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1.
Zoonoses Public Health ; 65(4): 420-424, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29451368

RESUMO

Melioidosis in humans presents variably as fulminant sepsis, pneumonia, skin infection and solid organ abscesses. It is caused by Burkholderia pseudomallei, which in the United States is classified as a select agent, with "potential to pose a severe threat to both human and animal health, to plant health or to animal and plant products" (Federal Select Agent Program, http://www.selectagents.gov/, accessed 22 September 2016). Burkholderia pseudomallei is found in soil and surface water in the tropics, especially South-East Asia and northern Australia, where melioidosis is endemic. Human cases are rare in the United States and are usually associated with travel to endemic areas. Burkholderia pseudomallei can also infect animals. We describe a multijurisdictional public health response to a case of subclinical urinary B. pseudomallei infection in a dog that had been adopted into upstate New York from a shelter in Thailand. Investigation disclosed three human contacts with single, low-risk exposures to the dog's urine at his residence, and 16 human contacts with possible exposure to his urine or culture isolates at a veterinary hospital. Contacts were offered various combinations of symptom/fever monitoring, baseline and repeat B. pseudomallei serologic testing, and antibiotic post-exposure prophylaxis, depending on the nature of their exposure and their personal medical histories. The dog's owner accepted recommendations from public health authorities and veterinary clinicians for humane euthanasia. A number of animal rescue organizations actively facilitate adoptions into the United States of shelter dogs from South-East Asia. This may result in importation of B. pseudomallei into almost any community, with implications for human and animal health.


Assuntos
Burkholderia pseudomallei/isolamento & purificação , Doenças Transmissíveis Importadas/veterinária , Doenças do Cão/microbiologia , Melioidose/veterinária , Saúde Pública/métodos , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Burkholderia pseudomallei/imunologia , Doenças Transmissíveis Importadas/microbiologia , Doenças do Cão/epidemiologia , Doenças do Cão/urina , Cães/microbiologia , Humanos , Masculino , Melioidose/epidemiologia , Melioidose/microbiologia , Melioidose/transmissão , New York/epidemiologia , Profilaxia Pós-Exposição , Testes Sorológicos , Tailândia/epidemiologia , Viagem
2.
Sci Robot ; 2(7)2017 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-33157897

RESUMO

Limitations on interplanetary communications create operations latencies and slow progress in planetary surface missions, with particular challenges to narrow-field-of-view science instruments requiring precise targeting. The AEGIS (Autonomous Exploration for Gathering Increased Science) autonomous targeting system has been in routine use on NASA's Curiosity Mars rover since May 2016, selecting targets for the ChemCam remote geochemical spectrometer instrument. AEGIS operates in two modes; in autonomous target selection, it identifies geological targets in images from the rover's navigation cameras, choosing for itself targets that match the parameters specified by mission scientists the most, and immediately measures them with ChemCam, without Earth in the loop. In autonomous pointing refinement, the system corrects small pointing errors on the order of a few milliradians in observations targeted by operators on Earth, allowing very small features to be observed reliably on the first attempt. AEGIS consistently recognizes and selects the geological materials requested of it, parsing and interpreting geological scenes in tens to hundreds of seconds with very limited computing resources. Performance in autonomously selecting the most desired target material over the last 2.5 kilometers of driving into previously unexplored terrain exceeds 93% (where ~24% is expected without intelligent targeting), and all observations resulted in a successful geochemical observation. The system has substantially reduced lost time on the mission and markedly increased the pace of data collection with ChemCam. AEGIS autonomy has rapidly been adopted as an exploration tool by the mission scientists and has influenced their strategy for exploring the rover's environment.

3.
Science ; 350(6257): aac7575, 2015 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-26450214

RESUMO

The landforms of northern Gale crater on Mars expose thick sequences of sedimentary rocks. Based on images obtained by the Curiosity rover, we interpret these outcrops as evidence for past fluvial, deltaic, and lacustrine environments. Degradation of the crater wall and rim probably supplied these sediments, which advanced inward from the wall, infilling both the crater and an internal lake basin to a thickness of at least 75 meters. This intracrater lake system probably existed intermittently for thousands to millions of years, implying a relatively wet climate that supplied moisture to the crater rim and transported sediment via streams into the lake basin. The deposits in Gale crater were then exhumed, probably by wind-driven erosion, creating Aeolis Mons (Mount Sharp).


