The Experts below are selected from a list of 15309 Experts worldwide ranked by ideXlab platform
Nobuyuki Harada - One of the best experts on this subject based on the ideXlab platform.
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ecd cotton effect approximated by the Gaussian Curve and other methods
ChemInform, 2010Co-Authors: Philip J. Stephens, Nobuyuki HaradaAbstract:To determine the absolute configuration of chiral compounds, theoretical calculations of ECD spectra have been extensively carried out, where the shape of component CD Cotton effects was approximated by the Gaussian distribution Curve. However, in some articles, errors are found in the equations of Gaussian Curve expressing CD Cotton effects. In this short review, the correct and general forms of the Gaussian equation and the approximation of the CD Curve by other methods are described.
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ECD cotton effect approximated by the Gaussian Curve and other methods.
Chirality, 2010Co-Authors: Philip J. Stephens, Nobuyuki HaradaAbstract:To determine the absolute configuration of chiral compounds, theoretical calculations of ECD spectra have been extensively carried out, where the shape of component CD Cotton effects was approximated by the Gaussian distribution Curve. However, in some articles, errors are found in the equations of Gaussian Curve expressing CD Cotton effects. In this short review, the correct and general forms of the Gaussian equation and the approximation of the CD Curve by other methods are described. Chirality, 2010. © 2009 Wiley-Liss, Inc.
Philip J. Stephens - One of the best experts on this subject based on the ideXlab platform.
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ecd cotton effect approximated by the Gaussian Curve and other methods
ChemInform, 2010Co-Authors: Philip J. Stephens, Nobuyuki HaradaAbstract:To determine the absolute configuration of chiral compounds, theoretical calculations of ECD spectra have been extensively carried out, where the shape of component CD Cotton effects was approximated by the Gaussian distribution Curve. However, in some articles, errors are found in the equations of Gaussian Curve expressing CD Cotton effects. In this short review, the correct and general forms of the Gaussian equation and the approximation of the CD Curve by other methods are described.
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ECD cotton effect approximated by the Gaussian Curve and other methods.
Chirality, 2010Co-Authors: Philip J. Stephens, Nobuyuki HaradaAbstract:To determine the absolute configuration of chiral compounds, theoretical calculations of ECD spectra have been extensively carried out, where the shape of component CD Cotton effects was approximated by the Gaussian distribution Curve. However, in some articles, errors are found in the equations of Gaussian Curve expressing CD Cotton effects. In this short review, the correct and general forms of the Gaussian equation and the approximation of the CD Curve by other methods are described. Chirality, 2010. © 2009 Wiley-Liss, Inc.
Peter J F M Lohuis - One of the best experts on this subject based on the ideXlab platform.
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benefits of a short practical questionnaire to measure subjective perception of nasal appearance after aesthetic rhinoplasty
Plastic and Reconstructive Surgery, 2013Co-Authors: Peter J F M Lohuis, Arno Knobbe, Wouter Duivesteijn, Sara Hakim, Abeljan TasmanAbstract:BACKGROUND: The authors tested a short, practically designed questionnaire to assess changes in subjective perception of nasal appearance in patients before and after aesthetic rhinoplasty. METHODS: A prospective cohort study was conducted in a group of 121 patients who desired aesthetic rhinoplasty and were operated on by one surgeon. The questionnaire contained five questions (E1-E5) based on a five-point Likert scale and a visual analogue scale (range, 0 to 10). Two questions were designed as trick questions to help the surgeon screen for signs of body dysmorphic disorder. RESULTS: All patients rated the appearance of their nose as improved after surgery. The visual analogue scale revealed a Gaussian Curve of normal distribution (range, 0.5 to 10) around a significant improvement (mean, 4.36 points, p = 0.018). Also, question E1, question E2, and the sum of questions E1 through E5 showed a statistically significant improvement after surgery (p = 1.74 × 10, p = 4.29 × 10, and p = 9.23 × 10, respectively). The authors found a linear relationship between preoperative score on the trick questions and postoperative increase in visual analogue scale score. Test-retest reliability could be investigated in 74 of 121 patients (61 percent) and showed a positive correlation between postoperative (1 year after surgery) and repostoperative response (2 to 4 years after surgery). CONCLUSIONS: The authors concluded that a surgeon performing aesthetic rhinoplasty can benefit from using this questionnaire. It is simple, takes no more than 2 minutes to complete, and provides helpful subjective information regarding patients' preoperative nasal appearance and postoperative surgical outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
