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1.
Nature ; 572(7769): 315-317, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31413374

Assuntos
Júpiter , Planetas
2.
Nature ; 561(7721): 36-37, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30185959
3.
Astrobiology ; 18(7): 843-855, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30035638

RESUMO

The icy moons of the outer Solar System present the possibility of subsurface water, habitable conditions, and potential abodes for life. Access to evidence that reveals the presence of life on the icy moons can be facilitated by plumes that eject material from the subsurface out into space. One instrument capable of performing life-search investigations at the icy moons is the MAss SPectrometer for Planetary EXploration/Europa (MASPEX), which constitutes a high-resolution, high-sensitivity multibounce time-of-flight mass spectrometer capable of measuring trace amounts (ppb) of organic compounds. MASPEX has been selected for the NASA Europa Clipper mission and will sample any plumes and the surface-sputtered atmosphere to assess any evidence for habitability and life. MASPEX is capable of similar investigations targeted at other icy moons. Data may be forthcoming from direct sampling but also impact dissociation because of the high speed of some analytes. Impact dissociation is analogous to the dissociation provided by modern analytical pyrolysis methods. Radiolytic dissociation on the europan surface before or during the sputtering process can also induce fragmentation similar to pyrolysis. In this study, we have compiled pyrolysis mass spectrometry data from a variety of biological and nonbiological materials to demonstrate the ability of MASPEX to recognize habitability and detect life in any plumes and atmospheres of icy moons. Key Words: Europa-Icy moons-Life detection-Mass spectrometry-Organic matter. Astrobiology 18, 843-855.


Assuntos
Exobiologia/métodos , Meio Ambiente Extraterreno/química , Vida , Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Exobiologia/instrumentação , Gelo , Júpiter , Espectrometria de Massas/instrumentação , Pirólise
5.
Matern Child Nutr ; 14(2): e12535, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29034551

RESUMO

The aim of this study was to describe early breastfeeding practices (initiation within 1 hr of birth, no prelacteal feeding, and a combination of both-"optimal" early breastfeeding) according to childbirth location in low- and middle-income countries. Using data from the most recent Demographic and Health Survey (2000-2013) for 57 countries, we extracted information on the most recent birth for women aged 15-49 with a live birth in the preceding 24 months. Childbirth setting was self-reported by location (home or facility) and subtype (home delivery with or without a skilled birth attendant; public or private facility). We produced overall world and four region-level summary statistics by applying national population adjusted survey weights. Overall, 39% of children were breastfed within 1 hr of birth (region range 31-60%), 49% received no prelacteal feeding (41-65%), and 28% benefited from optimal early breastfeeding (21-46%). In South/Southeast Asia and Sub-Saharan Africa, early breastfeeding outcomes were more favourable for facility births compared to home births; trends were less consistent in Latin America and Middle East/Europe. Among home deliveries, there was a higher prevalence of positive breastfeeding practices for births with a skilled birth attendant across all regions other than Latin America. For facility births, breastfeeding practices were more favourable among those taking place in the public sector. This study is the most comprehensive assessment to date of early breastfeeding practices by childbirth location. Our results suggest that skilled delivery care-particularly care delivered in public sector facilities-appears positively correlated with favourable breastfeeding practices.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Inquéritos Epidemiológicos/estatística & dados numéricos , Adolescente , Adulto , África , Ásia , Região do Caribe , Estudos Transversais , Países em Desenvolvimento , Feminino , Humanos , Júpiter , América Latina , Pessoa de Meia-Idade , Adulto Jovem
6.
Astrobiology ; 17(12): 1265-1273, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29016193

RESUMO

Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs-relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts-could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as "electron disposal units" for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes. Key Words: Biofilms-Europa-Extraterrestrial life-Hydrothermal systems. Astrobiology 17, 1265-1273.


Assuntos
Exobiologia , Meio Ambiente Extraterreno/química , Júpiter , Origem da Vida , Radiação , Dióxido de Carbono/síntese química , Hidrogênio/química , Gelo , Redes e Vias Metabólicas , Metano/química , Oceanos e Mares , Termodinâmica
7.
Astrobiology ; 17(10): 958-961, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29019413

RESUMO

Evidence of life beyond Earth may be closer than we think, given that the forthcoming missions to the jovian system will be equipped with instruments capable of probing Europa's icy surface for possible biosignatures, including chemical biomarkers, despite the strong radiation environment. Geochemical biomarkers may also exist beyond Europa on icy moons of the gas giants. Sulfur is proposed as a reliable geochemical biomarker for approved and forthcoming missions to the outer solar system. Key Words: JUICE mission-Clipper mission-Geochemical biomarkers-Europa-Moons of the ice giants-Geochemistry-Mass spectrometry. Astrobiology 17, 958-961.