Assuntos
Lagos , Marte , Clima , Exumação , Paleontologia
4.
Science ; 341(6153): 1238670, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24072924

RESUMO

The ChemCam instrument, which provides insight into martian soil chemistry at the submillimeter scale, identified two principal soil types along the Curiosity rover traverse: a fine-grained mafic type and a locally derived, coarse-grained felsic type. The mafic soil component is representative of widespread martian soils and is similar in composition to the martian dust. It possesses a ubiquitous hydrogen signature in ChemCam spectra, corresponding to the hydration of the amorphous phases found in the soil by the CheMin instrument. This hydration likely accounts for an important fraction of the global hydration of the surface seen by previous orbital measurements. ChemCam analyses did not reveal any significant exchange of water vapor between the regolith and the atmosphere. These observations provide constraints on the nature of the amorphous phases and their hydration.

5.
Astrobiology ; 13(8): 740-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23924246

RESUMO

The prospect of a future soft landing on the surface of Europa is enticing, as it would create science opportunities that could not be achieved through flyby or orbital remote sensing, with direct relevance to Europa's potential habitability. Here, we summarize the science of a Europa lander concept, as developed by our NASA-commissioned Science Definition Team. The science concept concentrates on observations that can best be achieved by in situ examination of Europa from its surface. We discuss the suggested science objectives and investigations for a Europa lander mission, along with a model planning payload of instruments that could address these objectives. The highest priority is active sampling of Europa's non-ice material from at least two different depths (0.5-2 cm and 5-10 cm) to understand its detailed composition and chemistry and the specific nature of salts, any organic materials, and other contaminants. A secondary focus is geophysical prospecting of Europa, through seismology and magnetometry, to probe the satellite's ice shell and ocean. Finally, the surface geology can be characterized in situ at a human scale. A Europa lander could take advantage of the complex radiation environment of the satellite, landing where modeling suggests that radiation is about an order of magnitude less intense than in other regions. However, to choose a landing site that is safe and would yield the maximum science return, thorough reconnaissance of Europa would be required prior to selecting a scientifically optimized landing site.


Assuntos
Exobiologia , Geologia , Júpiter , Voo Espacial , Oceanos e Mares
6.
J Clin Microbiol ; 51(9): 3132-6, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23824776

RESUMO

Five laboratory-acquired brucellosis (LAB) cases that occurred in the United States between 2008 and 2011 are presented. The Centers for Disease Control and Prevention (CDC) reviewed the recommendations published in 2008 and the published literature to identify strategies to further prevent LAB. The improved prevention strategies are described.


Assuntos
Brucelose/diagnóstico , Brucelose/prevenção & controle , Controle de Infecções/métodos , Exposição Ocupacional , Adulto , Criança , Feminino , Pessoal de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos
7.
Science ; 340(6136): 1068-72, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23723230

RESUMO

Observations by the Mars Science Laboratory Mast Camera (Mastcam) in Gale crater reveal isolated outcrops of cemented pebbles (2 to 40 millimeters in diameter) and sand grains with textures typical of fluvial sedimentary conglomerates. Rounded pebbles in the conglomerates indicate substantial fluvial abrasion. ChemCam emission spectra at one outcrop show a predominantly feldspathic composition, consistent with minimal aqueous alteration of sediments. Sediment was mobilized in ancient water flows that likely exceeded the threshold conditions (depth 0.03 to 0.9 meter, average velocity 0.20 to 0.75 meter per second) required to transport the pebbles. Climate conditions at the time sediment was transported must have differed substantially from the cold, hyper-arid modern environment to permit aqueous flows across several kilometers.

8.
Epidemiol Infect ; 140(11): 2053-61, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22261286

RESUMO

Multiple salmonellosis outbreaks have been linked to contaminated tomatoes. We investigated a multistate outbreak of Salmonella Typhimurium infections among 190 cases. For hypothesis generation, review of patients' food histories from four restaurant-associated clusters in four states revealed that large tomatoes were the only common food consumed by patients. Two case-control studies were conducted to identify food exposures associated with infections. In a study conducted in nine states illness was significantly associated with eating raw, large, round tomatoes in a restaurant [matched odds ratio (mOR) 3·1, 95% confidence interval (CI) 1·3-7·3]. In a Minnesota study, illness was associated with tomatoes eaten at a restaurant (OR 6·3, mid-P 95% CI 1·05-50·4, P=0·046). State, local and federal regulatory officials traced the source of tomatoes to Ohio tomato fields, a growing area not previously identified in past tomato-associated outbreaks. Because tomatoes are commonly eaten raw, prevention of tomato contamination should include interventions on the farm, during packing, and at restaurants.


Assuntos
Busca de Comunicante , Surtos de Doenças , Microbiologia de Alimentos , Restaurantes , Intoxicação Alimentar por Salmonella/epidemiologia , Salmonella typhimurium/isolamento & purificação , Solanum lycopersicum/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Intoxicação Alimentar por Salmonella/microbiologia , Estados Unidos/epidemiologia , Adulto Jovem
9.
Epidemiol Infect ; 138(4): 491-500, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19751538

RESUMO

Giardiasis is a common waterborne gastrointestinal illness. In 2007, a community giardiasis outbreak occurred in New Hampshire, USA. We conducted a cohort study to identify risk factors for giardiasis, and stool and environmental samples were analysed. Consuming tap water was significantly associated with illness (risk ratio 4.7, 95% confidence interval 1.5-14.4). Drinking-water samples were coliform-contaminated and a suspect Giardia cyst was identified in a home water filter. One well was coliform-contaminated, and testing indicated that it was potentially under the influence of surface water. The well was located 12.5 m from a Giardia-contaminated brook, although the genotype differed from clinical specimens. Local water regulations require well placement at least 15 m from surface water. This outbreak, which caused illness in 31 persons, represents the largest community drinking-water-associated giardiasis outbreak in the USA in 10 years. Adherence to well placement regulations might have prevented this outbreak.


Assuntos
Surtos de Doenças , Giardia/isolamento & purificação , Giardíase/epidemiologia , Água/parasitologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , DNA de Protozoário/química , DNA de Protozoário/genética , Enterobacteriaceae/isolamento & purificação , Feminino , Genótipo , Giardia/classificação , Giardia/genética , Humanos , Masculino , Pessoa de Meia-Idade , New Hampshire/epidemiologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Adulto Jovem
10.
Science ; 325(5936): 58-61, 2009 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-19574383

RESUMO

The Phoenix mission investigated patterned ground and weather in the northern arctic region of Mars for 5 months starting 25 May 2008 (solar longitude between 76.5 degrees and 148 degrees ). A shallow ice table was uncovered by the robotic arm in the center and edge of a nearby polygon at depths of 5 to 18 centimeters. In late summer, snowfall and frost blanketed the surface at night; H(2)O ice and vapor constantly interacted with the soil. The soil was alkaline (pH = 7.7) and contained CaCO(3), aqueous minerals, and salts up to several weight percent in the indurated surface soil. Their formation likely required the presence of water.


Assuntos
Gelo , Marte , Água , Carbonato de Cálcio , Meio Ambiente Extraterreno , Concentração de Íons de Hidrogênio , Robótica , Astronave , Temperatura
11.
Science ; 306(5702): 1733-9, 2004 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-15576609

RESUMO

The Miniature Thermal Emission Spectrometer (Mini-TES) on Opportunity investigated the mineral abundances and compositions of outcrops, rocks, and soils at Meridiani Planum. Coarse crystalline hematite and olivine-rich basaltic sands were observed as predicted from orbital TES spectroscopy. Outcrops of aqueous origin are composed of 15 to 35% by volume magnesium and calcium sulfates [a high-silica component modeled as a combination of glass, feldspar, and sheet silicates (approximately 20 to 30%)], and hematite; only minor jarosite is identified in Mini-TES spectra. Mini-TES spectra show only a hematite signature in the millimeter-sized spherules. Basaltic materials have more plagioclase than pyroxene, contain olivine, and are similar in inferred mineral composition to basalt mapped from orbit. Bounce rock is dominated by clinopyroxene and is close in inferred mineral composition to the basaltic martian meteorites. Bright wind streak material matches global dust. Waterlain rocks covered by unaltered basaltic sands suggest a change from an aqueous environment to one dominated by physical weathering.


Assuntos
Marte , Minerais , Sulfato de Cálcio , Meio Ambiente Extraterreno , Compostos Férricos , Sedimentos Geológicos , Compostos de Ferro , Compostos de Magnésio , Sulfato de Magnésio , Silicatos , Astronave , Sulfatos , Água
12.
Science ; 305(5685): 800-6, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15297658

RESUMO

Panoramic Camera images at Gusev crater reveal a rock-strewn surface interspersed with high- to moderate-albedo fine-grained deposits occurring in part as drifts or in small circular swales or hollows. Optically thick coatings of fine-grained ferric iron-rich dust dominate most bright soil and rock surfaces. Spectra of some darker rock surfaces and rock regions exposed by brushing or grinding show near-infrared spectral signatures consistent with the presence of mafic silicates such as pyroxene or olivine. Atmospheric observations show a steady decline in dust opacity during the mission, and astronomical observations captured solar transits by the martian moons, Phobos and Deimos, as well as a view of Earth from the martian surface.


