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1.
IEEE Trans Image Process ; 25(7): 3167-3181, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27071169

RESUMO

We here establish and exploit the result that 2D isotropic self-similar fields beget quasi-decorrelated wavelet coefficients and that the resulting localised log sample second moment statistic is asymptotically normal. This leads to the development of a semi-local scaling exponent estimation framework with optimally modified weights. Furthermore, recent interest in penalty methods for least square problems and generalized Lasso for scaling exponent estimation inspires the simultaneous incorporation of both bounding box constraints and total variation smoothing into an iteratively reweighted least-square estimator framework. Numerical results on fractional Brownian fields with global and piecewise constant, semi-local Hurst parameters illustrate the benefits of the new estimators.

2.
Nano Lett ; 14(10): 5973-8, 2014 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25233371

RESUMO

The fluorescence of organic fluorophore molecules is enhanced when they are placed in contact with certain metals (Al, Ag, Cu, Au, etc.) whose surface plasmon waves couple into the radiative modes of the molecules and increase the radiative efficiency. Here, we report a hitherto unknown size dependence of this metal-enhanced fluorescence (MEF) effect in the nanoscale. When the molecules are deposited in nanoporous anodic alumina films with exposed aluminum at the bottom of the pores, they form organic nanowires standing on aluminum nanoparticles whose plasmon waves have much larger amplitudes. This increases the MEF strongly, resulting in several orders of magnitude increase in the fluorescence intensity of the organic fluorophores. The increase in intensity shows an inverse superlinear dependence on nanowire diameter because the nanowires also act as plasmonic "waveguides" that concentrate the plasmons and increase the coupling of the plasmons with the radiative modes of the molecules. Furthermore, if the nanoporous template housing the nanowires has built-in electric fields due to space charges, a strong molecule-specific red- or blue-shift is induced in the fluorescence peak owing to a renormalization of the dipole moment of the molecule. This can be exploited to detect minute amounts of target molecules in a mixture using their optical signature (fluorescence) despite the presence of confounding background signals. It can result in a unique new technology for biosensing and chemical sensing.


Assuntos
Óxido de Alumínio/química , Corantes Fluorescentes/química , Metais/química , Nanoestruturas/química , Alumínio/química , Fluorescência , Nanoestruturas/ultraestrutura , Porosidade , Ressonância de Plasmônio de Superfície/métodos
3.
Arch Soc Esp Oftalmol ; 79(12): 587-8; 589-90, 2004 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-15627924
4.
Adv Ther ; 17(2): 84-93, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11010059

RESUMO

This review examines the impact of moderate to severe dry eye disease on daily life and medical-resource utilization. The results suggest that current treatment paradigms can lead to unacceptable costs in both quality of life and progressive use of healthcare resources. Evidence linking this disease to T-cell-mediated inflammatory processes lays the foundation for understanding the clinical benefits of topical cyclosporine, an immunomodulatory and anti-inflammatory agent.


Assuntos
Síndromes do Olho Seco , Adulto , Idoso , Efeitos Psicossociais da Doença , Síndromes do Olho Seco/economia , Síndromes do Olho Seco/epidemiologia , Síndromes do Olho Seco/imunologia , Síndromes do Olho Seco/terapia , Feminino , Humanos , Inflamação/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estados Unidos/epidemiologia
6.
Vet Ther ; 1(4): 273-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-19757575

RESUMO

The efficacy of a 65% permethrin topically applied spot-on formulation (Defend EXspot Topical Remedy for Dogs, Schering-Plough Animal Health, Union, NJ) was determined against the dog mite, Cheyletiella yasguri (Smiley, 1965). Female dogs and their litters comprised the experimental unit, and all dogs in an experimental unit were treated on the same day 4 to 6 weeks after whelping. Mites and mite eggs were counted weekly on an untreated control group of six litters (15 pups) and on a group of six litters (14 pups) treated with 65% permethrin. Pups in the untreated control group maintained high numbers of Cheyletiella yasguri throughout the 14- to 21-day observation period. No mites or mite eggs were detected on dogs within 7 to 21 days after application of 65% permethrin. No adverse reactions were noted during the study. Clinical signs of infestation with C. yasguri--which included skin irritation, thickening of the stratum corneum, scratching with resultant scabs, pruritus, and flaky, scaly skin-were eliminated when mites were killed by the 65% permethrin formulation.


