Cosmic rays,clouds, and climate

It has been proposed that Earth's climate could be affected by changes in cloudiness caused by variations in the intensity of galactic cosmic rays in the atmosphere. This proposal stems from an observed correlation between cosmic ray intensity and Earth's average cloud cover over the course of one solar cycle. Some scientists question the reliability of the observations, whereas others, who accept them as reliable, suggest that the correlation may be caused by other physical phenomena with decadal periods or by a response to volcanic activity or El Ni?o. Nevertheless, the observation has raised the intriguing possibility that a cosmic ray-cloud interaction may help explain how a relatively small change in solar output can produce much larger changes in Earth's climate. Physical mechanisms have been proposed to explain how cosmic rays could affect clouds, but they need to be investigated further if the observation is to become more than just another correlation among geophysical variables.     

Niningerite: a new meteoritic sulfide

Niningerite, a new meteoritic sulfide ranging in composition from (Fe(0.19)Mg(0.66)Mn(0.14)Ca(0.007)Cr(0.002))S to (Fe(0.52)Mg(0.33)Mn(0.06)Ca(0.06)Cr(0.03)Zn(0.004))S, from the type-I enstatite chondrites Abee, Saint Sauveur, Adhi-Kot, Indarch, St. Mark's, and Kota-Kota, is described. It is named in honor of H. H. Nininger.     

Cultural activity associated with prehistoric mammoth butchering and processing

Stacked mammoth bones at the Colby site in northern Wyoming reflect human cultural activity that is believed to have been peripheral to the butchering and processing of the animals. A projectile point found beneath the first bones placed in the pile leaves no doubt of human involvement in the stacking of the bones, but the significance of this kind of cultural activity is open to several interpretations.     

Oxidative N-dealkylation: a mannich intermediate in the formation of a new metabolite of lidocaine in man

Evidence is presented for a new metabolite of lidocaine. Its structure, N(1)-ethyl-2-methyl-N(3)-(2,6-dimethylphenyl)-4-imidazolidinone, suggests reactive electrophilic intermediates for the oxidative removal of N-alkyl groups in general.     

LONG-TERM ISOLATION STRESS IN RATS

Rats isolated for long periods became nervous and aggressive and developed caudal dermatitis ( scaly tail). After 13 weeks of isolation, rats had heavier adrenals and thyroid and lighter spleen and thymus compared with rats kept in community cages. This indicates an endocrinopathy with hyperfunction of the adrenal cortex.     

Accelerated healing of incisional wounds in rats induced by transforming growth factor-beta

The role of polypeptide growth factors in the processes of inflammation and repair was investigated by analyzing the influence of transforming growth factor-beta (TGF-beta), applied directly to linear incisions made through rat dorsal skin. A dose-dependent, direct stimulatory effect of a single application of TGF-beta on the breaking strength of healing incisional wounds was demonstrated. An increase in maximum wound strength of 220 percent of control was observed at 5 days; the healing rate was accelerated by approximately 3 days for at least 14 days after production of the wound and application of TGF-beta. These increases in wound strength were accompanied by an increased influx of mononuclear cells and fibroblasts and by marked increases in collagen deposition at the site of application of TGF-beta. TGF-beta is thus a potent pharmacologic agent that can accelerate wound healing in rats.