Frugivoría y dispersión de semillas por mamíferos carnívoros: rasgos funcionales

Muchas especies de mamíferos carnívoros (Orden Carnivora) consumen frutos carnosos, transportan semillas en sus tractos digestivos y las defecan sin dañarlas en condiciones apropiadas para la germinación. En este artículo, revisamos el conocimiento adquirido sobre este mutualismo en las últimas tres décadas, desde que tres trabajos pioneros revelaron la importancia de los carnívoros como dispersores de semillas en ecosistemas templados. Nos centramos en los rasgos funcionales de los carnívoros consumiendo frutos y diseminando semillas, haciendo especial énfasis en sus diferencias con las aves, el principal grupo de vertebrados frugívoros en ecosistemas templados. Los carnívoros no están sujetos a las restricciones fenológicas o morfológicas que típicamente limitan el consumo de determinados frutos en muchas especies de aves. Consumen preferentemente frutos cuyos atributos son compartidos con muchas especies de frutos cultivados por el hombre, lo que explica el consumo frecuente de éstos en paisajes antrópicos. Sus amplios requerimientos espaciales favorecen la dispersión de semillas a larga distancia, mientras que su generalismo en relación al hábitat favorece el flujo de semillas entre hábitats contrastados. De este modo, los carnívoros promueven la conectividad entre poblaciones vegetales y la colonización. Estas funciones ecológicas son clave para las comunidades vegetales nativas, especialmente en escenarios de cambios de uso de suelo. Sin embargo, estos patrones de dispersión de semillas pueden contribuir a la invasión de plantas exóticas. Aún ignoramos en gran medida el papel de los carnívoros en términos cuantitativos de la dispersión de semillas y las diferencias funcionales entre especies dentro del gremio. La integración de muestreos clásicos e innovadoras técnicas moleculares y de análisis espacial promete aportar conocimiento inédito en estas cuestiones[EN ] Many species of carnivorous mammals (Order Carnivora) consume fleshy fruits, transport seeds in their digestive tracts, and defecate them without damage in conditions that are suitable for germination. In this article, we review the state of the art on this mutualism in the past three decades, since three pioneering studies revealed the importance of carnivores as seed dispersers in temperate ecosystems. We focus on the functional traits of carnivores consuming fruits and disseminating seeds, with particular emphasis on their differences with birds, the main group of vertebrate frugivores in temperate ecosystems. Carnivores are not subject to the phenological or morphological constraints that typically limit the consumption of certain fruit species in many bird species. They preferably consume fruits whose traits are shared with many fruit species cultivated by man, which explains the frequent consumption of cultivated fruits in anthropogenic landscapes. The large spatial requirements of carnivores promote long-distance seed dispersal, while their habitat generalism promotes seed flows between contrasting habitats. Thus, carnivores promote connectivity between plant populations and colonization. These are key ecological functions for native plant communities, especially in scenarios of land-use changes. However, these seed dispersal patterns can contribute to the invasion of exotic plants. We still largely ignore the role of carnivores in quantitative terms of seed dispersal and the functional differences between species within the guild. Integrating traditional fieldwork and innovative molecular techniques and spatial analysis promises to provide unprecedented knowledge on these issuesPeer reviewe

New Omnidirectional Sensor Based on Open-Source Software and Hardware for Tracking and Backtracking of Dual-Axis Solar Trackers in Photovoltaic Plants

In this work, an omnidirectional sensor that enables identification of the direction of the celestial sphere with maximum solar irradiance is presented. The sensor, based on instantaneous measurements, functions as a position server for dual-axis solar trackers in photovoltaic plants. The proposed device has been developed with free software and hardware, which makes it a pioneering solution because it is open and accessible as well as capable of being improved by the scientific community, thereby contributing to the rapid advancement of technology. In addition, the device includes an algorithm developed ex professo that makes it possible to predetermine the regions of the celestial sphere for which, according to the geometric characteristics of the PV plant, there would be shading between the panels. In this way, solar trackers do not have to locate the Sun’s position at all times according to astronomical models, while taking into account factors such as shadows or cloudiness that also affect levels of incident irradiance on solar collectors. Therefore, with this device, it is possible to provide photovoltaic plants with dual-axis solar tracking with a low-cost device that helps to optimise the trajectory of the trackers and, consequently, their radiative capture and energy production

