Dissecting the assembly process of benthic communities from neotropical streams

§ La conservación y rehabilitación de la estructura y funcionamiento de los ecosistemas requiere de un conocimiento profundo de las causas y consecuencias de su biodiversidad. Sin embargo, este conocimiento es aún escaso en regiones Neotropicales. § En esta tesis, utilizo el marco conceptual de las metacomunidades para caracterizar los posibles efectos que tienen los procesos de dispersión (en tiempos ecológicos y evolutivos), selección (impulsada por factores abióticos) y deriva ecológica en la diversidad y distribución de las comunidades bentónicas fluviales. 2 § La zona de estudio, de un área de aproximadamente 40,000 km , abarcó entre 26 y 32 segmentos de ríos prístinos del Orinoco colombiano. Los puntos de muestreo abarcaron un gradiente de elevación de 300 a 3400 m.s.n.m. que incluyó un conjunto heterogéneo de ecorregiones y paisajes. § Mediante una aproximación de ligar patrones y posibles mecanismos, esta tesis proporciona evidencias de que la dispersión, la selección y la deriva están directamente involucradas en el proceso de ensamblaje de las comunidades bentónicas fluviales. § Mis hallazgos indican que uno o más eventos de limitación de la dispersión en un marco de tiempo evolutivo (eventos de aislamiento alopátrico) formaron diferentes pools de especies dentro de la cuenca del Orinoco. La extensión de estos pools coincide parcialmente con la distribución de las ecorregiones, lo que sugiere que los eventos que moldearon los paisajes fluviales y la estructura de la vegetación afectaron de manera similar la diversidad y distribución de las especies bentónicas en ecosistemas fluviales. § Adicionalmente, dentro de cada ecorregión, la dispersión, la selección y la deriva están interactuando para restringir la estructura y la dinámica de las comunidades y metacomunidades entre y dentro de los ríos. Dependiendo de la comunidad (p.e. diatomeas o insectos), el papel de cada uno de estos procesos puede prevalecer sobre el de los demás. § Estos hallazgos tienen implicaciones tanto para la investigación básica como para la aplicada (p.e. biomonitoreo) en las disciplinas de la ecología de metacomunidades y de agua dulce, así como en la conservación y la biogeografía.§ The conservation and rehabilitation of ecosystem structure and functioning requires of a deep knowledge on the causes and consequences of its biodiversity. The assembly of Neotropical communities, particularly in riverine ecosystems, remains to be dissected. § I used the metacommunity framework to dissect the relative influences of dispersal (in ecological and evolutionary timeframes), selection (driven by abiotic factors) and ecological drift on the assembly process of freshwater benthic communities. § The study was carried out at 26-32 different stream segments within an area of 2 about 40,000km , in the Colombian Orinoco. The area encompasses an elevation gradient from 3400 to 300m a.s.l. and includes a heterogeneous assembly of ecoregions and landscapes. § By using a pattern-matching approach, I provide evidences supporting that dispersal, selection and drift are directly involved in the assembly of freshwater benthic communities. § My findings indicate that one or more events of dispersal limitation (i.e. allopatric isolation) in an evolutionary timeframe shaped distinct pools of taxa in the Orinoco basin. The extent of these pools partially matches the distribution of the ecoregions, suggesting that those events molding the riverscapes and the vegetation structure similarly affect the diversity and distribution of benthic species. § Within each ecoregion, dispersal, selection and drift interact to constrain the structure and dynamics of communities and metacommunities among and within streams. Depending on the taxa belonging to each pool of species, the role of one of these processes may prevail over the others. § These findings have implications for both basic and applied research in the disciplines of metacommunity and freshwater ecology as well as of conservation and biogeography.Linking functional diversity patterns of algae and invertebrates to scale-dependent constrains of rivers from the Orinoco basinTesis con fines de doble titulación bajo el Convenio de cotutela entre la Universidad de Girona y la Universidad Nacional de Colombia.Doctorad

Clave para la determinación de exuvias pupales de los quironómidos (Diptera: Chironomidae) de ríos altoandinos tropicales

The Chironomidae is a cosmopolitan family of Nematoceran flies with more than 20 000 species described. However the diversity of genera and species of the family in the Andean region beyond the 2 000m.a.s.l are scarcely known. We conducted faunal surveys and biomonitoring research in different streams of Colombia, Ecuador and Peru from May 2005 to October 2011. Based on specimens collections, and a taxonomic key was developed to identify pupae and pupal exuviae of 46 genera of midges (Diptera, Chironomidae) collected from streams at high altitude areas on the Andean tropical mountains. We included illustrations and brief taxonomic descriptions for all genera, of which several ones have not yet been formally described; in this latter case we used the nomenclature of Roback & Coffman (1983). For two genera, Cricotopus and Genus 1, keys to the most common morphospecies were provided. Results showed that in this area the chironomid assemblages are dominated by the members of the subfamily Orthocladiinae (22 genera) followed by the Chironominae (13). Six genera of Tanypodinae were identified, while only three and two genera were present from subfamilies Podonominae and Diamesinae. This key may be very useful for both studies about drift in streams, and for biomonitoring purposes

Simulador da mecânica dos fluidos para operações de limpeza e separação de fases em poços verticais e horizontais que utilizam tecnologia coiled tubing.