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split hump technique for reduction of the overprojected nasal dorsum a statistical analysis on subjective body image in relation to nasal appearance and nasal patency in 97 patients undergoing aesthetic rhinoplasty
Archives of Facial Plastic Surgery, 2012Co-Authors: Peter J F M Lohuis, Sara Farajhakim, Arno Knobbe, Wouter Duivesteijn, Gregor BranAbstract:OBJECTIVES: To describe the split hump technique (SHT) and to examine its effectiveness for correction of an overprojected nasal dorsum in patients undergoing aesthetic rhinoplasty. METHODS: This prospective study included 97 patients. Objective assessment was performed using a short, practical questionnaire. Investigation focused on nasal patency and the patient perception of body image in relation to nasal appearance using 5-point Likert scale questions and visual analog scales. RESULTS: Use of the SHT resulted in a significant improvement in nasal patency and aesthetic nasal perception. Sum functional question scores decreased from 9.154 to 6.351 and aesthetic question scores from 13.897 to 6.825 (P < .001 for both). Mean aesthetic visual analog scale scores improved in all patients, from 3.346 to 7.782 (P < .001). Graphic illustration of this improvement revealed a Gaussian Curve of normal distribution around a mean (SD) improvement of 4.48 (1.93). CONCLUSIONS: Traditional en bloc humpectomy maneuvers are frequently combined with spreader graft use to avoid postoperative inferomedial repositioning of the upper lateral cartilages and inverted-V deformity. The SHT for correction of the overprojected dorsum creates a paradigm change in this patient group. The transverse segments of the upper lateral cartilages are saved and repositioned instead of being resected as a part of an en bloc osseocartilaginous composite hump resection in a transverse plane. Several modifications of the SHT enable the surgeon to deproject the nose while keeping sufficient strength in the keystone area and augmenting dorsal width. Using statistical analysis of subjective patient data, we could prove a broad acceptance and appreciation for the SHT.
Abeljan Tasman - One of the best experts on this subject based on the ideXlab platform.
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benefits of a short practical questionnaire to measure subjective perception of nasal appearance after aesthetic rhinoplasty
Plastic and Reconstructive Surgery, 2013Co-Authors: Peter J F M Lohuis, Arno Knobbe, Wouter Duivesteijn, Sara Hakim, Abeljan TasmanAbstract:BACKGROUND: The authors tested a short, practically designed questionnaire to assess changes in subjective perception of nasal appearance in patients before and after aesthetic rhinoplasty. METHODS: A prospective cohort study was conducted in a group of 121 patients who desired aesthetic rhinoplasty and were operated on by one surgeon. The questionnaire contained five questions (E1-E5) based on a five-point Likert scale and a visual analogue scale (range, 0 to 10). Two questions were designed as trick questions to help the surgeon screen for signs of body dysmorphic disorder. RESULTS: All patients rated the appearance of their nose as improved after surgery. The visual analogue scale revealed a Gaussian Curve of normal distribution (range, 0.5 to 10) around a significant improvement (mean, 4.36 points, p = 0.018). Also, question E1, question E2, and the sum of questions E1 through E5 showed a statistically significant improvement after surgery (p = 1.74 × 10, p = 4.29 × 10, and p = 9.23 × 10, respectively). The authors found a linear relationship between preoperative score on the trick questions and postoperative increase in visual analogue scale score. Test-retest reliability could be investigated in 74 of 121 patients (61 percent) and showed a positive correlation between postoperative (1 year after surgery) and repostoperative response (2 to 4 years after surgery). CONCLUSIONS: The authors concluded that a surgeon performing aesthetic rhinoplasty can benefit from using this questionnaire. It is simple, takes no more than 2 minutes to complete, and provides helpful subjective information regarding patients' preoperative nasal appearance and postoperative surgical outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.
