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1.
Sci Total Environ ; 751: 142159, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33181999

RESUMO

A consistent and equitable global drought risk assessment for multiple regions, populations, and economic sectors at the gridded scale under future diverse climate change scenarios has been the subject of scarce research. Climate change is projected to increase the future hazard of drought and cause consequential damages to socioeconomic systems. The risk assessment of drought caused by climate change can be a bridge between impacts and adaptation. To assess the socioeconomic risk to droughts in a base period and two future periods (2016 to 2035 and 2046 to 2065), the projections of five general circulation models and population and gross domestic product (GDP), land cover, and water resources data were used to analyze the socioeconomic risk under three scenarios combining representative concentration pathways (RCPs) and shared socioeconomic pathways (SSPs). The socioeconomic risk was calculated as the product of three determinants: hazard, exposure, and vulnerability. The risk of the global population to drought was projected to be highest in 2046 to 2065 under scenario RCP8.5-SSP3, with up to 1.45 × 109 persons affected, a 63% increase compared with the base period. The highest risk to GDP (4.29 × 1013 purchasing power parity $) was possibly in 2046 to 2065 under scenario RCP2.6-SSP1, with the risk increasing 5.64 times compared to the base period. Regions with high socioeconomic risk were primarily concentrated in the East and South Asia, Midwestern Europe, eastern US, and the coastal areas of South America. With climate change, the inequality in future socioeconomic risk to drought among countries is predicted to increase. The ten countries with the highest risks to population and GDP accounted for nearly 70% of the global risk.


Assuntos
Secas , Modelos Teóricos , Ásia , Mudança Climática , Europa (Continente) , Fatores Socioeconômicos , América do Sul
2.
Food Chem ; 334: 127555, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32711268

RESUMO

Conjugated linoleic acid (CLA) content of ruminant milk reported in published research papers (n = 65) from January 1995 to March 2020 around the world were analyzed to estimate the overall mean CLA value. The CLA content of ruminant milk samples was grouped according to geographical regions (Europe, South America, North America, Oceania, Asia, and Africa). The total CLA content of milk samples from cows, sheep, goats, yaks, and llama retrieved from the collected data ranged between 0.06 and 2.96% of total fatty acids. There is a wide variation of pooled estimated mean content of CLA in milk among the study regions and were highest in Oceania with 1.33% (95% confidence interval (CI): 1.16 - 1.49%) of total fatty acids. Though several factors have been reported to influence the CLA content of milk, the effect of the "geographical origin" was only considered in the present manuscript as one of the main factors in this respect.


Assuntos
Ácidos Linoleicos Conjugados/análise , Leite/química , África , Animais , Ásia , Bovinos , Europa (Continente) , Ácidos Graxos/análise , Cabras , América do Norte , Oceania , Ruminantes , Ovinos , América do Sul
3.
Sci Total Environ ; 751: 141728, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32890797

RESUMO

Trees significantly impact land-atmosphere feedbacks through evapotranspiration, photosynthesis and isoprene emissions. These processes influence the local microclimate, air quality and can mitigate temperature extremes and sequester carbon dioxide. Despite such importance, currently only 5 out of 15 atmospheric chemistry climate models even partially account for the presence of cropland trees. We first show that the tree cover over intensely farmed regions in Asia, Australia and South America is significantly underestimated (e.g. only 1-3% tree cover over north-India) in the Model of Emissions of Gases and Aerosol from Nature (MEGAN) and absent in Noah land-surface module of the Weather Research and Forecasting (WRF-Chem) Model. By including the actual tree cover (~10%) over the north-west Indo Gangetic Plain in the Noah land-surface module of the WRF-Chem and the MEGAN module, during the rice growing monsoon season in August, we find that the latent heat flux alone increases by 100%-300% while sensible heat flux reduces by 50%-100%, leading to a reduction in daytime boundary layer height by 200-400 m. This greatly improves agreement between the modelled and measured temperature, boundary layer height and surface ozone, which were earlier overestimated and isoprene and its oxidation products which were earlier underestimated. Mitigating peak daytime temperatures and ozone improves rice production by 10 to 20%. Our findings from north west Indo-Gangetic Plain establish that such plantations mitigate heat stress, and have beneficial effects on crop yields while also sequestering carbon. Expanding agroforestry practices to 50% of the cropland area could result in up to 40% yield gain regionally. Implementing such strategies globally could increase crop production and sequester 0.3-30 GtC per year, and therefore future climate mitigation and food security efforts should consider stakeholder participation for increased cropland agroforestry in view of its beneficial effects.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , Ásia , Atmosfera , Austrália , Produtos Agrícolas , Monitoramento Ambiental , Índia , Ozônio/análise , América do Sul , Temperatura , Árvores
4.
An Acad Bras Cienc ; 92(3): e20181251, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206796

