Search results for " Root"
showing 10 items of 627 documents
Aortic valve-sparing root replacement from inside the aorta using three Dacron skirts preserving the native Valsalva sinuses geometry and stabilizing…
2009
We present an alternative idea for valve-sparing technique combining the advantages of the reimplantation and the benefits of the remodeling techniques. We replace the sinuses of Valsalva using three Dacron skirts from inside of the aorta. The physiological anatomy of the Valsalva sinuses and their dynamic properties are preserved and the aortic commissures displacement avoided. The distal rim of each Dacron skirt was anchored to the aorto-ventricular junction using Ticron (2-0) U stitches placed from the ventricular side to the aortic side. We stabilize the base of the aortic annulus to prevent future dilation.
Mid-term results of bicuspid aortic valve repair guided by morphology and function assessment.
2016
Bicuspid aortic valve (BAV) is frequently associated with aortic insufficiency (AI) due to cusp disease and/or aortic root dilatation. Based on functional classification and morphology, a systematic surgical approach was used for aortic valve repair (AVr).From 2004 to 2014, 152 consecutive patients (mean age 55 ± 7 years) with BAV underwent AVr with or without concomitant aortic root surgery. Cusp pathology was treated with central plication in 60 (39.5%) patients, free edge reinforcement in 45 (29.6%), triangular resection in 28 (18.4%) and pericardial patch in 19 (12.5%). Aortic root dilatation was corrected with valve sparing reimplantation in 65 patients. Mean follow-up was 68 ± 36 mont…
The volume of geodesic balls and tubes about totally geodesic submanifolds in compact symmetric spaces
1997
AbstractLet M be a compact Riemannian symmetric space. We give an analytical expression for the area and volume functions of geodesic balls in M and for the area and volume functions of tubes around some totally geodesic submanifolds P of M. We plot the graphs of these functions for some compact irreducible Riemannian symmetric spaces of rank two.
A Kato's second type representation theorem for solvable sesquilinear forms
2017
Kato's second representation theorem is generalized to solvable sesquilinear forms. These forms need not be non-negative nor symmetric. The representation considered holds for a subclass of solvable forms (called hyper-solvable), precisely for those whose domain is exactly the domain of the square root of the modulus of the associated operator. This condition always holds for closed semibounded forms, and it is also considered by several authors for symmetric sign-indefinite forms. As a consequence, a one-to-one correspondence between hyper-solvable forms and operators, which generalizes those already known, is established.
Inverse square root level-crossing quantum two-state model
2020
We introduce a new unconditionally solvable level-crossing two-state model given by a constant-amplitude optical field configuration for which the detuning is an inverse-square-root function of time. This is a member of one of the five families of bi-confluent Heun models. We prove that this is the only non-classical exactly solvable field configuration among the bi-confluent Heun classes, solvable in terms of finite sums of the Hermite functions. The general solution of the two-state problem for this model is written in terms of four Hermite functions of a shifted and scaled argument (each of the two fundamental solutions presents an irreducible combination of two Hermite functions). We pr…
Energy dependence of the differences between the quark and gluon jet fragmentation
1996
Three jet events arising from decays of the Z beson, collected by the DELPHI detector, were used to measure differences in quark and gluon fragmentation. Gluon jets were anti-tagged by identifying b quark jets. Unbiased quark jets came from events with two jets plus one photon. Quark and gluon jet properties in different energy ranges were compared for the first time within the same detector. Quark and gluon jets of nearly the same energy in symmetric three jet event topologies were also compared. Using three independent methods, the average value of the ratio of the mean charged multiplicities of gluon and quark jets is [ r ] = 1.241 +/- 0.015 (stat.) +/- 0.025 (syst.). Gluon jets are broa…
Search for composite and exotic fermions at LEP 2
1999
A search for unstable heavy fermions with the DELPHI detector at LEP is reported. Sequential and non-canonical leptons, as well as excited leptons and quarks, are considered. The data analysed correspond to an integrated luminosity of about 48~pb$^{-1}$ at an $e^+e^-$ centre-of-mass energy of 183~GeV and about 20~pb$^{-1}$ equally shared between the centre-of-mass energies of 172~GeV and 161~GeV. The search for pair-produced new leptons establishes 95\% confidence level mass limits in the region between 70~GeV/$c^2$ and 90~GeV/$c^2$, depending on the channel. The search for singly produced excited leptons and quarks establishes upper limits on the ratio of the coupling of the excited fermio…
Tevatron Combination of Single-Top-Quark Cross Sections and Determination of the Magnitude of the Cabibbo-Kobayashi-Maskawa Matrix Element Vtb
2015
et al.
Come together
2015
Il volume contiene ricerche condotte nell’ambito del PRIN 2011 “Re- cycle Italy. Nuovi cicli di vita per architetture e infrastrutture della città e del paesaggio” e del progetto di Ateneo finanziato dal FFR 2012 dell’Università degli Studi di Palermo. This volume contains a research conducted within the PRIN 2011 "Re-cycle Italy. New life cycles for architecture and infrastructure of the city and the landscape" and of the Palermo University project funded by the FFR 2012 of the University .
Solving ultrasonic ray tracing in parts with multiple material layers through Root-Finding methods
2022
Ultrasonic testing has been used for material analysis and inspection since 1930's. Nevertheless, the applicability of ultrasonic waves to new complex cases is still growing, thanks to the availability of powerful electronics and software. However, the complication that slows down the deployment of ultrasonic inspection to geometric complex parts and structures arises from the wave refraction phenomenon. A clear understanding of the ultrasound wave propagation, impacted by refractions, is crucial to interpret the data obtained from the inspection of multi-layered/multi-medium test subjects as it is not always possible to assume that mechanical waves travel in straight lines. This work prese…