A study of the antioxidant capacity of oak wood used in wine ageing and the correlation with polyphenol composition

The antioxidant capacity of oak wood used in the ageing of wine was studied by four different methods: measurement of scavenging capacity against a given radical (ABTS, DPPH), oxygen radical absorbance capacity (ORAC) and the ferric reducing antioxidant power (FRAP). Although, the four methods tested gave comparable results for the antioxidant capacity measured in oak wood extracts, the ORAC method gave results with some differences from the other methods. Non-toasted oak wood samples displayed more antioxidant power than toasted ones due to differences in the polyphenol compositon. A correlation analysis revealed that ellagitannins were the compounds mainly responsible for the antioxidant capacity of oak wood. Some phenolic acids, mainly gallic acid, also showed a significant correlation with antioxidant capacity

Efficient symbolic computation of approximated small-signal characteristics of analog integrated circuits

A symbolic analysis tool is presented that generates simplified symbolic expressions for the small-signal characteristics of large analog integrated circuits. The expressions are approximated while they are computed, so that only those terms are generated which remain in the final expression. This principle causes drastic savings in CPU time and memory, compared with previous symbolic analysis tools. In this way, the maximum size of circuits that can be analyzed, is largely increased. By taking into account a range for the value of a circuit parameter rather than one single number, the generated expressions are also more generally valid. Mismatch handling is explicitly taken into account in the algorithm. The capabilities of the new tool are illustrated with several experimental result

A Family of matroid intersection algorithms for the computation of approximated symbolic network functions

In recent years, the technique of simplification during generation has turned out to be very promising for the efficient computation of approximate symbolic network functions for large transistor circuits. In this paper it is shown how symbolic network functions can be simplified during their generation with any well-known symbolic network analysis method. The underlying algorithm for the different techniques is always a matroid intersection algorithm. It is shown that the most efficient technique is the two-graph method. An implementation of the simplification during generation technique with the two-graph method illustrates its benefits for the symbolic analysis of large analog circuits

Algorithm for efficient symbolic analysis of large analogue circuits

An algorithm is presented that generates simplified symbolic expressions for the small-signal characteristics of large analogue circuits. The expressions are approximated while they are computed, so that only the most significant terms are generated which remain in the final expression. This principle leads to dramatic savings in CPU time and memory compared to existing techniques, significantly increasing the maximum size of circuits that can be analysed. By taking into account a range for the value of a circuit parameter rather than one single number the generated symbolic expressions are also generally valid

Symbolic analysis of large analog integrated circuits by approximation during expression generation

A novel algorithm is presented that generates approximate symbolic expressions for small-signal characteristics of large analog integrated circuits. The method is based upon the approximation of an expression while it is being computed. The CPU time and memory requirements are reduced drastically with regard to previous approaches, as only those terms are calculated which will remain in the final expression. As a consequence, the maximum circuit size amenable to symbolic analysis has largely increased. The simplification procedure explicitly takes into account variation ranges of the symbolic parameters to avoid inaccuracies of conventional approaches which use a single value. The new approach is also able to take into account mismatches between the symbolic parameters

Towards the characterization of individual users through Web analytics

We perform an analysis of the way individual users navigate in the Web. We focus primarily in the temporal patterns of they return to a given page. The return probability as a function of time as well as the distribution of time intervals between consecutive visits are measured and found to be independent of the level of activity of single users. The results indicate a rich variety of individual behaviors and seem to preclude the possibility of defining a characteristic frequency for each user in his/her visits to a single site.Comment: 8 pages, 4 figures. To appear in Proceeding of Complex'0

Social factors associated with the effectiveness of a Spanish parent training program-An opportunity to reduce health inequality gap in families

Parent training programs (PTPs) have been used extensively in Anglo-Saxon countries, but less so in Southern Europe. Several characteristics of families have been linked to effective parenting and positive development of children, but few studies have examined the social determinants of the effectiveness of PTPs. The Parenting Skills Program for families (PSP) is a PTP from Spain. This study aimed to identify the social characteristics (sex, age, country of birth, marital status, educational level, and employment status) of parents that determine the success of the PSP in relation to social support, parenting skills, parental stress, and negative behaviors among children. A quasi-experimental study with a prepost design with no control group was used. We conducted a survey before (T0) and after the intervention (T1). Sample size was 216. We fit multiple logistic regression models. Parenting skills increased more among parents with a lower educational level. Parents' stress decreased more among parents who had a lower educational level, were unemployed, and were men. Social support increased among parents who were younger, unemployed, or non-cohabiting. We found no significant differences in the effect on children's negative behaviors according to the social factors evaluated. The PSP is effective for socioeconomically diverse families, but the success differs according to the parents' social profile. Unlike most previous studies, the results were better among more socially disadvantaged people, highlighting the potential of this kind of intervention for reducing the social inequality gap between groups

