Rapid determination of furosemide by combined spot test/diffuse reflectance spectroscopy to detect doping in sport

This paper describes the development and application of a simple, cheap, and clean method for the quantification of furosemide in urine samples from athletes, to detect doping, using a combined spot test/diffuse reflectance spectroscopy procedure. The method is based on the complexation reaction of furosemide (5-(aminosulfonyl)-4-chloro-2-((furanylmethyl)amino)benzoic acid, dissolved in ethanol, with FeCl3 and the surfactant dodecyltrimethylammonium bromide (DTAB) in aqueous solution, yielding a colored compound on the surface of a filter paper. The reagent concentrations were optimized using a chemometric experimental design. The reflectometric measurements of the complex formed were carried out at 477nm. The linear range obtained was 1.65-9.00×10-3molL-1 of furosemide (R=0.997), and the detection and quantification limits were 4.9×10-4 and 1.62×10-3molL-1, respectively. The proposed method was successfully applied in the analysis of furosemide in spiked urine, demonstrating that it is a reliable alternative method for the detection of furosemide doping in sport. © 2012 Elsevier B.V..

Fruit color and contrast in seasonal habitats - a case study from a cerrado savanna

Communication contributes to mediate the interactions between plants and the animals that disperse their genes. As yet, seasonal patterns in plant-animal communication are unknown, even though many habitats display pronounced seasonality e.g. when leaves senescence. We thus hypothesized that the contrast between fruit displays and their background vary throughout the year in a seasonal habitat. If this variation is adaptive, we predicted higher contrasts between fruits and foliage during the fruiting season in a cerrado-savanna vegetation, southeastern Brazil. Based on a six-year data base of fruit ripening and a one-year data set of fruit biomass, we used reflectance measurements and contrast analysis to show that fruits with distinct colors differed in the beginning of ripening and the peak of fruit biomass. Black, and particularly red fruits, that have a high contrast against the leaf background, were highly seasonal, peaking in the wet season. Multicolored and yellow fruits were less seasonal, not limited to one season, with a bimodal pattern for yellow ones, represented by two peaks, one in each season. We further supported the hypothesis that seasonal changes in fruit contrasts can be adaptive because fruits contrasted more strongly against their own foliage in the wet season, when most fruits are ripe. Hence, the seasonal variation in fruit colors observed in the cerrado-savanna may be, at least partly, explicable as an adaptation to ensure high conspicuousness to seed dispersers. © 2013 The Authors.

Caracterização de filmes finos de ZnO dopados com Al e Mn depositados em substrato vítreo pelo método de Spray Pirólise

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Magnetic susceptibility and diffuse reflectance spectroscopy to characterize the spatial variability of soil properties in a Brazilian Haplustalf

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In-Office dental bleaching efficacy assessment in function of the light exposure regime by digital colometric reflectance spectroscopy

In-office dental bleaching has been subject of several studies. Generally those studies quantify through visual analysis, the shade reduction of the teeth submitted to different bleaching protocols (light sources, bleaching agent concentrations and irradiation time). The objective of this work is the determination of the influence of four irradiation protocols on the obtainment of better aesthetic results using a colorimetric spectrophotometer that quantifies color changes in each situation imposed. Forty bovine incisors were selected in function of similar anatomic characteristics; a concentrated coffee solution was used to stain the teeth. A commercial spectrophotometer was used to measure the color changes during evolution of the experiment (stain and bleaching phases) and the obtained data was analyzed by the ANOVA test. The obtained data showed the evolution of teeth color during the staining period, as well as, the color reduction that each bleaching protocol achieved. Based on our findings it is possible to conclude that bleaching protocols with larger irradiation periods did not showed significant differences when compared with shorter irradiation protocols, in that way the use of protocols with 30 min or more of consecutive irradiation are not clinically justified and also can cause several side effects.

Mapping of clay, iron oxide and adsorbed phosphate in Oxisols using diffuse reflectance spectroscopy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Calibration of a Species-Specific Spectral Vegetation Index for Leaf Area Index (LAI) Monitoring: Example with MODIS Reflectance Time-Series on Eucalyptus Plantations

The leaf area index (LAI) is a key characteristic of forest ecosystems. Estimations of LAI from satellite images generally rely on spectral vegetation indices (SVIs) or radiative transfer model (RTM) inversions. We have developed a new and precise method suitable for practical application, consisting of building a species-specific SVI that is best-suited to both sensor and vegetation characteristics. Such an SVI requires calibration on a large number of representative vegetation conditions. We developed a two-step approach: (1) estimation of LAI on a subset of satellite data through RTM inversion; and (2) the calibration of a vegetation index on these estimated LAI. We applied this methodology to Eucalyptus plantations which have highly variable LAI in time and space. Previous results showed that an RTM inversion of Moderate Resolution Imaging Spectroradiometer (MODIS) near-infrared and red reflectance allowed good retrieval performance (R-2 = 0.80, RMSE = 0.41), but was computationally difficult. Here, the RTM results were used to calibrate a dedicated vegetation index (called "EucVI") which gave similar LAI retrieval results but in a simpler way. The R-2 of the regression between measured and EucVI-simulated LAI values on a validation dataset was 0.68, and the RMSE was 0.49. The additional use of stand age and day of year in the SVI equation slightly increased the performance of the index (R-2 = 0.77 and RMSE = 0.41). This simple index opens the way to an easily applicable retrieval of Eucalyptus LAI from MODIS data, which could be used in an operational way.

