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Degradation of coral reef ecosystems began centuries ago, but there is no global summary of the magnitude of change. We compiled records, extending back thousands of years, of the status and trends of seven major guilds of carnivores, herbivores, and architectural species from 14 regions. Large animals declined before small animals and architectural(More)
Estuarine and coastal transformation is as old as civilization yet has dramatically accelerated over the past 150 to 300 years. Reconstructed time lines, causes, and consequences of change in 12 once diverse and productive estuaries and coastal seas worldwide show similar patterns: Human impacts have depleted >90% of formerly important species, destroyed(More)
Mitochondrial DNA (mtDNA) haplotype diversity was determined for 46 Ngöbé Amerinds sampled widely across their geographic range in western Panamá. The Ngöbé data were compared with mtDNA control region I sequences from two additional Amerind groups located at the northern and southern extremes of Amerind distribution, the Nuu-Chah-Nulth of the Pacific(More)
The Central American isthmus was a major dispersal route for plant taxa originally brought under cultivation in the domestication centers of southern Mexico and northern South America. Recently developed methodologies in the archaeological and biological sciences are providing increasing amounts of data regarding the timing and nature of these dispersals(More)
Metaldehyde when administered orally to mice at a dose of 1 g kg-1 produced convulsions and death within 2 h. Brain concentrations of gamma-aminobutyric acid (GABA) were significantly reduced and monoamine oxidase (MAO) activity significantly increased in these animals relative to controls. Treatment with either intraperitoneal diazepam or clonidine 20 min(More)
The disappearance of oxytocin from the peripheral circulation of the goat after a single intravenous injection followed a biexponential curve. The mean (+/- SD) half-life, calculated from the slower component of this decline, was 22.3 +/- 0.6 minutes. The volume of the central compartment was about twice the volume of the vascular compartment and the total(More)
Chili peppers (Capsicum spp.) are widely cultivated food plants that arose in the Americas and are now incorporated into cuisines worldwide. Here, we report a genus-specific starch morphotype that provides a means to identify chili peppers from archaeological contexts and trace both their domestication and dispersal. These starch microfossils have been(More)
Doses of 0.005-1.0 mg of ACTH1-24 given intravenously, intramuscularly or as an intramuscular depot injection caused increases in cortisol concentrations within 15 min in the plasma of ewes. There was, however, considerable animal-to-animal variation in maximum concentrations achieved. A curvilinear dose-response relationship to ACTH1-24 was obtained which(More)
Active immunization against oxytocin significantly prolonged the oestrous cycle in 3 out of 4 goats; the mean (+/- s.e.m.) cycle length was 29.1 +/- 1.7 days (n = 12) compared to 19.4 +/- 0.6 days (n = 9) in control animals. During Days 10-21 of the cycle in the 3 responsive goats, peripheral plasma concentrations of progesterone and oxytocin were steady(More)
Peripheral plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) and progesterone were determined during both luteolysis in the oestrous cycle and early pregnancy in four goats. Luteal regression, characterised by decreasing progesterone concentrations, began on day 12 or 13. PGFM concentrations showed a pulsatile pattern around this(More)