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The effective re-use of industrial by-products calls for an understanding of their chemical, mineralogical and physical characteristics. The by-product used in this study was coated paper industry sludge from a plant whose sole prime material is recycled paper. Due to its high organic and calcium carbonate content and the presence of several clayey materials such as talc and kaolinite, incineration conditions had a significant effect on the mineralogy of such sludge. The present study examined the impact of such conditions on the pozzolanic properties of coated paper sludge. Several temperature intervals ranging from 600 to 750 ºC were studied to determine the conditions yielding the most promising pozzolanic properties.

The present article discusses the effect of paper sludge additions, calcined at 700 ºC for two hours, on cement paste pore structure and mechanical strength. Both total and capillary porosity were observed to depend on the percentage of calcined sludge added to the cementitious matrix. While a 10% addition induced values for both slightly higher than the control, adding 20% prompted the opposite result, reducing porosity values with respect to the control. Substantial refinement was observed, with a rise in pores smaller than 0.01 μm (gel pores) when the calcined sludge was added. Such refinement was greater at the higher percentage of sludge. After approximately 15 days, strength was lower in both the additioned pastes compared to the control. A high correlation (R2≥0.939) was found between total porosity and compressive strength for both percentages studied.

Mineralogically, the paper mill sludge consists essentially of calcite, kaolinite, talc and other philosilicates (illite, chlorite). When such sludge is subjected to controlled thermal treatment, its kaolinite component may be transformed into metakaolin, yielding a product with high pozzolanic reactivity. This study was designed to analyze a number of scientific questions around the production of pozzolanic additions via controlled thermal activation of paper mill sludge and to evaluate the performance of such additions when included in a cement matrix. The findings show that paper mill waste activation is optimal when the sludge is calcined for 2 hours at 700 ºC in the 700-800 ºC interval. A comparative study between the cement made with the new addition and a commercial cement (CEM I-42.5R) used as a reference led to highlight the scientific and technical viability of this waste as a cementing secondary material.

The present study addresses variations in the calcination temperature (600-750 ºC) and kiln time (two to five hours) applied to activate coated paper waste and their effect on the rheological, physical and mechanical behaviour of cement matrices containing these active additions. The results obtained showed that the conditions under which kaolinite was activated had a direct effect on the subsequent behaviour of the calcined products. At activating temperatures of over 700 ºC, pozzolanic activity and mechanical strength were observed to be lower, setting time shorter and the mortar less workable.

El artículo analiza la mención de un dibujo a pluma atribuido a Van Eyck en un inventario post-mortem fechado en 1452, y realizado en Valencia. Los bienes del elenco pertenecieron a Andreu Garcia, presbítero beneficiado en la catedral de la ciudad bien conocido por la historiografía en virtud de sus importantes vínculos con los artistas más señalados que trabajaron en la urbe durante la primera mitad del siglo XV. La noticia da pie a una nueva revisión del cada vez más improbable paso de Van Eyck por los territorios de la Corona de Aragón, así como de la huella temprana de su pintura en estos lugares, habida cuenta de que, como revela el documento, el primer propietario del dibujo fue Berenguer Mateu, pintor hermano de Jaume Mateu, uno de los mejores representantes de la segunda generación de pintores del Gótico Internacional en la capital del Reino.

Los temas griegos en -ōs/-eu, -ēs/-eu, -ā/ei deben interpretarse como derivados de antiguos temas indoeuropeos en laringal.

Tomando como fuente de información para esta comunicación el Repertorio EUROSPES de Bases de Datos en Ciencias Sociales editado en 1990, se analiza la oferta de Información a través de las Bases de Datos creadas en los países europeos de habla latina. El objetivo del trabajo que se presenta es conocer, de manera detallada, los rasgos que definen esta oferta en cada país y en el conjunto de países estudiados. Estructurado en dos partes, en la primera se ofrecen, en primer lugar, datos sobre las características de la información contenida en las bases de datos: naturaleza de la información, temas sobre los que versa, cobertura temporal, técnicas documentales utilizadas, normas de descripción bibliográfica, productores de esas Bases de Datos. En segundo lugar, se estudian los aspectos relativos a la distribución de la información: distribuidores, -paquetes de gestión de bases de datos, instrumentos de ayuda al usuario para las consultas, tipo de acceso que se ofrece. La segunda parte se dedica al análisis de los datos aportados en la primera: distribución de la producción de bases de datos por temas, países y años, estudio de las áreas temáticas no cubiertas, comparación de las técnicas documentales empleadas, compatibilidad de los paquetes de gestión y de los formatos informáticos, análisis de la calidad de los servicios de acceso, precios, formación ofrecida, etc. Se finaliza con unas conclusiones orientadas a proponer los desarrollos deseables para el conjunto de paises así como las posibilidades de cooperación con vistas a mejorar la oferta de información automatizada en Ciencias Sociales.

