657 research outputs found
Phylogenetic And Molecular Variability Studies Reveal A New Genetic Clade Of Citrus Leprosis Virus C
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Citrus leprosis virus C (CiLV-C) causes a severe disease affecting citrus orchards in the Western hemisphere. This study reveals the molecular variability of the virus by analyzing four genomic regions (p29, p15, MP and RNA2-intergenic region) distributed over its two RNAs. Nucleotide diversity (pi) values were relatively low but statistically different over the analyzed genes and subpopulations, indicating their distinct evolutionary history. Values of pi(p29) and pi(MP) were higher than those of pi(p15) and pi(RNA2-IR), whereas pi(MP) was increased due to novel discovered isolates phylogenetically clustered in a divergent clade that we called SJP. Isolate BR_SP_SJP_01 RNA1 and RNA2 sequences, clade SJP, showed an identity of 85.6% and 88.4%, respectively, with those corresponding to CiLV-C, the type member of the genus Cilevirus, and its RNA2 5'-proximal region was revealed as a minor donor in a putative inter-clade recombination event. In addition to citrus, BR_SP_SJP_01 naturally infects the weed Commelina benghalensis and is efficiently transmitted by Brevipalpus yothersi mites. Our data demonstrated that negative selection was the major force operating in the evaluated viral coding regions and defined amino acids putatively relevant for the biological function of cilevirus proteins. This work provides molecular tools and sets up a framework for further epidemiological studies.86Conselho Nacional de Desenvolvimento Cientifico e Tecnologico [375843/2012-4, 481771/2013-1, 401564/2012-6]Fundacao de Apoio a Pesquisa no Estado de Sao Paulo [2012/18771-0, 2012/20667-7, 2014/08458-9]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
O QUE É FILOSOFIA ECOLÓGICA?
Este breve texto esboça algumas ideias básicas da Filosofia Ecológica, enfatizando a importância e o valor de tais idéias para o estudo da mente e da consciência. Estas considerações levam à formação de uma abordagem ecológica, e o que, aqui, denomino Filosofia Ecológica. Em particular, a Filosofia Ecológica oferece uma saída às confusões e contradições que são comuns ao pensamento acadêmico dominante no que se refere à mente e à consciência
Enhanced weathering and erosion of a cohesive shore platform following the experimental removal of mussels
The organisms inhabiting intertidal platforms can affect their weathering and erosion rates. Research on biotic influences on platform integrity has traditionally emphasized the role of bioeroders (i.e., organisms that scrap or bore into platforms via mechanical and chemical means). Yet, recent studies illustrate that covers of sessile organisms on the surfaces of intertidal platforms can have bioprotective effects by reducing the efficacy of physical weathering and erosion agents. Eroding cliffs fronted by cohesive shore platforms are a pervasive feature along the continental Argentinean coastline (37–52°S). In this study, we investigated how mussel (Brachidontes rodriguezii) cover mediates weathering and erosion of a cohesive, consolidated silt platform at Playa Copacabana (5 km north of Miramar, Buenos Aires Province; 38° 14′ S, 57° 46′ W). By means of mussel removal experiments, we found that mussel cover attenuates variations in platform surface temperatures, enhances moisture retention during low tide, reduces rates of salt crystallization within the pores of the platform material, and attenuates hydrodynamic forcing on the platform surface. Mussel removal also led to a 10% decrease in surface hardness and a 2-mm reduction in platform height after 5 months. Collectively, our findings indicate that mussel beds limit substrate breakdown via heating-cooling, wetting-drying, and salt crystallization and provide some of the first experimental field evidence for the direct impacts of biotic cover on platform erosion. As intertidal platforms protect the cliffs behind from the hydraulic impact of waves, which may be enhanced with future sea-level rise, we posit that the protection of platforms by mussels indirectly moderates coastline retreat, especially on soft cohesive shores.Fil: Gonzalez, Juliana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Coombes, Martin A.. University of Oxford; Reino UnidoFil: Palomo, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Isla, Federico Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Soria, Sabrina Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Gutierrez, Jorge Luis Ceferino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Departamento de Biología; Argentin
Traqueostomía precoz vs tardía en pacientes con síndrome de dificultad respiratoria aguda (SDRA) por SARS-COV-2.