RESUMO

Ilex paraguariensis (yerba mate) is a native species from South America and is a rich source of bioactive compounds. There is a lack of research efforts on the phytochemical investigation of callus culture from this species. In the present study, an effort was made to optimize callus culture conditions and to identify secondary compounds. Calli were induced from 10 genotypes using leaf explants and the best genotype was selected to evaluate the effects of cytokinin types and concentrations on callus induction and biomass accumulation. The best genotype and cytokinin treatment were used to conduct one last experiment with sucrose concentrations in culture media and its effects on calli biomass, antioxidant activity and secondary compounds accumulation. Callus initiation was genotype dependent, and the 6-156-6 line had the best response. Zeatin supplemented medium showed higher callus induction rate (82%) and higher biomass accumulation after 120 days (328.2 mg). Higher biomass and secondary compounds accumulation were observed for calli on 3% sucrose medium. Antioxidant activity was not affected by sucrose concentrations. Yerba mate callus culture allowed the accumulation of chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, theobromine and caffeine.


Assuntos
Ilex paraguariensis , Genótipo , Extratos Vegetais , Folhas de Planta , América do Sul
5.
Dis Aquat Organ ; 142: 33-40, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33210609

RESUMO

Pinniped tuberculosis, commonly caused by Mycobacterium pinnipedii, is a zoonotic disease reported in free-living and captive otariid species of the southern hemisphere. Currently, data concerning pinniped tuberculosis in South America are scarce, reinforcing the need for further studies of the disease in free-ranging pinnipeds. In this study, we investigated the presence of tuberculosis in South American sea lions Otaria flavescens (SASLs) stranded along the Chubut coastline (Argentina). Necropsies were performed in 9 SASLs, and tissue samples were collected for histopathology, bacteriology, and molecular diagnosis. Four SASLs showed enlarged tracheobronchial lymph nodes (TBLNs) with multifocal to coalescing granulomas. In these animals, a direct IS6110-PCR amplification confirmed the presence of a Mycobacterium tuberculosis complex member in TBLNs (n = 4) and lungs (n = 2), but the agent could not be further identified. In one SASL, Mycobacterium murale was isolated from lungs without lesions. This study confirms the presence of tuberculosis in SASLs from Chubut, where tourist activities promote close interaction with the animals, generating a potential risk to human health. Further research is currently focusing on addressing the prevalence of tuberculosis in wild SASLs, to assess the risk for public health and develop management strategies to avoid human infection.


Assuntos
Mycobacterium , Leões-Marinhos , Tuberculose , Animais , Argentina/epidemiologia , Humanos , América do Sul , Tuberculose/epidemiologia , Tuberculose/veterinária
6.
Rev Panam Salud Publica ; 44, nov. 2020https://doi.org/10.26633/RPSP.2020.148.
Artigo em Inglês | PAHO-IRIS | ID: phr-53011

RESUMO

[ABSTRACT]. Objectives. The analysis of transmission dynamics is crucial to determine whether mitigation or suppression measures reduce the spread of coronavirus disease 2019 (COVID-19). This study sought to estimate the basic (R0) and time-varying (Rt) reproduction number of COVID-19 and contrast the public health measures for ten South American countries. Methods. Data was obtained from the European Centre for Disease Prevention and Control. Country-specific R0 values during the first two weeks of the outbreak and Rt values after 90 days were estimated. Results. Countries used a combination of isolation, physical distancing, quarantine, and community-wide containment measures to staunch the spread of COVID-19 at different points in time. R0 ranged from 1.52 (95% confidence interval: 1.13-1.99) in Venezuela to 3.83 (3.04-4.75) in Chile, whereas Rt after 90 days ranged from 0.71 (95% credible interval: 0.39-1.05) in Uruguay to 1.20 (1.19-1.20) in Brazil. Different R0 and Rt values may be related to the testing capacity of each country. Conclusion. R0 in the early phase of the outbreak varied across the South American countries. The public health measures adopted in the initial period of the pandemic appear to have reduced Rt over time in each country, albeit to different levels.


