133 research outputs found

    Contribución al conocimiento de crustáceos y rotíferos del Delta del Ebro

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    Weed abundance is positively correlated with native plant diversity in grasslands of southern Australia

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    Published: June 1, 2017Weeds are commonly considered a threat to biodiversity, yet interactions between native and exotic species in grasslands are poorly understood and reported results vary depending on the spatial scale of study, the factors controlled for and the response variables analysed. We tested whether weed presence and abundance is related to declines in biodiversity in Australian grasslands. We employed existing field data from 241 plots along a disturbance gradient and correlated species richness, cover and Shannon diversity for natives and exot- ics, controlling for seasonal rainfall, climatic gradients and nutrient status. We found no neg- ative relationships in terms of emergent diversity metrics and occupation of space, indeed, many positive relationships were revealed. When split by land-use, differences were found along the disturbance gradient. In high-moderately disturbed grasslands associated with land-uses such as cropping and modified pastures, positive associations were enhanced. Tolerance and facilitation mechanisms may be involved, such as complementary roles through different life history strategies: the exotic flora was dominated mainly by annual grasses and herbs whereas the native flora represented more diverse growth-forms with a higher proportion of perennials. The positive relationships existing between native and exotic plant species in high-moderately disturbed grasslands of South Australia are most likely due to facilitation through different strategies in occupation of space given that the effect of habitat suitability was controlled for by including environmental and disturbance fac- tors. Consequently, although particular weeds may negatively impact biodiversity, this can- not be generalised and management focusing on general weed eradication in grasslands might be ineffectual.Irene Martín-Forés, Greg R. Guerin, Andrew J. Low

    Superando el concepto de nativo digital. Análisis de las prácticas digitales del estudiantado universitario

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    A lo largo de la última década, niños y jóvenes han sido etiquetados como nativos digitales. Se considera que cualquier persona nacida a partir de la década de los 80 es hablante nativo de una lengua digital basada en el uso de los ordenadores, los videojuegos e Internet. De todos modos, algunos autores cuestionan este concepto ¿se trata realmente de jóvenes que aprenden de modo distinto, o simplemente incorporan algunas herramientas y procedimientos nuevos a su forma de acceder a la información y socializarse? El artículo presenta los resultados de una investigación (Usos de las TIC entre los estudiantes universitarios: perspectiva académica y social de los procesos de aprendizaje mediados. EDU2009-12125) centrada en el uso de las TIC que hacen los jóvenes universitarios de las diferentes universidades de Cataluña. Los resultados revelan distintos usos de las tecnologías, diferenciados por los ámbitos de uso y se alinean en las visiones críticas del concepto de nativo digital. La relevancia de los resultados apuntan a lineas emergentes de investigación para seguir mejorando la educación superior

    EGFR/Ras Signaling Controls Drosophila Intestinal Stem Cell Proliferation via Capicua-Regulated Genes

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    Epithelial renewal in the Drosophila intestine is orchestrated by Intestinal Stem Cells (ISCs). Following damage or stress the intestinal epithelium produces ligands that activate the epidermal growth factor receptor (EGFR) in ISCs. This promotes their growth and division and, thereby, epithelial regeneration. Here we demonstrate that the HMG-box transcriptional repressor, Capicua (Cic), mediates these functions of EGFR signaling. Depleting Cic in ISCs activated them for division, whereas overexpressed Cic inhibited ISC proliferation and midgut regeneration. Epistasis tests showed that Cic acted as an essential downstream effector of EGFR/Ras signaling, and immunofluorescence showed that Cic’s nuclear localization was regulated by EGFR signaling. ISC-specific mRNA expression profiling and DNA binding mapping using DamID indicated that Cic represses cell proliferation via direct targets including string (Cdc25), Cyclin E, and the ETS domain transcription factors Ets21C and Pointed (pnt). pnt was required for ISC over-proliferation following Cic depletion, and ectopic pnt restored ISC proliferation even in the presence of overexpressed dominant-active Cic. These studies identify Cic, Pnt, and Ets21C as critical downstream effectors of EGFR signaling in Drosophila ISCs.This work was supported by the DKFZ, DFG grant SFB 873, and ERC Advanced Grant 268515 to BAE. NH was supported by SFB638, SFB1036. MF and GJ were supported by research grants from the Spanish Government (BFU2011-23611) and Fundació La Marató de TV3 (20131730); GJ is an ICREA investigatorPeer Reviewe

