103 research outputs found

    Optimización de la extracción de aceite de semilla de dátil mediante la ayuda de tecnologías hidrotermales y de ultrasonido

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    The date seed is a by-product from the date industry. Its use as a source of added-value compounds is of great interest. Oil accounts for 5-13% of the seed’s weight. Soxhlet extraction with organic solvents is the traditional method for obtaining oil from seeds. In this work, hydrothermal pre-treatments and sonication are proposed to make the extraction a more environmentally friendly process. Factors such as sonication time and temperature and hexane-to-seed ratio (H/S) have been considered. Response surface methodology was applied for optimization. Hydrothermal treatments increased oil recovery. H/S was the most influential factor, and was close to 7 mL/g seeds for both samples. 71% recovery was achieved for native seeds after 15 min sonication at 45 ºC, and 80% for 180 ºC-treated seeds after 45 min at 35 ºC when compared to Soxhlet extraction. These conditions comply with our initial aim. Pre-treatments seem to have a negative effect on oil stability, although this observation needs to be confirmed.La semilla de dátil es un subproducto de la industria datilera. Su uso como fuente de compuestos de valor añadido sería muy interesante. El aceite representa el 5-13% del peso de la semilla. La extracción mediante Soxhlet con disolventes orgánicos es el método tradicional para obtener aceite de semillas. En este trabajo se proponen pretratamientos hidrotérmicos y sonicación para diseñar un proceso de extracción más respetuoso con el medio ambiente. Se han considerado factores como el tiempo y la temperatura de sonicación y la proporción hexano/semilla (H/S). La optimización del proceso se llevó a cabo por el método de superficie de respuesta. Los tratamientos hidrotérmicos aumentaron el porcentaje de recuperación. El factor más influyente fue H/S, y su valor óptimo estuvo cerca de 7 mL/g para ambas muestras. La recuperación óptima fue del 71% para las semillas sin tratamiento tras 15 min de sonicación a 45 ºC, y del 80% para las semillas tratadas a 180 ºC después de 45 min a 35 ºC. Estos resultados cumplen con nuestro objetivo inicial. Sin embargo, los pretratamientos parecen tener un efecto negativo sobre la estabilidad del aceite, lo que se confirmará en estudios posteriores

    Reutilización de objetos virtuales de aprendizaje en ambientes distribuidos

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    The use of TIC has now become one of the pillars of society and its influence on the educational process, taking into account the educational opportunities we can use TIC to promote learning and teaching, ie learning of any subject or skill that can help both the teacher and the student in the arduous search for knowledge. This project will focus on information technologies for education and that the person responsible for education seeking to develop processes and tools related to the generation of knowledge, which are impacted by the development of TICs. To disseminate knowledge collaboratively for educators who are part of the community of the LMS.El uso de las tecnologías de la información y la comunicación hoy en el presente ha llegado a ser uno de los pilares básicos de la sociedad, igual que su influencia en los procesos educativos, teniendo en cuenta las posibilidades educativas, para promover el aprender y el enseñar, es decir el aprendizaje de cualquier materia o habilidad que se puede facilitar tanto para el docente como el estudiante en la ardua búsqueda del conocimiento. Este artículo se centrara en tecnologías informáticas para la educación, ya que las persona encargadas de la enseñanza buscan desarrollar procesos y herramientas afines para la de generación de conocimiento, que son impactadas por el desarrollo de las TIC. Así poder difundir el conocimiento de manera colaborativa para los educadores que hacen parte de la comunidad de los LMS

    The relevance of biomaterials to the prevention and treatment of osteoporosis

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    Osteoporosis is a worldwide disease with a very high prevalence in humans older than 50. The main clinical consequences are bone fractures, which often lead to patient disability or even death. A number of commercial biomaterials are currently used to treat osteoporotic bone fractures, but most of these have not been specifically designed for that purpose. Many drug- or cell-loaded biomaterials have been proposed in research laboratories, but very few have received approval for commercial use. In order to analyze this scenario and propose alternatives to overcome it, the Spanish and European Network of Excellence for the Prevention and Treatment of Osteoporotic Fractures, ‘‘Ageing’’, was created. This network integrates three communities, e.g. clinicians, materials scientists and industrial advisors, tackling the same problem from three different points of view. Keeping in mind the premise ‘‘living longer, living better’’, this commentary is the result of the thoughts, proposals and conclusions obtained after one year working in the framework of this network