[RESUMEN]. Objetivos. Estimar el número de reproducción básico (R0) y el número de reproducción efectivo (Rt) de la COVID-19 y contrastarlos con las medidas de salud pública implementadas en diez países de América del Sur. Métodos. Los datos se obtuvieron del Centro Europeo para la Prevención y el Control de las Enfermedades. Se estimó el R0 de cada país durante las dos primeras semanas del brote y el Rt después de 90 días. Resultados. Los países utilizaron una combinación de aislamiento, distanciamiento físico, cuarentena y medidas de contención en toda la comunidad para detener la propagación de la COVID-19 en diferentes momentos. El R0 osciló entre 1,52 (IC95%: 1,13-1,99) en Venezuela y 3,83 (IC95%: 3,04-4,75) en Chile, mientras que el Rt después de 90 días varió entre 0,71 (intervalo de credibilidad 95%: 0,39-1,05) en Uruguay y 1,20 (intervalo de credibilidad 95%: 1,19-1,20) en Brasil. Los diferentes valores de R0 y Rt pueden estar relacionados con la capacidad de llevar a cabo pruebas de detección viral de cada país. Conclusión. Los valores del R0 en la fase inicial del brote variaron entre los países sudamericanos. Las medidas de salud pública adoptadas en el período inicial de la pandemia parecen haber reducido el Rt con el tiempo en cada país, aunque en niveles diferentes.


Assuntos
Infecções por Coronavirus , Síndrome Respiratória Aguda Grave , Betacoronavirus , Número Básico de Reprodução , Doenças Transmissíveis , Doenças Transmissíveis Emergentes , Pandemias , Epidemiologia , América do Sul , Síndrome Respiratória Aguda Grave , Número Básico de Reprodução , Doenças Transmissíveis Emergentes , Pandemias , Epidemiologia , América do Sul , Doenças Transmissíveis , Coronavirus , Infecções por Coronavirus , Infecções por Coronavirus
7.
Artigo em Inglês | PAHO-IRIS | ID: phr-52997

RESUMO

[ABSTRACT]. Objective. To identify emerging mental health problems, strategies to address them, and opportunities to reform mental health systems during the COVID-19 pandemic in South America. Methods. An online questionnaire was sent to mental health decision-makers of ministries of health in 10 South American countries in mid-April 2020. The semi-structured questionnaire had 12 questions clustered into three main sections: emerging challenges in mental health, current and potential strategies to face the pandemic, and key elements for mental health reform. We identified keywords and themes for each section through summative content analysis. Results. Increasing mental health burden and needs were reported as direct and indirect consequences of the COVID-19 pandemic. National lockdowns challenge the delivery and access to mental health treatment and care. Strategies to meet mental health needs rely heavily on timely and adequate responses by strengthened mental health governance and systems, availability of services, virtual platforms, and appropriate capacity- building for service providers. Short- and medium-term strategies focused on bolstering community-based mental health networks and telemedicine for high-risk populations. Opportunities for long-term mental health reform entail strengthening legal frameworks, redistribution of financial resources, and collaboration with local and international partners. Conclusions. Mental health and psychosocial support have been identified as a priority area by South American countries in the COVID-19 response. The pandemic has generated specific needs that require appropriate actions, including implementing virtual interventions, orienting capacity-building toward protecting users and health providers, strengthening evidence-driven decision-making, and integrating mental health and psychosocial support in high-level mechanisms guiding the response to COVID-19.


