988 resultados para Nature - French romance


Relevância:

20.00% 20.00%

Publicador:

Resumo:

We report the discovery of a periodic modulation in the optical lightcurve of the candidate ultracompact X-ray binary 4U 1822-000. Using time-resolved optical photometry taken with the William Herschel Telescope we find evidence for a sinusoidal modulation with a semi-amplitude of 8 per cent and a period of 191 min, which is most likely close to the true orbital period of the binary. Using the van Paradijs & McClintock relation for the absolute magnitude and the distance modulus allowing for interstellar reddening, we estimate the distance to 4U 1822-000 to be 6.3 kpc. The long orbital period casts severe doubts on the ultracompact nature of 4U 1822-000.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Hypertension is a key risk factor for stroke, cardiovascular disease and dementia. Although the link between weight, sodium and hypertension is established in younger people, little is known about their inter-relationship in people beyond 80 years of age. Associations between blood pressure, anthropometric indices and sodium were investigated in 495 apparently healthy, community-living participants (age 90, SD 4.8; range 80–106), from the cross-sectional Belfast Elderly Longitudinal Free-living Aging STudy (BELFAST) study. In age-sex-adjusted logistic regression models, blood pressure =140/90 mmHg significantly associated with body mass index (BMI) [odds ratio (OR)?=?1.28/ kg/m2], with weight (OR?=?1.22/kg) approaching significance (P?=?0.07). In further age-sex-adjusted models, blood pressure above the 120/80 mmHg normotensive reference value significantly associated with BMI (OR?=?1.44/kg/m2), weight (OR?=?1.36/kg), skin-fold-thickness (OR?=?1.33/mm) and serum sodium (OR?=?1.37 mmol/l). In BELFAST participants over 80 years old, blood pressure =140/90 mmHg is associated with BMI, in apparently similar ways to younger groups.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

KF, LiF and CsF/A(2)O(3) catalysts with different loadings from 1 to 20 wt% were prepared using aqueous solutions of the alkaline fluoride compounds by wet impregnation of basic mesoporous MSU-type alumina. The catalysts were activated under At at 400 degrees C for 2 h and monitored by in situ XRD measurements. The catalysts were also characterized using several techniques: N-2 adsorption/desorption isotherms at -196 degrees C, FTIR, DR-UV-vis, CO2-TPD, XRD, Al-27 CP/MAS NMR. These characterizations led to the conclusion that the deposition of alkaline fluorides on the alumina surface generates fluoroaluminates and aluminate species. The process is definitivated at 400 degrees C. The fluorine in these structures is less basic than in the parent fluorides, but the oxygen becomes more basic. The catalysts were tested for the transesterification of fatty esters under different experimental conditions using conventional heating, microwave and Ultrasound irradiation. Recycling experiments showed that these catalysts are stable for a limited number of cycles. (C) 2009 Elsevier Inc. All rights reserved.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This essay examines Norman Mailer's theory of the "commando raid" shooting style that guided his film MAIDSTONE (1970). Mailer's own published commentary is compared with the various narrative and aesthetic concessions he had to make during both the highly-improvised production phase and the tightly-controlled post-production phase.

Relevância:

20.00% 20.00%

Publicador:

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This article compares chronologies reconstructed from historical records of prices, wages, grain harvests, and population with corresponding chronologies of growing conditions and climatic variations derived from dendrochronology and Greenland ice-cores. It demonstrates that in pre-industrial, and especially late medieval, England, short-term environmental shocks and more enduring shifts in environmental conditions (sometimes acting in concert with biological agencies) exercised a powerful influence upon the balance struck between population and available resources via their effects upon the reproduction, health and life expectancy of humans, crops, and livestock. Prevailing socio-economic conditions and institutions, in turn, shaped society's susceptibility to these environmental shocks and shifts.

Relevância:

20.00% 20.00%

Publicador: