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1.
Health Econ ; 26(3): 292-304, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-26676999

RESUMO

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.


Assuntos
Comitês Consultivos/estatística & dados numéricos , Longevidade , Classe Social , Comitês Consultivos/tendências , China , Países em Desenvolvimento , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Política
2.
Plant Dis ; 101(8): 1489-1499, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30678581

RESUMO

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.


Assuntos
Patologia Vegetal , Vírus de Plantas , Viroides , Frutas/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Vírus de Plantas/genética , Viroides/genética
3.
Ir Med J ; 104(4): 105-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21675091

RESUMO

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.


Assuntos
Cuidados no Lar de Adoção , Necessidades e Demandas de Serviços de Saúde , Serviços de Saúde Mental , Instituições Residenciais , Adolescente , Criança , Filho de Pais com Deficiência , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Irlanda , Masculino , Psicologia da Criança , Adulto Jovem
4.
Science ; 230(4731): 1229-36, 1985 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-17835960

RESUMO

Halley's comet is the focus of an international scientific enterprise now under way. Ground-based astronomical observations are already yielding new information about the comet's nucleus and atmosphere. In the coming year, remote and in situ investigations from the ground, Earth orbit, Venus orbit, interplanetary space, and within the comet itself are expected to reveal much more. The climax of the enterprise will be the penetration of an armored European spacecraft into the center of the comet in March 1986.

5.
Science ; 166(3902): 225-7, 1969 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-17731487

RESUMO

Observations of the martian carbon dioxide band at 1.05 microns made with a three-channel multislit spectrophotometer indicate gross height variations in the vicinity of Syrtis Major and surrounding desert regions. Syrtis Major appears to be very high with essentially no detectable carbon dioxide above it. The data appear to confirm local trends and, in magnitude at least, the large variations of height found in earlier radar observations. A one-to-one correlation of height with albedo is not evident in the results. Elevated areas are found in both desert and dark regions. In several regions dark areas are associated with relatively steep slopes.

6.
Science ; 183(4131): 1315-8, 1974 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-17791374

RESUMO

An objective grating spectrometer on Mariner 10 has measured air-glow in the wavelength range 200 to 1700 angstroms. The data reveal the presence of significant concentrations of hydrogen, helium, carbon, and oxygen atoms in the upper atmosphere of Venus. A preliminary analysis of the hydrogen data indicates an exospheric temperature of 400 degrees K. There is evidence for intense air-glow emission at wavelengths longward of 1350 angstroms; the nature of this emission is unclear, but the radiation is spatially extensive and detectable on both day and night sides of the planet.

7.
Science ; 185(4146): 166-9, 1974 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-17810510

RESUMO

Analysis of data obtained by the ultraviolet experiment on Mariner 10 indicates that Mercury is surrounded by a thin atmosphere consisting in part of helium. The partial pressure of helium at the terminator is about 5 x 10(-12) millibar. The total surface pressure of the atmosphere is less than about 2 x 10(-9) millibar. Upper limits are set for the abundance of various gases, including hydrogen, oxygen, carbon, argon, neon, and xenon. The wavelength dependence of Mercury's surface albedo is similar to that of the moon over a broad range of wavelengths from 500 to 1600 angstroms. Strong signals were recorded by the airglow instrument as Mariner 10 passed through the cavity behind Mercury. They are as yet unexplained but may provide information on the properties of the local plasma.

8.
Science ; 285(5429): 870-4, 1999 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-10436151

RESUMO

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.


Assuntos
Meio Ambiente Extraterreno , Júpiter , Oxigênio , Dióxido de Enxofre , Atmosfera , Sódio
9.
Science ; 184(4135): 459-61, 1974 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-17736516

RESUMO

Mercury has a heavily cratered surface cotntaining basins up to at least 1300 kilometers diameter flooded with mare-like material. Many features are closely similar to those on the moon, but significant structural differences exist. Major chemical differentiation before termination of accretion is implied.

10.
Science ; 183(4131): 1307-15, 1974 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-17791373

RESUMO

The Mariner 10 television camieras imaged the planet Venus in the visible and near ultraviolet for a period of 8 days at resolutions ranging from 100 meters to 130 kilometers. Tle general pattern of the atmospheric circulation in the upper tropospheric/lower stratospheric region is displayed in the pictures. Atmospheric flow is symmetrical between north and south hemispheres. The equatorial motions are zonal (east-west) at approxiimnately 100 meters per second, consistent with the previously inferred 4-day retrograde rotation. Angular velocity increases with latitude. The subsolar region, and the region downwind from it, show evidence of large-scale convection that persists in spite of the main zonal motion. Dynamical interaction between the zonal motion and the relatively stationary region of convection is evidenced by bowlike waves.

