1,083 research outputs found

    Modeling Noisiness to Recognize Named Entities using Multitask Neural Networks on Social Media

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    Recognizing named entities in a document is a key task in many NLP applications. Although current state-of-the-art approaches to this task reach a high performance on clean text (e.g. newswire genres), those algorithms dramatically degrade when they are moved to noisy environments such as social media domains. We present two systems that address the challenges of processing social media data using character-level phonetics and phonology, word embeddings, and Part-of-Speech tags as features. The first model is a multitask end-to-end Bidirectional Long Short-Term Memory (BLSTM)-Conditional Random Field (CRF) network whose output layer contains two CRF classifiers. The second model uses a multitask BLSTM network as feature extractor that transfers the learning to a CRF classifier for the final prediction. Our systems outperform the current F1 scores of the state of the art on the Workshop on Noisy User-generated Text 2017 dataset by 2.45% and 3.69%, establishing a more suitable approach for social media environments.Comment: NAACL 201

    Residuos agroindustriales como fuente de nutrientes y compuestos fenólicos

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    El presente trabajo describe los nutrientes y compuestos fenólicos contenidos en diversos residuos agroindustriales (RAI). Los RAI pueden derivar en problemas que comprometen la alimentación y salud de las poblaciones más vulnerables si no son aprovechados adecuadamente. Por ello  es importante crear alternativas que contribuyan a contrarrestar el problema, desde la producción de alimentos hasta la mesa del consumidor. Los RAI de frutas, verduras, cereales y oleaginosas contienen nutrientes y compuestos fenólicos que pueden ser benéficos a la salud debido a sus efectos antioxidantes, antiinflamatorios, antidiabéticos, entre otros. Los RAI podrían también ser aplicados en el desarrollo de alimentos, debido a sus características tecnofuncionales como la capacidad de actuar como agentes gelificantes, emulsificantes, estabilizantes y espesantes. De acuerdo con lo anterior, el empleo de RAI para un segundo uso es prometedor, sin embargo, aún quedan algunos retos por resolver, tales como el escalamiento y la optimización de su extracción

    INTERACCIÓN DE COMPUESTOS FENÓLICOS Y FIBRA DIETARIA: CAPACIDAD ANTIOXIDANTE Y BIODISPONIBILIDAD

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    En los últimos años, la relación entre el consumo de frutas y la salud humana ha sido el punto focal de la investigación científica. Este interés se debe a la búsqueda específica de los compuestos contenidos en vegetales que proporcionan beneficios a la salud del consumidor (Palafox-Carlos et al., 2011). Las frutas, además de ser fuente de vitaminas, minerales y fibra, también son fuente rica en compuestos bioactivos conocidos como fitoquímicos. Los compuestos fenólicos (CF) son sustancias fitoquímicas que estando en bajas concentraciones en los alimentos, pueden prevenir algunos de los procesos implicados en el desarrollo de cáncer y enfermedades cardiovasculares (Denny y Buttriss, 2007). Sin embargo, la evidencia de su papel en la prevención de otras enfermedades degenerativas requiere de un mayor soporte científico

    Optimization of total anthocyanin content and antioxidant activity of a Hibiscus sabdariffa infusion using response surface methodology

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    Hibiscus sabdariffa L. calyces are underutilized sources of health-promoting anthocyanins. Infusions are the most common way to consume them, but because anthocyanins are thermosensitive, prolonged extraction times at high temperatures may reduce their bioactivities, suggesting the need to identify optimal preparation conditions. Response surface methodology was used to establish calyces-to-water ratio (X1: 1–20 g/100 mL), temperature (X2: 70–100 °C), and time (X3: 1–30 min) that would produce an infusion with optimized total anthocyanin content (TAC) and antioxidant activity. Under optimum conditions (X1=10 g/100 mL, X2=88.7 °C, and X3=15.5 min) TAC was 132.7±7.8 mg cyanidin-3-glucoside equivalents (C3G)/100 mL, and antioxidant activity was 800.6±69.9 (DPPH assay), and 1792.0±153.5 (ABTS assay) μmol Trolox equivalents (TE)/100 mL. Predicted and experimental results were statistically similar. Identifying ideal processing conditions can promote consumption of an H. sabdariffa-based functional beverage with high anthocyanin content and antioxidant activity that exert health-promoting bioactivities on the consumer

    Content of bioactive compounds and their contribution to antioxidant capacity during ripening of pineapple (Ananas comosus L.) cv Esmeralda

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    Pineapple (Ananas comosus L.) cv Esmeralda is a commercially important fruit with many bioactive compounds like vitamin C, β-carotene, phenolic compounds and flavonoids, which have been reported only for fruits of commercial maturity. Our objective was to evaluate changes in concentration of main pineapple bioactives, their contribution to total antioxidant capacity and enzyme activities of phenylalanine ammonia lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POD) during pineapple ripening. Fruits were grouped into four ripening stages (RS) according to their weight, size and percentage of yellow skin color (RS1: 100% green, RS2: up to 30% yellow, RS3: 30% - 75% yellow, RS4: 75% - 100% yellow). Vitamin C content initially increased, and decreased at RS4; β-carotene, phenolics and antioxidant capacity increased gradually. Phenolics contributed over 40% of antioxidant capacity, followed by vitamin C and β-carotene. Major phenolic compounds identified were gallic acid, catechin and epicatechin. PAL and POD activity increased with ripening and correlated with concentration of phenolics. No PPO activity was quantified. We concluded that ripening of pineapple cv Esmeralda alters the concentration of bioactive compounds. Phenolic compounds, particularly gallic acid, exert the most antioxidant capacity during all RS, even if other compounds have higher concentrations
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