Ricardo Lopez

The purpose of this work, performed in 2009, was to study the effect of temperature and relative humidity on the germination of Bremia lactucae Regel sporangia. The effect of these variables on the in vitro germination of sporangia was evaluated in incubation chambers, with 21 treatments formed by the temperature levels of 5, 10, 15, 20, 25, 30, 35 ºC combined with humidities of 70, 80, 90%. Germination was evaluated 24 h after the treatment was established. A statistical analysis was carried out to determine the importance of these variables and their interaction on the germination of sporangia and infer on the optimum temperature and humidity ranges. We found that there is a significant effect of the interaction between these variables on germination, which appears starting at 5 ºC until 25 ºC. The treatment that presented the highest percentage of germination was 10 ºC, in combination with a relative humidity of 90%. Based on an surface response analysis, we concluded that the op...

Pre-fermentation heat treatment or thermovinification is becoming more widespread in France to produce red wines with fruity characteristics. Results obtained in the framework of the VINAROMAS European project (POCTEFA 2007-2013) suggest thermal degradation of several grape-derived aroma compounds in comparison to a standard vinification, when grapes are heated during three hours at a temperature exceeding 70°C. Following these findings an experiment was launched in 2014 on Spanish Carignan and French Fer grapes in order to study the impact of a pre-fermentation heat treatment of grapes at 50°C on conventional enological parameters, aroma precursors, aroma compounds and polyphenolic composition. Analyses were performed in musts and wines prepared under micro-vinification techniques (1L Erlenmeyer) with two replicates per treatment. Two levels of temperature (75°C and 50°C) and two levels of heating length (30 minutes and 3 hours) were investigated. All the analytical data including ...

The numerical study of transient two-phase flows claims for high order temporal integration schemes. This is relevant when the system is subjected to temporal variations in the boundary conditions that represent physical fluctuations in the inlet conditions. In our case the approximate solution in the pressure drop and true void fraction may vary rapidly, justifying the need of a high order schemes. This work studies the effect of the order of accuracy in the application of the diagonally implicit Runge-Kutta (DIRK) scheme. The input signals considered are constant amplitude and single frequency functions for heat flux boundary conditions.

L’un des volets du projet VINAROMAS a permis de caractériser finement cinq itinéraires de macération en rouge. Certaines de ces techniques, comme la macération préfermentaire à chaud ou la macération carbonique par exemple, ont fait l’objet d’études il y a de nombreuses années. Ces recherches s’étaient alors orientées plus sur l’optimisation du potentiel polyphénolique des vins, que sur les modifications aromatiques induites. Cependant des travaux réalisés dans les années 1980 (Ducruet 1984) font mention de concentrations supérieures en décanoate d’éthyle, en terpénols, en eugénol, en vanillates, en éthyl et vinyl-gaïacol, en éthyl et vinylphénols, en benzaldéhyde et en cinnamate d’éthyle sur les vins issus de macération carbonique. Il a également été démontré que la macération préfermentaire à chaud favorisait la présence de quantités importantes d’esters dans les vins (Girard 1989) tout en dégradant la 3-isobutyl-2-methoxypyrazine (IBMP), responsable des notes de poivron vert (Rou...

Les premiers travaux scientifiques répertoriés sur le traitement thermique de la vendange ont été conduits en laboratoire et de manière artisanale il y a plus de 60 ans en Californie (Berg 1950). Dans les années soixante-dix, le développement de systèmes industriels de chauffage et le nombre important d’articles scientifiques sur le sujet (Poux 1974 ; Humbert and Mignonac 1975) reflètent le fort intérêt de la filière pour cette technologie. Aujourd’hui, les techniques préfermentaires de chauffage de la vendange redeviennent de plus en plus populaires afin d’élaborer des vins fruités adaptés au marché mondial. En 2008, le volume de vin en France élaboré par ces technologies était estimé à 8 millions d’hectolitres (Escudier et al., 2008). Elle consiste à chauffer des raisins entre 70 et 75 °C pendant une période qui peut varier de 30 minutes à 24 heures. Lorsque la durée de chauffage est courte et n’excède pas typiquement une heure, la technique est désignée sous le nom de « thermovin...

Depuis 2004, l’IFV Sud-Ouest étudie l’intérêt de pulvérisations foliaires d’azote réalisées à la véraison afin d’améliorer le fruité des vins issus de cépages dont le potentiel aromatique s’exprime par la présence de thiols variétaux comme le Colombard ou le Sauvignon. La technique, qui a fait l’objet de nombreuses communications ces dernières années (Charrier et Dufourcq 2007, Lacroux et al 2008, Charrier et al. 2009, Dufourcq et al. 2009), a connu un réel essor dans la plupart des vignobles français et particulièrement ceux du Sud-Ouest. Si ce type de fertilisation, parfois couplée à des apports de soufre élémentaire, est également utilisé avec succès sur cépages rouges en vinification en rosé, son adaptabilité pour l’élaboration de vins rouges continue de soulever certaines interrogations. En favorisant l’apparition de tenaces notes de réduction en cours de fermentation, l’association azote/soufre qui permet d’enrichir les teneurs en 3-mercaptohexanol (Dufourcq et al. 2009), est ...