In the course of the process of elaboration of virgin olive oil (whose main stages are crushing, malaxation and centrifugation) the transfer of several minor components to the triacylglycerol constituent of the oily globules originally present in the cells of the fruit mesocarp is produced. Such minor components are chemical species present in the olive fruits, as well as those resulting from chemical or enzymatic processes which take place in the olive paste upon crushing. In this paper several types of transferable minor components, as well as those parameters affecting the rates of transfer are studied.Geometric and physical variations of interfacial regions between the oil and other systems in contact with it are discussed. These systems are olive vegetation water, olive pulp components, and fragments of the woody endocarp, as well as the atmospheric air and the tools and equipment of the oil mill. This article concludes with some considerations about the improvements of virgin olive oils achieved by controlling the transfer of minor components.

Aldehydic acids are generated in oxidized lipids as a result of decomposition of hydroperoxides by (β-scission reactions. Aldehydes are known to interact with proteins and DNA and to impair enzymatic functions. Aldehydic esters from oxidized lipids were reabsorbed to a significant extent in rats. This paper reviews the mechanism of formation of esterified aldehydic acids in frying oils and their physiological/toxicological effects. The paper also gives an overview of relevant basic analytical techniques that needs to be improved to establish reliable quantitative method (s).

Internet provide access to a huge of scientific and technical information on Internet which is not validated by any committee of experts. This information needs filtering in order to optimize user access to these resources. In this paper, we describe the development of a WEB page outlining the activity of our research team Food Lipids Quality and Health. The WEB page seeks to fulfil the following objectives: to communicate the activities of the team, to use effectively the resources that Internet offers and to promote their use among the team. We report on the methods used in achieving these objectives. Finally, a large number of WEB addresses related to Lipids are presented and classified. The addresses have been selected on the basis of their usefulness and interest value.

This paper deals with antioxidant activity of sterols and natural organic acids not covered on previous papers. The paper «Antioxidant activity of phenolic compounds» covered phenolic acids; the second one «Antioxidant activity of vitamin C, D and provitamin A», ascorbic acid, and the third «Antioxidant activity of natural nitrogenous compounds», aminoacids. The acids studied here included citric, malic, lactic, fumarle, tartaric, kojic (5-hydroxy-2-[hydroxymethyl-γ-pyrone], phytic (inositol-hexaphosphoric acid) and furoic acids. The reaction mechanisms, either as inhibitors of the chain reaction of prooxidant radicals or by sequestration of free radicals was discussed. Finally, a list of recent patents of these compounds and their derivatives as antioxidants or synergists was included.

The conjugated linoleic acid (CLA) is a term referred to a mixture of positional and geometrical isomers of linoleic acid with double conjugated bonds in carbon atoms 10 and 12 or 9 and 11 with all of the possible cis and trans combinations. CLA is a naturally occurring substance in food. The major dietary sources of CLA are foods derived from ruminants, e.g. beef and cheese and its content increases when meals are processed. There is ample evidence showing that free radicals and oxidation processes mediated by free radicals play an important role in many pathological situations including cancer and atherosclerosis. Natural and synthetic antioxidants, tolerated by humans, are employed in order to avoid or treat these pathologies. In the present paper, articles evaluating the antioxidant or prooxidant activity of CLA have been revised. Preliminary in vivo and in vitro studies suggested the antioxidant role for CLA, however recent researches have not shown any evidence related to it. New studies have to be carried out in order to get more information on the antioxidant and protective role of CLA in free radical-related degenerative diseases.

The extraction of pesticides from fatty samples is a problem extensively studied. In this paper, the main techniques for the extraction of pesticides from fatty samples are reviewed. In this extraction, the extraction of fat material is a fact that is difficult to avoid, so it’s necessary to apply clean-up systems prior to subsequent steps in the analytical process. The clean-up techniques are reviewed too.

