Valence change of praseodymium in Pr0.5Ca0.5CoO3 investigated by x-ray absorption spectroscopy

X-ray absorption spectroscopy measurements in Pr0.5Ca0.5CoO3 were performed at the Pr M4,5, Pr L3, and Ca L2,3 absorption edges as a function of temperature below 300 K. Ca spectra show no changes down to 10 K while a noticeable thermally dependent evolution takes place at the Pr edges across the metal-insulator transition. Spectral changes are analyzed by different methods, including multiple scattering simulations, which provide quantitative details on an electron loss at Pr 4f orbitals. We conclude that in the insulating phase a fraction [15(+5)%] of Pr3+ undergoes a further oxidation to adopt a hybridized configuration composed of an admixture of atomic-like 4f1 states (Pr4+) and f- symmetry states on the O 2p valence band (Pr3+L states) indicative of a strong 4f- 2p interaction.Comment: 19 pages (.doc), 4 figures, Phys. Rev. B, in pres

Quantifying the relative contribution of ante- and post-mortem factors to the variability in beef texture

This study aims to investigate the relative contribution of ante- and post-mortem factors to the final quality of beef. In all, 112 steers (four breed-crosses) were arranged in a 2 3 2 3 2 factorial experimental including production system, growth implant and b-adrenergic agonist strategies. Carcasses were suspended by the Achilles tendon or the aitch bone and meat was aged for 2/6/13/21/27 days (longissimus muscle) or 2/27 days (semimembranosus muscle). Meat quality traits related to beef texture were measured. Statistical analyses were developed including ante- and post-mortem factors and their relative contribution to the variability observed for each measured trait was calculated. The main factor responsible for the variability in sarcomere length was the suspension method (91.1%), which also influenced drip-loss (44.3%). Increasing the percentage of British breeds increased (P , 0.05) the intramuscular fat content in longissimus muscle, but only when implants were not used. Thus, the breed-cross, implant strategy and their interaction were responsible for .58% of the variability in this trait. The variability in instrumental and sensory tenderness was mainly affected by post-mortem factors (carcass suspension, ageing time and their interaction), explaining generally , 70% of the variability in these traits. Breed-cross was the second most important effect ( ,15%) when carcass suspension was not considered in the model, but still ageing time was responsible for a much larger proportion of the variability in tenderness (.45%). In conclusion, post-mortem handling of the carcasses may be much more effective in controlling beef tenderness than pre-mortem strategies

Ensamblar flores y cultivar hogares. Trabajo y género en Colombia [Reseña]

Bajo las premisas de la trascendencia que tienen las comunidades sociales en la vida de los individuos y de que “los procesos de ganarse la vida están culturalmente moldeados” (Gudeman, 1986, citado en Fridemann, 2008: 29), la autora recorre aspectos de la historia, de las condiciones de la producción de flores y de los ensamblajes para mercado globales, así como rasgos de la cotidianidad de las personas que allí laboran y de sus hogares, de las relaciones de género y de las historias laborales

Has cupper ion any effect on Sinorhizobium Melitoili bacteria?

Proceedings of the I Congress PIIISA celebrado en la Estación Experimental del Zaidín, Granada, el 26 de abril de 2012.Sinorhizobium meliloti is a soil bacterium that in symbiosis with Alfalfa leguminous plants fixes N2 to ammonia. This process occurs after an intimate communication between host and microsimbiont in the rhizosphere niche. This soil bacterium may suffer biotic and abiotic stresses in this complex environment. Resistance to any of this stresses can be an advantage for this type of bacteria. In this work we test the effects of Cupper ion in the bacterium Sinorhizobium meliloti. We found an effect on pigmentation and this effect is specific of each isolate (i.e. it is very pronounced for the isolate AK83 from Aral sea in Russia). On the other hand, comparison of Cupper ion resistance phenotype between isolates 1021 and GR4 suggests that the resistance of GR4 could be due to a set of 10 genes found in the cryptic plasmid pRmeGR4a of this strain. However, this resistance phenotype also appears in other isolates, and it could be explained by an alternative phenotype as Exopolysaccaride production (EPS+).It was supported mainly by research project MICINN Consolider‐Ingenio 2010. CSD2009‐00006; Scientific research by Young Students in Science (PIIISA2012; http://emc2astronomy.blogspot.com/).Peer reviewe

Essential ocean variables and high value biodiversity areas: Targets for the conservation of marine megafauna