In this paper we will explore the various ways in which Computer Vision techniques can aid and sometimes even replace the classical algorithms used in many still image and video coding standards. Because compression factor is one of the most important performance criteria of image/video coding we will examine the effectiveness of these techniques in achieving low and very-low bit

Experiments were carried out on Grenache, Carignan and Fer grapes in order to characterize the changes in nitrogen content of the musts, conventional enological parameters and aroma compounds of the wines induced by pre-fermentation heating of the grapes followed by alcoholic fermentation in liquid phase or in solid phase. In comparison to a standard vinification, we showed that a two-hour heat treatment at 70°C induced a significant loss in several grape-derived aroma compounds (terpenols, norisoprenoids and some phenols) associated with an increase in α-terpineol, guaiacol and 2,6-dimethoxyphenol, which suggests thermal degradation. A significant increase in most of the ethyl esters, in acetates and in fatty acids were observed in wines fermented in liquid phase, together with a decrease in fusel alcohols. The substantial modification in the amino acid composition of the must seems to be a crucial element for the understanding of these changes.

Five young monovarietal white wines from the Canary Islands made from Gual, Verdello, Marmajuelo, white Listán, and Malvasia grape cultivars were studied to determine the characteristics of their most important aromas and the differences among them. The study was carried out using gas chromatography-olfactometry (GC-O) to detect the potentially most important aroma compounds, which were then analyzed quantitatively by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The strongest odorants in the GC-O experiments were similar in all cases, although significant differences in intensity between samples were noted. Calculation of the odor activity values (OAVs) showed that 3-mercaptohexyl acetate was the most active odorant in the Marmajuelo and Verdello wines, as were 3-methylbutyl acetate in the Gual wine, beta-damascenone in the Malvasia wine, and ethyl octanoate in the white Listán wine. However, the most important differences between varieties...

To report a case of seizure-induced takotsubo cardiomyopathy with rare etiology and rarer complications. A 50-year-old woman had multiple epileptic seizures and later developed acute heart failure complicated by ventricular fibrillation and shock. A two-dimensional echocardiogram revealed apical ballooning of the left ventricle resembling a takotsubo (a Japanese fisherman's pot used to trap octopi). The apex was also hypokinetic. The hemodynamic abnormalities normalized with defibrillation, assisted ventilation, inotropic support, and pressor agents. More importantly, the apical ballooning deformity and systolic dysfunction reversed. The echocardiogram normalized three months later. A nuclear treadmill stress test was negative for ischemia. Apical ballooning of the left ventricle and hypokinesis are typical echocardiographic features in takotsubo cardiomyopathy, a stress-induced heart disease. It may follow severe emotional, physical, and neurologic stressors, in our rare case, ...

PyNTTTTGT oligodeoxinucleotides (ODNs) cause activation, proliferation and immunoglobulin secretion on B cells, and the expression of co-stimulatory molecules on plasmacytoid dendritic cells of primates. It has now been discovered that these ODNs are also active on rat cells. This fact allowed us to investigate the adjuvant properties of PyNTTTTGT ODNs in a human Hepatitis B vaccine using this animal model. A very significant increment, as compared with the antigen alone, was observed in the antibody production induced by vaccination with the recombinant Hepatitis B surface antigen adjuvated with the PyNTTTTGT prototype IMT504 ODN. Analysis of the IgG subclass distribution in the sera of vaccinated animals indicated that, although an increase was observed in the titer of all the IgG subclasses, the increase on the Th1-associated IgG2b subclass was clearly more pronounced. Remarkably, this effect on the IgG2b titer was observed even if alum, a Th2 promoting adjuvant, was present together with IMT504 in the vaccine formulation. The increase in the Th1 response induced by IMT504 was also suggested by in vitro gamma interferon secretion assays. Monkeys of the species Cebus apella immunized with the recombinant Hepatitis B surface antigen plus alum and IMT504 also showed titers of antibodies against the antigen several times superior to the titers observed in control animals immunized with the antigen plus alum without ODN. Since rat and monkey cells are significantly less immunostimulated "in vitro" by PyNTTTTGT ODNs than human cells, the present results reasonably predict a very good performance of these ODNs as adjuvants in human vaccination.

