169,726 research outputs found
Coupled cluster investigation of the electric field gradient induced birefringence of H2, N2, C2H2 and CH4
No full text
Static and frequency-dependent polarizabilities of excited singletstates using coupled cluster response theory
No full textGauge-origin independent magneto optical activity withincoupled-cluster response theory
No full textWe present a gauge-origin independent formulation of the Faraday B term of magnetic circular dichroism and of the Verdet constant of magneto-optical rotation, in terms of first derivatives with respect to the magnetic field strength of gauge invariant coupled cluster response functionals [1]. Gauge invariance is ensured by the derivative formulation in connection with the use of a magnetic field dependent basis of atomic orbitals, the so-called London orbitals. To our knowledge this represent the first application of London atomic orbitals to the calculation of frequency dependent quadratic response properties. The approach can easily be extended to other wavefunction models, and to any other frequency dependent property which can be formulated as total derivative of a (frequency-dependent) functional with respect to the field strengths of a static magnetic perturbation. In other words, any properties for which the frequency dependence is not associated with the magnetic field. This is for example the case for the hypermagnetizabilities in the Cotton-Moutton effect. The implementation of the derived equations is currently undertaken for a CCSD wavefunction on a local version of the Dalton program.
[1] S. Coriani, C. Hättig, P. Jørgensen, T. Helgake
Coupled cluster calculations of the ground state potential andinteraction induced electric properties of the mixed dimers of helium,neon and argon
No full textA Lagrangian, integral-density direct formulation andimplementation of the analytic CCSD and CCSD(T) gradients
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Mitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
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