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1.
Plant Dis ; 101(8): 1489-1499, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30678581

RESUMEN

Conventional detection of viruses and virus-like diseases of plants is accomplished using a combination of molecular, serological, and biological indexing. These are the primary tools used by plant virologists to monitor and ensure trees are free of known viral pathogens. The biological indexing assay, or bioassay, is considered to be the "gold standard" as it is the only method of the three that can detect new, uncharacterized, or poorly characterized viral disease agents. Unfortunately, this method is also the most labor intensive and can take up to three years to complete. Next generation sequencing (NGS) is a technology with rapidly expanding possibilities including potential applications for the detection of plant viruses. In this study, comparisons are made between tree fruit testing by conventional and NGS methods, to demonstrate the efficacy of NGS. A comparison of 178 infected trees, many infected with several viral pathogens, demonstrated that conventional and NGS were equally capable of detecting known viruses and viroids. Comparable results were obtained for 170 of 178 of the specimens. Of the remaining eight specimens, some discrepancies were observed between viruses detected by the two methods, representing less than 5% of the specimens. NGS was further demonstrated to be equal or superior for the detection of new or poorly characterized viruses when compared with a conventional bioassay. These results validated both the effectiveness of conventional virus testing methods and the use of NGS as an additional or alternative method for plant virus detection.


Asunto(s)
Patología de Plantas , Virus de Plantas , Viroides , Frutas/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Virus de Plantas/genética , Viroides/genética
2.
Health Econ ; 26(3): 292-304, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-26676999

RESUMEN

We provide evidence for the causal impact of social status on longevity by exploiting a natural experiment in which subjects undergo a shift in their social status without considerable economic impact. We gather data on 4190 scientists who were either nominated for or successfully elected to the Chinese Academy of Science or of Engineering. Being elected as an academician in China is a boost in social status (vice-ministerial level) with negligible direct economic impact (US$30 monthly before 2009). After correcting for two sources of bias, (1) some potential academicians decease too young to be elected, leading to selection bias in favor of academicians and (2) the endogenous relationship between health and social status, we find that the enhanced social status of becoming an academician leads to approximately 1.2 years longer life. Copyright © 2015 John Wiley & Sons, Ltd.


Asunto(s)
Comités Consultivos/estadística & datos numéricos , Longevidad , Clase Social , Comités Consultivos/tendencias , China , Países en Desarrollo , Estado de Salud , Humanos , Persona de Mediana Edad , Política
3.
Ir Med J ; 104(4): 105-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21675091

RESUMEN

Children in care in Ireland have increased by 27% in the last decade. This population is recognized to be among the most vulnerable. This study aims to describe their placement histories, service use and mental health needs. Data was obtained on 174 children (56.5% of eligible sample) with a mean age of 10.83 (SD = 5.04). 114 (65.5%) were in care for three years or more. 29 (16.7%) did not have a SW and 49 (37.7%) had no GP 50 (28.7%) were attending CAMHS. Long term care, frequent placement changes and residential setting were significantly related with poorer outcomes and increased MH contact. Given the increase in numbers in care and the overall decrease in resource allocation to health and social care, individual care planning and prioritizing of resources are essential.


Asunto(s)
Cuidados en el Hogar de Adopción , Necesidades y Demandas de Servicios de Salud , Servicios de Salud Mental , Instituciones Residenciales , Adolescente , Niño , Hijo de Padres Discapacitados , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Irlanda , Masculino , Psicología Infantil , Adulto Joven
5.
Science ; 313(5787): 635-40, 2006 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-16840662

RESUMEN

Spitzer Space Telescope imaging spectrometer observations of comet 9P/Tempel 1 during the Deep Impact encounter returned detailed, highly structured, 5- to 35-micrometer spectra of the ejecta. Emission signatures due to amorphous and crystalline silicates, amorphous carbon, carbonates, phyllosilicates, polycyclic aromatic hydrocarbons, water gas and ice, and sulfides were found. Good agreement is seen between the ejecta spectra and the material emitted from comet C/1995 O1 (Hale-Bopp) and the circumstellar material around the young stellar object HD100546. The atomic abundance of the observed material is consistent with solar and C1 chondritic abundances, and the dust-to-gas ratio was determined to be greater than or equal to 1.3. The presence of the observed mix of materials requires efficient methods of annealing amorphous silicates and mixing of high- and low-temperature phases over large distances in the early protosolar nebula.