ABSTRACT The optimum instantaneous driving temperature of a solar cooling facility is determined along a day. The chillers compared use single effect cycles working with NH3/LiNO3, either conventional or hybridised by incorporating a low pressure booster compressor. Their performances are compared with a H2O/LiBr single effect absorption chiller as part of the same solar system. The results of a detailed thermodynamic cycle for the absorption chillers allow synthesizing them in a modified characteristic temperature difference model. The day accumulated solar cold production is determined using this optimum temperature during two sunny days in mid-July and mid-September, located in Madrid, Spain. The work shows the influences of operational variables and a striking result: selection of a time-constant temperature during all the day does not necessarily imply a substantial loss, being the temperature chosen a key parameter. The results indicate that the NH3/LiNO3 option with no boosting offers a smaller production above-zero Celsius degrees temperatures, but does not require higher hot water driving temperatures than H2O/LiBr. The boosted cycle offers superior performance. Some operational details are discussed.

ABSTRACT Wine aroma is very complex, and its olfactometric evaluation has to face several difficulties added to those linked to olfactometry. In the past, scientists have found many problems in the identification of the truly important odorants and huge efforts have been made in the isolation and identification of non-relevant volatile compounds. This has contributed to the idea that it is not possible to get actual — scientific and technological — advantages from the analysis of wine aroma. However, in the last 5 years most of the actually relevant aroma volatiles have been isolated and identified. What this means is that it is only now that it has become possible to evaluate the different methods and working strategies, and to design how olfactometric research should be conducted to be successful.

A method to analyse 2-methylpentanoic, 3-methylpentanoic and 4-methylpentanoic acids as well as cyclohexanecarboxylic acid has been developed and applied to wine and other alcoholic beverages. Selective isolation with solid phase extraction, derivatization with 2,3,4,5,6-pentafluorobenzyl bromide at room temperature for 30minutes, and further analysis by gas chromatography-mass spectrometry in negative chemical ionization mode provides detection limits between 0.4 and 2.4ng/L. Good linearity up to 3.6μg/L, satisfactory reproducibility (RSD<10%) and signal recovery of around 100% represent a robust method of analysis. Concentration data of these analytes in wine and other alcoholic beverages are reported for the first time. The levels found ranged from the method detection limits to 2630ng/L, 2040ng/L and 3810ng/L for 2-, 3- and 4-methylpentanoic acids, respectively, and to 1780ng/L for cyclohexanecarboxylic acid. There are significant differences depending on the type of wine or ...

Forty-five GM1-binding peptides were identified using phage-displayed peptides libraries of random peptides. Most have a motif containing a hydrophobic amino acid followed by a serine (S). Based on a GM1-binding assays, two of these GM1-binding peptides (named 15 and 40) were chosen to investigate its immunostimulatory properties when chemically coupled to antigens. Mice intra-nasally (i.n.) vaccinated with some of these complexes developed a better local and systemic antibody response than mice i.n. vaccinated with the respective uncoupled antigens. The efficiency of the complex GM1-binding peptide-antigen strongly depends on the composition and structure of both of the components of the complex.

Bone marrow (BM)-derived adult mesenchymal stem cells (MSCs) have the capacity to differentiate in vitro into different cell lines. This makes them a likely source for application in tissue repair therapies. Here, we report evidence indicating that, both in vivo and in vitro, IMT504, the prototype of the PyNTTTTGT class of immunostimulatory oligonucleotides, significantly increases the number of fibroblast colony-forming units (CFU-Fs) that originate MSCs. When rat BM cells were cultured with IMT504, the mean number of CFU-Fs increased about three times as compared with untreated controls (CFU-F: 19 +/- 6.3 vs. 6.8 +/- 2.0/2 x 10(6) seeded BM cells, p = .03). Furthermore, rats inoculated with IMT504 had a significantly higher number of CFU-Fs both in BM (CFU-F: 124 +/- 33 vs. 38 +/- 17/femur, p = .04) and in peripheral blood (animals with detectable CFU-Fs in circulation 8/12 vs. 2/12, p = .04) as compared with untreated animals. On the other hand, BM-derived adherent cells either treated in vitro with IMT504 or obtained from animals injected with IMT504 possess the capacity to differentiate to the osteogenic and adipogenic cell lineages as regular MSCs. Finally, we found that repair of a bone defect was accelerated in rats injected with IMT504 as compared with control animals (area with consolidated bone: 80% +/- 6.4% vs. 49% +/- 3.5%, p = .03, n = 10 rats per group). Importantly, when two human BM were cultured in the presence of IMT504, the mean number of fibroblastic adherent colonies also increased as compared with controls. These results suggest the possibility of clinical use of IMT504 in bone, and presumably other, tissue repair therapies.