Ni‐doped chromite anodes were integrated into electrolyte‐supported cells (ESC) with 5×5 cm2 size and investigated in fuel cell mode with H2/H2O fuel gas. Both a stoichiometric and a nominally A‐site ...deficient chromite anode material showed promising performance at 860 °C approaching the ones of state‐of‐the‐art Ni/Gd‐doped ceria (CGO) anodes. While the difference in polarization resistance was small, an increased ohmic resistance of the perovskite anodes was observed, which is related to their limited electronic conductivity. Increasing the chromite electrode thickness was shown to enhance performance and stability considerably. Degradation increased with current density, suggesting its dependency on the electrode potential, and could be reversed by redox cycling. Sulfur poisoning with 20 ppm hydrogen sulfide led to rapid voltage drops for the chromite anodes. It is discussed that Ni nanoparticle exsolution facilitates hydrogen dissociation to the extent that it is not rate‐limiting at the investigated temperature unless an insufficiently thick electrode thickness is employed or sulfur impurities are present in the feed gas.
Appearing from nowhere: Alternative perovskite anodes for solid oxide fuel cells show the exsolution of anchored Ni nanoparticles under reducing conditions. In the present work, their performance and durability is compared to commercial electrodes.
Protected areas are a global cornerstone of biodiversity conservation and restoration. Yet freshwater biodiversity is continuing to decline rapidly. To date there has been no formal review of the ...effectiveness of protected areas for conserving or restoring biodiversity in rivers, lakes, and wetlands. We present the first assessment using a systematic review of the published scientific evidence of the effectiveness of freshwater protected areas. Systematic searches returned 2,586 separate publications, of which 44 provided quantitative evidence comprising 75 case studies. Of these, 38 reported positive, 25 neutral, and 12 negative outcomes for freshwater biodiversity conservation. Analysis revealed variable relationships between conservation effectiveness and factors such as taxa assessed, protected area size and characteristics, International Union for Conservation of Nature (IUCN) protected area category, and ecoregion. Lack of effectiveness was attributed to many anthropogenic factors, including fishing (often with a lack of law enforcement), water management (ion, dams, and flow regulation), habitat degradation, and invasive non‐native species. Drawing on the review and wider literature we distil eight lessons to enhance the effectiveness of protected areas for freshwater biodiversity conservation. We urge policymakers, protected area managers, and those who fund them to invest in well‐designed research and monitoring programs and publication of evidence of protected area effectiveness.
The almond crop has high economic importance on a global scale, but its sensitivity to salinity stress can cause severe yield losses. Salt-tolerant rootstocks are vital for crop economic feasibility ...under saline conditions. Two commercial rootstocks submitted to salinity, and evaluated through different parameters, had contrasting results with the survival rates of 90.6% for 'Rootpac 40' (tolerant) and 38.9% for 'Nemaguard' (sensitive) under salinity (Electrical conductivity of water = 3 dS m
). Under salinity, 'Rootpac 40' accumulated less Na and Cl and more K in leaves than 'Nemaguard'. Increased proline accumulation in 'Nemaguard' indicated that it was highly stressed by salinity compared to 'Rootpac 40'. RNA-Seq analysis revealed that a higher degree of differential gene expression was controlled by genotype rather than by treatment. Differentially expressed genes (DEGs) provided insight into the regulation of salinity tolerance in Prunus. DEGs associated with stress signaling pathways and transporters may play essential roles in the salinity tolerance of Prunus. Some additional vital players involved in salinity stress in Prunus include CBL10, AKT1, KUP8, Prupe.3G053200 (chloride channel), and Prupe.7G202700 (mechanosensitive ion channel). Genetic components of salinity stress identified in this study may be explored to develop new rootstocks suitable for salinity-affected regions.
We apply the independent cascade network inference model to a large database of music videos to infer the structure of the global network of music diffusion. The derived network reveals an intricate ...topology-fully interconnected, exhibiting a modular structure, and characterized by asymmetric links. We explore the relationship between the identified bilateral cultural diffusion pathways and the geographical and cultural distances among countries, and key socioeconomic interactions such as international trade and migration. Additionally, we use a gravity model to ascertain the factors contributing to both the formation and the intensity of the estimated diffusion channels between countries. Our findings reveal that cultural, geographical, and historical factors serve as primary drivers of musical diffusion, downplaying the importance of economic factors. This study posits that these elements exert considerable force in shaping musical preferences across nations, making the emergence of a homogeneous global musical culture improbable. This exploration adds valuable insights to the discourse on the globalization of music and its potential cultural implications.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Recent studies show that quarantine and lockdown are effective measures for controlling COVID-19 outbreaks, but may be an unpleasant experience with psychological consequences. For this reason, the ...main aim of this study was to determine which personal sociodemographic and psychological variables are related to adapting to lockdown in a Spanish population. Questionnaires were administered to 2,055 individuals (60.7% women) who were resident in Spain and aged between 18 and 80 years old. We also administered some items related to feelings and behaviors during lockdown. The results showed that sex and age are variables to be taken into account. In fact, women tended to show greater stress, a more pessimistic attitude, and lower self-esteem. However, older people adapted better to lockdown although they were also more worried. Married people also adapted better although they too were more worried. The results also showed that more resilient people, with higher subjective happiness and life satisfaction, develop strategies for adapting positively to adversity, and tend to adapt better to lockdown, with more positive attitudes and behaviors. In terms of personality traits, higher neuroticism and lower extraversion were related to worse adaptation to lockdown. This study also showed that lockdown has had a negative psychological impact on those people who did not adapt well to the situation and the changes during the first 4 weeks of lockdown.