Assuntos
Doenças do Cão/tratamento farmacológico , Inseticidas/uso terapêutico , Infestações por Ácaros/veterinária , Ácaros , Permetrina/uso terapêutico , Animais , Cães , Feminino , Infestações por Ácaros/tratamento farmacológico
7.
Br J Ophthalmol ; 83(4): 384-5, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10434854
8.
Invest Ophthalmol Vis Sci ; 40(6): 1081-90, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10235541

RESUMO

PURPOSE: Differential display analysis was used to look for gender differences in lacrimal gland gene expression. The expression of a female-specific mouse lacrimal gland mRNA that encoded pancreatic lipase-related protein 1 (PLRP1) was identified and characterized. METHODS: Differential display analysis of the exorbital lacrimal glands of male and female Swiss Webster mice detected a potential female-specific cDNA, designated Y2. Using the technique of rapid amplification of cDNA ends, a full-length cDNA of Y2 was obtained and the nucleotide sequence determined. To assess tissue-specific expression, a labeled Y2 cDNA probe was hybridized to RNA blots of male and female mouse lacrimal, harderian, parotid, mandibular, sublingual, and pancreas glands and liver. Y2 cDNA was also hybridized to RNA blots of male and female rat lacrimal gland and male rat pancreas. To determine subcellular localization, Y2 sense and antisense RNA probes were hybridized to female mouse lacrimal gland frozen sections. RESULTS: GenBank database sequence comparisons indicated that Y2 encoded mouse PLRP1. RNA blots documented that PLRP1 was expressed in female, but not in male, mouse lacrimal gland. PLRP1 mRNA was also expressed in male and female mouse sublingual gland and pancreas. Expression of PLRP1 was not detected in male or female rat lacrimal gland. In situ hybridization showed that PLRP1 was expressed in the acinar cells of the female mouse lacrimal gland. CONCLUSIONS: Lacrimal gland expression of PLRP1 mRNA was gender and species specific. Female, but not male, mouse lacrimal gland expressed PLRPI mRNA. Neither female nor male rat lacrimal gland expressed PLRP1 mRNA. PLRP1 protein may be secreted in mouse tears, where it may function as a lipolytic enzyme, modifying tear film lipids.


Assuntos
Aparelho Lacrimal/metabolismo , Lipase/genética , Camundongos/metabolismo , RNA Mensageiro/metabolismo , Caracteres Sexuais , Sequência de Aminoácidos/genética , Animais , Sequência de Bases/genética , DNA Complementar/genética , Feminino , Aparelho Lacrimal/citologia , Masculino , Dados de Sequência Molecular , Polimorfismo Genético/genética , Ratos/metabolismo , Ratos Sprague-Dawley , Glândula Sublingual/metabolismo
12.
Adv Exp Med Biol ; 438: 807-20, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9634971

RESUMO

We developed a Dry Eye Screening Questionnaire for the Dry Eye Epidemiology Projects (DEEP), a proposed large epidemiologic study. All persons who screen positive and a small sample of those who screen negative are to be invited for a diagnostic examination. Containing 19 questions, of which only 14 were used in the analysis, the questionnaire takes only a few minutes to administer on the telephone. To construct a discriminator function and thus a ROC curve, we used stepwise multiple regression on screening responses from a clinic series of 77 cases and 79 controls. Stepwise regression may incorporate into the predictor equation variables whose relation to the predicted is only accidental. Further, misclassification rates are underestimated by the resubstitution method, in which the proportion misclassified is obtained from the same dataset in which the discriminator function was fitted. To counter these problems, we randomly divided the data in half. We chose as predictors only those variables (Dry and Irritated) selected by stepwise regression in both data halves. We estimated unbiased misclassification rates using the unbiased test set method, in which the discriminator is fitted in one data half, and misclassification rates are calculated in the other half. Comparison of ROC curves arising from resubstitution and test set estimates indicates that resubstitution bias in misclassification rate estimation is negligible in our data. A resubstitution estimate made on the entire data is thus preferred. The resulting sensitivity/specificity values are reasonably high (e.g., 60%/94%), suggesting that the questionnaire will be a useful screening tool in the DEEP study. A second discriminator using the sum of all 14 responses is similar in its misclassification characteristics to the first discriminator. A second potentially significant error, arising from applying results from a clinical series to a general population, will be investigated as survey results in DEEP become available.


