Development of a Novel Biosensor Using Cationic Antimicrobial Peptide and Nickel Phthalocyanine Ultrathin Films for Electrochemical Detection of Dopamine

The antimicrobial peptide dermaseptin 01 (DS 01), from the skin secretion of Phyllomedusa hypochondrialis frogs, was immobilized in nanostructured layered films in conjunction with nickel tetrasulfonated phthalocyanines (NiTsPc), widely used in electronic devices, using layer-by-layer technique. The films were used as a biosensor to detect the presence of dopamine (DA), a neurotransmitter associated with diseases such as Alzheimer's and Parkinson's, with detection limits in the order of 10−6 mol L−1. The use of DS 01 in LbL film generated selectivity in the detection of DA despite the presence of ascorbic acid found in biological fluids. This work is the first to report that the antimicrobial peptide and NiTsPc LbL film exhibits electroanalytical activity to DA oxidation. The selectivity in the detection of DA is a fundamental aspect for the development of electrochemical sensors with potential applications in the biomedical and pharmaceutical industries

Development of a Novel Biosensor Using Cationic Antimicrobial Peptide and Nickel Phthalocyanine Ultrathin Films for Electrochemical Detection of Dopamine

The antimicrobial peptide dermaseptin 01 (DS 01), from the skin secretion of Phyllomedusa hypochondrialis frogs, was immobilized in nanostructured layered films in conjunction with nickel tetrasulfonated phthalocyanines (NiTsPc), widely used in electronic devices, using layer-by-layer technique. The films were used as a biosensor to detect the presence of dopamine (DA), a neurotransmitter associated with diseases such as Alzheimer's and Parkinson's, with detection limits in the order of 10−6 mol L−1. The use of DS 01 in LbL film generated selectivity in the detection of DA despite the presence of ascorbic acid found in biological fluids. This work is the first to report that the antimicrobial peptide and NiTsPc LbL film exhibits electroanalytical activity to DA oxidation. The selectivity in the detection of DA is a fundamental aspect for the development of electrochemical sensors with potential applications in the biomedical and pharmaceutical industries

Sistema de alerta com base em estudo teórico-experimental de dispersão de poluentes solúveis em rios

Information about capacity of transport and dispersion of soluble pollutants in natural streams are important in the management of water resources, especially in planning preventive measures to minimize the problems caused by accidental or intentional waste, in public health and economic activities that depend on the use of water. Considering this importance, this study aimed to develop a warning system for rivers, based on experimental techniques using tracers and analytical equations of one-dimensional transport of soluble pollutants conservative, to subsidizing the decision-making in the management of water resources. The system was development in JAVA programming language and MySQL database can predict the travel time of pollutants clouds from a point of eviction and graphically displays the temporal distribution of concentrations of passage clouds, in a particular location, downstream from the point of its launch.Informações sobre a capacidade de transporte e dispersão de poluentes solúveis em cursos de água naturais são importantes no gerenciamento dos recursos hídricos, principalmente no planejamento preventivo de medidas que visem a minimizar problemas à saúde pública e às atividades econômicas que dependem do uso da água, ocasionados por despejos acidentais ou intencionais. Considerando tal importância, este trabalho teve como objetivo desenvolver um sistema de alerta para rios, com base em resultados experimentais, utilizando técnicas de traçadores e equações analíticas de transporte unidimensional de poluentes solúveis conservativos, visando a subsidiar a tomada de decisão no gerenciamento dos recursos hídricos. O sistema desenvolvido em linguagem de programação JAVA e banco de dados MySQL permite prever o tempo de percurso da nuvem de poluentes a partir de um ponto de despejo de um poluente e apresenta, graficamente, a distribuição temporal de concentrações da passagem da nuvem, em um determinado local, à jusante do ponto do seu lançamento

Multi-site clinical assessment of Complete Revitalens MPDS in 2981 contact lens wearers across Europe and USA

