1000 resultados para Coronavirus do peru


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The mineral coquimbite has been analysed using a range of techniques including SEM with EDX, thermal analytical techniques and Raman and infrared spectroscopy. The mineral originated from the Javier Ortega mine, Lucanas Province, Peru. The chemical formula was determined as ðFe3þ 1:37; Al0:63ÞP2:00ðSO4Þ3 9H2O. Thermal analysis showed a total mass loss of 73.4% on heating to 1000 C. A mass loss of 30.43% at 641.4 C is attributed to the loss of SO3. Observed Raman and infrared bands were assigned to the stretching and bending vibrations of sulphate tetrahedra, aluminium oxide/hydroxide octahedra, water molecules and hydroxyl ions. The Raman spectrum shows well resolved bands at 2994, 3176, 3327, 3422 and 3580 cm 1 attributed to water stretching vibrations. Vibrational spectroscopy combined with thermal analysis provides insight into the structure of coquimbite.

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Following the SARS outbreak, extensive surveillance was undertaken globally to detect and identify coronavirus diversity in bats. This study sought to identify the diversity and prevalence of coronaviruses in bats in the Australasian region. We identified four different genotypes of coronavirus, three of which (an alphacoronavirus and two betacoronaviruses) are potentially new species, having less than 90% nucleotide sequence identity with the most closely related described viruses. We did not detect any SARS-like betacoronaviruses, despite targeting rhinolophid bats, the putative natural host taxa. Our findings support the virus-host co-evolution hypothesis, with the detection of Miniopterus bat coronavirus HKU8 (previously reported in Miniopterus species in China, Hong Kong and Bulgaria) in Australian Miniopterus species. Similarly, we detected a novel betacoronavirus genotype from Pteropus alecto which is most closely related to Bat coronavirus HKU9 identified in other pteropodid bats in China, Kenya and the Philippines. We also detected possible cross-species transmission of bat coronaviruses, and the apparent enteric tropism of these viruses. Thus, our findings are consistent with a scenario wherein the current diversity and host specificity of coronaviruses reflects co-evolution with the occasional host shift.

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Parecer apresentado à Commissão de Diplomacia da Câmara dos Deputados

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ENGLISH: A study has been made of the distributions of the 28 species of Chaetognatha in the waters off Peru and southern Ecuador, based primarily on data from oceanographic surveys carried out between 1958 and 1961 by the Inter-American Tropical Tuna Commission, Scripps Institution of Oceanography, and the Institute of Marine Resources Research and Consejo de Investigaciones Hidrobiologicas of Peru. Data from expeditions previous to 1958 also were used to aid in the interpretation of these materials. SPANISH: Se ha realizado un estudio de la distribución de las 28 especies de quetognatos en las aguas frente al Perú y al Ecuador meridional, basado principalmente sobre datos de los reconocimientos oceanográficos efectuados entre 1958 y 1961 por la Comisión Interamericana del Atún Tropical, la Institución Scripps de Oceanografía, y por el Instituto de Investigación de los Recursos Marinos y el Consejo de Investigaciones Hidrobiológicas del Perú. También se emplearon datos de las expediciones anteriores a 1958 para ayudar a la interpretación de este material. (PDF contains 102 pages)

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The fine-scale seismic structure of the central Mexico, southern Peru, and southwest Japan subduction zones is studied using intraslab earthquakes recorded by temporary and permanent regional seismic arrays. The morphology of the transition from flat to normal subduction is explored in central Mexico and southern Peru, while in southwest Japan the spatial coincidence of a thin ultra-slow velocity layer (USL) atop the flat slab with locations of slow slip events (SSEs) is explored. This USL is also observed in central Mexico and southern Peru, where its lateral extent is used as one constraint on the nature of the flat-to-normal transitions.

In western central Mexico, I find an edge to this USL which is coincident with the western boundary of the projected Orozco Fracture Zone (OFZ) region. Forward modeling of the 2D structure of the subducted Cocos plate using a finite-difference algorithm provides constraints on the velocity and geometry of the slab’s seismic structure in this region and confirms the location of the USL edge. I propose that the Cocos slab is currently fragmenting into a North Cocos plate and a South Cocos plate along the projection of the OFZ, by a process analogous to that which occurred when the Rivera plate separated from the proto-Cocos plate 10 Ma.

In eastern central Mexico, observations of a sharp transition in slab dip near the abrupt end of the Trans Mexican Volcanic Belt (TMVB) suggest a possible slab tear located within the subducted South Cocos plate. The eastern lateral extent of the USL is found to be coincident with these features and with the western boundary of a zone of decreased seismicity, indicating a change in structure which I interpret as evidence of a possible tear. Analysis of intraslab seismicity patterns and focal mechanism orientations and faulting types provides further support for a possible tear in the South Cocos slab. This potential tear, together with the tear along the projection of the OFZ to the northwest, indicates a slab rollback mechanism in which separate slab segments move independently, allowing for mantle flow between the segments.

