264 research outputs found
Intensive monitoring suggests population oscillations and migration in wild boar Sus scrofa in the Pyrenees
El seguimiento intensivo sugiere la existencia de oscilaciones demográficas y movimientos migratorios en las poblaciones de jabalí (Sus scrofa) en los Pirineos
Muy pocos estudios recientes han analizado la variabilidad local de las poblaciones de jabalí (Sus scrofa) en Europa occidental, lo que limita nuestra comprensión de los procesos ecológicos que en la actualidad afectan a esta especie. Usando la información recopilada mediante el seguimiento de 442 batidas durante ocho temporadas de caza en los Pirineos (Urdués, norte de España), se analizaron cuestiones relacionadas con la variabilidad local de la abundancia de jabalí. Los resultados revelaron oscilaciones temporales de la abundancia y una disminución discontinua del 23% en el número de jabalíes avistados por batida entre 2004 y 2011. El número de perros y de cazadores por batida también afectó a los índices de abundancia de jabalí. Las variaciones interanuales de animales abatidos pueden provocar que se sobreestimen las variaciones de la abundancia de jabalí e incluso pueden desviarse de la dinámica de poblaciones inferida del número de jabalíes avistados por batida. En los Pirineos, el patrón multimodal de la abundancia de jabalí durante las temporadas de caza sugiere la existencia de movimientos migratorios. Los resultados obtenidos destacan las limitaciones de las estadísticas de abundancia realizadas sobre el número de jabalíes abatidos y ponen de manifiesto la necesidad de llevar a cabo nuevos estudios que permitan gestionar las poblaciones de jabalí de forma sostenible y fundamentada
River flows in the Ebro basin: A century of evolution, 1913-2013
The water forecast is a major uncertainty in the design of strategies to cope with potential restrictions and ensure the availability of water, even during extreme events such as drought. In this context, our study aimed to present and analyze an updated broad temporal and geographical overview of the evolution of river flows for the most important river in Spain, the Ebro river, from 1913 to 2013. Our main findings indicate a decreasing trend in water resources from 1913 to the present, and a significant level of volatility that reveals a striking irregularity, with asymmetric cycles and dry years. These findings question the current irrigation policies and together with a need to rethink their implementation should drive further researc
Environmental flow management: an analysis applied to the Ebro River Basin
Environmental flows (EF) define the quantity, timing and quality of river flows needed to preserve freshwater ecosystems while assuring the continuity of human use. Insofar as they reduce water availability and condition agricultural and industrial uses, EF represent a constraint, but they also hold out new opportunities for development. This study focuses on the final stretch of the Ebro River (Spain) and on the competing environmental uses of water (the Ebro Delta is a biosphere reserve) and economic uses (irrigation and electricity generating). Environmental flows in the Ebro Delta are currently managed only from the Mequinenza dam and reservoir in eastern Aragon, and the resulting outflows have more than once driven the level of the reservoir down to critical environmental levels in recent years. In general, this management policy has also caused a range of negative environmental and economic impacts in the area. However, other alternatives exist, which could foster both more cooperative and equitable flow allocations, and the development and sustainability of the Ebro Basin. To this end, we develop a water management model to simulate scarcity scenarios and measure the associated environmental flow default rates assuming current productive uses. Our findings confirm that it is not possible to guarantee EFs in the delta without reservoir-based water management so as to ensure the compatibility of EFs with the irrigation and hydroelectric activities. Moreover, the existence of more equitable and cooperative water management options would reduce water pressures on Mequinenza dam and so help fulfill the subsidized irrigation commitments established in Aragonese Lower Ebro Plan
Glutamate transporter dysfunction associated with nerve injury-induced pain in mice
