existence results for the quasilinear
subelliptic Dirichlet problem
-\Delta_{p, \mathbb{G}}u = |u|^{p^*-2}u + g(\xi, u) \quad \mbox{in}\,
\Omega,\quad u\in S_0^{1,p}(\Omega), where
is the -sub-Laplacian on a Carnot group
, is the critical Sobolev exponent in
this context, is a bounded domain of and
is a subcritical perturbation. By means of standard
variational methods adapted to the stratified context, we prove
the existence of solutions both in the mountain pass and in the
linking case. A crucial ingredient in this abstract framework is
the knowledge of the exact rate of decay of the -Sobolev
extremals
on Carnot groups
AlphaScope vs lens-based hysteroscope for office polypectomy without anesthesia: randomized controlled study.
No full textIn this randomized controlled study, effectiveness, operative time, and acceptability of endometrial polypectomy were compared using an AlphaScope vs an office operative lens-based hysteroscope (LBH). One hundred fifty women with a diagnosis of endometrial polyp were operated on using an AlphaScope or LBH in the office setting. In 73 procedures using the AlphaScope (97.3%) and 68 using the LBH (90.7%), the polyp was successfully removed completely. In the AlphaScope group, 2 procedures were incomplete because of excessive endometrial mucosa thickness. In the LBH group, 3 procedures were incomplete because of difficulty in management of a large polyp, and 4 procedures were stopped because of patient pain and low compliance. Time to completion of the procedure and complete removal of the polyp was significantly shorter in the AlphaScope group than in the LBH group (p < .05). Similarly, the pain score at the end of the procedure was significantly lower in the AlphaScope group than in the LBH group (p < .05). The AlphaScope is an effective operative hysteroscope that increases the possibility of performing endometrial polypectomy in the office setting without anesthesia and improves the indications for and acceptability of office hysteroscopy
Endovascular treatment of chronic hemoptysis in patients with pulmonary tuberculosis
No full textBackground: We aimed to demonstrate the safety and efficacy of bronchial artery embolization (BAE) in patients with pulmonary tuberculosis in the planned management of “mild” hemoptysis. This treat-ment, already widely documented and used as a life-saving therapy in an emergency regimen, if properly planned in poorly controlled patients through medical therapy alone, can provide a valid opportunity by reducing the frequency and extent of non-fatal bleeding, but which still worsen the quality of life of these already significantly traumatized patients. Methods: All procedures were conducted through a right common femoral access with a 5 Fr catheter and a 2.7 Fr super-selective catheter coaxial technique of the branches of the bronchial arteries with suspected bleeding sources. Embolizations were performed with 500-700 micron Terumo PVA plastic microparticles. We decided to adopt the following inclusion criteria for the selection of patients to be enrolled: documented diagnosis of pulmonary TB, the presence of at least one bleeding epi-sode that required at least two blood transfusions, evaluation with bronchoscopic examination to ascertain the bronchial origin of bleeding and the affected lobar site, execution of an angio-ct radiological study for the evaluation of the bronchial systemic anatomy as well as the patency of the pulmonary arterial circulation, general hemodynamic compensation and an age of enrollment between 25 and 65 years. Results: All selective embolization interventions demonstrated a technical success of 100% of the total number of patients. 11 out of 12 patients did not show any signs of relapse or complications related to the interventional procedure at a first check-up carried out at 48 hours, instead a fatal massive hemoptysis occurred in only one patient. At the next three-month follow-up, no relapses were documented in all selected patients. Only one patient required a second embolization four months after the first procedure. Conclusions: Radiological-interventional approach in the elective regimen of super-selective embolization of the bronchial arteries (BAE) in the management and control of “mild” hemoptysis in patients with pulmonary tuberculosis not controlled exclusively by medical therapy, according to a strategy systematic of planned intervention and respecting clear and standardized inclusion criteria, represented in our experience a safe and effective procedure, free from significant short and long term complications, especially in well selected patients, which, although not always allows a definitive and stable control of hemoptysis, can in any case significantly limit the risks, also allowing a better planning of the most appropriate therapeutic intervention strategy