Assuntos
Síndromes do Olho Seco/epidemiologia , Ceratoconjuntivite Seca/epidemiologia , Inquéritos e Questionários , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Síndromes do Olho Seco/etiologia , Feminino , Humanos , Entrevistas como Assunto , Ceratoconjuntivite Seca/etiologia , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Análise de Regressão , Sensibilidade e Especificidade , Fatores Sexuais , Síndrome de Sjogren/epidemiologia , Telefone , Estados Unidos
18.
J Am Coll Nutr ; 15(5): 439-49, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8892169

RESUMO

OBJECTIVE: A study of children (2-8 years; n = 613) in Belize, Central America, was conducted to determine what proportion of the children might be at risk of vitamin A (vit A) deficiency. The data provide an opportunity to compare results of three methods of assessing vit A status in a population which was not severely malnourished. Serum retinyl ester concentrations were also determined; their relevance to one of the tests, the relative dose response (RDR) test, is discussed. METHODS: The three methods of assessing vit A status were: RDR test, fasting serum retinol concentration, and conjunctival impression cytology (CIC). Retinol-binding protein (RBP), serum retinyl esters and serum zinc concentrations were also determined. RESULTS: Inadequate vit A status was indicated for 17% of subjects by the RDR test (14% cutoff), for 24% by fasting serum retinol concentration (< 0.87 mumol/L), and for 49% by "abnormal" CIC score. Retinyl esters constituted 24% of serum retinoids at the time (5 hours after a retinyl palmitate dose) at which the second blood sample is taken for the RDR test. Regression tree analyses (CART) indicated ethnicity was a predictor of RDR score; ethnicity, stunting and age were predictors of fasting serum retinol concentration; ethnicity and stunting were predictors of 0-hour retinyl ester concentration. CONCLUSION: The three indices of vit A status did not identify the same individuals nor indicate the same percentage of the population to be at risk for vit A deficiency. Increased concentrations of retinyl esters at 5 hours compared to those at 0 hours suggest that insufficient retinol may have been taken up by the liver at 5 hours to release all accumulated retinol-binding protein (RBP) in deficient individuals; prevalence of vit A deficiency might therefore be underestimated by the RDR test. The selection of ethnicity as a predictor of RDR score and of 0-hour retinol and retinyl ester concentrations suggests that factors other than vit A status affect vit A metabolism and may affect the RDR test.


Assuntos
Estado Nutricional , Vitamina A/sangue , Belize , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Etnicidade , Feminino , Humanos , Masculino , Fatores de Risco , Zinco/sangue
19.
J Am Coll Nutr ; 15(5): 439-49, Oct. 1996.
Artigo em Inglês | MedCarib | ID: med-2095

RESUMO

A study of children (2 - 8 years; n = 613) in Belize, Central America, was conducted to determine what proportion of the children might be at risk of vitamin A (vit A) deficiency. The data provide an opportunity to compare results of three methods of assessing vit A status in a population which was not severely malnourished. Serum retinyl ester concentrations were also determined; their relevance to one of the tests, the relative dose response (RDR) test, is discussed. METHODS: The three methods of assessing vit A status were: RDR test, fasting serum rintol concentration, and conjunctival impression cytology (CIC). Retinol-binding protein (RBP), serum retinyl esters and serum zinc concentrations were also determined. RESULTS: Inadequate vit A status was indicated for 17 percent of subjects by the RDR test (14 percent cutoff), for 24 percent by fasting serum retinol concentration (< 0.87 mumol/L), and for 49 prcent by abnormal. CIC score. Retinyl esters constituted 24 percent of serum retinoids at the time (5 hours after a retinyl palmitate dose) at which the second blood sample is taken for the RDR test. Regresssion trees analyses (CART) indicated ethnicity was a predictor of RDR score; ethnicity, stunting and age were predictors of fasting serum retinol concentration; ethnicity and stunting were predictors of O-hour retinyl ester concentration. CONCLUSION: The three indices of vit A status did not identify the same individuals nor indicate the same percentage of the population to be at risk for hours compared to those at O hours suggest that insufficient retinol may have been taken up by the liver at 5 hours to release all accumulated retinol-binding protein (RBP) in deficient individuals; prevalence of vit A deficiency might therefore be underestimated by the RDR test. The selection of ethnicity as a predictor of RDR score and of O-hour retinol and retinyl ester concentrations suggests that factors other than vit A status affect vit A metabolism and may affect the RDR test.(AU)


Assuntos
Estudo Comparativo , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estado Nutricional , Vitamina A/sangue , Belize , Cromatografia Líquida de Alta Pressão , Etnicidade , Fatores de Risco , Zinco/sangue
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