6.
Science ; 311(5766): 1453-5, 2006 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-16456037

RESUMEN

We report the direct detection of solid water ice deposits exposed on the surface of comet 9P/Tempel 1, as observed by the Deep Impact mission. Three anomalously colored areas are shown to include water ice on the basis of their near-infrared spectra, which include diagnostic water ice absorptions at wavelengths of 1.5 and 2.0 micrometers. These absorptions are well modeled as a mixture of nearby non-ice regions and 3 to 6% water ice particles 10 to 50 micrometers in diameter. These particle sizes are larger than those ejected during the impact experiment, which suggests that the surface deposits are loose aggregates. The total area of exposed water ice is substantially less than that required to support the observed ambient outgassing from the comet, which likely has additional source regions below the surface.


Asunto(s)
Hielo/análisis , Meteoroides , Espectrofotometría Infrarroja
7.
Science ; 310(5746): 258-64, 2005 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-16150978

RESUMEN

Deep Impact collided with comet Tempel 1, excavating a crater controlled by gravity. The comet's outer layer is composed of 1- to 100-micrometer fine particles with negligible strength (<65 pascals). Local gravitational field and average nucleus density (600 kilograms per cubic meter) are estimated from ejecta fallback. Initial ejecta were hot (>1000 kelvins). A large increase in organic material occurred during and after the event, with smaller changes in carbon dioxide relative to water. On approach, the spacecraft observed frequent natural outbursts, a mean radius of 3.0 +/- 0.1 kilometers, smooth and rough terrain, scarps, and impact craters. A thermal map indicates a surface in equilibrium with sunlight.


Asunto(s)
Meteoroides , Júpiter , Compuestos Orgánicos/análisis , Análisis Espectral
8.
Science ; 310(5746): 265-9, 2005 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-16150977

RESUMEN

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.


Asunto(s)
Meteoroides , Polvo Cósmico , Júpiter , Compuestos Orgánicos , Fotometría
9.
Occup Med (Lond) ; 55(5): 369-70, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15923201

RESUMEN

BACKGROUND: The food industry regulates various aspects of food handler activities, according to legislation and customer expectations. The purpose of this paper is to provide a code of practice which delineates a set of working standards for food handler hygiene, handwashing, use of protective equipment, wearing of jewellery and body piercing. METHODS: The code was developed by a working group of occupational physicians with expertise in both food manufacturing and retail, using a risk assessment approach. Views were also obtained from other occupational physicians working within the food industry and the relevant regulatory bodies. The final version of the code (available in full as Supplementary data in Occupational Medicine Online) therefore represents a broad consensus of opinion. CONCLUSION: The code of practice represents a set of minimum standards for food handler suitability and activities, based on a practical assessment of risk, for application in food businesses. It aims to provide useful working advice to food businesses of all sizes.


Asunto(s)
Manipulación de Alimentos/normas , Industria de Alimentos/normas , Higiene/normas , Gestión de Riesgos/normas , Perforación del Cuerpo , Contaminación de Alimentos/prevención & control , Humanos , Medición de Riesgo
10.
Science ; 288(5469): 1193-8, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10817986

RESUMEN

During late 1999/early 2000, the solid state imaging experiment on the Galileo spacecraft returned more than 100 high-resolution (5 to 500 meters per pixel) images of volcanically active Io. We observed an active lava lake, an active curtain of lava, active lava flows, calderas, mountains, plateaus, and plains. Several of the sulfur dioxide-rich plumes are erupting from distal flows, rather than from the source of silicate lava (caldera or fissure, often with red pyroclastic deposits). Most of the active flows in equatorial regions are being emplaced slowly beneath insulated crust, but rapidly emplaced channelized flows are also found at all latitudes. There is no evidence for high-viscosity lava, but some bright flows may consist of sulfur rather than mafic silicates. The mountains, plateaus, and calderas are strongly influenced by tectonics and gravitational collapse. Sapping channels and scarps suggest that many portions of the upper approximately 1 kilometer are rich in volatiles.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Vuelo Espacial , Erupciones Volcánicas , Fenómenos Geológicos , Geología , Aumento de la Imagen , Espectrofotometría Infrarroja
11.
Science ; 285(5429): 870-4, 1999 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-10436151

