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1.
Nature ; 577(7792): E9, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31925404

RESUMO

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

2.
Nature ; 568(7752): 382-386, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30962533

RESUMO

Glaciers distinct from the Greenland and Antarctic ice sheets cover an area of approximately 706,000 square kilometres globally1, with an estimated total volume of 170,000 cubic kilometres, or 0.4 metres of potential sea-level-rise equivalent2. Retreating and thinning glaciers are icons of climate change3 and affect regional runoff4 as well as global sea level5,6. In past reports from the Intergovernmental Panel on Climate Change, estimates of changes in glacier mass were based on the multiplication of averaged or interpolated results from available observations of a few hundred glaciers by defined regional glacier areas7-10. For data-scarce regions, these results had to be complemented with estimates based on satellite altimetry and gravimetry11. These past approaches were challenged by the small number and heterogeneous spatiotemporal distribution of in situ measurement series and their often unknown ability to represent their respective mountain ranges, as well as by the spatial limitations of satellite altimetry (for which only point data are available) and gravimetry (with its coarse resolution). Here we use an extrapolation of glaciological and geodetic observations to show that glaciers contributed 27 ± 22 millimetres to global mean sea-level rise from 1961 to 2016. Regional specific-mass-change rates for 2006-2016 range from -0.1 metres to -1.2 metres of water equivalent per year, resulting in a global sea-level contribution of 335 ± 144 gigatonnes, or 0.92 ± 0.39 millimetres, per year. Although statistical uncertainty ranges overlap, our conclusions suggest that glacier mass loss may be larger than previously reported11. The present glacier mass loss is equivalent to the sea-level contribution of the Greenland Ice Sheet12, clearly exceeds the loss from the Antarctic Ice Sheet13, and accounts for 25 to 30 per cent of the total observed sea-level rise14. Present mass-loss rates indicate that glaciers could almost disappear in some mountain ranges in this century, while heavily glacierized regions will continue to contribute to sea-level rise beyond 2100.

3.
Nature ; 454(7205): 735-8, 2008 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-18685701

RESUMO

In cold dark matter cosmological models, structures form and grow through the merging of smaller units. Numerical simulations have shown that such merging is incomplete; the inner cores of haloes survive and orbit as 'subhaloes' within their hosts. Here we report a simulation that resolves such substructure even in the very inner regions of the Galactic halo. We find hundreds of very concentrated dark matter clumps surviving near the solar circle, as well as numerous cold streams. The simulation also reveals the fractal nature of dark matter clustering: isolated haloes and subhaloes contain the same relative amount of substructure and both have cusped inner density profiles. The inner mass and phase-space densities of subhaloes match those of recently discovered faint, dark-matter-dominated dwarf satellite galaxies, and the overall amount of substructure can explain the anomalous flux ratios seen in strong gravitational lenses. Subhaloes boost gamma-ray production from dark matter annihilation by factors of 4 to 15 relative to smooth galactic models. Local cosmic ray production is also enhanced, typically by a factor of 1.4 but by a factor of more than 10 in one per cent of locations lying sufficiently close to a large subhalo. (These estimates assume that the gravitational effects of baryons on dark matter substructure are small.).

4.
Soc Psychiatry Psychiatr Epidemiol ; 24(2): 113-9, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2499052

RESUMO

In order to find out whether the level of Expressed Emotion represents only the emotional engagement of the closest relative, or whether it corresponds to a special sort of relationship between relative and patient, 17 parents of schizophrenic patients were examined with the Camberwell Family Interview and rated as high or low EE. They were also questioned in a semi-structured interview about interactions between themselves and the patient. Transcripts of these reported interactions were analysed and described with an interpersonal instrument (SASB). The comparison of the data from CFI and SASB shows that EE-measures of the parents correlate strongly with certain features of the relationship. High EE relationships have a more negative emotional climate, a conflict-prone structure and especially rigid patterns of interaction. In addition, there were significant correlations between SASB-variables and two subscores of the CFI (criticism and emotional overinvolvement). These results add to the validity of the EE-concept and suggest that EE-measures of relatives correspond with certain qualities of the patient-relative relationship.


Assuntos
Emoções , Relações Pais-Filho , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Psicológicos , Fatores de Risco
5.
J Dairy Sci ; 68(10): 2580-7, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4067036

RESUMO

Blood plasma 3-methylhistidine, in comparison with other blood variables, has been measured in high-yielding dairy cows with relation to energy and protein supply. Circulating 3-methylhistidine markedly increased to 1 wk after calving, then continuously decreased to 5 wk postpartum to lower than during the last 2 wk of pregnancy. In experiments 36 d after calving, circulating 3-methylhistidine did not change during 24 h despite marked variations of food intake. Peak 3-methylhistidine immediately after parturition coincided with relatively low insulin, thyroxine, triiodothyronine, glucose, protein, and urea with elevated concentrations of nonesterified fatty acids and with greatest estimated energy and protein deficiencies. However, during the ensuing period to 12 wk of lactation, circulating 3-methylhistidine was not closely related to these measures nor to creatinine, beta-hydroxybutyrate, and milk production, but relationships to milk protein yield were close. The postparturient increase of 3-methylhistidine may have been a consequence of enhanced breakdown of skeletal muscle and uterine smooth muscle or another pool with a transiently enhanced turnover rate. Variations of plasma 3-methylhistidine were associated only in part with estimated negative energy and protein balances and corresponding endocrine and metabolic adaptations.


Assuntos
Bovinos/sangue , Histidina/análogos & derivados , Metilistidinas/sangue , Período Pós-Parto , Animais , Metabolismo Energético , Feminino , Lactação , Gravidez
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