    Composición nutricional y actividad antioxidante de diferentes variedades de nueces (Juglans regia L.) de Nerpio (España) en comparación con variedades comerciales

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    In the Nerpio region (Albacete, Spain), endogenous walnut cultivars have been grown since ancient times. None of them has been chemically characterized to valorize them in comparison to commercial varieties. In this work, 47 native (N) and 7 foreign (F) walnut cultivars grown in Nerpio, and 13 commercial (C) samples were studied during three seasons. The average yield, moisture, and protein and oil contents were slightly lower in the N samples than in C. The composition of fatty acid suggested that the N walnuts could be more stable against oxidation due to their higher amount of MUFA and lower amount of PUFA. The biological protein value for the samples was similar but the antioxidant capacity marked important differences among them: N cultivars reached the highest scores, with intermediate F values. Local walnut varieties from Nerpio should be valorized on the basis of their potentially enhanced health benefits, although further studies must be developed on their phytochemicals.En Nerpio (Albacete, España) se cultivan tradicionalmente variedades locales de nueces que nunca han sido estudiadas con vistas a su puesta en valor frente a variedades comerciales. En este trabajo se han estudiado 47 variedades locales (N) y 7 extranjeras (F) cultivadas en Nerpio, además de 13 comerciales (C). Los valores medios encontrados para rendimiento, humedad, y contenidos graso y proteico fueron ligeramente inferiores en N. Debido a su composición de ácidos grasos, el aceite de nueces N podría ser más estable frente a la oxidación. El valor biológico de sus proteínas es muy similar, siendo la actividad antioxidante la que marca una gran diferencia en favor de los cultivares endémicos: las muestras N dieron los valores más altos, y las F intermedios. Por ello, las variedades locales de Nerpio podrían tener mayores beneficios para la salud que las variedades comerciales, aunque son necesarios estudios sobre su composición en fitoquímicos

    Phytoremediation Potential of <em>Chrysopogon zizanioides</em> for Toxic Elements in Contaminated Matrices

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    Many researchers have demonstrated the advantages of plants in the phytoremediation of soils and waters contaminated with heavy metals, herbicides, pesticides, leachates, etc. The unique morphological characteristics of Chrysopogon zizanioides, commonly known as vetiver, make it a hyperaccumulator of metals; its roots can store high concentrations of heavy metals such as As, Cd, Cr, Cu, Hg, Ni, Pb, Se, and Zn, and it has thus been successfully used in the field of environmental protection. This chapter presents the importance of vetiver, its characterization, and its potential use as phytoremediation potential for toxic elements in contaminated matrices

    Health-related quality of life and mental health in the medium-term aftermath of the Prestige oil spill in Galiza (Spain): a cross-sectional study

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    <p>Abstract</p> <p>Background</p> <p>In 2002 the oil-tanker <it>Prestige </it>sank off the Galician coast. This study analyzes the effect of this accident on health-related quality of life (HRQoL) and mental health in the affected population.</p> <p>Methods</p> <p>Using random sampling stratified by age and sex, 2700 residents were selected from 7 coastal and 7 inland Galician towns. Two exposure criteria were considered: a) residential exposure, i.e., coast versus interior; and b) individual exposure-unaffected, slightly affected, or seriously affected-according to degree of personal affectation. SF-36, GHQ-28, HADS and GADS questionnaires were used to assess HRQoL and mental health. Association of exposure with suboptimal scores was summarized using adjusted odds ratios (OR) obtained from logistic regression.</p> <p>Results</p> <p>For residential exposure, the SF-36 showed coastal residents as having a lower likelihood of registering suboptimal HRQoL values in physical functioning (OR:0.69; 95%CI:0.54–0.89) and bodily pain (OR:0.74; 95%CI:0.62–0.91), and a higher frequency of suboptimal scores in mental health (OR:1.28; 95%CI:1.02–1.58). None of the dimensions of the other questionnaires displayed statistically significant differences.</p> <p>For individual exposure, no substantial differences were observed, though the SF-36 physical functioning dimension rose (showed better scores) with level of exposure (91.51 unaffected, 93.86 slightly affected, 95.28 seriously affected, p < 0.001).</p> <p>Conclusion</p> <p>Almost one and a half years after the accident, worse HRQoL and mental health levels were not in evidence among subjects exposed to the oil-spill. Nevertheless, some of the scales suggest the possibility of slight impact on the mental health of residents in the affected areas.</p

