172,342 research outputs found
Secondary Tuck Revisited
No full textIntroduction: The best result from a facelift cannot last forever. We cannot stop the clock on the aging process, but with a planned surgical maintenance program the effects of aging can be retarded. Materials and Methods: This article will describe the technique of a secondary tuck as well as provide the results of a quality evaluation study of our patients who have undergone a secondary tuck. Results: The study revealed that more than 90% of those who had responded were satisfied with the secondary tuck and would undergo the surgery again. Respondents also stated that recovery time for the surgery was less than 1 week, and that they experienced little to no complications. Discussion: A traditional facelift combined with a secondary tuck, performed under local anesthesia preferably 12–24 months after the original facelift, is a viable option for those seeking to maintain the youthful appearance obtained from the original facelift. The secondary tuck can be performed periodically thereafter when the patient desires further maintenance. </jats:sec
Reactivity of Tuck-in and Tuck-over Uranium Metallocene Complexes
No full textThe reactivity of the uranium tuck-in and tuck-over cyclopentadienyl moieties {[η5:η1-C5Me4CH2]U}2+ and {U[μ-η5:η1-C5Me4CH2]U}6+, respectively, has been investigated by examining the reactivity of (C5Me5)U[μ-η5:η1:η1-C5Me3(CH2)2](μ-H)2U(C5Me5)2, 1, and (C5Me5)(η5:η1-C5Me4CH2)(hpp)U [(hpp)− = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinato], 2, with hydrogen, silyl halide, sulfide, amine, and hydrocarbon reagents. The reactivity of 2, which has a single tuck-in reactive site, provides valuable comparisons with that of 1, where the presence of two hydride ligands as well as both tuck-in and tuck-over moieties leads to products in which multiple transformations have occurred. Both 1 and 2 react with H2 to form hydrides, namely, the [(C5Me5)2UH2]2/[(C5Me5)2UH]2 equilibrium mixture and (C5Me5)2(hpp)UH, 3, respectively. Attempts to make a simple chloride derivative of 1 with Me3SiCl yielded a new tethered metallocene, (C5Me5)ClU(η5-C5Me4CH2SiMe2CH2-κC), 4, which formally results from a silylmethyl C−H bond activation as well as insertion of the silyl group into the U−CH2 tuck-in linkage. The trivalent chloride [(C5Me5)2UCl]3, 5, is the byproduct of this reaction. This sequence of reactions is probably not initiated by the tuck-in functionality, since 2 does not react with Me3SiCl under comparable conditions. Hydride complex 3 reacts readily with Me3SiCl to form (C5Me5)2(hpp)UCl, but (C5Me5)2(hpp)UMe, 6, requires 100 °C to form the chloride. Complex 1 also displays complicated reactivity with HCCPh, whereas 2 and 3 react with this substrate to form (C5Me5)2(hpp)U(CCPh), 7, in high yield. Complex 1 converts PhSSPh cleanly to (C5Me5)2U(SPh)2, 8, in a reaction that involves S−S cleavage and C−H bond formation. Complex 1 reacts with a 1:1 mixture of PhSSPh and p-tolylSS-p-tolyl to form a 1:2:1 mixture of (C5Me5)2U(SPh)2, 8, (C5Me5)2U(SPh)(S-p-tolyl), 9, and (C5Me5)2U(S-p-tolyl)2, 10, but the mechanistic implications are compromised by exchange of 8 with 10 to make 9. PhSH, a possible intermediate in a σ-bond metathesis reaction pathway for the 1/PhSSPh reaction, reacts with 1 to form 8. Complex 2 forms a σ-bond metathesis product, (C5Me4CH2SPh)(C5Me5)(hpp)U(SPh), 11, from PhSSPh that contains a new peralkylated cyclopentadienyl ligand. The reaction of 2 and PhSH forms (C5Me5)2(hpp)U(SPh), 12. Complexes 1 and 2 react similarly with PhNH2 to generate amide products (C5Me5)2U(NHPh)2, 13, and (C5Me5)2(hpp)U(NHPh), 14, respectively. No reactions were observed between complex 1 or 2 and methane, benzene, or toluene, but 1 and 2 react with CuI to form (C5Me5)2UI2, 15, and (C5Me5)2(hpp)UI, 16, respectively, in which the CH2 tuck components have been converted to methyl groups
