555 resultados para Z(4)-linearity


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Mode of access: Internet.

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Purpose: To evaluate eyelid temperature change and short-term effects on tear film stability and lipid layer thickness in healthy patients using a commercially available warm compress (MGDRx EyeBag) for ophthalmic use. Methods: Eyelid temperature, noninvasive tear film breakup time (NITBUT), and tear film lipid layer thickness (TFLLT) of 22 healthy subjects were measured at baseline, immediately after, and 10 minutes after application of a heated eyebag for 5 minutes to one eye selected at random. A nonheated eyebag was applied to the contralateral eye as a control. Results: Eyelid temperatures, NITBUT, and TFLLT increased significantly from baseline in test eyes immediately after removal of the heated eyebag compared with those in control eyes (maximum temperature change, 2.3 +/- 1.2[degrees]C vs. 0.3 +/- 0.5[degrees]C, F = 20.533, p < 0.001; NITBUT change, 4.0 +/- 2.3 seconds vs. 0.4 +/- 1.7 seconds, p < 0.001; TFLLT change, 2.0 +/- 0.9 grades vs. 0.1 +/- 0.4 grades, Z = -4.035, p < 0.001). After 10 minutes, measurements remained significantly higher than those in controls (maximum temperature change, 1.0 +/- 0.7[degrees]C vs. 0.1 +/- 0.3[degrees]C, F = 14.247, p < 0.001; NITBUT change, 3.6 +/- 2.1 seconds vs. 0.1 +/- 1.9 seconds, p < 0.001; TFLLT change, 1.5 +/- 0.9 vs. 0.2 +/- 0.5 grades, Z = -3.835, p < 0.001). No adverse events occurred during the study. Conclusions: The MGDRx EyeBag is a simple device for heating the eyelids, resulting in increased NITBUT and TFLLT in subjects without meibomian gland dysfunction that seem to be clinically significant. Future studies are required to determine clinical efficacy and evaluate safety after long-term therapy in meibomian gland dysfunction patients. © 2013 American Academy of Optometry

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PURPOSE: To evaluate eyelid temperature change and short-term effects on tear film stability and lipid layer thickness in healthy patients using a commercially available warm compress (MGDRx EyeBag) for ophthalmic use. METHODS: Eyelid temperature, noninvasive tear film breakup time (NITBUT), and tear film lipid layer thickness (TFLLT) of 22 healthy subjects were measured at baseline, immediately after, and 10 minutes after application of a heated eyebag for 5 minutes to one eye selected at random. A nonheated eyebag was applied to the contralateral eye as a control. RESULTS: Eyelid temperatures, NITBUT, and TFLLT increased significantly from baseline in test eyes immediately after removal of the heated eyebag compared with those in control eyes (maximum temperature change, 2.3 ± 1.2 °C vs. 0.3 ± 0.5 °C, F = 20.533, p <0.001; NITBUT change, 4.0 ± 2.3 seconds vs. 0.4 ± 1.7 seconds, p <0.001; TFLLT change, 2.0 ± 0.9 grades vs. 0.1 ± 0.4 grades, Z = -4.035, p <0.001). After 10 minutes, measurements remained significantly higher than those in controls (maximum temperature change, 1.0 ± 0.7 °C vs. 0.1 ± 0.3 °C, F = 14.247, p <0.001; NITBUT change, 3.6 ± 2.1 seconds vs. 0.1 ± 1.9 seconds, p <0.001; TFLLT change, 1.5 ± 0.9 vs. 0.2 ± 0.5 grades, Z = -3.835, p <0.001). No adverse events occurred during the study. CONCLUSIONS: The MGDRx EyeBag is a simple device for heating the eyelids, resulting in increased NITBUT and TFLLT in subjects without meibomian gland dysfunction that seem to be clinically significant. Future studies are required to determine clinical efficacy and evaluate safety after long-term therapy in meibomian gland dysfunction patients. Copyright © 2014 American Academy of Optometry.

