5,529 research outputs found
Recommended from our members
Scalar nanosecond pulse generation in a nanotube mode-locked environmentally stable fiber laser
We report an environmentally stable nanotube mode-locked fibre laser
producing linearly-polarized, nanosecond pulses. A simple
all-polarization-maintaining fibre ring cavity is used, including 300 m of
highly nonlinear fibre to elongate the cavity and increase intracavity
dispersion and nonlinearity. The laser generates scalar pulses with a duration
of 1.23 ns at a centre wavelength of 1042 nm, with 1.3-nm bandwidth and at
641-kHz repetition rate. Despite the long cavity, the output characteristics
show no significant variation when the cavity is perturbed, and the degree of
polarization remains at 97%
Ácidos orgânicos de caldo de três variedades de cana-de-açúcar (Saccharum spp) em quatro estádios de maturidade
Levels of trans-aconitic, malic, malonic and succinic acids were measured in sugarcane juice from three varieties in four maturity stages. Trans-aconitic acid represented about 84% of the total organic acids analysed in sugarcane juice followed by malic acid with 14%. Oxalic, glutaric, alpha-ketoglutaric and citric acids were found in levels lower than 1% of total organic acids. The content of trans-aconitic, malic and succinic acids decreased with the stage of maturity while malonic acid increased. No significant differences were observed among the varieties studied in relation to trans-aconitic acid content.Os teores dos ácidos trans-aconítico, málico, malônico e succínico foram determinados no caldo de cana das variedades IAC 58-480, RB 73-5275 e NA 56-79, em quatro estádios de maturidade (11, 12, 13 e 14 meses). O ácido trans-aconítico constituiu cerca de 84% do total dos ácidos orgânicos seguido pelo ácido málico com 14%. Os ácidos oxálico, glutárico, alfa-cetoglutárico e cítrico foram encontrados em níveis inferiores a 1%. Os níveis dos ácidos succínico, málico e trans-aconítico diminuíram com a maturidade da planta enquanto os de malônico aumentaram. Não foram encontradas diferenças significativas entre as variedades estudadas em relação aos teores de ácido trans-aconítico
Influence of a single regional list for corneal transplantation on the eye bank of a university hospital
PURPOSE: To evaluate how the implantation of a single regional list for corneal transplants influenced an eye bank of a university hospital. To analyze the influence of the regional list on the corneas (procurement and destiny), the number of transplantations made and the average waiting time for surgery. METHODS: A retrospective study was made to compare the records of patients who underwent penetrating keratoplasty and also the data of the eye bank of the Medical School of São José do Rio Preto, São Paulo, Brazil. The study compared the data of the service one year before and one year after the creation of the single regional list. RESULTS: The number of transplantations increased from 60 to 92 procedures. The monthly average of directly acquired corneas increased from 13.83 + 6.57 to 18.16 + 4.8 (p-value = 0.07). The number of corneas sent to other institutions was greater than the number of corneas received from other eye banks (p-value = 0.003). There was no significant difference between the waiting time for surgery before and after the creation of the list except for the period of adaptation. CONCLUSIONS: This eye bank served as a supplier of corneas for other institutions. By the end of the first year of operation of the single regional list, there was no alteration in the waiting time as compared to that before its creation. Nonetheless, a tendency of homogenization in the waiting time for penetrating keratoplasty among the patients was observed.OBJETIVO: Avaliar como a implantação do sistema de lista única para transplantes de córnea influenciou um Banco de Olhos vinculado a um hospital escola. Analisar sua interferência nas córneas (captação e destino), no número de transplantes realizados e também na média de tempo de espera pela cirurgia. MÉTODOS: Foi realizado estudo retrospectivo, avaliando os prontuários dos pacientes submetidos a ceratoplastia penetrante e também os dados do Banco de Olhos da Faculdade de Medicina de São José do Rio Preto - SP. O estudo comparou dados relativos ao funcionamento do serviço por um ano antes e após a criação da lista única. RESULTADOS: O número de cirurgias aumentou de 60 para 92 cirurgias. A média mensal de córneas retiradas aumentou de 13,83 ± 6,57 para 18,16 ± 4,80 (p=0,07). O número de córneas enviadas por esta instituição foi maior que o número de córneas recebidas de outros serviços (p=0,003). Não houve diferença significativa entre o tempo de espera pela cirurgia antes e após a criação da fila única (desconsiderando o período de cadastramento). CONCLUSÕES: Este Banco de Olhos funcionou como fornecedor de córneas para outras instituições. Após seu primeiro ano de funcionamento, a implantação da lista única não alterou o tempo de espera dos pacientes pela cirurgia. Apesar disso, evidenciou-se uma tendência à homogeneização do tempo de espera pela ceratoplastia penetrante entre os pacientes.Faculdade de Medicina de São José do Rio Preto Departamento de OftalmologiaUniversidade Federal de São Paulo (UNIFESP) setor de Lente de ContatoFaculdade de Medicina de São José do Rio Preto Departamento de Oftalmologia Setor de Córnea e Moléstias ExternasFaculdade de Medicina de São José do Rio Preto serviço de OftalmologiaUNIFESP, setor de Lente de ContatoSciEL