Assuntos
Exobiologia/instrumentação , Meio Ambiente Extraterreno , Júpiter , Voo Espacial/instrumentação , Água/química , Biomarcadores/análise , Exobiologia/métodos , Oceanos e Mares , Termodinâmica
8.
Astrobiology ; 17(9): 840-851, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28665680

RESUMO

To the astrobiologist, Enceladus offers easy access to a potential subsurface biosphere via the intermediacy of a plume of water emerging directly into space. A direct question follows: If we were to collect a sample of this plume, what in that sample, through its presence or its absence, would suggest the presence and/or absence of life in this exotic locale? This question is, of course, relevant for life detection in any aqueous lagoon that we might be able to sample. This manuscript reviews physical chemical constraints that must be met by a genetic polymer for it to support Darwinism, a process believed to be required for a chemical system to generate properties that we value in biology. We propose that the most important of these is a repeating backbone charge; a Darwinian genetic biopolymer must be a "polyelectrolyte." Relevant to mission design, such biopolymers are especially easy to recover and concentrate from aqueous mixtures for detection, simply by washing the aqueous mixtures across a polycharged support. Several device architectures are described to ensure that, once captured, the biopolymer meets two other requirements for Darwinism, homochirality and a small building block "alphabet." This approach is compared and contrasted with alternative biomolecule detection approaches that seek homochirality and constrained alphabets in non-encoded biopolymers. This discussion is set within a model for the history of the terran biosphere, identifying points in that natural history where these alternative approaches would have failed to detect terran life. Key Words: Enceladus-Life detection-Europa-Icy moon-Biosignatures-Polyelectrolyte theory of the gene. Astrobiology 17, 840-851.


Assuntos
Evolução Biológica , Exobiologia , Júpiter , Lua , Água
9.
Proc Natl Acad Sci U S A ; 114(18): 4566-4568, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28461387
11.
Rio de Janeiro; IPEA; 2017. 80 p. graf.(Texto para Discussão / IPEA).
Monografia em Português | LILACS, ECOS | ID: biblio-991852

RESUMO

Este estudo económico sobre regulação, eficiência e acesso à saúde e a medicamentos pretende realizar uma revisão dos modelos de margens dos grossistas e das farmácias (comunitárias) com a dispensa de medicamentos e descrever as metodologias de cálculo das margens de comercialização para alguns países europeus, construindo uma análise de benchmarking da regulamentação existente. Foi realizada extensa pesquisa bibliográfica e revisão de literatura ao longo do projeto, e a análise detalhada incidiu sobre os seguintes países: Portugal, Alemanha, Bélgica, Eslováquia, Eslovénia, Espanha, França, Grécia, Itália e Suíça. Existe uma multiplicidade de metodologias de cálculo, sendo que a maioria dos países aplica margens máximas regulamentadas apenas para medicamentos comparticipados. A literatura existente sugere que os incentivos às farmácias são cruciais para a promoção da dispensa de genéricos, por meio de atribuição de uma remuneração mais elevada para esses medicamentos, que compense a perda de margem. O papel da dispensa tradicional está a ser substituído pela valorização e o reconhecimento do papel clínico do farmacêutico, devendo ser recompensado por modelos de remuneração de fee-for-performance (pagamento por desempenho) conforme descrito na literatura.


Assuntos
Acesso aos Serviços de Saúde , Comercialização de Produtos , Farmácia , Preparações Farmacêuticas , Regulamentação Governamental , Saúde , Júpiter
12.
Mem. Inst. Oswaldo Cruz ; 111(11): 717-719, Nov. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-829245

RESUMO

Major emergency efforts are being mounted for each vector-borne disease epidemiological crisis anew, while knowledge about the biology of arthropods vectors is dwindling slowly but continuously, as is the number of field entomologists. The discrepancy between the rates of production of knowledge and its use and need for solving crises is widening, in particular due to the highly differing time spans of the two concurrent processes. A worldwide web based search using multiple key words and search engines of onsite and online courses in English, Spanish, Portuguese, French, Italian and German concerned with the biology of vectors identified over 140 courses. They are geographically and thematically scattered, the vast majority of them are on-site, with very few courses using the latest massive open online course (MOOC) powerfulness. Over two third of them is given in English and Western Africa is particularity poorly represented. The taxonomic groups covered are highly unbalanced towards mosquitoes. A worldwide unique portal to guide students of all grades and levels of expertise, in particular those in remote locations, is badly needed. This is the objective a new activity supported by the Special Programme for Research and Training in Tropical Diseases (TDR).


Assuntos
Humanos , Animais , Vetores de Doenças , Entomologia/educação , Controle de Insetos , Insetos Vetores , Ensino/estatística & dados numéricos , África , Ásia , Bovinos , América Central , Transmissão de Doença Infecciosa , Educação a Distância/estatística & dados numéricos , Entomologia/estatística & dados numéricos , Júpiter , Idioma , América do Norte , América do Sul
13.
Astrobiology ; 16(10): 755-774, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27552160

RESUMO

Meaningful motion is an unambiguous biosignature, but because life in the Solar System is most likely to be microbial, the question is whether such motion may be detected effectively on the micrometer scale. Recent results on microbial motility in various Earth environments have provided insight into the physics and biology that determine whether and how microorganisms as small as bacteria and archaea swim, under which conditions, and at which speeds. These discoveries have not yet been reviewed in an astrobiological context. This paper discusses these findings in the context of Earth analog environments and environments expected to be encountered in the outer Solar System, particularly the jovian and saturnian moons. We also review the imaging technologies capable of recording motility of submicrometer-sized organisms and discuss how an instrument would interface with several types of sample-collection strategies. Key Words: In situ measurement-Biosignatures-Microbiology-Europa-Ice. Astrobiology 16, 755-774.