[RESUMEN]. Objetivo. Determinar los problemas de salud mental emergentes, las estrategias para abordarlos y las oportunidades para reformar los sistemas de salud durante la pandemia de COVID-19 en América del Sur. Métodos. A mediados de abril del 2020, se envió un cuestionario en línea a los encargados de tomar decisiones en materia de salud mental en los Ministerios de Salud de diez países de América del Sur. El cuestionario semiestructurado consistía en doce preguntas agrupadas en tres secciones principales: desafíos emergentes en materia de salud mental, estrategias actuales y posibles para enfrentar la pandemia, y elementos clave para la reforma de la salud mental. Establecimos palabras clave y temas para cada sección mediante el análisis del contenido sumativo. Resultados. Se informó un aumento de la carga y las necesidades en materia de salud mental como consecuencia directa e indirecta de la pandemia de COVID-19. Los confinamientos a nivel nacional representan un desafío en la prestación y el acceso al tratamiento y la atención de la salud mental. Las estrategias para satisfacer las necesidades de salud mental dependen en gran medida de las respuestas oportunas y adecuadas, que requieren el fortalecimiento de la gobernanza y de los sistemas en el ámbito de la salud mental, la disponibilidad de servicios y plataformas virtuales, y la formación de capacidad apropiada para los prestadores de servicios. Las estrategias a corto y mediano plazo se centran en reforzar las redes comunitarias de salud mental y la telemedicina para los grupos poblacionales de alto riesgo. Las oportunidades para la reforma de la salud mental a largo plazo entrañan fortalecer los marcos jurídicos, la redistribución de los recursos financieros y la colaboración con los asociados a nivel nacional e internacional. Conclusiones. En los países de América del Sur, se ha determinado que la salud mental y el apoyo psicosocial son un área prioritaria en la respuesta a la COVID-19. La pandemia ha generado necesidades específicas que requieren medidas apropiadas, como las intervenciones virtuales, la orientación de la formación de capacidad hacia la protección de los usuarios y prestadores de servicios de salud, el fortalecimiento de la toma de decisiones basadas en la evidencia, y la integración de la salud mental y el apoyo psicosocial en los mecanismos de alto nivel que guían la respuesta a la COVID-19.


[RESUMO]. Objetivo. Identificar problemas emergentes de saúde mental, as estratégias para enfrentá-los e oportunidades para reformar os sistemas de saúde mental durante a pandemia de COVID-19 na América do Sul. Métodos. Em meados de abril de 2020, enviamos um questionário online aos responsáveis pela tomada de decisões em saúde mental dos ministérios da saúde de 10 países da América do Sul. O questionário semiestruturado continha 12 perguntas agrupadas em três seções principais: desafios emergentes em saúde mental, estratégias atuais e potenciais para enfrentar a pandemia e elementos-chave para a reforma da saúde mental. Identificamos palavras-chave e temas para cada seção através da análise de conteúdo sumativa. Resultados. O aumento das necessidades e da carga sobre os serviços de saúde mental foram descritos como consequências diretas e indiretas da pandemia de COVID-19. As medidas de confinamento implementadas pelos governos nacionais dificultam o acesso e a prestação de cuidados e tratamentos de saúde mental. As estratégias para atender às necessidades de saúde mental dependem de respostas rápidas e adequadas através do fortalecimento da governança e dos sistemas de saúde mental, da disponibilidade de serviços, de plataformas virtuais e da capacitação apropriada dos prestadores de serviços. As estratégias de curto e médio prazo se concentraram no reforço das redes comunitárias de saúde mental e da telemedicina para as populações de alto risco. As oportunidades de reforma da saúde mental a longo prazo implicam o fortalecimento dos quadros jurídicos, a redistribuição de recursos financeiros e a colaboração com parceiros locais e internacionais. Conclusões. A saúde mental e o apoio psicossocial foram identificados como uma área prioritária pelos países da América do Sul na resposta à COVID-19. A pandemia criou necessidades específicas que exigem ações apropriadas, incluindo a implementação de intervenções virtuais, a capacitação orientada à proteção dos usuários e prestadores da atenção à saúde, o fortalecimento da tomada de decisões baseada em evidências e a integração da saúde mental e do apoio psicossocial em mecanismos de alto nível que orientem a resposta à COVID-19.


