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1.
Science ; 364(6437): 272-275, 2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-30890589

RESUMO

The near-Earth asteroid 162173 Ryugu, the target of the Hayabusa2 sample-return mission, is thought to be a primitive carbonaceous object. We report reflectance spectra of Ryugu's surface acquired with the Near-Infrared Spectrometer (NIRS3) on Hayabusa2, to provide direct measurements of the surface composition and geological context for the returned samples. A weak, narrow absorption feature centered at 2.72 micrometers was detected across the entire observed surface, indicating that hydroxyl (OH)-bearing minerals are ubiquitous there. The intensity of the OH feature and low albedo are similar to thermally and/or shock-metamorphosed carbonaceous chondrite meteorites. There are few variations in the OH-band position, which is consistent with Ryugu being a compositionally homogeneous rubble-pile object generated from impact fragments of an undifferentiated aqueously altered parent body.

2.
Euro Surveill ; 18(30): 20546, 2013 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-23929177

RESUMO

Since July 2009, there has been a community outbreak of leishmaniasis in the south-west area of the Madrid autonomous community, Spain, affecting residents from four towns that are geographically close together and share extensive park areas. As of December 2012, 446 cases were reported (6 in 2009, 97 in 2010, 196 in 2011 and 147 in 2012), a mean incidence rate of 22.2 per 100,000 inhabitants during July 2009 and December 2012. The mean age was 44 years (range: 2 months to 95 years); 61.0% were male. A total of 68 (15.2%) had immunosuppressive conditions; 160 (35.9%) had visceral leishmaniasis and 286 (64.1%) cutaneous. A total of 421 (94.4%) cases were confirmed. Leishmania infantum was identified as the agent. Monitoring revealed high densities of the vector Phlebotomus perniciosus. The surveillance system for canine leishmaniasis did not detect any increase in prevalence during the period. Environmental control measures have been taken, such as improvements in sanitation and disinsection in the risk areas and control of the overpopulation of Leporidae, as xenodiagnosis studies have shown that hares play a role as active reservoirs. This is the largest reported community outbreak of leishmaniasis in Europe. The discovery of the new reservoir stands out in the multifactorial aetiology of the outbreak. Epidemiological research and environmental intervention measures are continuing.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Leishmaniose/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Cães , Feminino , Humanos , Incidência , Lactente , Leishmania infantum/isolamento & purificação , Leishmaniose/prevenção & controle , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Distribuição por Sexo , Fatores Socioeconômicos , Espanha/epidemiologia , População Urbana , Adulto Jovem
3.
Mar Pollut Bull ; 60(8): 1170-4, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20451931

RESUMO

Monitoring of sandy beaches after the Prestige oil spill revealed thick subsurface layers (up to 1m thick) of grey-coloured sand. These horizons were sometimes found under more than 3m of clean sand. Examination of the sand by electron microscopy confirmed that the colouring was due to oil-coated sand grains, and revealed a sequence of degradation of buried oil. Further analysis of the sand revealed high concentrations of hydrocarbon in the oil-coated sand and that the main biomarkers were indicative of biodegradation, even though the oil was buried. A set of experiments was designed to analyze the evolution of oil from tar balls to coatings. The results revealed that biodegradation is a secondary process in the changes that take place in the buried oil, and that water flow slows down the appearance of grey sand and that low salinity may hinder the oil degradation process.


Assuntos
Praias , Modelos Químicos , Petróleo/análise , Dióxido de Silício/química , Biodegradação Ambiental , Vazamento de Resíduos Químicos , Monitoramento Ambiental , Cinética , Petróleo/metabolismo
4.
Mar Pollut Bull ; 60(7): 1122-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20493501

RESUMO

To contribute to establishing a historical baseline for future evaluations of the environmental quality of the Ría de Vigo (NW Spain), we report metal contents determined in eight gravity cores obtained at representative locations in 1990 - before the installation of any wastewater treatment plants - and in fractions thereof that were obtained by the BCR sequential extraction method. The results suggest that early diagenesis had been influenced by both hydrodynamic conditions and organic matter input (the latter especially in areas devoted to mariculture), and that anthropogenic inputs had also affected the concentrations and between-fraction distribution of Cu, Pb, Zn and other metals in surficial sediments.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Metais/análise , Rios/química , Poluentes Químicos da Água/análise , Cobre , Geografia , Chumbo , Compostos Orgânicos/análise , Medição de Risco , Espanha , Fatores de Tempo , Zinco
5.
Science ; 312(5778): 1334-8, 2006 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-16741108

RESUMO

The near-infrared spectrometer on board the Japanese Hayabusa spacecraft found a variation of more than 10% in albedo and absorption band depth in the surface reflectance of asteroid 25143 Itokawa. Spectral shape over the 1-micrometer absorption band indicates that the surface of this body has an olivine-rich mineral assemblage potentially similar to that of LL5 or LL6 chondrites. Diversity in the physical condition of Itokawa's surface appears to be larger than for other S-type asteroids previously explored by spacecraft, such as 433 Eros.

