IS EXTRATERRESTRIAL ORGANIC MATTER RELEVANT TO THE ORIGIN OF LIFE ON EARTH?

I review the relative importance of internal and external sources of prebiotic molecules on Earth at the time of life's origin 3.7Gyr ago. The efficiency ofsynthesis in the Earth's atmosphere was critically dependent on its oxidation state. If the early atmosphere was non-reducing and CO2-dominated, external delivery might havebeen the dominant source. Interplanetary dust grains and micrometeorites currently deliver carbonaceous matter to the Earth's surface at a rate of 3 × 10⁵kg/yr(equivalent to a biomass in 2Gyr), but this may havebeen as high as 5 × 10⁷kg/yr (a biomass in only10Myr) during the epoch of late bombardment. Much ofthe incoming material is in the form of chemically inactive kerogens and amorphous carbon; but if the Earth once had a dense (10-bar) atmosphere, small comets rich in avariety of prebiotic molecules may have been sufficiently air-braked to land non-destructively. Lingering uncertainties regarding the impact history of the Earth and the density and composition of its early atmosphere limit our ability to draw firm conclusions.     

IS IT NEUROSIS?

So-called “minor psychiatry,” the treatment of neurosis in persons who are not psychotic, may well be undertaken by the general practitioner.The first duty of the physician in dealing with a neurotic person is to determine whether psychosis may develop. He must be patient and thorough in hearing the history of the case and should have full information on the patient''s life and family.A recent classification of the neuroses is given and the more generally recognized symptoms of these conditions are described.     

IS LIFE IMPOSSIBLE? INFORMATION,SEX, AND THE ORIGIN OF COMPLEX ORGANISMS

The earliest organisms are thought to have had high mutation rates. It has been asserted that these high mutation rates would have severely limited the information content of early genomes. This has led to a well‐known “paradox” because, in contemporary organisms, the mechanisms that suppress mutations are quite complex and a substantial amount of information is required to construct these mechanisms. The paradox arises because it is not clear how efficient error‐suppressing mechanisms could have evolved, and thus allowed the evolution of complex organisms, at a time when mutation rates were too high to permit the maintenance of very substantial amounts of information within genomes. Here, we use concepts from the formal theory of information to calculate the amount of genomic information that can be maintained. We identify conditions under which much higher levels of genomic information can be maintained than previously considered possible among origin‐of‐life researchers. In particular, we find that the highest levels of information are maintained when many genotypes produce identical phenotypes, and when reproduction occasionally involves recombination between multiple parental genomes. There is a good reason to believe that these conditions are relevant for very early organisms, and thus the results presented may provide a solution to a long‐standing logical problem associated with the early evolution of life.     

DISABILITY—IS IT PERMANENT?

Too often cases of industrial injuries are submitted for permanent disability rating before maximum recovery is attained and the condition is permanent and stationary.This is frequently a situation that is detrimental to the injured working man, since his physical disability might be further reduced by additional treatment, and his future earning power and economic status thus be improved. Also it may be detrimental to the insurance carrier and/or employer, since in some instances it results in increased permanent disability award payments for portions of the condition which are not truly permanent.Inadequate medical reports also are a frequent cause of unfair awards. The necessary factors used to arrive at proper conclusions, the errors that have been observed and the importance of this problem are discussed.     

TROPAEOLUM UMBELLATUM: IS IT EXTINCT IN THE WILD?

The brief history of Tropaeolum umbellatum Hooker in cultivation is described, and the original illustration ( Fig. 1 ) is republished. Only three collections of this very distinct species appear to have been made in the wild, all in Ecuador around 1846, and no further records are noted either in the literature, or on the internet.

Figure 1 Open in figure viewer PowerPoint Tropaeolum tuberosum. From a hand‐coloured lithograph by W. H. Fitch in Curtis's Botanical Magazine 74, t. 4337(1848).