78 research outputs found

    A global wanderer: Biology, phylogeography and resilience of the introduced ascidian "Styela plicata"

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    [eng] "Styela plicata" is a solitary ascidian introduced all around the world by ship traffic and seems to have many of the required features to become invasive. The main goal of this PhD thesis was to increase our knowledge on the genetic composition of this species, its reproductive features and its capacity to cope with stress during early life-history stages and adulthood. Results indicate that S. plicata is an ancient introduced species that has been travelling around the globe through maritime transport for centuries. It inhabits harbors, marinas and artificial structures, tolerating high concentrations of pollutants. Adults can respond to moderate levels of stressors by adjusting the production of stress-related proteins, but early stages are comparatively much more vulnerable to the harsh conditions that characterize the habitats where this species thrives. A prolonged reproductive period allows S. plicata to exploit temporal windows of favorable conditions and confers a competitive advantage compared to organisms with limited, seasonal reproduction events. Moreover, high genetic variability and the continual presence of larvae also guarantee further reintroduction events and spreading via ship traffic. At present, the distribution of S. plicata appears to be limited by high temperatures, low salinities and other non-investigated factors such as competition and predation. Further studies should determine the dynamics of the few populations co-habiting with native communities to pinpoint all the factors regulating the spread of this species outside enclosed environments.[spa] La ascidia Styela plicata ha sido introducida alrededor del mundo y parece presentar las características necesarias para convertirse en invasora. El objetivo principal de esta tesis Doctoral ha sido incrementar nuestro conocimiento sobre la composición genética de la especie, sus características reproductoras y su habilidad para tolerar condiciones estresantes como adulto pero también a lo largo de las primeras etapas del cliclo de vida. Los resultados han indicado que S. plicata es una introducción antigua, dado que la especie ha estado viajando alrededor del mundo durante los últimos siglos gracias al transporte marítimo. Esta especie habita en puertos, marinas y otras estructuras artificiales, y tolera altas concentraciones de contaminantes. Los adultos pueden responder a niveles moderados de estresores ajustando la producción de proteínas de estrés, pero los primeros estadios del desarrollo son mucho más vulnerables a las condiciones que caracterizan los ambientes en que la especie habita. Un periodo reproductor extenso permite a la especie explotar ventanas temporales de condiciones favorables y confiere a la especie una ventaja competitiva frente a otros organismos con reproducción estacional. Además, la elevada variabilidad genética y la presencia continua de larvas en la columna de agua, garantiza también eventos de reintroducción secundarios y por tanto la dispersión de la especie vía tráfico marítimo. Actualmente, la distribución de S. plicata parece estar limitada por temperaturas elevadas, bajas salinidades y otros factores aún por investigar tales como la competencia y la depredación. La dinámica de las escasas poblaciones en que la especie cohabita con comunidades nativas debería ser estudiada, para detectar los factores que regularían la dispersión de la especie afuera de los ambientes confinados en que actualmente la encontramos

    El teletrabajo y la conciliación: dos políticas públicas diferentes.

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    El estallido de la crisis sanitaria producida por el Covid-19 ha disparado la demanda de teletrabajo a fin de poder mantener la actividad económica y evitar cualquier contagio por el virus. Al trabajar desde casa se evita el desplazamiento de las personas y se reduce considerablemente el contacto entre individuos. El teletrabajo se convierte, así, en la herramienta fundamental para frenar la exposición de las personas al coronavirus. Paralelamente se refuerza la percepción que el trabajo a distancia es una medida política que facilita la conciliación entre la vida familiar y laboral. Sin embargo, a lo largo de estas páginas se pretende demostrar que el teletrabajo es una política pública nacida para introducir una modalidad de trabajo, y, por tanto, no puede resolver el problema de la compatibilidad entre la vida laboral y familiar, a menos que se modifique su concepción actual y se acompañe de otras medidas política

    The sponge microbiome project

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    Marine sponges (phylum Porifera) are a diverse, phylogenetically deep-branching clade known for forming intimate partnerships with complex communities of microorganisms. To date, 16S rRNA gene sequencing studies have largely utilised different extraction and amplification methodologies to target the microbial communities of a limited number of sponge species, severely limiting comparative analyses of sponge microbial diversity and structure. Here, we provide an extensive and standardised dataset that will facilitate sponge microbiome comparisons across large spatial, temporal, and environmental scales. Samples from marine sponges (n = 3569 specimens), seawater (n = 370), marine sediments (n = 65) and other environments (n = 29) were collected from different locations across the globe. This dataset incorporates at least 268 different sponge species, including several yet unidentified taxa. The V4 region of the 16S rRNA gene was amplified and sequenced from extracted DNA using standardised procedures. Raw sequences (total of 1.1 billion sequences) were processed and clustered with (i) a standard protocol using QIIME closed-reference picking resulting in 39 543 operational taxonomic units (OTU) at 97% sequence identity, (ii) a de novo clustering using Mothur resulting in 518 246 OTUs, and (iii) a new high-resolution Deblur protocol resulting in 83 908 unique bacterial sequences. Abundance tables, representative sequences, taxonomic classifications, and metadata are provided. This dataset represents a comprehensive resource of sponge-associated microbial communities based on 16S rRNA gene sequences that can be used to address overarching hypotheses regarding host-associated prokaryotes, including host specificity, convergent evolution, environmental drivers of microbiome structure, and the sponge-associated rare biosphere.T.T. and N.S.W were funded by Australian Research Council Future Fellowships FT140100197 and FT120100480, respectively. T.T. received funds from the Gordon and Betty Moore Foundation. This work was also supported in part by the W.M. Keck Foundation and the John Templeton Foundation. R.K. received funding as a Howard Hughes Medical Institute Early Career Scientist

    International Impact of COVID-19 on the Diagnosis of Heart Disease

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    BACKGROUND The coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified.OBJECTIVES The study sought to assess COVID-19`s impact on global cardiovascular diagnostic procedural volumes and safety practices.METHODS The International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained.RESULTS Surveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoradc echocardiography decreased by 59%, transesophageat echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p < 0.001 for each procedure). hi multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower-middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and teteheatth.CONCLUSIONS COVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world's economically challenged. Further study of cardiovascular outcomes and COVID-19-related changes in care delivery is warranted. (C) 2021 The Authors. Published by Elsevier on behalf of the American College of Cardiology Foundation

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

    Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

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    Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

    Measurement of jet fragmentation in Pb+Pb and pppp collisions at sNN=2.76\sqrt{{s_\mathrm{NN}}} = 2.76 TeV with the ATLAS detector at the LHC

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    Measurements of top-quark pair differential cross-sections in the eμe\mu channel in pppp collisions at s=13\sqrt{s} = 13 TeV using the ATLAS detector

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