Exclusion of Class III malocclusion candidate loci in Brazilian families
The role played by genetic components in the etiology of the Class III phenotype, a class of dental malocclusion, is not yet understood. Regions that may be related to the development of Class III malocclusion have been suggested previously. The aim of this study was to search for genetic linkage with 6 microsatellite markers (D1S234, D4S3038, D6S1689, D7S503, D10S1483, and D19S566), near previously proposed candidate regions for Class III. We performed a two-point parametric linkage analysis for 42 affected individuals from 10 Brazilian families with a positive Class III malocclusion segregation. Analysis of our data indicated that there was no evidence for linkage of any of the 6 microsatellite markers to a Class III locus at = zero, with data supporting exclusion for 5 of the 6 markers evaluated. The present work reinforces that Class III is likely to demonstrate locus heterogeneity, and there is a dependency of the genetic background of the population in linkage studies
The contribution of metacognitions and attentional control to decisional procrastination
Earlier research has implicated metacognitions and attentional control in procrastination and self-regulatory failure. This study tested several hypotheses: (1) that metacognitions would be positively correlated with decisional procrastination; (2) that attentional control would be negatively correlated with decisional procrastination; (3) that metacognitions would be negatively correlated with attentional control; and (4) that metacognitions and attentional control would predict decisional procrastination when controlling for negative affect. One hundred and twenty-nine participants completed the Depression Anxiety Stress Scale 21, the Meta-Cognitions Questionnaire 30, the Attentional Control Scale, and the Decisional Procrastination Scale. Significant relationships were found between all three attentional control factors (focusing, shifting, and flexible control of thought) and two metacognitions factors (negative beliefs concerning thoughts about uncontrollability and danger, and cognitive confidence). Results also revealed that decisional procrastination was significantly associated with negative affect, all measured metacognitions factors, and all attentional control factors. In the final step of a hierarchical regression analysis only stress, cognitive confidence, and attention shifting were independent predictors of decisional procrastination. Overall these findings support the hypotheses and are consistent with the Self-Regulatory Executive Function model of psychological dysfunction. The implications of these findings are discussed
A ECONOMIA POLÍTICA DA CONVERSIBILIDADE DO REAL: UMA CRÍTICA A ARIDA
This paper aims at discussing critically Pérsio Arida's proposal of adopting full currency convertibility in Brazil. Arida (2003a, 2003b, 2004) points out that currency convertibility would make for lower domestic interest rates in Brazil, as well as for lower interest rates for the Brazilian external bonds. Besides, currency convertibility would stabilize capital flows, as well as exchange rate volatility in Brazil. We argue in this paper that this proposal does not lead necessarily either to less exchange rate volatility, or to lower interest rates. Finally, we close the paper by presenting some alternatives in terms of capital controls in Brazil.
Autofluorescence and spectral-domain optical coherence tomography of optic disk melanocytoma
The authors report fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (OCT) findings of two consecutive patients who presented with optic disk melanocytoma (ODM). A retrospective study was performed by reviewing medical records and ophthalmic imaging examinations. Optical coherence tomography findings were sloped and brightly reflective anterior tumor surface, adjacent retinal desorganization and abrupt posterior optical shadowing. Vitreous seeds were found in one patient. Fundus autofluorescence revealed outstanding hypoautofluorescence at the tumor area and isoautofluorescence at the remaining retina. Optical coherence tomography findings of the reported cases are consistent with those reported in the reviewed literature. Fundus autofluorescence has been used in the assessment of choroidal melanocytic tumors, but not yet in melanocytomas. We assume that this is the first report of these findings and believe that when its pattern has become clearly defined, fundus autofluorescence will be a useful tool to avoid misdiagnosis in suspicious cases and for follow-up
- …