Assuntos
Saúde Mental , Infecções por Coronavirus , Infecções por Coronavirus , Coronavirus , América do Sul , Saúde Mental , Infecções por Coronavirus , América do Sul , Saúde Mental , Infecções por Coronavirus , América do Sul
8.
Nat Commun ; 11(1): 5184, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33056977

RESUMO

The global monsoon is characterised by transitions between pronounced dry and wet seasons, affecting food security for two-thirds of the world's population. Rising atmospheric CO2 influences the terrestrial hydrological cycle through climate-radiative and vegetation-physiological forcings. How these two forcings affect the seasonal intensity and characteristics of monsoonal precipitation and runoff is poorly understood. Here we use four Earth System Models to show that in a CO2-enriched climate, radiative forcing changes drive annual precipitation increases for most monsoon regions. Further, vegetation feedbacks substantially affect annual precipitation in North and South America and Australia monsoon regions. In the dry season, runoff increases over most monsoon regions, due to stomatal closure-driven evapotranspiration reductions and associated atmospheric circulation change. Our results imply that flood risks may amplify in the wet season. However, the lengthening of the monsoon rainfall season and reduced evapotranspiration will shorten the water resources scarcity period for most monsoon regions.


Assuntos
Dióxido de Carbono/metabolismo , Modelos Teóricos , Chuva , Recursos Hídricos , Vento , Atmosfera/química , Austrália , Ciclo do Carbono , Dióxido de Carbono/análise , Mudança Climática , Planeta Terra , Inundações , América do Norte , Estações do Ano , América do Sul , Temperatura , Ciclo Hidrológico
9.
Zootaxa ; 4801(1): zootaxa.4801.1.3, 2020 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-33056672

RESUMO

More than 100 species have been referred to Rhamdia since its description, but in the last revision of the genus more than two decades ago, only eleven species have been considered as valid. Rhamdia quelen was then redefined to include 47 junior synonyms, resulting in a species with a large distribution in the Neotropics, from Mexico to Argentina. Populations of Rhamdia from west of the Andes have been recently removed from the synonymy of R. quelen, and currently there are 27 species recognized in the genus. Most cis-Andean populations, however, remain referred to the R. quelen species complex. In this paper, we use species delimitation methods and multilocus phylogenetic analyses to delimit the species contained in the R. quelen species complex in cis-Andean river drainages. Eighteen MOTUs in the gene tree were recovered with high support. We further demonstrate that the previous designation of a neotype for R. quelen is invalid, and has to be replaced by the proper designation of a neotype from the type locality of the species. The neotype is designated herein and R. quelen is diagnosed and redescribed.


Assuntos
Peixes-Gato , Animais , Variação Genética , Filogenia , América do Sul
10.
Rev Soc Bras Med Trop ; 53: e20200179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027415

RESUMO

INTRODUCTION: Plasmodium vivax malaria represents a major public health problem. This study presents the quality assessment of clinical practice guidelines for the management of P. vivax malaria. METHODS: A systematic review was conducted in PubMed, SciELO, and Google Scholar. Additionally, five guidelines were assessed with the AGREE (Appraisal of Guidelines Research and Evaluation) II protocol. RESULTS: The general performance on the domains of stakeholder involvement, development rigor, and editorial independence was low. CONCLUSIONS: Most guidelines lack a solid research methodology, which implies ambiguous accuracy. Much needs to be done in the area of therapeutics and quality of policies.


Assuntos
Malária Vivax , Coleta de Dados , Humanos , Saúde Pública , Projetos de Pesquisa , América do Sul
11.
Zootaxa ; 4786(1): zootaxa.4786.1.9, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-33056501

RESUMO

Suphisellus grossoi sp. n. is described from the Reserva Natural del Bosque de Mbaracayú, Canindeyú department, Paraguay. Diagnostic characters are described and illustrated in detail. New records are provided for S. flavolineatus (Régimbart, 1889) and S. grammicus (Sharp, 1882), which are also briefly diagnosed. Suphisellus melzeri Zimmermann, 1925 is proposed as a junior subjective synonym of S. flavolineatus (syn. n.), and lectotypes are designated for both taxa.