Distribution and determinants of sedentary lifestyles in the European Union

Background Many studies have shown the health burden of a sedentary lifestyle. The main goal of this study was to determine the prevalence of sedentary lifestyles in the 15 Member States of the European Union (EU) and to identify the main correlates of a sedentary lifestyle. Methods Nationally representative samples (n ≈ 1000 subjects in each country; >15 years) completed a questionnaire concerning attitudes to physical activity, body weight, and health; in total 15 239 subjects. Sedentary people were defined in two ways: (1) those expending less than 10% of their leisure time expenditure in activities involving ≥4 metabolic equivalents (MET). (2) Those who did not practice any leisure-time physical activity and who also were above the median in the number of hours spent sitting down during leisure time. Logistic regression models were fitted to analyse the association between sedentary lifestyles and gender, age, body mass index (BMI), educational level, weight change in the last 6 months, and marital and smoking status. Results Percentages of sedentary lifestyles across European countries ranged between 43.3% (Sweden) and 87.8% (Portugal) according to the first definition. According to both definitions, a lower prevalence of sedentary lifestyle was found in Northern countries (especially Scandinavian countries) as compared with Mediterranean countries, whereas the prevalence was higher among older, obese, less educated, widowed/divorced individuals, and current smokers. Similar relative differences between countries and socio-demographic groups were found independently of the method used to define a sedentary lifestyle. Conclusion Prevalence of sedentary lifestyle in the EU is high, especially among inhabitants of some Mediterranean countries, obese subjects, less-educated people, and current smokers. This high prevalence involves important public health burdens and preventive strategies are urgently needed

Prevalence of physical activity during leisure time in the European Union

PURPOSE: To estimate the prevalence of physical activity during leisure time in adults from the 15 member states of the European Union and the relationship with sociodemographic variables. METHODS: A representative sample, with approximately 1000 adults, aged 15 and upward, was selected from each member state to complete a questionnaire on attitudes to physical activity, body weight, and health by a face-to-face interview, summing a total of 15,239 subjects. The amount of leisure-time physical activity was quantified by assigning metabolic equivalents (METs) to each activity. Multiple linear regression models with MET-h.wk(-1) as the dependent variable were fitted. RESULTS: Northern European countries showed higher levels of physical activity than southern ones. The highest prevalence (91.9%) was found in Finland, and the lowest (40.7%) in Portugal. A higher percentage of men practiced any leisure-time physical activity and also showed higher mean of MET-h.wk(-1). In both genders, the multivariate models showed a significant trend to higher leisure time activity in participants with higher educational levels and in nonsmokers. Also, an inverse association between body mass index and leisure-time physical activity was found. CONCLUSION: The prevalence of any physical activity during leisure time in the adult European population was similar to the U.S. estimates. Nevertheless, the amount of activity is low, and a wide disparity between countries exists. To our knowledge, this is the first study determining the prevalence and amount of leisure-time physical activity, which is the first step to define strategies to persuade populations to increase their physical activity

Benchmarking Analysis of the Panorama of Grid-Connected PV Installations in Spain

Renewable energies play an important role as a solution to the challenge of satisfying the growing global energy demand without jeopardizing the achievements in the fight against climate change. Given this panorama, different countries, including Spain, have developed policies to promote renewable energies. One of the technologies that benefit from these policies is photovoltaics. In Spain, the number of grid-connected photovoltaic installations has increased significantly in recent years. It is interesting to analyze the panorama of these facilities and identify the trends in their design criteria. In this line, in this work, the projects of 70 grid-connected photovoltaic installations distributed across Spain were analyzed. For that purpose, benchmarking techniques were applied, facilitating the systematization of information, the intercomparison of plants and the identification of trends and efficient solutions. A set of characteristic indicators of each installation was defined, and a statistical analysis of them was developed. Likewise, a tool was developed that allows the designers of this type of photovoltaic plant to compare the design parameters chosen for their installations with those of the surrounding area. Therefore, this work provides knowledge about the current panorama of photovoltaic implementation applicable to its future advan

