Mathematical modeling of area under the curve assessment criteria to quantify the antioxidant and pro-oxidant capacity: Coffee extracts as a case study

35 páginas, 5 figuras, 2 tablasThe development of a convenient mathematical application for testing the antioxidant and pro-oxidant capacity is essential in order to investigate potential sources of new agents and processes. In this regard, authors use the standardized values of the area under the curve of a kinetic profile of a dose-response agent, as a way to bypass the complex process of analyzing the kinetic variations of agents. In general, linear approaches are used, but such patterns frequently lead to unreliable results and misinterpretations, making it extremely difficult to compare the results from different assays. In this work, we have demonstrated the non-linearity of the dose-response area under the curve assessment criteria by means of simulations. A simple non-linear dose-response model was developed to describe the accurately response. As case study, experimental data of extracts of unroasted coffee beans from five different country-climate locations for the two most common coffee varieties (Robusta and Arabica) were obtained using the β-carotene and crocin bleaching in vitro assays. Their antioxidant capacity was analyzed in detail and compared with commercial standards. The results shows that the antioxidant capacity was greater than some of the commercial standards in terms of its maximum capacity, while when the analyses are based on rate parameters, the coffee extracts show between 6 to 40 times lower values than the standard antioxidants. In addition, to illustrate the advantages of using the standardized area units and the mathematical model developed, other more complex scenarios were recreated. We believe that the model application developed provides a simple alternative to summarize in meaningful parameters that characterize the response, it facilitates rigorous comparisons among the effects of different compounds and experimental approaches and it helps to comprehend multi-variable scenariosThe authors wish to thank CSIC (Intramural project: 200930I183) and Ministerio de Ciencia e Innovación (project CTM2010-18411, co-financed with FEDER funds by European Union) for financial support. Miguel Angel Prieto Lage was awarded one grant from the JAE predoctoral program co-financed by the CSIC and European Social Fund (ESF)Peer reviewe

Hydrolysis optimization of mannan, curdlan and cell walls from Endomyces fibuliger grown in mussel processing wastewaters

The aim of this report was to optimize the hydrolysis of the cell walls (CWs) from the yeast Endomyces fibuliger grown in mussel processing wastewaters (MPW) to establish a more accurate protocol for analyzing the composition of the monosaccharides in these CWs. Therefore, a kinetic study of CW hydrolysis and polysaccharide standards (mannan and curdlan) was performed to determine the effect of different temperatures and trifluoroacetic acid (TFA) concentrations on this process. In all cases, the experimental data were fit satisfactorily to Saeman's equation with an Arrhenius relation between rate constants and the temperature effect. Optimal conditions for curdlan and mannan hydrolysis were achieved with 70% TFA at 100 °C for 2.3 h and 50% TFA at 100 °C for 2.6 h, respectively. The best operating options for CW hydrolysis were 100 °C/70% TFA for 4.58 h, 100 °C/50% TFA for 4.08 h and 100 °C/70% TFA for 3.27 h for the maximum production of glucose, mannose and reducing sugars, respectively.Mr. Miguel Angel Prieto Lage was awarded with two grants from the Lucas Labrada and María Barbeito programs financed by the Xunta de Galicia. We wish to thank the CSIC (Intramural Project: 200930I183) and Xunta de Galicia (Programa de consolidación de unidades de investigación 2008–2010, IN845B-2010/004) for financial support.Peer reviewe

Robust Traffic Sign Detection by means of Vision and V2I Communications

14th International IEEE Annual Conference on Intelligent Transportation Systems - ITSC, , 05/10/2011-07/10/2011, Washington DC, Estados UnidosThis paper presents a complete traffic sign recognition system, including the steps of detection, recognition and tracking. The Hough transform is used as detection method from the information extracted in contour images, while the proposed recognition system is based on Support Vector Machines (SVM), and is able to recognize up to one hundred of the main road signs. Besides a novel solution to the problem of discarding detected signs that do not pertain to the host road is proposed, for that purpose vehicle-to-infrastructure (V2I) communication and stereo information is used. This paper presents plenty of tests in real driving conditions, both day and night, in which a high success rate and low number of false negatives and true positives were obtained, and an average runtime of 35 ms, allowing real-time performance