    Invertebrados continentales de las Islas Columbretes. Nuevas especies

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    The terrestrial invertebrate fauna of the protected archipelago of Columbretes is poorly known. Moreover, the few existing studies are centered on its main island, Illa Grossa. Herein we present the list of invertebrate species not cited so far in the archipelago, results of a combination of pitfall trap catches, direct visual observations, and random collections performed in Illa Grossa as well as in three additional islets of this archipelago. The first method resulted in 14.830 specimens collected from 2008-2011. The highest number of individuals collected by this method were tenebrionid beetles. The other two methods provided 514 records for the period 2004-2013. In total, 45 new records corresponding to 40 genera in 16 families were identified. Most of the new species could not be regularly found during the whole sampling period. Some typical of anthropogenic habitats species were found (i.e., Cydnus aterrimus, Gryllus bimaculatus). Remarkably, some species with limited dispersal abilities and not common in small islands (i.e., Cebrio superbus) have been found.La fauna terrestre de invertebrados del archipiélago protegido de Columbretes es poco conocida. Además, los pocos estudios existentes se centran en su isla principal, Illa Grossa. Aquí presentamos el listado de especies de invertebrados no registradas, hasta el momento, en el archipiélago, resultados obtenidos mediante una combinación de capturas con trampas de caída, avistamientos y recolecciones aleatorias realizadas tanto en Illa Grossa como en otros tres islotes de este archipiélago. Mediante el primer método se recolectaron un total de 14.830 especímenes entre 2008-2011. La mayor cantidad de individuos recolectados mediante este método resultaron ser coleópteros tenebriónidos. Los otros dos métodos proporcionaron 514 registros para el período 2004-2013. En total, se han identificado 45 nuevos taxones correspondientes a 40 géneros y 16 familias. La mayoría de las nuevas especies encontradas no fueron frecuentes a lo largo del período de muestreo. Entre ellas, figuran especies típicas de hábitats antrópicos (p.e. Cydnus aterrimus o Gryllus bimaculatus). Sorprendentemente, también se localizaron en ocasiones especies con capacidades de dispersión limitadas y no presentes en islas pequeñas (p.e. Cebrio superbus)

    La conservación de biodiversidad en España: atención científica, construcción social e interés político

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    El presente trabajo explora los factores que subyacen a la priorización de especies en las políticas de conservación de la biodiversidad en relación con las diferentes dimensiones implicadas: investigación, opinión pública, listas rojas y legislación vinculante de especies amenazadas. Los resultados muestran que existe una fuerte correlación entre las especies prioritarias de conservación, aquellas que son objeto de interés científico, así como las preferidas socialmente. De hecho, parece existir un bucle de realimentación positiva que actúa como una trampa de conservación en la priorización de especies, en la que muy pocas especies se convierten en objeto de protección, relegando a otras que tienen un importante papel funcional en distintos tipos de ecosistemas, con singularidad taxonómica, o elevada posibilidad de éxito en su conservación. Finalmente, se identifica cuáles son los grupos taxonómicos aventajados en el actual sistema de toma de decisiones relativo a la conservación, y cuáles parecen ser invisibles

    Anorexia nervosa and cancer: a protocol for a systematic review and meta-analysis of observational studies