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Purpose: To explore the repeatability of lower-order and higher-order ocular aberrations measured in patients with keratoconus. Methods: The IRX-3 (Imagine Eyes, Paris, France) aberrometer was used to record lower-order and higher-order aberrations in 31 eyes of 31 patients with keratoconus. Four monocular measurements were taken consecutively for each patient. The aberrometry data were analysed up to the 5th Zernike order for a 4-mm pupil diameter. The data were evaluated using repeated-measures anova and Friedman analyses. Repeatability was analysed using within-subject standard deviation (SW) and the repeatability limit (r) calculated as 1.96 ×√2×Sw. Results: Of the 11 aberration terms evaluated, the repeatability of Z (2,0) (mean= 1.36μm; SW=0.09μm; r=0.26μm); Z (2,±2) RMS (mean=1.05μm; SW= 0.09μm; r=0.24μm) and Z (4,0) aberrations (mean=0.34μm; SW=0.09 μm; r=0.24μm) showed the highest variability. In contrast, Z (3,±1) RMS aberrations (mean=0.85μm; SW=0.06μm; r=0.16μm) and Z (4,±2) RMS aberrations (mean=0.40μm; SW=0.07μm; r=0.18μm) showed comparatively better repeatability. Conclusions: The lower-order and higher-order aberrations measured in this group of keratoconic patients showed higher levels of variability compared to previous investigations of visually-normal subjects. These results may be of interest to eyecare practitioners involved in the design and fitting of aberration-controlling contact lenses for patients with keratoconus. © 2011 The College of Optometrists.

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The reaction of Cs4[Re6Te8(CN)6]·2H2O with Cu(en)2Cl2 in water affords crystals of a cluster complex [{Cu(H2O)(en) 2}{Cu(en)2}Re6Te8(CN)6]·3H2O. The structure of the compound is determined by single crystal X-ray diffraction (a = 10.8082(4) Å, b = 16.5404(6) Å, c = 24.6480(7) Å, β = 92.696(1)°, V = 4401.5(3) Å3, Z = 4, space group P21/n, R 1 = 0.0331, wR 2 (all data) = 0.0652). In the complex, cluster [Re6Te8(CN)6]4- anions are linked by Cu2+ cations into zigzag chains through cyanide bridges. The coordination environment of the copper cations is complemented by ethylenediamine molecules. Each of the cluster anions is additionally coordinated by a terminal fragment {Cu(H2O)(en)2}. © 2014 Pleiades Publishing, Ltd.

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Thesis (Ph.D.)--University of Washington, 2016-08

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Tese de doutoramento em Farmácia (Toxicologia), apresentada à Faculdade de Farmácia da Universidade de Lisboa, 2009.

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Chains of interacting non-Abelian anyons with local interactions invariant under the action of the Drinfeld double of the dihedral group D-3 are constructed. Formulated as a spin chain the Hamiltonians are generated from commuting transfer matrices of an integrable vertex model for periodic and braided as well as open boundaries. A different anyonic model with the same local Hamiltonian is obtained within the fusion path formulation. This model is shown to be related to an integrable fusion interaction round the face model. Bulk and surface properties of the anyon chain are computed from the Bethe equations for the spin chain. The low-energy effective theories and operator content of the models (in both the spin chain and fusion path formulation) are identified from analytical and numerical studies of the finite-size spectra. For all boundary conditions considered the continuum theory is found to be a product of two conformal field theories. Depending on the coupling constants the factors can be a Z(4) parafermion or a M-(5,M-6) minimal model.

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Este trabalho apresenta a síntese e caracterização de cinco ligantes e quatro complexos derivados de oximas e tiossemicarbazonas. Entre essas, discutem-se as estruturas cristalinas/moleculares determinadas por difração de raios-X em monocristais: do ligante 4-feniltiossemicarbazida-isatina (Ligante 5), do complexo piridina-salicilaldeído-4- feniltiossemicarbazona de niquel (II) (Complexo 1), e do bis-4-feniltiossemicarbazonaisatina de chumbo(II) (Complexo 2). A estrutura do Ligante 5 cristaliza no sistema monoclínico, grupo espacial P21/c, com parâmetros de cela a = 6,3227(2) Å, b = 15,7973(7) Å, c = 14,4572(6) Å, β = 93,9330(10)°, V = 1440,61(10) Å3 , Z = 4. O refinamento da estrutura convergiu aos índices de discordância finais R1 = 0,0520, wR2 = 0,1471. Observa-se ainda a ocorrência de interações intermoleculares do tipo ligações de hidrogênio clássicas [N18−H3---O1′ 2,907(2)Å], com a formação de estruturas dímeras inter-relacionadas por simetria dentro da cela cristalina. Para a estrutura cristalina do Complexo 1, observa-se NC=4, e geometria de coordenação quadrada plana, onde o ligante saliciladeído-4-feniltiossemicarbazida comporta-se como quelante tridentado, e completando a esfera de coordenação do centro metálico temos uma molécula de piridina. A estrutura cristaliza no sistema monoclínico, grupo espacial P21/m, parâmetros de cela a = 12,8211(2) Å, b = 5,73370(10) Å, c = 23,9950(4) Å, β = 101,0910(10)°, V = 1730,98(5) Å3 , índices de discordância finais R1= 0,0320, wR2 = 0,0888, Z=3. O Complexo 1 apresenta ainda interações intermoleculares do tipo [N(3)-H(3)---S(1) = 3,5838(17)º, N(3)–H(3A)---S(1) = 160,91(19)º], formando estruturas dímeras e ligação de hidrogênio intramolecular não-clássica do tipo [C(10)-H(10)---N(2) = 2,838(2)º e C(10) – H(10)---N(2) = 122º]. A estrutura cristalina do complexo 2, apresenta duas formas independentes (uma com centro representado por Pb1 e outra por Pb2). Para a unidade com Pb1 temos o complexo composto por duas unidades do Ligante 5, que comportam-se como quelantes tridentados, e a esfera de coordenação é completada por interações intermoleculares do tipo η 2 areno π e através da ligação polarizada com o O1 da moléculas vizinha, o que confere ao íon Pb1 NC=9. A unidade Pb2 apresenta apenas as duas unidades do Ligante 5 coordenadas conferindo-lhe NC=6. A estrutura cristaliza no sistema monoclínico, grupo espacial C2/c, parâmetros de cela a = 37,9747(6) Å, b= 9,51280(10) Å, c = 31,4378(5) Å, β = 125,951(2)°, V= 9193,5(2) Å3 , Z = 4, índices de discordância finais= R1 = 0,0643, wR2 = 0,1227.

