Search results for "USP"
showing 10 items of 1290 documents
Explicitly correlated internally contracted multireference coupled-cluster singles and doubles theory: ic-MRCCSD(F12∗)
2013
Abstract An explicitly correlated ansatz employing Slater-type geminals and cusp conditions is developed for the internally contracted multireference coupled-cluster singles and doubles method. Only the most important geminal terms are retained in the spirit of earlier work for single-reference theory. Throughout all our test calculations, the new ic-MRCCSD(F12∗) method improves the basis set convergence of many properties, e.g., spectroscopic constants or singlet–triplet splittings, with only little extra computational cost. If a perturbative correction for connected triples is included (the ic-MRCCSD(F12∗)+(T) method), very accurate results can be obtained even with minimal active spaces.
Analysis of eta production using a generalized Lee model
1998
We have investigated the processes N($\pi$, $\pi$)N and N($\pi$, $\eta$)N close to eta threshold using a simple, nonrelativistic Lee model which has the advantage of being analytically solvable. It is then possible to study the Riemann sheets of the S-matrix and the behavior of its resonance poles especially close to threshold. A theoretical simulation of the experimental cusp effect at eta threshold leads to a characteristic distribution of poles on the Riemann sheets. We find a pole located in the $4^{th}$ Riemann sheet that up to now has not been discussed. It belongs to the cusp peak at eta threshold. In addition we obtain the surprising result using the Lee model that the resonance $S_…
Amplitude analysis ofB+→J/ψϕK+decays
2017
The first full amplitude analysis of B+→J/ψϕK+ with J/ψ→μ+μ−, ϕ→K+K− decays is performed with a data sample of 3 fb−1 of pp collision data collected at s√=7 and 8 TeV with the LHCb detector. The data cannot be described by a model that contains only excited kaon states decaying into ϕK+, and four J/ψϕ structures are observed, each with significance over 5 standard deviations. The quantum numbers of these structures are determined with significance of at least 4 standard deviations. The lightest is best described as a D±sD∗∓s cusp, but a resonant interpretation is also possible with mass consistent with, but width much larger than, previous measurements of the claimed X(4140) state. The mode…
Study of η and η′ Photoproduction at MAMI
2017
The reactions γp→ηp and γp→η′p are measured from their thresholds up to the center-of-mass energy W=1.96 GeV with the tagged-photon facilities at the Mainz Microtron, MAMI. Differential cross sections are obtained with unprecedented statistical accuracy, providing fine energy binning and full production-angle coverage. A strong cusp is observed in the total cross section for η photoproduction at the energies in the vicinity of the η′ threshold, W=1896 MeV (Eγ=1447 MeV). Within the framework of a revised ηMAID isobar model, the cusp, in connection with a steep rise of the η′ total cross section from its threshold, can only be explained by a strong coupling of the poorly known N(1895)1/2− …
Generic 3-parameter families of vector fields on the plane, unfolding a singularity with nilpotent linear part. The cusp case of codimension 3
1987
AbstractA cusp type germ of vector fields is a C∞ germ at 0∈ℝ2, whose 2-jet is C∞ conjugate toWe define a submanifold of codimension 5 in the space of germs consisting of germs of cusp type whose 4-jet is C0 equivalent toOur main result can be stated as follows: any local 3-parameter family in (0, 0) ∈ ℝ2 × ℝ3 cutting transversally in (0, 0) is fibre-C0 equivalent to
Influence of cavity type and size of composite restorations on cuspal flexure
2006
Objectives: The present study examines the influence of cavity type, and size of composite restorations on cuspal flexure due to polymerization shrinkage. Methods: Thirty healthy premolars were selected and divided into two experimental groups. Group 1: Mesial, mesiodistal, and MOD cavities were successively prepared in each tooth by means of the SONICSYS approx system (KaVo ®) using a nº 2 (small) diamond tip. Group 2: The same cavity preparation sequence was followed but a nº 3 (medium) tip was used. Cavity preparations were performed and afterwards restored using the same adhesive system and resin composite. Cuspal displacement was measured 15 min after completion of each type of restora…
Effect of cyclic loading on fracture strength and microleakage of a quartz fiber dowel with different adhesive, cement and resin core material combin…
2010
Background: This study evaluated the performance of different adhesive-cement-core combinations coupled with quartz fiber dowels after cyclic loading and fracture strength tests and assessed the microleakage using dye penetration method. Methods: Forty maxillary canines (n=10 per group) were restored with fiber dowels (Quartz fiber DT Light Post) and four adhesive-cement-core material combinations [(Group 1: All-Bond 2+C&B (root) / All-Bond 2+Biscore (core); Group 2: All-Bond 2+Bisfil 2B (root) / All-Bond 2+Bisfil 2B (core); Group 3: Scotchbond 1+RelyX ARC (root) / Scotchbond 1+Supreme (core); Group 4: RelyX Unicem (root) / Scotchbond 1+Filtek Supreme (core)]. The specimens were initially c…
Clinical repercussions and epidemiological considerations of supernumerary canines : a 26 case series
2019
Background To establish the prevalence of supernumerary canines (SNC) in a sector of the population of Madrid (Spain), as well possible complications associated with this unusual developmental variation. Material and Methods This observational study was performed between 2005 and 2017, among 21,615 patients seeking dental treatment at the Faculty of Dentistry, Complutense University of Madrid (Spain), and at the Virgen de la Paloma Hospital, Madrid (Spain); 22 patients with 26 SNCs were diagnosed. These 22 patients underwent clinical and radiological exploration, registering patient data. Results SNCs presented a prevalence of 0.10% of the study population. The supernumerary teeth (SNT) wer…
Laterizi maiolicati nella costruzione delle cuspidi in area siciliana
2008
Segni vistosi di una monumentalità povera, le cuspidi maiolicate siciliane sono espressione di antichi saperi costruttivi in grado di coniugare un’originale concezione statica con la tradizione decorativa dai forti toni coloristici. L’indagine ravvicinata ne approfondisce la varietà delle conformazioni e degli originali elementi laterizi di cui si compongono, i sistemi costruttivi ed il repertorio ornamentale, l’intrinseca fragilità che le espone a dissesti ed a restauri non sempre corretti.