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1.
Animals (Basel) ; 12(23)2022 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-36496835

RESUMEN

A bovine herd with a high prevalence of paratuberculosis (PTB) cohabiting with a population of pigeons was studied (2011−2020). After finding the disease in 2011, annual monitoring was performed in 2012−2014 by obtaining blood samples for ELISA and intradermal tuberculinization (IT) tests for Mycobacterium avium subsp. paratuberculosis (MAP). Positive animals were eliminated. PTB prevalence dropped from 10% to 0% but returned to similar values (9.5%) after 6 years without tests. In all animals, Ac values according to the optical density (OD) determined by ELISA increased each year and could be used to isolate herds close to the cutoff point to improve PTB control. Possible reservoirs were considered after evaluating the little success of the PTB control program, and the population of feral pigeons was studied. Specifically, 10% of the pigeon population (n = 13) was necropsied. Samples of intestine, feces, and foot skin for PCR study for MAP and samples of terminal intestine for histopathological analysis were taken. Eleven pigeons were PCR-positive against MAP, in the intestine (10/11), foot skin (3/11), and feces (1/11). The presence of MAP in pigeon feet could demonstrate its role as a mechanical disseminator of PTB, while the presence in pigeon intestine and feces could also suggest its role as a reservoir.

2.
Waste Manag ; 120: 280-289, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33316548

RESUMEN

The electrochemical energy storage performance of activated carbons (ACs) obtained from coffee-derived biowastes was assessed. ACs were obtained from spent coffee ground second waste, after polyphenol extraction, by means of a hydrothermal process followed by physical or chemical activation. The resulting materials exhibited microporous structures with a total specific area between 585 and 2330 m2·g-1. Scanning electron microscopy (SEM) revealed a highly porous microstructure in the case of the chemically activated carbons, while physical activation led to a cracked micro-sized morphology. The electrochemical properties of the materials for supercapacitor applications were investigated in 1 M Na2SO4. After chemical activation, the coffee-derived material displayed a capacitance of 84 F·g-1 at 1 A·g-1 in a 1.9 V voltage window, with 70% capacitance retention at 10 A·g-1 and 85% retention after 5000 cycles of continuous charge-discharge. This work demonstrates how coffee secondary biowaste can be conveniently activated to perform as electrochemical energy storage material, contributing to its revalorization and reinsertion in a circular economy.


Asunto(s)
Carbón Orgánico , Café , Capacidad Eléctrica , Electrodos , Porosidad
3.
Front Chem ; 8: 686, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32923425

RESUMEN

Revalorizing organic biowaste is critical to achieve a full circular economy, where waste is transformed into resources. One of the main strategies is to produce activated carbons and use them as functional materials for electrochemical energy storage. In this study, winemaking wastes, bagasse (BAG), and cluster stalks (CS) were recovered and used in the preparation of activated carbons by a hydrothermal process. Then, they were chemically activated using KOH and investigated for electrochemical capacitor applications. The activation treatment resulted in microporous structures, characterized by a type I isotherm for low partial pressures (P/P 0), and a type IV for higher pressures, as observed by Brunauer-Emmett-Teller surface analysis, with specific surfaces of 1,861 and 2,662 m2·g-1 for BAG and CS, respectively. These microporous structures were also investigated by means of scanning electron microscopy, revealing a high porous degree. Micro-Raman spectroscopy and X-ray photoelectron spectroscopy measurements displayed bands associated to disorder of the structure of the carbonaceous material. The electrochemical performance of the resulting materials was investigated for electrochemical energy storage applications, as supercapacitor electrode, in 1 M KOH aqueous electrolyte. These biowaste-derived materials displayed electrochemical double-layer capacitance, with 129 F·g-1 at 10 A·g-1 in the 0.1 to -1.0 V vs. saturated calomel electrode. For that reason, they are pin-pointed as potential negative electrodes for electrochemical double-layer supercapacitors and hybrid or asymmetric supercapacitors.

4.
Front Psychol ; 11: 606180, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33510681

RESUMEN

Since March 14, 2020, Spanish citizens have been confined to their homes due to the impact of the COVID-19 pandemic. Participating in musical activities has been associated with reduced anxiety and increased subjective wellbeing. The aim of this study is to analyze how Spanish citizens used music during the lockdown period. We also study perceptions of the impact music has in everyday life, in particular examining the respondents' insights into the effects of listening to music in situations of isolation. The study was conducted using the MUSIVID19 questionnaire administered to a total of 1868 Spanish citizens. The results indicate that during lockdown, respondents perceived an increase in the time they devoted to musical activities such as listening, singing, dancing or playing an instrument. The participants also reported using music to cope with the lockdown, finding that it helped them to relax, escape, raise their mood or keep them company. The findings suggest an improvement in their perception of the value of music in personal and social wellbeing during the lockdown. However, the study reveals significant differences in the use and perceptions of music according to respondents' personal situations. Age and feelings of vulnerability may lead to more conservative uses of musical practice and to more moderate perceptions of the positive values of music.