Mirboo North Rifle Club
No full textThe Mirboo North Rifle Club, about 1907. The members are seated holding their rifles, while a row of women stand behind. The members in the photograph are Geo. Sutton, P. Burchell, Jas Abbott, G. McKenzie, Frank Dawson, Tony Watkins, Geo. St Ellen, C. McCormack, Jas Marshall, Tom Clark, T. Ashworth Senior, W. Pickering, W.J. McCormack, Norman Gill, R. Alford, Fred Bliss, Chas Bliss, W. Tuck, Mat Gargan, Tom Gould, Jack Clark, Jim Giles, W. Stanton, Tom Ashworth Junior and C. Downing
Reactivity of Tuck-in and Tuck-over Uranium Metallocene Complexes
No full textThe reactivity of the uranium tuck-in and tuck-over cyclopentadienyl moieties {[η5:η1-C5Me4CH2]U}2+ and {U[μ-η5:η1-C5Me4CH2]U}6+, respectively, has been investigated by examining the reactivity of (C5Me5)U[μ-η5:η1:η1-C5Me3(CH2)2](μ-H)2U(C5Me5)2, 1, and (C5Me5)(η5:η1-C5Me4CH2)(hpp)U [(hpp)− = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinato], 2, with hydrogen, silyl halide, sulfide, amine, and hydrocarbon reagents. The reactivity of 2, which has a single tuck-in reactive site, provides valuable comparisons with that of 1, where the presence of two hydride ligands as well as both tuck-in and tuck-over moieties leads to products in which multiple transformations have occurred. Both 1 and 2 react with H2 to form hydrides, namely, the [(C5Me5)2UH2]2/[(C5Me5)2UH]2 equilibrium mixture and (C5Me5)2(hpp)UH, 3, respectively. Attempts to make a simple chloride derivative of 1 with Me3SiCl yielded a new tethered metallocene, (C5Me5)ClU(η5-C5Me4CH2SiMe2CH2-κC), 4, which formally results from a silylmethyl C−H bond activation as well as insertion of the silyl group into the U−CH2 tuck-in linkage. The trivalent chloride [(C5Me5)2UCl]3, 5, is the byproduct of this reaction. This sequence of reactions is probably not initiated by the tuck-in functionality, since 2 does not react with Me3SiCl under comparable conditions. Hydride complex 3 reacts readily with Me3SiCl to form (C5Me5)2(hpp)UCl, but (C5Me5)2(hpp)UMe, 6, requires 100 °C to form the chloride. Complex 1 also displays complicated reactivity with HCCPh, whereas 2 and 3 react with this substrate to form (C5Me5)2(hpp)U(CCPh), 7, in high yield. Complex 1 converts PhSSPh cleanly to (C5Me5)2U(SPh)2, 8, in a reaction that involves S−S cleavage and C−H bond formation. Complex 1 reacts with a 1:1 mixture of PhSSPh and p-tolylSS-p-tolyl to form a 1:2:1 mixture of (C5Me5)2U(SPh)2, 8, (C5Me5)2U(SPh)(S-p-tolyl), 9, and (C5Me5)2U(S-p-tolyl)2, 10, but the mechanistic implications are compromised by exchange of 8 with 10 to make 9. PhSH, a possible intermediate in a σ-bond metathesis reaction pathway for the 1/PhSSPh reaction, reacts with 1 to form 8. Complex 2 forms a σ-bond metathesis product, (C5Me4CH2SPh)(C5Me5)(hpp)U(SPh), 11, from PhSSPh that contains a new peralkylated cyclopentadienyl ligand. The reaction of 2 and PhSH forms (C5Me5)2(hpp)U(SPh), 12. Complexes 1 and 2 react similarly with PhNH2 to generate amide products (C5Me5)2U(NHPh)2, 13, and (C5Me5)2(hpp)U(NHPh), 14, respectively. No reactions were observed between complex 1 or 2 and methane, benzene, or toluene, but 1 and 2 react with CuI to form (C5Me5)2UI2, 15, and (C5Me5)2(hpp)UI, 16, respectively, in which the CH2 tuck components have been converted to methyl groups
Going 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
Tuck, G. S., & Heinzel, H. — A Field Guide to the Seabirds of Britain and the World. Collins, St James’s Place, London
