Xoconostle fruit (Opuntia matudae Scheinvar cv. Rosa) by-products as potential functional ingredients

There is a lack of information on the potential use of xoconostle cultivars as sources of antioxidants for food, pharmaceutical and colorant industries. The aim of this study was to provide a phytochemical characterisation and antioxidant activity evaluation of Opuntia matudae Scheinvar cv. Rosa by-products (epicarp and endocarp mucilage's), in order to evaluate their interest as sources of functional ingredients for human or animal foods. These by-products showed a high content in glucose, citric and linoleic acids, tocopherols, and isorhamnetin-O-(di-deoxyhexosyl-hexoside) (mainly in epicarp), and presented relevant antioxidant properties. The obtained results support the use of O. matudae Scheinvar cv. Rosa agro-industrial by-products as functional food ingredients, namely for antioxidant-enriched formulations, instead of being discarded.The authors are grateful to the Foundation for Science and Technology (Portugal) for financial support to CIMO (strategic project Pest-OE/AGR/UI0690/2011) and to L. Barros (researcher contract under “Programa Compromisso com Ciência-2008”). The authors also acknowledge the support of Mexican association CoMenTuna for providing the plant materials

An optimized tuned mass damper/harvester device

Much work has been conducted on vibration absorbers, such as tuned mass dampers (TMD), where significant energy is extracted from a structure. Traditionally, this energy is dissipated through the devices as heat. In this paper, the concept of recovering some of this energy electrically and reuse it for structural control or health monitoring is investigated. The energy-dissipating damper of a TMD is replaced with an electromagnetic device in order to transform mechanical vibration into electrical energy. That gives the possibility of controlled damping force whilst generating useful electrical energy. Both analytical and experimental results from an adaptive and a semi-active tuned mass damper/harvester are presented. The obtained results suggest that sufficient energy might be harvested for the device to tune itself to optimise vibration suppression

Exclusive Group Lasso for Structured Variable Selection

A structured variable selection problem is considered in which the covariates, divided into predefined groups, activate according to sparse patterns with few nonzero entries per group. Capitalizing on the concept of atomic norm, a composite norm can be properly designed to promote such exclusive group sparsity patterns. The resulting norm lends itself to efficient and flexible regularized optimization algorithms for support recovery, like the proximal algorithm. Moreover, an active set algorithm is proposed that builds the solution by successively including structure atoms into the estimated support. It is also shown that such an algorithm can be tailored to match more rigid structures than plain exclusive group sparsity. Asymptotic consistency analysis (with both the number of parameters as well as the number of groups growing with the observation size) establishes the effectiveness of the proposed solution in terms of signed support recovery under conventional assumptions. Finally, a set of numerical simulations further corroborates the results.Comment: 36 pages, 2 figures. Not submitted for publication. New licens

Anthocyanin Copigmentation: Evaluation, Mechanisms and Implications for the Colour of Red Wines

[EN]Copigmentation is the main colour-stabilizing mechanism in plants and in food products of vegetable origin. It is a spontaneous and exothermic process that consists of the stacking of an organic molecule, called copigment, on the planar polarizable moieties of the anthocyanin coloured forms. Although this phenomenon has long been described, there are some aspects that are still not well understood or controversial like the nature of the interaction pigment to copigment, the way to quantify the extent of the process, its effect on other anthocyanin properties like astringency or reactivity. In this article a review of the most significant advances achieved in the last years in the field of intramolecular and intermolecular copigmentation is presented. Also, the most recent findings regarding wine copigments and their effects on the colour of red wines are revised

