Most large (over a kilometre in diameter) near-Earth asteroids are now known, but recognition that airbursts (or fireballs resulting from nuclear-weapon-sized detonations of meteoroids in the atmosphere) have the potential to do greater damage than previously thought has shifted an increasing portion of the residual impact risk (the risk of impact from an unknown object) to smaller objects. Above the threshold size of impactor at which the atmosphere absorbs sufficient energy to prevent a ground impact, most of the damage is thought to be caused by the airburst shock wave, but owing to lack of observations this is uncertain. Here we report an analysis of the damage from the airburst of an asteroid about 19 metres (17 to 20 metres) in diameter southeast of Chelyabinsk, Russia, on 15 February 2013, estimated to have an energy equivalent of approximately 500 (±100) kilotons of trinitrotoluene (TNT, where 1 kiloton of TNT = 4.
View Article and Find Full Text PDFObjective: Menorrhagia is defined in terms of statistical"abnormality"as blood loss of >80 mL. We examined the usefulness of this definition in women who were referred to gynecology clinics with heavy periods.
Study Design: A questionnaire survey of 952 menstrual complaint referrals at 3 hospital gynaecology clinics in Glasgow and Edinburgh included 226 women with heavy periods who had also consented to the measurement of their blood loss.
Objective: Menorrhagia is defined as blood loss of >80 mL, but in routine clinical practice measurement is seldom undertaken. Our aim was to identify the features of the clinical history that best predict menorrhagic blood loss.
Study Design: A questionnaire survey of 952 menstrual complaint referrals at 3 hospital gynecology clinics in Glasgow and Edinburgh included 226 women with putatively heavy periods who also had consented to the measurement of their blood loss.
Recent studies have linked maternal consumption of an unbalanced high-protein, low-carbohydrate diet in late pregnancy with raised adult blood pressure in the offspring. Because high-protein diets stimulate the hypothalamic-pituitary-adrenal axis, we hypothesized that an unbalanced maternal diet might increase maternal cortisol levels, exposing the fetus to excess cortisol and programming lifelong hypersecretion of cortisol. We therefore measured fasting plasma cortisol concentrations in 251 subjects, 28-30 yr old, whose mothers had been advised to eat 0.
View Article and Find Full Text PDFTo examine the hypothesis that a high-animal protein, low-carbohydrate diet in pregnancy is associated with raised blood pressure in the adult offspring, we performed a follow-up study of 626 men and women in Motherwell, Scotland, whose mothers' food intake had been recorded during pregnancy. The mothers had taken part in a dietary intervention in which they were advised to eat 1 lb (0.45 kg) of red meat per day and to avoid carbohydrate-rich foods during pregnancy.
View Article and Find Full Text PDF