Strumenti per il raggiungimento delle coperture vaccinali, verifica della qualità delle prestazioni e valutazione dei programmi vaccinali
No full textPerformances Evaluation of Active Filters for Compensation of Distorted Line Currents Produced by Induction Motor Drives
No full textLocal peribulbar anesthesia before glaucoma filtering surgery in a patient with Brugada syndrome
No full textWe report anesthetic management in a patient with Brugada syndrome, an inherited syndrome characterized by normal QT interval, typical ST-segment–elevation in the right precordial leads, and increased risk of sudden cardiac death in the absence of myocardial ischemia or structural heart disease. A 69-year-old man scheduled for glaucoma filtering surgery underwent local peribulbar anesthesia using 5 mL of lidocaine 20 mg/mL solution that was slowly injected into two different sites approximately 10 min prior to the surgical procedure. The surgery proceeded uneventful and data of patient’s blood pressure, heart rate, oxygen saturation were collected. Continuous electrocardiography monitoring before, during, and up to 6 h after surgery did not reveal any arrhythmia or tachycardia. A certain number of drugs should be avoided in patients with Brugada syndrome because of their potential risk to trigger an arrhythmia. Among them there are some anesthetics and in particular those that are sodium channel blockers. Ropivacaine and bupivacaine, commonly used for peribulbar block, have been associated with onset of severe arrhythmias. Contrarily, the use of class IB drugs mexiletine and lidocaine is generally considered safe. Local anesthetic agent should be carefully chosen, and anesthesia should be obtained using the minimal necessary drug dose
Trabeculectomy Versus EX-PRESS Shunt Versus Ahmed Valve Implant: Short-term Effects on Corneal Endothelial Cells
No full textPurpose To evaluate short-term changes in corneal endothelial cells after trabeculectomy, EX-PRESS device implantation, and Ahmed valve implantation for the treatment of primary open-angle glaucoma. Design Prospective, interventional, comparative case series with contralateral eye control study. Methods We prospectively evaluated the changes in number, density, and shape of the corneal endothelium cells in 128 eyes of 64 patients divided into 3 groups depending on the treatment received. Corneal specular microscopy was performed with a noncontact specular microscope preoperatively and at 1 and 3 months after surgery. The changes at each time point were compared with those of the control group, which consisted of 32 contralateral glaucomatous eyes receiving antiglaucoma medications without any previous glaucoma surgery. Results In the subjects who underwent trabeculectomy, corneal endothelial cell density (ECD) significantly decreased by 3.5% (P =.012, paired t test) at 1 month and 4.2% (P =.007) at 3 months after surgery, compared to the baseline values. In the Ahmed valve group ECD did not change at 1 month after surgery and had a significant 3.5% decrease at 3 months (P =.04). In the patients who underwent EX-PRESS implantation and in the control group ECD did not change either at 1 month or at 3 months after surgery (P >.05). Conclusions EX-PRESS shunt, compared to trabeculectomy and Ahmed valve, seems to be a safer procedure regarding the risk of endothelial cell loss. For this reason, it may be the treatment of choice in patients with significant low corneal ECD before surgery or other risk factors for corneal damage
Bulk Heterojunction versus Diffused Bilayer: The Role of Device Geometry in Solution p-Doped Polymer-Based Solar Cells
No full textWe exploit the effect of molecular p-type doping of P3HT in diffused
bilayer (DB) polymer solar cells. In this alternative device geometry, the p-doping is
accomplished in solution by blending the F4-TCNQ with P3HT. The p-doping both
increases the film conductivity and reduces the potential barrier at the interface with
the electrode. This results in an excellent power conversion efficiency of 4.02%,
which is an improvement of ∼48% over the p-doped standard bulk heterojunction
(BHJ) device. Combined VOC−light intensity dependence measurements and Kelvin
probe force microscopy reveal that the DB device configuration is particularly
advantageous, if compared to the conventional BHJ, because it enables optimization
of the donor and acceptor layers independently to minimize the effect of trapping
and to fully exploit the improved transport properties
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