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    This is the final version of the article. Available from the publisher via the DOI in this record.BACKGROUND: Anorexia nervosa is characterized by a severe restriction of caloric intake, low body weight, fear of gaining weight or of becoming fat, and disturbance of body image. Pathogenesis of the disorder may include genetic predisposition, hormonal changes and a combination of environmental, psychosocial, and cultural factors. Cancer is the second leading cause of death worldwide. At present, no systematic reviews and meta-analyses have evaluated the risk of cancer in people with anorexia nervosa. The objective of this study will be to evaluate the association between anorexia nervosa and the risk of developing or dying from cancer. METHODS/DESIGN: This study protocol is part of a systematic collection and assessment of multiple systematic reviews and meta-analyses (umbrella review) evaluating the association of cancer and multiple central nervous system disorders. We designed a specific protocol for a new systematic review and meta-analysis of observational studies of anorexia nervosa with risk of developing or dying from any cancer. Data sources will be PubMed, Embase, Scopus, Web of Science, and manual screening of references. Observational studies (case-control and cohort) in humans that examined the association between anorexia nervosa and risk of developing or dying from cancer will be sought. The primary outcomes will be cancer incidence and cancer mortality in association with anorexia nervosa. Secondary outcomes will be site-specific cancer incidence and mortality, respectively. Screening of abstracts and full texts, and data abstraction will be performed by two team members independently. Conflicts at all levels of screening and abstraction will be resolved through discussion. The quality of studies will be assessed by using the Ottawa-Newcastle scale by two team members independently. Random effects models will be conducted where appropriate. Subgroup and additional analyses will be conducted to explore the potential sources of heterogeneity. The World Cancer Research Fund (WCRF)/American Institute for Cancer Research (AICR) criteria and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach will be used for determining the quality of evidence for cancer outcomes. DISCUSSION: Findings from this systematic review will inform an ongoing umbrella review on cancer and central nervous system disorders. Our systematic review and meta-analysis of observational studies will establish the extent of the epidemiological evidence underlying the association between anorexia nervosa and cancer. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42017067462.Specific funding from the Generalitat Valenciana (PROMETEOII/2015/021) and CIBERSAM/Institute of Health Carlos III was received for this work. The funders were not involved in the design of the protocol or decision to submit the protocol for publication, nor will they be involved in any aspect of the conduct of the review. BH is supported by a New Investigator Award from the Canadian Institutes of Health Research and the Drug Safety and Effectiveness Network. MR is partially funded by the Spanish Health Services Research on Chronic Patients Network (REDISSEC)/Institute of Health Carlos III. The views expressed in this article are the views of the authors and may not be understood or quoted as being made on behalf of, or reflecting the position of, the funder(s) or any institution

    Circulating miRNA Fingerprint and Endothelial Function in Myocardial Infarction : Comparison at Acute Event and One-Year Follow-Up

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    MicroRNAs (miRNA) are major regulators of intercellular communication and key players in the pathophysiology of cardiovascular disease. This study aimed to determine the miRNA fingerprint in a cohort of 53 patients with acute myocardial infarction (AMI) with non-ST-segment elevation (NSTEMI) relative to miRNA expression in healthy controls (n = 51). miRNA expression was initially profiled by miRNA array in the serum of patients undergoing cardiac catheterization during NSTEMI (n = 8) and 1 year past the event (follow-up, n = 8) and validated in the entire cohort. In total, 58 miRNAs were differentially expressed during AMI (p < 0.05), while 36 were modified at follow-up (Fisher's exact test: p = 0.0138). Enrichment analyses revealed differential regulation of biological processes by miRNA at each specific time point (AMI vs. follow-up). During AMI, the miRNA profile was associated mainly with processes involved in vascular development. However, 1 year after AMI, changes in miRNA expression were partially related to the regulation of cardiac tissue morphogenesis. Linear correlation analysis of miRNA with serum levels of cytokines and chemokines revealed that let-7g-5p, let-7e-5p, and miR-26a-5p expression was inversely associated with serum levels of pro-inflammatory cytokines TNF- , and the chemokines MCP-3 and MDC. Transient transfection of human endothelial cells (HUVEC) with let-7e-5p inhibitor or mimic demonstrated a key role for this miRNA in endothelial function regulation in terms of cell adhesion and angiogenesis capacity. HUVEC transfected with let-7e-5p mimic showed a 20% increase in adhesion capacity, whereas transfection with let-7e-5p inhibitor increased the number of tube-like structures. This study pinpoints circulating miRNA expression fingerprint in NSTEMI patients, specific to the acute event and changes at 1-year follow-up. Additionally, given its involvement in modulating endothelial cell function and vascularization, altered let-7e-5p expression may constitute a therapeutic biomarker and target for ischemic heart disease

    Stakeholder influence on teaming and absorptive capacity in innovation networks

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    Through technological developments, innovation increasingly occurs within a network of organizations such as Industry 4.0 fieldlabs. As a result, collaboration between different companies and institutions with different interests needs to take place. Three Dutch smart industry fieldlabs were analysed to study how these collaborative relationships are being established and what their impact is on the absorptive capacity of the network in question. Contrary to what was expected, we found that stakeholders hardly exercised power. Also, a high level of psychological safety was found in the network, which positively affects collaboration. Furthermore, collaborative elements—such as open conversation, collaborating, experimenting and reflecting—are important factors affecting the absorptive capacity in the fieldlabs examined. The article concludes with several practical implications on how to stimulate innovation capability
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