6.
Mar Pollut Bull ; 52(10): 1156-68, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16650444

RESUMO

In November 2002, the sinking of the Prestige oil tanker off the Galician coast (N.W. Spain) caused the largest ecological catastrophe in the history of Spain, affecting the coast called the 'Costa da Morte' (Galicia, N.W. Spain). This work is focused on the study of the oil contamination of the intertidal area of two beaches located on this stretch of coast. The study of twenty cores extracted from both beaches has identified fuel embedded in the sedimentary column up to a depth of 2.38 m (this being the maximum depth of extraction). This, along with the presence of oil below the groundwater indicates the existence of a new factor which determines the burial of oil: the morphodynamic behaviour of the beach. Furthermore, this morphodynamic variation conditions the physical appearance of the buried oil. Four different types have been identified: tar-balls (cm), particles (mm), oil coatings on sediment grains and on emulsion, with distribution patterns conditioned by the degree of wave exposure. The analysis of the information obtained have permitted the development of a conceptual model of the burial and oil evolution in the sedimentary column in relation to wave exposure, and thus to the morphodynamic variability of the beach.


Assuntos
Petróleo/análise , Movimentos da Água , Poluentes Químicos da Água/análise , Acidentes de Trabalho , Praias , Sedimentos Geológicos/química , Hidrocarbonetos Acíclicos/análise , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/análise , Navios , Dióxido de Silício/análise , Espanha , Fatores de Tempo
8.
Science ; 267(5201): 1193-4, 1995 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-17789199
9.
Science ; 246(4931): 790-2, 1989 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17748705

RESUMO

Absorption features having depths up to 5% are identified in high-quality, high-resolution reflectance spectra of 16 dark asteroids in the main belt and in the Cybele and Hilda groups. Analogs among the CM2 carbonaceous chondrite meteorites exist for some of these asteroids, suggesting that these absorptions are due to iron oxides in phyllosilicates formed on the asteroidal surfaces by aqueous alteration processes. Spectra of ten additional asteroids, located beyond the outer edge of the main belt, show no discernible absorption features, suggesting that aqueous alteration did not always operate at these heliocentric distances.

10.
Rev Clin Esp ; 185(1): 14-8, 1989 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-2672156

RESUMO

One hundred and sixty patients with symptoms suggestive of pharyngitis were prospectively studied. The responsible agent in 24% of the cases was streptococcus B haemolyticus group A (EGA) with a clear predominance of female (64%) over male (36%) patients. The greatest number of infections by S. Pyogenes was observed in the age group between 5 and 9 years. No positive cases were found in children less than 3 years old. Utilizing the quick latex agglutination test and comparing the results to those obtained with conventional cultures, a diagnostic fiability of 91% was reached, with 94% specificity, 82% sensibility, 82% PPV, and 94% NPV. These results together with the simplicity and convenience of the technique confirm the usefulness of this diagnostic method. No clinical symptom can be significantly related to streptococcus B haemolyticus pharyngitis. The diagnosis based on the clinical picture has turned out inefficient.


Assuntos
Testes de Fixação do Látex , Faringite/diagnóstico , Infecções Estreptocócicas/diagnóstico , Doença Aguda , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Faringite/etiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Streptococcus pyogenes , Fatores de Tempo
11.
Am J Physiol ; 256(6 Pt 1): G989-96, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2735417

RESUMO

An isolated, vascularly perfused duodenojejunum model was developed in the rat to investigate the mechanisms involved in the release of cholecystokinin (CCK) by vascular bombesin (BBS) and luminal nutrients (LN). Immunoreactive peptides released into the portal vein effluent were measured with three antisera that were relatively CCK specific, gastrin specific, and cross-reactive to both CCK and gastrin, respectively. Bombesin (10(-7) M) provoked a biphasic release of CCK, consisting of a transient rise (approximately 700% above basal) followed by a sustained response (approximately 250% above basal). Gastrin accounted for less than 25% of the total immunoreactivity as measured with the nonspecific antiserum. The two phases of the CCK response were related to the dose of BBS in the range 10(-10)-10(-6) M, with a half-maximal effect at 10(-8) M BBS. Tetrodotoxin (TTX, 10(-6) M) reduced the second phase only (by 80%), whereas hexamethonium (10(-4) M) and atropine (10(-5) M) left the two phases unaltered. LN induced a prompt and well-sustained release of CCK (approximately 250% above basal) that was not affected by arterial TTX or atropine. These results demonstrate that BBS stimulated the release of CCK through both a direct pathway and an indirect, noncholinergic mechanism, while the effect of LN did not appear to involve intramural nerves.


Assuntos
Bombesina/farmacologia , Colecistocinina/metabolismo , Duodeno/metabolismo , Jejuno/metabolismo , Animais , Atropina/farmacologia , Bombesina/administração & dosagem , Meios de Cultura , Duodeno/efeitos dos fármacos , Gastrinas/metabolismo , Técnicas In Vitro , Infusões Intra-Arteriais , Jejuno/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Tetrodotoxina/farmacologia
12.
Appl Opt ; 26(4): 664-8, 1987 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-20454196

RESUMO

A coronagraph designed to minimize scattered light in astronomical observations caused by the structure of the primary mirror, secondary mirror, and secondary support structure of a Cassegrainian telescope is described. Direct (1:1) and reducing (2.7:1) imaging of astronomical fields are possible. High-quality images are produced. The coronagraph can be used. with either a 2-D charge-coupled device or photographic film camera. The addition of transmission dispersing optics converts the coronagraph into a low-resolution spectrograph. The instrument is modular and portable for transport to different observatories.

14.
J Relig Health ; 5(1): 77-8, 1966 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24424671
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