Objetivo principal: Determinar si la traqueostomía precoz (TQp) vs tardía (TQt) disminuye los días de Ventilación Mecánica (VM) en pacientes con SDRA (Síndrome de Dificultad Respiratoria Agudo) secundario a SARS-COV-2 Objetivos secundarios: Determinar si la TQp disminuyen los días de estancia en UCI o en el hospital.
Diseño: Estudio retrospectivo observacional.
Resultados: 165 pacientes fueron ingresados por SDRA secundario a SARS-COV-2, 57 requirieron traqueostomía (34,5%). En 42% de los pacientes se realizó TQp; primeros 14 días de VM y el 58% TQt (a partir del día 15 de VM). Los días de VM fueron menores en el grupo de TQp, 23,5 días (20,3-33) vs TQt, 30 días (25 - 41) (p 0,049). Los días de estancia en UCI y en el hospital fueron menores en el grupo de TQp sin significancia estadística (31,9 vs 34,9, p =0,371 y 44,9 vs 46,2, p=0,755).
La mortalidad global fue del 24,6%; el 30,3% de los pacientes pertenecía el grupo de TQt y el 16,7% al grupo de TQp (p 0,23) Conclusiones: En nuestra serie, los pacientes con TQp requirieron menos días de VM; sin embargo, no encontramos diferencias estadísticamente significativas en los días de estancia en UCI ni en la mortalidad.
Palabras clave: Traqueostomía, Sindrome de Dificultad Respiratoria Aguda (SDRA), SARS-COV-2, ventilación mecánica.
DOI: http://dx.doi.org/10.17268/rmt.2020.v16i01.0
Deep drainage and nitrogen leaching reduction in crop rotations with cover crops
Los cambios de vegetación pueden alterar los flujos de agua y nitrógeno (N) de los ecosistemas. La intensificación de las rotaciones con cultivos de cobertura (CC) otoño-invernales reduce el N del suelo y el riesgo de lixiviación durante los excesos hídricos. El objetivo de este trabajo fue contrastar el drenaje profundo y la lixiviación de N en una rotación soja-maíz con y sin CC, utilizando lisímetros. Se cultivó avena antes de soja y avena+vicia antes de maíz. Las precipitaciones fueron 732 y 562 mm durante los períodos intercultivo 2014 y 2015, y 817 y 705 mm durante los cultivos de soja y maíz, respectivamente. La inclusión de CC redujo el drenaje durante los períodos intercultivo (de 41 a 25% y de 22 a 9% de la precipitación durante el primer y segundo período intercultivo, respectivamente) y durante el cultivo de soja (de 18 a 14% de la precipitación). Durante el cultivo de maíz, el drenaje fue similar en las dos rotaciones; representó el 14% de la precipitación. La concentración media de N-NO3 3 del drenaje fue de 6 y 15 mg/L para la rotación con y sin CC, respectivamente. La inclusión de CC redujo la lixiviación de 35 a 14 y de 17 a 3 kg N/ha durante los períodos intercultivo 2014 y 2015, respectivamente, y de 36 a 3 y de 15 a 6 kg N/ha durante los cultivos de soja y maíz, respectivamente. Estas reducciones, sumadas al aporte adicional de N por fijación biológica de vicia, produjeron balances de N positivos o cercanos a neutro, mientras que la rotación sin CC presentó balances negativos. Además de mejorar la circulación interna de N, las reducciones en el drenaje con CC se pueden traducir en menor recarga del acuífero y contribuir a la regulación de inundaciones durante períodos lluviosos.Ecosystem water and nitrogen (N) fluxes can be altered by vegetation changes. The intensification of crop rotations with fall-winter cover crops (CC) reduces soil N and leaching risk during period of water excess. In this study we used filled-in lysimeters to evaluate the effect of including CC (oats and an oats+vetch mixture) in a soybean-maize rotation on deep drainage and N leaching during a rainy period. Rainfall was 732 and 562 mm during 2014 and 2015 intercropping periods, and 817 and 705 mm during soybean and maize cropping periods, respectively. The introduction of CC reduced drainage during both intercropping periods (from 41 to 25% and from 22 to 9% of rainfall during the first and second intercropping periods, respectively) and during soybean cropping period (from 18 to 14% of rainfall). Drainage represented 14% of the rainfall of maize in both rotations. Mean drainage N-NO3¯ concentration was 6 and 15 mg/L for the rotation with and without CC, respectively, and the introduction of CC reduced leaching from 35 to 14 and from 17 to 3 kg N/ha during 2014 and 2015 intercropping periods, respectively, and from 36 to 3 and from 15 to 6 kg N/ha during soybean and maize cropping periods, respectively. These reductions, together with the additional N input from biological fixation of vetch, produced positive or close to neutral N balances while the rotation without CC produced negative balances. The inclusion of CC in the rotation not only improved internal N circulation. The reduction of drainage can translate into less groundwater recharge and the concomitant contribution to flooding regulation during rainy periods.Fil: Portela, Silvina Isabel. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Restovich, Silvina Beatriz. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Pergamino; ArgentinaFil: Gonzalez, Hugo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional del Noroeste de la Provincia de Buenos Aires. Escuela de Ciencias Agrarias, Naturales y Ambientales; ArgentinaFil: Torti, Maria Juliana. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Pergamino; Argentin
