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1.
BMC Public Health ; 19(1): 403, 2019 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-30987623

RESUMEN

BACKGROUND: English Stop Smoking Services primarily deliver behavioural interventions to support abrupt quit attempts. Recent evidence suggests an alternative approach could be offered to clients involving a more gradual reduction of cigarettes smoked leading to complete abstinence, known as 'Cut Down To Stop' (CDTS). The purpose of this study was to explore the experiences of stop smoking practitioners and service users who participated in a pilot study of a CDTS service. METHODS: The CDTS intervention was pilot tested in a Stop Smoking Service in London, England. As part of the CDTS intervention clients who were still smoking 2 weeks after their quit date were offered tailored advice, medication and support to reduce their current smoking by half, with the aim to stop smoking altogether within a six-month period. A qualitative evaluation was conducted involving a focus group discussion with nine practitioners involved in the delivery of the CDTS intervention and telephone interviews with 18 CDTS service users. Thematic analysis was performed. RESULTS: Service users and practitioners were very positive about their experience with the CDTS intervention. The intervention was found to be an effective way of keeping clients engaged with the service and was felt to increase the likelihood they might quit and/or re-engage in service for future quit attempts. Elements that contributed to the attractiveness of the CDTS intervention included: 1) the trust and empathetic relationship developed between service users, practitioners and their referring primary care provider; 2) time and flexibility for service users to engage in the quitting process at their own pace; 3) setting progressive goals and building service user confidence; 4) the opportunity to experiment with quit smoking medications; and, 5) the on-going contact with the practitioner/service. CONCLUSIONS: Service users who are not successful with quitting abruptly may benefit from a CDTS intervention. This study highlights the important role of 'relationships', time and 'flexible' service delivery models in engaging service users who are not initially successful with quitting. The findings of this study have the potential to inform decision-making regarding the value of the CDTS approach for the English Stop Smoking Service and cessation services worldwide.


Asunto(s)
Terapia Conductista/métodos , Conductas Relacionadas con la Salud , Fumadores/psicología , Cese del Hábito de Fumar/métodos , Fumar/psicología , Adulto , Inglaterra , Femenino , Humanos , Londres , Masculino , Persona de Mediana Edad , Proyectos Piloto , Derivación y Consulta
2.
Br J Cancer ; 112(11): 1799-804, 2015 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-25950385

RESUMEN

BACKGROUND: Smoking cessation is the key cancer prevention behaviour for smokers; nonetheless, smokers can still benefit from earlier diagnosis of cancer. However, fewer smokers participate in screening despite their increased risk, which may reflect different beliefs about cancer. METHODS: A UK population-representative sample of ⩾50 year-olds (n=6965) was surveyed using the Awareness and Beliefs about Cancer measure. These analyses examine six items on cancer beliefs (e.g., 'cancer can often be cured'), and four on help-seeking barriers (e.g., 'I would be too embarrassed'). RESULTS: Smokers were more likely to hold pessimistic cancer beliefs than never-smokers or former-smokers on four of six items. For example, 34% agreed 'a cancer diagnosis is a death sentence', compared with 24% of non/former-smokers (P<0.001). More smokers (18%) than non/former-smokers (11%) would not want to know if they had cancer (P<0.01). The only barrier to symptomatic help-seeking differing by smoking status was 'worry about what the doctor might find' (36% vs 28%, P<0.01). Associations were independent of demographics, self-rated health and cancer experience. CONCLUSIONS: Smokers held more pessimistic and avoidant beliefs about cancer, which could deter early-detection behaviour. A better understanding of these beliefs is needed to increase engagement in early diagnosis by this high-risk group.


Asunto(s)
Actitud Frente a la Salud , Detección Precoz del Cáncer , Neoplasias Pulmonares/psicología , Fumar/efectos adversos , Anciano , Femenino , Humanos , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Riesgo , Fumar/psicología
3.
Nature ; 448(7149): 50-3, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17611535

RESUMEN

Hyperion is Saturn's largest known irregularly shaped satellite and the only moon observed to undergo chaotic rotation. Previous work has identified Hyperion's surface as distinct from other small icy objects but left the causes unsettled. Here we report high-resolution images that reveal a unique sponge-like appearance at scales of a few kilometres. Mapping shows a high surface density of relatively well-preserved craters two to ten kilometres across. We have also determined Hyperion's size and mass, and calculated the mean density as 544 +/- 50 kg m(-3), which indicates a porosity of >40 per cent. The high porosity may enhance preservation of craters by minimizing the amount of ejecta produced or retained, and accordingly may be the crucial factor in crafting this unusual surface.

4.
J Genet Couns ; 22(6): 875-84, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23355075

RESUMEN

The development of standards for training and certification is essential to the credibility and integrity of a developing profession. Training and certification of genetic counselors in Australasia has undergone a detailed review during the past few years, resulting in changes to the way certification is obtained. This paper presents an overview of the process of developing a robust training and certification program which reflects the social and cultural environment of genetic counselors working in Australasia. A brief history of the development of the profession in Australasia is provided, followed by a detailed discussion of the recent development of Masters programs and a portfolio of work required for certification. The importance of consultation within the profession and with our colleagues in the field of human genetics is considered, and we provide a discussion of defining moments that occurred during the review. This paper is intended to provide a detailed description of genetic counselor training and certification in Australasia. We anticipate that our insights into the process of redevelopment of training and certification guidelines may be helpful for genetic counselors working in countries where certification requirements are being developed.