Determination of suitable irrigation lengths and intervals using capacitance humidity sensors for a sandy soil

production, during the summer of 2010. This farm is integrated at the Spanish research network for the sugar beet development (AIMCRA) which regarding irrigation, focuses on maximizing water saving and cost reduction. According to AIMCRA 0 s perspective for promoting irrigation best practices, it is essential to understand soil response to irrigation i.e. maximum irrigation length for each soil infiltration capacity. The Use of Humidity Sensors provides foundations to address soil 0 s behavior at the irrigation events and, therefore, to establish the boundaries regarding irrigation length and irrigation interval. In order to understand to what extent farmer 0 s performance at Tordesillas farm could have been potentially improved, this study aims to address suitable irrigation length and intervals for the given soil properties and evapotranspiration rates. In this sense, several humidity sensors were installed: (1) A Frequency Domain Reflectometry (FDR) EnviroScan Probe taking readings at 10, 20, 40 and 60cm depth and (2) different Time Domain Reflectometry (TDR) Echo 2 and Cr200 probes buried in a 50cm x 30cm x 50cm pit and placed along the walls at 10, 20, 30 and 40 cm depth. Moreover, in order to define soil properties, a textural analysis at the Tordesillas Farm was conducted. Also, data from the Tordesillas meteorological station was utilized

Simptomatologia depressiva, estrès percebut i suport social en adolescents víctimes de ciberassetjament

Els estudis suggereixen que el ciberassetjament escolar comporta conseqüències greus en l'àmbit psicosocial per a les cibervíctimes, a més les en l'ajust psicològic (depressió i estrès percebut) i social (percepció de suport social formal i informal) entre adolescents víctimes i no víctimes d'assetjament mitjançant les Noves Tecnologies de la Informació (TIC). La mostra va estar formada per 590 adolescents d'ambdós sexes i d'edats compreses entre els 11 i els 18 anys, els quals van omplir per als objectius del present estudi les escales de: victimització a través del telèfon mòbil i a través d'Internet; depressió; estrès percebut; i suport social comunitari. Els resultats han indicat que les víctimes de ciberassetjament escolar tenen puntuacions superiors en simptomatologia depressiva, estrès percebut, i puntuacions inferiors en la percepció de suport social dels sistemes formals, en comparació dels adolescents no victimitzats, i no hi ha diferències significatives entre els grups en la percepció de suport social dels sistemes informals. Es discuteixen aquests resultats i les implicacions per a investigacions futures. víctimes no confien que els adults i les autoritats siguen capaços d'ajudar-los. Per això, l'objectiu principal d'aquest treball fou analitzar si hi ha diferèncie

Análisis de fluctuación térmica y perspectivas en vestimenta inteligente

La monitorización de parámetros biológicos es cada día más empleada en el ámbito médico, deportivo (atletismo, ciclismo, montañismo) y profesional. En este trabajo presentamos un estudio realizado, empleando tarjetas de adquisición de temperatura TURBOTAG, que almacenan hasta 700 datos que se pueden trasferir al PC a través de un lector RF. Estas tarjetas se facilitaron a 15 alumnos de doctorado y las mantuvieron pegadas a la piel o en el bolsillo de alguna de sus prendas, durante 3 días. Tras analizar los datos obtenidos, se puede observar que la temperatura tiene oscilaciones ocasionadas por los cambios externos de temperatura, pero en ocasiones esas fluctuaciones pueden producirse por variaciones anómalas de la temperatura corporal. El concepto de traje inteligente surge ante la posibilidad de englobar la sensórica apropiada y la tecnología capaz de procesar la señal, acondicionarla y almacenarla o transmitirla de forma inalámbrica a un PC o una PDA, y además emplear nuevos textiles especialmente diseñados

Modal stability of inclined cables subjected to vertical support excitation

In this paper the out-of-plane dynamic stability of inclined cables subjected to in-plane vertical support excitation is investigated. We compute stability boundaries for the out-of-plane modes using rescaling and averaging methods. Our study focuses on the 2:1 internal resonance phenomenon between modes that occurs when the excitation frequency is twice the first out-of-plane natural frequency of the cable. The second in-plane mode is excited directly, while the out-of-plane modes can be excited parametrically. An analytical model is developed in order to study the stability regions in parameter space. In this model we include nonlinear coupling effects with other modes, which have thus far been omitted from previous models of parametric excitation of inclined cables. Our study reflects the importance of such effects. Unstable parameter regions are defined for the selected cable configuration. The validity of the proposed stability model was tested experimentally using a small-scale cable actuator rig. A comparison between experimental and analytical results is presented in which very good agreement with model predictions was obtained. r 2008 Elsevier Ltd. All rights reserved