Several studies have reported that fatty acids act as modulatory agents of immune response of experimental animals and humans. In this paper, we do and overview of the performed studies by using of unsaturated fatty acids and their influence on several immunitary parameters in studies carried out in vitro as well as ex vivo. It has been shown that unsaturated fatty acids are involved in the reduction of lymphocyte proliferation, cytokine production and natural killer cell activity. On the other hand, in this article we have reviewed the mechanisms by which fatty acids modulate the immune response: I) membrane fluidity alteration; II) production of lipid peroxides; III) eicosanoid production; IV) gene expression modulation.

The paper comments the different regulations related to table olives at national or international scales. The Unified Qualitative standard Applying to Table Olives in International Trade and COI/Codex (International Olive Oil Council, IOC, and IOC/Codex Alimentarius), «Reglamentación Técnico Sanitaria para la elaboración, circulación y venta de aceitunas de mesa» (Spanish), «Normas de calidad para la exportación de aceitunas de mesa» (Spanish), and the United States Standards for Grades of Green and Canned Ripe Olives (USA) are especially considered. The effects of the new regulations on Nutritional Labelling (mainly in USA), applications of the Analysis and Control of Critical Points (ACCP), and the problems derived from the application of the ISO 9000, or EN 29000, to this Sector are also discussed.

The paper comments, beginning with the systems and technologies developed in the 70*'' to reduce the production cost and improve the final product quality to arrive to the current processes, machinery and equipments. The content is divided in three parts: olive growing, processes and waste waters.

Este trabajo tiene por objetivo determinar la posible correlación existente entre la producción científica española cubierta por las 100 revistas SCI con mayores factores de impacto y la presencia de investigadores españoles en los consejos o comités científicos de dichas revistas. El análisis de la composición de los consejos editoriales ha permitido constatar que la adscripción de instituciones científicas europeas en los comités o consejos editoriales de las 100 primeras revistas del JCR es muy reducida, estando estos órganos mayoritariamente constituidos por investigadores norteamericanos y británicos. La presencia de miembros de instituciones científicas españolas en los comités editoriales es significativamente escasa, tanto desde una perspectiva mundial como a escala europea. De los 3.474 miembros identificados, únicamente 16 son investigadores españoles y participan en los comités de 9 revistas. Por otra parte, estas 9 revistas, no muestran unas cifras de producción científica española mayores que las correspondientes a países con notables semejanzas científicas con España, como Italia u Holanda. Estos indicadores pretenden servir de base para el debate y la posible implementación de medidas para incrementar la presencia española en comités editoriales de las principales revistas científicas de proyección internacional.

In this paper the effects of the enzymatic treatment on the quality and composition of vegetable edible oils are revised. Stability and refinability related aspects of oils from seeds, olive and other fruits are presented, so as an organoleptic valoration of the olive oil. Oils from enzyme aided processes show composition and characteristics similar to the ones from oils obtained from raw materials.

The paper reviews the characteristics for the lactic acid bacteria (LAB) growth in the three main table olive types in the international trade. The only typical spontaneous lactic process is that followed in the Spanish-style green olives. The growth of LAB throughout storage in brine of ripe olives and fermentation of naturally ripe (black) olives depends on various factors such as olive cultivars, sodium chloride concentration, initial pH correction, etc. The knowledge of the spontaneous growth conditions is essential for a better microbiological control and the efficient use of starter cultures in these fermentations.

The paper reviews the world production of cotton and the use of pesticides in its growth. The risks derived from their abuse, especially chlorinated ones, are commented. Organophosphorous pesticides and carbamates have a wider spectrum of activity and less environmental persistence, although their are more toxic for mammalian beings. Since the 70th, the «piretrinas» have solved some of the problems derived from pets with resistance to the above mentioned two pesticides. Nevertheless, utilization of pesticides in this culture should be diminished since their use is not efficient nowadays and even in some cases there is a production decrease. On the other hand, consumers are progressively demanding the so called «ecological products». Thus, EU countries should be more restrictive with respect to the pesticides tolerances in cotton to be able to use the «Ecological label» of the European Union.

The present paper focusses on the fatty acid hydroperoxides pathways, mainly hydroperoxide lyase and hydroperoxide dehydrase. For each enzyme, the definition, occurrence and subcellular localization is presented. Particular attention is given to reaction mecanisms and to substrate specificity. Physiological roles of reaction products are also discussed.

The paper is a review of the soja oil extraction and soja flour obtention (raw material control as well as equipments and know for conditioning, extraction, and desolventization). It also includes comments related to current research lines.