Caracterización preliminar de emisiones de gases de efecto invernadero (CH4 y CO2) procedentes de volcanes de fango del Golfo de Cádiz

Mud volcanism represents an important migration pathway for methane and other gases from deeper reservoirs to the surface; however most submarine sources remain poor quantified. During SUBVENT2 cruise, water column over several mud volcanoes were surveyed for gas seepage characterization. Water samples of ROV Niskin and Rosette-CTD Niskin bottles were recovered above the Bonjardim, El Cid, Las Negras, Mercator, Algacel, Mvseis, Madrid and Yuma mud volcanoes, and at three newly discovered, mud volcano like structures, to quantify overall gases release fluxes from seabed. CO2 and CH4 concentrations were measured by potentiometric titration and using a gas chromatograph, respectively, in order to understand the relationship between physicochemical and geological processes. Gases concentrations decreased from shallower to deeper mud volcanoes. Values varied widely within 50 to 200 nM for CH4 and between 400 to 1500 μatm for fCO2. Greenhouse gases variations were large influenced by water column depth, temperature, salinity and possibly by anaerobic oxidation of methane (AOM). Our observations suggest that the emission of methane and carbon dioxide from the mud volcanoes structures studied here may be relevant at the present as a part of the carbon global cycle.Versión del edito

Infaunal macrobenthos in the Porcupine Bank (NE Atlantic)

The results of the macroinfaunal communities distributions from the annual series surveys PORCUPINE are shown. Those surveys were realized during the months of September and October in the years 2006, 2008, 2009, 2010, 2011, 2012 and 2013 by the Instituto Español de Oceanografía aboard the R /V Vizconde de Eza, within the research project ERDEM. This survey series has as main objective the obtainment of abundance indexes of the benthonic and demersal fauna from Porcupine Bank, west of Ireland, with special attention on the commercial species exploited by the Spanish fleet (hake, angler fish, megrim and norwegian lobster). For the study of the infaunal macrobenthos a total of 50 samples were analyzed from selected places of the Bank, where the bottom characteristics, the climatology or the survey schedule allowed. Samples were taken with an ULSNER box corer with 0.09 m2 of sampling area. Samples for the faunal study were sieved aboard with a 0.5 mm mesh size sieve. The material collected in the sieve was preserved with 8 % formaldehyde neutralized with borax, and stained with Rose Bengal solution for the posterior sorting and identification of fauna. Additional samples were taken to estimate the organic content of the sediment and to perform the granulometric analyses. Once in the laboratory, the granulometry was analyzed following the method recommended by Buchanan (1984); which consists in a combination of dry sieving of the coarse fraction (> 62 µm) and the sedimentation at 20 ºC of the fine fraction (< 62 µm) in a distilled water column. Sediment organic matter content was calculated as the percentage of weight loss by means of 24 hours sample calcination at 500 ºC, after dried it at 100 ºC during the same time. Complementary, in order to obtain a better coverage of the sedimentary types from the study area, more than 350 samples were collected with a net collector coupled to the trawling fishing gear (Baca-GAV 39/52). Globally, the sediments of the majority of the sampled stations are mainly formed by sand, between fine and very fine, except in deep areas of the southeast, where there are large muddy areas with elevated organic content and high selection coefficient. In the north, around the shallowest area, we found thicker sandy sediments, with lower organic content and moderate selection. The macroinfaunal communities from the Porcupine Bank are characterized by the dominance of the faunistic group of polychaetes (68.8 %), mainly represented by the families Owenidae, Spionidae, Paraonidae and Sabellidae. The next in number are the group of molluscs (17.6 %), dominated by the family Kelliellidae, which reaches maximum abundances up to 7520 ind•m-2. The poorest represented groups are the crustaceans (5.0 %), echinoderms (4.3 %) and the “others” (sipunculids, nemertine, etc.), being the latter the least abundant (3.7 %). In relation with the spatial distribution four macroinfaunal groups were indentified in the Porcupine Bank: - Group 1: located in intermediate depth areas, over sandy sediments with low organic content. The infaunal community is dominated by polychaetes from the Owenidae family, mainly represented by the specie Galathowenia oculata. - Group 2: occupies the sandy and low organic content sediments from the shallowest area of the Bank. Polychaetes are the most representative faunistic group, highlighting the dominance of the families Spionidae and Paraonidae. Prionospio fallax and Aricidea wassi are the most representative species of the group. - Group 3: situated in two deep areas in the south area of the Bank with muddy and high organic matter content sediments. It has the lowest infaunal abundance of the study, being dominated by the bivalve molluscs from the family Kelliellidae and by the annelids polychaetes from the family Paraonidae. - Group 4: Is the cluster that includes more stations in throughout the study. It is distributed spatially in the south area of the Bank, in different bathymetries, with the most heterogeneous sediments and moderate organic content. The bivalve molluscs from the Kelliellidae family again become dominant, with Kelliella miliaris reaching abundance over 7500 ind•m-2.IE