Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

A test of desicattion of P. platensis showed a reduction from 70% of the body weight was water to 42% water at death. Mean water loss was 30%, and mean survival time was 43min. Loss of tactile response ocurred at 27% water loss. Mean osmoalality was 0.62 M/Kg.

A preliminary classification of 32 lagoons in Guatemala according physical and chemical water characteristics (cluster analysis) is provided. The water chemistry showed great differences independently of climate, elevation, geology, origin, soil and man’s actions. The statistical analysis defined groups of lagoons that will be continously monitored for further classification and potential acuaculture.

Eunice riojai n. sp., is described from the Caribbean Coast of Mexico based upon one specimen collected among intertidal sponges. This species belongs to the Pantropical fuscus-unidentatus group. It has a peculiar parapodial development and vranchial distribution, Main morphological characters of the species of this group are compared and a key to the group is included.

The amino acid profile was studied in individual random samples of urine from 1147 normal schoolchildren and 1074 exceptional children: 628 with mental retardation, 332 with hearing and speech defects and 114 with visual defects as well as in 673 patients with mental disorders. Laboratory procedures included chemical tests and one-dimension paper- electro- and column-chromatography. Phenylketonuria was found in a mentally retarded girl and in one and in one of her brothers: iminoglycinuria in a mentally retarded boy and heterozygole cystinuria in a man with manic-depressive psychosis. The percentage of high excretors of beta-aminoisobutiric acid (B-AIB) in the controls (4.88%) was similar to previous findings in the Caucasian race. The children with hearing and speech defects showed a number of high excretors of B-AIB significantly lower (X2 = 5.32; p < 0.025) and the children with visual defects a number of hyperglycinurias significantly higher (X2 = 9,19; p <0.05). Previous non-consistent findings on the excess of high excretors of B-AIB in Down’s syndrome were not confirmed in this study. These results suggest a relationship between transport defects in the plasma membrane and pathological dirsorders in some of the cases screened.

This work reports 15 months of phenological observations in a premontane rainforest of Costa Rica. All phenological characteristics display annual periodicity. The peak of leaf flushing occurs during the driest months of the year, but flowering shows two peaks, one m April (dry season) and the other in August (wet season). On the other hand, fruiting and leaf-fall show maximum activity during the wet season. A significative correlation between rainfall and temperature with leaf flushing for the three tree strata was found. Leaf fall and flowering of codominant and dominated trees correlate with rainfall, but this is not true for dominant trees.

During a fish resource survey of Jiquilisco Bay, El Salvador, from September 1975 to November 1976, the three dominant commercially important families were the Ariidae, Gerreidae and Sciaenidae. For combined data, peak capture abundance occurred during the rain y season (May to September) and consisted mainly of pre-adult fishes. Gonadal inspection and occurrence of pre-adults indicated prolonged and variable spawning seasons for most species; only Galeichthys jordani (Ariidae), showed a restricted spawning season with young-of-year peak abundance during the mid-rainy season. The 11 sciaenid species probably do not spawn in this coastal lagoon but use it as a nursery area.

An analysis of 1315 cases of gastric cancer from the records of the Ministry of Public Health, San José, Costa Rica between 1977 and 1980 showed important geographical differences in the incidence, and especially in relation to the sex ratio, age structure and migratory patterns. Rates of incidence ranged between 12.6 and 153.2 per 100,000 inhabitants in men and 10.6 and 56.6 in women. Variations in the incidence of gastric cancer rates were studied in relation to ecological parameters, including certain soil and drinking water characteristics as well as the presence of vitamins A and C in serum. No significant relation was found between gastric cancer rates and the presence of vitamins and of several components in drinking water. However, a multivariate analysis considering nine soil components and pH showed a statistically significant (p< 0.01) association with pH, K, Zn and Fe, which account for 22% of the variation in the incidence rates. A dynamic and multifactorial model is proposed to explain regional variations in cancer rates, with a: tentative application of this model to the results obtained.

The leptocephalus larva of Lycodontis verrilli is identified on the basis of its high vertebral count and anterior position of the anal fin. The larva of this uncommon species is described and illustrated for the first time and compared with other eastern tropical Pacific muraenids.

A new wrasse, Halichoeres discolor, is described from 136 specimens taken at 14 inshore sites at Cocos Island, Costa Rica, the only known locality. The species has a distinctive juvenile color phase that resembles the coloration of juvenile Halichoeres nicholsi from the eastern Pacific mainland. The adult coloration of the new form is dark gray above, yellow-brown be low with blue stripes on the head and forebody and the fins mostly salmon-colored.

Experimental conditions for the comparative measurement of proteolytic activity of Costa Rican snake venoms on casein are established, and the activity of 13 different venoms is described. Venoms showed marked differences in activity not only between species, but between specimens of the same species captured in different geographic regions of Costa Rica.