5.
RSC Adv ; 9(33): 18853-18862, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35516854

RESUMEN

Decoupling energy supply from fossil fuels through electrification and sustainable energy management requires efficient and environmentally low-impact energy storage technologies. Potential candidates are charge storage electrodes that combine nickel and cobalt hydroxides with reduced graphene oxide (rGO) designed to achieve high-energy, high-power density and long cycling lifetimes. An early eco-efficiency analysis of these electrodes seeks to examine the impacts of materials and processes used in the synthesis, specifically while focusing on the use of rGO. The emerging electrodes synthesized by means of electrodeposition, are further compared with electrodes obtained by an alternative synthesis route involving co-precipitation. Life cycle assessment (LCA) method was applied to compare a baseline nickel-cobalt hydroxide electrode (NCED), the focal electrode integrating rGO (NCED-rGO), and the benchmark co-precipitated electrode (NCCP), for delivering the charge of 1000 mA h. Contribution analysis reveals that the main environmental hotspots in the synthesis of the NCED-rGO are the use of electricity for potentiostat, ethanol for cleaning, and rGO. Results of comparison show significantly better performance of NCED-rGO in comparison to NCED across all impact categories, suggesting that improved functionalities by addition of rGO outweigh added impacts of the use of material itself. NCED-rGO is more impactful than NCCP except for the indicators of cumulative energy demand, climate change, and fossil depletion. To produce a functional equivalent for the three electrodes, total cumulative energy use was estimated to be 78 W h for NCED, 25 W h for NCED-rGO, and 35 W h for NCCP. Sensitivity analysis explores the significance of rGO efficiency uptake on the relative comparison with NCCP, and potential impact of rGO on the category of freshwater ecotoxicity given absence of removal from the process effluent. Scenario analysis further shows relative performance of the electrodes at the range of alternative functional parameters of current density and lifetime. Lastly, the environmental performance of NCED-rGO electrodes is discussed in regard to technology readiness level and opportunities for design improvements.

6.
Vet Microbiol ; 171(1-2): 139-46, 2014 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-24794166

RESUMEN

This study reports the performance of the single intradermal tuberculin (SIT) test and the interferon-gamma (IFN-γ) assay for Mycobacterium bovis in a cattle herd with high prevalence of paratuberculosis (PTB). A total of 58/350 animals were selected for necropsy based on one or more of the following criteria: positive to SIT, IFN-γ, a breeding cow that seroconverted to PTB and showed signs compatible with a wasting disease. Infection status was determined by post mortem diagnostic tests that included histopathology examination, mycobacterial cultures and PCR identification for M. bovis and Mycobacterium avium subsp. paratuberculosis (MAP). In 7/58 animals primary tuberculosis (TB) lesions, affecting only the retropharyngeal and/or mediastinal lymph nodes, were found; 3/7 animals were found SIT positive. PTB was confirmed in 35/58 animals, of which 30 had seroconverted and 14 had typical clinical signs. 45/58 animals were IFN-γ(+) using the most stringent criterion (cut-off point ≥ 0.05); however, IFN-γ test was only positive in 33 animals when using a higher threshold (cut-off point ≥ 0.1). Three animals co-infected also showed extensive TB and diffuse PTB lesions. These results show that the combined use of SIT and IFN-γ, as interpreted using official guidelines, detected all confirmed cases of TB. Individually, the sensitivity of the SIT was inadequate to diagnose TB-positive animals with an advanced stage of PTB. The large number of IFN-γ(+) animals with no visible TB lesion could be due, in part, to some protection conferred by prior infection with MAP.


Asunto(s)
Enfermedades de los Bovinos/diagnóstico , Enfermedades de los Bovinos/microbiología , Mycobacterium bovis/fisiología , Paratuberculosis/complicaciones , Prueba de Tuberculina/veterinaria , Tuberculosis Bovina/complicaciones , Tuberculosis Bovina/diagnóstico , Animales , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/patología , Coinfección , Femenino , Interferón gamma/inmunología , Mycobacterium avium subsp. paratuberculosis/fisiología , Mycobacterium bovis/genética , Mycobacterium bovis/inmunología , Paratuberculosis/inmunología , Paratuberculosis/patología , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/inmunología , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , España , Tuberculina/inmunología , Prueba de Tuberculina/normas , Tuberculosis Bovina/patología
7.
Nanomaterials (Basel) ; 3(3): 325-356, 2013 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-28348339

RESUMEN

Graphene and its derivatives combine a numerous range of supreme properties that can be useful in many applications. The purpose of this review is to analyse the photoelectrochemical properties of pristine graphene, graphene oxide (GO) and reduced graphene oxide (rGO) and their impact on semiconductor catalysts/quantum dots. The mechanism that this group of materials follows to improve their performance will be cleared by explaining how those properties can be exploited in several applications such as photo-catalysts (degradation of pollutants) and photovoltaics (solar cells).