Límite y percepción en la arquitectura: el caso del IVVSA

Peer Reviewe

Variations in breathing patterns increase low frequency contents in HRV spectra

This paper shows that variations in breathing patterns broaden heart rate variability (HRV) spectral bands and increase the power amplitude of low-frequency bands. Because of these influences, spectral markers for HRV signals, such as the quotient between spectral power at different frequency bands, should be compared only under controlled breathing conditions or after considering the effect of variations in breathing patternsPeer Reviewe

A New Life for Forest Resources: The Commons as a Driver for Economic Sustainable Development—A Case Study from Galicia

Communal forests are a unique land tenure system and comprise a singular legal category in Galicia. Their persistence over time demonstrates that this community-owned resource has overcome the “tragedy of the commons”, showing their capability to successfully develop self-governing institutions. However, communal forests have rarely been studied through the lens of economics. This minimizes the opportunity to explore to what extent communities of communal forests might be a driving force of general well-being, citizen empowerment, equity, employment, and local development. In this paper, we focus on this gap and address the opportunities. We detail this special ownership structure that allows residents of rural areas to exploit the forest as if they were a single owner. Moreover, we highlight the potential of communal forests to exploit local resources far beyond extractive processes, enabling the generation of greater added value to the economy while favoring a responsible treatment of resources. This enables productive activity integrated with the rest of the primary sector, while allowing for the maintenance of the population and supporting the local economy. Our results reveal a set of inefficiencies that can jeopardize common forest opportunities to become a sustainable economic activity, such as underqualified management, a low level of interest and commitment among community members, and excessive focus on logging. Thus, we propose several actions to improve collective engagement and active membership to better manage Galicia’s forestsS

Evolution of caries and fluorosis in schoolchildren of the Canary Islands (Spain) : 1991, 1998, 2006

The aim of this work is to assess the evolution of caries and fluorosis prevalence and indices at 7 and 12 years of age in the Canary Islands through three cross epidemiological studies conducted in 1991, 1998 and 2006. The three studies followed a similar methodology, using the WHO diagnosis criteria and indications, except for the assessment of fluorosis, which was measured with the ?Thylstrup and Fejerskov? index. The examining dentists were trained and calibrated in an area with high endemic fluorosis. The three studies took a sample of 1000 students for each age group. At 7 years of age, the decayed, and filled teeth (dft) varied from 1.42 in 1991 to 1.14 in 1998 and 1.37 in 2006. At 12 years of age, the Decayed, Missing, and Filled Teeth (DMFT) went from 1.86 to 1.21 and 1.51 in the three studies respectively and the significant caries index (SiC) went from 4.28 to 3.15 and 3.72. At this age, the Filled Rate rose from 24.05% in 1991 to 30.43% in 1998 and to 37.20% in 2006. In relation to fluorosis, at 12 years of age the percentage of healthy or fluorosis-free schoolchildren in the Canary Islands between the first and the second studies went down from 73% to 61.3% and went up to 78.5% in 2006, with a noticeable fall in the prevalence of children with severe and moderate fluorosis. Despite the fluctuations of caries shown in the three studies, at 12 years of age the Canary Islands have remained in the low level of caries of the WHO classification from 1991 up to now. The evolution in the prevalence of dental fluorosis shows the effect of the measures taken, 10 years after they were started

Trendscouting: las tendencias en el mundo de la moda

Se realiza una identificación y análisis de las necesidades de información relacionadas con la exploración de nuevas tendencias de moda textil por los cazatendencias o Coolhunters, así como de los recursos de información adecuados para su satisfacción. La metodología ha consistido en la reflexión sobre la experiencia de la autora, la realización de entrevistas a personas vinculadas con el mundo de la moda y la búsqueda de recursos de información en Internet sobre Coolhunting. Se concluye con la presentación de una matriz que permite establecer y valorar la relación entre las necesidades de información y los recursos identificados. El hermetismo de los profesionales del Trendscounting dificulta la realización de estudios de este tipo