K.v.s.n. Raju - One of the best experts on this subject based on the ideXlab platform.
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synthesis of triazole ring containing pentol chain extender and its effect on the properties of hyperbranched polyurethane urea coatings
Journal of Applied Polymer Science, 2012Co-Authors: K G Priyanka, Aswini K Mishra, Sasidhar Kantheti, Ramanuj Narayan, K.v.s.n. RajuAbstract:This article describes the synthesis and property evaluation of different hyperbranched polyurethane-urea (HBPUU) coatings based on a newly synthesized triazole ring-based pentol chain extender. For this initially, the chain extender was synthesized using acetylene azide click reaction and the structure of the intermediate compounds were confirmed by 1H-, 13C-NMR, FTIR, and ESI-mass spectrometry. In the further steps, the required HBPUU coatings were prepared by a systematic three-step reaction process. In the first step, a isocyanate terminated prepolymer resin was synthesized at NCO/OH ratio of 1.2 : 1, while the second and third step involves the partially chain extension followed by moisture curing. The excess NCO content in the prepolymer was calculated by standard dibutylamine titration method and partially (10, 20, 30, 50, and 70% of the excess NCO content) chain extended with the pentol chain extender and remaining was moisture cured. The structure property relation of different HBPUU coating films were analyzed by FTIR peak deconvulation technique using Gaussian Curve fitting procedure while, their viscoelastic and thermo-mechanical properties were measured by dynamic mechanical thermal analysis, thermo gravimetric analysis, differential scanning calorimetric, and universal testing machine instruments. These results showed that thermal stability, glass transition temperature (Tg), elongation at break increases but the storage and tensile modulus decreases with increasing the percent loading of the triazole chain extender. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
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ft ir and xps studies of polyurethane urea imide coatings
Progress in Organic Coatings, 2006Co-Authors: Aswini K Mishra, D K Chattopadhyay, B Sreedhar, K.v.s.n. RajuAbstract:A series of polyurethane (PU)-urea-imide coatings were synthesized by a systematic three-step reaction process. Initially isocyanate terminated PU prepolymers were prepared by reacting soft segments such as polyester polyols (prepared from neopentyl glycol, adipic acid, isophathalic acid and trimethylol propane) or polyether polyols (polypropylene glycol-1000) with hard segments such as 2,4-toluene diisocyanate or isophorone diisocyanate with NCO/OH ratio of 2:1. Heterocyclic imide ring into the PU backbone was incorporated by co-polymerization with pyromellitic dianhydride (PMDA) from the excess NCO groups in the PU prepolymer with an NCO/anhydride ratio of 1:0.5 and the surplus NCO content after imidization was moisture cured. PU-urea-imide coatings were also obtained by partial chain extension of the excess NCO groups in the NCO terminated PU-imide copolymers, and the remaining excess NCO groups were completely reacted with atmospheric moisture. The obtained polymers were analyzed with Fourier transform-infrared (FT-IR) and angle resolved X-ray photoelectron spectroscopy (AR-XPS). The type and change in intermolecular H-bonding interaction in the PU-urea-imide films with structural variables was identified by deconvolution of the FT-IR spectra using Origin 6.0 software through Gaussian Curve-fitting method. The FT-IR analyses of the PU-urea-imide coating films show dependence of phase separation on the nature of chain extender. Surface characterization data from AR-XPS suggests the dependence of phase segregation behaviour on the nature of the chain extender, which also supports the FT-IR observations.