Assuntos
Besouros , Animais , América do Sul , Água
12.
Zootaxa ; 4816(2): zootaxa.4816.2.5, 2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-33055705

RESUMO

Acanthemblemaria aceroi new species is described from the upwelling region of the Caribbean coasts of Venezuela and Colombia. It differs from its closest relative, Acanthemblemaria rivasi Stephens, 1970, known from Panama and Costa Rica, in the posterior extent of the infraorbitals, details of head spination, and unique COI sequences. The description of Acanthemblemaria johnsonsi Almany Baldwin, 1996, heretofore known only from Tobago, is expanded based on specimens from islands offshore of eastern Venezuela.


Assuntos
Peixes , Animais , Região do Caribe , América do Sul
13.
Zootaxa ; 4806(1): zootaxa.4806.1.1, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33056001

RESUMO

We propose a revision of the spider genus Corythalia C.L. Koch, 1850 (Salticidae: Euophryini) with a revised genus diagnosis based on examination of all species available to us. In this paper we redescribe all previously described species from South America with revised species diagnoses and describe 20 new species from South America (and the nearby islands). For C. latipes, the type species of the genus Corythalia, a neotype is designated. In total, 52 nominal species of the genus are herein treated, 46 species are recognized as valid. The females of C. waleckii Taczanowski, 1871, C. luctuosa Caporiacco, 1954 and C. latipes (C.L. Koch, 1846) are described for the first time. Corythalia sellata Simon, 1901, erroneously considered as nomen nudum in the present version of the World Spider Catalog, is here recognised as a valid species. Corythalia fulgipedia Crane, 1948 is also considered a valid species and is removed from the synonymy of C. tropica (Mello-Leitão, 1939). One name is considered a nomen dubium (Corythalia variegata Caporiacco, 1954), two are nomina nuda (C. major Simon, 1901; C. dimidiata Simon, 1901). Two species are transferred to other genera: C. argyrochrysos (Mello-Leitão, 1946) to Pachomius Peckham Peckham, 1896 as Pachomius argyrochrysos (Mello-Leitão, 1946), comb. nov. and C. heliophanina (Taczanowski, 1871) to Neonella Gertsch, 1936, as Neonella heliophanina (Taczanowski, 1871), comb. nov. under incertae sedis. One species is synonymised: C. barbipes (Mello-Leitão, 1939) is a junior synonym of C. cincta (Badcock, 1932), syn. nov. The new Corythalia species are: C. conferta sp. nov. (♂♀, Brazil), C. concinna sp. nov. (♀, Brazil), C. drepane sp. nov. (♂♀, Brazil), C. drepanopsis sp. nov. (♀, Brazil), C. antepagmenti sp. nov. (♂♀, Brazil), C. ricti Bayer, sp. nov. (♂, Guyana), C. protensa sp. nov. (♂, Brazil), C. gasnieri sp. nov. (♂, Brazil), C. verhaaghi sp. nov. (♀, Brazil), C. scutellaris Bayer, sp. nov. (♂♀, Ecuador), C. dakryodes Bayer, sp. nov. (♀, Colombia), C. foelixi Bayer, sp. nov. (♂♀, French Guiana), C. longiducta sp. nov. (♀, Brazil), C. latior sp. nov. (♂, Bolivia), C. trochophora Bayer, sp. nov. (♂, Ecuador), C. lineata Bayer, sp. nov. (♂, Guyana), C. hamulifera Bayer, sp. nov. (♂, Ecuador), C. tribulosa sp. nov. (♂, Colombia), C. flagrans sp. nov. (♂, Brazil) and C. fragilis sp. nov. (♂♀, Brazil). Illustrations are provided for all of the new species and for all (primary) type specimens of the species re-described. Hypotheses of possible relationships among the different species of Corythalia are discussed.


