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New uvby–βdata are provided for 442 high-velocity and metal-poor stars; 90 of these stars have been observed previously by us, and 352 are new. When combined with our previous two photometric catalogues, the data base is now made up of 1533 high-velocity and metal-poor stars, all with uvby–βphotometry and complete kinematic data, such as proper motions and radial velocities taken from the literature. Hipparcos, plus a new photometric calibration for Mvalso based on the Hipparcos parallaxes, provide distances for nearly all of these stars; our previous photometric calibrations give values for $E(b-y)$and [Fe/H]. The [Fe/H], V(rot) diagram allows us to separate these stars into different Galactic stellar population groups, such as old-thin-disk, thick-disk, and halo. The Xhistogram, where Xis our stellar-population discriminator combining V(rot) and [Fe/H], and contour plots for the [Fe/H], V(rot) diagram both indicate two probable components to the thick disk. These population groups and Galactic components are studied in the $(b-y)_{0}$, Mvdiagram, compared to the isochrones of Bergbusch & VandenBerg (2001, ApJ, 556, 322), to derive stellar ages. The two thick-disk groups have the mean characteristics: ([Fe/H], V(rot), Age, $\sigma_{W'}) \approx (-0.7$dex, 120 km s-1, 12.5 Gyr, 62.0 km s-1), and ${\approx}$(-0.4, 160, 10.0, 45.8). The seven most metal-poor halo groups, $-2.31 \leq [$Fe/H$] \leq -1.31$, show a mean age of $13.0 \pm 0.2$(mean error) Gyr, giving a mean difference from the WMAP results for the age of the Universe of $0.7 \pm 0.3$Gyr. These results for the ages and components of the thick disk and for the age of the Galactic halo field stars are discussed in terms of various models and ideas for the formation of galaxies and their stellar populations.

A survey on goiter was carried out in Pedregoso, an isolated Indian Reservation in the Chilean Andes. A palpable goitre was present in 84 per cent of the adult population. All subjects were clinically euthyroid and had a normal contraction time of the Achilles tendon reflex. The mean value for serum PBI was 5.06 μg/100 ml, with 22% of the cases having values below 4 μg. Iodine deficiency was established by its low concentration in drinking water (0.35 μg/liter) and in the urine (33 μg/24 h).Radioiodine studies showed an average thyroid uptake of 68% at 24 h with a tendency to increase directly with thyroid size and to decrease with age. Serum labelled PBI reflected different radioiodine turnover rates, highest values being more frequent in large nodular goitres. Triiodothyronine (T3) suppression tests were negative in about one-third of the goitrous subjects. Perchlorate tests and antithyroid antibodies determinations consistently gave negative results.Thyroxine (T4) was always the main labelled compound, T3being significantly present in 9 out of 22 cases. Up to 18% of the circulating radioiodine at 48 h was not butanol-extractable, and appeared in the initial fraction of column chromatography analysis. Six out of 58 cases also showed endogenously labelled diiodotyrosine (DIT), which constituted up to 10% of the total circulating radioiodine at 48 h. After intravenous injection of a tracer dose labelled DIT, 5.8 per cent ± 0.51 of the dose was excreted unchanged in the urine within 2 h. The highest values were observed in the largest goitres.The extra-thyroid organic iodine compartment was investigated after the injection of labelled T4and T3. An increase in fractional turnover rate was always observed associated with an increase in the thyroxine distribution space.