    Non-motor symptom burden in patients with Parkinson's disease with impulse control disorders and compulsive behaviours : results from the COPPADIS cohort

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    The study was aimed at analysing the frequency of impulse control disorders (ICDs) and compulsive behaviours (CBs) in patients with Parkinson's disease (PD) and in control subjects (CS) as well as the relationship between ICDs/CBs and motor, nonmotor features and dopaminergic treatment in PD patients. Data came from COPPADIS-2015, an observational, descriptive, nationwide (Spain) study. We used the validated Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) for ICD/CB screening. The association between demographic data and ICDs/CBs was analyzed in both groups. In PD, this relationship was evaluated using clinical features and treatment-related data. As result, 613 PD patients (mean age 62.47 ± 9.09 years, 59.87% men) and 179 CS (mean age 60.84 ± 8.33 years, 47.48% men) were included. ICDs and CBs were more frequent in PD (ICDs 12.7% vs. 1.6%, p < 0.001; CBs 7.18% vs. 1.67%, p = 0.01). PD patients had more frequent previous ICDs history, premorbid impulsive personality and antidepressant treatment (p < 0.05) compared with CS. In PD, patients with ICDs/CBs presented younger age at disease onset, more frequent history of previous ICDs and premorbid personality (p < 0.05), as well as higher comorbidity with nonmotor symptoms, including depression and poor quality of life. Treatment with dopamine agonists increased the risk of ICDs/CBs, being dose dependent (p < 0.05). As conclusions, ICDs and CBs were more frequent in patients with PD than in CS. More nonmotor symptoms were present in patients with PD who had ICDs/CBs compared with those without. Dopamine agonists have a prominent effect on ICDs/CBs, which could be influenced by dose

    Advances in estimation by the item sum technique using auxiliary information in complex surveys

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    To collect sensitive data, survey statisticians have designed many strategies to reduce nonresponse rates and social desirability response bias. In recent years, the item count technique (ICT) has gained considerable popularity and credibility as an alternative mode of indirect questioning survey, and several variants of this technique have been proposed as new needs and challenges arise. The item sum technique (IST), which was introduced by Chaudhuri and Christofides (2013) and Trappmann et al. (2014), is one such variant, used to estimate the mean of a sensitive quantitative variable. In this approach, sampled units are asked to respond to a two-list of items containing a sensitive question related to the study variable and various innocuous, nonsensitive, questions. To the best of our knowledge, very few theoretical and applied papers have addressed the IST. In this article, therefore, we present certain methodological advances as a contribution to appraising the use of the IST in real-world surveys. In particular, we employ a generic sampling design to examine the problem of how to improve the estimates of the sensitive mean when auxiliary information on the population under study is available and is used at the design and estimation stages. A Horvitz-Thompson type estimator and a calibration type estimator are proposed and their efficiency is evaluated by means of an extensive simulation study. Using simulation experiments, we show that estimates obtained by the IST are nearly equivalent to those obtained using “true data” and that in general they outperform the estimates provided by a competitive randomized response method. Moreover, the variance estimation may be considered satisfactory. These results open up new perspectives for academics, researchers and survey practitioners, and could justify the use of the IST as a valid alternative to traditional direct questioning survey modes.Ministerio de Economía y Competitividad of SpainMinisterio de Educacion, Cultura y Deporteproject PRIN-SURWE
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