El artículo presenta el desarrollo de un simulador de los procesos que se llevan a cabo en los pozos de petróleo que manejan la técnica coiled tubing, el cual permite que sus operarios, el personal de la empresa y cualquiera que desee observar estos procesos, pueda evidenciar de manera clara: en qué consisten los métodos de limpieza y separación de fases en dichos pozos y de qué manera se controlan las sustancias que entran y salen del pozo. Además, permite mostrar sus propiedades físicas y facilita que una persona, sin conocimiento previo del tema, pueda entender el objetivo de la inyección de fluidos mediante el coiled tubing en pozos de petróleo. This Project look for the processes simulation that take place in the oil Wells that operate the coiled tubing technique, so its workers, Company personal and anyone that wants to look these processes, can prove that consist in their cleaning methods and phase separation in these Wells, and at the same time, in what way the substances that in and out of well are controlled, show their physical features and allow that a person, without previous knowledge about the topic, may understand easily what is it injection fluid purpose by means of the C. T. in oil Wells. O artigo apresenta o desenvolvimento de um simulador dos processos que são executados nos poços de petróleo que lidam com tecnologia coiled tubing, que permite aos seus operadores, ao pessoal da empresa e a quem quiser observar esses processos, evidenciar claramente: como são os métodos de limpeza e separação de fases nestes poços e a forma em que são monitoradas as substâncias que entram e saem dos poços. Além disso, mostra as propriedades físicas e permite a uma pessoa sem conhecimento prévio do assunto, compreender o objetivo da injeção de fluidos através do coiled tubing em poços de petróleo.

The manifold costs of being a non-native English speaker in science

The use of English as the common language of science represents a major impediment to maximising the contribution of non-native English speakers to science. Yet few studies have quantified the consequences of language barriers on the career development of researchers who are non-native English speakers. By surveying 908 researchers in environmental sciences, this study estimates and compares the amount of effort required to conduct scientific activities in English between researchers from different countries and, thus, different linguistic and economic backgrounds. Our survey demonstrates that non-native English speakers, especially early in their careers, spend more effort than native English speakers in conducting scientific activities, from reading and writing papers and preparing presentations in English, to disseminating research in multiple languages. Language barriers can also cause them not to attend, or give oral presentations at, international conferences conducted in English. We urge scientific communities to recognise and tackle these disadvantages to release the untapped potential of non-native English speakers in science. This study also proposes potential solutions that can be implemented today by individuals, institutions, journals, funders, and conferences.This work was funded by the Australian Research Council Future Fellowship FT180100354 (TA), The University of Queensland strategic funding (TA), and the German Research Foundation (DFG-FZT 118, 202548816) (SC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe

Transgenic Mouse Models of Alzheimer’s Disease: An Integrative Analysis

Alzheimer’s disease (AD) constitutes the most prominent form of dementia among elderly individuals worldwide. Disease modeling using murine transgenic mice was first initiated thanks to the discovery of heritable mutations in amyloid precursor protein (APP) and presenilins (PS) genes. However, due to the repeated failure of translational applications from animal models to human patients, along with the recent advances in genetic susceptibility and our current understanding on disease biology, these models have evolved over time in an attempt to better reproduce the complexity of this devastating disease and improve their applicability. In this review, we provide a comprehensive overview about the major pathological elements of human AD (plaques, tauopathy, synaptic damage, neuronal death, neuroinflammation and glial dysfunction), discussing the knowledge that available mouse models have provided about the mechanisms underlying human disease. Moreover, we highlight the pros and cons of current models, and the revolution offered by the concomitant use of transgenic mice and omics technologies that may lead to a more rapid improvement of the present modeling batterThis research was funded by INSTITUTO DE SALUD CARLOS III (ISCiii) of Spain, cofinanced by FEDER funds from European Union, through grants PI21/00915 (to AG) and PI21/00914 (to JV); by JUNTA DE ANDALUCIA CONSEJERÍA DE ECONOMÍA Y CONOCIMIENTO through grants UMA18-FEDERJA-211 (to AG), UMA20-FEDERJA-104 (to IMG), P18-RT-2233 (to AG) and US-1262734 (to JV) co-financed by Programa Operativo FEDER 2014–2020 and CONSEJERIA DE SALUD grant PI-0276-2018 (to JAGL); by SPANISH MINISTER OF SCIENCE AND INNOVATION grant PID2019-108911RA-100 (to DBV), BEATRIZ GALINDO PROGRAM BAGAL18/00052 (to DBV), Alzheimer Association AARG-22-928219 (to DBV), grant PID2019-107090RA-100 (to IMG) and RAMON Y CAJAL PROGRAM RYC-2017-21879 (to IMG); and by MALAGA UNIVERSITY grant B1-2019_07 (to ESM), grant B1-2020_04 (to JAGL), grant B1-2019_06 (to IMG) and NASARD grant 27565 2018 (to IMG). M.M.-O. held a predoctoral contract from Malaga University, J.J.F.-V. held a postdoctoral contract from Malaga University, and E.S.-M. a postdoctoral contract (DOC_00251) from Junta de Andalucia. Partial funding for open access charge: Universidad de Málaga

