211 research outputs found
Synthesis of novel azo compounds containing 5(4H)-oxazolone ring as potent tyrosinase inhibitors
Six new azo dyes containing of 5(4H)-oxazolone ring were prepared by diazotization of 4-aminohippuric acid and coupling with N,N-dimethylaniline, 1-naphthol and 2-naphthol and condensation with 4-fluoro benzaldehyde or 4-trifluoromethoxy benzaldehyde. The new compounds were fully characterized by spectroscopic techniques. All synthesized compounds exhibited high tyrosinase inhibitory behavior. The results of mushroom tyrosinase inhibition assays indicate that the 4-trifluoromethoxy derivatives have high degrees of inhibition and N,N-dimethylaniline derivatives are better for tyrosinase inhibition than 1-naphthol and 2-naphthol derivatives. All synthesized azo compounds (4a-4f) showed the most potent mushroom tyrosinase inhibition, comparable to that of Kojic acid and l-mimosine, as reference standard inhibitors. © 2013 Elsevier Ltd. All rights reserved
Commensurate period Charge Density Modulations throughout the Pseudogap Regime
Theories based upon strong real space (r-space) electron electron
interactions have long predicted that unidirectional charge density modulations
(CDM) with four unit cell (4) periodicity should occur in the hole doped
cuprate Mott insulator (MI). Experimentally, however, increasing the hole
density p is reported to cause the conventionally defined wavevector of
the CDM to evolve continuously as if driven primarily by momentum space
(k-space) effects. Here we introduce phase resolved electronic structure
visualization for determination of the cuprate CDM wavevector. Remarkably, this
new technique reveals a virtually doping independent locking of the local CDM
wavevector at throughout the underdoped phase diagram of the
canonical cuprate . These observations have significant
fundamental consequences because they are orthogonal to a k-space (Fermi
surface) based picture of the cuprate CDM but are consistent with strong
coupling r-space based theories. Our findings imply that it is the latter that
provide the intrinsic organizational principle for the cuprate CDM state
CenoDerm vs. fascia lata for the prevention of dorsal nasal irregularities in rhinoplasty
Introduction: Dorsal nasal irregularity is a complication of rhinoplasty surgery, mostly seen in patients with thin skin. Acellular dermis (CenoDerm) and homologous fascia lata covering the nasal bone cartilage structure have been used to achieve a smooth surface. In this study, we aimed to investigate clinical outcomes using these two materials. Materials and Methods: After a standard rhinoplasty procedure, a layer of the acellular dermis or homologous fascia lata was placed in the pocket of the dorsum. Patients were evaluated for clinical outcomes at 3, 6, and 12 months after the procedure. Results Forty-two of 68 patients completed the follow-up period. Patient satisfaction was higher in the homologous fascia lata group. Similarly, nasal dorsum inspection and palpation results were better in the homologous fascia lata group compared with the CenoDerm group but was significant in palpation (P=0.00). There was no complete absorption in the homologous fascia lata group 6 months after surgery (P= 0.04 vs. CenoDerm) but no significant difference was observed at 12 months. Conclusion: Homologous fascia lata is better than acellular dermis in preventing dorsal nasal irregularity after rhinoplasty in thin-skinned patients
CenoDerm vs. fascia lata for the prevention of dorsal nasal irregularities in rhinoplasty
Introduction: Dorsal nasal irregularity is a complication of rhinoplasty surgery, mostly seen in patients with thin skin. Acellular dermis (CenoDerm) and homologous fascia lata covering the nasal bone cartilage structure have been used to achieve a smooth surface. In this study, we aimed to investigate clinical outcomes using these two materials. Materials and Methods: After a standard rhinoplasty procedure, a layer of the acellular dermis or homologous fascia lata was placed in the pocket of the dorsum. Patients were evaluated for clinical outcomes at 3, 6, and 12 months after the procedure. Results Forty-two of 68 patients completed the follow-up period. Patient satisfaction was higher in the homologous fascia lata group. Similarly, nasal dorsum inspection and palpation results were better in the homologous fascia lata group compared with the CenoDerm group but was significant in palpation (P=0.00). There was no complete absorption in the homologous fascia lata group 6 months after surgery (P= 0.04 vs. CenoDerm) but no significant difference was observed at 12 months. Conclusion: Homologous fascia lata is better than acellular dermis in preventing dorsal nasal irregularity after rhinoplasty in thin-skinned patients
Infra-Red Stable Supersymmetry in Chern-Simons Theories with Matter and Quenched Disorder
We study Abelian Chern-Simons field theories with matter fields and global
SU(N) symmetry in the presence of random weak quenched disorder. In the absence
of disorder these theories possess N=2 supersymmetric fixed points and N=1
supersymmetric fixed lines in the infra-red limit. We show that although the
presence of disorder forbids any supersymmetry of the bare action, infra-red
stable supersymmetric fixed points and fixed lines are realized in the
disorder-averaged effective theories.Comment: 8 pp., LaTeX. Explanatory remarks and references added. Version to
appear in Phys. Rev. Let
Gauged Yukawa Matrix Models and 2-Dimensional Lattice Theories
We argue that chiral symmetry breaking in three dimensional QCD can be
identified with N\'eel order in 2-dimensional quantum antiferromagnets. When
operators which drive the chiral transition are added to these theories, we
postulate that the resulting quantum critical behavior is in the universality
class of gauged Yukawa matrix models. As a consequence, the chiral transition
is typically of first order, although for a limited class of parameters it can
be second order with computable critical exponents.Comment: LaTeX, 11 page
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