8.
FEMS Yeast Res ; 7(2): 304-16, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17132143

RESUMEN

The inoculation of active dry wine yeast (ADWY) is one of the most common practices in winemaking. We have used DNA microarray technology to examine the genetic expression patterns of a commercial ADWY strain after rehydration. After rehydration of ADWY for 30 min, a further hour in water after rehydration did not lead to any relevant changes in global gene expression. Expression changes in rehydrated cells upon incubation in a sorbitol solution at the same osmotic pressure as in complete must were rather limited, whereas the presence of fermentable carbon sources or the complete medium (synthetic must) produced very similar transcriptional responses. The main responses were the activation of some genes of the fermentation pathway and of the nonoxidative branch of the pentose phosphate pathway, and the induction of a huge cluster of genes related to ribosomal biogenesis and protein synthesis. The presence of cycloheximide in fermentable medium produced a similar but stronger transcriptional response. Whereas the viabilities of rehydrated cells incubated for 1 h in these different media were similar, yeast vitality, which represents the fermentative capacity of the yeast, showed a positive correlation with the availability of a fermentable carbon source.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiología , Agua/farmacología , Vino/microbiología , Medios de Cultivo , Fermentación , Regulación Fúngica de la Expresión Génica , Genoma Fúngico , Respuesta al Choque Térmico , Presión Osmótica , Proteoma , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
9.
FEMS Yeast Res ; 6(8): 1167-83, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17156014

RESUMEN

Wine produced at low temperature is often considered to have improved sensory qualities. To investigate the effects of temperature on winemaking, the expression patterns during the industrial fermentation process carried out at 13 degrees C and 25 degrees C were compared, and correlated with physiological and biochemical data, including viability, fermentation byproducts and lipid content of the cells. From a total of 535 ORFs that were significantly differentially expressed between the 13 degrees C and 25 degrees C fermentations, two significant transcription programmes were identified. A cold-stress response was expressed at the initial stage of the fermentation, and this was followed by a transcription pattern of upregulated genes concerned with the cell cycle, growth control and maintenance in the middle and late stages of the process at 13 degrees C with respect to 25 degrees C. These expression patterns were correlated with higher cell viability at low temperature. The other relevant transcriptomic difference was that several genes implicated in cytosolic fatty acid synthesis were downregulated, while those involved in mitochondrial short-chain fatty acid synthesis were upregulated in the fermentation process conducted at 13 degrees C with respect to that at 25 degrees C. These transcriptional changes were qualitatively correlated with improved resistance to ethanol and increased production of short-chain (C(4)-C(8)) fatty acids and their corresponding esters at 13 degrees C as compared to 25 degrees C. While this increase of ethyl esters may account in part for the improved sensory quality of wine fermented at 13 degrees C, it is still unclear how the esterification of the short-chain fatty acids takes place. On the basis of its strong upregulation at 13 degrees C, we propose a possible role of IAH1 encoding an esterase/ester synthase in this process.


Asunto(s)
Fermentación , Saccharomyces cerevisiae/metabolismo , Temperatura , Vino/microbiología , Frío , Ácidos Grasos/metabolismo , Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Análisis de Secuencia por Matrices de Oligonucleótidos , Fosfolípidos/metabolismo , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Regulación hacia Arriba
10.
J Agric Food Chem ; 53(4): 1003-11, 2005 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-15713012

RESUMEN

Low-temperature fermentations (13 degrees C) are considered to improve wine aromatic profiles. However, because the risk of stuck and sluggish fermentations is high, these fermentations are not common. The aim of this paper was to analyze the effect of different preadaptation protocols in two commercial wine strains on the fermentation and some wine parameters. Preadaptation is understood to be the process between the rehydration of active dry yeast and the inoculation. In this study, it consisted of preparing a fermentation starter (addition of yeast grown at 25 degrees C) or inocula preadapted at low temperatures (as before, but grown at a fermentation temperature of 13 or 17 degrees C). These results were compared with those of rehydrated active dry yeast, and a commercial "cryotolerant" yeast was used as a reference. General fermentation kinetic parameters, yeast imposition, nitrogen consumption, and main wine products were analyzed. The results showed that the preadaptation of a yeast could improve the fermentation performance, although this improvement was strain-dependent. Low-temperature fermentations also had some general effects: reduction of acetic acid and fusel alcohol production and increased concentrations of glycerol. When the yeast performed better in fermentation because of preadaptation, nitrogen consumption was faster and the wine's "negative" attributes (acetic acid, fusel alcohols) were significantly reduced. Thus, in some strains, preadaptation could be an effective mechanism for improving low-temperature fermentation, which also significantly reduces detrimental wine attributes.