Plaque-Associated Oligomeric Amyloid-Beta Drives Early Synaptotoxicity in APP/PS1 Mice Hippocampus: Ultrastructural Pathology Analysis

Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by initial memory impairments that progress to dementia. In this sense, synaptic dysfunction and loss have been established as the pathological features that best correlate with the typical early cognitive decline in this disease. At the histopathological level, post mortem AD brains typically exhibit intraneuronal neurofibrillary tangles (NFTs) along with the accumulation of amyloid-beta (Abeta) peptides in the form of extracellular deposits. Specifically, the oligomeric soluble forms of Abeta are considered the most synaptotoxic species. In addition, neuritic plaques are Abeta deposits surrounded by activated microglia and astroglia cells together with abnormal swellings of neuronal processes named dystrophic neurites. These periplaque aberrant neurites are mostly presynaptic elements and represent the first pathological indicator of synaptic dysfunction. In terms of losing synaptic proteins, the hippocampus is one of the brain regions most affected in AD patients. In this work, we report an early decline in spatial memory, along with hippocampal synaptic changes, in an amyloidogenic APP/PS1 transgenic model. Quantitative electron microscopy revealed a spatial synaptotoxic pattern around neuritic plaques with significant loss of periplaque synaptic terminals, showing rising synapse loss close to the border, especially in larger plaques. Moreover, dystrophic presynapses were filled with autophagic vesicles in detriment of the presynaptic vesicular density, probably interfering with synaptic function at very early synaptopathological disease stages. Electron immunogold labeling showed that the periphery of amyloid plaques, and the associated dystrophic neurites, was enriched in Abeta oligomers supporting an extracellular location of the synaptotoxins. Finally, the incubation of primary neurons with soluble fractions derived from 6-month-old APP/PS1 hippocampus induced significant loss of synaptic proteins, but not neuronal death. Indeed, this preclinical transgenic model could serve to investigate therapies targeted at initial stages of synaptic dysfunction relevant to the prodromal and early AD.This study was supported by the Instituto de Salud Carlos III (ISCiii) of Spain, co-financed by the FEDER funds from European Union, through grants PI18/01557 (to AG) and PI18/01556 (to JV); by the Junta de Andalucia Consejería de Economía y Conocimiento through grants UMA18-FEDERJA-211 (to AG), P18-RT-2233 (to AG), and US-1262734 (to JV) co-financed by Programa Operativo FEDER 2014–2020; by the Spanish Minister of Science and Innovation grant PID2019-108911RA-100 (to DB-V), Beatriz Galindo program BAGAL18/00052 (to DB-V) grant PID2019-107090RA-I00 (to IM-G), and Ramon y Cajal Program RYC-2017-21879 (to IM-G); and by the Malaga University grants B1-2019_07 (to ES-M) and B1-2019_06 (to IM-G). MM-O held a predoctoral contract from Malaga University and ES-M a postdoctoral contract (DOC_00251) from Junta de Andalucia

Animal and Cellular Models of Alzheimer’s Disease: Progress, Promise, and Future Approaches

Alzheimer’s disease (AD) is an incurable neurodegenerative disease affecting over 45 million people worldwide. Transgenic mouse models have made remarkable contributions toward clarifying the pathophysiological mechanisms behind the clinical manifestations of AD. However, the limited ability of these in vivo models to accurately replicate the biology of the human disease have precluded the translation of promising preclinical therapies to the clinic. In this review, we highlight several major pathogenic mechanisms of AD that were discovered using transgenic mouse models. Moreover, we discuss the shortcomings of current animal models and the need to develop reliable models for the sporadic form of the disease, which accounts for the majority of AD cases, as well as human cellular models to improve success in translating results into human treatments.Peer reviewe