Effective conservation and management measures are needed to face the unprecedented changes that marine ecosystems, and particularly marine megafauna, are suffering. These measures require the identification of highvalue biodiversity areas (HVBAs) which in turn require the identification of the essential ocean variables (EOVs) that shape the environmental envelope of communities (i.e. space defined by a set of environmental variables). The aim of this study was to delineate and characterise the HVBAs for the north and northwestern Spanish seabird and cetacean community taking advantage of the sightings collected during the annual PELACUS oceanographic survey (2007–2016). We used distance sampling methodology to analyse the species detectability based on environmental conditions. Then, we delimitated the HVBAs and identified the EOVs defining the environmental envelope of the community based on a spatio-temporal modelling approach using Generalized Additive Models. Overall, the main environmental variables driving species abundance were the sea surface temperature (SST), the distance to the shelf-break and the chlorophyll-a concentration (Chl-a). The SST and Chla were identified as dynamic EOVs due to their highest relative predictor importance, driving the environmental envelope and shaping areas of higher density. HVBAs were located mainly over the northwestern Spanish waters and decreased towards the inner Bay of Biscay remaining spatially stable over the study period. By identifying community-level HVBAs, we can understand the underlying ecological and oceanographic processes driving the spatio-temporal patterns of biological communities, such as those composed by seabirds and cetaceans. This information would identify conservation targets to assist the allocation of management resources. In addition, the location of HVBAs can help to fulfil the emergent need for sound spatial information to support the implementation of marine spatial planning.En prens

La Responsabilidad social empresarial y los objetivos del desarrollo sostenible (ODS).

The Sustainable Development Goals (SDGs) are an opportunity for companies to expand Corporate Social Responsibility (CSR), an initiative that is one of the global efforts to translate sustainable development into something concrete and measurable. In this challenge, companies have been included as a relevant actor to achieve them and today business organizations should be aware of the broad benefits that this entails. In this sense, the objective of the research was to describe the operations of an industrial and engineering services company in the Central-Western region, in such a way as to diagnose whether it carries out corporate social responsibility actions in accordance with the Sustainable Development Goals. (SDGs), included in the CEPAL document Agenda 2030 and the Sustainable Development Goals An opportunity for Latin America and the Caribbean. The results show that even though the company's key stakeholders were not aware of the existence of the SDGs and their impact on society, their operations incorporate practices and policies aimed at achieving them. Finally, a methodology was suggested into the work recommended by the Official Chamber of Commerce, Industry and Navigation of Valencia, Spain, as a guide for companies to expand their CSR practices, which was adapted according to the characteristics of the company that is the object of the study.Los Objetivos del Desarrollo Sostenible (ODS) son una oportunidad para que las empresas amplíen la Responsabilidad Social Empresarial (RSE), iniciativa que constituye uno de los esfuerzos globales por traducir en algo concreto y medible el desarrollo sostenible. En este desafío, han sido incluidas las empresas como un actor relevante para la consecución de los mismos y en la actualidad las organizaciones empresariales deberían ser conscientes de los amplios beneficios que esto acarrea. En tal sentido, el objetivo de la investigación fue describir las operaciones de una empresa de servicios industriales y de ingeniería de la región Centroccidental, de tal manera que permitiera diagnosticar si la misma realiza acciones de responsabilidad social empresarial en función a los Objetivos de Desarrollo Sostenible (ODS), recogidos en el documento de la CEPAL Agenda 2030 y los Objetivos de Desarrollo Sostenible Una oportunidad para América Latina y el Caribe. Los resultados demuestran que a pesar de que los actores clave de la empresa no tenían conocimiento de la existencia de los ODS y su impacto en la sociedad, en sus operaciones se incorporan prácticas y políticas encaminadas a su consecución. Finalmente en el trabajo se propuso una metodología que recomienda la Cámara Oficial de Comercio, Industria y Navegación de Valencia, España, como guía para que las empresas amplíen sus prácticas de RSE, la misma fue adaptada en función a las características de la empresa objeto de estudio

Fuzzy approach for risk assessment of brominated flame retardants in aquatic ecosystems

Brominated flame retardants (BFR) are pollutants that represent a threat to both human health and environment due to their industrial use, their persistence and their ability to bioaccumulate and biomagnify in food chains, especially in the aquatic one. For the last ten years contamination levels for this type of compounds have been reported for European, North American and Asian human tissue, sediments and biota samples [1-3]. However, monitoring efforts into the assessment of BFRs contamination levels in Latin America are scarce. In this study, a model for the evaluation of the environmental risk of BFRs in the aquatic ecosystems has been developed. It has been based on a technical application of the Fuzzy Theory [4]. In particular, three interconnected Fuzzy Inference Systems (FIS) have been created through the use of the Fuzzy Toolbox in Matlab. In order to improve and make the model scientifically robust, several international experts have been questioned about different information required to build the fuzzy system. Information from 38 questionnaires have been collected and statistically treated.Preprin