RESUMEN

The Galileo spacecraft has detected diffuse optical emissions from Io in high-resolution images acquired while the satellite was eclipsed by Jupiter. Three distinct components make up Io's visible emissions. Bright blue glows of more than 300 kilorayleighs emanate from volcanic plumes, probably due to electron impact on molecular sulfur dioxide. Weaker red emissions, possibly due to atomic oxygen, are seen along the limbs, brighter on the pole closest to the plasma torus. A faint green glow appears concentrated on the night side of Io, possibly produced by atomic sodium. Io's disk-averaged emission diminishes with time after entering eclipse, whereas the localized blue glows brighten instead.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Oxígeno , Dióxido de Azufre , Atmósfera , Sodio
12.
Science ; 281(5373): 87-90, 1998 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-9651251

RESUMEN

Infrared wavelength observations of Io by the Galileo spacecraft show that at least 12 different vents are erupting lavas that are probably hotter than the highest temperature basaltic eruptions on Earth today. In at least one case, the eruption near Pillan Patera, two independent instruments on Galileo show that the lava temperature must have exceeded 1700 kelvin and may have reached 2000 kelvin. The most likely explanation is that these lavas are ultramafic (magnesium-rich) silicates, and this idea is supported by the tentative identification of magnesium-rich orthopyroxene in lava flows associated with these high-temperature hot spots.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Silicatos , Calor , Minerales , Espectrofotometría Infrarroja , Erupciones Volcánicas
13.
Nature ; 391(6665): 363-5, 1998 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-9450749

RESUMEN

Ground-based spectroscopy of Jupiter's moon Europa, combined with gravity data, suggests that the satellite has an icy crust roughly 150 km thick and a rocky interior. In addition, images obtained by the Voyager spacecraft revealed that Europa's surface is crossed by numerous intersecting ridges and dark bands (called lineae) and is sparsely cratered, indicating that the terrain is probably significantly younger than that of Ganymede and Callisto. It has been suggested that Europa's thin outer ice shell might be separated from the moon's silicate interior by a liquid water layer, delayed or prevented from freezing by tidal heating; in this model, the lineae could be explained by repetitive tidal deformation of the outer ice shell. However, observational confirmation of a subsurface ocean was largely frustrated by the low resolution (>2 km per pixel) of the Voyager images. Here we present high-resolution (54 m per pixel) Galileo spacecraft images of Europa, in which we find evidence for mobile 'icebergs'. The detailed morphology of the terrain strongly supports the presence of liquid water at shallow depths below the surface, either today or at some time in the past. Moreover, lower-resolution observations of much larger regions suggest that the phenomena reported here are widespread.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Hielo , Análisis Espectral
14.
Nature ; 391(6665): 365-8, 1998 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-9450750

RESUMEN

The ice-rich surface of the jovian satellite Europa is sparsely cratered, suggesting that this moon might be geologically active today. Moreover, models of the satellite's interior indicate that tidal interactions with Jupiter might produce enough heat to maintain a subsurface liquid water layer. But the mechanisms of interior heat loss and resurfacing are currently unclear, as is the question of whether Europa has (or had at one time) a liquid water ocean. Here we report on the morphology and geological interpretation of distinct surface features-pits, domes and spots-discovered in high-resolution images of Europa obtained by the Galileo spacecraft. The features are interpreted as the surface manifestation of diapirs, relatively warm localized ice masses that have risen buoyantly through the subsurface. We find that the formation of the features can be explained by thermally induced solid-state convection within an ice shell, possibly overlying a liquid water layer. Our results are consistent with the possibility that Europa has a liquid water ocean beneath a surface layer of ice, but further tests and observations are needed to demonstrate this conclusively.