Ligninolytic peroxidases are enzymes of biotechnological interest due to their ability to oxidize high redox potential aromatic compounds, including the recalcitrant lignin polymer. However, ...different obstacles prevent their use in industrial and environmental applications, including low stability towards their natural oxidizing-substrate H2O2. In this work, versatile peroxidase was taken as a model ligninolytic peroxidase, its oxidative inactivation by H2O2 was studied and different strategies were evaluated with the aim of improving H2O2 stability. Oxidation of the methionine residues was produced during enzyme inactivation by H2O2 excess. Substitution of these residues, located near the heme cofactor and the catalytic tryptophan, rendered a variant with a 7.8-fold decreased oxidative inactivation rate. A second strategy consisted in mutating two residues (Thr45 and Ile103) near the catalytic distal histidine with the aim of modifying the reactivity of the enzyme with H2O2. The T45A/I103T variant showed a 2.9-fold slower reaction rate with H2O2 and 2.8-fold enhanced oxidative stability. Finally, both strategies were combined in the T45A/I103T/M152F/M262F/M265L variant, whose stability in the presence of H2O2 was improved 11.7-fold. This variant showed an increased half-life, over 30 min compared with 3.4 min of the native enzyme, under an excess of 2000 equivalents of H2O2. Interestingly, the stability improvement achieved was related with slower formation, subsequent stabilization and slower bleaching of the enzyme Compound III, a peroxidase intermediate that is not part of the catalytic cycle and leads to the inactivation of the enzyme.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Invasive species are considered to be a leading cause of the decline of threatened species. However, this view has been disputed because much of the evidence base is anecdotal. This systematic ...review, through an extensive, repeatable search using agreed selection criteria, examined the available scientific evidence on invasive species’ interactions with the 1363 endangered and threatened species protected under the United States Endangered Species Act (ESA). The review found scientific evidence available for 116 endangered or threatened species (8.5% of the ESA list). Of these, 85 species (6.2%) were reported as being negatively impacted by invasive species: 39 located on the continental US and 39 on islands, with seven marine species. The relative percentages of species impacted differed according to location: 4.3% (n = 906) on the continental US, 9.3% (n = 420) on islands. It was found that predation by invasive vertebrates on birds on islands and competition between invasive plants and endangered or threatened plants on the mainland were the main mechanisms of impact. The results of this study contrast markedly with a previous study which found that 49% of imperilled species in the United States were threatened by invasive species. Further research is essential in order to evaluate the impact of invasive species on imperilled species on the ESA list; this would help to reduce the high degree of uncertainty regarding the threat of invasive species due to the lack of empirical information.
El presente artículo tiene como objetivo identificar algunas líneas de discusión y de valoración crítica en torno a la película peruana La muralla verde (Robles Godoy, 1970). Dos textos firmados por ...Desiderio Blanco e Isaac León Frías en 1970 —el primero publicado en el semanario Oiga y el segundo en la revista Hablemos de Cine— se contrastan con dos artículos escritos por Sebastián Pimentel para la revista Godard! en los años 2005 y 2010. Los hallazgos se agrupan en tres dimensiones: las referencias a la puesta en escena cinematográfica —el empleo de planos y movimientos de cámara, sonido, actuaciones y uso del montaje como recurso temporal—, a las construcciones simbólicas —el significado de la selva y el enfrentamiento entre burocracia e individuo— y a la condición autoral del cineasta. El análisis permite concluir que las posturas que se pueden identificar en los textos de valoración crítica de La muralla verde y de la obra de Armando Robles Godoy, responden a distintos condicionamientos conceptuales, sustratos ideológicos, métodos de acercamiento y etapas de desarrollo del arte cinematográfico. Las películas, como sucede con todas las obras de arte, se resignifican en el tiempo. Por lo tanto, ciertos elementos que en su momento no fueron valorados pueden ser redescubiertos.
Many lactic acid bacteria synthesize extracellular polysaccharides (exopolysaccharides, EPSs) with a large variation in structure and potential functional properties. Although EPS production can ...produce detrimental effects in alcoholic beverages, these polymers play an important role in the rheological behavior and texture of fermented products. In this work, EPS production by two Lactobacillus suebicus strains, which were isolated from ropy ciders, was examined in a semidefined medium. The existence of priming glycosyltransferase encoding genes was detected by PCR. In addition, the preliminary characterization of the polymers was undertaken. Molecular masses were determined by size exclusion chromatography revealing the presence of two peaks, corresponding to polymers of high- and low-molecular-weight in all fractions. The composition of the EPS fractions was analyzed by gas chromatography–mass spectrometry after acid hydrolysis, revealing that they contained glucose, galactose, N-acetylglucosamine and phosphate, although in different ratios, suggesting that a mixture of polysaccharides is being synthesized. We also examined the influence of the sugar source (glucose, ribose, xylose, or arabinose) and pH conditions on growth and EPS production.
•Two Lactobacillus suebicus strains were isolated from ropy cider of Basque Country (Spain).•Both strains synthesize a produce a mixture of complex heteropolysaccharides.•All fractions contain a mixture of high- and low-molecular-weight polysaccharides.•The synthesis of exopolysaccharides is dependent on the carbohydrate source.
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