11.
Science ; 185(4146): 169-79, 1974 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-17810511

RESUMO

The surface morphology and optical properties of Mercury resemble those of the moon in remarkable detail and record a very similar sequence of events. Chemical and mineralogical similarity of the outer layers of Mercury and the moon is implied; Mercury is probably a differentiated planet with a large iron-rich core. Differentiation is inferred to have occurred very early. No evidence of atmospheric modification of landforms has been found. Large-scale scarps and ridges unlike lunar or martian features may reflect a unique period of planetary compression near the end of heavy bombardment by small planetesimals.

12.
Science ; 281(5373): 87-90, 1998 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9651251

RESUMO

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.


Assuntos
Meio Ambiente Extraterreno , Júpiter , Silicatos , Temperatura Alta , Minerais , Espectrofotometria Infravermelho , Erupções Vulcânicas
13.
Science ; 253(5027): 1531-6, 1991 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-17784096

RESUMO

Images of Venus taken at 418 (violet) and 986 [near-infrared (NIR)] nanometers show that the morphology and motions of large-scale features change with depth in the cloud deck. Poleward meridional velocities, seen in both spectral regions, are much reduced in the NIR In the south polar region the markings in the two wavelength bands are strongly anticorrelated. The images follow the changing state of the upper cloud layer downwind of the subsolar point, and the zonal flow field shows a longitudinal periodicity that may be coupled to the formation of large-scale planetary waves. No optical lightning was detected.

14.
Science ; 206(4421): 962-6, 1979 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-17733915

RESUMO

Extreme ultraviolet spectral observations of the Jovian planetary system made during the Voyager 2 encounter have extended our knowledge of many of the phenomena and physical processes discovered by the Voyager 1 ultraviolet spectrometer. In the 4 months between encounters, the radiation from Io's plasma torus has increased in intensity by a factor of about 2. This change was accompanied by a decrease in plasma temperature of about 30 percent. The high-latitude auroral zones have been positively associated with the magnetic projection of the plasma torus onto the planet. Emission in molecular hydrogen bands has been detected from the equatorial regions of Jupiter, indicating planetwide electron precipitation. Hydrogen Lyman alpha from the dark side of the planet has been measured at an intensity of about 1 kilorayleigh. An observation of the occultation of alpha Leonis by Jupiter was carried out successfully and the data are being analyzed in detail.

15.
Science ; 204(4396): 979-82, 1979 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17800434

RESUMO

Observations of the optical extreme ultraviolet spectrum of the Jupiter planetary system during the Voyager 1 encounter have revealed previously undetected physical processes of significant proportions. Bright emission lines of S III, S IV, and O III indicating an electron temperature of 10(5) K have been identified in preliminary analyses of the Io plasma torus spectrum. Strong auroral atomic and molecular hydrogen emissions have been observed in the polar regions of Jupiter near magnetic field lines that map the torus into the atmosphere of Jupiter. The observed resonance scattering of solar hydrogen Lyman alpha by the atmosphere of Jupiter and the solar occultation experiment suggest a hot thermosphere (>/= 1000 K) wvith a large atomic hydrogen abundance. A stellar occultation by Ganymede indicates that its atmosphere is at most an exosphere.

16.
Science ; 265(5178): 1543-7, 1994 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-17801529

RESUMO

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.

17.
Science ; 255(5044): 570-6, 1992 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-17792379

RESUMO

Multispectral images of the lunar western limb and far side obtained from Galileo reveal the compositional nature of several prominent lunar features and provide new information on lunar evolution. The data reveal that the ejecta from the Orientale impact basin (900 kilometers in diameter) lying outside the Cordillera Mountains was excavated from the crust, not the mantle, and covers pre-Orientale terrain that consisted of both highland materials and relatively large expanses of ancient mare basalts. The inside of the far side South Pole-Aitken basin (>2000 kilometers in diameter) has low albedo, red color, and a relatively high abundance of iron- and magnesium-rich materials. These features suggest that the impact may have penetrated into the deep crust or lunar mantle or that the basin contains ancient mare basalts that were later covered by highlands ejecta.

18.
Science ; 257(5077): 1647-52, 1992 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-17841160

RESUMO

Galileo images of Gaspra reveal it to be an irregularly shaped object (19 by 12 by 11 kilometers) that appears to have been created by a catastrophic collisional disruption of a precursor parent body. The cratering age of the surface is about 200 million years. Subtle albedo and color variations appear to correlate with morphological features: Brighter materials are associated with craters especially along the crests of ridges, have a stronger 1-micrometer absorption, and may represent freshly excavated mafic materials; darker materials exhibiting a significantly weaker 1-micrometer absorption appear concentrated in interridge areas. One explanation of these patterns is that Gaspra is covered with a thin regolith and that some of this material has migrated downslope in some areas.

19.
Science ; 288(5469): 1193-8, 2000 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-10817986

RESUMO

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.


Assuntos
Meio Ambiente Extraterreno , Júpiter , Voo Espacial , Erupções Vulcânicas , Fenômenos Geológicos , Geologia , Aumento da Imagem , Espectrofotometria Infravermelho
20.
Science ; 264(5162): 1112-5, 1994 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-17744892

RESUMO

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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