Bilipid membrane phase characterization by reflectance anisotropy spectroscopy (RAS)

In this work we propose the use of experimental and theoretical reflectance anisotropy spectra (RAS) as a new tool to identify structural and dynamical aspects of the bilipid membrane and its various constituent molecules. The role of geometric details at the atomic level and macroscopic quantities, such as the membrane curvature and tilt for the different gel phases, in the theoretical RAS spectra (using Kohn-Sham density functional theory (KS-DFT)) are presented. Then the results are compared to the experimentally measured spectra taken from other techniques.

Bilipid Membrane Phase Characterization by Reflectance Anisotropy Spectroscopy (RAS)

In this work we propose the use of experimental and theoretical reflectance anisotropy spectra (RAS) as a new tool to identify structural and dynamical aspects of the bilipid membrane and its various constituent molecules. The role of geometric details at the atomic level and macroscopic quantities, such as the membrane curvature and tilt for the different gel phases, in the theoretical RAS spectra (using Kohn-Sham density functional theory (KS-DFT)) are presented. Then the results are compared to the experimentally measured spectra taken from other techniques.

Validazione e applicazioni cliniche della metodica NIRA (Near Infrared Reflectance Analysis) per la valutazione del contenuto nutrizionale del latte materno in terapia intensiva neonatale

Phase 1: To validate Near-Infrared Reflectance Analysis (NIRA) as a fast, reliable and suitable method for routine evaluation of human milk’s nitrogen and fat content. Phase 2: To determine whether fat content, protein content and osmolality of HM before and after fortification may affect gastroesophageal reflux (GER) in symptomatic preterm infants. Patients and Methods: Phase 1: 124 samples of expressed human milk (55 from preterm mothers and 69 from term mothers) were used to validate NIRA against traditional methods (Gerber method for fat and Kjeldhal method for nitrogen). Phase 2: GER was evaluated in 17 symptomatic preterm newborns fed naïve and fortified HM by combined pH/intraluminal-impedance monitoring (pH-MII). HM fat and protein content was analysed by a Near-Infrared-Reflectance-Analysis (NIRA). HM osmolality was tested before and after fortification. GER indexes measured before and after fortification were compared, and were also related with HM fat and protein content and osmolality before and after fortification. Results: Phase 1: · A strong agreement was found between traditional methods’ and NIRA’s results (expressed as g/100 g of milk), both for fat and nitrogen content in term (mean fat content: NIRA=2.76; Gerber=2.76; mean nitrogen content: NIRA=1.88; Kjeldhal =1.92) and preterm (mean fat content: NIRA=3.56; Kjeldhal=3.52; mean nitrogen content: NIRA=1.91; Kjeldhal =1.89) mother’s milk. · Nitrogen content of the milk samples, measured by NIRA, ranged from 1.18 to 2.71 g/100 g of milk in preterm milk and from 1.48 to 2.47 in term milk; fat content ranged from 1.27 to 6.23 g/100 g of milk in preterm milk and from 1.01 to 6.01 g/100 g of milk in term milk. Phase 2: · An inverse correlation was found between naïve HM protein content and acid reflux index (RIpH: p=0.041, rho=-0.501). · After fortification, osmolality often exceeded the values recommended for infant feeds; furthermore, a statistically significant (p<.05) increase in non acid reflux indexes was observed. Conclusions: NIRA can be used as a fast, reliable and suitable tool for routine monitoring of macronutrient content of human milk. Protein content of naïve HM may influence acid GER in preterm infants. A standard fortification of HM may worsen non acid GER indexes and, due to the extreme variability in HM composition, may overcome both recommended protein intake and HM osmolality. Thus, an individualized fortification, based on the analysis of the composition of naïve HM, could optimize both nutrient intake and feeding tolerance.

Carbon pools and poverty peaks in Lao PDR

Reducing Emissions from Deforestation and forest Degradation and enhancing forest carbon stocks in developing countries (REDD+) is heavily promoted in Laos. REDD+ is often perceived as an opportunity to jointly address climate change and poverty and, therefore, could come timely for Laos to combine its prominent national target of poverty eradication with global climate mitigation efforts. Countrywide planning of the right approaches to REDD+ combined with poverty alleviation requires knowledge of the spatial combination of poverty and carbon stocks at the national level. This study combined spatial information on carbon stored in vegetation and on poverty and created carbon-poverty typologies for the whole country at the village level. We found that 11% of the villages of Laos have high to very high average village-level carbon stock densities and a predominantly poor population. These villages cover 20% of the territory and are characterized by low population density. Shifting cultivation areas in the northwestern parts of the country have a higher carbon mitigation potential than areas in the central and eastern highlands due to a more favorable climate. Finally, we found that in Laos the majority (58%) of poor people live in areas with low carbon stock densities without major potential to store carbon. Accordingly, REDD+ cannot be considered a core instrument for poverty alleviation. The carbon-poverty typologies presented here provide answers to basic questions related to planning and managing of REDD+. They could serve as a starting point for the design of systems to monitor both socioeconomic and environmental development at the national level.