Assuntos
Aranhas , Animais , Feminino , América do Sul
14.
J Plant Res ; 133(6): 827-839, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33090298

RESUMO

Sagittaria is a genus of ca. 40 species in the aquatic plant family Alismataceae with a nearly global distribution, and a center of diversity in the New World. Two thirds of the known species are native to the Americas, while only a few species are distributed in Africa, Asia and Europe. A previous biogeographic analysis of the genus suggested an African origin for the genus with subsequent dispersal to North America and then to East Asia. Here we expanded the taxon sampling with a focus on the New World taxa and applied species delimitation and biogeographic analyses to revise the knowledge of the phylogeny and evolution of the genus. We obtained largely similar topologies from the chloroplast DNA and nuclear DNA (ITS) data sets. The 74 accessions sampled for our analyses were delimited into 29 species and several cryptic taxa were revealed in widely distributed species. Biogeographic analysis supported basal diversification in South America and subsequent colonization to North America and Asia.


Assuntos
Evolução Biológica , Filogenia , Sagittaria/classificação , África , Ásia , Teorema de Bayes , DNA de Cloroplastos/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Europa (Continente) , Extremo Oriente , América do Norte , Análise de Sequência de DNA , América do Sul
15.
Front Immunol ; 11: 2008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013857

RESUMO

Coronavirus disease (COVID-19), caused by the virus SARS-CoV-2, is already responsible for more than 4.3 million confirmed cases and 295,000 deaths worldwide as of May 15, 2020. Ongoing efforts to control the pandemic include the development of peptide-based vaccines and diagnostic tests. In these approaches, HLA allelic diversity plays a crucial role. Despite its importance, current knowledge of HLA allele frequencies in South America is very limited. In this study, we have performed a literature review of datasets reporting HLA frequencies of South American populations, available in scientific literature and/or in the Allele Frequency Net Database. This allowed us to enrich the current scenario with more than 12.8 million data points. As a result, we are presenting updated HLA allelic frequencies based on country, including 91 alleles that were previously thought to have frequencies either under 5% or of an unknown value. Using alleles with an updated frequency of at least ≥5% in any South American country, we predicted epitopes in SARS-CoV-2 proteins using NetMHCpan (I and II) and MHC flurry. Then, the best predicted epitopes (class-I and -II) were selected based on their binding to South American alleles (Coverage Score). Class II predicted epitopes were also filtered based on their three-dimensional exposure. We obtained 14 class-I and four class-II candidate epitopes with experimental evidence (reported in the Immune Epitope Database and Analysis Resource), having good coverage scores for South America. Additionally, we are presenting 13 HLA-I and 30 HLA-II novel candidate epitopes without experimental evidence, including 16 class-II candidates in highly exposed conserved areas of the NTD and RBD regions of the Spike protein. These novel candidates have even better coverage scores for South America than those with experimental evidence. Finally, we show that recent similar studies presenting candidate epitopes also predicted some of our candidates but discarded them in the selection process, resulting in candidates with suboptimal coverage for South America. In conclusion, the candidate epitopes presented provide valuable information for the development of epitope-based strategies against SARS-CoV-2, such as peptide vaccines and diagnostic tests. Additionally, the updated HLA allelic frequencies provide a better representation of South America and may impact different immunogenetic studies.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Epitopos de Linfócito T/imunologia , Frequência do Gene , Antígenos HLA/genética , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Proteínas do Envelope Viral/imunologia , Alelos , Sequência de Aminoácidos , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Variação Genética , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , América do Sul/epidemiologia , Vacinas de Subunidades/imunologia , Vacinas Virais/imunologia
16.
Nat Commun ; 11(1): 4978, 2020 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020475

RESUMO

Tropical forests modify the conditions they depend on through feedbacks at different spatial scales. These feedbacks shape the hysteresis (history-dependence) of tropical forests, thus controlling their resilience to deforestation and response to climate change. Here, we determine the emergent hysteresis from local-scale tipping points and regional-scale forest-rainfall feedbacks across the tropics under the recent climate and a severe climate-change scenario. By integrating remote sensing, a global hydrological model, and detailed atmospheric moisture tracking simulations, we find that forest-rainfall feedback expands the geographic range of possible forest distributions, especially in the Amazon. The Amazon forest could partially recover from complete deforestation, but may lose that resilience later this century. The Congo forest currently lacks resilience, but is predicted to gain it under climate change, whereas forests in Australasia are resilient under both current and future climates. Our results show how tropical forests shape their own distributions and create the climatic conditions that enable them.