The paper shows current overview and the perspectives related to the production of oilseeds, fats and oils as well as the consumption of them. The study is based on the evolution of several variables such as changes in population, policies, incomes, prices, availability of natural resources (land for agriculture) and environmental impact. With respect to technology, the work comments the possible influences of biotechnology transportation systems, milling, and some transformations for specific uses. Among the promising uses of vegetable oils the following are mentioned: utilization as biodiesel, adhesives, biodegradable plastics, printing inks, lubricating oils, hydraulic fluids or, even, new tendencies in the area of nutrition (foods with pharmacological effects).

The paper comments the most adequate conditions required to produce to quality soybean oil. It is essential to avoid contaminations (water, metallic, oxidation products), overheating, undue exposition to air, as well as an appropriate control of the different steps of the refining process.

The paper comments different formulations of soy oil products such as salad and cooking oils, margarine, shortenings, commercial shortenings, frying shortenings, and fluid shortenings. Hydrogenation and its influence on final products is also included.

This paper deal with the main aspects of the analysis of oxysterols. This analytical problem is quite new and many questions involved are still controversial. Consequently, many methodologies exist that still need improvement and standarization. Therefore, it is interesting to discuss the analytical methodologies proposed by different authors for the extraction, purification and determination (gas chromatography and high performance liquid chromatography) of oxysterols.

As a continuation of the study of natural antioxidants, this paper includes vitamin C (ascorbic acid), vitamin E (tocopherols and tocotrienols), and provitamin A (β-carotene, lutein, zeaxanthin, isozeaxanthin, lycopene, astaxanthin and cantaxanthin) and, as well as those derivatives of these which have been described as antioxidants, either used as food additives or protectans of cell membranes (in vivo). Their role as inhibitors of chain reactions of prooxidant radicals by irreversible reaction or quenching of such radicals is discussed. Finally, patents registered during the last years for these compounds, their derivatives and synergists are cited.

A review on the obtention of plant protein hydrolysates for food use has been carried out. First, the components and factors that participate in the hydrolysis are described. Then a description of the different types of hydrolysates is done: limited hydrolysates (between 1% and 10% degree of hydrolysis) that are used to improve functional properties of foods; hydrolysates with variable degree of hydrolysis that are used as flavourings; by last, extensive hydrolysates (degree of hydrolysis above 10%) that are used as protein suplement in the diet or with a defined composition for the treatment of specific illness.

Neutral energy and macronutrient balances are needed for the maintenance of a stable body weight. High-fat diets promote fat accumulation. This fact is not only due to the induction of a caloric hyperphagia, but also to the failure to adjust fat oxidation in response to an excess of fat intake. This situation does not occur with carbohydrates. In addition, the fatty acid composition of dietary fat can also be an important factor determining the resulting level of body weight and body energy stores. The modifications induced in adipocyte membrane fatty acid composition and in stored triglycerides lead to changes in the efficiency of the lipid mobilization. On the other hand, the activity of lipoprotein-lipase and lipogenic enzymes can be modulated by some fatty acids. The fate of the different fatty acids is not the same. Some of them are preferentially oxidized, others are stored and others play a structural role. Finally, diet-induced thermogenesis is increased by certain fatty acids and that contributes to an increased energy expenditure.

A review on the bioactive peptides described so far in storage proteins, mainly milk proteins, has been carried out. Bioactive peptides are small amino acid sequences inactives in the native protein, but that can be liberated after hydrolysis of these proteins and exert different functions. Among the main one are bioactive peptides with opioid activity, antagonistic opioid, immunomodulatory, antithrombotic, ion transporting or antihypertensive. The possible presence of these peptides in other protein source, mainly oilseed plants and their possible use is discussed.

In this paper the role of peroxidases in the last step of the ethylene biosynthesis pathway, the conversion of 1-aminocyclopropane- 1-carboxylic acid, is discussed.

Triglycerides are at the same time, one of the most abundant and complex lipid fraction in the nature. For this reason, it is esential to determine their molecular species composition, as well as to know the stereospecific position in which the fatty acids are located, in order to characterize animal fats and vegetable oils. The most commonly employed technique for this objective is high-performance liquid chromatography, in general using reversed phase columns. In the present article we describe the operative conditions employed nowadays in order to achieve the optimum resolution for the triglyceride chromatographic peaks, and also the present situation of the knowledge in the separation of the molecular species of complex mixtures of triglycerides, such as milk fat, fish oil and hepatic fat, which are of importance in the industrial sector and human nutrition.