Asunto(s)
Medio Ambiente Extraterrestre , Júpiter , Fenómenos Geológicos , Geología , Hielo
15.
Nature ; 391(6665): 368-70, 1998 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-9450751

RESUMEN

Non-synchronous rotation of Europa was predicted on theoretical grounds, by considering the orbitally averaged torque exerted by Jupiter on the satellite's tidal bulges. If Europa's orbit were circular, or the satellite were comprised of a frictionless fluid without tidal dissipation, this torque would average to zero. However, Europa has a small forced eccentricity e approximately 0.01 , generated by its dynamical interaction with Io and Ganymede, which should cause the equilibrium spin rate of the satellite to be slightly faster than synchronous. Recent gravity data suggest that there may be a permanent asymmetry in Europa's interior mass distribution which is large enough to offset the tidal torque; hence, if non-synchronous rotation is observed, the surface is probably decoupled from the interior by a subsurface layer of liquid or ductile ice. Non-synchronous rotation was invoked to explain Europa's global system of lineaments and an equatorial region of rifting seen in Voyager images. Here we report an analysis of the orientation and distribution of these surface features, based on initial observations made by the Galileo spacecraft. We find evidence that Europa spins faster than the synchronous rate (or did so in the past), consistent with the possibility of a global subsurface ocean.


Asunto(s)
Júpiter
16.
Nature ; 391(6665): 371-3, 1998 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-9450752

RESUMEN

Images obtained by the Voyager spacecraft revealed dark, wedge-shaped bands on Europa that were interpreted as evidence that surface plates, 50-100 km across, moved and rotated relative to each other. This implied that they may be mechanically decoupled from the interior by a layer of warm ice or liquid water. Here we report similar features seen in higher resolution images (420 metres per pixel) obtained by the Galileo spacecraft that reveal new details of wedge-band formation. In particular, the interior of one dark band shows bilateral symmetry of parallel lineaments and pit complexes which indicates that plate separation occurred in discrete episodes from a central axis. The images also show that this style of tectonic activity involved plates < 10 km across. Although this tectonic style superficially resembles aspects of similar activity on Earth, such as sea-floor spreading and the formation of ice leads in polar seas, there are significant differences in the underlying physical mechanisms: the wedge-shaped bands on Europa most probably formed when lower material (ice or water) rose to fill the fractures that widened in response to regional surface stresses.


Asunto(s)
Júpiter , Fenómenos Geológicos , Geología , Hielo
18.
Science ; 274(5286): 377-85, 1996 10 18.
Artículo en Inglés | MEDLINE | ID: mdl-17813508

RESUMEN

The first images of Jupiter, Io, Europa, and Ganymede from the Galileo spacecraft reveal new information about Jupiter's Great Red Spot (GRS) and the surfaces of the Galilean satellites. Features similar to clusters of thunderstorms were found in the GRS. Nearby wave structures suggest that the GRS may be a shallow atmospheric feature. Changes in surface color and plume distribution indicate differences in resurfacing processes near hot spots on Io. Patchy emissions were seen while Io was in eclipse by Jupiter. The outer margins of prominent linear markings (triple bands) on Europa are diffuse, suggesting that material has been vented from fractures. Numerous small circular craters indicate localized areas of relatively old surface. Pervasive brittle deformation of an ice layer appears to have formed grooves on Ganymede. Dark terrain unexpectedly shows distinctive albedo variations to the limit of resolution.

19.
Science ; 265(5178): 1543-7, 1994 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-17801529

RESUMEN

The first images of the asteroid 243 Ida from Galileo show an irregular object measuring 56-kilometers by 24 kilometers by 21 kilometers. Its surface is rich in geologic features, including systems of grooves, blocks, chutes, albedo features, crater chains, and a full range of crater morphologies. The largest blocks may be distributed nonuniformly across the surface; lineaments and dark-floored craters also have preferential locations. Ida is interpreted to have a substantial regolith. The high crater density and size-frequency distribution (-3 differential power-law index) indicate a surface in equilibrium with saturated cratering. A minimum model crater age for Ida-and therefore for the Koronis family to which Ida belongs-is estimated at 1 billion years, older than expected.

20.
Science ; 264(5162): 1112-5, 1994 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-17744892

RESUMEN

Multispectral images obtained during the Galileo probe's second encounter with the moon reveal the compositional nature of the north polar regions and the northeastern limb. Mare deposits in these regions are found to be primarily low to medium titanium lavas and, as on the western limb, show only slight spectral heterogeneity. The northern light plains are found to have the spectral characteristics of highlands materials, show little evidence for the presence of cryptomaria, and were most likely emplaced by impact processes regardless of their age.

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