No full textJouanin C. Tuck, G. S., & Heinzel, H. — A Field Guide to the Seabirds of Britain and the World. Collins, St James’s Place, London. In: Revue d'Écologie (La Terre et La Vie), tome 34, n°1, 1980. pp. 155-157
Organolutetium Vinyl and Tuck-Over Complexes via C−H Bond Activation
No full textThe vinyl C−H bond of tetramethylfulvene is activated in the presence of [(C5Me5)2LuH]x, 1, to form a vinyl organolutetium complex, (C5Me5)2Lu(CHC5Me4), 2. Also formed in the reaction is the “tuck-over” complex, (C5Me5)2Lu(μ-H)(μ-η:η5-CH2C5Me4)Lu(C5Me5), 3, containing a (CH2C5Me4)- moiety long postulated to exist in organolutetium chemistry but never crystallographically characterized. Evidence for these C−H bond activations by a “(C5Me5)3Lu” intermediate, 4, is presented. Complex 3 can also be made in high yield by thermolysis of 1. Under H2, 1 catalytically hydrogenates TMF to C5Me5H
Organolutetium Vinyl and Tuck-Over Complexes via C−H Bond Activation
No full textThe vinyl C−H bond of tetramethylfulvene is activated in the presence of [(C5Me5)2LuH]x, 1, to form a vinyl organolutetium complex, (C5Me5)2Lu(CHC5Me4), 2. Also formed in the reaction is the “tuck-over” complex, (C5Me5)2Lu(μ-H)(μ-η:η5-CH2C5Me4)Lu(C5Me5), 3, containing a (CH2C5Me4)- moiety long postulated to exist in organolutetium chemistry but never crystallographically characterized. Evidence for these C−H bond activations by a “(C5Me5)3Lu” intermediate, 4, is presented. Complex 3 can also be made in high yield by thermolysis of 1. Under H2, 1 catalytically hydrogenates TMF to C5Me5H
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
A Comparative study of marketing communications of local and foreign national small grocery tuck-shop owners in selected municipalities in the Free State Province
No full textPublished ThesisDespite evidence of use and research in marketing communications by large retail businesses in South Africa, the continued proliferation of small grocery tuck-shops in South African townships has presented the small retail business environment with stiff competition from local and foreign national-owned businesses. Observations show that foreign national tuck-shop owners employ best customer services and effective packaging of their goods as part of their marketing communications, yet no empirical evidence is available to suggest that local tuck-shop owners do the same. The objective of this study was to investigate the differences in marketing communications between foreign national tuck-shop owners and local tuck-shop owners in the Free State Province, South Africa. Using descriptive, cross-sectional comparative research design, a population of 464 tuck-shop owners, foreign nationals and South Africans provided data for the research. Stratified proportional random sampling technique was used to select a sample size of 236, 136 foreign nationals and 100 South Africans. Data was collected using a self-administered structured questionnaire, with items measured on a Likert scale of (1) Strongly Disagree to (5) Strongly Agree, as well some from (1) Not at all to (5) To a greater extent. Data was analysed using descriptive statistics, Exploratory Factor analysis, Student T-test for independent samples, Chi-square and 4-way ANOVA. The findings of the study revealed that the choice of marketing communications is not the same across nationalities, except for the broadcast media and market research. The results further revealed that foreign national tuck-shop owners are using marketing communications more than their South African counterparts. Implications for the improvement of marketing communications among local tuck-shop owners are discussed.
Key words: marketing communications, small grocery tuck-shops, foreign national tuck-shop owners, local tuck-shop owner
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