Assuntos
Florestas , Clima Tropical , África , Ásia Sudeste , Austrália , Mudança Climática , Conservação dos Recursos Naturais , Ecossistema , Retroalimentação , Chuva , América do Sul
17.
An Acad Bras Cienc ; 92(3): e20181242, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111816

RESUMO

Ten-year seasonal climate reforecasts over South America are obtained using the Eta Regional Climate Model at 40 km resolution, driven by the large-scale forcing from the global atmospheric model of the Center for Weather Forecasts and Climate Studies. The objective of this work is to evaluate these regional reforecasts. The dataset is comprised of four-month seasonal forecasts performed on a monthly basis between 2001 and 2010. An ensemble of five members is constructed from five slightly different initial conditions to partially reduce the uncertainty in the seasonal forecasts. The seasonal mean precipitation and 2-meter temperature forecasts are compared with the observations. The comparison shows that, in general, forecasted precipitation is underestimated in the central part of the continent in the austral summer, whereas the forecasted 2 meter temperature is underestimated in most parts of the continent and throughout the year. Skill scores show higher skill in the northern part of the continent and lower skill in the southern part of the continent, but mixed skill signs are seen in the central part of the continent. During the El Niño and La Niña seasons, the forecast skill scores clearly increase. The downscaling of the Eta model seasonal forecasts provides added value over the driver global model forecasts, especially during rainy periods.


Assuntos
Clima , Tempo (Meteorologia) , Chuva , Estações do Ano , América do Sul
18.
An Acad Bras Cienc ; 92(3): e20190967, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111820

RESUMO

The enigmatic genus Stenocrates Burmeister has 52 species that are widely distributed from Mexico to Argentina, but mainly in South America. In the present study, the larva of the third instar and pupa of Stenocrates agricola Dechambre & Hardy, 2004 are described and illustrated based on specimens from Argentina, this being the first description of immatures for the genus. The adult is also redescribed, significantly expanding the number of characters and providing information on the natural history of this species. In addition, 28 species of Cyclocephalini and 20 species of Pentodontini are morphologically compared, emphasizing the most useful larval characters used among these beetles. Stenocrates agricola shows frequent and common characters of Pentodontini species but scarce (and even absent) characters typical of Cyclocephalini species, including some considered diagnostic for this tribe. Accordingly we consider that the tribal position of Stenocrates remains controversial and more study is needed to clarify the tribal status of Stenocrates. We believe that larval morphology provides important information in systematics studies that can clarify tribal relationships within the Dynastinae.


Assuntos
Besouros , Animais , Argentina , Larva , México , Pupa , América do Sul
19.
PLoS Negl Trop Dis ; 14(10): e0008686, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33119616

RESUMO

As the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic continues to expand, healthcare resources globally have been spread thin. Now, the disease is rapidly spreading across South America, with deadly consequences in areas with already weakened public health systems. The Amazon region is particularly susceptible to the widespread devastation from Coronavirus disease 2019 (COVID-19) because of its immunologically fragile native Amerindian inhabitants and epidemiologic vulnerabilities. Herein, we discuss the current situation and potential impact of COVID-19 in the Amazon region and how further spread of the epidemic wave could prove devastating for many Amerindian people living in the Amazon rainforest.


Assuntos
Infecções por Coronavirus/etnologia , Índios Sul-Americanos , Pneumonia Viral/etnologia , Betacoronavirus , Infecções por Coronavirus/mortalidade , Humanos , Pandemias , Pneumonia Viral/mortalidade , Floresta Úmida , América do Sul/epidemiologia
20.
Recurso na Internet em Português | LIS - Localizador de Informação em Saúde | ID: lis-47844

RESUMO

A diretora da Organização Pan-Americana da Saúde (OPAS), Carissa F. Etienne, pediu nesta quinta-feira (27) ao bloco PROSUL de presidentes sul-americanos para trabalharem juntos no acesso às vacinas contra a COVID-19.


Assuntos
Infecções por Coronavirus , Vacinas , América do Sul
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