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If some countries lead by example, standards may increasingly become normalized.

Children with language-based learning impairments (LLIs) have major deficits in their recognition of some rapidly successive phonetic elements and nonspeech sound stimuli. In the current study, LLI children were engaged in adaptive training exercises mounted as computer "games" designed to drive improvements in their "temporal processing" skills. With 8 to 16 hours of training during a 20-day period, LLI children improved markedly in their abilities to recognize brief and fast sequences of nonspeech and speech stimuli.

A speech processing algorithm was developed to create more salient versions of the rapidly changing elements in the acoustic waveform of speech that have been shown to be deficiently processed by language-learning impaired (LLI) children. LLI children received extensive daily training, over a 4-week period, with listening exercises in which all speech was translated into this synthetic form. They also received daily training with computer "games" designed to adaptively drive improvements in temporal processing thresholds. Significant improvements in speech discrimination and language comprehension abilities were demonstrated in two independent groups of LLI children.

Under prebiotic conditions, formaldehyde adds to uracil at the C-5 position to produce 5-hydroxymethyluracil with favorable rates and equilibria. Hydroxymethyluracil adds a variety of nucleophiles, such as ammonia, glycine, guanidine, hydrogen sulfide, hydrogen cyanide, imidazole, indole, and phenol, to give 5-substituted uracils with the side chains of most of the 20 amino acids in proteins. These reactions are sufficiently robust that, if uracil had been present on the primitive Earth, then these substituted uracils would also have been present. The ribozymes of the RNA world would have included many of the functional groups found in proteins today, and their catalytic activities may have been considerably greater than presently assumed.

A combined gas chromatographic-mass spectrometric technique was used to identify and quantitate the occurrence of myo-, chiro-, and scyllo-inositol in marine sediments. The most abundant isomer was myo-inositol. These inositols were found in all the organic-rich sediment samples examined, and the amount of inositol decreased steadily with the age of the sample. A small fraction of the inositols occurred as hexaphosphate esters.

Nicotinonitrile, 2-cyanopyridine, and 4-cyanopyridine can be synthesized under primitive earth conditions by the action of electric discharges on ethylene and ammonia. The electric discharge first synthesizes pyridine and hydrogen cyanide, which react in the discharge to form the cyanopyridines. Nicotinonitrile would have hydrolyzed in the primitive ocean to nicotinamide and nicotinic acid.

Methionine has been shown to be a product of the action of a spark discharge on a simulated primitive earth atmosphere containing CH(4), N(2), NH(3), H(2)O, and H(2)S or CH(3)SH. Acrolein has also been shown to be a product of the discharge and is proposed as an intermediate in the prebiotic synthesis of methionine and of glutamic acid, homocysteine, homoserine, and alpha,gamma-diaminobutyric acid.

Measurements of the dissociation pressure of carbon dioxide hydrate show that this hydrate (CO(2) . 6H(2)O) is stable relative to solid CO(2) and water ice at temperatures above about 121 degrees K. Since this hydrate forms from finely divided ice and gaseous CO(2) in several hours at 150 degrees K, it is likely to be present in the martian ice cap. The ice cap can consist of water ice, water ice + CO(2) hydrate, or CO(2) hydrate + solid CO(2), but not water ice + solid CO(2).

Measurements of the dissociation pressure of nitrogen hydrate and oxygen hydrate show that the clathrate hydrate of air with the formula (N(2), O(2)) 6H(2)O should exist below about 800 meters in the Antarctic ice sheet. This accounts for the disappearance of gas bubbles at depths greater than 1200 meters. The hydrate should exist from this depth to prise 0.06 percent of the ice.

Phenylacetylene can be synthesized in substantial yields from various hydrocarbons by high temperatures, electric discharges, and ultraviolet light. Phenylacetylene is hydrated to phenylacetaldehyde by way of both nucleophilic and radical additions of H(2)S followed by hydrolysis of the thtioaldehyde. The addition of NH(3) and HCN to phenylacetaldehyde yields phenylalanine nitrile which is hydrolyzed to phenylalanine. A small yield of tyrosine is obtained from the radical addition of H(2)S to phenylacetylene. This sequence of reactions is a possible mechanism for the synthesis of these amino acids on the primitive earth.

If ion exchange on clay minerals regulated the cationts in the primitive ocean as it does in the present ocean, the pH would have been 8 and the K(+) concentration 0.01M. Since NH(4)(+) and K(+) are similar in their claymineral equilibria, the maximum NH(4) (+) concentration in the primitive ocean would also have been 0.01M. An estimate of the minimum NH(4)(+) concentratin is 1 x 10(-3)M, based on the reversible deamination of aspartic acid and the assumption that aspartic acid is necessary for the origin of life. The rate of this nonenzymic deamnination is rapid on the geological time scale.