Dysfunction at glutamatergic synapses has been proposed as a mechanism in the development of neuropathic pain. Here we sought to determine whether peripheral nerve injury-induced neuropathic pain results in functional changes to primary afferent synapses. Signs of neuropathic pain as well as an induction of glial fibrillary acidic protein in immunostained spinal cord sections 4 days after partial ligation of the sciatic nerve indicated the induction of neuropathic pain. We found that following nerve injury, no discernable change to kinetics of dl-α-amino-3-hydroxy-5-methylisoxazole-propionic acid (AMPA) or N-methyl-d-aspartate receptor (NMDAR)-mediated evoked excitatory postsynaptic currents (eEPSCs) could be observed in dorsal horn (lamina I/II) neurons compared with those of naïve mice. However, we did find that nerve injury was accompanied by slowed decay of the early phase of eEPSCs in the presence of glutamate transporter inhibition by the competitive nontransportable inhibitor dl-threo-β-benzyloxyaspartic acid (TBOA). Concomitantly, expression patterns for the two major glutamate transporters in the spinal cord, excitatory amino acid transporters (EAAT) 1 and EAAT2, were found to be reduced at this time (4 days postinjury). We then sought to directly determine whether nerve injury results in glutamate spillover to NMDARs at dorsal horn synapses. By employing the use-dependent NMDAR blocker (±)MK-801 to block subsynaptic receptors, we found that although TBOA-induced spillover to extrasynaptic receptors trended to increased activation of these receptors after nerve injury, this was not significant compared with naïve mice. Together, these results suggest the development of neuropathic pain involves subtle changes to glutamate transporter expression and function that could contribute to neuropathic pain during excessive synaptic activity.NHMRC grant: 0569927 & 35144
Influence of the material composition SMD diodes on their environmental impact
The influence of the material composition of surface-mount device (SMD) diodes on the environment has been analysed in this research. This impact assessment has been performed by means of an environmental impact calculation through a life cycle assessment (LCA), in which the EcoInvent dataset has been updated and customised, generating a more precise environmental impact analysis by considering the exact material composition provided by several suppliers of diodes and also recycling during the production stage. Considering the EcoInvent diode dataset as a reference, variations from nearly 1640% to only 8.5% of the environmental impact have been achieved. For example, the impact per 1 g of SMD diodes can change the global warming potential from 292 g CO2 eq up to 354 g CO2 eq, whereas for abiotic depletion, values can change from 9.9 × 10-7 up to 1.9 × 10-4 kg Sb eq. The presence of critical raw materials such as antimony, cobalt, or magnesium, together with precious metals as gold or silver, highly influences the environmental impact values obtained, demonstrating the considerable influence on the environmental impact of the material composition of the SMD diodes analysed. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Study of evolution of microbiological properties in sewage sludge-amended soils: A pilot experience
Large amounts of sewage sludge are generated in urban wastewater treatment plants and used as fertilizer in agriculture due to its characteristics. They can contain contaminants such as heavy metals and pathogenic microorganisms. The objective of this research work is to study, in real conditions, the evolution of microbial concentration in agricultural soils fertilized by biologically treated sewage sludge. The sludge (6.25 tons Ha-1 ) was applied in two agricultural soils with different textures and crops. A microbiological (total coliforms, Escherichia coli, Staphylococcus aureus, Enterococcus sp., Pseudomonas sp., Salmonella sp. and total mesophylls) and physical-chemical characterization of the sludge, soils and irrigation water were carried out. The evolution of these parameters during sowing, growth and harvesting of crops was studied. Initially, sewage sludge had a higher concentration of microorganisms than soils. Irrigation water also contained microorganisms, fewer than sewage sludge amendment but not negligible. After amendment, there were no differences in the microbiological evolution in the two types of soil. In general, bacterial concentrations after crop harvest were lower than bacterial concentrations detected before sewage sludge amendment. Consequently, the application of sludge from water treatment processes did not worsen the microbiological quality of agricultural soil in this study at real conditions
Polymorphisms in the MTHFR gene influence embryo viability and the incidence of aneuploidy