Drivers of mangrove vulnerability and resilience to tropical cyclones in the North Atlantic Basin

The North Atlantic Basin (NAB) has seen an increase in the frequency and intensity of tropical cyclones since the 1980s, with record-breaking seasons in 2017 and 2020. However, little is known about how coastal ecosystems, particularly mangroves in the Gulf of Mexico and the Caribbean, respond to these new “climate normals” at regional and subregional scales. Wind speed, rainfall, pre-cyclone forest height, and hydro-geomorphology are known to influence mangrove damage and recovery following cyclones in the NAB. However, previous studies have focused on local-scale responses and individual cyclonic events. Here, we analyze 25 years (1996–2020) of mangrove vulnerability (damage after a cyclone) and 24 years (1996–2019) of short-term resilience (recovery after damage) for the NAB and subregions, using multi-annual, remote sensing-derived databases. We used machine learning to characterize the influence of 22 potential variables on mangrove responses, including human development and long-term climate trends. Our results document variability in the rates and drivers of mangrove vulnerability and resilience, highlighting hotspots of cyclone impacts, mangrove damage, and loss of resilience. Cyclone characteristics mainly drove vulnerability at the regional level. In contrast, resilience was driven by site-specific conditions, including long-term climate trends, pre-cyclone forest structure, soil organic carbon stock, and coastal development (i.e., proximity to human infrastructure). Coastal development is associated with both vulnerability and resilience at the subregional level. Further, we highlight that loss of resilience occurs mostly in areas experiencing long-term drought across the NAB. The impacts of increasing cyclone activity on mangroves and their coastal protection service must be framed in the context of compound climate change effects and continued coastal development. Our work offers descriptive and spatial information to support the restoration and adaptive management of NAB mangroves, which need adequate health, structure, and density to protect coasts and serve as Nature-based Solutions against climate change and extreme weather events.This research was made possible thanks to the generous support from the BNP-PARIBAS Foundation on their 2019 Climate and Biodiversity Initiative call through the CORESCAM (“Coastal Biodiversity Resilience to Increasing Extreme Events in Central America”) project.Peer reviewe

What can we learn from the innovative school for initial and ongoing teacher training? Research proposal

La formación inicial y permanente del profesorado es señalada como una de las claves fundamentales para la mejora del sistema. Sin embargo, para que esto ocurra, la formación del profesorado debe estar vinculada con prácticas educativas de calidad. En este artículo se defiende la investigación cualitativa en innovación educativa a través de los principios de la Teoría Fundamentada como una manera eficaz de construir una teoría sobre la innovación educativa que sea válida y útil para la transformación positiva del sistema educativo

Stakeholders’ Perceptions of Nature-Based Solutions for Hurricane Risk Reduction Policies in the Mexican Caribbean

Nature-based solutions (NbSs) have long recognized the value of coastal and marine ecosystem management and associated ecosystem services as useful tools for climate change mitigation (e.g., blue carbon) and adaptation (e.g., coastal protection against flooding and storm surges). However, NbSs remain poorly acknowledged and mostly absent from coastal planning for disaster risk reduction policies in the Caribbean, as well as from ex-post disaster reconstruction funds. With the increasing frequency and intensity of hurricanes in the region, NbSs are now more needed than ever. Taking Mexico as a representative case study for the wider Caribbean, we here seek to identify and analyze the barriers and opportunities perceived by relevant stakeholders for mainstreaming coastal-marine NbSs into coastal management and disaster risk reduction policies (e.g., mangroves as green infrastructure) to protect coastal societies and national economies against hurricanes. We conduct semi-structured, in-depth interviews with twenty stakeholders covering academic, governmental, tourism, NGO, coastal planning, and financial domains. Among the twenty-three identified barriers, governance, institutional, financial, and human-capacity aspects are the most dominant perceptions behind the current lack of NbS implementation. Future action for the policy integration of NbSs requires widespread political will and better quantification of both the provision of ecosystem services and their economic benefits under conventional markets.The authors would like to express their gratitude to the BNP-PARIBAS Foundation for funding support on their 2019 call on Climate and Biodiversity, under the CORESCAM project. Research has also been supported by Summit Foundation, and FFEM through grants admonished by the Smithsonian Institution and Mesoamerican Reef Fund, as well as the Smithsonian Marine Station contribution number: 1183. The BLUEFLUX project acknowledges core support from the NASA Carbon Monitoring System and NASA’s Terrestrial Ecology Program. We would also like to acknowledge all interviewees involved in this research. RMR-C would like to acknowledge salary contribution from the LIFE-DICET project and gratitude to the European University Institute.Peer reviewe