Genetic studies in sunflower broomrape

Much research has been conducted to identify sources of genetic resistance to sunflower broomrape (Orobanche cumana Wallr.) and to study their mode of inheritance. However, studies on the parasite have been scarce. This manuscript reviews three genetic studies in sunflower broomrape. First, the inheritance of the absence of pigmentation in a natural mutant of this species with yellow plant color phenotype was studied. In a first stage, lines from the unpigmented mutant and a normally pigmented population were developed by several generations of self-pollination. Plants of both lines were crossed and the F1, F2, and F3 generations were evaluated. The results indicated that plant pigmentation is controlled by a partially dominant allele at a single locus. Second, the unpigmented mutant was used to evaluate outcrossing potential of the species. Two experiments in which single unpigmented plants were surrounded by normally pigmented plants were conducted under pot and field conditions. The cross-fertilization rate was estimated as the percentage of F1 hybrids in the progenies of unpigmented plants, which averaged 21.5% in the pot and 28.8% in the field experiment. The results indicated that, under the conditions of this study, the species was not strictly self-pollinated. Finally, the inheritance of avirulence was studied in crosses of plants from lines of O. cumana races E and F, developed by several generations of self-pollination. The F1 and F3 generations were evaluated on the differential line P-1380 carrying the race-E resistance gene Or5. The results suggested that race E avirulence and race F virulence on P-1380 are allelic and controlled by a single locus, which confirmed the gene-for-gene theory for the O. cumana-sunflower interaction.The manuscript reviews research partially funded by Fundación Ramón Areces, Madrid. The contribution of Dr. Enrique Quesada Moraga, entomologist from the University of Córdoba, Spain, to taxonomic classification of pollinators is gratefully acknowledged. R. Pineda-Martos was the recipient of a PhD fellowship from the Spanish National Research Council (CSIC) (JAEPre_08_00370)Peer Reviewe

Association between serum soluble CD40 ligand levels and mortality in patients with severe sepsis

INTRODUCTION: CD40 Ligand (CD40L) and its soluble counterpart (sCD40L) are proteins that exhibit prothrombotic and proinflammatory properties on binding to their cell surface receptor CD40. The results of small clinical studies suggest that sCD40L levels could play a role in sepsis; however, there are no data on the association between sCD40L levels and mortality of septic patients. Thus, the aim of this study was to determine whether circulating sCD40L levels could be a marker of adverse outcome in a large cohort of patients with severe sepsis. METHODS: This was a multicenter, observational and prospective study carried out in six Spanish intensive care units. Serum levels of sCD40L, tumour necrosis factor-alpha and interleukin-10, and plasma levels of tissue factor were measured in 186 patients with severe sepsis at the time of diagnosis. Serum sCD40L was also measured in 50 age- and sex-matched controls. Survival at 30 days was used as the endpoint. RESULTS: Circulating sCD40L levels were significantly higher in septic patients than in controls (P = 0.01), and in non-survivors (n = 62) compared to survivors (n = 124) (P = 0.04). However, the levels of CD40L were not different regarding sepsis severity. Logistic regression analysis showed that sCD40L levels >3.5 ng/mL were associated with higher mortality at 30 days (odds ratio = 2.89; 95% confidence interval = 1.37 to 6.07; P = 0.005). The area under the curve of sCD40L levels >3.5 ng/mL as predictor of mortality at 30 days was 0.58 (95% CI = 0.51 to 0.65; P = 0.03). CONCLUSIONS: In conclusion, circulating sCD40L levels are increased in septic patients and are independently associated with mortality in these patients; thus, its modulation could represent an attractive therapeutic target

Glutaminase and MMP-9 downregulation in cortex and hippocampus of LPA1 receptor null mice correlate with altered dendritic spine plasticity

Lysophosphatidic acid (LPA) is an extracellular lipid mediator that regulates nervous system development and functions acting through G protein-coupled receptors (GPCRs). Here we explore the crosstalk between LPA1 receptor and glutamatergic transmission by examining expression of glutaminase (GA) isoforms in different brain areas isolated from wild-type (WT) and KOLPA1 mice. Silencing of LPA1 receptor induced a severe down-regulation of Gls-encoded long glutaminase protein variant (KGA) (glutaminase gene encoding the kidney-type isoforms, GLS) protein expression in several brain regions, particularly in brain cortex and hippocampus. Immunohistochemical assessment of protein levels for the second type of glutaminase (GA) isoform, glutaminase gene encoding the liver-type isoforms (GLS2), did not detect substantial differences with regard to WT animals. The regional mRNA levels of GLS were determined by real time RT-PCR and did not show significant variations, except for prefrontal and motor cortex values which clearly diminished in KO mice. Total GA activity was also significantly reduced in prefrontal and motor cortex, but remained essentially unchanged in the hippocampus and rest of brain regions examined, suggesting activation of genetic compensatory mechanisms and/or post-translational modifications to compensate for KGA protein deficit. Remarkably, Golgi staining of hippocampal regions showed an altered morphology of glutamatergic pyramidal cells dendritic spines towards a less mature filopodia-like phenotype, as compared with WT littermates. This structural change correlated with a strong decrease of active matrix-metalloproteinase (MMP) 9 in cerebral cortex and hippocampus of KOLPA1 mice. Taken together, these results demonstrate that LPA signaling through LPA1 influence expression of the main isoenzyme of glutamate biosynthesis with strong repercussions on dendritic spines maturation, which may partially explain the cognitive and learning defects previously reported for this colony of KOLPA1 mice