Assuntos
Marte , Atmosfera , Evolução Planetária , Meio Ambiente Extraterreno , Compostos Férricos , Sedimentos Geológicos , Compostos de Ferro , Minerais , Silicatos , Sistema Solar , Análise Espectral , Água
13.
Science ; 305(5685): 810-3, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15297660

RESUMO

Wind-abraded rocks, ripples, drifts, and other deposits of windblown sediments are seen at the Columbia Memorial Station where the Spirit rover landed. Orientations of these features suggest formative winds from the north-northwest, consistent with predictions from atmospheric models of afternoon winds in Gusev Crater. Cuttings from the rover Rock Abrasion Tool are asymmetrically distributed toward the south-southeast, suggesting active winds from the north-northwest at the time (midday) of the abrasion operations. Characteristics of some rocks, such as a two-toned appearance, suggest that they were possibly buried and exhumed on the order of 5 to 60 centimeters by wind deflation, depending on location.


Assuntos
Marte , Evolução Planetária , Meio Ambiente Extraterreno , Vento
14.
Science ; 305(5685): 821-4, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15297662

RESUMO

The precise location and relative elevation of Spirit during its traverses from the Columbia Memorial station to Bonneville crater were determined with bundle-adjusted retrievals from rover wheel turns, suspension and tilt angles, and overlapping images. Physical properties experiments show a decrease of 0.2% per Mars solar day in solar cell output resulting from deposition of airborne dust, cohesive soil-like deposits in plains and hollows, bright and dark rock coatings, and relatively weak volcanic rocks of basaltic composition. Volcanic, impact, aeolian, and water-related processes produced the encountered landforms and materials.


Assuntos
Marte , Meio Ambiente Extraterreno , Sedimentos Geológicos , Erupções Vulcânicas , Água , Vento
15.
Science ; 305(5685): 837-42, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15297667

RESUMO

The Miniature Thermal Emission Spectrometer (Mini-TES) on Spirit has studied the mineralogy and thermophysical properties at Gusev crater. Undisturbed soil spectra show evidence for minor carbonates and bound water. Rocks are olivinerich basalts with varying degrees of dust and other coatings. Dark-toned soils observed on disturbed surfaces may be derived from rocks and have derived mineralogy (+/-5 to 10%) of 45% pyroxene (20% Ca-rich pyroxene and 25% pigeonite), 40% sodic to intermediate plagioclase, and 15% olivine (forsterite 45% +/-5 to 10). Two spectrally distinct coatings are observed on rocks, a possible indicator of the interaction of water, rock, and airfall dust. Diurnal temperature data indicate particle sizes from 40 to 80 microm in hollows to approximately 0.5 to 3 mm in soils.


Assuntos
Marte , Minerais , Carbonatos , Sedimentos Geológicos , Interferometria , Compostos de Ferro , Compostos de Magnésio , Óxidos , Silicatos , Análise Espectral , Temperatura , Água
16.
Science ; 305(5685): 842-5, 2004 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-15297668

RESUMO

The Spirit landing site in Gusev Crater on Mars contains dark, fine-grained, vesicular rocks interpreted as lavas. Pancam and Mini-Thermal Emission Spectrometer (Mini-TES) spectra suggest that all of these rocks are similar but have variable coatings and dust mantles. Magnified images of brushed and abraded rock surfaces show alteration rinds and veins. Rock interiors contain

Assuntos
Marte , Minerais , Silicatos , Meio Ambiente Extraterreno , Sedimentos Geológicos , Compostos de Ferro , Compostos de Magnésio , Óxidos , Espectroscopia de Mossbauer , Análise Espectral , Água
18.
Lancet ; 346(8989): 1560, 1995 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-7491068
20.
Nurs Manage ; 24(2): 54, 56, 58, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8429976

RESUMO

This assessment center helps unit directors critique their own managerial strengths and weaknesses and formulate effective self-improvement plans and growth strategies. Structured activities also provide a framework for administrators to identify managerial talent and to develop potential nurse managers effectively.


Assuntos
Pessoal Administrativo , Avaliação de Desempenho Profissional , Enfermeiros Administradores , Competência Profissional , Educação Continuada , Humanos
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