Micromechanics of sea ice frictional slip from test basin scale experiments.

We have conducted a series of high-resolution friction experiments on large floating saline ice floes in an environmental test basin. In these experiments, a central ice floe was pushed between two other floes, sliding along two interfacial faults. The frictional motion was predominantly stick-slip.

Symptoms of postpartum depression and breastfeeding.

Despite important health benefits, the presence of depressive symptoms may decrease the prevalence of breastfeeding. The current study assessed the relationship between depressive symptoms and breastfeeding at 6 and 12 weeks postpartum. Participants were recruited from a cohort completing a clinical trial of calcium for prevention of preeclampsia.

Repeated daily injections and osmotic pump infusion of isoproterenol cause similar increases in cardiac mass but have different effects on blood pressure.

We found in mice that repeated single daily subcutaneous (s.c.) isoproterenol (ISO) injections, like constant infusions using osmotic minipumps, caused increased biventricular mass or weight relative to body weight (VW/BW).

Gestational calcium supplementation and blood pressure in the offspring.

Background: The current study examined the relationship between calcium supplementation during pregnancy and blood pressure (BP) in the mother and offspring at 3 months and at 2 years postpartum.

Methods: Nulliparous pregnant women were assigned to either receive 2 g of calcium or placebo daily beginning between weeks 13 to 21 of gestation and continuing until delivery. Blood pressure was measured in children and their mothers at 3 months (n = 260) and (n = 57) at 2 years postpartum.

Blood pressure and mesenteric resistance arterial function after spaceflight.

Ground studies indicate that spaceflight may diminish vascular contraction. To examine that possibility, vascular function was measured in spontaneously hypertensive rats immediately after an 18-day shuttle flight. Isolated mesenteric resistance arterial responses to cumulative additions of norepinephrine, acetylcholine, and sodium nitroprusside were measured using wire myography within 17 h of landing.

Calcium metabolism and cardiovascular function after spaceflight.

To determine the influence of dietary calcium on spaceflight-induced alterations in calcium metabolism and blood pressure (BP), 9-wk-old spontaneously hypertensive rats, fed either high- (2%) or low-calcium (0.02%) diets, were flown on an 18-day shuttle flight. On landing, flight animals had increased ionized calcium (P < 0.