Biological consequences of the 1975 el nino

The weak El Ni?o event of 1975 had a clearly defined effect on the biological productivity of the southeastern tropical Pacific. During February and March 1975, warm (27 degrees C) water of low salinity (33.5 parts per thousand) and low nutrient content extended south across the equator east of the Galápagos Islands, replacing the nutrient-rich water normally supplied by equatorial upwelling. Equatorial primary production was less than 0.2 gram of carbon per square meter per day, one-fifth of the normal value. At the maximum development of the 1975 event, the coastal region of Peru continued to have strong nearshore upwelling with primary production values greater than 2.5 grams of carbon per square meter per day, although the zone of high production was confined to a 250-kilometer-wide band, one-half its normal width. The biological effects of the 1975 event were short-lived; in April and May 1975 the equatorial region had begun to reestablish its normal levels of primary production.     

Wood versus fossil fuel as a source of excess carbon dioxide in the atmosphere: a preliminary report

If the amounts of wood consumed in deforestation to increase agricultural land and as firewood in underindustrialized countries are added to the amount consumed by the money economies as forest products, the estimates of the net amount of wood removed from the biosphere in this century should be revised upward. The per capita ratio of the weight of carbon from net wood burned to the weight of carbon from fossil fuel burned in this century has been at least 0.1 and may have approached 1.0.     

Analysis of gas in biological fluids by gas chromatography

Combining a vacuum extraction method with gas chromatography makes possible accurate, reproducible determination of small quantities of permanent gases contained in biological fluids. One useful application is demonstrated by determining the oxygen tension in 1 ml of human plasma.     

Externally suppressible proline quadruplet ccc U

Three (+1) frameshift mutations located at different genetic sites respond with high specificity to the same external suppressor. In each case, the suppressor restores small amounts of protein that is normal in electrophoretic mobility and heat stability. One of these proteins has been shown to have the wildtype amino acid sequence. The messenger RNA quadruplet CCCUappears to be common to all three frameshift sites and to be translated by the suppressor as proline. A likely suppressor agent is a proline transfer RNA with a quadruplet anticodon or its functional equivalent.     

M?ssbauer spectroscopy: recent developments

In this review I have emphasized two basic points. First, M?ssbauer spectroscopy has been widely used as a tool for basic research in solid-state physics, chemical structure, and magnetism. Second, the technique has been applied to many analytical and materials science problems where the nature of the sample prevents the use of more traditional approaches. M?ssbauer spectroscopy research on frozen solutions, colloids, interface chemistry, and crystallographic transformations can be expected to increase rapidly in the next few years.     

Compulsive sexual activity induced by p-chlorophenylalanine in normal and pinealectomized male rats

p-Chlorophenylalanine depletes brain serotonin and induces longlasting sexual excitation in male rats. The effect of p-chlorophenylalanine is potentiated by pargyline. Administration of 5-hydroxytryptophan to rats treated with p-chlorophenylalanine plus pargyline blocks the sexual excitation. p-Chlorophenylalanine also elicits sexual excitation in pinealectomized rats; this effect is not mediated by the lack of indole hormones in the pineal but may be the consequence of depletion of 5-hydroxytryptophan in the brain and the resulting imbalance between 5-hydroxytryptophan and catecholamine activity in the central nervous system.