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Background: Human immunodeficiency virus (HIV) associated tuberculosis (TB) remains a major global public health challenge, with an estimated 1.4 million patients worldwide. Co-infection with HIV leads to challenges in the diagnosis and treatment of patients. Objectives: The aim of this study was to assess treatment outcomes of a cohort of smear positive TB-HIV co-infected patients over a five-year study period. Methods: A retrospective cohort study of 600 smear-positive tuberculosis patients registered at the chest unit of the University of Nigeria Teaching Hospital, Enugu from January 2008 to December 2012 was done. The data was analyzed using SPSS Version 17. Results: One hundred and three (17.2%) of the patients were co-infected with TB/HIV, while 398 (66.3%) and 99 (16.5%) were HIV negative and unknown respectively. Among the co-infected patients, 45(43.7%) were cured as against 222(55.8%) in the TBHIV negatives (Z=4.53, p=0.000, 95%CI= 0.12-0.34). Respectively in the TB-HIV co-infected and TB-HIV negative patients, treatment completed were 21(20.4%) and 71(17.8%) (Z=9.15, p=0.000, 95%= 0.4035-0.60); defaulted 19(18.5%) vs 70 (17.6%) (Z=9.29, p=0.000, 95%CI=0.42-0.60), died 10(9.7%) vs. 6(1.5%) (Z=1.22, p=0.224, 95%CI= -0.0286-0.1086), and failures were 1(0.9%) vs. 7(1.8%) (Z=2.48, p=0.013, 95%CI=0.04-0.10). Treatment success rate was lower in TB-HIV co-infected patients, 64.1% compared to TB-HIV negative patients with 73.6%. Also those that defaulted among the TB-HIV co-infected patients (18.5%) were higher than 17.6% among TB-HIV negative patients, a difference of 0.9%. Conclusion: Findings demonstrate that HIV co-infection affects TB treatment outcomes adversely. Treatment adherence, timely and sustained access to antiretroviral therapy for TB/HIV co-infected patients are important.

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Gabapentin, a widely used antiepileptic drug, crystallizes in multiple polymorphic forms. A new crystal form of gabapentin monohydrate in the space group Pbca is reported and the packing arrangement compared with that of a previously reported polymorph in the space group P2(1)/c [Ibers, J.A. (2001) Acta Crystallogr; C57:641]. Gabapentin polymorphs can also occur from a selection of one of the two distinct chair forms of the 1,1-disubstituted cyclohexane. Crystal structures of the E and Z isomers of 4-tert-butylgabapentin provide models for analyzing anticipated packing modes in the conformational isomers of gabapentin. The E isomer crystallized in the space group Pca2(1), while the Z isomer crystallized in the space group P2(1)/c. The crystal structure of E-4-tert-butylgabapentin provides the only example of a structure in a non-centrosymmetric space group. Crystal structures of the hydrochloride and hydrobromide salts of 4-tert-butyl derivatives are reported. The results suggest that for gabapentin, a large 'polymorph-space' may be anticipated, in view of the multiple conformational states that are accessible to the molecule.

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比较稀土催聚1,4—聚丁二烯橡胶和几种不同温度下聚合的镍催聚1,4—聚丁二烯橡胶的σy 和[η],从中得知链缠结的变化是影响σy 和[η]以及 τ的主要原因,而微观结构的变化可能是影响链缠结的因素之一,1,4—聚丁二烯橡胶的加工性能与链缠结有关。