Conocimiento científico y medios de comunicación: desafíos del periodismo científico en Colombia
La noticia debe informar al lector y permitirle construir una opinión sobre el tema leído, sin embargo, los medios de comunicación colombianos no reflejan adecuadamente el papel preponderante que algunas secciones deben tener, debido a la preferencia de los medios de comunicación por noticias blandas y sin mucho contenido. El periodismo científico colombiano atraviesa dos problemas: la falta de especialización de los periodistas y el poco apoyo de los investigadores, sin embargo, en los últimos años se ha incrementado la capacitación de los comunicadores en esta área, cuyo trabajo consiste en convertir el resultado de la investigación a un lenguaje más sencillo para que así sea entendido con mayor facilidad por las audiencias. El objetivo de este artículo de reflexión es describir algunas deficiencias y desafíos que presenta el periodismo científico en Colombia
A Contribuição dos Museus para a Institucionalização e Difusão da Paleontologia.
Since the calls “cabinets of curiosities", the essence of natural history was consolidating itself with the birth of the museums and the development of the Museums of Natural History. This consolidation was reached through following activities: expeditions, field trips, collection classification works, catalogues of diffusion of scientific knowledge, educativ activities and expositions. The present paper intends to discuss the importance of the museal institutions for the studies of Paleontology; since the museums of Natural History had exerted a pioneering paper in the institutionalization of certain areas of knowledge, as Palaeontology, Anthropology and Experimental Physiology, in Brazil. The Paleontological studies in museums had collaborated in the specialization and modernization of the appearance of "new museum idea". As this new concept the museum is a space of diffusion of scientific knowledge, represented as an object that reflects the identity of the society without an obligator linking with physical constructions. However, the Brazilian museums have been sufficientlyobsolete, with problems that involve acquisition and maintenance of collections to production of temporary or permanent exhibitions. When the Brazilian institutions of natural history are analyzed they are not organized on the new museum conception and the digital age as the North American and European ones. Despite the difficulties found by the Museums since its birth as Institution in the 18th century, the contemporary development of Museology and Palaeontology as Science had contributed for the consolidation and institutionalization of both, helping the diffusion of scientific knowledge
CONSERVAÇÃO DE ENERGIA: PROCESSO PARA COMPREENDER SUA TRANSFERÊNCIA E TRANSFORMAÇÃO
Energy is a greatness widely used in physics. Identifying the presence and form of energy in a given phenomenon is neither simple nor understanding its transference and transformation. Considering the possible conversion between them, this work prioritizes different forms of sustainable energy. In view of the above, this research aims to present the importance of energy conservation and, consequently, of natural resources, thus collaborating with the sustainability of the planet. For this, bibliographic research of descriptive and qualitative character was carried out.La energía es una grandeza ampliamente utilizada en física. Identificar la presencia y la forma de energía en un fenómeno dado no es simple ni entender su transferencia y transformación. Teniendo en cuenta la posible conversión entre ellos, este trabajo prioriza diferentes formas de energía sostenible. En vista de lo anterior, esta investigación tiene como objetivo presentar la importancia de la conservación de la energía y, en consecuencia, de los recursos naturales, colaborando así con la sostenibilidad del planeta. Para ello, se realizó una investigación bibliográfica de carácter descriptivo y cualitativo.A energia é uma grandeza muito utilizada na física. Identificar a presença e a forma de energia em um determinado fenômeno não é simples, nem compreender sua transferência e