(MPDS), Complete Revitalens (RevitaLens OcuTec in the US Market), for soft contact lens care in a large “real practice” setting. Method: This is an international multi-center, open-label assessment carried out in 10 countries across Europe and in the USA. Up to 10 subjects who were currently wearing soft contact lenses for at least 1 year and using a MPS as a lens care system were included at each investigational site. Results: Data were collected from 996 European and 1985 American wearers, 75% of those patients wore silicone hydrogel contact lenses. Approximately 94% found the new MPDS “somewhat more effective” to “much more effective” in keeping contact lenses feeling clean and 88% found the new MPDS to be somewhat more effective to much more effective in keeping their lenses feeling comfortable in the evening. Over 93% reported an improvement in vision clearness in the evening after approximately 1 month while using the new MPDS. Wearers with grade 2, 3 or 4 of severity decreased by 11.3, 6.4 and 9.8% over 1 month period for redness, burning and irritation, respectively. After approximately 1 month 83% of wearers declared that they would prefer to use the new MPDS. Conclusions: Over 88% felt their lenses were somewhat to much more comfortable at the end-of-day and 94% found the new MPDS to be somewhat to much more effective in keeping their lenses feeling clean compared to their previous care system.The authors wish to thank the eye care practitioners participating in this study across Europe and USA. The D'Ellis Group for the statistical support and Rafael Guerrero and Will Heydorn from Abbott Medical Optics, Inc. for their contributions in planning and coordinating the European and American branches of the study, respectively. The authors declare no proprietary or financial interest in any of the materials mentioned in this article. This study has been sponsored by Abbott Medical Optics Inc. These results were presented to the American Academy of Optometry Boston, 12-15th, 2011

Ocular dominance and visual function testing

To show the distribution of ocular dominance as measured with sensory and eye sighting methods and its potential relationship with high and low contrast LogMAR visual acuity in presbyopic subjects. Method. Forty-four presbyopes (48.5 ± 3.5 years) participated in this study. Ocular dominance was determined by eye sighting (hole-in-card) and sensorial (+1.50 D lens induced blur) methods. According to the dominance detected with each method (RE: right eye or LE: left eye), patients were classified in dominance type 1 (RE/RE), type 2 (RE/LE), type 3 (LE/RE) and type 4 (LE/LE). Results. Baseline refractive error (MSE) was RE:−0.36 ± 1.67 D and LE:−0.35 ± 1.85 D (P= 0.930). RE was the dominant eye in 61.4% and 70.5% of times as obtained from sensorial and sighting methods, respectively. Most frequent dominance was of type 1 (52.3%), in this case the RE showed statistically significant better distance low contrast LogMAR VA (0.04 LogMAR units) compared to the LE (P < 0.05 ). Conclusions. The dominance was more frequent in RE in this sample. The eye sighting and sensorial methods to define ocular dominance agreed in more than half of cases. Amount of MSE was not significantly different between dominant and non-dominant eye. But in case of right dominance, the RE presented better distance low contrast VA compared to the LE.Purpose. To show the distribution of ocular dominance as measured with sensory and eye sighting methods and its potential relationship with high and low contrast LogMAR visual acuity in presbyopic subjects. Method. Forty-four presbyopes (48.5 +/- 3.5 years) participated in this study. Ocular dominance was determined by eye sighting (hole-in-card) and sensorial (+1.50D lens induced blur) methods. According to the dominance detected with each method (RE: right eye or LE: left eye), patients were classified in dominance type 1 (RE/RE), type 2 (RE/LE), type 3 (LE/RE) and type 4 (LE/LE). Results. Baseline refractive error (MSE) was RE:-0.36 +/- 1.67D and LE:-0.35 +/- 1.85D (P = 0.930). RE was the dominant eye in 61.4% and 70.5% of times as obtained from sensorial and sighting methods, respectively. Most frequent dominance was of type 1 (52.3%), in this case the RE showed statistically significant better distance low contrast LogMAR VA (0.04 LogMAR units) compared to the LE (P < 0.05). Conclusions. The dominance was more frequent in RE in this sample. The eye sighting and sensorial methods to define ocular dominance agreed in more than half of cases. Amount of MSE was not significantly different between dominant and non-dominant eye. But in case of right dominance, the RE presented better distance low contrast VA compared to the LE.Present study has been supported by Fundacao para a Ciencia e Tecnologia (FCT) under Contract PTDC/SAU-BEB/098392/2008. The authors declare that they do not have any proprietary or financial interests in any of the materials mentioned in this paper. The present work has been presented in part at the 8th International Conference of Optometry (CIOCV'2011) at University of Minho (9-10 April, Braga, Portugal)