Asunto(s)
Frío , Manipulación de Alimentos/métodos , Saccharomyces cerevisiae/metabolismo , Vino , Adaptación Fisiológica , Cinética , Nitrógeno/metabolismo , Odorantes/análisis , Control de Calidad , Vino/análisis
11.
Appl Microbiol Biotechnol ; 66(5): 560-6, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15375634

RESUMEN

Trehalose metabolism in yeast has been related to stress and could be used as a stress indicator. Winemaking conditions are stressful for yeast and understanding trehalose metabolism under these conditions could be useful for controlling alcoholic fermentation. In this study, we analysed trehalose metabolism of a commercial wine yeast strain during alcoholic fermentation by varying the nitrogen levels from low (below adequate) to high (excess). We determined trehalose, nitrogen, sugar consumption and expression of NTH1, NTH2 and TPS1. Our results show that trehalose metabolism is slightly affected by nitrogen availability and that the main consumption of nitrogen occurs in the first 24 h. After this period, nitrogen is hardly taken up by the yeast cells. Although nitrogen and sugar are still available, no further growth is observed in high concentrations of nitrogen. Increased expression of genes involved in trehalose metabolism occurs mainly at the end of the growth period. This could be related to an adaptive mechanism for fine tuning of glycolysis during alcoholic tumultuous fermentation, as both anabolic and catabolic pathways are affected by such expression.


Asunto(s)
Nitrógeno/metabolismo , Trehalosa/metabolismo , Vino/microbiología , Levaduras/metabolismo , Fermentación , Regulación Fúngica de la Expresión Génica , Agua/metabolismo , Levaduras/efectos de los fármacos , Levaduras/crecimiento & desarrollo
12.
Int J Food Microbiol ; 86(1-2): 153-61, 2003 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-12892930

RESUMEN

The metabolism of glycogen and trehalose was analysed in a wine yeast strain fermenting at 25 and 13 degrees C. Trehalose and glycogen degradation were completed during the lag phase of fermentation. Ammonia was taken up rapidly and once it had been reduced to negligible amounts, the synthesis of trehalose started. Glycogen followed a similar pattern. If trehalose synthesis was taken as a stress indicator, the fermentation at 13 degrees C could not be considered stressful because the maximum concentrations are similar at both temperatures. In industrial fermentations, and after a preadaptation in grape must for several hours at 18 degrees C, the lag phase was reduced significantly, and this may be why trehalose and glycogen were completely depleted at the beginning of the low temperature fermentation. Various preadaptation conditions were tested so that their influence on trehalose and glycogen degradation could be determined. The presence of fermentable carbon sources, such as glucose or fructose, triggered the mobilisation and use of trehalose. However, just increasing the osmotic pressure did not reduce the trehalose content. No such differences were observed in glycogen metabolism.


Asunto(s)
Fermentación , Glucógeno/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Saccharomyces cerevisiae/metabolismo , Trehalosa/metabolismo , Vino/microbiología , Microbiología de Alimentos , Temperatura , Agua/metabolismo
13.
Physiol Plant ; 115(2): 175-182, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12060233

RESUMEN

Aquaporins are ubiquitous membrane channel proteins that facilitate and regulate the permeation of water across biological membranes. Aquaporins are members of the MIP family and some of them seem to be also able to transport other molecules such as urea or glycerol. In the plant kingdom, a single plant expresses a considerably large number of MIP homologues. These homologues can be subdivided into four groups (PIP, TIP, NIP, SIP) with highly conserved amino acid sequences and intron positions in each group. Since their discovery, advancing knowledge of their structure led to an understanding of the basic features of the water transport mechanism. An optimal water balance is essential to the homeostasis of most organisms, and aquaporins may be one of the mechanisms involved under changing environmental and developmental conditions. In fact, this may be one reason for the abundance and diversity of aquaporins, in particular in plants. In addition, exposure to different types of stress alters water relations and thus, aquaporins may be involved in stress responses as well. The transcriptional and/or post-translational regulation of aquaporins would determine changes in membrane water permeability. Both phosphorylation and translocation to/from vesicles have been reported as post-translational mechanisms. However, translocation in plants has not yet been shown. Although significant advances have been achieved, complete understanding of aquaporin function and regulation remains elusive.

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