Assuntos
Archaea/citologia , Bactérias/citologia , Exobiologia/métodos , Meio Ambiente Extraterreno , Voo Espacial , Corrente Citoplasmática , Planeta Terra , Camada de Gelo/microbiologia , Júpiter , Microscopia , Oceanos e Mares , Saturno , Microbiologia da Água
15.
Ophthalmic Res ; 56(1): 10-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27054695

RESUMO

PURPOSE: To investigate the correlation between retinal vessel calibre and measurements of neurodegeneration in patients with type 2 diabetes (T2D) and no or early diabetic retinopathy (DR). METHODS: Baseline data on 440 patients with T2D from the EUROCONDOR clinical trial were used. DR was graded according to the Early Treatment of Diabetic Retinopathy Study (ETDRS) scale, and patients with ETDRS levels 10-35 were included. Retinal vessel diameters were measured by semi-automatic software. Calibres were summarized into central retinal artery and vein equivalents (CRAE and CRVE). RESULTS: Median age and diabetes duration were 64.0 and 10.3 years, respectively. ETDRS levels were 10 (42.3%), 20 (27.5%) and 35 (30.2%). The median CRAE and CRVE were 146.7 and 215.3 µm, respectively. CRAE did not differ according to ETRDS level (p = 0.12), but wider CRVE were found in patients with higher ETDRS levels (p = 0.04). In a multivariable linear regression model, CRAE was associated with macular ganglion cell layer thickness (coefficient 0.27 per micrometre, p < 0.01), and CRVE was correlated with macular retinal thickness (coefficient -0.07 per micrometre, p = 0.04) and retinal nerve fibre layer thickness at the optic disc (coefficient 0.32 per micrometre, p < 0.01). CONCLUSION: Retinal vessel calibre was independently associated with structural changes of the neuroretina in patients with no or early DR.


Assuntos
Tartarato de Brimonidina/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/complicações , Degeneração Retiniana/diagnóstico , Vasos Retinianos/patologia , Somatostatina/administração & dosagem , Agonistas de Receptores Adrenérgicos alfa 2/uso terapêutico , Idoso , Diabetes Mellitus Tipo 2/diagnóstico , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/tratamento farmacológico , Quimioterapia Combinada , Eletrorretinografia , Feminino , Seguimentos , Hormônios/uso terapêutico , Humanos , Júpiter , Masculino , Pessoa de Meia-Idade , Fármacos Neuroprotetores/administração & dosagem , Soluções Oftálmicas , Estudos Prospectivos , Degeneração Retiniana/etiologia , Degeneração Retiniana/prevenção & controle , Células Ganglionares da Retina/patologia , Fatores de Tempo , Tomografia de Coerência Óptica/métodos , Resultado do Tratamento
18.
Astrobiology ; 16(1): 23-38, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26701303

RESUMO

It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to shield or intercept Earth-bound comets originating in the outer Solar System is poor, and that the importance of jovian planets on the formation of life is not that they act as shields, but rather that they deliver life-enabling volatiles to the terrestrial planets.


Assuntos
Júpiter , Simulação por Computador , Evolução Planetária , Saturno
19.
Nature ; 529(7584): 59-62, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26675732

RESUMO

Thousands of transiting exoplanets have been discovered, but spectral analysis of their atmospheres has so far been dominated by a small number of exoplanets and data spanning relatively narrow wavelength ranges (such as 1.1-1.7 micrometres). Recent studies show that some hot-Jupiter exoplanets have much weaker water absorption features in their near-infrared spectra than predicted. The low amplitude of water signatures could be explained by very low water abundances, which may be a sign that water was depleted in the protoplanetary disk at the planet's formation location, but it is unclear whether this level of depletion can actually occur. Alternatively, these weak signals could be the result of obscuration by clouds or hazes, as found in some optical spectra. Here we report results from a comparative study of ten hot Jupiters covering the wavelength range 0.3-5 micrometres, which allows us to resolve both the optical scattering and infrared molecular absorption spectroscopically. Our results reveal a diverse group of hot Jupiters that exhibit a continuum from clear to cloudy atmospheres. We find that the difference between the planetary radius measured at optical and infrared wavelengths is an effective metric for distinguishing different atmosphere types. The difference correlates with the spectral strength of water, so that strong water absorption lines are seen in clear-atmosphere planets and the weakest features are associated with clouds and hazes. This result strongly suggests that primordial water depletion during formation is unlikely and that clouds and hazes are the cause of weaker spectral signatures.


Assuntos
Atmosfera/química , Meio Ambiente Extraterreno/química , Planetas , Água/análise , Júpiter , Pressão , Espectrofotometria Infravermelho , Telescópios , Temperatura
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