Exploring the Elastic Properties and Fracture Patterns of Me-Graphene Monolayers and Nanotubes through Reactive Molecular Dynamics Simulations

Me-graphene (MeG) is a novel two-dimensional (2D) carbon allotrope. Due to its attractive electronic and structural properties, it is important to study the mechanical behavior of MeG in its monolayer and nanotube topologies. In this work, we conducted fully atomistic reactive molecular dynamics simulations using the Tersoff force field to investigate their mechanical properties and fracture patterns. Our results indicate that Young's modulus of MeG monolayers is about 414 GPa and in the range of 421-483 GPa for the nanotubes investigated here. MeG monolayers and MeGNTs directly undergo from elastic to complete fracture under critical strain without a plastic regime.Comment: 10 pages, 01 table, and 05 figure

Radiometric characterization of a novel LED array system for visual assessment

Light that enters the eye can be distorted due to several factors leading to a poor visual performance. The purpose of this paper is to describe and characterize the light-emitting diode (LED) display system to be used in a new device to assess visual quality under high glare conditions. The device has a central white LED and surrounding white LEDs distributed in a radial manner. Each LED is controlled independently using special designed software. The spectral power distribution and color of the LEDs were assessed at different voltage intensities to test the response in terms of output luminance and spectral distribution. It was found that the typical maximum luminance was about 2800 cd/m2 and 6 cd/m2 for the central and surrounding LEDs, respectively. Their color was found to be within the ΔE⁄ ab range of 2.6 and 0.23, respectively, if the minimum and maximum intensities are considered. The characterization of this device was proved successfully, which might indicate its usefulness in future visual assessments.This study has been funded by FEDER through the COMPTETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of projects PTDC/SAU-BEB/098391/2008, PTDC/SAU-BEB/098392/2008 and the Strategic Project PEST-C/FIS/UI607/2011

Chlorophyll fluorescence as a tool to select salinity-tolerant cowpea genotypes

The use of saline water reduces the growth and productivity of crops, so the need for techniques that make possible the use of this resource such as the use of salinity tolerant genotypes and efficient selection methods are of great importance. Thus, this study aimed to evaluate the tolerance of cowpea (Vigna unguiculata L. Walp.) genotypes to salt stress, through the chlorophyll fluorescence analysis. The experiment was conducted in a protected environment at the Federal University of Campina Grande, Paraíba, Brazil, using a completely randomized design in a 2 x 10 factorial arrangement, with three replications, consisting of two levels of irrigation water salinity (0.6 and 5.1 dS m-1) and ten cowpea genotypes: (G1: MNCO1-649F-2-1, G2: MNCO3-736F-2, G3: PINGO DE OURO-1-2, G4: BRS GURGUÉIA, G5: BRS MARATAOÃ, G6: MNCO2-676F-3, G7: MNCO2-683F-1, G8: MNCO3-737F-5-4, G9: MNCO3-737F-5-9, and G10: BRS TUMUCUMAQUE). The stem length, stem diameter, SPAD index, and chlorophyll fluorescence transients were evaluated. The G2 and G4 genotypes had the lowest reductions in the growth, stem diameter, initial fluorescence, and primary and maximum photochemical efficiency of PSII, proving to be tolerant to salinity. Chlorophyll fluorescence is a tool that can be used in the selection of salinity-tolerant cowpea genotypes