Asunto(s)
Certificación , Educación Profesional/organización & administración , Asesoramiento Genético , Australasia , Revelación , Humanos , Competencia Profesional
5.
Psychoneuroendocrinology ; 133: 105382, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34419762

RESUMEN

Very little is known about maternal cerebral changes during pregnancy. Since there is an increased risk for major depression during pregnancy and postpartum, it is important to understand the structural and neurochemical changes that occur in the brain during pregnancy. Using proton magnetic resonance spectroscopy (1H-MRS) (3 T field strength), glutamate (Glu) levels were measured in the medial prefrontal cortex (MPFC) of 21 healthy gravid subjects 2-3 weeks before their due date (6.74 ± 1.39), and in 14 non-pregnant healthy controls during their follicular phase (8.53 ± 1.55). Water quantified MPFC Glu levels were decreased in pregnant women (p < 0.01). We also observed a 13.9% decrease in percentage grey matter (%GM) (p < 0.01) in our MPFC voxel. As Glu is mostly found in GM, we repeated the statistical analysis after adjustment for %GM and found that the difference in Glu levels was no longer statistically significant when adjusted for %GM (p = 0.10). This investigation is the only systematic direct investigation of brain tissue composition and Glu levels in pregnant women. The main finding of this investigation is the decreased %GM in healthy pregnant women compared to non-pregnant women. These findings of decreased %GM in pregnancy may be responsible for the frequent complaints by pregnant women of cognitive difficulties also described as pregnesia.


Asunto(s)
Ácido Glutámico , Corteza Prefrontal , Estudios de Casos y Controles , Femenino , Ácido Glutámico/metabolismo , Humanos , Corteza Prefrontal/metabolismo , Embarazo , Mujeres Embarazadas , Espectroscopía de Protones por Resonancia Magnética
6.
Sci Adv ; 7(6)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33536216

RESUMEN

On Mars, seasonal martian flow features known as recurring slope lineae (RSL) are prevalent on sun-facing slopes and are associated with salts. On Earth, subsurface interactions of gypsum with chlorides and oxychlorine salts wreak havoc: instigating sinkholes, cave collapse, debris flows, and upheave. Here, we illustrate (i) the disruptive potential of sulfate-chloride reactions in laboratory soil crust experiments, (ii) the formation of thin films of mixed ice-liquid water "slush" at -40° to -20°C on salty Mars analog grains, (iii) how mixtures of sulfates and chlorine salts affect their solubilities in low-temperature environments, and (iv) how these salt brines could be contributing to RSL formation on Mars. Our results demonstrate that interactions of sulfates and chlorine salts in fine-grained soils on Mars could absorb water, expand, deliquesce, cause subsidence, form crusts, disrupt surfaces, and ultimately produce landslides after dust loading on these unstable surfaces.

7.
Earth Space Sci ; 7(10): e2020EA001248, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33134434

RESUMEN

Knowing precisely where a spacecraft lands on Mars is important for understanding the regional and local context, setting, and the offset between the inertial and cartographic frames. For the InSight spacecraft, the payload of geophysical and environmental sensors also particularly benefits from knowing exactly where the instruments are located. A ~30 cm/pixel image acquired from orbit after landing clearly resolves the lander and the large circular solar panels. This image was carefully georeferenced to a hierarchically generated and coregistered set of decreasing resolution orthoimages and digital elevation models to the established positive east, planetocentric coordinate system. The lander is located at 4.502384°N, 135.623447°E at an elevation of -2,613.426 m with respect to the geoid in Elysium Planitia. Instrument locations (and the magnetometer orientation) are derived by transforming from Instrument Deployment Arm, spacecraft mechanical, and site frames into the cartographic frame. A viewshed created from 1.5 m above the lander and the high-resolution orbital digital elevation model shows the lander is on a shallow regional slope down to the east that reveals crater rims on the east horizon ~400 m and 2.4 km away. A slope up to the north limits the horizon to about 50 m away where three rocks and an eolian bedform are visible on the rim of a degraded crater rim. Azimuths to rocks and craters identified in both surface panoramas and high-resolution orbital images reveal that north in the site frame and the cartographic frame are the same (within 1°).

8.
Science ; 250(4979): 421-4, 1990 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-17793018

RESUMEN

Aeolian features on Triton that were imaged during the Voyager Mission have been grouped. The term "aeolian feature" is broadly defined as features produced by or blown by the wind, including surface and airborne materials. Observations of the latitudinal distributions of the features probably associated with current activity (known plumes, crescent streaks, fixed terminator clouds, and limb haze with overshoot) all occur from latitude -37 degrees to latitude -62 degrees . Likely indicators of previous activity (dark surface streaks) occur from latitude -5 degrees to -70 degrees , but are most abundant from -15 degrees to -45 degrees , generally north of currently active features. Those indicators which give information on wind direction and speed have been measured. Wind direction is a function of altitude. The predominant direction of the surface wind streaks is found to be between 40 degrees and 80 degrees measured clockwise from north. The average orientation of streaks in the northeast quadrant is 59 degrees . Winds at 1- to 3- kilometer altitude are eastward, while those at &8 kilometers blow west.