transformação. Considerando a possível conversão entre elas, este trabalho prioriza diferentes formas de energias sustentáveis. Diante do exposto, esta pesquisa visa apresentar a importância da conservação de energia e, consequentemente, dos recursos naturais, colaborando assim, com a sustentabilidade do planeta. Para tanto, foram realizadas pesquisas bibliográficas de caráter descritivo e cunho qualitativo.A energia é uma grandeza muito utilizada na física. Identificar a presença e a forma de energia em um determinado fenômeno não é simples, nem compreender sua transferência e transformação. Considerando a possível conversão entre elas, este trabalho prioriza diferentes formas de energias sustentáveis. Diante do exposto, esta pesquisa visa apresentar a importância da conservação de energia e, consequentemente, dos recursos naturais, colaborando assim, com a sustentabilidade do planeta. Para tanto, foram realizadas pesquisas bibliográficas de caráter descritivo e cunho qualitativo
Label-Free Plasmonic Biosensor for Rapid, Quantitative, and Highly Sensitive COVID-19 Serology: Implementation and Clinical Validation
COVID-19; Biosensor plasmónico; SerologíaCOVID-19; Biosensor plasmònic; SerologiaCOVID-19; Plasmonic biosensor; SerologySerological tests are essential for the control and management of COVID-19 pandemic (diagnostics and surveillance, and epidemiological and immunity studies). We introduce a direct serological biosensor assay employing proprietary technology based on plasmonics, which offers rapid (<15 min) identification and quantification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in clinical samples, without signal amplification. The portable plasmonic device employs a custom-designed multiantigen (RBD peptide and N protein) sensor biochip and reaches detection limits in the low ng mL–1 range employing polyclonal antibodies. It has also been implemented employing the WHO-approved anti-SARS-CoV-2 immunoglobulin standard. A clinical validation with COVID-19 positive and negative samples (n = 120) demonstrates its excellent diagnostic sensitivity (99%) and specificity (100%). This positions our biosensor as an accurate and easy-to-use diagnostics tool for rapid and reliable COVID-19 serology to be employed both at laboratory and decentralized settings for the disease management and for the evaluation of immunological status during vaccination or treatment.ICN2 and UVE acknowledge financial support from H2020 Research and Innovation Programme of the European Commission (H202-SC1-PHE-Coronavirus-2020, CONVAT Project, No. 101003544). The ICN2 is funded by the CERCA program/Generalitat de Catalunya and supported by the Severo Ochoa Centres of Excellence program funded by the Spanish Research Agency (AEI, grant no. SEV-2017-0706). ICN2 group is very grateful to EPI Industries (Barcelona, Spain) for its kind donation supporting our research in COVID-19. O.C.-L. acknowledges the economic support from the Spanish Ministry of Science and Innovation and the Spanish Research Agency and the European Social Fund (ESF) (ref. BES-2017-080527) linked to the TEC 2016-78515-R project Predict. A part of the work was supported by the European Virus Archive GLOBAL (EVA-GLOBAL) project that has received funding from the EU Horizon 2020 (grant agreement No. 871029). A.T. and L.F.-B. acknowledge financial support from GENCAT-DGRIS COVID. We are indebted to all the patients who accepted to participate contributing to science advancement. We are indebted to the HCB-IDIBAPS Biobank for the human samples and data procurement and to the Fundació Glòria Soler for its support to the COVIDBANK collection. We thank the IDIBAPS Biobank for its valuable contribution to sample processing and storage. The authors acknowledge the EU Horizon 2020 Program under grant agreement no. 644956 (RAIS project) for funding the Hospital Vall d’Hebron Biobank. The VHIR-HUVH is supported by Plan Nacional de I + D + i 2013-2016 and ISCIII-Ministerio de Ciencia e Innovación, and Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0003)─cofinanced by European Development Regional Fund “A way to achieve Europe,” Operative program Intelligent Growth 2014. Part of the samples and data from patients included in this study were provided by the Vall d’Hebron University Hospital Biobank (PT17/0015/0047), integrated in the Spanish National Biobanks Network, and they were processed following standard operating procedures with the appropriate approval of the Ethical and Scientific Committee. The authors kindly appreciate the generous donation of samples and clinical data of the donors of the Sepsis Bank of HUVH Biobank and COVID-19 patients attended at HUVH
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