In southern Peru, observations of a gradual increase in slab dip coupled with a lack of any gaps or vertical offsets in the intraslab seismicity suggest a smooth contortion of the slab. Concentrations of focal mechanisms at orientations which are indicative of slab bending are also observed along the change in slab geometry. The lateral extent of the USL atop the horizontal Nazca slab is found to be coincident with the margin of the projected linear continuation of the subducting Nazca Ridge, implying a causal relationship, but not a slab tear. Waveform modeling of the 2D structure in southern Peru provides constraints on the velocity and geometry of the slab’s seismic structure and confirms the absence of any tears in the slab.

In southwest Japan, I estimate the location of a possible USL along the Philippine Sea slab surface and find this region of low velocity to be coincident with locations of SSEs that have occurred in this region. I interpret the source of the possible USL in this region as fluids dehydrated from the subducting plate, forming a high pore-fluid pressure layer, which would be expected to decrease the coupling on the plate interface and promote SSEs.

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O tema da sexualidade na região amazônica do Peru tem sido objeto de diversas elaborações discursivas desde os tempos coloniais, destacando-se certas ideias, como intensidade e desordem. Tais concepções sedimentaram-se em representações de ampla difusão e permanência no país, sendo a charapa ardiente, representação hipersexualizada da mulher amazônica, a mais paradigmática. A existência desses discursos e a escassez de literatura acadêmica sobre o tema da sexualidade nesta região motivaram esta pesquisa, que objetivou explorar o lugar da sexualidade na construção de si, entre mulheres da Amazônia urbana do Peru. Para tal foi efetuada uma revisão de fontes secundárias, dirigida a rastrear a origem desta representação e sua recriação, na história do país. A seguir, a partir de informações obtidas em entrevistas em profundidade com mulheres da região investigada, foram exploradas suas opiniões acerca desta representação e a maneira como lidam com ela, em circunstâncias concretas da vida cotidiana. Os relatos evidenciaram tanto processos de negação como de reprodução e resignificação, em um jogo complexo e flexível, que varia de acordo com o contexto em que as mulheres se encontram. Por outro lado, foram apreendidas as trajetórias afetivo-sexuais das informantes, por intermédio de entrevistas em profundidade, a partir de indagações sobre diversos temas, como iniciação sexual, infidelidade feminina, valoração da atividade sexual e trocas econômico-sexuais, entre outros. Foram identificados eixos estruturantes da vida sexual destas mulheres. Destaca-se um discurso relacional, que enaltece a reciprocidade como marco da vida sexual e, em segundo plano, comparece também uma retórica fisicalista, que considera a atividade sexual como necessidade corporal. Por fim, o estudo evidenciou um importante papel da sexualidade como recurso feminino, no plano econômico, em estreita articulação com dimensões afetivas e considerações familiares. Trata-se de trocas econômico-sexuais que integram a dinâmica cotidiana de reciprocidade nos vínculos afetivo-sexuais.

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Although there have been a number of studies on aquatic conditions and the flora and fauna of Lake Titicaca over many decades, most of this work has been centred on the offshore regions of the main lake. Water quality there has been degrading and abundant growth of Lemna spp. has been developing. Lemna spp., commonly called floating duck-weed or ‘lenteja de agua’ in Puno, occurs perennially in most parts of the inner Puno Bay shore-line. In this article, the authors compare water quality changes over recent decades in shore-line regions of Inner Puno Bay and their possible effects on the distribution, abundance and biomass of Lemna spp..

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Esta tese investiga os sentidos e a experiência da heterogeneidade social nas metrópoles latino-americanas contemporâneas a partir de um estudo de caso de Lima Metropolitana (Peru). Numa perspectiva mais ampla, trata-se da análise, na trajetória histórica de Lima, dos discursos e imaginários construídos sobre a cidade, sobre seus espaços e a diversidade de suas gentes; isto é, as diversas maneiras através das quais a realidade urbana e o pertencimento a ela são concebidos e interpretados em diálogo com os processos de conformação e transformação do espaço urbano, os discursos e imaginários nacionais sobre a cidade, seu cotidiano e sua cultura popular. De modo mais específico, em contraposição às interpretações hegemônicas da heterogeneidade social na contemporaneidade - seja associada ao conflito social e à violência urbana, mobilizada na luta pelo reconhecimento e na reivindicação política de direitos de distintos grupos sociais, ou valorizada como recurso econômico e estratégico pela indústria do turismo e o marketing urbano -, investiga-se a hipótese de construções alternativas da diferença que, ancoradas em sensibilidades práticas e sociabilidades cotidianas, estabelecem vínculos e configuram sentidos de urbanidade, entendida como relação de pertencimento e de reconhecimento do outro, no espaço e tempo compartilhados da urbe.

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A modification of the Schaefer surplus-production model was used to account for environmental induced variations of shrimp (Penaeus vannamei) catch in northern Peru. Based on time series of catch, effort, river discharge and sea surface temperature, fluctuations in catch of shrimps are explained and discussed with respect to multiple level of carrying capacity and hence different maximum sustainable yields.

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Use of wastewater is an issue gaining importance throughout the (developing) world, as water sources become scarcer and competition for them increases. In Peru, research has shown the technical, economic and social feasibility of growing fish in wastewater. Such fish farms could recover 100% of the wastewater treatment costs.