9.
Science ; 288(5469): 1204-8, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10817989

RESUMEN

Unlike any volcanic behavior ever observed on Earth, the plume from Prometheus on Io has wandered 75 to 95 kilometers west over the last 20 years since it was first discovered by Voyager and more recently observed by Galileo. Despite the source motion, the geometric and optical properties of the plume have remained constant. We propose that this can be explained by vaporization of a sulfur dioxide and/or sulfur "snowfield" over which a lava flow is moving. Eruption of a boundary-layer slurry through a rootless conduit with sonic conditions at the intake of the melted snow can account for the constancy of plume properties.


Asunto(s)
Júpiter , Erupciones Volcánicas , Frío , Entropía , Medio Ambiente Extraterrestre , Calor , Hielo , Modelos Químicos , Nieve , Nave Espacial
10.
Science ; 266(5192): 1858-62, 1994 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-17737082

RESUMEN

Multispectral and topographic data acquired by the Clementine spacecraft provide information on the composition and geologic history of the Aristarchus region of the moon. Altimetry profiles show the Aristarchus plateau dipping about 1 degrees to the north-northwest and rising about 2 kilometers above the surrounding lavas of Oceanus Procellarum to the south. Dark, reddish pyroclastic glass covers the plateau to average depths of 10 to 30 meters, as determined from the estimated excavation depths of 100- to 1000-meter-diameter craters that have exposed materials below the pyroclastics. These craters and the walls of sinuous rilles also show that mare basalts underlie the pyroclastics across much of the plateau. Near-infrared images of Aristarchus crater reveal olivine-rich materials and two kilometer-sized outcrops of anorthosite in the central peaks. The anorthosite could be either a derivative of local magnesium-suite magmatism or a remnant of the ferroan anorthosite crust that formed over the primordial magma ocean.

11.
Science ; 288(5469): 1198-201, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10817987

RESUMEN

Galileo's photopolarimeter-radiometer instrument mapped Io's thermal emission during the I24, I25, and I27 flybys with a spatial resolution of 2.2 to 300 kilometers. Mapping of Loki in I24 shows uniform temperatures for most of Loki Patera and high temperatures in the southwest corner, probably resulting from an eruption that began 1 month before the observation. Most of Loki Patera was resurfaced before I27. Pele's caldera floor has a low temperature of 160 kelvin, whereas flows at Pillan and Zamama have temperatures of up to 200 kelvin. Global maps of nighttime temperatures provide a means for estimating global heat flow.


Asunto(s)
Calor , Júpiter , Vuelo Espacial , Erupciones Volcánicas , Oscuridad , Medio Ambiente Extraterrestre , Filtración , Fotometría , Luz Solar
12.
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
13.
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
14.
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.

15.
Science ; 255(5044): 570-6, 1992 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-17792379

RESUMEN

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.

16.
Science ; 257(5077): 1647-52, 1992 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-17841160

RESUMEN

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.

17.
Science ; 288(5469): 1201-4, 2000 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-10817988

RESUMEN

Infrared spectral images of Jupiter's volcanic moon Io, acquired during the October and November 1999 and February 2000 flybys of the Galileo spacecraft, were used to study the thermal structure and sulfur dioxide distribution of active volcanoes. Loki Patera, the solar system's most powerful known volcano, exhibits large expanses of dark, cooling lava on its caldera floor. Prometheus, the site of long-lived plume activity, has two major areas of thermal emission, which support ideas of plume migration. Sulfur dioxide deposits were mapped at local scales and show a more complex relationship to surface colors than previously thought, indicating the presence of other sulfur compounds.


Asunto(s)
Júpiter , Nave Espacial , Erupciones Volcánicas , Medio Ambiente Extraterrestre , Calor , Espectroscopía Infrarroja Corta/métodos , Luz Solar , Temperatura
18.
Science ; 279(5357): 1681-5, 1998 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-9497280

RESUMEN

High-resolution images of the martian surface at scales of a few meters show ubiquitous erosional and depositional eolian landforms. Dunes, sandsheets, and drifts are prevalent and exhibit a range of morphology, composition (inferred from albedo), and age (as seen in occurrences of different dune orientations at the same location). Steep walls of topographic depressions such as canyons, valleys, and impact craters show the martian crust to be stratified at scales of a few tens of meters. The south polar layered terrain and superposed permanent ice cap display diverse surface textures that may reflect the complex interplay of volatile and non-volatile components. Low resolution regional views of the planet provide synoptic observations of polar cap retreat, condensate clouds, and the lifecycle of local and regional dust storms.


Asunto(s)
Medio Ambiente Extraterrestre , Marte , Dióxido de Carbono , Hielo , Nave Espacial
19.
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.

20.
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
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