MTHFR is an important enzyme in the metabolism of folic acid and is crucial for reproductive function. Variation in the sequence of MTHFR has been implicated in subfertility, but definitive data are lacking. In the present study, a detailed analysis of two common MTHFR polymorphisms (c.677C>T and c.1298A>C) was performed. Additionally, for the first time, the frequencies of different MTHFR alleles were assessed in preimplantation embryos. Several striking discoveries were made. Firstly, results demonstrated that maternal MTHFR c.1298A>C genotype strongly influences the likelihood of a pregnancy occurring, with the 1298C allele being significantly overrepresented amongst women who have undergone several unsuccessful assisted reproductive treatments. Secondly, parental MTHFR genotypes were shown to affect the production of aneuploid embryos, indicating that MTHFR is one of the few known human genes with the capacity to modulate rates of chromosome abnormality. Thirdly, an unusual deviation from Hardy-Weinberg equilibrium was noted for the c.677C>T polymorphism in subfertile patients, especially those who had experienced recurrent failure of embryo implantation or miscarriage, potentially explained by a rare case of heterozygote disadvantage. Finally, a dramatic impact of the MTHFR 677T allele on the capacity of chromosomally normal embryos to implant is described. Not only do these findings raise a series of interesting biological questions, but they also argue that testing of MTHFR could be of great clinical value, identifying patients at high risk of implantation failure and revealing the most viable embryos during in vitro fertilisation (IVF) cycles
Europeanization vs. Globalization? A deeper look into income and employment embodied in intra-European trade
Production processes are nowadays increasingly global, implying interdependent structures linking goods, processes and countries. Traditional economic blocks and sectoral intra-country linkages coexist with increasing worldwide dependencies. Recent literature supports the hypothesis of a new globalization process taking place in the late 1990s and the 21st century, centred on the consolidation of increasingly competitive macro-regions at a global level, with a growing specialization of countries within them. We propose a multiregional input-output (MRIO) model of the European Union (EU) to analyse whether the generation of employment and income in Europe in recent decades can be defined as a process that is mainly regional or global (involving countries within the region versus countries outside Europe). Our results show that intra-EU trade is an important factor contributing to income and employment growth, more oriented to intermediate inputs, in the same way as extra-EU trade, despite the fact that some European countries are more specialized in final goods, mainly driven by high-income EU countries.
Los procesos de producción son hoy en día cada vez más globales, lo que implica estructuras interdependientes que vinculan bienes, procesos y países. Los bloques económicos tradicionales y los vínculos sectoriales dentro del país coexisten con dependencias mundiales crecientes. La literatura reciente respalda la hipótesis de un nuevo proceso de globalización que tuvo lugar a fines de los años 90 y el siglo XXI, centrado en la consolidación de macro-regiones cada vez más competitivas a nivel global, con una creciente especialización de los países dentro de ellas. Proponemos un modelo multirregional input-output (MRIO) de la Unión Europea (UE) para analizar si la generación de empleo e ingresos en Europa en las últimas décadas se puede definir como un proceso que es principalmente regional o global. Nuestros resultados muestran que el comercio intracomunitario es un factor importante que contribuye al crecimiento de los ingresos y el empleo, más orientado a los inputs intermedios, de la misma manera que el comercio extracomunitario, a pesar del hecho de que algunos países europeos están más especializados en productos finales, principalmente demandados por países de altos ingresos de la UE
Contributions on lindane degradation by Microcystis aeruginosa PCC 7806
Cyanobacteria are able to tolerate, and even metabolize, moderate doses of organochlorine pesticides, such as lindane (¿-hexachlorocyclohexane), one of the most persistent and widely used in recent decades. Previous work showed that Microcystis aeruginosa PCC 7806 degrades lindane and that, in the presence of the pesticide, microcystin synthesis is enhanced. In this work, using in silico approaches, we have identified in M. aeruginosa putative homologues of the lin genes, involved in lindane degradation in Sphingobium japonicum UT26S. Real-time RT-PCR assays showed that the putative linC gene was induced in the presence of 7 mg/L of lindane. Additionally, prxA, encoding a peroxiredoxin, and involved in oxidative stress response, was also induced when lindane was present. Taking into account these results, M. aeruginosa PCC 7806 may degrade lindane through a metabolic pathway involving a putative 2, 5-dichloro-2, 5-cyclohexadiene-1, 4-diol dehydrogenase encoded by a linC homologue. However, the low similarity of the other potential lin homologues suggest the existence of an alternative pathway different to that of heterotrophic microorganisms such as S. japonicum
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